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You are an expert at summarizing long articles. Proceed to summarize the following text: This application is a continuation of, and claims the benefit of, U.S. patent application Ser. No. 09/821,299 filed on Mar. 29, 2001, now U.S. Pat. No. 6,481,178 which is a continuation-in-part of U.S. patent application Ser. No. 09/654,024 filed on Sep. 1, 2000, now U.S. Pat. No. 6,363,683 and which is a continuation of U.S. Ser. No. 09/008,437, now U.S. Pat. No. 6,170,220, filed Jan. 16, 1998, and issued Jan. 9, 2001, all of which are incorporated herein in their entireties. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention encompasses a building component used to make concrete structures. 2. Background Art Concrete walls in building construction are most often produced by first setting up two parallel form walls and pouring concrete into the space between the forms. After the concrete hardens, the builder then removes the forms, leaving the cured concrete wall. This prior art technique has drawbacks. Formation of the concrete walls is inefficient because of the time required to erect the forms, wait until the concrete cures, and take down the forms. This prior art technique, therefore, is an expensive, labor-intensive process. Accordingly, techniques have developed for forming modular concrete walls that use a foam insulating material. The modular form walls are set up parallel to each other and connecting components hold the two form walls in place relative to each other while concrete is poured therebetween. The form walls, however, remain in place after the concrete cures. That is, the form walls, which are constructed of foam insulating material, are a permanent part of the building after the concrete cures. The concrete walls made using this technique can be stacked on top of each other many stories high to form all of a building's walls. In addition to the efficiency gained by retaining the form walls as part of the permanent structure, the materials of the form walls often provide adequate insulation for the building. One embodiment of form walls is disclosed in U.S. Pat. No. 5,390,459, which issued to Mensen on Feb. 21, 1995, and which is incorporated herein by reference. This patent discloses “bridging members” that comprise end plates connected by a plurality of web members. The bridging members also use reinforcing ribs, reinforcing webs, reinforcing members extending from the upper edge of the web member to the top side of the end plates, and reinforcing members extending from the lower edge of the web member to the bottom side of the end plates. As one skilled in the art will appreciate, this support system is expensive to construct, which increases the cost of the formed wall. Also, these walls cannot feasibly be used to make floors or roof panels. SUMMARY OF THE INVENTION The present invention provides an insulated concrete form comprising at least one longitudinally-extending side panel and at least one web member partially disposed within the side panel. The web member extends from adjacent the external surface of the side panel through and out of the interior surface of the side panel. Three embodiments of the present invention that may be used to construct a concrete form are described herein. The first embodiment uses opposed side panels that form a cavity therebetween into which concrete is poured and substantially cured. The second embodiment uses a single side panel as a form, onto which concrete is either poured or below which concrete is poured and the form inserted into. Once the concrete cures and bonds to the side panel in the second embodiment, it is used as a tilt-up wall, floor, or roof panel. The third embodiment operates similar to the first embodiment but, instead of having two opposed side panels to form the cavity, the present invention uses one side panel and an opposed sheet or other form on the opposed side to form the cavity. After the concrete substantially cures in the third embodiment, the sheet can be removed and reused again or, alternatively, remain as part of the formed structure. If the sheet is removed, the resulting structure is similar to a tilt-up wall formed using the second embodiment of the present invention. In the first embodiment, the web member is preferably partially disposed in the side panel so that a portion of the web member projects beyond the interior surface of the side panel and faces but does not touch an opposing side panel. The first embodiment also uses a connector that attaches to the two web members in opposing side panels, thereby bridging the gap between the two side panels to position the side panels relative to each other. The connectors preferably have apertures to hold horizontally disposed re-bar. The connectors also have different lengths, creating cavities of different widths for forming concrete walls having different thicknesses. The connectors are interchangeable so that the desired width of the wall can be set at the construction site. For the second embodiment, a portion of the web member preferably projects beyond the interior surface of the side panel. In one design, the side panel is first horizontally disposed so that the interior surface and portion of the web member extending therethrough are positioned upwardly. Forms are placed around the periphery of the side panel and concrete is then poured onto the interior surface. In a second design, the concrete is poured into a volume defined by perimeter forms and then the side panel is placed upon the fluid concrete so that at least a portion of the web member in the side panel is disposed in the concrete. Alternatively, a third design is formed as a hybrid of the first and second designs, namely, one side panel is horizontally disposed, concrete is poured onto the interior surface and contained by forms, and then another panel is place upon the poured concrete so that side panels are on both sides of the concrete. For all three designs, once the concrete substantially cures and bonds with the interior surface of the side panel and the portion of the web member extending therethrough, the side panels and connected concrete slab can be used as a tilt-up wall, flooring member, or roof panel. The third embodiment of the present invention encompasses a process generally similar to the first embodiment, except that a sheet of plywood or the like is used instead of a second side panel. The sheet can either be removed after the concrete cures and used again or remain part of the formed structure. The present invention further comprises components to improve the walls formed using side panels and to simplify the construction process. BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWINGS FIG. 1 is a perspective view of a first embodiment of the present invention. FIG. 2 is a perspective side view of a FIG. 1 taken along line 2 — 2 . FIG. 2A is an alternative view of FIG. 2 showing concrete disposed between the two opposed side panels. FIG. 2A also shows the tilt-up wall formed with side panels on the two opposed sides of the concrete that has been erected. FIG. 3 is a perspective view of one side panel shown in FIG. 1, in which three web members show four attachment points extending through the interior surface of the side panel. Two of the web members show two connectors attached to attachment points and one web member shows two connectors and a stand-alone web member attached to those two connectors. FIG. 4 is a perspective view of the connector shown in FIG. 3 . FIG. 4A is a perspective view of an alternative of the connector shown in FIG. 4 . FIG. 5 is a perspective view of one design of the side panel of the present invention, in which a portion of the side panel is cut away to show the body portion of the web member partially disposed and integrally formed therein. FIG. 6 is an exploded perspective view of an alternative design of the web member shown in FIGS. 3 and 5 and having five attachment points instead of four. FIG. 6 also shows an anchor and an extender used in conjunction with the different embodiments of the present invention. FIG. 7 is a perspective view of a second embodiment of the present invention showing generally the concrete formed below the side panel. FIG. 8 is another perspective view of the second embodiment of the present invention showing generally the concrete formed above the side panel. FIG. 9 is a perspective view of a third embodiment of the present invention showing a cavity defined by a side panel and a sheet. FIG. 9A is an alternative view of FIG. 9 showing concrete disposed between the side panel and the sheet. FIG. 10 is a perspective view of a stand-alone web member and a connector, both of which include a spacer. FIG. 11 is a perspective view of an upstanding concrete structure formed by two of the second embodiments or the third embodiment of the present invention, which are shown in FIGS. 7, 8 , 9 , and 9 A. FIG. 12 is a cross-sectional side view showing two opposed side panels and the web members partially disposed therein, in which the side panels are interconnected in various combinations by flexible linking members joining extenders or slots formed into the web members. FIG. 13 is a top plan view of a T-wall formed, in part, using flexible linking members. FIG. 14 is an expanded perspective view of a web member removable insertable into a side panel. DETAILED DESCRIPTION OF THE INVENTION The present invention is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. As used in the specification and in the claims, “a,” “an,” and “the” can mean one or more, depending upon the context in which it is used. The preferred embodiment is now described with reference to the figures, in which like numbers indicate like parts throughout the figures. As shown in FIGS. 1-12, the present invention comprises a concrete form system 10 used for constructing buildings. A first embodiment of the present invention, shown best in FIGS. 1-2A, comprises at least two opposed longitudinally-extending side panels 20 , at least one web member 40 partially disposed within each of the side panels 20 , and a connector 50 disposed between the side panels 20 for connecting the web members 40 to each other. As shown in FIG. 2A, concrete C is poured between the side panels 20 so that it bonds with the side panels 20 and the web members 40 . Two designs of a second embodiment of the present invention, which is discussed in more detail below and shown in FIGS. 7 and 8, involves using a single side panel 20 that bonds with the concrete C, instead of using opposed side panels 20 on both sides of the concrete C. The second embodiment also includes a design in which the wall has side panels 20 on both sides of the concrete to appear as the wall in FIG. 2A, but is formed differently from the first embodiment. A third embodiment of the present invention is shown in FIGS. 9 and 9A and is similar to the first embodiment, but uses one side panel 20 and a sheet 80 instead of two opposed side panels 20 . Each side panel 20 has a top end 24 , a bottom end 26 , a first end 28 , a second end 30 , an exterior surface 32 , and an interior surface 34 . The presently preferred side panel 20 has a thickness (separation between the interior surface 34 and exterior surface 32 ) of approximately two and a half (2½) inches, a height (separation between the bottom end 26 and the top end 24 ) of sixteen (16) inches, and a length (separation between the first end 28 and second end 30 ) of forty-eight (48) inches. The dimensions may be altered, if desired, for different building projects, such as increasing the thickness of the side panel 20 for more insulation. Half sections of the side panels 20 can be used for footings. Referring now to FIGS. 1 and 2 showing the first embodiment of the present invention, the interior surface 34 of one side panel 20 faces the interior surface 34 of another side panel 20 and the opposed interior surfaces 34 are laterally spaced apart from each other a desired separation distance so that a cavity 38 is formed therebetween. Concrete—in its fluid state—is poured into the cavity 38 and allowed to substantially cure (i.e., harden) therein to form the wall 10 , as shown in FIG. 2 A. Preferably, for the first embodiment, the opposed interior surfaces 34 are parallel to each other. The volume of concrete received within the cavity 38 is defined by the separation distance between the interior surfaces 34 , the height of the side panels 20 , and the length of the side panels 20 . The side panels 20 are preferably constructed of polystyrene, specifically expanded polystyrene (“EPS”), which provides thermal insulation and sufficient strength to hold the poured concrete C until it substantially cures. The formed concrete wall 10 using polystyrene with the poured concrete C has a high insulating value so that no additional insulation is usually required. In addition, the formed walls have a high impedance to sound transmission. As best shown in FIGS. 3 and 5, the interior surface 34 preferably includes a series of indentations 36 therein that increase the surface area between the side panels 20 and concrete C to enhance the bond therebetween. To improve further the bond between the side panels 20 and the concrete C poured in the cavity 38 , a portion of each of the web members 40 formed in or passing through the side panels 20 extends through the interior surface 34 of the side panels 20 into the cavity 38 . A portion of each web member 40 is preferably integrally formed within one side panel 20 and is also cured within the concrete C so that the web member 40 strengthens the connection between the side panel 20 and the concrete C. That is, since the web member 40 is preferably an integral part of the side panel 20 , it bonds the side panel 20 to the concrete C once the concrete is poured and substantially cures within the cavity 38 . However, other designs are contemplated, such as designs in which the web member is not integrally formed into the side panel and, for example, the web member is slid into slots precut into the side panel at the construction site, which is shown in FIG. 14 . As shown in FIGS. 1-3 and 5 , each side panel 20 has at least one web member 40 formed into it. Preferably, the each web member 40 formed within one side panel 20 is separated a predetermined longitudinal distance from other web members 40 , which is typically eight (8) inches. Based on the preferred length of the side panel 20 of forty-eight (48) inches, six web members 40 are formed within each side panel 20 , as shown in FIGS. 3 and 5. Portions of each web member 40 that extend through the interior surface 34 of the side panel 20 forms one or more attachment points 44 . The attachment points 44 are disposed within the cavity 38 and are preferably spaced apart from the interior surface 34 of the side panels 20 in the first embodiment. However, as one skilled in the art will appreciate, the attachment points 44 may take any of a number of alternate designs formed by or independently of the web members 40 , including as examples: slots, channels, grooves, projections or recesses formed in the side panels; hooks or eyelets projecting from or formed into the side panels; twist, compression or snap couplings; or other coupling means for engaging cooperating ends of the connectors. Preferably, as addressed in more detail below and as shown best in FIGS. 3, 5 , and 6 , each attachment point 44 is substantially rectangular and flat in plan view to be complementarily and slidably received within one respective end 52 of the connector 50 . Thus, in the first embodiment, the connectors 50 shown in FIGS. 4 and 4A engage two attachment points 44 on opposed web members 40 , which position the interior surfaces 34 of the side panels 20 at a desired separation distance and support the side panels 20 when the fluid concrete is poured into the cavity 38 . In the preferred embodiment, the connector 50 makes a two-point connection with opposed web members 40 because each connector has two ends 52 that each couple to one attachment point 44 , although it is contemplated making a four-point connection (i.e., each connector 50 engages four attachment points 44 instead of two as illustrated in the figures). Referring now to FIGS. 3, 6 , and 10 , each web member 40 also preferably has an end plate 42 that is disposed adjacent the exterior surface 32 of the side panel 20 in the preferred embodiment. The end plates 42 are preferably substantially rectangular in plan view. Except when used as a stand-alone web member 40 ′ for the third embodiment as discussed below, each end plate 42 of the web members 40 is preferably completely disposed within a portion of one respective side panel 20 , as shown best in FIGS. 2 and 5. That is, the end plates 42 are located slightly below the exterior surface 32 of, or recessed within, the side panel 20 , preferably at a distance of one-quarter (¼) of an inch from the exterior surface 32 . This position allows for easily smoothing the surface of the side panels 20 without cutting the end plate 42 should the concrete, when poured, create a slight bulge in the exterior surface 32 of the side panels 20 . However, when embedded within the side panel 20 , it is desired that some visual indicia be included on the external surface 32 to enable the construction worker to locate quickly and accurately the end plate 42 . Alternatively, the end plates 42 can abut the exterior surface 32 of panels 20 so that a portion of the end plate 42 is exposed over the exterior surface 32 . It is also preferred in the first and third embodiments that each end plate 42 is oriented substantially upright and disposed substantially parallel to the exterior surface 32 of the side panel 20 when forming a concrete form 10 . Similar to the end plate 42 , the attachment points 44 are also preferably oriented substantially upright in the first and third embodiments so that one attachment point 44 is disposed above another attachment point 44 . As best shown in FIGS. 2, 3 , and 9 , in one design each of the web members 40 has four spaced-apart attachment points 44 , in which the attachment points 44 for each web member 40 are vertically disposed within the cavity 38 in a substantially linear relationship. The attachment points 44 are placed in two groups-a top group of two attachment points 44 and a bottom group of two attachment points 44 . Adjacent attachment points 44 in the two groups are spaced apart a first distance from each other, preferably approximately two and an eighth (2⅛) inches apart between center points. In addition, the closest attachment points 44 of the two groups, i.e., the lowermost attachment point 44 of the top group and the uppermost attachment point 44 of the bottom group, are spaced apart a second distance from each other. The second distance, which is approximately six (6) inches in the preferred embodiment for a twelve (12) inch connector, is more than double and almost triple the first distance. In an alternative design, the web member 40 includes five attachment points 44 , which is illustrated best in FIG. 6 . This design also has the two groups of two attachment points 44 as discussed above, but also includes a fifth attachment point 44 at approximately the center of the two groups. This design having five attachment points 44 is presently preferred over the web member 40 having four attachment points because it provides even greater flexibility for the architect and/or construction worker. As one skilled in the art will appreciate, the number of attachment points 44 used for each web member 40 can be further varied in number and spacing based on relevant factors such as the dimensions of the side panels 20 and the wall strength or reinforcement desired. The designs of the multiple attachment points 44 of the present invention is an improvement over prior art systems, which lack multiple mounting points for attaching an interconnecting device. The side panels 20 and web members 40 in the present invention can be cut horizontally over a wide range of heights to satisfy architectural requirements, such as leaving an area for windows, forming odd wall heights, and the like, yet still have at least two or three attachment points 44 to maintain structural integrity of the wall. Prior art systems, in contrast, lose structural integrity if cut horizontally, thus requiring extensive bracing to resist collapsing when concrete is poured into the cavity between the panels. One skilled in the art, however, will appreciate that the web member of the present invention is not limited to these exemplary designs and can include other shapes in which a portion is disposed adjacent both the interior and exterior surfaces in which the web member is disposed. Referring again to FIGS. 1 and 2 showing the first embodiment of the present invention, the attachment points 44 of the web members 40 extend into the cavity 38 and the attachment points 44 of each web member 40 formed within one side panel 20 are spaced apart from the attachment points 44 of the web members 40 formed within the opposed side panel 20 . Thus, the web members 40 preferably do not directly contact each other; instead, each attachment point 44 independently engages the connector 50 that interconnects the web members 40 and, accordingly, the side panels 20 . Referring now to FIGS. 4 and 4A, the illustrated connectors 50 have opposed ends 52 and a length extending therebetween. The ends 52 of the connectors 50 are each of a shape to engage one attachment point 44 of two respective web members 40 within opposed panels. As mentioned above and as best shown in FIGS. 5, 6 , and 12 , the attachment points 44 are preferably substantially rectangular and flat and a stem 48 extends the attachment point 44 through the side panel 20 from the remaining portions of the web member 40 . As such, the stem 48 and the attachment point 44 are “T” shaped in cross-sectional view, in which the attachment point forms the top of the “T.” In conjunction, as best shown in FIGS. 4 and 4A, each end 52 of the connector 50 has a track 54 into which the preferably rectangular attachment point 44 is complementarily and slidably received. The connector 50 , accordingly, is movable between a separated position and an attached position. In the separated position (as illustrated, for example, in FIGS. 4 and 4 A), the end 52 of the connector 50 is spaced apart from the respective attachment point 44 to which it will be connected. In the attached position, the end 52 of the connector 50 is engaged to the attachment point 44 , which is shown, for example, in FIGS. 2 and 3. In the preferred embodiment, the ends 52 of the connector 50 are detachably locked to the respective attachment points 44 when in the attached position. By being detachably locked, it will be appreciated that, while only contacting the connector 50 , an applying force needed to remove the connector 50 from the attachment point 44 is greater than a force needed to attach that connector to that attachment point 44 . Stated differently, an applying force needed to move the connector 50 from the separated to the attached position is less than a removing force needed to move the connector 50 from the attached to the separated position. The differences in the applying and removing forces may be slight or significant and still be within the scope of the present invention. The present invention thus comprises a means for detachably locking the end 52 of the connector 50 into the attached position. The preferred embodiment of the locking means is illustrated in FIGS. 4A and 6. Referring first to FIG. 6, latching members 46 are disposed either above and below the attachment points 44 , although it is acceptable if only one latching member 46 is disposed either above or below the attachment point 44 . The latching members 46 are preferably integrally formed as part of the web member 40 , but can alternatively either be affixed to the web member 40 after it is formed or be connected to the side panel 20 . As shown in FIG. 6, the tip 47 of the latching member 46 is spaced apart from the attachment point 44 and, preferably, flexibly movable but predisposed or biased to be in an extended position, again as shown in FIG. 6 . Since it is preferred that the tip 47 of the latching member 46 be flexible, the latching member 46 may be formed as a relatively thin component, which should not prevent the latching member 46 from performing its intended function. In conjunction, referring again to FIG. 4A, the connector 50 has a detent 58 disposed above its track 54 . Specifically, the illustrated detent 58 is an indentation formed at the center of the closed end of the track 54 (which is shown as the top end in FIG. 4 A). It is further preferred that the detent 58 include a raised back 59 that is located at the back end of the detent 58 . As one skilled in the art will appreciate, however, the detent 58 can be aligned differently such that, for example, the detent 58 is in the center of the closed end of the track 54 instead of at its top or the detent 58 is off-center instead of in the middle of the closed end. To move the connector 50 shown in FIG. 4A to the attached position onto the web member 40 shown in FIG. 6, the bottom of the track 54 of the connector 50 is aligned with the top edge of a one attachment point 44 and slid vertically downwardly while the web member 40 is oriented in an upstanding position. Although not preferred or discussed further, the connector could alternatively be aligned with the bottom edge of the selected attachment point and slid upwardly. As the closed portion of track 54 of the connector 50 slides closer to the attachment point 44 while moving downwardly, the closed portion contacts the flexible tip 47 of the latching member 46 . That contact moves the tip 47 of the latching member 46 inwardly toward the end plate 42 of the web member 40 until the detent 58 is aligned with the tip 47 of the latching member 46 , at which time the latching member 46 extends outwardly away from the end plate 42 to its normal extended position to be complementarily received within the detent 58 . Thus, at that point (which preferably is reached when the attachment point 44 is fully received within the track 54 of the connector 50 ), the connector 50 is detachably locked into place by the tip 47 of the latching member 46 being positioned within the detent 58 so that the connector 50 cannot be freely removed from the attachment point 44 . In conjunction, the raised back 59 behind the detent 58 prevents the tip 47 from over extending beyond the detent 58 . As one skilled in the art will appreciate, the locking means shown in FIGS. 4A and 6 allows the connector 50 to be easily slid down onto the attachment point 44 using very light downward force (i.e., with just two fingers) to latch the connector 50 to the attachment point 44 . That is, the preferred embodiment of the connector 50 shown in FIGS. 4A and 6 allows a construction worker to slide relatively “loosely” the end 52 of the connector 50 onto the attachment point 44 without significant frictional resistance. Such a design is advantageous because even mild frictional resistance may be burdensome given the number of connectors 50 involved in some construction projects, which may literally involve thousands of connectors 50 each attaching to two web members 40 in opposed side panels 20 . The scope of the connections made may be appreciated by considering FIG. 2, which shows the connections for one pair of opposed side panels 20 . As such, this less burdensome process may translate into a reduction in the amount of time necessary to attach the connectors 50 to the attachment points 44 . To remove the connector 50 from the attachment point 44 back to the separated position (which is unusual to occur during a construction project), the flexible tip 47 of the latching member 46 must be pressed inwardly away from the detent 58 and toward the end plate 42 and, concurrently, the connector 50 must be slid upwardly toward the latching member 46 a sufficient distance so that the tip 47 of the latching member 46 is no longer aligned or in registry with the detent 58 . After this initial movement, the connector 50 can be removed from the attachment point 44 , either while still holding the tip 47 of the latching member 46 in the compressed position or releasing the latching member 46 so that its tip 47 contacts the closed portion of the track 54 . Thus, although there is low frictional resistance moving the connector 50 to the attached position, the detachably locked connector 50 cannot easily be removed—even with strong upward force—unless the flexible tip 47 of the latching member 46 is compressed, which often requires a two-handed operation to separate the connector 50 from the web member 40 . This latching design further allows a construction worker or foreman to verify that a connector 50 is properly attached to the web members 40 by tapping on the bottom of the connector 50 and having the connector 50 remain in place, whereas other designs might result in the connector 50 “popping off” the attachment points 44 in response to such an upward tapping force. Further, the detachably locking design also more effectively resists the upward forces exerted by concrete to the connectors 50 as the fluid concrete is first placed, or pumped, into the cavity 38 of the concrete form. In so resisting the forces applied by the fluid concrete, the connectors 50 keep the side panels 20 in place and maintain the integrity of the structure when subjected to various forces or pressures. Another embodiment of the locking means is shown referring to FIG. 4 . As will be noted, the track 54 of the connector 50 forms a gap 56 into which a portion of the stem 48 is complementarily received when the connector 50 is moved to the attached position. The locking means in this embodiment comprises at least one barb 55 on the track 54 of the connector 50 that is oriented into the gap 56 and a corresponding indentation 49 on the stem 48 of the web member 40 (as shown in FIG. 6 ). As such, when the connector 50 is in the attached position, the barb 55 is complementarily received into the indentation 49 . FIG. 4 shows two spaced-apart barbs 55 extending toward each other in the gap and there would be two corresponding indentations 49 formed into the stem 48 . These barbs 55 provide a frictional fit between the connector 50 and the attachment point 44 of the web member 40 to hold the connector 50 at the attached position. However, the frictional resistance also exists when moving the connectors 50 to the attached position, which makes this embodiment of the locking means less desired. One skilled in the art will appreciate that the locking means for the connectors 50 can also be used for the stanchions (some embodiments of which are discussed below and shown in FIG. 6 ). One skilled in the art will further appreciate that other locking means are possible, such as having the latching member 46 formed on the connector 50 and the detent 58 formed on the web member 40 . Referring again to FIGS. 2, 4 , and 4 A, the connectors 50 also preferably define an aperture 56 of a size to complementary receive a re-bar (not shown) therein. The rebar provides reinforcing strength to the formed wall. The diameter of the re-bar can be one quarter (¼) inch or other dimension as required for the necessary reinforcement, which depends on the thickness of the concrete wall and the design engineering requirements. The connectors 50 preferably have two or more apertures 56 and re-bar can be positioned in any of the apertures 56 before the concrete is poured into the cavity 38 . The apertures 56 can be designed so that the re-bar is securably snapped into place for ease of assembly. To vary the width of the cavity 38 (i.e., the separation between the interior surfaces 34 of the opposed side panels 20 ), different connectors 50 can have varying lengths. The width of the cavity 38 can be two (2), four (4), six (6), eight (8) inches or greater separation. Different connectors 50 are sized accordingly to obtain the desired width of the cavity 38 . Also, as one skilled in the art will appreciate, the fire rating, sound insulation, and thermal insulation increase as the width of the cavity 38 , which is filled with concrete, increases. One skilled in the art will appreciate that the cavity 38 may only be partially filled with concrete, but such an embodiment is not preferred or desired. The web members 40 and connectors 50 are preferably constructed of plastic, more preferably high-density plastic such as high-density polyethylene or high-density polypropylene, although other suitable polymers may be used. Other contemplated high-density plastics include acrylonitrile butadiene styrene (“ABS”) and glass-filled polyethylene or polypropylene, particularly for connectors and stanchions since they are more expensive materials. Factors used in choosing the material include the desired strength of the web member 40 and connector 50 and the compatibility with the material used to form side panels 20 and with the concrete. Another consideration is that the end plates 42 should be adapted to receive and frictionally hold a metal fastener, such as a nail or screw, therein, thus providing the “strapping” for a wall system that provides an attachment point for gypsum board (not shown), interior or exterior wall cladding (not shown), or other interior or exterior siding (not shown). Thus, the web members 40 function to align the side panels 20 , hold the side panels 20 in place during a concrete pour, and provide strapping to connect siding and the like to the formed concrete wall 10 . Referring again to FIG. 1, one skilled in the art will appreciate that a plurality of side panels 20 can be longitudinally aligned to form a predetermined length and be vertically stacked to form a predetermined height. For example, as shown in FIG. 1, the first end 28 of one side panel 20 abuts the second end 30 of another side panel 20 and the bottom end 26 of one side panel 20 is disposed on the top end 24 of another side panel 20 . Thus, a series of side panels 20 can be aligned and stacked to form the concrete system 10 into which concrete C is poured to complete the construction of the wall 10 . One consideration, however, is that the side panels 20 are not vertically stacked too high and filled at once so that the pressure on the bottom side panel 20 is greater than the yield strength of the web members 40 or EPS side panels 20 . Instead, the stacked wall of panels 20 can be filled and cured in stages so that the static and dynamic pressures are not excessive on the lower side panels 20 . To facilitate the stacking of the components, the side panels 20 are optionally provided with a series of projections 35 and indentations 37 that complementarily receive offset projections 35 and indentations 37 from another side panel 20 (i.e., a tongue-and-groove-type system). The projections 35 and indentations 37 in the adjacent side panels 20 mate with each other to form a tight seal that prevents leakage of concrete C during wall formation and prevents loss of energy through the formed wall. Referring still to FIG. 1 for the first embodiment of the present invention, the present invention also uses corner sections 39 . Preferably, each corner section 39 forms a substantially right angle and concrete C is also poured into the corner section similar to the other sections of the concrete form system 10 . Forty-five degree angle corner sections can also be used. Thus, the formed concrete wall is contiguous for maximum strength, as opposed to being separately connected blocks. Still another embodiment of the present invention, which is not shown, uses non-linear side panels so that the formed wall has curvature instead of being straight. The first embodiment of the present invention is an improvement over the prior art. Although other systems may use connector elements, the prior art lacks a web member 40 having an end plate 42 , which provides a nailing/screwing strip adjacent the exterior surface 32 of the side panel 20 , and has an attachment point 44 or similar connection projecting into the cavity 38 adjacent the interior surface 34 . Moreover, the present invention uses less plastic and is, therefore, less expensive to manufacture. Furthermore, in prior art systems, the panels are made so that large, thick, plastic connector elements slide down in a “T” slot formed within the inside surface of the panel itself. These prior art designs are structurally weaker and the construction workers in the field have substantial difficulty avoiding breaking the panels while sliding the connector element into place. Additionally, the prior art panels can break off from the cured concrete if any “pulling” occurs while mounting sheetrock or other materials onto the outer side of the panel. The preferred embodiment of the present invention having the web member 40 integrally formed into the side panel 20 provides a stronger “interlocking” system among the side panels 20 , the web member 40 , and the connectors 50 , which are imbedded within concrete in the cavity 38 . Nonetheless, as mentioned above, it is contemplated within the scope of the present invention using web members 40 that are not integrally formed into the side panels 20 . Now moving to the second embodiment of the present invention, as noted above, there are three methods of constructing the tilt-up walls 10 of the present invention: (1) pouring the concrete and then inserting the panel 20 into the poured concrete, which is also known as “wet-setting” and is shown in FIG. 7; (2) pouring the concrete onto a substantially horizontally-disposed side panel 20 , which is shown in FIG. 8; or (3) pouring the concrete onto a substantially horizontally-disposed side panel 20 and then inserting the panel 20 into the top surface of the poured concrete so that the concrete is “sandwiched” between two opposed side panels 20 and, when erected, appears the same as the wall 10 formed by the first embodiment shown in FIG. 2 A. All of the walls 10 formed by these three methods or designs are known as tilt-up walls. As noted, the first two designs of the second embodiment use a side panel 20 on only one side of the formed concrete structure 10 , unlike the third design that uses opposed side panels covering both faces of the concrete C. Thus, the walls 10 formed by the first two designs of this embodiment are insulated on one side, which may be either the interior or exterior of the wall. Leaving the external surface as a concrete surface without a side panel is advantageous for insect control, such as preventing termite infestation since termites cannot burrow through concrete C, but may attack and bore through EPS—the preferred material to form the side panels 20 . Alternatively, leaving the interior surface as a concrete surface is advantageous for warehouses in which fork lifts, for example, could potentially damage any interior finishes by forcefully contacting them, whereas a concrete surface subjected to the same contact will remain substantially unimpaired. The side panels 20 may extend the full or a partial height of the tilt-up wall and, as discussed above, provide both sound impedance and thermal insulation. For the wet-setting method shown in FIG. 7, it is preferred that a concrete floor slab (not shown), which will serve as a casting base for the tilt-up walls, is formed on a prepared, well-compacted subbase. It has been found that a five-inch (5″) or thicker slab is desired. Also, instead of forming the entire floor during the initial pouring, the slab is typically held back several feet from its ultimate perimeter dimension (i.e., the interior boundaries of the building) to allow space for raising and setting the tilt-up walls after being formed on the floor slab. As discussed below, the gap that exists is subsequently filled in after the tilt-up walls are later erected. After the floor slab cures, the perimeter foundations or forms (not shown) within which the concrete is poured for forming the tilt-up walls are next positioned and braced to form a substantially contained volume. The perimeter forms are often dimension lumber of sufficient width to allow the walls to be made the desired thickness. Once the periphery forms are in place, door and window openings are blocked out and set. One skilled in the art will also appreciate that reinforcement, typically re-bar, is also positioned within the perimeter forms to be contained within the interior of the tilt-up wall after the concrete is poured. Likewise, items to be embedded within the tilt-up wall, such as for attachments for the lifting cables (discussed below), are also positioned within the perimeter forms. Concurrently, the side panels 20 are sized and interconnected to match (or, if desired, be smaller than) the length and width dimensions of the tilt-up sections to be cast. Specifically, the side panels 20 are joined together using the projections 35 and indentations 37 (i.e., tongue-and-groove-type connectors) so that a top end 24 of one panel 20 abuts a bottom end 26 of another panel 20 and/or a first end 28 of one panel 20 abuts a second end 30 of another. The side panels 20 are usually joined in a side-by-side configuration while they are horizontally oriented. The assembled side panels 20 forming an array of panels are preferably fastened together using strongbacks (not shown), which are often a metal “C”-shaped channel or similar device that provides stiffness to the array. Screws are typically used to interconnect the end plates 42 of the web members 40 to the strongbacks, which run the entire height or length of the assembled array of panels 20 . Either before or after fastening the array of panels together, the side panels 20 are cut not only for height and width dimensions, but also for any penetrations to be included within the tilt-up wall (i.e., windows and doorways), embedded items, and welding plates. The assembled panels with strongbacks are then staged to be “wet set” after consolidation and screeding of the concrete. With the preliminary steps completed, a release agent is sprayed or poured onto the concrete floor slab or other surface used, if not completed earlier. The fluid concrete is then poured into the perimeter foundations (or other substantially contained volume) and leveled or screeded. The side panels 20 are then “wet set,” in which the interior surface 34 of the side panels 20 are oriented downwardly and pressed firmly into the wet concrete so that a portion of the interior surface 34 of the side panel 20 contacts or is adjacent to the upper surface of the poured concrete. Two men can easily lift each array of panels, which may measure, in an example construction, four feet by twenty feet. In such an example, each array may be formed of panels abutting end to end 28 , 30 and five arrays of side panels 20 may be coupled together top end 24 to bottom end 26 to form a surface that is twenty feet by twenty feet. If necessary, small “fill-in” pieces of the side panels 20 are easily installed by hand after the arrays of panels are positioned. Compared to insulation mounted onto a tilt-up wall after the concrete slab C has cured, these contiguous, interlocked side panels 20 of the present invention provide superior insulation over systems that have breaks (i.e., at the location of a ferring member) and are significantly less expensive to install. In the preferred embodiment, each side panel 20 in the array of panels measures sixteen inches by forty-eight inches (16″×48″) and has thirty (30) attachment points 44 that penetrate into the concrete C forming the tilt-up wall. Thus, there are 5.6 penetrations per square foot of wall surface area. If it is believed that the attachment points 44 will not provide a sufficient bond to the concrete C, then stanchions can be used, which are discussed below and some of which are shown in FIG. 6 . When the side panels 20 are firmly pressed into the wet cement, the attachment points 44 penetrate into the wet concrete. A stinger vibrator (not shown) or the like may also be used on the strongbacks or side panels 20 to aid in the consolidation of the concrete around the attachment points 44 . After setting the side panels 20 , the strongbacks are removed so that the tilt-up system 10 is complete and ready for curing. Once the poured concrete substantially cures and forms a concrete slab C, that slab maintains its relative position against the interior surface 34 of the side panel 20 by the attachment points 44 . That is, by projecting beyond the interior surface 34 of the side panel 20 , the web members 40 anchor the side panel 20 to the concrete slab C so that the concrete slab C and side panel 20 form the tilt-up concrete structure 10 of the present invention. After the concrete slab C is substantially cured, the formed concrete structure 10 is tilted up, as discussed below and shown generally in FIG. 11 . Referring again to FIG. 7 generally illustrating the wet-setting construction method of the tilt-up walls, one skilled in the art will appreciate that this process has specific benefits. First, the side panels 20 that are disposed over the concrete—which may be performed within ten minutes of pouring—can act as a barrier to the ambient environment. The less temperate the ambient conditions, the more beneficial the wet-setting method using the side panels 20 positioned over the wet concrete. For example, in hot conditions, the side panels 20 retard evaporation so that a slower “wet cure” of the concrete occurs and the formed tilt-up wall is stronger based on the curing process. Without using the side panels 20 of the present invention, either the moisture evaporates too quickly resulting in a structurally weaker concrete or, more typically, a sealing membrane or “retardant” is sprayed over the top of the fluid concrete after screeding and leveling—an expense that is not incurred using the wet-setting process of the present invention. Alternatively, if the ambient environment is cold (i.e., close to or below freezing conditions), the side panels 20 also facilitate curing by including an insulating layer. Without using the wet-setting process of the present invention, the prior art techniques have involved using tents with propane blowers, blanketing the top surface of the concrete, or heating the area around the poured tilt-up wall using other means known in the art. The present invention is advantageous because it avoids or reduces the labor, fuel, and equipment costs associated with heating the concrete as it cures. Another advantage of the wet-setting method is that irregularities in the upper surface of the concrete after pouring are acceptable. That is, the poured concrete should be leveled within plus or minus one quarter inch (±¼″) before placing the side panels 20 into the concrete. Accordingly, the process of using a power trowel, which is labor intensive and can be expensive, is most likely avoided. Therefore, the wet-setting method circumvents the need for curing compounds, power trowels or other surface finishing, and curing thermal blankets or other heating processes. For the second method of forming the tilt-up walls shown generally in FIG. 8, the side panel 20 is horizontally-disposed so that the attachment points 44 extend upwardly (i.e., opposite to the orientation of the wet-setting embodiment). The interior surface 34 of the side panel 20 becomes the surface onto which concrete is poured. Perimeter forms (not shown) are placed around the of the periphery, namely, the top end 24 , bottom end 26 , first end 28 , and second end 30 of one side panel 20 or an array of side panels 20 , to prevent the fluid concrete from leaking off of the interior surface 34 . Furthermore, as discussed below if a connector 50 is used as a stanchion instead of other exemplary embodiments shown in FIG. 6, re-bar can be positioned within the apertures 56 to strengthen the tilt-up wall prior to pouring the concrete. Once the concrete is poured, leveled, and substantially cured, the forms are removed and the side panel 20 and substantially cured concrete slab C creates the tilt-up wall 10 . The second method of forming a tilt-up wall advantageously avoids use of a release agent. Also, one skilled in the art will appreciate that the term “a side panel” as used for the second and third designs may encompass multiple panels, including an array of panels discussed above for the first design. The third method or design of forming the tilt-up wall repeats first steps used in the second design, namely, the side panel 20 is horizontally-disposed so that the attachment points 44 extend upwardly; perimeter forms are placed around the of the periphery of the side panel 20 ; and the concrete is poured. However, before the concrete cures to any substantial degree, another, second side panel 20 is wet set into the poured concrete, as occurs in the first design. Thus, the third method is a hybrid of the first two methods to create a wall 10 that, when substantially cured and tilted up, has the design shown in FIG. 2 A. As will be appreciated, the interior surfaces 34 of the opposed side panels 20 and the web members 40 disposed therein are spaced apart in a non-contacting relationship with each other so that the first and second side panels are stationarily positioned relative to each other by only the concrete slab C disposed within the cavity 38 . That is, unlike the first embodiment shown in FIG. 2, there are no connectors 50 or other components interconnecting the opposed side panels 20 . This third method of making a tilt-up wall 10 has many advantages. When considered to prior art tilt-up walls, it encompasses the same advantages of both the first and second methods of forming a tilt-up wall, such as avoiding the need for (1) curing thermal blankets or other heating processes, (2) curing compounds, (3) power trowels or other surface finishing, and (4) a release agent. This third design also has greater insulating value and sound impedance than either of the first two designs since there are side panels 20 on each side of the concrete slab C, instead on only on one side. The third embodiment also has potential advantages over the first embodiment of the present invention, which is shown in FIGS. 1 and 2, particularly if the wall being formed is greater than one story high. Most obviously, this dual-panel tilt-up wall form using the third design does not use connectors so there is a cost savings both by avoiding the purchase of these components and by not requiring the labor to install the connectors to interconnect the side panels. In addition, for a wall greater than one story high, the cost of external bracing and scaffolding during the wall assembly and pouring of concrete is not required. Since the panels 20 are laid flat during pouring of the concrete, there are minimal hydrostatic pressures compared to the panels being erected before pouring. As one skilled in the art will further appreciate, the practice of forming a wall as shown in the first embodiment typically involves filling in the cavities in four foot vertical increments, called lifts. The process of forming each lift is more labor intensive than filling the cavity continuously at a single horizontal location. Furthermore, it is imprudent—and prohibited by some building codes—to drop concrete more than ten feet because the constituents of the concrete tend to separate from each other, resulting in a weak final product. Thus, the usual practice in vertical-wall formation is to cut holes into the side panels at different elevational positions and then patch the holes after they are used as a filling port between the source of concrete and the cavity. This process of using the holes in the side panels, obviously, increases the labor costs and time required to fill the cavity for a wall greater than one story in height. The third design of the tilt-up wall, in comparison, avoids these problems and, accordingly, is quicker and less expensive to construct than the first embodiment of the dual-panel wall for wall structures greater than one story in height. Regardless of the method used to form the tilt-up walls of the present invention, the side panels 20 —either with or without the stanchions connected—forge a bond with the concrete as it cures. Once the concrete C obtains sufficient strength for lifting (usually 2,500-3,000 psi) that is typically reached in five to ten days (depending on ambient conditions), a crane (not shown) or other means connects to cables (not shown) attached to embedded inserts cast into the tilt-up wall. The crane sequentially lifts each tilt-up wall and sets it on a prepared foundation around the building perimeter. FIG. 11 shows a single concrete structure 10 having been tilted up. Before any of the tilt-up walls are released by the crane, temporary braces (not shown) are installed—at least two per tilt-up wall—to brace up the respective tilt-up walls until the roof structure is attached. Next, connections between individual tilt-up walls are made, which usually entail welding splices of steel ledger angles (not shown), and then the joints between the tilt-up walls (typically three-quarter inch (¾″)) are caulked. Also, any necessary patching is made to repair blemishes. Approximately the same time, the closure strip between the tilt-up walls and the floor slab (usually a two-foot-wide strip) is filled with concrete and the bracing is removed when the roof has been permanently connected to the tilt-up walls. One of the advantages of using tilt-up walls 10 of the present invention is the shortened construction time. All of the steps discussed above in forming a building frame, from pouring the floor slab to erecting the tilt-up walls that are ready to receive the roof structure, often require only four weeks. Tilt-up walls are also generally less labor intensive to construct, which results in a financial savings. Moreover, tilt-up walls 10 of the present invention may be used to form multi-story buildings. When considering the benefits of using the side panels 20 with tilt-up walls, one skilled will appreciate the improved insulation and sound impedance that exists using the side panels 20 , which would be difficult and expensive to install on a conventional tilt-up wall once erected. Also, the web members 40 , when set into the concrete and substantially cured, insure a substantially permanent, worry-free connection for the side panels 20 and provide a solid attachment point that may be used to connect wallboard such as sheet rock, brick, or stone finishes. Moreover, electrical and plumbing runs are easily installed within the side panels 20 . That is, installing electrical and plumbing is accomplished by cutting the “run's” using a hot knife, router, or electric chain saw into the side panel 20 of preferred embodiment, which is made of EPS. Also, using the preferred side panels 20 removes any potential metal contact problems and makes it much easier to connect pipes and wires compared to achieving the same with conventional tilt-up walls. The tilt-up wall concrete structure 10 using a side panel 20 on only one side of the concrete slab C can also be used as an insulated concrete floor, in which the panels are formed and raised upwardly to form a floor of the building. Likewise, the structure 10 can also be used to create roof panels. Thus, the present invention can be used to construct the majority of an entire building, namely, the walls, floors/ceilings, and roof panels. Also of note, the side panels 20 do not affect the engineered structural design of the formed tilt-up wall as compared to not using the panels. If the concrete or “slump” is dry or if ambient conditions are cold, the attachment points 44 —being rectangular and substantially flat and extending eleven-sixteenths ({fraction (11/16)}) of an inch from the interior surface 34 of the side panel 20 in the preferred embodiment—may have difficulty penetrating into the fluid concrete. The present invention, as mentioned above, includes stanchions or extending devices that assist in bonding the side panels 20 to the wet concrete. The primary function of the stanchions is to form better bonds between the concrete C and the side panel 20 . As such, the side panels 20 are less likely to separate from the concrete slab C of the tilt-up wall or other wall of the present invention throughout its life. A secondary function of the stanchions is to give greater structural integrity to the side panels 20 and associated wallboard, brick, or stone finishes attached to the end plates 42 of the web members 40 . That is, by being more firmly anchored, the concrete slab C provides a better connection to the side panels 20 and a stronger foundation for any materials hung from the side panels 20 . The stanchions are discussed in the specific context of a tilt-up wall but, as one skilled in the art will appreciate, the stanchions, for example, may also be useful in a dual-panel wall discussed above to buttress the connection between the side panel 20 and the concrete poured into the cavity 38 . One specific embodiment of the stanchion comprises a connector 50 , for example, coupled to one attachment point 44 to increase the surface area to which the concrete C bonds. If the connectors 50 are the incorrect length, then they can easily be cut to the proper dimension at the construction site. The connectors 50 , as discussed above, are best shown in FIGS. 4 and 4A. Two additional such stanchions are shown in FIG. 6, namely, an extender 60 and a tilt-up anchor 70 . First addressing the extender 60 , it includes a tip end 62 , an opposed base end 64 , and a body 66 extending therebetween. Preferably, the tip end 62 is of a size to complementarily engage one end 52 of a connector 50 and the base end 64 is of a size to complementarily engage one attachment point 44 . Similar to the preferred designs discussed above, the tip end 62 is preferably rectangular in plan view—as is the attachment point 44 —and the base end 64 preferably defines a track of a size to slidably receive a selected one of the tip end 62 or the attachment point 44 therein—as does one end 52 of the connector 50 . The locking means is preferably also part of the extender 60 and other stanchions. The body 66 of the extender 60 is preferably non-smooth, which assists in bonding to concrete C. In the preferred embodiment, the body 66 defines a passage 68 therethrough. As will be noted by FIGS. 6 and 12, the passage 68 has a substantially rectangular cross-section. In the preferred embodiment, the width of the sides of the passage 68 is between one-quarter (¼) and one (1) inch to have a cross-sectional area between approximately 0.125 and 1 square inches, and more preferably between one-half (½) inch and three-quarter (¾) inch to have a cross-sectional area between approximately 0.25 and 0.57 square inches. This range of widths allows a portion of a flexible linking member 90 (shown in FIG. 12) to be received therethrough (as discussed below) as well as being of a dimension to allow fluid concrete to at least partially flow into the passage 68 for better bonding. Of course, other dimensions are contemplated to achieve these same functions and, in fact, the minimal dimension to allow fluid concrete to flow partially therein may be a function of the viscosity of the fluid concrete and size of the aggregate stone used. Likewise, other cross-sectional shapes for the passage 68 are also contemplated, such as circular, elliptical, triangular, or other polygonal shapes. As one skilled in the art will also appreciate, the body 66 of the extender 60 can be manufactured in different lengths, depending on the use of the extender 60 ; however, the preferred length between the tip end 62 and the base end 64 is approximately one inch. Three functions of the extender 60 of the present invention are addressed herein: (1) as a stanchion; (2) as an extension for the connectors 50 ; and (3) as part of a connection between side panels 20 or to buttress the connection between panels 20 . The first listed function of extender 60 is the same as the other stanchions, which is to provide an additional surface to which the concrete can bond while curing to form a stronger connection with the side panel 20 . The extender 60 connects to one respective attachment point 44 of the web member 40 and extends into the concrete C a greater distance than the attachment point 44 . This longer extension, in and of itself, strengthens the bond between the concrete C and the side panel 20 to which the extender 60 is connected since there is more surface area to which the concrete C may bond during curing. Moreover, this bond is further strengthened by the extender 60 in the preferred embodiment having a non-smooth surface and, in the preferred embodiment, the non-smooth surface resulting in part from the passage 68 extending therethrough. As mentioned above, the passage 68 is preferably of a dimension to allow fluid concrete to at least partially flow therein, which enhances the bond with concrete C. The second listed function of the extender 60 is to extend the reach of the connectors 50 . As discussed above, it is preferred to make the connectors 50 having lengths so that the width of the cavity 38 is two (2), four (4), six (6), eight (8) inches or greater. If, however, it is desired to have the width of the cavity 38 be three (3), five (5), or seven (7) inches, then the preferred embodiment of the extender 60 could be used to obtain that extra inch of separation. Assume, for example, that the connector 50 shown in FIGS. 4 and 4A connects to the two attachment points 44 of opposed side panels 20 in the dual-panel embodiment (which is discussed above and shown in FIGS. 1 and 2) to form a cavity 38 that is two inches wide. To increase the width of the cavity 38 to be three inches wide, the preferred extender 60 is used in conjunction with the connector 50 shown in FIG. 4 or FIG. 4 A. That is, the tip end 62 of the extender 60 is preferably formed to be the same dimensions as an attachment point 44 of the web member 40 so that the tip end 62 can be slidably received into the track 54 at one end 52 of the connector 50 , similar to the attachment point 44 being slidably received into the end 52 of the connector 50 . The base end 64 of the extender 60 , in conjunction, preferably forms a track into which one attachment point 44 of a web member 40 is slidably received (i.e., the same dimension as the track 54 of the connector 50 shown in FIG. 4 or FIG. 4 A). Accordingly, the connector 50 is coupled to the attachment point 44 of one side panel 20 , the base end 64 of the extender 60 is coupled to the attachment point 44 of the opposed side panel 20 , and the connector 50 is attached to the tip end 62 of the extender 60 so that a three-inch wide cavity 38 is formed between two opposed side panels 20 , instead of a two-inch cavity if the connector 50 shown in FIG. 4 or FIG. 4A was used alone. Thus, in the preferred embodiment, for each extender 60 added between the connector 50 and the attachment point 44 , the extender 60 advantageously allows the cavity 38 to be extended one inch in width. As such, the extender 60 can be used to meet this need to have an irregularly sized cavity without requiring the manufacturer to mold special new connectors, which would be an expensive endeavor. As one skilled in the art will appreciate, the extender 60 can have a length other than one inch, if desired. The third potential function of the extender 60 is to establish or to buttress the connection between side panels 20 . One example in which the extender 60 is beneficial when one wall or panel is at a non-parallel angle to another wall or panel, often being disposed at right angles to form a T-wall in top plan view, which is shown in FIG. 13 . Since concrete has to be poured into the cavity 38 defined by the side panels 20 that are not oriented parallel to each other (as exists in FIG. 2 ), the normally linear connectors 50 shown in FIGS. 4 and 4A cannot feasibly be used. As one skilled in the art will appreciate, although within the scope of the present invention, manufacturing non-linear connectors would be expensive and often not be viable for a large percentage of construction projects. In conjunction, one problem with constructing such a T-wall is that when the concrete is poured into the cavity 38 , pressures against the abutting side panel 20 (i.e., at the top of the “T”) forces the side panel outwardly. The prior art solution is to brace the wall on the exterior surface 32 of the side panel 20 using, for example, lumber braces. The braces, however, are difficult and labor intensive to construct, particularly when used on multistory building above the first or ground floor. Referring now to FIG. 12, the extender 60 , used with a flexible linking member 90 , such as a zip-tie, plastic tie strap, tie wire, or other similar component, provides an easy and effective solution to buttress a connection between side panels 20 , particularly for situations in which the respective interior surfaces 34 are not parallel to each other. Although not required, it is preferred that the flexible linking member 90 be contiguous and connect to itself in by forming a closed loop, in which the looped linking member 90 interconnects the opposed side panels 20 . For one design shown at the top of FIG. 12, respective extenders 60 are connected to attachment points 44 formed on different side panels 20 . That is, in this design there are two extenders: a first extender 60 connected to the attachment point 44 of one web member 40 partially disposed within a first panel 20 and a second extender 60 connected to the attachment point 44 of one web member 40 partially disposed within the opposed second panel 20 . A portion of the flexible linking member 90 , in conjunction, traverses through the passage of the first extender 60 and a portion of the flexible linking member 90 also traverses through the passage of the second extender 60 . The flexible linking member 90 is connected through the respective passages of two extenders 60 and tightened, thereby securely interconnecting the spaced-apart panels 20 . In another embodiment, it is also contemplated that at least one of the two web members 40 defines a slot 41 extending therethrough. The slot 41 is preferably located adjacent the interior surface 34 of the first panel in which the web member 40 is disposed and preferably integrally formed with the web member 40 . The slot 41 is also preferably of a size to receive a portion of the flexible linking member 90 therein. Thus, as shown at the bottom of FIG. 12, a portion of the flexible linking member 90 traverses through the slot 41 of one web member 40 and also traverses through the extender 60 connected to the attachment point 44 of the other web member 40 to interconnect the spaced-apart panels 20 . In still another embodiment shown at the middle of FIG. 12, a portion of the flexible linking member 90 traverses through the slot 41 of one web member 40 and the slot 41 of the other web member 40 to interconnect the spaced-apart panels 20 . The three illustrated embodiments shown in FIG. 12, of course, may be used independently of each other. Similarly, the extender 60 with the flexible linking members 90 can be used anywhere on the side panels 20 where there may be weakness in the structure. As an example, weakness may exist where a cut-up design is used or the wall zig-zags. As another example, weakness may also occur wherever quick turns are used in the layout of the side panel 20 . In these situations, the extenders 60 and interconnecting flexible linking members 90 may be used in lieu of external bracing. Although not preferred, it is also contemplated that the flexible linking member 90 —in concert with the passages 68 of extenders 60 or the slots 41 formed into the web members 40 —may interconnect opposed side panels 20 in the first embodiment (shown, for example, in FIGS. 1 and 2 ), instead of using connectors 50 to interconnect the side panels 20 . In comparison to the extender 60 , another design of the stanchion, the anchor 70 , is also shown in FIG. 6 and is less broad in its potential functional uses. The primary purpose of the anchor 70 is to strengthen the bond between the side panel 20 and the adjacent concrete once that concrete has substantially cured. The preferred anchor 70 has a forward end 72 , an opposed back end 74 , and a body 76 extending therebetween. The back end 74 is preferably of a size to complementarily engage one attachment point 44 . Also, it is preferred that the body 76 has at least one prong 78 extending from it and, more preferably, two prongs 78 oriented co-linearly to each other. However, as one skilled in the art will appreciate, other permutations also fall within the scope of the present invention, such as three or more prongs 78 or two prongs 78 not oriented co-linearly. The presently preferred prongs 78 have a length of a half (½) inch to one (1) inch and a generally round cross-sectional shape that has a diameter of one quarter (¼) inch. One skilled in the art, however, will appreciate that wider range of values are possible for the prongs 78 —the important consideration being that the prongs 78 not break when fluid concrete flows past the anchor 70 during the construction process or after substantial curing. Also, the prongs 78 can be integrally formed to the anchor 70 or coupled thereto using any means known in the art. Returning to the presently preferred embodiment of two co-linear prongs 78 , it is preferred that when the anchor 70 is connected to the attachment point 44 , the two prongs 78 form an angle that is not perpendicular or normal to a plane formed by the interior surface 34 of the side panel 20 (and also the plane formed by the exterior surface of the concrete C on the tilt-up wall). In fact, it is most preferred that the two prongs 78 extend parallel to the plane formed by the interior surface 34 of the side panel 20 to which the anchor 70 is attached, an angle which is generally perpendicular to the direction that the anchor 70 extends between its forward and back ends 72 , 74 when connected to the attachment point 44 . This angular orientation of the prongs 78 provides increased bonding strength with the concrete C. Although it is presently preferred that there is at least one prong 78 , the present invention contemplates that no prongs be included; instead, the body 76 of the anchor 70 can be of a non-smooth or non-linear shape to bond with the fluid concrete that flows around the body 76 . One contemplated design includes a generally mushroom shape that is narrow at the back end 74 and flares outwardly moving toward the forward end 72 . Other contemplated designs include the forward and back ends 72 , 74 being wider in side view than the intervening portion of the body 76 so that the body appears similar to a chef's hat or an hourglass in side view. Of course, symmetry is not required in any of these alternative embodiments. As one skilled in the art will appreciate, one important consideration is that the fluid concrete be able to flow around the anchor 70 to improve bonding after the concrete substantially cures. Although the length of the connector 50 , extender 60 , or anchor 70 used as a stanchion between the interior surface 34 of the side panel 20 and the tip of the stanchion may be any dimension shorter than the thickness of the concrete portion of the tilt-up wall, the preferred embodiment uses a length of one inch (1″) or less. The reason for using a length shorter than the possible maximum length is that a longer stanchion would potentially interface with the re-bar or other structural support within the tilt-up wall. That is, either by convention or as required by applicable building code requirements, the re-bar is usually placed one inch or more away from either surface of the tilt-up wall so that the ends of the respective stanchions, extending the maximum of one inch, will not interface with or contact the re-bar, which could impede the proper setting of the side panels 20 into the fluid concrete. As with the connectors 50 , the other embodiments of the stanchions are preferably formed of a high-density plastic, such as high-density polyethylene or polypropylene, although other polymers can be used as noted above. Advantages of the high-density plastics for the stanchions include cost of manufacturing, strength, rigidity when the component is sufficiently thick, and the like. As one skilled in the art will also appreciate, the stanchions are not necessary for the present invention to function and, in fact, may not even be desired if the concrete is very “wet” or a plasticizer has been added to the concrete in the context of constructing tilt-up walls. If stanchions are used, it is contemplated using one stanchion per web member 40 connected to the center attachment point 44 (i.e., the middle attachment point 44 shown in FIG. 6 ); however, it is also contemplated using up to and including one stanchion on each attachment point 44 (i.e., five stanchions used on every web member in the embodiment shown in FIG. 6 ). Referring now to FIGS. 9 and 9A, the third embodiment of the present invention is analogous to the first embodiment because a cavity is formed into which concrete is poured. However, instead of the formed concrete structure having opposed side panels 20 each connected to the concrete portion as in the first embodiment shown in FIGS. 2 and 2A, this embodiment preferably uses a side panel 20 on only one side of the formed concrete structure 10 . That is, the formed concrete structure 10 is similar to the tilt-up wall discussed above (i.e., a concrete slab C with side panels 20 positioned only on one side), but is made using a different construction process. More specifically and as best shown in FIG. 9, the third embodiment uses a side panel 20 and an opposed sheet 80 to form the cavity 38 into which the concrete is poured. That is, in forming the wall 10 , the process involves positioning the side panel 20 and the sheet 80 substantially upright so that a portion of the interior surface 34 of the side panel 20 faces a portion of an inside surface 82 of the sheet 80 . The interior surface 34 and the inside surface 82 are laterally spaced apart from each other so that a cavity 38 is formed therebetween, just as occurs in the first embodiment using spaced-apart side panels 20 . The sheet 80 is preferably plywood, but can be any solid material that can be coupled to either a web member 40 or a connector 50 and can withstand the forces exerted by the fluid concrete when poured into the cavity 38 without substantial bowing, warping, breaking, or other type of failure. Other contemplated materials include combined steel frame and plywood center, commonly known as a steel-ply panel. Accordingly, the sheet 80 functions as a form or barrier while the concrete is curing. The process next involves attaching one end 52 (“the first end”) of the connector 50 to the attachment point 44 of the side panel 20 and connecting a portion of the inside surface 82 of the sheet 80 to the other end 52 (“the second end”) of the connector 50 . However, it may be a matter of preference for the order of construction so the first end of the connector 50 may be attached to the attachment point 44 before positioning the sheet 80 or the sheet may be positioned before the first end of the connector 50 is attached to the attachment point 44 . The sheet 80 can be either directly or indirectly coupled to the connector 50 . That is, referring back to FIG. 3, there are two options for the second or “free end” of the connector 50 , which is the end not attached to the web member 40 located within the side panel 20 . First, for the indirect connection and as shown in FIG. 9, the free end can be connected to, for example, a stand-alone web member 40 ′, which is a web member that is not formed within a side panel 20 and is illustrated in FIGS. 3, 6 , 9 , and 10 . The sheet 80 is then connected to the end plate 42 of the stand-alone web member 40 ′, instead of being directly connected to the second end of the connector. This indirect connection forms the preferred embodiment. FIG. 3 shows only one stand-alone web member 40 ′ that is attached to the connectors 50 . As one skilled in the art will appreciate, however, multiple web members 40 are preferably used when preparing the wall structure 10 (i.e., between two and six stand-alone web members 40 ′ used for the side panel 20 shown in FIG. 3 based on there being six web members 40 located within the side panel 20 ). It is, of course, preferred to use a sufficient number of web members to withstand the dynamic and static forces that exist when the fluid concrete is poured into the cavity (i.e., preferably six for the side panel 20 shown in FIGS. 3 and 9 ). Alternatively and less preferred, the sheet 80 may be connected directly to the second or free end of the connector 50 . Still referring to FIG. 3, four connectors 50 are shown in this configuration (i.e., connected to the web member 40 located within the side panel 20 but not connected to a stand-alone web member 40 ′). Thus, unlike the indirect connection having an intervening stand-alone web member 40 ′ or other component, the sheet 80 in this design is directly coupled to the second ends of the connectors 50 . The potential drawback with this design is that it is more difficult to attach or couple the sheet 80 to the connectors 50 at the construction site. However, if the free end of the connectors 50 is formed with more surface area than included in the illustrated embodiments, this potential drawback may be reduced. It is also contemplated using connectors 50 that are integrally attached to or formed with the web members 40 located in the side panels 20 for the third embodiment (as well as other embodiments). Stated differently, the connectors 50 and web members 40 may be a unitary structure and, as such, the attachment points 44 in this contemplated design extend a distance from the interior surface 34 of the side panel 20 to the attachment points 44 that is substantially equivalent to the desired thickness of the cavity 38 for the direct connection process. Thus, the step of attaching the connectors 50 to the attachment points 44 of the web members 40 disposed within the side panels 20 is avoided because the inside surface 82 of the sheet 80 is attached directly to the attachment point 44 to form the cavity 38 . Alternatively, the extended attachment points 44 may be designed to connect to the stand-alone web member 40 ′ or similar structure is using the indirect connection method. However, this design of integrally forming the connectors 50 to the attachment points 44 has a potential drawback of the increased space needed to transport a given quantity of side panels 20 to the construction site if the web members 40 are integrally formed into the side panels 20 , as opposed to being inserted through precut slots at the construction site. Regardless of the component to which the sheet 80 is connected, it is preferred that the sheet be detachably connected, or removably attached, to the second end of the connector 50 or stand-alone web member 40 ′. By being detachably connected, the present invention entails that the sheet 80 can be removed from the end plate 42 or connector 50 substantially intact, preferably so that the sheet can be reused to form another concrete structure. Many means are contemplated for detachably coupling the sheet 80 to the end plate 42 or connector 50 , such as using a nail or screw. One skilled in the art will appreciate that this list is not exhaustive and can include other coupling means such as chemical adhesives, rivets, tacks, nuts and bolts, and the like. Once the sheet 80 and side panel 20 are interconnected and stationarily positioned relative to each other, the process of forming the structure 10 involves pouring fluid concrete into the cavity 38 and allowing the concrete to substantially cure to form a concrete slab C. The formed concrete structure 10 is shown in FIG. 9 A. In the preferred embodiment, after the concrete substantially cures (which may take about three days depending on ambient conditions and the thickness of the cavity 38 ) the process involves removing the sheet 80 from the concrete slab C to expose a portion of the concrete slab C to atmosphere, which is shown in FIG. 11 . That is, after substantially curing, the sheet 80 is preferably removed leaving a concrete structure 10 that has a side panel 20 disposed on one side and concrete C exposed to ambient or atmosphere on the other, opposed side. The sheet 80 is also preferably reusable for forming another wall. However, although not preferred, it is contemplated having the sheet 80 remain a permanent part of the tilt-up structure 10 as shown in FIG. 9 A. A potential aesthetic drawback with the above process is that when the sheet 80 is removed, the exposed surface will be predominately concrete C with the end plates 42 or the ends 52 of the connectors 50 recurrently showing on the exposed concrete surface. To avoid this non-contiguous appearance and as shown in FIG. 10, the present invention also contemplates using a spacer 84 attached or permanently affixed to the end plate 42 of the stand-alone web member 40 ′ or to one end 52 —the free or second end—of the connectors 50 . The spacer 84 is to be disposed in a contacting relationship with the inside surface 82 of the sheet 80 . Referring now to FIG. 10, one embodiment of the spacer 84 is cone-shaped in side view, in which the narrow end is attached or coupled to the end plate 42 of the stand-alone web member 40 ′ or the end 52 of the connector 50 and preferably extends between a quarter and three-quarter (¼-¾) inches, more preferably one-half (½) inch. The cone-shaped spacers may also be inverted so that the wide end is attached to the end plate 42 . It is also contemplated that the cone-shaped spacer 84 has openings or slots extending between the narrow end and the wide end. Other shapes are contemplated for the spacer 84 , such as circular, elliptical, or rectangular shapes in plan view. It is also contemplated having the spacer 84 use a constant cross-sectional area along its length, instead of being cone shaped. The sheet 80 is mounted to abut the wide end of the spacer 84 and the screw—if used as the coupling means—traverses through the sheet 80 , spacer 84 , and then into and through a portion of either the end plate 42 of the stand-alone web member 40 ′ or end 52 of the connector 50 . If the wide end of the spacer 84 is attached to the end plate 42 , then the coupling means need not traverse through the interior of the spacer, which may be easier at the construction site because less precise aligning is required. If the spacer 84 has openings, at least some concrete may enter into its internal volume when the cavity 38 is filled with concrete. Using the spacers 84 , after the concrete substantially cures and the sheet 80 is removed, the interior volume of the spacer 84 is exposed so that there are only small portions of the concrete surface in which the concrete C is not contiguous on the face of the structure 10 . However, since the preferred spacer 84 is cone-shaped, a finish coat of cementitious material, including concrete, a parging coat, or stucco, can quickly be spread into the interior volume of the spacers so that when it cures, the exposed face of the concrete structure 10 appears as a uniform concrete surface, as opposed to having the ends 52 of the connectors 50 or the end plates 42 exposed. One skilled in the art will appreciate that a uniform concrete appearance obtained using the spacers 84 is more aesthetically appealing if the exposed surface of the concrete structure remains exposed when the building is completed. However, if it is desired to mount materials such as drywall or masonry tiles directly onto the surface originally covered by the sheet 80 , not using the spacers 84 may be preferred. That is, the exposed end plates 42 of the stand-alone web members 40 ′ or the ends 52 of the connectors 50 facilitate attaching materials to the concrete surface because it is easier to connect materials to these members, compared to attaching the materials to the cured concrete C. Also, if the entire exposed concrete surface will be coated with stucco or the like, then depending on the bonding properties of the coating, it may be irrelevant whether the spacers 84 are used. Although the present invention has been described with reference to specific details of certain embodiments thereof, it is not intended that such details should be regarded as limitations upon the scope of the invention except as and to the extent that they are included in the accompanying claims.

A concrete structure formed using an extender that connects to a web member at least partially disposed within a side panel. The extender may be used to extend the length of a connector that interconnects opposed side panels, used to provide additional surface area to which concrete can bond if, for example, forming a tilt-up wall, or used as a strapping location with a flexible linking member. It is noted that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to ascertain quickly the subject matter of the technical disclosure. The abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims pursuant to 37 C.F.R. §1.72(b).

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a downhole tool for enhancing the force of a downhole jarring tool. More particularly, the present invention relates to a downhole tool capable of enhancing an upward jarring blow or a downward jarring blow emanated from a double acting hydraulic well jar useful in coiled tubing and conventional drilling applications. 2. Description of the Related Art Jarring tools are used to free stuck drill pipe or well tools in a well bore. They provide a substantial upward or downward jarring action in an effort to transmit sufficient force to dislodge a stuck member. Double acting jars which can transmit either upward or downward jarring loads are well known in the prior art. See, for example, U.S. Pat. Nos. 4,186,807; 4,865,125; and 5,007,479. Such jars typically use a hydraulic-type fluid to isolate well bore pressure and provide the working fluid through which the jarring tool operates. It may also be helpful to employ a downhole tool proximate the jarring tool which serves to enhance or accentuate the force exerted by the jarring tool on the stuck tool in either the upward jarring mode or the downward jarring mode. Typically, such tools serve to accelerate the rate at which the hammer of a jarring tool strikes the anvil or other portion which generates the jarring action. Examples of enhancers or accelerators are set forth in U.S. Pat. Nos. 3,735,828; 4,846,237; 5,232,060; 5,425,430; and 5,584,353. With the advent of coiled tubing techniques, the need exists for a variety of downhole tools capable of performing their traditional functions but in the confines of a coiled tubing application. Briefly, a coiled tubing operation involves the use of a single continuous pipe or tubing for drilling or workover applications rather than the more traditional 30-foot drill pipe sections. The tubing, which is coiled onto a reel and uncoiled as it is lowered into the well bore, can be used for either drilling or workover applications. However, coiled tubing presents a number of working constraints to existing tool design. First, due to the size of the coiled tubing, limited compressive and tensile loads can be placed on the tubing by the rig operator. Essentially, this means that downhole tools which require tensile or compressive force to operate, such as a jarring tool, must be capable of operating with the limited compressive load capability of coiled tubing. In addition, in coiled tubing application the overall length of the downhole tool becomes significant since there is limited distance available between the stuffing box and the blowout preventor to accommodate the bottom hole assembly. A typical bottom hole assembly includes a quick disconnect, an enhancer or accelerating tool, a sinker bar located below the enhancer to provide weight to the bottom hole assembly, the jarring tool, a release tool below that of some type, and then an overshot. There may be other tools as well which may be needed. Thus, the length of the jarring tool enhancer becomes particularly significant since the entire bottom hole assembly must fit within the limited distance between the riser and blowout preventor to introduce it into a pressurized well. Furthermore, within these confines, the jarring tool enhancer must have a large enough internal bore to permit pump-down tools to pass. Thus, the coiled tubing jarring tool enhancer must have a limited overall wall thickness in view of limited outer diameter conditions, and must be of limited length. As in the case of traditional drill pipe, coiled tubing or other down hole tools may get stuck in the well bore at times. Under these circumstances, the ability to generate an enhanced load through a mechanism which accelerates the jarring motion of the jarring tool and introduces an auxiliary force is particularly advantageous. Thus, the need exists for a jarring tool enhancer which can satisfy the limited load, limited length, and large bore requirements of coiled tubing application as mentioned above. Preferably, such a jarring tool enhancer would have application in a conventional drill string as well. SUMMARY OF THE INVENTION Briefly, the present invention is a well jar enhancer having inner and outer overlapping, telescopingly related cylindrical assemblies or tubular members which move longitudinally relative to one another. Because of their overlapping nature, an annular space or chamber is formed between the inner and outer cylindrical assemblies. Longitudinal splines are provided on both cylindrical assemblies which are slidably engaged in an interlocking fit to permit relative longitudinal movement yet prevent relative rotational movement. Upper and lower annular seals are preferably provided which seal off the annular space from the well bore. A sealing piston is positioned within the annular space and adapted for longitudinal displacement therein. The inner assembly includes a member which contacts the piston as the inner assembly moves relative to the outer assembly in a first direction thereby defining a first chamber between the first sealing means and the piston and a second chamber between the second sealing means and the piston. The outer assembly includes a member to prohibit longitudinal movement of the piston within the annular space beyond a predetermined point when the inner assembly moves relative to the outer assembly in a second direction, thereby defining another first chamber between the first sealing means and the piston and another second chamber between the second sealing means and the piston. The present invention permits telescopic movement of the inner cylindrical assembly relative to the outer cylindrical assembly in either the first or second direction wherein displacement of the piston relative to the outer assembly in the first direction and displacement of the piston relative to the inner cylindrical assembly in said second direction creates a pressure differential between the first and second chambers permitting acceleration of the outer cylindrical assembly relative to the inner cylindrical assembly to balance the pressures in the said first and second chambers at a predetermined time for each said first and second directions. The inner and outer cylindrical assembly of the present invention are each comprised of multiple tubular elements which, in the event of separation between adjacent tubular elements due to pressure build up or loads for example, will interlock to avoid separation of the drill string or coiled tubing. While the present invention has been described in terms of a coiled tubing application principally, it should be understood that the elements of the present invention have equal application as a jarring tool enhancer for use with a jarring tool to free stuck conventional drill strings and downhole tools. Examples of the more important features of this invention have been summarized rather broadly in order that the detailed description may be better understood. There are, of course, additional features of the invention which will be described hereinafter and which will also form the subject of the claims appended hereto. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A-1C are detailed fragmented vertical cross-sectional views of the present invention in a neutral position. FIGS. 2A-2C are detailed fragmented vertical cross-sectional views of the present invention in a partially open position. FIGS. 3A-3C are detailed fragmented vertical cross-sectional views of the present invention a substantially fully opened position. FIGS. 4A-4C are detailed fragmented vertical cross-sectional views of the present invention in a partially closed position. FIGS. 5A-5C are detailed fragmented vertical cross-sectional views of the present invention in a closed position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1A-1C, the present invention comprises an outer cylindrical assembly or tubular member 20 and an inner cylindrical assembly or tubular member 22. Typically, outer cylindrical assembly or tubular member 20 comprises a mandrel body 24 threadably connected to a spline body 26. Spline body 26 is in turn threadably connected to middle body 28 which is threadably connected to washpipe body 30. Typically, inner cylindrical assembly or tubular member 22 comprises a mandrel 32 threadably connected to mandrel extension 34. Mandrel extension 34 is in turn threadably connected to washpipe 36. Threaded connections 71, 72, 73, 74 and 75 typically include one or two o-rings within each connection to create a sealed connection across the threads thereby preventing pressure loss. Referring still to FIGS. 1A-1C, inner cylindrical assembly 22 is positioned within outer cylindrical assembly 20 in a telescoping fashion defining an annular space 38 which is sealed at the top or upper end thereof by a seal 40 and at the bottom or lower end thereof by a seal 42. In this manner, any hydraulic fluid or other medium within chamber 38 is isolated from the effects of hydrostatic pressure or well bore pressure. Chamber 38 may be filled with hydraulic fluid through fill outlet 44. A threadable plug (not shown) would be inserted within fill 44 to seal off chamber 38. The type of hydraulic fluid or other fluid which could be used in annular chamber 38 is well known to those skilled in the art and may be, for example, a hydraulic fluid, preferably a synthetic silicone liquid which is slightly more compressive than standard hydraulic oil. Preferably, the synthetic silicone liquid is in the range of approximately 8% to 12% compressible. Referring to FIGS. 1A and 1B, mandrel 32 includes circumferentially spaced splines 46. Similarly, spline body 26 includes similarly circumferentially spaced splines 48 within region "A" of spline body 26. Splines 48 of spline body 26 interlock in a meshing manner with splines 46 of mandrel 32. In this manner, longitudinal movement of outer cylindrical assembly 20 relative to inner cylindrical assembly 22 is permitted but relative rotational movement between outer cylindrical assembly 20 and inner cylindrical assembly 22 is prohibited. Thus, any torquing, or motor drilling or rotary drilling activity may continue to occur through the jarring tool enhancer. Referring now to FIG. 1C, the present invention also includes a piston 50 which is longitudinally positioned within annular chamber 38. Piston 50 includes an internal seal member 52 which seals against the outer surface of mandrel extension 34. Similarly, piston 50 includes an outer seal 54 which seals against the inner surface of middle body 28. In this manner, it will be apparent to one skilled in the art that piston 50 is capable of dividing chamber 38 into two distinct pressure chambers. The first chamber 56 would extend between top or upper seal 40 to piston 50 while a second chamber 58 would extend from bottom or lower seal 42 to piston 50. Referring briefly to FIG. 1A, a mandrel retainer ring 60 is positioned circumferentially around mandrel 32 to help centralize mandrel 32 within outer cylindrical assembly 20, and in particular blind body 26. Mandrel retainer 60 is not a seal; rather, it serves primarily to retain mandrel 32 within outer cylindrical assembly 20. Thus, fluid may pass easily through mandrel retainer 60 permitting chamber 56 to extend from top seal 40 to piston 50. Referring now to FIGS. 1A-1C, 2A-2C and 3A-3C, the operation of the present invention will be described. In particular, the operation of the present invention as it moves from a relatively neutral position as shown in FIGS. 1A-1C to a fully opened position as shown in FIGS. 3A-3C will be described. In the position shown in FIGS. 1A-1C, piston 50 is seated against both the top shoulder 62 of washpipe 36 and the top shoulder 64 of washpipe body 30. At this point, the pressure in chambers 56 and 58 are substantially balanced. As noted above, the present invention is used to provide an enhanced or auxiliary acceleration of the hammer portion of a jarring tool against the anvil portion of the jarring tool. Such a jarring tool must be suitable for coiled tubing application as well and would be typically located in the bottom hole assembly below the present invention. Such a jarring tool suitable for use with the present invention is described and claimed in copending patent application Ser. No. 08/827,794 entitled JARRING TOOL, which patent application is hereby incorporated by reference and made a part hereof. The movement shown in FIGS. 1A-1C, 2A-2C and 3A-3C of the present invention are movements in an upward direction toward the ground surface, which coincide with an upward jarring action as referred to in the above-identified copending patent application. As noted in the copending patent application and discussed above, a drilling rig operator has a limited compressive load capability when using coiled tubing. Thus, the use of a jarring tool enhancer to accelerate the jarring action of a jarring tool as discussed in the copending application is particularly helpful. Referring now to FIGS. 2A-2C, the rig operator begins an upward jarring action by introducing a tensile load on the coiled tubing or drill string which advances inner cylindrical assembly 22 in the direction of arrow 66. As inner cylindrical assembly 22 moves upwardly relative to outer cylindrical assembly 20, shoulder 62 of washpipe 36 pushes piston 50 upwardly increasing the volume or size of chamber 58 and reducing, in turn, the volume or size of chamber 56. Since the amount of hydraulic fluid within annular space 38 is limited due to the use of a top seal 40 and the lower seal 42, a pressure differential is created between chambers 56 and 58. In the case of FIG. 2C, in essence a vacuum is created in chamber 58. As the rig operator continues to introduce a tensile load on inner cylindrical assembly 22, a jarring tool such as that disclosed in the above-identified copending patent application would also advance into an upward jarring configuration as shown in FIGS. 8A-8C of the copending patent application. As the rig operator continues to introduce a tensile load in the direction of arrow 66 there would be an increase in the relative longitudinal position between inner cylindrical assembly 22 relative to outer cylindrical assembly 20 as shown in FIGS. 3A-3C. In this configuration, shoulder 62 of washpipe 36 continues to move piston 50 upwardly increasing the volume of chamber 58 and decreasing the volume of chamber 56 thereby creating a larger pressure differential across piston 50. FIGS. 3A-3C show the fully opened position when ring 60 has seated against the lower shoulder 59 of mandrel body 24. If a jarring tool is used as that described and claimed in the above-identified copending application, eventually an upward jarring activity would be triggered as that shown in the transition from FIGS. 8A-8C to 9A-9C of the above-identified copending patent application. For example, once the hammer of a jarring tool is released advancing towards an upward jarring position as shown in FIGS. 9A-9C of the above-identified copending patent application, there would be a sudden movement of outer cylindrical assembly 20 relative to inner cylindrical assembly 22 of the present invention. This sudden upward movement releases stored energy within the present invention because of the significant pressure differential between chambers 56 and 58. This sudden release serves to further accelerate the hammer of a jarring tool against the anvil of the jarring tool as described and shown, for example, in FIGS. 9A-9C of the above-identified copending patent application. This energy is eventually dissipated as the pressures between chambers 56 and 58 are balanced which occurs when outer cylindrical assembly 20 moves upwardly relative to inner cylindrical assembly 22 returning the present invention to the neutral position as shown in FIGS. 1A-1C. In the event the rig operator wished to repeat the upward jarring action, he would simply repeat the process referred to above with respect to FIGS. 1A-1C, 2A-2C and 3A-3C. In addition to the upward jarring motion as described above, the present invention is also capable of enhancing a jarring action in a downward mode. Referring now to FIGS. 4A-4C and 5A-5C, the rig operator begins by introducing a slightly compressive load in the direction of arrow 68 as shown in FIG. 4A. Doing so advances inner cylindrical assembly 22 downwardly relative to outer cylindrical assembly 20. When this occurs, piston 50 is prohibited from moving longitudinally relative to outer cylindrical assembly 20 and in particular middle body 28 and washpipe body 30 because shoulder 64 of washpipe body 36 seats against piston 50 preventing it from moving downwardly as inner cylindrical assembly 22, and in particular mandrel extension 34, moves downwardly. As this occurs, the volume or size of chamber 58 increases and the volume or size of chamber 56 decreases. This in turn results in a pressure differential between chambers 56 and 58 and the creation, once again, of a vacuum in chamber 58 relative to chamber 56. As the operator continues to introduce a compressive load in the direction of arrow 66 as shown in FIG. 4A, the corresponding jarring tool as described and claimed in the above-identified copending application, for example, would enter the operational mode as shown in FIGS. 10A-10C and 11A-11C of that copending application. FIGS. 5A-5C show the final closed position of the present invention as the rig operator continues to exert a downward load in the direction of arrow 68 as shown in FIG. 4A but before the downward jarring action has occurred. Eventually, as described in the copending application, the jarring tool would initiate a downward jarring activity which, for purposes of the present invention, would result in the sudden movement of outer cylindrical assembly 20 relative to inner cylindrical assembly 22, and in particular, the sudden movement of mandrel extension 34 relative to middle body 28. This sudden movement or release of energy occurs because of the pressure differential between chambers 56 and 58. In this manner, this sudden relative movement between the inner and outer cylindrical assemblies 22/20 serves to accelerate the movement of a hammer towards an anvil of the jarring tool as described and shown in FIGS. 12A-12C of the above-identified copending application for example. If the rig operator wished to exert another downward jarring action using the present invention, he would repeat the cycle referred to above with respect to FIGS. 4A-4C and 5A-5C as often as he wished to continue to create an enhanced or accelerated effect to the hammer and anvil of the jarring tool. It will be apparent to one skilled in the art that it is not necessary for the rig operator to take the present invention to the fully opened or fully closed positions as shown in FIGS. 3A-3C or FIGS. 5A-5C, respectively. Rather, the present invention may serve as an enhancer without the need to be fully opened or fully closed. As described above, precisely when the energy stored within the enhancer and the drill string would be released would be determined by the tripping of the jar tool as described in the copending application, for example. It will also be understood by one skilled in the art that the present invention is not limited to an operation in the orientation as shown in FIGS. 1A-1C. Obviously, the present invention may be turned upside down and it will still perform equally well. To that extent, the terms "upward" and "downward" as used herein are with reference to the orientation shown in FIGS. 1A-1C, for example. Additionally, it will be apparent to one skilled in the art based on this disclosure that the description and claiming of the present invention in terms of permitting rapid acceleration of outer cylindrical assembly 20 relative to inner cylindrical assembly 22 also means rapid acceleration of inner cylindrical assembly 22 relative to outer cylindrical assembly 20. These operational terms are deemed to be equivalent for purposes of the present invention and the claims as attached hereto. The present invention also provides an enhanced safety feature in the event a threaded joint of either the inner or outer cylindrical assemblies separate. This may occur due to significant pressure increases, material fatigue or excessive loading, for example. Referring back to FIGS. 1A-1C, the key joints of concern from a safety standpoint are threaded connection 71 between mandrel body 24 and spline body 26, threaded connection 72 between spline body 26 and middle body 28, and threaded connection 73 between mandrel 32 and mandrel extension 34. In the event the rig operator is exerting an upward tensile load 66 as shown in FIG. 3A or a downward compressive load 68 as shown in FIG. 4A and threaded connection 71 fails, box connection 76 of mandrel extension 34 will advance upwardly with reference to FIG. 1B forcibly engaging splines 48 in region "A" of spline body 26. This forcible engagement would prevent further displacement of inner cylindrical assembly 22 relative to outer cylindrical assembly 20 thereby preventing loss of the lower part of the coiled tubing, drill pipe or tool downhole or other catastrophic event. This safety feature occurs whether a compressive or tensile load is being applied to the mandrel 32 by the rig operator. Furthermore, in the event threaded section 72 separates, the present invention provides that piston 50 would advance upwardly rapidly relative to outer cylindrical assembly 20 until it forceably engages the thickened upset wall portion of middle body 28 as shown by region "B" of FIG. 1B. This thickened wall portion (region "B") of middle body 28 is thin enough to permit passage of splines 46 when operating in a normal mode, but gradually increases in thickness from the lower to the upper end to stop the advancement of piston 50 in the event of a catastrophic failure of thread 72. In this manner, once again loss of the lower part of the coiled tubing, drill pipe, downhole tool or portion of the bottom hole assembly would be prevented whether the failure occurred when the rig operator was applying a tensile or compressive load. Finally, in the event of a catastrophic failure of threads 73, the present invention prevents the loss of outer cylindrical assembly 20 and the rest of the bottom hole assembly because mandrel retainer ring 60 would advance upwardly towards mandrel body 24 forceably engaging mandrel body 24 and thereby forceably interlocking with it. Once again this will occur whether the rig operator is applying a tensile or compressive load. Accordingly, the present invention provides a jarring tool enhancer of limited lengths due to the use of a single annular chamber 38 which can be divided into upper and lower chambers 56/58 depending on whether the operator introduces a compressive or tensile load. The present invention also uses a single piston within that single annular chamber further reducing the overall length of the present invention. This simplified design has significant advantages because of its limited length, particularly in coiled tubing application. Yet it still performs as a jarring tool enhancer providing a significant increase in the jarring load on the stuck tool through its rapid acceleration of the inner cylindrical assembly 22 relative to the outer cylindrical assembly 20. The foregoing invention has been described in terms of various embodiments. Modifications and alterations to these embodiments will be apparent to those skilled in the art in view of this disclosure. It is, therefore, intended that all such equivalent modifications and variations fall within the spirit and scope of the present invention as claimed below.

A dual acting hydraulic jarring enhancer which is particularly well suited for coiled tubing application. A common annular chamber is formed between reciprocating cylindrical assemblies, and a piston is positioned within the annular chamber. The inner cylindrical assembly has a member to contact the piston and move it relative to the outer cylindrical assembly in one direction while the outer cylindrical assembly has a member to prohibit longitudinal movement of the piston relative to the inner cylindrical assembly in a second direction. In this manner, the present invention provides a tool with overall minimal length by using a singular annular chamber capable of being divided into two other chambers and providing an accelerating effect to a hammer/anvil of an associated jarring tool in either an upjarring or downjarring mode.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention pertains to the field of viscous petroleum recovery. 2. Description of the Prior Art This invention is an improved method for the recovery of oil from subterranean hydrocarbon bearing formations wherein the oil is very viscous, that is, it has a low API gravity or is a bitumen. This method is especially useful for recovering hydrocarbons from reservoirs such as tar sand formations. The recovery of very viscous oil from formations and bitumens from tar sands has generally been difficult if not impossible on a commercial scale. Although some advances have been realized in recent years in stimulating the recovery of heavy oils, i.e., oils having an API gravity in the range of 10° to 25° API, little success has been realized in recovering bitumens from tar sands. Bitumens are generally regarded as being highly viscous oils having a gravity in the range of about 4° to 10° API and are contained in an essentially unconsolidated sand referred to as a tar sand. Vast quantities of tar sand exists in the Athabasca region of Alberta, Canada. Although these deposits contain several hundred billion barrels of oil or bitumen, the recovery of this bitumen using conventional in situ techniques has been less than successful. The reasons for this lack of success relates primarily to the fact that bitumen is extremely viscous at the temperature of the formation with consequently low mobility. In fact, the bitumen is so viscous that it appears to be a soft solid. In addition, these tar sand formations have very low permeability even though they are unconsolidated. Using the principal that the viscosity of oil decreases with an increase in temperature, prior art techniques have usually been designed with the idea of raising the temperature of the bitumen in situ. This improves its mobility and therefore its amenability to recovery. These thermal recovery techniques generally include steam injection and hot water injection as well as in situ combustion. Usually these techniques employ an injection well and a production well spaced apart from each other and penetrating an oil bearing formation. In the usual steam operation involving two wells, the steam is introduced into the formation through the injection well and the heat from the steam is transferred to the bitumen (if a tar sand is involved) thus lowering its viscosity and therefore improving mobility while the flow of the hot fluid in the injection well drives the bitumen toward the production well from which it may be produced. Normally, in an in situ combustion operation, an oxygen containing gas, such as air is introduced into the formation through an injection well and combustion of the in place crude adjacent to the well bore is initiated by one of many known means such as the use of a downhole gas fired heater or a downhole electric heater or in some cases chemical means. Thereafter, the injection of oxygen containing gas is continued to maintain a combustion front which is formed, and to drive the front through the formation toward the production well. Ideally, as the combustion front advances through the formation, a swept area is formed consisting of a clean sand matrix behind the front. Ahead of the advancing front various contiguous zones are formed and are also displaced ahead of the combustion front. These zones may be envisioned as a distillation and cracking zone near the front, a vaporization and condensation zone farther from the front, an oil bank even farther from the front, and lastly an unaltered zone. The temperature at the combustion front is generally very high ranging from 650° to 1200° F. The heat thus generated in this zone is transferred to the distillation and cracking zone just ahead of the combustion front where the crude or bitumen undergoes some distillation and cracking. In this zone a sharp thermal gradient is thought to exist wherein the temperature drops from the temperature of the combustion front to about 300° to 450° F. As the front progresses through the formation, the temperature of the formation continues to rise and the heavier molecular weight hydrocarbons of the oil become carbonized and are deposited on the matrix of the formation. These carbonized hydrocarbons are the potential fuels to sustain the progressive in situ combustion zone. Ahead of the distillation and cracking zone is a vaporization and condensation zone. This zone is a thermal plateau and its temperature is in the range of from about 200° to about 450° F depending upon the distillation characteristics of the fluid in the formation and the formation pressure. These fluids consist of water and steam and hydrocarbon components of the crude or bitumen. Ahead of the vaporization and condensation zone is an oil bank which fills up as the in situ combustion front progresses and the formation of crude is displaced toward the production well. This zone is highly oil saturated but contains not only reservoir fluids but also condensate, cracked hydrocarbons and gases which are products of combustion which eventually reach the production well from which they may be produced. Although in situ combustion has been used to increase recovery of bitumen and viscous crudes, variations of the technique have taken place in order to improve its performance, for example, water or saturated steam is sometimes injected with the air. See for example, U.S. Pat. No. 2,584,606. This is sometimes referred to as wet combustion. This has improved the process somewhat. However, the method has several weaknesses which will limit the process to only a very few reservoirs. It has been found, for example, that the wet process is restricted to relatively heavy crudes containing very high molecular weight hydrocarbons, thick reservoirs and very close well spacing, which contribute to very high costs. In addition, U.S. Pat. No. 2,839,141 suggests that super heated steam injection and in situ combustion with super heated steam is a way to displace heavy oils. However, this method also has limitations. Even though it conducts a great deal of heat initially into the formation, it connot displace all of the oil in the swept zone and since the super heated zone cannot propagate over great distances from the well bore, it also requires close well spacing. Laboratory models utilizing simultaneous injection of super heated steam and air have recovered over half of the bitumen in place. Although these results are an improvement over the simple wet in situ combustion, it has the same limitations as the separate method, that is, it leaves behind in the swept zone a significant quantity of combustible material. There is always a significant degree of vertical permeability, variation especially in tar sand reservoirs, which causes the thermal front to migrate through only a portion of the oil saturated interval. As a result heat loss is high which prevents the thermal front from propagating at great distances from the injection well. In the case of in situ combustion, the combustion front will finally cease when the vertical combustion interval narrows down to about 4 feet. Our invention proposes a method which will be an improvement over prior art methods in that it will eliminate many of the disadvantages which render them ineffective in some cases. The objectives of our invention are to increase the distances of the propagation of very high temperature fronts thereby reducing the necessity for a large number of wells, to increase the efficiency of the thermal method and to increase the thermal conformance in both the vertical and horizontal planes. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts the leading edge of saturated steam as distance from a well bore. FIG. 2 shows the thermal effect on the formation of injecting super heated steam only. FIG. 3 shows the effect of super heated steam followed by super heated steam plus air. FIG. 4 shows the effect of using a saturated steam followed by saturated steam plus air. SUMMARY OF THE INVENTION The invention is a method for recovering hydrocarbons such as low gravity viscous crude oil or bitumen from a subterranean reservoir penetrated by at least one injection well and at least one production well comprising the steps of: a. injecting super heated steam into the formation via said injection well, b. terminating injection of said super heated steam and initiating injection of air to establish an in situ combustion front in said reservoir, c. continuing injection of said air to support the in situ combustion front and resuming injection of super heated steam at the said injection well, d. terminating injection of said super heated steam and initiating injection of water along with the air to continue an in situ combustion front, e. terminating air injection to discontinue the in situ combustion front while continuing to inject water into said injection well and f. producing said hydrocarbons from said production well. DESCRIPTION OF THE PREFERRED EMBODIMENTS In one embodiment of our invention, an in situ combustion operation using super heated steam and air procedes an in situ combustion operation using water and/or saturated steam. In another embodiment of our invention, an in situ combustion operation precedes injection of super heated steam and an in situ combustion operation using water and/or saturated steam. In other embodiments of our invention, the above embodiments are terminated using a final sweep of water to scavenge heat from the formation. The term air used herein is used for convenience and includes not only air comprising mainly nitrogen and oxygen but any oxygen containing gas which may be used. The most preferred method of our invention involves several steps which comprise the following: 1. Super heated steam injection; 2. Air injection (in situ combustion); 3. Simultaneous super heated steam and air injection (in situ combustion); 4. Simultaneous air (in situ combustion) and water injection; and 5. Water injection. The method of our invention including all of the steps in order listed above is superior to any of the steps taken singly or in lesser combination. Utilizing a computational model and computer program we will demonstrate the technical superiority of our method. Table I below lists the reservoir injection data that were used in the computational model. TABLE I______________________________________Reservoir DataFormation thickness 26 ft.Thermal capacity 35 BTU/ft..sup.3 ° FThermal conductivity 1 BTU/hr. ft. ° FAPI gravity of crude oil 18.6°Initial reservoir temperature 80° FKh 1.1 darcy - ft.Distance between injection well andproducing well (in an inverted 5 spot) 320 ft.Injection DataInjection pressure 500 psigProducing well pressure 200 psig(1) Superheated steam injection rate 400 B/D at 700° F(2) Superheated steam injection + air injection:Steam at 400 B/D at 700° FAir at 1.84 MMSCF/D(3) Hot water injection + air injectionHot water at 400 B/D at 200° FAir at 1.84 MMSCF/D______________________________________ Computations may best be displayed by the graphical representations FIGS. 1-4. FIG. 1 shows the leading edge of the saturated steam zone as distance from the injection well versus time. Curve 1 of FIG. 1 represents super heated steam alone. The curve 2 segment is for super heated steam plus air from 72 to 144 days of the operation. Curve 3 is for super heated steam and air or air and 200° F water injection after 144 days have elapsed. It is noted that the introduction of the situ combustion speeds up the advance of the thermal front. Combination of in situ combustion with super heated steam drastically increases the velocity of the thermal front which increases oil and production rates and recovery. A distinct advantage is obtained by augmenting super heated steam with in situ combustion. All oil bearing formations have a vertical permeability distribution. Therefore, injected fluids traverse through only a minor portion of the vertical interval taking the path of least resistance. The oil bearing beds adjacent to the invaded thermal zones are heated, however, and a substantial amount of oil is produced therefrom. Heat transport from the hot zone to the cooler uninvaded zone varies directly with the temperature of the hot zone, the areal extent of the hot zone and the time of the uninvaded zone's exposure to the hot zone. The dramatic increase in thermal front advance rate as shown by Curve 3 over Curve 1 of FIG. 1 is evident. FIG. 2 shows the computer calculation of a temperature profile from the injection well to a production well 320 feet apart. After 360 days of injecting super heated steam at 700° F, formation is heated to that value (700° F) for only a short distance from the injection well. A rather long saturated steam temperature plateau is established, however, the formation is heated only halfway to the production well. FIG. 3 is also a plotted temperature profile for 360 days of thermal drive. For this case, however, 72 days of super heated steam injection was followed by super heated steam plus air injection for another 288 days for a total of 360 days as in FIG. 2. A study of FIG. 3 discloses that a much higher thermal front advance rate has been obtained over that of FIG. 2 which was for super heated steam along. Also, much more heat is introduced into the formation. This is determined by intergration of the curve. Also a much higher temperature differenc (Delta T) over a greater aerial extent exists. The higher thermal front advance rate and the greater amount of heat in the formation increase oil production rate and recovery directly. The great difficulty in propagating any thermal front in a piston-like manner makes the higher Delta T extremely effective in heating, moving and recovering oil in the adjacent uninvaded oil saturated bed. The superiority over the simple wet combustion process which consists of in situ combustion followed by in situ combustion and water injection is proven by comparing the results on FIG. 3 with the results on FIG. 4. Although the advance rate of the saturated steam front is the same for the wet combustion process, the amount of heat in the formation and aerial extent of a very high temperature gradient between swept and unswept zones are much higher for the process of FIG. 3 than for the wet combustion process (FIG. 4). This increases oil recovery and production rate in the case of our process. In addition to the above features, displaying advantages over the wet combustion process, pretreating with super heated steam injection will convert many formations from non-combustible to formations which will initiate and propagate an in situ combustion front. The super heated steam will open up at larger vertical intervals for burning and store up adequate heat in the formation for good propagation of the combustion during the earlier stages of the project which is very critical to success. Fuel studies using in situ combustion after injection of 80% quality steam have shown that considerable extraneous heat had to be supplied along with the air in order to ignite the formation. In fact the temperature near the injection well bore actually decreased during the early phase of hot air injection. Having water in the formation much heat was utilized in vaporizing the water which is necessary prior to combustion. Our process eliminates this detrimental feature by vaporizing all water near the well bore with super heated steam initially having the formation very dry, combustion is assured not only in the most receptive but also in less permeable sections. Thus, our method is also superior to simultaneous super heated steam and air injection alone for the following reasons: 1. Higher temperatures are attained; 2. Higher temperature gradients are achieved; 3. Heat transport to the formation is high; and 4. More of the original combustible material is utilized for increasing rate and recovery.

A method for recovering low gravity viscous crude oil or bitumen from a subterranean formation comprising first injecting super heated steam, next initiating an in situ combustion by injecting air, followed by an in situ combustion wherein both super heated steam and air are injected, then simultaneously performing an in situ combustion by injecting air while also injecting water and finally injecting water.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to submersible pump installations for wells and to a safety system which maintains the well under control. 2. Description of the Prior Art In some hydrocarbon producing formations, sufficient reservoir pressure may be present to cause formation fluids to flow to the well surface. However, the hydrocarbon flow resulting from the natural reservoir pressure may be significantly lower than the desired flow. For these types of wells, electrically powered submersible pumps are sometimes installed to achieve the desired hydrocarbon flow rate. Submersible pumps can be used to raise various liquids to the well surface. Examples of prior art submersible pump and safety valve installations are shown in U.S. Pat. Nos. 3,853,430; 4,121,659; 4,128,127 and 4,134,454. Copending U.S. patent applications Ser. No. 186,980 filed Sept. 15, 1980 and Ser. No. 306,035 filed June 7, 1982 disclose improved safety systems for use with submersible pumps. The preceding patents and patent applications are incorporated by reference for all purposes within this application. SUMMARY OF THE INVENTION The present invention discloses a well completion having a submersible pump with an intake and a discharge disposed within a well flow conductor comprising packer means for forming a fluid seal with the interior of the flow conductor at a downhole location to direct fluid flow to the pump intake; a landing nipple releasably secured to the upper portion of the packer means; a longitudinal passageway extending through the landing nipple; a safety valve releasably secured within the longitudinal passageway for controlling fluid flow therethrough; means for attaching the submersible pump to the landing nipple above the safety valve; and the longitudinal passageway providing a portion of the means for directing fluid flow to the pump intake. One object of the invention is to provide a submersible pump installation having a safety system including a subsurface safety valve which is controlled by hydraulic pressure from the pump discharge. Another object of the invention is to provide a landing nipple for installing a submersible pump and a safety valve at a downhole location. The submersible pump, safety valve, and landing nipple are retrievable from within the flow conductor. The safety valve blocks fluid flow to the well surface when the submersible pump is not operating and when the submersible pump has been retrieved from the landing nipple. A further object of the invention is to provide a submersible pump installation including a universal landing nipple in which various submersible pumps and safety valves can be mounted. A still further object of the invention is to provide a landing nipple which can be releasably secured to various well packers. Additional objects and advantages of the invention will be readily apparent to those skilled in the art from reading the following description in conjunction with the drawings and claims. BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B are schematic views partially in longitudinal section and partially in elevation showing a well completion with a submersible pump and safety system of the present invention FIGS. 2A-J are partially in section and partially in elevation showing the submersible pump attachments and safety system of FIG. 1 disposed within a casing string. The safety system is shown in its first or closed position blocking fluid flow through the packer mandrel. FIG. 3 is an enlarged drawing in longitudinal section showing the engagement between the pump seating mandrel and the landing nipple of the present invention. FIG. 4 is an enlarged drawing in longitudinal section showing the engagement between the landing nipple and the well packer. FIGS. 5A-D are drawings in longitudinal half-section with portions broken away showing the safety system of FIG. 1 in its second or open position allowing fluid flow through the flow conductor. FIG. 6 is a drawing in horizontal section taken along line 6--6 of FIG. 2C. FIGURE 7 is a drawing in horizontal section taken along line 7--7 of FIG. 3. FIG. 8 is a drawing in horizontal section taken along line 8--8 of FIG. 4. DESCRIPTION OF THE PREFERRED EMBODIMENTS A submersible pump installation and safety system incorporating the present invention are schematically illustrated in FIGS. 1A and 1B. Well 20 is partially defined by casing or flow conductor 21 which extends from wellhead 25 to a producing formation (not shown). Couplings 21a are used to connect the joints of casing 21 with each other. Well packer means 23 with packer bore 24 extending therethrough forms a fluid barrier with the interior of casing 21 to direct fluid flow from the producing formation to the well surface via packer bore 24. Valve 26 controls production fluid flow from wellhead 25 into surface flowline 27. To increase production fluid flow, submersible pump P is shown suspended within flow conductor 21 by electrical cable C. Pump P is driven by electrical motor 28 to discharge formation fluids from outlets or discharge ports 22 into the bore of casing 21 above packer 23. Accumulator means 30 is attached to and extends downwardly from pump inlet 32. Preferably, travel joint 50 is attached below accumulator means 30. Pump support means or seating mandrel 33 is attached below travel joint 50. The weight of pump P, motor 28, accumulator means 30 and travel joint 50 is supported partially by the contact between seating mandrel 33 and landing nipple 40 and partially by cable C. Cable C also supplies electrical power from the well surface to motor 28. Wellhead 25 includes packing means 34 which forms a fluid barrier around cable C and prevents undesired fluid flow therepast. Pump P, motor 28, and cable C are commercially available from various companies. One such company is REDA Pump Division of TRW in Bartlesville, Okla. Bore 43 extends longitudinally through pump inlet 32, accumulator means 30, swivel connector means 29, travel joint 50 and pump seating mandrel 33. Bore 43 provides a flow path for formation fluids to enter pump P. Bore 43 is given an alphabetic designation within each component attached to pump P to aid in describing the invention. As shown in FIGS. 2A-2D, appropriately sized o-rings are included within each connection between the various components attached to pump P to prevent undesired fluid communication between bore 43 and the exterior of the components. Pump inlet 32 is attached by bolted connection 38 to accumulator 30 as shown in FIG. 2A. One advantage of the present invention is that various submersible pumps can be attached to inlet 32 and satisfactorily installed within casing 21. Also, the components of the submersible pump installation could be connected to each other by means other than bolted connections 38. The total length of the submersible pump installation including motor 28, pump P, accumulator means 30, travel joint 50 and seating mandrel 33 requires the use of swivel connector means 29 between various components. Swivel connector means 29 compensate for deviations of casing 21 while raising and lowering pump P and attached components. Swivel connector means 29 may also be classified as a flexible joint or articulated joint. Installing several swivel connector means 29 allows limited flexing of the components relative to each other while installing and retrieving pump P. However, swivel connector means 29 are designed to prevent rotation of the components attached thereto relative to each other. Swivel connector means 29 allows accumulator means 30 and travel joint 50 to flex relative to each other in one plane as determined by keys 48 and keyways 49. In the same manner, a swivel connector means 29 is preferably installed between travel joint 50 and seating mandrel 33 as shown in FIGS. 2C and 2D. When pump P is turned off, safety valve S will close. Accumulator means 30 communicates with pump inlet 32 to supply a reservoir of fluid to allow discharge pressure from pump P to open safety valve S when pump P is turned on. Swivel connector means 29 allows the attachment of as many accumulator means 30 as required for each submersible pump installation. In FIG. 1A, only one accumulator means 30 is shown, but others may be added as desired. Travel joint 50 comprises primarily two long, hollow cylinders 51 and 52. Cylinder 51 is sized to telescope within cylinder 52. Keyways 53 are machined longitudinally into the exterior of cylinder 51. Matching keys 54 are carried by cylinder 52 and slide longitudinally in keyways 53. Keys 54 and keyways 53 cooperate to prevent rotation of cylinders 51 and 52 with respect to each other. Packing means 55 is carried on cylinder 51 near its extreme end disposed within cylinder 52. Packing means 55 forms a fluid barrier with the adjacent inside diameter of cylinder 52 as cylinders 51 and 52 telescope longitudinally relative to each other. Travel joint 50 is preferably installed with cylinder 51 telescoped approximately 50% into cylinder 52. This results in cable C carrying the weight of pump P and the components above cylinder 51. This weight maintains cable C taut without overstressing it. The weight of cylinder 52 and the components therebelow is supported by contact between seating mandrel 33 and landing nipple 40. The extreme ends of travel joint 50 have appropriate bolted connections 38 for attachment to adjacent components. Seating mandrel 33, attached to travel joint 50 by a swivel connector means 29, is a relatively short hollow cylinder with bore 43e extending therethrough. Packing means 79 are carried on the exterior of seating mandrel 33 below keyways 80. Packing means 79 are sized to form a fluid barrier with inside diameter 81 of landing nipple 40. Packing means 79 blocks fluid discharged from pump outlets 22 from flowing downwardly through longitudinal passageway 41 of landing nipple 40. A plurality of keyways 80 extend longitudinally through a portion of the exterior of seating mandrel 33. Matching keys 78 project radially inward from the interior of longitudinal passageway 41 and engage keyways 80. Keys 78 and keyways 80 cooperate to prevent rotation of seating mandrel 33 and landing nipple 40 relative to each other. Various mechanisms other than keys 78 and keyways 80 could be used to secure seating mandrel 33 within landing nipple 40 and prevent rotation of the components relative to each other. U.S. patent application Ser. No. 199,034 filed on Oct. 20, 1980 and U.S. Pat. No. 4,121,659 disclose such mechanisms. For ease of manufacture and assembly, landing nipple 40 has an upper section 40a, a middle section 40b and a lower section 40c threadedly engaged to each other. Upper section 40a and middle section 40b comprise tubular housing means with longitudinal passageway 41 extending therethrough. Section 40a is engaged with section 40b by threads 42 as shown in FIG. 2H. Upper section 40a is shown as a relatively long piece to accommodate both pump seating mandrel 33 and safety valve S. If desired, upper section 40a could be manufactured from several shorter hollow tubular sections with appropriate threaded connections to engage the shorter tubular sections with each other. Lower section 40c is an adapter sub engaged to middle section 40b by threads 82 as shown in FIGS. 2H and 4. Longitudinal passageway 41 extends through lower section 40c and communicates with well packer bore 24. A portion of the outside diameter of lower section 40c is sized to be received within upper portion 156 of well packer 23. Collet assembly 45 on lower section 40c provides means for releasably securing landing nipple 40 with well packer 23 to allow fluid communication between longitudinal passageway 41 and packer bore 24. End 46 of upper section 40a (the other end of landing nipple 40 opposite from collet assembly 45) is sized to receive seating mandrel 33 partially into longitudinal passageway 41. The portion of longitudinal passageway 41 adjacent to the other end 46 has first inside diameter 60 larger than the inside diameter of the remainder of longitudinal passageway 41. Seating shoulder 44 is formed on the interior of longitudinal passageway 41 by the transition between the inside diameters thereof. Keys 78 project radially inward from first inside diameter portion 60. Honed sealing surface 81 is provided on the interior of longitudinal passageway 41 adjacent to seating shoulder 44. When keys 78 are engaged with keyways 80 and pump seating mandrel 33 is resting on seating shoulder 44, packing means 79 forms a fluid barrier with honed surface 81. A set of locking grooves 84 is machined in the interior of longitudinal passageway 41 in nipple section 40a below shoulder 44 to provide part of the means for installing safety valve S within landing nipple 40. U.S. Pat. No. 3,208,531 to J. W. Tamplen discloses a locking mandrel and running tool which can be used to install safety valve S within landing nipple 40. As best shown in FIG. 2H, middle section 40b is preferably a heavy, thick walled tubular housing means. The extra weight of this section assists in engaging landing nipple 40 with well packer 23. A portion of middle section 40b and all of lower section 40c are sized to fit within the upper portion of packer bore 24. Tapered surface 146 on the exterior of middle section 40b is formed by the major change in outside diameter of middle section 40b. Packing means 62 are carried on the portion of middle section 40b which fits within packer bore 24. Packing means 62 forms a fluid barrier with the interior of well packer 23 adjacent thereto. Lower section or adapter sub 40c is attached to middle section 40b by threads 82. Collet assembly 45 carried near the extreme end of adapter sub 40c provides means for releasably locking adapter sub 40c to well packer 23. The releasable locking means includes flexible collet fingers 63 formed in the exterior of adapter sub 40c by longitudinal slots 64 as best shown in FIG. 4. Bosses 65 project radially outward from each collet finger 63 intermediate the ends thereof. Bosses 65 are sized to engage annular groove 166 within packer bore 24. Sleeve 67 is slidably disposed within adapter sub 40c. Sleeve 67 has a first position which prevents fingers 63 from flexing and a second position which allows fingers 63 to flex radially inward to release landing nipple 40 from well packer 23. Sleeve 67 has a plurality of collet fingers 172 formed through its exterior similar to collet fingers 63. Bosses 173 project radially outward from each collet finger 172 intermediate the ends thereof. The first position of sleeve 67 is defined by bosses 173 engaging annular groove 171 formed on the interior of longitudinal passageway 41. The second position of sleeve 67 is defined by bosses 173 engaging annular groove 170 formed on the interior of longitudinal passageway 41. Annular groove 170 is located above collet fingers 63 such that when sleeve 67 is engaged with annular groove 170, collet fingers 63 are free to flex radially inward. Conventional wireline techniques and tools can be used to shift sleeve 67 between its first and second position. Port means 89 extend radially through upper section 40a intermediate the ends thereof. The longitudinal spacing of port means 89 relative to locking grooves 84 is selected to allow fluid communication between the exterior of landing nipple 40 and safety valve S installed within longitudinal passageway 41. Fluid pressure from pump discharge ports 22 is communicated with port means 89 via the annulus formed by the interior of casing 21 and the exterior of landing nipple 40. Preferably, well packer 23 and the components attached thereto are located within casing 21 such that a liquid level is always maintained above discharge ports 22. This liquid level is required for satisfactory operation of safety valve S. Locking mandrel 90 carries dogs 91 which coact with grooves 84 to anchor safety valve S within longitudinal passageway 41. Sealing means 92 are carried on the exterior of locking mandrel 90 to form a first fluid barrier with the inside diameter of nipple section 40a when dogs 91 are secured within grooves 84. Equalizing assembly 93 is attached to locking mandrel 90. Sealing means 95 are carried on the exterior of equalizing assembly 93 to form a second fluid barrier with the inside diameter of nipple section 40a. Sealing means 92 and 95 are spaced longitudinally from each other. Valve housing means 96 is engaged by threads 97 to equalizing assembly 93. Sealing means 98 are carried on the exterior of housing means 96 to form a third fluid barrier with the interior of nipple section 40a. Safety valve S includes locking mandrel 90, equalizing assembly 93, valve housing means 96 and the valve components disposed therein. Bore 100 extends longitudinally through safety valve S. Sealing means 92 and 98 cooperate to direct formation fluid flow through bore 100 and block fluid flow between the exterior of valve S and the interior of nipple 40. When the submersible pump installation is operating normally, formation fluids flow from perforations (not shown) into pump P via packer bore 24, longitudinal passageway 41, bore 100, and bore 43. Valve housing means 96 consists of several concentric, hollow sleeves which are connected by threads to each other. Each housing means subassembly has an alphabetic designation. Hydraulically actuated means 101 comprising operating sleeve 102 and piston 103 are slidably disposed within bore 100. Increasing fluid pressure in variable volume chamber 104 will cause operating sleeve 102 to slide longitudinally relative to housing means 96. Inner cylinder 105, which has two subsections designated 105a and 105b, of poppet valve means 106 abuts the extreme end of operating sleeve 102 at 107. Elastomeric seal 108 is carried on the exterior of inner cylinder 105 intermediate the ends thereof. Metal seating surface 109 is provided on the interior of housing means 96 facing elastomeric seal 108. A plurality of openings 110 extends radially through inner cylinder section 105a. Another plurality of openings 111 extends radially through housing subassembly 96c. When safety valve S is in its first position as shown in FIG. 2F, elastomeric seal 108 contacts metal seating surface 109 blocking fluid communication through openings 110 and 111. When operating sleeve 102 slides longitudinally in one direction, it will contact inner cylinder 105 and displace elastomeric seal 108 away from metal seating surface 109. This displacement allows fluid communication through openings 110 and 111 as shown in FIG. 5C. Spring 112 disposed between shoulder 113 on the exterior of inner cylinder section 105b and shoulder 114 of housing means 96 urges elastomeric seal 108 to contact metal seating surface 109. Poppet valve means 106 is included within safety valve S because openings 110 and 111 have a large flow area as compared to bore 100. Also, poppet valve means 106 is easily pressure balanced so that less control fluid pressure is required to displace elastomeric seal 108 away from metal seating surface 109 as compared to opening a ball type valve. Ball valve means 117 is disposed within safety valve S below poppet valve means 106. Operating sleeve 118 of ball valve means 117 is spaced longitudinally away from inner cylinder section 105b when poppet valve means 106 is closed. When piston 103 shifts poppet valve means 106 to its open position, inner cylinder section 105b will contact operating sleeve 118 to rotate ball 119 to align bore 149 of ball 119 with bore 100 as shown in FIG. 5D. Ball valve means 117 is open when bore 149 is aligned with bore 100. Ball valve means 117 is shut when bore 149 is rotated normal to bore 100. Spring 120 urges ball 119 to rotate to block bore 100 when fluid pressure is released from variable volume chamber 104. Ball valve means 117 is a normally closed safety valve which is opened by inner cylinder section 105b of poppet valve means 106 contacting operating sleeve 118. Both poppet valve means 106 and ball valve means 117 operate in substantially the same manner as other surface controlled subsurface safety valves. Control fluid pressure is applied to piston 103 to shift safety valve S to its second or open position. When control fluid pressure is released from variable volume chamber 104, springs 112 and 120 cooperate to return safety valve S to its first or closed position blocking fluid flow through bore 100. As will be explained later, control fluid pressure acting on piston means 103 is supplied from the discharge of pump P. Since inner cylinder section 105b is spaced longitudinally from operating sleeve 118 when safety valve S is in its first position, poppet valve means 106 will open first when pump P is started. Well fluids will initially flow into bore 100 above ball 119 through openings 110 and 111 to equalize any pressure difference across ball 119 and to supply well fluids to pump inlet 32. Thus, accumulator means 30 must contain at least enough fluid to open poppet valve means 106. Also, equalizing the pressure difference across ball 119 prior to rotating ball 119 significantly reduces the force required to open ball valve means 117 and minimizes the possibility of damage to safety valve S. If desired, a flapper valve could be substituted for ball valve means 117. Copending U.S. patent application Ser. No. 186,980 filed on Sept. 15, 1980 fully explains the operation of safety valve S. Equalizing assembly 93 is positioned within safety valve S between locking mandrel 90 and valve housing means 96. Equalizing assembly 93 provides means for selectively equalizing fluid pressure between bore 100 and the exterior of safety valve S while installing and removing safety valve S from longitudinal passageway 41. A plurality of apertures 130 extend radially through equalizing assembly 93. Sliding sleeve 131 with a pair of o-ring seals 132 carried on its exterior is disposed within equalizing assembly 93. 0-ring seals 132 are spaced from each other so that when sleeve 131 is in its first or upper position, o-ring seals 132 will straddle apertures 130 blocking fluid flow therethrough. Collet fingers 133 are carried by sleeve 131 to engage groove 134 and hold sleeve 131 in its first position. Various wireline tools are commercially available which can be lowered from the well surface through casing 21, after pump P has been removed, to shift sleeve 131 to either open or block apertures 130. Longitudinal flow path 86 is provided in the exterior of landing nipple 40 to communicate well fluids from below sealing means 98 to equalizing assembly 93. Radial port 135 extends from longitudinal passageway 41 through nipple 40 to the upper end of longitudinal flow path 86. Radial port 135 is positioned adjacent to apertures 130 between sealing means 92 and 95. Therefore, control fluid or pump discharge fluid is blocked by sealing means 95 from communicating with longitudinal flow path 86. The lower end of longitudinal flow path 86 communicates with longitudinal passageway 41 below packing means 98 through openings 145. A wide variety of commercially available production well packers can be used with the present invention. The only requirement is that the upper portion of the well packer must be modified to allow releasably securing landing nipple 40 therein. Well packer means 23 as shown in FIGS. 1B, 2I and 2J is set by a commercially available electric setting gun and can be retrieved from its downhole location if desired. Packers set by other techniques and permanently set packers may also be used. The various components which comprise well packer means 23 are carried by and assembled on packer mandrel 150. Packer bore 24 extends longitudinally through packer mandrel 150. Slip elements 151 and 152 are slidably disposed on the exterior of packer mandrel 150 with packing elements 153 therebetween. Well packer means 23 is installed at the desired downhole location within flow conductor 21 by radially expanding slip elements 151 and 152 to cause teeth 154 on the exterior of each slip element to bite into the interior of flow conductor 21 adjacent thereto. Packing means 153 is also compressed and radially expanded to form a fluid barrier between the exterior of packer mandrel 150 and the interior of flow conductor 21. Internal slip segments 155 hold slip elements 151 and 152 and packing means 153 in their radially expanded or set position. Upper portion 156 of well packer means 23 comprises an extension of packer mandrel 150 with packer bore 24 extending therethrough. Upper portion 156 could be engaged by threads 157 to the packer mandrel of various commercially available production well packers. Inside diameter 158 of packer bore 24 within upper portion 156 is enlarged to receive the lower end of landing nipple 40 or lower section 40c therein. A plurality of keys 159 projects radially inward from inside diameter 158 to engage matching keyways 160 in the exterior of lower section 40c. Shoulder 161 is formed on the interior of packer bore 24 by the transition from inside diameter 158 to reduced inside diameter 162 of upper portion 156. Inside diameter 158 preferably has a honed sealing surface adjacent to keys 159 to form a fluid barrier with packing means 62 on the exterior of landing nipple 40. Groove 166 is formed within inside diameter 162 to receive bosses 65 of collet assembly 45 therein. Torque generated by electrical pump P is transmitted from pump seating mandrel 33 via keys 78 and keyways 80 to landing nipple 40. From landing nipple 40 the torque is transmitted to well packer 23 via keys 159 and keyways 160. The engagement of slip elements 151 and 152 and packing means 153 with flow conductor 21 prevents rotation of well packer 23 relative thereto. From studying the previous description and related drawings, it is readily apparent that the present invention allows a wide variety of subsurface safety valves to be used with the submersible pump installation. The minimum dimensional requirement for selecting an alternative safety valve is that when the valve is attached to threads 94 of locking mandrel 90, sealing means must be positioned on opposite sides of port means 89 to direct control fluid flow to the safety valve's hydraulically actuated means. The minimum operational requirement for alternative safety valves is that relatively low discharge pressure from pump P must be able to open the safety valve. INSTALLATION AND OPERATING SEQUENCE Safety valve S is releasably installed within landing nipple 40 below submersible pump P. Safety valve S can be opened and closed to control the flow of well fluids from the producing formation to the well surface. Pump P and its associated components are not directly attached to safety valve S. Therefore, pump P can be removed from its downhole location for maintenance and/or repair while safety valve S in cooperation with packer 23 blocks undesired formation fluid flow through flow conductor 21 to the well surface. When the complete system is in operation, formation fluids will flow into casing 21 below packer 23 through perforations (not shown). Packer 23 directs the formation fluid flow via packer bore 24 into the lower end of landing nipple 40. Safety valve S in its second or open position allows the formation fluids to continue flowing upwardly through bore 43 of travel joint 50, accumulator means 30 and inlet 32 into pump P. Formation fluids are then pumped to the well surface from discharge ports 22 via casing 21 above well packer 23. Well packer 23 is installed within flow conductor or casing 21 at the desired downhole location using conventional well completion techniques. Landing nipple 40 is releasably secured to upper portion 156 of well packer 23 by collet assembly 45. Safety valve S is next lowered through flow conductor 21 with equalizing assembly 93 open until locking mandrel 90 is engaged with locking grooves 84 of landing nipple 40. Equalizing assembly 93 is then shut. Springs 112 and 120 cooperate to hold safety valve S in its first position blocking fluid flow to the well surface. Spring 112 holds poppet valve means 106 shut, and spring 120 holds ball valve means 117 shut. Pump P and the components attached thereto can then be lowered through flow conductor 21 until seating mandrel 33 rests on shoulder 44 of landing nipple 40 above safety valve S. When pump P is turned on, the liquid contained in accumulator means 30 is discharged from pump P to variable volume chamber 104 via port means 89 to open safety valve S. Poppet valve means 106 will open first to increase the supply of liquids to pump inlet 32. Continued operation of pump P will cause further movement of inner cylinder 105 until ball valve means 117 is opened. At this time, well fluids will flow into bore 100 via ball 119 and openings 110 and 111. From bore 100 well fluids will flow through bore 43 into pump inlet 32 and be discharged from outlets 22 to the well surface. The discharge pressure of pump P is applied to variable volume chamber 104 to hold safety valve S open as long as pump P is operating. When pump P is turned off, springs 112 and 120 cooperate to return safety valve S to its first or closed position. Pump P and the components attached thereto may be safely removed from casing 21 when safety valve S is in its first position. If necessary for well maintenance or workover, safety valve S and landing nipple 40 can be removed from flow conductor 21 by conventional wireline techniques. Thus, the present invention allows for easy repair or replacement of submersible pump P, components attached thereto and the safety system. The previous description and drawings illustrate only one embodiment of the present invention. Alternative embodiments will be readily apparent to those skilled in the art without departing from the scope of the invention which is defined by the claims.

A landing nipple and safety system for installation in wells having a submersible pump for pumping well fluids to the surface plus a subsurface safety valve for maintaining the well under control during installation and removal of the pump from the well. The subsurface safety valve is hydraulically actuated by the discharge pressure of the pump. The landing nipple on which the pump is mounted and in which the safety valve is installed can be retrieved from the flow conductor by conventional wireline techniques.

You are an expert at summarizing long articles. Proceed to summarize the following text: PRIORITY CLAIM The present application claims priority to European Patent Application 05107316.1 filed Aug. 9, 2005. FIELD OF THE INVENTION The present invention relates to a system for injecting an injection fluid into an earth formation via a wellbore formed in the earth formation and for producing hydrocarbon fluid from the earth formation via the wellbore. The injection fluid can be, for example, steam that is injected into the formation at high temperature and pressure to lower the viscosity of heavy oil present in the formation so as to enhance the flow of the oil through the pores of the formation during the production phase. In one such application, steam is injected through one or more injector wells drilled in the vicinity of one or more production wells, and oil is produced from the production wells. BACKGROUND OF THE INVENTION Instead of using separate wells for steam injection and oil production, a single well can be used for the injection of steam and the production of oil. In such operation the injection of steam and the production of oil occur in a cyclic mode generally referred to as Cyclic Steam Simulation (CSS) process. In the CSS process, the well is shut in and steam is injected through the well into the oil-bearing formation to lower the viscosity of the oil. During a next stage, oil is produced from the formation through the same well. In order that the steam is injected substantially uniformly along the portion of the well penetrating the reservoir zone, i.e. without a concentration of injected steam at one location at the cost of another location, the steam is generally pumped through spaced outlet ports having a relatively small diameter, generally referred to as Limited Entry Perforations (LEP). This is done to ensure that the steam exits the outlet ports at a velocity approaching sonic velocity and is therefore choked or throttled. The size of the outlet ports typically is of the order of 0.5-1.0 inch. U.S. Pat. No. 6,158,510 suggests a wellbore liner for CSS including a base pipe provided with a plurality of LEP ports spaced in longitudinal direction and circumferential direction of the liner. The liner is provided with several sandscreens spaced along the liner, each sandscreen extending around the base pipe at short radial distance therefrom. During each steam injection cycle, the well is shut in and steam is injected into the rock formation via the LEP ports. The steam flows through the LEP ports at sub-critical velocity so that the flow rate of steam in the LEP ports is independent from pressure variations downstream the ports, thus ensuring a uniform outflow of steam along the liner. After a period of steam injection, a production cycle is started whereby oil from the surrounding rock formation flows via the LEP ports into the liner and from there to a production facility at surface. It is a drawback of the known system that, during the production cycle, the volumetric flow rate of oil through the LEP ports is relatively low. The amount of oil produced from the well in a given period of time is therefore also low. U.S. Pat. No. 5,865,249. discloses a system configured to flush debris from the bottom of a wellbore by injecting water via a water injection conduit into the plugged zone and inducing the debris to flow up through the wellbore through the production conduit. SUMMARY OF THE INVENTION In accordance with the invention there is provided a system for injecting an injection fluid into an earth formation via a wellbore formed in the earth formation and for producing hydrocarbon fluid from the earth formation via the wellbore, the system comprising an injection conduit extending into the wellbore and being in fluid communication with a plurality of outlet ports for injection fluid, the system further comprising a production conduit extending into the wellbore and being in fluid communication with at least one inlet section for hydrocarbon fluid, wherein the injection conduit is arranged to prevent fluid communication between the injection conduit and each said inlet section, characterised in that the injection fluid is a heated fluid which is injected into the formation in order to reduce the viscosity of hydrocarbon fluids within the formation. By virtue of the feature that the injection conduit is arranged to prevent fluid communication between the injection conduit and each inlet section, it is achieved that the injection fluid can be injected through the LEP ports of small size, whereas oil can be produced through each inlet section of a much larger size. Suitably the injection conduit and the production conduit are separate conduits. Furthermore, it is preferred that the outlet ports are comprised in a plurality of series of outlet ports, wherein the system comprises a plurality of said inlet sections, and wherein said inlet sections and said series of outlet ports are arranged in alternating order in longitudinal direction of the wellbore. In this manner it is achieved that injection fluid is injected at locations along the liner inbetween the inlet sections thereby ensuring substantially uniform heating of the rock formation along the length of the liner. The invention will be described hereinafter in more detail by way of example, with reference to the accompanying drawings in which: BRIEF DESCRIPTION OF THE INVENTION FIG. 1 schematically shows a wellbore for the production of hydrocarbon fluid from an earth formation, provided with an embodiment of the system of the invention; FIG. 2 schematically shows a portion of a liner used in the system of FIG. 1 ; FIG. 3 schematically shows side view 3 - 3 of FIG. 2 ; and FIG. 4 schematically shows an upper portion of the liner used in the system of FIG. 1 . DETAILED DESCRIPTION OF THE INVENTION In the Figures like reference numerals relate to like components. Referring to FIG. 1 there is shown a wellbore 1 for the production of hydrocarbon oil and gas from an earth formation 2 . The wellbore 1 has an upper section 3 extending substantially vertical and a lower section 4 extending substantially horizontal. A wellhead 5 is arranged at the earth surface 5 a above the well 1 . The lower wellbore section 4 penetrates a reservoir zone 2 A of the earth formation 2 . A conventional casing 6 extends from surface into the vertical wellbore section 3 , and a production liner 8 extends from the lower end of the casing 6 into the horizontal wellbore section 4 . A packer 10 seals the outer surface of the liner 8 relative to the inner surface of the casing 6 . The liner 8 comprises a plurality of inlet sections in the form of tubular sandscreens 12 for reducing inflow of solid particles, and a plurality of tubular bodies 14 . As is shown in FIG. 1 , the screens 12 and the tubular bodies are arranged in alternating order in the horizontal wellbore section 4 . Each tubular body 14 is provided with a series of outlet ports 16 of relatively small diameter for injection of fluid into the reservoir zone 2 A of the earth formation 2 . As discussed hereinbefore, outlet ports of this type are referred to as Limited Entry Perforations (LEP) which limit the flow rate of injection fluid into a zone at a given injection pressure by virtue of the fact that the velocity of injection fluid exiting the outlet ports approaches the sonic velocity. The outlet ports 16 of a series are regularly spaced in circumferential direction of the tubular body 14 . The sandscreens 12 are of conventional type, including a perforated base pipe (not shown) and a tubular filter layer 13 extending around the perforated base pipe. The base pipe of each sandscreen 12 is connected to the respective tubular bodies 14 adjacent the base pipe by conventional screw connectors (not shown) or by any other suitable means, for example by welding. The wellbore 1 is further provided with a production conduit 18 for the transportation of produced hydrocarbon fluid through the wellbore 1 to surface, the conduit 18 having an inlet opening 19 near the upper end of the liner 8 , and an injection conduit in the form of a coiled tubing 20 for the injection of injection fluid into the reservoir zone 2 A of the earth formation 2 . Reference is further made to FIG. 2 in which one of the tubular bodies 14 is shown in longitudinal section. The tubular body 14 is provided with a central through-passage 22 extending in longitudinal direction, the through-passage 22 having a mid-portion of enlarged diameter forming a chamber 24 that is in fluid communication with the exterior of the tubular body 14 by means of the outlet ports 16 . The coiled tubing 20 extends through the through-passage 22 and has a slightly smaller outer diameter than the diameter of the through-passage 22 so as to allow the coiled tubing to slide through the through-passage 22 . The coiled tubing 20 has one or more outlet openings 26 debouching in the chamber 24 of the tubular body 14 . Annular seals 28 , 30 are provided at either side of the chamber 24 to seal the coiled tubing 20 relative to the passage 22 . Thus, the coiled tubing 20 passes through the liner 8 , with the openings 26 being located in the respective chambers 24 of the tubular bodies 14 . A plug (not shown) closes the lower end of the coiled tubing 20 at a location below the chamber 24 of the lowermost tubular body 14 . Referring further to FIG. 3 there is shown a side view of the tubular body 14 that is provided with a series of through-bores in the form of production ports 32 fluidly connecting the respective ends 34 , 36 ( FIG. 2 ) of the tubular body 14 . As shown, the production ports 32 are regularly spaced in circumferential direction of the tubular body 14 . The outlet ports 16 for injection fluid (indicated in phantom in FIG. 3 ) do not intersect the production ports 32 . In FIG. 4 is shown the upper end of the liner 8 extending into the casing 6 , with the packer 10 sealing the upper end of the liner 8 relative to the casing 6 . As shown, the inlet opening 19 of the production conduit 18 is located in the lower end part of the casing 6 . During a first stage of normal operation, the well 1 is shut in and an injection fluid, such as high temperature steam, is pumped at surface into the coiled tubing 20 by means of a suitable injection facility (not shown). The steam flows downwardly through the coiled tubing 20 , and via the outlet openings 26 into respective chambers 24 of the tubular bodies 14 . Leakage of steam along the through-passages 22 of the tubular bodies 14 is prevented by the annular seals 28 . From the chambers 24 , the steam flows through the outlet ports 16 and into the wellbore 1 . From there, the steam flows into the reservoir zone 2 A of the surrounding earth formation 2 . As discussed before, the outlet ports 16 are Limited Entry Perforations (LEP) which have a relatively small diameter so as to limit the flow rate of steam through the outlet ports 16 . The pressure at which the steam is injected into the coiled tubing 20 is sufficiently high to ensure that the flow rate of steam in the outlet ports 16 approaches sonic velocity, so that the flow rates are independent of pressure differences downstream the outlet ports 16 . It is thus achieved that the steam is substantially uniformly distributed over the various outlet ports 16 , and that increased flow through one port 16 at the cost of another port 16 is prevented. The steam heats the reservoir zone 2 A whereby the viscosity of the oil in the reservoir zone 2 A is lowered. During a second stage of normal operation, after a period of continued steam injection into the reservoir zone 2 a , the injection of steam is stopped. The coiled tubing 20 is then retrieved from the wellbore 1 or, alternatively, can remain in the wellbore 1 for the next cycle of steam injection. The well 1 is then opened to start oil production from the reservoir zone 2 A, whereby the oil flows into the sandscreens 12 and, from there, via the production ports 32 of the respective tubular bodies 14 towards the production conduit 18 . The oil enters the production conduit 18 at its inlet opening 19 , and flows to surface to a suitable production facility (not shown). It will be understood that injected steam initially flows back into the well 1 before oil starts flowing into the well 1 . Thus, by the separate arrangement of production conduit 18 and the injection conduit 20 it is achieved that the production of oil is not limited to inflow of oil through the small outlet ports 16 for injection fluid. Instead, oil is produced at flow rates comparable to oil production from wells that do not require injection of steam into the formation. After a period of continued oil production from the well 1 , a next cycle of steam injection is started. The coiled tubing 20 is to be re-installed in the well 1 in case it was retrieved from the well 1 after the previous steam injection cycle. The aforementioned first and second stages of operation are then repeated in cyclic order.

A system is provided for injecting an injection fluid into an earth formation via a wellbore formed in the earth formation and for producing hydrocarbon fluid from the earth formation via the wellbore. The system comprises an injection conduit extending into the wellbore and being in fluid communication with a plurality of outlet ports for injection fluid, and a production conduit extending into the wellbore and being in fluid communication with at least one inlet section for hydrocarbon fluid. The injection conduit is arranged to prevent fluid communication between the injection conduit and each said inlet section.

You are an expert at summarizing long articles. Proceed to summarize the following text: TECHNICAL FIELD This invention relates generally to fenestration and more particularly to compound windows and doors formed from two or more individual window or door units joined together or mulled to create a larger multi-unit fenestration assembly. BACKGROUND Compound fenestration units, commonly referred to as mulled fenestration units, are formed by joining two or more individual window or door units, which will hereinafter be referred to as component units, so as to form a combination of windows, or windows and doors, that can be handled and installed as a single unit, and which give the appearance of being a single unit. A simple system for joining the component units involves the placing of spacer boards between the units to be joined and installing screws or other fasteners through the frames of the component units, into the spacer boards, to join the units. Other systems for joining the units involve the use of interlocking brackets or other like devices that can be separately installed on the facing surfaces of the frames to be joined and then coupled together to form the compound unit. An important aspect of compound fenestration units is that a great variety of different compound fenestration units can be formed from a relatively limited set of component units. Assembly of component window or door units into compound fenestration units involves not only mechanical coupling of the component window units, but also sealing of the joints between the component units against rain, wind, and other intrusions. Additionally, it is preferred that any sealing system accommodate a variety of gap arrangements and provide a suitable appearance to the compound unit. Silicone RTV, for example, can provide effective sealing for virtually any gap arrangement, either by itself or in combination with weather stripping or other covering or trim pieces, but the appearance of the sealed unit may be less than desirable, and may not provide the desired appearance of a single integrated unit. Additionally, the skill and equipment needed for the proper application of silicone or other like sealants may not always be readily available in all manufacturing settings. More visually pleasing sealing methods, such as preformed gaskets or trim materials can suffer, on the other hand, from a lack of adaptability to different combinations of component window units. There thus is a continuing need for a method and apparatus for joining together individual window units or door units to form multi-unit fenestration assemblies that addresses the problems and shortcomings of the prior art. It is to the provision of such that the present invention is primarily directed. SUMMARY OF THE INVENTION A system for creating compound fenestration units having sealed interfaces between the component units is disclosed. Briefly described, the system includes coupling structures for quickly and conveniently connecting component units to form robust compound units, as well as a sealing system for sealing the interfaces between the component units. The coupling structures provide coupling members that are attached to component units and then coupled to one another by interlocking channels and tabs. In one embodiment, the coupling members extend along the edge of the component units to be joined, and may extend beyond the edges, from one component unit to another, so as to reinforce the compound unit. In another embodiment, the coupling members are relatively discrete components, several of which are attached at various points along the edges of the various component units. The coupling structures also control the spacings between the component units so as to cooperate with a system of sealing components provided for sealing the gaps between the component units. The sealing system is of a dual seal type, with exterior, or shielding seals, and interior, or pressure seals, wherein the interseal cavities between the shielding seals and the pressure seals are provided with drain passages to convey water to a harmless location, such as the exterior of the structure in which the unit is installed. The seals are supported by a low shrink, dimensionally stable material, such as aluminum, so as to form a lineal sealing stock that is compressible in a transverse direction to allow insertion into gaps between component units, yet sufficiently rigid to urge the seals into sealing contact with the surfaces against which they are to seal. As used herein, the term lineal will refer to an elongated structure having a constant cross section over its length. Examples of lineals include stock materials of indefinite length, and components of a specific length that may, in addition, have specific end configurations to enable them to fit with other surfaces. The system of the present invention includes lineal sealing stock material for vertical gaps between component units and lineal sealing stock having an additional drip edge for sealing horizontal gaps between component units. The system further comprises end sealing components that cooperate with the pressure seals as well as with the shielding seals to provide pressure sealing where needed and ventilation and drainage where needed. The invention will be better appreciated upon review of the detailed description set forth below in conjunction with the accompanying drawing figures, which are briefly described as follows. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an elevation view of a compound fenestration unit. FIG. 2 is an embodiment of a system for joining component units to form a compound fenestration unit. FIG. 3 is a compound fenestration unit joined in the manner portrayed in FIG. 2 . FIG. 4 is a cross sectional view of the joint connecting the component units portrayed in FIGS. 1-3 . FIG. 5 is a cross sectional view of an embodiment of a channel and tab joining structure, prior to joining. FIG. 6 is the channel and tab joining structure portrayed in FIG. 5 in an intermediate position in preparation for joining. FIG. 7 is the channel and tab joining structure portrayed in FIGS. 5-6 after joining but prior to installation of wedging screws. FIG. 8 is the channel and tab joining structure portrayed in FIGS. 5-7 after installation of wedging screws. FIG. 9 is a cross sectional view of a first coupling member for an alternative embodiment of a coupling system for connecting component units. FIG. 10 is an elevation view of the first coupling member portrayed in FIG. 9 . FIG. 11 is a cross sectional view of a second coupling member for an alternative embodiment of a coupling system for connecting component units. FIG. 12 is an elevation view of the second coupling member portrayed in FIG. 11 . FIG. 13 shows the first and second coupling members portrayed in FIGS. 9-12 positioned for sliding into the coupling position. FIG. 14 is an elevation view of the assembled joining system portrayed in FIGS. 9-13 . FIG. 15 a is a cross sectional view of the joint formed by the coupling system portrayed in FIGS. 9-14 . FIG. 15 b is an elevation view of a compound fenestration unit joined by the joining system portrayed in FIGS. 9-15 a. FIG. 16 is a cross sectional view of a backbone portion of an embodiment of a vertical sealing strip according to the present invention. FIG. 17 is a cross sectional view of an embodiment of a vertical sealing strip. FIG. 18 is a cross sectional view of a joint in a compound fenestration unit sealed by the sealing strip portrayed in FIG. 17 . FIG. 19 is a cross sectional view of a backbone portion of an embodiment of a horizontal sealing strip. FIG. 20 is cross sectional view of an embodiment of a horizontal sealing strip. FIG. 21 is a cross sectional view of a horizontal joint sealed with the sealing strip portrayed in FIG. 20 . FIG. 22 is an embodiment of a sealing component for sealing ends of gaps between component units, and for sealing gaps between nailing flanges in compound fenestration units. FIG. 23 is a compound fenestration unit utilizing the sealing component portrayed in FIG. 22 . FIG. 24 is an end cover for a vertical sealing strip. FIG. 25 a is a compound fenestration unit utilizing the end cover portrayed in FIG. 24 to seal the top end of a vertical sealing strip. FIG. 25 b is a compound fenestration unit utilizing the end cover portrayed in FIG. 24 for sealing the bottom end of a vertical sealing strip. FIG. 26 is a view of a portion of a compound fenestration unit comprising a gusset plate. FIG. 27 a is an embodiment of a junction seal for sealing junctions in gaps in a compound fenestration unit. FIG. 27 b is a cross sectional view of the junction seal portrayed in FIG. 27 a. FIG. 28 is a cutaway view of the junction seal portrayed in FIGS. 27 a - 27 b , installed in a compound fenestration unit. FIG. 29 is a partial view of a compound fenestration unit including junction seals and a horizontal sealing strip. FIG. 30 is an exploded view of an embodiment of an end sealing system for a horizontal sealing strip. FIG. 31 is a partial front view of the end sealing system portrayed in FIG. 30 , after installation of the seals. FIG. 32 is a cross sectional view of the end sealing system portrayed in FIG. 31 . FIG. 33 is a cross sectional view of the top portion of a fenestration unit, including an embodiment of a drip edge. FIG. 34 is a cross sectional view of the drip edge portrayed in FIG. 33 prior to installation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 portrays a compound fenestration unit 10 made up of component units 2 , 4 , 6 , and 8 , joined at their edges in a way that provides a single integrated unit. As used herein, the edge of a fenestration unit will refer to the surfaces that face one another when component units are joined into compound units. The plane of a fenestration unit will refer to the plane of the pane or other glazing unit. The interfaces between the units include horizontal gap 5 and vertical gap 7 , which cross at gap junction 9 , wherein each of gaps 5 and 7 have a predetermined width. Each component unit is provided with nailing flanges such as 13 , 14 , 16 , and 18 . Nailing flanges on the component units may be integral with each component unit, so as to completely surround the unit, in which case the portions of the nailing flanges on mating sides of the units to be joined are removed prior to assembly of the compound unit, leaving the peripheral portions of the nailing flanges for the compound unit. Alternatively, nailing flanges may be provided as separate parts, in which case they may be cut to length from stock material and installed on the outer periphery of the compound unit after assembly of the unit. Joining of the component units can be accomplished in a variety of ways. In the example shown in FIG. 2 , sashes, jamb liners, and other window component unit parts have been removed, to allow access to frames 26 and 28 , so that they can be attached to spacer board 24 by screws 23 . As shown in FIG. 3 , the thickness of board 24 determines the spacing between the units, in particular the spacing between sealing faces 27 and 29 , so as to define gap 32 . Referring to FIG. 4 , sealing faces 27 and 29 are typically formed by exterior trim cladding layers 43 and 45 , which can be made from, for example, polymeric materials such as PVC, or from aluminum. The steps of removing sashes and other parts from component window units prior to assembly into compound units, and then later replacing them, can be inconvenient and time-consuming. This step can be eliminated by the use of coupling systems that comprise a first coupling member that attaches, by external attachment means, to a first component unit, and a second coupling member that attaches, by external attachment means, to a second component unit, without the need to remove internal parts of the component units. The first and second coupling members are then interengaged with one another, thereby coupling the two component units together. The interengagement can utilize, for example, channels and tabs, wherein the tabs of one coupling member are received by the channels of the other coupling member and are locked in place by a clamping or wedging means. More particularly, a first coupling member may comprise a channel opening in a direction perpendicular to the plane of the unit, toward, for example, the exterior side of the unit, and the second coupling member may comprise a tab located in such a way as to be received by the channel in the first coupling member. It is useful for the coupling structures carrying the channels and tabs to be continuous lineal members that extend the full length of the mull. In some cases, this will mean that the coupling members will extend beyond a first unit to a second unit, in which case the coupling member will act as a reinforcement for the overall stiffness of the compound unit. The connection between the two coupling members can be made more rigid by adding an additional channel and tab coupling combination in a location at a suitable distance from the first channel and tab combination. The channel and tab couplings can be locked in place by addition of a wedging device to urge the tab against one wall of the channel. In one embodiment, a wedging screw has been found to be a useful device for locking the coupling members to one another. The wedging screw can be inserted through a hole in the bottom of the channel, parallel to the tab, to wedge itself between the tab and the wall of the channel so as to urge the tab against the wall. The screw can be a thread forming screw to enable it to secure itself in place by partially threading the channel wall or the side of the tab, or both. An embodiment of tab and channel couplings is shown in FIG. 5 . Referring to FIG. 5 , an embodiment of a channel and tab joining structure with a wedging screw is portrayed. The joining structure is made up of first mull coupling member 52 , attached to first component unit 501 , and second, cooperating, mull coupling member 56 , attached to a second component unit 502 . First coupling member 52 comprises tab 53 and channel 54 , joined by base plate 55 . Second mull coupling member 56 comprises channel 58 and tab 57 , joined by base plate 59 . Positioning of coupling member 52 relative to component unit 501 is determined by alignment channel 520 in unit 501 , which receives alignment and load transfer tabs 521 and 522 of first mull coupling 52 . In like manner, alignment channel 560 of unit 502 receives alignment and load transfer tabs 561 and 562 of second mull coupling member 56 . Tabs 521 , 522 , 561 , and 562 serve not only as locators, but also serve to transfer mechanical loading from coupling members 52 and 56 to component units 501 and 502 , respectively, thereby reducing the dependence on screws 523 for coupling of the component units. It will be appreciated that although alignment channels 520 and 560 provide the tab receiving features for the present embodiment, other tab receiving features, such as narrow kerfs, could also be used. Coupling members 52 and 56 can be produced by stamping and bending or roll forming of sheet metal stock, as would be apparent to one skilled in the art. Coupling members 52 and 56 are attached to component units 501 and 502 respectively by screws 523 , or by other suitable fasteners, as would be apparent to one skilled in the art. Referring again to FIG. 5 , the component units can be conveniently joined by first placing them on flat surface 50 and lifting unit 502 a distance d. The units are then brought together so that tab 53 of first mull coupling member 52 approaches base plate 59 of second mull coupling member 56 and tab 57 of second mull coupling member 56 approaches base plate 55 of first mull coupling member 52 , as shown in FIG. 6 . Referring to FIG. 7 , component unit 502 is then lowered, engaging tab 53 with channel 58 and simultaneously engaging tab 57 with channel 54 . The coupling formed by the combination of coupling members 52 and 56 is then locked by a series of wedging screws 83 , shown in FIG. 8 . Holes for receiving screws 83 can be predrilled or prepunched prior to assembly. Fixturing may be useful during the installation of screws 83 to prevent movement of coupling member 56 relative to coupling 52 during installation of screws 83 . It may also be useful to attach gusset plates or other reinforcing members to hold the components in more firmly fixed positions relative to one another both during and after assembly. After the component units have been joined, a gap 86 is defined by first sealing face 82 and second sealing face 84 . Additionally, gap 86 may contain first anchoring kerf 503 and second anchoring kerf 504 for receiving anchoring portions of a mull sealing member. Mull coupling members 52 and 56 may be provided as lineal members that extend along the full edges of the component units, and may also extend beyond a single component unit to adjacent component units. They may extend the full height or width of the compound unit, so as to act as a reinforcing structure for the compound unit. More particularly, in the compound unit portrayed in FIG. 1 , coupling members can extend from the bottom of bottom units 6 and 8 to the top of top units 2 and 4 , thereby providing additional reinforcement to the compound unit. Alternatively, a horizontal coupling member could extend the full length of horizontal gap 5 , from the left sides of units 2 and 6 to the right sides of units 4 and 8 , so as to bridge the component units in the horizontal direction. Referring to FIGS. 9-15 , an alternative embodiment of a coupling system for connecting component units is portrayed. In this embodiment, the coupling members are relatively short discrete components placed at suitable intervals along the edges of component window units to be joined, rather than being continuous coupling members, as disclosed in the previous embodiment. In this embodiment, first coupling member 900 comprises a base plate 902 , as portrayed in FIG. 9 , from which protrude alignment and load transfer tabs 903 and 905 in a first direction, and from which further protrude channel base portions 906 and 908 , at edges 915 and 917 , respectively, in a second direction. Lip portions 907 and 909 are attached to channel base portions 906 and 908 to form first channel 912 and second channel 914 respectively. While the various parts of side mull coupling member 900 are described as separate entities, it will be apparent to one skilled in the art that coupling member 900 can be produced as a single part, by, for example, stamping and bending of sheet metal. The formation of alignment and load transfer tabs 903 and 905 can be aided by first forming aperture 923 , shown in FIG. 10 , and then bending suitably punched tabs to form alignment and load transfer tabs 903 and 905 . Referring again to FIG. 10 , a side elevational view of first mull coupling member 900 shows a typical length to height aspect ratio of first mull coupling member 900 , as well as screw holes 1023 for attachment to component unit frames. Second side mull coupling member 1100 , portrayed in FIGS. 11-12 , comprises base plate portion 1102 , from which protrude alignment and load transfer tabs 1103 and 1105 in a first direction, and from which protrude spacer portions 1107 and 1109 in a second direction. Referring to FIG. 12 , guide tabs 1110 , 1112 , 1114 , and 1116 are attached to spacer portions 1107 and 1109 , to act as insertion guides during assembly of compound units. Referring again to FIG. 12 , a side elevational view of second mull coupling member 1100 shows a typical length to height aspect ratio of second mull coupling member 1100 , as well as screw holes 1223 for attachment to component unit frames. Referring to FIGS. 13 and 14 , first coupling tab 1107 and second coupling tab 1109 of second mull coupling member 1100 slide into first channel 912 and second channel 914 , respectively, of first mull coupling member 900 , to form complete coupling unit 1400 , as shown in FIG. 14 . FIG. 15 a shows a cross sectional view of a completed coupling of two component units, wherein first mull coupling member 900 is attached to a first window frame portion 1502 , and second mull coupling member 1100 is attached to a second frame portion 1504 , with each coupling being located relative to its respective component unit by alignment and load transfer tabs 903 and 905 of first coupling member 900 that fit into channel 1503 of first frame portion 1502 and alignment and load transfer tabs 1103 and 1105 that fit into channel 1505 of second frame portion 1504 . Referring to FIG. 15 b , gap width x can be controlled more precisely if spacer shims 1541 and 1542 are placed between coupling unit 1400 along gap 1507 between frame portions 1502 and 1504 . It is preferred that the thickness of the shims allow a snug to slightly compressed fit between frame portions 1502 and 1504 . It will also be apparent that the width of the shims should be chosen so as not to interfere with other components of the compound unit, such as mull sealing strips. Since the spacer shims are only used to maintain spacing x by supporting a relatively small compressive load, and do not serve a coupling function, the choice of suitable materials is relatively wide. Particularly useful materials for the spacer shims are rigid polymeric foams, such as polystyrene or polyurethane foam. Polymeric foams have the additional advantage of being good heat insulators. While the coupling systems disclosed hereinabove enable component units to be mechanically joined into compound glazing units, there is also a need to provide sealing of the joints between the component units against wind, rain, and other intrusions. For this purpose, a system of sealing strips and end seals is provided. In the embodiment shown in FIGS. 16-18 , a sealing strip particularly useful for sealing vertical gaps comprises a lineal backbone 1600 , having the cross section shown in FIG. 16 . Support 1600 comprises base portion 1601 having longitudinal edges 1610 and 1620 , to which are attached first leg portion 1602 and second leg portion 1604 . Hook portions 1605 and 1606 may further be attached to distal edges 1608 and 1609 of leg portions 1602 and 1604 , respectively. Support 1600 is compressible in transverse direction 1621 , so that legs 1602 and 1604 can be readily moved toward one another during, for example, installation of the sealing strip. While portions 1601 , 1602 , 1604 , 1605 , and 1606 have been described as separate entities, in practice they will typically be made as a single part, by, for example, forming from a sheet metal strip. Sealing at the top and bottom of a mull strip typically depends on the ends of the strip fitting snugly against end sealing components. For this reason, any significant shrinkage in the sealing strip adds to the risk that an end seal may fail, and leakage may occur. It is therefore preferred that support 1600 be made of a low shrink material, such as aluminum, in particular an aluminum alloy such as 5052 alloy, which is formulated for reduced corrosion. A convenient method of making the support portion is to form a strip of aluminum sheet by bending or roll forming. It is also useful for support member 1600 to be precoated or primed with an adhesion promoting, anti-corrosive, material, such as a chromate pigment in a polymeric binder. Such coatings are commercially available, and their selection and use would be apparent to one of ordinary skill in the art. Polyurethanes are particularly useful as binders for the coating. It will also be recognized that other backbone materials may provide sufficiently low shrink. For example, pultruded or otherwise reinforced polymeric materials may be suitable in some applications. Also, thermosetting polymeric materials may provide useful reductions in shrink, compared to thermoplastic materials. As will be recognized by one of ordinary skill in the art, the allowable shrink will depend on the ability of the end seals to accommodate dimensional changes without allowing leakage. Therefore, suitable shrinkage levels are those that are sufficiently low to be effective in maintaining the seals at the ends of the sealing strip, for the type of end seals being used, under conditions normally encountered by fenestration units. The present invention utilizes a dual sealing system, comprising exterior, or shielding seals, and interior, or pressure seals. The spaces between the exterior and interior seals will be referred to as interseal cavities. The interseal cavities have openings that allow drainage and ventilation, but which are shielded from direct wind. The interseal cavities serve as quiescent dry zones where, under conditions of wind and rain, only a limited amount of rain water enters, due to the shielding effects of the shielding seals and other shielding devices covering the openings. The pressure seals, on the other hand, are complete seals that seal the interseal cavities from the interior of the building. Since the interseal cavities contain little or no water, any leakage of the pressure seals is likely be leakage of air only, which would be unlikely to harm the interior of the building. Moreover, since the pressure seals are protected from weathering and mechanical damage by the shielding seals, the effectiveness of the pressure seals is likely to remain high over an extended period of time. Referring to FIG. 17 , a dual sealing system comprising several conformable seals attached to support member 1600 is portrayed. Shielding fins 1712 and 1722 are attached to support 1600 at longitudinal edges 1610 and 1620 . Pressure seals 1732 and 1734 are attached to legs 1602 and 1604 , respectively. It has been found useful to make seals 1732 and 1734 tubular in cross section and somewhat inclined toward the exterior side, for ease of installation of sealing strip 1700 , combined with effective sealing. Sealing strip 1700 further comprises cross member 1703 , which divides it into an exterior portion and an interior portion. The exterior portion of sealing strip 1700 , that is to say the portion facing the exterior of the structure in which the compound unit is installed, is the portion of the sealing strip between base portion 1601 and cross member 1703 , while the interior portion is the portion facing the interior of the structure, that is to say the portion between cross member 1703 up to and including hook portions 1605 and 1606 . Cross member 1703 , base portion 1601 , and the portions of legs 1602 and 1604 between cross member 1703 and base portion 1601 collectively define cavity 1707 , which is open at the bottom end to allow any water that may be present to be conveyed to a harmless exterior location. Centering and consistent compression of sealing strip 1700 in the gap to be sealed is aided by ribs 1742 and 1744 , as well as by ribs 1746 and 1748 . Referring to FIG. 18 , sealing strip 1700 is installed in gap 86 , with hooks 1605 and 1606 engaging kerfs 503 and 504 . Kerfs 503 and 504 provide stops for strip 1700 , and help to orient it relative to gap 86 . Kerfs 503 and 504 also provide additional assurance that strip 1700 will not be unintentionally removed from gap 86 . Shielding fins 1712 and 1722 fit against sealing faces 82 and 84 , respectively, to form a shielding seal. Inner seals 1732 and 1734 also fit against sealing faces 82 and 84 , respectively, to form a pressure seal, thereby forming interseal cavities 182 and 184 . Interseal cavities 182 and 184 , as well as cavity 1707 , are able to drain any water that may be present to a harmless location. They may also be ventilated at the top by shielded ventilated apertures. The seals formed by fins 1712 and 1722 , along with the various shielding components at the top and bottom ends, are often sufficient to prevent leakage. However, under some conditions, such as severe cases of wind and rain, some water may enter interseal cavities 182 and 184 . Since the air in cavities 182 and 184 can be expected to be relatively quiescent, however, any leaked water is likely to drop to the bottom of these cavities, where it can drain out through openings 2510 and 2520 , as shown in FIG. 25 b . Pressure seals 1732 and 1734 perform the primary sealing function, since the primary part of the pressure drop from exterior to interior occurs across these seals. Since there is expected to be relatively little airborne water in cavities 182 and 184 , however, any leakage past these seals is likely to be primarily leakage of air. Moreover, since seals 1732 and 1734 are protected from direct sunlight, as well as from mechanical damage, it is expected that these seals will maintain a high level of reliability. A useful method for producing sealing strip 1700 is to feed formed backbone 1600 through an extrusion die so as to extrude shielding fins 1712 and 1722 , along with pressure seals 1732 and 1734 , cross member 1703 , and centering ribs 1742 , 1744 , 1746 , and 1748 onto the support. Since shielding fins 1712 and 1722 present visible surfaces when installed, it is useful for them to have a color that is compatible with the units being sealed. Likewise, since base area 1601 between fins 1712 and 1722 is also visible, it is also useful to cover it with extruded material of a similarly suitable color. After extrusion of the polymeric material onto support 1600 , the resulting extruded stock material is cut to length. The length of vertical mull sealing strips is typically less than the height of the window by an amount sufficient to allow insertion of a compressed end seal at each end, while still maintaining compression of the end seal. While sealing strip 1700 has been found effective for sealing vertical gaps in compound fenestration units, an alternative sealing strip, comprising a low shrink backbone portion and conformable sealing portions, along with a drain ramp and drip edge, has been found especially effective for sealing horizontal gaps, while also helping to divert water away from areas of possible leakage. Referring to FIG. 19 , sealing strip backbone portion 1900 comprises first vertical wall 1901 , from which extend top leg portion 1902 and bottom leg portion 1904 in a first, interior, direction, and from which extends drain ramp 1922 in a second, exterior, direction. Additionally, top anchoring hook portion 1905 is attached to distal edge 1908 of top leg portion 1902 , and bottom anchoring hook portion 1906 is attached to distal edge 1909 of bottom leg portion 1904 . A second, lower, wall 1924 is attached to drain ramp 1922 at its distal edge 1920 . Wall 1924 terminates at drip edge 1926 . A series of drain holes 1930 and 1932 are also provided to enable diversion of leaked water to a harmless location such as the exterior side of the window unit. Referring to FIGS. 20 -21 , top shielding fin 2040 and bottom shielding fin 2030 provide shielding against wind and rain, while interior pressure seals 2010 and 2020 provide the primary sealing against leakage due to pressure differentials. Referring to FIG. 21 , interseal cavities 282 and 284 provide dry quiescent zones that enable collection of any water that may have leaked past shielding fin 2040 . Drain holes 1930 and 1932 allow water to drain to a harmless location, such as the exterior of the structure in which the unit is installed. Drain ramp portion 2050 and vertical wall portion 2052 serve to divert rain or other water to drip edge 2053 , where it can fall to the ground or to other harmless locations. Since surfaces 2050 , 2051 , and 2052 are visible surfaces, it is useful to also coat these surfaces with a suitably colored polymeric material. As shown in FIG. 21 , horizontal sealing strip 2000 is used to seal horizontal gap 2115 between upper component unit 2110 and lower component unit 2120 . Kerfs 2112 and 2122 are provided for receiving hooks 1905 and 1906 , so as to assure that sealing strip 2000 is inserted to the proper distance during installation and that it is secured in place after installation. While vertical sealing strips 1700 and horizontal sealing strips 2000 can be effective in sealing gaps, it will be recognized that ends of gaps and junctions of gaps will inevitably occur in compound fenestration units. Moreover, gaps in nailing flanges between component units also occur. Referring to FIG. 22 , a seal for sealing the ends of gaps, along with gaps in nailing flanges, is portrayed. Seal 2200 is made of a conformable foam material and comprises flange gap sealing portion 2210 and gap filler portion 2220 . Seal 2200 can be produced by any suitable means, such as cutting from a solid block of foam, or by adhering suitably dimensioned strips of foam together, as would be apparent to one skilled in the art. It has been found that seal 2200 is more effective in its sealing function if the surface skinning effect commonly encountered in molding of foams can be avoided, so that the porosity of the foam found in the interior of the part also extends to the surface. A useful polymeric material for the foam is EPDM polymer. In addition, it has been found that lubricating the surface of the foam seal with an inert lubricant such as talc prior to installation is useful in easing installation and enabling the foam to properly seat so as to form an acceptable seal. Referring to FIG. 23 , seal 2200 is shown installed at the top end of vertical sealing strip 1700 , where it cooperates with the top ends of the pressure seals of strip 1700 , and also fills the gap between nailing flanges 2312 and 2322 . An end cover, portrayed in FIG. 24 , is installed in cavity 1707 to compress gap filler portion 2220 against gap sealing strip 1700 to form a more secure seal and to cover cavity 1707 , while allowing ventilation of cavity 1707 . Referring again to FIGS. 23 and 24 , top end cover 2450 is comprised of cover portion 2449 and barbed retainer clip portion 2470 . Cover 2450 is installed by inserting clip portion 2470 into cavity 1707 and pressing down until stop rib 2458 engages surface portion 1750 of strip 1700 , and locator notch 2455 of rib 2457 engages surface portion 1759 of strip 1700 . As a result, end portion 2459 of cover 2450 compresses gap filler portion 2220 of foam seal 2200 against the ends of pressure seals 1732 and 1734 , thus completing the pressure seal at the top end, while still allowing ventilation of the interseal cavities and cavity 1707 , as shown in FIG. 25 a . Compression of filler portion 2220 is maintained by engagement of barbs 2471 with the interior surfaces of cavity 1707 of sealing strip 1700 . Referring again to FIG. 25 a , it will be noted that the width of cover 2450 is slightly less than the spacing between component units 2310 and 2320 , so as to leave gaps between sealing faces 2501 and 2502 and cover 2450 , which allow ventilation of cavity 1707 , and of interseal cavities 182 and 184 . Referring to FIG. 25 b , cover 2450 can also be used, along with foam seal 2200 , at the bottom end of vertical sealing strip 1700 . Since cover 2450 is slightly narrower than the gap between sealing faces 2501 and 2502 , drain openings 2510 and 2520 are created, which allow drainage of leaked water from cavity 1707 and interseal cavities 182 and 184 . Referring to FIG. 26 , the structural strength of the compound fenestration unit can be further enhanced by providing gusset plates such as plate 2600 . Plate 2600 can be made from stamped and bent sheet metal, such as steel. Tabs 2607 engage channels 2605 and 2606 in component units 2310 and 2320 , respectively, to position plate 2600 relative to component units 2310 and 2320 , as well as to position units 2310 and 2320 relative to one another. Additionally, tabs 2607 strengthen the mechanical coupling of plate 2600 to component units 2310 and 2320 . Backup tab 2620 reinforces the attachment of the compound unit to the building structure, and also sandwiches flange gap sealing portion 2210 so as to enhance sealing at the gap between nailing flanges 2312 and 2322 . It will be appreciated that when the compound fenestration unit is installed in a rough opening, screws inserted through holes 2315 serve to not only hold the compound unit in place, but also serve to compress portion 2210 of seal 220 for improved sealing reliability. Junctions of horizontal gaps and vertical gaps, such as junction 9 in FIG. 1 , also require sealing. An embodiment of a junction seal is portrayed in FIGS. 27 a and 27 b . Junction seal 2700 comprises a conformable sealing portion 2710 that is attached to support portion 2720 . A suitable conformable material is polymeric foam, made, for example, by foaming EPDM polymer. Support portion 2720 comprises backbone portion 2723 , which connects front trim portion 2724 with rear base portion 2722 , to which is attached anchoring tab 2725 . It has been found that the sealing effectiveness of conformable portion 2710 can be enhanced by certain shape features. In particular, edges 2712 and 2714 are made as thin as possible, to provide a smooth transition with the sealing face of the fenestration unit, thereby allowing other sealing surfaces, such as pressure seal 2020 of sealing strip 2000 and shielding seal 2030 to fit over them without voids in the sealing area. In addition, the trapezoidal shape of backbone portion 2723 allows conformable portion 2710 to conform to it and thus provide a relatively seamless, void free, transition between surface 2715 of conformable material 2710 and surface 2725 of backbone 2723 . It will be appreciated that cross sectional shapes other than trapezoidal for backbone 2723 may also be suitable, provided that they promote a smooth and void-free conformance of material 2710 to the backbone. Referring to FIG. 28 , the sealing of gaps at junctions is performed by first installing vertical sealing strips 2815 and 2816 . Top and bottom junction seals 2700 are then installed, as shown, with surface 2712 of conformable material 2710 pressing against the ends of vertical seals 2815 and 2816 , thereby completing the pressure seal. The thin edges of compliant sealing material 2710 form a low profile surface that merges with top surface 2807 of component unit 2806 and top surface 2809 of component unit 2808 to form a sufficiently smooth surface for bottom pressure seal 2020 , shown in FIG. 20 , of horizontal sealing strip 2000 to seal against it. Finally, referring to FIG. 29 , horizontal sealing strip 2000 is installed. Because junction seal 2700 is adapted to provide a smooth, void free surface, without sharp transitions, against which interior seals 2010 and 2020 of horizontal sealing strip 2000 can seal, the presence of junction seals 2700 does not significantly disrupt the sealing of strip 2000 against the component window units. Conformable material 2710 is compressed against vertical sealing strips 1700 by pressure seals 2010 and 2020 of horizontal sealing strip 2000 . The ends of horizontal sealing strip 2000 can be sealed by a sealing system of the type shown in FIG. 30 . Right hand end cap 3050 comprises cover portion 3049 and retainer clip portion 3070 . Cover portion 3049 further comprises notched rib 3057 , wherein notch 3055 fits over the end of wall 3059 and seats against it. Barbed leaf retainer clip 3070 comprises an upper leaf, visible, and a lower leaf, not visible, which fit into cavity 2007 , with barbs 3071 of the upper leaf and lower leaf engaging the upper and lower walls of cavity 2007 , respectively. End cap 3050 is further located relative to end 3051 of strip 2000 by stop rib 3058 , which rests against end 3051 . Surface profile 3054 is shaped to match the exterior profile of the window frame against which it fits, so as to provide a harmonious appearance. In like manner, surface profile 3052 is similar to combined portions 2050 and 2052 of strip 2000 , which it slightly overlaps, as shown by dashed lines 3053 in FIG. 30 . End seal portion 2220 of flange seal 2200 is interposed between end cap 3050 and end 3051 of strip 2000 so as to provide a pressure seal of cavity 2005 . Barbed retainer clip 3070 is useful in holding end cap 3050 tightly against seal 2220 so as to maintain a level of compression that is adequate for a pressure seal. As shown in FIGS. 31 and 32 , portion 2210 of flange seal 2200 fits behind nailing flanges 3103 and 3105 of component units 3102 and 3104 , with portion 2220 protruding through the gap between the window units and compressed against sealing strip 2000 by end cap 3050 . Since exterior cavity 2007 is exterior to the pressure seal, it is not necessary for it to be sealed to end cap 3050 , and it is useful for it not to be sealed, so as to provide ventilation to cavity 2007 . Fenestration units of the present invention can be further protected against intrusion of water by the addition of a top drip cap. Referring to FIGS. 33 , top rail portion 340 of a fenestration unit is shown installed in a rough opening having header 346 , to which is attached sheathing 348 . In this embodiment, top rail portion 340 comprises laminated wood core 342 and cladding 343 . Nailing flange 347 is an integral extension of cladding 343 . Cladding 343 is typically PVC, with an outer cap stock to impart weatherability and improved color, but may also be aluminum or other suitably durable and weatherable material. In a preferred embodiment, drip cap 330 comprises a mechanically and thermally stable core 332 , over which is applied one or more polymeric layers to form nose portion 334 , which is held in a spaced apart position from top rail 340 by spacer rib 335 , so as to move dripping water away from the fenestration unit. Core 332 is preferably a relatively rigid material having a low coefficient of thermal expansion, having a low long term shrinkage. A material that has been found suitable is aluminum, although other materials such as pultruded fiberglass reinforced polymeric materials may also be useful in some applications. An aluminum core may have an advantage in some instances in that it is relatively easy to produce from sheet stock. A preferred polymeric material for the coating layers is PVC, which may be covered with a capstock material such as pigmented PVC or acrylic polymer. Acrylic polymers may be preferable in some instances, depending on color requirements and weathering conditions, for example. Drip cap 330 further comprises flexible sealing flap portion 338 which folds upward and fits against nailing flange 347 . Referring to FIG. 34 , drip cap 330 is formed by extrusion of polymeric material over aluminum core 332 , with sealing flap extending in a substantially parallel direction with core 332 . Since flap portion 338 is flexible, it can be bent at any suitable point to conform to a variety of fenestration unit dimensions. Referring again to FIG. 34 , drip cap 330 can be produced as a stock material by extruding polymeric material over core 332 . It is preferred that the extruded polymeric material completely enclose core 332 , and that it impart a suitable color to the visible portion of the drip cap. The polymeric material also forms nose portion 334 , sealing flap 338 , and sonic welding energy directors 331 . When cladding 343 is a sonic weldable material such as PVC, drip cap 330 can be sonically welded to the cladding of the component units. When cladding 343 is not sonically weldable, a dual sided pressure sensitive tape foam tape, or other suitable adhesive means, can be used to attach drip cap 330 to cladding 343 . Because sealing flap 338 is flexible, it can be pulled away from nailing flange 347 during installation to allow fasteners 349 to be installed through nailing flange 347 into sheathing 348 and header 346 , so as to avoid puncturing it, thereby further reducing the risk of leakage.

A system is provided for coupling individual fenestration units together and sealing the gaps between them so as to form a sealed compound fenestration unit. The individual fenestration units include mating channels and tabs, or other connectors, that are attached to outside frame surfaces of the individual fenestration units. When the connectors are coupled together, they attach the frames of the individual fenestration units securely together in such a way that gaps are formed between the units along their joined frame surfaces. The gaps are sealed by resilient sealing strips that are configured to be inserted into the gaps, and that are formed with seals that bear against the walls of the gaps to form impervious moisture seals.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE This is a division of Ser. No. 042,431, filed May 25, 1979. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to tools for testing earth formations in boreholes and more particularly for making formation pressure measurements, acquiring information concerning formation permeability and productivity, and retrieving samples of formation fluids. 2. Description of the Prior Art Formation testing tools of the prior art of which I am aware have a number of deficiencies. It is important that such tools should have an effective failsafe arrangement to assure that the parts that are extended into contact with the formation when the tool is set can be retracted in the event of power failure, so that the tool can be removed from the borehole. The fail-safe arrangements of the prior art that I know of are actuated by a tensioning of the tool suspension cable to shear a pin or the like, and are subject to problems such as unintentional shearing of the pin, or inability to exert the requisite tensioning force due to cable key seating. Formation testing tools conventionally provide a pre-test chamber or chambers into which a small quantity of formation fluid (typically about 20 c.c.) can be drawn in order to make formation shut in pressure measurements and obtain indications of formation permeability and potential production. Once the pre-test procedure has been initiated, the entire pre-test chamber capacity must be filled with formation fluid before shut in pressure can be determined, which in the case of low permeability formations can consume considerable time. In addition, the lack of control between the initiation and completion of the pre-test procedure precludes desirable flexibility. Formation testing tools are typically quite long, and a considerable portion of their length is in the sample chamber portion, which is conventionally rigidly attached below the seal pad. While the tool is set, or when attempting to free the tool, this sample chamber portion can be jammed against the wall of the borehole and become differentially stuck. Formation testing tools of the prior art that I know of have had problems in maintaining isolation of the formation at the seal pad when testing in unconsolidated formations. Patents that exemplify prior art formation testing tools are U.S. Pat. Nos. 3,811,321, 3,813,936, 3,858,445, 3,859,850, 3,859,851, 3,864,970, 3,924,468, and 3,952,588. SUMMARY OF THE INVENTION A first objective of the present invention is to provide an improved failsafe arrangement to ensure the retracting of the seal pad means and backup pad means in the event of equipment malfunction. This is accomplished by providing electrically powered means controllable at aboveground equipment for generating and applying hydraulic setting pressure to extend and set the seal pad means and backup pad means; means for generating signals to be transmitted to above ground equipment, which signals are a measure of the hydraulic setting pressure, and power supply means for the signal generating means; and means operable in response to a failure of the power supply means to effect release of the hydraulic setting pressure and permit retraction of the seal pad means and backup pad means. In one aspect of the invention, the electrically powered means comprises a reversible electric motor coupled to driving means for moving a piston longitudinally of a cylinder which contains hydraulic fluid, and fluid passage means communicating between the cylinder and the seal pad means and backup pad means; and an electromagnetic clutch interposed in the driving means and operable in response to a failure of the power supply means to disengage the driving means. In a further aspect of the invention, the driving means comprises first and second gear reductions and a ball screw and ball nut, with the piston moveable with the ball nut; the electromagnetic clutch is interposed between the first and second gear reductions and has an energizing coil; the energizing coil being connected in series with the power supply means for the signal generating means; and spring bias means within the cylinder and exerting a force on the piston sufficient to overcome the frictional forces present in the ball screw and ball nut and second gear reduction when the electromagnetic clutch is de-energized, such that the piston is moved in the direction to increase the hydraulic fluid volume within the cylinder, thereby effecting release of the hydraulic setting pressure and permitting retraction of the seal pad means and backup pad means. Another objective of the invention is to provide improved apparatus for achieving formation "shut-in" pressure measurements and for obtaining indications of formation permeability and potential production, and for obtaining formation fluid samples. The improved apparatus provides a formation fluid mini-sample chamber having variable volume, and fluid passage means for communicating between the mini-sample chamber and the formation at the seal pad location; electrically powered means controllable at aboveground equipment to vary at the will of an operator the volume of the mini-sample chamber; means for generating signals to be transmitted to aboveground equipment, which signals are a measure of fluid pressure within the mini-sample chamber; and means for generating further signals to be transmitted to aboveground equipment, which further signals are a measure of the volume of the mini-sample chamber. In accordance with a further aspect of the invention, the electrically powered means comprises a reversible electric motor coupled through a gear reduction to a ball screw and ball nut; with the variable volume mini-sample chamber comprising a cylinder having a sealed upper end and being moveable with the ball nut; a floating piston is disposed within the cylinder and is pressure biased so as to normally close fluid passage means communicating between the formation at the seal pad location and a formation sample chamber; and means are provided to move the floating piston upwardly to open the last mentioned fluid passage means upon a predetermined upward movement of the cylinder. Another objective of the invention is to provide structure to alleviate the problem of sticking the tool in the borehole. The tool is made up of upper and lower elongated tool body sections and a pivot structure is provided connecting the lower end portion of the upper body section to the upper end portion of the lower body section for limited pivoting movement, with the axis of the pivoting movement being normal to the direction of movement of the seal pad means for extension and retraction. In another aspect of the invention, this pivot structure incorporates a seal valve for the formation sample chamber which is located in the lower tool body section. In accordance with another aspect of the invention, the seal valve comprises a body portion having a cylindrical exterior surface which acts as the pivot pin or journal for the pivot structure. In a further aspect of the invention, the valve body portion has cylindrical interior portions which carry respective first and second pistons disposed at opposite ends of a piston rod; formation fluid passage means communicates between the formation at the seal pad location and the formation sample chamber via the cylindrical interior portion, with the first piston interposed in the passage and movable to open or close the passage; hydraulic fluid passage means communicates between the means for generating and applying setting pressure to the seal pad means and the second piston; and spring bias means is provided to urge the first piston in the direction to close the formation fluid passage. In accordance with a still further aspect of the invention there is provided a third piston reciprocable within a cylinder which on one side of the third piston is open to the exterior of the tool and which on the other side is open to the valve body cylindrical interior portion which carries the first piston, such that force exerted on the third piston in the direction of closing the seal valve is mechanically transmitted to the first piston, while force exerted on the third piston in the direction of opening the seal valve is independent of the first piston. Another objective of the invention is to provide improved means for maintaining isolation of the formation at the seal pad location when testing in unconsolidated formations. This improved means comprises formation isolation means including hydraulically controlled extendable and retractable seal pad means and backup pad means; the extendable and retractable seal pad means comprising a seal pad, first piston means having a central bore and fixed to the seal pad, and first cylinder means sealingly engaged by said first piston means; closure means sealingly closing the outer end of the first cylinder means and having a central cylindrical bore; a sand screen assembly comprising an elongated piston shaft, sand screen spring means, and piston shaft return bias means; the elongated piston shaft having a first end portion sealingly engaging the closure means central cylindrical bore and movable longitudinally thereof and a first end face, with the first end face being exposed to the well bore annulus when the tool is in operation; the seal pad means having a central opening communicating between the central bore of the first piston means and the earth formation to be tested when the seal pad is set in a well bore; the elongated piston shaft having a second end portion mating with the seal pad central opening and moving longitudinally thereof, and a second end face, with the second end face abutting the earth formation to be tested when the seal pad is set in a well bore; the sand screen spring means comprising a spirally wound spring having numerous turns that are normally separated sufficiently to permit flow of formation fluids as well as sand therethrough, with the inner diameter of the spring loosely mating with the exterior surface of the elongated piston shaft, and means fixing the spring at its outer end portion to the seal pad, with the free portion of the spring extending inwardly along the piston shaft; passage means communicating between the piston shaft second end face and its exterior surface along the length of the spring and beyond the inner end of the spring; abutment means fixed to said piston shaft adjacent the inner end of said passage means, for engaging the spring upon predetermined movement of the piston shaft outwardly toward the earth formation; such that the passage means can become limited to the spaces between the turns of the spring, which spaces are limited to the diameters of sand particles trapped therebetween. In a further aspect of the invention, the passage means are flutes in the exterior surface of the piston shaft. In a further aspect of the invention, the abutment means is a collar fixed to the piston shaft at the inner end of the flutes and mating with or integral with the exterior surface of the piston shaft. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing the tool of the present invention suspended in a borehole, with above ground equipment shown as a block. FIG. 2 is a schematic showing of information that may be produced by a strip chart recorder during operation of the tool. FIGS. 3-7 are schematic longitudinal section views which, when joined end to end consecutively, show from top to bottom the makeup of a tool in accordance with a preferred embodiment of the invention. FIG. 8 is a schematic longitudinal section view showing the sample chamber seal valve incorporated in a pivot joint in accordance with a preferred embodiment of the invention. FIG. 9 is a schematic longitudinal section view showing a sand screen device in accordance with a preferred embodiment of the invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 there is shown a tool 11 of the present invention suspended in a borehole at the location of a formation to be tested, with a seal pad 13 and backup pads 15 in the set condition. The tool 11 is made up of two primary sections which may be termed the upper tool section 17 and the lower tool section 19. As will be hereinafter more fully explained, the lower section 19 is pivotally connected to the upper section 17 so as to provide limited relative pivoting movement about an axis 21 which is normal to the direction of travel of the seal pad 13 and backup pads 15 when they are being extended or retracted. The cable 23 and winch means 25 by which the tool 11 is suspended and traversed along the borehole, as well as the aboveground equipment shown as a block 27, are conventional, and consequently, need not be described in detail herein. FIGS. 3-7 show the entire tool 11 in a series of schematic longitudinal section views, with all parts shown as they would be as the tool 11 is being run into the borehole. The body of the upper tool section 17 may be regarded as made up of several elements, which observing from top to bottom in FIGS. 3-6, are a head sub 29, upper pressure jacket 31, pressure jacket connector sub 33, lower pressure jacket 35, pad block sub 37, and pad block 39. The head sub 29 is threaded at its upper end portion for connection to a conventional cable head (not shown) and is threaded at its lower end portion for connection to the upper end of the upper pressure jacket 31. Suitable conventional cable connectors 41 are provided to make the electrical connections from the cable head through the head sub 29 to the interior of the upper pressure jacket 31. Since the manner of making the necessary electrical connections in the tool is a matter of conventional practice, the details of such connections are not shown or described herein. The lower end of the upper pressure jacket 31 is threadedly connected to the upper end of the pressure jacket connector sub 33. The upper end of the lower pressure jacket 35 mates in sliding engagement with the exterior surface of the pressure jacket connector sub 33 and is secured thereto by bolts. The lower end of the lower pressure jacket 35 is threadedly connected to the upper end of the pad block sub 37 and the upper end of the pad block 39 is fixed to the lower end of the pad block sub 37 by threaded compression connector means. O-rings 105 are provided at suitable locations at the connections of the body elements of the upper tool section 17 to seal out well bore fluids. Apparatus for generating and controlling hydraulic pressure to extend and set seal pad means and backup pad means and to release same, may be referred to as the hydraulic power assembly. The hydraulic power assembly is contained within the portion of the upper tool section 17 shown by FIGS. 3 and 4, and comprises an electric motor 43, a first gear reduction 45, an electromagnetic clutch 47, a second gear reduction 49, a ball screw and ball nut assembly 51, and a hydraulic piston and cylinder assembly 53. The hydraulic power assembly is supported within the upper pressure jacket 31 by the pressure jacket connector sub 33. A primary cylinder 55 of the hydraulic piston and cylinder assembly 53 is threadedly connected at its lower end to the upper end of the pressure jacket connector sub 33 and is threadedly connected at its upper end to the lower end of a bearing assembly retainer structure 57, which in turn is threadedly connected at its upper end to the lower end of a first cylindrical frame structure 59, which is fixed by bolts at its upper flanged end to the lower flanged end of a second cylindrical frame structure 61, which has an upper flanged end. The electric motor 43 (sometimes referred to herein as the setting motor) and its associated first gear reduction 45 are mounted on and fixed by bolts to the upper flanged end of the second cylindrical frame structure 61, with the first gear reduction 45 protruding into the interior of the second cylindrical frame structure 61. The electric motor 43 drivingly engages the first gear reduction 45 which is connected by coupling means 63 to one side of the electromagnetic clutch 47, the other side of which is connected by coupling means 65 to one side of the second gear reduction 49, which in turn is connected on its other side by coupling means 67 to the upper end of a bearing hub 69 of the ball screw and ball nut assembly 51. The electric motor 43 is a reversible 110 volt direct current motor which may typically be of the type manufactured by Globe Industries, Inc., of Dayton, Ohio, model number M100M13. Typically, the first gear reduction 45 may be 14:1 and the second bear reduction 49 may be 55:1. The electromagnetic clutch 47 may typically be of a type manufactured by Magtrol, Inc., of Buffalo, New York, model number FC1090313. The hydraulic piston and cylinder assembly 53 comprises the primary cylinder 55, a secondary cylinder 71, a setting piston 73 and a setting piston return spring 75. The secondary cylinder 71 is disposed within a central bore 77 of the pressure jacket connector sub 33; is fixed therein by a retainer 79 which threadedly engages the lower end of the central bore 77 and protrudes downwardly beyond the retainer 79. The setting piston 73 has a head 81 which sealingly mates with the interior surface 83 of the primary cylinder 55, and an integral tubular extension 85 which protrudes into said secondary cylinder 71 and sealingly engages the interior surface 87 of the secondary cylinder 71 adjacent to entrance thereto. The setting piston 73 has a central bore 89 which extends throughout its length. The ball screw and ball nut assembly 51 comprises the bearing assembly retainer structure 57, the bearing hub 69, a ball screw 91 and a ball nut 93. The bearing hub 69 is secured by suitable means for rotation within the bearing assembly retainer structure 57 and has a threaded upper extension portion 95 upon which there is mounted an actuator nut 97 which carries a limit switch actuator 99. The travel of the actuator nut 97 is related to the travel of the setting piston 73 so as to limit the latter in both upward and downward directions by actuating a respective limit switch 101, 103 to open the circuit to the setting motor 43. The ball screw 91 is fixed at its upper end to the lower end of the bearing hub 69 and extends downwardly the full length of the primary cylinder 55 and protrudes partially into the setting piston central bore 89. The ball nut 93 engages the ball screw 91 and is threadedly fixed at its lower end to the head 81 of the setting piston 73. The setting piston return spring 75 bears at its upper end against the bearing assembly retainer structure 57 which closes the upper end of the primary cylinder 55, and bears at its lower end on the head 81 of the setting piston 73. Apparatus for conducting various formation tests and for providing and controlling flow valve means may be referred to for convenience as the mini-sample apparatus. The mini-sample apparatus is contained within the portion of the upper tool section shown by FIGS. 5 and 6, and comprises an electric motor 107, a gear reduction 109, a ball screw and ball nut assembly 111, and a mini-sample cylinder and piston assembly 113. The mini-sample apparatus is supported within the lower pressure jacket 35 by the pad block sub 37. A third cylindrical support structure 115 is threadedly connected at its lower end to the upper end portion of the pad block 39 and is threadedly connected at its upper end to the lower end of a fourth cylindrical support structure 117. The electric motor 107 (sometimes referred to herein as the mini-sample motor) and its associated gear reduction 109 are mounted on and fixed by bolts to the upper end of the fourth cylindrical support structure 117, with the gear reduction 109 protruding into the interior of the fourth cylindrical support structure 117. The electric motor 107 drivingly engages the gear reduction 109 which is connected by coupling means 119 to the upper end of a bearing hub 121 of the ball screw and nut assembly 111. The mini-sample electric motor 107 may be of the same type as the setting motor 43. Typically, the mini-sample motor gear reduction 109 may be 445:1. The mini-sample piston and cylinder assembly 113 comprises a primary piston structure 123, a primary cylinder 125, a floating piston 127, and a flow line valve body 129. The primary piston structure 123 comprises a piston head portion 131 and a cylindrical housing portion 133 having first and second central bores 135, 137. The piston head portion 131 is threadedly connected to the lower end of the cylindrical housing portion 133 which is also the lower end of the first central bore 135. The piston head portion 131 is reciprocable within the primary cylinder 125 formed by a central bore in the lower end of the pad block sub 37. The upper end of the first central bore 135 is sealingly closed by a pressure sensor adapter 139. The second central bore 137 has a threaded connection at its upper end to the ball nut 141 of the ball screw and ball nut assembly 111, and the second central bore 137 receives the ball screw 143 of the ball nut and screw assembly 111 as the ball nut 141 is moved upwardly. The flow line valve body 129 is a generally cylindrical structure having a flanged upper end portion merging with an exterior threaded portion which in turn merges with cylindrical exterior sealing surfaces. The flow line valve body has a central bore 145, an annular exterior groove 147 disposed between said sealing surfaces, and flow passages communicating between the annular groove 147 and the central bore 145. The pad block 39 is provided a bore 149 for threadedly receiving said flow line valve body 129 and matingly receiving said sealing surfaces. The floating piston 127 has a head portion 151 in sealing engagement with and reciprocable within the first central bore 135 of the primary piston structure 123 and an integral downwardly extending tubular extension 153 having an exterior sealing surface 155 at its lower end portion which is matingly received by the flow line valve body central bore 145. The upper surface of the floating piston head portion 131, the lower surface of the pressure sensor adapter 139 and the portion of the primary piston structure first central bore 135 between these surfaces formed a mini-sample chamber 159 having variable volume, as will be hereinafter explained. The floating piston 127 has a fluid passage 161 communicating between the mini-sample chamber 159 and the lower end of the pad block bore 149. The ball screw and ball nut assembly 111 comprises a bearing assembly retainer structure 157, the bearing hub 121, the ball screw 143, and the ball nut 141. The bearing hub 121 is secured by suitable means for rotation within the bearing assembly retainer structure 157. The ball screw 143 is fixed at its upper end to the lower end of the bearing hub 121 and extends downwardly through the ball nut 141. A limit switch actuator 163 is mounted on the primary piston structure 123 and is movable with the ball nut 141 between upper and lower limit switches 165, 170. The limit switches 165, 170 are connected in the power supply circuit of the mini-sample motor 107 so as to stop the motor when actuated. Thus, the travel of the ball nut 141 (and hence the primary piston structure 123) is limited. A series of longitudinally extending cam notches 169 are provided on the exterior surface of the upper end portion of the primary piston structure for coaction with the cam actuator 171 of a microswitch 173 which is mounted to the third cylindrical support structure 115. The microswitch 173 produces an output pulse each time the cam actuator 171 traverses a cam notch 169. Each cam notch 169 represents an increment of mini-chamber 159 volume (typically 2 c.c.). The tool 11 has an electronics section 175 comprising various components mounted on a chassis 177 located in a space between the upper end of the mini-sample motor 107 and the lower end of the secondary cylinder 71 of the hydraulic piston and cylinder assembly 53. The electronics section chassis 177 is secured at its upper end to the lower end portion of the secondary cylinder 71. A hydraulic fluid or seal pad setting pressure sensor 179 is mounted in the end of the secondary cylinder 71. A formation fluid pressure sensor 181 is mounted in the pressure sensor adapter 139 of the mini-sample apparatus. Power (110 volts direct current) is supplied from the aboveground equipment via cable 23 and connectors 41 separately to each of the setting motor 43 and the mini-sample motor 107 in series with respective limit switches 101, 103 and 163, 165, so that each motor 43, 107 can be separately controlled by the aboveground operator. Power (26 volts direct current) is also supplied from the aboveground equipment to the electronics section 175, in series with the energizing coil of the electromagnetic clutch 47, so that the electromagnetic clutch 47 is de-energized to disengage when and if there is a failure in the 26 volt direct current power supply. The electronics section 175 includes a power supply and amplifiers for the pressure sensors 179, 181 and also a power supply and amplifier for the circuit of microswitch 173. Output signals from each pressure sensor amplifier and the microswitch circuit amplifier are transmitted to the aboveground equipment via the cable 23. Since the electronics section, the power supply conductors and various electrical connections are matters within the scope of conventional practice, these are not shown or described in detail herein. An inner cylindrical jacket 183 is received within the lower pressure jacket 35 and is matingly and sealingly received at its upper end by a cylindrical external surface portion 185 of the pressure jacket connector sub 33 and is further matingly and sealingly received at its lower end by an exterior cylindricl surface 187 at the upper end of the pad block sub 37. The pad block 39 carries a sealing pad assembly 189, upper and lower backup pad assemblies 191, 193 and an equalizer valve assembly 195. The sealing pad assembly 189 comprises a sealing pad 197, sealing pad retainer 199, sealing pad plate 201, upper and lower sealing pad guide rods 203, 205, sealing pad piston 207, sealing pad piston plug 209, and sealing pad cylinder 211. The sealing pad 197 is made of a resilient material such as rubber, which typically may be 60-90 durometer nitrile rubber, and has a generally rectangular shape, with some curvature in transverse section so as to generally conform to the borehole wall curvature. The sealing pad plate 201 is a metal plate that can cover a large portion of the inner surface of the sealing pad 197. The upper and lower sealing pad guide rods 203, 205 are secured by bolts to the sealing pad plate 201 adjacent its respective upper and lower edges and are reciprocable in respective mating bores (not shown) in the pad block 39. The sealing pad retainer 199 is generally cylindrical having a flanged outer end, a cylindrical exterior portion 200 matingly received by a sealing pad central bore, and an exterior threaded portion at its inner end which engages internal threads at the outer end of the sealing pad piston 207. When the sealing pad retainer 199 is in place, the sealing pad 197 is clamped between the retainer flanged outer end and the sealing pad plate, and the sealing pad plate is clamped between the sealing pad inner surface and the outer end face of the sealing pad piston 207. Thus, the sealing pad 197 and sealing pad plate 201 are securely fixed relative to the sealing pad piston 207. The sealing pad retainer 199 has a cylindrical bore 202 at its inner end portion which merges with a threaded intermediate bore 204 of smaller diameter which in turn merges with an outer end bore of still smaller diameter, for a purpose to be hereinafter explained. The sealing pad piston 207 has a first exterior cylindrical surface 206 that extends over about half its length from the center portion outwardly toward the sealing pad 197 and a second cylindrical exterior surface 208 of smaller diameter extending from the center portion inwardly to the inner end. The sealing pad piston 207 has a cylindrical central bore 210 extending between the internal threads 222 at the outer end portion and internal threads 224 at the inner end portion, which cylindrical central bore 210 merges with and has the same diameter as the cylindrical bore 202 at the inner end of the sealing pad retainer 199. The pad block 39 has a central transverse bore 213 having a first cylindrical portion 212 matingly and sealingly receiving the first exterior cylindrical surface of the sealing pad piston 207 and merging with a second cylindrical portion 214 of increased diameter for providing a fluid flow passage to and around the sealing pad piston 207, and merging with a third cylindrical portion 216 of further increased diameter for receiving a cylindrical exterior portion of the sealing pad cylinder 211, and merging with a fourth cylindrical portion 218 of further increased diameter for matingly and sealingly receiving a second cylindrical exterior portion of the sealing pad piston 207, and merging with a fifth cylindrical threaded portion 220 of further increased diameter for receiving a threaded exterior portion of the sealing pad cylinder 211. The sealing pad piston plug 209 has a cylindrical exterior portion 215 that matingly and sealingly engages a first cylindrical interior surface 217 of the sealing pad cylinder 211 and merges with a threaded cylindrical portion 219 of reduced diameter which engages the threads 224 at the inner end portion of the sealing pad piston 207. The threaded cylindrical portion 219 has a plurality of longitudinally extending grooves 221 which extend to communicate with corresponding lateral bores 223 to provide fluid passages between the second exterior cylindrical surface 208 of the sealing pad piston 207 and its interior. The sealing pad cylinder 211 has a second interior cylindrical surface 225 of lesser diameter than the first cylindrical interior surface 217 and which matingly and sealingly engages the second exterior cylindrical surface 208 of the sealing pad piston 211. A shoulder 227 on the exterior surface of the sealing pad piston at the juncture of the first and second exterior cylindrical surfaces 206, 208 of the sealing pad piston 211 abuts the inner end surface of the sealing pad cylinder 211 to provide a stop for the sealing pad piston 211 in the retracting direction. The upper backup pad assembly 191 comprises a piston shaft 229, a backup pad 231, a seal plug 233, and a guard pad 235. A transcerse bore 237 in the pad block 39 receives the piston shaft 229 and seal plug 233. The backup pad 231 is made of metal; is generally disc shaped; and is fixed to the outer end of the piston shaft 229. The seal plug 233 is fixed to the pad block 39 at the entrance to the transverse bore 237 by threads 239 and has a circumferential groove 241 in its exterior surface to provide a fluid passage. The piston shaft 229 matingly and sealingly engages a first interior cylindrical portion 243 of the seal plug 233 located at the seal plug outer end portion; which interior cylindrical portion 243 merges with a second interior cylindrical portion 245 of greater diameter, which second interior cylindrical portion 245 in turn merges with an interior cylindrical portion 247 of the transverse bore 237. The guard pad 235 is sealingly fixed to the pad block exterior surface by bolts and serves to protect the sealing pad 197. The guard pad 235 has a central cavity 249 which receives the inner end portion of the piston shaft 229. The lower backup pad assembly 193 is like the upper backup pad assembly 191 except that its seal plug 251 does not incorporate circumferential groove 241 and consequently does not provide the associated fluid passage. The equalizer valve assembly 195 comprises a piston 253, a seal ring 255, a retainer plug 257 and a bias spring 259. The pad block 39 is provided a bore 261 for receiving the equalizer valve assembly 195. The piston 253 matingly and sealingly engages adjacent its inner end a portion 263 of the pad block bore 261 and adjacent is outer end a central bore 265 of the seal ring 255. The inner end of the piston is exposed to a hydraulic fluid flow passage, while the outer end is exposed to well bore fluid. The retainer plug 257 threadedly engages the outer end portion of the pad block bore 261 to hold the seal ring 255 in place within a portion of the pad block bore 261. The bias spring 259 bears at one end on the seal ring 255 and at the other end on a shoulder on the piston 253, so as to urge the piston inwardly for a purpose to be hereinafter explained. The lower tool section 19, with the exception of the pivot assembly 277, is of a conventional design and consequently will be described only briefly herein. The body of the lower tool section 19 may be regarded as made up of several elements, which, observing from top to bottom in FIG. 7, are a bleed off sub 267, a formation sample chamber 269, a chamber connector sub 271, a cushion chamber 273, and a bull plug 275. The bleed off sub 267 is threadedly connected at its lower end portion to the upper end portion of the formation sample chamber 269 which is threadedly connected at its lower end portion to the upper end portion of the chamber connector sub 271 which is threadedly connected at its lower end portion to the upper end portion of the cushion chamber 273 which is threadedly connected at its lower end portion to the bull plug 275. The bleed off sub 267 has a transverse bore 279 which on one side carries a seal plug 281 and on the other side carries a bleed off valve 283. A formation sample fluid passage 285 in the bleed off sub communicates from the pivot assembly 277 via the bleed off valve 283 to the volume of the sample chamber interior above a sample chamber piston 287. The sample chamber volume below the sample chamber piston 287 contains water which is forced via a choke assembly 289 carried by the chamber connector sub 271 into the volume of the cushion chamber 273 above a cushion chamber piston 291, as the sample chamber piston 287 is moved downwardly. The cushion chamber volume below the cushion chamber piston 291 contains air. A separate fluid passage 293 communicates between the lower end of the formation sample chamber 269 and the upper end of the cushion chamber 273 via the chamber connector sub 271 and a check valve 295. Suitable seals are provided within the lower tool section by various O-rings 297. As hereinbefore stated, the lower tool section 19 is pivotally connected to the upper tool section 17 so as to provide limited relative pivoting movement about an axis 21 which is normal to the direction of travel of the seal pad 13 and backup pads 15 when they are being extended or retracted. The pivot assembly 277 (see FIG. 8) comprises first and second upper tool section pivot bearing protrusions 299, 301, a lower tool section pivot bearing protrusion 303, and a formation sample chamber seal valve assembly 305 which comprises a seal valve body 307, a piston rod 309 having first and second pistons 311, 313 carried on its opposite ends, a bias spring 331, a third piston 315, and a retainer cylinder 317. The first and second upper tool section pivot bearing protrusions 299, 301 are integral with and extend downwardly from the lower end of the pad block 39 in parallel juxtaposed relation and have respective coaxial transverse bores 319, 321 of equal diameter. The lower tool section pivot bearing protrusion 303 is integral with and extends upwardly from the upper end of the bleed off sub 267 and into the slot 322 formed between the first and second protrusions 299, 301. The lower tool section pivot bearing protrusion 303 has a transverse bore 325 coaxial with and of the same diameter as the respective bores 319, 321 of the first and second protrusions 299, 301. These transverse bores form the bearing box or bearing surfaces for the pivot pin or journal of the pivot assembly 277, which in the embodiment shown, is the seal valve body 307. The seal valve body 307 has a cylindrical exterior surface 327 that is sealingly and matingly received within the transverse bores 319, 321 325. The transverse bore 321 of the second bearing protrusion 301 does not extend all of the way through the protrusion, and a chamber is formed at the inner end portion of the seal valve body 307 which communicates with a hydraulic fluid flow passage 329 in the pad block 39. The retainer cylinder 317 threadedly and sealingly engages the outer portion of the transverse bore 319 and has a cylindrical interior portion 343 which matingly and sealingly engages the third piston 315. The seal valve body 307 has a first cylindrical interior surface 333 that matingly and sealingly receives the second piston 313 and a second cylindrical interior surface 335 of smaller diameter that matingly and sealingly receives the first piston 311. Fluid passage means 337 is provided at the inner end portion of the retainer cylinder to communicate with a formation fluid flow passage 339 in the pad block 39. Another fluid passage means 341 is provided in the seal valve body 307 to communicate between the valve body interior and a formation fluid flow passage 285 in the bleed off sub 267. When the tool 11 is operated in a borehold where unconsolidated formations may be encountered, the sand screen assembly 345 shown by FIG. 9 is utilized. To install the sand screen assembly 345, the sealing pad piston plug 209 (see FIG. 6) is removed and the sand screen assembly 345 is inserted in the cavity made up of the cylindrical bore 202 of the sealing pad retainer 109, the cylindrical central bore 210 of the sealing pad piston 207 and the space vacated by the piston plug 209. The sand screen assembly 345 comprises a sand screen plug 347, an elongated piston shaft 349, a sand screen spring 351 and a bias spring 353. The sand screen plug 347 is like the sealing pad piston plug 209 that it replaces, except that the sand screen plug 347 has a central bore 355 for matingly and sealingly receiving the outer portion of the piston shaft 349 for reciprocable movement therein. The outer end face of the piston shaft 349 is thus exposed to the well bore when the tool 11 is in operation. The inner end portion of the piston shaft 349 is received by the outer end bore of the sealing pad retainer 199, so that the outer end face of the piston shaft 349 can move into abutting relation with the earth formation being tested when the tool 11 is in operation. The bias spring 353 bears at one end on a shoulder formed at the juncture of the sealing pad retainer cylinder bore 202 and the threaded intermediate bore 204, and at the other end on a ring 357 which is held against outward movement by roll pins 359 carried by the piston shaft 349. When the bias spring 353 is relaxed, the piston shaft 349 is positioned such that its outer end is flush with the outer face of the sand screen plug 347. The sand screen spring 351 is a spirally wound spring having numerous turns that are normally separated sufficiently to permit flow of formation fluids as well as sand therethrough. The inner diameter of the sand screen spring 351 mates loosely with the exterior surface of the piston shaft 349 and the sand screen spring is secured at its inner end by threading onto the threaded intermediate bore 204 of the sealing pad retainer 199. The sand screen spring 351 typically may have fifty turns in about 11/2" of length when relaxed and shortens to about 11/8" when fully compressed. The piston shaft 349 is provided passage means (shown as spiral flutes 361) communicating between the outer end face of the piston shaft 349 and its exterior surface along the length of the sand screen spring 351 and a short distance (typically about 1/4") beyond the inner end of the sand screen spring 351. Abutment means, shown as a collar 363, is fixed to the piston shaft 349 adjacent the inner end of the passage means 361, for engaging the sand screen spring 351 upon predetermined movement of the piston shaft 349 outwardly toward the earth formation. Passage means 365 are provided between the outer end face of the piston shaft 349 and the spiral flutes 361. The inner and outer end faces of the piston shaft 349 have equal diameters, so that the piston shaft 349 will not move as the tool 11 is being traversed into the borehole, since well bore fluid pressures on the end faces of the piston 349 are balanced. When the tool 11 has reached the test site and the sealing pad assembly 189 has been extended and set in sealing engagement with the formation and the volume of the mini-sample chamber 159 has been expanded, then the pessure force on the inner face of the piston shaft 349 will be less than that on the outer face, so that the piston shaft 349 will be continually urged into contact with the formation. Initially, the turns of the sand screen spring 351 will be separated and formation fluid including sand can pass through the turns of the sand screen spring 351 and also through the space between the outer end of the sand screen spring 351 and the inner end of the collar 363. As the unconsolidated formation is eroded, the piston shaft 349 moves inwardly so that the inner end face of the collar 363 abuts the outer end of the sand screen spring 351 and compresses same. The sand screen spring 351 will not fully compress because of sand particles that become trapped between the spring turns. Thus, eventually, the only flow path from the formation via the piston shaft passage means 365 to the interior of the sealing pad piston 207 is between the compressed turns of the sand screen spring 351. Since no more sand can pass between the turns of the sand screen spring 351, the formation ceases to erode and only formation fluid is passed through the sand screen spring. When the formation test is completed and well bore fluid pressure again acts on the inner end of the piston shaft 349, the pressure forces on the ends of the piston shaft 349 will again be balanced, allowing the bias spring 353, which was compressed by movement of the piston shaft 349 inwardly, to move to its relaxed position, returning the piston shaft 349 to its original position. As the piston shaft 349 returns toward its original or initial position, the turns of the sand screen spring 351 are wiped by the spiral flutes 361 to clean off the sand particles. It will be convenient to describe the operation of the tool 11 with reference to FIG. 2 which schematically presents certain information that is produced by a strip chart recorder and is observed by the operator at the aboveground equipment location during operation of the tool. In FIG. 2, the trace A represents hydraulic pressure sensed by hydraulic fluid pressure sensor 179 on a scale of 0-5,000 p.s.i. The trace B represents the pulses produced each time the cam actuator 171 traverses a cam notch 169. In the embodiment shown, each pulse represents a two c.c. volume increment of mini-chamber 159 volume. The digital printout column C shows in p.s.i., at predetermined time intervals (typically 5 seconds), the pressure sensed by formation fluid pressure sensor 181. Trace D represents the pressure sensed by the formation fluid or hydrostatic pressure sensor 181 on a scale of 0-10,000 p.s.i.; while trace E represents the pressure sensed by the formation fluid pressure sensor 181 on a scale from 0-1,000 p.s.i. As the tool 11 is run into the borehole, all parts are in the positions shown by FIGS. 3-7. When the tool 11 is stopped at the depth of the earth formation to be tested, the operator energizes the setting motor 43 for rotation in the direction to cause ball nut 93 to move upwardly, bringing with it the setting piston 73. As the setting piston 73 moves upwardly, hydraulic fluid is forced out of the primary cylinder 55 and via various fluid passage means to the interior of the sealing pad piston 207 and the interiors of the upper and lower backup pad assemblies 191, 193, thus causing the sealing pad 197 and the backup pads 231 to be extended into contact with the wall of the well bore. This hydraulic fluid flow path can be traced from the interior of the primary cylinder 55 through the ball nut 93, through the setting piston central bore 89 to the interior of the secondary cylinder 71 and via a passage 367 to the space between the lower pressure jacket 35 and the inner cylinder jacket 183 to a hydraulic fluid pressure passage 369 in pad block sub 37 and through a connector valve assembly 371 to a hydraulic fluid passage 373 in pad block 39. This hydraulic fluid flow path is isolated by means of various o-ring seals. When the hydraulic fluid pressure reaches a value which is about 1,5000 p.s.i. above the well bore pressure, then the sealing pad 197 is considered to be set, thus isolating the formation at the sealing pad location. In FIG. 2 it can be seen that this event occurs at the point 375 of trace A and at a readout of about 1,623 pounds on trace C. When the point 375 is observed by the operator, he de-energizes setting motor 43. Next, the operator energizes the mini-sample motor 107 for rotation in the direction to cause ball nut 141, and consequently primary piston structure 123, to move upwardly. Upward movement of the primary piston structure 123 causes the volume of mini-sample chamber 159 to begin to increase. The mini-sample chamber communicates with the formation being tested at the seal pad location via passage means which can be traced from the mini-sample chamber 159 through the floating piston fluid passage 161 to the circumferential groove 241 in seal plug 233, through a passage in the pad block 39 to the pad block bore 261 for the equalizer valve assembly 195 and through a further passage in pad block 39 to the third cylindrical portion 216 of the pad block central transverse bore 213 and through openings in the wall of sealing pad cylinder 211 and through bores 223 and sealing pad piston plug 209 and the grooves 221 in threaded cylinder portion 219 of sealing pad piston plug 209 to the interior of the sealing pad piston 207 which is exposed to the earth formation at the sealing pad location. This formation fluid path is isolated by means of various o-ring seals, so long as the equalizer valve 195 is closed. The pressure forces acting on the upper end of the floating piston 127 are always greater than those acting on its lower end because of unequal surface areas, and consequently the floating piston is always urged downwardly by the differential pressure forces. Thus, the floating piston 127 remains in its extreme downward position as the primary piston structure 123 is moved upwardly. In the example shown by FIG. 2, the operator permits the primary piston structure 123 to move upwardly until five pulses have been generated on trace B, showing that the mini-sample chamber volume 159 has increased to 10 c.c. Observing trace E of FIG. 2, it will be seen that the fluid pressure in the mini-sample chamber 159, as sensed by the formation fluid pressure sensor 181 rapidly decreases as the mini-sample chamber volume is increased. As seen by the pressure readout in column C, the mini-sample chamber pressure has decreased from 1,623 p.s.i. to 1,087 p.s.i. and soon thereafter increases and stabilizes at about 1,279 p.s.i. (see also trace E). This is the "shut-in" pressure of the formation being tested. It will be observed that it was only necessary for the operator to open the mini-sample chamber sufficiently to cause the pressure therein to drop to a point considered to be below the likely formation shut-in pressure and then de-energize the mini-sample motor 107 and wait for the mini-sample chamber pressure to build up and stabilize, at which point the formation "shunt-in" pressure will have been reached. When the formation being tested has a low permeability, only a small amount (perhaps only 2 c.c.) of formation fluid need be drawn into the mini-sample chamber to achieve formation "shunt-in" pressure. If it were necessary to wait for a large test sample chamber to fill before formation "shunt-in" pressure is achieved, this could take a long time in the case of low permeability formations. An important feature of the present invention is the provision for a variable volume mini-sample chamber which can be monitored at aboveground equipment and controlled at the will of an operator. Next, the mini-sample motor 107 is again energized in the direction to continue upward movement of the ball nut 141 and consequently the primary piston structure 123, generating a second series of pulses on trace B of FIG. 2. After a predetermined upward movement of the primary piston structure 123, a shoulder on the upper end of piston head portion 131 engages a shoulder on the lower side of the head portion 151 of the floating piston 127, forcing the floating piston 127 to move upwardly away from seal means 377 to open a flow passage from the floating piston fluid passage 161 to the groove 147 in the flow line valve body 129 and through passage means including fluid flow passage 339 in the pad block 39 and via the seal valve 305 and a further formation fluid flow passage 285 in the bleed off sub 267 and through the bleed off valve 283 and further fluid flow passage 285 into the formation sample chamber 269. It should be noted (see FIG. 8) that the sample chamber seal valve 305 is normally urged to its closed position under the force of bias spring 331 because the second and third pistons 313, 315 have the same diameter and are exposed to well bore pressure. The piston 313 is exposed to hydraulic fluid via the hydraulic fluid flow passage 329. The piston 313 is subjected to hydraulic fluid pressure generated by the action of the setting motor 43 and consequently the piston rod 309 and first piston 311 are moved outwardly to open the seal valve 305 thus permitting formation to flow from passage 339 to the interior of the seal valve body 307. The equalizer valve inner end face is also subjected to hydraulic fluid pressure generated by the action of the setting motor 43 and is moved to the closed position by such hydraulic fluid pressure. The opening of the formation fluid flow line (upon sufficient upward movement of floating piston 127) results in a drastic pressure drop within the mini-sample chamber as sensed by the formation fluid pressure sensor 181. This event is observed by the operator at point 379 on trace A and also in the pressure readout column C where the pressure reading suddenly drops from 1,183 p.s.i. to 159 p.s.i. At this point, the operator stops the mini-sample motor 107 (or it is stopped by a limit switch) and waits for the formation sample chamber 269 to fill. As the formation sample chamber 269 is filled, the formation pressure readings (in column C of FIG. 2) gradually increased until the formation "shut-in" pressure is again reached (when the column C readouts show about 1,272 p.s.i.). After the formation "shut-in" pressure has again been reached, indicating that the formation sample chamber 269 is full, the operator again energizes mini-sample chamber motor 107 to rotate in the reverse direction, thus moving the primary piston structure 123 downwardly, permitting the floating piston 127 to move downwardly to its lower most position, thus closing the formation fluid flow passage through the flow line valve body 129. Then, downward movement of the primary piston structure 123 is continued in order to expel the formation sample fluid from the mini-sample chamber 159. The operator, monitors the volume condition of the mini-sample chamber 159 by watching the series of pulses on trace B of FIG. 2. Next, the operator energizes the setting motor 43 in the reverse direction to cause the setting piston 73 to move downwardly, increasing the volume of the primary cylinder 55 thus reducing the hydraulic fluid pressure. This hydraulic fluid pressure reduction permits the equalizer valve 195 to open, and the seal valve 305 to close. Thus, the formation sample chamber 269 is sealed. Also, well bore fluid is admitted to the interior of the sealing pad piston 207 and consequently onto the formation at the sealing pad location, which results in equalization of pressures on the sealing pad 197 causing it to release its contact with the formation. Differential pressures on the sealing pad assembly 189 and the upper and lower backup pad assemblies 191, 193 cause them to retract to their running in positions. The rapid reduction in hydraulic pressure resulting from the reversing of the setting motor 43 may be noted on trace A of FIG. 2 between the points 381 and 383. The operator can also notice from column C of FIG. 2 that the equalizer valve has opened when the pressure readout returns to normal well bore pressure (at about 1,495 p.s.i.). It should be noted that the herein disclosed arrangement of mini-sample apparatus makes it possible to open and close the flow line path at the flow line valve body 129 and vary the volume of the mini-sample chamber 159 independently of any other function of the tool 11. This makes possible certain operator options. First, as hereinabove mentioned, the waiting time for achieving formation "shut-in" pressure can be greatly reduced. Second, the formation fluid flow line can be opened and re-closed during a sample test in order to unplug the flow path by injecting fluid in the mini-sample chamber 159 back through the system and into the formation at the seal pad location. Third, a formation "shut-in" pressure test can be performed at any time either while the formation fluid sample chamber 269 is being filled, or thereafter, by closing the formation flow line passage at the flow line valve body 129. Further, all of the functions above-mentioned can be performed independently of the sealing pad setting function.

A tool for testing earth formations in boreholes provides a failsafe function for retracting the sealing pad elements of a formation isolation device, in the form of elements operable in response to failure of downhole power supply for the tool to effect release of hydraulic setting pressure on the seal pad elements. The tool further provides a formation mini-sample chamber of variable volume with elements permitting aboveground monitoring and control of same independently of any other tool function. The mini-sample chamber control device also controls the operation of a formation fluid sample flow line valve. The tool is divided into upper and lower pivotable sections to alleviate the problem of becoming differentially stuck. A unique pivot structure incorporating sample chamber seal valve assembly, is provided. A unique sand screen device is provided to permit the tool to function when working wih unconsolidated formations.

You are an expert at summarizing long articles. Proceed to summarize the following text: COPYRIGHT NOTICE [0001] A portion of the disclosure of this patent document, including Appendices, contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. BACKGROUND OF THE INVENTION [0002] This invention relates generally to an apparatus (an article of manufacture) and method of use. The present invention particularly relates to structure restraint systems and accessories used in conjunction therein. The present invention more particularly relates to a device, system and method of using a structure restraint system to solve the problem of roof and/or structure damage due to inclement weather, natural forces and acts of God. DESCRIPTION OF THE PRIOR ART [0003] Internal restraint systems are commonly used in modern buildings to resist wind, earthquake and other loads. Especially in south Florida and the Gulf of Mexico, which had record hurricanes in 2004, the building codes are increasingly becoming required to enable buildings and structures for 140 MPH (miles per hour) wind loads. [0004] Accordingly, it is understood that one skilled in the art would know that most new building codes in high-wind areas require the structure to be physically connected contiguously from the roof to the foundation. The old art uses “hurricane clips” to tie the rafters or trusses to the top of the bearing wall and the bearing wall then anchored to the foundation. This generally works well but not when needed in emergencies during the time of high wind and/or other natural forces exceed normal design specifications, i.e. the few days during which the hurricane path is close enough to impart destructive wind forces exceeding design strength. It is expensive and inefficient to design and build buildings and/or structures (houses, offices, warehouses, storage buildings, industrial plants, retail stores, aircraft hangars, etc.) for the maximum need (140 MPH or higher) when this strength is only needed a rarely for a few days at a time. Additionally, older homes were designed to withstand much lower speed winds and need an external emergency restraint system to enhance the roof's resistance to 140 MPH wind force, such as this invention accomplishes. [0005] Also, previous devices and systems also do not prevent the loss of typical residential roof shingles. The problem to be solved is preventing roof shingles from being “stripped” from a sloped roof by the high winds for short periods of time. Thus, a need exists in the industry for a device and system that may be quickly installed externally to be used in these relatively short durations of high climatic forces. Versions of this new and useful invention solve this need. [0006] U.S. Pat. No. 6,722,085 discloses a Mobile Home Tie-Down Apparatus. [0007] No prior art is known to this inventor that discloses a selectably attachable emergency device and/or system installed externally over the structural skeleton that makes it possible to restrain roof shingles, roofs and buildings/structures under emergency climatic conditions while attached, then released, removed and stored for future use during normal climatic conditions. Since versions of the device and system are only utilized during the actual times needed, the aesthetics of the building/structure are unchanged during average wind conditions. This new and useful invention solves the problems of securely restraining roof shingles, roofs, and buildings/structures, alone or in combination, during emergency climatic periods when needed while not affecting the artistic elements of the building/structure when not needed. BRIEF SUMMARY OF THE INVENTION [0008] It is an object of the benefits and features of versions of this invention to help prevent the “stripping” of shingles from building/structure roofs during high winds. [0009] It is another object of the benefits and features of versions of this invention to help restrain the roof, roof system and building/structure during high winds and other types of inclement weather with a releasably attached external structure restraint system that may be removed and stored when not needed. [0010] At least one, some or all of the objects of this invention are achieved, in several embodiments, with this new and useful emergency external structure restraint device and system. This external structure restraint device and system is lightweight, compact when stored and of simple construction that is easy to make and use. BRIEF DESCRIPTION OF THE DRAWINGS [0011] In the manner in which the above-recited and other advantages and objects of versions of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: [0012] FIG. 1 is a sectional view of an embodiment of the external structure restraint device and system constructed in accordance with one embodiment of the present invention, showing an eave with no overhang. Eaves with overhangs may also be used. [0013] FIG. 2 is a plan view of an embodiment of the external structure restraint device and system constructed in accordance with one embodiment of the present invention. [0014] FIG. 3 is a sectional view of an alternate embodiment showing the plurality of earth anchors connected to tension members attached to the external roof net, tightened for emergency use. [0015] FIG. 4 is a plan view of an alternate embodiment showing the plurality of earth anchors connected to tension members attached to the external roof net, tightened for emergency use. [0016] FIG. 5 is a plan view showing the continuous ridge cushion(s) and continuous eave cushion(s) under the external roof net. [0017] FIG. 6 is a sectional view of an arch-type structure with the external roof net used with or without additional tension members and earth anchors or alternately earth anchoring into the foundation of the structure. [0018] FIG. 7 is a sectional view of a structure with crawl space on pier foundations with at least one earth anchor set in a predetermined location upwind to resist a particular wind force vector. [0019] While the present invention will be described with reference to the details of the embodiments of the invention shown in the drawings (and some embodiments not shown in the drawings), these details are not intended to limit the scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0020] The apparatus of the invention is conveniently fabricated in the preferred embodiment by conventional and standard methods of fastening, weaving, winding, seaming, installing, joining and finishing in the metal, wire, netting, textile and earth anchoring fabrication arts using conventional and standard materials. [0021] For example, the external structure restraint device and system and incorporated components may be fabricated from wood, aluminum, steel, stainless steel and/or other like metals or any other suitable material as will be readily apparent to one of ordinary skill in the art. Versions of the present invention (or components of) may also be fabricated in best mode from non-metallic materials for lighter weight, reduced cost and resistance to corrosion. These non-metallic materials include, among others, conventional polymers such as, for example, polystyrene, polycarbonate, polyurethane, polyethylene, phenol formaldehyde resins, polybutylene, Teflon and the like. [0022] Plastics (any one of a large and varied group of materials consisting wholly or in part of combinations of carbon with hydrogen, oxygen, nitrogen and other organic and inorganic elements; while solid in the finished state, at some stage in its manufacture, it is made liquid, and thus capable of being formed into various shapes, usually through the application of heat and/or pressure), such as monomer (one unit—the building block for polymer molecules) or polymer (many monomer units strung together to make long molecules) used in polymerization (the process of combining short molecules to make long molecules) may be used. [0023] Thermoplastics (plastics that can be repeatedly softened and hardened by heating and cooling) as well as Thermosets (plastics that are cross-linked during polymerization and cannot be softened without degrading some linkages) may also be used. [0024] Thermoplastic resin types such as crystalline (thermoplastics containing areas of dense molecular alignments known as crystallinity), amorphous (thermoplastics with no crystallinity in the solid state), liquid crystal polymers (LCPs) (stiff, rod-like structures organized in large paralleled arrays in both melted and solid states) may also be used. [0025] All components may be referenced in plural for convenience, as only at least one of all components are necessary, if desired, for proper operation and use in other embodiments. Ideally, all components (or some components) are fabricated from non-metallic materials as previously mentioned above. Other materials and methods that can be used are stainless steel cables, textile threads made from materials standard in the textile industry such as nylon webbing, nylon thread, Kevlar thread, cotton thread, canvas material, nets and/or netting materials made from any of the above-referenced materials, which is meant to be illustrative and not intended to be limiting as to the types of materials that may be used to practice versions of the invention. These materials may be formed into thread, strap, rope, net, web, band, cord, string, leash, belt, braid, mesh and pliable membranes. [0026] The earth anchor may be fabricated from suitable metal in the form of screw-anchors for mobile homes, flap-type anchors, concrete foundation or other type means for anchoring. For example, an earth anchor such as one available by General Supply, 3902 Hanna Circle—Suite A, Indianapolis, Ind. 46241, Phone: (317) 856-4300, Toll Free: (800) 479-2754, Fax: (317) 856-1012, Email: [email protected], the ¾″×30″ E-Z Set Anchor by Tie Down Engineering. Other Tie Down Engineering, Inc. (5901 Wheaton Drive, Atlanta, Ga. 30336) models that may be used are models MI 2H, MI 2H6, MI 22, MRA, MRAX 48 and related accessories, which are listed as illustrative only and not intended to be limiting as to the types of earth anchors that may used to practice versions of the invention. Appendix A attached also list other anchors which may be used, which are listed as illustrative only and not intended to be limiting as to the types of earth anchors that may used to practice versions of the invention. All anchors with suitable resistance to the desired climatic forces may be used. All components of the device and/or system are of sufficient strength to resist the desired climatic forces, i.e., wind speeds of 100 MPH, 120 MPH, 140 MPH or higher or any desired wind resistance strength. [0027] Now, an overall description of the method of making and using one version of the invention will be described in detail. In one embodiment, as depicted in FIG. 1 and FIG. 2 , at least one tension member, of sufficient strength to resist the desired climatic forces, further comprising a first tension member 10 (with a roof end 12 and an earth end 13 ) is attached to an attachment means 40 on an earth anchor means 41 (typically a mobile home screw-type anchor). The roof end 12 of the first tension member 10 is attached to the top tension member 14 over an eave cushion 20 disposed over the first roof eave 33 (with or without overhang) at the top of the bearing wall 32 which bears on the foundation 33 . The top tension member 14 then is looped over the roof surface 30 and perpendicular to the roof ridge 31 over a ridge cushion 21 and then to another eave cushion 20 on the second roof eave 34 (with or without overhang), attached to the second tension member 15 which is attached to the attachment means 40 on another earth anchor means 41 . [0028] An optional means for adjusting 11 (such as a ratchet, pulley, friction device, come-along, turnbuckle and/or other suitable adjusting/tensioning device) may be used to tighten the system after installation to the desired-tautness. The means for adjusting may also be a spring-biased locking knob (with or without a plurality of longitudinally disposed apertures on an elongated length-adjustable bar), belt-buckle (with or without a plurality of longitudinally disposed apertures on an elongated length-adjustable bar), snap, fastener, touch-fastener (Velcro), quick-release mechanism or any other means for adjusting, all well known in the art as of today. [0029] Alternately, the external tension member may be one continuous tension member 16 (as shown in FIG. 7 ) comprising the first tension member 10 , top tension member 14 and second tension member 15 and optional bottom tension member 17 all combined to comprise a single tension member, with or without a means for adjusting. [0030] To install and use one version of the invention on a structure, typically the operator would first install the two earth anchors 41 on opposite ends of the structure as shown in FIG. 1 and FIG. 2 . Then, for example as shown in FIG. 1 , the first end of an external continuous tension member 16 (comprising the first tension member 10 , top tension member 14 and second tension member 15 all combined, without the optional bottom tension member 17 in this example, to comprise a single tension member) is attached to the attachment means 40 on an earth anchor means 41 . The continuous tension member 16 is looped over the eaves ( 33 and 34 with or without overhang(s)) and roof ridge 31 and over the eave cushions 20 and ridge cushion 21 after first positioning the cushions in a preconfigured arrangement under the continuous tension member 16 , and then attached to the other earth anchor means 41 , also depicted in FIG. 1 and FIG. 2 . The at least one means for adjusting 11 (previously integrated into the continuous tension member 16 ) is tightened and the system is ready for use. [0031] To uninstall and remove this version of the invention from the structure, if desired, the above-referenced installation procedure is reversed. [0032] Another embodiment uses an external net anchored to at least one, a plurality or several earth anchor means as shown in FIG. 3 , for the external tension member. The size of the net openings may be of any size but should be scaled to cover the average size of a residential roof shingle when used on houses, as shown in FIG. 4 . For instance, the net opening could be sized to accommodate a typical residential roof shingle such as the standard 3-tab Sentinel Shingles manufactured by GAF Materials Corp. 1361 Alps Road, Wayne, N.J. 07470, (973)628-3000, which has an exposed surface of about 5 inches and about 13 inches wide. A net, for example, with openings of about 3 inches square would be sufficient for use in this application. Netting products such as those made by Global Net Service, Shengqun Zhou, 5-404 Nantong Road, Taizhou, Jiangsu Province, China 225300, Tel: 86-13901431072, Fax: 86-523-6666567, Email: [email protected] may be used in versions of this invention. Nets have the advantage of allowing the high wind force to penetrate the net's surface (as do pliable mesh membranes, which also may be used) while restraining the roof shingles underneath the external net or external pliable mesh membrane from separating from the sub-roof, well known in the art. [0033] These include fishing nets, fish nets, gillnets ropes, twines, cargo nets, construction and safety nets, sports nets, fishnets, hammocks, farming nets and ready to use nets which may be used in versions of the invention. Other types that may be used include: twisted knotted polyethylene & nylon nets, single strand, very strong and flexible and easily repaired, available in single or double knot; braided knotted nylon netting, which is more abrasion resistant than twisted netting, not quite as strong as twisted netting, more difficult to repair, more expensive, available in many colors and sizes (as are most nets); knotless nettings available in many sizes, lengths, and depths; monofilament nylon fishing net which is very similar to the twine commonly used in fishing reels, more abrasion resistant than multifilament netting, easily cleaned of debris, available in single, double knot, absorbs very little water (valuable in hurricane rains), available in many colors and sizes, all of which are listed as illustrative only and not intended to be limiting as to the types of nets or mesh pliable membranes that may used to practice versions of the invention. [0034] All types of tie downs (as they are commonly known in the industry), with or without a means for adjusting, may be used as the tension member(s), such as those available at www.Alibaba.com on the World Wide Web (WWW). These include ratchet tie downs, industrial safety belts, lashing strap belts, high-intensity polyester belts, web sling belts, polyester webbing slings, rigging hardware, wire rope, chains, synthetic fiber lifting slings, steel wire ropes and rigging, cargo lashings, bungee cords, tow ropes, luggage straps and buckles which are listed as illustrative only and not intended to be limiting as to the types of tie downs that may used to practice versions of the invention. [0035] The attachment means 40 for the external tension member tie downs to the earth anchors may be hooks, carabiners (such as those available at Rapid Response Gear at www.rapidresponse.com, (888) 600-9116, manufactured by Omega Pacific, the modified D'biner, built from certified, aircraft-quality aluminum-alloy bar stock with internally-threaded gate-lock locking mechanisms which mean that the even under load, the locking mechanisms can still be manipulated by hand and eliminates sticking gates, UL Classified, meets and exceeds NFPA 1983 L, ANSI/OSHA strength and construction requirements and standards), hand-tied knots, clamps, friction-type locks and other similar attachment hardware may be used, which are listed as illustrative only and not intended to be limiting as to the types of tie downs that may used to practice versions of the invention. [0036] To install and use another version of the invention on a structure, as shown in FIG. 3 and FIG. 4 , typically the operator would first install a plurality of earth anchors 41 around the perimeter of the structure in a preconfigured arrangement and locations. Then, for example, the first end of a plurality of external first tension members 10 , are attached to the attachment means 40 on a plurality earth anchor means 41 . The plurality of external tension members 10 are attached to a net means 15 (as shown in FIG. 4 ) which is spread over entire roof surface 30 , the eaves ( 33 and 34 with or without overhang(s)) and roof ridge 31 and over a plurality of eave cushions 20 and ridge cushions 21 (the cushions may be continuously disposed on the entire roof ridge 31 and roof eaves 33 and 34 , with or without overhang(s), as shown in FIG. 5 ) after first positioning the cushions in a preconfigured arrangement and locations under the external net means 15 , and then attached to the other plurality of earth anchor means 41 , also depicted in FIG. 3 , FIG. 4 and FIG. 5 . The at least one means for adjusting 11 (previously integrated into the plurality of tension members 10 ) is tightened sufficiently and the system is ready for use. Or, both tension members in combination with a net may be used as shown in FIG. 4 . Or, solely an external net may be used directly attached to the earth anchor means 41 via the attachment means 40 . [0037] To uninstall and remove this version of the invention from the structure, if desired, the above-referenced installation procedure is reversed. [0038] Another embodiment of the invention is depicted in FIG. 7 . This version is made and installed as previously described and may use at least one earth anchor 41 located upwind from the wind force and connected to an external continuous tension member 16 , using the optional bottom tension member 17 under the crawl space 35 . This version may also use an external net means 15 , with or without an external continuous tension member 16 , alone or in combination. A bottom edge protector 22 may also be used in this version as shown in FIG. 7 . [0039] The above-referenced device and system is not limited to the enumeration of parts or exact details of construction disclosed herein, as these are merely examples and not meant to be limiting. The shape, number and sizes of each external tension member, external net and/or net means, earth anchors, earth anchor means, attachment means and all other components may be varied so as to accommodate specific items and use thereof. The size, shape and materials of construction of the various components can be varied as desired. [0040] For example many buildings are designed using CAD (computer aided design) software programs, such as AutoCAD, available from Autodesk, Inc., 111 McInnis Parkway, San Rafael, Calif. 94903, USA, Phone: 415-507-5000, Fax: 415-507-5100. The CAD program can be combined with CAM (computer aided manufacturing) such as that available from BobCAD-CAM software, CADCAMDepot.com, 1981 Dunloe Circle, Dunedin, Fla. 34698. Toll Free Phone: 877-880-4488, International: 727-735-0584. [0041] The CAD-CAM software enables a 3 dimensional (3-D) building/structure roof design to be integrated into the manufacturing process of the roof net or mesh pliable membrane to be used. Thus, the roof net may be manufactured to the precise tolerances and shape of the roof. Thus CAD-CAM enables versions of the invention to be practiced on more complex roof structures that involve several ridges, valleys, eaves, etc. as needed by the operator. Nonlinear, round, curved and any other shape roofs may utilize versions of the invention. It is understood that these CAD-CAM techniques are well known to one skilled in the art and may be used to practice versions of the invention. [0042] Another embodiment of the invention may be used for aircraft hangars. This embodiment can be used for any aircraft hangar shape, but for illustrative purposes, FIG. 6 depicts an arch-shaped hangar 16 on a foundation 33 . In this application, this version of the device and system may comprise solely an external net 15 , with or without cushions, attached to a plurality of earth anchors, made and installed in a similar manner as the above-referenced roof eave and roof ridge type system. This embodiment may use external tension members and external netting or only use the external netting itself to restrain the structure and attached to the earth anchors. The attachment means 42 may be integrated into the existing concrete foundation 33 , as shown with the external tension member and/or external netting in dotted lines connected to an attachment means 42 in the foundation 33 (also referred to as a footer or footing in the industry). This attachment means could be an eye bolt, U bolt, bent rebar or similar hardware is either installed when the foundation concrete is poured in liquid form prior to hardening or installed after the foundation concrete has hardened by drilling and securing with epoxy glue, expandable anchors, “red eyes” and other type concrete anchors, all well known in the industry. [0043] The foregoing objects, benefits and advantages of versions of the invention are illustrative of those which can be addressed by versions of the invention and not intended to be limiting or exhaustive of the possible advantages that can be realized. These and other advantages will be apparent from the description herein or can be learned from practicing versions of the invention, both as embodied herein as examples or as modified in view of any variations which may be apparent to those of ordinary skill in the art. Therefore, the invention resides in the novel devices, methods, arrangements, systems, combinations and improvements herein shown and described as examples and not limited therein. [0044] It is also understood that whenever and/or is used in this patent application it means any combination or permutation of all, one, some, a plurality or none of each of the item or list mentioned, which is not intended to be limiting but merely for example and illustration. It is also understood that (s) designates either singular or plural. It is also understood that that “or” is an inclusive “or” to include all items in a list and not intended to be limiting and means any combination or permutation of all, one, some, a plurality or none of each of the item or list mentioned. It is also understood that “including” means “including but not limited to” any combination or permutation of all, one, some, a plurality or none of each of the item or list mentioned. [0045] As will be apparent to persons skilled in the art, such as an architect, engineer, designer, fabricator, net designer and other similar artisans skilled in the art, various modifications and adaptations of the structure and method of use above-described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the claims. Although the foregoing invention has been described in detail by way of illustration and example, it will be understood that the present invention is not limited to the particular description and specific embodiments described but may comprise any combination of the above elements and variations thereof, many of which will be obvious to those skilled in the art. Additionally, the acts and actions of fabricating, assembling, using, and maintaining the preferred embodiment of this invention is well known by those skilled in the art. Instead, the invention is limited and defined solely by the following claims. [0046] The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Appendix A 3 pages after this page, 16A, 16B and 16C [0047] [0000] Approved Tie Down Assemblies Number Manufacturer Product 1086 B-A EPCO Mobile Home Products EPCO Ground Hog Mobile Home Anchors 1308 S. Kalamazoo Avenue Models: RH61-6, RH-51-6, DRH51-6, DRH61-6 Marshall, MI 49068 1087 B-A Stromberg Carlson Products “Huggor” Mobile Home Tie Down PO Box 164 Models: 48/S, 48/D, T4-36S, T4-36D 226 E. 16th Street Traverse City, MI 49684 1088 B-A Transtationary Foundation Transtationary Foundation Systems Systems 20131 James Couzens Highway Detroit, MI 48235 1102 B-A Barker Manufacturing Company MH Pier/Tie Down Device 730 E. Michigan Avenue Models: MHAP-12, MHAP-13, MHAP-14, MHAP-15, and Battle Creek, MI 49016 MHAP-16 1107 B-A Imperial Stamping Co., Inc. MHA Corporation Home Anchors and Accessories 23852 Reedy Drive Models: MHA-SB-2, MHA-SB-3, MHA-SB-4, MHA-SB-6, MHA- Elkhart, IN 46514. SB-7, MHA-SB-8, MHA-MHA-SB-10, MHA-SB-12, MHA-SB-15- 36, MHA-SB-15-48, MHA-SB-16, MHA-SB-17, MHA-SB-20, MHA-SB-21, MHA-SB-22, MHA_SB-26, MHA-SB-46, MHA-SB, MHA-2, MHA-4, MHA-6, MHA-8, MHA-10, MHA-12, MHA-14, MHA-16, MHA-20, MHA-21, MHA-22, MHA-24, MHA-26, MHA- 33, MHA-39, MHA-40, MHA-56, and MHA-58 Doc. 92-071 1189 B-MH Anchor Sur Mobile Home Anchoring System Div. of Poly Foan Int'l. 1218 Lime Street PO Box 684 Fremont, OH 43420 1196 B-MH Barker Manufacturing Co. Stable Safe MH Tie Down 730 E. Michigan Avenue PO Box 460 Battle Creek, MI 49016 1198 B-MH American Skirting Co. The Crabline Tie Down Assembly 6560 Bethuy Road Anchorville, MI 48004 B-94-637 Tie Down Engineering, Inc. Mobile home anchors. 5901 Wheaton Drive Models: MI 2H, MI 2H6, MI 22, MRA, MRAX 48, and related Atlanta, GA 30336 accessories. PA-96-004 Home Pride, Inc. Mobile home anchors: 2976 Lee Highway, Unit 2 Models: HP-1, HP-3, HP-4, HP-10, HP-12, HP-13, HP-14, Bristol, VA 24201 HP-17, HP-30. Doc. 96-32 The anchoring system consists of steel disk anchors, steel concrete anchors, expansion bolts, strapping, and related accessories. PA-96-001 Minute Man Anchors, Inc. Manufactured housing tiedowns: 305 West King Street Models: 650-DH 5/8, 4636-DH 3/4, 36X-DH, THDH, East Flat Rock, NC 28726 650-DH 3/4, 4430-DH 5/8, 48X-DH, THDHLS, 650-DH 11/16, 4430-DH 11/16, 36-DH, FCI W/S, 636-DH 5/8, 4430-DH 3/4, 210-DH, FCII W/S, 636-DH 3/4, 4450-DH 5/8, 210-PDH, BUC W/S, 672-DH 3/4, 4450-DH 11/16, 210-JDH, SBNB, 860-DH 3/4, 4450-DH 3/4, 100-DH, MMASD2 MMA STRAP. Doc. 96-33 The anchoring system consists of earth auger anchors, strapping, cross drives, buckles, and related accessories. PA-94-001 Hydroflo Systems, Inc. Earth Anchor: 3729 Linden, S. E. Developed to stabilize the inward bow or deflection of Wyoming, MI 49548 masonry block or concrete walls caused by lateral earth pressure resulting from backfill against the wall. PA-97-001 GOP Industry Mobile Home Anchor: 19266 Berden Four-hole chain connector link used as an extension in their Harper Woods, MI 48225 patented Crab Line Tie Downs for mobile home installations. PA-99-001 Frenchy's Skirting, Inc. Manufactured Housing Tie-Down: 34111 Michigan Avenue Model: 031933 Wayne, MI 48184 Provides anchorage to withstand wind forces and uplift. PA-99-003 Tie Down Engineering Inc. Foundation/Anchoring System 5901 Wheaton Drive Model: Dirt System #59007 Atlanta, GA 30336 Concrete System #59008 Vector Dynamics - Doundation/Anchoring System Provides foundation/achoring system for manufactured housing and modular buildings to resist wind loads as designated by HUD Code (MHCSS 3280 306). 1474-BA Tie Down Engineering, Inc. ABS FOUNDATION PADS: 5901 Wheaton Drive Part #59300 - 2 sq. ft. Atlanta, GA 30336 Part #59301 - 2.5 sq. ft. (404) 344-0000 Part #59302 - 3 sq. ft. Submission PA-00-0001 BEAM CLAMPS: Part #59002 - Swivel Strap Connector Part #59003 - 3″ Swivel Strap Frame Connector (beam clamp) Part #59004 - 4″ Swvel Strap Frame Connector (beam clamp) Part #59005 - Adjustable Swivel Strap Frame Connector (clamp) Part #59011 - Flange Beam Clamp Part #59009 - Longitudinal Beam Clamp STABILIZER PLATE: Part #59291 1488-BA Benchmark Resources, Inc. Benchmark Insulated Concrete Wall System 70 S. Grey Road The Benchmark Insulated Concrete Wall System is an Auburn Hills, MI 48326 extruded polystyrene form with cold-formed stell channel and Submission PA-00-0002 steel bar reinforced concrete wall system to be used both below grade and above grade residential and light commercial applications. 1489-BA Tie Down Engineering, Inc. Vector Dynamics - Foundation/Anchoring System for 5901 Wheaton Drive manufactured housing and modular buildings to resist wind Atlanta, GA 30336 loads as designated by HUD Code (MHCSS 3280 306). (404) 344-0000 Amend Product Approval No. 1464-BA to add 18 inch round Submission PA-00-0003 foundation pier option. 1490-BA Tie Down Engineering, Inc. Part No. 59013 - Tube 5901 Wheaton Drive Part No. 59272 - Longitudinal Beam Clamp Atlanta, GA 30336 Part No. 59282 - Longitudinal Link (404) 344-0000 Part No. 59310 - Foundation Pad Submission PA-00- Part No. 59277 - Foundation Pad (Concrete) Part No. 59373 - Foundation Pad (Concrete)

An device, system and method of using is disclosed to provide a releasably attached external tension member(s), earth anchor(s), net(s), means for adjusting and means for attaching to the earth anchor(s) to accomplish an emergency structure restraint system.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION This invention relates to the treatment of wells penetrating subterranean formations and more particularly to the isolation of an interval within a well for the introduction of a treating fluid into an adjacent formation. BACKGROUND OF THE INVENTION Various treatment procedures are known in the art for the treatment of a well penetrating a subterranean formation. One common treatment procedure involves the hydraulic fracturing of a subterranean formation in order to increase the flow capacity thereof. Thus, in the oil industry, it is a conventional practice to hydraulically fracture a well in order to produce fractures or fissures in the surrounding formations and thus facilitate the flow of oil and/or gas into the well from the formation or the injection of fluids from the well into the formation. Such hydraulic fracturing can be accomplished by disposing a suitable fracturing fluid within the well opposite the formation to be fractured. The well is open to the formation by virtue of openings in a conduit, such as a casing string, or by virtue of an open completion in which a casing string is set to the top of the desired open interval and the formation face then exposed directly to the well below the shoe of the casing string. In any case, sufficient pressure is applied to the fracturing fluid and to the formation to cause the fluid to enter into the formation under a pressure sufficient to break down the formation with the formation of one or more fractures. Oftentimes the formation is ruptured to form vertical fractures. Particularly, in relatively deep formations, the fractures are naturally oriented in a predominantly vertical direction. One or more fractures may be produced in the course of a fracturing operation, or the same well may be fractured several times at different intervals in the same or different formation. Another widely used treating technique involves acidizing, which is generally applied to calcareous formations such as limestone. In acidizing, an acidizing fluid such as hydrochloric acid is introduced into the well and into the interval of the formation to be treated which is exposed in the well. Acidizing may be carried out as so-called “matrix acidizing” procedures or as “acid fracturing” procedures. In acid fracturing, the acidizing fluid is injected into the well under a sufficient pressure to fracture the formation in the manner described previously. An increase in permeability in the formation adjacent the well is produced by the fractures formed in the formation as well as by the chemical reaction of the acid with the formation material. In matrix acidizing, the acidizing fluid is introduced through the well into the formation at a pressure below the breakdown pressure of the formation. In this case, the primary action is an increase in permeability primarily by the chemical reaction of the acid within the formation with there being little or no effect of a mechanical disruption of the formation, such as occurs in hydraulic fracturing. Various other treatment techniques are available for increasing the permeability of a formation adjacent a well or otherwise imparting a desired characteristic to the formation. For example, solvents can sometimes be involved as a treating fluid in order to remove unwanted material from the formation in the vicinity of the well bore. SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a method for the treatment of a subterranean formation penetrated by a well. In carrying out the invention, first and second flow paths are established within the well, extending from the wellhead into the vicinity of the subterranean formation. A plugging fluid comprising a suspension of a particulate plugging agent in a carrier liquid is circulated into the first of the flow paths and into the well in contact with the wall of the well within the subterranean formation. The carrier liquid is separated from the particulate plugging agent by circulating the carrier liquid into a second flow path. Circulation of the liquid is accomplished through a set of openings leading to the second flow path, which are dimensioned to allow the passage of the carrier liquid while retaining the particulate plugging agent in contact with the set of openings. The circulation of the plugging fluid continues until the particulate plugging agent accumulates to form a bridge packing within the well. The bridge packing acts similarly as a mechanical packer to form a barrier within the well. Subsequent to establishing the bridge packing, a treating fluid is introduced into the well through the first flow path and in contact with the surface of the formation in the well adjacent to the accumulated plugging agent forming the bridge packing. In a further aspect of the invention, a treatment procedure is carried out in a section of a well penetrating a subterranean formation and having a return tubing string provided with spaced screened sections at a location in the well adjacent the subterranean formation. A working tubing string opens into the interior of the well intermediate the spaced screen sections. In carrying out the invention, a plugging agent comprising a suspension of particulate plugging agent in a carrier liquid is circulated through the working string into the intermediate interval between the screen sections. The carrier liquid is flowed through openings in the spaced screen section, which are sized to allow the passage of the carrier liquid while retaining the particulate plugging agent in the well in contact with the screen sections. The flow of the plugging agent within the well is continued until the particulate plugging agent in the fluid accumulates in the well adjacent the screen sections to form spaced bridge packings within the well and surrounding the return string. Thereafter, a treating fluid is introduced into the well and into the interval of the well intermediate the spaced bridge packings and introduced into the formation. In a specific application of the invention, the treating fluid is a fracturing fluid introduced into the treating interval under pressure sufficient to hydraulically fracture the formation. In another embodiment of the invention, the treating fluid is an acidizing fluid effective to acidize the formation in either a matrix acidizing or acid fracturing operation. Preferably, subsequent to the introduction of the treating fluid into the well, a clean-up fluid is circulated down the well into the return tubing string to displace the accumulated particulate plugging agent away from the screened sections and disrupt and remove the bridge packings. In carrying out the hydraulic fracturing operations, the fracturing fluid is normally in the nature of a cross-linked gel having a high viscosity. The clean-up fluid can incorporate a breaker to break down the viscosifying agent in the fracturing fluid. For example, where the viscosifier in an aqueous-based fracturing agent takes the form of hydroxethylcellulose, the clean-up fluid can incorporate an acid such as hydrochloric acid, which functions to break the fracturing fluid gel to a liquid of much lower viscosity. Subsequently, the tubing strings can be moved longitudinally through the well to a second location within the well bore spaced from the originally treated location and the operation then repeated to treat a different section of the well bore. The tubing strings employed in carrying out the invention may be parallel tubing strings or they may be concentrically oriented tubing strings in which the working string disposed within the return string provides a return pathway formed by the annulus of the working string and the return string. In a further application of the invention, a treating process is carried out in a well section that extends in a horizontal orientation within the subterranean formation. The fracturing operation is carried out to hydraulically fracture the formation and form a vertically oriented fracture within the formation extending from the horizontally oriented well bore. Thereafter, the return and working strings are moved longitudinally through the horizontally extending well section to a second location, and the operation is repeated to form a second set of bridge packings followed by hydraulic fracturing to form a second vertically oriented fracture within the well section spaced at some distance from the initially formed vertically oriented fracture. These operations can be repeated as many times as desired in order to produce multiple fractures. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic illustration of a well with parts broken away, showing the formation of spaced bridge packings using concentrically oriented tubing strings. FIG. 2 is a schematic illustration of a well with parts broken away showing the invention as carried out employing parallel tubing strings. FIG. 3 is a schematic illustration of a section of a well showing a preferred form of screen section in a parallel string configuration. FIG. 4 is a schematic illustration of a well with parts broken away showing the application of the invention in a deviated well having a horizontal well section within a subterranean formation. FIGS. 5 and 6 are schematic illustrations with parts broken away of a horizontal well section showing sequential operations within the well section. FIG. 7 is a schematic illustration of a well with parts broken away showing the application of the invention in forming a single bridge packing with a concentric tubing string assembly. FIG. 8 is a schematic illustration of a well with parts broken away showing the application of the invention in forming a single bridge packing with parallel tubing string configuration. FIG. 9 is a side elevation with parts broken away showing a downhole well assembly suitable for use in carrying out the present invention. FIG. 10 is a side elevation with parts broken away showing another form of a downhole well assembly suitable for use in carrying out the present invention. FIG. 11 is a side elevation of a tubing section employed in a preferred screen section for use in the present invention. DETAILED DESCRIPTION OF THE INVENTION The present invention provides for the formation of one or more downhole bridge packings which can be placed at precise locations in a well by fluid circulation techniques in order to permit well-defined access to a formation by a suitable treating agent. The bridge packings can be assembled within the well without the use of special downhole mechanical packings and can be readily removed after the treatment procedure by a reverse circulation technique. The bridge packings are formed by the circulation downhole of a particulate plugging agent which is suspended in a suitable carrier liquid. The plugging fluid is circulated through a downhole screen at a desired location which permits the suspending liquid to readily flow through the screen openings but retards passage of the particulate plugging agent so that it accumulates in the well at the desired downhole location. The plugging agent may take the form of gravel or a gravel/sand mixture as described in greater detail below. Other suitable mixtures of porous permeable materials may be employed. The gravel-plugging agent is suspended within a liquid that may be either oil- or water-based for circulation down the well to the desired downhole location. The carrier liquid typically is treated with a thickening agent in order to provide a viscosity, normally within the range of 10-1,000 centipoises, preferably within the range of 30-200 centipoises, which is effective to retain the plugging agent in suspension as the plugging fluid is circulated through the well. However liquids of low viscosity, for example, water having a viscosity of about 1 cp can be used with low density plugging agents. The invention may be carried out employing tubing sections suspended down hole from a mechanical packer, which may be equipped with a crossover tool, or it may be carried out employing tubing strings which extend from the wellhead to the downhole location of the well being treated. The invention will be described initially with respect to the latter arrangement, which normally will be employed only in relatively shallow wells, in order to illustrate in a simple manner the flow of fluids in the course of carrying out the invention. Turning now to the drawings and referring first to FIG. 1, there is illustrated a well 10 , which extends from the earth's surface 12 into a subterranean formation 14 . Formation 14 may be of any suitable geologic structure and normally will be productive of oil and/or gas. The well 10 is provided with a casing string 15 which extends from the surface of the earth to the top of formation 14 . Typically, casing string 15 will be cemented within the well to provide a cement sheath (not shown) between the outer surface of the casing and the wall of the well. It is to be recognized that the well structure of FIG. 1 is highly schematic. While only a single casing string is shown, as a practical matter a plurality of casing strings can be and usually will be employed in completing the well. Also, while FIG. 1 depicts a so-called “open hole” completion, the well may be set with casing and cemented through the formation 14 and the casing then perforated to provide a production interval open to the well. The well is completed with concentrically run tubing strings comprising an outer tubing 17 and an inner tubing string 18 . The tubing strings 17 and 18 are hung in the well from the surface by suitable wellhead support structure (not shown). A flow line equipped with a valve 20 extends from the tubing 18 to allow for the introduction and withdrawal of fluids. A similar flow line with valve 21 extends from tubing string 17 and allows for the introduction and withdrawal of fluids through the annulus 22 , defined by the tubing strings 17 and 18 . The casing string is provided with a flow line and valve 23 providing access to the tubing-casing annulus. The tubing strings 17 and 18 are both closed at the bottom by closure plugs 17 a and 18 a . The tubing string 17 is provided with spaced screen sections 24 and 25 . The screen sections may be of any suitable type as long as they provide for openings sufficient to permit the egress and ingress of the liquid carrier while blocking passage of all or at least a substantial portion of the particulate plugging agent. In a typical downhole configuration involving a 4-inch diameter tubing set within a well bore having a nominal diameter of about 8-9 inches, the screen sections may be formulated by grid screens having sieve openings within the range of about 0.006-0.01 inch, corresponding generally to a standard sieves of 60-100 mesh. Other configurations can be used. For example, the screen sections can be provided by perforated sections of tubing or tubing which has been slotted vertically or vertically and horizontally, providing openings sufficient to block the passage of plugging agent. Also, sintered metal screens can be employed. The screen sections may be of any suitable dimension. In a well configuration as described above, the screen sections 24 and 25 may each be about 2-30 feet in length with an interval between the screen sections (from the top of the lower section to the bottom of the upper section) of about 5-30 feet. The downhole well assembly is provided with one or more flow ports such as provided by a spider assembly 28 comprised of a plurality of tubes extending from the interior of tubing string 18 to the exterior of tubing string 17 to permit the flow of fluid between the interior of tubing string 18 and the exterior of tubing string 17 . In carrying out the invention, the slurry of particulate plugging agent in the carrier liquid is circulated through line 20 and down the well through tubing 18 . The slurry flows through the downhole spider assembly 28 into the annular space 30 between the wall of the well and the outer surface of tubing 17 . Within the well annulus 30 , the slurry flows through the screens 24 and 25 into the annulus 22 defined by tubing strings 17 and 18 . If desired, a packer (not shown) may be set in the well annulus above screen 24 in order to direct the flow of fluid into the annulus 22 rather than up the well annulus 30 . However, this often will be unnecessary. The plugging fluid flowing down the well (having a suspension of gravel or the like in the carrier liquid) will have a higher bulk density than the carrier liquid itself. Thus, as the carrier liquid flows through the screens 24 and 25 causing the granular plugging agent to accumulate in the vicinity of the screens, the pressure gradient across the screens will be less than the pressure gradient up the well. Thus, flow will be predominantly through the screen and into the tubing annulus 22 . At the conclusion of the preliminary circulation step, effective bridge packings 32 and 34 are formed adjacent the screens 24 and 25 . The packings are retained in place by the hydrostatic pressure in the well annulus 30 , and the packings are sufficiently impermeable to prevent any significant migration of fluid from one side of a packing to the other. At the conclusion of the formation of the bridging plugs, a suitable treating fluid is injected via line 20 into tubing 18 and through the spider assembly 28 into the space between the bridge packings 32 and 34 . By way of example, a fracturing fluid may be injected down tubing 18 and under pressure sufficient to form a fracture 36 in the formation 14 . Alternatively, the treating procedure may take the form of an acidizing procedure or an acid fracturing procedure. Standard procedures can be employed in carrying out the treating operation. Where a fracturing operation is involved, initial spearhead fluid will be injected in accordance with accepted practice under a sufficient pressure to exceed the breakdown pressure of the formation and fracture the formation. Normally the spearhead fluid will be a viscous fluid, typically having a viscosity within the range of 10-1,000 centipoises which is free of propping agent or has a very low propping agent concentration. In order to insure that the bridge packings remain in place during the initial fracturing procedure, the spearhead fluid can incorporate a bridging agent such as sand employed in relatively low concentration, typically within the range of 1-50 pounds per barrel. After fracturing is initiated in the formation, a fracturing fluid carrying a propping agent, is pumped down tubing 18 to propagate the fracture in the formation and leave it packed with propping agent. Typically a “sand out” condition will occur, as indicated by an increase in pressure, and the fracturing operation is then concluded. At the conclusion of the treating procedure, the bridge packings may be removed. In order to remove the bridge packings 32 and 34 , a reverse circulating fluid, which may be the same or different from the fluid employed as the carrier liquid initially, is injected through valve 21 into the tubing annulus 22 . This creates a reverse pressure differential through the screen sections 24 and 25 causes the bridge packings to begin to disintegrate. Ultimately, the bridge packings are removed by the particulate plugging agent becoming suspended in carrier liquid and carried away from the vicinity of the formation. Normally, the particulate plugging agent will be reverse circulated up tubing string 18 to the surface and removed from the well. The suspension of particulate plugging in the carrier liquid can be circulated up the annulus 30 . The reverse circulation fluid may be different from the fluid employed as the initial carrier liquid. The reverse circulation fluid may take the form initially of a lower viscosity fluid to facilitate the initial removal of the particulate plugging agent. Where the carrier liquid incorporates a cross linked gel, the reverse circulation flow may contain a breaking agent to help remove the cross-linked gel from the bridge packing. Suitable gelling agents include guar gum or hydroxyethylcellulose. They may be used in any suitable amounts. Typically, they are used in minimum amounts of about 20-25 to perhaps 30 lbs. per thousand gallons. The gel may be broken through the use of oxydizers or enzymes to effect suitable decomposition reactions. Typically, oxydizers are used. Suitable oxidizers include sodium hypochlorite and ammonium persulfate. Turning now to FIG. 2, there is illustrated an alternative well structure for use in carrying out the present invention in which parallel tubing strings are employed. In FIG. 2 like elements are designated by the same reference numerals as shown in FIG. 1 and the foregoing description is applicable to FIG. 2 with the exception of the modification involving the use of parallel tubing strings. In FIG. 2, string 38 (analogous in function to tubing string 18 ) and tubing string 40 (analogous in function to tubing string 17 ) are run in a parallel configuration. The tubing strings are dimensioned to take into account the parallel configuration. By way of example, in a well having a nominal diameter of 8-9 inches, each of strings 38 and 40 may be 2-3-inch tubing strings. Tubing string 40 is provided with screen sections 41 and 42 , which may be configured with respect to the size of the openings, similarly as described above with respect to FIG. 1 . Tubing string 40 is closed at its lower end with a suitable plug indicated by reference numeral 40 a . Tubing string 38 is provided with a closure or seal 44 at its bottom end and is provided with a perforated section 45 to allow for the flow of fluid from tubing 38 into the well bore. Alternatively, instead of providing tubing string 38 with a perforated section, the tubing string may be open at its bottom end to provide for flow of fluids from the interior of the tubing string into the well. In this case the lower end of the tubing sting should be located approximately midway between the locations of the screen sections 41 and 42 . The operation of the invention employing the parallel tubing configuration shown in FIG. 2 is similar to the operation employing the concentric tubing strings as shown in FIG. 1. A plugging fluid comprising a suspension of particulate plugging agent is circulated down the well via tubing 38 . The openings in the perforated section 45 of tubing 38 are sufficient to permit the passage of the particulate plugging agent in suspension in the carrier liquid without the plugging agent screening out of suspension and accumulating in the interior of the tubing string 38 . The plugging fluid is circulated down tubing 38 into the well and through the screen sections 41 and 42 in order to form bridge packings 47 and 48 . As the carrier liquid passes through the screen sections and into tubing string 40 , the bridge packings 47 and 48 are formed similarly as described above. At the conclusion of formation of the bridge packings, the treating fluid is then injected down tubing string 38 and into the interval of the well between bridge packings 47 and 48 to carry out the desired treating operation. At the conclusion of the treating operation, the bridge packings 47 and 48 may be removed by circulation of the viscous carrier liquid down the well in tubing string 40 . Alternatively, a different fluid may be used as described previously. In carrying out the invention with the parallel tubing configuration of FIG. 2, the lower bridge packing 47 will occupy a substantially greater cross-sectional area of the well bore than in the case of employing concentric tubing strings. In a preferred embodiment of the invention, in order to facilitate removal of the lower screen section in conjunction with dispersion of the bridge packing, the lower screen section can be formed in a tapered configuration. This embodiment of the invention is shown in FIG. 3, in which the tubing 40 is shown to terminate in a tapered screen section 49 . By way of example, where the tubing string 40 is a 3-inch tubing, the screen section may taper downwardly to provide a lower dimension indicated by reference numeral 50 of about half of the dimension of the tubing string. A preferred application of the present invention is in carrying out multiple treatments in a single wellbore. This is facilitated by the fact that the bridge packings can be readily removed by a reverse circulation technique, the tubing assembly then moved to a new location in the well, and a new set of bridge packings put in place. This mode of operation is particularly advantageous in the operation of wells in which the producing section is slanted substantially from the vertical in some cases to a nominally horizontal orientation. Such horizontal well bores are typically employed in relatively thick gas or oil formations where the slant well follows generally the dip of the formation and especially where the formation permeability is relatively low. Such slant wells or horizontal wells can be formed by any suitable technique. One technique involves the drilling of a vertical well followed by the use of whipstocks to progressively deviate from the vertical in a direction to arrive at the horizontal orientation. Such horizontal wells may also be formed using coiled tubing equipment of the type disclosed, for example, in U.S. Pat. No. 5,215,151 to Smith et al. Turning now to FIG. 4, there is illustrated a well 52 which has been deviated from the vertical into a horizontal configuration to generally follow the dip of subterranean formation 54 . The well is equipped with a concentric tubing arrangement having inner and outer tubing strings 56 and 57 corresponding generally to the tubing strings 17 and 18 of FIG. 1 . The outer tubing string 57 is equipped with upper and lower screen sections 58 and 59 , which are disposed above and below a spider assembly 60 providing for the flow of fluid between the interior of tubing string 56 and the exterior of tubing string 57 . In operation of the system of FIG. 4, the suspension of a particulate plugging agent is circulated down tubing string 56 and through spider assembly 60 into the annulus 62 between the wall of the well 52 and the outer tubing string 57 . The carrier liquid flows through the screen elements 58 and 59 and into the tubing annulus 64 , resulting in the formulation of bridge packings similarly as described above. A tubing fracturing operation is then initiated in order to form one or more vertical fractures as indicated by reference character 65 . In the stimulation of formations penetrated by horizontal or deviated wells as shown in FIG. 4, it is sometimes desirable to form a series of spaced vertical fractures. This sequence of operation is shown by FIGS. 5 and 6. FIG. 5 illustrates the location of the tubing strings 56 and 57 at a second location moved uphole from the initial location where fracture 65 was formed. The circulation procedure is repeated to again provide spaced bridge packings 67 and 68 followed by a fracturing operation in order to form a second fracture system 70 spaced horizontally from the first fracture system 65 . Thereafter, circulation is reversed as indicated in FIG. 6 with a carrier liquid (without particulate plugging agents) circulated down the annulus 64 to disrupt the bridge packings with return of fluid up the inner tubing string 56 and, if desired, also within the well-tubing annulus 62 . If desired, the process can be repeated by again moving the tubing assembly uphole and forming new bridge packings at yet another location followed by fracturing to produce a third vertical fracture system spaced from the systems 65 and 70 . Usually in carrying out the invention in deviated wells as depicted in FIGS. 4 through 6, it will be preferred to employ a concentric tubing arrangement rather than a parallel tubing arrangement configuration of the type depicted in FIG. 2 . When using the concentric tubing arrangement, suitable centralizers can be employed along the length of the concentric tubing strings in order to maintain the generally annular spacing shown. A further embodiment of the invention, as carried out employing only a single bridge packing, is shown in FIG. 7 . In the system of FIG. 7, a concentric tubing arrangement similar to that shown in FIG. 1 is employed with the exception that the interior tubing string 72 extends through the bottom of the exterior tubing string 74 . The exterior tubing string is provided with a suitable closure element 79 in order to seal the annulus 76 between the inner and outer tubing strings at the bottom. In this embodiment of the invention, normally carried out near the bottom of a well, the dispersion of plugging agent in the carrier liquid is circulated down tubing string 72 and into the well bore. The carrier liquid is returned from the well bore through string screen 77 into the tubing annulus 76 to form a bridge packing 78 similarly as described previously. Once the packing is formed, a suitable treating operation can be carried out by the injection of a treating fluid such as a fracturing fluid or an acidizing fluid down the interior tubing string 72 into the well section below the bridge packing 78 . At the conclusion of the treating operation, flow can be reversed by circulating the carrier liquid down the tubing annulus 76 to displace the accumulation of particulate plugging agent away from the screen section 77 . FIG. 8 illustrates a parallel tubing string configuration employed to provide a single bridge packing. Here, tubing string 80 is open at the bottom, and tubing string 82 is provided with a closure 83 and a screen section 84 spaced upwardly from the lower end of the tubing string. A carrier liquid containing a particulate plugging agent in suspension is circulated down tubing string 80 through the screen section and up tubing string 82 in order to form a bridge packing 86 . The treating operation can be carried out through tubing string 80 , and at the conclusion of the treating operation, reverse circulation down tubing 82 is instituted to disrupt the bridge packing 86 , similarly as described above. The invention as thus far described involves the use of separate tubing strings run in parallel or concentrical configuration from the wellhead to the vicinity of the formation undergoing treatment. While applications of this nature are useful, particularly in relatively shallow wells, the tubing arrangements involved become relatively cumbersome when the invention is carried out in wells of substantial depth, particularly where the depth of the well to the formation undergoing treatment exceeds about 1,000-2,000 ft. In such cases it will usually be desirable to run a well tool providing separate flow paths as described above on a single tubing string equipped with a packer. If desired, the packer may be equipped with a flow control tool of conventional configuration to permit different flow paths from the surface of the well to the downhole location through a single tubing string and/or through the tubing-casing annulus. Turning to FIG. 9, there is illustrated a well 10 having a single tubing string 90 extending from the surface of the well (not shown). Supported on the tubing string 90 is a mechanical packer 91 which supports sections of tubings 92 and 93 . Tubing section 93 is equipped with upper and lower screen sections 94 and 95 and is analogous in operation to the tubing string 40 described above with reference to FIG. 2 . Tubing string 92 is provided with a perforated section 96 and is analogous in operation to the tubing string 38 described above with reference to FIG. 2 . The tubing sections 92 and 93 are secured to one another in a fixed space location by the packer 91 and by means of spacing elements 97 extending between the tubing sections. Spacing elements 97 do not, of course, provide fluid passages between the tubing sections. Tubing 92 can be placed in fluid communication with the tubing string 90 through a passageway 99 in the packer, and the interior of tubing string 93 placed in fluid communication with the tubing-casing annulus 98 by means of passageway indicated by broken lines 100 . In operation of the well tool shown in FIG. 9, a suspension of the particulate plugging agent in a suitable carrier liquid is circulated down the well via tubing 90 and exits into the well bore via perforations 96 . The carrier liquid is circulated through screen sections 94 and 95 , which are configured as described previously, to permit the passage of the carrier liquid but retain the particulate plugging agent on the screen sections to form bridge packings (not shown) similarly as described above. Return flow in the configuration shown is through the tubing-casing annulus 98 . The lower screen section 95 is tapered as described previously in order to facilitate removal of the well tool. At the conclusion of the treating operation carried out through tubings 90 and 92 , carrier liquid may be circulated down the tubing casing annulus 98 into tubing section 93 . At the same time, the packer 97 may be released, and upward strain imposed by the working tubing 90 with the tapered screen section 95 facilitating removal from the lower bridge packing as described previously. FIG. 10 is a side elevation with parts broken away of a downhole tool incorporating concentric tubing sections, which function similarly as described above with reference to FIG. 1 . In FIG. 10, like elements as are shown in FIG. 9 are designated by the same reference numerals as used in FIG. 9 . In the tool of FIG. 10, an outer concentric tubing 101 is provided with upper and lower screen sections 102 and 103 . Also suspended from the packer 91 is a concentric inner tubing section 105 , which is provided with an upper spider section 106 and a lower spider section (not shown) terminating in perforations in the outer tubing section 101 indicated by reference numeral 108 . The spider sections provide flow passages from the interior of tubing section 105 to the exterior of the tubing string 101 . The annulus 109 between the inner and outer tubing strings is placed in fluid communication with the tubing-casing annulus 98 through a passageway 110 in the packer 91 as indicated by broken lines. The interior of the tubing string 105 is placed in fluid communication with the working tubing string 90 as indicated by the broken line passageway 112 . The operation of the well tool shown in FIG. 10 is similar as that described above with reference to FIG. 1 . The carrier liquid containing the particulate plugging agent is introduced into the well through tubing 90 into tubing section 105 and thence outwardly through the spider passageways to the exterior of outer tubing section 101 . Return flow is directed into annulus 109 and then upwardly through the tubing-casing annulus 98 to form bridge packings (not shown) adjacent screen sections 102 and 103 . As disclosed previously, the screen sections employed in the present invention may be of any suitable type but normally will take the form of a 0.006-0.01 inch mesh screen. FIG. 11 shows a suitable screen section configuration in which the screen section of the tubing 114 is provided with perforations 116 . A wire mesh screen (not shown) is wrapped around the perforated section of pipe 114 . The pipe functions to support the screen element. In addition, by appropriately sizing the perforations 116 when the reverse circulation carrier liquid is pumped down the well flow and flow through the constricted perforations 111 , it exits at a relatively high velocity, thus facilitating disruption of the particulate bridging agent around the screen section. As described previously, the present invention may be carried out employing treating fluids other than those commonly used in acidizing, fracturing, or acid fracturing operations. A treating fluid may take the form of a solvent, other than an acidizing fluid, in order to remove material immediately adjacent the well bore to facilitate fluid flow between the well bore and the formation. Alternatively, a treating agent in the nature of a plugging agent can be introduced into the well in order to seal a section of the formation intermediate the bridge packings formed adjacent the screen sections. For example, a suspension of a thermoset polymer may be introduced into the well, followed by the introduction of a setting agent to crosslink the polymer and form a seal within a limited portion of the well bore. Suitable materials useful in the embodiment of this nature include crosslinked hydroxyethylcellulose. The screen sections employed in the various embodiments of the invention may, as noted previously, be relatively short, e.g., on the order of about one or two feet. However, as a practical matter, screen sections will usually be provided ranging in lengths from about 5 to 20 feet. The interval between screen sections may range from a low as 2 feet up to perhaps 60 feet in length, depending upon the formation interval to be treated. However, a typical spacing between the screen sections will be about 10-30 feet from the top of the lower screen section to the bottom of the upper screen section. From the foregoing description, it will be recognized that the viscosity of the carrier liquid and the particle size range and density of the particulate plugging agent are interrelated. In addition, the size of the screen openings is related to the characteristic of the particulate plugging agent since all or most of the plugging agent should be retained on the screen to form the bridge packing. The particulate plugging agent preferably will take the form of a sand/gravel mixture having a specific gravity of about 1.5-3.5 with a particle size distribution which promotes packing of the relatively fine sand particles within the interstices formed by the somewhat coarser gravel particles. For example, a suitable particulate plugging agent may comprise about 40-60 wt. % gravel having a particle size distribution of about 20-40 mesh and a relatively fine 40-60 mesh size sand portion comprising about 40-60 wt. % of the mixture. For such a particulate plugging agent, the viscosity of the carrier liquid should be within the range of about 20-200 centipoises. The screen section may take the form of a 0.006-0.01 inch mesh screen. Where the screen is wrapped around underlying perforated pipe as shown in FIG. 11, the perforations may have a diameter of about ⅛-⅜ inches with about 2-50 perforations per foot of pipe. Having described specific embodiments of the present invention, it will be understood that modifications thereof may be suggested to those skilled in the art, and it is intended to cover all such modifications as fall within the scope of the appended claims.

A method for the treatment of a subterranean formation penetrated by a well in which, first and second flow paths are established from the wellhead into the vicinity of the formation. A plugging fluid comprising a suspension of a particulate plugging agent in a carrier liquid is circulated into the first flow path and into contact with the wall of the well within the subterranean formation. The carrier liquid is separated from the particulate plugging agent by circulating the carrier liquid through a set of openings leading to the second flow path, which are dimensioned to allow the passage of the carrier liquid while retaining the particulate plugging agent in contact with the set of openings. The circulation of the plugging fluid continues until the particulate plugging agent accumulates to form a bridge packing within the well. Subsequent to establishing the bridge packing, a treating fluid is introduced into the well through the first flow path and in contact with the surface of the formation in the well adjacent to the bridge packing. The treating fluid may be a fracturing fluid under or an acidizing fluid. A clean-up fluid is circulated into the second flow path to remove the bridge packing.

You are an expert at summarizing long articles. Proceed to summarize the following text: TECHNICAL FIELD This invention relates to the field of excavating work machines, and, more particularly, to a system for modulating a boom assembly for linear excavation. BACKGROUND Work machines that have boom assemblies serve a variety of functions, such as digging ditches, grading surfaces, and laying pipe. In order to carry out these functions, it is advantageous for the boom assembly to extend and retracted in such a manner that the work implement is kept on a linear path during the function. An operator controls the movement of the boom assembly by moving control levers or joysticks. Hydraulic actuators, connected to the boom assembly, receive the operator commands and move the boom assembly accordingly. When grading a surface, the operator extends the boom assembly out and places the tip of the work implement into the material at an appropriate depth and angle. In order to create the linear surface, the operator must raise the boom and draw the stick in at a coordinated rate, such that the work implement follows a linear path. This takes high operator skill to coordinate the movement of the boom and stick and remove the appropriate amount of material. Some manufacturers have tried to anticipate such a scenario and have means to coordinate the movement of the boom assembly. One known control device is found in U.S. Pat. No. 4,332,517, issued to Michiaki Igarashi et al. on Jun. 1, 1982. Igarashi discloses a control device whereupon one cylinder is manually controlled and the operation of the remaining cylinders are calculated using angle detectors provided on the boom, bucket, and arm cylinders. The present invention is directed to overcoming one or more of the problems set forth above. SUMMARY OF THE INVENTION A method of modulating a boom assembly to perform in a linear manner is disclosed. The boom assembly includes a boom and a stick. The method comprising the steps of sending at least one lever signal to a control device indicative of operator desired direction and desired velocity of the boom and the stick, calibrating the lever signals to provide a boom command signal and a stick command signal, applying an algorithm to the boom command signal and the stick command signal, which the algorithm uses command signal mapping, and providing a modulating factor to the control device as a result of the algorithm. A method of using a work machine to grade a surface is disclosed. The work machine having a boom, a stick, and a work implement coupled to the stick, each of the boom and stick is controllable by at least one lever. The method includes the steps of activating at least one lever to produce a command signal comprising at least one of a stick command signal and a boom command signal, communicating the command signal to a control device, and using the control device to modulate the command signal in accordance with a command signal mapping such that said work implement travels in a linear path. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a drawing of an embodiment of a work machine; FIG. 2 is a diagrammatic view of an embodiment of an algorithm. DETAILED DESCRIPTION FIG. 1 depicts a work machine 100 being attached with a boom assembly 102 . The boom assembly 102 comprises a boom 104 pivotally connected to a boom support bracket 106 of the work machine 100 , a stick 108 pivotally connected to the boom 104 , and a work implement 110 pivotally connected to the stick 108 . A boom actuator 112 , such as a hydraulic cylinder, having one end connected to the boom 104 and the other end connected to the boom support bracket 106 , rotates the boom 104 relative to the work machine 100 about a horizontal axis. A stick actuator 114 , such as a hydraulic cylinder, having one end connected to the boom 104 and the other end connected to the stick 108 , rotates the stick 108 relative to the boom 104 about a horizontal axis. A work implement actuator 116 , such as a hydraulic cylinder, having one end connected to the stick 108 and the other end connected to the work implement 110 , rotates the work implement 110 relative to the stick 108 about a horizontal axis. An operator's cab 118 , being positioned to view the boom assembly 102 , includes a plurality of levers 120 for commanding the boom 104 , stick 108 , and work implement 110 . The plurality of levers 120 are connected to a control device 122 within the work machine 100 . The control device 122 , such as a programmable electronic control module (ECM), is capable of sending command signals to control the respective boom, stick, and work implement actuators 112 , 114 , and 116 , upon operator commands. The plurality of levers 120 are operator controlled and capable of sending lever signals to the control device 122 , indicative of the position of the plurality of levers 120 . The control device 122 applies a pre-determined calibration factor to the lever signal and converts the lever signal to a command signal. For exemplary purposes, the calibrated command signals for the boom 104 , stick 108 , and work implement 110 would have a range of −1000 to +1000, respectively, depending on the operator desired direction and desired velocity of the rotating boom 104 , stick 108 , and work implement 110 . The −1000 would represent a full command signal to rotating in one of the clockwise or counter-clockwise direction. The +1000 would represent a full command signal to rotate in the opposing direction of the −1000. If the plurality of levers 120 is in the neutral position, 0 would represent the command signal. In FIG. 2 , the control device 122 executes an algorithm in a continual manner capable of providing a modulating factor 201 to the command signal for controlling the boom 104 , as a result of command signal mapping. For example, an operator gives full commands for the boom 104 and stick 108 represented by calibrated command signals of −1000 for the boom and −1000 for the stick. The algorithm maps the command signals for the boom 104 and stick 108 and provides the modulating factor 201 that changes the command signal to the boom to −500. The details of the algorithm and calculations are disclosed hereinafter. A boom map 202 receives a boom command signal 203 from the control device 122 , indicative of the lever signal from the plurality of levers 120 . The boom map 202 provides a boom map output constant 205 that is indicative of the boom command signal 203 . For exemplary purposes, the boom map 202 includes a pre-defined map 204 on an X and Y axis. The X axis represents the boom command signal 203 , with a scale of −1000 to +1000, indicative of the maximum and minimum values of the boom command signal 203 , and the Y axis represents the boom map output constant 205 with a scale of 0 to 1, indicative of the maximum and minimum boom map output constant 205 values. The boom command signal 203 of less than 0 would provide the boom map output constant 205 of 1, and the boom command signal 203 equal to or greater than 0 would provide the boom map output constant 205 of 0. A subtraction factor map 206 receives a calculated signal 208 that is indicative of calculating the boom and stick command signals 203 , 209 from the control device 122 . The subtraction factor map 206 provides a subtraction factor map output constant 211 that is indicative of the calculated signal 208 . For exemplary purposes, the calculated signal 208 is a result of adding the boom and stick command signals 203 , 209 . The subtraction factor map 206 includes a pre-defined map 210 on an X and Y axis. The X axis represents the calculated signal 208 , with a scale of −2000 to +2000, indicative of the calculated signal maximum and minimum values, and the Y axis represents the subtraction factor map output constant 211 with a scale of 0 to 0.5, indicative of the subtraction factor map output constant 211 maximum and minimum values. The calculated signal 208 between 0 and −1000 would provide a proportional subtraction factor map output constant 211 of 0.5 to 0, respectively. The calculated signal 208 between 0 and +1000 would provide a proportional subtraction factor map output constant 211 of 0.5 to 0, respectively. The calculated signal 208 less than −1000 and greater than +1000 would provide a subtraction factor map output constant 211 of 0. A stick map 212 receives the stick command signal 209 from the control device 122 that is indicative of the lever signal from the plurality of levers 120 . The stick map 212 provides a stick map output constant 213 that is indicative of the stick command signal 209 . For exemplary purposes, the stick map 212 includes a pre-defined map 214 on an X and Y axis. The X axis represents the stick command signal 209 , with a scale of −1000 to +1000, indicative of the stick command signal 209 maximum and minimum values, and the Y axis represents the stick map output constant 213 with a scale of 0 to 1, indicative of the stick map output constant 211 maximum and minimum values. The stick command signal 209 between −700 and −1000 would provide the stick map output constant 213 of 1. The stick command signal 209 between −700 and 0 would provide the proportional stick map output constant 213 of 1 to 0, respectively. The stick command signal 209 of greater than 0 would provide the stick map output constant 213 of 0. Calculating the boom, subtraction factor, and stick output constants 205 , 211 , and 213 provides a final subtraction factor 216 . For example, the boom, subtraction factor, and stick output constants 205 , 211 , and 213 are multiplied together to produce the final subtraction factor 216 . The range of the final subtraction factor would be between 0 and 0.5, indicative of the maximum and minimum values of the multiplication of the boom, subtraction factor and stick output constant 205 , 211 , and 213 . Calculating the final subtraction factor 216 and a full boom constant 218 provides a pre-dampened modulating factor 219 . For example, the final subtraction factor 216 , with a range of 0 to 0.5 is subtracted from the full boom constant 218 of 1, indicative of a constant given to the maximum boom command signal 203 , to provide a pre-dampened modulating factor 219 of 0.5. The pre-dampened modulating factor 219 then passes through a rate limit control 220 , which is provided to control the rate at which the modulating factor 201 can increase or decrease with respect to time, to produce smooth transitions. For example, the rate limit control 220 would allow a change of modulating factor (MF) 201 of the magnitude of ΔMF/1 s. The modulating factor 201 is then provided to the control device 122 for modulating the boom command signal 203 . For example, the modulating factor 201 of 0.5 is multiplied by the boom command signal 203 of −1000. As a result, a percentage of the boom command signal 203 of −500 is sent to control the boom 104 . INDUSTRIAL APPLICABILITY When the operator is performing a linear function, the plurality of levers 120 are positioned to produce the desired direction and velocity of the boom 104 , stick 108 , and work implement 110 . The plurality of levers 120 send lever signals to the control device 122 where a calibration factor is applied to provide boom and stick command signals 203 , 209 . The boom and stick command signals 203 , 209 are sent by the control device 122 to the control the respective boom 104 and stick 108 , and rotate them respective of one another. The control device 122 executes the algorithm continually to provide a modulating factor 201 to the boom command signal 203 that is indicative of command signal mapping. Boom and stick command signals 203 , 209 are mapped using boom, subtraction factor, and stick pre-defined maps 204 , 210 , and 214 , to produce the subtraction factor 216 . Subtracting the subtraction factor 216 from the full boom constant 218 provides the pre-dampened modulating factor 219 . The rate limit control 220 applied to the pre-dampened modulating factor 219 provides a smooth transition in instantaneous of the modulating factor 201 . The modulating factor 201 is provided to the control device 122 for modulating the boom command signal 203 . The modulated boom command signal controls the boom rotation and allows coordination between the boom and stick to allow for linear movement of the work implement.

A method of modulating a boom assembly to perform in a linear manner. The boom assembly includes a boom and a stick. The method comprising the steps of sending at least one lever signal to a control device indicative of operator desired direction and desired velocity of the boom and the stick, calibrating the lever signals to provide a boom command signal and a stick command signal, applying an algorithm-to-the boom command signal and the stick command signal, which the algorithm uses command signal mapping, and providing a modulating factor to the control device as a result of the algorithm.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCES TO RELATED APPLICATIONS None. BACKGROUND OF THE INVENTION a. Field of the Invention The invention relates to devices related to devices for the removal and grading of snow, gravel and the like. In particular, the invention relates to devices intended to be removably attached to light utility vehicles, including pickups, suburbans, tahoes, and the like for removal and grading of snow and gravel. b. Description of the Prior Art Devices for grading and removing snow are well known. There are two basic types of snowplow devices: 1. Devices intended to be mounted on the front of a vehicle, such as U.S. Pat. No. Re. 35,700 to Watson, et al., for a Removable Snowplow Assembly With Pivotable Lift Stand; and 2. Devices intended to be mounted on the rear of a vehicle such as U.S. Pat. No. 5,595,007 to Biance, for a Trailer-Type Snowplow. There are advantages and disadvantages to both types of devices. For example, the devices mounted on the front of a vehicle tend to decrease the chances of the vehicle becoming stuck in the snow or gravel. That is because the snow or gravel is moved before the wheels contact the surface. That is, the wheels are rolling on ground that has already been plowed. Further, the front-mounted devices allow a driver of the vehicle to more easily keep an eye on the plowing operation. In addition, the front-mounted devices allow a user to more easily stack or pile-up the material being moved. Nevertheless, despite their advantages, there are also disadvantages to the front-mounted types of devices. For example, most vehicles do not have attached thereto the necessary hardware for mounting a front-mounted snowplow. Therefore, there are also a plurality of designs for rear-mounted snowplows. U.S. Pat. No. 5,595,007 to Biance, discloses such a trailer-type snowplow. Biance utilizes a "receiver hitch"--receiver hitch type mounting device. That is, the snowplow mechanism has a male portion adapted to be removably be received within a female portion of a bracket mounted to the vehicle. A pin passes through the male portion of the bracket and the female portion of the snowplow fixing them in relation to one another. The snowplow can easily be removed from t he vehicle by removing the bland sliding the male portion of the snowplow out of the female portion of the bracket. The advantages of the Biance device is that a user can easily remove the snowplow from the vehicle without unsightly and space consuming hardware being left thereon. Prior are devices required a user to leave a mounting bracket permanently attached to the vehicle. This mounting bracket typically detached to the bumper and other points on the vehicle, taking up space and detracting from the appearance of the vehicle. Another type of rear-mounted snowplow apparatus is disclosed in U.S. Pat. No. 5,265,355 to Daniels. Daniels device is a three-point mounted snowplow. That is, there is an attachment at a center of a rear bumper and on either end of a rear bumper of a vehicle. Daniels discloses a box-type blade device. It has a means for raising and lowering the blade (as did Biance). The device disclosed by Daniels is extremely heavy and relatively expensive to manufacture. The angle of the blade with respect to the rear bumper of the vehicle is fixed in the Daniels device. That is, there is no way to angle the blade so as to move it to one side of the vehicle or another. Given the currently available and known devices, there is a need for a plow device which is extremely simple and inexpensive to manufacture. There is also a need for a device which can be attached to existing trailer hitches on vehicles. Specifically, there is a need for a snowplow which attaches to standard trailer-towing balls on the bumpers of many vehicles. SUMMARY OF THE INVENTION In view of the foregoing disadvantages inherent in the known types of devices for the removal and grading of snow, gravel and the like, it is an object of the invention to provide an apparatus which overcomes the various disadvantages of the prior art. It is therefore an object of the invention to provide a snowplow which has a connection means capable of being attached to trailer-towing balls on the rear bumper of a vehicle. It is a further object of the invention to provide a simple means of transporting the plow when a user does not desire for the plow to be in contact with the ground. It is a also an object of the invention to provide a simple means for adjusting the angle of the blade with respect to the rear bumper of a vehicle. There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in this application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. Additional benefits and advantages of the present invention will become apparent in those skilled in the art to which the present invention relates from the subsequent description of the preferred embodiment and the appended claims, taken in conjunction with the accompanying drawings. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientist, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood and the objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein: FIG. 1 is a top view of the trailer-type floating snowplow. FIG. 2 is a side view of the trailer-type floating snowplow. FIG. 3 is a front view of the trailer-type floating snowplow. FIG. 4 is a rear view of the trailer-type floating snowplow. FIG. 5 is a detailed side view of an adjustable wheel mechanism. FIG. 6 is a bottom view of the same adjustable wheel mechanism shown in FIG. 5. FIG. 7 is a top view of one configuration of the trailer-type floating snowplow attached to a rear bumper of a vehicle. FIG. 8 is a side view of a second embodiment of the trailer-type floating snowplow attached to a vehicle with the scraping surface in contact with the ground. FIG. 9 is a side view of the same embodiment of the trailer-type floating snowplow with the fixed wheels in contact with the ground and the offset hitch plate attached to the lower ball of the reversible hitch. FIG. 10 is a detailed side view, partially in section, of the reversible hitch and offset hitch plate. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to the drawings, where like numerals represent like or parts, an apparatus 10 incorporating the principles of the present invention is generally illustrated in the figures. FIG. 1 shows the apparatus 10 in a first embodiment. The embodiment shown if FIG. 1 is the same as the embodiment shown in FIGS. 2 through 7. An alternative embodiment of the invention is shown in FIGS. 8 through 10. The embodiment shown in FIGS. 1 through 7 will be detailed first followed by a description of the embodiment shown in FIGS. 8 through 10. The trailer-type floating snowplow 10 holds a blade 12 for scraping snow, gravel, and the like. Preferably, the blade is made out of a hardened steel material, which is durable yet tough enough so that not to be brittle. The blade may be either straight or slightly concave with the concave portion facing the vehicle facing behind which it is being towed. As shown in FIGS. 1 through 7, the blade 12 is straight, while the blade 12 is shown as curved in FIGS. 8 and 9. The blade has a front 14 which faces the vehicle behind which it is being towed and a back 16 which faces away from the vehicle. A scraping surface 18 is defined along one of the long edges of the blade 12. A first hitch bar 24 is attached to the blade 12 by a first bar connection means 30 adjacent to a first end 20 of the blade. A second hitch bar 26 is attached to the blade 12 by a second bar connection means 32 at or near a center point between the first end 20 and second end 22 of the blade 12. The first and second hitch bars combined with the blade define a triangular shape. That is, the first and second hitch bars come together at a distal end. A crossbar 28 is disposed between the first and second hitch bars 24 and 26 somewhere between the blade and a point where they come together. The crossbar 28 provides additional stability to the first hitch bar 24 and the second hitch bar 26. At a point where the first hitch bar and the second hitch bar 24 and 26 come together, they are attached to a hitch plate 34. A releasable hitch 36 is also attached to the hitch plate 34. The releasable hitch is one of the commonly commercially available hitch means for engaging a ball-type hitch on a vehicle bumper. A multiplicity of places are available to accomplish this objective, and one skilled in the art would be aware of these types of devices for engaging a ball-type hitch. The releasable hitch 36 is shown attached to a first connection point 70 in FIG. 7. The first connection point 70 is preferably a ball-type hitch attached either directly to a bumper of a vehicle or to a receiver-type apparatus with a removable receiver hitch, and these devices are well known. In the first embodiment of the plow as shown in FIGS. 1 through 7, two wheels are attached to the blade adjacent to the scraping surface. The first wheel 38 detaches by means of a first wheel adjustment means 40. Similarly, a second wheel 42 is attached by means of a second wheel adjustment means 44. The attachment of the wheels is shown in detail in FIGS. 5 and 6. FIG. 5 is a side view of the wheel adjusting means 44. For each wheel, two Z-shaped members, 52a and 52b, are attached to the blade 12 by bolts 54. At least two bolts, 54a and 54b, are attached to each Z-shaped member 52. In cooperation, the two Z-shaped members for each wheel, 52a and 52b, define a channel for slidingly receiving a sliding member 56. The sliding member has attached to it two side plates, 58a and 58b. The side plates, 58a and 58b, angle downwardly and away from Z-shaped members, 52a and 52b. An axle 60 passes through the side plates, 58a and 58b, upon which is mounted a wheel 38 or 42. Adjusting holes 64 are defined through the two Z-shaped members. The adjusting holes 64 are in linear alignment, so that a removable locking pin 62 may pass there through. A corresponding hole defined in the sliding member 56 (hole now shown) so that when the removable locking pen 62 is passed through the adjusting hole 64, it fixes the sliding member 56 into place. FIG. 6 shows the sliding member 56 and the associated side plates 58 and wheels 38 and 42 in a first position, P1, and a second position in outline, P2. In position P1, the removable locking pin 62, is inserted through hole 64a. By contract, the sliding member 56 is slid upwardly in the channel defined by the two Z-shaped members, 52a and 52b, to a second position as shown by P2. At position P2, the removable locking pin 62 passes through hole 64b to fix the wheel in place. It will be noted that at position P1, the wheel is in contact with the material to be graded and/or the roadway. Whereas in position P2, the wheels, 38 and 42, are above the scraping surface 18 of the blade 12. A chain 46 is attached to the blade 12 near the second end 22. The chain is attached via a chain attachment means 48. Basically, the chain attachment means is a bracket which is drilled through the blade with bolts on the back side. The chain 46 is then attached to the chain attachment means 48. The chain is of a slightly longer length than the first and second bar connection means. At an end opposite of the point where it connects to the chain attachment means 48, an adjustable chain loop 50 is defined. The adjustable chain loop 50 is created by taking a portion of the chain's 46 length and doubling it back. A mechanism is then inserted between two of the chain links to create a loop. This mechanism must be releasable (such as a bolt nut which can be tightened or loosened). The chain 46 is used to fix the angle of the blade relatively to the rear bumper of a vehicle. This principle is illustrated in FIG. 7. As shown, the adjustable chain loop 50 is looped around a second connection point 72. The releasable hitch 36 is attached to a first connection point 70. Both connection points are fixed on a bumper 68 of a vehicle 66. Thus the blade is attached to the vehicle 66 at a fixed angle. If the adjustable chain loop 50 is used to shorten the chain 46, the second end 22 of the blade 12 is moved closer towards the bumper 68 of the vehicle 66. Conversely, if the adjustable chain loop 50 is used to shorten the chain 46, the second end 22 is moved farther away from the bumper 68. An alternative embodiment of the plow 10 is shown in FIGS. 8 through 10. The alternative embodiment in FIGS. 8 through 10 is simpler than the embodiment shown in FIGS. 1 through 7. It incorporates a reversible hitch 74. The reversible hitch 74 has an upper ball 76 and a lower ball 78. The reversible hitch may be either mounted to the bumper or may be a receiver-type hitch which is inserted into a receiver just below the bumper of the vehicle. The means of mounting the reversible hitch is immaterial to the invention. However, if a receiver-type mechanism is used, it is not necessary to have both an upper ball 76 and a lower ball 78. Where a receiver-type hitch is used, the receiver can be removed and turned 180° to rotate the ball to either an up position or a down position. An offset hitch plate 80 is designed to operate with the reversible hitch 74. The offset hitch plate maintains the first and second hitch bars is a position substantially parallel with the ground whether the releasable hitch 36 is engaged with the upper ball 76 or the lower ball 78. FIG. 8 shows the releasable hitch engaged with the upper ball 76. FIG. 9 shows the releasable hitch 36 engaged with the lower ball 78. This embodiment incorporates a fixed wheel 82. Whereas the other embodiment of the plow incorporated a wheel adjustment means 40 and 44. The alternative embodiment discussed now does not allow for adjustment of the wheels' 82 position. FIG. 10 is a partial cross-sectional detailed view of the reversible hitch 74, including the upper ball 76, the lower ball 78, and the releasable hitch 36, along with the offset hitch plate 80. OPERATION OF APPARATUS In operation, the plow 10 typically is attached to a ball-type connection means on a rear bumper of a vehicle. In a first embodiment of the invention, the user attaches the releasable hitch 36 to the ball. The user then adjusts the first and second wheel adjustment means, 40 and 42, to place the scraping surface 18 in operative contact with the bulk material to be plowed. The user accomplishes the adjustment by removing the removable locking pin 62, adjusting the sliding member to place the wheels in the desired position, then re-inserting the removable locking pin 62 into the appropriate adjusting hole 64. A user then adjusts the adjustable chain loop 50 to give the desired length of chain 46. The adjustable chain loop 50 is then placed on the second connection point 72 on the vehicle's bumper. Placing the adjustable chain loop 50 over the second connection point fixes the angle of the blade 12 with respect to the vehicle's bumper. This effect can be seen by referring to FIG. 7. If a user desired to move the second end 22 closer to the vehicle's bumper, he would simply increase the adjustable loop's diameter 50, decreasing the length of the chain 46, and moving the second end 22 closer to the vehicle's bumper. The procedure regarding the chain 46 is the same regardless of whether the first embodiment or the second embodiment of the invention is used. In the second embodiment of the invention, a user will rotate the blade 12 so that the scraping surface 18 is in contact with the material to be plowed. This may be accomplished by several means. For example, a user can grasp the hitch plate lifting it upwardly and tilting the blade onto its back surface 16. Upon continuing to push on the hitch plate and/or the first and/or second hitch bars, 24 and 26, the plow 10 will rotate onto the scraping surface. The reverse process may be employed to rotate the plow 10 onto the fixed wheels. The releasable hitch 36 is then attached to the appropriate ball, either the upper ball 76 for plowing, or the lower ball 78 for towing the fixed wheels in contact with the roadway.

An adjustable grading device attaching to a vehicle rear towing hitch having a grading blade for grading or snow removal and integrated wheels for transport.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION The present invention is related to systems and methods of constructing highway bridges, traffic overpasses, causeways and the like, and more particularly, to a bridge constructing system using light weight lifting equipment and modular light weight structural elements, wherein the system integrates the lifting equipment with the structure being erected using the structure as a crane platform. Construction of highway bridges and causeways requires special high capacity lifting equipment, typically cranes. In most cases, lifting is performed by cables or hydraulic jacks, providing three or one degrees of freedom movement, respectively. Precise load positioning and orientation of the load (roll, pitch and yaw) is achieved by pulling with auxiliary tie lines or pushing with poles, jacks or other external devices. Lifting, carrying and final positioning of a payload that is not fully constrained results in pendulation and rotation of the payload, which reduces safety, requires more time to damp motion, and in harsh environmental situations, such as high winds, may cause shutdown and postponement of the lifting operation. Feasibility, cost and construction time for erecting highway bridges and causeway structures is typically governed by the assembly method, capacity of available lifting equipment, weight and number of the structural elements, organization of a staging-storage area and transporting the structural elements and lifting equipment from the production site to the erection site. Use of large preassembled structural elements can substantially reduce construction time and cost. However, handling of the large structural elements typically requires heavy lifting equipment, such as cranes having spreader bars. If the assembly cranes are heavier than the load that the bridge or causeway is intended to carry, the assembled structure may have to be overdesigned to support the assembly equipment. The following publications are related to construction of bridge structures. U.S. Pat. No. 3,845,515 to Gelhard et al. discloses a system for self-advancing construction of a conduit line. A railway is mounted on each side of the conduit. An assembly scaffolding capable of motion is suspended from the rails and is provided with a progressing erection component cantilevered to overhang the most forward assembled conduit section. The scaffolding accepts construction components and progressively erects the components along an intended route. The assembly scaffold is comprised of several connected, mutually supported and series-arrayed assembly sections. The front section of the assembly structure is developed into a cantilevered erecting section, while the most rearward assembly section is developed into a cantilevered material receiving section. Sections in between the front and rear cantilever sections are provided with controlled suspensions. An assembly scaffold consisting of several sections is thus suspended from its middle sections on travel rails of the previously erected pipe railroad section, and may be supplied with construction material from the rear. The materials are then transported to the front progressing sections of the structure where they are used by the cantilevered construction equipment to construct a further forward section of the pipe railroad. When construction of that section is completed, the entire assembly scaffold may move forward by the corresponding new segment, and a new section may be begun. U.S. Pat. No. 3,385,455 to Dal Pont discloses an apparatus for lifting, horizontally transporting and installing heavy loads, such as metal lattice trusses, between spaced apart vertical support points. The apparatus comprises spaced apart first and second vertical support means against which rests each end of a horizontally extending boom and respective tackle means supported from spaced apart points along the boom. The boom and support means constitute a rigid stationary structural assembly while a load is being moved between the vertical support points. The assembly is transferable as a unit to other locations. U.S. Pat. No. 4,282,978 to Zambon discloses a bridge crane comprising a framework consisting of a pair of parallel trusses interconnected by end portals and long enough to extend across three piers. Each truss has a bottom stringer formed on its underside with tracks engaged above each pier by rollers mounted on a pair of rocker arms, which are part of an undercarriage movable on transverse guide rails. Top stringers of the trusses support a trolley carrying hoists for raising and lowering transported castings. Longitudinal movement of the framework relative to the piers is brought about by a motor-driven capstan carried on the framework. U.S. Pat. No. 3,902,212 to Muller discloses a device for use in building the superstructure of a multispan civil engineering work, such as a bridge or elevated road. The superstructure comprises at least one two-arm beam extending in a longitudinal direction substantially symmetrically on both sides of a previously erected pier. The device is comprised of a raised elongated scaffold E having a median support adapted to rest on the pier. The scaffold includes booms 1, 2 and 3. The booms 1 and 2 constitute rolling tracks for carriages 4 and 5. European Publication 0 102 900 A2 discloses a beam positioning system having two parallel horizontal frames spanning over three columns. Each frame has a top rolling track for mobile bogies that move astride the frames and carry beam lifters. Each frame has a parallel bottom rolling track for rollers at the top of each column. Japanese Publication 1-310003 (A) discloses a bridge building method using a traveling frame lockable on an existing beam, a lifter type crane, and a means to hang/support a beam block from the lifter type crane. Soviet Publication SU 908989 discloses a gantry type bridge erection crane including a load carriage supporting beam 2, hinged and fixed legs 8 and 10 and an operating mechanism. After bridge supports and beams 12 and 13 are erected, crane columns 7, in the next span are jacked up and mounted on the erected bridge beams. The crane beam is then transferred to a new erection position, the crane columns lowered, and freed temporary supports 4 moved forward. Soviet Publication SU 1096328 A discloses a bridge span assembly method using mobile support gantries of adjustable height. U.S. Pat. No. 3,027,633 to Murphy discloses a method and apparatus for bridge construction in which a light-weight, temporary erection span 11 is erected on a barge 12, hoisted into position between two bridge piers, and used as a working platform for erecting a bridge span. The method includes a deck traveler 17 equipped with two stiff-leg derricks 17a and 17b mounted on a completed bridge span 18 and moving on skid beams mounted on the upper floor beams of the completed bridge span. U.S. Pat. No. 3,571,835 to Buechler discloses an apparatus for concreting multiple section elevated structures. The apparatus comprises two girders that are movable relative to one another. One of the girders is a scaffold girder, and the other is an advancing girder that supports the scaffold girder as it is advanced. SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved construction system and method that overcomes the above-described problems. It is another object of the invention to provide an improved system for rapid, safe construction of highway bridges, overpasses, bypasses and causeways. These and other objects of the invention are achieved by providing a crane capable of lifting and carrying modular bridge sections for overpass bridge construction, including a first supporting leg frame including a first pair of supporting legs, each of the legs including structure providing mobility of the crane and having a first length, a second supporting leg frame including a second pair of supporting legs, each of the legs including structure providing mobility of the crane and having a second length, longer than the first length, and a beam or truss connected between the first and second pairs of supporting leg frames, the beam or truss supporting heavy-lift corner cables capable of lifting and carrying the modular bridge sections. The first supporting leg frame is movable on an installed bridge section fixed to an existing section, and the second supporting leg frame is movable on the existing section. The crane may also include at least one light-lift platform movably supported by the frame and capable of assembling the modular bridge sections. Four to six heavy-lift corner cables, each driven by a winch may be provided, wherein each of the cables is disposed at a corner section of the crane. At least one of the first and second supporting leg frames may be adjustable. In accordance with another aspect of the invention, there is provided a lifting system including a frame and a plurality of cables for lifting and carrying a payload, wherein the cables are arranged to support the payload in six degrees of freedom, and the payload is used as a lifting platform. In accordance with yet another aspect of the invention, there is provided a method of constructing a bridge structure using a cantilever crane, the cantilever crane including structure capable of lifting and carrying modular bridge sections, and the method including the steps of: (a) assembling an initial bridge section having a predetermined length; (b) installing the initial bridge section; (c) placing the crane on the initial bridge section; (d) assembling with the crane a subsequent bridge section using one of the initial bridge section and a previous subsequent bridge section as a staging platform; (e) lifting the subsequent bridge section with the crane and stabilizing the subsequent bridge section; (f) moving and carrying the subsequent bridge section to a next position; (g) attaching the subsequent bridge section to the bridge structure; and (h) repeating steps (d) through (g) until the bridge structure is completely constructed. The crane may include at least one or more light-lift platform, wherein the lifting and stabilizing step includes stabilizing the subsequent bridge section in six degrees of freedom. The crane may further include a plurality of heavy-lift corner cables, wherein the lifting step comprises securing the heavy-lift corner cables to the subsequent bridge section and lifting the subsequent bridge section with the cables. The moving and carrying step and the attaching step may comprise positioning and attaching spudwells and pilings to an end of the subsequent bridge section. In addition, the assembling step may include assembling two skeleton sections on top of the initial bridge section, wherein the placing step comprises placing the crane on the sides of the skeleton sections such that the crane supports each of the skeleton sections on opposite sides thereof, each of the skeleton sections including legs with spud cans displaceable between a transport position and an extension position, and wherein prior to the attaching step, the method including lowering the legs from the transport position to the extension position. In accordance with yet another aspect of the invention, there is provided a method of constructing a bridge structure using a crane, the crane including structure capable of lifting and carrying modular bridge sections, the method including the steps of: (a) assembling an initial bridge section having a predetermined length; (b) installing the initial bridge section; (c) assembling two skeleton bridge sections on the initial bridge section, the two skeleton bridge sections each having supporting legs with spud cans displaceable between a transport position and an extension position; (d) placing the crane on the two skeleton bridge sections and attaching the skeleton bridge sections to front and rear portions of the crane, respectively; (e) moving the crane and the skeleton bridge sections such that the skeleton section attached to the first portion of the crane approaches a next position; (f) attaching the skeleton section attached to the front portion of the crane to the bridge structure in the next position; (g) lowering the legs of the skeleton section attached to the front portion of the crane from the transport position to the extension position and lowering the spud cans; (h) releasing the skeleton section attached to the rear portion of the crane; (i) positioning a subsequent skeleton section behind the skeleton section previously attached to the rear portion of the crane; (j) moving the crane such that the skeleton section previously attached to the rear portion of the crane is adjacent the front portion of the crane and the subsequent skeleton section is adjacent the rear portion of the crane; (k) attaching the front and rear portions of the crane to the skeleton sections, respectively; and (l) repeating steps (e) through (k) until the bridge structure is completely constructed. In accordance with still another aspect of the invention, there is provided a counterweight lifting system for lifting and carrying a first payload and a second payload, wherein the counterweight lifting system is movably attachable to the first and second payloads on opposite sides of a centerpoint, and a weight of one of the first and second payloads is used to lift a weight of the other of the first and second payloads. BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects and advantages of the present invention will become apparent from the following detailed description of preferred embodiments when taken in conjunction with the accompanying drawings, in which: FIG. 1 illustrates a crane in position on a bridge and a first assembled section of an overpass in accordance with a first embodiment of the invention; FIG. 2 shows the light-lift platforms assembling overpass components; FIG. 3 shows the completed skeleton section of the overpass bridge; FIG. 4 illustrates the completed skeleton bridge section prior to its attachment to the bridge structure; FIG. 5 is a closeup view of the winch and heavy lift cables in the first embodiment; FIG. 6 illustrates a cantilever crane installed on top of a first completed bridge section in accordance with a second embodiment of the invention; FIG. 7 illustrates the cantilever crane assembling a bridge component skeleton section; FIG. 8 shows the cantilever crane moving the completed bridge section forward for attachment to the bridge structure; FIG. 9 shows the skeleton section attached to the bridge structure; FIG. 10 illustrates the cantilever crane in a next position for .assembly of the next section; FIG. 11 illustrates a counterweight crane carrying a skeleton section positioned on top of a skeleton causeway section in accordance with a third embodiment of the invention; FIG. 12 shows the counterweight crane advancing the skeleton section to a next position; FIG. 13 shows the skeleton section attached to the bridge structure; and FIG. 14 shows the causeway counterweight crane separated from the attached skeleton section and ready to move backward and receive a new skeleton section. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1, the construction system of a first embodiment utilizes four preferably 42 foot sections of preassembled overpass 10 that are installed on an initial section of an existing bridge 12 using a conventional crane. The overpass crane 14 is preassembled and installed on the 168 foot section of overpass and the existing bridge as illustrated in FIG. 1. The overpass crane 14 includes a first frame of supporting legs 16 each comprising wheels 18 adapted to roll on rails 20. A second frame of supporting legs 22 similarly includes wheels 24 for rolling on rails 26. Although wheels 18 and 24 are illustrated in the figures, any suitable structure providing mobility of the crane can be used, and the invention is not meant to be limited thereto. Supporting legs 22 are about two times the length of supporting legs 16 so that the crane 14 maintains an almost level attitude while simultaneously engaging the existing bridge 12 and the overpass sections 10. In one embodiment the legs are adjustable via a telescoping arrangement (shown in phantom in FIG. 1). A longitudinal truss structure 28 is connected between the first and second frames of supporting legs. Referring to FIG. 5, the overpass crane 14 includes heavy lift corner cables 30 disposed at the corners of the crane 14 and driven by a winch 32 disposed on the frame of supporting legs. The longitudinal truss 28 movably supports two light lift platforms 34 that are capable of supporting a load in six degrees of freedom. Such a platform is known in, for example, U.S. Pat. No. 4,666,362 to Landsberger et al. and U.S. Pat. No. 4,883,184 to Albus, the disclosures of which are hereby incorporated by reference. The light-lift platforms 34 are used for constructing modular bridge sections in a known manner using an installed overpass section as a staging platform (see FIG. 2). In addition, the light-lift platforms stabilize the assembled skeleton overpass section 36 during transport (see FIG. 3). Referring to FIGS. 2 and 3, the light-lift platforms assemble columns 101, transverse beams 102, longitudinal trusses 103, and longitudinal ties 104 to complete a skeleton overpass section 36. The heavy-lift corner cables are secured to the completed skeleton preferably using a conventional twist-lock structure such that the completed skeleton overpass section 36 acts as a lifting platform, replacing the heavy spreader bar of the conventional crane. Using the heavy-lift corner cables 30 and winch 32 to lift the skeleton section 36 and the light lift platforms 34 to stabilize the skeleton section 36, the crane 14 is rolled forwardly, carrying the completed skeleton section for attachment in a next position, as illustrated in FIG. 4. The light-lift platforms 34 add deck sections to complete the overpass section. The crane 14 is then ready to construct another skeleton overpass section using the just installed overpass section as a staging platform. The truss structure of the overpass sections is generally known and will not be described in detail. Examples include U.S. Pat. No. 4,907,390 to Tene and U.S. Pat. No. 4,827,688 to Tene, the disclosures of which are hereby incorporated by reference. Because the overpass crane 14 including supporting leg frames 16,22 rides on rails outside and/or above traffic lanes, the construction system allows overpasses or bypasses to be constructed without interrupting traffic flow all or most of the time. In one alternative arrangement, the crane is constructed without light lift platforms 34 and includes six to eight corner cables. The corner cables are distributed from each corner to a midpoint of a respective side of the skeleton section 36, providing support for the skeleton section 36 in six degrees of freedom. Referring to FIG. 6, a construction system of a second embodiment is illustrated in accordance with a cantilever crane 40. In the initial bridge construction, four preferably 42 foot sections of bridge are constructed on land accessible to a conventional crane. The preassembled sections are installed using a conventional crane. A cantilever crane 40 is assembled on top of the completed bridge section as illustrated in FIG. 6. The cantilever crane 40 includes a light lift platform 34 to assemble columns, transverse beams, longitudinal trusses and longitudinal ties as discussed above to complete the skeleton of a preferably 168 foot bridge section as it is pushed forward by a truck or pulled by cables and winches (illustrated in FIG. 7). The light-lift platform 34 also positions and attaches spudwells 42 and pilings 44 to the end of the skeleton section (illustrated in FIG. 9). The cables supporting light-lift platform 34 are reeved around pulleys fixed to corners of the cantilever crane. The heavy-lift cables of the causeway crane are attached to the skeleton using the twist-lock connector described above, and the completed skeleton causeway section is moved forward to a next position as illustrated in FIG. 8. Thus, the completed skeleton acts as a lifting platform, replacing the heavy spreader bar of the conventional crane. The piles are lowered and driven in a known manner until the causeway section is fully supported. Piles are preferable attached every fourth bridge section. Finally, the causeway section is completed by installing the remainder of the trusses and deck plates. As shown in FIG. 10, the cantilever causeway crane 40 is then moved forward to the end of the completed section. The frame components are preferably formed of axially loaded structural elements to substantially reduce the weight of the structure supporting the payload, pulleys and winches, its own weight, windloads and dynamic effects caused by moving the payload and the like during the assembly process. As a result, the maximum load supported by the substructure and foundations during the construction process is preferably no greater than their load bearing capacity during operation. The crane structure is designed with axially loaded structural elements carrying the main vertical loads. By having the main lifting cables attached to the four corners of the crane structures, the load is transferred directly to the legs, and axial loads are introduced to the top members of the frames of supporting legs and top members of the longitudinal trusses 28. The light lift platforms, used to assemble much lighter components, are likewise made of cables and axially loaded elements. Axially loaded elements, cables and trusses utilize the maximum allowable stresses over their whole section and are therefore lighter and more effective than bending elements (beams) where the maximum allowable stresses are utilized only at extreme edges or corners. This design criteria leads to lighter structure of the overpass bridge, which in turn enables reduction in weight of the lifting equipment and reduction of the additional loads imposed on the existing bridge. These weight savings can be applied to achieve cost savings, reduced construction time and increase the span of bridges and causeways. Referring to FIG. 11, a construction system of a third embodiment is illustrated in accordance with a counterweight bridge crane 50. In this construction, two or more complete, preferably 168 foot bridge or causeway sections are assembled by conventional cranes where there is access such as on land, on a quay, or from a ship or barge. After installation of the preassembled sections, two skeleton sections, preferably each 168 feet long, are assembled on top of the completed bridge or causeway. As shown in FIG. 11, the counterweight crane 50 is assembled on top of the skeleton section. The counterweight crane rear frame 48 is attached to the rear section 52 of the skeleton section while the front frame 60 of the counterweight crane is attached to the front section 54. Wheels 68' fixed to counterweight crane 50 are disposed above and below a rail fixed to the skeleton sections. Wheels 68' are selectively lockable on the rail to prevent movement. The rear frame 48, supported by rear cables 62 attached to the top of center frame 56 utilizes the weight of skeleton section 52 and additional bridge components like decks and nestable trusses as counterweight for lifting and lowering into place the front skeleton section 54. The front skeleton section 54 is suspended from the crane front frame 60 and the center cables 66. The front frame is supported to the top of center frame 56 by front cables 64. Skeleton section 52 rides on the assembled bridge using wheels 68 or the like. A service car with crane 70 can move on the front frame 60 to assist in connecting the center cables 66 to the front skeleton section 54 and in lowering the front legs 58. The two skeleton sections 52 and 54 together with the counterweight crane 50 are rolled forward on wheels 68, to the new position (FIG. 12) where section 54 is above its final position in the bridge. A new, preferably 168 foot skeleton section 74 is then attached to the rear of skeleton section 52. Referring to FIG. 12, as the crane 50 together with the first skeleton section 52 and the second section 54 are rolled forward, spud cans and legs 58 are lowered from a transport position (FIG. 11) to an extension position (FIGS. 12 and 13). The counterweight crane 50 lifts the second section 54 of the skeleton, pushes it forward using compression rods 72, and lowers it into final position as shown in FIG. 13 using the rear section 52 as additional counterweight. The forward ends of the compression rods 72 are disconnected, and the front legs are adjusted to fully support skeleton section 54. The front frame 60 and service car 70 are lifted back using the front cables 64 and center cables 66 using a compression rods 72 (FIG. 14). Additional legs and spud cans 76 are attached to the new skeleton section 74, and the counterweight crane 50 is disconnected from skeleton section 52 and rolled backward. The crane 50 is attached to skeleton section 74 and the cycle repeats itself with section 52 becoming the "new" section 54 and section 74 becoming the "new" section 52. The crane 50 together with the two bridge skeleton sections 52 and 74 ("new" 52, 54) are rolled forward to the same position described in FIG. 11. While the invention has been described in detail with reference to preferred embodiments thereof, which are intended to be illustrative but not limiting, various modifications of the present invention may be made without departing from the spirit and scope of the invention, which is defined by the following claims.

A system for rapid, cost-effective construction of highway bridges, trafficverpasses and bypasses, and causeways over water or wetlands utilizes light-lift crane structures together with modular, light-lift bridge sections and an enhanced stabilized crane, using controlled cables, to improve the safety and efficiency of the construction process. Stabilization of the payload against pendulation and rotation enables safe operation in harsh environmental situations such as wind. The construction system utilizes continuous site assembly processes for building bridges and causeways from repetitive modular elements. In some embodiments, the system uses the payload (one or more modular bridge sections) as a component of a stable lifting and positioning system, thereby eliminating the need for heavy auxiliary lifting equipment such as spreader bars and platforms. Lifting cables of the crane are directly attached to the bridge payload, which becomes part of the lifting system during placement. Other embodiments utilize installed modular elements as a staging platform for constructing subsequent modular elements.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS This application claims the benefit of an earlier filing date from U.S. Provisional Application Ser. No. 60/356,712 filed Feb. 13, 2002, the entire disclosure of which is incorporated herein by reference. BACKGROUND The hydrocarbon recovery industry has embraced multilateral wellbores to enhance volumetric and qualitative recovery of specified hydrocarbons while minimizing earth surface impact. Multilateral wellbores, simply put, are those where a primary borehole is drilled from the earth's surface and at least one “lateral” borehole diverges from that primary wellbore somewhere underground. As a practical matter, there are more than one lateral borehole extending from a primary borehole. Multilateral wellbores employ junctions to mate a primary wellbore to its lateral boreholes. Whether the bores be cased or uncased, generally the junction is larger in outside dimension than the primary wellbore through which it must pass to arrive at the site of lateral exit. One way to deal with this issue is to form the junction at the surface and then deform the legs and primary sections thereof so it has a temporary outside dimension smaller than the I.D. of the primary wellbore through which it will be delivered to its installation site. Once at its installation site, the junction is swaged back to near its original shape. Unfortunately, swaging can be damaging to the material of the junction and is effort intensive. SUMMARY A multilateral junction comprises a primary leg and one or more lateral legs. Each end of the primary leg and each lateral leg has an inflatable element therein. A method for installing a multilateral junction includes running a deformed junction to depth and serially or collectively inflating an inflatable element in each leg of said junction to reform said junction. BRIEF DESCRIPTION OF THE DRAWINGS Referring now to the drawings wherein like elements are numbered alike in the several Figures: FIG. 1 is a perspective view of a multilateral junction in undeformed condition; FIG. 2 is a perspective view of a multilateral junction in deformed condition; FIG. 3 is a perspective view of FIG. 2 with inflatable elements installed therein; FIG. 4 is a perspective view of the junction with elements inflated; and FIG. 5 is a perspective view of the junction with the snobblin bar being pressure reformed. DETAILED DESCRIPTION Referring initially to FIG. 1, a typical junction shape for installation at the junction between a primary bore and a lateral bore is illustrated. The junction 10 is built prior to being installed in a wellbore, generally at a factory. For the following discussion, different areas of the junction are to be considered separate. They are lateral leg 12 , primary end 14 , primary end 16 and snobblin bar 18 . It is also important to note that for purposes of this application the terms “one end” and “another end” as used with respect to junction 10 are merely used to distinguish between two different areas of the primary borehole section of the junction. They could easily be switched, and have no significance with respect to flow direction or order of the components. A snobblin bar is known in the vernacular of this particular art as that section of a junction having a FIG. 8 appearance where the junction is viewed in cross-section. Such a device as shown in FIG. 1 does not fit through the I.D. of a casing string (not shown) which is generally very slightly larger than the O.D. of, for example, primary end 16 . Thus, in order to deliver junction 10 to the desired deployment location it is a practice within the industry to deform the junction as illustrated in FIG. 2 . Reforming the junction after positioning at the desired location is important to its functionality and has been done in the art by means of a mechanical swage. It is desirable however to avoid the work required with the use of a mechanical swage. The inventor of the present disclosure seeks to inflate the deformed junction, as illustrated in FIG. 2, back to a substantial facsimile of its original shape, as illustrated in FIG. 1 . The different sections of the junction, i.e., 12 , 14 , 16 and 18 as identified above require different pressures to undeform them and each has different maximum pressure limits before which such section will rupture. In one example, section 12 would require in excess of 7000 pounds per square inch (hereinafter “psi”) to resume a round shape whereas primary end portion 14 only requires 3000 psi to be rendered substantially round and would rupture at pressures significantly above 3000 psi (and well before the 7000 psi required to reform leg 12 ). Similar to portion 14 , primary end portion 16 requires approximately 3000 psi to attain a round shape. Again, substantially in excess of 3000 psi at 16 may cause structural problems with the junction. For obvious reasons then, simply pressuring up on the tubing is not an effective way of reforming the junction. Importantly, the snobblin bar 18 is a relatively weak section of the junction and can only maintain about 2500 psi. Substantially more pressure could easily rupture the snobblin bar. The inventor hereof has overcome the problem associated with reforming a deformed junction with fluid pressure by employing three separate inflatable elements which can be seen illustrated in situ in FIG. 3 . Element 20 is disposed within the lateral section 12 of junction 10 , element 22 is located in the primary end 16 and element 24 is located in the primary end 14 . In one embodiment, each of the inflatable elements are packers. It is noted that the inflatable elements 20 , 22 and 24 are, in this embodiment, installed in the junction after deforming, however, it is possible to have the inflatable elements installed within the junction 10 prior to deforming for ease of insertion. Since each of the elements is independent, different pressures are possible in specific areas of junction 10 which require them. For example, in this embodiment, inflatable element 20 will be pressured to about 7000 psi in order to straighten and round section 12 . Inflatable elements 22 and 24 will each be inflated to about 3000 psi in order to reform those sections of the junction. Because elements 22 and 24 are at about 3000 psi, element 20 is reduced from about 7000 psi after inflation, to about 3000 psi. Referring now to FIG. 4, the snobblin bar 18 is at this point segregated and pressure sealed from areas beyond the individual inflatable elements. This area is to be pressured from another location capable of producing and maintaining a pressure of about 2500 psi, i.e., sufficient to reform the snobblin bar area but avoid rupture. This can be accomplished by providing a fluid inlet anywhere within the area defined by inflatable elements 20 , 22 , 24 and the bridging sections of the junction 10 . In this embodiment, inflatable element 24 further includes a feed through arrangement such as that typified by Product number 300-02, commercially available from Baker Oil Tools, Houston, Tex. The feed through device, schematically illustrated at 26 , feeds pressure to the snobblin bar area 18 . Once the 2500 psi pressure has been given sufficient time, the snobblin bar area of junction 10 is reformed as illustrated in FIG. 5 . The inflatable elements may then be removed from the junction and further completion operations undertaken. In one embodiment of the method for creating the junction in the downhole environment, much of which has been disclosed above, the junction 10 is created and then deformed in a pattern known to the art. Inflatable elements are added to the deformed junction although as noted previously can be added prior to deforming. The inflatable elements are inflated either serially or collectively as desired and when set and stabilized, pressure is fed to the snobblin area. After a period of time of about 20 to about 30 minutes, the pressure is relieved from the snobblin area and relieved from the inflatable elements whereafter said elements may be removed from the junction. While preferred embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.

A multilateral junction comprises a primary leg and one or more lateral legs. Each end of the primary leg and each lateral leg has an inflatable element therein. A method for installing a multilateral junction includes running a deformed junction to depth and serially or collectively inflating an inflatable element in each leg of said junction to reform said junction.

You are an expert at summarizing long articles. Proceed to summarize the following text: RELATED APPLICATION [0001] This application is a continuation-in-part application of U.S. patent application Ser. No. 11/486,679, filed Jul. 14, 2006, the entire disclosure of which is hereby incorporated by reference. FIELD OF THE INVENTION [0002] The invention relates to moveable strip door suspension systems and methods that provide a barrier that moves along a rail and a roller track in a room or vehicle. The barrier may be positioned and releasably locked into position at any point along the rail/roller track system. In an embodiment, the barrier is a thermal barrier or insect barrier, for example. BACKGROUND OF THE INVENTION [0003] Storing, transporting and delivering refrigerated goods requires the use of a room or vehicle equipped with a refrigeration or freezer unit or other means of cooling the air within the room or vehicle sufficiently to protect the cargo. One of the most obvious examples of such cargo is refrigerated or frozen foods or medical supplies which, if allowed to warm or thaw, are no longer useable or saleable. [0004] If a vehicle is fully loaded at a single loading site and transported to an unloading site where it is fully unloaded, problems with respect to maintaining a sufficiently cool temperature are not necessarily encountered. However, when a vehicle is not fully loaded and/or is loaded at multiple loading sites and/or unloaded at multiple unloading sites, the risk of loss of refrigeration or increased expense for maintaining a proper refrigeration temperature increases. As delivery proceeds, the vehicle becomes partially emptied. This means that the refrigeration unit then cools not only the remaining cargo, but the empty portion of the vehicle. Each time the vehicle doors are opened and cargo is removed, cool air is lost and the warmer air that replaces it must then be cooled in order to protect the remaining cargo. As a consequence, cargo that is loaded first is also the cargo that is unloaded last and is thus subjected to the full effect of the warming and cooling cycles caused by repeatedly opening and closing the vehicle doors. [0005] One approach to maintaining the cooling capacity of a refrigerated vehicle has been to provide a movable bulkhead that can be repositioned along the vehicle's length. The bulkhead is used to close off that portion of the vehicle that still contains refrigerated goods. However, rigid bulkheads are expensive, complex, difficult to position, heavy, and must be moved each time the goods contained behind them are loaded or unloaded. While some such bulkheads have doors that can be opened, a majority of bulkheads are solid and it is impossible to see precisely what is behind them without first moving them. Further, known bulkheads in the art feature heavy mounting hardware, and are hinged such that the entire bulkhead is lifted and then positioned along the roof of the vehicle when not in use. Such doors are difficult to repair and represent a potential safety hazard should the door hardware fail. [0006] Strip curtains that span the width of a vehicle make it possible for a person to walk through the curtain without having to move it to one side and facilitate the on-loading and off-loading of cargo. However, where goods must be loaded in bulk, such as by forklift truck, it becomes extremely desirable to provide a way for the curtain to be moved from its position stretching across the load space to enable free access to the cargo or the cargo space. Without an easily operated structure to enable the movement of such a curtain along the vehicle length and across the vehicle width there is a tendency for the operator to use the strip curtain improperly. [0007] Another approach to providing temperature control is a curtain or door, fashioned either from overlapping vinyl strips or insulating “blankets” consisting of fabric sandwiched around an insulating core. The strips or blankets are secured along a horizontally extending overhead member. Vinyl strips are made of lightweight translucent or transparent vinyl material, allowing the cargo behind the strips to be seen, while avoiding the storage and manipulation problems inherent in the use of heavy, rigid bulkheads. Such strip curtains have been modified for use in vehicles by providing a horizontally extending aluminum support member from which the individual strips are suspended, and a track-and-trolley extending along the upper walls of the vehicle proximate the roof, whereby the horizontally extending support member can be positioned at various specific sites along the length of the vehicle (see, for example, U.S. Pat. No. 4,639,031 to Truckenbrodt). However, that patent discloses a locking system that can only engage with a series of holes placed at set intervals along the rail system it employs. In addition, the operator must undo the lock on one end of the system and pivot the system in order to move it to a different position in the vehicle. Such pivoting is difficult and dangerous if the operator is moving the system to the rear of a vehicle, because it requires the operator to leave the vehicle and step onto the ground, a docking board, scissor lift, or fork lift, thereby posing a safety issue. Another type of strip door, such as that manufactured by Kason Industries, is stationary and cannot be moved forward or backward inside a vehicle. Yet another system used in the past involves the permanent installation of a horizontal support member to the vehicle wall at a hinge which allows the strip curtain to be stored along the side wall of the vehicle, but does not allow the curtain to be repositioned along the length of the vehicle. [0008] Accordingly, the need exists for a lightweight, ergonomically designed, low maintenance, and flexible thermally insulating barrier that may be positioned at any point along the length of a vehicle, thereby varying the air space required to be cooled, while at the same time providing structure that enables the barrier to be moved to a loading or storage position along side one of the trailer's side walls. SUMMARY OF THE INVENTION [0009] The present invention relates to movable barrier systems that can be repositioned along the length or width of a room, building, container, or vehicle, for example, a truck, trailer, railroad car, aircraft hold, cart, or van. In an embodiment, the room, building, container, or vehicle is temperature controlled (e.g., refrigerated, freezing, or heated). The movable barrier systems and methods do not require pivoting of the barrier to reposition it, thereby making it safer and allowing the operator to stand within the trailer, for example, even when moving the barrier system to the rear of the vehicle. In addition, the movable barrier system provides a wider and higher insulated cargo space. [0010] In one aspect, the invention provides movable barrier systems extendable between two side walls. The systems includes a barrier, a transverse bar engaged with the barrier such that the barrier extends between the two side walls, one end of the transverse bar moveably engaged with a first support and a second end of the transverse bar moveably engaged with a second support. The system further comprises a releasable locking mechanism engaged with the first end of the transverse bar and the first support such that the locking mechanism can lock onto the first support, for example, by clamping it. In an embodiment, the releasable locking mechanism can lock onto the first support at any point as it travels along the first support. In an embodiment, the transverse bar is moveable along the first and second support without the need to disengage it therefrom in order to move the barrier. [0011] In an embodiment, the barrier is a thermal barrier (e.g., refrigeration or heat), such as a strip door or curtain; however any desired barrier, such as an insect barrier, is contemplated. In an embodiment, the barrier is formed from a plurality of strips, for example, thermoplastic sheeting or mesh. The barrier may be made of any suitable material, e.g., poly vinyl chloride, vinyl, and insulating fabric. [0012] In an embodiment, the first support comprises a rail, such as an I or T rail, extending along the first side wall. [0013] In an embodiment, the second support comprises a roller track extending along the second side wall. In an embodiment, the barrier system of the invention comprises a transverse bar that is engaged with a roller assembly that engages with the roller track. The roller assembly comprises at least one wheel. [0014] In an embodiment, the locking mechanism comprises a moving member for releasing the locking mechanism. The release handle may be, for example, a wand, twist rod, chain, or rope. BRIEF DESCRIPTION OF THE DRAWINGS [0015] The foregoing and other objects, features and advantages of the present invention, as well as the invention itself, will be more fully understood from the following description of preferred embodiments when read together with the accompanying drawings, in which: [0016] FIG. 1 provides a perspective view of moveable strip door suspension system mounted on a trailer's side walls according to an embodiment of the invention. [0017] FIG. 2 provides a perspective view of a moveable strip door suspension system according to an embodiment of the invention. [0018] FIG. 3 provides a perspective view of the releasable locking mechanism according to an embodiment of the invention. [0019] FIG. 4 a provides a top view of the releasable locking mechanism in an open position according to an embodiment of the invention. [0020] FIG. 4 b provides a close up of the cam portion of the releasable locking mechanism of FIG. 4 a in an open position according to an embodiment of the invention. [0021] FIG. 5 a provides a top view of the releasable locking mechanism in a closed position according to an embodiment of the invention. [0022] FIG. 5 b provides a close up of the cam portion of the releasable locking mechanism of FIG. 5 a in a closed position according to an embodiment of the invention. [0023] FIG. 6 provides a top perspective view of a releasable locking mechanism according to an embodiment of the invention including a bump stop that applies pressure to the first support. [0024] FIG. 7 provides a bottom perspective view of the releasable locking mechanism of FIG. 8 . [0025] FIG. 8 provides a top perspective view of a releasable locking mechanism according to an embodiment of the invention including a bump stop that applies pressure to the roller and the first support. [0026] FIG. 9 provides a side view of a pivot mechanism that will allow the strip door of the invention to be moved to a side of the container or truck. [0027] FIG. 10 provides a perspective view of a pivotable strip door suspension system according to an embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION [0028] FIG. 1 shows an embodiment of the invention comprising a trailer truck 1 with a temperature control unit (not specifically shown) for keeping the interior of the trailer truck 1 at a uniform temperature (e.g., cool or hot). The trailer truck 1 has a left (first) side wall 2 , a right (second) side wall 4 , a ceiling 6 , and a floor 8 . As shown in FIG. 1 , a moveable strip door suspension system 10 according to one embodiment of the invention is installed therein. The system 10 comprises a first support 12 disposed on the left side wall 2 , a second support 14 disposed on the right side wall 4 , a strip door 16 attached to a transverse bar 18 , having a first end 20 and a second end 22 , disposed there between, and a releasable locking mechanism 24 for locking the transverse bar 18 in a desirable place along the first and second supports 12 , 14 . The transverse bar 18 is moveable in both the forward and backward directions and can be locked in place using the releasable locking mechanism 24 , and unlocked and moved as desired. [0029] Referring now to FIG. 2 , the first support 12 is arranged in a fixed parallel spatial relationship with the second support 14 , along the left and right side walls 2 , 4 . In an embodiment, the first support 12 is an I rail and the second support 14 is a roller track. As shown in FIG. 1 , in an embodiment, the first and second supports 12 , 14 are placed proximal to the ceiling 6 , such that the amount of temperature controlled (e.g., cool) air escaping over the strip door 16 is minimized. If desired, additional strip door material or other suitable barrier (not shown) can be attached to the transverse bar 18 or strip door 16 such that it extends upward toward the ceiling 6 to further block the escape of temperature controlled air from the temperature controlled section of the trailer truck 1 . [0030] The first support 12 may be any suitable shape for allowing traversal by a releasable locking mechanism 24 . In certain embodiments, the first support 12 may be an I rail, a T rail, beam, cable, or the like. The first support 12 may be made of any suitably rigid material that can withstand the weight and movement stresses of the strip door 16 , for example, metal (e.g., aluminum, stainless steel, galvanized steel, HTP®), plastic, fiberglass, poly vinyl chloride, or the like. In an embodiment, the first support 12 further comprises apertures for bolting or screwing the first support 12 to the left side wall 2 (not shown). [0031] The second support 14 may be any suitable shape for allowing traversal by a roller 26 attached to the transverse bar 18 . In certain embodiments, the second support 14 may be a C rail. In other embodiments, the second support 14 is a trolley selected from a flat trolley or an eye manual trolley (e.g., as sold by Vestil Manufacturing Corporation, Angola, Ind.) or a track or the like, such as those sold by Richards-Wilcox, Inc. (Aurora, Ill.). The second support 14 may be made of any suitably rigid material that can withstand the weight and movement stresses of the strip door 16 , for example, aluminum, stainless steel, galvanized steel, HTP®, plastic, fiberglass, poly vinyl chloride, or the like. In an embodiment, the second support 14 further comprises holes for bolting or screwing the second support 14 to the right side wall 4 . [0032] In another embodiment, the orientation of the moveable strip door suspension system 10 is reversed such that the first support 12 is secured to the right side wall 4 and the second support 14 is secured to the left side wall 2 . Alternatively, the moveable strip door suspension system 10 is positioned along the length of the vehicle 1 , for example, if the door is located on the side of the vehicle. [0033] The strip door 16 may be attached to the transverse bar 18 by any number of securing means. FIG. 2 shows an embodiment of the invention in which the strip door 16 comprises a number of strips 28 that are attached to the transverse bar 18 by a plurality of bullet shaped members 30 , for example, as in the Maximus SysteM™ or MaxBullet™ mounting hardware sold by Aleco Corp. (Muscle Shoals, Ala.). Any alternative attachment is contemplated, including hooks, buttons, staples, rings, nuts and bolts, welded studs, or the like. The transverse bar 18 may be made of any suitably rigid material that can withstand the weight and movement stresses of the strip door 16 , for example, aluminum, stainless steel, galvanized steel, HTP®, plastic, fiberglass, poly vinyl chloride, or the like. [0034] The strips 28 and strip door 16 may be any desired width or length to span a desired space. For example, the strips 28 may be about 2, about 4, about 6, about 8, about 10, about 12, about 14, about 16, about 20, about 25, about 30, about 35, about 40, about 45, about 50, about 55, about 60, about 65, about 70, about 75, about 80, about 85, about 90, about 95, about 100, inches in width or any width there between. The strips 28 may be any suitable length depending on the height of the room, container or vehicle, for example, about 2 feet, about 4 feet, about 6 feet, about 8 feet, about 10 feet, about 12 feet, about 14 feet, about 16 feet, or any length there between. [0035] The strips 28 may be made of any useful thermal material, such as, for example, polyvinylchloride, vinyl, vinyl coated fabric, high mass vinyl, pre-coated woven vinyl coated mesh polyester screen, and insulating fabric, and may be clear, opaque, or any desired color, texture, or dimensions. The strips 28 may be any desired thermally insulating thickness, for example, about 0.040, about 0.050, about 0.10, about 0.15, about 0.20, about 0.25, about 0.30, about 0.35, about 0.40, about 0.45, or about 0.50 mm or any thickness there between. Suitable strip 28 material includes, for example, Clear-Flex II®, Hi-Viz®, and Scratch Guard® by Aleco Corp. (Muscle Shoals, Ala.) or Standard Smooth, USDA Low-Temp Smooth, USDA Low-Temp Reinforced, Anti-Static, Weld Screen, Opaque, Safety Orange, X-Low-Temp sold by Kason Industries, Inc. (Lynbrook, N.Y.) or strip doors such as Save-T® sold by TMI Inc. (Pittsburgh, Pa.), Verilon® Vinyl (Wheeling, Ill.), or those sold by Singer Safety Co. (Chicago, Ill.), Wilson Industries (Pomona, Calif.), or Strip-Curtains.com (Point Roberts, Wash.), for example. Alternatively, the strips 28 or strip door 16 may be comprised of a material (e.g., mesh strips) that keeps insects out of a portion of the trailer 1 . In an embodiment, the insect strips 28 are mesh strips made of pre-coated woven vinyl coated mesh polyester screen, such as Air-Flex sold by Aleco Corp. (Muscle Shoals, Ala.). [0036] Referring again to FIG. 2 , an embodiment of the movable strip door suspension system 10 is shown in more detail. In an embodiment, the first support 12 is I shaped and comprises a first end 31 and a second end 32 comprising a first side 34 and a second side 36 . The first side 34 of the first support 12 is placed against the left side wall 2 and the second side 36 engages with the releasable locking mechanism 24 . The second support 14 is C shaped and comprises a first end 38 and a second end 40 and a side 42 that is placed against the right side wall 4 . The second support 14 is engaged with a roller 26 , for example, such as the rollers sold by Action Industries (Cleveland, Ohio). In an embodiment, the roller 26 may be a utility hanger, caged roller bearing, ball bearing, or the like, such as those sold by Richards-Wilcox, Inc. (Aurora, Ill.). The roller 26 is rotatably engaged with a bracket 44 that is attached to the second end 22 of the transverse bar 18 and the first end 20 of the transverse bar 18 is attached to the releasable locking mechanism 24 . [0037] Referring now to FIG. 3 , in an embodiment of the invention, the releasable locking mechanism 24 clamps onto the first support 12 and is moveable anywhere along the first support 12 between the ends 31 , 32 . In an embodiment, the releasable locking mechanism 24 is a brake mechanism such as those described in U.S. Pat. Nos. 3,348,632 and 5,238,084 to Swager relating the Climber's Buddy sold by Sur Loc, Inc. (Fremont, Ind.) and US Patent Application No. 20030217887 to Thomas. The releasable locking mechanism 24 may be spring-biassed into frictional engagement with the first support member 12 . The releasable locking mechanism 24 may be a clamp, such as a girder clamp, a universal superclamp, a swivel or fixed jaw adjustable girder clamp, for example (i.e., as sold by Fastenal, Winona, Minn.), or the like, or other clip, cam, or lock that can move along a track and lock in place along the track. [0038] Referring to FIGS. 3-5 b , in an embodiment of the invention, the releasable locking mechanism 24 comprises side plates 46 , 48 , between which are disposed rollers 50 and a locking arm 52 comprising a cam 54 . The rollers 50 and the locking arm 52 of the releasable locking mechanism 24 are spaced to engage an H rail 12 and to allow for locking engagement with the cam 54 . In an embodiment, a spring (not shown) is mounted on each side of locking arm 52 , biasing the cam 54 against the H rail 12 . A bolt 56 passes through the side plates 46 , 48 to secure the releasable locking mechanism 24 to the transverse bar 18 . FIGS. 4 a and 4 b show a releasable locking mechanism 24 in the open position, in which the cam 54 is not pressing against the H rail 12 , and can be moved along the H rail 12 in either direction. FIGS. 5 a and 5 b show the releasable locking mechanism 24 in the locked position, in which the cam 54 is engaged with and locked against the H rail 12 . [0039] Referring again to FIG. 2 , in an embodiment, the releasable locking mechanism 24 further comprises a moving member 58 for use by the operator to grasp and push or pull to open and close the releasable locking mechanism 24 . In an embodiment, the moving member 58 is a wand, a twist rod, a chain, or a rope, for example. In another embodiment, the moving member 58 is a cargo bar or cargo strap that is already in the trailer for keeping the trailer contents securely in place (e.g., those sold by Vestil Manufacturing Corp., Angola, Ind.). The moving member 58 is useful for moving the strip door 16 forward and backward along the first and second supports 12 , 14 . [0040] Referring now to FIGS. 1-3 , the strip door 16 is initially positioned at a desired location within a vehicle 1 , with transverse bar 18 secured to the first support 12 . When it is desired to move the transverse bar 18 along the length of vehicle 1 , the releasable locking mechanism 24 is opened by moving the locking arm 52 either by hand or using a moving member 58 , for example. While holding the locking arm 52 in the open position as shown in FIGS. 4 a and 4 b , the releasable locking mechanism 24 may be moved along the first support 12 and second support 14 to a second desired position, where the locking arm 52 is released and locks in place ( FIGS. 5 a and 5 b ). The strip door 16 can be moved with minimum force, allowing a user to move the strip door 16 closer to the goods requiring refrigeration, freezing, or heating. In another embodiment, the releasable locking mechanism 24 is moved along the first support 12 pneumatically, according to art known methods, by operation either directly on or around the moveable strip door suspension system 10 , or remotely, e.g., in the cab of a truck by the driver. [0041] Referring now to FIGS. 6 and 7 , in an embodiment of the invention, the releasable locking mechanism 124 clamps onto the first support 112 and is moveable anywhere along the first support 112 between the ends 131 , 132 . The releasable locking mechanism 124 is spring-biassed into frictional engagement with the first support member 112 . In this embodiment, the releasable locking mechanism 124 comprises a brake mechanism 129 , which comprises two rollers 126 a , 126 b and two bump stops 127 a , 127 b . The bump stops 127 a , 127 b comprise a material suitable for frictional engagement with the first support 112 and/or the rollers 126 a , 126 b , such as rubber or plastic. The bump stops 127 a , 127 b are attached to curved pivot arms 180 a , 180 b , which are bolted to base plate 146 by a bolt mechanism 156 a , 156 b (e.g., comprising a nut, a bolt, and a washer). The base plate 146 is bolted to the transverse bar 118 by fasteners 157 a , 157 b (e.g., comprising a nut and a bolt). The rollers 126 a , 126 b are attached to roller axles 125 a , 125 b which are rotatably connected to base plate 146 . A rope 158 is engaged with lever arm 184 . Lever arm 184 comprises ends 186 , 188 , to each of which a cable connector 190 a , 190 b is attached. One end 192 a , 192 b of the cable connector 190 a , 190 b is attached to the lever arm 184 and the other end 194 a , 194 b of the cable connector 190 a , 190 b is attached to a spring and cable anchor plate 196 , which is disposed on pivot arms 180 a , 180 b . One end 200 a , 200 b of a side spring 198 a , 198 b is attached to the spring and cable anchor plate 196 a , 196 b and the other end 202 a , 202 b of the side spring 198 a , 198 b is attached to a spring anchor plate 204 , which is disposed on the base plate 146 . In an embodiment, one end 208 of a center spring 206 is attached to the spring and anchor plate 204 and the other end 210 of the center spring 206 is attached to the lever arm 184 . The center spring 206 is not required but helps to control movement of the lever arm 184 . The releasable locking mechanism 124 is released by pulling rope 158 , which passes through eye bolt 182 , which is bolted to transverse bar 118 . Pulling the rope 158 pulls the lever arm 184 toward the eyebolt 182 , thereby preventing the bump stops 127 a , 127 b from engaging with the first support 112 . Conversely, releasing the rope 158 allows the bump stops 127 a , 127 b to re-engage with the first support 112 when the strip door 128 is placed in the desired location along the first support 112 . The releasable locking mechanism 124 may be used on both ends of the transverse bar 118 , i.e., may be engaged with both a first support 112 and a second support. [0042] In another embodiment, illustrated in FIG. 8 , the bump stops 127 a , 127 b angled such that they engage with both the first support 112 and the rollers 126 a , 126 b when in the locked position. [0043] Although not required to release or move the movable strip door suspension system 10 of the invention along the first support 12 and second supports 14 , as it is for the system disclosed in U.S. Pat. No. 4,639,031, in some circumstances the operator may desire to move the strip door 16 to one side of the container or vehicle 1 . In an embodiment, the strip door 16 can be swung out of the way to simplify loading and unloading, in a similar manner to the “The Swinger” produced by Randall Manufacturing (Elmhurst, Ill.). Referring now to FIG. 9 , the releasable locking mechanism 24 may comprise a hinge mechanism 60 that allows the transverse bar 18 to pivot so that it can be moved to one side of the vehicle. In an embodiment, a pivot hinge mechanism 60 may be provided by making bolt 56 about 0.5 to about 2 inches longer to allow for a nylon sleeve 62 , such as a DryLin®S anodized aluminum shafting or the like, as sold by Igus, Inc. (East Providence, R.I.), to be inserted through transverse bar 18 and fastened with a washer 64 and lock nut 66 . A spanner bushing 68 , such as those sold by Refrigeration Hardware Supply Corp. (Sun Valley, Calif.) or Graphite Metallizing Corp. (Yonkers, N.Y.) will be placed into the hole through which the bolt 56 passes in the transverse bar 18 , allowing the bolt 56 to rotate within the bushing 68 . [0044] Referring now to FIG. 10 , in an embodiment, the first end 38 of the second support 14 is open such that when the roller 26 reaches the first end 38 it travels off the second support 14 and can pivot relative to bolt 56 to be placed along the first side 2 of the vehicle 1 . In another embodiment, an opening can be placed at any point along the length of the second support 14 in order to release and pivot the transverse bar 18 at another location along the second support 14 . [0045] In an embodiment, the strip door 16 is pivoted and then secured to a wall of the container or truck, for example, using a wire form hook 70 such as a bent wire hook, S hook, conveyor hook, wire hold down hook, hanging wire form hook, or the like, such as those sold by Marlin Steel Wire Products (Baltimore, Md.) or Keyspan (Fort Lauderdale, Fla.) or other securing device, such as a tie, snap, bolt, bullet fastener, or the like. [0046] One of the many advantages of the invention is that, compared to the device disclosed in U.S. Pat. No. 4,639,031, the transverse bar 18 of the moveable strip door suspension system 10 is closer to the ceiling 6 , providing more clearance for loading goods, especially given the angle at which they are loaded from the back of a truck using an angled dockboard. The moveable strip door suspension system 10 can also travel the entire length of a vehicle 1 without requiring the operator to disembark from the vehicle. Further, the instant invention also has the added advantage of providing more usable space for cargo, because it does not include the bar locking assembly of the system disclosed in U.S. Pat. No. 4,639,031. INCORPORATION BY REFERENCE [0047] The contents of all cited references (including literature references, patents, patent applications, and websites) that may be cited throughout this application are hereby expressly incorporated by reference. The practice of the present invention will employ, unless otherwise indicated, conventional techniques of strip door manufacturing, which are well known in the art. EQUIVALENTS [0048] The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting of the invention described herein. Scope of the invention is thus indicated by the appended claims rather than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced herein.

The present invention relates to movable barrier systems, such as a strip door suspension systems, that can be repositioned along the length or width of a room, container, or vehicle, for example, that is temperature controlled. The system saves energy, keeps cargo at a constant temperature, and is safe to the operator.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF INVENTION 1. Field of the Invention The invention relates to an elongated ground anchoring arrangement for attachment to a device supporting pole. More specifically, the invention relates to such an elongated ground anchoring arrangement which comprises a hollow member having a screw means at one end thereof, and means for rotating said screw means relative to said cylindrical member. 2. Description of Prior Art Ground anchoring arrangements may be used for anchoring pole mounted devices such as, for example, flags, beach umbrellas, and the like, in the ground. Arrangements for this purpose are known in the art and especially arrangements for anchoring beach umbrellas as illustrated in, for example, European Patent 312,675, Carbone, Apr. 26, 1989, British Patent 1,272,460, Asplin, Apr. 26, 1972, U.S. Pat. No. 4,832,304, Morgulis, May 23, 1989 and U.S. Pat. No. 2,759,486, Pesaturo, Aug. 21, 1956. The '675 patent teaches a ground anchoring arrangement which is in the shape of a stick having a screw means at one end. The screw means is formed integrally with the stick so that, when the stick is rotated, the screw means rotates with the stick. The '460 patent teaches a ground anchoring arrangement which includes a stem, in the form of a hollow cylindrical member, with a screw means fixedly attached to the bottom end of the hollow cyindrical member. Thus, once again, the screw means rotates with the hollow cylindrical member. The arrangement in the '304 patent is similar to the arrangement of the '675 patent in that it consists of a post 12 having a screw means 16 formed at one end thereof. In the '304 patent, as in the '675 patent, the screw means is formed integrally with the post. The '486 patent teaches an arrangement consisting of a pick 13 having a pointed free end. As the pointed end does not have any screw threads, the arrangement in the '486 patent does not include any screw means. SUMMARY OF THE INVENTION It is therefore an object of the invention to provide a novel elongated ground anchoring arrangement for attachment to a device supporting pole. It is a more specific object of the invention to provide such an arrangement which comprises an elongated hollow member, a screw means at one end of the member, and means for rotating said screw means relative to said hollow member. The arrangement is detachably attachable to the device supporting pole at the other end thereof. In accordance with the invention there is provided an elongated ground anchoring arrangement for attachment to a device supporting pole, said device supporting pole having a first end, at which said device is supported, and a second end; said ground anchoring arrangement comprising: an elongated hollow member having a first end and a second end; means for detachably attaching said second end of said device supporting pole to said first end of said elongated hollow member; an elongated rod extending through said hollow member and being rotatably supported therein, said elongated rod having a first end adjacent the first end of said elongated hollow member and a second end adjacent the second end of the said elongated hollow member; handle rotating means; said handle rotating means being attachable to said rod at said first end thereof; screw means mounted at said second end of said rod, externally of said elongated hollow member, for rotation with said rod; wherein, when said handle rotating means is rotated, said rod rotates with said handle rotating means and said screw means rotates with said rod, and, thereby, with said handle rotating means. BRIEF DESCRIPTION OF DRAWINGS The invention will be better understood by an examination of the following description, together with the accompanying drawings, in which: FIG. 1 is a perspective view of the ground anchoring arrangement attached to a beach umbrella; FIG. 2 is a partially cut-away perspective view of the hollow cylindrical member illustrating how the rotating handle is connected thereto to cause rotation of the screw means and also illustrating the rod and bearings in the cylindrical member; FIG. 2A is a cross-section through IIA--IIA of FIG. 2 illustrating the shaped indentation in the plug of the rotating handle; and FIG. 2B is a cross-section through IIB--IIB of FIG. 2. DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1, the elongated ground anchoring arrangement, illustrated generally at 1, is shown detachably attached to a device supporting pole 3 which supports a device 5. In the illustrated embodiment, the device 5 comprises a canopy so that the canopy 5 and the pole 3 together form an umbrella, for example, a beach umbrella. If the device 5 were the cloth of a flag, then the cloth and the poles would together form a flag. The ground anchoring arrangement includes a ground anchor supporting portion 7 and a means 9 for detachably attaching the device supporting pole 3 to the ground anchor supporting portion 7. The means 9 consists of a collar 11 having an open end 12, a handle 13 and a slat-like member 15. The means 9 is disposed at one end of the ground anchoring arrangement. Disposed at the other end thereof is a screw means 17 having a spiral screw thread 19. Turning now to FIG. 2, the ground anchor supporting portion 7 comprises a hollow member 21, in the illustrated embodiment, a hollow cylindrical member, through which extends a rod 23. As can be seen, the diameter of the screw means 17 is greater than the diameter of the hollow cylindrical member 21. As also seen in FIG. 2, the rod 23 is rotatingly supported in the hollow cylindrical member 21 by bearing members 25, 27 and 29. As seen at bearing member 25, each bearing includes an inner race 26 and an external race 28. Disposed between the inner race 26 and the outer race 28 are ball bearings 30. As is well known in the art, the casing is completely filled with at least one row of bearings, and the wall 26 is movable relative to the casing 28. As seen in FIG. 2B, the cross-sectional shape of the rod is non-circular, in the illustrated embodiment, a star-like shape. However, the cross-sectional shape of the rod can be square, rectangular, triangular, pentagonal, oval, etc. It is only necessary, as will be seen below, that the cross-sectional shape of the rod be non-circular. The inner race 26 of the bearing members 25, 27 and 29 will be fixed to the rod so that the inner races 26 of the bearing members 25, 27 and 29 will grip the rod and rotate therewith. The rotation of the inner races 26 and, thereby, the rod 23, are aided by the ball bearings 30 in the bearing members. The walls of the outer race 28 which abut the inner surface of the hollow cylindrical member 21 may be fixedly attached thereto. Also, the bearing members 25, 27 and 29 are fixedly attached, at spaced intervals, to the rod 23. It is also seen that the rotating handle 31 includes an attachment member 33, having an underlying plug 35, and a hand grasping member 37. A bridge 39 joins the attachment member 33 to the hand grasping member 37. As seen in FIG. 2A, the bottom of the plug includes a shaped indentation 41. The shape of the shaped indentation is identical to the cross-sectional shape of the rod 23 so that, when the end of the rod 23 is inserted into the shaped indentation, the rod will be gripped by the rotating handle. The screw means 17 is attached, either fixedly, or detachedly, to the other end of the rod 23. In one way of attaching the screw means 17 to the rod, an opening 43, having a cross-sectional shape which is identical in size and shape to the cross-sectional shape of the rod is provided at the top of the screw means, and the other end of the rod 23 is force-fit into the opening 43. Alternatively, the screw means 17 could be attached by screws or pins to the rod 23, or it could be formed integrally with 23. In operation, to insert the pole 3 into the collar 11, the handle 13 is moved outwardly and upwardly in the direction of arrow A as shown in FIG. 1. The pole 3 is then slid in to the open end of the collar 11. To attach the pole 3 to the ground anchor supporting portion 7, the inner end of the slat-like member 15 could be flat and abut against the outer surface of the pole 3 whereby to attach the pole by frictional engagement. Alternatively, the slat-like member 15 can include a portion which extends beyond the outer diameter of 3 which would include a slot for receiving the extending portion of the slat-like member 15. Alternative arrangements, as is well known in the art, could be used for detachably attaching the device supporting pole 3 to the ground anchor supporting portion 7. In either case, after the free end of the pole 3 is slid into the open end of the collar 11, the handle 13 is returned to the position as illustrated in FIG. 1 so that it will detachably attach the pole 3 to the ground anchor supporting portion 7. To remove the pole 3, the handle 13 is once again moved outwardly and upwardly in the direction of can be slid out of the handle 11. To anchor the ground anchoring arrangement in the ground, the pole 3 is removed as above and the plug 35 of rotating handle 31 is slid into the open end of the collar 11 until the plug 35 grips the end of rod 23. Accordingly, the rod will now rotate with the rotating handle. The screw means is then placed with its point on the surface of the ground into which the arrangement is to be anchored, and the rotating handle is rotated. This will cause the rod 23 and, thereby, the screw means 17 to rotate so that the screw means 17 will dig itself into the ground. The handle will be rotated until such time as the ground anchoring arrangement is firmly anchored in the ground. The rotating handle is then removed, and the device supporting pole can be inserted into the collar to be detachably attached to the ground anchoring arrangement so that the device will be firmly anchored in the ground. To remove the ground anchoring arrangement from the ground, the pole 3 is removed from the collar 11 as above-described and the rotating handle 31 is once again attached to the ground anchoring arrangement. The handle is now rotated in the opposite direction so that the screw means 17 will dig itself out of the ground. Although the rod 23 has been above-described as having a uniform cross-section, it is of course obvious that the rod 23 could have a circular cross-section for most of its length but having either one or two shaped ends. Although a particular embodiment has been illustrated, this was for the purpose of describing, but not limiting, the invention. Various modifications, which will come readily to the mind of one skilled in the art, are within the scope of the invention as defined in the appended claims.

A ground anchoring arrangement for attachment to, for example, the pole of a beach umbrella or the like consists of a hollow cylindrical member having a rod rotatably supported therein. A spiral screw is attached to one end of the rod, and the other end of the rod is grippingly (CANC) attachable to a handle rotator. Thus, when the handle rotator is rotated, the rod rotates, and the spiral screw rotates with it. The point of the screw is placed adjacent to the ground and rotated so that the screw digs itself into the earth to firmly fix the elongated cylinder in the ground.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION The invention relates to a panel set for the formation of athermanous walls, each panel comprising a central core of insulating plastics material between two rigid lateral, substantially sheetlike structures, each panel having edges juxtaposable to the edges of other panels. The invention relates also the the coupling device for connecting panels of the sets together. DESCRIPTION OF THE PRIOR ART Panel sets of the above type are already known, wherein the connection between panels is effected by U-shaped members. In these panel sets, each leg of the U-shaped member penetrates in respective slots in the rigid lateral structures covering the central cores of two adjacent panels. The member extends a considerable way from the junction between panels. This also requires two U-shaped members for each pair of panels, one on each side thereof. Such a system requires the lateral structure to be of a special formation, it being necessary for it to be provided with the slots and the U-shaped members fixed in place by bolts, requiring in turn suitable nuts to receive them. Also, when a panel is to be juxtaposed to a further four panels, one on each edge thereof, the slots must be provided along the panel edges and, as has already been stated, on both sides thereof. It also is not easy to assemble the panels, since they must be held juxtaposed while the U-shaped members are being fitted and it is necessary to work on both sides of the wall being formed with the panels practically at the same time. SUMMARY OF THE INVENTION To overcome the disadvantages of the above and other known embodiments, a panel set of the type described hereinbefore has been devised, characterised fundamentally in that each panel has attached thereto an element of at least one coupling device formed of two mating elements. The coupling device includes, a male element having an outwardly extending active member and a female element having an inwardly extending active member provided with an inlet opening. The mating elements constitute one coupling device on two separate panels. The active female member is adapted to receive insertion of the active male member when the panels are juxtaposed with the female element having an adjustable retractable resilient stop adapted to allow the insertion and retention of the panels together and to force juxtaposed panels closer together. BRIEF DESCRIPTION OF THE DRAWINGS To facilitate the understanding of the foregoing, reference is made hereinafter to the accompanying drawings which, in view of its illustrative nature, should be deemed to be devoid of any limitation with respect to the scope of legal protection being claimed. In the drawings: FIG. 1 is a perspective view of a panel set according to the invention, forming an athermanous wall and abutting a floor S and wall P illustrated in cross section; FIG. 2 is a perspective view on a larger scale of a panel provided with male elements of a coupling device according to one embodiment of the invention; FIG. 3 is a perspective view of part of a panel having a female element of a coupling device according to the invention; FIG. 4 is a partial cross-sectional view showing a male mating element of a coupling device according to the invention insertably connected in a panel having a convex outer edge; FIG. 5 is a partial cross-sectional view showing a female mating element of a coupling device according to the invention insertably connected in a panel having a concave outer edge; FIG. 6 is a plan view, on a larger scale, of the male mating element of the coupling device illustrated in FIG. 4; FIG. 7 is a side view of the male mating element of the coupling device illustrated in FIG. 4; FIG. 8 is a side view of the female mating element of the coupling device illustrated in FIG. 5; FIG. 9 is a plan view of the female mating element of the coupling device illustrated in FIG. 5; FIG. 10 is a cross-sectional view, along the lines X--X of FIG. 9, but with the stem of the male mating element being inserted into the slot of the female mating element the retractable stop in the female element engaging the stem of the male element, the stop spring slightly tensioned, and the convex and concave edges of the panels omitted; FIG. 11 is a cross view, sectional similar to FIG. 10, but illustrating the resilient retractable stop in a position of high spring tension; and FIG. 12 is a side view of the stop which is located in the female element of the coupling device according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to the drawings, particularly FIG. 1, there is illustrated in the first place a set of panels 1 formed by a number of panels juxtaposed edge on, partly forming a wall having athermanous properties. This panel set prevents the passage of heat as a consequence of the properties of the panels to be described hereinafter. In FIG. 1, the athermanous wall formed by the panels is supported on a floor S and a wall P. In a preferred embodiment, and as best seen in FIGS. 2-5 each panel 1 comprises a central core 2 of lightweight, insulating plastics material, preferrably injected foam polyurethane. The central core 2 is sandwiched between two rigid lateral structures 3 which provide the necessary strength and rigidity to the panel and to the wall formed by a set thereof. Preferably the lateral structures 3, which are substantially sheet-like, are formed by metallic sheets covering the front walls of the panel and are provided with perpendicular flanges 4 covering a marginal portion of an edge 5 of the panel. The front dimensions of the panel are as appropriate for each case, although the panels often measure from 30×30 cm to 90×450 cm. The panels are plane, although right-angled panels are contemplated for forming the corners of the athermanous walls. Each panel is provided with at least one element of a coupling device (shown complete in cross-section in FIG. 10) formed by two mating elements, one of which is a male element 6 and the other a female element 7. Nevertheless, with the exception of the smaller sized panels, it is desirable for the same edge 5 of a panel 1 to be provided with a plurality of elements of the same type and the opposite edge to be provided with the other mating elements and the same happens with the edges between said opposite edges. It is, moreover, preferred for the location of such elements to be such that when one panel is juxtaposed at the edge on to another panel, the mating elements mate so that each pair of mating elements, one on one panel and the other on a juxtaposed panel, form a coupling device. Preferbly, the panels which are to form a particular athermanous wall are all the same, so as not to have to select each time the desirable panel to be juxtaposed to another. The above may obviously require an exception in the panels located on two adjacent edges of an athermanous wall, according to the dimensional requirements of the two walls P and floor S and the ceiling which may delimit the extension of the athermanous wall. Moreover, there may be an exception for the panels forming corners. Preferably, the mating elements on the same edge of a panel are disposed symmetrically relative to the ends of the edge itself and also the distance of one terminal element to the extreme end of the edge is half the distance between two consecutive elements. The panel edges 5 having mating elements of the same type are preferably convexly shaped as shown by reference numeral 5a in FIG. 4 with dimensions mating those of concave shaped panel edges 5b shown in FIG. 5 having the opposing mating elements, this provides for a better sealing of the athermanous wall formed by a set of panels. Preferably, and as shown in FIGS. 4 and 5 the convex panel edges 5a are provided with the male mating elements 6 and the concave panel edges 5b have the female mating elements 7. As shown in FIG. 4, the male element 6 is provided with an anchor portion 8 trapped in the central core 2 of the panel 1 and an active male member or stem 9 extending outwardly from the convex panel edge 5a. Preferably, and as seen FIGS. 4, 7 and 10 the stem 9 is provided with bevelled corners 10. The stem 9 is also provided with at least one flank 11 having an inwardly tapering surface, the thickness of the stem reducing in the direction of the anchor portion. FIG. 2 shows a stem 9' of a male mating element 6 as provided with a single flank 11 with the above features, whereas FIGS. 7 and 10 illustrate the stem 9 having two flanks 11 with said features, the flanks being symmetrical in this case about a median plane. The advantages to be derived from this shape of the flanks will be described hereinafter. On the other hand, and as best seen in FIG. 8, the female mating element 7 is provided with a female member or slot 12 with opening 13. The female slot 12 is of a size sufficient to allow the insertion therein of the male stem 9 with a clearance. In the panel 1 as shown in FIG. 5, the female element 7 is trapped in the central core 2 of the panel and the opening 13 is flush with the concave edge 5b of the panel. As best seen from FIGS. 5, 10, and 11, the female element 7 is provided also with a bore 14 which is partly threaded and which is provided with a first open end 15 on the outside of the female element 7 and a second open end 16 in the slot, the second open end 16 being smaller than the first open end 15. In the bore 14 there is housed a resilient retractable stop 17 having a substantially frustoconical end 18 penetrating in the slot 12 through the open end 16. The frustoconical end 18 extends from a disc 19 having a diameter larger than that of the open end 16, whereby it may not penetrate in the slot 12. At the other end of the bore 14 there is the threaded stud 20 screwed in said bore and between the stud 20 and disc 19 there is a spring 21 which, in the illustrated embodiment, is a helical spring tending to force the stop 17 apart from the threaded stud 20. The stud may be manipulated from the outside of the panel 1, to which end it is provided with a slot 22. The bore is made in such a way that when the male stem 9 is inserted in the slot 12, the end 18 of the resilient retractable stop 17 bears against the flank 11, whereby the force of said end on the sloping flank 11 causes a force component in the direction of insertion so as to urge the mating elements together. Therefore, the respective panels are attached by the mating elements. The male and female elements 6 and 7 are made preferably from plastics material, such as nylon, having great rigidity and strength. Moreover, since this material is not a good heat conductor, the possibility of heat losses through such elements is avoided. Nevertheless, the elements 6, 7 may also be metallic, it being necessary, nevertheless, for such metal to be rustfree. In such a case, possible heat losses occur therethrough. Nevertheless, they are small since the transmission surfaces which the elements represent is very small in comparison with the total panel area. If metal elements are used, however, care must be taken that they do not contact the metal sheeting forming the lateral structures 3, by locating therebetween plastics material of the central core 2. In this way undesirable vapour condensation in the areas of the panel surface in contact with the elements 6 and 7, which would be at a different temperature from the rest of the panel, is avoided. From the foregoing, it may be easily appreciated how the panel set is assembled. By simply juxtaposing two panels through the edges provided with mating elements, the stem of the male elements is inserted in the slot of the female elements. During the insertion operation, the bevels 10 of the head of the male stem 9 bear against the frustoconical end 18 of the resilient retractable stop 17, thereby overcoming the force of the spring. The stop 17 retracts and allows complete insertion of the stem 9. After this, the retractable stop 17 advances again and bears against the flank 11, thereby forcing the mating elements together, with the resulting pressure between the panel edges 5 improving the sealing of the panel set. To dismantle the panels, it is sufficient to separate them, whereby the flank 11 forces the stop 17 into the bore 14 against the force of the spring 21. Nevertheless, as stated above, the retractable stop 17 is adjustable by the threaded stud 20. Therefore, if the stud 20 is screwed into the bore 14, it may reach the position illustrated in FIG. 11, wherein the helical spring is fully compressed, thereby preventing recoil of the stop 17 and, therefore, the possibility of separating the panels. In this position of maximum tension of the spring 21, the force of the stop 17 against the flank 11 of the stem 9 is greater and consequently the component forcing the panel edges together is also greater. To dismantle the panels, it is sufficient to slacken off the threaded stud 20 and consequently reduce the pressure of the spring 21, which will allow the male element to be separated from the female element, as mentioned hereinbefore. From the foregoing, the advantages of the panel set and coupling device of the invention will be appreciated. Such advantages may be summed up as follows: ease of assembly by simple juxtapositioning of the panel edges; immediate retaining of the male element stem in the female element slot by means of the retractable stop; tendency of the mating elements to be forced together by the end of the stop bearing against the stem flank; ease of adjustment of the spring pressure, with the possibility of making the stop recoil impossible; simplicity of the operations required for dismantling the panels and, moreover, the athermanous walls formed by the panels have a smooth surface.

A panel set for the formation of athermanous walls, each panel comprising a central core made from insulating plastics material and formed between two rigid sheets. The connection between panels is effected by coupling devices, each of which is formed by two mating elements, the corresponding elements of one coupling device are located on adjacent panels. One of the mating elements is provided with an outwardly active male member and the other mating element is provided with an active female member, adapted to receive the male member. The female mating element has an adjustable retractable resilient stop adapted to allow the insertion and retention of the panels together and to force juxtaposed panels closer together.

You are an expert at summarizing long articles. Proceed to summarize the following text: This is a continuation of copending application Ser. No. 07/355,923 filed on May 23, 1989, now abandoned. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method for repairing post and pre-tensioned concrete structures such as parking ramps whose beams are damaged. More particularly, the method involves the creation of a new post-tensioned beam in a trench where the old tendon and encasing concrete were present. 2. Description of the Related Art Post-tensioned concrete structures depend on the spaced beams of concrete in which a post-tensioned tendon is positioned. Pre-tensioned structures apply tension to the tendon prior to the concrete pour. With time, salt and other detrimental chemicals tend to break down the concrete and contacts the tendons. Damage to the tendons may severely weaken the integrity of the post-tensioned structure requiring repair. In some cases damage is so severe that the entire deck must be replaced which is extremely expensive and effectively puts the structure out of use until repairs are completed. An alternative method of repairing such post-tensioned structures is described in Reigstad et al, U.S. Pat. No. 4,574,545, the disclosure of which is incorporated herein by reference. In Reigstad, concrete is repaired either by pulling the individual strands of the steel tendon out and replacing the tendon after reaming the bore, or by releasing tension in the tendon and exposing the tendon from above at its ends and beneath through its central span. After the tendon is removed, new concrete is applied to cover the new tendon. Plywood must be applied to the underside of the slab and be supported overhead by shoring from the slab below as a form for the new concrete placed on the ceiling of the slab. The Reigstad process involves the use of jackhammers and overhead jackhammer stands from below which remove concrete from the ceiling. The method necessitates the closing of both the floor being worked on and the lower floor where jackhammers must be used and forming must be supported by shoring. The Reigstad process leaves much more than half of the original concrete untouched around the tendon being replaced, for fear that excessive removal of concrete e will cause slab deformation. Thus, a large amount of concrete above the tendon, which may have chloride ions present, is left in place. The new tendon in the Reigstad process is coated to prevent corrosion by this and other sources of chloride ions. The Reigstad process is particularly inappropriate when the slab being repaired functions as a ceiling for office or retail store space, since such spaces would need to be closed down during the repair process. Unfortunately, complete slab replacement or complete removal of the post-tensioned beams also require the shutdown of any underlying businesses. Reigstad describes repair methods in which the entire beam is removed by cutting completely through the slab. This method was characterized as being unworkable. The Reigstad process had been known and practiced in the United States since at least as early as 1970. SUMMARY OF THE INVENTION The present invention provides a method in which the deteriorated beam, complete with tendon and surrounding concrete, is replaced to form a new beam. Enough concrete is left below the original tendon during the process to provide a form for positioning the new tendon and concrete. The concrete with the highest chloride ion concentration is completely removed in the process. The old concrete under the new beams thus formed functions aesthetically and contributes little, if any, structural strength. The method of the invention involves the formation of a trench down to the original tendon to completely expose the tendon from above, except adjacent the end anchors. The tension in the tendon is maintained until the concrete is substantially removed, which greatly aids the removal of old concrete because of the upward force of the tendon. Also, the tendon under tension acts as a shield to ensure that a jackhammer does not accidentally break through the ceiling of the lower floor. The exposed tendon is then cut to release any further tension which has not been relieved by the removal of overlying concrete and is removed. The remaining concrete above the ends adjacent the anchors is removed and a profile groove for the new tendon is cut. The bonding surfaces of the entire trench to which the new beam must be attached is then prepared. The trench is then built up if needed to present the desired tendon profile grade. Tendon profile rebar retainers are then positioned across the trench to connect the opposing concrete surfaces, prevent spalling, facilitate bonding of the new concrete and retain the position of the new tendon therebelow. The rebar retainers consist of coated rebar which are placed in bores drilled into the trench sides. The rebar are then bonded in place with epoxy or the like and are bent to the desired elevation. Generally, the rebar retainers are placed from the midpoint of the new beam toward the anchors. The retainers are usually to be used during the concave drape region of the new tendon. The new tendon (preferably coated or sheathed) is woven into the tendon profile groove. It is then attached to new end anchors which preferably include the addition of coated bars anchored into the old concrete perpendicular to the new tendon in a manner similar to that used in installing the rebar retainers. Angled hook bars are also preferably used in the anchorage and are placed parallel with the tendon extending from the new anchor. In order to improve bonding and corrosion resistance the entire bonding surface of the trench is preferably coated with an epoxy compound, after which concrete is poured. After the new concrete has reached the required strength the new beam is post-tensioned to the specified design load. Protective caps are then placed over the tendon ends at the anchors. The end anchor region pocket is then filled with concrete to complete the new post-tensioned beam. BRIEF DESCRIPTION OF THE DRAWINGS The detailed description of the invention including its preferred embodiment is hereinafter described with specific reference being made to the drawings in which: FIG. 1 is a perspective view of a portion of a typical post-tensioned slab showing existing tendons and temperature tendons in phantom; FIG. 2 is a perspective view similar to FIG. 1 in which the old concrete has been removed to form a trench for the new beam; FIG. 3 is a cross-sectional view through lines 3--3 of FIG. 2 showing the trench profile for the new beam; FIG. 4 is a cross-sectional view through lines 4--4 of FIG. 3 showing the cuts made to expose the tendon at its deepest point in the old slab; FIG. 5 is a sectional view similar to FIG. 4 showing an alternate method to expose the tendon; FIG. 6 is a perspective view of the slab and cut trench to show the position of the anchors and new tendons; FIG. 7 is a sectional view taken along line 7--7 in FIG. 6 showing the tendon profile rebar retainers relative to the new untensioned tendons; FIG. 8 is a top view of the trench showing the rebar, new tendons and anchor plates; FIG. 9 is an illustration of one form in which the new beam may be made; FIG. 10 is an alternative design to the new beam shown in FIG. 9; FIG. 11 is an illustration of a means to repair breakthrough regions showing the suspended form in phantom; and FIG. 12 is an illustration of an alternative means to repair breakthrough regions. DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to the drawings in which like reference numerals are used throughout to designate identical or corresponding elements, the process will be seen as involving a slab 10 supported upon beams 12. Slab 10 is a post-tensioned structure having primary tendons 20 extending in one direction and temperature tendons 24 (which may also be post-tensioned) extending perpendicular to the primary tendons 20. Although the description of the invention will refer to repairing post-tensioned structures, it is also applicable to repair of pre-tensioned structures. In these cases, the pre-tensioned tendon is replaced with a post-tensioned tendon in a new beam. After testing has been conducted to determine which tendons need replacement, the tendons are located by a metal detector. Preferably, the tendons are located with a Rebar Hunter® brand instrument from Matcor, Inc. of Doylestown, PA. Such an instrument locates metal in concrete and displays information on depth. The ends of the tendons 20 to be replaced are exposed by jackhammer to confirm their profile, course and location. Saw cuts are then formed on both sides of the tendon to establish a trench about six (6) to seven (7) inches in width. The saw depth is set to ensure that any temperature tendons 24 are not cut. Usually, this entails a saw depth of two (2) inches or less. It is preferable to make the saw cuts only about four (4) to six (6) feet in length. Opening this short length of trench allows one to follow the course of the old tendons. Existing tendons may not have been installed in a straight line or at original design depth or elevation. After the trench has been outlined by the parallel saw cuts, the concrete between the saw cuts is removed until the top of the old tendon is exposed. Removal of concrete may be made by the use of jackhammers. Preferably, a heavier jackhammer is utilized initially to remove the first several inches of concrete, followed by a lighter weight chipping jackhammer. The remaining tension in the tendon assists the removal of concrete by imparting an upward force to the concrete chunks in the trench. Also, the uncut tendon assists in preventing the jackhammers from cutting completely through the old concrete. The process of concrete removal continues with short lengths of saw cuts and removal of concrete until all but about five (5) feet on both ends of the tendon are exposed. At that time, any remaining tension in the tendon is released by cutting the tendon which is usually cut with a torch. The removal of concrete may release some tension on the tendon. Tension in the tendon is utilized to assist the concrete removal process. Also, release of tension from stressed tendons by cutting off button heads in end anchors 28 is not preferred, since shim plates may let go. The tendon thus exposed is then removed from the trench. Preferably, the tendon is cut between temperature tendons and pulled in sections from the trench. The removal of concrete down to the top of the old tendon preserves the old tendon's profile groove for installation of the new beam. After the remaining concrete at the tendon ends is removed, a vee-shaped profile groove is formed at the bottom of the trench for placement of the new tendon. The vee-shaped groove is formed by saw cutting to the bottom of the old tendon profile groove. It is sawn to the width needed for the number of new tendons to be installed. Jackhammers with (1-1/2 inch wide) chisel bits may be used to remove concrete between the saw cuts to define the vee-shaped groove 30. All rubble and debris is then removed from the trench. Enough concrete remains to function as a form for the new concrete pour which will form the new beam. Structurally, this retained concrete contributes little strength to the new beam formed. Any breakthrough regions 48 caused by the concrete removal step are repaired. Breakthroughs may occur due to poor placement of the original tendon which was too close to the bottom of the concrete slab. With reference to FIGS. 11 and 12, a repair method is shown in which a plywood form 50 is held beneath the hole 48 by cable 52 which may be attached to a piece of rebar 54. After the concrete is cured, the cable may be cut to remove the rebar 54. Alternatively as shown in FIG. 12, the rebar 54 may be embedded beneath the surface of the beam by securing one or both ends to walls of the old concrete trench. The entire trench is then prepared for formation of the new beam. All bonding surfaces of the trench are cleared of loose concrete, aggregate or other deletorious materials. Sand or water blasting are suitable cleaning methods. The trench is then vacuumed or blown out. The tendon profile groove for the new beam is then built up, if needed, in areas where the old tendon was originally too deep or the trench was over-excavated. As shown in the drawings, the tendon's profile drape creates a concave area in relation to the horizontal plane of the slab surface over a significant length of the tendon. In those areas, the tendons must be retained below the horizontal midpoint of the slab to ensure that the post-tension of the tendon provides the required structural lift and support the beam is to provide. To accomplish this, prevent spalling of concrete, and facilitate the bonding of the new beam to the existing slab a plurality of tendon profile rebar retainers 60 are utilized. Rebar retainers 60, as best shown in FIGS. 6 and 7, are placed into angled drill holes 70 in walls 74, 76 of the trench. The rebar retainers 60 are preferably epoxy coated rebar. The drill holes 70 should be close to the bottom of the trench and must be cleared of debris. The rebar retainers 70 are then epoxied in position. The rebar retainers are needed from the midpoint between beams 12 and may be placed at one (1) to two (2) foot centers. The portions of the tendon's concave profile drape which will require retention below the horizontal midpoint of the slab may be about fifteen (15) feet. The length of the concave profile drape and number of rebar retainers 60 required may vary depending on the application. New tendons 80 are woven into the profile groove positioned under the rebar retainers 60 and temperature tendons 24. Preferably, the tendons are coated or sheathed, such as with polyurethane, for corrosion resistance. Suitable tendons include 1/2 inch, low relaxation 7-wire stress-relieved strand in accordance with ASTM A416. Such tendons have a breaking load of about 42,000 pounds. New end anchors 90 are constructed as best shown in FIG. 6. In addition to the standard anchor plates 90, it is preferable to include reinforcing bars 92 to strengthen the anchorage. Standard anchor plates are available from many sources, including VSL Corp. of Los Gatos, California. A suitable anchor plate 90 is described in U.S. Pat. No. 4,616,458, the disclosure of which is incorporated herein by reference. The anchor plate 90 is preferably attached to a plurality of bars 92 perpendicular to the tendon. The bars 92 are anchored to the walls 74, 76 of the trench in much the same manner as the rebar retainer. The bars 92 are epoxied into holes in walls 74, 76 of the trench. Hook bars 94 are positioned over the anchor plate 90 so as to run parallel with the tendons as shown. Hook bars 94 may be on the order of about three (3) feet in length. Both bar 92 and hook bars 94 are preferably coated with epoxy or other corrosion resistant material. The ends of the hook bars are preferably inserted into drill holes in the concrete beam and epoxied in place. The entire surface of the trench is then preferably coated with an epoxy compound to improve the adherence of the new beam to the original slab. A suitable epoxy is the high modulus, high strength epoxy bonding/grouting adhesive Sikadur® 32 from Sika Corp. of Lyndhurst, New Jersey. The epoxy may also be used to set the rebar retainers. Concrete is then poured into the trench to complete the new beam 100. The new beam 100 is shown in FIGS. 9 and 10. It may range from a single rectangular box to the version of FIG. 10. Preferably, the upper surface is coated with a concrete curing compound. The concrete may include a plasticizing, water-reducing and extended slump-life concrete admixture such as Sikament® 320 from Sika Corp. of Lyndhurst, New Jersey. Such admixtures are usually added at the ratio of 6-18 fluid ounces per sack of concrete. The concrete may be a Type III Portland mix such as Minnesota Department of Transportation specification 3U18, available from Twin City Concrete, Minnesota. After the concrete has reached a strength of at least above 5,000 pounds per square inch, the tendons are post-tensioned to the specified design load, which is typically in the range of 27-35 kips. Any cable grease on the cable should not be removed since it makes for easier installation of a cap and since it adds corrosion protection. A protective cap may be placed on the protruding tendon beyond the anchor plate. The stressing pocket area is then filled with a non-shrink concrete to complete the beam replacement. While this invention may be embodied in many different forms, there are shown in the drawings and described in detail herein specific preferred embodiments of the invention. The present disclosure is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated. This completes the description of the preferred and alternate embodiments of the invention. Those skilled in the art may recognize other equivalents to the specific embodiment described herein which equivalents are intended to be encompassed by the claims attached hereto.

A method for repairing damaged post-tensioned or pre-tensioned concrete structures by removing steel tendons and forming new concrete post-tensioned beams in their place. The method includes the steps of removing concrete above the tendon to be replaced while leaving concrete under the tendon, releasing any remaining tension in the tendon and removing same, preparing the concrete surface for a pour of new concrete, installing rebars perpendicular to the tendon, installing new tendon and anchorages, pouring concrete and post-tensioning the new tendon in the new beam formed.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND [0001] The present invention relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides a system and method for damping fluid pressure waves in a subterranean well. [0002] It is well known that detonation of perforating guns in a well can cause damage to equipment in the well. It has generally been considered that this damage is due primarily to forces generated by detonation of the perforating guns. These forces are transmitted to other equipment via a tubing string in which the perforating guns and the other equipment are interconnected. [0003] For this reason, previous attempts to protect the equipment from damage have focused on isolating the equipment from the forces generated by the perforating guns' detonation. For example, shock absorbers have been interconnected in the tubing string between the equipment and the perforating guns. As another example, methods have been developed wherein the equipment is physically separated from the perforating guns prior to detonating the perforating guns. [0004] However, damage to equipment may actually, or additionally, be caused by pressure waves generated by the perforating guns when they are detonated. Shock absorbers do not isolate the equipment from damage due to these pressure waves. Furthermore, separating the equipment from the perforating guns may not be necessary if damage to the equipment may be prevented, or at least substantially reduced, by damping the pressure waves. [0005] Damping pressure waves may also be beneficial in other operations performed in wells. For example, fracturing operations, propellant-driven packer setting, casing repair, etc. SUMMARY [0006] In carrying out the principles of the present invention, in accordance with embodiments thereof, a system and method of damping fluid pressure waves in a subterranean well is provided. In a described embodiment, pressure waves are damped by positioning a dampener in the well during a perforating operation. The dampener may attenuate the pressure waves by absorbing the pressure waves, flowing the pressure waves through viscously damping material, generating complementary pressure waves, changing a material phase, or by a combination of these methods. [0007] In one aspect of the invention, a perforating system for a subterranean well is provided. The system includes a perforating gun positioned in the well, and a fluid pressure wave dampener positioned in the well, The dampener damps pressure waves generated by detonation of the perforating gun. [0008] In another aspect of the invention, a method of damping pressure waves in a subterranean well is provided. The method includes the steps of: providing a fluid pressure wave dampener; positioning the dampener in the well; generating the pressure waves in the well; and damping the pressure waves with the dampener. [0009] These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative embodiments of the invention hereinbelow and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0010] [0010]FIG. 1 is a schematic cross-sectional view of a first method embodying principles of the present invention; [0011] [0011]FIG. 2 is a perspective view of a first pressure wave dampener embodying principles of the invention; [0012] [0012]FIG. 3 is a schematic cross-sectional view of the first pressure wave dampener; [0013] [0013]FIG. 4 is a schematic cross-sectional view of a first alternate construction of the first pressure wave dampener; [0014] [0014]FIG. 5 is a schematic cross-sectional view of a second alternate construction of the first pressure wave dampener; [0015] [0015]FIG. 6 is a schematic cross-sectional view of a second pressure wave dampener embodying principles of the invention; [0016] [0016]FIG. 7 is a schematic cross-sectional view of a third pressure wave dampener embodying principles of the invention; [0017] [0017]FIG. 8 is a schematic cross-sectional view of a fourth pressure wave dampener embodying principles of the invention; [0018] [0018]FIG. 9 is a perspective view of a fifth pressure wave dampener embodying principles of the invention; [0019] [0019]FIG. 10 is a side elevational view of the fifth pressure wave dampener. [0020] [0020]FIG. 11 is a schematic cross-sectional view of a second method embodying principles of the present invention; and [0021] [0021]FIG. 12 is a schematic cross-sectional view of a third method embodying principles of the present invention. DETAILED DESCRIPTION [0022] Representatively illustrated in FIG. 1 is a method 10 which embodies principles of the present invention. In the following description of the method 10 and other apparatus and methods described herein, directional terms, such as “above”, “below”, “upper”, “lower”, etc., are used only for convenience in referring to the accompanying drawings. Additionally, it is to be understood that the various embodiments of the present invention described herein may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., and in various configurations, without departing from the principles of the present invention. [0023] In the method 10 , a tubing string 12 is conveyed into a wellbore 14 . The tubing string 12 includes a packer 16 , a production valve 18 , a perforating gun 20 and a firing head 22 . The packer 16 is set in casing 24 lining the wellbore 14 , and the perforating gun 20 is detonated to form perforations 26 extending outwardly through the casing. [0024] A bridge plug or sump packer 28 may be set in the casing 24 below the perforating gun 20 prior to, or in conjunction with, running the tubing string 12 into the well. Alternatively, the wellbore 14 below the perforating gun 20 may be open to the casing shoe (not shown) or the bottom of the well. [0025] Any number of perforating guns, firing heads, etc. may be used in the method 10 in keeping with the principles of the invention. It should also be clearly understood that, although the method 10 as described herein is a method wherein a perforating operation is performed, the principles of the invention are not limited to any particular details of the method described herein, and are not limited to perforating operations at all. The principles of the invention have application in any operation wherein it is desired to dampen pressure waves in a well, for example, formation fracturing operations, casing repair operations, packer setting, etc., each of which may generate damaging pressure waves in the well. [0026] It has been found that pressure waves generated by detonation of a perforating gun, such as the perforating gun 20 , travel through fluid in the well and create pressure differentials across equipment in the well. For example, a pressure wave generated at the perforating gun 20 will travel both upward and downward in the wellbore 14 . Upwardly traveling pressure waves will reflect off of the packer 16 and begin to travel downward. Downwardly traveling pressure waves will reflect off of the plug 28 , or the bottom of the well, and begin to travel upward. [0027] Where coinciding in-phase, or approximately in-phase, pressure waves are at their maximum pressure amplitude, a relatively high pressure is experienced by the tubing string 12 . This condition is believed to occur typically just below the packer 16 , at the top end of the perforating gun 20 , and just above the plug 28 or bottom of the well. [0028] Where coinciding in-phase, or approximately in-phase, pressure waves are at their minimum pressure amplitude, a relatively low pressure is experienced by the tubing string 12 . This condition is believed to occur typically one-fourth wavelength above the plug 28 or bottom of the well, one-fourth of the distance from the top end of the guns to the plug or bottom of the well, and one-fourth of the distance from the packer to the plug or bottom of the well. [0029] When the relatively high and low pressures are applied to the tubing string 12 , the differential between the high and low pressures produces very high stresses in the tubing string, leading to significant damage to the equipment interconnected therein. Therefore, in the method 10 , a pressure wave dampener 30 is interconnected in the tubing string 12 . The dampener 30 acts to reduce the amplitude of the pressure waves generated in the well, thereby decreasing the pressure differential produced across the tubing string 12 . [0030] The dampener 30 may operate by absorbing or viscously damping the pressure waves, or by generating a resonant frequency which complements that of the pressure waves in the well. If the dampener 30 operates by absorbing or viscously damping the pressure waves, it should preferably be positioned at one or more locations where the highest fluid velocity is found, which is where the pressure wave amplitude is at its minimum, as described above. If the dampener 30 operates by generating complementary pressure waves, it should preferably be positioned at one or more locations where the lowest fluid velocity is found, which is where the pressure wave amplitude is at its maximum, as described above. [0031] Referring additionally now to FIG. 2, a pressure wave dampener 32 is representatively illustrated. The dampener 32 may be used for the dampener 30 in the method 10 . However, it should be understood that the dampener 32 may be used in other methods, without departing from the principles of the invention. [0032] The dampener 32 includes a pressure wave absorbent material 34 enclosed in a protective outer cage 36 . The pressure wave absorbent material 34 is preferably a porous or fibrous material, such as steel wool, mineral wool, open-cell foam, etc. The material 34 viscously dampens pressure waves by forcing the fluid to flow through its many small passages in order to transmit pressure therethrough. [0033] Referring additionally now to FIG. 3, a cross-sectional view of the dampener 32 is representatively illustrated. In this view it may be seen that a hollow cavity 38 is formed within the material 34 . The cavity 38 is hollow in that it has none of the material 34 therein. The size (height, diameter, volume, etc.), shape and position of the cavity 38 may be adjusted as desired to “tune” the dampener 32 so that it attenuates a particular pressure wave frequency. For example, it may be found through experimentation or practical observation that a particular frequency band causes a substantial portion of damage to the tubular string 12 . In that case, the size of the cavity 38 , or other parts of the dampener 32 , may be adjusted to target that frequency band. [0034] Note that interior and exterior surfaces 37 , 39 of the material 34 may be smooth, and/or may be provided with scallops, crenellations, fingers, peaks and valleys, other recesses, other projections etc., as depicted in FIG. 3. These various surfaces may be used to target a particular pressure wave frequency and/or increase the overall attenuation provided by the dampener 32 . [0035] Referring additionally now to FIG. 4, another alternate construction of the dampener 32 is representatively illustrated. In this construction, a flow passage 40 of the tubing string 12 extends axially through the dampener 32 . The material 34 is isolated from the flow passage 40 . This construction enables production flow, equipment, circulation, etc., to pass through the dampener 32 . [0036] An annular cavity 42 may be provided in the material 34 . As with the cavity 38 described above, the size, shape and position of this cavity 42 may be adjusted as desired to target a particular frequency band for damping. As with the construction depicted in FIG. 3, the interior and/or exterior surfaces 37 , 39 of the material 34 may be smooth, and/or may be provided with scallops, crenellations, fingers, peaks and valleys, recesses, projections, etc. [0037] Referring additionally now to FIG. 5, another alternate construction of the dampener 32 is representatively illustrated. In this alternate construction, the material 34 is isolated from the cavity 38 by a flexible impermeable membrane 44 . The membrane 44 could, for example, be made of an elastomer material, such as rubber, nitrile, viton, etc., or it could be made of a non-elastomer. [0038] Preferably, the cavity 38 is filled with a liquid, such as silicone oil, etc. Alternatively, the cavity 38 could be in fluid communication with the wellbore 14 external to the dampener 32 , so that well fluid is in the cavity. Thus, the cavity 38 could be pressure balanced with the wellbore 14 surrounding the dampener 32 . Again, the size, shape and position of the cavity 38 may be adjusted to target a particular pressure wave frequency band. As with the construction depicted in FIG. 3, the interior and/or exterior surfaces 37 , 39 of the material 34 may be smooth, and/or may be provided with scallops, crenellations, fingers, peaks and valleys, recesses, projections, etc. [0039] Referring additionally now to FIG. 6, another pressure wave dampener 46 is representatively illustrated. The dampener 46 may be used for the dampener 30 in the method 10 . However, it should be understood that the dampener 46 may be used in other methods, without departing from the principles of the invention. [0040] The dampener 46 includes an enclosed volume 48 within a housing 50 having multiple openings 52 through a sidewall thereof. Flowpaths 54 provide fluid communication between the volume 48 and the openings 52 . When the dampener 46 is positioned in a well, such as that depicted in FIG. 1, the openings 52 and flowpaths 54 provide fluid communication between the volume 48 and the wellbore 14 external to the dampener. [0041] The dampener 46 is similar in many respects to a device known to those skilled in the acoustic damping art as a Helmholtz resonator. A Helmholtz resonator cancels sound waves by generating sound waves out of phase. The sound waves enter the resonator openings, travel through the flowpaths to the volume, and are reflected back out of phase. [0042] The Helmholtz resonator is particularly useful in targeting a relatively narrow frequency band of sound waves at which it resonates. The approximate resonant frequency of a Helmholtz resonator is given by the following formula: f=c/2π(A/LV) 1/2 , in which c is the speed of sound, A is the area of the openings, L is the length of the flowpaths and V is the internal volume. It is believed that the same formula would approximate the resonant frequency of the dampener 46 depicted in FIG. 6. [0043] Several modifications may be made to the dampener 46 to increase the frequency band at which it is effective to dampen the pressure waves. For example, the flowpaths 54 may be perforated as shown at 56 to thereby provide multiple flowpath lengths between the openings 52 and the volume 48 , and to add viscous damping. As another example, a pressure wave absorbent material 58 may be positioned in the volume 48 to add viscous damping. [0044] Referring additionally now to FIG. 7, another pressure wave dampener 60 is representatively illustrated. The dampener 60 may be used for the dampener 30 in the method 10 . However, it should be understood that the dampener 60 may be used in other methods, without departing from the principles of the invention. [0045] The dampener 60 is somewhat similar to the dampener 46 described above, in that it includes an internal chamber 62 and multiple openings 64 providing fluid communication between the internal chamber and the well exterior to the dampener. The openings 64 are formed through a sidewall 66 separating the chamber 62 from the well exterior to the dampener 60 . However, the dampener 60 does not have elongated flowpaths between the openings 64 and the chamber 62 . [0046] Preferably, the openings 64 have a combined area which is approximately 30% to 60% of the surface area of the sidewall 66 . This configuration uses viscous damping of the pressure waves traveling through the sidewall 66 to damp the pressure waves. By adjusting the size, shape, number and positioning of the openings 64 , and the size and shape of the chamber 62 , the frequency band at which maximum pressure wave attenuation is achieved may be altered as desired. In addition, pressure wave absorbent material 68 may be positioned in the chamber 62 . [0047] Referring additionally now to FIG. 8, another pressure wave dampener 70 is representatively illustrated. The dampener 70 may be used for the dampener 30 in the method 10 , except that the dampener 70 is combined with a perforating gun 72 . Of course, the dampener 70 may be used in other methods, without departing from the principles of the invention. [0048] An internal volume 74 is formed in the gun 72 . Flowpaths 76 extend into the volume 74 from a sidewall 78 of the gun 72 . It will be readily appreciated that, when the gun 72 is detonated, openings (not shown) will be formed by perforators 80 (explosive shaped charges) through the sidewall 78 . At that point, the gun 72 will be very similar to the dampener 46 depicted in FIG. 6, in that the openings and flowpaths 76 will provide fluid communication between the volume 74 and the wellbore external to the dampener 70 . [0049] Referring additionally now to FIG. 9, another pressure wave dampener 82 is representatively illustrated. The dampener 82 may be used for the dampener 30 in the method 10 . However, it should be understood that the dampener 82 may be used in other methods, without departing from the principles of the invention. [0050] The dampener 82 acts by viscously damping the pressure waves traveling through an annulus 84 formed between the wellbore 14 and the tubing string 12 . The dampener 82 includes whiskers or fibers 86 extending outwardly from a central axially extending mandrel 88 . Preferably, the fibers 86 contact the wellbore 14 , in which case the fibers may be deployed after the dampener 82 is conveyed into the well, for example, by removing a shroud (not shown) initially constraining the fibers. Removal of the shroud enables the fibers 86 to extend outward into contact with the wellbore 14 . [0051] The fibers 86 may be made of any material, including steel, other metals, plastics, composites, etc. The fibers 86 may be made of a phase change alloy, in which case the pressure waves traveling through the fibers induce strain in the fibers, which causes the fibers to change phase and thereby absorb increased energy from the pressure waves. [0052] In FIG. 10, the dampener 82 is depicted from a side view apart from the wellbore 14 . In this view it may be clearly seen that the fibers 86 have a density which increases in the downward direction. It will be readily appreciated that the fibers 86 also have a density which increases in the radially inward direction as well. This varied density aids in impedance matching to the fluid in the well, decreasing the amplitude of pressure waves reflected from the dampener 82 . [0053] Referring additionally now to FIG. 11, another method 90 embodying principles of the invention is representatively illustrated. Elements depicted in FIG. 11 which are similar to elements previously described are indicated in FIG. 11 using the same reference numbers. [0054] In the method 90 , the perforating gun 20 is separated from the equipment, such as a well screen 92 and packer 16 , for which protection is desired. For example, the perforating gun 20 may be separately conveyed into the wellbore 14 (such as by wireline or tubing conveyance) and anchored therein using a gun hanger 94 . Alternatively, the perforating gun 20 , hanger 94 and the remainder of a tubing string 96 may be conveyed together into the wellbore 14 , the hanger 94 set in the casing 24 , the tubing string 96 above the hanger disconnected and raised in the wellbore 14 , and the packer 16 set in the casing to anchor the tubing string. [0055] Although the packer 16 and screen 92 are physically separated from the perforating gun 20 , they are still subject to damage due to pressure waves generated by detonation of the perforating gun 20 . Any of the dampeners 32 , 46 , 60 , 70 , 82 described above may be used in the method 90 to dampen these pressure waves. However, the method 90 uses another pressure wave dampener 98 . [0056] The dampener 98 is constructed with a relatively thin outer wall or shroud 100 which is intentionally designed to deform when it encounters the pressure waves generated by the perforating gun 20 . This deformation of the shroud 100 absorbs energy from the pressure waves. The shroud 100 may deform plastically and/or elastically in response to the pressure waves. It is preferred that the shroud 100 deform plastically in order to absorb a greater amount of energy. [0057] Referring additionally now to FIG. 12, another method 102 embodying principles of the invention is representatively illustrated. Elements depicted in FIG. 12 which are similar to elements previously described are indicated in FIG. 12 using the same reference numbers. [0058] The method 102 is substantially similar to the method 90 described above. However, instead of the dampener 98 , the method 102 uses a pressure wave dampener 104 which has whiskers or fibers 106 extending inwardly from an outer shroud 108 . The fibers 106 may be similar to the fibers 86 described above. [0059] The dampener 104 viscously dampens the pressure waves as they travel through the fibers 106 . This reduces the transmission and reflection of the pressure waves in the wellbore 14 , thereby protecting the packer 16 and screen 92 from damage due to pressure differentials created by the pressure waves. [0060] Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments of the invention, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to these specific embodiments, and such changes are contemplated by the principles of the present invention. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims and their equivalents.

A system and method of damping fluid pressure waves in a subterranean well. In a described embodiment, pressure waves are damped by positioning a dampener in the well during a perforating operation. The dampener may attenuate the pressure waves by absorbing the pressure waves, flowing the pressure waves through viscously damping material, generating complementary pressure waves, changing a material phase, or by a combination of these methods.

You are an expert at summarizing long articles. Proceed to summarize the following text: TECHNICAL FIELD This invention relates to a system and method for automatically controlling the movement of an arm on a work machine. BACKGROUND Work machines are often equipped with a work machine arm capable of performing any number of tasks. For example, a work machine such as a backhoe or an excavator may include a digging work machine arm. Likewise, a work machine such as a forklift or a telescopic material handler may include a work machine arm for lifting and carrying objects. Other work machines may include work machine arms that are adapted to support vibratory compactors or other equipment. Because controlling a work machine arm is often a complex process, an inexperienced operator may have difficulty moving an element of the work machine arm, such as a work implement, along a desired path. To simplify the coordination required to accomplish this, some work machines are provided with a single input device that controls the movement of all the components of the work machine arm. Use of a single input device may simplify the operation of the work machine arm and reduce operator fatigue. U.S. Pat. No. 6,374,153 to Brandt et al. discloses an apparatus and method for providing coordinated control to a telescopic material handler. Often, a material handler is used to raise a pallet in a vertical direction. The coordinating apparatus of the '153 patent enables an operator to more easily control the material handler arm so that it moves along the vertical path by simultaneously changing both the length and the angle of the boom. The '153 patent discloses a control system that calculates a compensating error that may develop when one hydraulic cylinder does not receive the necessary hydraulic fluid flow due to the demand of flow from another cylinder. At times, it may be desirable to move different components of the work machine arm in an order of priority that can be adapted to the needs of a specific work site. For example, when a work machine arm is used to dig in an area adjacent a standing structure, a bucket on the work machine arm must be extended so that the bucket edge approaches the wall before the back of the bucket. In another example, the life of a specific, expensive component of the work machine arm may be prolonged by using it only when necessary. Current work machines having systems for coordinated movement do not provide for prioritizing the movement of different components of the work machine arm. The present invention is directed to overcoming one or more of the disadvantages of the prior art. SUMMARY OF THE INVENTION In one aspect, a method of controlling the movement of a work machine arm having a series of hydraulic cylinders operatively engaged with the work machine arm is disclosed. The method includes receiving a signal from an input device to change the position of the work machine arm and determining an extension amount of one or more of the series of hydraulic cylinders. The extension amount of one or more of the series of hydraulic cylinders is changed to effect the change in the position of the work machine arm. The changes in the extension amount of the one or more of the series of hydraulic cylinders are ordered based on a pre-selected priority of movement. In another aspect, a system for controlling the movement of a work machine arm having a series of hydraulic cylinders operatively engaged with the work machine arm is disclosed. The system includes an input device operable to generate a signal to change the position of the work machine arm and at least one sensor associated with one or more of the series of hydraulic cylinders for determining an extension amount of the one or more of the series of hydraulic cylinders. A control module is adapted to receive the signal from the input device and to change the extension amount of one or more of the series of hydraulic cylinders to affect the change in the position of the work machine arm. The changes in the extension amount of the one or more of the series of hydraulic cylinders are ordered based on a pre-selected priority of movement. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic illustration of a portion of a work machine suited for use with the present invention. FIG. 2 is a block diagram illustrating an exemplary controller for operating a work machine arm. FIG. 3 is a flow chart showing an exemplary method for controlling a work machine arm using a pre-selected priority of movement. FIG. 4 is a flow chart showing an exemplary method of extending a work machine arm using a pre-selected priority of movement. FIG. 5 is a flow chart showing an exemplary method of retracting a work machine arm using a pre-selected priority of movement. DETAILED DESCRIPTION FIG. 1 is a work machine 100 shown in relevant portion as a backhoe loader, that may be used for a wide variety of earth-working and construction applications. Although the work machine 100 is shown as a backhoe loader, it is noted that other types of work machines 100 having multiple linkages, e.g., excavators, front shovels, material handlers, and the like, may be used with embodiments of the disclosed system. The work machine 100 includes a work machine arm 102 having a boom 104 , a stick 106 , an extendable stick (E-stick) 108 , and a work implement 110 , all controllably attached to the work machine 100 . A boom cylinder 112 extends from the boom 104 to a body of the work machine 100 and is adapted to pivotally move the boom 104 with respect to the body of the work machine 100 . A stick cylinder 114 extends between the stick 106 and the boom 104 and is adapted to move the stick 106 with respect to the boom 104 . An E-stick cylinder 116 extends between the stick 106 and the E-stick 108 . The E-stick 108 and the E-stick cylinder 116 are contained within the stick 106 so that the E-stick 108 controllably slides, i.e., extends and retracts, relative to the stick 106 . The work implement 110 is pivotally connected to the E-stick 108 and is moved by a work implement cylinder 118 , extending from the E-stick 108 to the work implement 110 . Hydraulic cylinder valves, shown in FIG. 2 , may control the extension and retraction of the hydraulic cylinders 112 , 114 , 116 , 118 . A boom valve 208 may be associated with the boom cylinder 112 , a stick valve 210 may be associated with the stick cylinder 114 , an E-stick valve 212 may be associated with the E-stick cylinder 116 , and a work implement valve 214 may be associated with the work implement cylinder 118 . The position of valves 208 , 210 , 212 , 214 may be controlled to coordinate the flow of hydraulic fluid to thereby control the rate and direction of movement of the associated hydraulic cylinder 112 , 114 , 116 , 118 . It should be noted that the term “extension amount” represents both the amount of extension or retraction of the hydraulic cylinders 112 , 114 , 116 , 118 . FIG. 2 shows a controller 200 for operating and controlling the movement of the work machine arm 102 . As described in greater detail below, the controller 200 may be adapted to move the components of the work machine arm 102 in an order that is based on a pre-selected priority of movement. For the purposes of this application, the term “pre-selected priority of movement” refers to a hierarchy of movement where the relative position of one or more of the hydraulic cylinders 112 , 114 , 116 , 118 is changed only after another of the hydraulic cylinders 112 , 114 , 116 , 118 is extended or retracted beyond a pre-designated position or amount. Accordingly, the pre-selected priority of movement prioritizes the movement of the boom cylinder 112 , the stick cylinder 114 , the E-stick cylinder 116 , and the work implement cylinder 118 . The cylinder with the higher priority is moved to or beyond a certain point before moving a cylinder with lower priority The controller 200 includes an input device 202 and a control module 204 for operating valves 208 , 210 , 212 , 214 to control the position and movement of hydraulic cylinders 112 , 114 , 116 , 118 on the work machine arm 102 . It may also include displacement sensors 216 , 218 , 220 , 222 associated with, and adapted to monitor the position of the hydraulic cylinders 112 , 114 , 116 , 118 . A mode selector 224 may also be associated with the control module 204 . The input device 202 could be a joystick, keyboard, lever, or other input device known in the art. Adapted to generate a desired movement signal, the input device 202 receives an input from an operator and sends it to the control module 204 . In the exemplary embodiment shown, the controller 200 includes a single input device for controlling the operation of the boom cylinder 112 , the stick cylinder 114 , the E-stick cylinder 116 , and work implement cylinder 118 . However, other input devices may be used to control the operation of one or more of the cylinders independent of the input device 202 and the pre-selected priority of movement. For example, in one exemplary embodiment, the input device 202 controls only the movement of the stick cylinder 114 , the E-stick cylinder 116 , and the work implement cylinder 118 . In this exemplary embodiment, the boom cylinder 112 is controlled by a separate input device for independent control of the boom 104 . Accordingly, in this embodiment, only the stick cylinder 114 , the E-stick cylinder 116 , and the work implement cylinder 118 are subject to the pre-selected priority of movement. The control module 204 may include a processor 205 and a memory device 206 . The memory device 206 may store one or more control routines or prioritized modes, which could be software programs, for controlling the work machine arm 102 based on the pre-selected priority of movement. The processor receives the input signal from the input device 202 and executes the routines or prioritized modes to generate and deliver a command signal to actuate the hydraulic cylinder valves 208 , 210 , 212 , 214 that are associated with the hydraulic cylinders 112 , 114 , 116 , 118 of the work machine arm 102 according to the pre-selected priority of movement. As shown in FIG. 2 , a displacement sensor may be associated with each hydraulic cylinder. For example, a boom displacement sensor 216 may be associated with the boom cylinder 112 , a stick displacement sensor 218 may be associated with the stick cylinder 114 , an E-stick displacement sensor 220 may be associated with the E-stick cylinder 116 , and a work implement displacement sensor 222 may be associated with the work implement cylinder 118 . The displacement sensors 216 , 218 , 220 , 222 may be used to measure the extension amount of the hydraulic cylinders 112 , 114 , 116 , 118 . The displacement sensors 216 , 218 , 220 , 222 may be in communication with the control module 204 , and may provide signals to the control module 204 indicative of the cylinder extension amounts. The control module 204 may monitor one or more of the displacement sensors 216 , 218 , 220 , 222 at a single time, but does not need to monitor them all at the same time. The control module 204 may use the information received from the displacement sensors 216 , 218 , 220 , 222 to prioritize and order movement of the work machine arm 102 based on the pre-selected priority of movement. In the exemplary embodiment shown, the controller 200 includes more than one control routine or prioritized mode. Accordingly, a mode selector 224 is provided in communication with the control module 204 . The mode selector 224 is an input device that allows an operator to select or choose from the available modes, and could be a toggle, joystick, dial, or any other input device known in the art. Accordingly, the operator can select the priority of movement of the work machine arm 102 that will provide the desired results for the work site. The work machine 100 may include any number of modes and each mode may be different and may be based upon a specific use or function of the work machine. For example, one exemplary mode may be a digging mode, where the pre-selected priority of movement requires that the stick cylinder 114 and the boom cylinder 112 be substantially fully extended before allowing movement of either the work implement cylinder 118 or the E-stick cylinder 116 . The priority of movement may allow simultaneous extension of the boom cylinder and the stick cylinder, or may require that they too be moved in order, based on the priority of movement. Other modes having a different pre-selected priority of movement may be used to accomplish other desired purposes. For example, in one exemplary mode, the pre-selected priority of movement prioritizes only the movement of the stick 106 , the E-stick 108 , and the work implement 110 . In this exemplary mode, the pre-selected priority of movement allows movement of the work implement cylinder 118 only after the stick cylinder 114 is extended or retracted beyond a designated point. And the E-stick cylinder 116 may be moved only after the work implement cylinder 118 is extended or retracted beyond a designated point. In this exemplary mode, the extension and control of the boom 104 may be operated independently of and outside of the pre-selected priority of movement. For example, control and operation of the boom 104 may be controlled separately through an input device specific to the boom 104 , such as a boom joystick. In another exemplary mode, only the stick cylinder 114 and the work implement cylinder 118 are controlled by the pre-selected priority of movement. Accordingly, the pre-selected priority of movement allows movement of the work implement cylinder 118 only after the stick cylinder 114 is extended or retracted beyond a designated point. In this exemplary embodiment, the movement of the E-stick cylinder 116 and the movement of the boom cylinder 112 may be independently controlled by, for example, a separate boom joystick and a separate E-stick joystick. In yet another exemplary mode, the pre-selected priority of movement controls only the stick cylinder 114 and the E-stick cylinder 116 . Accordingly, the pre-selected priority of movement may allow movement of the E-stick cylinder 116 only after the stick cylinder 114 is extended or retracted beyond a designated amount. In this exemplary mode, the boom cylinder 112 and the work implement cylinder 118 may be independently controlled and not based on the priority of movement. In any exemplary mode, the pre-selected priority of movement during retraction of the work machine arm 102 may or may not be the reverse of the pre-selected priority during extension of the work machine arm 102 . Other modes would be apparent to one skilled in the art. It should be noted that any mode may be adapted to include an optional transitioning feature for smoothly transitioning the movement from one hydraulic cylinder to the next hydraulic cylinder. This transitioning feature may be used to slow, or ramp down the velocity of one hydraulic cylinder when it is extended or retracted beyond the pre-designated position, while at the same time, ramping up the velocity of the next hydraulic cylinder. So doing provides a smooth transition between hydraulic cylinders as the work machine arm is operated. FIG. 3 is a block diagram 300 showing steps for moving the work machine arm 102 based on the pre-selected priority of movement. The flow chart 300 begins at a start step 302 . At a step 304 , an operator selects a mode on the work machine 100 using the mode selector 224 . The selected mode may be any routine or process that controls the movement of the work machine arm 102 using a pre-selected priority of movement. At a step 306 , the input device 202 generates a signal to change the position of the work machine arm 102 . The signal is sent from the input device 202 to the control module 204 . At a step 308 , the control module 204 determines the extension amount of the hydraulic cylinders 112 , 114 , 116 , 118 on the work machine arm 102 based upon measurements taken and signals received from the respective displacement sensors 216 , 218 , 220 , 222 . At a step 310 , the control module 204 adjusts the extension amount of one or more of the hydraulic cylinders 112 , 114 , 116 , 118 on the work machine arm 102 according to the priority of movement for the mode, and further based upon the signal received from the input device 202 . At a step 312 , the flow chart 300 ends. The flowcharts of FIGS. 4 and 5 illustrate an exemplary method of extending and retracting a work machine arm according to an exemplary pre-selected priority of movement. INDUSTRIAL APPLICABILITY An exemplary mode is described with reference to FIGS. 4 and 5 . FIG. 4 illustrates a flow chart 400 detailing the extension of the work machine arm 102 from a carry position to a fully extended or a maximum reach position according to an exemplary pre-selected priority of movement. FIG. 5 illustrates a flow chart 500 detailing retraction of the work machine arm 102 from the maximum reach position according to the exemplary pre-selected priority of movement. In the exemplary pre-selected priority of movement, the stick cylinder 114 has the first priority, the work implement cylinder 118 has the second priority, and the extendable stick cylinder 116 has the third priority. The boom cylinder 112 , in this exemplary embodiment, is operated independent of the pre-selected priority of movement. In this example, the pre-selected priority of movement for retraction is not the reverse of the pre-selected priority of movement for extension, but instead, the same pre-selected priority of movement is assigned to both extension and retraction of the work machine arm 102 . It should be noted that the same or different pre-selected priority of movements may be assigned to extension and retraction of the work machine arm 102 . The flow chart 400 begins at a start step 402 . At a step 404 , a signal is generated by the input device 202 to extend the work machine arm 102 . The control module 204 receives the signal at a step 406 , and monitors the positions of the hydraulic cylinders 114 , 116 , 118 associated with the work machine arm 102 , at a step 408 . This may be accomplished using the displacement sensors 218 , 220 , 222 that are associated with the hydraulic cylinders 114 , 116 , 118 and that send signals to the control module 204 indicative of the position or extension amount of the hydraulic cylinders 114 , 116 , 118 . In this exemplary embodiment of a priority of movement mode, the stick 106 has priority over the other components of the work machine arm 102 . Accordingly, the hydraulic cylinders associated with the E-stick 108 and the work implement 110 may not be extended or retracted until the stick cylinder 114 is extended beyond a pre-selected extension amount or point. The pre-selected point may be a position where the stick cylinder 114 is substantially fully extended. Thus, the control module 204 will extend the stick cylinder 114 to the pre-selected point before moving the E-stick cylinder 116 and the work implement cylinder 118 . If the stick cylinder 114 is not substantially fully extended, the control module 204 may not move the E-stick cylinder 116 and the work implement cylinder 118 . In one exemplary embodiment, a transitioning feature may slow, or ramp down, the velocity of one hydraulic cylinder, such as the stick cylinder 114 when it is extended or retracted beyond the pre-selected point, while at the same time, ramping up the velocity of the next hydraulic cylinder, such as the E-stick cylinder 116 , to smoothly transition between cylinders. This transitioning feature may be applied to any cylinder, whether extending or retracting. In this exemplary embodiment, and based upon the pre-selected priority of movement, the control module 204 determines whether the stick cylinder 114 is substantially fully extended, at a step 410 . If the stick cylinder 114 is not substantially fully extended, the stick cylinder 114 is further extended at a step 412 . As the stick cylinder is extended at step 412 , the position of the stick cylinder 114 is continually monitored at step 408 . Once the stick is moved to the pre-selected point or substantially fully extended at step 410 , other cylinders 116 , 118 associated with the work machine arm 102 may be allowed to further extend the work machine arm 102 according to the pre-selected priority of movement. In this exemplary embodiment, if the stick is substantially fully extended at step 410 , the work implement 110 may then be moved by the work implement cylinder 118 . If at step 410 the work implement cylinder 118 is substantially fully extended, the pre-selected priority of movement allows movement of the work implement cylinder 118 . At a step 418 , the control module 204 determines whether the extension amount of the work implement 110 is substantially fully extended. It should be understood that due to the configuration of the exemplary work machine arm 102 shown and described with reference to FIG. 1 , that when the work implement cylinder 118 is fully retracted, the work implement 110 is fully extended, or at a maximum reach with respect to the stick 106 and the E-stick 108 . If the work implement cylinder 118 is not fully retracted at a step 420 , the work implement cylinder 118 is further retracted. The position of the work implement cylinder 118 is continuously monitored at step 408 by the work implement displacement sensor 222 and the control module 204 . If the work implement cylinder 118 is fully retracted at step 420 , the E-stick cylinder 116 may be extended at a step 422 . Full extension of the E-stick results in the full extension of the work machine arm 102 , providing a maximum reach. Accordingly, at a step 424 , the extension ends. It should be noted that at any point during extension of the work machine arm 102 , the operator may stop the extension simply by eliminating the signal or generating a contrary signal at the input device 202 . The flow chart 500 of FIG. 5 describes an exemplary method for retracting the work machine arm 102 from the fully extended position. The method described in flow chart 400 and the method to be described in flow chart 500 may be associated with the same mode, such as the digging mode. The flow chart 500 starts at a step 502 . At a step 504 , a signal is generated at the input device 202 to move the hydraulic cylinders 114 , 116 , 118 associated with the work machine arm 102 . At a step 506 , the control module 204 receives the signal from the input device 202 . Because this exemplary mode is a digging mode, at a step 508 , the work implement 110 may be set at a digging angle, such as, for example, 30° with respect to the ground. Further, because the pre-selected priority of movement may be employed with a system for coordinated movement, the work implement 110 may be maintained at the digging angle during the process described for retracting other components of the work machine arm 102 . At a step 510 , the positions of the hydraulic cylinders 114 , 116 , 118 are monitored by the displacement sensors 218 , 220 , 222 . At a step 512 , the control module 204 determines whether the stick cylinder 114 is substantially fully retracted. Because the stick cylinder 114 has the highest priority of movement, the control module 204 may not change the extension amounts of the E-stick cylinder 116 and the work implement cylinder 118 until the stick cylinder 114 is substantially fully retracted. If the stick cylinder 114 is not substantially fully retracted, at a step 514 , the stick cylinder 114 is retracted. Step 510 monitors the position of the stick cylinder to determine when the stick cylinder 114 is substantially fully retracted. According to the pre-selected priority of movement, at step 512 , after the stick cylinder 114 is substantially fully retracted, the work implement cylinder 118 may be moved next. At a step 520 , the control module determines whether the extension amount of the work implement cylinder 118 is fully extended. When the work implement cylinder 118 is fully extended, the work implement 110 is in a fully retracted position or, if the work implement is a bucket, the work implement 110 is in a fully curled position. If the extension amount of the work implement cylinder 118 is not fully extended, the position of the work implement cylinder 118 may be monitored by the work implement displacement sensor 222 and the control module at step 510 . If the work implement cylinder 118 is fully extended, the E-stick cylinder 116 may be retracted. When the E-stick cylinder 116 is fully retracted, the process ends at a step 526 . In the exemplary mode described with reference to FIGS. 4 and 5 , the retraction priority is not the reverse of the extension priority. This is due to the desire during digging to minimize the use and extension of the E-stick cylinder based upon this exemplary pre-selected priority of movement. Further, although the exemplary embodiment of a digging mode described with reference to FIGS. 4 and 5 includes a pre-designated cylinder position that is fully extended or retracted before other cylinders may move according to the priority of movement, such full extension or retraction is not required. In other embodiments, the cylinders need only be extended or retracted beyond any designated point to activate the next priority in the pre-selected priority of movement. Although in the exemplary embodiment describe above, the boom 104 is separately operated, and not controlled by the priority of movement, in another embodiment, the boom 104 is also controlled to the priority of movement of the present invention. Additionally, although the disclosed system is described with reference to a work machine arm 102 for digging, the pre-selected priority of movement may be used on other work machines, including, for example, excavators, shovels, telescopic material handlers, forklifts, etc. For example, if the work implement were pallet forks, the pre-selected priority of movement may operate to prevent tipping the pallet forks. In another example, the pre-selected priority of movement may be used to control a work machine arm during other work scenarios, including, for example, when the work implement 110 is a hydraulic hammer or a vibratory compactor. The pre-selected priority of movement may prioritize the movement of the stick 106 and E-stick 108 , and may be coordinated so that the hydraulic hammer or vibratory compactor is always vertical, with only the stick 108 and E-stick 110 being prioritized. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims.

A method of controlling the movement of a work machine arm having a series of hydraulic cylinders operatively engaged with the work machine arm includes receiving a signal from an input device to change the position of the work machine arm and determining an extension amount of one or more of the series of hydraulic cylinders. The extension amount of one or more of the series of hydraulic cylinders is changed to effect the change in the position of the work machine arm. The changes in the extension amount of the one or more of the series of hydraulic cylinders are ordered based on a pre-selected priority of movement.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of Upchurch U.S. patent application Ser. No. 369,209, filed Apr. 16, 1982, entitled "Pressure Responsive Perforating and Testing System." BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to well perforating systems, and particularly to an apparatus for a new and improved perforating system in which differential pressure is employed to activate a perforating device. 2. Description of the Prior Art Numerous systems have been proposed for perforating a well. Examples of prior art systems employed in combination with a string of tubing or pipe are shown in U.S. Pat. Nos. 2,092,337; 2,169,559; 2,330,509; and 2,760,408. In accordance with these disclosures the firing assembly which activates the perforating gun is actuated by electrical means, pipe string manipulation or by dropping an impact bar (commonly referred to as a "go-devil") through the pipe string. Electrical actuation normally requires that a wireline be run into the pipe string which involves cumbersome and often time-consuming operations. Systems using pipe string manipulation typically include somewhat complicated mechanical constructions, and can be prematurely activated as the pipe string is being run into the well. Systems employing drop bars are not considered to be practical in deviated wells since the bar may not reach bottom. Of course in all cases safety is a primary consideration. SUMMARY OF THE INVENTION It is the general object of the present invention to provide an apparatus for a new and improved well perforating system wherein the perforating device can be actuated with increased safety and reliability under controlled well conditions. It is a further object of the invention to provide an apparatus for a new and improved well perforating system wherein actuation of the firing mechanism is responsive to the existence of a predetermined difference between pressures at different locations in the well bore, such as a pressure difference developed across a packer that has been set to isolate an interval of the well. These and other objects are attained in accordance with the present invention through the provision of a well perforating system comprising means for isolating an interval of a well bore and means for perforating the isolated interval in response to a predetermined difference between the pressure of fluid in the isolated interval and the pressure of fluid in the well annulus outside the isolated interval. In a preferred embodiment of tubing-conveyed perforating apparatus, described in greater detail below, a perforating device suspended in the well as part of a tubing string is arranged to be selectively activated by a firing mechanism that includes a firing pin spaced above a percussion cap that will ignite a detonating cord when impacted by the firing pin. The firing pin is locked in the spaced position by a locking mechanism which is arranged to be released when a predetermined magnitude of pressure differential is applied thereto. Upon release of the locking mechanism the firing pin is driven into engagement with the percussion cap to cause the perforating device to be actuated. In a modified form of preferred embodiment, the firing mechanism and locking mechanism elements are positioned peripherally of the central bore of the tubing string. This leaves an unobstructed central bore for delivering production fluids to the surface following perforation, or as an access channel for running other tools into the well. The firing means of the present invention is pressure actuated, and has simple construction and operability that provides advantages in universal application, including the perforation of highly deviated wells. The system may be actuated in response to a predetermined pressure differential which is developed in a controlled manner, as for example across a well packer or between the annulus and the interior of the tube, thereby providing greater control of the perforating process with attendant increased reliability and safety. There have thus been outlined rather broadly the more important objects, features, and advantages of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described more fully hereinafter. Those skilled in the art will appreciate that the conception on which this disclosure is based may readily be utilized as the basis for the designing of other arrangements for carrying out the purposes of this invention. It is important, therefore, that this disclosure be regarded as including such equivalent arrangements as do not depart from the spirit and scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention have been chosen for purposes of illustration and description of both the apparatus and method, and are shown in the accompanying drawings forming a part of the specification, wherein: FIG. 1 is a schematic view of an embodiment of a tubing-conveyed well perforating system in accordance with the present invention shown by way of example as part of a test string disposed in a well; FIGS. 2A-2D are longitudinal sectional views (right side only) of a portion of the system of FIG. 1, each successive drawing figure forming a lower continuation of the preceding figure; and FIGS. 3A-3D are views corresponding to those of FIGS. A-2D of a modified form of the well perforating system shown in FIGS. 1 and 2A-2D. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring initially to FIG. 1, there is shown schematically a string of formation testing and perforating tools that are suspended in a cased well bore on pipe string 10. The tool string includes a main test valve assembly 11 of the type shown in Nutter U.S. Pat. No. Re 29,638 that includes a valve element which responds to changes in the pressure of fluids in the annulus 12 in order to open and close a flow passage extending upwardly through the valve assembly. The lower end of the main test valve assembly 11 is connected to a recorder sub 13 that houses a pressure recorder which records the pressure of fluids in the passage as a function of elapsed time as the test proceeds. The lower end of the recorder sub 13 is connected to a pressure transfer sub 14 having lateral ports 15 in communication with the well annulus, and the transfer sub is connected to a seal nipple 16 which extends downwardly through the bore of a packer 17 of conventional construction. The packer 17, which can be a permanent-set device, typically includes normally retracted slips and packing elements which can be expanded to provide an anchored packoff in the well casing 18. The mandrel of the packer has a seal bore which receives the seal nipple 16, and an upwardly closing valve element such as a flapper element 20 serves to automatically close the bore to upward flow of fluids when the seal nipple and components therebelow are withdrawn. A slotted or perforated section of tail pipe 21 is connected below the seal nipple 16 and functions to enable formation fluids to enter the flow passage through the tools when the valve element included in the main test valve assembly 11 is open. The lower end of the tail pipe 21 is connected to a hydraulically operable firing sub 22 that is constructed in accordance with the present invention. The firing sub 22 is arranged to cause the selective operation of a perforating gun 23 which is connected to its lower end, the gun including a plurality of explosive charges (e.g. shaped-charges) that upon detonation provide perforations through the wall of the casing 18 and into the formation to enable connate formation fluids to enter the well bore. Another recorder 24 may be connected to the lower end of the perforating gun 23 to provide for additional pressure records. Turning now to FIG. 2A for a detailed illustration of the various structural components of the embodiment, the pressure transfer sub 14 has a threaded box 30 for connection to the recorder housing 13 and a threaded pin 31 for connection to the upper end of the mandrel 32 of the seal nipple 16. A plurality of radially directed ports 15 extend through the wall of the sub 14 to communicate the well annulus above the packer 17 with the interior bore 33 of a small diameter pressure tube 34 which extends downwardly through the seal nipple mandrel 32. The annular space 35 between the inner wall of the seal nipple 16 and the outer wall of the tube 34 provides a portion of the test passage which is communicated by vertical ports 36 with the test passage section above the transfer sub 14. Typical seal elements 37 are carried on the outer periphery of the seal nipple, and engage wall surfaces of the packer mandrel to prevent fluid leakage. The lower end of the seal nipple 16 is connected by a collar 38 to the upper end of the slotted tail pipe 21 which has a plurality of ports 40 through which formation fluids can enter. An adapter sub 41 and a collar connect the lower end of the tail pipe 21 to a section of tubing 42 which can be used to space the firing sub and perforating gun a selected distance below the packer 17. The lower end of the pressure tube 34 is sealed by "O"-rings with respect to the adapter sub 41. As shown in FIG. 2C, the lower end of the tubing section 42 is connected by threads 43 to the upward end of the firing head assembly 22. The assembly 22 includes an upper adapter 45 that is threaded to an upper housing section 46 which, in turn, is threaded to a lower housing section 47. The adapter 45 has a transverse wall section 48 provided with ports 49 to communicate the interior bore 51 of the housing section 46 with the bore 52 of the tubing 42 and thus with the bore 33 of the pressure tube 34 thereabove. Movably received in the bore of the housing section 46 is an actuator sleeve piston 53 carrying seal rings 54 that engage a cylindrical wall surface 55 of the housing section 46. The sleeve piston 53 has a closed upper end, and an external upwardly-facing shoulder 56 that normally engages a downwardly-facing shoulder 57 on the housing section 46. A shear pin 58 that is threaded into the wall of the housing section 46 has an inner end portion 60 that engages in an external annular groove 61 of the piston 53. The lower end portion 62 of the sleeve piston 53 provides an inwardly-facing annular locking surface 63 that normally engages a plurality of circumferentially spaced dogs 64 which extend through windows in the upper end section 65 of an extension sleeve 66 and into engagement with an annular groove 67 formed in the upper end of an elongated firing pin 70. When engaged as shown, the dogs 64 prevent axial movement of the firing pin 70 from the position shown in FIG. 2C. One or more ports 71 extend through the wall of the housing section 46 to communicate the interior region of the sleeve piston 53 via one or more ports 71' and the upper end surface of the firing pin 70 with the pressure of fluids in the isolated interval of the well below the packer 17. The firing pin 70 extends downwardly through a seal 72 (FIG. 2D) on the upper end portion 73 of the lower housing section 47, and is provided with a downwardly facing shoulder 74 against which a retainer 75 is pressed by a coil spring 76. The lower end of the spring 76 bears against an upwardly facing shoulder 77 on a guide ring 78 that is threaded into the housing section 47. The lower end of the firing pin 70 is provided with a protrusion 80 that is adapted upon downward movement of the pin 70 to impact and cause firing of a detonator in the form of a percussion cap 81 mounted in a retainer assembly 82. The upper end of a length of Primacord™ detonating cord 83 is fitted into the lower end of the retainer assembly 82 and is arranged in a well known way to burn when the cap 81 is detonated. The detonating cord 83 extends downwardly within the housing 85 of the perforating gun assembly 23 which is sealed at atmospheric pressure in a conventional manner. The burn of the cord detonates the shaped charges to cause perforation of the casing 18 in a well-known manner. In operation, the parts and components of the embodiment of the perforating system are assembled as shown in FIGS. 1 and 2A-2D. The packer 17 is set in the well casing in a conventional manner to isolate an interval of the well bore. The tool string is lowered into the well, its lower end being inserted through the bore of the packer 17, pushing the flapper valve 20 open. The tool string descends until the seal nipple 16 enters and stops within the packer mandrel bore in order to seal off the interval of the well below the packer from the hydrostatic pressure of the fluid standing in the well annulus above the packer. The pipe string 10 may be filled with a column of water to provide a cushion in order to enable control of the pressure differential when the test valve assembly 11 is opened. To open the test valve assembly 11, pressure is applied at the surface to the well annulus 12 to actuate the valve element therein in the manner disclosed in Nutter U.S. Pat. No. Re 29,638. This pressure acts via the transfer sub ports 15, the pressure tube 34 and the bore of the tubing 42 on the upper end surface of the sleeve piston 53. The strength of the shear pin 58 is selected so that it will not fail and thereby enable release of the firing pin 70 until a greater differential is applied thereto than is employed to activate the main test valve assembly 11. With the main valve 11 open, suitable valves can be manipulated at the surface to slowly bleed down the pressure in the pipe string 10 to thereby increase the pressure differential acting on the sleeve piston 53 until the pin 58 shears. When the pin 58 shears, the sleeve piston 53 moves suddenly downward to position the locking surface 63 below the latch dogs 64, which then shift outwardly to release the firing pin 70. The firing pin 70 is then forced downwardly by the pressure in the well bore below the packer, and impacts the percussion cap 81 to cause the same to ignite the detonating cord 83, thereby firing the perforating gun 23. Since the pressure in the isolated interval of the well has been substantially reduced, the perforations are made under conditions of "underbalance," i.e., the pressure in the well bore is less than the formation fluid pressure, so that there is an immediate cleansing effect as formation fluids enter the well casing. Since all fluid flow is toward the well bore, the formation is not damaged as may happen where perforating is done under overbalanced conditions. Once communication has been established through the casing between the formation and the isolated well interval, a test of the well can be carried out in the customary manner by closing and opening the valve in the test assembly 11 to alternately shut-in and flow the formation. The flow and shut-in pressures are recorded by the gauges at 13 and 24. After completion of testing, the tool string may be withdrawn from the packer element 17 and removed from the well. The packer 17 remains in position for subsequent production operations. Although the use of a permanent-type production packer 17 has been illustrated and described herein, it will be appreciated that a typical retrievable type packer could be used which is an integral part of the tool string located between the transfer, sub 14 and the slotted tail pipe 21. In this case of course the packer element would be run into the well casing with the tool string and operated to temporarily pack off the well interval to be perforated and tested. FIGS. 3A-3D illustrate a modified form of embodiment of well perforating system disposed as part of a tubing string. The embodiment of FIGS. 3A-3D is a "full-bore" embodiment that may be run together with testing tools, or without any testing tools as part of a permanent well completion system. As shown in the drawings, the perforating tools are incorporated into the string in such a way that the central bore is unobstructed. This offers the advantage that tools can be run on wireline or narrower diameter piping down through the tubing string, unhindered by the perforating system components. Furthermore, the unobstructed central bore is available to serve as a conduit for passing the fluids produced by the well after perforation. The firing mechanism in the arrangement of FIGS. 3A-3D has a general annular construction, the firing pin and actuating assemblies being arranged within the tubing string, peripherally of its central bore. As shown in FIGS. 3A-3D, a top sub 100 having a full bore therethrough includes a threaded box at its upper end for connection in the tubing string. A plurality of tubular members successively connected below the top sub 100 serve to house the perforating system elements as part of the tubing string, providing a constant outside diameter and an unobstructed central bore throughout. These other tubular members include a shear pin housing 102 threadably engaged to an intermediate portion of the top sub 100, (FIGS. 3A-3B); a spring housing 104 threadably connected below the housing 102 (FIGS. 3B-3C); a firing pin housing 106 threadably connected below the housing 104 (FIGS. 3C-3D); and a detonator housing 108 threadably connected to the housing 106 (FIG. 3D). The detonator housing 108 provides a point of connection for the rest of the tubing string 110 which includes a perforating gun. Such other tools and tubing string elements, (e.g. slotted section of tail pipe, test tools and so forth) may be connected in the lower part of the tubing string 110, as desired for the particular application. The "full-bore" perforating system arrangement of FIGS. 3A-3D provides great latitude as to its point of connection in the tubing string. The firing mechanism may even be connected to be entirely above the location of a packer used to isolate the well interval being perforated. In such case, a lengthened detonating cord may be extended down the periphery of the tubing through the packer and into connection with the perforating gun located below the packer. A firing mechanism actuator in the form of a tubular piston is slidably mounted within the housing members 100, 102, 104, 106 and 108 as shown in FIGS. 3B-3D. The actuator comprises upper and lower sections consisting of a latch mandrel 112 threadably engaged above a firing pin actuator sleeve assembly 114. The actuator piston is mounted to move longitudinally of the tubing string from a position in which the top of the latch mandrel 112 abuts the bottom of a narrowed outside diameter portion of the top sub 100 (FIG. 3B) to a position in which the bottom of the sleeve assembly 114 is brought into contact with an inside shoulder formed by a widened inside bore portion at the top of the detonator housing 108. The actuator piston assembly is mounted so that when it is driven to its downward position, it drives a firing pin 116 downwardly against a percussion detonator 118 (FIGS. 3C-3D), thereby causing the firing of a plurality of explosive charges mounted within a perforating gun carried in the lower part of the tubing string 110. The firing pin 116 is in the form of a pointed rod that depends from an annular spring retaining element 120 (see FIG. 3C). The bottom of the firing pin 116 is received within a tubular bore of the detonator housing 108 that extends parallel to the axis of the tubing string. The detonator 118 is also rod-like and projects upwardly into a larger diameter portion of the same bore at the lower part of the housing 108. A Primacord™ detonating cord or other suitable means for delivering the detonation effect from the detonator 118 to the explosive charges located in the perforating gun is connected below the detonator 118. A helical spring 122 is positioned within a cavity formed by a reduced outside diameter lower part of the sleeve assembly 114, a greater inside diameter lower portion of the firing pin housing 106 and the top of the detonator housing 108. The spring 122 connects between the top of the housing 108 and the spring retaining element 120 and serves to bias the firing pin 116 in a position spaced from the detonator 118, with the top of the element 120 abutting the internal shoulder at the top of the larger inside diameter portion of the housing 106. For ease of operation it has been found advantageous to provide a plurality of firing pins 116 depending at evenly spaced locations from the annular element 120 into a corresponding plurality of peripheral bores in the housing 108. It is sufficient that only one of the bores be provided with a detonator 118. However, the firing pins not mating with a detonator act as guides to ensure the smooth movement of the firing pin that does mate with a detonator. A second helical spring 124 is positioned within an annular cavity formed by the lower larger inside diameter portion of the spring housing 104, the upper outer portion of the sleeve assembly 114, the bottom of the latch mandrel 112, and the top of the firing pin housing 106 (FIG. 3C). The spring 124 is received between an annular spring guide 126 at the top of the cavity and a spring washer 128 positioned at the bottom of the cavity. The top of the spring guide 126 abuts an internal shoulder of the housing 104 and the bottom of the mandrel 112, as shown in FIG. 3C. A sealed atmospheric chamber 129 is provided between the inner surface of the housing 106 and the outer surface of the actuator sleeve 114. The spring 124 serves to bias the actuator piston 112, 114 in its upmost position with the top of the mandrel 112 positioned adjacent the bottom of the top sub 100. The atmospheric chamber 129 acts to bias the piston 112, 114 downwardly when pressure is greater in the central bore. The actuator piston 112, 114 is locked in its upmost position by means of a latch or locking mechanism 130. The locking mechanism 130 includes a latch 132 (FIG. 3B) which locks a split latch ring 134 into engagement with an external annular groove or recess of the latch mandrel 112. A latch stop ring 136 positioned above the top of the spring housing 104 supports the split ring 134 against downward movement. When the ring 134 is within the external groove of the mandrel 112, the piston actuator 112, 114 is locked against downward movement, and activation of the firing element 116 is prevented. The top of the latch 132 includes an internal downwardly-facing shoulder which engages with an external upwardly-facing shoulder of an extension element 138 threadably engaged to the bottom of a latch piston 140. The two shoulders are urged into engagement by a latch spring 142, as shown in FIG. 3B. A shear pin 144 extending through a bore in the upper section of the shear pin housing 102 between the housing 102 and the latch piston 140 immobilizes the latch piston 140 against downward movement (FIG. 3A). The components of the latch mechanism 130 are received within the annular cavity defined by an upper section 146 and a lower section 148. One or more ports 150 (FIG. 3A) serve to maintain the pressure in the upper section 146 at equilibrium with the pressure in the annulus of the borehole. Seals 152 and 153 (FIG. 3B) serve to isolate the lower section of the cavity 148 from the pressure in the upper section of the cavity 146. One or more ports 154 (FIG. 3B) in the latch mandrel 112 serve to equalize the pressure in the lower cavity section 148 with that of the internal central bore of the tubing string. It can be seen therefore from the arrangement of FIGS. 3A and 3B that the pressure difference between the pressure in the annulus delivered at the port 150 and the pressure in the central bore of the tubing string delivered at the location of the port 154 is caused to act on the latch piston 140. Should the annular pressure acting on the upper cavity section 146 exceed the tubing bore pressure acting on the lower cavity section 148 by an amount greater than the shear strength of the pin 144, the latch piston 140 will be driven downwardly against the latch 132. Use of the mating shoulder and spring arrangement of the latch mechanism 130 (shown by elements 132, 138, 140 and 142 in FIG. 3B) serves to isolate the force necessary to shear the pin 144 from the effect of the inertial and frictional forces associated with the consequential downward movement of the latch 132. An interval of "dead" travel is provided between the shearing of the pin 144 and the point at which the downward travel of the bottom of the latch piston 140 pushes the latch 132 down. This ensures a "clean" shear of the pin 144. In operation in a typical commercial application, the pressure applied to the upper cavity section 146 will be the pressure of fluid in the annulus of the borehole above a packer that has been set to isolate the well interval to be perforated. The pressure applied to the lower cavity section 148 will typically correspond to the pressure of fluid in the isolated interval below the packer. The shear strength of the pin 144 and the spring constants of the springs 122, 124 and 142 are selected so that when the desired pressure difference between the annulus and the tubing bore exists, the pin 144 will break, the latch mechanism 130 will be released and the actuating piston 112, 114 will drive the firing pin 116 downward against the detonator 118. When the pin 144 breaks, the latch piston 140 is forced downwardly by the pressure differential applied across it. After a brief interval of "dead" travel, the latch piston 140 comes into contact with the latch 132, pushing it downward to a point where a larger inside diameter portion of the latch 132 moves into position adjacent to the split latch ring 134. The latch ring 134 will travel out of the external groove of the mandrel 112, thereby freeing the actuator piston 112, 114 for downward movement against the bias of both the spring 124 and the chamber 129, and driving the firing pin 116 against the bias of the spring 122 into percussive engagement with the detonator 118, thereby firing the gun. Having thus described the invention with particular reference to the preferred forms thereof in the context of perforating systems incorporated into a tubing string, it will be obvious to those skilled in the art to which the invention pertains, after understanding the invention, that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the claims appended thereto.

A well perforating technique utilizes a predetermined pressure difference developed at different points in the borehole to actuate the firing mechanism of a tubing conveyed perforating gun. A first embodiment incorporated as part of a well test string includes a packer for isolating a wellbore interval and a perforating gun connected in the string below the packer which is fired in response to development of a greater pressure in the annulus above the packer than in the isolated interval, thereby causing perforation at "underbalanced" conditions. A modified "full-bore" embodiment has an annular configuration firing mechanism as part of a tubing string and fires the perforating gun in response to development of a predetermined difference between the pressures at a point in the annulus and a point in the central bore of the tubing string.

You are an expert at summarizing long articles. Proceed to summarize the following text: [0001] This application claims priority of PCT application PCT/EP2005/012538 having a priority date of Nov. 23, 2005, the disclosure of which is incorporated herein by reference. TECHNICAL FIELD [0002] The invention concerns a rail for a self-propelled electric trolley. BACKGROUND OF THE INVENTION [0003] Rails of the type mentioned above are known from many examples. [0004] CH 515 819 describes such a rail in which the C-shaped sides of the rails engage the side wheels of the trolley. The wheels in turn run on the upper or lower edges of the C-shaped sides. For lateral support, radially projecting support rims, which function in concert with the side parts of the sides of the rail, are provided along the circumferential running surfaces of the trolley wheels on the side facing away from the sides. Because they can be easily damaged, the support rims make the trolley wheels relatively complicated and vulnerable. The support rims may also cause damage to a surface on which the trolley is placed outside the rail. Finally, the rail is also relatively complicated, because it requires a ledge on which the support rims can be supported laterally to be present between the sides and the base part of the rail. In overhead suspension operation, the support rim exerts force on the outer edge of the sides, making it necessary for these parts to be of thick construction to prevent bending. They therefore require a relatively high amount of material and are thus costly. [0005] WO95/14599 presents an improved rail in which the C-shaped sides connect evenly to the base part and no ledges are necessary. For the trolley wheels, the support rims are replaced by lateral guide wheels within the wheels, which abut the center of the sides. Because the guide wheels engage the center of the sides, less supporting force needs to be exerted by the sides and the rails can therefore be of lighter construction as a result of the supporting forces acting at a lower level. However, this rail may only be used by trolleys with lateral guide rollers. SUMMARY OF THE INVENTION [0006] The object of the invention is to create a novel type of rail, which allows mixed operation of trolleys with and without lateral guiding rollers. [0007] If each C-shaped side features a central, outwardly displaced running area for the lateral guide rollers of the trolley and upper and lower support surfaces for the side wheel inclined towards the wheel, where the running areas and the support surfaces areas are used in alternation, then the rail can be used by both trolleys with simple wheels without support rims and by trolleys with lateral guide rollers. The simple wheels rest on the lower support surfaces when the trolley is driven on a normal level, or on the upper support surfaces when the trolley is driven suspended overhead. On trolleys with lateral guide rollers, these rollers abut the middle running area of the C-shaped sides of the rails. The novel rail thus facilitates mixed operation by both types of vehicles. [0008] The special profiling of the C-shaped sides of the rails reduces the bending of the sides when overhead suspension is employed. Less material is required to construct the rail, while at the same time the trolley can be loaded more heavily. The space gained through the upper guide bevel of the side can be used for integrating the assembly grooves. [0009] Advantageous configurations of the rails are detailed in the following exemplary embodiments. BRIEF DESCRIPTION OF THE DRAWINGS [0010] The exemplary embodiments of the invention are described in greater detail with reference to the drawings, wherein: [0011] FIG. 1 A rail with a trolley without lateral guide rollers, frontal view; [0012] FIG. 2 A rail with a trolley with lateral guide rollers, frontal view [0013] FIG. 3 The rail shown in FIGS. 1 and 2 without trolley; [0014] FIG. 4 Diagrammatic illustration of the rail shown in FIG. 3 ; [0015] FIG. 5 Side view of the connection between two rail segments; [0016] FIG. 6 Side view of the connection between two rail segments with expansion joint; [0017] FIG. 7 The rail shown in FIG. 3 only with power rails; [0018] FIG. 8 The rail shown in FIG. 7 in section VIII-VIII from FIG. 7 ; [0019] FIG. 9 The rail shown in FIG. 7 in section IX-IX from FIG. 7 ; [0020] FIG. 10 Diagrammatic illustration of a concave rail segment; [0021] FIG. 11 Diagrammatic illustration of a convex rail segment; [0022] FIG. 12 Diagrammatic illustration of a laterally curved rail segment; [0023] FIG. 13 A base segment part for connecting the sides of the rail shown in FIG. 12 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0024] FIGS. 1 and 2 show a cross section of a segment of a conveyor system that features rails 2 in which a self-propelled trolley 4 is arranged. One such rail 2 features a base part 6 and C-shaped sides 8 , 10 , which enclose the side wheels 12 of the trolley 4 . The C-shaped sides 8 , 10 each feature a central, outwardly displaced running area 14 for the lateral guide rollers 16 of the trolley, as well as upper and lower support surfaces 18 , 20 , each inclined towards the wheel 12 . One and the same rail is thus suited for trolleys 4 that feature lateral guide rollers 16 , as shown in FIG. 2 , and for trolleys 4 without lateral guide rollers, but on which the wheels 12 simply abut the support surfaces 18 , 20 . [0025] The wheels 12 and the guide rollers 16 are generally non-powered wheels or rollers without any drive function. Drive is provided on the one hand by a frictional wheel 22 functioning in concert with a corresponding frictional surface 24 of the rail 2 , and/or a cog 26 functioning together with a cog rail 28 of the rail 2 . Sliding contacts 30 , 32 , 34 function together with power rails 36 , 38 , 40 in the rail and serve to transmit current on the one hand and provide switching and control functions on the other hand. [0026] The details of the rail and its function are illustrated in greater detail in FIGS. 3 through 13 and are further described below. [0027] In the respective upper portion of the C-shaped sides 8 , 10 , the rail 2 features dovetailed assembly grooves 42 , 44 , which accommodate the clampable connection strips 46 for connecting adjoining rail segments 2 a , 2 b to one another. Additional assembly grooves 48 , 50 for accommodating connection strips 46 are arranged on the bottom side of the base part 6 of the rail 2 . To provide a secure connection between adjoining rail sections 2 a , 2 b , the connection strips 46 feature clamping screws 52 for each rail section 2 a , 2 b as FIG. 5 illustrates. To create an expansion joint 54 between segments 2 a , 2 b , the connection strips 46 are fastened to only one rail segment 2 b by means of clamping screws 52 , while the connection strip 46 is displaceably arranged in the other rail segment 2 a as FIG. 6 shows. [0028] The power rails 36 , 38 , 40 are fastened with the aid of sliders 56 , which feature a block part 58 with molded feet 60 , 62 , which engage the dovetailed assembly grooves 64 of the rails 2 . Driven dowel pins 66 between the feet 60 , 62 prevent the sliders 56 from separating from the base part 6 . In FIGS. 7 and 9 , the dowel pins 66 are shown prior to being driven into the opening 68 between the feet 60 , 62 . Recesses 70 for accommodating the power rails 36 , 38 , 40 are arranged in the block part 58 . Lateral to the block part 58 are snap-in pins 72 , which feature snap-in hooks 74 , 76 oriented away from one another, which function together with facing snap-in strips 78 , 80 of the hollow power rails 36 , 38 , 40 . To facilitate connection to a power supply, the heads 82 of contact screws 84 extending through the block part 58 of the slider 56 and the base part 6 of the rail 2 to the opposite side thereof are arranged in the power rails 36 , 38 , 40 . As FIGS. 1 through 3 reflect, the contact screws 84 are secured by means of a first nut 86 , while a second nut 88 serves for clamping the power supply connection 90 . [0029] Arranged on the bottom side of the base part 6 is an additional dovetailed assembly groove 92 for the purpose of fastening cable clips 94 . The latter features clipping feet 96 , 98 , which engage the assembly groove 92 and between which a dowel pin 100 is arranged to prevent the feet from separating from the assembly groove 92 . The cable clips 94 arranged at specific intervals on the bottom side of the base part 6 serve to hold all types of lines such as power supply lines and control lines. The bottom side of the base part 6 can also ultimately be covered with a cover 102 that features side fastening strips 104 , 106 that engage corresponding insert grooves 108 , 110 on the bottom side of the base part. [0030] An additional dovetailed assembly groove 112 for securing the cog rail 28 is arranged on the top side of the base part 6 . [0031] A rail of this kind can be bent to form an inside curve as shown in FIG. 10 or an outside curve as shown in FIG. 11 . For this purpose, the rail can be bent as a whole unit in the manner shown. [0032] To form an inside or outside curve as shown in FIG. 12 , the C-shaped sides 8 a and 10 a must be individually bent according to the desired curvature radius and then connected to one another using the base segment parts 6 a. [0033] The new rail is suited not only for mixed operation by trolleys with and without lateral guide rollers, but, thanks to the assembly grooves and the insert-and-clip connections, can be employed universally, is easy to retrofit, and can be assembled quickly and easily. Rails can be removed and later reused in a simple manner. No complicated tools are required. [0000] Reference number list  2 Rail  2a, 2b Rail segment  4 Trolley  6 Base part  6a Base segment part  8, 8a C-shaped side  10, 10a C-shaped side  12 Wheel  14 Running area  16 Guide roller  18, 20 Support surface  22 Frictional wheel  24 Frictional surface  26 Cog  28 Cog rail  30, 32, 34 Sliding contact  36, 38, 40 Power rail  42 Assembly groove on 8  44 Assembly groove on 10  46 Connection strip  48 Assembly groove on 6  50 Assembly groove on 6  52 Clamping screw  54 Expansion joint  56 Slider  58 Block part  60, 62 Foot  64 Assembly groove  66 Dowel pin  68 Opening  70 Recess  72 Snap-in pin  74, 76 Snap-in hook  78, 80 Snap-in strip  82 Head  84 Contact screw  86 First nut  88 Second nut  90 Power supply connection  92 Assembly groove  94 Cable clip  96, 98 Foot 100 Dowel pin 102 Cover 104, 106 Fastening strip 108, 110 Insert groove 112 Assembly groove for 28

Rail for self-propelled electric trucks, with the rail ( 2 ) having a base part ( 6 ) and C-shaped side flanks ( 8, 10 ) which engage over side wheels ( 12 ) of the truck ( 4 ). In order to improve the rail, each C-shaped side flank ( 8, 10 ) has a central running area ( 14 ), which is offset outwards, for side guide rollers ( 16 ) of the truck ( 4 ) and upper and lower supporting services ( 18, 20 ) which run at an angle to the wheel ( 12 ) for the side wheels ( 12 ), with the running area ( 14 ) and the supporting areas ( 18, 20 ) being used alternately.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED APPLICATION This regular utility patent application is derived from Provisional Patent Application Ser. No. 60/102,897 filed on Oct. 2, 1998. BACKGROUND OF THE INVENTION 1. Field of the Invention The field of the invention is the art of walk-through ladders, inclusive of fixed ladders, which are permanently attached to a structure such as a building. 2. Description of the Related Art A so called "through" ladder requires a climber getting off at the top to step through the ladder in order to reach a landing. "Walk-through" fixed ladders are also well known; they typically include a flared section at the top through which the climber walks. See the prior art device in FIGS. 8 and 9 which will be more fully described below. Fall protection is mandatory through OSHA regulations on fixed ladders over 20 feet tall in general industry and 24 feet tall in construction. The addition of a post or a rail in the center or at the side of the ladder creates an impediment to circumvent so an outside fitting is safer. Ladders could be upgraded by having climbing safety devices installed as extra protection. About half of the ladders in use are less than 20 feet high so such improvements would serve the purpose well if no fall protection exists for these ladders. One problem with the flared walk-through ladder is that the climber routinely holds a side rail while descending until the moment the flared section is reduced to 16 inches in width. Unless users observe the need to place the hands closer to the body in order to grasp the side rails or rungs on the main body of the ladder, a person will grasp at thin air and will be subject to a fall at that moment if he has transitioned his feet and assumed the location of the handhold by getting ready to release the other hand. Moreover, when 21/2-3-inch width angle iron is used as the side rail, only a push-pull pinch grip can be made on the side rails and any fall at the walk-through portion of the ladder is likely to be catastrophic in its outcome. In fact, the ability to hold any vertical shape of the side rails sufficiently to regain balance is not possible. The problems with side rail holdings are several. First, the hand slides down due to the weight of the body. Second, the force of arresting a free fall up to three feet, i.e. the length of the arm, is dynamic. From rope tests, it is known that the maximum force of a moving rope which can be held is 50 pounds and the least is approximately 10 pounds, both far below a person's body weight. These references are found in the ISFP Newsletter of October, 1996. Third, a swing fall into the side of the ladder produces an impact of the body with the ladder since the body's center of gravity has to move eight inches from center to side because a ladder rung is 16 inches long. If a person is standing far over to the side, then a movement of 16 inches will occur with an even higher swing fall collision which further tends to destabilize the hand grip. Fourth, some ladder side rails are impossible to encircle with the hand, e.g., three-inch angle irons or two-inch flange I-beams. Because these shapes cannot be encircled with the hand for a good grip, only a pinch grip can be used and no fall arrest is remotely possible. With two-inch or 21/2-inch widths, grips are possible but, due to the factors described above, the grip cannot become an effective grasp under foreseeable methods of climbing on these ladders and a catastrophe must necessarily follow, if the climber falls. Fifth, the ground or surface below a fixed ladder is almost always unyielding, thus providing the maximum possible deceleration upon impact and therefore the greatest injury to a falling worker. Sixth, ladders constitute the primary cause of injurious occupational falls based on current OSHA statistics. Since these statistics include portable ladders as well as fixed ladders, it is evident that a climber, who loses his balance on a ladder, needs all the help possible to maintain a grasp that can be reasonably effective if a foot were to slip at the most vulnerable transition points on the ladder. All climbers eventually misstep no matter how well they are trained. Usually, the climber is preoccupied about achieving the purpose for which the ladder is climbed, not the actual climbing of the ladder. Therefore, exposure to fall hazards cannot be expected to be controlled effectively solely by training workers to climb ladders with the utmost attention to human factors and back-up safety features. Typical of walk-through ladders in the prior art is the fixed ladder illustrated in FIGS. 8 and 9. A lower section of a walk-through ladder L is shown below a surface A which schematically represents a level to which a climber C is ascending from a lower surface G. The ladder L includes side rails 1 with a plurality of round foot rungs 2. By way of example, each rung 2 can be 16 inches long at a minimum and 3/4 to one inch in diameter. Each side rail 1 can be 21/2 inches wide by 33/8 inch to one-half inch in thickness or any size or shape which provides a power grip with materials, such as carbon steel or aluminum, being selected appropriately for the ladder length, usage and environment. As best shown in FIG. 8, the ladder L at its top above the surface A flares outwardly to form a walk-through section W. The architecture of the walk-through section W may vary depending upon requirements. However, the walk-through section W has parallel vertical side rails 21 and 22 forming an opening O generally, in order to meet code requirements, spaced apart at a distance one from the other about 24 to 30 inches. As it is also seen in FIG. 9, the walk-through opening O is minimally 31/2 feet in height. In this case, if the climber C is about 5'8" tall, the opening O may be about four feet high. In FIG. 9, the climber C ascends the ladder L normally. As the climber C negotiates his way into and through the opening O, as indicated by arrows R, onto the surface A, the climber's feet may slip. The vertical side rails 21 and 22 of FIG. 8, regardless of shape or configuration, cannot be grasped without great risk of the climber's grip sliding and/or opening up, depending upon the nature of the slip. Furthermore, a free fall can develop from zero to twice the climber's arm length, resulting in an impact on any grip that the climber C may have. In addition, a swing to one side of the ladder L may result in an impact against the side rails 1 of the ladder L. Consequently, the climber's grip cannot be maintained and a hard fall to the surface C below usually occurs, resulting in serious injury or death. SUMMARY OF THE INVENTION This invention relates to a modification of walk-through ladders, namely, providing a second plurality of horizontal grasping rungs associated with the walk-through section which ordinarily does not have any such rungs. These extra rungs are provided for the climber to maintain a continuum of hand grips on the ladder. Such additional rungs are situated above the highest ladder rung. These higher horizontal grasping rungs are easier for the climber to grab and hold than the vertical side rails during passage up into and down from the walk-through section of the ladder, if a foot of the climber slips during such mounting and dismounting of the ladder. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view of a first embodiment of the invention. FIG. 2 is a front elevational view of a second embodiment. FIG. 3 is a front elevational view of a third embodiment. FIG. 4 is a front elevational view of a fourth embodiment. FIG. 5 is a front elevational view of a fifth embodiment. FIG. 6 is a schematic perspective view of a sixth embodiment. FIG. 7 is a front elevational view of a seventh embodiment. FIG. 8 is a front elevational view of a prior art ladder. FIG. 9 is a side elevational view of the prior art ladder. FIG. 10 is an alternative embodiment wherein a non-flared walk through section receives elongated sleeves at an upper end thereof so that rungs of the sleeves extend outwardly. FIG. 11 is an alternative embodiment wherein side rails of a flared walk through section receive elongated sleeves such that the rungs of the sleeves are situated within a flared opening. FIG. 12 is an alternative embodiment wherein horizontal grasping rungs replace traditional rungs. FIG. 13 shows the horizontal grasping rung of FIG. 12. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a second plurality of parallel, horizontal grasping rungs 15 are provided in association with the opening O in the walk-through section W of the fixed ladder L, thus allowing a climber C to grab one of the rungs 15 in the same fashion as the grasp enabled by the first plurality of rungs 2 in the lower climbing section of the ladder L. As seen in the simplest embodiment illustrated in FIG. 7, the horizontal grasping rungs 15 extend freely at one end into the plane formed by the side rails 21 and 22 defining the opening O in the walk-through section W of the ladder above the surface A. Any secure fixation or placement of the horizontal grasping rungs 15, whether by affixing them to the side rails 21 and 22 directly or otherwise by placing them securely at the required sites, is satisfactory. Moreover, although not necessarily in every structure providing the same level of protection, where the size of the opening O permits, the horizontal grasping rungs 15 may be placed proximate the opening O. As seen in the third embodiment in FIG. 3, the rungs 15 may be placed outside of the side rails 21 and 22 of the walk through section W. Thus, the horizontal grasping rungs 15 may be in the same plane as the opening O but affixed to the side rails 21 and 22 and extending outwardly therefrom rather than into the opening O of the walk-through section W. This walk-through ladder improvement of the present invention is applicable to other fixed ladders used in industry and construction. For example, as seen in FIG. 1, it is applicable to a job-made ladder L by bolting the rungs 15 at one end to vertically oriented uprights 23 and 24 which extend above the surface A and are aligned parallel to the side rails 21 and 22. Furthermore, the rungs 15 can be either built into new ladders at the time of fabrication or retrofitted to existing ladders. The purpose of the improvement of the present invention is to provide rung-like grab-bars with spacing similar to the ladder rungs 2 which are further down in the lower section of the ladder L. Thus, the climber C who has the task of climbing up or down the ladder L can do so with greater security by holding onto the horizontal grasping rungs 15 rather than onto the vertical uprights 23 and 24 or the side rails 21 and 22 which cannot be grasped effectively for even short time periods if the climber's feet slip during mounting or dismounting from the walk-through section W. Dismounting is typically to a landing onto a roof, mezzanine, platform, parapet or other surface A that may be flat or sloped. The results of a lost grip on the side rails 21 and 22 at the top of the ladder L can be catastrophic with long falls to the ground G or to a lower platform, thus resulting in serious injury or death in many cases each year. This kind of accident can occur even if there is a protective ladder cage (not shown) or if the climber's protection cable (not shown) has been disconnected. It is preferable that the horizontal grasping rungs 15 associated with the walk-through section W be long enough for the climber's hand, either bare or gloved, to hold preferably 4 to 5 inches and up to 6 inches of the rung 15. Also, a diameter of about 1.5 inches is preferred for the rungs 15. Alternatively, rungs 15 of 0.75 inch diameter or other sizes may be welded or bolted for uniformity with the other rungs 2 to meet codes that require this uniformity over ergonomics. Ordinarily after a slip, the hand of the climber C cannot hold the vertical side rail 21 or 22 long enough to regain his balance. Thus, a power grip is now required in the 1992 ANSI A14.3 Code Section. Such a power grip cannot be achieved with the prior art ladder which use side rail 2 of flat material with dimensions of either 3/8"×2" or 3/8"×21/2". The preferred material may be galvanized steel, stainless steel, aluminum, fiberglass or any other sturdy substance capable of holding the human body when the material is bolted on the ladder L. Improved fastening devices can be used to permit a mechanical attachment without the need to drill holes through the ladder L to attach metal bolts thereto. Instead, a single coupling 25, shown schematically in the first embodiment in FIG. 1, could be used for easy fitting of the rungs 15 on each side of the opening O to the side rails 21 and 22 of the walk-through section W. The assembly including the walk-through section W with the horizontal grasping rungs 15 can be bolted together or welded with seamless joints in such a way that the welds will not break under a normal load or through corrosion or by any other reasonably destructive means. The embodiment illustrated in FIG. 2 recognizes that the codes generally call for the flared walk-through section W at the top of the fixed ladder L to broaden outwardly from the rungs 2, which have a 16-inch minimum clear width, to the opening O, which has a clear width of 24 to 30 inches. The additional rungs 15 for climbing protection on the ladder L are accommodated in the opening O which is essentially a higher clear space up to 36 inches in width. However, as one skilled in the ladder art will readily appreciate, the opening O may be decreased in width for safety if it is so desired. Because of the capability of the climber C to span 36 inches which is the maximum allowed by the 1992 A14.3 Code Section without loss of gripping power, the present invention is valuable for increasing safety. If an authority determines that the flaring of the walk through section W is unnecessary for safety and permits the present invention to be placed inside the flared walk-through section W, thereby narrowing the opening O and decreasing the fall space in the opening O, the improvement can be of great help to the climber C without sacrificing his ability to dismount properly, even if necessary to do edgewise, because of the increased hand grasping power allowed by the invention. Thus, the climber C can remount the ladder L for descent more easily and safely since the spacing and location of the rungs 2 and 15 are uniform for the entire length of the ladder L and the walk-through section W in FIG. 2. The width of a climber's hips ranges from 11.1 to 16.4 inches across the front and a climber's buttocks range from 7.6 to 14.0 inches from front to back according to U.S. Army Mil-Std. 1472C (1980). Tools on the climber's body can add to these dimensions, so fitting in sideways helps minimize the climber's contact with the vertical uprights 23 and 24 in FIG. 1. If there are railings 26 as seen in FIG. 4, along the side rails 21 and 22, a fitting 27 may be added to allow the plurality of rungs 15 to be mounted to the side rails 21 and 22 inside the walk-through section W. This fourth embodiment helps the climber C to pull himself manually onto the surface A. Conversely for descent, the closer accessibility of the grasping rungs 15 will be helpful for maintaining confidence of gripping power as the climber C turns around to face the ladder L for descent. As shown in FIGS. 5 and 12, a job-made ladder L can be very dangerous because the side rails 21 and 22 are typically lumber which is virtually impossible for the normal climber C to grasp in order to regain his balance when a slip or a fall occurs. The variation of the present invention illustrated in FIG. 5 shows how the improvement can work with 2×6-inch or 4×4-inch side rails 21 and 22 to increase safety through better handholds. Specifically, the fittings 27 may not be merely attached to one side of the rails 21 and 22, as seen in FIG. 4. Rather, as shown in the fifth embodiment of FIG. 5, fasteners 28 may pass through the side rails 21 and 22 to help secure the fittings 27 thereto. Where no railings 26 are available as seen in the sixth embodiment of FIG. 6, attachments 29 provide railings back from an edge E of the surface A to which the ladder L is fixed. These attachments 29 extend back preferably six feet or more and provide protection on most commercial roof surfaces A. For a parapet ladder L, the horizontal grasping rungs 15 may be secured on both side rails 21 and 22 to the attachment 29 by double couplings 31 and 32. Such double couplings 31 and 32 may be bolt and nut connections. They are illustrated but were not previously discussed in the embodiments shown in FIGS. 2 through 5. Other uses for the horizontal grasping rungs 15 as grab bars are also contemplated for any location where a comfortable handhold is needed to support balance, e.g., on machinery, cranes, platforms, and the like. Such arrangements are within the scope of the present invention. An embodiment of the present invention, where either a flared or non-flared fixed ladder (ladder not shown) is modified by placing elongated sleeves 121 and 122 over side rails 21 and 22, respectively, is shown schematically in FIG. 10. The sleeves are adapted to interfit over and be secured to the side rails. In FIG. 10, rung 15 placement on the sleeves is such that, after the sleeves are secured to the side rails, the rungs extend outwardly from the non-flared walk through area. In FIG. 11, an alternative sleeve configuration is shown schematically where the sleeves 121 and 122 are interfitted over flared side rails 21 and 22, respectively, with rungs 15 situated within the flared opening O. In yet another embodiment of the present invention, schematically illustrated in FIG. 12, the walk through section of a job made ladder is shown, wherein the side rails 21 and 22 (typically constructed using 1×1 inch or 4×6 inch wooden side rails) are modified by securely affixing horizontal grasping rungs 15 at locations and intervals in accordance with the present invention. Rungs 15 may be affixed to the side rails using rung-forming device 115 schematically shown in FIG. 13. The rung-forming device is comprised of a screw section 117, stop 118 and rung section 116. When device 115 is screwed into the side rail by driving in screw section 117, stop 118 contacts the side rail, when rung section 116 is properly positioned. It should be apparent to persons of ordinary skill in the ladder art that numerous variations of the preferred embodiments described hereinbefore may be utilized and that, while this invention has been described fully and completely with special emphasis upon preferred embodiments, it should be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. In particular, the architecture of the walk-through section of the present invention can be used advantageously with numerous types of ladders, as will be appreciated by person's of ordinary skill in the ladder art and is not limited to fixed and/or flared walk-through ladders.

A fixed ladder has a first plurality of parallel rungs arranged along a lower section thereof and also has a walk-through section with vertical side rails arranged at the top thereof. A second plurality of parallel rungs is arranged along the walk-through section. This second plurality of rungs is attached at one end to the vertical side rails of the walk-through section and is easier to hold then the vertical side rails if a foot or a climber slips near the top of the ladder while mounting or dismounting at the walk-through section.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates to the field of supports and more particularly to an adjustable support device for mounting a planar object between two opposing surfaces. [0003] 2. Description of the Related Art [0004] In hurricane-prone areas or possibly tornado-prone areas, often when advance notice is provided, windows and doors get covered with plywood to reduce penetration by wind and flying debris. In the past, the plywood was screwed or nailed to the door or window frame and removed when the storm resided. The process of holding the plywood in place and nailing or screwing it to the frame is time-consuming and often required one person to hold the plywood while another person fastens the plywood to the window or door frame. Unfortunately, the screws leave holes where they entered the frame. Even worse, if not pre-drilled, the nails or screws sometimes crack the frame. [0005] An improvement to the process of mounting plywood to the door or window frame is described in U.S. Pat. No. 5,634,618 to Farmer, Jr. et al., which is hereby incorporated by reference. This patent describes an adjustable clip for mounting the plywood between two opposing surfaces (e.g., the inner side surfaces of the door or window frame). The clip described in this patent has a U-shaped “cup” portion into which the plywood fits and a means to apply force to the opposing surfaces which, in one embodiment, is a screw. Unfortunately, this clip is not suitable for a range of materials, being designed to fit only one size of material (e.g., ¼″ plywood). This requires installers to carry different clips for different sizes of plywood or similar material (e.g., ¼″ plywood, ⅜″ plywood, 1 / 2 ″ plywood, 10 mm plastic). Furthermore, after the storm, if plywood is used, it often absorbs moisture. The plywood swells from the moisture and may not fit in the U-shaped cup of this patent. [0006] What is needed is a clip or support that is adjustable to fit many different thicknesses of planar material such as plywood while exerting sufficient force against the inner surfaces of the window or door frame as to hold the planar material in place during severe weather. SUMMARY OF THE INVENTION [0007] In one embodiment, an adjustable support for mounting a substantially planar object between substantially opposed support surfaces is disclosed including a substantially L-shaped base that has a first side and a second side and a clamp that has a side surface and a bottom surface. The clamp is removably attached to the first side of the L-shaped base forming an aperture between the second side of the L-shaped base and the bottom surface of the clamp means. The aperture is adapted to accept the substantially planar object. A pressure screw is threaded through the clamp and passes through an elongated hole in the first side of the L-shaped base. The pressure screw is adapted to apply force against a first support surface to wedge the substantially planar object between the first support surface and a substantially opposed second support surface. [0008] In another embodiment, a system for mounting a substantially planar object between substantially opposed support surfaces is disclosed including a substantially planar object and a first and second opposed support surfaces forming at least a portion of an opening. There is at least one support that has a substantially L-shaped base with a first side and a second side and a clamp with a side surface and a bottom surface. The clamp is removably attached to the first side of the L-shaped base, thereby forming an aperture between the second side of the L-shaped base and the bottom surface of the clamp and the aperture is adapted to accept the substantially planar object. A pressure screw is threaded through the clamp and passes through an elongated hole in the first side of the L-shaped base thereby applying force against a first support surface to wedge the substantially planar object between the first support surface and a substantially opposed second support surface. [0009] In another embodiment, an adjustable support for mounting a substantially planar object between substantially opposed support surfaces is disclosed including a substantially L-shaped base having a first side and a second side and a clamp having a side surface and a bottom surface. The clamp is removably attached to the first side of the L-shaped base thereby forming an aperture between the second side of the L-shaped base and the bottom surface of the clamp, the aperture adapted to accept the substantially planar object. A pressure screw is threaded through the clamp and passes through an elongated hole in the first side of the L-shaped base and is adapted to apply force against a first support surface to wedge the substantially planar object between the first support surface and a substantially opposed second support surface. A first set of serrated edges are on an inside surface of the first side of the L-shaped base where the L-shaped base interfaces with the clamp and are angled towards the aperture. A second set of serrated edge are on the side of the clamp where the clamp interfaces with the L-shaped base and are angled away from the aperture. BRIEF DESCRIPTION OF THE DRAWINGS [0010] The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: [0011] FIG. 1 illustrates a perspective view of a support of the present invention. [0012] FIG. 2 illustrates a rear perspective view of a support of the present invention. [0013] FIG. 3 illustrates an exploded view of a support of the present invention. [0014] FIG. 4 illustrates a view of a door shielded by a planar sheet of material held in place by multiple supports of the present invention. [0015] FIG. 5 illustrates an exploded view of an alternate support of the present invention. DETAILED DESCRIPTION OF THE INVENTION [0016] Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. The support of the present invention is designed to hold in place any conceivable stiff, planar object including wood (e.g., plywood), composite material, plastic (e.g., clear polycarbonate panels or polypropylene panels), glass and metal (e.g., aluminum and galvanize steel). Furthermore, the planar material can be corrugated or accordion style. If corrugated or accordion style, the support of the present invention is preferably deployed at locations along the structural sides of the planar material such that as force is applied, it forms a wedge instead of compressing the corrugations or accordion folds. The support of the present invention holds this planar object securely between two substantially opposed support surfaces by applying traverse pressure between at least one of the support surfaces and the planar object. The support surfaces can be any substantially opposed surface including, but not limited to, two parallel sides of a door frame or window frame. [0017] As will be seen, the supports of the present invention provide an adjustable aperture that can accept and hold a wide range of thicknesses of planar material allowing an installer to need only one type of support for installation of many types of planer material. For example, sheet steel may have a thickness of ¼″ while plywood or polycarbonate panels may have a thickness of ¾″. The supports of the present invention can be adjusted to work equally well with both thicknesses of planar material. Furthermore, often after the storm subsides, the planar material is removed from the structure being protected. If the planar material accepts moisture and expands (e.g., plywood), it is important that the supports adjust to the slightly thicker, off-tolerance planar material. This would not be easy to do with the supports of the prior art. [0018] Referring to FIG. 1 , a perspective view of a support of the present invention is shown. An L-shaped base 22 and clamp 20 are configured to sandwich a planar sheet of material 40 (shown in FIG. 4 ) in an aperture 60 . In a preferred embodiment, base serrations 14 catch and hold clamp serrations 12 , holding the clamp against the planar sheet of material 40 until screws 24 (shown in FIG. 3 ) are inserted and tightened. The base serrations 14 are angled toward the base 22 bottom while the clamp serrations 12 are angled away from the base 22 bottom, thereby engaging with each other to hold the clamp 20 in position with respect to the base 22 while inserting and tightening screws 24 (shown in FIG. 3 ) creating an aperture 60 of desired size. The pressure screw 30 is threaded in preferably the clamp 20 or alternately the base 22 and is tightened to apply pressure against two opposing support surfaces in between which the planar sheet 40 has been inserted as will be shown in FIG. 4 . The two opposing support surfaces are, for example, the inner walls of a door frame or the inner walls of a window frame. [0019] The L-shaped base 22 and clamp 20 are made from any sturdy material, preferably aluminum, steel, stainless steel, ultra-high molecular weight plastic (UHMW) or a structural plastic such as glass-filled polypropylene. [0020] Referring to FIG. 2 , a rear perspective view of a support of the present invention is shown. Shown is the base 22 with elongated screw holes 26 through which clamp screws 24 (shown in FIG. 3 ) pass and another elongated screw hole 32 through which the pressure screw 30 passes. The elongated screw holes 24 / 32 allow movement of the clamp 20 with respect to the base 22 . In this embodiment, serrations 12 / 14 hold the clamp 20 in place with respect to the base 22 while tightening clamp screws 24 , thereby locking the clamp 20 in position with respect to the base 22 . The serrations also provide structural locking between the clamp 20 and the base 22 . [0021] Referring to FIG. 3 , an exploded view of a support of the present invention is shown. Shown is the base 22 with the optional serrations 14 visible from the side only. The optional serrations 12 of the clamp 20 are visible. The pressure screw 30 threads through threads 34 in the clamp 20 and passes through an elongated hole 32 in the base 22 , thereby permitting the clamp 20 to move closer to the base 22 to tightly hold the planar material 40 (not shown). Likewise, clamp screws 24 pass through the elongated holes 26 in the base and into threaded holes 28 in the clamp. The clamp screws 24 hold the clamp 20 and base 22 in relative position after they are adjusted to the desired aperture size. [0022] Referring to FIG. 4 , a view of a door shielded by a planar sheet of material held in place by multiple supports of the present invention is shown. The door is by example. Any opening can be protected with the present invention including, but not limited to, a door and a window. The door has a frame with decorative molding 44 . In this example, a sheet of plywood is fitted within the inside edges of the door frame 47 / 48 and a plurality of supports 10 of the present invention are situated holding the plywood 40 between the clamp 20 and base 22 of the supports 10 and the supports 10 apply pressure to the opposing inside edges of the door frame 47 / 48 by tightening the pressure screws 30 of each support 10 . As shown, supports are positioned on opposite edges of the planar material 40 , which can be any relatively flat and stiff material such as plywood, etc. It is preferred to place the supports 10 at 6 inches from the edge of the planar material 40 and at every 12 inches thereafter. For added strength, supports 10 can be placed on the top and bottom edges of the planar material 40 , thereby exerting pressure on the top and bottom inside walls 48 of the frame 42 . In another embodiment, supports 10 are placed along only one edge of the planar material 40 . For additional protection, the pressure screw 30 can have a protective cup on its end where it interfaces with the door frame 47 / 48 or a thin sheet of a stiff material such as steel can be placed between the end of the pressure screw 30 and the opposed surfaces. [0023] Referring to FIG. 5 , an exploded view of an alternate support of the present invention is shown. Shown is the base 22 with a relatively smooth surface 64 (without serrations) visible from the side only. The face 62 of the clamp 20 is also relatively smooth. Being that the base 22 and the face 62 of the clamp 20 are relatively smooth, friction between these two surfaces holds them in place with respect to each other. In some embodiments (not shown) these surfaces 62 / 64 can be textured or alternately, a gasket can be placed between them to hold the base 22 in place with respect to the clamp 20 . The pressure screw 30 threads through threads 34 in the clamp 20 and passes through an elongated hole 32 in the base 22 , thereby permitting the clamp 20 to move closer to the base 22 to tightly hold the planar material 40 (not shown). Likewise, clamp screws 24 pass through the elongated holes 26 in the base and into threaded holes 28 in the clamp. The clamp screws 24 hold the clamp 20 and base 22 in relative position after they are adjusted to the desired aperture size. [0024] Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. [0025] It is believed that the system and method of the present invention and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.

The present invention is an adjustable support for installing a planar sheet of material between opposed surfaces without the need for piercing the opposed surfaces with nails or screws. The supports provide pressure to wedge the planar sheet, thereby holding it in place during storms, etc. The supports are easily removed. The support has a base and adjustably/removable attached clamp whereby the planar material is sandwiched between the base and clamp. A pressure screw threaded through the clamp and passing through the base is tightened, thereby applying traverse pressure on the planar sheet, wedging it between the opposed surfaces.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION This invention relates to intermediate sleeves for installing piplines by propelling pipes underground as joined together end-to-end, and more particularly to improvements in a sleeve comprising a spigot member and a socket member telescopically fitted together and adapted to be incorporated into an underground pipeline at an intermediate portion thereof. Heretofore it has been practiced to force cast iron pipes, steel pipes or the like directly into earth by a method, which may be termed "propulsion method," for the installation of underground pipelines where there is the necessity of laying the pipeline beneath railways, rivers or roads, or urban areas with heavy traffic where it is impossible to excavate the ground. According to the basic prior art method, a starting pit is first formed in the ground at one end of the pipeline to be installed, and pipes are joined together end-to-end one after another, such that the axially aligned pipe assembly is forced at its rear end into the earth by propelling means, such as hydraulic jacks, provided in the starting pit so as to cause the front end of the pipe assembly to ultimately reach a terminal pit at the other end of the line responsive to progressive lengthening the assembly. However, the propelling capacity of the hydraulic jacks is limited, and the pipe assembly is subjected to an increasing reaction or counterforce with an increase in the overall length of the assembly, with the result that the assembly, when exceeding a certain length, may possibly be buckled or broken down. Thus, there is an inevitable limitation on the length of the pipeline which can be installed only with the use of the propelling means provided in the starting pit. In order to overcome this drawback, heretofore it has been proposed to incorporate a telescopic intermediate sleeve means into the pipe assembly at an intermediate portion thereof and to propel the pipe assembly in the manner of vermiculation by pushing the rear end of the assembly and extending the intermediate sleeve means alternately in repetition while progressively lengthening the pipe assembly. More specifically, the intermediate sleeve means comprises a spigot member, i.e. basically an inner pipe, and a socket member, i.e., basically an outer pipe, which are telescopically fitted together. At an intermediate portion of the pipe assembly, one of the socket members is joined to the rear end of a pipe, with one of the complemental spigot members joined to the front end of the next pipe. The intermediate sleeve means is telescopically extended or stretched by propelling means, such as hydraulic jacks, provided on the inner surface of the sleeve to thereby advance the front segment of the pipe assembly. Subsequently, the rear segment of the assembly following the sleeve is advanced by propelling means in the starting pit while collapsing or contracting the sleeve. The pipe assembly is advanced in its entirety by repeating this procedure. However, the propulsion method employing such previously known intermediate sleeves has some drawbacks notwithstanding its outstanding advantages. First, since the intermediate sleeve eventually constitutes part of the pipeline, there is the necessity of sealing the joint between the spigot member and the socket member of the sleeve after the completion of the propulsion. However, this is very difficult and requires much labor to assemble at the intermediate portion of the underground pipeline a mechanical seal. Such prior art sleeves have been of complex structure such as an inner joint comprising a rubber ring, a divided ring and a pushing ring as illustrated at the left side end in FIG. 3 of the accompanying drawings. Moreover, since the spigot member and the socket member are telescopically fitted together, soil or sand is liable to enter the sliding portion between the members, consequently interfering with or preventing a smooth telescoping movement. Although such intermediate sleeves are usually provided with a cover plate extending from the spigot member intended to prevent the ingress of soil or sand, the prior art seal and plate arrangements generally fail to completely seal off the sliding portion against soil or sand during the repetitive telescoping movement, rendering the members no longer smoothly slidable on each other. Another problem of the prior art systems is encountered with the use of jacks which are usually mounted on the inner peripheral surface of the socket member by suitable brackets. With an increase in the diameter of the pipe, jacks of greater weight are used in an increased number, necessitating increasingly cumbersome procedures for the installation and removal of the jacks. In particular, jacks are difficult to mount on and remove from the upper peripheral portion of the socket member. Indeed, extreme difficulties are experienced in following such prior art procedures at an intermediate portion of the underground pipe assembly. SUMMARY OF THE INVENTION Accordingly, this invention provides for improved intermediate sleeves free of the foregoing disadvantages. An object of this invention is to provide such intermediate sleeve means in the vicinity of its sliding portion with an improved seal of the self-sealing type which, when subjected to the internal pressure of the sleeve, gives the surface pressure required for completely and effectively sealing, rendering the sleeve more effectively usable as part of a pipeline after the completion of propulsion. Another object of this invention is to provide an intermediate sleeve means in which lubricating means are provided whereby a lubricant can be fed under pressure into the variable space adjacent the sliding portion of the sleeve so as to effectively seal off the sliding portion against soil or sand. Still another object of this invention is to provide an intermediate sleeve means having an improved support structure substantially circular in its entirety and rotatable on the inner peripheral surface of the sleeve, the support structure being adapted to support jacks or like propelling means between the structure and the inner peripheral surface and thereby rendering the propelling means mountable with extreme ease at a lower position within an elongated pipe assembly intermediately thereof. These and other objects of this invention will become more apparent from the following description given with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an intermediate sleeve means usable in this invention and comprising a socket member and a spigot member as these members are disassembled from each other; FIG. 2 is a perspective view partly broken away and showing the socket member and the spigot member of FIG. 1 assembled together, the intermediate sleeve means being shown in its wholly collapsed or compressed state, with intermediate jacks omitted; FIG. 3 is an enlarged cross-sectional longitudinal half view showing the intermediate sleeve means in its collapsed or compressed state in operative association with pipes at the opposite ends thereof; FIG. 4 is a fragmentary longitudinal cross-sectional view on an enlarged scale showing a sealing member before the socket member and the spigot member are forceably assembled together; FIG. 5 is a fragmentary longitudinal cross-sectional view on an enlarged scale showing the sealing member compressively extruded after the socket member and the spigot member are assembled together; FIGS. 6(I) to (IV) are diagrammatic longitudinal views showing a pipe assembly incorporating the intermediate sleeve means of this invention in the course of a propelling operation to illustrate the operation in succession; FIG. 6(I) showing the pipe assembly before base jacks and intermediate jacks on the sleeve are operated; FIG. 6(II) showing the pipe assembly when the intermediate sleeve is in its extended state; FIG. 6(III) showing the pipe assembly when the base jacks have been operated; and FIG. 6(IV) showing the pipe assembly with another pipe joined to the near end of the assembly and held at its rear end by the base jacks; FIG. 7 is a perspective view partly broken away and showing the intermediate sleeve and the pipes joined to the opposite ends of said sleeve while the intermediate jacks are out of operation, the view thus corresponding to FIGS. 6(I), (III) and (IV); FIG. 8 is a view similar to FIG. 7, and showing the pipe assembly while the intermediate jacks are in operation, the view corresponding to FIG. 6(II); FIG. 9 is a fragmentary longitudinal cross-sectional view of another intermediate sleeve embodying this invention and provided with means for feeding a lubricant; FIG. 10 is a view, similar to FIG. 9, showing a modification of the intermediate sleeve of FIG. 9; FIG. 11 is a transverse vertical cross-section taken through another form of intermediate sleeve embodying this invention, the view showing in elevation, means for supporting the intermediate jacks; FIG. 12 is an enlarged fragmentary cross-sectional detail view taken along the line XII--XII in FIG. 11; FIG. 13 is another enlarged detail sectional view taken along the line XIII--XIII in FIG. 11; FIG. 14 is a front elevational view showing a unit assembly constituting the jack supporting means of FIG. 11; and FIG. 15 is a side elevational showing the unit assembly of FIG. 14. DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIGS. 1 to 8, in intermediate annular sleeve means 20 according to this invention comprises the combination of a socket member 22 serving as an outer pipe member, and a spigot member 24 slidably fitting into the socket member 22 and serving as an inner pipe member. The spigot member 24 is joined to a pipe 28 disposed to the front thereof toward the direction of propulsion, and the socket member 22 to a rear pipe 30. In the illustrated position, the spigot member 24 has on its left-hand side, i.e., on the front (direction of travel) side, a front spigot end 26 of relatively small wall thickness to be inserted into and joined to the socket end 32 of the pipe 28. The pipe 28 has a recessed portion 34 in the inner peripheral surface of its socket end 32 adjacent the extremity of the end. The recessed portion 34 and the outer peripheral surface of the front spigot end 26 of the spigot member 24 define therebetween a space, which accommodates a rubber ring 35, a divided ring 36 and a pushing ring 38 having bolts 40 screwed therein. The bolts 40, when turned, force the pushing ring 38 inward, causing the divided ring 36 to push the rubber ring 35 into the innermost portion of the space, whereby a mechanical seal is provided as an "internal joint," generally as already known among the prior art devices. The seal affords a watertight joint between the front spigot end 26 of the spigot member 24 and the socket end 32 of the pipe 28. The front spigot end 26 of the spigot member 24 extends into an intermediate portion 46 of increased thickness, with a radial flange 42 formed therebetween. A large number of reinforcing the ribs 44 disposed circumferentially, equidistantly spaced apart are provided between the intermediate portion 46 and the flange 42. Bolts 48 secure the flange 42 to the socket end 32 of the pipe 28 bearing against the flange 42 for transmitting a propelling force and for preventing bending of the pipeline during propulsion. The intermediate portion 46 of the spigot member 24 has substantially the same outside diameter as the flange 42 where the portion adjoins the ribs 44, and extends rearward with a slightly reduced thickness to provide a space 54 for permitting the front end 52 of the socket member 22 to slidably move upon the intermediate portion 46. The intermediate portion 46 further extends into a rear spigot end 50 of still smaller thickness. The inner peripheral surface 55 of the front end 52 of the socket member 22 (FIGS. 3 and 8) and the outer peripheral surface 56 of the intermediate portion 46 of the spigot member 24 are slidable upon each other. Thus, these surfaces 55 and 56 constitute a sliding portion 58. The intermediate portion 46 of the spigot member 24 is provided with a cylindrical cover plate 60 covering the space 54 and having an open rearward end. The cover plate is designed to prevent the ingress of soil or sand. The front end 52 of the socket member 22 extends rearward and is integrally formed with a thicker walled annular portion 62. A groove 64 is formed in the inner peripheral surface thereof for accommodating a rubber ring 66, thus providing a sealing portion. FIGS. 4 and 5 show on an enlarged scale, the sealing rubber ring 66 before and after the spigot member 24 and the socket member 22 are assembled together. The rubber ring 66 is of the self-sealing type capable of giving the surface pressure required for sealing when subjected to the internal pressure of the sleeve. The outer peripheral surface of the rear spigot end 50 of the spigot member 24 is slidably in contact with the rubber ring 66, thus, the rear spigot end 50 must have a length sufficient to be held in contact with the rubber ring 66 at all times whether the intermediate sleeve in in an extended state or in a telescopically compressed or collapsed state. The thicker wall portion 62 of the socket member 22 continues rearwardly into a slightly thinner wall portion 68 which terminates in an integrally formed rearward socket end 70. The rearward socket 70 is adapted to be joined to the front spigot end 31 of the rear pipe section 30. These respective ends 70 and 31 are joined and sealed together in the same manner by the same numbered parts as described for the spigot end 26 of the spigot member 24 and the socket end 32 of the front pipe 28. Thus, this joint will not be described again. Intermediate jacks 72 (FIG. 8) are provided between the rear spigot end 50 of the spigot member 24 and a rib 74 formed on the inner peripheral surface of the partially thinner wall portion 68 of the socket member 22. The rib 74 is adapted to receive the counterforce of the intermediate jacks 72. Indicated at 76 is an annular abutment member disposed on the rear spigot end 50, and indicated at 80 is a rearward abutment and support for the jacks 72, the latter of which are also held by brackets 78. An O-ring 82 fitting around the outer peripheral surface of the front end portion 52 of the socket member 22 seals off the sliding portion 58 from the outside. Another O-ring 84 fitting in the inner peripheral surface of the socket member in the thicker wall portion 62 seals off the sliding portion 58 from the interior of the sleeve and thus protects sealing ring portion 66. The intermediate jacks 72, when in the state shown in FIGS. 6(I) and FIG. 7, are operated by actuating an unillustrated hydraulic pump disposed either inside or outside of the pipe assembly, whereby the spigot member 24 is advanced in the direction of the arrow by a distance corresponding to one stroke a (FIG. 6(II)) of the jacks. The spigot member 24 is guided by the sliding portion 58, with the result that the series of interconnected pipes 28, 28, . . . as connected to the spigot member 24 are propelled forward by distance a (FIG. 6(II) and FIG. 8). At this time, the rearward spigot end 50 of the spigot member 24 moves forward relative to the rubber sealing ring 66, (FIGS. 4 and 5), while being held in sealing contact therewith, since the spigot end 50 has a sufficient length. Subsequently, base jacks 86 (FIG. 6) provided in a rear starting pit 90 are operated, propelling the series of interconnected pipes 30, 30, . . . by a distance corresponding to one stroke b of the base jacks. When the intermediate jacks 72 and base jacks 86 are set for equal strokes, namely, a = b, the operation of the base jacks 86 will telescopically return or collapse the intermediate sleeve to the original state. Consequently, the whole pipe assembly, including the series of pipes 28, 28 . . . , intermediate sleeve 20 and the other series of pipes 30, 30, . . . , is advanced by the above operation a distance corresponding to one stroke of the base jacks 86 (FIG. 6 (III)). During the return or collapse of the intermediate sleeve 20, the spigot end 50, of course, is held in sealing contact with the rubber ring 66. This operation, when repeated, ultimately advances the overall assembly by a distance corresponding to the length of one pipe, whereupon another section of pipe 30a is joined to the rear end of the rearmost pipe 30, and the rear end of the pipe 30a is held in place by the base jacks 86. Subsequently, the foregoing operation is repeated, thereby ultimately forcing the foremost end of the pipe assembly to a terminal pit 91 to complete the run or installation of the pipeline comtemplated. The intermediate jacks 72 are then removed, rendering the intermediate sleeve 20 usable as part of the pipeline as it is. The rubber ring 66, although subjected to sliding contact with the rear spigot end 50 frequently during the telescoping movement of the intermediate sleeve 20, retains its function free of any degradation, since the frequency of the telescoping movement is relatively low. Because the intermediate sleeve described above includes a sealing portion 66 provided between the socket member and the spigot member prior to installation, along with other mentioned seals 82 and 84, the improved intermediate sleeve assembly hereof will be made serviceable as part of the completed pipeline merely by removing the intermediate jacks upon the completion of installation. Thus, the improved intermediate sleeve assembly of this invention eliminates the cumbersome operation which would otherwise be needed to provide a seal at an intermediate portion of the underground pipeline installed. Proceeding to another feature of this invention, the space 54 adjacent the sliding portions of the intermediate sleeve, is filled with a lubricant at all times in order to completely seal off the portion against soil or sand. Thus, to show this feature, reference is made to another illustrative embodiment of intermediate sleeve 120 shown in FIG. 9 wherein the parts corresponding to those in the foregoing embodiment are referred to by the same reference numbers of the latter plus the prefix 100. A space 154 is defined by a cover plate 160, the latter adapted to help prevent the ingress of soil or sand into the outer peripheral surface 156 of an intermediate portion 146 of a spigot member 124. With the intermediate sleeve 120 positioned in its collapsed state, the space 154 has been reduced since the front end 152 of a socket member 122 is shown in the solid-line position, whereas when the spigot member 124 is extended, changing the relative position of the front end 152, the space 154 is enlarged or expands like that shown at 54 in FIG. 8. An aperture 180 extends radially from the inner surface of the member 124 into the space 154 and is provided with an adapter 190 screwed therein for feeding a lubricant 192 to the space 154. A container 191 containing the lubricant 192 is equipped with a suitable pump 193 for injecting the lubricant 192 under pressure into the space 154. The pump 193 is connected to the adapter 190 by a hose 194. The pump 193 may be of the electrically operated type, in which case it has an electrical conductor wire with an end plug 195 for connection to a power supply. When intermediate jacks 172 are operated, advancing the spigot member 124 and increasing the space 154, the pump 193 is actuated at the same time, whereby the lubricant 192 is fed to the enlarging space 154 with sufficient pressure to exclude entry of foreign material. Further, when the base jacks 86 (FIG. 6) are operated, collapsing the intermediate sleeve 120, the pump 193 is disconnected from the power supply, permitting the lubricant 192 to return to the container 191 upon a decrease of the space 154. These operations are repeated with the extension and collapsing of the intermediate sleeve 120. The lubricant 192 thus always fills the space 154 which increases and decreases in size attendant the extension and collapsing of the intermediate sleeve 120. In this manner, it completely prevents the ingress of soil, sand, or other foreign material, into the space 154 and allows the intermediate sleeve 120 to telescopically move smoothly at all times as guided by the sliding portion 158 thereof. FIG. 10 shows a modification of the embodiment shown in FIG. 9, wherein the parts corresponding to those in the previous embodiments are referred to by the same reference numbers plus the prefix 200. The pump 193 of FIG. 9 is replaced in FIG. 10 by a cylinder 295 operable by an intermediate jack 272 to feed a lubricant 292. The lubricant 292 filling the cylinder 295 is placed thereinto through an inlet 296. The cylinder 295 houses a piston 297' which is connected by a rod 297 to a propulsion transmitting cap 298 on the front end of the intermediate jack 272. A hose 294 extends from a forward port 299 in the front end of the cylinder 295 to an adapter 290. The operation of the intermediate jack 272 advances the piston 297' in the cylinder 295, forcing out the lubricant 292 from the cylinder 295 into the space 254 upon the increase of the space 254 due to the outward displacement of a spigot member 224. When the aforementioned base jacks 86 (FIG. 6) are operated, collapsing the intermediate sleeve 220, the intermediate jacks 272 also collapse, thereby helping withdraw and permitting the return of the lubricant 292 from the space 254 into the cylinder 295. FIGS. 11 to 15 show another intermediate sleeve generally designated at 320 embodying this invention and provided with novel means for supporting jacks. The jack supporting means has the following feature. FIGS. 14 and 15 show a unit assembly 303 comprising a pair of front and rear support plates 301a and 301b, respectively, which are substantially in the form of an arcuate sector. A roller 302 is provided between and supported by the plates 301a and 301b. A number of such unit assemblies 303 are arranged and suitably mounted along the inner peripheral surface 322a of a socket member 322 at a suitable spacing. An example of suitable mounting means are support members 305 which have opposite ends thereof interconnect the opposed side ends 304 of the adjacent unit assemblies 303 on the inner peripheral edges thereof, whereby the unit assemblies 303 are fabricated into an annular support structure broadly designated 307 in FIG. 11. Intermediate jacks 372 are supported by the members 305 as disposed between the support members and the inner peripheral surface 322a. The unit assemblies 303 are rollable on the peripheral surface 322a, with the rollers 302 in contact with the surface 322a. The assembled support structure 306 is therefore rotatable on the inner peripheral surface 322a. A pair of bolts 305a for locking the intermediate jack 372 extends through each of the connectors 305 from the center side of the sleeve outward thereof as seen in FIGS. 11 and 13. The distal ends of the bolts bearing against the intermediate jack 273 toward the inner peripheral surface 322a retain the jack 372 in place, free of any backlash and against escape from the support members 305. The locking bolts 305a, when screwed at the distal ends thereof into the outer peripheral surface of the intermediate jack 372, can completely lock the jack in position as illustrated in FIG. 11. Consequently, the intermediate jacks 372 at a lower portion of the sleeve shown in FIG. 11 are supported above the inner peripheral surface 322a of the socket member in suspension. The supporting means will be assembled in the following manner. An intermediate jack support 380 (FIG. 12), divided into three or four portions in its circumference, is secured by bolts 381 to a rib 374 on the socket member 322 for receiving the counterforce of the intermediate jacks. Projecting inwardly from the inner peripheral edge of the jack support 380 are brackets 383 for temporarily holding the unit assemblies 303 to be mounted. Corresponding to the brackets 383 are brackets 307 (FIGS. 12, 14 and 15) projecting from the inner peripheral edges of the support plates 301a and 301b of the unit assemblies 303. The unit assemblies 303 are arranged along the inner peripheral surface 322a of the socket member 322 as stated before, and are held to the brackets 383 by bolts 308 and nuts 309 (FIG. 12) extending through the brackets 383 and 307. The support members 305 are then secured, each at its opposite ends, to the opposed side ends 304 of the adjacent unit assemblies 303 on the inner peripheral edges thereof, whereby the unit assemblies 303 are interconnected to one another into the aforementioned support structure 306 for mounting within the socket member 322. The bolts 308 and nuts 309 (FIG. 12) are then removed from the assembled support structure 306 thus rendering the structure 306 freely rotatable on the inner peripheral surface 322a of the socket member 322. At a lower portion of the socket member, an intermediate jack 372 is then inserted into the space defined by the cradle-like support members 305 between two adjacent unit assemblies 303 and by the inner peripheral surface 322a, being inserted through a space between the members 305 and the rear end of an unillustrated spigot member. The locking bolts 305a are thereafter rotated so as to push the intermediate jack 372 toward the inner peripheral surface 322a, whereby the jack 372 is held in place against any displacement. This novel arrangement permits the intermediate jacks 372 to be mounted in place at the lower peripheral position, whereupon the support structure 306 is suitably rotated sufficiently to bring an adjacent upper portion thereof to the lower position, where additional intermediate jacks 372 are progressively installed in the same manner as above. Thus, all the intermediate jacks 372 to be arranged over the entire inner circumference of the socket member 322 can be more readily installed in place at the lower portion of the socket 322. The intermediate jacks 372 are removable by following the above procedures in the reverse order. The use of the support means greatly facilitates the mounting and removal of the intermediate jacks, without incurring potential hazard of dropping a jack during mounting. The unit assemblies 303, which weigh considerably less than the jacks, are easy to install within the socket member 322. Accordingly, the operation of mounting and dismounting of the jacks, including the fabrication of the supporting means, can be carried out with an exceedingly high efficiency heretofore unattainable.

An improved form of intermediate sleeve for installing a pipeline by forcing pipes into earth, incorporating the sleeve into the resulting pipe assembly at an intermediate portion thereof, and pushing the rear end of the pipe assembly and telescopically extending the sleeve alternately in repetition to thereby propel the assembly. The intermediate sleeve comprises a socket member, a spigot member slidably fitting in the socket member and includes a sealing portion in the vicinity of a sliding portion between the members. The intermediate sleeve is usable as part of the pipeline after the completion of the propulsion without the necessity of providing any additional special seal. The intermediate sleeve can be equipped with a feeder device for feeding a lubricant into the sliding portion and for withdrawing the same therefrom during collapsing movement to completely prevent the ingress of soil or sand into the sliding portion. The intermediate sleeve can be further provided with a special jack supporting structure by which intermediate jacks are readily progressively mountable on circumferentially spaced portions of the sleeve via progressive mounting thereof at its lower portion.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION This invention relates to door latches, and more specifically to a rotary latch for standard doors in houses and other buildings. RELATED CASE This application is a continuation-in-part of application Ser. No. 577,180, filed May 14, 1975 now abandoned. BACKGROUND OF THE INVENTION The design of latches for doors has taken a variety of forms, the most common being the horizontal spring bolt which is depressed by the striker plate and then pops into an opening in the striker plate when the door is fully closed. This type of spring latch has a number of disadvantages in that it is difficult to adjust except by repositioning the stop or the striker plate on the jamb, giving rise to the problem of a door which rattles. Unless some positive latching control is used, the spring bolts can be easily wedged or deflected by a wire, plastic card, or other metal devices to permit the door to be opened even though the mechanism controlling the latch is locked. This has given rise to the use of "dead bolt" type latches particularly for outside doors to provide a positive locking action. Various types of rotary latches have heretofore been proposed, particularly for use with automobile doors where alignment problems and other safety considerations impose special requirements. However, such rotary latch arrangements have generally been too complicated or expensive, or difficult to install to be useful with common household doors. A rotary door latch mechanism, for example, as is described in U.S. Pat. No. 1,711,213 requires the door to close against a stop. It does not provide a flush, smooth external appearance either with the door open or closed, since the keeper requires a striking lip which must project toward the door and requires an exposed opening in the jamb adjacent the door. SUMMARY OF THE INVENTION The present invention provides a rotary type latch for use with household doors which provides a number of advantages over conventional spring bolt or dead bolt latches commonly found in use, yet is simple and therefore less costly to manufacture and also is easy to install. The rotary latch is designed to interface with existing door knob controls and standard locking systems. It provides a positive latching device which cannot be forced open by plastic cards or other metal devices inserted between the door and the jamb. The latch is relatively silent in operation and requires a minimum of physical effort to operate the latch. The latch is capable of accommodating a relatively large tolerance range in the spacing between the edge of the door and the jamb and yet provides a smooth external edge with a flush face plate on the jamb. These and other advantages are achieved by providing a door closure in which a striker plate mounted on the jamb has a pair of openings forming a vertically extending post between the openings. A latch assembly mounted in the opposing edge of the door has a rotary latch member pivotally supported on a vertical axis. The latch member is rotated between open and closed positions, first by a portion projecting beyond the edge of the door which engages the edge of the striker plate as the door is moved towards the closed position, and then by a notch in the latch member which is rotated into engagement with the post. When the door is in the fully closed position, a releasable detent locks the rotary latch member against further rotation in either direction. The engagement of the latch member with the post secures the door in the closed position. On release of the detent and opening of the door, the rotary latch member returns to its initial open position by the action of a spring. The latch assembly can be inserted in a round bore drilled in the edge of the door, making the assembly easy to install. The rotary latch uses a face plate that is mounted flush with the opposing jamb, giving a smooth, attractive appearance when the door is either in the closed or open positions. DESCRIPTION OF THE DRAWINGS For a better understanding of the invention reference should be made to the accompanying drawings, wherein: FIGS. 1, 2, and 3 are top views in section showing the latch in the open, partially closed, and fully closed positions; FIG. 4 is a sectional view taken substantially on the line 4--4 of FIG. 3; FIG. 5 is an elevational view of the striker plate; FIG. 6 is a side elevational view partly in section of an alternative embodiment of the invention; FIG. 7 is an edge view of a door with the latch installed; FIGS. 8A and 8B are top views in sections showing the latch in the open or unlatched position and the latched position, respectively; FIG. 9 is a sectional view taken substantially on the line 9--9 of FIG. 6; and FIG. 10 is a perspective view of the rotary latch member. DETAILED DESCRIPTION Referring to the drawings in detail, the numeral 10 indicates generally a door, such as a conventional panel or hollow core door commonly used in building construction. The door is hinged along one edge by suitable hinges 12 to the door frame 14. The opposite side of the door frame includes a jamb 16. The edge of the jamb, at the desired height above the floor at which the latch is located on the door, is recessed at 18, and a striker plate 20 is secured to the jamb so as to bridge the recess 18. As shown in FIG. 5, the striker plate is provided with a pair of rectangular openings 21 and 22, a post 24 being formed between the two openings which extend vertically. The striker plate 20 has a curved lip or edge 26 which is turned in toward the jamb for engaging the latch when the door is moved toward the closed position. The door directly opposite the striker plate 20 is also provided with a recess 30 which is semi-cylindrical in shape and having an inwardly directed passage 32 which intersects a large circular bore 34 passing through the face of the door. A latch assembly, indicated generally at 36, is mounted in the recess 30, the latch assembly having a facing plate 38 which is mounted flush with the edge surface of the door. The assembly 36 includes a housing formed from an upper wall 40 and lower wall 42 which are secured in parallel relation to the face plate 38. The housing extends through the bore 34 and terminates in an end wall 44 which is substantially tangent to the surface of the bore 34 in the door. The top and bottom walls 40 and 42 are joined by sidewalls 48 and 50 which include arcuate portions 52 and 54 that terminate at the face plate 38. The arcuate portions 52 and 54, together with the top and bottom walls 40 and 42, form a semi-cylindrical chamber in which is mounted a rotary latch member 56. The latch member 56 rotates about a vertical axis on a shaft 58, the ends of which are journaled in the top and bottom walls 40 and 42. A return spring 62 has turns extending around the shaft 58 with one end anchored to the rotary latch member 56 and the other end anchored to the frame. The spring 62 urges the rotary latch member 56 to rotate in a counterclockwise direction as viewed in FIGS. 1-3. This brings the rotary latch member 56 against a stop 64 when the door is in the open position, as shown in FIG. 1. In this position, the rotary latch member has a flat surface 66 which is flush with the face plate 38 and radially extending surface 68, forming a large obtuse angle to the surface 66. The surface 68 is defined by a portion 70 which projects outwardly of the face plate 38 in position to engage the lip 26 of the striker plate 20 when the door is moved toward a closed position. The latch member has a radial notch 72, the centerline of the notch passing through the axis of rotation of the latch member. The notch 72 is immediately adjacent to surface 66, which is parallel to the sides of the notch. Where the side of the notch joins the outer periphery adjacent the surface 66, it is rounded off, as indicated at 74. When the door 10 is moved to the closed position and the surface 68 comes in contact with the lip 26, the latch member 56 is caused to rotate in a clockwise direction against the action of the spring 62. This causes the rounded edge 74 at the outer end of the notch 72 to be rotated into the opening 22 in the striker plate. As the door continues to close, the post 24 engages the notch 72, as shown in FIG. 2. When the door is fully closed, the latch 56 has been rotated through substantially 90° to the position shown in FIG. 3. In this position, a detent mechanism, indicated generally at 76, engages a notch 78 on the edge of the rotary latch member 56, locking the rotaty latch member against rotation in either direction. Thus the door is secured in position by the engagement between the notch 72 and the post 24. A stop 79 limits rotation of the latch member in the clockwise direction. The detent mechanism 76 includes a plunger 80 which is joined at one end to a transverse shaft 82 on which are journaled a pair of rollers 84 that are in rolling engagement with the peripheral surface of the latch member 56. The plunger 80 extends through an opening in the end member 44 of the frame, and a coil spring 86 urges the plunger toward the rotary latch member 56. The cross-sectional shape of the plunger and shape of the opening are preferably rectangular to prevent rotation of the plunger. The outer ends of the shaft 82 engage slots 88 in the top and bottom walls 40 and 42 for guiding the plunger. The rollers 84 engage a peripheral cam surface 85 extending around the back portion of the latch member 56. The radial distance of the surface 85 from the axis of rotation increases toward the notch 78, which acts to compress the spring 86 and gradually increase the resistance to rotation of the latch member as the door approaches the fully closed position. The plunger 80 has a T-shaped end 90 extending into the bore 34. This enables the latch to be used with a conventional door knob assembly 92 inserted in the bore 34 after the latch assembly 36 is mounted in position. The door knob assembly includes a slide member 94 having a pair of fingers 95 which extend around the back side of the T-shaped end 90 of the plunger 80 when the door knob assembly 92 is inserted in the bore 34. The door knobs rotate an arcuate member 96, the ends of which engage a cross portion 98 of the slide member 94. Thus rotation of the arcuate member 96 in either direction urges the slide member against a spring 100 and, by means of the fingers 95, thereby moves the plunger 80 to release the detent and unlatch the door. An alternative embodiment of the present invention is shown in FIGS. 6 through 9. The latch assembly, indicated generally at 110, is arranged to fit into a cylindrical bore 112 drilled into the edge of the door, the diameter of the bore 112 being somewhat smaller than the thickness of the door. The bore 112 intercepts a second bore 114 of larger diameter drilled in the face of the door for receiving a conventional door knob assembly (not shown). The rotary latch assembly has a housing including a face plate 116, flat top and bottom walls 118 and 120 and cylindrically contoured side walls 122 and 124 of slightly smaller radius than the bore 112. Thus the housing can be readily inserted in the bore. The face plate 116 is recessed in the edge of the door and secured in place by suitable wood screws at the four corners of the face plate, as indicated at 126. The housing has a back plate 128 which is held in place against the back edges of the side walls 122 and 124 of the housing by providing tabs 130 extending from the edges of the flat top and bottom walls. The tabs 130 are crimped over after assembly to lock the back plate in place. A plunger 132 extends through an opening in the back plate 128 and forms a T-connection with a latch pin 134. The ends of the latch pin 134 are guided in slots 136 and 137 in the top and bottom walls 118 and 120. The outer end of the plunger 132 has a T-shaped end 140 adapted to engage a conventional door knob assembly (not shown). A concentric coil compression spring 142 urges the latch pin toward a rotary latch member 144. The rotary latch member 144 projects through an elongated opening 146 in the face plate conforming to the interior cross sectional shape of the housing. A hinge pin 148 extends through the rotary latch 144, the pin being journaled in aligned holes in the top and bottom walls 118 and 120 of the housing. The rotary latch 144 has the axis of rotation offset from the vertical centerline of the housing, as viewed in FIG. 7. The rotary latch rotates against the urging of a spring 145 about the offset hinge pin 148 through substantially 90° when going from the unlatched to the latched position, as shown respectively in FIGS. 8A and 8B. This causes the inner end 150 of a notch 152 in the rotary latch to move through an arc. Thus the inner edge 150 moves outwardly beyond the face plate 116 toward a post 154 on the striker plate 156 mounted in the opposing jamb 157. The notch 152 itself is elongated with a pair of parallel flat surfaces 158 and 160, the surface 160 being curved outwardly, as indicated at 162, to an intersection with a flat surface 164 that normally is flush with the face plate when the rotary latch is in the unlatched position, as shown in FIG. 8A. The surface 158 extends radially outwardly from the pivot axis a greater distance than the surface 160 to insure that the post can easily move into the notch 152 as the latch member 144 rotates, as hereinafter described. The rotary latch is rotated about the hinge pin 148 by engagement between a retractable nose member 166 coming in contact with a lip 168 of the striker plate 156 which projects beyond the front edge of the jamb. The nose portion 166 is substantially wedge-shaped and fits in a slot 169 in a projecting portion 171 of the rotary latch member 144. The retractable nose member 166 is pivotally supported on the hinge pin 148. The nose member 166 is normally urged outwardly by a compression spring 170. In its outermost position it provides a wedging surface 172 which projects at a substantial angle outwardly from the flat surface 164 of the latch member. When retracted it is flush with a surface 174 extending outwardly at a substantially smaller angle to the surface 164. The retractable nose permits a much greater tolerance in the gap between the edge of the door and the adjacent jamb and striker plate. If the gap is very small, as the latch begins to rotate on contact between the surface 172 and the lip 168, the surface 164 will rotate toward and come in contact with the inner guide 176 of the striker plate. This prevents the latch from rotating too far, but causes notch 152 to be guided toward and into engagement with the post 154. With rotation the outer end of surface 158 engages the posts and guides the post on into the slot. The retractable nose member 166 will be moved into the slot 169 against the spring 170 by the lip 168 even though the rotation of the latch is restricted by the surface 176, preventing any binding. If the gap is very wide, the retractable nose member 166 insures that the rotary latch 144 will still be rotated sufficiently by engagement with the lip 168 to rotate the point formed by the radius surface 162 past the post 154 so that the notch 152 still receives the post 154. When the door is fully closed, the latch 144 is rotated to the position shown in FIG. 8B in which the latch pin 134 drops into a notch 173 in the latch 144. This secures the door in the closed position until the latch pin 134 is retracted to release the latch. From the above description it will be seen that a rotary latch is provided which can be easily installed by merely drilling or boring holes in the door. The latch provides positive latching action over a wide variation in spacing between the edge of the door jamb. The slot and post form a snug fit to eliminate any rattle even though the door stop is not properly fitted. The rotary latch can be used with any standard door knob assembly presently available on the market.

A latch carried by a door is rotatable about a vertical axis. The rotary latch member has a portion which engages a stationery striker plate on the door jamb which rotates the latch as the door moves to the closed position. Rotation of the latch causes a notch in the latch to engage either side of a post in the striker plate. The latch member continues to rotate until the door is fully closed by the interaction of the post with the notch. A releasable detent member locks the rotary latch against further rotation in either direction when the door reaches the fully closed position.

You are an expert at summarizing long articles. Proceed to summarize the following text: This is a division of application, Ser. No. 034,171, filed Apr. 26, 1979, now U.S. Pat. No. 4,316,715. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to concrete screeds, and more particularly, open frame vibratory screeds. 2. Description of the Prior Art A wide variety of vibrating concrete screeds are disclosed in the prior art. An open frame, vibrating screed is manufactured by the H. Compton Company of Conroe, Tex., and includes a plurality of pneumatic vibrators mounted at intervals on front and rear screed blades. This screed is fabricated in variable length sections, is translatable over a freshly poured concrete surface by a pair of winches and can be adjusted to provide a variable contour for the surface of the concrete being screeded. Another related concrete screed is manufactured by AWS Manufacturing, Inc. of Naperville, Ill. The AWS concrete screed also includes a wall mounting bracket attachment which is bolted to an end bracket of the screed and includes a single length of angle iron which engages the top and side surfaces of a 2×4 wall mounted guide rail. U.S. Pat. No. 4,030,873 (Morrison) discloses a multi-element concrete screed having variable length elements and a rotating shaft which extends along the length of the screed for imparting uniform vibrations to the front and rear screed blades. All of the above described concrete screeds are vertically supported above opposing, parallel oriented side forms. U.S. Pat. No. 3,110,234 (Oster) discloses a concrete screed having vertically adjustable blades which are translatable along parallel oriented rails. U.S. Pat. No. 3,435,740 (McGall) discloses a concrete screed including a hand operated winch for laterally translating the screed and a turnbuckle system for adjusting the concrete surface contour formed by the various sections of the screed. U.S. Pat. No. 2,542,979 (Barnes) discloses a concrete screed having an inverted T-shaped screed blade and electric motor for imparting a vibratory motion to the screed blade. U.S. Pat. No. 3,883,259 (Berg) discloses another concrete screed having parallel oriented blades and means for imparting vibratory motion to the blades. The following U.S. patents disclosed other concrete screed configurations: U.S. Pat. Nos. 2,372,163 (Whiteman); 1,386,348 (Maxon); 2,866,394 (Smith); 3,008,388 (Nave); 4,073,593 (Storm); 3,095,789 (Melvin); 3,523,494 (Kraemer); 2,219,247 (Jackson); 3,113,494 (Barnes); 2,693,136 (Barnes) and 4,105,355 (King). SUMMARY OF THE INVENTION The present invention contemplates a vibrating concrete screed system including a fixed blade extension bracket, an adjustable blade extension bracket, a detachable guide bracket, a detachable pan float finisher and a center mounted winch attachment. Each of these attachments can be readily coupled to a screed which converts freshly poured concrete freshly poured concrete lying in an area between opposing side forms into a smooth, finished concrete surface. The screed of this system comprises a frame having first and second ends, front and rear screed blades coupled in a spaced apart relationship to the lower portion of the front and rear of the frame to shape the upper surface of the concrete, and first and second end brackets which are coupled to the first and second ends of the frame. The fixed blade extension bracket can be coupled to either or both ends of the screed and includes a front blade extension which is coupled in alignment with the front screed blade to extend the overall length of the front blade by a predetermined desired amount. The fixed blade extension bracket also includes a rear blade extension which is coupled in alignment with the rear screed blade to extend the overall length of the rear blade by a predetermined desired amount. The adjustable blade extension bracket can be coupled to either one or both of the end brackets and includes horizontally adjustable front and rear blade sections, and means for coupling the front and rear blade sections to the first and second side members of an end bracket to permit the adjustable end bracket to be coupled at selected vertical positions to the end bracket while maintaining the front and rear blade sections in parallel alignment with the front and rear screed blades. The detachable guide bracket functions to guide one end of the screed along a wall mounted, horizontally oriented guide member. The guide bracket includes a first vertically oriented side member, a second vertical oriented side member, means for detachably coupling the first and second side members to an end bracket of the screed, and guide means laterally extending from the first and second side members for contacting the guide member to maintain the screed at a predetermined desired vertical position as the guide means is laterally translated along the length of the guide member. The detachable bottom pan is positioned between the first and second end brackets of the screed and includes a front edge which is coupled to the front screed blade and a rear edge which is coupled to the rear screed blade. Certain embodiments of the screed of the present invention include first and second winches which are coupled to the first and second end brackets and include lines extending from the first and second winches which are coupled to a stationary object for exerting a traction force on the first and second end brackets of the screed when the lines are reeled in by the first and second winches. A detachable, center mounted winch may also be provided. The center mounted winch attachment includes a line extending from the winch to a stationary object for permitting the center mounted winch to exert a traction force on the central section of the screed to permit uniform translation of the entire length of the screed. DESCRIPTION OF THE DRAWINGS The invention is pointed out with particularity in the appended claims. However, other objects and advantages together with the operation of the invention may be better understood by reference to the following detailed description taken in connection with the following illustrations wherein: FIG. 1 is a perspective view of a two section screed in accordance with the present invention. FIG. 2 is a partial elevational view of the left hand portion of the screed illustrated in FIG. 1. FIG. 3 is an enlarged perspective view of the means for adjusting the contour of the front and rear screed blades. FIG. 4 is an enlarged view of the hardware utilized to join the blade sections of adjacent screed sections. FIG. 5 illustrates the structure and positioning of the center mounted winch attachment. FIG. 6 is a perspective view illustrating a blade extension bracket in accordance with the present invention, and indicating the manner in which the blade extension bracket is coupled to the screed. FIG. 7 illustrates the adjustable blade extension bracket of the present invention and the manner of coupling this bracket to an end bracket of the screed. FIG. 8 is a perspective view of a detachable guide bracket in accordance with the present invention. FIG. 9 illustrates the manner of attaching the detachable guide bracket to an end bracket of the screed and the relative positioning of the guide bracket with respect to a wall mounted guide rail. FIG. 10 illustrates a blade extension bracket having a shorter length blade extension than the blade extension bracket illustrated in FIG. 6. FIG. 11 is a partial sectional view of the adjustable blade extension bracket shown in FIG. 7. FIG. 12 is an elevational view of the screed illustrated in FIG. 1, taken along section line 12--12. FIG. 13 is a view from above of the screed illustrated in FIG. 12, taken along section line 13--13. FIG. 14 is an enlarged view of a section of the screed shown in FIG. 13, particularly illustrating the structure and relative orientation of the truss members of the screed. FIG. 15 is a sectional view of the screed illustrated in FIG. 12, taken along section line 15--15, particularly illustrating the manner in which the detachable bottom pan is coupled to the front and rear screed blades. FIG. 16 illustrates the detachable pan float finisher of the present invention. FIG. 17 is a view from above of the adjustable extension bracket shown in FIG. 7. DESCRIPTION OF THE PREFERRED EMBODIMENT In order to better illustrate the advantages of the present invention and its contributions to the art, a preferred hardware embodiment of the inventive system will now be described in some detail. Referring now to FIGS. 1 and 2, the vibrating concrete screed which forms the primary element of the screed system will be described. In many figures numerous support structures have been delected in the interst of more clearly illustrating other elements of the invention. The specific configuration of the open frame support structure will be fully described in connection with FIGS. 12, 13 and 14. A horizontally oriented air transport pipe 10 extends between first and second end brackets 12 and 14. Two L shaped blades coupled back to back form a Tee-shaped front screed blade 16. An L-shaped rear screed blade 18 is also coupled to the first and second end brackets 12 and 14. In the preferred embodiment the screed is fabricated in 5 foot and 71/2 foot lengths, any combination of which can be joined together to form a screed having a length reasonably close to the desired length. FIG. 4 illustrates the manner in which a splice plate and a plurality of securing means such as nuts and bolts may be used to couple together abutting ends of each screed blade section. FIG. 3 illustrates the structure utilized to coupled adjacent sections of air transfer pipe 10 to form a single structural element. Air transfer pipe 10 forms an air tight conduit which supplied a source of air under pressure along the entire length of the screed. The air transfer pipe junction illustrated in FIG. 3 comprises a threaded coupling unit 20 having left hand threads on one end and right hand threads on the other end which is rotatably adjusted to provide the desired angle of incidence between adjacent screed section. This adjustment provides the desired contour on the upper surface of the concrete being screeded. A jam nut 22 locks coupling unit 20 in the desired position. Referring now to FIGS. 1 and 2, a high volume air compressor unit is coupled by a crow's foot coupling unit 24 to inline lubricator 26. An air control valve 28 and an air pressure gauge 30 are coupled between coupling unit 24 and filter 26. Lubricator 26 and its associated hardware is detachably coupled to air transfer pipe 10 by a pair of spring clips of the type indicated by reference number 32. A flexible air hose 34 is coupled at one end to lubricator 26 and at the other end to air transfer pipe 10 by crow's foot coupling unit 36. A plurality of penumatic vibrators are coupled at intervals along the length of front screed blade 16 and rear screed blade 18. The pneumatic vibrators are coupled to the vertical face of rear screed blade 18 and to the rear horizontally oriented face of front screed blade 16. An air hose, such as air hose 40, couples each vibrator unit to the source of air under pressure within air transfer pipe 10. The vibrators are generally staggered front to back and are coupled at 30 inch intervals. A vibrator is coupled to the front and rear screed blade 30 inches from both end brackets 12 and 14 to maximize vibration of the screed in the vicinity of the side forms. Each air vibrator unit 38 includes a vertically displaceable piston and a pair of air discharge ports in the side of the cylinder wall. The piston within each cylinder vibrates at between 6000 to 8000 cycles per minute when air at approximately 40 PSI is supplied. Air vibrator units of the type used in connection with the present invention are well known to those skilled in the art and are commercially available. The complete screed unit is translated along the upper surface of opposing side forms 42 and 44 by actuation of winches 46 and 48. These winches can be power driven or manually operated devices. A cable 50 from each winch passes around a pulley 52 which is coupled by bolt through the vertical face of front screed blade 16 to the front vertically oriented member of end bracket 12. The free end of cable 50 is coupled to a stationary object generally aligned with side form 42. To prevent bowing of the central portion of a screed having a length around 60 feet or more, a center mounted winch assembly of the type depicted in FIG. 5 is generally utilized. A center mounting bracket 54 of a configuration virtually identical to end brackets 12 and 14 is coupled at the junction between two adjacent screed units in the center of the assembled screed. An additional winch 56 is coupled to the upper portion of bracket 54. The cable extending from winch 56 passes through a pulley in a manner similar to that described in connection with the pulleys for outboard winches 46 and 48. Workmen operate winches 46, 48 and 56 at an equal rate to uniformly translate the screed in the desired direction to prevent bowing of the central portion of the screed. Since it is frequently desirable to more precisely tailor the length of a concrete screed to match the distance between side members 42 and 44 than is permitted by the previously described 5 foot and 71/2 foot screed sections, blade extension brackets of various fixed lengths have been provided as is illustrated in FIG. 6 and 10. To incorporate a blade extension bracket 58 into the screed, one or both of the end brackets 12 and 14 are removed from the screed. Extension bracket 58 is then coupled by securing means such as nuts and bolts to the front and rear screed blades. Each extension bracket includes a front blade extension 60 and a rear blade extension 62. As can be seen from FIGS. 6 and 10, the length of the front and rear blade extensions can be fabricated in any desired length. In the system of the preferred embodiment, three blade extension brackets having lengths of 6, 12 and 18 inches are provided. Blade extension bracket 48 also includes a horizontally oriented strut 64 which extends between the end portions of blade extensions 60 and 62 to maintain a predetermined fixed spacing therebetween. Angled support struts 66 and 68 are coupled respectively to the outer end of front blade extension 60 and rear blade extension 62 and to the vertically oriented members of blade extension bracket 48. If desired, vibrators may be coupled to the blade extension bracket. Referring now to FIGS. 11 and 17, a vertically and horizontally adjustable blade extension bracket 70 will be described. A bracket of this type is particularly desirable when it is necessary to form a step or sidewalk adjacent to the roadbed or warehouse flooring which is being formed by the remainder of the screed. The adjustable blade extension bracket 70 is coupled to the parallel oriented, vertically extending side members 72 and 74 of end bracket 12. Bracket 70 can be divided generally into a telescopically adjustable first section 76 which permits adjustment of the lateral extension of section 76 with respect to end bracket 12. A second vertically adjustable section 78 permits the entire unit to be adjustably secured to side members 72 and 74 of end bracket 12. Section 78 includes a pair of horizontally oriented channel members 80 and 82 which are dimensioned to permit the two telescopically adjustable legs of section 76 to be readily laterally translatable within the interior of sections 80 and 82. Securing means in the form of an adjustable bolt, such as bolt 84, are provided in the sides of channels 80 and 82 to clamp section 76 in the desired lateral position. The horizontal distance between the interior portions of channels 80 and 82 is just sufficient to permit them to be fitted within the interior walls of side members 72 and 74 of end bracket 12. A horizontally oriented support strut 86 is of a length equal to the horizontally oriented support strut 88 of end bracket 12. The distance between the interior surfaces of channels 80 and 82 is equal to the overall width of strut 88. Pairs of parallel aligned steel plates, such as plate 90 are coupled by securing means, such as a plurality of nuts and bolts, at one end to each vertically extending strut 92 of bracket 70. A second plurality of securing means, such as another set of nuts and bolts, passes behind side member 72 and serves to hold the two parallel aligned steel plates 90 together around side member 72. A third set of bolts, such as bolt 94, are threadably coupled to the exterior of steel plate 90 and when tightened serve to clamp bracket 70 in a predetermined desired vertical position along side members 72 and 74. In the above described manner structure is provided which permits vertical and lateral adjustment of the adjustable blade extension bracket 70. Referring now to FIGS. 8 and 9, a detachable guide bracket forming a portion of the system of the present invention will now be described. Guide bracket 96 includes vertically oriented members 98 and 100 and a horizontal member 102 from which a group of three lips, such as lip 104, extend to form a three-sided rectangular aperture fro accomodiating the upper horizontally oriented strut of end bracket 12. A pair of parallel oriented rectangular steel plates, such as plate 106, are secured to the lower portion of each side member 98 and 100. As guide bracket 96 is rotatably fitted to end bracket 12, each pair of plates coupled to the lower portion of side members 98 and 100 slip around the lower portion of the side members of end bracket 12. Securing means, such as a pair of nut/bolt units 108, is provided to draw the parallel plates together to securely clamp guide bracket 96 to end bracket 12. Additional bracket structure of the type illustrated extends outward from the side of guide bracket 96 and includes a pair of curved, horizontally oriented guide faces 110 and a pair of curved, vertical oriented guide faces 112. Guide faces 110 and 112 are configured to slide along the exposed horizontal and vertical faces of a 2×4 guide member 114 which is secured to a wall 116. The weight of one end of the screed is thus supported by guide rail 14 as the screed is translatable along the length of the concrete which is being shaped. Referring now to FIGS. 12, 13, 15 and 16, a detachable aluminum pan float finisher is disclosed. Pan 118 includes a plurality of apertures in alignment with the horizontal sections of the front and rear screed blades. Securing means are passed through the plurality of apertures in order to couple pan 118 to the lower surface of front and rear screed blades 16 and 18. The pan float finisher includes upward curved front and rear end sections to assist in smoothing freshly poured concrete. Referring now to FIGS. 12, 13 and 15, pan float finisher 118 is shown coupled to the screed. These figures together with FIG. 14 also clearly illustrate the totality of the network of struts which form the open frame for the screed of the present invention. Similar strut elements in each figure are referred to by the same letter/number designator, e.g. strut A1 in FIG. 12 corresponds to strut A1 in FIG. 14. Each strut is coupled at both ends by welded junctions to the remainder of the screed and to the various adjacent other struts. It will be apparent to those skilled in the art that the disclosed vibrating concrete screed system may be modified in numerous ways and may assume many embodiments other than the preferred forms specifically set out and described above, Accordingly, it is intended by the appended claims to cover all such modifications of the invention which fall within the true spirit and scope of the invention.

A triangular truss screed includes first and second vertically oriented end brackets coupled to the first and second ends of the screed frame. Each end bracket includes front and rear vertically extending, spaced apart side members. A detachable guide bracket can be coupled to one of the screed end brackets for the purpose of supporting and guiding one end of the screed along a horizontally oriented guide member coupled to the wall of a building at a vertical position well above the concrete surface. The guide bracket includes first and second spaced apart side members which are detachably coupled to a screen end bracket. The guide bracket includes guide elements which laterally extend from the guide bracket to engage the wall-mounted guide member.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE DISCLOSURE It is customary to perforate a completed oil well to obtain production from the adjacent formations. The ideal perforation is relatively large in diameter and penetrates as deep as possible. A large and deep hole best provides a flow path from the producing formation. This flow path must typically extend from the formation through the cement around the casing and also through the casing. A relatively large and deep perforation is therefore desirable to reduce pressure drop along the flow path to assure proper production from the formation into the borehole for collection in the cased well. There are however, physical constraints on obtaining such large and deep perforations. Ordinarily, a tubing string is placed in the well within the casing. The size of the tubing string limits the size of the through-tubing perforating gun assembly. A popular tubing string has a nominal size of 23/8" which provides an ID of 1.995". When this tubing string is installed along with the necessary completion components (e.g., nipples, sliding sleeves, safety valves, etc.), the minimum ID clearance is normally decreased from the nominal measure just stated. It is not uncommon to have an ID of 1.875" or even as low as 1.781". Given these dimensions, the diameter of the perforating gun assembly is thus limited. Common through-tubing perforating gun assemblies are typically 1 9/16" OD with a hollow carrier, or 1 11/16" OD if using an expendable carrier. Many circumstances prevent the use of an expendable carrier, including operation in a well that is unduly hot, one with hostile downhole fluids, or where the casing is weak or unsupported. In the event that a 1 9/16" OD hollow carrier gun is required, it typically is installed with a 3.0 gram explosive charge. Such an explosive charge will provide (in accordance with the API RP-42 concrete test) an entrance hole of 0.24" diameter and penetration of 6.17". Regrettably, firing of the perforating gun provides swelling to about 1.68" OD. While this swelling can be acceptable in some circumstances, a larger and deeper perforation obtainable by using larger charges is much more desirable. Consider the possibility of using shaped charges of the size normally conducted in a 2" OD gun. These shaped charges will carry much more powder, typically 7.5 grams. Utilizing the same test standard, they will provide an entrance hole diameter of 0.29" and about 10.30" penetration. The charges (normally run in 2" guns) can be conveyed in a thin-walled carrier that will pass through 1.781" restrictions. A typical carrier OD might be 1.750". While such a large perforating gun assembly can be conducted down the tubing string, it is difficult to retrieve because of swelling, and possibly even splitting, the thin-walled gun. The size (after swelling) is so large as to prevent retrieval through a typical 23/8" completion string with the necessary installed apparatus. It is desirable to drop the perforating gun assembly after operation so that retrieval of the support equipment can be accomplished without sticking the portion of the equipment which swells after operation. It has been proposed to use frangible screws or other fasteners which hold the perforating gun assembly together. Ideally, one can size a frangible screw or pin which would timely shear. This requires balancing in that it must be sufficiently weak to shear in a wide range of circumstances and yet it must be strong enough to avoid shearing when the tool is run down the tubing string to the desired depth in the well. An example of such a structure is shown in U.S. Pat. No. 4,496,009 which utilizes an unfocused charge to assure that the shear screws or pins are broken. This has the drawback of requiring the use of a second kind of shaped charge in addition to those used for perforating. Furthermore, the unfocused shaped charges must be located as far as possible remote from the casing to prevent unintended casing damage on detonation. Such clearance is typically not available in limited clearance situations. It is therefore better to avoid frangible pins or screws and thereby avoid use of the unfocused charges. The present apparatus enables disconnection of the perforating gun assembly to drop a portion thereof to enable retrieval of the remaining portion of the equipment. This apparatus utilizes a plug positioned selectively in a set of locked collet fingers. The plug operates as a piston. When the perforating guns are fired, the piston is then driven upwardly, the shift thereof releasing the collet fingers so that the entire assembly breaks into two parts. The device is further constructed so that outgassing of the shaped charges does not pose a problem during running into the well even in the presence of elevated temperatures. This apparatus is summarized as a perforating gun assembly adapted to be run in a small ID, the assembly including a firing head at the upper end supporting a detent housing. A pressure responsive piston is deployed therein and has an upstanding stem, the stem collaborating with a set of spring operated plungers which lock the piston in an elevated position after firing. When the assembly is run into the hole, the piston is moved to the down position where it locks a set of collet fingers. The collet fingers join with a collet body which in turn supports the remainder of the perforating gun assembly therebelow. It includes a carrier with one or more shaped charges therein. Upon detonation, the piston is forced upwardly and locked in the elevated position after movement. When it moves, it releases a set of collet fingers and thereby enables the collet body to pull free. It drops away by gun blast and gravity and carries the carrier with it. It should be noted at this stage that the carrier is expanded or possibly split as a result of swelling at the locations where the shaped charges explode in the carrier. DRAWINGS So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. FIG. 1 shows the perforating gun for running into a tubing string, which perforating gun is armed with shaped charges; and FIG. 2 shows the perforating gun of FIG. 1 after shifting to release the lower portions of the perforating gun assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Attention is first directed to FIG. 1 of the drawings where the apparatus 10 will be described proceeding from the top of the sectional view. The structure includes a firing head 11 which is constructed to be joined with a rope socket and other running apparatus to enable the wireline operated device to be lowered in a tubing string. It is supported on a wireline which includes a signal conductor to provide the necessary signal for firing the shaped charges. The firing head is held in position by suitable allen head bolts 12 which joint to a detent housing 13. It is a hollow structure extending below the firing head which seals to the firing head at a set of seal rings 14. The firing head is operatively connected to a firing wire 15 deployed along the tool. The detent housing 13 is axially hollow. It has an internal shoulder which serves as a lock for a stop ring 16. It locks against the firing head assembly which is on the interior of the detent housing 13. The stop ring 16 is constructed with an axial passage to serve as a guide for a lock pin 17. The lock pin extends upwardly into the passage and is able to telescope into the passage. Further, the pin 17 is notched with a circular undercut at 18 to provide a locking groove. The locking groove is able to receive a plunger 19 which is forced into the groove by a spring 20. The spring 20 is located in the stop ring behind the plunger to force the plunger against the lock pin 17. The lock pin 17 is attached at the upper end of a movable piston 22. The piston 22 has an enlarged shoulder 23 thereabout to limit travel downwardly. The piston 22 is able to move upwardly. When it moves upwardly, it forces the pin 17 upwardly into a location where locking occurs. The piston 22 is also drilled axially with a passage to enable the firing wire 15 to extend through the piston. Sufficient clearance is provided to enable movement without binding or pulling on the firing wire. The detent housing 13 extends downwardly to terminate at a lower lip 24. The lower lip 24 abuts against a cooperative shoulder on a collet body 25. The body 25 is constructed with a set of collet fingers 26 extending upwardly therefrom. The fingers 26 are sized to fit around the edge of the piston 22. In other words, the piston 22 telescopes into the collet fingers. The collet fingers are made with suitable lengthwise finger splits. The collet fingers are also constructed with an enlargement 27 around the exterior of the piston. The enlargement is locked against a restraining detent 28. The detent 28 is an internal circular shoulder of sloping construction which conforms to the enlargement. In the arrangement of FIG. 1, the piston forces the enlargement 27 radially outwardly against the restraining detent 28 to assure locking. In this arrangement and so long as the piston is in the down position, it is impossible to pull the collet body downwardly because it is locked in the described manner. The collet body is axially hollow, terminating in a slot 30 cut across the collet body. The slot 30 supports a charge carrier 31, a mounting strip of a sacrificial nature, and supports one or more shaped charges 32. The shaped charges are mounted on the strip 31 at spaced locations, typically mounted thereon by positioning the shaped charges in drilled holes in the strip. The upper end of the strip is positioned in the slot 30 for alignment purposes. The collet body is constructed at the upper end with a set of seal rings 34. The seal rings 34 provide pressure sealing to the detent housing 13. The collet body 25 is rotationally aligned to the detent housing at the lower shoulder 24. As shown in FIG. 2 of the drawings, there is a notch 36 formed in the detent housing to receive an alignment bolt 37. This assures proper angular rotation and positions the two components as they are joined together. Moreover, the collet body 25 is fastened to the carrier housing by bolts 38 which are isolated by suitable seal rings 39 therebelow. The rings 39 seal against the interior of an elongate, hollow, cylindrical carrier 40. This carrier encases the several shaped charges. The carrier 40 terminates at a bull plug 42 which closes the bottom end of the carrier 40 and is sealed thereagainst by suitable seal rings 43. The plug is held in position by bolts 44. It also supports the lower end of the charge holder 31 which is received in a axial hole and cooperative slot identified at 45. This arrangement assures that the several shaped charges are held at a desired angular orientation. The firing wire 15 extends the length of the apparatus to connect to a detonator 46. That in turn connects with a detonating cord 47 which extends along the carrier housing. As will be understood, the several shaped charges are all connected for firing so that they form jet blasts in the intended fashion which perforate through the carrier 40 and out through the surrounding carrier and into the producing formation. Operation of the Present Apparatus Contrast FIG. 1 with FIG. 2 which shows the tool after firing. This is achieved by running the tool down a tubing string on the appropriately connected wireline until the tool is at a depth in the well opposite formations of interest. The tool is positioned at the required position to perforate through and into the formations of interest. At the proper time, a suitable electrical charge is provided, thereby assuring firing of the several shaped charges 32. When the tool is being run into the downhole location, there is a possibility that the explosives in the shaped charges will emit gases which will build up pressure; that is, the carrier 40 may build up internal pressure as a result of explosive outgassing. This risk is increased if the shaped charges are run into a hot well. In any case, the pressure in the carrier may build up. This pressure however, does not move the piston. There is a pressure relief flow path (48) through the piston which equalizes pressure on both sides of the piston. Thus, a slow or gradual build-up of pressure does not cause the piston to move. In the event the device operates in the intended fashion by detonation of the shaped charges, there is an instantaneous pressure build-up in the carrier 40. This rapid pressure build-up acts against the piston, forcing it upwardly. It slams upwardly against the lock ring. The groove 18 in the lock pin 17 receives the spring operated plungers which lock the piston 22 in the up position. The piston is held in the up position from this point in time, and is no longer available to lock against the collet fingers. The collet fingers are able to flex inwardly. This then releases the collet finger enlargements from the surrounding conforming shoulder. They deflect inwardly and slide over the streamlined shoulder 28, being pulled downwardly by gun blast and the weight of the structure therebelow. When the plug is in the up position of FIG. 2, the sole connection which holds the lower portions of the tool to the upper portions of the tool 10 is through the collet fingers. They deflect radially inwardly and release. When they release, they then flex inwardly, dropping the lower portion of the tool. Separation is achieved at the collet fingers. This drops the lower portion of the tool downhole and below the perforations. Typically, there is always room below the perforations to receive the lower portion of this spent apparatus. It will be noticed in FIG. 2 that the carrier is perforated by operation of the shaped charges. This dimpling effect forms protrusions which extend outwardly, expanding the diameter of the apparatus and thereby preventing retrieval in tight clearance tubing strings. (Sometimes the carriers even split). The apparatus which remains connected to the wireline does not expand. It can therefore be retrieved upwardly through the tubing string just as it was inserted through the tubing string. This retrieval is easily accomplished in the ordinary fashion. The portion of equipment which is retrieved is thus shown in the top portions of FIG. 2. This portion of equipment is then used to reassemble the firing gun assembly 10 for subsequent use. The portion which is dropped away, including the fired shaped charges, is disposable apparatus and is replaced by a new set of equipment for subsequent downhole runs. While the foregoing is directed to the preferred embodiment, the scope is determined by the claims which follow.

A perforating gun assembly is set forth in the present disclosure. It incorporates an upper elongate body having a firing head. The body supports a lower carrier which encloses one or more shaped charges which are positioned for forming perforations into a formation of interest. The sole means by which the carrier is attached to the body utilizes an upwardly extending set of parallel collet fingers having enlargements on the end. The collet fingers are locked in position against a conforming shoulder. Locking is achieved by a pressure movable piston. The piston is forced by detonation gases from the shaped charges away from the locked position, and the collet fingers are then permitted to flex, pulling free of the conforming shoulder to enable the carrier to drop from the elongate body.

You are an expert at summarizing long articles. Proceed to summarize the following text: REFERENCE TO RELATED APPLICATIONS This application is a continuation of, and claims priority to, U.S. application Ser. No. 10/352,086, filed Jan. 28, 2003 now U.S. Pat. No. 7,574,831, and entitled “RISER PAN COMPONENT FOR ON-SITE WASTE SYSTEMS,” which is a regularly-filed application entitled to the benefit of the filing date of U.S. Provisional Application No. 60/353,620, filed Feb. 1, 2002. The entire specifications of both applications are hereby explicitly incorporated herein by reference. BACKGROUND 1. Field of the Invention This disclosure relates generally to access covers for septic tanks and generally vertical access passageways between a septic tank (or another underground on-site waste disposal system or drainage collection system component) and grade level, and more specifically, to a component for use with (or without) a passageway formed by multiple stackable riser members, which component is capable of being cast into a concrete septic tank top, as well as being stackable with one or more riser members, and removably accepting a concrete or other heavy material cover or inspection lid therein, as well as being adapted to removably accept another cover thereon. 2. Description of the Prior Art An important consideration in the construction of septic tanks and other underground waste or drainage systems is how to provide water tight access to the buried system components for purposes of periodic maintenance (such as for pumping out a septic tank, which is typically done at least every few years, and in some cases, annually or even more frequently). Often, septic tanks and other underground liquid waste-holding components are provided with precast concrete covers, preferably with lift handles cast therein, in order to gain access to the interior of the septic tank. The concrete cover is typically located in the concrete top section, or lid, of the septic tank. There have been problems related to the use of make-shift access passage assemblies, such as modified chimney flues made of clay tile or cement, or extended lengths of large diameter pipe (such as smooth-walled PVC pipe, or corrugated or co-extruded pipe), used to form passageways between septic tanks and grade level. In order to overcome problems associated with such make-shift assemblies, a favorable alternative has been developed in the form of durable stackable riser members, as typified by the riser members disclosed in U.S. Pat. Nos. 5,617,679 and 5,852,901, owned by Tuf-Tite, Inc., the assignee of the present invention. Such riser members are typically made of comparatively lightweight, but sturdy material, such as polyethelene. Such injection-molded stackable risers allow for easy adjustment of the overall height of the access passageway, since additional risers can be easily added to increase the height, or risers can be removed to shorten the passageway. In a preferred manner of using these stackable riser members in conjunction with concrete septic tanks, the lowermost riser member is cast directly into the concrete top of the septic tank form. In this manner, perpendicularity of the entire access passageway, formed by a stack of risers, to the top of the septic tank is reliably established and maintained. As disclosed in U.S. Pat. No. 5,852,901, the riser members can be interconnected by means of a generally inverted U-shaped connecting member or channel provided at a lower end of the riser member, which is adapted to receive a free upper end of a next-lower riser member in a given stack of risers. It is recognized that later-developed riser members, such as the stackable riser sold by Polylok, Inc. and United Concrete Products, Inc. of Yalesville, Conn., employ variations of technique of interconnection of the riser members disclosed in U.S. Pat. No. 5,852,901. For example, as described in U.S. Pat. No. 6,484,451, the risers employ a channel end and an opposite tapered or straight end. The channel end of the riser member includes a middle wall, with notches or slots at regular intervals therein, defining two concentric channels. In a cylindrical stackable riser of the type disclosed in that patent, the middle wall is essentially an interrupted ring. The outermost channel receives the tapered or straight end of the next-lower stackable riser member, and the inner channel of the channel end, together with the notches in the middle wall of the channel end, receive vertical reinforcing ribs provided on the interior wall of the next-lower stackable riser member. Access passageways formed by stackable risers, such as those described in U.S. Pat. No. 5,852,901 of Tuf-Tite, Inc., are known to be used in conjunction with an injection molded cover used at grade level. The injection molded cover can terminate a stack of risers by being placed on the uppermost riser in the same manner of interconnection as the other risers, e.g. by an inverted U-shaped channel extending downwardly from the cover. The cover is secured to the uppermost riser by, for example, securement screws and screws which extend vertically through the cover at its perimeter, and which are received in screw bosses provided around the exterior of the uppermost riser in a stack of risers, all for safety and security reasons. Such covers are preferably provided with additional horizontally-oriented securement screws, screws, or other fasteners, which extend in a direction perpendicular to the vertically-extending securement screws. Instead of being received in screw bosses, these lateral securement screws may abut the upper lip of the uppermost riser which is received in a channel provided in the bottom of the cover, or alternatively, extend through screw holes provided in the upper lip of the uppermost riser in a stack of risers. Even with such securement methods available for the injection-molded covers, there exists a need for an additional cover in the form of a heavy-duty concrete (or other heavy material) secondary cover provided either just below the injection molded cover, i.e. at or near grade level, or alternatively, in or immediately adjacent to the concrete lid of the septic tank, i.e. at or near the bottom of the passageway. Those of ordinary skill in the art will understand that the term “concrete lid” of the septic tank refers to the large, horizontally-oriented concrete slab, typically on the order of 4 feet by 8 feet, for example, provided at the top of the septic tank having a capacity from about 750 to about 1,250 gallons, and supported by the walls of the septic tank, as opposed to the term “concrete cover”, which as used herein, refers to the well-known removable, generally smaller (and typically round) cover member associated with an opening in the concrete lid and used to gain access to the interior of the septic tank. Such concrete covers are generally flat, have cylindrically-shaped outer peripheral walls, while others may be tapered, and may include a stepped portion. The concrete covers sit atop the concrete lid, over the lid's access opening. These concrete covers allow a point of access to the interior of the septic tanks for drainage, cleaning, or other maintenance, including access to effluent filters provided at the inlet or outlet of the septic tank, for cleaning or replacement of the filters. Even in instances where a covered access passageway is provided over the concrete lid of the septic tank, there is a growing need for such secondary concrete or other heavy material covers over the lid's access opening in order to comply with many existing and imminent state and local regulations requiring such covers, as well as for added safety considerations. In those localities where there are no regulations requiring covers of a particular material or weight, it is still beneficial to use an internal cover within a septic tank or other on-site waste system access passageway, even if the cover is made of a lightweight material, such as plastic. It is recognized that conventional on-site waste system access passageways formed of extended lengths of PVC pipe have been outfitted with plastic or fiberglass covers, often secured to the top of the PVC pipe by screws. However, such arrangements are considered even less secure than the stackable risers with injection-molded covers. Further, the PVC pipe passageways, which typically have smooth inner walls, do not provide any means for accepting and retaining secondary concrete or other heavy material septic tank covers, either at or near grade level, or lower down in the passageway. One difficulty relating to the use of concrete covers in the lid of the septic tank, especially in combination with such passageways formed by stackable risers, occurs when the concrete cover is cast in place in the concrete lid of the septic tank. Such covers are typically formed in a steel forming pan used repeatedly by a concrete pre-caster, for the sole purpose of casting concrete covers. The installer has little room in which to cast the lowermost riser in place around the pre-cast concrete cover. Due to such space considerations, the casting of a concrete lid for a septic tank with a cast-in lowermost riser is often achieved using several separate pouring operations. First, a lowermost riser is placed on the floor and a steel pan is placed therein. Next, concrete is poured in the space between the outside of the steel pan and the inside of the lowermost riser. After that, concrete is introduced into the inside of the steel pan to form the concrete cover. The steel pan is often frustro-conical in shape, with a lower end having a smaller diameter than the upper end. Before the concrete cover dries, it is desirable to add a cast-in handle, such as the H1 “Cast In Handle” available from the present assignee, Tuf-Tite, Inc., i.e. to the center of the concrete cover to facilitate removal and replacement of the cover. Finally, concrete can be poured to form the concrete lid of the septic tank around the outside of the lowermost riser, thereby encasing and retaining the lowermost riser within that concrete lid. The concrete cover is removed from the ring of concrete formed in the interior of the lowermost cast-in-place riser, and the steel pan is removed for re-use. Due to the frustro-conical shape of the pan, once the steel pan is removed, the resulting concrete cover has a frustro-conical profile which can then be placed over the complementary concrete ring formed in the interior of the lowermost stackable riser, which serves as a mating angled seat for the concrete cover. There is a tendency for there to be a mis-matched fit, which results in a locking wedge fit between the concrete cover and the complementary concrete ring, which is undesirable. At least one such stackable riser, such as is available from Tuf-Tite, Inc., includes an interiorly-extending annular ring, which provides some internal support for the concrete interior ring. However, due to the relatively narrow width of the concrete ring within the concrete riser, there is some concern about degradation of the concrete seat for the concrete cover. Over the years, repeated access to the septic tank via the concrete cover may tend to cause chips or cracks in the concrete seat, particularly if people accessing the tank drop the concrete cover in place from any significant height above the top of the septic tank, as is not uncommon due to both the weight of the concrete cover and the depth of some septic tanks. It would be desirable if the lowermost, cast-in-place riser could also form the mold pan for the concrete cover and also remain in place as the seat for the concrete cover when the concrete septic tank lid is installed underground on a septic tank. This approach would advantageously avoid the need for a separate steel form pan, reduce the number of pouring operations during casting, and add reliability to the resulting seat for the concrete cover. The manner in which these and other benefits of the present invention are achieved will be explained in greater detail in the following Detailed Description of the Invention and the drawings. DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a riser pan of a first embodiment of the present invention; FIG. 2 is a perspective, partially exploded view of the riser pan shown in FIG. 1 , in combination with a pair of stackable risers and a cover for use at grade level; FIG. 3 is a front elevation view of the riser pan shown in FIG. 1 ; FIG. 4 is a bottom perspective view of the riser pan shown in FIG. 1 ; FIG. 5 is a bottom plan view of the riser pan shown in FIG. 1 ; FIG. 6 is a cross-sectional view of the riser pan shown in FIG. 1 , taken along lines 6 - 6 of FIG. 1 ; FIG. 7 is an environmental cross-sectional view of the riser pan, stackable riser, and cover combination shown in FIG. 2 , with the riser pan cast into a concrete lid of a septic tank, and showing a cross section of a concrete cover received in the riser pan; FIG. 8 is a perspective environmental view, partially broken away and exploded, of a riser pan of the type shown in FIG. 1 , cast-in-place into a concrete lid of a septic tank, and positioned over the outlet port of the septic tank, and without any additional riser components, but with an injection-molded cover for the riser pan, a concrete cover to be received in the riser pan, and a sealing gasket to be received between a flat portion of the concrete cover and a flat portion of the riser pan to form a substantially liquid-tight seal between the concrete cover and the riser pan; FIG. 9 is an enlarged cross-sectional view, broken away, taken along circular line 9 in FIG. 6 , of the riser pan of FIGS. 1-8 ; FIG. 10 is a perspective, partially exploded view of a riser pan of the type shown in FIG. 1 , in combination with a pair of stackable risers and a cover for use at grade level, depicting placement of the riser pan in an alternate position (i.e. higher in a stack of risers than is shown in FIG. 2 ); FIG. 11 is a perspective view, partially broken away, of a second embodiment of the riser pan, wherein the riser pan is formed as an integral part of a stackable riser member; FIG. 12 is a cross-sectional view of the second embodiment riser pan of FIG. 11 , taken along lines 12 - 12 of FIG. 11 , with cross-sections of a portion of the two conventional risers immediately above and below the riser pan shown in phantom lines for better viewing; FIG. 13 is a bottom perspective view of the alternate riser pan shown in FIG. 11 ; FIG. 14 is an exploded perspective view of the alternate riser pan shown in FIG. 11 in combination with an injection-molded cover for the riser pan; FIG. 15 is an exploded perspective view of a third embodiment of the riser pan in combination with another form of existing prior art stackable riser member, and additionally showing in phantom lines alternate, more preferred positions for the exterior annular ledge of the riser pan and for the stackable riser; FIG. 16 is a perspective view of the alternate riser pan and prior art stackable riser combination shown in FIG. 15 , and also showing in phantom lines alternate, more preferred positions for the exterior annular ledge of the riser pan and for the stackable riser; FIG. 17 is an exploded perspective view of the alternate riser pan and prior art stackable riser combination shown in FIG. 15 , with the relative positions of the riser pan and stackable riser reversed, depicting this third embodiment of the riser pan stacked above the prior art stackable riser; FIG. 18 is a cross-sectional view, broken away, of the alternate riser pan and stackable riser combination shown in FIG. 17 ; FIG. 19 is a cross-sectional view, broken away, of the alternate riser pan and stackable riser combination shown in FIGS. 15 and 16 ; FIG. 20 is a perspective view of a fourth embodiment of the riser pan, as integrally formed with the alternate type of riser member shown in FIG. 15 ; FIG. 21 is a cross-sectional view, broken away, of the alternate riser pan and riser integral combination as shown in FIG. 20 ; FIG. 22 is a perspective view of a riser pan of a fifth embodiment of the present invention; FIG. 23 is a cross-sectional view of the riser pan shown in FIG. 22 , taken along lines 23 - 23 of FIG. 22 ; FIG. 24 is an enlarged cross-sectional view, broken away, taken along circular line 24 in FIG. 23 of the riser pan of FIGS. 22 and 23 ; FIG. 25 is a perspective view of a riser pan of a sixth embodiment of the present invention; FIG. 26 is a cross-sectional view of the riser pan shown in FIG. 25 , taken along lines 26 - 26 of FIG. 25 ; FIG. 27 is an enlarged cross-sectional view, broken away, taken along circular line 27 in FIG. 26 of the riser pan of FIGS. 25 and 26 ; FIG. 28 is a perspective view of a riser pan of a seventh embodiment of the present invention; FIG. 29 is a cross-sectional view of the riser pan shown in FIG. 28 , taken along lines 29 - 29 of FIG. 28 ; and FIG. 30 is an enlarged cross-sectional view, broken away, taken along circular line 30 in FIG. 29 of the riser pan of FIGS. 28 and 29 , and showing a cross-section of a sealing gasket provided on the interior of the riser pan. DETAILED DESCRIPTION OF THE INVENTION A first embodiment of a riser pan 10 for use in conjunction with an access passageway formed of stackable, interconnecting risers 12 , 14 is shown in FIGS. 1-10 . In a preferred embodiment, the riser pan 10 takes the form of an injection-molded cylindrical member made of high density polyethylene. More specifically, the riser pan 10 includes an upper cylindrical wall 16 , a lower pan portion 18 , and an intermediate, generally flat annular ring 20 . The pan portion 18 is preferably frustro-conical, has a lowermost edge 22 and an upper end 24 . The frustro-conical pan portion 18 is tapered inwardly, such that its diameter at the lowermost edge 22 is less than at the upper end 24 . In a preferred embodiment of the riser pan 10 , the degree of taper of the pan portion 18 is in the range of between approximately 0° and 45°, and preferably about 14.796° for a 24″ riser pan, but those of ordinary skill in the art will appreciate that an even wider range of angles for the taper are possible, and even varying angles within the length of the taper so as to impart a curvilinearly-profiled surface to the frustro-conical pan portion 18 , and all are within the scope of the present invention. While the incline of the frustro-conical pan portion 18 preferably extends substantially the entire height of the pan portion 18 , alternatively, and also within the scope of the present invention, the pan portion 18 could include both generally vertical and generally inclined portions so as to form a stepped profile within the pan portion 18 . In the event a stepped profile is employed, it is further recognized that the degree of incline of the inclined portions may differ from one another to facilitate removal of a cover cast within the riser pan, among other benefits. Preferably, as best seen in FIGS. 1 and 9 , the riser pan 10 is provided with a standing circular rib 15 having a generally vertical outer surface 17 and an inner surface 19 that is preferably slightly tapered or inclined. Inasmuch as the standing circular rib 15 allows a concrete or other material cover to have a stepped profile, as discussed below, the degree of taper of the pan portion 18 may be 0° without causing the cover to fall through pan portion 18 . The degree of incline of the inner surface 19 of the standing circular rib 15 is preferably in a range of about 0° (i.e., vertical) to about 5° from vertical with respect to the generally flat annular ring 20 of the riser pan 10 . However, it is recognized that other degrees of incline for inner surface 19 are possible. The preferred subtle incline to the inner surface 19 of the standing circular rib 15 advantageously facilitates proper centering and alignment of a concrete or other heavy material cover 58 (see FIG. 7 ; discussed in more detail below). It is recognized that while the internal cover 58 disclosed herein is described as being made of concrete or other heavy material, it is also within the scope of the present invention to use an internal cover made of a lightweight material, such as injection molded plastic. The portion of the generally flat annular ring 20 between the upper end 24 of the frustro-conical pan portion 18 and the standing circular rib 15 provides a circular, generally flat, step 21 . In those applications in which a cover 58 is taller than the frustro-conical pan portion 18 , i.e. where the cover 58 extends further up into the region of the riser pan 10 defined by the standing circular rib 15 , the step 21 advantageously provides a generally flat interface between the cover 58 and the riser pan 10 . Inasmuch as obtaining a water-tight seal is significantly more difficult between inclined, as opposed to flat, surfaces, it is preferable that any means for providing or enhancing a water-tight seal between the riser pan 10 and the cover 58 be accomplished in the area of the step 21 . For example, an O-ring or generally flat annular sealing ring gasket 61 may be provided on the step 21 to form a substantially water-tight seal between the riser pan 10 and a cover 58 received therein. By way of example only, the inner side 19 of the standing circular rib 15 may be horizontally spaced anywhere from ¼-inch from the upper end 24 of the frustro-conical pan portion 18 to a location ¼-inch inwardly from the outer wall, and the standing circular rib 15 may have a height of ½-inch to 1 inch, preferably ¾-inch, but may be made taller or shorter, if desired, by the manufacturer. The standing circular rib 15 may also be spaced closer to or farther from the upper end 24 of the frustro-conical pan portion 18 , if desired by the manufacturer. The generally flat annular ring 20 preferably extends radially outwardly from the upper end 24 of the frustro-conical pan portion 18 past a lower end 26 of the upper cylindrical wall 16 , and terminates at an outer edge 28 which is outside the upper cylindrical wall 16 . Thus, an annular ledge 30 is provided around the exterior of the lower edge 26 of the upper cylindrical wall 16 , which, in this first embodiment, co-extends with the surface provided inside the upper cylindrical wall 16 by the generally flat annular ring 20 . The upper cylindrical wall 16 terminates at an upper end 25 . The annular ledge 30 provides a useful gripping portion for use during installation of the riser pan 10 when placed onto a passageway 31 of stackable risers 12 , 14 (see FIG. 2 ) at a location other than its most preferred cast-in location at the concrete lid section of the septic tank. Also, while being buried in the ground as part of such a passageway 31 formed, at least in part, by stackable risers 12 , 14 and the riser pan 10 , the backfill (not shown) rests upon the annular ledge 30 to help hold the riser pan 10 in its position relative to the stackable risers 12 , 14 , thereby improving the lateral stability of the entire passageway 31 . Furthermore, the backfill also tends to exert downward loads on the annular ledge 30 , which tends to push the riser pan 10 down toward other stackable risers (not shown in FIG. 2 ) that are interconnected in the passageway beneath the riser pan 10 . As discussed in U.S. Pat. No. 5,852,901, which is incorporated herein by reference, the stackable risers 12 , 14 are provided with horizontal, outwardly-extending annular ledges 29 , which provide a similar function. As seen in FIGS. 2 and 10 , the stackable risers 12 , 14 may each include a plurality of such outwardly-extending annular ledges 29 , as the ledges 29 advantageously improve rigidity of the risers 12 , 14 , and thereby increase the rigidity of the entire passageway 31 . This first embodiment of the riser pan 10 further includes a plurality of exterior, vertically-oriented ribs 32 extending above the annular ledge 30 along the outside of the upper cylindrical wall 16 , which are provided to help distribute load transmitted to the riser pan 10 from a next-higher riser 12 stacked thereon. In addition to the ribs 32 , several screw bosses 33 , each having sidewalls 34 , 36 , an inner wall defined by an outer portion of the upper cylindrical wall 16 , and an outer wall 37 , are provided at periodic locations about the upper cylindrical wall 16 , which also extend above the annular ledge 30 . These screw bosses 33 may take the form of a pair of closely-spaced ribs which are adapted to securely receive a threaded screw therebetween, but it is preferred that the screw bosses 33 be enclosed on the bottom and sides thereof, so as to prevent dirt or, more importantly, concrete (when the riser pan 10 is cast into a concrete septic tank lid), from entering the screw bosses 33 and obstructing the screw-receiving opening therein. Preferably, the screw bosses 33 may be hollow cylindrical or, in the embodiment shown, substantially rectangular hollow polygonal members. The purpose of such screw bosses 33 is to enable securement of an injection molded polyethelene riser cover 38 directly to the top of the riser pan 10 or riser 12 , 14 , if it is desired to place a riser pan 10 at or near grade level, i.e. at the top of a passageway 31 , as shown in FIG. 10 . The screw bosses 33 need not be internally threaded to faciltitate securely receiving a threaded screw therein, inasmuch as the opening within the screw bosses 33 is sized so as to become self-threading, i.e. the threads of the securement screws will cut into the interior walls of the screw bosses 33 upon initial securement of the molded cover 38 thereon. Additional screw bosses 35 are also preferably provided, which are spaced apart from the screw bosses 33 . These additional screw bosses 35 extend downwardly from the annular ledge 30 . Like the screw bosses 33 , these additional screw bosses 35 are preferably enclosed, aside from the screw-receiving bore therein, to prevent dirt or concrete from interfering with or corroding a screw (not shown) received in the additional screw boss 35 . Because the additional screw bosses 35 are spaced from the screw bosses 33 , it will be recognized that screw bosses 33 will also be out of alignment with screw bosses 33 r of an adjacent riser 12 to which the riser pan 10 is secured, as shown in FIG. 10 . Instead, the screw received in the additional screw boss 35 is received in the screw boss 33 r aligned with the additional screw boss 35 . It is recognized that there are often instances where a septic tank may be buried such that its concrete lid is just below grade level. As shown in FIG. 8 , the riser pan 10 advantageously facilitates the use of two covers, one being the injection-molded cover 38 secured to the top of the upper cylindrical wall 16 of the riser pan 10 , and the other being a cover 58 (shown in FIG. 7 ) made of concrete (or some other heavy material) fitting within the frustro-conical pan portion 18 , in such applications where there is essentially no room for the use of access passageways such as those formed by the use of multiple interconnected stackable risers 12 , 14 . When the cover 58 is made of concrete, which is typically the case, such a concrete cover 58 may advantageously be cast directly in the riser pan 10 , thereby avoiding the need for a separate mold for casting the concrete cover 58 . It is recognized that there are applications in which the concrete or other heavy material cover 58 is adequate, and no external injection molded cover need be used. As best shown in FIGS. 4 , 6 and 9 , the underside of the riser pan 10 includes a channel 40 , generally of an inverted U-shape in cross-section, which extends downwardly from the generally flat annular ring 20 and ledge 30 . The channel 40 has legs or sidewalls 42 , 44 , which extend generally about the entire periphery of the riser pan 10 . As described in more detail in certain other embodiments discussed below, it is recognized that these legs or sidewalls 42 , 44 , while preferably continuous to provide optimum water tightness, could be interrupted legs or sidewalls without departing from the scope of the present invention. The channel 40 may be advantageously sized to receive an uppermost male edge 46 of a complementary riser 14 , in applications where it is desired to stack the riser pan 10 higher in a passageway 31 , rather than the riser pan 10 being cast, as at a lower level, into the concrete septic tank lid 56 . It is recognized that the sidewalls 42 , 44 of the channel 40 may alternatively be spaced apart any desired distance by the manufacturer, so as to accommodate more conventional access passageway components, such as corrugated pipe or smooth-walled PVC pipe of a given diameter. Thus, the riser pan 10 of the present invention can be used to cap off existing access passageways or flutes with both an injection-molded, securely screwed riser cover 38 , and also accommodate a secondary concrete cover just below grade level, as may be highly desirable to increase the safety of existing septic tank installations. It can be used as well to bring (i.e., retrofit) such existing in-ground waste systems into compliance with newer state and/or local regulations requiring multiple covers to septic tank access openings. Another application wherein the riser pan 10 may be used to retrofit an existing access passageway is a passageway 31 formed by a plurality of stackable risers. A homeowner desiring to install a secondary cover would simply remove the uppermost riser 14 of the existing access passageway and replace it with a riser pan 10 . The riser pan 10 would accommodate both a concrete or other heavy material cover 58 in its frustro-conical pan portion 18 , as well as a securely-screwed injection molded outer primary cover 38 on its upper cylindrical wall 16 . Yet another potential application for the riser pan 10 is in an access passageway formed entirely of cylindrical concrete segments. Advantageously, one could cast the riser pan 10 such that it is sandwiched between two cylindrical segments within the passageway, i.e. two risers 12 , 14 , thus providing a means, by way of the frustro-conical pan portion 18 of the riser pan 10 , to use a secondary concrete or other heavy material cover 58 at a desired height within the access passageway. Most preferably, the sidewalls 42 , 44 of the inverted, U-shaped channel 40 are of equal length, i.e. height, to one another. It is found that, when casting the riser pan 10 into the concrete form of the septic tank lid, concrete can flow horizontally when riser pan 10 sits on top of the concrete lid form for the septic tank. This allows the concrete to fill any voids under the inverted, U-shaped channel 40 . Alternatively, if the sidewalls 42 , 44 were of different heights, for example if the inner sidewall 42 were taller than the outer sidewall 44 , the concrete would have difficulty flowing around the inner sidewall 42 , and there would most likely be undesirable voids left between the riser pan 10 and the concrete lid of the septic tank. Also, with a taller internal sidewall 42 , there is less even distribution of vertical loads coming down through the passageway 31 . FIG. 4 also shows the presence of additional ribs or gussets 48 , which are preferably provided at regular intervals, in this first embodiment of the riser pan. These gussets 48 extend from the inner sidewall 42 of the channel 40 , along the underside of the generally flat annular ring 20 , and down along the outside of the frustro-conical pan portion 18 , terminating at the lowermost edge 22 of the frustro-conical pan portion 18 . The gussets 48 help maintain the rigidity of the frustro-conical pan portion 18 , and increase the stability of the frustro-conical pan portion 18 , which is advantageous inasmuch as the frustro-conical pan portion 18 is intended to support a secondary concrete or other heavy material septic tank cover 58 therein. It is recognized that the septic tank cover 58 may be made of a suitably strong material other than concrete, although concrete is desirable for its weight and is an approved material for use as a septic tank cover in many jurisdictions. In order to provide even additional stability to the frustro-conical pan portion 18 for the riser pan 10 , it will be appreciated by those of ordinary skill in the art that the gussets 48 , which appear in FIG. 4 to terminate at a flat edge 50 along the bottom of the generally flat annular ring 20 , actually extend above the generally flat annular ring 20 . Turning back to FIG. 1 , there can be seen a plurality of gusset extensions 52 , disposed in the embodiment shown in 45° intervals, which extend from the gussets 48 directly opposite each respective gusset extension 52 on the opposite side of the generally flat annular ring 20 . These gusset extensions 52 , which extend up the inside of the upper cylindrical wall 16 and terminate along the outside of the standing circular rib 15 , help distribute loads exerted on the frustro-conical portion to the upper cylindrical wall 16 . The gusset extensions 52 also reinforce the standing circular rib 15 ; the extensions 52 advantageously help resist damage to the standing circular rib 15 as a heavy cover 58 is repeatedly inserted in and removed from the riser pan 10 . The gusset extensions 52 may be further reinforced by the vertically oriented ribs 32 , some of which are directly opposite the upper cylindrical wall 16 from respective gusset extensions 52 . Advantageously, the gusset extensions 52 are preferably each provided with a flat top 53 (see FIGS. 6 and 7 ), which can accommodate, and thereby help support, an inner sidewall 54 of an inverted generally J-shaped channel extending downwardly from either a stackable riser 12 , 14 or a cover 38 . That is, the vertically oriented ribs 32 on the outside of the upper cylindrical wall 16 preferably terminate, in this first embodiment of the riser pan, an appropriate distance from the upper end 25 of the upper cylindrical wall 16 , so that the outer sidewall 55 of the J-shaped channel of either a stackable riser 12 , 14 or cover 38 rests thereon. (See FIG. 7 ) Thus, the flat top 53 of the gusset extensions 52 , the upper end 25 of the upper cylindrical wall 16 , and the tops of the vertically oriented ribs 32 all preferably cooperate to distribute vertical loads imparted to the riser pan 10 from stackable risers 12 , 14 and/or the molded riser cover 38 . The U-shaped channel 40 of the riser pan 10 also enables multiple riser pans 10 to be vertically nested together for storage, shipping, or retail display, and alternatively, to be nested with and between riser members 12 , 14 at any desired location within the stack. Advantageously, several riser pans 10 may be cast into a single concrete septic tank lid 56 at different locations therein. For example, one of the riser pans 10 (not shown in FIG. 8 ) can be cast into the concrete tank lid 56 such that it is positioned over the septic tank inlet, a second riser pan 10 can be cast into the concrete lid 56 over the outlet of the septic tank (as shown in FIG. 8 ), and, for optimal access and so as to facilitate pumping out the septic tank, a third riser pan 10 (also not shown in FIG. 8 ) could additionally be cast into the concrete lid 56 so that it is generally centrally positioned over the septic tank to provide interior access. Typically, the concrete lid 56 of a septic tank has a thickness in a range from about 2½ inches to about 4½ inches. It will be recognized that neither the overall height of the riser pan 10 , nor the height of the screw bosses 33 , need to constitute a limit on the thickness of the concrete lid 56 into which the riser pan 10 can be cast. In the event one desires to cast a riser pan 10 into a concrete septic tank lid 56 of greater thickness than the height of the screw bosses 33 , an appropriately-sized shim (not shown), made, for example, of wood or foam, can be placed beneath the riser pan 10 during casting so as to raise the riser pan 10 a desired distance, such that the top of the screw bosses 33 , if desired, can be kept level with, or higher than, the top of the concrete septic tank lid 56 . It will be recognized that in such an installation, the resulting concrete cover 58 would have the thickness of the frustro-conical section of the riser pan 10 , so the concrete cover 58 would not necessarily extend completely to the bottom of the concrete tank lid 56 . When casting the riser pan 10 into a concrete tank lid 56 , the tops of the screw bosses 33 are exposed, so that an injection-molded cover 38 can be securely screwed directly to the riser pan 10 , as would occur once the injection molded cover 38 shown in FIG. 8 is seated on the top of the cast-in-place riser pan 10 . This is particularly desirable in instances where, as discussed above, the concrete septic tank lid 56 is just below grade level, so that two covers 38 , 58 can be used with such a septic tank. However, even in instances where the septic tank is deeply buried, and there is an elongated access passageway 31 formed of multiple stackable risers 12 , 14 , it is still desirable to have the screw bosses 33 exposed, inasmuch as there may, for example, become a need to remove the passageway 31 , leaving the septic tank buried, and it would be desirable to cap-off the septic tank with both a concrete cover 58 and an injection-molded cover 38 prior to filling in the hole left by the removed components which formed the passageway 31 . It is also preferable to cast the concrete cover 58 so as to not only fill the frustro-conical pan portion 18 , but also to fill (at least partially, but preferably, completely) the slightly higher region of the riser pan 10 bounded by the inner surface 19 of the standing circular rib 15 . As shown in FIGS. 7 and 8 , the resulting concrete cover 58 has a double-tiered shape having an upper tier 57 that is complementary to the region of the riser pan 10 bounded by the inner surface 19 of the standing circular rib 15 (which, as indicated above, is at least slightly inclined) and the step 21 , and then a lower tier 59 that is complementary to the frustro-conical pan portion 18 . The essentially stepped, double-tiered shape of the concrete or other heavy material cover 58 advantageously assists in preventing the cover 58 , once removed from the riser pan 10 , from being crookedly placed back into the riser pan 10 , and from being taper-locked within the pan portion 18 . The incongruity between the relatively shallow slope of the peripheral edge of lower tier 59 of the cover 58 and the relatively steep slope of the inner surface 19 of the standing cylindrical rib 15 , together with gravitational forces, tend to direct the lower tier 59 of the concrete or other heavy material cover 58 into a proper alignment and position within the frustro-conical pan portion 18 , thereby repeatedly facilitating proper centering and positioning of the concrete or other heavy material cover 58 within the riser pan 10 . In instances where an O-ring or annular sealing gasket 61 is provided on the step 21 , the proper centering and positioning of the cover 58 within the riser pan 10 improves the integrity of the liquid-tight seal between the cover 58 and the riser pan 10 . Alternatively, a sealing tape, a sealing caulk bead, or other suitable sealing means may be used on the step 21 to achieve a substantially liquid-tight seal between the cover 58 and the riser pan 10 . The diameter of the passageway 31 , which would preferably be equal to the diameter of the upper cylindrical wall 16 , and the diameters of the openings at the lowermost edge 22 and upper end 24 of frustro-conical pan portion 18 of the riser lid 10 , are all determined by the manufacturer. For example, riser pans 10 may be made with outer diameters of 16 inches, 20 inches, and 24 inches (as these are diameters commonly used in existing cylindrical stackable risers), with corresponding diameters of the respective opening at the lowermost edge 22 of the frustro-conical pan portion 18 being in a range from approximately 12-13 inches, 16-17 inches, and 20-21 inches. The riser pan 10 may have an overall height of about 5 inches, or some other height as selected by the manufacturer, with the height of the upper cylindrical wall 20 being approximately 3 inches, and the height of the frustro-conical pan portion being approximately 2 inches (both given for 5 inch high riser pans, for example). The upper end 24 of the frustro-conical pan portion in this first embodiment of the riser pan is, for example, spaced 2½ inch from the lower end 26 of the upper cylindrical wall 16 . Each of the screw bosses 34 , 36 is spaced, in this first embodiment shown, for example, ½ inch from the upper end 25 of the cylindrical wall 16 , such that the height of the top of each of the screw bosses 33 is, for example, 4½ inches, as measured from the lowermost edge 22 of the frustro-conical pan portion 18 . Turning to FIGS. 11-14 , a second embodiment of the riser pan 110 is shown, with like features to those described above with respect to the first embodiment being identified in this embodiment with the same reference number, increased by 100. In the second embodiment, the riser pan 110 shares many of the attributes of a riser 12 , 14 , as shown in FIGS. 2 and 7 , but also includes a frustro-conical pan portion 118 . The riser pan 110 may include one or more horizontal, outwardly-extending annular ribs 129 . The ribs 129 advantageously improve rigidity of the riser pan 110 , and thereby cooperate with adjacently-stacked risers 112 , 114 , as shown in FIG. 12 , to increase the rigidity of an entire passageway 131 of a plurality of risers 112 , 114 and riser pan 110 . Like the annular ledge 29 of the riser pan 10 of the first embodiment, the annular ribs 129 provide a gripping portion to facilitate handling and installation, backfill rests upon the ribs 129 to hold the riser pan 110 in position, while tending to exert downward forces on the ribs 129 , which tend to push the riser pan 110 downwardly toward a next-lower riser 112 in a passageway 131 . The riser pan 110 may further include a plurality of external, vertically-oriented ribs 132 along the outside of an upper cylindrical wall 116 of the riser pan 110 . The vertically-oriented ribs 132 help distribute loads transmitted to the riser pan 110 from a next-higher riser 114 . In addition to the ribs 132 , several screw bosses 133 , each having sidewalls 134 , 136 , an inner wall defined by an outer portion of the upper cylindrical wall 116 , and an outer wall 137 , are provided at periodic locations about the upper cylindrical wall 116 . These screw bosses 133 may take the form of a pair of closely-spaced ribs which are adapted to securely receive a threaded screw therebetween. The screw bosses 133 include an enclosed portion at least near the top opening thereof, extending down to at least an uppermost of the horizontal ribs 129 , as best shown in FIG. 13 , so as to prevent dirt or, more importantly, concrete, from entering the screw bosses 133 and obstructing the screw-receiving opening therein. Preferably, the screw bosses 133 may be hollow cylindrical or, in the embodiment shown, substantially rectangular hollow polygonal members. The purpose of such screw bosses 133 is to enable securement of an injection molded polyethelene riser cover 138 directly to the top of another riser (not shown) or to the top of the riser pan 110 , if it is desired to place a riser pan 110 at or near grade level, i.e. at the top of a passageway 131 . The screw bosses 133 are sized such that the threads of the securement screw will cut into the interior walls of the screw bosses 133 upon initial securement of the molded cover 138 thereon, as shown in an exploded view in FIG. 14 . A third embodiment of the riser pan of the present invention is shown in FIGS. 15-19 . In the drawing figures depicting this third embodiment, like features to those described above with respect to the first embodiment are identified with the same reference number, increased by 200. The riser pan 210 of this third embodiment, as in the embodiments described above, includes a frustro-conical pan portion 218 to accommodate a concrete septic tank cover of the type shown in FIG. 7 as reference number 58 , and the riser pan 210 is adapted for use with existing prior art stackable risers 212 , 214 . The riser pan 210 has an upper cylindrical wall 216 and between the upper cylindrical wall 216 and the frustro-conical pan portion 218 is an intermediate, generally flat annular ring 220 . Instead of external, vertically-oriented ribs, in this third embodiment a plurality of vertically-oriented ribs 232 are provided on the inside of the upper cylindrical wall 216 . Unlike the gusset extensions 52 (which are shown in FIGS. 6 and 7 to each have a flat top 53 spaced downwardly from the upper end 25 of the upper cylindrical wall 16 , so as to support an inner sidewall 54 of an inverted J-shaped channel at the lower edge of a riser 12 ) and the vertically-oriented ribs 32 of the first embodiment (which terminate some predetermined distance below the upper end 25 of the upper cylindrical wall 16 , and support the outer sidewall 55 of the inverted J-shaped channel of the riser 12 ), the vertically-oriented ribs 232 extend to the upper end 225 of the upper cylindrical wall 216 in this third embodiment. The riser pan 210 includes an annular ledge 230 which may co-extend with the surface provided inside the upper cylindrical wall 216 by the generally flat annular ring 220 , like in the first embodiment. However, because there are no external vertically-oriented ribs, in order to strengthen the riser pan 210 it is recognized that it may be preferable to provide the annular ledge at a higher point along the upper cylindrical wall 216 , as shown in phantom lines in FIG. 15 and designated by the reference number 230 a. The prior art riser 212 which the riser pan 210 is adapted to receive is provided with an inverted channel with an inner sidewall 254 , an outer sidewall 255 , and intermediate the inner and outer sidewalls 254 , 255 is an interrupted annular ring 260 . The annular ring 260 is interrupted by a plurality of rib-receiving notches or gaps 262 , spaced to coincide with the vertically-oriented ribs 232 . The vertically-oriented ribs 232 are received in the rib-receiving notches or gaps 262 , thereby interlocking the interrupted annular ring 260 with the vertically-oriented ribs 232 and preventing rotation of the riser pan 210 relative to the riser 212 . Like the annular ledge 230 , it is recognized that the riser 212 may be provided with an external riser ledge 264 . Furthermore, as the riser 212 used in conjunction with the riser pan of this embodiment lacks external vertical ribs, it may be preferable to locate the external riser ledge 264 in a position near the upper end of the riser 212 , such as shown in phantom lines in FIGS. 15 , 16 as reference number 264 a. Turning to FIG. 17 , the underside of the riser pan 210 includes a plurality of gussets 248 extending between the frustro-conical pan portion 218 and an underside of the intermediate, generally flat annular ring 220 . The gussets 248 terminate at an interrupted annular ring 266 . The annular ring 266 is interrupted by a plurality of rib-receiving notches or gaps 268 , spaced to coincide with vertically-oriented ribs 270 located on the inside cylindrical wall of a riser 214 . An annular wall 272 may also extend downwardly from the annular ledge 230 , spaced outwardly of the interrupted annular ring 266 , forming a channel between the interrupted annular ring 266 and the annular wall 272 to receive an upper edge 274 of the sidewall 276 of the prior art stackable riser 214 . As seen in FIGS. 18 , 19 the upper edge 274 of the sidewall 276 of the risers 212 , 214 may be stepped inwardly, i.e. having a reduced thickness as compared to the rest of the sidewall 276 , so that the annular wall 272 forms a continuous wall with the sidewall 276 of the risers 212 , 214 when stacked to form a vertical conduit or passageway. This will enhance the transfer of vertical loads downwardly through the stack. A fourth embodiment of the riser pan is shown in FIGS. 20 and 21 . Like features to those described above with respect to the first embodiment are identified with the same reference number, increased by 300. The riser pan 310 is essentially a hybrid of the second and third embodiments described above. Like the riser pan 110 of the second embodiment, the integral combination riser and riser pan 310 of this fourth embodiment preferably has a cylindrical sidewall 316 of a height similar to the height of a regular riser, but also includes a frustro-conical portion 318 to accommodate a secondary cover like the concrete cover 58 shown in FIG. 7 . Like the riser pan 210 of the third embodiment, the riser pan 310 has at the lower end of the cylindrical sidewall 316 an interrupted annular ring 366 , which is interrupted by a plurality of rib-receiving notches or gaps 368 . An annular wall 372 may be provided axially outwardly of the interrupted annular ring 366 , preferably as an integral extension of the sidewall 316 . An inner sidewall 354 of an inverted channel is also provided axially inwardly of the interrupted annular ring 366 . The riser pan 310 further includes a plurality of vertically-oriented ribs 332 , which in this embodiment are located on the interior of the cylindrical sidewall 316 of the riser pan 310 . For purposes of nesting the riser pan 310 with other similar riser pans for shipping or storage, the rib-receiving notches or gaps 368 are sized to accommodate the vertically-oriented ribs 332 of a next-lower riser pan. Likewise, the vertical ribs 270 of a riser 214 , such as on the riser shown in FIG. 17 , fit within the rib-receiving gaps 368 . Thus, the interrupted annular ring 366 at the lower end of the wall 316 of the riser pan 310 can lockingly receive either a riser 214 or another riser pan 310 . The riser pan 310 also has gussets 348 extending between the exterior of the frustro-conical portion 318 and the inner sidewall 354 . The flat edge 350 at the top of each of the gussets 348 rests along an intermediate, generally flat annular ring 320 running between the frustro-conical portion 318 and the inner sidewall 354 . In yet another, i.e. fifth embodiment, shown in FIGS. 22-24 , the riser pan 400 may be similar in most respects to the first embodiment described above, but omits the standing circular rib. Instead, the generally flat annular ring 420 extends from the upper end 424 of the frustro-conical pan portion 418 , through the upper cylindrical sidewall 416 , and terminates at an outer edge 428 , outside the upper cylindrical sidewall 416 , thus forming an annular ledge 430 on the exterior of the upper cylindrical sidewall 416 . Contrary to the gusset extensions 52 described above with respect to the first embodiment, the gusset extensions 452 of this embodiment do not terminate along an outer surface of a standing circular rib, because there is no such standing circular rib. Instead, each of the gusset extensions 452 has an angled surface that extends from a flat top 453 of the gusset extension 452 to the generally flat annular ring 420 . In all other respects, the riser pan 410 of this embodiment is substantially identical to the riser pan 10 disclosed in the first embodiment, so further description of the present embodiment is omitted as unnecessarily duplicative. In a sixth embodiment of the riser pan 510 , shown in FIGS. 25-27 , instead of a standing circular rib 15 extending upwardly from the annular ring 20 , as in the first embodiment of the riser pan 10 , a downwardly-depending circular rib 515 extends from the lowermost end 522 of the frustro-conical pan portion 518 . The downwardly-depending circular rib 515 preferably has two parallel vertical surfaces 517 , 519 , as opposed to a vertical outer surface 17 and inclined inner surface 19 . However, it is recognized that the inner surface 519 may be inclined, if desired by the manufacturer, to facilitate casting of a cover within the riser pan 510 . The riser pan 510 includes gussets 552 and a generally flat annular ring 520 as in the fifth embodiment riser pan 410 , described above, as well as other aspects shown in the drawing figures and described above with respect to previous embodiments, but not described in detail with respect to this embodiment for the sake of avoiding unnecessary repetition. Like the standing circular rib 15 shown and described in the first embodiment riser pan 10 , the downwardly-depending circular rib 515 of this sixth embodiment facilitates casting in place of a relatively thicker concrete cover (not shown). Inasmuch as many septic tank lids may have a thickness greater than the height of the frustro-conical pan portion 518 , the circular rib 515 effectively increases the height available in which to cast a concrete cover without the concrete spilling over into the interior region of the riser pan 510 bounded by the upper cylindrical sidewall 516 . The resulting concrete cover would have a two-tiered shape, with a lowermost generally cylindrical portion coinciding with the region of the interior of the riser pan 510 bounded by the downwardly-depending circular rib 515 , and an upper conical portion coinciding with the region of the interior of the riser pan 510 bounded by the frustro-conical pan portion 518 . Turning to FIGS. 28-30 , a seventh embodiment riser pan 610 utilizes both a standing circular rib 615 a , as in the first embodiment, and a downwardly-depending circular rib 615 b , as in the sixth embodiment. The standing circular rib 615 a preferably has a vertical outer surface 617 a and an inclined inner surface 619 a , similar to the surfaces 17 and 19 in the first embodiment described above. As in the sixth embodiment, the downwardly-depending circular rib 615 b preferably has parallel outer and inner surfaces 617 b , 619 b , but it is recognized that the inner surface 619 b may be inclined, if desired by the manufacturer, to facilitate casting of a cover within the riser pan 610 . By providing the standing circular rib 615 a , the riser pan 610 advantageously assists in preventing the cover, once removed from the riser pan 610 , from being crookedly placed back into the riser pan 610 , like in the first embodiment. As opposed to a two-tiered profile complimenting an inclined pan portion, a step, and an inclined standing circular rib, however, a cover cast into the riser pan 610 would have a profile complimenting not only those portions of the riser pan 610 , but also complimenting the inner surface 619 b of the downwardly-depending rib 615 b . An O-ring or annular sealing gasket 661 may also be provided on the step portion 621 intermediate the standing circular rib 615 a and the pan portion 618 to facilitate a liquid-tight sealing engagement between the riser pan 610 and an internal cover received therein. It will be recognized that variations to the foregoing description of the preferred embodiment may be made without departing from the present invention, and which would still be within the scope of the appended claims. For example, the riser pan may have a square or other polygonal shape, rather than round, and the frustro-conical pan portion may have the same or a different shape than the outer wall of the riser pan, as may be desirable for use with stackable risers or other passageways having shapes other than cylindrical.

An integrally formed riser pan member for use as a modular component within an access passageway for an on-site waste disposal system, such as a septic tank, to receivably retain a secondary cover member within, the riser pan member including a cylindrical body having an upper portion having a vertical wall member adapted to receive another modular passageway component thereon, and a lower portion which includes an integral pan portion to seatably receive a secondary cover member. The riser pan member further includes an annular ring between the upper and lower portions. The riser pan member can be employed as a lowermost, a highermost, or as an intermediate component in, for example, an access passageway formed of multiple stackable riser members. In addition, the riser pan member may be formed integrally with a stackable riser member.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a device for fairways with changing salt concentrations or suspended sediment concentrations in brackish water areas as a result of tidal flows, with a lateral branch or enlargement in the manner of a lock entrance or a harbor basin, to prevent deposits of silt/sand, whereby in the vicinity of the beginning of the branch or enlarged portion, with respect to an incoming flood current, by means of a current deflection wall that is located at some distance from the bank, a channel is realized, the cross section area of which equals a small portion of the inlet cross section area of the branch or enlargement, and the inlet opening of which lies in the fairway in the vicinity of the beginning, and the outlet opening of which lies in the vicinity of the branch or enlargement. In other words, and according to at least one embodiment of the present invention, this invention relates to an arrangement for minimizing the deposit of silt and/or sand in brackish fairways characterized by changing salt concentrations and/or suspended sediment concentrations resulting from tidal flows and having a lateral branch or enlargement, such as a lock entrance or a harbor basin, whereby a current deflection wall is placed offshore in the vicinity and downstream of the entrance to the lateral branch or enlargement so that a channel is formed having an inlet opening lying in the fairway in the vicinity of and downstream of the entrance to the lateral branch or enlargement and an outlet opening lying in the vicinity of the branch or enlargement, the cross sectional area of the channel equaling a small portion of the cross sectional area of the entrance to the branch or enlargement. 2. Background of the Invention On lateral branches or enlargements of this type, one problem is that for the major part of the flood tide, the salt concentration or suspended solids contents in the watercourse is greater than in the body of water of the lateral branch or enlargement, and thus a density current originates from the fairway to the branch or expansion, which is active primarily close to the bottom and thereby carries large amounts of silt or sand along with it which, it is well known, can result in large deposits of sediment. As a result of the sediment deposits formed, there are high maintenance costs for dredging and deposition of the dredged material. The density of a tidal fairway can vary both as a function of changes in the salt concentration as well as changes in the suspended sediment concentration. Salt concentrations can change because, during flood tide, the highly salty sea water can penetrate farther into a tidal flow, and during ebb tide, can be kept farther out to sea. The suspended sediment concentration changes during flood and ebb tide as a result of the varying location of the turbidity zone, or by the increase and decrease of the turbulent tidal currents. All these effects are caused by the tide. Because increases in the salt content and also in the suspended sediment concentration in the fairway can be achieved a great deal more rapidly than in lateral branches or expansions, the density differences described above occur over the total length of time involved in a tide, with the result that density currents are realized, by which large amounts of sand or silt are deposited in the lateral branches. German Patent No. 37 07 074 C1 describes a system of the prior art to prevent circulation currents in fairways by installing current deflection walls at harbor entrances, thereby reducing the resulting lenticular sedimentary deposits. These realizations, however, cannot be used to solve the problems described above, because the object of such a system is merely to reduce the eddy currents caused by the tidal flow. Attempts have also been made to prevent density by means of a air bubble curtain or underwater skirts suspended on buoys, thereby preventing the ingress of silt and sand. Both methods have been found to be unsatisfactory. OBJECT OF THE INVENTION The object of the present invention, according to at least one embodiment, is to develop an arrangement and a method for diverting tidal flows in brackish fairways that substantially solves the problems encountered in systems of the known art. SUMMARY OF THE INVENTION The invention teaches that the baffle partition is located in the upper portion with reference to the water depth and an additional deflection wall is located in the lower portion of the water depth in the watercourse. This additional deflection sill diverts a near-bed density current of the fairway toward the middle of the fairway, starts at the bank in the vicinity of the current deflection wall and projects into the fairway. In other words, and according to at least one embodiment of the present invention, the invention teaches that a current deflection wall is located in the fairway at an upper level and an additional deflection sill is located at a lower level, the upper and lower levels having reference to the water depth. The additional deflection sill, which starts at the bank in the vicinity of the current deflection wall and projects into the fairway in the direction of the incoming flow, diverts a near-bed density current of the fairway toward the center of the fairway and away from the lateral branch or enlargement. As a result, a simple deflection and filling current control system is created, whereby a near-bed density current in the lower portion of the watercourse at the beginning of the branch or enlargement is diverted by the deflection sill toward the watercourse, In the upper portion of the water area, a channel is formed in the form of a filling current control system with the bank, by means of which the quantities of water at the flood tide to fill the branch or enlargement and create a counter current for an incoming density current, and thus prevents the entry of silt and sand that is carried along near-bed into the lateral branch or enlargement. In other words, and according to at least one embodiment of the present invention, as a result, a simple deflection and filing current control system is created, whereby a near-bed density current in the lower portion of the fairway at the beginning of the branch or enlargement is diverted by the deflection sill toward the center of the fairway while the channel at the upper level of the watercourse foams a filling current control system so that quantities of water with the incoming flood tide to fill the branch or enlargement creating a counter current to the incoming density current with the result that the silt and sand normally carried along near-bed is prevented from entry into the lateral branch or enlargement. In one advantageous embodiment, in particular to control the ebb current, the invention teaches that in the vicinity of the end of the branch or enlargement opposite the area of the current deflection wall, starting from the bank in the fairway, a deflection sill that extends toward the middle of the fairway is located at least in the lower portion with regard to the water depth. In other words, and according to at least one embodiment of the present invention, in one advantageous embodiment, to control in particular an ebb current, the invention teaches that a deflection sill projecting from a bank of the fairway toward the center of the fairway is located offshore in the vicinity and upstream of the entrance to the lateral branch or enlargement and opposite the site of the current deflection wall. Such a sill is located at least in the lower level with regard to the water depth. To prevent the formation of turbulence behind the deflection sills, the invention teaches that an area between the deflection wall and bank is backfilled with material. For this purpose, in a refinement of a realization that has favorable flow conditions, one outer edge of the area of the deflection sill filled with material is rounded The invention also teaches that the current deflection wall is located on columns, at least in the area outside the area filled with material. In one preferred embodiment, each deflection sill is realized in an S-shape to divert the flow without creating turbulence. The invention further teaches that the areas of the current deflection wall and the deflection sill partially overlap. The invention further teaches that the point of the bank that lies in the vicinity of the end of the branch or enlargement opposite the current deflection wall is cut off in the downstream direction. In other words, and according to at least one embodiment of the present invention, the invention additionally teaches that the point of the bank in the vicinity of and upstream of the entrance to the branch or enlargement opposite the baffle partition is cut off in the downstream direction. The above discussed embodiments of the present invention will be described further hereinbelow with reference to the accompanying figures. When the word “invention” is used in this specification, the word “invention” includes “inventions”, that is, the plural of “invention”. By stating “invention”, the Applicants do not in any way admit that the present application does not include more than one patentably and non-obviously distinct invention, and maintains that this application may include more than one patentably and non-obviously distinct invention. The Applicants hereby assert that the disclosure of this application may include more than one invention, and, in the event that there is more than one invention, that these inventions may be patentable and non-obvious one with respect to the other. BRIEF DESCRIPTION OF THE DRAWINGS The invention is explained in greater detail below with reference to the exemplary embodiments illustrated in the accompanying drawings, in which: FIG. 1 is a schematic diagram of a device in action during flood tide; FIG. 2 is a schematic diagram of a device in action during ebb tide with deflection sills on both sides of a branch; FIG. 3 shows a realization like the one illustrated in FIG. 1 as a detail with backfilling and a rounded edge of the bank as well as a rounded edge of the backfilled area; FIG. 4 is a sectional drawing along Line IV—IV in FIG. 3, on an enlarged scale; FIG. 5 is a sectional drawing along Line V—V in FIG. 3, on an enlarged scale, with a partly elevated filling current control system and rounded edge on the end of the backfilled area behind the deflection system; and FIG. 6 shows a realization of a lateral enlargement with a streamlined shape of the bank point and a backfilled area on the ebb-side end of the branch. DESCRIPTION OF THE PREFERRED EMBODIMENT In the illustrated systems, there is a river 1 as the fairway, from which a harbor basin 2 branches off. The river 1 , when there is flood tide, has the tidal current 4 , and also, as a result of the incoming seawater, a near-bed density current 3 . At ebb tide, the arrows show the ebb current 19 and the near-bed density current 18 . The arrows also show the density equalization currents at the flood tide (Arrows 17 ) and ebb tide (Arrows 22 , which are active whenever the salt or suspended sediment concentration in the fairway 1 is greater than in harbor basin 2 . In other words, and according to at least one embodiment of the present invention, in the illustrated systems of FIGS. 1 and 2, river 1 is shown as the fairway from which a harbor basin 2 branches off. When there is flood tide, river 1 has the tidal current 4 , and also, as a result of the incoming seawater or turbidity zone, a density current 3 near the bottom. At ebb tide, the illustrated arrows represent the ebb current 19 and the density current 18 flowing in the downstream direction The arrows 17 and 22 also show the density equalization currents during flood tide and ebb tide, respectively, which are active whenever the salt or suspended sediment concentration in fairway 1 is greater than in harbor basin 2 . In the vicinity of the beginning 20 of the branch 2 , there is a filling current control system with a current deflection wall 6 in the upper portion, and a deflection sill 5 in the lower portion. With the bank 23 , with the current deflection wall 6 , a channel 24 is formed in the upper portion of the water depth. As a result of channel 24 with the inlet opening 8 in the river area 1 and the outlet opening 9 in the transitional area between the fairway 1 and the harbor basin 2 , at flood tide, a quantity of water is guided in the current direction 7 . This quantity of water is split into the tidal filling volume 11 for the harbor basin 2 and a return flow portion 10 which flows back into the fairway 1 , and displaces a density equalization current 17 back into the fairway 1 . In the area 20 , a deflection sill 5 is also located in the lower portion of the water depth behind which, up to the bank 23 , a space 13 is backfilled up to an approximately vertical closing wall 26 with material, e.g. with sand or rocks. During flood tide, the S-shaped deflection sill 5 that begins at the bank 23 and extends in the fairway 1 in the vicinity of the beginning 20 of the branch 2 displaces the density current 3 close to the bottom as shown by the arrows 12 away from the harbor entrance 2 . The density current 12 that is diverted in this manner, in connection with the partial outflow 10 , causes a density equalization current 17 during flood tide to be displaced so far from the harbor entrance 2 that it remains in the fairway 1 . As a result of this displacement, the deposits of sand and silt that would otherwise be carried along by the density equalization current in the vicinity of the bottom of the fairway, and the resulting high sedimentation in the harbor basin 2 , can be prevented. At the end of he branch 2 , beginning at the bank 25 , there is a deflection sill 14 which is located in the lower portion of the water depth, and extends in an S-shaped curve into the fairway 1 . The area 15 between the deflection wall 14 and the bank 25 , like the area 13 , is backfilled with material up to the vertical closing wall 16 . The purpose of the deflection sill 14 , during ebb tide, with the tidal current 19 and the density current 18 , is to deflect this density current 18 as shown by the arrows 27 , so that in combination with an outflow 28 from the harbor basin 2 , the penetration of a density equalization current 22 is prevented, and in this manner a deposit of silt or sand in the harbor basin 2 that would otherwise occur during ebb tide can be prevented. Steel, reinforced concrete or wood are suitable materials for the construction of the deflection systems. The closure wall 26 of the backfilled area 13 for the deflection sill 5 is realized in a streamlined rounded shape 29 . FIG. 6 illustrates a streamlined variant of a bank point 21 in connection with the deflection sill 14 and a streamlined closure wall 16 of a backfilled area 15 and a likewise =streamlined, cut-off bank point 21 ′, which work together at flood tide to improve the outflow of a partial current 10 . In the exemplary embodiment illustrated in FIG. 5, the current deflection wall 6 is located outside the backfilled area 13 of the deflection sill 5 on elevated pilings in the form of columns 30 . One feature of the invention resides broadly in the device for a fairway that has changing salt concentrations and/or suspended sediment concentrations in brackish water as a result of tidal flows, with a lateral branch or expansion in the manner of a lock entrance or a harbor basin, for the prevention of silt and/or sand deposits, whereby in the vicinity of the beginning of the branch of expansion, with respect to a flood tide current; by means of a current deflection wall that is located at some distance from the bank, a channel is formed, the cross sectional area of which represents a small portion of the inlet cross sectional area of the-branch or expansion, and the inlet opening of which lies in the fairway in the vicinity of the beginning and the outlet opening of which lies in the vicinity of the branch or expansion, characterized by the fact that the current deflection wall 6 is located in the upper area with respect to the water depth, and in the lower area with respect to the water depth in the fairway there is an additional deflection sill 5 , which diverts a near-bed density current toward the center of the river, runs outward from the bank 23 in the vicinity of,the current deflection wall 6 and projects into the fairway 1 . Another feature of the invention resides broadly in the device characterized by the fact that in the vicinity 21 of the end of the branch or enlargement 2 opposite the current deflection wall 6 , starting from the bank 25 in the fairway 1 there is a deflection sill 14 that extends toward the middle of the river, at least in the lower portion with respect to the water depth. Yet another feature of the invention resides broadly in the device characterized by the fact that an area 13 , 15 between the deflection wall 5 , 14 and the bank 23 , 25 is filled with material. Still another feature of the invention resides broadly in the device characterized by the fact that one edge 16 , 26 of the area 13 , 15 of the deflection sill 5 , 14 backfilled with material is rounded on top. A further feature of the invention resides broadly in the device characterized by the fact that the current deflection wall 6 is located on columns 30 at least in the vicinity outside the area 13 that is backfilled with material. Another feature of the invention resides broadly in the device characterized by the fact that each deflection sill 5 , 14 is realized in an S-shape to divert the current without forming turbulence. Yet another feature of the invention resides broadly in the device characterized by the fact that the areas of the current deflection wall 6 and the deflection sill 5 partly overlap . Still another feature of the invention resides broadly in the device characterized by the fact that the bank point 21 ′ that lies in the vicinity 22 of the end of the branch or expansion 2 opposite the current deflection wall 6 is cut off in the downstream direction. Some examples of rounded or streamlined structures in tidal streams and the may be found in the following U.S. Pat. Nos.: 4,330,224, 4,498,806, 4,665,578, 4,846,004, 4,881,848, 4,887,361, 4,923,335, 5,067,851, 5,165,357, 5,707,265 and 5,725,326. The components disclosed in the various publications, disclosed or incorporated by reference herein, may be used in the embodiments of the present invention, as well as, as equivalents thereof. The appended drawings in their entirety, including all dimensions, proportions and/or shapes in at least one embodiment of the invention, are accurate and to scale and are hereby included by reference into this specification. All, or substantially all, of the components and methods of the various embodiments may be used with at least one embodiment or all of the embodiments, if more than one embodiment is described herein. Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses, if any, are intended to cover the structure described herein as performing the recited function and not only structural equivalents but also equivalent structures. The invention as described hereinabove in the context of the preferred embodiments is not to be taken as limited to all of the provided details thereof, since modifications and variations thereof may be made without departing from the spirit and scope of the intention.

Arrangement for fairways in brackish water tidal zones to prevent or minimize deposits of silt and/or sand in a branch or enlargement of such fairways. The invention is realized by the installation of a flow wall system. At the entrance to the branch or expansion, a current deflection wall is submerged in the fairway at an upper level some distance from the bank so that a channel is formed near the entrance to the branch or enlargement to direct an flood tide into the branch or enlargement and a deflection sill is juxtaposed with the partition at a lower level to divert an incoming near-bed current of the fairway away from the entrance to the branch or enlargement. The cross sectional area of the channel is small when compared with the cross sectional area of the entrance to the branch or enlargement.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION [0001] The present invention relates to an arrangement for securing an implement to a carrier mounted to lifting arms, particularly those of a front loader boom, where the implement and carrier can be fastened to each other by movable latch rods that can be moved between latched and unlatched positions either manually or by a remotely controlled motor. BACKGROUND OF THE INVENTION [0002] A known type of latch arrangement for securing an implement to a carrier mounted to lifting arms of a boom comprises a rod arrangement mounted to the carrier for being shifted laterally between latched and unlatched positions, with the rod arrangement being spring biased to its latched position. The rod arrangement can be either manually or hydraulically moved to the unlatched position, where a secondary latch is engaged by partially rotating the rod by the action of a second spring. The rod arrangement can then be released with the rod arrangement remaining in an arrested unlatched position until an implement coupled to the carrier is rolled back so as to engage the latch rod arrangement causing it to rotate out of its arrested position thereby disengaging the secondary latch permitting the latch rod arrangement to be moved to its latched position by the biasing spring. Such a prior art securing arrangement is disclosed in U.S. Pat. No. 7,001,137. [0003] Another known type of latch arrangement includes a remotely operable latch rod arrangement which is biased toward a latched position and is selectively moveable to an unlocked position by an extensible and retractable hydraulic cylinder controlled by a solenoid operated valve which is controlled by a circuit including a latching control switch and a height control switch connected in series so that both must be closed to complete a circuit to the control valve so as to prevent unlatching if the height sensing switch senses a height above a preselected safe height for implement detachment. U.S. Pat. No. 7,467,918 discloses such a prior art latch rod control. [0004] One drawback associated with the patented designs is that a failure of the biasing mechanism when the implement is attached to the boom could result in the latch rod migrating to its unlatched position. Another drawback of the patented designs is that an operator may not be aware if the latching rod arrangement becomes jammed or the like resulting in a partially latched implement. Further, while hydraulic cylinders are effective devices for moving the latching rod arrangements to their unlatched positions, hydraulic fluid leakage is always a problem and the provision of hydraulic hoses and control valves often take up valuable space and require special design considerations resulting in increased cost. SUMMARY OF THE INVENTION [0005] According the present invention, there is provided an improved remotely operated latching system for detachably connecting an implement to a carrier mounted to a lifting arm. [0006] An object of the invention is to provide a remotely operated latching system which is compact and reliable. [0007] A more specific object of the invention is to provide latching system including a latch rod arrangement which is extendable from a latched position to an unlatched position, with a secondary latch arrangement being provided for rotating the latch rod arrangement into an arrested position once the latch rod arrangement in its extended, unlatched position, with an actuator for extending the latch rod arrangement acting to aid rotation of the latch rod arrangement into its arrested position. [0008] These and other objects are accomplished by using a linear electric motor for operating the latching rod arrangement, with a microprocessor based digital electronic control for the motor including safety interlocks for preventing unlatching of the implement if the boom is not in a lowered position. The electronic control unit also includes a capability to monitor operating conditions and to apprise the operator of the operating condition, through the means of an LEDs, where a slowly flashing light indicates that the latch rod arrangement is being extended to establish an unlocked condition, a quickly flashing light indicates a jammed condition and full extension being indicated by a steady light. The motor control includes an operating switch which may be placed in a manual over-ride mode whereby the operator may cycle the motor to extend and retract the latch rod arrangement such as to use the latching sections of the rod arrangement to “chip” through frozen material, or the like, blocking the passage of the latching sections to the latching position. [0009] These and other objects of the invention will be understood by a reading of the ensuing description together with the appended drawings BRIEF DESCRIPTION OF THE DRAWINGS [0010] FIG. 1 is a right side elevational view of a loader boom having a rear end mounted to a support frame and a front end coupled to an implement carrier to which an implement is attached. [0011] FIG. 2 is a right rear perspective view of an implement carrier equipped with a remotely controlled latching mechanism constructed in accordance with the principles of the present invention and showing the latch rod arrangement in a latched condition for securing an implement to the carrier. [0012] FIG. 3 is a right front perspective view of the implement carrier and latching mechanism shown in FIG. 2 . [0013] FIG. 4 is an enlarged left bottom perspective view of a right end region of the carrier of FIG. 2 showing the mount and shield assembly for the electric motor. [0014] FIG. 5 is a top view of the linear electric motor showing its connection to the right end region of the operating rod assembly of the latch rod arrangement FIG. 6 is a rear view of the carrier shown in FIG. 2 , but showing the operating rod in an unlatched position. [0015] FIG. 7 is a left end view of the carrier shown in FIG. 6 , but showing the lever arm in phantom so as to show the latch rod positioned in the upper region of the guide slot and the secondary latch rod positioned in a lower region of the guide slot. [0016] FIG. 8 is a view like FIG. 6 , but showing the latch rod arrangement in an unlatched, arrested position. [0017] FIG. 9 is a left end view of the carrier shown in FIG. 8 , but showing the lever arm in phantom so as to reveal the latch rod arrangement in a lower region of the guide slot and the secondary latch rod below the guide slot, and showing a lower region of the left loader boom arm in dashed lines together with carrier being shown in dashed lines in a rolled back condition wherein an upper surface of the boom arm is in contact with, and holds the latch rod arrangement in a non-arrested position in an upper region of the guide slot, with the secondary latch rod being positioned for re-entry into the guide slot. [0018] FIG. 10 is a perspective view of a left end region of the implement carrier shown in FIG. 6 , but showing an alternate embodiment featuring a coil spring which acts in compression to resist movement of the latch rod arrangement from its latched position while at the same time acting in torsion to bias the operating rod towards the bottom of the guide slot arrangement. [0019] FIG. 11 is schematic of the electrical circuit embodying the microprocessor and sensors used for controlling operation of the electric linear motor and giving an operator visual indication of whether or not the latch rod arrangement is operating correctly. DESCRIPTION OF THE PREFERRED EMBODIMENT [0020] Referring now to FIG. 1 , there is shown a front end loader 10 equipped with an attachment in the form of a bucket 14 . However, it is to be understood that the present invention may be used with other loaders and/or attachments. [0021] The loader includes a boom 28 comprising left and right, transversely spaced, fore-and-aft extending arms (only right arm 30 being shown) disposed for extending along opposite sides of a tractor (not shown) and each having a rear end pivotally attached, as by a pin 32 , to an upper region of a respective one of a pair of upright masts 34 , the masts 34 , in turn, being fixed to respective upper regions of a pair of upright mounting frames 36 located on opposite sides of, and having lower regions fixed to a frame (not shown) of the tractor. The boom 28 further includes a cross tube (not visible) having opposite ends projecting through, and joining the arms 30 together at a location forwardly of the tractor, with caps 38 being mounted on outer faces of the arms 30 so in closing relationship to opposite open ends of the cross tube. [0022] Mounted between a lower region of each of the masts 34 and the associated boom arm 30 is an extensible and retractable boom lift cylinder 40 having its rod end coupled to the mast 34 and its barrel end coupled to the arm 30 . An implement carrier 42 is pivotally attached, as at pins 44 to lower front end regions of each of the boom arms 30 , the carrier 42 , in turn, including an upper cross member 46 received within downwardly opening receptacles (not visible) of transversely spaced hooks 48 (only one shown) fixed to an upper region of the a backside of the bucket 14 . The bucket 14 is detachably coupled to a bracket arrangement (not shown) provided on the backside of the bucket 14 , as is described below in further detail. Provided for pivoting the carrier 40 about a horizontal axis defined by the pins 44 are a pair of extensible and retractable bucket tilt cylinders 50 (only one shown), each of which form one link of a leveling linkage 52 coupled, as at a pin 54 , between an upper end of each mast 34 and the implement carrier 42 , with extension of the cylinders 44 effecting clockwise rotation of the carrier 42 and associated bucket 14 about the horizontal axis defined by the pins 44 , while retraction of the cylinders 50 effects counterclockwise rotation of the carrier, and, hence, effects roll back of the associated bucket 14 , such roll back operation being important in the operation of latching the bucket 14 to, and detaching the bucket from, the carrier 42 , as is described below in further detail. [0023] Referring now to FIGS. 2 and 3 , it can be seen that the cross member 46 at the top of the carrier 42 has right and left end regions to which are attached right and left vertical plate assemblies. Specifically, the right vertical plate assembly includes a pair of transversely spaced outer and inner loader arm mounting plates 56 and 58 , respectively, having upper ends fixed to the right end region of the cross member 46 . Similarly, the left vertical plate assembly includes outer and inner loader arm mounting plates 60 and 62 , respectively, having upper ends fixed to the left end region of the cross member 46 . The right and left vertical plate assemblies 56 , 58 and 60 , 62 each have a fore-and-aft dimension that increases from top to bottom. While not required for carriers of smaller loaders, the carrier 42 further includes right and left, inner strengthening plates 64 and 66 also having upper ends joined to the cross member 46 and having lower ends that terminate forwardly of lower ends of the plates 56 - 62 . The bottoms of the plates 56 , 58 and the right inner plate 64 are joined together by a right rear cross bar 68 , while lower front regions of the plates 56 , 58 and 64 are joined together by a right front cross bar 70 . Extending between and fixed to the front and rear cross bars 68 and 70 at respective locations spaced outwardly from the inner plate 66 is an upwardly projecting locking bar receiving plate 72 . Similarly, the bottoms of the plates 60 , 62 and 66 are joined together by a left rear cross bar 74 having an inner end joined to a bottom rear location of the plate 66 , and being welded within complementary notches provided in the lower edges of the plates 60 , 62 , while a front cross bar 76 extends between and is joined to lower front regions of the plates 60 , 62 and 66 . Extending between and fixed to the left rear and front cross bars 74 and 76 , at locations spaced outwardly from the left inner plate 66 , is an upwardly projecting locking bar receiving plate 78 . [0024] A right tilt linkage mounting hole arrangement includes a pair of horizontal, axially aligned holes (only hole 80 in the plate 58 being visible) provided at an upper region in the right plate assembly comprising the plates 56 , 58 , while a left tilt linkage mounting hole arrangement includes a pair of horizontal, axially aligned holes (only hole 82 in plate 54 being visible) provided at a mid-height location of the plates 54 , 56 in axial alignment with the holes 74 . Respectively fixed to outer and inner faces of the plates 56 , 58 of the right plate assembly are a pair of short cylindrical tubes 84 that are arranged in axial alignment with the holes 70 . Likewise, a pair of short cylindrical tubes 86 are fixed to the inner and outer surfaces of the left plate assembly comprised by the inner and outer plates 54 and 56 so as to be in axial alignment with the holes 82 . Referring back to FIG. 1 , it can be seen that a pin 88 is received in each of the aligned pairs of holes 80 and 82 and serve to fix one end of a link of the bucket tilt linkage 52 to the right pair of arm mounting plates 56 , 58 of the carrier 42 . [0025] A right loader boom mounting hole arrangement includes a second pair of axially aligned holes (only hole 90 in plate 58 being visible) provided at lower rear locations of the plates 56 and 58 , and a left loader boom mounting hole arrangement includes a second pair of axially aligned holes (only hole 92 in plate 60 being visible) respectively provided at lower rear locations in the left pair of plates 60 and 62 . Fixed to outer and inner surfaces respectively of the right plate assembly, comprised of the pair of plates 56 and 58 , so as to be in axially alignment with each other and with the holes 90 are short cylindrical tubes 94 . Similarly, fixed to outer and inner surfaces respectively of the left plate assembly comprised of the pair of plates 60 , 62 so as to be in axial alignment with each other and with the holes 92 are short cylindrical tubes 96 . When the carrier 42 is mounted to the loader boom 28 , the right pair of boom arm mounting plates 56 , 58 and the left pair of boom arm mounting plates 60 , 62 respectively straddle lower front regions of the right and left boom arms 30 , with the holes 90 and 92 respectively receiving the pins 44 (see FIG. 1 ). [0026] Spaced below the pair of hooks 48 on the back side of the bucket 14 (see FIG. 1 ) are right and left, rearwardly projecting mounting lugs (not visible) respectively located for being received between the right strengthening plate 64 and the right latch rod receiving plate 72 , and between the left strengthening plate 66 and the left latch rod receiving plate 78 . Referring now also to FIG. 4 , it can be seen that a latch rod guide 100 is mounted to an inner surface of the right strengthening plate 64 , the guide 80 including a vertical portion 102 extending parallel to, and being spaced inwardly from the plate 64 , with the vertical portion containing a rod-receiving hole 104 disposed in horizontal axial alignment with rod-receiving holes 106 and 108 , respectively provided in the strengthening plate 64 and the rod-receiving plate 72 . On the left side of the carrier 42 , the loader arm mounting plates 60 , 62 , the latch rod-receiving plate 78 and the strengthening plate 66 respectively contain axially aligned holes 110 , 112 , 114 and 116 that are in axial alignment with the holes 84 - 88 and define a latch assembly pivot axis, these holes being brought into alignment with bores in the mounting lugs (not visible) of the bucket 14 for receiving latch rod elements, described below, to secure the bucket 14 to the carrier 42 . [0027] The present invention relates to a remotely operable latching mechanism 120 including an actuator arrangement 122 and a latch rod arrangement 124 . [0028] Referring now also to FIGS. 3 and 4 , it can be seen that the actuator arrangement 122 includes a motor mount and shield assembly 125 including a vertical motor mounting plate 126 tightly secured against a left face of the right strengthening plate 64 by a pair of bolt and nut assemblies 128 . As can best be seen in FIG. 4 , the support plate 126 is received within, and is shaped complementary to and is welded to, a right end region of an inverted channel-shaped motor shield 130 , which projects leftward from the strengthening plate 64 . Joined to, and projecting leftward from, a left face of the support plate 126 is a motor mounting clevis defined by upper and lower flanges 132 and 134 , which are disposed in parallel relationship to a top 136 of the shield 130 , the top 136 being inclined downwardly from front to rear. A bolt stem 137 of a motor mounting bolt and nut assembly 138 projects downwardly through the shield top 116 and through the aligned holes provided in the upper and lower flanges 132 and 134 so as to define an upright motor mount pivot axis having a purpose explained below. [0029] Referring also to FIG. 5 , it can be seen that a linear electric motor 140 comprises a sealed body 142 which is substantially rectangular in cross section. The electric motor 140 has a built in microprocessor (described in more detail below) which continuously monitors the performance of the motor and can be directly interfaced with programmable controllers. An example of a suitable electric motor are those included in the Electrak Pro Series marketed by Danaher Motion located in Radford, Va. Respectively located at front regions of right and left ends of the motor body 142 in approximate transverse alignment with each other are a mounting lug 144 , defined by a rod, and an extensible and retractable output shaft 146 . The mounting lug 144 contains an upright bore 148 in which the stem 137 of the bolt assembly 138 is received when the motor 140 is mounted beneath the top 136 of the motor shield 130 , as shown in FIG. 3 , the mounting lug 144 then being received between the motor mount flanges 132 and 134 . [0030] Referring back to FIGS. 2 and 3 , it can be seen that the latch rod arrangement 124 includes a horizontal, transverse operating rod assembly 150 including an intermediate coupling rod 152 having a right end loosely received within a left end of a tubular coupler 154 and connected thereto by a bolt and nut assembly 156 wherein the bolt stem is disposed crosswise relative to the motor mounting bolt stem 137 . The motor shaft 146 is loosely received in a right end of the coupler 154 and is connected thereto by a nut and bolt assembly 158 wherein the bolt stem is disposed parallel to the motor mounting bolt stem 137 . A left end region of the coupling rod 152 is tightly received within a right end region of an elongate tubular rod section 160 that is received in an opening 162 provided in the strengthening plate 66 , and in a guide slot arrangement comprising a pair of transversely aligned guide slots 164 respectively provided in the loader boom mounting plates 60 and 62 , with it being noted that slots similar to the slots 164 are provided in the plates 56 and 58 so that during manufacture the plates 56 and 58 are respectively interchangeable with the plates 60 and 62 . As can best be seen in FIG. 3 , the left end of the tubular rod section 160 is welded within an opening provided between opposite ends of a flat lever arm 166 disposed perpendicular to the rod section 160 . A rod is bent to form a handle 168 having an inner end of a horizontal transverse end section fixed to a rear end of the lever arm 166 , and having an outer end joined to a rearwardly extending hand grip portion. [0031] The latch rod arrangement 124 further includes right and left latch rods 170 and 172 . The right latch rod 170 includes a mounting portion 174 at its left end which is disposed along a lower front portion of the right end region of the tubular rod section 160 , with a pair of nut and bolt assemblies 176 including bolt stems extending through aligned bores provided in the coupling rod 152 and tubular rod section 160 so as to secure the rod 152 within the section 160 while solidly clamping the latch rod mounting portion 174 to the operating rod assembly 150 . Extending parallel to, and being axially offset to, the latch rod mounting portion 174 is a latch rod latching portion 178 , which is joined to the mounting portion by an intermediate portion 180 . [0032] As can best be seen in FIG. 3 , the left latch rod 172 includes a left end region which projects through a hole (not visible) provided in a forward end of the flat lever arm 166 and into a cylindrical tube 182 welded onto an outer surface of the arm 166 . A nut and bolt assembly 184 secures the latch rod 172 within the cylindrical tube 182 . [0033] When the latch rod arrangement 124 is in a latched position, as shown in FIGS. 2 and 3 , the latching portion 178 of the right latch rod 170 extends beneath the motor body 142 ( FIG. 3 ) and is received in the axially aligned holes 104 , 106 and 108 respectively provided in the rod guide bracket 100 , strengthening plate 64 and latch rod receptacle plate 72 . The left latch rod 172 is then received in the axially aligned holes 110 , 112 , 114 and 116 respectively provided in the left boom mounting plates 60 and 62 , the latch rod receiving plate 78 and the left strengthening plate 64 . [0034] Thus, the operating rod assembly 150 forms a leftward extension of the motor output shaft 146 and has a left end region projecting through the guide slot arrangement comprising the pair of transversely aligned guide slots 164 respectively provided in the left pair of plates 60 and 62 . The guide slots 164 are located approximately mid-way between the sets of holes 82 and 92 . As described above, the left latch rod 172 is fixed for movement with the operating rod 132 by the flat lever arm 166 . A secondary latch rod 186 has an outer end welded to a lower middle location of the lever arm 166 and, when the operating rod assembly 150 is in the latched position shown in FIGS. 2 and 3 , the secondary latch rod projects upwardly to the right through a lower region of the guide slot 164 provided in the outer left plate 60 , with the lever arm 166 then being disposed in a raised position flat against the left surface of the plate 60 . The handle 166 is provided for manual operation of the operating rod assembly 150 in the event of a failure of the electric motor 140 . [0035] Movement of the latch rod arrangement 124 from its latched position shown in FIGS. 2 and 3 to an extended unlatched position, shown in FIG. 6 , is resisted by a coil compression spring 188 received on the operating rod assembly 150 at a region just to the right of the inner boom arm mounting plate 62 and having opposite ends engaged with right and left flat washers 190 and 192 , respectively, with rightward movement of the washer 190 being prevented by a nut and bolt assembly 194 including a bolt stem projecting through the tubular rod section 160 , and with leftward movement of the washer 192 being prevented by the plate 62 . As can be seen in FIG. 6 , a coil tension spring 196 is coupled under tension with a hook at an upper end being engaged with a coil of the compression spring 188 and with a hook at a lower end being received within a hole provided in the strengthening plate 66 , the spring 196 acting to bias the tubular rod section 160 of the operating rod assembly 150 toward the bottom ends of the guide slots 164 for a reason described below. [0036] The secondary latch rod 186 is provided for retaining the operating rod assembly 150 in an arrested position, as shown in FIGS. 8 and 9 , wherein the operating rod assembly 150 has been shifted to the left a sufficient distance to withdraw the secondary latch rod 186 from the guide slot 164 , thereby permitting the action of the tension spring 196 to rotate the operating rod assembly 150 about the latch rod axis into a bottom region of the guide slots 164 , resulting in the end of the secondary latch rod 186 becoming misaligned relative to the adjacent guide slot 164 so as to retain the operating rod assembly 150 in its extended, unlatched position. As can be seen in FIGS. 7 and 8 , the extended motor output shaft 146 is misaligned relative to the axis of the operating rod assembly 150 which means that the motor housing 142 is rotated downwardly about the upright axis defined by the bolt and nut arrangement 138 , this downward rotation occurring gradually as the output shaft 146 extends with the result that the motor transfers a downward component of force to the operating rod assembly 150 that is added to that exerted by the tension spring 196 so as to aid in moving the operating tubular rod section 160 to the bottoms of the guide slots 164 . [0037] When the carrier 42 is rolled back, as shown in dashed lines in FIG. 9 , it can be seen that the tubular rod section 160 of the operating rod assembly 150 comes into contact with a forward surface 197 of the left loader arm 30 and lifts the rod section to the top region of the guide slot 164 , with the secondary latch rod 186 then being realigned with the guide slot 164 so as to permit the operating rod assembly 150 to be retracted to its latched position. [0038] Referring now to FIG. 10 , there is shown an alternate embodiment of the manner of effecting the latching of the secondary latch rod 186 . Specifically, the compression spring 188 of the first-described embodiment is replaced by a combined helically wound compression and torsion spring 188 ′, the latter having a straight left end section 198 that extends upwardly behind an abutment pin 200 that is fixed to, and projects to the right from, the plate 62 at a location adjacent an upper end of the adjacent guide slot 164 . A torsion adjustment nut 202 is secured to a right end of the spring 158 ′ and can be advanced toward the left along a threaded section (not shown) of the operating rod tube section 160 to cause an increase in the torsion pre-load of the spring 188 ′. Thus, the reaction of the force exerted by the spring end 198 on the abutment pin 200 is transferred through the spring to the tubular rod section 160 so as to urge the operating rod assembly 150 toward the bottoms of the guide slots 164 . Accordingly, the tension spring 196 used in the previously described embodiment is no longer needed. [0039] Starting with the implement carrier 42 mounted to the arms 30 of the loader boom 28 , an implement, such as the bucket 14 can be attached to the carrier 42 by positioning the carrier 42 so as to bring the cross member 46 into engagement with the downwardly opening receptacles of the mounting hooks 48 provided at the backside of the bucket 14 , and then by raising the bucket off the ground far enough that it pivots downwardly against the front of the carrier 42 . The transversely spaced pair of mounting lugs (not shown) at the backside of the bucket 14 will at this time be respectively in fore-and-aft alignment with the space between the right latch rod receiving plate 72 and the right strengthening plate 64 , and with the space between the left latch rod receiving plate 78 and the left strengthening plate 66 . The operator will then operate the bucket tilt cylinders 50 to cause the carrier 42 to roll back about its pivotal connections 44 of the carrier 42 with the boom arms 30 . This will cause the arrested operating rod assembly 150 to come into engagement with the front surface 197 of the left loader arm 30 and to be shifted towards the upper end region end of the guide slots 164 . At this point, the right end of the secondary latch rod 186 will come into register with the guide slot 164 in the plate 60 , while cross bores provided in the bucket mounting lugs will be in axial alignment with the holes respectively provided in the plates 64 , 72 straddling the right bucket lug, and provided in the plates 66 , 78 straddling the left bucket mounting lug. The motor 140 is then operated to cause it to retract thereby simultaneously moving the right latch rod portion 178 through the bore in the right bucket lug and then into the hole 108 provided in the latch rod receiving plate 72 , and moving the left latch rod 172 through the bore in the left bucket lug and then into the hole 116 provided in the left strengthening plate 66 . [0040] Referring now to FIG. 11 , there is shown a schematic of an electrical control system 210 for remotely controlling the operation of the linear electric motor 140 . Specifically, the electric control system 210 includes an electrical control unit (ECU) 212 connected to the motor 140 by a motor activation output signal line 214 . The ECU 212 preferably, but not necessarily, is a microprocessor which is embodied in the electric motor 140 and continuously monitors the performance of the motor. For purposes indicated below, the motor 140 embodies an electronic load sensor 216 and end of stroke limit switches 218 (extend limit) and 220 (retract limit) here depicted as being respectively connected to the ECU by conductors 222 , 194 and 196 . While not required, the end of stroke positions governed by the limit switches 218 and 220 could be programmable. [0041] A manually-operated control switch 228 for initiating activation of the motor 140 is located within the cab (not shown) of a tractor and is connected to the ECU 212 by a motor activation input line 230 . The control switch 228 may take various forms including: (1) a momentary “on” rocker switch, (2) a momentary “on” rocker switch with a 1 second delay, (3) a momentary “on” rocker switch with a ½ second delay and a ½ second release window trigger indicated by an LED, (4) a momentary “on” push button switch, (5) a momentary “on” push button switch with a recessed button, and (6) a momentary “on” push button switch with a recessed button with a ½ second delay and a ½ second release window trigger indicated by an LED. Also, instead of a single switch, two momentary toggle switches may be used, with each being toggled in opposite directions. A height sensor 232 , shown mounted on the right mast 34 in FIG. 2 , is connected to the ECU 182 by a height signal input line 234 and is provided for preventing actuation of the electric motor 140 when the carrier 42 is above a predetermined height off the ground. The boom height sensor 234 detects the pivot angle of the lifting boom 28 about the horizontal axis defined by the coupling pins 32 , which secure the boom arms 30 to the masts 34 . The height sensor 234 may be, for example, a potentiometer or an incremental angle transmitter which transmits this signal to the ECU 212 . Angular regions are stored in memory in the ECU 212 , in which an activation of the motor 140 can be prevented at inappropriate positions of the lifting boom 28 , for example, if it is raised beyond a height considered to be an upper height limit for safe disconnection of an implement from the carrier 42 mounted to the boom arms 30 . The angular regions, in which a signal sent by the height sensor 232 is to be ignored, can be permanently programmed or provided as input by the operator with an input key 236 provided in the tractor cab (not shown) and connected to the ECU by an input signal line 238 . The input key 236 can also be used to program the aforementioned travel end limits of the motor output shaft 146 . [0042] An LED indicator 240 is provided for apprising an operator of the operating condition of the motor 140 and boom 28 as determined by the load sensor 216 , output shaft end limit sensors 218 and 220 , and height sensor 232 . The LED indicator 240 is coupled to the ECU 212 by an output signal line 242 for receiving operation condition signals from the ECU 212 . [0043] Remote operation of the latching mechanism 120 through remote actuation of the linear electric motor 140 is described below with reference to FIGS. 1 , 2 and 11 . Assuming the implement 14 to be latched to the carrier 42 , as shown in FIG. 1 , and that the tractor 10 is properly located for depositing the implement 14 on the ground, operation to detach the implement 14 from the carrier is commenced by lowering the loader boom 28 so as to place the implement 14 close to the ground. The bucket tilt actuators 50 are then caused to retract to completely roll back the carrier 42 and associated implement, with the weight of the implement 14 thus being relieved from the latch rods 170 and 172 . The normally “off” switch 228 is then momentarily actuated to its “on” position so as to activate the motor 140 to cause extension of the motor shaft 146 and hence extension of the operating rod assembly 150 . Since the carrier 42 has been lowered, the height sensor 232 will not be activated and the signal sent by the switch 228 to the ECU 212 will result in an operating signal being sent to the motor 140 by way of the output line 214 . The motor 140 will then be activated to cause extension of the output shaft 146 and the operating rod assembly 150 . Assuming the latch rod 172 and the latch rod portion 178 are free to move so that no jamming occurs, extension of the latch rod assembly 150 will take place, causing the latch rod 170 and latch rod portion 178 to be fully pulled out of the associated left and right lugs (not shown) provided at the backside of the implement 14 . During extension of the motor output shaft 146 , the retract limit sensor 220 will initially be activated, then cease to be activated as the shaft moves away from its retract limit position, resulting in the LED indicator 212 receiving a signal causing it to blink slowly indicating continuous outward movement of the output shaft 146 . When the output shaft 146 reaches the extend limit position, limit sensor 218 will be activated, sending an input signal to the ECU 212 resulting in the LED indicator receiving a signal causing it to produce a steady light apprising the operator that the unlatch position has been achieved, with the secondary latch pin 186 then being withdrawn from the left guide slot 164 . The tension spring 196 , together with the motor 140 , which is now angled downwardly to the left, will then act to rotate the operating rod assembly 150 to the bottom end of the slots 164 , resulting in the secondary latch pin 186 becoming misaligned with the adjacent slot 164 so that the latch rod arrangement 124 is arrested in the unlatched position. The boom 28 can then be lowered to disengage the cross bar 46 from the hooks 48 at the backside of the implement 14 , thus permitting the tractor 10 to be backed away from the implement 14 . [0044] The implement 14 can once again be attached to the carrier 42 by a reverse operation. Specifically, the tractor 10 can be driven toward the backside of the implement 14 and the boom 28 and carrier 42 lowered so as to place the cross bar 46 beneath the downwardly opening hooks 48 . The boom 28 is then raised, with gravity causing the implement 14 to pivot downwardly about the axis of the cross bar 46 and rest against the carrier 42 , with left and right lugs at the backside of the implement 14 respectively being received between the right latch rod receiving plate 72 and right strengthening plate 64 , and between the left latch rod receiving plate 78 and the left strengthening plate 66 . To ensure axial alignment of the bores in the bucket lugs with the holes of the receiving plates 72 , 78 and the strengthening plates 64 , 66 , the tilt cylinders 50 are retracted to effect full roll back of the carrier 42 and associated implement 14 . Not only does this result in the desired bore and hole alignment mentioned above, but it also results in the tubular section 160 of the operating rod assembly 150 coming into engagement with the top surface of the left loader boom 30 and being lifted towards the top of the guide slots 164 , this lifting initially resulting in the right end of the secondary latch pin 186 entering the left guide slot 164 . The normally open, motor actuating switch 228 is then manually actuated to send a motor control signal to the ECU 212 . The ECU 212 will then send a motor activating signal causing the motor 140 , at one second intervals, to attempt to retract. If the motor 140 causes the right and left latch rods 170 and 172 to move more than 5 mm., then the motor retracts under full power and the LED indicator 232 blinks slowly. If either one or both of the latch rods 170 and 172 jam, then an overload condition is sensed by the overload sensor 216 which sends a jam signal to the ECU 212 resulting in an output signal being sent to the LED indicator 242 which causes the LED to blink rapidly, with power to the motor 140 via the line 214 being terminated, with the motor 140 going into a latch mode causing the output rod 160 to be retracted. If, instead of a jam occurring, the retract limit of the motor output shaft 146 is reached, the retract limit sensor 220 is activated resulting in the ECU 212 receiving a signal which is processed, the ECU 212 then terminating power to the LED indicator 240 , which shuts off, and with power simultaneously being cut to the motor 140 . [0045] If jamming happens during latching operation, the operator may use the input key 236 to send an override signal to the ECU 212 , which permits the motor control switch 228 to be intermittently switched “on” and “off” so that the motor 140 is intermittently energized so as to cause the output shaft 146 to extend and retract with the result that the latch rod portion 178 and latch rod 172 are moved back and forth so as to chip away at any material that may be causing an obstruction in the aligned holes provided on the carrier 42 and the lugs (not shown) at the backside of the implement 14 . Upon the material becoming dislodged, the input key 236 can be operated to send a signal to the ECU 212 for resumption of normal operation. [0046] Thus, it will be appreciated that the electric linear motor 140 makes it possible to remotely effect attachment and detachment of an implement 14 to and from arms 30 of a loader boom 28 , and that the boom height sensor 232 together with the ECU 212 prevents the operator from inadvertently unlatching the implement when the boom 28 is positioned in other than a safe lowered position, while the various motor operation sensors together with the ECU 212 and the LED indicator 240 inform the operator as to whether there is a jam preventing the motor 140 from effecting desired latching or unlatching operations. [0047] In the event of a failure of the linear electric motor 140 , the motor output shaft 146 can be disconnected from the operating rod assembly 150 by removing one or both of the nut and bolt assemblies 156 and 158 . Operation of the latch rod assembly 124 can then be performed manually. Movement of the operating rod assembly 150 to effect the unlatched arrested position can be accomplished by grasping the handle 168 and pulling outwardly on the operating rod assembly 150 against the bias of the spring 188 until the secondary latch rod 186 is pulled free of the guide slot 164 provided in the left plate 60 . The handle 168 may then be used to pivot the lever arm 166 downwardly so that the operating rod 132 moves to the bottom of the guide slots 164 , with the secondary latch rod 186 then being misaligned relative to the guide slot 164 so as to prevent rightward movement of the operating rod assembly 150 by the compressed spring 188 . The latch rod 172 and latch rod portion 178 are then in respective positions to the left of left and right lugs (not shown) provided at the backside of the implement 14 and disposed between the rod receiving plate 78 and strengthening plate 66 , and between the right receiving plate 72 and strengthening plate 64 . [0048] Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.

A remotely operable latching system is provided for securing an implement to a carrier mounted to a forward end of a lifting arm for pivoting about a horizontal tilt axis. The latching system is mounted to the carrier and includes a latching rod arrangement operated by an extensible and retractable linear electric motor between a retracted latching position and an extended unlatching position. A secondary latch arrangement is provided for rotating the latching rod arrangement to an arrested position preventing movement of the rod arrangement to its latching position once the latching rod is extended to its unlatching position. Movement of the rod arrangement to its arrested position is aided by a spring and by the electric motor. Release of the rod arrangement from the arrested position is done by rolling the carrier back towards the lifting arms bringing the latching rod arrangement into contact with the arm so as to pivot the rod arrangement out of its arrested position. A microprocessor based control unit is coupled to the electric motor and acts in response to a boom height input signals to prevent operation of the motor when the boom is above a preset height. Further, an LED indicator light operates in certain modes which apprise the operator of various operating conditions. For example, the LED light blinks slowly when the latching rod arrangement is being extended to its unlatch position, blinks rapidly if the latching rod jams causing an overload condition and gives a steady light when the latching rod arrangement is fully extended. Various timing requirements are also programmed into the control unit.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS This application is a national stage entry of PCT/GB2009/050741 filed on Jun. 26, 2009, which is a continuation-in-part and claims priority to U.S. patent application Ser. No. 12/147,223 filed on Jun. 26, 2008. This invention relates to a device for handling circular cylindrical tubular objects, with or without intervening bulges or flanges at their ends or intermediate their length. Furthermore it relates to a device that can grip such a tubular object not just for the purpose of lifting the object (in a direction including vertically upwardly in a direction parallel a longitudinal axis of the object), but also for the purpose of applying torque to the object about said longitudinal axis. BACKGROUND The drilling of subterranean wells involves assembling tubular strings, such as casing strings and drill strings, each of which comprises a plurality of heavy, elongated tubular segments extending downwardly from a drilling rig into a wellbore. The tubular string consists of a number of threadedly engaged tubular segments. Conventionally, workers use a labor-intensive method to couple tubular segments to form a tubular string. This method involves the use of workers, typically a “stabber” and a tong operator. The stabber manually aligns the lower end of a tubular segment with the upper end of the existing tubular string, and the tong operator engages the tongs to rotate the segment, threadedly connecting it to the tubular string. While such a method is effective, it is dangerous, cumbersome and inefficient. Additionally, the tongs require multiple workers for proper engagement of the tubular segment and to couple the tubular segment to the tubular string. Thus, such a method is labour-intensive and therefore costly. Furthermore, using tongs can require the use of scaffolding or other like structures, which endangers workers. Others have proposed a running tool utilizing a conventional top drive assembly for assembling tubular strings. The running tool includes a manipulator, which engages a tubular segment and raises the tubular segment up into a power assist elevator, which relies on applied energy to hold the tubular segment. The elevator couples to the top drive, which rotates the elevator. Thus, the tubular segment contacts a tubular string and the top drive rotates the tubular segment and threadedly engages it with the tubular string. While such a tool provides benefits over the more conventional systems used to assemble tubular strings, it also suffers from shortcomings. One such shortcoming is that the tubular segment might be scarred by the elevator gripping dies. Another shortcoming is that a conventional manipulator arm cannot remove single joint tubulars and lay them down on the pipe deck without worker involvement. Other tools have been proposed to cure these shortcomings. However, such tools are often unable to handle tubulars that are dimensionally non-uniform. When the tubulars being handled are not dimensionally ideal, such as by having a varying wall thickness or imperfect circularity of tube section, the ability of tools to adequately engage the tubulars is decreased. There are many other circumstances in which it is desirable to handle other tubular objects. Indeed, the general handling of large pipe sections can be problematic, and a convenient tool for grabbing and loading pipes is desirable. Indeed, very large pipe sections (with a weight in the order of 6000 kN) are frequently provided with lifting and handling handles, but these generally require personnel to ensure appropriate hook up and disconnect. It would be desirable if a pipe could be provided with a simple mechanism for safe connection and disconnection of a lifting device that did not require human intervention at the site of connection. Of course, much smaller pipe sections might be provided with such lifting arrangements. Floor slips are employed on production sites to hold casings and drill pipes being lowered into a well while a new length is connected to the top of the pipe or casing being held. An appropriate design of holder that did not need to open to allow flanges and the like on the casings and drill pipes to navigate through the floor slip, as well as not requiring human intervention in the immediate vicinity of the floor slip during holding and release operations, would be desirable. Emergency disconnect packages are employed to connect rigid risers from subsea installations to surface vessels. Such vessels generally dynamically hold position above a riser but adverse weather conditions and sometimes an inability to maintain position require the possibility of an emergency disconnection from the riser. A device capable performing such function is desirable. PRIOR ART WO2008/085700 discloses a tubular handling apparatus, comprising: a slotted member having a plurality of elongated slots each extending in a direction; a recessed member slidably coupled to the slotted member and having a plurality of recesses each tapered in the direction from a shallow end to a deep end; and a plurality of rolling members each retained between one of the recesses and one of the slots; wherein each rolling member partially extends through the adjacent slot when located in the shallow end of the recess; and wherein each rolling member retracts within an outer perimeter of the slotted member when located in a deep end of the recess. Such apparatus is useful in gripping to both internal and external surfaces of tubulars. However, if the tubular has peripheral extensions then the slotted member cannot necessarily move over such extensions during positioning of the apparatus on the tubular. WO2004/067854 discloses a tool for gripping a tubular object by contact with opposed surfaces thereof comprising a mandrel having means for attachment to lifting gear, at least one pair of gripping assemblies attached to the mandrel, each gripping assembly comprising a body member, a wedge member slidably movable on an individual ramp with respect to the body member towards and away from the mandrel, and a ball or roller cage slidably movable with respect to the wedge member and having at least one ball or roller movable with the ball or roller cage on an inclined ramp with respect to the wedge member thus to grip one of said opposed surfaces of the tubular object to be gripped. An annular array of such gripping assemblies may be attached to the mandrel, each with a wedge member and a ball or roller cage, such that each ball or roller is caused to make annular contact with the wall surface of the object of circular section. Such an arrangement is complex. Moreover, torque cannot be applied through the tool to the object gripped by it. However, it also discloses a plurality of arrays, one above the other. US2005/0160881 discloses a clamping mechanism for applying torque, having two or more jaws that may be opened to allow a tubular to be introduced within the jaws and closed to retain the tubular therewithin. Rollers are located within concave recesses and maintained in spaced apart relationship by biasing means, whereby rotation of tubular may cause the rollers to be wedged between a wall of the recess and the tubular to grip the tubular within the jaws. The clamping mechanism may be utilized as an oil field tubular clamp, a slip, a pipe clamp, and other mechanisms. There is also disclosed a clutch comprising an outer race, a cage, and an inner ring. Recesses are provided in an outer race and accommodate rollers therewith and maintained in spaced apart relationship by the cage. It is an object of the present invention to provide a relatively simple structure that is not only capable of lifting, but also of applying torque when desired. It is another object to provide a device that is capable of permitting large diameter sections of tubular to pass through the device when it is in a release condition without it having to be opened and removed from the tubular. It is a further object to provide a device that can be released rapidly from, and with less force than the clamping force applied by the device in, its locked condition. SUMMARY OF THE INVENTION In accordance with the present invention there is provided a gripping tool in the form of a body having a longitudinal axis and formed by a plurality of sleeves connected end to end, each sleeve including a frusto-conical bore centered on said longitudinal axis; a clamp member in each sleeve formed by clamp-segments, each having side faces, end faces, a frusto-conical exterior surface adapted to match said frusto-conical bore, and a cylindrical interior surface; cage-segments connected to said interior surface and having a plurality of windows partially closing recesses in said interior surface, which recesses are elongate in said longitudinal direction, house a roller and have a base inclined in said longitudinal direction so that, at a lower end of each recess the roller protrudes through said window and at an upper end thereof the roller protrudes less or not at all; a bias mechanism, urging said clamp-segments apart from each other in a peripheral direction; connection means between adjacent clamp segments so that they move together when one is moved axially. Preferably, said connection means is a bolt passing longitudinally through all longitudinally aligned clamp-segments and clamping them together axially. Preferably, a top one each of said clamp-segments has a lift eye by which said clamp elements may be lifted with respect to said sleeves so that said clamp-segments slide up said frusto-conical bore separating from one another in a peripheral direction as they progress. Preferably, a key on one of said frusto-conical surfaces slides in a groove in the other of said frusto-conical surfaces whereby torque applied to said sleeves is transmitted to said clamp-segments. Preferably, said key and slot are parallel the cone angle of said frusto-conical surfaces. Preferably, said key and slot are central in said clamp-segment between said side faces. Preferably, there are three clamp-segments. Preferably, said side faces are planar and disposed in radial planes with respect to said longitudinal axis. Preferably, between a clamp position and an open position of the tool, the segments move from position in which the arcs of the cage segments lie in a common cylindrical surface and the frusto-conical surfaces are flush with each other, to a release position in which said side faces are spaced from one another and said frustoconical surfaces have only line contact between them. Alternatively, said frusto-conical surfaces are inclined part-cylindrical surfaces. Preferably, said sleeves are seated in a hollow housing tube. The tube and sleeves may have between them a key whereby torque applied to the housing is transmitted to said sleeves. Said housing may have a cylindrical bore with an internal ledge at its bottom end, said sleeves being loaded from a top end, a bottom one seating on said ledge and succeeding ones seating on the one below. Preferably, said rollers are balls and said recesses have a semi-circular base of diameter substantially equal to the diameter of the balls. Preferably, said bias mechanism comprises a spring between each facing side face of adjacent clamp-segments. Thus, when said lifting eyes are each attached to a lifting cable that lifts the clamp segments, the segments separate sufficiently to release any tubular clamped between the clamp-segments. That is to say, preferably the angle of inclination with respect to the longitudinal axis of the frusto-conical surfaces is greater than the angle of inclination of the recess bases. The latter is preferably between 3 and 10 degrees, preferably between 5 and 8 degrees. The former is preferably between 10 and 20 degrees, and more preferably between 13 and 16 degrees. Preferably, the tool is designed to clamp on tubular members whose diameter is such that, when the clamp-segments abut one another with mating side faces and the frustoconical surfaces are also mating, the rollers when they evenly contact the tubular are nearer the top end of the recess than the bottom. This provides maximum tolerance while still maintaining the strongest connections between the clamp-segments and sleeves. Of course, should the tubular be larger then it is possible that the rollers may be at the top of their recesses in contact with the tubular and yet the clamp-segments are not in mating contact side face to side face. This is still acceptable since the segments are wedged firmed between the mating cylindrical surfaces of the tubular and their interior surfaces and frusto-conical surfaces (in fact preferably inclined cylindrical) surfaces of the exterior surface of the clamp-segments and the bores of the sleeves. BRIEF DESCRIPTION OF THE DRAWINGS The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. FIGS. 1 a, b and c are respectively, a cutaway perspective view of a two-sleeve gripping tool in accordance with the present invention, a tubular housing, and an exploded view of the tool of FIG. 1 a; FIG. 2 is a side section illustrating general principle of operation of a tool according to the present invention; FIG. 3 is an exploded side view of a clamp segment and assembled view of two others forming a partially complete clamp member used in another embodiment of the present invention; FIGS. 4 a and b are side sections of a four-sleeve gripping tool using the clamp members of FIG. 3 , FIG. 4 a showing the tool in its closed or clamping position and FIG. 4 b showing the tool open; FIG. 5 is a perspective cutaway view of the tool of FIGS. 4 a and b ; and FIG. 6 is a side section illustrating a size benefit of a tool according to the present invention. DETAILED DESCRIPTION It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Moreover, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the first and second features, such that the first and second features may not be in direct contact. Referring to FIGS. 1 a to c , illustrated are perspective views of at least a portion of an apparatus 100 according to one or more aspects of the present disclosure. The tool 100 comprises a tubular housing 110 . Tool 100 is configured to receive and at least temporarily grip, frictionally engage, or otherwise retain a tubular member 105 (shown in FIG. 2 ). For example, the tool 100 may be configured to grip or otherwise frictionally engage an exterior surface of the tubular member 105 . The extent to which the tool 100 engages the tubular member 105 may be sufficient to support a safe working load (SWL) of at least 5 tons. However, other SWL values for the tool 100 are also within the scope of the present disclosure. Furthermore, the extent to which the tool 100 engages the tubular member 105 may also be sufficient to impart a torsional force to the tubular member 105 , such as may be transmitted through a running tool (not shown) from a top drive or other component of a drill string (also not shown). In an exemplary embodiment, the torque which may be applied to the tubular member 105 via the tool 100 may be at least about 6700 Nm (about 5000 ft-lbs), which may be sufficient to “make-up” a connection between the tubular member 105 and another tubular member. The torque which may be applied to the tubular member 105 may additionally or alternatively be at least about 67,000 Nm (about 50,000 ft-lbs), which may be sufficient to “break” a connection between the tubular member 105 and another tubular member. However, other torque values are also within the scope of the present disclosure. The tubular member in question may be a wellbore casing member, a drill string tubing member, a pipe member, a collared tubing member, and/or other tubular elements. The tubular member 105 may be a single tubular section, or pre-assembled double or triple sections. The tubular member 105 may be or comprise a section of a pipeline, such as may be utilized in the transport of liquid and/or fluid materials. The tubular member 105 may alternatively be or comprise one or more other tubular structural members. The tubular member may have an annulus cross-section having a substantially circular cylindrical shape, although approximations thereof may be engaged. The tubular member 105 may not be dimensionally uniform or otherwise ideal. That is, the tubular member may not exhibit ideal roundness or circularity, such that all of the points on an outer surface of the tubular member 105 at a certain axial position may not form a perfect circle. Alternatively, or additionally, the tubular member 105 may not exhibit ideal cylindricity, such that all of the points of the outer surface may not be equidistant from a longitudinal axis 202 of the tool 100 , and/or the tubular member 105 may not exhibit ideal concentricity, such that the axes of all cross sectional elements of the outer surface may not be common to the longitudinal axis 202 . Referring to FIG. 2 , illustrated is a sectional view of at least a portion of an exemplary embodiment of a clamping member 700 of the tool 100 about a tubular member 105 . The clamping member 700 includes a recessed member 210 , a slotted or otherwise perforated cage member 220 , and a plurality of rolling members 230 . The recessed member 210 is substantially cylindrical when formed, having a plurality of recesses 214 therein. The cage member 220 is typically slotted with windows 222 but is not limited to such a configuration. The cage member 220 is fixed to the recessed member 210 , preferably by screws (not shown, although see screws 501 in FIG. 5 ). Each slot or window 222 is configured to cooperate with one of the recesses 214 of the recessed member 210 to retain one of the rolling members 230 . Moreover, each recess 214 and slot 222 is configured such that, when a rolling member 230 is moved further away from the maximum depth 214 a of the recess 214 (that is, to a lower end 232 of the recess), the rolling member 230 protrudes further through the slot 222 and beyond an inner perimeter 224 of the slotted member 220 , and when the rolling member 230 is moved towards the maximum depth 214 a of the recess 214 (that is, to an upper end 234 ), the rolling member 230 also moves towards a retracted position within the inner perimeter 224 of the slotted member 220 . That is to say, the bases 236 of the recesses are inclined with respect to the longitudinal axis 202 and are inclined inwardly and downwardly with respect to the normal orientation of the tool in use (which is as shown in FIG. 2 ). Each slot 222 may have an oval or otherwise elongated profile, such that each slot 222 is greater in length than in width. The length of the slot 222 is in the direction of the longitudinal axis 202 of the tool 100 . The walls of each slot 222 may be tapered radially inwardly. Each recess 214 may have a width (into the page in FIG. 2 ) that is at least about equal to or slightly larger than the width or diameter of each rolling member 230 . Each recess 214 may also have a length that is greater than a minimum length of the slot 222 . The width or diameter of the rolling member 230 is at least larger than the width of the internal profile of the slot 222 . Because each slot 222 is elongated in the direction of the taper of the recesses 214 , each rolling member 230 may protrude from the slotted member 220 an independent amount based on the proximate dimensional characteristics of the tubular member 105 . For example, if the outer diameter of the tubular member 105 is smaller near the end 105 a of the tubular member 105 , the rolling member 230 located nearest the end 105 a of the tubular member 105 protrudes from the slotted member 220 a greater distance relative to the distance which the rolling member 230 nearest the central portion of the tubular member 105 protrudes from the slotted member 220 . Each of the rolling members 230 may be or comprise a substantially spherical member, such as a steel ball bearing. However, other materials and shapes are also within the scope of the present disclosure. For example, each of the rolling members 230 may alternatively be a cylindrical or tapered pin configured to roll up and down the ramps defined by the recesses 214 . Referring to FIG. 3 , illustrated is an exploded perspective view of the clamping member 700 of FIG. 2 . From FIG. 3 , it can be seen that the clamping member 700 actually comprises (in this embodiment) three clamping segments 700 a,b,c , segment 700 a of which is shown exploded and separated from the other two. From this it can also be seen that the slotted cage member 220 and recessed member 210 are likewise each in three segments. The tool 100 also includes a holder 740 which also comprises three discrete sections 740 a,b,c . Other functionally equivalent configurations may combine holders 740 a,b,c and recessed member 210 a,b,c to create an integral member in each case. Each holder section 740 a,b,c may include a flange 745 configured to be coupled with a flange 745 of another of the holder sections 740 a,b,c , such that the holder sections 740 a,b,c may be assembled to form a bowl-type structure configured to hold the recessed sections 210 a,b,c of the recessed member 210 , as well as sections 220 , and the rolling members 230 . FIGS. 4A and 4B are side sectional views of the clamping member 700 shown in FIG. 3 in engaged and disengaged positions, respectively. Referring to FIGS. 4A and 4B collectively, with continued reference to FIG. 3 , the tool 100 includes multiple clamping members 700 stacked vertically. Hereinafter, the clamping members 700 may also be referred to as vertical segments to reflect their vertically stacked arrangement. In the exemplary embodiment shown in FIGS. 4A and 4B , the apparatus 100 includes four vertical segments 700 . In other embodiments, however, the apparatus may include fewer or more segments. The gripping force applied by the apparatus to the tubular member is at least partially proportional to the number of vertical segments (clamping members) 700 , such that increasing the number of segments 700 increases the lifting capacity of the apparatus 100 , as well as the torque which may be applied to the tubular member by the apparatus. Each of the vertical segments 700 may be substantially similar or identical, although the top and bottom segments 700 may have unique interfaces for coupling with additional equipment between a top drive (not shown), for instance, and the casing string. Indeed, bottom clamping member 700 d is shown with an additional skirt 760 to receive bottom holder 740 d , as described further below. The external profile of each holder 740 is tapered at 770 in a frusto-conical fashion, (although, preferably, the frusto-cone is the special case of a circular cylinder and, instead, the axis of the cylindrical surface 770 is merely inclined towards (and so as to intersect) the longitudinal axis 202 of the tool), such that the lower end of each holder 740 has a smaller diameter than its upper end. Each vertical segment 700 of the apparatus 100 also includes a tubular housing sleeve 750 having an internal profile configured to cooperate with the external profile 770 of the holder 740 such that as the holder 740 moves downward (relative to the housing sleeve 750 ) towards the engaged, clamping, position ( FIG. 4 a ) the holder 740 constricts radially inward. Yet, when the holder 740 moves upward, towards the disengaged position ( FIG. 4 b ) the holder 740 expands radially outward. The top segment 700 a of the apparatus 100 may include an interface (hook eye) 760 configured to couple with one or more hydraulic cylinders and/or other actuators (not shown). Moreover, each holder 740 is coupled to its upper and lower neighboring holders 740 . Consequently, vertical movement urged by the one or more actuators coupled to the interface 760 results in simultaneous vertical movement of all of the holders 740 . Accordingly, downward movement of the holders 740 driven by the one or more actuators causes the rolling members 230 to engage the outer surface of the tubular member 105 , whereas upward movement of the holders 740 driven by the one or more actuators causes the rolling members 230 to disengage the tubular member 105 . The force applied by the one or more actuators to drive the downward movement of the holders 740 to engage the rolling members 230 with the tubular member 105 is one example of a preload that can be applied in order to pre-grip the tubular member 105 if gravity is not available to press the holder downwardly. Referring back, now, to FIGS. 1 a, b and c , tool 100 is a two-section tool, having two clamping members 700 d,e vertically aligned. Tubular housing 110 here comprises a simple tube having a bottom internal flange 152 on which external flange 154 of bottom housing 750 d seats. Bottom flange 156 of top housing 750 e seats on top edge 158 of bottom housing 750 d . A key 170 is fixed internally of the housing 110 by bolts 171 and slides in axially extending slots 172 on the outside of the housing sleeves 750 d,e . Torque can then be transmitted by the housing 110 to the sleeves 750 d,e. Each vertically aligned holder 740 is interconnected by a pair of bolts 160 . A spacer 162 and spring 164 being disposed between them and the connection being completed by a lock nut 166 that, when tightened, permits some relative vertical movement between holders 740 . The purpose of this is to permit each clamping member 700 d,e to independently clamp on the tubular member 105 . In use, tubular member 105 is inserted from underneath the tool 100 . Prior to this, the holders 740 have been lowered into the tubular housing 110 and sleeves 750 d,e so that they collapse inwardly to the clamping position depicted in FIG. 4 a where radial faces 168 of adjacent holder sections 740 a,b,c abut one another. In this position, the cage members 220 and internal face of the holders 740 (which here constitute also the recessed member 210 of FIG. 3 described above) are essentially on surfaces of the same cylinder. This cylinder coincides with the design cylinder of tubular members 105 the tool is intended to handle. However, when inserted from underneath, the tubular may not be absolutely true. Indeed, the internal frusto-conical surfaces of the housing sleeves 750 d,e or the corresponding external surfaces 770 of the holders 740 might exhibit some tolerance. Finally, the pickup by the rollers 230 may also show some variation. These differences are to some extent accommodated and shared between the two clamp members 700 d,e when a small freedom of movement between them is permitted, as provided by the bolts 160 . Thus, when inserted from underneath and then the tubular housing 110 is lifted, the rollers 230 progressively bite into the tubular member 105 . Some rollers 230 may not bite to the same extent as others, and the partial separation of the holders 740 permits some tolerance to be accommodated. The holders have said frusto-conical external surfaces 770 , as described above. These mate with corresponding frusto-conical internal surfaces 752 of the housing sleeves 750 . The surfaces 770 include keys 742 that fit in slots 754 in the housing sleeves 750 . If the surfaces 770 , 752 are truly conical, then they only mate in area contact in one axial position, which is arranged to be when the radial faces 168 of the holder sections 740 a,b,c abut. In this event, as the holders 740 rise up, only a line contact remains between the surfaces 770 , 752 . Accordingly, it is preferred, as stated above, that the engaging surfaces 770 , 752 are inclined cylindrical surfaces, in which event there is area contact in all axial positions. However, since there is only load applied when the holders 740 are in their clamp position, it is not a significantly important point. However, the keys 742 are preferably central in each holder 740 . The keys 742 transmit torque between the housing sleeves 750 and the holders 740 . When a tubular member 105 is to be released by the tool 100 , the weight of the tubular member 105 is taken from the tool 100 by other means (not shown). These means may simply comprise the tubular member 105 reaching a limit of travel after being lowered into a well bore. Alternatively, such means may comprise a floor slip arrangement (that may itself take the form of a tool according to the present invention). When the weight has been released, the holders 740 are lifted within the housing sleeve 750 . When the holders 740 rise relative to the housing sleeves 750 , springs 780 press the radial faces 168 apart. The tapered surfaces 770 , 752 of the holders 740 and housing sleeves 750 allow the clamp segments to spread significantly, whereby not only is the tubular member 105 released, but also enlargements that may be in the tubular member 105 can pass through the tool 100 . This is frequently the case in drill strings where connections between adjoining drill pipe sections may have an enlarged diameter. The taper on the surfaces 770 , 752 is preferably about 15 degrees with respect to the longitudinal axis 202 . Although shown much greater in FIG. 2 , the inclination of the bases of the recesses 214 to the longitudinal axis is only about 10 degrees. The effect of this is that lifting the holders 740 immediately releases the clamping pressure without requiring significant force. Indeed, the arrangement is such that, in some applications, it is unnecessary to relieve the load of the tubular member 105 before releasing the tool 100 . Such may be required in emergency situations. Indeed, umbilical connections between undersea installations and surface vessels often must be suddenly released and the present arrangement provides this capacity. An advantage provided by dividing the clamping members 700 into short vertical sections is that the inclined surface needed to support a sufficiently long axial length for the holders 740 to attain sufficient grip on the tubular member 105 for the loads being envisaged can be provided in a relatively restrained diameter. FIG. 6 illustrates the profile 600 that a single vertical section tool would need to have if it were to have the same gripping power of a twin-section tool 100 as shown in FIGS. 1 a,b and c . This is achieved simply by extending the taper 602 of the lower section as it would need to proceed if only a single clamp section was employed. Not only would this increase the dimensions of the tool (from diameter d to D in FIG. 6 ) but also the mass of the tool would commensurately be increased. Indeed, by constructing the housing from several components (the tubular housing 110 and housing sleeves 750 ) a particularly compact design is achieved, and one that is relatively easy to manufacture since there are few undercuts to be made. Each holder section 740 a,b,c therefore has said frusto-conical external surface 770 (within the meaning of which is included inclined cylindrical or other approximation thereof) radial faces 168 (which in the arrangements illustrated are in radial planes, but this is not essential—therefore, the radial faces 168 may also be referred to as side faces) abutting end faces (see top face 743 in FIGS. 1 a and c on which said lifting eyes 760 are fixed) and cylindrical and recessed internal face 746 (not visible except in FIGS. 2 and 3 ), which may be constituted in a separate component 210 . The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions and alterations herein without departing from the scope of the present disclosure. For example, embodiments of the invention, with suitable adaptation that would be evident to the person skilled in the art, have applications not limited to floor slips, handling apparatus and emergency disconnect devices. In the case of floor slips, for example, the release of the tubular is easily and quickly effected by lifting the clamping members within the tubular housing sleeve. The spread of the individual segments on such lifting opens the aperture through the tool so that bulges and other flanges on the drill pipe or casing being controlled by the floor slip can pass through the tool without the need to open the tool and remove it laterally from the tubular. In the case of handling equipment generally, or specifically for large pipe sections, for example, a simple tube or rod can be provided as a handle to be gripped by the tool of the present invention. Indeed, a flange can be disposed on the end of the handle in the event that the grip of the tool should falter or fail and whereby the flange will catch on the upper surface of the holder and press it into tighter engagement with the handle. In the locked position of the holder, the flange would be unable to pass through the tool, whereby a safety mechanism is provided. However, when the tool is released in normal operation by the holder being lifted in the housing sleeve, the spread of the clamping members opens the passage between them so that the flange on the handle could be accommodated to effect normal release (and engagement) of the tool from (and with) the handle. In the case of emergency disconnect packages, the force needed to lift the holder is much less than the clamping force effect by the holder on the tubular it is gripping, whereby rapid disconnection is facilitated. Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise. Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference. REFERENCE NUMERALS 100 —tool capable of lifting and applying torque 105 —tubular abutment/tubular member 105 a —end of tubular member 105 110 —tubular housing (of tool 100 ) 152 —bottom internal flange (of tubular housing 110 ) 154 —external flange (of bottom housing 750 d ) 156 —bottom flange (of top housing 750 e ) 158 —top edge (of top housing 750 e ) 160 —bolts (used in connecting vertically aligned holders 740 ) 162 —spacer (used in connecting vertically aligned holders 740 ) 164 —spring (used in connecting vertically aligned holders 740 ) 166 —lock nut (used in connecting vertically aligned holders 740 ) 168 —radial or side faces (of adjacent aligned holders 740 ) 170 —key (of tubular housing 110 ) 171 —bolts (affixing key 170 to tubular housing 110 ) 172 —axially extending slots (on outside of housing sleeves 750 d,e ) 202 —longitudinal axis (of tool 100 ) 210 —recessed member (of clamping member 700 ) 210 a,b,c —individual segments of recessed member 210 214 —recesses (of recessed member 210 ) 214 a —maximum depth of recesses 214 220 —(slotted or otherwise) cage member (of clamping member 700 ) 222 —windows/slots (of cage member 220 ) 224 —perimeter of slotted member 220 230 —rolling members (of clamping member 700 ) 232 —lower ends of recesses 214 234 —upper ends of recesses 214 236 —bases of recesses 214 501 —screws (fixing cage member 220 to recessed member 210 ) 700 —clamping member/vertical segments 700 a,b,c —individual segments of clamping member 700 700 d —bottom clamping member/vertical segment 740 —holder (of tool 100 ) 740 a,b,c —discrete sections of holder 740 742 —keys (of external surfaces 741 of holders 740 ) 743 —top face or abutting end face of (top) holder 740 745 —flange of each section 740 a,b,c of holder 740 750 —tubular housing sleeve (of each vertical segment 700 ) 750 d —bottom tubular housing sleeve 750 e —top tubular housing sleeve 752 —frusto-conical external surfaces (of holders 740 ) 754 —keys (of external surfaces 741 of holders 740 ) 760 —skirt (of bottom clamping member 700 d ) 770 —tapered, cylindrical, external profile (of each holder 740 ) 780 —springs (that press radial faces 168 apart)

A tubular member handling apparatus is a gripping tool ( 100 ) in the form of a body ( 110 ) having a longitudinal axis ( 202 ) and formed by a plurality of sleeves ( 750 ) connected end to end, each sleeve including a frusto-conical bore 752 centered on said longitudinal axis; a clamp member ( 700 ) in each sleeve formed by clamp-segments ( 740 ), each having side faces ( 168 ), end faces ( 743 ), a frusto-conical exterior surface ( 741 ) adapted to match said frusto-conical bore, and a cylindrical interior surface ( 745 ); cage-segments ( 220 ) connected to said interior surface and having a plurality of windows ( 222 ) partially closing recesses ( 214 ) in said interior surface, which recesses are elongate in said longitudinal direction, house a roller ( 230 ) and have a base ( 236 ) inclined in said longitudinal direction so that, at a lower end ( 232 ) of each recess the roller protrudes through said window and at an upper end ( 234 ) thereof the roller protrudes less or not at all; a bias mechanism 780 , urging said clamp-segments apart from each other in a peripheral direction; connection means ( 160 ) between adjacent clamp segments so that they move together when one is moved axially.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority from U.S. Provisional Patent Application Ser. No. 61/319,906 filed on Apr. 1, 2010 which is incorporated by reference herein for all it discloses. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to motors used in downhole drilling applications, and in particular, to downhole drilling motors that may be subjected to unusually high levels of bending stress, such as used in very deep and very extended lateral drilling operations. The downhole motor described herein has internal structures intended to improve its reliability and lengthen its intervals between servicing. 2. Description of the Related Art Downhole drilling motors used in the oil and gas drilling industry typically include a drive shaft assembly connected between a power section and a bearing section. The drive shaft transfers torque from the eccentrically rotating power section to the concentrically rotating bearing assembly to rotate a drill bit as it is pushed against the earthen formation, effecting a drilling action. The motor is often configured such that the axis of the power section is angularly offset from the axis of the bearing section and drill bit. The driveshaft assembly may include universal joints, or alternately ‘flex’ joints, on either end to accommodate the mis-alignment of the axes during a drilling operation while allowing transfer of torque from the power section of the motor through the bearing assembly and out to the drill bit. During operation, drilling motors are often subjected to extreme, cyclic bending loads, and also rapidly varying compressive loads. In these applications, it may be difficult to maintain the internal components of drilling motors in their proper orientations. Shifting of these components during operation may result in sudden, premature and catastrophic failure of the motor. A stabilizer is a drill string component well known in the art that typically has a plurality of blades, or raised portions of material, that extend radially outward from a main tubular body. The blades may extend to a diameter that is slightly less than the diameter of the wellbore. This configuration may permit the stabilizer to travel through the wellbore, while ensuring that the axis of the stabilizer is kept nearly concentric to the axis of the wellbore. The deflection of the drill string at the stabilizer location may, therefore, be limited to that permitted by a gap between the stabilizer blades and the wellbore. Because the outer surfaces of the blades may continually contact the wellbore due to side loading, these surfaces may be coated with abrasion-resistant material to reduce wear. The areas between the blades may form open channels that provide pathways to allow annular flow to pass by the stabilizer. One type of stabilizer is a drill string component having top and bottom connections that connect to upper and lower components within the drill string. Another type of stabilizer is in the form of a threaded sleeve that threads to the outer diameter (OD) of one of the drill string components; for example, the lower stabilizer of a mud motor which is typically threaded to the OD a bearing assembly housing. The threaded sleeve option may allow interchangeability between stabilizers of different diameters, depending on the hole size and the amount of clearance desired. Despite the advancement in drilling technology, there remains a need for advanced techniques for reinforcing drilling equipment. The present invention is directed at providing such advanced techniques. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a very general and generic arrangement of a typical drilling rig for drilling boreholes into the earth. FIG. 2 is a partial cross-section view of a threaded connection portion of a downhole motor of the present invention, illustrating the general arrangements of the individual components making up the connection. FIG. 3 is magnified partial section view showing in greater detail the arrangement of selected components of the threaded connection portion of a downhole motor of the present invention as shown in FIG. 2 , and in particular one arrangement of locking collet members of the present invention. FIGS. 4 and 5 are views of the arrangement of the locking collets members used to both preload and stiffen the threaded connection portion of a downhole motor of the present invention as shown in FIGS. 2 and 3 . BRIEF SUMMARY OF THE INVENTION In a typical bottom hole assembly (also known as a BHA) comprising a mud motor, the upper end of the power section stator is connected to a top sub (sometimes referred to as ‘housing’ or ‘motor housing’) which connects to the drill string components above. The connection between the top sub and stator may be susceptible to fatigue damage due to bending loads experienced during drilling operations. This connection can be exposed to excessive cyclic bending loads due to its location and the dynamics of the drill string during operation; however, the connection strength may be limited due to manufacturing and design limitations on the size and thickness of the stator tube. Disclosed herein is a new drilling motor that addresses this issue by providing an external means to strengthen and support the connection during drilling operations. Further disclosed is an apparatus that may improve the bending strength of a threaded connection, and in particular the top connection of the stator in a mud powered borehole drilling motor assembly, which may be susceptible to fatigue damage due to bending loads experienced during the drilling operations. The invention further encompasses a threaded sleeve stabilizer having a threaded sleeve that connects to the outside diameter (OD) of a “top sub” used with the above described motor. The stabilizer's threaded sleeve may be located axially over the threaded connection between the top sub and stator. The lower end of the stabilizer's threaded sleeve may have an internal bore that is located along the stator, outside of the stator tube below the stator box. An annulus may be created between the internal bore of the stabilizer's threaded sleeve and the OD of the stator which provides a chamber to receive a plurality of wedge like devices, hereinafter called ‘collets’. Either the outer surface of the collets, or an inner surface within the stabilizer bore of the threaded sleeve, or both, may be tapered such that axial force on the bottom of the collets will cause the collets to be wedged between the outside of the stator of the motor and the inside of the stabilizer's threaded sleeve. The collets described herein may have an internal wedge configuration to secure the internal components. The wedge collets may be made of a material having a lower modulus of elasticity than the motor housing. Alternately, the collets may have the same modulus of elasticity, but have a significantly lower hardness than the motor housing. Alternately, the collets may be sized and shaped such that they will operate effectively regardless of their composition or material properties. The wedge shape may be used to help assure that the internal components remain in proper position during operation, and thus help to maintain their relative position within the motor during operation. The lower end of the stabilizer's threaded sleeve may have a threaded box located below the collets into which is threaded a locking sleeve which, when makeup torque has been applied, contacts the collets and provides axial force to wedge them upward between the threaded sleeve and the stator. The wedged collets firmly secure the lower end of the threaded sleeve of the stabilizer to the stator while the upper end of the threaded sleeve of the stabilizer is secured to the top sub through the threaded connection therebetween. This arrangement effectively adds stiffness to the threaded connection between the top sub and stator. In addition, the OD of the threaded sleeve of the stabilizer may be closely sized to the borehole diameter, limiting deflection of the BHA at that location and providing further stability to the stator and top sub connection during drilling operations. In one aspect, therefore, a wedge arrangement formed from a plurality of collets may be disposed intermediate the stator and the motor housing. In this configuration the wedge arrangement may include one or more collets. Each collet may be distinct from each other so as to be individually fitted into the motor so as to be independent of each other. They may have generally the same width, or alternately, the collets may be of varying widths to accommodate assembly. Further disclosed is a downhole motor adapted for drilling boreholes into the earth having a compression loaded retention device. A number of separate collets may be loaded in compression between the stator and the housing of the motor, and are held in compression by a threaded connection. The collets may be used for the maintaining the compressive loading of the components at a thrust bearing end of a driveshaft assembly for a downhole motor. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows a very schematic representation of a drill string 2 suspended by a derrick 4 for drilling a borehole 6 into the earth for minerals exploration and recovery, and in particular petroleum. A bottom-hole assembly (BHA) 8 is located at the bottom of the borehole 6 . Oftentimes, the BHA 8 may have a downhole drilling motor 9 to rotate a drill bit 1 . As the drill bit 1 is rotated by the downhole motor 9 , it drills into the earth allowing the drill string 2 to advance, forming the borehole 6 . For the purpose of understanding how these systems may be operated for the type of drilling system as illustrated in FIG. 1 , the drill bit 1 may be any one of numerous types well known to those skilled in the oil and gas exploration business. This is just one of many types and configurations of bottom hole assemblies 8 , however, and is shown only for illustration. There are numerous arrangements and equipment configurations possible for use for drilling boreholes into the earth, and the present disclosure is not limited to the particular configurations as described herein. As shown in FIG. 2 , the invention disclosed herein may employ a locking (or threaded) sleeve stabilizer 37 that spans an upper stator connection 39 and is secured to a top sub 14 and a stator 10 , for providing additional stiffness to the connection while limiting drill string deflection at this location. The downhole drilling motor 9 of FIG. 1 may comprise the stator 10 , as shown in FIGS. 2 and 3 . Typically, there is a long tubular body component of the mud motor 9 power section 12 , as shown in FIG. 2 . During drilling operations, certain conditions can lead to excessive cyclic bending loads at the upper and lower threaded connections, which can ultimately lead to fatigue failure. The component of the motor 9 that the top or bottom of the stator 10 is connected to is known as the motor housing 20 (e.g., top sub 14 , lock housing). The motor housing 20 is fitted with external threads 22 and an upset 24 for a stabilizer sleeve 30 of the locking sleeve stabilizer 37 to thread onto and shoulder against. An additional component of the drilling motor 9 of the present invention is the stabilizer sleeve 30 . The stabilizer sleeve 30 is a threaded sleeve with a plurality of blades 35 that protrude radially outward. Like any drill string stabilizer, as is well known in the art, the blades 35 extend to a diameter that is slightly less than the diameter of the wellbore, which permits the threaded sleeve stabilizer 37 to travel through the wellbore 6 while ensuring that the axis of the threaded sleeve stabilizer 37 is kept nearly concentric to the axis of the wellbore 6 . The blades 35 may be aligned axially with the end connection of the stator 10 , limiting the deflection of the end of the stator 10 to that permitted by a gap between the stabilizer blades 35 and the wellbore 6 . Because the outer surfaces of the blades 35 may continually contact the wellbore 6 due to side loading, these surfaces may be coated with abrasion-resistant material to reduce wear. The areas (not shown) between the blades 35 form open channels that provide pathways for annular flow to pass by the threaded sleeve stabilizer 37 . The stabilizer sleeve 30 is threaded at both ends. The first end is rigidly secured to the external threads 22 along the body of the motor housing 20 . The second end is located along the OD of the stator 10 . The internal bore of the stabilizer sleeve 30 provides an annular region along the outside of the stator 10 , into which is inserted a plurality of collets 50 , as shown in more detail in FIGS. 4 and 5 . A locking sleeve 40 wedges the collets 50 between the stabilizer sleeve 30 and the stator 10 . In these Figures, the collets 50 are illustrated as fitting together as a smooth cylinder that forms a generally cylindrical ring. However, it is contemplated that these collets 50 may have any one of a variety of shapes, and do not necessary present a smooth outside or inside wall to their mating surfaces. Furthermore, the individual collets do not generally need to have smooth outside surfaces, and may be grooved or roughened on the inside or outside to facilitate fitting. Finally, although the collets 50 as illustrated all have approximately the same width, they may be formed so as also being varied in width. Also, it is also possible that one or some of the collets 50 may be formed from a material different from the other collets 50 , and that material may have a hardness or modulus of elasticity differing from the other collets 50 , or from the material of the stator 10 or locking sleeve 40 . Preferably, however, the collets 50 as illustrated are made of steel and machined to shape. Alternately, it may be desirable to form the collets 50 in a casting, forging or one of many other well known forming processes. Referring to FIGS. 2 and 3 , the ends of the stabilizer sleeve 30 may be firmly secured along either side of the stator 10 end connection by the collets 50 . The stiffness of the stabilizer sleeve 30 thus may be used to add rigidity to the end connection of the stator 10 , for lowering the cyclic bending stresses induced at this location during drilling operations and providing protection against fatigue failure. This new motor design, which incorporates the threaded sleeve stabilizer 37 , may be used to improve the bending strength of the threaded connection. For example, the threaded sleeve stabilizer 37 may be used in the top connection of the stator 10 in the mud motor assembly 9 , which may be susceptible to fatigue damage due to bending loads experienced during drilling operations. Furthermore, the threaded sleeve stabilizer 37 , as disclosed herein, may connect to the outside diameter of the top sub 14 in the bottom hole assembly 8 . The threaded sleeve stabilizer 30 may be located axially over the threaded connection between the top sub 14 and stator 10 . The lower end of the stabilizer 30 may have an internal bore that is located along the outside of the stator 10 tube below the stator 10 box as shown in FIG. 2 . An annulus may be created between the internal bore of the stabilizer 30 and the OD of the stator 10 which provides a chamber to receive the plurality of collets 50 . As shown in FIG. 3 , either the outer surface of the collets 50 , or an inner surface within the stabilizer 30 bore, or both, may be tapered such that axial force on the bottom of the collets 50 will cause the collets 50 to be wedged between the outside of the stator 10 and the inside of the stabilizer 30 . The lower end of the stabilizer 30 has a threaded box located below the collets 50 into which is threaded the locking sleeve 40 which, when makeup torque has been applied, contacts the collets 50 and provides axial force to wedge them upward between the stabilizer 30 and the stator 10 . The wedged collets 50 firmly secure the lower end of the stabilizer 30 to the stator 10 while the upper end of the stabilizer 30 is firmly secured to the top sub 14 through the threaded connection therebetween, which effectively adds stiffness to the threaded connection between the top sub 14 (as shown in FIG. 2 ) and stator 10 . In addition, the OD of the stabilizer 30 is closely sized to the hole diameter of the wellbore, limiting deflection of the BHA at that location and providing further stability to the stator 10 and top sub 14 connection during drilling operations. Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications apart from those shown or suggested herein, may be made within the scope and spirit of the present invention. While the present disclosure describes specific aspects of the invention, numerous modifications and variations will become apparent to those skilled in the art after studying the disclosure, including use of equivalent functional and/or structural substitutes for elements described herein. For example, while certain embodiments have been described, modifications thereof can be made by one skilled in the art without departing from the scope or teachings herein. For example, the collets may be of various shapes and materials to provide the desired results. Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter.

A threaded sleeve stabilizer spans an upper stator connection in a mud driven drilling motor used for borehole drilling. A number of collets are loaded in compression between the stator and the housing of the motor, and are held in compression by a threaded connection.

You are an expert at summarizing long articles. Proceed to summarize the following text: The present application is a National Stage Filing Under 35 U.S.C. 371 of International Application Serial No. PCT/TT10/00001, filed Aug. 13, 2010. The entire above-referenced patent application is incorporated herein by reference. BACKGROUND OF THE INVENTION The present Invention relates to a multifunctional screw drill and reaming device, for the testing of the structure and composition of various soil types, as well as for sampling and boring, extracting and injecting of gases and various types of chemicals as well as liquids, slurry, granules and solids. FIELD OF THE INVENTION The present invention relates to a multifunctional screw drill and reaming device, intended for use in the testing of the structure and composition of various soil types. The present invention consists of a primary screw and secondary screws, both sets of screws being independently driven. Screws can be hydraulically, pneumatically, mechanically, electrically, or manually driven. Sections of primary and secondary parts may be added for achieving greater depth and soil penetration. DESCRIPTION OF THE PRIOR ART Soil depth, time of sampling and the number of separate samples making up a composite sample, need to be standardized for the range of tests required. Nevertheless there is often a pragmatic and economical need to be flexible on the ideal standards for each test, so that desired tests may be carried out on a single retrieved sample. Good sampling tools have been described as those that should: 1. take a small enough equal volume of soil from each sub-sample site so that the composite sample will be of an appropriate size to process for analysis; 2. be easy to clean; 3. be adaptable to dry sandy soil as well as moist sticky soil; 4. be relatively easy to use and thus provide for fairly rigid sampling of a field; 5. provide uniform cores or slices of equal volume at all spots within the composite area (James & Wells 1990). Sampling soil tools have been classified into: (a) blades (includes trowels, spades, shovels, spoons and knives); (b) tubes (includes open-sided, plain-cylinder, constricted-tip and uniform-bore); (c) augers (includes wood-bit, post-hole and sheathed) (Cline 1944). Many of these sampling tools will not meet the requirements for good sampling tools. Blade-type tools will often take tapered slices of soil unless held strictly vertical. Tapered slices or cores may bias the analysis as they will generally give an uneven weighting of soil in favour of the enriched surface. In stony soils and heavy clay sub-soils, augers may be the only tool that can penetrate the medium. However, they will not take uniform cores and can easily cross-contaminate soils from different depths or horizons. In general, assessment to tube samplers has been favorable (Brown 1965; Vimpany 1966; Hennig & Schaffter 1973; Terry et al, 1974; Vimpany & Bradley 1980) and they are the preferred sampling tool to use wherever possible. A few studies have been conducted on the effect of core diameter on soil test variability and have generally found that variation decreases with increasing diameter (Skene & Hosking unpubl. data). This would indicate that fewer cores per site may need to be taken when using large-diameter samplers or, conversely, more cores are required with small-diameter samplers. However, there is a limit to the diameter of a tube sampler that should be used in field sampling. Large diameter cores rapidly increase total sampling volume and may cause practical problems in sample transport and handling. There is necessarily a compromise between the number of cores that should be taken for a composite sample and the total volume of soil in a composite that can be effectively handled either in the field or during the laboratory preparation without introducing further error associated with sub-sampling (McIntyre 1967). Sampling tools are often constructed from stainless steel. Other metals can be a cause of contamination, which is of concern where trace elements analyses are to be performed. Lubricants are sometimes used, particularly on deep-core sampling tubes but can cause error in organic carbon analysis (Dowling et al, 1985). Manually operated sampling tools allow the operator to examine each sample individually before acceptance and enable modification to the sample extraction, if necessary. For example, as depth of sampling is often critical, it is important to ensure that a full core is extracted (i.e. the bottom part of the core has not broken off and fallen from the sampler). In dry sandy soils or cultivated land, the sampler may need to be forced into a near-horizontal position, while still in the ground, before being listed out. Mechanically driven sampling tools are increasingly being used to ease the sampling process, particularly where sub-surface samples are required (Bolland et al. 1994). When using such apparatus, it is important to take some trial samples first to ensure that the full soil depth required is being collected and that distortion of each sub-sample does not occur. For example, in a wet plastic soil or dry cultivated soil, surface compression by the sampler may result in non-standard depths being sampled. In addition, unless operators take care, mechanical samplers operated from vehicles may sample atypical spots (e.g. dung, fertilizer granules), as would analysis of samples of soil from different paddocks or blacks on a farm often give different results (Robertson & Simpson 1954; Grayley et al. 1960) Hosking 1986c). This is particularly so for nutrients such as extractable phosphorus or extractable potassium and can generally be related to differing soil sub-strata. The Model 0200 Soil Sampler allows the extraction of intact soil cores. A core 2-¼″ (5.7 cm) in diameter is extracted and held in a brass cylinder. The cylinder and soil sample can then be placed in a pressure plate extractor or Tempe cell apparatus, and the water-holding characteristics of the sample can be determined. The cylinder can be used to provide a sample of known volume, allowing the bulk density to be determined. The sampler is supplied with two wedge coring tips, driving hammer, core extractor, spanner and strap wrench for replacing coring tips, six cylinder caps, and five brass cylinders; one 6 cm long, two 3 cm long, and two 1 cm long. The Model 0212 Soil Sampler allows the extraction of intact soil cores. A core 3-½″ (8.9 cm) in diameter is extracted and held in a brass cylinder. The cylinder and the soil sample can then be placed in a pressure plate extractor or Tempe cell apparatus and the water-holding characteristics of the sample can be determined. The cylinder can be used to provide a sample of known volume, allowing the bulk density to be determined. The sampler is supplied with two wedge coring tip, hammer, spanner wrench for replacing coring tips, and six brass cylinders; two 6 cm long and four 3 cm long. The Model 0215 Soil Sampling Tube produces a smooth-walled hole, 1-¼″ (3.2 cm) in diameter, while extracting a soil sample ¾″ (1.9 cm) in diameter. The optional drop hammer is used to help insert the sampler into the soil, and to remove the sampler and extract a soil sample. An optional Puller Jack, Model 0220, is available to aid in removing the sampler from the soil. The Lord Soil Sampler is 3 feet (0.91 m) in overall length and 1 inch (2.5 cm) in diameter and is made from tough, chrome-moly steel. A one-foot opening on the side permits easy removal of the sample from the polished, nickel-plated unit. The coring tip is replaceable and fabricated from heat-treated nickel-plated tool steel. The handle unscrews at the top to permit addition of a 2-foot (0.68 m) extension tube for deep sampling. The sampler, as well as extension tube, is marked at 6″ (15.2 cm) intervals for depth measurements. LYNAC® Sampler is an industry standard split barrel sampler. It includes a shoe, barrel and head with optional “fast threads” to speed assembly and disassembly. Optional tapered threads (AWJ). Normally driven by a 140 lb. Safety Hammer, an In-Hole Sampling Hammer or SPT Automatic Hammer. The sampler barrel has a tongue and groove design to facilitate reassembly of the barrel and a heat-treated shoe to better withstand severe driving conditions. In addition, a ball check valve prevents wash-out during removal from the hole and the shoe design accommodates a Flap Valve or Spring Retainer. This split tube sampler is designed for taking soil samples at the bottom of the cleaned bore hole by the drive weight method. The split section is held together with a ball check head and a hardened steel drive shoe. The ball check feature in the head prevents samples from being washed out of the sampler upon withdrawal from the hole. The sampler is designed to accommodate a brass, plastic, or paper tube liner for collecting and carrying samples to the field office. Two sample lengths are available. Noting steps in tube design, Drilling World's heat treated drive shoe is recessed to accommodate various accessories. All assemblies are designed to accommodate liners which facilitate transportation of samples to laboratory without disturbing soil samples. MI-purpose sampler used for visual classification, contamination content and moisture determination. The split barrel permits removal of a sample as it is taken from the ground. Generally driven by a 140 lb (63.5 kg) safety hammer, an in-hole sampling hammer or SPT Automatic Hammer. Samplers are available with both standard and (AWJ) thread design. Sizes are identified by sampler O.D. The “Shelby” Tube sampler is the simplest and probably most widely used of the “in-situ” quality samplers. It consists of a head section which contains a check valve and drill rod box connector and a thin wall sample tube. The tube is loosely attached to the head by means of four cap screws which are turned “in”, or clockwise, to remove the tube. “Shelby” samplers are furnished complete with ball valve for positive vacuum control. This sampler should be forced down under steady pressure. Standard tube length is 2′6″ (762 mm). In patent application no.PCT/F193/00512 (WO 94/12760) the invention relates to a drilling apparatus including a drilling device that is intended to be fed into a hole to be drilled and which is preferably extendable in the longitudinal direction. The drilling device comprises a casing part essentially inside of which there is at least during a drilling situation a drilling unit in the drilling head of which there are at least a first drilling means for drilling a center hole and a second drilling means for reaming the center hole for the casing part as well as a flushing means for removal of the drilling waste. At least during the drilling situation the rotational movement around the longitudinal axis and the impact movement in the longitudinal direction of the first drilling means is transmitted by a counterpart assembly to the second drilling means that is drivingly connected to the first drilling means essentially at the drilling head of the drilling unit, wherein the second drilling means is arranged to rotate in connection with the head of the casing part centrically around the longitudinal axis by a coupling assembly. The first drilling means is arranged detachable from the second drilling means for removing the first drilling means from the prepared hole, while at least the second drilling means is left in the bottom of the hole. For example Patent Publications GB-959955 and GB1068638 disclose drilling arrangements such as the above. The solutions described in both mentioned publications comprise inner drilling means, in other words the center drill for drilling the centerhole and outer drilling means that is symmetrical in relation to the longitudinal axis of the drill and the leaving of which in the hole together with the casing part after the drilling situation is made possible. In such an arrangement, thanks to the centrical rotation movement of the outer drilling means or in other words the reaming drill, the risk of breakage of the drilling arrangement is rather small, especially compared with currently widely used drilling arrangements having eccentric reaming drills. The contact surface of the reaming drill according to the solution presented in the Patent Publication GB959955 touches the head of the casing part from the inside. In this case the effective diameter of the center drill is reduced also by the twist locking and impact surface assemblies between the center drill and the reaming drill. The mentioned publication presents two differing solutions, wherein as the twist locking assembly in the first solution a shape locking has been applied between the drilling means and in the other one a bayonet coupling between the same. Accordingly, the impact surface assembly comprises a recess-projection assembly between the reaming drill and the center drill that is situated in the front edge of the said twist locking assembly. In a solution described above, the casing part has to be fed into the hole to be drilled by influence of the center drill, wherein the feeding movement is transmitted by means of the counterpart assembly through the reaming drill, in which case the casing part follows the reaming drill. Thus it is practically possible that the impact movement of the center drill is transmitted at least partially also directly to the casing part. The Patent Publication GB-1068638 discloses a solution in which the reaming drill is placed end to end with 35 the head of the casing part. In this case there is an internal socket fixed in the reaming drill, which is placed in contact with the inner surface of the head the casing part. In the head of the casing part and in the socket there is a recess-projection assembly, by influence of which the socket remains in place in the longitudinal direction, however allowing rotation of the socket in relation to the casing part. In the solution above there has also been applied an additional block in connection with the arm of the center drill, which couples the rotational movement, feeding movement and impact movement of the center drill to the reaming drill by influence of the socket. It is common to solutions according to those above, that the effective diameter of the center drill is relatively small, that is about 50% of the inner diameter of the casing part. Naturally this is why it is necessary to apply excessively massive drilling rods, which naturally raises the manufacturing costs of the drilling arrangement explained above. Additionally the massiveness of the constructions is also a reason why the handling of the parts of the drilling arrangement is difficult, besides the usage of which demands high capacity. That is why the solutions of above explained types have currently not been used too much in practice, though a centrically rotating reaming drill has many significant advantages compared especially with so called eccentric reaming drills. Furthermore, existing solid and liquid manure spreaders are not well adapted for surface spreading or direct subsurface injection of semi-liquid dairy cattle manure. By taking into account the characteristics of this type of manure, a machine for either spreading or injecting semi-liquid manure was designed and constructed. Its manure handling system consisted of a tiltable tank connected to a vibrating distribution manifold that directed the manure to the spreading or injection devices. Manure was fed to the injectors by gravity via 152 mm (6 in.) diameter hoses. The 305 mm (12 in.) wide injectors were operated at depths not exceeding 203 mm (8 in.) in order to reduce draft requirements. Results from preliminary field testing of the prototype are reported along with the design modifications that were recommended following these tests. The present invention doesn't have to consolidate the samples and can remove only the specific area required for sampling. Consolidated samples are samples taken from sampling tools e.g. Direct push system and some auger type tools. These sampling tools start taking in the soil or product matter from entry and upon reaching the sampling area, the tool is filled with a lot of unwanted matter which mixes with the sample. It is an important object of the present invention, to achieve a decisive improvement in the problems presented above and thus to raise substantially the level of knowledge in the field in keeping with the state of the art. It is a further object of the present invention, to provide a reaming device in which there is no binding or sticking of the tool during operation. Yet another object of the present invention is to provide a reaming device which can rotate and change position or rotational, direction within the primary screw's bore. Still an additional object of the present invention is to provide a multifunctional screw drill and reaming device, in which both primary and secondary screws can be coupled and rotate as one unit. Furthermore an additional object of the present invention, is to provide a multifunctional screw drill and reaming device, in which both primary and secondary screws may be hydraulically, pneumatically, mechanically, electrically, or manually driven. Additional objects and advantages of the present invention will become apparent, as the following detailed description of the preferred embodiment is read in conjunction with the drawings and the Claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts an exploded isometric view of the present invention. FIG. 2 is a frontal perspective view of the present invention. FIG. 3 is frontal view showing the said invention penetrating the subject matter while no matter enters the primary bore (No. 17 ). FIGS. 4 & 5 present a frontal view of the present invention boring vertically or horizontally into the subject matter 2 nd procedure. FIG. 6 is a frontal view depicting removal of a disturbed sample-1 st Procedure. FIGS. 7 & 8 show a frontal view demonstrating removal of a disturbed sample-(2nd procedure: Part 1). FIGS. 9 & 10 show a frontal view depicting removal of a disturbed sample-(2 nd procedure: Part 2). FIGS. 11 & 12 : demonstrate removal of an undisturbed sample-(3rd procedure). FIG. 13 is an overhead perspective view of the present invention. FIG. 14 is a side perspective view of the secondary drive shaft in position No. 6 , boring vertically or horizontally into the subject matter (1st procedure). FIG. 15 is a side perspective view of the secondary drive shaft in position No. 7 , removing a disturbed sample (2 nd procedure. Part 1). FIG. 16 is a side perspective view of the secondary drive shaft in position No. 8 , removing an undisturbed sample (3 rd procedure) FIG. 17 is an isometric view of adjuster No. 22 as adjustment No. 23 moves the adjusting pin (No. 30 ) away from the secondary drive shaft No. 5 , giving the secondary drive shaft the required clearance to move to its three positions (Nos. 6 , 7 & 8 ). FIG. 18 : is an isometric view of adjuster No. 22 as adjustment No. 24 moves the adjusting pin (No. 30 ) towards the secondary drive shaft (No. 5 ) allowing the secondary drive shaft to rotate along any of its rotating grooves (Nos. 6 , 7 & 8 ). FIG. 19 : is an isometric view of adjuster (No. 22 ) as adjustment (No. 25 ) moves the adjusting pin (No. 30 ) further towards the secondary drive shaft (No. 5 ) allowing the secondary drive shaft to couple with the Primary drive shaft (No. 19 ) and rotate as one unit in any of its locating slots (Nos. 9 , 10 & 11 ). FIG. 20 shows a frontal view depicting removal of a gas sample and vapour extraction (4 th procedure). FIG. 21 is a frontal view demonstrating the present invention injecting a gas. FIG. 22 is a frontal perspective view of the present invention in operation in the process of injecting a substance. FIG. 23 shows the loading of the present invention (2 nd procedure). FIG. 24 : is a frontal perspective view showing the present invention fully loaded and boring through the subject matter for injection. FIG. 25 : is a frontal perspective view depicting the present invention removing a disturbed sample (1 st Procedure). FIG. 26 : is a frontal perspective view showing the loading of the present invention (1 st procedure). FIG. 27 depicts a cutaway frontal perspective view of a modified primary screw with drilled holes (No. 33 ) for gas extraction or venting (4 th procedure) after boring into the subject matter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is intended to create an aperture in a given location in the soil and is extendable in the longitudinal or latitudinal direction. All rotation mention is referred to FIG. 13 the overhead perspective view of the present invention. The present invention consists of a primary forward screw drill (No. 17 ), a secondary forward screw drill (No. 1 ) and reverse (No. 2 ) screw drill, said aforementioned screw drills being independently driven. Dependent upon the operation, the secondary screws (Nos. 1 & 2 ) can rotate and change position or rotational direction within the primary screw's bore (No. 17 ), or both primary and secondary screws can be coupled and rotate as one unit. The primary drive shaft (No. 19 ) connects and drives the primary forward screw drill (No. 17 ) and incorporates drive handles (No. 21 ), hose coupling (No. 27 ) and an adjuster (No. 22 ) (FIGS. 1 , 17 , 18 & 19 ) with three adjustments(Nos. 23 , 24 & 25 ). Adjustment No. 23 ( FIG. 17 ) allows the secondary drive shaft (No. 5 ) to move from one position to another (Nos. 6 , 7 & 8 ). Adjustment No. 24 ( FIG. 18 ) allows the secondary drive (No. 5 ) to rotate in any one of its positioning grooves (Nos. 6 , 7 & 8 ). Adjustment No. 25 ( FIG. 19 ) Allows the secondary drive shaft (No. 5 ) to couple with the primary drive shaft (No. 19 ) and rotate as one unit in any of its locating slots(Nos. 9 , 10 & 11 ). In a clockwise rotation ( FIG. 13 ), the primary screw drill bit (No. 17 ) penetrates, the primary screw executes the majority of penetration and in operation, removal of all unwanted material passes along its outer diameter screw, no unwanted material passes through the primary bore, hence there is no binding or sticking of the tool during operation. In an anticlockwise rotation ( FIG. 13 ), the primary forward screw (No. 17 ) will exit the targeted sampling area The secondary screw drills are housed within the primary screw drill's bore while the secondary drive shaft (No. 5 ) with drive handle (No. 13 ) and locking clips (No. 14 ) keep the drive handle in position, connects and drives the secondary forward (No. 1 ) and reverse (No. 2 ) screws, the secondary drive shaft (No. 5 ) has 3 locating grooves( Nos. 6 , 7 & 8 ) and 3 locating slots (Nos. 9 , 10 , & 11 ). The positioning grooves (Nos. 6 , 7 & 8 ) allow the secondary forward (No. 1 ) and reverse (No. 2 ) screws to rotate, in 3 different positions within the primary screw's bore ( FIGS. 2 , 3 , 6 , 7 , 8 , 14 , 15 , 16 , 20 , 21 , 22 , 23 , 25 , 26 & 27 ). The positioning slots (No. 9 , 10 & 11 ) couple the primary (No. 17 ) and secondary forward (No. 1 ) and reverse (No. 2 ) screws in 3 different positions within the primary screw's bore ( FIGS. 4 , 5 , 9 , 10 , 11 , 12 & 24 ). The secondary forward (No. 1 ) and reverse (No. 2 ) screws are comprised of two screws on one shaft. The first secondary screw assists the primary screw in penetrating and penetrates in a clockwise rotation. Dependent upon the subject matter for penetration, the forward screw (No. 1 ) can be replaced with different cutting tips. The secondary screw (No. 2 ) maintains a clear bore within the primary screw, until the boring, vertical or horizontal is completed. The reverse or secondary screw (No. 2 ) expels matter in a clockwise rotation. Rotating both screws in the same or opposite direction, the primary screw entering or exiting and the secondary screw pushing or pulling can only be accomplished by screw design. Sections of primary and secondary parts may be added for achieving greater depth penetration. Consisting of a primary screw and secondary screws, both sets of screws being independently driven, hydraulically, pneumatically, mechanically, electrically or manually and comprising: (1) A primary drive shaft which connects and drives a primary forward screw drill, incorporates drive handles, hose coupling and an adjuster with 3 adjustments. (2) A secondary drive shaft with 3 locating grooves and 3 positioning slots, connects and drives. (3) A secondary reverse screw with female and male splines, a secondary forward screw with male splines, locating pins and locking clips to couple with male and female splines. (4) A secondary drive handle and locking clips to keep said drive handle in position. The said invention can be used for Boring. Sampling and extracting. Injecting. The present invention can retrieve an undisturbed or disturbed sample, at any given depth, without any cross contamination and retain the integrity of each sample. In clockwise rotation—The tool enters the subject matter, the inner bore of the primary screw which is used to hold the sample on the secondary reverse screw, is always clear. This happens because the reverse screw expels in a clockwise direction, keeping the primary sampling bore clear of any matter. While the present invention is moving from depth to depth, no matter enters the sampling bore and therefore there is no cross contamination. The present invention may be cleaned after taking of each sample, flushing with steam and hot water through hose coupling (No. 27 ). To remove a disturbed sample at any given depth and remove that area only required for sampling is possible by changing rotation or position of the secondary forward and reverse screw, which is housed within the primary screw's bore, at the depth required to remove the sample. Removing an undisturbed sample may be done by changing the position of the secondary forward (No. 1 ) and reverse screw (No. 2 ) which is housed within the primary screw's bore (No. 17 ), at the depth required to remove the sample while the present invention is in operation, and will only remove that area needed for sampling. At the required sampling depth, rotation of both screws are stopped, the secondary screws (Nos. 1 & No. 2 ) are pushed up the primary bore leaving the required clear bore for the undisturbed sample. The primary screw is then rotated in a clockwise direction moving further into the subject matter, the sample is then compacted into the free bore within the primary screw, after the sampling distance has been completed rotation of the primary screw is stopped. The primary screw is then rotated in an anticlockwise direction for removal. The present invention is held over a collecting bin, the samples which were compacted into the primary screw's free bore (No. 17 ), within the primary bore there is a removable cylinder (No. 15 ) with the compacted sample, the cylinder is removed with the sample. This present invention can also be used as a medium for the extraction of soil vapour for testing or venting by connecting a vacuum pump to the top of the tool. Extraction takes place through the primary bore. When a larger soil area needs gas extraction or venting, a modified primary screw with drilled holes can be used ( FIG. 27 ), (No. 33 ). Extraction can now take place at the extraction point and along the drilled holes on the primary screw. This is possible because the inner bore of the present invention is always clear and there is no clogging of sampling point while in operation. Due to the design of the reverse screw, which is part 2 of the secondary screw, clockwise rotation expels any matter that may attempt to enter the primary bore, therefore, maintaining a clear primary bore. The reverse screw (No. 2 ) is housed in the primary screw's bore exposing approximately 3″ to 4″ ensuring no matter enters the primary bore. The present invention can move from depth to depth while gas sampling is being done and this sampling can be done at any given depth as follows: 1. Clockwise rotation A) Maintains a clear bore within the primary screw. B) The secondary reverse screw (No. 2 ) expels in a clockwise rotation. C) To inject at the appropriate depth. 2. Anticlockwise rotation A) To retrieve any sample. B) To load or fill the injector. The secondary reverse screw (No. 2 ) when coupled with the primary screw (No. 17 ), and used as an injector will hold the subject matter for injection, while the present invention is in operation and release the matter at the appropriate depth. Injecting any type of gas or liquid—a high pressure hose with the product to be injected is connected to the top of the primary bore, the injection tool injects from within the primary bore to the base of the present invention. Injection of gas or liquid may be needed in a larger area, not only at the injection point. A modified primary screw with drilled holes can be used to inject. Injection takes place at the injection point and along the drilled holes of the primary screw. Having a high pressure hose connected to the present invention is mainly used for gases. Liquids can be used with a high pressure hose or gravity fed. The secondary screws can be rotated in a clockwise direction to maintain a clear bore. Boring: Together the action is the boring and removal of debris, to eventually reveal a tunnel, no material is transferred through the primary bore, while boring is in operation. The primary screw remains at the desired horizontal distance. The secondary screw will be removed leaving a clear bore. The primary screw's bore can be used as a pipeline under a roadway, pass, or through a mountain. This pipeline can be used for almost any type of liquid, gas, electrical cables etc. This pipeline application can be used for drainage purposes. The main advantage which the present invention has over the prior art is, it does not allow any debris to pass through the primary bore like the existing tools, but instead allows the debris to pass at the outer primary screw. The primary screw executes the majority of penetration and while penetrating, removal of all unwanted material passes on its outer diameter screw, no unwanted material passes through the primary bore, hence there is no binding or sticking of the said invention during operation and simultaneously, the secondary forward screw No. 1 and reverse screw No. 2 are being rotated in a clockwise direction within the primary screw's bore. Boring vertical or horizontal 1 st procedure with secondary drive shaft No. 5 rotating in position No. 6 and the primary drive shaft adjuster No. 22 is set to adjustment No. 24 . ( FIG. 18 ) when adjuster No. 22 is set to adjustment No. 24 the secondary drive shaft can rotate within the primary (No. 17 ) screw's bore ( FIG. 18 ). The secondary forward screw and secondary reverse screw are made up of two screws on one shaft and with the secondary drive shaft (No. 5 ) rotating in position No. 6 , the function of the secondary screws are as follows ( FIGS. 2 , 3 & 14 ):— (1) The secondary screw assists the primary screw in penetrating any subject matter in a clockwise direction. (2) The secondary reverse screw maintains a clear bore within the primary screw, at all times and keeps pushing the material forward, feeding the primary screw, allowing material to stay at the front of the primary screw in order to move to the surface, or up or along the primary screw, until the vertical or horizontal boring is completed. The reverse screw expels in a clockwise direction. At this point in operation the secondary forward screw is exposed to the subject matter and the majority of the secondary reverse screw is housed in the primary screw's bore exposing part of the secondary reverse screw, ensuring that the intended subject matter of attention doesn't enter the primary bore. After boring has been completed, rotations of both primary and secondary screws are stopped and the following procedures for sampling, extracting and injecting are executed. The primary screw is rotated anticlockwise to remove it from the subject matter, or the primary screw remains at the desired location and the secondary screws are removed leaving a clear primary bore. Boring vertical or horizontal 2nd procedure, the said invention consists of a primary screw (No. 17 ) and secondary screws (Nos. 1 & 2 ), the secondary screws are housed within the primary screw's bore, the secondary screws can rotate independently from the primary screw, but this procedure locks up both screws and as they are coupled by adjuster, both primary and secondary screws rotate as one ( FIGS. 4 , & 5 ). Secondary drive shaft (No. 5 ) in position (No. 6 ) and the primary drive shaft adjuster (No. 22 ) are set to adjustment (No. 25 .) ( FIG. 19 ) and when adjuster No. 22 is set to adjustment No. 25 the secondary shaft cannot rotate within the primary bore, both primary and secondary screws are coupled as one ( FIG. 19 ). Clockwise rotation FIG. 4 , & FIG. 5 Primary screw (No. 17 ) penetrating and the secondary screws No. 1 & 2 rotate together with the primary screw No. 17 (not within). The secondary forward No. 1 and reverse No. 2 screws are made up of two screws on one shaft. (1) The secondary forward screw No. 1 assists the primary screw in penetrating. (2) The secondary reverse screw No. 2 maintains a clear bore within the primary screw, at all times and keeps pushing the material forward feeding the primary screw, allowing material to stay at the front of the primary screw in order to move to the surface, or up or along the primary screw, until the vertical or horizontal boring is complete, the reverse screw No. 2 expels in a clockwise direction. At this point in operation the secondary forward screw is exposed to the subject matter and the secondary reverse screw is housed in the primary screw's bore, exposing part of the secondary reverse screw, ensuring that the intended subject matter doesn't enter the primary bore. After boring has been completed, rotations of both primary and secondary screws are stopped and the following procedures for sampling, extracting and injecting can now be executed. The primary screw is rotated anticlockwise to remove the present invention from the subject matter, or the primary screw remains at the desired location and the secondary screws are removed leaving a clear primary bore. The present invention can remove (1) A disturbed sample of the subject matter (2) An undisturbed sample of the subject matter (3) A Gas sample and extract vapours at any given depth without dismantling the tool. This is possible by changing rotational direction or position of the secondary forward and reverse screws, at the depth required to remove the sample. Removing a disturbed sample 1st procedure. At the targeted sampling depth, the secondary drive shaft rotating in position No. 6 and the primary drive shaft adjuster No. 22 set to No. 24 . ( FIG. 18 ). Note—when adjuster No. 22 is set to adjustment No. 24 the secondary drive shaft can rotate within the primary screw's bore. At the targeted sampling depth, Note—The primary screw No. 17 bore is clear of any product, due to the design of the secondary reverse screw No. 2 . The secondary screws Nos. 1 & 2 are then rotated in an anticlockwise direction accompanied by the clockwise rotation of the primary screw No. 17 through the targeted sampling area FIG. 6 . This anticlockwise rotation of the secondary screws results in transfer of the desired sample into the primary screw bore. This is possible on the secondary reverse screw No. 2 . Note—Clockwise rotation of the secondary reverse screw No. 2 expels unwanted matter and in an anticlockwise rotation the secondary reverse screw No. 2 will take in the desired subject matter into the primary bore No. 17 . The rotation of the secondary screws is stopped. The primary screw No. 17 is then rotated in an anticlockwise direction for removal of the present invention. The said Invention is held over a collecting bin accompanied by the clockwise rotation of the secondary screws No 1 & 2 . This expels the desired sample and reveals it for observation and testing. Removing a disturbed sample 2 nd procedure. Part 1. The primary screw No. 17 bore remains clear of any matter, due to the design of the secondary reverse screw No. 2 . The secondary forward screw No. 1 is immersed in the subject matter but it cannot contain or retain any matter. Matter was moving through the secondary forward screw No. 1 from entry and removal of all unwanted material was being picked up by the primary's No. 17 outer diameter screw. At the targeted sampling depth, the secondary drive shaft No. 5 is moved to position No. 7 relocating the secondary screws ensuring that the secondary reverse screw No. 2 is not exposed and the majority of the secondary forward screw No. 1 is concealed in the primary screw's bore No. 17 exposing part of the secondary forward screw No. 1 , to assist the primary screw in penetrating and taking in the sample, when the primary drive shaft adjuster No. 22 is set to adjustment No. 24 the secondary drive shaft can rotate within the primary screw's bore No. 17 ( FIG. 18 ). The clockwise rotation of the primary forward screw No. 17 together with the clockwise rotation of the forward No. 1 and reverse No. 2 screws. Through the targeted sampling area and the position of the secondary forward screw No. 1 in the primary bore No. 17 will result in the transfer of the sample into the Primary bore 17 . The rotation of the secondary forward screw No. 1 is then stopped. The primary screw No. 17 is then rotated in an anticlockwise direction for removal of the present invention. The said invention is held over a collecting bin. The secondary screws No. 1 & 2 can be rotated in an anticlockwise direction or pushed back down to locating groove No. 6 FIG. 2 , this reveals the desired sample for observation and testing. Removing a disturbed sample—2 nd Procedure. Part 2 At the targeted sampling depth, the secondary drive shaft No. 5 is moved to position No. 7 relocating the secondary screws ensuring that the secondary reverse screw No. 2 is not exposed and the majority of the secondary forward screw No. 1 is concealed in the primary bore No. 17 , exposing part of the secondary forward screw No. 1 , to assist the Primary screw in penetrating and taking in the sample, when the primary drive shaft adjuster No. 22 ( FIG. 19 ) is set to adjustment No. 25 the secondary drive shaft No. 5 cannot rotate within the primary drive No. 19 . Both Primary forward screw No. 17 and Secondary forward No. 1 and reverse No. 2 screws are coupled and rotate clockwise as one unit through the targeted sampling area and the position of the secondary forward screw No. 1 in the primary bore No. 17 will result in the transfer of the sample into the primary bore No. 17 . The primary screw No. 17 is then rotated in an anticlockwise direction for removal of the said Invention. The Invention is held over a collecting bin. The secondary screws No. 1 & 2 can be rotated in an anticlockwise direction or pushed back down to its original position ( FIG. 2 ), this reveals the desired sample for observation and testing Removing an Undisturbed Sample At the targeted sampling depth, the primary screw's bore is clear of any product, due to the design of the secondary reverse screw No. 2 . At the targeted sampling depth, rotation of both primary and secondary screws is stopped ( FIGS. 11 & 12 ). The secondary drive shaft (No. 5 ) is in position (No. 8 ) and the primary drive shaft adjuster (No. 22 ) is set (to No. 25 ) relocating the secondary screws in the primary bore (No. 17 ), leaving the required clear bore for the undisturbed sample. The primary screw is then rotated clockwise, moving the tool further into the intended subject matter of attention, the sample is then compacted into the free bore within the primary screw, after the targeted sampling distance has been completed rotation of the primary screw is stopped. The primary screw is then rotated in an anticlockwise direction for removal of the said invention. The invention is held over a collecting bin, the samples which were compacted into the primary screw's free bore (No. 17 ), within the primary bore there is a removable cylinder (No. 15 ) with the compacted sample, the cylinder is removed with the sample. The present invention can also be used as a medium for the extraction of a Gas and soil vapour for testing or venting by connecting a hose (No. 31 ) to hose coupling (No. 27 ) then to a vacuum pump (No. 32 ). The secondary drive shaft rotating in position (No. 6 ) and the primary drive shaft adjuster (No. 22 ) set to adjustment (No. 24 ) then the secondary drive shaft can rotate within the primary screw's bore at the targeted sampling area, while the primary screw bore is kept clear of any matter, due to the design of the secondary reverse screw (No. 2 ). Extraction takes place through the primary bore. When a larger soil area needs gas extraction or venting, a modified primary screw with drilled holes (No. 33 ) can be used ( FIG. 27 ). Extraction can now take place at the extraction point and along the drilled holes on the primary screws; the secondary screws (Nos. 1 & 2 ) can be rotated in a clockwise rotation to maintain a clear primary screw bore. This process can be repeated at different depths, allowing multiple extractions on one entry of the said invention into the subject matter. The present invention may be loaded after entry and only at the targeted depth, the secondary drive shaft (No. 5 ) in position No. 6 , with the primary drive shaft adjuster No. 22 ( FIG. 18 ) set to adjustment No. 24 when adjuster No. 22 is set to adjustment No. 24 , then the secondary drive shaft (No. 5 ) can rotate within the primary screw's bore No. 17 . The secondary forward screw (No. 1 ) and secondary reverse screw (No. 2 ) are made up of two screws on one shaft with the secondary drive shaft(No. 5 ) rotating in position No. 6 , the function of the secondary screws are as follows: (1) The secondary forward screw No. 1 assists the primary screw No. 17 in penetrating clockwise. (2) The secondary reverse screw No. 2 maintains a clear bore within the primary screw and injects or expels, in a clock-wise rotation. For injecting subject matter: ( FIGS. 1 , 18 & 22 ) at the targeted depth the primary screw (No. 17 ), the secondary forward (No. 1 ) and reverse (No. 2 ) screws are stopped. A hose (No. 31 ) from a source containing solids, granules, liquids, or a mixture of solids and liquids can be connected to the top of the primary drive shaft (No. 19 ), through the fitting (No. 27 ). The secondary screws (Nos. 1 & 2 ) are rotated in a clockwise direction moving and injecting the mixture into the target area. This is possible due to the design of the secondary reverse screw (No. 2 ). This process can be repeated at different depths, allowing multiple injections on one entry of the said invention into the subject matter. For injecting a gas, ( FIGS. 1 , 18 & 21 ) at the targeted depth the primary screw (No. 17 ), the secondary forward (No. 1 ) and reverse (No. 2 )screws are stopped, a high pressure gas is delivered from a pump (No. 32 ) through a hose (No. 31 ) to be injected and which is connected to the hose coupling (No. 27 ) on top of the primary drive shaft (No. 19 ). The gas is then injected in the appropriate area, the secondary screws (Nos. 1 & 2 ) are rotated clockwise to maintain a clear bore. This process can be repeated at different depths, allowing multiple injections on a single entry of the said invention into the area of the subject matter. For loading the said invention 1 st procedure, ( FIGS. 1 , 18 & 26 ) a container or holding bin is filled with matter. The injector FIG. 26 of the present invention enters the holding bin in a vertical position. The primary screw (No. 17 ) and secondary screws (Nos. 1 & 2 ) can rotate independently of each other. The secondary drive shaft (No. 5 ) in position No. 6 , with the primary drive shaft adjuster (No. 22 ) set to adjustment No. 24 , the secondary shaft can now rotate within the primary screw's bore. With the clockwise rotation of the primary screw, penetration occurs. The secondary screws Nos. 1 & 2 are then rotated in an anticlockwise direction accompanied by the clockwise rotation of the primary screw (No. 17 ) through the subject matter. This anticlockwise rotation of the secondary screws and the position of the secondary reverse screw No. 2 in the primary bore (No. 17 ) results in transfer of the desired matter into the primary bore as the rotation of the secondary screws are stopped, the primary screw is then rotated in an anticlockwise direction for detachment. At this point the product is filled in the secondary reverse screw No. 2 and the said invention is loaded and ready to release its matter at any depth. Loading of invention (2 nd Procedure). The present invention is void of any matter, and is placed in a horizontal position with the secondary drive shaft No. 5 on location No. 6 , with the primary drive shaft adjuster No. 22 ( FIG. 18 ) set to adjustment No. 24 Note when adjuster No. 22 is set to adjustment No. 24 the secondary drive shaft No. 5 can rotate within the primary screw's bore No. 17 . A hose from a source containing Solids, granules, liquids or a mixture of solids and liquids can be connected to the top of the primary drive shaft No. 19 , through hose coupling No. 27 . The position and the clockwise rotation of the secondary drive shaft No. 5 will fill the secondary reverse screw No. 2 in the primary bore No. 17 . Note. The said invention is loaded and ready to release its product at any depth. Injection—2nd Procedure. Entry of the loaded injector tool filled with Product to be injected into the intended subject matter of attention. FIG. 24 The present invention is loaded and ready to release a designated substance at any depth, the secondary drive shaft No. 5 on location, No. 6 with the primary drive shaft adjuster No. 22 set to No. 25 . Note—when adjuster No. 22 is set to adjustment No. 25 . FIG. 19 . The secondary drive shaft can not rotate within the primary screw's bore, both primary and secondary screws are coupled together and rotate as one unit. The secondary forward screw No. 1 assists the primary screw No. 17 in penetrating the desired subject matter in a clockwise rotation. The secondary reverse screw No. 2 is to hold the product while the present invention is in operation (this is possible when both primary and secondary screws are locked or coupled together and rotate as one unit) and release it at the appropriate depth. At the targeted releasing depth both screws are uncoupled by adjuster No. 22 set to adjustment No. 24 , the screws can now rotate independently. The primary screw's rotation can be stopped and the secondary screws may then be rotated in a clockwise direction, within the primary bore releasing any matter while in a clockwise rotation the secondary reverse screw (No. 2 ) expels matter. After injection of the product into the subject matter, the rotation of the secondary screws is stopped. The primary screw is then rotated in an anticlockwise direction for removal of the present invention. Glossary:— 1. Secondary forward screw with male splines. 2. Secondary reverse screw with female and male splines. 3. Locating pin and locking clip to couple No. 1 & No. 2 via male and female splines. 4. Locating pin and locking clip to couple No. 2 & No. 5 via male and female splines. 5. Secondary drive shaft. 6. Shaft adjustment locating groove allows the Secondary drive shaft No. 5 to rotate within the Primary drive shaft 7. Shaft adjustment locating groove allows the Secondary drive shaft No. 5 to rotate within the Primary drive shaft. 8. Shaft adjustment locating groove allows the Secondary drive No. 5 shaft to rotate within the Primary drive shaft. 9. Locating slot to couple Primary No. 19 and Secondary No. 5 drives to rotate as one unit. 10. Locating slot to couple Primary No. 19 and Secondary No. 5 drives to rotate as one unit. 11. Locating slot to couple Primary No 19 and Secondary No. 5 drives to rotate as one unit. 12. Drilled hole to accommodate secondary drive handle No. 13 . 13. Secondary drive handle. 14. Locking clips to keep handle No. 13 in position. 15. Removable cylinder for undisturbed samples. 16. Locking screws to lock cylinder No. 15 in place. 17. Primary forward screw with female threaded bore to accommodate Primary drive shaft No. 19 . 18. Locking screws after connecting No. 17 and No. 19 . 19. Primary drive shaft with male threads to couple No. 17 . 20. Threaded bore to accommodate primary drive handles No. 21 . 21. Primary drive handles with threaded ends. 22. Adjuster. 23. This adjustment ( FIG. 17 ) allows the Secondary drive shaft to move to any of the following positions Nos. 6 , 7 & 8 . 24. This adjustment ( FIG. 18 ) allows the Secondary drive shaft to rotate to any of the following positions Nos. 6 , 7 & 8 . 25. This adjustment ( FIG. 19 ) allows the Secondary drive shaft to couple with the Primary drive shaft and rotate as one unit on any of the following No. 9 , 10 & 11 . 26. Threaded bore to accommodate adjuster No. 22 . 27. Hose coupling. 28. Hose coupling cover. 29. Adjusting pin Lever. ( FIG. 17 , FIG. 18 & FIG. 19 ) 30. Adjusting Pin.. ( FIG. 17 , FIG. 18 & FIG. 19 ) 31. Hose. ( FIG. 20 , FIG. 21 , FIG. 22 , FIG. 23 & FIG. 27 ) 32. Pump. ( FIG. 20 , FIG. 21 , FIG. 22 , FIG. 23 & FIG. 27 ) 33. Primary screw modified with drilled holes. ( FIG. 27 ) The aforementioned characteristic features of the present invention are set forth in the following claims as are given hereunder:

A multifunctional screw drill and reaming device, for the testing of the structure and composition of various soil types, as well as for sampling and boring, extracting and injecting of gases and various types of chemicals as well as liquids, slurry, granules and solids. Screws can be hydraulically, pneumatically, mechanically, electrically or manually driven. Dependent upon the operation, the secondary screws ( 2 ) can rotate and change position or rotational direction within the primary screw's bore ( 1 ), or both primary ( 1 ) and secondary screws ( 2 ) can be coupled and rotate as one unit.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is the US National Stage of International Application No. PCT/EP2008/060807, filed Aug. 18, 2008 and claims the benefit thereof. The International Application claims the benefits of U.S. provisional application No. 61/080,812 filed Jul. 15, 2008. All of the applications are incorporated by reference herein in their entirety. FIELD OF INVENTION [0002] The invention relates to a method for the assembly of a tower and to the tower. In a preferred embodiment the tower is used for a wind-turbine. BACKGROUND OF INVENTION [0003] Wind-turbines are conventionally mounted on top of steel-towers. The towers consist usually of a number of modules. [0004] As the price of steel is increasing more than the price of concrete it is advantageous to build wind-turbine-towers of concrete. [0005] For large experimental wind-turbines it is known to build and use concrete towers, which are built by using a so called “slip-form pouring method”. One example of this kind of tower was built 1977 for the Tvind-turbine in Denmark. [0006] This method has the disadvantage that the concrete has to be filled into a mould, which is located at the top of the tower. At the end of the construction procedure the concrete has to be filled into the mould at the final height of the tower. In dependency of this height the efforts for the fill-in increases. Furthermore personnel are required to fill-in in the concrete into the mould at this final-height, so their work is limited by the time of the day, by health-regulations and by safety-requirements due to the height. [0007] The WO 07025947 A1 discloses a method whereby a concrete tower is extruded vertically. This method has the disadvantage that it requires a very substantial technical arrangement, since high pressure is required for large-dimension components in order to push up the tower during casting. Large pressures at large diameters require very large technical arrangements. [0008] It is also known to build concrete towers by the use of pre-casted segments. Such segments show dimensions which might anticipate the transport of the segments via roads or bridges. So additional effort need to be done to solve the problems of transportation. [0009] It is known to build concrete towers by stacking of complete cylindrical elements. These elements are connected together by a number of post-tension cables. After the stacking of the elements a number of post-tension cables are inserted into channels in the tower walls. The channels transit the tower from the top to its bottom, while each post-tension cable is without discontinuation so the cable might reach a great effective length in dependency to the tower height. After cable insertion the channels are filled with a slurry material. [0010] This arrangement has the disadvantage that for a high tower a reliable injection of the slurry needs special precautions. [0011] Furthermore it may be difficult to insert the cables in the channels, particularly for a high tower. [0012] The U.S. Pat. No. 7,114,295 discloses an improved method to solve these problems. A funnel-shaped apparatus is used for guiding the tension-cables and for establishing a seal to produce a pressure-tight transition between two tower segments. However despite these arrangements the problem remains to insert the post-tension-cables and to inject slurry into the channel for greater tower heights. [0013] The U.S. Pat. No. 7,106,085 discloses a tower consisting of segments where no post-tension-cables are needed. This arrangement has the disadvantage that numerous mounting operations are required and that a high number of fasteners are needed. [0014] The US 2008 004 0983 A1 discloses a tower consisting of segments. The segments do not require tensioning-cables, because they are pre-assembled on ground. This arrangement has the disadvantage that numerous mounting operations are required and that a high number of fasteners are needed. [0015] The WO 08031912 A1 discloses a wind-turbine-tower, which is mounted with pre-fabricated elements. The tower has longitudinal ribs, which form longitudinal joints. These joints comprise metal elements and high resistance mortar. This leads to the disadvantage that numerous mounting operations are required and that a high number of fasteners are needed. Additionally high-strength mortar is needed. SUMMARY OF INVENTION [0016] It is the aim of the invention to provide an improved method for the assembly of a tower for a wind-turbine, and to provide an improved tower. [0017] This aim is solved by the features of the independent claims. [0018] Preferred embodiments are object of the dependant claims. [0019] According to the invention a number of pre-casted elements are stacked vertically to build the tower. Parts of the elements are forming the tower wall. Each element of the tower is fixed on its position and is connected with a tower foundation by a number of assigned post-tensioned cables, which are running inside the tower. [0020] The post-tensioned-cables of the elements are pulled through the tower without embedding in dedicated channels in the tower walls. The post-tensioned-cables are fixed at certain points with the tower wall via damper-means to prevent or to minimize their oscillation. [0021] The invention combines [0022] a stacking of pre-casted elements, [0023] the elements being fixed with post-tensioned cables that do not require to be inserted into special channels, and [0024] the post-tensioned cables being damped at certain points to minimize their vibrations. [0025] According to the invention a concrete tower is constructed by the stacking of cylindrical or tapered concrete pipes on top of each other. The pipes are joined to form a structural entity with post-tension cables which do not run inside cavities in the tower walls. The cables are hindered from oscillation through the application of suitable damper-means. [0026] In a preferred embodiment the concrete tower is built by a number of cylindrical or tapered pre-cast elements as modules, each forming a complete annular element. [0027] Some or all of these elements are fitted with structural elements that support dampers for attachment to the post-tensioning cables. [0028] The tower is constructed by a stacking of the pre-cast modules on top of each other, until the complete tower is formed. After this stacking the post-tensioning cables, are fitted and tensioned. During or after the cable installation suitable damper means are attached to the cables in order to prevent oscillation. [0029] In a preferred embodiment one or more of the pre-casted elements or modules are casted on a planned site. A bottom module is cast directly on the foundation. Supplementary modules are cast adjacent to the turbine-location or in another suitable location on or near a wind-farm site. Other modules are supplied as precast or prefabricated elements, maybe from elsewhere. Such other modules may be made of concrete or steel. [0030] Modules which are cast on a site can preferably be made with a module height that does not exceed the height at which an ordinary portable concrete pump for common contracting purposes can reach. [0031] A module or element can be cast in a form or mould consisting of a bottom part, an inner part, an outer part and a top part. The top part and/or the bottom part are integrated in a preferred embodiment into either the outer part or into the inner part. For example the bottom part may be integrated with the inner part and the top part may be integrated with the outer part. [0032] Due to the effect of installed post-tensioning cables longitudinal reinforcement of individual modules may not be needed to carry tensile stresses. The longitudinal reinforcement may be limited to the amount needed for handling purposes. Circumferential and shear reinforcement may be limited to the amount needed to ensure integrity under load and to transfer shear forces and torque. [0033] In a preferred embodiment fibre-reinforced concrete is used, classical reinforcement with rebars is avoided. Fibers could be steel- or glass-fibers. [0034] When the stacking of the modules is completed a number of cables are pulled partly and/or completely through the completed tower. The cables are fixed at a first end, thereafter they are fixed at the other end and tensioned. [0035] The tensioning-cables are fitted with suitable damper means. The damper means may be tuned absorbers or dampers achieving their effect by viscous means. [0036] In a preferred embodiment the damping is obtained by connecting the cables at regular intervals to a tower wall with a bracket or similar structures. The joint between cable and bracket and/or bracket and tower is fitted with a viscous damping element, e.g. a rubber or a tar compound [0037] In a preferred embodiment the lowest tower module is cast directly onto a foundation-base-plate, so the preparation of a tower plinth is avoided. [0038] In another preferred embodiment the lowest tower module is cast directly on rocky ground and the foundation is limited to simple rock-anchors. BRIEF DESCRIPTION OF THE DRAWINGS [0039] The invention is shown in more detail by help of the following figures, where: [0040] FIG. 1 shows a wind-turbine using the tower according to the invention, [0041] FIG. 2 shows the concrete tower according to the invention, referring to FIG. 1 , [0042] FIG. 3 shows the tower according to the invention in more detail, referring to FIG. 2 , [0043] FIG. 4 shows a transversal section through the tower 3 , referring to FIG. 3 , [0044] FIG. 5 shows a longitudinal section through the concrete tower according to the invention. [0045] FIG. 6 shows a transversal section through the tower 3 , referring to FIG. 5 , [0046] FIG. 7 shows four variants of a joint to connect tower modules, and [0047] FIG. 8 shows further variants of the joint between adjacent tower modules and of cable arrangements. DETAILED DESCRIPTION OF INVENTION [0048] FIG. 1 shows a wind-turbine using the tower according to the invention. The wind-turbine comprises a rotor 1 , which is supported by a nacelle 2 . The nacelle 2 is mounted on a tower 3 , which is supported by a foundation 4 . [0049] FIG. 2 shows the concrete tower 3 according to the invention, referring to FIG. 1 . [0050] The concrete tower 3 is constructed with elements as modules 5 , which are stacked on top of each other. In a preferred embodiment a last module 6 , which is located on top of the tower 3 , is substantially shorter than its preceding module 5 . [0051] FIG. 3 shows the tower according to the invention in more detail, referring to FIG. 2 . [0052] In this embodiment each tower module 5 (except the tower module 6 on the top) shows a cable-supporting protrusion 7 at its top. [0053] On the right side of the tower 3 centerlines of post-tensioning cables 8 are shown. Some of them run through the entire length of the tower 3 , from the top module 6 down to the foundation 4 , crossing all the modules 5 . [0054] Other post-tensioning cables 8 transit only through a number of modules 5 , so they run from the top of a dedicated module 5 through all the modules 5 , which are located below the dedicated module 5 . [0055] In this figure the post-tensioning cables 8 are shown descending vertically. [0056] FIG. 4 shows a transversal section through the tower 3 , referring to FIG. 3 . [0057] In this example each of the tower modules 5 and 6 has four post-tensioning cables, which connects the modules 5 and 6 to the foundation 4 . [0058] The cables from the tower modules 5 , 6 are located in an offset-circumferentially manner, so they do not interfere with each other. [0059] A tower wall 9 encloses the cables. [0060] As the cables are descending vertically in this example, four cables 10 from the top module 6 are closest to a centre CT of the tower. [0061] Four cables 11 are assigned to a module 5 - 1 , while four cables 12 are assigned to a module 5 - 2 and four cables 13 are assigned to a module 5 - 3 , counted down from the top of the mast 3 to the foundation 4 . [0062] The cables 11 , 12 and 13 are located progressively closer to the tower wall 9 . [0063] FIG. 5 shows a longitudinal section through the concrete tower 3 according to the invention. [0064] Differing to FIG. 3 the post-tensioning cables 8 descend parallel to the tower wall 9 . [0065] FIG. 6 shows a transversal section through the tower 3 , referring to FIG. 5 . [0066] In this example each of the tower modules 5 and 6 show four post-tensioned cables, which connect the modules 5 and 6 to the foundation 4 . [0067] The cables from the tower modules are located in an offset-circumferentially-manner, so they do not interfere with each other. [0068] A tower wall 9 encloses the cables. Because the cables descend in parallel to the tower wall 9 , the four cables 10 from the top module 6 , the four cables 11 from a module 5 - 1 , the four cables 12 from a module 5 - 2 and the four cables from a module 5 - 3 show an equally spacing from the tower wall 9 . [0069] FIG. 7 shows four variants of a joint to connect the tower modules. [0070] Referring to FIG. 7A the tower module 5 - 1 has a cable-supporting protrusion 7 that either serves as anchor point for a post-tensioning cable 8 or that serves as support for the damping of a cable from a higher module—e.g. by a channel 14 that may be filled with a tar-based or a rubber-based compound once the cable 8 is already inserted. [0071] Referring to FIG. 7B adjacent modules 5 - 1 and 5 - 2 are centered using a finger- and groove-arrangement 15 . [0072] Referring to FIG. 7C adjacent modules 5 - 1 and 5 - 2 are centered using an overlap. [0073] Here the cable-supporting protrusion 7 is extended inwards to serve as a platform, only leaving a hole 16 for power cables, for a ladder or a lift. [0074] An upper module 5 - 1 has a recess 17 that centers the upper module 5 - 1 when it is mounted onto the lower module 5 - 2 . [0075] Referring to FIG. 7D adjacent modules 5 - 1 and 5 - 2 are centered using an overlap. [0076] Here the cable-supporting protrusion 7 is extended upwards to provide a centering recess 18 for an upper module 5 - 1 . The upper module 5 - 1 centers on this recess 18 when it is placed onto a lower module 5 - 2 . [0077] FIG. 8 shows further variants of the joint between adjacent tower modules and of cable arrangements. [0078] Referring to FIG. 8A the tower module 5 - 1 and 5 - 2 does not have a cable supporting protrusion as described above. [0079] Instead of this a centering piece 19 is placed between two adjacent modules 5 - 1 and 5 - 2 . The centering piece 19 has holes 14 , which are used for the cables 8 . [0080] Referring to FIG. 8B the centering piece 19 has only a small hole 20 for power cables, for a lift or ladder and thereby it is used as a platform. [0081] Referring to FIG. 8C an attachment of the post-tensioning cables 8 at a centering piece 19 is shown. [0082] The cable 8 projects through a hole 14 in the centering piece 19 . On top of a load distributing washer 20 or ring 20 the cable 8 is tensioned using a nut 21 . [0083] Referring to FIG. 8D a damping of a post-tensioning cable 8 attached at a higher level is shown. [0084] The cable 8 passes through a hole 14 in the centering piece 19 . [0085] Once the cable 8 is tensioned, a suitable damping compound 22 is applied to be filled into the hole 14 .

A number of pre-casted elements are stacked vertically to build the tower, while parts of the elements are forming the tower wall. Each element of the tower is fixed on its position and is connected with a tower foundation by a number of assigned post-tensioned cables. These cables are running inside the tower and they are pulled through the tower without embedding in dedicated channels. The post-tensioned-cables are fixed at certain points with the tower wall via damper-means to prevent their oscillation.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED DOCUMENTS The present patent application is a Continuation of patent application Ser. No. 11/421,589, filed on Jun. 1, 2006 now abandoned. The priority application is incorporated herein in its entirety by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is in the field of construction, pertaining more specifically to the art of framing in construction and methods and apparatus for securing and locking structural members into position, applicable in many areas, such as construction for sub flooring, ceiling, roof, and other framings requiring structural members, and for structures in furniture, containers, models, and temporary shelters, among many other uses. 2. Discussion of the State of the Art In the field of framing for construction joisting is regularly employed to form a load-bearing floor, roofing, or ceiling framework comprising of multiple structural members laid parallel to one another and fastened to common end plates or beams. A typical structural member defines the elongate member laid with other like members to form a sub-floor, roof, or a ceiling truss. In constructions of differing materials the structural members are laid somewhat uniformly in the arrangements or structures according to certain standards set for those types of constructions. A problem with standard joisting is that it is limited to simple or continuous spans with bearing-type connections and is particularly weak with respect to resisting force from certain directions variant from typical load-bearing (vertical) forces or dead weight. Depending on construction materials used in a particular project, there are various standard methods for securing structural members to each other and to end plates. Nails, screws, metal bracing, and other components may be used depending on specifications for the construction project. A problem with typical joisting and joisting with prefabricated truss works is that other than vertical load-bearing, there is no inherent structural integrity for resisting certain directional forces that can occur such as wind shear, earthquake, and other forces. Therefore, what is clearly needed is a structural member lock and positioning system that distributes load resistance to vertical members across the construction and adds structural strength to resist forces other than vertical load forces. SUMMARY OF THE INVENTION In an embodiment of the present invention a structural assembly is provided comprising a first set of first elongate structural members alternately spaced apart from a second set of second elongate structural members by locking blocks, the first set defining a first plane and the second set defining a second plane forming an intersection at an angle with the first plane, the structural members and locking blocks defining an assembly of adjoined blocks and structural members at the intersection, and a compressive mechanism spanning the assembly of adjoined blocks and structural members at the intersection. Compressing the adjoined blocks and structural members by the spanning compression mechanism locks the blocks and structural members together in a manner to resist applied forces. In one embodiment the compressive mechanism comprises a rod, wire or cable passing through aligned openings in the adjoining blocks and structural members at the intersection, and one or more elements applying tension to the rod, wire or cable. Also in one embodiment the structural members and the blocks have complementary shape such that adjoining blocks and structural members engage at a specific angle defined by the engagement shapes of the blocks. In some embodiments the structural members have an I-beam shape with a central planar member and wider rails at each end, the locking blocks have channels to engage the wider rails, with sets of channels on opposite sides to engage adjacent structural members, with the sets of channels oriented at an angle to one another, defining the angle of the planes at the intersection. Also in some embodiments there may be a third set of structural members defining a third plane parallel to the first plane and a fourth set of structural members defining a fourth plane parallel to the second plane, the first and second planes intersecting at a first intersection at ninety degrees, the second and third planes intersecting at a second intersection at ninety degrees, the third plane and the fourth plane intersecting at a third intersection at ninety degrees, and the fourth plane and the first plane intersecting at a fourth intersection at ninety degrees, the four planes defining a rectangular box. In some embodiments there panels fastened to the separate sets of structural members, providing a top, a floor, and two sides to the structural assembly. In another aspect of the invention a method for making a rigid structural assembly is provided, comprising the steps of (a) spacing apart a first and a second set of elongate structural members alternately with locking blocks such that the first set defines a first plane and the second set defines a second plane in an intersection at an angle with the first plane, the structural members and locking blocks defining an assembly of adjoined blocks and structural members at the intersection; and (b) compressing the adjoined structural members and inter-spaced locking blocks at the intersection with a spanning compression mechanism. In one embodiment of the method the compressive mechanism comprises a rod, wire or cable passing through aligned openings in the adjoining blocks and structural members at the intersection, and one or more elements applying tension to the rod, wire or cable. In another embodiment the structural members and the blocks have complementary shape such that adjoining blocks and structural members engage at a specific angle defined by the engagement shapes of the blocks. Also in some embodiments of the method the structural members may have an I-beam shape with a central planar member and wider rails at each end, the locking blocks have channels to engage the wider rails, with sets of channels on opposite sides to engage adjacent structural members, with the sets of channels oriented at an angle to one another, defining the angle of the planes at the intersection. In some embodiments there may be a third set of structural members defining a third plane parallel to the first plane and a fourth set of structural members defining a fourth plane parallel to the second plane, the first and second planes intersecting at a first intersection at ninety degrees, the second and third planes intersecting at a second intersection at ninety degrees, the third plane and the fourth plane intersecting at a third intersection at ninety degrees, and the fourth plane and the first plane intersecting at a fourth intersection at ninety degrees, the four planes defining a rectangular box. Also in some cases there are panels fastened to the separate sets of structural members, providing a top, a floor, and two sides to the structural assembly. BRIEF DESCRIPTION OF THE DRAWING FIGURES FIG. 1 is perspective view of a frame assembly according to an embodiment of the invention. FIG. 2 is a perspective view of the assembly of FIG. 1 flipped around to illustrate the inside construction of the assembly. FIG. 3 is a perspective view of the structural members of FIGS. 1 and 2 . FIG. 4 is a perspective view of the structural member lock of FIG. 1 according to an embodiment of the invention. FIG. 5 is a plan view of a structural member assembly according to an embodiment of the invention. FIG. 6 is a perspective view of a structural member assembly locked at an angle other than 90 degrees. FIG. 7 is a plan view of an angled structural member assembly according to an embodiment of the invention. FIG. 8A is a perspective view of a torsion locking block according to another embodiment of the present invention. FIG. 8B is a perspective view of a torsion locking block according to another embodiment of the present invention. FIG. 9 is an illustration of a basic box structure according to an embodiment of the invention. DETAILED DESCRIPTION FIG. 1 is perspective view of a frame assembly 100 according to an embodiment of the invention. Frame assembly 100 is a framing configuration in construction that provides a construction framing for floors, walls, and ceilings of a structure or building. Assembly 100 consists of multiple structural members 101 and 102 positioned and locked into place by multiple torsion locking blocks 103 placed between each of vertical structural members 101 and horizontal structural members 102 . In this example, structural members 101 and 102 are identical to one another in physical description and may be used as either vertical or horizontal members. Structural members 101 and 102 may be made of wood, steel, aluminum, or some other durable material suitable for building construction. Torsion locking blocks 103 may be made of wood, steel, aluminum, or some other durable material suitable for building construction. Structural members 101 and 102 have physical features that interface and engage with physical features on the joist-interfacing sides of torsion locking devices 103 in this configuration. In this example there are 4 vertical structural members 101 and 4 horizontal structural members 102 assembled with 7 torsion locking blocks 103 . This framing example may represent, for example, a junction of a sub floor and vertical wall framing of a building under construction. It will be appreciated by one with skill in the art of construction that the entire building frame is not represented in this example. In this case the structural members are secured at a right angle (90 degrees), common for floor-to-wall interfaces. The structural members are secured to the locking blocks at their ends in this example. In other construction configurations the angle may differ from 90 degrees and the structural members may intersect with torsion locking blocks at any intersection point placed along the length of those members. A compression system 105 is provided to compress the collective components of the assembly together in the geometric configuration shown. Compression system 105 comprises a solid and durable elongate bar or rod 107 that passes through openings located in structural members 101 and 102 and in torsion locking blocks 103 . System 105 may include compression washers and tensioning nuts applied to the ends of the assembly to secure and compress the assembly together. The elongate rod 107 used may be manufactured of steel or another solid and durable material capable of serving as a compression medium without failing under tensioning applied at the ends of the assembly. In alternative embodiments cable or wire may be used rather than a rod or bar, and various tensioning mechanisms may be used to compress the structural members and the locking blocks together. Assembly 100 is superior in strength to other construction geometries using structural members because the torsion locking blocks 103 together with the compression system 105 applied to secure the assembly provide transfer of shear, torsion, and moment forces laterally between adjacent structural members 101 and 102 in a direction substantially perpendicular to the direction of the structural members in the assembly. Assembly 100 includes multiple exterior and interior panels 104 that help to secure the structural members together with other structural members in the assembly. Panels 104 are attached in this example to the assembly at the outside and inside edges of the structural members. Panels 104 may be manufactured of plywood, metal sheeting, fiberglass sheeting, or other relatively stiff material. Panels 104 help to ensure transfer of shear and moment forces across the assembly, but are not essential in the broad aspects of this invention. Exterior panels 104 come together at the rear edge of the assembly and are fastened to the assembly with the aid of a blocking element 106 (interior blocking element visible). Blocking elements 106 are positioned both on the exterior and interior sides of the assembly and are connected between the structural members 101 and 102 , and torsion locking blocks 103 . Blocking elements 106 have fasteners that tie the components together when panels 104 are added to the assembly. Blocking elements 106 provide a continuous load path between the other elements of the assembly and further allow adjacent panels 104 to be connected or secured across their lateral intersection. Blocking elements 106 may be manufactured from wood, steel, aluminum, or some other solid and durable material capable of load transfer. FIG. 2 is a perspective view of the assembly of FIG. 1 rotated to illustrate the inside construction of the assembly in this example. In this view blocking elements 106 are visible in position between horizontal structural members 102 and vertical structural members 101 . Fasteners holding blocking elements in position and to panels 104 are not visible in this example but are assumed present. The construction and type of fasteners used will depend on the material selection of the components in the assembly. The exact method of fastening is not relevant to the invention. FIG. 3 is a perspective view of one each of structural members 101 and 102 of FIGS. 1 and 2 , shown isolated. Structural member 101 and structural member 102 are identical to each other in physical description in this embodiment, but may differ somewhat in other embodiments. In this example the shared physical features between structural members 101 and structural members 102 have the same element numbers and description. Each structural member 101 and 102 consists of substantially parallel rails 302 formed along longitudinal edges of the structural members. A thinner middle body 301 is disposed between rails 302 forming a complete structural member much in the manner of an I-beam. In a preferred embodiment, structural members 101 and 102 are contiguous parts formed of the same material. In some embodiments rails 302 may be separate components joined to middle body 301 to form a structural member that may function as a part formed of one material. In this example, rails 302 are rectangular in profile. The rectangular portion of each rail 302 on one side of body 301 is of a dimension that fits into channels provided on interfacing sides of the torsion locking blocks. The I-beam construction profile of structural members 101 and 102 provides sufficient transfer of load forces and is particularly suited for strength. Structural members 101 and 102 each have openings 303 in alignment with one another in appropriate configuration for assembly with the interspaced locking blocks. Openings 303 are sized to accept the tensioning bar or rod 107 . Structural members 101 and 102 have each have openings 303 at locations along each structural member where a torsion structural member lock may be placed, not necessarily just at the ends of the members. Further, structural members 101 and 102 may be of any required length for construction. The structural members may be assembled using a torsion structural locking block at any desired linear angle including 180 degrees. In one embodiment the angle of construction of the structural members is set by the construction of the torsion structural member locks. For example, a 90-degree angle would require a 90-degree torsion structural member lock. FIG. 4 is a perspective view of a torsion locking block 103 of FIG. 1 according to an embodiment of the invention. Torsion locking block 103 may be manufactured of steel, wood, fiberglass, or other construction materials. Locking block 103 in this example is quadrilateral in shape having 4 sides, a top surface and a bottom surface. Sides 402 and 404 are the sides that interface with structural members. Sides 406 and 405 do not interface with structural members. Opposing sides of structural member block 103 are substantially parallel to each other as are the top and bottom surfaces. In one embodiment torsion locking block 103 is of a solid construction. In another embodiment, locking block 103 may be manufactured of separate components that fit together to function as one piece. One or more openings 407 are provided at or around the approximate center of locking block 103 extending from side 402 through side 404 . Opening 407 is a through-bore and has a diameter sufficiently large for accepting the tensioning rod 107 , or whatever tensioning element is to be used. Torsion locking block 103 has a pair of channels 401 along opposing edges of side 402 . Channels 401 are identical to one another in depth and function to accept the rails provided on the structural members 101 and 102 . Channels 401 are substantially symmetrical and extend the length of side 402 in a horizontal direction for supporting one of horizontal structural members 102 described further above. The spacing between the opposing shelf walls is just small enough to accept the spacing between the inner opposing walls of the rails of a structural member. Channels 401 have a depth measured from surface 402 that is just large enough to enable the structural member body in between the rails to interface flush against surface 402 . The fit is tight enough so that there is very little or no movement in the angle of the assembly. On surface 404 there is a like pair of channels 403 provided in orientation rotated approximately 90 degrees from channels 403 to accept vertical structural members 101 described earlier. In this embodiment, torsion locking block 103 is a 90-degree block, meaning that adjacent structural members abutting the locking block are disposed linearly at a 90-degree angle such as where a floor meets a vertical wall. However, other torsion locking blocks may be provided of varying angles between 0 and 180 degrees. FIG. 5 is a plan view of a structural member assembly 500 according to an embodiment of the invention. Structural member assembly 500 includes 2 horizontal structural members 102 spaced evenly apart in assembly from a vertical structural member 101 by 2 torsion locking blocks 103 . In this example, the assembly is secured and compressed by compression system 105 , which includes in this instance a rod 502 passing through the assembly and held in place by tensioning nuts 501 at either end of the assembly. Applying tension to the assembly provides the compression needed to ensure transfer of lateral shear and moment forces through the assembly, equally distributing the load. FIG. 6 is a perspective view of a structural assembly 600 locked at an angle other than 90 degrees. Assembly 600 is implemented at an angle other than 90 degrees by using a torsion locking block 603 having channels orientated at an angle other than 90 degrees. In this case, a horizontal structural member 602 has a locking interface located approximately at a center point of the length of the member, rather than at one end of the member. Vertical structural member 601 may be identical to structural member 101 described earlier. However, in this embodiment, the ends of structural member 601 are angled according to the angle of block 603 , instead of being cut off at a 90 degree angle. In this case, the angle of construction (linear angle formed by assembled structural members) will be the same angle set by the structural member locking blocks used in the assembly. In this example, the frame construction may be that of an interior wall intersecting with a floor that rises at the particular angle set by the torsion locking blocks. Blocking devices 106 are shown in place for fastening to panel coverings described earlier. FIG. 7 is a view of a structural member assembly 700 also according to an embodiment of the invention, comprising structural members 701 forming a wall structure, locked along interface 704 to members 702 forming a canted roof, with an optional eave extension as shown in the drawing. Interface 705 is a roof peak with one side of the roof locked to the other side using locking blocks (in this case diamond shaped to match the intersecting shapes of the members) and compression along the peak ridge. In this manner locking blocks may be provided having the appropriate engagement and locking angles for different roof angles, and structural members may be trimmed for length and end shapes to suit. FIG. 8A is a perspective view of a torsion locking block 800 according to another embodiment of the present invention. Block 800 has a main body 801 and tongues 802 and 803 extending off of the main body of the block. Block 800 may be formed of a single piece of steel, wood, fiberglass, or some other durable construction material. In one embodiment, main body 801 and tongues 802 and 803 may be separate components joined together to function as one piece. In this embodiment block 800 is of a single contiguous construction. In this example, the sides of block 800 that interface with structural members are parallel to the end of each tongue 802 and 803 . That is to say the surfaces lie in the same plane. The back surfaces of tongues 802 and 803 are angled so that the tongues are thicker at the base of main body 801 and thinner at their open ends. Under compression in assembly, the framing may be further strengthened somewhat by the extra footprint provided by tongues 802 and 803 . The width dimension of tongues 802 and 803 is small enough to fit within the inside dimension between rails of the structural members so that the interfacing surface may be seated flush against the middle body of the structural members. A through opening 804 is provided in similar fashion as was described above for accepting a tensioning rod, cable or wire. FIG. 8B is a perspective view of a torsion locking block 805 according to yet another embodiment of the present invention. Block 805 has a main body 806 and includes tongues 807 and 808 that interface with structural members in similar fashion as tongues 802 and 803 . Tongues 807 and 808 may be contiguously formed with main body 806 or they may be separate components joined to main body 806 . In this variation, tongues 807 and 808 are of a uniform thickness from the open ends to main body 806 . It is noted herein that block 800 and block 805 may be interchangeable in the same framing assembly without departing from the spirit and scope of the present invention. For example, block 800 may be placed in the portion of the assembly that bears more vertical load while block 805 may be suitable for portions of the assembly where there is less vertical load. It will be apparent to one with skill in the art that locking blocks 800 and 805 may both be provided as blocks that present a construction angle that departs from 90 degrees, as has already been discussed above for block 103 . Moreover, the overall thickness of block 103 , block 800 or block 805 may be changed considerably so that structural members may be secured in the assembly having more or less separation, including structural members immediately adjacent or quite widely separated. FIG. 9 illustrates a basic box structure 900 using the framing methods and elements of the invention, which may resist loads from any direction and simultaneous loads from multiple directions. Structure 900 , including all of the components described and properly assembled and tensioned may require as few as 4 vertical supports 905 (three are visible in the perspective view) to the ground or to a supporting structure below. In this example, a simple rectangular structure 20 feet wide, 20 feet tall, and 40 feet long uses wooden I-structural members and the framing components described above for floors and roof members spaced at 16 inches on center, with the wall structural members made of the same or similar elements, shapes and spacing but offset from the floor structural members by approximately 8 inches center-to-center. The top and floor are connected to the walls of the structure using torsion locking blocks according to an embodiment of this invention with a steel tension rod, wire or cable passing through the assembly at the intersections 901 , 902 , 903 and 904 of horizontal and vertical planes, from one end of the structure to the other end of the structure (40 foot length), and with appropriate tension applied. The top, floor, and walls of the structure are covered by plywood panels in this example, fastened using wood screws or nails, and the blocking components previously described along all of the panel edges completing the structural framing and form. The construction once formed according to the methods and apparatus of the invention is open on each end, although non-load bearing walls may be added including windows, doors, and other openings according to normal construction guidelines and rules. Doors, windows and the like may also be implemented in the long sides of the structure. Structure 900 is a basic structure that may pre-fabricated and shipped to a building site, and used there as the basic unit for a home. Structure 900 may be placed on and secured to a foundation, or other simple supports as shown, and a roof and missing walls added by conventional structural techniques, providing a house much more resistant to natural forces than in the current art. In one embodiment of the present invention, the components used for the framing may be pre-manufactured and then assembled forming the assemblies during the framing process at a building site. In another embodiment, entire flooring systems, roof systems, ceiling systems and walls may be assembled to specification and then the assemblies may be positioned and further assembled at the corners to secure the complete structure similar in some aspects to assembling a panelized construction. In alternative embodiments similar pre-loaded and pre-fabricated structures according to embodiment of this invention may be provided in a variety of sizes and shapes for a wide variety of purposes, such as storage structures, temporary housing units and the like, and for almost any construction purpose. The methods and apparatus of the invention apply to wood construction and steel construction both residential and commercial. Lighter structures may be envisioned that may be fabricated of polymers, fiberglass, aluminum, and other materials depending on load requirements. There are many possibilities. Further it will be apparent to the skilled artisan that there may be many alterations made to the embodiments described as examples in this specification without departing from the spirit and scope of the invention. For example, structural members are shown in examples as I-beam shapes, and engaging geometry of locking blocks comprise edge channels in the blocks to engage the rails of the I-beam shapes. There are, however, a very wide variety of complementary engaging shapes that may be used, all of which are within the spirit and scope of the invention. There are similarly a wide variety of shapes and geometric variations that may be used beyond the simple example described herein. The apparatus and methods of the invention are useful for many sorts of construction where different surfaces may intersect. The invention for these and other reasons is limited only by the breadth of the following claims.

A structural assembly has a first set of first elongate structural members alternately spaced apart from a second set of second elongate structural members by locking blocks, the first set defining a first plane and the second set defining a second plane forming an intersection at an angle with the first plane, the structural members and locking blocks defining an assembly of adjoined blocks and structural members at the intersection, and a compressive mechanism spanning the assembly of adjoined blocks and structural members at the intersection. Compressing the adjoined blocks and structural members by the spanning compression mechanism locks the blocks and structural members together in a manner to resist applied forces.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION The invention relates to an arrangement of grinding modules with grinding tools in track grinders. Such arrangements are used in reprofiling the head of a track profile, in removal of short waves (groovings) as well as in truing long waves in a driving direction. Mostly grinding wheels are used as grinding tools. Track grinding machines are already known in which a surface pressure of a grinding module is increased or reduced, depending on whether the grinding module moves over a wave trough or over the top of a wave, so that any such waves are leveled, refer to DE-OS 2 037 461. Furthermore, track grinding machines with hydrostatic control are known which, irrespective of the rising of the line or the train resistance, keep to the rate of advance with high precision. A precise positioning of the grinding wheels is essential for the regeneration of the rails, refer to the grinding machine LRR 8-M of the Speno Company. This, however, is particularly problematic with small radii of curvature (<30 m) since there is a comparatively large radial departure of the grinding modules due to common wheel center distances, in particular when both rails are simultaneously ground. SUMMARY OF THE INVENTION It is an object of the present invention to provide an arrangement of grinding modules in a track grinding machine which permits to exactly involve a radial departure in narrow rail curvature radii (<15 m) without provoking reactive forces, and which allows reprofiling in a reproducible and simple way. The object is realized by the the present invention providing an arrangement of grinding modules with grinding tools in track grinders, characterized in that each grinding tool has five degrees of freedom of movement, whereby two linear movements are transverse to the rail to be ground, two linear movements are at least approximately vertically to the rail to be ground and one rotational movement is about an axis which is directed in parallel to the rail at the respective grinding site. Thereby it is of no concern whether or not the arrangement has to grind only one rail or to simultaneously grind both rails of a track. In the latter case the arrangement can be used with particular effectiveness. Furthermore, the number of grinding modules, which are comprised to a reprofiling unit in a frame, is insignificant, whereby the frame can be made, for example, of tubular steel. An advantageous arrangement according to the present invention is obtained when at least one grinding module is at least approximately vertically adjustably seated in a frame and at least approximately horizontally and adjustably seated on a mount via the frame. In the mount, there is provided a housing pivotally arranged about an axis, the axis is at least approximately parallel to a rail to be ground, and in the housing a grinding cylinder is at least approximately displaceable at right angles to the rail to be ground. Preferably a measuring wheel is provided for each grinding module and means for carrying out a relative movement between the grinding module and the measuring wheel. In this way it is possible to include a radial deviation for each grinding module, particularly in narrow curves. In order to have the measuring wheels always engage via their wheel flanges the rail to which they are associated, each measuring wheel is rotationally seated in a seating mount, which is adjustable, transversely to the rail to be worked on, along a guiding means on the frame, by aid of a servo-drive or a drive means and gearing, preferably a lever system. Preferably, horizontal transversal movement of the mount seated on the frame is carried out by way of a fluid transmission gear in dependence on the transversal movement of the measuring wheel. Thus it is possible to drive into three defined positions (driving the reprofiling unit into operation position, into positioning of the grinding modules, and in pressing the grinding modules to the rail) without the necessity of employing expensive sensing means for each position. Advantageously, the fluid transmission gear comprises a double cylinder with two opposing pistons in a cylinder chamber of the double cylinder. This design permits using the arrangement according to the invention on different rail gauges, whereby the rail gauge setting range preferably lies between 1000 mm and 1458 mm. Means for blocking the fluid transmission gear are preferably provided for passing complicated curves in the track and points, whereby the fluid transmission gear can be designed as a cylinder-piston-arrangement. The blocking means can be entirely or partially arranged in the vicinity of gearing for the transversal movement of the mount. It is, however, also possible to arrange the blocking means in the vicinity of the measuring wheels of corresponding grinding modules for both rails. In a further arrangement according to the present invention a plurality of grinding modules can be seated on the frame and corresponding front and rear measuring wheels, considered in the direction of the grinding carriage, can be pivotally joined to the frame for executing movements in vertical directions. In a further favorable embodiment, provided that the requirements to accuracy are satisfactory for an actual case of application, the grinding modules can be combined in groups on a frame, and each grinding module group is attached to a support which is pivotally seated on the frame in a plane at least approximately parallel to one of the rails. In this case, the measuring wheels are advantageously associated to the grinding module groups. Each of the measuring wheels which are arranged between the grinding module groups is active for the two neighboring grinding module groups which, in the vicinity of the measuring wheels located between them, are pivotally joined to one another about an axis which is arranged substantially at right angles to the rail to be ground. The invention will be explained in more detail by virtue of the schematical drawings. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 a plan view of a grinding carriage substantially characterized by wheel axles between which arrangements according to the present invention (reprofiling units) are provided, FIG. 2 a lateral view of an arrangement according to the present invention with three grinding modules, FIG. 3 a plan view of the arrangements according to the present invention of FIG. 2, FIG. 4 an end view of a grinding module of the reprofiling unit, FIG. 5 a perspective view of a grinding module, FIG. 6 a lateral view of a second arrangement according to the present invention, and FIG. 7 a control logic of a fluid transmission gear with a double cylinder. DETAILED DESCRIPTION OF THE INVENTION In FIG. 1 a grinding carriage 10 moving in x-direction and having a central line m is provided with two wheel axles 11 , 12 , whereby the wheel axles 11 , 12 are seated for rotation substantially about vertical axes X—X on the carriage. Pairs of wheels 13 , 14 of the grinding carriage 10 run on rails 15 , 16 of a track, rail heads of which shall be worked on and reprofiled. Thereby wheel flanges 17 , 18 of the wheels 13 , 14 run on inner edges of the rails 15 , 16 , indicated by dashed curved line. Reprofiling units 19 , 20 , 21 , 22 are attached to the grinding carriage 10 between the wheel axles 11 , 12 . By use of the reprofiling units 19 , 20 , 21 , 22 , the heads of the rails 15 , 16 will be worked on. Due to the curvature of the rails 15 , 16 , the wheel axles 11 , 12 are inclined relative to the central line m of the grinding carriage 10 by an angle of ±φx towards a not shown center of curvature. The curvature of the rails 15 , 16 also effects deviations of secants gx for the reprofiling units fixedly connected to the grinding carriage 10 , whereby these secant deviations also affect the grinding tools in the reprofiling units 19 to 22 and their position relative to the rails 15 , 16 . With too small radii of curvature of the rails 15 , 16 , the grinding tools will not work the entire width of the rail head, respectively they will work on the rail head in an improper manner. This disadvantage is eliminated by the arrangement according to the present invention. In FIGS. 2 and 3, the arrangement according to the present invention comprises a frame 23 with grinding modules 24 , 25 , 26 , whereby the frame 23 , by the aid of drive means 29 , 30 , is arranged vertically displaceable in the direction of a double arrow 56 at guide means 27 , 28 which, in turn, are secured to the (here not shown) grinding carriage. The drive means 29 , 30 can be pneumatically operating ones. Each of the grinding modules 24 , 25 , 26 is provided with a grinding disk 31 , 32 , 33 which is driven by an electric-motor arranged in a housing 34 , 35 , 36 to grind a rail head (surface) 37 of a rail 15 (FIG. 1) and which will be, along guides 57 , 58 , 59 , driven by respective electric-motors 60 , 61 , 62 substantially at right angles to the respective rail 15 , transported to the respective rail 15 and pressed onto the same. The housing 34 , 35 , 36 is pivotally seated at a respective mount 38 , 39 , 40 about an axis at least approximately in parallel to the rail 15 to be ground, for grinding the cross-profile of the rail head. To his end electric-motors 63 , 64 , 65 are provided at the mounts 38 , 39 , 40 which, via respective motion transmission means 66 , 67 , 68 , effect the pivotal movement of the housing 34 , 35 , 36 and of the guides 57 , 58 , 59 in bearings 69 , 70 , 71 at the respective mount 38 , 39 , 40 . The mount 38 , 39 , 40 is arranged on the frame 23 for displacements along guides 41 , 42 , 43 which are substantially horizontally positioned and transversal to the rail head 37 . Drive means 44 , 45 , 46 , for example, pneumatic double cylinders are employed for transverse displacing the mounts 38 , 39 , 40 , whereby the drive means are partially attached to the associated grinding module 24 , 25 , 26 and partially to a suitably location on the frame 23 . The action of the grinding modules can be neutralized by blocking means 47 , 48 49 , for example, hydraulic blocking cylinders. To each grinding module 24 , 25 , 26 belongs a measuring wheel 50 , 51 , 52 with a wheel flange 50 ′, 51 ′, 52 ′, which is seated in an associated bearing block 53 , 54 , 55 and which can be put on the rail head 37 by displacing the frame 23 along the guides 27 , 28 . Rollers 501 , 502 , and 521 , 522 , respectively advance and trail the measuring wheels 50 and 52 in order to prevent short waves and grooves in the surface of the rail from being followed. By the aid of adjusting screws 110 , the bearing block 53 , 55 with the corresponding measuring wheel 50 , 52 and the respective rollers, advancing respectively trailing the latter, is pivotally seated at the respective grinding module 24 , 25 , 26 , with the definable pivotal movement being about a substantially horizontal axis and transverse directed to the rail head 37 . Additionally, the measuring wheels 50 , 51 , 52 and their bearing bodies 53 , 54 , 55 are displaceably arranged at the respective mount 38 , 39 , 40 transverse to the rail head 37 and parallel to the respective guide 41 , 42 , 43 . To this end respective drive means 72 , 73 , 74 . of the grinding modules 24 , 25 , 26 are provided, which are exemplarily and in more detail shown and explained in the FIGS. 4 and 5 with slight differences. To avoid any reactive forces, there is provided a tolerance s (about 0.3 to 0.8 mm) for the mean grinding module 25 relative to the rail head 37 , when the measuring wheels 50 and 52 bear upon the rail surface 37 , whereby the tolerance can be finely adjusted by a cam screw 75 . Provided that the grooving wave peaks are greater than the given tolerance, the mean grinding module 25 can escape in vertical direction by an amount f, which is indicated by a dash-point curved line 76 , so that the bridge length or the measuring length 1 between the outside measuring wheels 50 , 52 is maintained. When g 1 is the distance of the axis of rotation of the trailing roller 502 from the axis of rotation of the measuring wheel 51 , and g 2 the distance of the axis of rotation of the advancing roller 521 from the axis of rotation of the measuring wheel 51 , and when p is the projection of the distance of the axis of rotation of the measuring wheel 51 from the nearest positioned horizontal guide 42 onto the rail surface 37 , then under the condition that p<<g 1 , there will approximatively result in the point A f =( FA·h/E·I )· gi ·( l−gi ), where I is the surface momentum, E is the elastic modulus, FA is the force in the point A. When the grinding carriage 10 is moved to a place of work or from one place of work to the next one, then the grinding tools 31 , 32 , 33 are up over the rail level, that is, they and their reprofiling units 19 , 20 , 21 , 22 are withdrawn from the rails 15 , 16 and from the rail surface 37 , respectively. After the distances between the grinding tools of the reprofiling units associated to the rails 15 and 16 have already been adjusted by the aid of the drive means 44 , 45 , 46 , the frames 23 of the individual reprofiling units 19 to 21 are lowered in such a way that the grinding wheels 31 , 32 , 33 are directly positioned above the rails 15 , 16 to be ground. Simultaneously the measuring wheels 50 , 51 , 52 of all reprofiling units 19 to 22 are lowered down to the rails 15 , 16 and the rail surface 37 , respectively. The drive means 44 , 45 , 46 ensure that, during the grinding process, the wheel flanges 50 ′, 51 ′, 52 ′ of all the measuring. Wheels of the reprofiling units 19 to 22 are in contact to the rail heads 37 , in other words, that the measuring wheels are backlash-free guided by the rails 15 , 16 . The electric motors 34 , 35 , 36 rotate the grinding wheels 31 , 32 , 33 about the axes 77 , 78 , 79 . The inclination of the grinding wheels 31 , 32 , 33 , corresponds to the transversal profile of the rail heads 37 and is accordingly variable in transversal planes relative to the rails 15 , 16 together with the electric motors 63 , 64 , 65 and the motion transmission means 66 , 67 , 68 . Together with the variation of inclination there also are changed the positions of the guides 57 , 58 , 59 and of the slides 83 , 84 , 85 , guided by the former. The advance of the grinding tools 31 , 32 , 33 to and pressing them into contact with the rails is achieved by the electric-motors 60 , 61 , 62 via motion transmission means 80 , 81 , 82 and slides 83 , 84 , 85 . On the slides 83 , 84 , 85 there are the motor housings 34 , 35 , 36 provided for rotationally driving the grinding wheels 31 , 32 , 33 and there are seated the drive shafts 86 , 87 , 88 of the grinding wheels, themselves. After completion of the grinding process, the frame 23 is moved along the guides 27 , 28 substantially in vertical direction by aid of the drive means 29 , 30 . Thus the grinding wheels 31 , 32 , 33 are withdrawn from the rail heads 37 and all the drive means and the motors are turned off. The entire arrangement according to the present invention is made ready for transportation. FIG. 4 substantially comprises a section along a line S—S in FIG. 2, and represents an end view of the grinding module 26 : The mount 40 is pneumatically preset to the distance of the rails 15 , 16 . This is achieved, substantially in horizontal directions indicated by the double arrow 97 , by aid of the double cylinders 46 and by the pistons 94 , 95 sliding within the former. One of the pistons, in the present case piston 94 (FIG. 3) is attached to the frame 23 and the other one, 95 , is attached to the mount 40 . The blocking means 49 , which here operates pneumatically, allows to arrest the presetting, whereby the arrest is, for example, necessary when a point is passed. The piston 96 of the blocking means is, for example, fixedly connected to the mount 40 and the cylinder 49 accordingly to the frame 23 . Furthermore, the frame 23 is substantially vertically displaceable by pneumatic cylinders 30 along guides 28 in the directions indicated by the double arrow 56 . In the represented state, the frame 23 is in the upper (transportation) position. In the frame 23 , the guides 43 are arranged in pairs upon which the mount 40 may slide in axial bearings 89 . There are only one guide and two associated axial bearings 89 visible. The drive 62 , preferably an electric motor, which is fixedly connected to the guides 59 via a base 90 , moves the slide 85 via the drive transmission means, which here is a push rod 82 , the drive transmission means being pivotally connected to the slide. Thus the housing (motor) 36 , which is secured to the slide 85 , with the grinding tool 33 is pressed against the surface 37 of the rail 15 , whereby the grinding tool 33 is mounted on a not visible motor shaft. Thereby the measuring wheel 52 contacts the rail surface 37 . In order to rectify the transversal profile of the rail head, the base 90 is pivotally seated at the mount 40 in bearings 71 , which are in the vicinity of the rail 15 , the base 90 including the guides 59 , the slide 85 , to which the housing 36 for driving the grinding tool 33 and, hence, the grinding tool 33 itself, is secured. The grinding tool 33 has axial pivots 91 which are substantially in parallel to the rail 15 . A drive 65 , realized by an electric-motor, provides for a pivot motion, whereby the drive is pivotally connected to a lever 93 , which is secured to a pivot 91 by way of a push rod 92 . In FIG. 5, a measuring wheel 50 having a wheel flange 50 ′, as well as a roller 501 advancing the measuring wheel 50 , and a roller 502 trailing the measuring wheel 50 , are rotatable about axes, which are parallel to one another, and, together with the grinding module 24 , are seated in a bearing block 53 for displacements in directions indicated by the double arrow 102 . The bearing block 53 is seated for rotation about an axis U—U in a holder 98 . The holder 98 is slidingly engaged in a guidance 99 , preferably a dovetail guideway, which is in parallel to the axes of rotation of the measuring wheel 50 , the roller 501 and 502 , and is rigidly connected to a mount 38 . An adjustment screw 110 permits to adjust the bearing block 53 by pivotal movements about the axis U—U. A drive means in the form of an electric-motor 72 is secured to the mount 38 , which moves a push rod 100 in its axial direction. To the end of the push rod 100 , projecting from out of the electric-motor 72 , one arm of a three-armed lever 101 is pivotally connected, the lever, which is seated at the mount 38 , is connected to the holder 98 via another arm. The drive means 72 with the lever 101 , the holder 98 and its guiding device 99 is, for the grinding process, adjusted in a manner that the measuring wheel 50 with its wheel flange 50 , is positioned as desired relative to the mount 38 according to the set grinding angle a with respect to the transversal profile of the rail. At the mount 38 , a housing 103 is seated for rotations on pivots 104 in bearings 69 , only one of which is visible in the vicinity of the bearing block 53 , whereby the rotations are about an axis, which is in parallel to the double arrow 102 . Similar as in FIG. 4, an electric motor 63 , which is secured to the mount 38 , provides for the rotations, whereby the electric motor 63 acts upon a lever 105 via an axially displaceable push rod 92 . The lever 105 is rigidly connected to a not visible pivot. In the housing 103 , a substantially not visible slide 106 (similar to the slide 83 in FIG. 2) is displaceable along guides 57 substantially vertically and at right angles to the direction of displacement 102 . The slide 106 supports the housing 34 of the drive motor for the grinding tool 31 . An electric motor 60 which is attached to the outside of the housing 103 is employed for displacing the slide 106 , whereby the electric motor cooperates with a motion transmission means 80 which is engaged with the slide 106 . Sliding elements 108 for the not shown guides ( 41 in FIG. 2 and 3) are attached to the mount 38 . Furthermore, a bearing block 109 is provided at the mount 38 for pivotally seating the pistons which, according to FIG. 3 slide within the cylinder 47 and in a part of the double cylinder 44 . In FIG. 6, a frame 23 with slide bearing pairs 111 , 112 are displaceable along vertical guide pairs 27 , 28 , whereby the left half shows the frame in a sectional view, and the right half in a side view. The frame 23 is substantially aligned parallel to the rail head 37 to be worked on, and it is provided with at least one stabilizing cross-tie 107 , approximately in the center of its long side. To the right and to the left of the cross-tie 107 , there are arranged, on each side, three cylindrical guides 113 and 114 , respectively. The three cylindrical guides 113 and 114 are arranged in a horizontal plane in parallel to the rail head 37 and at right angles to the drawing plane, whereby respective guide elements 115 and 116 , respectively, of a slide 117 and 118 , respectively, are dispiaceably seated on the respective three cylindrical guides. One support plate 121 and 122 , respectively, is pivotally (by about 15°) seated approximately centrally on each slide 117 , 118 by way of a bearing bolt 119 and 120 , respectively, each, for rotating about a vertical axis V—V and W—W, respectively. On each side of the bearing bolt 119 , a mount 123 , 124 each including one grinding module 125 , 126 , is attached to the support plate 121 . In the same way on each side of the bearing bolt 120 , a mount 127 , 128 each including one grinding module 129 , 130 , is rigidly connected to the support plate 122 . The mounts 123 , 124 , 127 , 128 and the grinding modules 125 , 126 , 129 , 130 are designed and arranged in analogy to FIGS 2 , 4 , 5 . Hence, the grinding modules 125 , 126 , 129 , 130 can be rotated about axes Y—Y in their respectively associated mounts 123 , 124 , 127 , 128 , whereby the axes Y—Y are in parallel to the rail heads 37 ; thereby the amounts of rotation of the grinding modules on the support plate 121 can differ (by 1-3) from the amounts of rotation of the grinding modules on the support plate 122 , when grinding different facings, since the modules attached to one support plate only are provided with one device 145 , 146 , each, for rotations about the axis Y—Y. In FIG. 6, the grinding modules 125 and 130 are shown in sectional view, whereas the grinding modules 126 and 129 are shown in elevation. In the representation, all grinding modules are shown in a vertical plane parallel to the rail head 37 . Two measuring wheels 131 , 132 and 133 , 132 , respectively, are associated to the respective support plates 121 and 122 , and the grinding modules 125 , 126 and 129 , 130 , respectively, which are correspondingly associated to the support plates. Thereby the mean measuring wheel 132 acts for both support plates 121 , 122 . The measuring wheels 131 , 132 , 133 are seated in respectively associated bearing blocks 134 , 135 , 136 and are seated at the respective mount via axes U—U transverse to the rail head 37 . Adjustment screws 137 , 138 , 139 , 140 are adapted to improve the position of the measuring wheels 131 , 132 , 133 relative to the corresponding mount 125 , 126 , 129 , 130 . Suitable drive means 147 , 148 , 149 , 150 are provided for each mount for adjustment of the measuring wheels 131 , 132 , 133 relative to the respective mount 123 , 124 , 127 , 128 . The common measuring wheel 132 is rigidly connected to the support plate 121 via an arm 141 and the mount 124 . The two units secured to the support plates 121 and 122 are articulated to one another by a hinge 142 in the vicinity of the common measuring wheel 132 . Due to an elongated slot 143 , the hinge 142 allows for a slight clearance, which is adapted to permit the passage through the smallest curves to be passed by the respective grinding carriage, and which is parallel to the driving direction and, hence, parallel to the rall head 37 . In analogy to FIG. 2 and 5, rollers 144 are associated to the measuring wheels 131 , 132 133 . Two drive means 151 , 152 and 153 , 154 , respectively, are associated to eah support plate unit 121 , 122 , the drive means being in the form of pneumatically operating double cylinders are provided for executing the transversal motion of the support plates 121 , 122 . Thereby, the individual cylinders of each double cylinder are arranged on top of each other. Each drive means 151 to 154 is additionally provided with a blocking means 155 , 156 , 157 , 158 for blocking the drive action, the blocking means 155 , 156 , 157 , 158 being designed as a hydraulically operating cylinder-piston combination. The pneumatically and hydraulically operating cylinders and pistons are in a suitable manner connected partially to the framne 23 and partially to the mounts 123 , 124 , 127 , 128 . Due to the articulated connection of the support plate units 121 and 122 it is ensured that the grinding procedure can be efficiently and precisely carried out even with the smallest radii (15-20 m), hence, that the measuring wheels neither jump off the rail heads to be ground nor reactive forces result. As to the remaining, the disclosure with respect to FIGS. 1 to 5 is valid in its general sense. In FIG. 7 there are substantially shown a fluid gear 159 for a grinding module 160 for a right rail 15 and a fluid gear 161 for a grinding module 162 for a left rail 16 . Each of the fluid gears 159 , 161 is gas driven and comprises a double cylinder, in the cylinder chambers of which, 1591 and 1611 , respectively, and 1592 and 1612 , respectively, pistons 1593 and 1613 , respectively, and 1594 and 1614 , respectively, are arranged for being displaced in opposition to one another. The pistons 1593 and 1613 are each articulated to the respective module 160 , 162 and pistons 1594 and 1614 , respectively, are articulated to the associated frame 167 , 168 . A measuring wheel 163 and 164 , respectively, having each a respective wheel flange 163 ′, 164 ′ is associated to each grinding module 160 , 162 . Furthermore, a fluid blocking device 165 is represented, which blocks the action of the right and the left fluid transmission gear 159 , 161 when, for example, the grinding carriage ( 10 in FIG. 1) passes a point. The blocking device 165 prevents the fluid transmission gear 159 , 161 from pressing the wheel flanges 163 ′, 164 ′ of the measuring wheels 163 , 164 against the rails within the point. This is of importance as to the operation of the arrangement according to the present invention since only the wheel flanges 163 ′, 164 ′ are provided with sensorial functions in the grinding procedure. The blocking device 165 is hydraulically operated (for example, by glycol) and has two cylinders 1651 , 1652 which are articulated to the corresponding frame 167 and 168 , respectively. In the cylinders, pistons 1653 and 1654 , respectively, are slidingly arranged which are articulated to the respectively associated grinding modules 160 , 162 . The cylinders 1651 , 1652 are connected to a fluid reservoir 171 via two-way valves 169 , 170 . Furthermore, control means 166 are provided which control the state of pressure in the fluid transmission gear 159 , 161 in dependence on the operation position, the positioning position and the position of rest of the grinding modules 160 , 162 . In the following, the cylinders 1591 and 1611 are referred to as positioning cylinders P 1 , and the cylinders 1592 and 1612 are referred to as working cylinders P 2 . Each cylinder P 1 can take the positions A 1 , B 1 , C 1 , and each cylinder P 2 can take the positions A 2 , B 2 , C 2 . Before the grinding procedure can start, the grinding modules 160 , 162 have to be set to the rail gauge S, whereby there remains at first, for safety reasons, an air gap between the wheel flanges 163 ′, 164 ′ and the rails 15 and 16 , respectively, on a straight line, before a lowering between the rails 15 , 16 can take place. A rail gauge r is available for the grinding module 160 (or for both grinding modules 160 , 162 ) and, correspondingly, for the measuring wheel 163 (or for both measuring wheels 163 , 164 ) for setting the rail gauge. The rail gauge r can be varied by Ar by varying the pivotal connection of the grinding modules 160 , 162 to the pistons P 1 ( 1591 , 1611 ) and to the pistons 1651 , 1652 . Only after the measuring wheels 163 , 164 have been lowered onto the respective rails 15 , 16 the fluid transmission gears 159 , 161 and the fluid blocking devices 165 are activated by the control means 166 . In the positioning operation, starting from a position of rest, which can be, in principal, as desired, the pistons 1593 and 1613 take within the positioning cylinders P 1 the positions C 1 , and the pistons 1594 and 1614 take within the working cylinders P 2 the position C 2 . In the working position the control means 166 affects the cylinders P 1 and P 2 in such a way that the pistons 1593 and 1613 in the positioning cylinders P 1 are retained in the positions C 1 , and in the working cylinders P 2 the positions A 2 are on the way to be taken. With straight rails 15 , 16 , however, the position C 2 in the working cylinders P 2 is kept to, and the control means 116 biases the working cylinders P 2 to the preset nominal pressure. When the grinding machine according to FIG. 1 is now driving into an arc of circle, and when taking into consideration the module 160 across the rail 15 , then the grinding module is displaced by a distance gx relative to the center m (FIG. 1) of the carriage. The piston 1594 moves from C 2 towards A 2 by the distance gx, since the piston 1593 already takes its end position C 1 . Conversely, with respect to the outer curve rail 16 , there is valid that the piston 1613 from C 1 and, hence, the grinding module 162 by the distance gx will be forced to the outside in direction of A 1 , since the piston 1612 is already in its end position C 2 . When passing through alternating curves, the pistons of P 1 and P 2 move in direction of B 1 and B 2 , due to the equal gas pressure in P 1 and P 2 initiated by the control means. Thus, a dynamic balance of displacement is possible in horizontal direction, when there are curves passed through. In the transportation state of the grinding carriage, that is, when there are no reprofiling operations carried out, the grinding modules are entirely displaced to the interior, relative to the center m of the carriage. The blocking device 165 of FIG. 7 allows the same adjustment path for each piston 1653 and 1654 , respectively, in the associated cylinder 1651 and 1652 , respectively, as the fluid transmission gear 159 , 161 does for the pistons 1593 , 1594 and 1613 , 1614 , respectively, in the double cylinders 1591 , 1592 and 1611 , 1612 , respectively. The two-way valves 169 , 170 are pneumatically controlled by the control means 166 . FIG. 7 shows the hydraulic circuit at a zero pressure state, the two-way valves 169 , 170 do not block the hydraulic circuit to the fluid reservoir 171 . In this state the grinding modules 160 , 162 can be freely positioned, pressed into contact and lowered. When the two-way valves 169 , 170 are blocked towards the reservoir 171 , the fluid can only move between and in the cylinders 1651 , 1652 , the action of the fluid transmission gear 159 , 161 is blocked, the grinding modules 160 , 162 and their measuring wheels 163 , 164 are maintained in the blocked state. Thus, one measuring wheel will always be the guiding one at superelevations in the rails and in points. This will be the measuring wheel in the inner curve at superelevations and the track-bound measuring wheel in the points. The hydraulic duct can be extended mirror-invertedly for further modules, so that further modules can be added and can be combined to form groups. However, one group should not comprise more than three or four module pairs. It is also possible to attach the blocking means to the bearing blocks and/or to have the blocking means manufactured with one cylinder only. All features disclosed in the specification, in the subsequent claims, and in the drawing can be substantial for the invention both, individually and in any combination with one another.

An arrangement of grinding modules in a track grinder wherein a radial mismatch in narrow track bend radii can be considered in an exact manner without occurrence of constraining forces, enabling reprofiling to be reproduced in a simple manner. The arrangement provides a grinding tool with five degrees of freedom. Each grinding module is accommodated in an at least approximately vertical manner with a frame and in an at least horizontally manner on the frame with a holder. A housing in the holder is pivotably arranged around a shaft that is at least approximately parallel to the track to be ground. The grinding tool in the housing can be adjusted in a rectangular manner in relation to the track to be ground.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO OTHER APPLICATIONS [0001] N/A BACKGROUND [0002] 1. Technical Field [0003] This invention relates to wellbore communication systems and particularly to systems and methods for generating and transmitting data signals between the surface of the earth and the bottom hole assembly while drilling a borehole. [0004] 2. Related Art [0005] Wells are generally drilled into the ground to recover natural deposits of hydrocarbons and other desirable materials trapped in geological formations in the Earth's crust. A well is typically drilled using a drill bit attached to the lower end of a drill string. The well is drilled so that it penetrates the subsurface formations containing the trapped materials and the materials can be recovered. [0006] At the bottom end of the drill string is a “bottom hole assembly” (“BHA”). The BHA includes the drill bit along with sensors, control mechanisms, and the required circuitry. A typical BHA includes sensors that measure various properties of the formation and of the fluid that is contained in the formation. A BHA may also include sensors that measure the BHA's orientation and position. [0007] The drilling operations may be controlled by an operator at the surface or operators at a remote operations support center. The drill string is rotated at a desired rate by a rotary table, or top drive, at the surface, and the operator controls the weight-on-bit and other operating parameters of the drilling process. [0008] Another aspect of drilling and well control relates to the drilling fluid, called “mud”. The mud is a fluid that is pumped from the surface to the drill bit by way of the drill string. The mud serves to cool and lubricate the drill bit, and it carries the drill cuttings back to the surface. The density of the mud is carefully controlled to maintain the hydrostatic pressure in the borehole at desired levels. [0009] In order for the operator to be aware of the measurements made by the sensors in the BHA, and for the operator to be able to control the direction of the drill bit, communication between the operator at the surface and the BHA are necessary. A “downlink” is a communication from the surface to the BHA. Based on the data collected by the sensors in the BHA, an operator may desire to send a command to the BHA. A common command is an instruction for the BHA to change the direction of drilling. [0010] Likewise, an “uplink” is a communication from the BHA to the surface. An uplink is typically a transmission of the data collected by the sensors in the BHA. For example, it is often important for an operator to know the BHA orientation. Thus, the orientation data collected by sensors in the BHA is often transmitted to the surface. Uplink communications are also used to confirm that a downlink command was correctly understood. [0011] One common method of communication is called “mud pulse telemetry.” Mud pulse telemetry is a method of sending signals, either downlinks or uplinks, by creating pressure and/or flow rate pulses in the mud. These pulses may be detected by sensors at the receiving location. For example, in a downlink operation, a change in the pressure or the flow rate of the mud being pumped down the drill string may be detected by a sensor in the BHA. The pattern of the pulses, such as the frequency, the phase, and the amplitude, may be detected by the sensors and interpreted so that the command may be understood by the BHA. [0012] Mud pulse telemetry systems are typically classified as one of two species depending upon the type of pressure pulse generator used, although “hybrid” systems have been disclosed. The first species uses a valving “poppet” system to generate a series of either positive or negative, and essentially discrete, pressure pulses which are digital representations of transmitted data. The second species, an example of which is disclosed in U.S. Pat. No. 3,309,656, comprises a rotary valve or “mud siren” pressure pulse generator which repeatedly interrupts the flow of the drilling fluid, and thus causes varying pressure waves to be generated in the drilling fluid at a carrier frequency that is proportional to the rate of interruption. Downhole sensor response data is transmitted to the surface of the earth by modulating the acoustic carrier frequency. A related design is that of the oscillating valve, as disclosed in U.S. Pat. No. 6,626,253, wherein the rotor oscillates relative to the stator, changing directions every 180 degrees, repeatedly interrupting the flow of the drilling fluid and causing varying pressure waves to be generated. [0013] With reference to FIG. 1 , a drilling rig 10 includes a drive mechanism 12 to provide a driving torque to a drill string 14 . The lower end of the drill string 14 extends into a wellbore 30 and carries a drill bit 16 to drill an underground formation 18 . During drilling operations, drilling mud 20 is drawn from a mud pit 22 on a surface 29 via one or more pumps 24 (e.g., reciprocating pumps). The drilling mud 20 is circulated through a mud line 26 down through the drill string 14 , through the drill bit 16 , and back to the surface 29 via an annulus 28 between the drill string 14 and the wall of the wellbore 30 . Upon reaching the surface 29 , the drilling mud 20 is discharged through a line 32 into the mud pit 22 so that rock and/or other well debris carried in the mud can settle to the bottom of the mud pit 22 before the drilling mud 20 is recirculated. [0014] Referring now to FIG. 1 , one known wellbore telemetry system 100 is depicted including a downhole measurement while drilling (MWD) tool 34 is incorporated in the drill string 14 near the drill bit 16 for the acquisition and transmission of downhole data or information. The MWD tool 34 includes an electronic sensor package 36 and a mudflow wellbore telemetry device 38 . The mudflow telemetry device 38 can selectively block the passage of the mud 20 through the drill string 14 to cause pressure changes in the mud line 26 . In other words, the wellbore telemetry device 38 can be used to modulate the pressure in the mud 20 to transmit data from the sensor package 36 to the surface 29 . Modulated changes in pressure are detected by a pressure transducer 40 and a pump piston sensor 42 , both of which are coupled to a surface system processor (not shown). The surface system processor interprets the modulated changes in pressure to reconstruct the data collected and sent by the sensor package 36 . The modulation and demodulation of a pressure wave are described in detail in commonly assigned U.S. Pat. No. 5,375,098, which is incorporated by reference herein in its entirety. [0015] The surface system processor may be implemented using any desired combination of hardware and/or software. For example, a personal computer platform, workstation platform, etc. may store on a computer readable medium (e.g., a magnetic or optical hard disk, random access memory, etc.) and execute one or more software routines, programs, machine readable code or instructions, etc. to perform the operations described herein. Additionally or alternatively, the surface system processor may use dedicated hardware or logic such as, for example, application specific integrated circuits, configured programmable logic controllers, discrete logic, analog circuitry, passive electrical components, etc. to perform the functions or operations described herein. [0016] Still further, while the surface system processor can be positioned relatively proximate to the drilling rig (i.e., substantially co-located with the drilling rig), some part of or the entire surface system processor may alternatively be located relatively remotely from the rig. For example, the surface system processor may be operationally and/or communicatively coupled to the wellbore telemetry component 18 via any combination of one or more wireless or hardwired communication links (not shown). Such communication links may include communications via a packet switched network (e.g., the Internet), hardwired telephone lines, cellular communication links and/or other radio frequency based communication links, etc. using any desired communication protocol. [0017] Additionally one or more of the components of the BHA may include one or more processors or processing units (e.g., a microprocessor, an application specific integrated circuit, etc.) to manipulate and/or analyze data collected by the components at a downhole location rather than at the surface. [0018] The highest-performing mud pulse systems today use a single modulator, typically consisting of a stator and a rotor. The relative position between the stator and rotor, together with the drilling mud/fluid conditions, determine the amplitude of the telemetry signal generated. In addition, for a single modulator, the amplitude of the differential pressure signal generated is proportional to the square of the inverse of the flow area. The speed at which the rotor can be moved relative to the stator limits the bandwidth of the signal generated. SUMMARY [0019] To produce a desired telemetry signal, the desired telemetry signal is first determined and then decomposed into two or more component signals. For each component signal, commands are sent to an individual modulator. The individual modulators each produce individual signals according to their received commands. The individual signals from each individual modulator are combined to produce the desired telemetry signal, or the individual signals from each individual modulator are allowed to combine to produce the desired telemetry signal. A telemetry system that produces such desired telemetry signals includes an uplink transmitter/receiver pair, a downlink transmitter/receiver pair, or both pairs, wherein each uplink transmitter and each downlink receiver is disposed in a wellbore. Two or more modulators are provided, as is a telemetry signal generator having a processor capable of decomposing a desired telemetry signal into two or more component signals and issuing commands to control the two or more modulators based on the two or more component signals. [0020] Other aspects and advantages will become apparent from the following description and the attached claims. BRIEF DESCRIPTION OF THE FIGURES [0021] So that the above recited features and advantages of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof that are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. [0022] FIG. 1 is a schematic view, partially in cross-section, of prior art showing a known measurement while drilling tool and wellbore telemetry device connected to a drill string and deployed from a rig into a wellbore. [0023] FIG. 2 is a schematic drawing of an embodiment of a multi-component telemetry system, constructed in accordance with the present disclosure. [0024] FIG. 3 is a block diagram showing certain components of an embodiment of the multi-component telemetry system of FIG. 2 , in accordance with the present disclosure. [0025] FIG. 4 is a plot showing a polyphase decomposition that can be used in a multi-component telemetry system, in accordance with the present disclosure. [0026] FIG. 5 is a plot showing a wavelet/multiscale decomposition that can be used in a multi-component telemetry system, in accordance with the present disclosure. [0027] FIG. 6 is a plot showing a Fourier decomposition that can be used in a multi-component telemetry system, in accordance with the present disclosure. [0028] FIG. 7 is a plot showing two constituent waveforms and their sum, in accordance with the present disclosure. [0029] FIG. 8 is a flowchart showing the steps of an exemplary embodiment of a multi-component telemetry system, in accordance with the present disclosure. [0030] FIG. 9A is a schematic drawing of an embodiment of a carrier signal modulator in a multi-component telemetry system, in accordance with the present disclosure. [0031] FIG. 9B is a schematic drawing of an embodiment of a first flow area control modulator in a multi-component telemetry system, in accordance with the present disclosure. [0032] FIG. 9C is a schematic drawing of an embodiment of a second flow area control modulator in a multi-component telemetry system, in accordance with the present disclosure. [0033] FIG. 10A is a schematic drawing of an embodiment of a multi-component telemetry system with synchronization, in accordance with the present disclosure. [0034] FIG. 10B is a schematic drawing of an embodiment of a multi-component telemetry system with synchronization, in accordance with the present disclosure. [0035] FIG. 10C is a schematic drawing of an embodiment of a multi-component telemetry system with synchronization, in accordance with the present disclosure. [0036] FIG. 10D is a schematic drawing of an embodiment of a multi-component telemetry system without synchronization, in accordance with the present disclosure. DETAILED DESCRIPTION [0037] Some embodiments will now be described with reference to the figures. Like elements in the various figures will be referenced with like numbers for consistency. In the following description, numerous details are set forth to provide an understanding of various embodiments and/or features. However, it will be understood by those skilled in the art that some embodiments may be practiced without many of these details and that numerous variations or modifications from the described embodiments are possible. As used here, the terms “above” and “below”, “up” and “down”, “upper” and “lower”, “upwardly” and “downwardly”, and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe certain embodiments. However, when applied to equipment and methods for use in wells that are deviated or horizontal, such terms may refer to a left to right, right to left, or diagonal relationship as appropriate. [0038] FIG. 1 illustrates a well site in which various embodiments of a telemetry system having a wider bandwidth than prior art systems can be employed. The well site can be onshore or offshore. In this exemplary system, borehole 30 is formed in subsurface formations by rotary drilling in a manner that is well known. Some embodiments can also use directional drilling. [0039] Current mud pulse mechanical modulators are limited in their (rotational) motion velocities. As a result, the bandwidth of the telemetry signal generated is also limited. In many cases it is desirable to generate a wide bandwidth signal. However, it is believed that using a modulator at a higher rotational velocity will increase wear and reduce reliability. [0040] Multiple modulators may be used wherein each modulator generates one signal component, such that the combined signal has higher bandwidth than each of the individual signal components. Each modulator operates at a lower angular velocity than would a single modulator capable of producing the bandwidth of the generated signal. Signals generated by multiple modulators are additive, so long as the modulators are spaced sufficiently far apart. [0041] An example embodiment of a multiple modulator telemetry system 200 is shown in FIG. 2 . FIG. 2 shows a drill string 202 through which drilling fluid flows, as indicated by the direction arrows in the interior of drill string 202 . The drilling fluid passes through a source 204 and a source 206 . Sources 204 , 206 are preferably mud sirens or oscillatory valves. The action or rotational motion of sources 204 , 206 are respectively controlled by a telemetry signal generator 208 . [0042] Functionally, the system operates according to the block diagram of FIG. 3 . Telemetry signal generator 208 seeks to generate some desired signal and sends appropriate control signals to sources 204 , 206 , respectively (step 302 ). The signals produced from sources 204 , 206 combine to produce the desired signal (step 304 ). While only two modulators or sources 204 , 206 are shown in this exemplary embodiment, more sources could be used, if desired. [0043] There are at least two ways to exploit multiple modulators. One way is for each modulator to generate a signal such that the overall signal is a linear combination of those signals, as described briefly above. Another way is to control the effective overall flow area. This can be done, for example, by placing the modulators in sufficiently close proximity to each other. [0044] Regarding the linear decomposition, there are several ways to decompose one signal into two or more components. Examples include, but are not limited to, Fourier decomposition, wavelet or multiscale decomposition, and polyphase decomposition. To illustrate using polyphase decomposition, let the desired signal be x(t), and consider a decomposition of a signal into M components. Index m denotes the signals to be generated by the m-th modulator. We represent these modulation signals in (complex) baseband, thus a carrier term can be added: [0000] x  ( t ) = ∑ m = 0 M - 1  x m  ( t - m · T m ) . [0000] Each x m (t) is a polyphase component. The time delay between the polyphase components is determined by T m , which traditionally is fixed for all m. [0045] The polyphase components can come, for example, from a linear modulation such as: [0000] x m  ( t ) = ∑ n = 0 N - 1  c n ( m ) · g ( m )  ( t - nT s ( m ) ) . [0000] The coefficients c n (m) are information-bearing symbols. Alternatively, each x m (t) can come from other modulations such as Minimum-Shift Keying, Continuous-Phase Modulation, Phase-Shift Keying, Quadrature Amplitude Modulation, Multi-tone Modulation, etc. In some cases, it may be that each polyphase component itself cannot be decoded individually. FIG. 4 shows two graphs of exemplary polyphase decomposition components as a function of time in which the index m equals zero and the index n ranges from zero to three, and m equals one and n again ranges from zero to three. [0046] Another possible decomposition is the wavelet or multiscale decomposition Again, let index m denote the signals to be generated by the m-th modulator. We represent these modulation signals in (complex) baseband, thus the following carrier term can be added: [0000] x  ( t ) = ∑ m = 0 M - 1  ∑ n = 0 N - 1  c n ( m )  g m  ( t - sT m ) . [0000] The coefficients c n (m) again are information-bearing symbols. FIG. 5 shows two graphs of exemplary wavelet decomposition components as a function of time in which the index m equals zero and the index n ranges from zero to one, and m equals one and n ranges from zero to three. [0047] Another possible decomposition is the Fourier decomposition. Again, index m denotes the signals to be generated by the m-th modulator and we represent these modulation signals in (complex) baseband. Thus, the following carrier term can be added: [0000] x  ( t ) = ∑ m = 0 M - 1  ∑ n = 0 N - 1  c n ( m )  exp  (    2  π   kt / T ) . [0000] The coefficients c n (m) are again information-bearing symbols. For generality, we may write the above as: [0000] x  ( t ) = ∑ m = 0 M - 1  ∑ n = 0 N - 1  c n ( m )  exp  (    2  π   t / T  ( k ) ) . [0000] In this way, the subcarriers used are not necessarily contiguous nor uniformly spaced. To improve demodulation, a cyclic prefix, or postfix, or guard interval, can be added. Then, [0000] x  ( t ) = ∑ m = 0 M - 1  ∑ n = 0 N - 1  c n ( m )  exp  (    2  π   kt / T ) , for   t ∈ [ 0 , T ) , [0000] and the cyclic prefix is: [0000] x  ( t ) = ∑ m = 0 M - 1  ∑ n = 0 N - 1  c n ( m )  exp  (    2  π   kt / T ) , for   t ∈ [ - T g , 0 ) . [0000] FIG. 6 shows a graph of Fourier decomposition components as a function of time in which the index m equals zero and the index n ranges from zero to one, and m equals one and n again ranges from zero to one. The graph also shows the cyclic prefix. [0048] In FIG. 7 , we have signals x 1 (t) 702 , x 2 (t) 704 , and their sum x(t) 706 . The figure shows how the constituent amplitudes combine. The second constituent signal is seen to have slightly larger amplitude than the first since the out-of-phase signals do not sum to zero. The bandwidth of the resulting signal in this case is twice that of the component signals. [0049] The signals from two or more modulators can be combined such that the overall performance of the telemetry system is increased in terms of data rate, robustness to noise, and robustness to propagation distortion. In addition, less power is required to create the final signal than would be required by a single modulator. Because power consumption goes up with frequency and bandwidth, and because downhole power is limited, the frequency and bandwidth of a signal from a single modulator is limited. [0050] FIG. 8 shows exemplary steps of one embodiment of this disclosure. A desired telemetry signal is determined (step 802 ) and decomposed into two or more component signals (step 804 ). For each component signal, commands are sent to a mud pulse modulator (step 806 ). A separate mud pulse modulator is used for each component signal. Each mud pulse modulator produces a signal according to the received commands (step 808 ). The individual signals from each mud pulse modulator combine to produce the desired signal (step 810 ). [0051] When the modulators are in close proximity with each other, the signals generated will interact in a nonlinear fashion. FIGS. 9A , 9 B, and 9 C show multiple modulator rotors used to control the effective flow area. FIG. 9A shows a modulator 902 that rotates to generate a carrier modulation, while FIGS. 9B and 9C show modulators 904 , 906 , respectively, that generate the envelope of the signal. Let A1(z,t) and A2(z,t) describe the flow areas of the two modulators 904 , 906 , z describing a coordinate system normal to the flow direction to represent the flow area, and t describing time. The resulting differential pressure signal will be proportional to: [0000] x ( t )∝1 /A ( t ), [0000] where A(t) is the effective flow area determined by the two modulators. As an approximation, [0000] A ( t )=∫ x A 1 ( x,t )· A 2 ( x,t ) dx. [0000] Thus, by having several modulators with one or different shapes, we can generate a signal x(t) that depends on their motions. When a stator is present, or multiple modulators are present, then: [0000] A  ( t ) = ∫ z  ∏ m = 0 M - 1   A m  ( z , t )   z . [0000] As an example, one modulator can control the effective flow area between itself and a rotor, and a second modulator can rotate and effectively generate carrier modulation. [0052] The multiple modulators may be controlled by one controller and thus be inherently synchronized (see FIG. 10A ). Alternatively, the multiple modulators may each have their own controller, but share the same clock such that they are synchronized (see FIG. 10B ). The multiple modulators may each have their own controller, each with its own clock. Those clocks may (see FIG. 10C ) or may not (see FIG. 10D ) be synchronized. For each case, each controller may encode some parts of the information bits if each decomposed component can be encoded and decoded separately, or the controller may encode all the information bits if the decomposed components do not individually convey integral pieces of information. [0053] This description is intended for purposes of illustration only and should not be construed in a limiting sense. The scope of this invention should be determined only by the language of the claims that follow. The term “comprising” within the claims is intended to mean “including at least” such that the recited listing of elements in a claim are an open group. “A,” “an” and other singular terms are intended to include the plural forms thereof unless specifically excluded. [0054] It should be appreciated that while the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims.

To produce a desired telemetry signal, the desired telemetry signal is first determined and then decomposed into two or more component signals. For each component signal, commands are sent to an individual modulator. The individual modulators each produce individual signals according to their received commands. The individual signals from each individual modulator are combined to produce the desired telemetry signal, or the individual signals from each individual modulator are allowed to combine to produce the desired telemetry signal. A telemetry system that produces such desired telemetry signals includes an uplink transmitter/receiver pair, a downlink transmitter/receiver pair, or both pairs, wherein each uplink transmitter and each downlink receiver is disposed in a wellbore. Two or more modulators are provided, as is a telemetry signal generator having a processor capable of decomposing a desired telemetry signal into two or more component signals and issuing commands to control the two or more modulators.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS This is a continuation-in-part of U.S. application Ser. No. 12/317,073 filed Dec. 18, 2008 and of U.S. application Ser. No. 11/255,160 filed Oct. 20, 2005 (issued as U.S. Pat. No. 7,484,625 on Feb. 3, 2009), both of which are a continuation-in-part of U.S. application Ser. No. 11/059,584 filed Feb. 16, 2005 (issued as U.S. Pat. No. 7,159,654 on Jan. 9, 2007) which is a continuation-in-part of U.S. application Ser. No. 10/825,590 filed Apr. 15, 2004 (abandoned)—from all (applications and patents) of which the present invention and application claim the benefit of priority under the Patent Laws and all of which are incorporated fully herein in their entirety for all purposes. BACKGROUND OF THE INVENTION Field of the Invention This invention is directed to systems and methods for identifying risers used in wellbore operations; in certain aspects, to risers with wave-energizable identification apparatus thereon; and, in certain aspects to identifying using wave-energizable apparatus such as, but not limited to, radio frequency identification devices or tags. Description of Related Art The prior art discloses a variety of systems and methods for using surface acoustic wave tags or radio frequency identification tags in identifying items, including items used in the oil and gas industry such as drill pipe. (See e.g. U.S. Pat. Nos. 4,698,631; 5,142,128; 5,202,680; 5,360,967; 6,333,699; 6,333,700; 6,347,292; 6,480,811; and U.S. patent application Ser. No. 10/323,536 filed Dec. 18, 2002; Ser. No. 09/843,998 filed Apr. 27, 2001; Ser. No. 10/047,436 filed Jan. 14, 2002; Ser. No. 10/261,551 filed Sep. 30, 2002; Ser. No. 10/032,114 filed Dec. 21, 2001; and Ser. No. 10/013,255 filed Nov. 5, 2001; all incorporated fully herein for all purposes.) In many of these systems a radio frequency identification tag or “RFIDT” is used on pipe at such a location either interiorly or exteriorly of a pipe, that the RFIDT is exposed to extreme temperatures and conditions downhole in a wellbore. Often an RFIDT so positioned fails and is of no further use. Also, in many instances, an RFIDT so positioned is subjected to damage above ground due to the rigors of handling and manipulation. The present inventors have realized that, in certain embodiments, risers can be provided with effective identification apparatus. BRIEF SUMMARY OF THE PRESENT INVENTION The present invention discloses, in some aspects, member including: a body, the body having an exterior surface and two spaced-apart ends, wave energizable identification apparatus on the exterior surface of the body, the wave energizable identification apparatus wrapped in fabric material, the fabric material comprising heat-resistant non-conducting material, the wave energizable identification apparatus wrapped and positioned on the body so that the wave energizable identification apparatus does not contact the body, and the member is a riser. The present invention discloses, in some aspects a riser with a riser body having an interior surface, an exterior surface, and two spaced-apart ends; at least one identification assembly (or a plurality of) on the riser body; the identification assembly having an assembly body and a wave energizable apparatus in the body; the assembly body having an interior surface, an exterior surface, and a channel therethrough in which is positioned part of the riser body; the assembly body releasably secured on the riser body; and the wave energizable apparatus positioned within the assembly body. The present invention discloses, in certain aspects, a riser with a riser body, the body having an exterior surface, two spaced-apart ends; wave-energizable identification apparatus on the exterior surface; the wave-energizable identification apparatus held on the body with holding apparatus which, in one aspect, is a fabric wrap of fabric material, the fabric material including heat-resistant non-conducting material; and the wave-energizable identification apparatus wrapped and positioned so that the wave-energizable identification apparatus does not contact the riser body. In certain aspects, the present invention discloses such a riser in which the identification apparatus is held in place by a strap that encompasses the riser body. The present invention, in certain aspects, provides an item, an apparatus, or a tubular, e.g. a piece of drill pipe, with a radio frequency identification tag either affixed exteriorly to the item, apparatus or tubular or in a recess in an end thereof so that the RFIDT is protected from shocks (pressure, impacts, thermal) that may be encountered in a wellbore or during drilling operations. In one particular aspect one or more RFIDT's are covered with heat and/or impact resistant materials on the exterior of an item. In one particular aspect, the present invention discloses systems and methods in which a piece of drill pipe with threaded pin and box ends has one or more circumferential recesses formed in the pin end into which is emplaced one or more radio frequency identification tags each with an integrated circuit and with an antenna encircling the pin end within A recess. The RFIDT (OR RFIDT'S) in a recess is protected by a layer of filler, glue or adhesive, e.g. epoxy material, and/or by a cap ring corresponding to and closing off the recess. Such a cap ring may be made of metal (magnetic; or nonmagnetic, e.g. aluminum, stainless steel, silver, gold, platinum and titanium), plastic, composite, polytetrafluoroethylene, fiberglass, ceramic, and/or cermet. The RFIDT can be, in certain aspects, any known commercially-available read-only or read-write radio frequency identification tag and any suitable known reader system, manual, fixed, and/or automatic may be used to read the RFIDT. The present invention, in certain aspects, provides an item, apparatus, or tubular, e.g. a piece of drill pipe, with one or more radio frequency identification tags wrapped in heat and impact resistant materials; in one aspect, located in an area 2-3″ in length beginning ½ from the 18 degree taper of the pin and drill pipe tool joint so that the RFIDT (or RFIDT's) is protected from shocks (pressure, impacts, thermal) that may be encountered on a rig, in a wellbore, or during wellbore (e.g. drilling or casing) operations. In one particular aspect, the present invention discloses systems and methods in which a piece of drill pie with threaded pin and box ends has one or more radio frequency identification tags each with an integrated circuit and with an antenna encircling the pin end upset area located exteriorly on the pipe, e.g. in an area ½″-2½ from a pin end 18 degree taper. The RFIDT (or RFIDT's) is protected by wrapping the entire RFIDT and antenna in a heat resistant material wrapped around the circumference of the tube body and held in place by heat resistant glue or adhesive, e.g. epoxy material which encases the RFIDT. This material is covered with a layer of impact resistant material and wrapped with multiple layers of wrapping material such as epoxy bonded wrap material. Preferably this wrapping does not exceed the tool joint OD. The RFIDT can be (as can be any disclosed herein), in certain aspects, any known commercially-available read-only or read-write radio frequency identification tag and any suitable know reader system, manual, fixed, and/or automatic may be used to read the RFIDT. Such installation of RFIDT's can be carried out in the field, in a factory, on a rig, with no machining necessary. Optionally, a metal tag designating a unique serial number of each item, apparatus, or length of drill pipe located under the wrap with the RFIDT(s) insures “Traceability” is never lost due to failure of the RFIDT(s). Replacement of failed RFIDT's can be carried out without leaving a location, eliminating expensive transportation or trucking costs. Optionally the wrap is applied in a distinctive and/or a bright color for easy identification. Determining whether an item, apparatus, or a tubular or a length of drill pipe or a drill pipe string is RFID-tagged or not is visibly noticeable, e.g. from a distance once the RFIDT's are in place. In certain particular aspects an RFIDT is encased in a ring of protective material whose shape and configuration corresponds to the shape of the pin end's recess and the ring is either permanently or removably positioned in the recess. Such a ring may be used without or in conjunction with an amount of protective material covering the ring or with a cap ring that protectively covers the RFIDT. Two or more RFIDT's may be used in one recess and/or there may be multiple recesses at different levels. In other aspects a ring is provided which is emplaceable around a member, either a generally cylindrical circular member or a member with some other shape. With an RFIDT located in a pipe's pin end as described herein, upon makeup of a joint including two such pieces of pipe, an RFIDT in one pipe's pin end is completely surrounded by pipe material—including that of a corresponding pipe's box end—and the RFIDT is sealingly protected from access by materials flowing through the pipe and from materials exterior to the pipe. The mass of pipe material surrounding the enclosed RFIDT also protects it from the temperature extremes of materials within and outside of the pipe. In other aspects [with or without an RFIDT in a recess] sensible material and/or indicia are located within a recess and, in one aspect, transparent material is placed above the material and/or indicia for visual inspection or monitoring; and, in one aspect, such sensible material and/or indicia are in or on a cap ring. A pipe with a pin end recess as described herein can be a piece of typical pipe in which the recess is formed, e.g. by machining or with laser apparatus or by drilling; or the pipe can be manufactured with the recess formed integrally thereof. In certain particular aspects, in cross-section a recess has a shape that is square, rectangular, triangular, semi-triangular, circular, semi-circular, trapezoid, dovetail, or rhomboid. It has also been discovered that the location of an RFIDT or RFIDT's according to the present invention can be accomplished in other items, apparatuses, tubulars and generally tubular apparatuses in addition to drill pipe, or in a member, device, or apparatus that has a cross-section area that permits exterior wrapping of RFIDT(s) or circumferential installation of antenna apparatus including, but not limited to, in or on casing, drill collars, (magnetic or nonmagnetic) pipe, thread protectors, centralizers, stabilizers, control line protectors, mills, plugs (including but not limited to cementing plugs), and risers; and in or on other apparatuses, including, but not limited to, whipstocks, tubular handlers, tubular manipulators, tubular rotators, top drives, tongs, spinners, downhole motors, elevators, spiders, powered mouse holes, and pipe handlers, sucker rods, and drill bits (all which can be made of or have portions of magnetizable metal or nonmagnetizable metal). In certain aspects the present invention discloses a rig with a rig floor having thereon or embedded therein or positioned therebelow a tag reader system which reads RFIDT's in pipe or other apparatus placed on the rig floor above the tag reader system. All of such rig-floor-based reader systems, manually-operated reader systems, and other fixed reader systems useful in methods and systems according to the present invention may be, in certain aspects, in communication with one or more control systems, e.g. computers, computerized systems, consoles, and/or control system located on the rig, on site, and/or remotely from the rig, either via lines and/or cables or wirelessly. Such system can provide identification, inventory, and quality control functions and, in one aspect, are useful to insure that desired tubulars, and only desired tubulars, go downhole and/or that desired apparatus, and only desired apparatus, is used on the rig. In certain aspects one or more RFIDT's is affixed exteriorly of or positioned in a recess an item, apparatus, or tubular, e.g., in one aspect, in a box end of a tubular. In certain aspects antennas of RFIDT's according to the present invention have a diameter between one quarter inch to ten inches and in particular aspects this range is between two inches and four inches. Such systems can also be used with certain RFIDT's to record on a read-write apparatus therein historical information related to current use of an item, apparatus or of a tubular member; e.g., but not limited to, that this particular item, apparatus, or tubular member is being used at this time in this particular location or string, and/or with particular torque applied thereto by this particular apparatus. In other aspects, a pipe with a pin end recess described therein has emplaced therein or thereon a member or ring with or without an RFIDT and with sensible indicia, e.g., one or a series of signature cuts, etchings, holes, notches, indentations, alpha and/or numeric characters, raised portion(s) and/or voids, filled in or not with filler material (e.g. but not limited to, epoxy material and/or nonmagnetic or magnetic metal, composite, fiberglass, plastic, ceramic and/or cermet), which indicia are visually identifiable and/or can be sensed by sensing systems (including, but not limited to, systems using ultrasonic sensing, eddy current sensing, optical/laser sensing, and/or microwave sensing). Similarly it is within the scope of the present invention to provide a cap ring (or a ring to be emplaced in a recess) as described herein (either for closing off a recess or for attachment to a pin end which has no such recess) with such indicia which can be sensed visually or with sensing equipment. It is within the scope of this invention to provide an item, apparatus, or tubular member as described herein exteriorly affixed RFIDT(s) and/or with a circular recess as described above with energizable identification apparatus other than or in addition to one or more RFIDT's; including, for example one or more surface acoustic wave tags (“SAW tags”) with its antenna apparatus in the circular apparatus. Accordingly, the present invention includes features and advantages which are believed to enable it to advance riser identification technology. Characteristics and advantages of the present invention described above and additional features and benefits will be readily apparent to those skilled in the art upon consideration of the following description of embodiments and referring to the accompanying drawings. Certain embodiments of this invention are not limited to any particular individual feature disclosed here, but include combinations of them distinguished from the prior art in their structures, functions, and/or results achieved. Features of the invention have been broadly described so that the detailed descriptions that follow may be better understood, and in order that the contributions of this invention to the arts may be better appreciated. There are, of course, additional aspects of the invention described below and which may be included in the subject matter of the claims to this invention. Those skilled in the art who have the benefit of this invention, its teachings, and suggestions will appreciate that the conceptions of this disclosure may be used as a creative basis for designing other structures, methods and systems for carrying out and practicing the present invention. The claims of this invention are to be read to include any legally equivalent devices or methods which do not depart from the spirit and scope of the present invention. What follows are some of, but not all, the objects of this invention. In addition to the specific objects stated below for at least certain preferred embodiments of the invention, other objects and purposes will be readily apparent to one of skill in this art who has the benefit of this invention's teachings and disclosures. It is, therefore, an object of at least certain preferred embodiments of the present invention to provide: New, useful, unique, efficient, nonobvious devices, risers with apparatus for identification and/or for tracking, inventory and control and, in certain aspects, such risers employing identification device(s), e.g. wave-energizable devices, e.g., one or more radio frequency identification tags and/or one or more SAW tags; New, useful, unique, efficient, nonobvious devices, systems and methods for apparatus identification, tracking, inventory and control and, in certain aspects, such systems and methods employing identification device(s), e.g. one or more RFIDT and/or one or more SAW tags; Such systems and methods in which a member is provided with one or more exteriorly affixed RFIDT's and/or one or more recesses into which one or more identification devices are placed; Such systems and methods in which the member is a cylindrical or tubular member and the recess (or recesses) is a circumferential recess around either or both ends thereof, made or integrally formed therein; Such systems and methods in which filler material and/or a cap ring is installed permanently or releasably over a recess to close it off and protect identification device(s); Such systems and methods in which aspects of the present invention are combined in a nonobvious and new manner with existing apparatuses to provide dual redundancy identification; Such systems and methods in which a sensing-containing member (flexible or rigid) is placed within or on an item; and Such systems and methods which include a system on, in, or under a rig floor, and/or on equipment, for sensing identification device apparatus according to the present invention. The present invention recognizes and addresses the problems and needs in this area and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention's realizations, teachings, disclosures, and suggestions, various purposes and advantages will be appreciated from the following description of certain embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent's object to claim this invention no matter how others may later attempt to disguise it by variations in form, changes, or additions of further improvements. The Abstract that is part hereof is to enable the U.S. Patent and Trademark Office and the public generally, and scientists, engineers, researchers, and practitioners in the art who are not familiar with patent terms or legal terms of phraseology to determine quickly from a cursory inspection or review the nature and general area of the disclosure of this invention. The Abstract is neither intended to define the invention, which is done by the claims, nor is it intended to be limiting of the scope of the invention or of the claims in any way. It will be understood that the various embodiments of the present invention may include one, some, or all of the disclosed, described, and/or enumerated improvements and/or technical advantages and/or elements in claims to this invention. Certain aspects, certain embodiments, and certain preferable features of the invention are set out herein. Any combination of aspects or features shown in any aspect or embodiment can be used except where such aspects or features are mutually exclusive. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS A more particular description of embodiments of the invention briefly summarized above may be had by references to the embodiments which are shown in the drawings which form a part of this specification. These drawings illustrate certain preferred embodiments and are not to be used to improperly limit the scope of the invention which may have other equally effective or legally equivalent embodiments. FIG. 1A is a perspective view of a pin end of a drill pipe according to the present invention. FIG. 1B is a perspective views of a pin end of a drill pipe according to the present invention. FIG. 1C is a partial cross-sectional view of the drill pipe of FIG. 1A . FIG. 1D shows shapes for recesses according to the present invention. FIG. 2 is a graphical representation of a prior art commercially-available radio frequency identification tag apparatus. FIG. 2A is a perspective view of a torus according to the present invention. FIG. 2B is a side view partially in cross-section, of the torus of FIG. 2B . FIG. 2C is a top perspective view of a torus according to the present invention. FIG. 2D is a side view in cross-section of a recess according to the present invention with the torus of FIG. 2C therein. FIG. 2E is a top view in cross-section of a torus according to the present invention. FIG. 2F is a top view of a torus according to the present invention. FIG. 2G is a side view of the torus of FIG. 2F . FIG. 2H is a side view of a torus according to the present invention. FIG. 2I is a top view of a cap ring according to the present invention. FIG. 2J is a side view of the cap ring of FIG. 2I . FIG. 2K is a top view of a cap ring according to the present invention. FIG. 2L is a side view of the cap ring of FIG. 2K . FIG. 2M is a top view of a cap ring according to the present invention. FIG. 3A is a side view, partially in cross-section, of a tubular according to the present invention. FIG. 3B is an enlarged view of a box end of the tubular of FIG. 3A . FIG. 3C is an enlarged view of a pin end of the tubular of FIG. 3A . FIG. 4A is a side schematic view of a rig according to the present invention. FIG. 4B is a side view partially in cross-section of a tubular according to the present invention. FIG. 4C is a schematic view of the system of FIG. 4A . FIG. 5A is a schematic view of a system according to the present invention. FIG. 5B is a side view of a tubular according to the present invention. FIG. 5C is a schematic view of a system according to the present invention. FIG. 5D is a schematic view of a system according to the present invention. FIG. 6 is a side view of a tubular according to the present invention. FIG. 7A is a side view of a tubular according to the present invention. FIG. 7B is a cross-section view of the tubular of FIG. 7B . FIG. 8A is a side view of a stabilizer according to the present invention. FIG. 8B is a cross-section view of the stabilizer of FIG. 8A . FIG. 8C is a side view of a centralizer according to the present invention. FIG. 8D is a cross-section view of the centralizer of FIG. 8C . FIG. 8E is a side view of a centralizer according to the present invention. FIG. 8F is a cross-section view of the centralizer of FIG. 8E . FIG. 8G is a side view of a centralizer according to the present invention. FIG. 8H is a cross-section view of the centralizer of FIG. 8E . FIG. 9A is a side cross-section view of a thread protector according to the present invention. FIG. 9B is a side cross-section view of a thread protector according to the present invention. FIG. 10A is a side cross-section view of a thread protector according to the present invention. FIG. 10B is a perspective view of a thread protector according to the present invention. FIG. 11 is a cross-section view of a thread protector according to the present invention. FIG. 12A is a schematic side view of a drilling rig system according to the present invention. FIG. 12B is an enlarged view of part of the system of FIG. 12A . FIG. 13A is a side view of a system according to the present invention. FIG. 13B is a side view of part of the system of FIG. 13A . FIG. 14A is a schematic view of a system according to the present invention with a powered mouse hole. FIG. 14B is a side view of the powered mouse hole of FIG. 14A . FIG. 14C is a cross-section view of part of the powered mouse hole of FIGS. 14 A and B. FIG. 14D is a side view of a powered mouse hole tool according to the present invention. FIG. 15A is a side view of a top drive according to the present invention. FIG. 15B is an enlarged view of part of the top drive of FIG. 15A . FIG. 16A is a side cross-section view of a plug according to the present invention. FIG. 16B is a side cross-section view of a plug according to the present invention. FIG. 17A is a perspective view of a portable RFIDT bearing ring according to the present invention. FIG. 17B is a side view of the ring of FIG. 17A . FIG. 17C is a perspective view of the ring of FIG. 17A with the ring opened. FIG. 17D is a top view of a ring according to the present invention. FIG. 17E is a top view of a ring according to the present invention. FIG. 18A is a side view of a whipstock according to the present invention. FIG. 18B is a bottom view of the whipstock of FIG. 18A . FIG. 19 is a side view of a mill according to the present invention. FIG. 20A is a perspective views of a pipe manipulator according to the present invention. FIG. 20B is a perspective views of a pipe manipulator according to the present invention. FIG. 21 is a schematic view of a system according to the present invention. FIG. 22 is a schematic view of a system according to the present invention. FIG. 23 is a schematic view of a system according to the present invention. FIG. 24 is a perspective view of a blowout preventer according to the present invention. FIG. 25 is a side view of a tubular according to the present invention. FIG. 26 is an enlargement of part of FIG. 25 . FIG. 27 is a perspective view of a tubular according to the present invention. FIG. 28 is a perspective view of a tubular according to the present invention. FIG. 29 is a perspective view of a tubular according to the present invention. FIG. 29A is a schematic of part of the tubular of FIG. 29 . FIG. 30 is a perspective view of a tubular according to the present invention. FIG. 30A is a perspective view of a tubular according to the present invention. FIG. 30B is a perspective view of a tubular according to the present invention. FIG. 31 is a schematic view of a system according to the present invention with a riser with riser sections according to the present invention. FIG. 32A is a perspective view of a riser according to the present invention. FIG. 32B is an enlargement of part of the riser of FIG. 32A . FIG. 33A is a perspective view of an identification assembly for a riser section according to the present invention. FIG. 33B is a cross-section view of the assembly of FIG. 33A . FIG. 33C is an enlargement of part of the assembly of FIG. 33A as shown in FIG. 33D . FIG. 33D is a cross-section view of the assembly of FIG. 33A . FIG. 33E is a cross-section view of the assembly of FIG. 33D . FIG. 34A is a cross-section view of a shield according to the present invention. FIG. 34B is a side view of the shield of FIG. 32A . FIG. 34C is a bottom view of the shield of FIG. 32A . FIG. 34D is an end view of the shield of FIG. 32A within a tube. FIG. 34E is a perspective view of the shield of FIG. 32A . FIG. 35 shows in cross-section shields according to the present invention. FIG. 36 shows in cross-section shields according to the present invention. FIG. 37 is a perspective view of an apparatus according to the present invention. FIG. 38 is a perspective view of an apparatus according to the present invention. FIG. 39 is a perspective view of an apparatus according to the present invention. FIG. 40A is a cross-section view of a riser identification assembly according to the present invention. FIG. 40B is a cross-section view of a riser identification assembly according to the present invention. FIG. 40C is a cross-section view of a riser identification assembly according to the present invention. Certain embodiments of the invention are shown in the above-identified figures and described in detail below. Various aspects and features of embodiments of the invention are described below and some are set out in the dependent claims. Any combination of aspects and/or features described below or shown in the dependent claims can be used except where such aspects and/or features are mutually exclusive. It should be understood that the appended drawings and description herein are of certain embodiments and are not intended to limit the invention or the appended claims. On the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims. In showing and describing these embodiments, like or identical reference numerals are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness. As used herein and throughout all the various portions (and headings) of this patent, the terms “invention”, “present invention” and variations thereof mean one or more embodiments, and are not intended to mean the claimed invention of any particular appended claim(s) or all of the appended claims. Accordingly, the subject or topic of each such reference is not automatically or necessarily part of, or required by, any particular claim(s) merely because of such reference. So long as they are not mutually exclusive or contradictory any aspect or feature or combination of aspects or features of any embodiment disclosed herein may be used in any other embodiment disclosed herein. DETAILED DESCRIPTION OF THE INVENTION FIGS. 1A-1C show a pin end 10 of a drill pipe according to the present invention which has a sealing shoulder 12 and a threaded end portion 14 . A typical flow channel 18 extends through the drill pipe from one end to the other. A recess 20 in the top 16 (as viewed in FIG. 1C ) of the pin end 10 extends around the entire circumference of the top 16 . This recess 20 is shown with a generally rectangular shape, but it is within the scope of this invention to provide a recess with any desired cross-sectional shape, including, but not limited to, the shapes shown in FIG. 1D . In one aspect an entire drill pipe piece with a pin end 10 is like the tubular shown in FIG. 3A or the drill pipe of FIG. 12B . The recess 20 (as is true for any recess of any embodiment disclosed herein) may be at any depth (as viewed in FIG. 1C ) from the end of the pin end and, as shown in FIGS. 1A-1C may, according to the present invention, be located so that no thread is adjacent the recess. It is within the scope of the present invention to form the recess 20 in a standard piece of drill pipe with a typical machine tool, drill, with a laser apparatus such as a laser cutting apparatus, or with etching apparatus. Alternatively, it is within the scope of the present invention to manufacture a piece of drill pipe (or other tubular) with the recess formed integrally in the pin end (and/or in a box end). The recess as shown in FIG. 1C is about 5 mm wide and 5 mm deep; but it is within the scope of certain embodiments of the present invention to have such a recess that is between 1 mm and 10 mm wide and between 2 mm and 20 mm deep. A cap ring 22 is installed over the recess 20 which seals the space within the recess 20 . This cap ring 22 (as may be any cap ring of any embodiment herein) may be made of any suitable material, including, but not limited to: metal, aluminum, zinc, brass, bronze, steel, stainless steel, iron, silver, gold, platinum, titanium, aluminum alloys, zinc alloys, or carbon steel; composite; plastic, fiberglass, fiber material such as ARAMID™ fiber material; KEVLAR™ or other similar material; ceramic; or cermet. The cap ring 22 may be sealingly installed using glue, adhesive, and/or welding (e.g., but not limited to Tig, Mig, and resistance welding and laser welding processes). Disposed within the recess 20 beneath the cap ring 22 , as shown in FIG. 1C , is an RFIDT device 28 which includes a tag 24 and an antenna 26 . The antenna 26 encircles the recess 20 around the pin end's circumference and has two ends, each connected to the tag 24 . The RFIDT tag device may be any suitable known device, including, but not limited to the RFID devices commercially available, as in FIG. 2 , e.g. from MBBS Company of Switzerland, e.g. its E-Units™ (TAGs) devices e.g., as in FIG. 2 . The RFIDT device 28 may be a read-only or a read-write device. It is within the scope of this invention to provide one, two, three or more such devices in a recess 20 (or in any recess of any embodiment herein). Optionally, the RFIDT device (or devices) is eliminated and a recess 20 with a particular varied bottom and/or varied side wall(s) and/or a cap ring with a nonuniform, varied, and/or structured surface or part(s) is used which variation(s) can be sensed and which provide a unique signature for a particular piece of drill pipe (as may be the case for any other embodiment of the present invention). These variations, etc. may be provided by different heights in a recess or different dimensions of projections or protrusions from a recess lower surface or recess side wall surface, by etchings thereon or on a cap ring, by cuts thereon or therein, and/or by a series of notches and/or voids in a recess and/or in a cap ring and/or by sensible indicia. Optionally, instead of the RFIDT device 28 (and for any embodiment herein any RFIDT) a SAW tag may be used and corresponding suitable apparatuses and systems for energizing the SAW tag(s) and reading them. In certain aspects of the present invention with a recess like the recess 20 as described above, a ring or torus is releasably or permanently installed within the recess with or without a cap ring thereover (like the cap ring 22 ). Such a ring or torus may have one, two, or more (or no) RFIDT's therein. FIGS. 2A and 2B show a torus 30 installable within a recess, like the recess 20 or any recess as in FIG. 1C , which includes a body 31 with a central opening 31 a . An RFIDT 32 is encased on the body 31 . The RFIDT 32 has an integrated circuit 33 and an antenna 34 which encircles the body 31 . In certain aspects the body 31 (as may be any body of any torus or ring according to the present invention) is made of metal, plastic, polytetrafluorethylene, fiberglass, composite, ceramic, or of a nonmagnetizable metal. The opening 31 a (as may be any opening of any torus or ring herein) may be any desired diameter. Optionally, or in addition to the RFIDT device 28 , and RFIDT device 28 a (or devices 28 a ) is affixed exteriorly to the pin end 10 with a multi-layer wrap as described below (see FIGS. 28, 26 ) [any RFIDT(s) or SAW tag(s) may be used for the RFIDT 28 a]. FIGS. 2C and 2D show a torus 35 which has a central opening 35 a , a body 36 and an RFIDT 37 therein with an antenna 38 that encircles the body 36 and an integrated circuit 39 . In one aspect a recess 20 a in a body for receiving a torus 35 has an upper lip 20 b (or inwardly inclined edge or edges as shown in FIG. 2D ) and the body 36 is made of resilient material which is sufficiently flexible that the torus 35 may be pushed into the recess 20 a and releasably held therein without adhesives and without a cap ring, although it is within the scope of the present invention to use adhesive and/or a cap ring with a torus 35 . FIG. 2E shows a torus 40 according to the present invention with a body 40 a which is insertable into a recess (like the recess 20 , the recess 20 a , or any recess disclosed herein) which has one or more elements 41 therein which serve as strengthening members and/or as members which provide a unique sensible signature for the torus 40 and, therefore, for any pipe or other item employing a torus 40 . The torus 40 has a central opening 40 b and may, according to the present invention, also include one, two or more RFIDT's (not shown). FIGS. 2F and 2G show a torus 44 according to the present invention insertable into any recess disclosed herein which has a body 45 , a central opening 44 a , and a series of voids 46 a , 46 b , and 46 c . With such a torus 44 made of metal, the voids 46 a - 46 c can be sensed by any sensing apparatus or method disclosed herein and provide a unique sensible signature for the torus 44 and for any item employing such a torus 44 . Any torus described herein may have such a series of voids and any such series of voids may, according to the present invention, contain any desired number (one or more) of voids of any desired dimensions. In one particular aspect, a series of voids provides a barcode which is readable by suitable known barcode reading devices. A torus 44 can be used with or without a cap ring. As desired, as is true of any torus according to the present invention, one, two, or more RFIDT's may be used within or on the torus body. Voids may be made by machining, by drilling, by etching, by laser etching, by hardfacing or using a photovoltaic process. FIG. 2H shows a torus 47 according to the present invention useful in any recess of any embodiment herein which has a series of sensible ridges 48 a - 48 f which can be made by adding material to a torus body 49 [such a torus may have visually readable indicia, e.g. alpha (letter) and/or numeric characters]. Any torus, ring, or cap ring herein may have one or more such ridges and the ridges can have different cross-sections (e.g. as in FIG. 2H ) or similar cross-sections and they can be any suitable material, including, but not limited to metal, plastic, epoxy, carbides, and hardfacing. Also, according to the present invention, a cap ring with one or more RFIDT's and/or any other sensible material and/or indicia disclosed herein may be placed around and secured to a tubular's pin end or box end without using a recess. FIG. 2M shows a cap ring 22 a , like the cap ring 22 , but with sensible indicia 22 b - 22 f made therein or thereon for sensing by an optical sensing system, an ultrasonic sensing system, an eddy current sensing system, a barcode sensing system, or a microwave sensing system. A cap ring 22 a may be releasably or permanently installed in or over a recess like any recess disclosed herein. The indicia 22 b - 22 f may be like any of the indicia or sensible structures disclosed herein. FIGS. 2I and 2J show a specific cap ring 50 according to the present invention for use with drill pipe having a pin end. The ring 50 has a body with an outer diameter 50 a of 98 mm, a thickness 50 b of 5 mm, and a wall thickness 50 c of 5 mm. FIGS. 2K and 2L show a specific cap ring 51 according to the present invention for use with a drill pipe pin end having an end portion diameter of about four inches. The ring 51 has an outer diameter 51 a of 98 mm, a thickness 51 b of 8 to 10 mm, and a wall thickness 51 c of 3 mm. It is within the scope of the present invention to provide a tubular having a box end and a pin end (each threaded or not) (e.g. casing, riser, pipe, drill pipe, drill collar, tubing), each end with an RFIDT in a recess therein (as any recess described herein) with or without a cap ring (as any described herein). FIGS. 3A-3C show a generally cylindrical hollow tubular member 480 according to the present invention with a flow channel 480 a therethrough from top to bottom and which has a threaded pin end 481 and a threaded box end 482 . The threaded box end 482 has a circumferential recess 483 with an RFIDT 484 therein. The RFIDT has an IC 485 and an antenna 486 which encircles the box end. Optionally, filler material 487 in the recess 483 encases and protects the IC 485 and the antenna 486 ; and an optional circular cap ring 488 closes off the recess. The RFIDT and its parts and the cap ring may be as any disclosed or referred to herein. Optionally, the tubular member 480 may have a shoulder recess 483 a with an RFIDT 484 a with an IC 485 a and an antenna 486 a . Filler material 487 a (optional) encases the RFIDT 484 a and, optionally, a cap ring 488 a closes off the recess. The pin end 481 has a circumferential recess 491 in which is disposed an RFIDT 492 with an IC 493 and an antenna 494 around the pin end. As with the box end, filler material and/or a cap ring may be used with the recess 491 . Antenna size is related to how easy it is to energize an IC and, therefore, the larger the antenna, the easier [less power needed and/or able to energize at a greater distance] to energize: and, due to the relatively large circumference of some tubulars, energizing end antennas is facilitated. FIG. 4A shows a system 70 according to the present invention with a rig 60 according to the present invention which has in a rig floor 61 a reading system 65 (shown schematically) for reading one or more RFIDT's in a drill pipe 66 which is to be used in drilling a wellbore. The reading system 65 incorporates one or more known reading apparatuses for reading RFIDT's, including, but not limited to suitable readers as disclosed in the prior art and readers as commercially available from MBBS Co. of Switzerland. The present invention provides improvements of the apparatuses and systems disclosed in U.S. patent application Ser. No. 09/906,957 filed Jul. 16, 2001 and published on Feb. 7, 2002 as Publication No. 2002/0014966. In an improved system 70 according to the present invention a drill pipe 66 ( FIG. 4B ) is like the drill pipes 16 in U.S. patent application Ser. No. 09/906,957, but the drill pipe 66 has a recess 67 with a torus 68 therein having at least one RFIDT 69 (shown schematically in FIG. 4B ) and a cap ring 68 a over the torus 68 . The drill pipe 66 may be connected with a tool joint 76 to other similar pieces of drill pipe in a drill string 77 (see FIG. 4A ) as in U.S. patent application Ser. No. 09/906,957 (incorporated fully herein) and the systems and apparatuses associated with the system 70 ( FIG. 4A and FIG. 4C ) operate in a manner similar to that of the systems 10 and the system of FIG. 1B of said patent application. Drill string 77 includes a plurality of drill pipes 66 coupled by a plurality of tool joints 76 and extends through a rotary table 78 , and into a wellbore through a bell nipple 73 mounted on top of a blowout preventer stack 72 . An identification tag (e.g. an RFIDT) 71 is provided on one or more drilling components, such as illustrated in FIG. 4A , associated with the system 70 , or the drill pipe 66 . An electromagnetic signal generator system 74 that includes an antenna and a signal generator is positioned proximate to an identification tag, for example just below rotary table 78 as illustrated in FIG. 4A . Electromagnetic signal generator system 74 establishes a communications link with an identification tag 71 to energize the antenna, interrogate it, and to convey information relating to the equipment or drill pipe. The drilling system 70 includes the rig 60 with supports 83 , a swivel 91 , which supports the drill string 77 , a kelly joint 92 , a kelly drive bushing 93 , and a spider 79 with an RFIDT sensor and/or reader 79 a . A tool joint 76 is illustrated in FIG. 4A as connecting two drilling components such as drill pipes 66 . The identification tag 71 (or the RFIDT 69 read by the system 65 ) is operated to communicate a response to an incoming electromagnetic signal generated by electromagnetic signal generator system 74 (or by the system 65 ) that includes information related to the drilling component with the identification tag. The information may be used, for example, to inform an operator of system 70 of a drilling component's identity, age, weaknesses, previous usage or adaptability. According to the teachings of the present invention, this information may be communicated while drill system 70 is in operation. Some or all of the information provided in an identification tag may assist an operator in making a determination of when drilling components need to be replaced, or which drilling components may be used under certain conditions. The electromagnetic signal communicated by an identification tag or RFIDT may provide general inventory management data (such as informing an operator of the drilling components availability on the drilling site, or the drilling component's size, weight, etc.), or any other relevant drilling information associated with the system. Additional drill string components 84 , which are illustrated in FIG. 4A in a racked position, may be coupled to drill pipe 66 and inserted into the well bore, forming a portion of the drill string. One or more of drill string components may also include identification tags or RFIDT's. FIG. 4C shows typical information that may be included within an identification tag's or RFIDT's, antenna as the antenna cooperates with electromagnetic signal generator 74 and/or the system 65 to transmit an electromagnetic energizing signal 85 to an identification tag 71 (or 69 ). The electromagnetic signal generators use an antenna to interrogate the RFIDT's for desired information associated with a corresponding pipe or drilling component. The electromagnetic signal 85 is communicated to an RFIDT that responds to the transmitted electromagnetic signal by returning data or information 86 in an electromagnetic signal form that is received by one of the antennas, and subsequently communicated to a reader 87 which may subsequently process or simply store electromagnetic signal 86 . The reader 87 may be handheld, i.e. mobile, or fixed according to particular needs. The RFIDT's 69 and 71 may be passive (e.g. requiring minimal incident power, for example power density in the approximate range of 15-25 mW/cm 2 ) in order to establish a communications link between an antenna and the RFIDT. “Passive” refers to an identification tag not requiring a battery or any other power source in order to function and to deriving requisite power to transmit an electromagnetic signal from an incoming electromagnetic signal it receives via an antenna. Alternatively, an RFIDT (as may any in any embodiment herein) may include a battery or other suitable power source that would enable an RFIDT to communicate an electromagnetic signal response 86 . Antennas are coupled to reader 87 by any suitable wiring configuration, or alternatively, the two elements may communicate using any other appropriate wireless apparatus and protocol. The reader 87 is coupled to a control system which in one aspect is a computer (or computers) 88 which may include a monitor display and/or printing capabilities for the user. Computer 88 may be optionally coupled to a handheld reader 89 to be used on the rig or remote therefrom. Computer 88 may also be connected to a manual keyboard 89 a or similar input device permitting user entry into computer 88 of items such as drill pipe identity, drill string serial numbers, physical information (such as size, drilling component lengths, weight, age, etc.) well bore inclination, depth intervals, number of drill pipes in the drill string, and suspended loads or weights, for example. The computer 88 may be coupled to a series of interfaces 90 that may include one or more sensors capable of indicating any number of elements associated with drill rig derrick 83 , such as: a block travel characteristic 90 a , a rotation counter characteristic 90 b , a drill string weight 90 c , a heave compensator 90 d , and a blowout preventer (BOP) distance sensor 90 e . A micro-controller may include one or more of these sensors or any other additional information as described in U.S. application Ser. No. 09/906,957. The control system may be or may include a microprocessor based system and/or one or more programmable logic controllers. A drill pipe 66 with an RFIDT 69 and an RFIDT 71 provides a redundancy feature for identification of the drill pipe 66 so that, in the event one of the RFIDT's fails, the other one which has not failed can still be used to identify the particular drill pipe. This is useful, e.g. when the RFIDT 71 , which has relatively more exposure to down hole conditions, fails. Then the RFIDT 69 can still be used to identify the particular piece of drill pipe. It is within the scope of the present invention for any item according to the present invention to have two (or more RFIDT's like the RFIDT 69 and the RFIDT 71 . Optionally, or in addition to the RFIDT 69 , an RFIDT 69 a (or RFIDT's 69 a ) may be affixed exteriorly of the pipe 66 with wrap material 69 b (as described below, e.g. as in FIGS. 25-32 ). FIGS. 5A-5D present improvements according to the present invention of prior art systems and apparatuses in U.S. Pat. No. 6,480,811 B2 issued Nov. 12, 2002 (incorporated fully herein for all purposes). FIG. 5B shows schematically and partially a drill pipe 91 with an RFIDT 92 (like the identifier assemblies 12 , U.S. Pat. No. 6,604,063 B2 or like any RFIDT disclosed herein and with an RFIDT 99 , (as any RFIDT disclosed herein in a drill pipe's pin end). It is within the scope of the present invention to provide any oilfield equipment disclosed in U.S. Pat. No. 6,604,063 B2 with two (or more) RFIDT's (e.g., one in an end and one in a side, e.g. like those shown in FIG. 5B ). FIGS. 5A, 5C and 5D show an oilfield equipment identifying apparatus 100 according to the present invention for use with pipe or equipment as in FIG. 5B with two (or more) RFIDT's on respective pieces 114 of oilfield equipment. The RFIDT's may be any disclosed or referred to herein and those not mounted in a recess according to the present invention may be as disclosed in U.S. Pat. No. 6,480,811 B2 indicated by the reference numerals 112 a and 112 b on pieces of equipment 114 a and 114 b with RFIDT's in recesses according to the present invention shown schematically and indicated by reference numerals 109 a , 109 b ; and/or one or more RFIDT's may be affixed exteriorly (see e.g., FIGS. 25, 26 ) to either piece 114 of oilfield equipment. Each of the identifier assemblies 112 and RFIDT's like 109 a , 109 b are capable of transmitting a unique identification code for each piece of pipe or oilfield equipment. The oilfield equipment identifying apparatus 100 with a reader 118 is capable of reading each of the identifier assemblies and RFIDT's. The reader 118 includes a hand-held wand 120 , which communicates with a portable computer 122 via a signal path 124 . In one embodiment, each identifier assembly 112 includes a passive circuit as described in detail in U.S. Pat. No. 5,142,128 (fully incorporated herein for all purposes) and the reader 118 can be constructed and operated in a manner as set forth in said patent or may be any other reader or reader system disclosed or referred to herein. In use, the wand 120 of the reader 118 is positioned near a particular one of the identifier assemblies 112 or RFIDT's. A unique identification code is transmitted from the identifier assembly or RFIDT to the wand 120 via a signal path 126 which can be an airwave communication system. Upon receipt of the unique identification code, the wand 120 transmits the unique identification code to the portable computer 122 via the signal path 124 . The portable computer 122 receives the unique identification code transmitted by the wand 120 and then decodes the unique identification code, identifying a particular one of the identifier assemblies 112 or RFIDT's and then transmitting (optionally in real time or in batch mode) the code to a central computer (or computers) 132 via a signal path 134 . The signal path 134 can be a cable or airwave transmission system. FIG. 5C shows an embodiment of an oilfield equipment identifying apparatus 100 a according to the present invention which includes a plurality of the identifier assemblies 112 and/or RFIDT's 109 which are mounted on respective pieces 114 of pipe or oilfield equipment as described above. The oilfield equipment identifying apparatus includes a reader 152 , which communicates with the central computer 132 . The central computer 132 contains an oilfield equipment database (which in certain aspects, can function as the oilfield equipment database set forth in U.S. Pat. No. 5,142,128). In one aspect the oilfield equipment database in the central computer 132 may function as described in U.S. Pat. No. 5,142,128. In one aspect the oilfield equipment identifying apparatus 100 a is utilized in reading the identifier assemblies 112 (and/or RFIDT's 109 ) on various pieces 114 of pipe or oilfield equipment located on a rig floor 151 of an oil drilling rig. The reader 152 includes a hand-held wand 156 (but a fixed reader apparatus may be used). The hand-held wand 156 is constructed in a similar manner as the hand-held wand 120 described above. The wand 156 may be manually operable and individually mobile. The hand-held wand 156 is attached to a storage box 158 via a signal path 160 , which may be a cable having a desired length. Storage box 158 is positioned on the rig floor 151 and serves as a receptacle to receive the hand-held wand 156 and the signal path 160 when the hand-held wand 156 is not in use. An electronic conversion package 162 communicates with a connector on the storage box 158 via signal path 164 , which may be an airway or a cable communication system so that the is electronic conversion package 162 receives the signals indicative of the identification code stored in the identifier assemblies 112 and/or RFIDT's, which are read by the hand-held wand 156 . In response to receiving such signal, the electronic conversion package 162 converts the signal into a format which can be communicated an appreciable distance therefrom. The converted signal is then output by the electronic conversion package 162 to a buss 166 via a signal path 168 . The buss 166 , which is connected to a drilling rig local area network and/or a programmable logic controller (not shown) in a well-known manner, receives the converted signal output by the electronic conversion package 162 . The central computer 132 includes an interface unit 170 . The interface 170 communicates with the central computer 132 via a signal path 172 or other serial device, or a parallel port. The interface unit 170 may also communicates with the buss 166 via a signal path 173 . The interface unit 170 receives the signal, which is indicative of the unique identification codes and/or information read by the hand-held wand 156 , from the buss 166 , and a signal from a drilling monitoring device 174 via a signal path 176 . The drilling monitoring device 174 communicates with at least a portion of a drilling device 178 ( FIG. 5D ) via a signal path 179 . The drilling device 178 can be supported by the rig floor 151 , or by the drilling rig. The drilling device 178 can be any drilling device which is utilized to turn pieces 114 of oilfield equipment, such as drill pipe, casing (in casing drilling operations) or a drill bit to drill a well bore. For example, but not by way of limitation, the drilling device 178 can be a rotary table supported by the rig floor 151 , or a top mounted drive (“top drive”) supported by the drilling rig, or a downhole mud motor suspended by the drill string and supported by the drilling rig. Optionally, the drilling device 178 has at least one RFIDT 178 a therein or t hereon and an RFIDT reader 178 b therein or thereon. The RFIDT reader 178 a is interconnected with the other systems as is the reader 152 , e.g. via the signal path 173 as indicated by the dotted line 173 a. The drilling monitoring device 174 monitors the drilling device 178 so as to determine when the piece 114 or pieces 114 of oilfield equipment in the drill string are in a rotating condition or a non-rotating condition. The drilling monitoring device 174 outputs a signal to the interface unit 170 via the signal path 176 , the signal being indicative of whether the piece(s) 114 of oilfield equipment are in the rotating or the non-rotating condition. The central computer 132 may be loaded with a pipe and identification program in its oilfield equipment database which receives and automatically utilizes the signal received by the interface unit 170 from the signal path 176 to monitor, on an individualized basis, the rotating and non-rotating hours of each piece 114 of oilfield equipment in the drill string. For example, when the drilling device 178 is a downhole mud motor (which selectively rotates the drill string's drill bit while the drill string's pipe remains stationary), the central computer 132 logs the non-rotating usage of each piece 114 of the drill string's pipe. In the case where the drilling device 178 is the downhole mud motor, the central computer 132 has stored therein a reference indicating that the drilling device 178 is the downhole mud motor so that the central computer 132 accurately logs the non-rotating usage of each piece 114 of oilfield equipment included in the drill string that suspends the drilling device 178 . FIG. 5D shows a system 250 according to the present invention for rotating pieces of drill pipe 114 which have at least one identifier assembly 112 and/or one RFIDT in a pin end (or box end, or both) recess according to the present invention to connect a pin connection 252 of the piece 114 to a box connection 254 of an adjacently disposed piece 114 in a well known manner. Each piece 114 may have an RFIDT in its pin end and/or box end. The system 250 includes a reader system 250 a (shown schematically) for reading the RFIDT in the pin end recess prior to makeup of a joint. The apparatus 250 can be, for example, but not by way of limitation, an Iron Roughneck, an ST-80 Iron Roughneck, or an AR 5000 Automated Iron Roughneck from Varco International and/or apparatus as disclosed in U.S. Pat. Nos. 4,603,464; 4,348,920; and 4,765,401. The reader system 250 a may be located at any appropriate location on or in the apparatus 250 . The apparatus 250 is supported on wheels 256 which engage tracks (not shown) positioned on the rig floor 151 for moving the apparatus 250 towards and away from the well bore. Formed on an upper end of the apparatus 250 is a pipe spinner assembly 258 (or tong or rotating device) for selectively engaging and turning the piece 114 to connect the pin connection 252 to the box connection 254 . Optionally the assembly 258 has an RFIDT reader 258 a . An optional funnel-shaped mudguard 260 can be disposed below the pipe spinner assembly 258 . The mudguard 260 defines a mudguard bore 262 , which is sized and adapted so as to receive the piece 114 of oilfield equipment therethrough. The apparatus 250 also may include a tong or a torque assembly or torque wrench 263 disposed below the pipe spinner assembly 258 . An opening 264 is formed through the mudguard 260 and communicates with a mudguard bore 262 . Optionally an oilfield equipment identifying apparatus 110 includes a fixed mount reader 266 for automating the reading of the RFIDT's and of the identifier assemblies 112 , rather than the hand-held wand 156 . In one embodiment a flange 268 is located substantially adjacent to the opening 264 so as to position the fixed mount reader 266 through the opening 264 whereby the fixed mount reader 266 is located adjacent to the piece 114 of oilfield equipment when the piece 114 of oilfield equipment is moved and is being spun by the pipe spinner assembly 258 . The reader(s) of the apparatus 250 are interconnected with an in communication with suitable control apparatus, e.g. as any disclosed herein. In certain aspects, the fixed mount reader 266 can be located on the apparatus 250 below the pipe spinner assembly 258 and above the torque assembly or torque wrench 263 , or within or on the spinner assembly 258 ; or within or on the torque wrench 263 . The prior art discloses a variety of tubular members including, but not limited to casing, pipe, risers, and tubing, around which are emplaced a variety of encompassing items, e.g., but not limited to centralizers, stabilizers, and buoyant members. According to the present invention these items are provided with one or more RFIDT's with antenna(s) within and encircling the item and with a body or relatively massive part thereof protecting the RFIDT. FIG. 6 shows schematically a tubular member 190 with an encompassing item 192 having therein an RFIDT 194 (like any disclosed or referred to herein as may be the case for all RFIDT's mentioned herein) with an IC (integrated circuit) or microchip 196 to which is attached an antenna 198 which encircles the tubular member 190 (which is generally cylindrical and hollow with a flow channel therethrough from one end to the other or which is solid) and with which the IC 196 can be energized for reading and/or for writing thereto. In one aspect the RFIDT 194 is located midway between exterior and interior surfaces of the encompassing item 192 ; while in other aspects it is nearer to one or these surfaces than the other. The encompassing item may be made of any material mentioned or referred to herein. The RFIDT 194 is shown midway between a top and a bottom (as viewed in FIG. 6 ) of the encompassing item 192 ; but it is within the scope of this invention to locate the RFIDT at any desired level of the encompassing item 192 . Although the encompassing item 192 is shown with generally uniform dimensions, it is within the scope of the present invention for the encompassing item to have one or more portions thicker than others; and, in one particular aspect, the RFIDT (or the IC 196 or the antenna 198 ) is located in the thicker portion(s). In certain particular aspects the encompassing item is a centralizer, stabilizer, or protector. Optionally, or in addition to the RFIDT 194 , one or more RFIDT's 194 a in wrap material 194 b may be affixed exteriorly (see e.g., FIGS. 25, 26 ) of the member 190 and/or of the encompassing item 192 . FIG. 7A shows a buoyant drill pipe 200 which is similar to such pipes as disclosed in U.S. Pat. No. 6,443,244 (incorporated fully herein for all purposes), but which, as shown in FIG. 7A , has improvements according to the present invention. The drill pipe 200 has a pin end 202 and a box end 204 at ends of a hollow tubular body 206 having a flow channel (not shown) therethrough. A buoyant element 210 encompasses the tubular body 206 . Within the buoyant element 210 is at least one RFIDT 208 which may be like and be located as the RFIDT 198 , FIG. 6 . As shown in FIG. 7B , in one aspect the buoyant member 210 has two halves which are emplaced around the tubular body 206 and then secured together. In such an embodiment either one or both ends of an antenna 201 are releasably connectable to an IC 203 of an RFIDT 208 or two parts of the antenna 201 itself are releasably connectable. As shown in FIG. 7B , antenna parts 201 a and 201 b are releasably connected together, e.g. with connector apparatus 201 c , and an end of the antenna part 201 b is releasably connected to the IC 203 . Alternatively an optional location provides an RFIDT that is entirely within one half of the buoyant member 210 , e.g. like the optional RFIDT 208 a shown in FIG. 7A . The pin end 202 may have any RFIDT therein and/or cap ring according to the present invention as disclosed herein. The two halves of the buoyant member may be held together by adhesive, any known suitable locking mechanism, or any known suitable latch mechanism (as may be any two part ring or item herein according to the present invention). It is within the scope of the present invention to provide a stabilizer as is used in oil and gas wellbore operations with one or more RFIDT's. FIGS. 8A and 8B show a stabilizer 220 according to the present invention which is like the stabilizers disclosed in U.S. Pat. No. 4,384,626 (incorporated fully herein for all purposes) but which has improvements according to the present invention. An RFIDT 222 (like any disclosed or referred to herein) is embedded within a stabilizer body 224 with an IC 223 in a relatively thicker portion 221 of the body 224 and an antenna 225 that is within and encircles part of the body 224 . Parts 225 a and 225 b of the antenna 225 are connected together with a connector 226 . The stabilizer 220 may, optionally, have a recess at either end with an RFIDT therein as described herein according to the present invention. Optionally, the stabilizer 220 may have one or more RFIDT's located as are the RFIDT's in FIGS. 6 and 7A . Various stabilizers have a tubular body that is interposed between other tubular members, a body which is not clamped on around an existing tubular members. According to the present invention such stabilizers may have one or more RFIDT's as disclosed herein; and, in certain aspects, have an RFIDT located as are the RFIDT's in FIG. 6, 7A or 8A and/or an RFIDT in an end recess (e.g. pin end and/or box end) as described herein according to the present invention. FIGS. 8C and 8D show a stabilizer 230 according to the present invention which has a tubular body 231 and a plurality of rollers 232 rotatably mounted to the body 231 (as in the stabilizer of U.S. Pat. No. 4,071,285, incorporated fully herein, and of which the stabilizer 230 is an improvement according to the present invention). An RFIDT 233 with an IC 234 and an antenna 235 is disposed within one or the rollers 232 . The stabilizer 230 has a pin end 236 and a box end 237 which permit it to be threadedly connected to tubulars at either of its ends. A recess may, according to the present invention, be provided in the pin end 236 and/or the box end 237 and an RFIDT and/or cap ring used therewith as described herein according to the present invention. The antenna 235 is within and encircles part of the roller 232 . It is within the scope of the present invention to provide a centralizer with one or more RFIDT's as disclosed herein. A centralizer 240 , FIG. 8E , is like the centralizers disclosed in U.S. Pat. No. 5,095,981 (incorporated fully herein), but with improvements according to the present invention. FIGS. 8E and 8F show the centralizer 240 on a tubular TR with a hollow body 241 with a plurality of spaced-apart ribs 242 projecting outwardly from the body 241 . A plurality of screws 244 releasably secure the body 241 around the tubular TR. An RFIDT 245 with an IC 246 and an antenna 247 is located within the body 241 . Optionally a plug 241 a (or filler material) seals off a recess 241 b in which the IC 246 is located. Optionally, or in addition to the RFIDT 245 one or more RFIDT's 245 a are affixed exteriorly of the centralizer 240 under multiple layers of wrap material 245 b (see, e.g., FIGS. 25, 26 ). FIGS. 8G and 8H show a centralizer 270 according to the present invention which is like centralizers (or stabilizers) disclosed in U.S. Pat. No. 4,984,633 (incorporated fully herein for all purposes), but which has improvements according to the present invention. The centralizer 270 has a hollow tubular body 271 with a plurality of spaced-apart ribs 272 projecting outwardly therefrom. An RFIDT 273 with an IC 274 and an antenna 275 (dotted circular line) is disposed within the body 271 with the IC 274 within one of the ribs 272 and the antenna 275 within and encircling part of the body 271 . Optionally, or in addition to the RFIDT 273 , one or more RFIDT's 273 a is affixed exteriorly to the centralizer 270 under layers of wrap material 273 b (see, e.g. FIGS. 25, 26 ). Often thread protectors are used at the threaded ends of tubular members to prevent damage to the threads. It is within the scope of the present invention to provide a thread protector, either a threaded thread protector or a non-threaded thread protector, with one or more RFIDT's as disclosed herein. FIGS. 9A, 10A, and 11 show examples of such thread protectors. FIGS. 9A and 9B and 10A and 10B show thread protectors like those disclosed in U.S. Pat. No. 6,367,508 (incorporated fully herein), but with improvements according to the present invention. A thread protector 280 , FIG. 9A , according to the present invention protecting threads of a pin end of a tubular TB has an RFIDT 283 within a body 282 . The RFIDT 283 has an IC 284 and an antenna 285 . A thread protector 281 , FIG. 9B , according to the present invention protecting threads of a box end of a tubular TL has a body 286 and an RFIDT 287 with an IC 288 and an antenna 298 within the body 286 . Both the bodies 282 and 286 are generally cylindrical and both antennas 285 and 298 encircle a part of their respective bodies. Optionally the thread protector 281 has an RFIDT 287 a within a recess 286 a of the body 286 . The RFIDT 287 a has an IC 288 a and an antenna 289 a . Optionally, any thread protector herein may be provided with a recess according to the present invention as described herein with an RFIDT and/or torus and/or cap ring according to the present invention (as may any item according to the present invention as in FIGS. 6-8G ). Optionally, or in addition to the RFIDT 283 , one or more RFIDT's 283 a is affixed exteriorly (see, e.g., FIGS. 25, 26 ) to the thread protector 280 under layers of wrap material 283 b. FIGS. 10A and 10B show a thread protector 300 according to the present invention which is like thread protectors disclosed in U.S. Pat. No. 6,367,508 B1 (incorporated fully herein), but with improvements according to the present invention. The thread protector 300 for protecting a box end of a tubular TU has a body 302 with upper opposed spaced-apart sidewalls 303 a , 303 b . An RFIDT 304 with an IC 305 and an antenna 306 is disposed between portions of the two sidewalls 303 a , 303 b . Optionally, an amount of filler material 307 (or a cap ring as described above) is placed over the RFIDT 304 . Optionally, or as an alternative, an RFIDT 304 a is provided within the body 302 with an IC 305 a and an antenna 306 a . Optionally, or as an alternative, an RFIDT 304 b is provided within the body 302 with an IC 305 b and an antenna 306 b. A variety or prior art thread protectors have a strap or tightening apparatus which permits them to be selectively secured over threads of a tubular. FIG. 11 shows a thread protector 310 according to the present invention which is like the thread protectors disclosed in U.S. Pat. No. 5,148,835 (incorporated fully herein), but with improvements according to the present invention. The thread protector 310 has a body 312 with two ends 312 a and 312 b . A strap apparatus 313 with a selectively lockable closure mechanism 314 permits the thread protector 310 to be installed on threads of a tubular member. An RFIDT 315 with an IC 316 and an antenna 317 is disposed within the body 312 . The antenna 317 may be connected or secured to, or part of, the strap apparatus 313 and activation of the lockable closure mechanism 314 may complete a circuit through the antenna. In one aspect the antenna has ends connected to metallic parts 318 , 319 and the antenna is operational when these parts are in contact. The bodies of any thread protector according to the present invention may be made of any material referred to herein, including, but not limited to, any metal or plastic referred to herein or in the patents incorporated by reference herein. FIG. 12A shows a system 400 according to the present invention which has a rig 410 that includes a vertical derrick or mast 412 having a crown block 414 at its upper end and a horizontal rig floor 416 at its lower end. Drill line 418 is fixed to deadline anchor 420 , which is commonly provided with hook load sensor 421 , and extends upwardly to crown block 414 having a plurality of sheaves (not shown). From block 414 , drill line 418 extends downwardly to traveling block 422 that similarly includes a plurality of sheaves (not shown). Drill line 418 extends back and forth between the sheaves of crown block 414 and the sheaves of traveling block 422 , then extends downwardly from crown block 414 to drawworks 424 having rotating drum 426 upon which drill line 418 is wrapped in layers. The rotation of drum 426 causes drill line 418 to be taken in or out, which raises or lowers traveling block 422 as required. Drawworks 424 may be provided with a sensor 427 which monitors the rotation of drum 426 . Alternatively, sensor 427 may be located in crown block 414 to monitor the rotation of one or more of the sheaves therein. Hook 428 and any elevator 430 is attached to traveling block 422 . Hook 428 is used to attach kelly 432 to traveling block 422 during drilling operations, and elevators 430 are used to attach drill string 434 to traveling block 422 during tripping operations. Shown schematically the elevator 430 has an RFIDT reader 431 (which may be any reader disclosed or referred to herein and which is interconnected with and in communication with suitable control apparatus, e.g. as any disclosed herein, as is the case for reader 439 and a reader 444 . Drill string 434 is made up of a plurality of individual drill pipe pieces, a grouping of which are typically stored within mast 412 as joints 435 (singles, doubles, or triples) in a pipe rack. Drill string 434 extends down into wellbore 436 and terminates at its lower end with bottom hole assembly (BHA) 437 that typically includes a drill bit, several heavy drilling collars, and instrumentation devices commonly referred to as measurement-while-drilling (MWD) or logging-while-drilling (LWD) tools. A mouse hole 438 , which may have a spring at the bottom thereof, extends through and below rig floor 416 and serves the purpose of storing next pipe 440 to be attached to the drill string 434 . With drill pipe according to the present invention having an RFIDT 448 in a pin end 442 , an RFIDT reader apparatus 439 at the bottom of the mouse hole 438 can energize an antenna of the RFIDT 448 and identify the drill pipe 440 . Optionally, if the drill pipe 440 has an RFIDT in a box end 443 , an RFIDT reader apparatus can energize an antenna in the RFIDT 446 and identify the drill pipe 440 . Optionally, the drill bit 437 has at least one RFIDT 437 a (any disclosed herein) (shown schematically). Optionally, or in addition to the RFIDT 448 , the drill pipe 440 has one or more RFIDT's 448 a affixed exteriorly to the drill pipe 440 (see, e.g., FIGS. 25, 26 ) under wrap layers 448 b. During a drilling operation, power rotating means (not shown) rotates a rotary table (not shown) having rotary bushing 442 releasably attached thereto located on rig floor 416 . Kelly 432 , which passes through rotary bushing 442 and is free to move vertically therein, is rotated by the rotary table and rotates drill string 434 and BHA 437 attached thereto. During the drilling operation, after kelly 432 has reached its lowest point commonly referred to as the “kelly down” position, the new drill pipe 440 in the mouse hole 438 is added to the drill string 434 by reeling in drill line 418 onto rotating drum 426 until traveling block 422 raises kelly 432 and the top portion of drill string 434 above rig floor 416 . Slips 445 , which may be manual or hydraulic, are placed around the top portion of drill string 434 and into the rotary table such that a slight lowering of traveling block 422 causes slips 444 to be firmly wedged between drill string 434 and the rotary table. At this time, drill string 434 is “in-slips” since its weight is supported thereby as opposed to when the weight is supported by traveling block 422 , or “out-of-slips”. Once drill string 434 is in-slips, kelly 432 is disconnected from string 434 and moved over to and secured to new pipe 440 in mouse hole 438 . New pipe 440 is then hoisted out of mouse hole 438 by raising traveling block 422 , and attached to drill string 434 . Traveling block 422 is then slightly raised which allows slips 445 to be removed from the rotary table. Traveling block 422 is then lowered and drilling resumed. “Tripping-out” is the process where some or all of drill string 434 is removed from wellbore 436 . In a trip-out, kelly 432 is disconnected from drill string 434 , set aside, and detached from hook 428 . Elevators 430 are then lowered and used to grasp the uppermost pipe of drill string 434 extending above rig floor 416 . Drawworks 424 reel in drill line 418 which hoists drill string 434 until the section of drill string 434 (usually a “triple”) to be removed is suspended above rig floor 416 . String 434 is then placed in-slips, and the section removed and stored in the pipe rack. “Tripping-in” is the process where some or all of drill string 434 is replaced in wellbore 436 and is basically the opposite of tripping out. In some drilling rigs, rotating the drill string is accomplished by a device commonly referred to as a “top drive” (not shown). This device is fixed to hook 428 and replaces kelly 432 , rotary bushing 442 , and the rotary table. Pipe added to drill string 434 is connected to the bottom of the top drive. As with rotary table drives, additional pipe may either come from mouse hole 438 in singles, or from the pipe racks as singles, doubles, or triples. Optionally, drilling is accomplished with a downhole motor system 434 a which has at least one RFIDT 434 b (shown schematically in FIG. 12A ) As shown in FIG. 12B , the reader apparatus 439 is in communication with a control apparatus 449 (e.g. any computerized or PLC system referred to or disclosed herein) which selectively controls the reader apparatus 439 , receives signals from it and, in certain aspects, processes those signals and transmits them to other computing and/or control apparatus. Similarly when the optional reader apparatus 444 is used, it also is in communication with the control apparatus 449 and is controlled thereby. With a reader at the pin end and a reader at the box end, the length of the piece of drill pipe be determined and/or its passage beyond a certain point. In one aspect the reader apparatus 439 is deleted and the reader apparatus 444 reads the RFIDT (or PFIDT's) in and/or on the drill pipe 440 as the drill pipe 440 passes by the reader apparatus 444 as the drill pipe 440 is either lowered into the mouse hole 438 or raised out of it. The reader apparatus 444 may be located on or underneath the rig floor 416 . It is within the scope of the present invention to use a reader apparatus 439 and/or a reader apparatus 444 in association with any system's mouse hole or rat hole (e.g., but not limited to, systems as disclosed in U.S. Pat. Nos. 5,107,705; 4,610,315; and in the prior art cited therein), and with so-called “mouse hole sleeves” and mouse hole scabbards” as disclosed in, e.g. U.S. Pat. Nos. 5,351,767; 4,834,604; and in the prior art references cited in these two patents. With respect to the drilling operation depicted in FIG. 12A (and, any drilling operation referred to herein according to the present invention) the drilling may be “casing drilling” and the drill pipe can be casing. FIGS. 13A and 13B show a system 450 according to the present invention which has a mouse hole 451 associated with a rig 452 (shown partially). The mouse hole 451 includes a mouse hole scabbard 454 (shown schematically, e.g. like the one in U.S. Pat. No. 4,834,604, but with improvements according to the present invention). The mouse hole scabbard 454 includes an RFIDT reader apparatus 456 (like any such apparatus described or referred to herein) with connection apparatus 458 via which a line or cable 459 connects the reader apparatus 456 to control apparatus 455 (shown schematically, like any described or referred to herein). It is within the scope of the present invention to provide, optionally, reader apparatuses (E.G. other than adjacent the pipe or adjacent a mouse hole, or tubular preparation hole) 453 and/or 459 on the rig 452 . Optionally, one or more antenna energizers are provided on a rig and reader apparatuses are located elsewhere. According to the present invention a scabbard can be made of nonmagnetic metal, plastic, polytetrafluoroethylene, fiberglass or composite to facilitate energizing of an RFIDT's antenna of an RFIDT located within the scabbard. Optionally a scabbard may be tapered to prevent a pipe end from contacting or damaging the reader apparatus 456 and/or, as shown in FIG. 13B , stops 454 a may be provided to achieve this. Various prior art systems employ apparatuses known as “powered mouse holes” or “rotating mouse hole tools”. It is within the scope of the present invention to improve such systems with an RFIDT reader apparatus for identifying a tubular within the powered mouse hole. FIGS. 14A-14C show a system 460 according to the present invention which includes a rig system 461 and a powered mouse hole 462 . The powered mouse hole 462 is like the powered mouse hole disclosed in U.S. Pat. No. 5,351,767 (incorporated fully herein for all purposes) with the addition of an RFIDT reader apparatus. The powered mouse hole 462 has a receptacle 463 for receiving an end of a tubular member. An RFIDT reader apparatus 464 is located at the bottom of the receptacle 463 (which may be like any RFIDT reader apparatus disclosed or referred to herein). A line or cable 465 connects the RFIDT reader apparatus 464 to control apparatus (not shown; like any disclosed or referred to herein). Optionally as shown in FIG. 14B , an RFIDT reader apparatus 466 in communication with control apparatus 467 is located adjacent the top of the receptacle 463 . FIG. 14D shows a rotating mouse hole tool 470 which is like the PHANTOM MOUSE™ tool commercially-available from Varco International (and which is co-owned with the present invention), but the tool 470 has an upper ring 471 on a circular receptacle 473 (like the receptacle 463 , FIG. 14C ). The upper ring 471 has an energizing antenna 472 for energizing an RFIDT on a tubular or in an end of a tubular placed into the receptacle 473 . The antenna 472 encircles the top of the receptacle 473 . The antenna 472 is connected to reader apparatus 474 (like any disclosed or referred to herein) which may be mounted on the tool 470 or adjacent thereto. The prior art discloses a wide variety of top drive units (see, e.g., U.S. Pat. Nos. 4,421,179; 4,529,045; 6,257,349; 6,024,181; 5,921,329; 5,794,723; 5,755,296; 5,501,286; 5,388,651; 5,368,112; and 5,107,940 and the references cited therein). The present invention discloses improved top drives which have one, two, or more RFIDT readers and/or antenna energizers. It is within the scope of the present invention to locate an RFIDT reader and/or antenna energizer at any convenient place on a top drive from which an RFIDT in a tubular can be energized and/or read and/or written to. Such locations are, in certain aspects, at a point past which a tubular or a part thereof with an RFIDT moves. FIGS. 15A and 15B show a top drive system 500 according to the present invention which is like the top drives of U.S. Pat. No. 6,679,333 (incorporated fully herein), but with an RFIDT reader 501 located within a top drive assembly portion 502 . The reader 501 is located for reading an RFIDT 503 on or in a tubular 504 which is being held within the top drive assembly portion 502 . Alternatively, or in addition to the reader 501 , an RFIDT reader 507 is located in a gripper section 505 which can energize and read the RFIDT 503 as the gripper section moves into the tubular 504 . In particular aspects, the tubular is a piece of drill pipe or a piece of casing. Appropriate cables or lines 508 , 509 , respectively connect the readers 501 , 507 to control apparatus (not shown, as any described or referred to herein). It is within the scope of the present invention to provide a cementing plug (or pipeline pig) with one or more RFIDT's with an antenna that encircles a generally circular part or portion of the plug or pig and with an IC embedded in a body part of the plug or pig and/or with an IC and/or antenna in a recess (as any recess described or referred to herein) and/or with one or more RFIDT's affixed exteriorly of the plug or pig. FIG. 16A shows a cementing plug 510 according to the present invention with a generally cylindrical body 512 and exterior wipers 513 (there may be any desired number of wipers). An RFIDT 514 is encased in the body 512 . An antenna 515 encircles part of the body 512 . The body 512 (as may be any plug according to the present invention) may be made of any known material used for plugs, as may be the wipers 513 . An IC 516 of the RFIDT 514 is like any IC disclosed or referred to herein. Optionally a cap ring (not shown) may be used over the recess 515 as may be filler material within the recess. Optionally, or in addition to the RFIDT 514 , one or more RFIDT's 514 a is affixed exteriorly to the plug 510 under wrap layers 514 b (see, e.g. FIGS. 25, 26 ). One or more such RFIDT's may be affixed to the plug 520 . FIG. 16B shows a cementing plug 520 according to the present invention which has a generally cylindrical body 522 with a bore 523 therethrough from top to bottom. A plurality of wipers 524 are on the exterior of the body 522 . An RFIDT 525 has an IC 526 encased in the body 522 and an antenna 527 that encircles part of the body 522 . Both antennas 515 and 527 are circular as viewed from above and extend around and within the entire circumference of their respective bodies. It is within the scope of the present invention to have the RFIDT 514 and/or the RFIDT 525 within recesses in their respective bodies (as any recess disclosed herein or referred to herein) with or without a cap ring or filler. FIGS. 17A-17D show a portable ring 530 which has a flexible body 532 made, e.g. from rubber, plastic, fiberglass, and/or composite which has two ends 531 a , 531 b . The end 531 a has a recess 536 sized and configured for receiving and holding with a friction fit a correspondingly sized and configured pin 533 projecting out from the end 531 b . The two ends 531 a , 531 b may be held together with any suitable locking mechanism, latch apparatus, and/or adhesive. As shown, each end 531 a , 531 b has a piece of releasably cooperating hook-and-loop fastener material 534 a , 534 b , respectively thereon (e.g. VELCRO™ material) and a corresponding piece of such material 535 is releasably connected to the pieces 534 a , 534 b ( FIG. 17C ) to hold the two ends 531 a , 531 b together. The body 532 encases an RFIDT 537 which has an IC 538 and an antenna 539 . Ends of the antenna 539 meet at the projection 533 —recess 536 interface and/or the projection 533 is made of antenna material and the recess 536 is lined with such material which is connected to an antenna end. Optionally, as shown in FIG. 17D the ring 530 may include one or more (one shown) protective layers 532 a , e.g. made of a durable material, e.g., but not limited to metal, KEVLAR™ material or ARAMID™ material. A hole 532 b formed when the two ends 531 a , 531 b are connected together can be any desired size to accommodate any item or tubular to be encompassed by the ring 530 . The ring 530 may have one, two or more RFIDT's therein one or both of which are read-only; or one or both of which are read-write. Such a ring may be releasably emplaceable around a member, e.g., but not limited to, a solid or hollow generally cylindrical member. Any ring or torus herein according to the present invention may have an RFIDT with an antenna that has any desired number of loops (e.g., but not limited to, five, ten, fifteen, twenty, thirty or fifty loops), as may be the case with any antenna of any RFIDT in any embodiment disclosed herein. FIG. 17E shows a portable ring 530 a , like the ring 530 but without two separable ends. The ring 530 a has a body 530 b made of either rigid or flexible material and with a center opening 530 f so it is releasably emplaceable around another member. An RFIDT 530 c within the body 530 b has an IC 530 e and an antenna 530 d. It is within the scope of the present invention to provide a whipstock with one or more RFIDT's with an RFIDT circular antenna that encircles a generally circular part of a generally cylindrical part of a whipstock. FIGS. 18A and 18B show a whipstock 540 like a whipstock disclosed in U.S. Pat. No. 6,105,675 (incorporated fully herein for all purposes), but with an RFIDT 541 in a lower part 542 of the whipstock 540 . The RFIDT 541 has an antenna 543 and an IC 544 (each like any as disclosed or referred to herein). Optionally, or in addition to the RFIDT 541 , one or more RFIDT's 541 a is affixed exteriorly to the whipstock 540 under wrap layers 541 b (see, e.g., FIGS. 25, 26 ). An RFIDT 551 (as any disclosed herein) may, according to the present invention, be provided in a generally cylindrical part of a mill or milling tool used in downhole milling operations. Also with respect to certain mills that have a tubular portion, one or both ends of such a mill may have one or more RFIDT's therein according to the present invention. FIG. 19 shows a mill 550 which is like the mill disclosed in U.S. Pat. No. 5,620,051 (incorporated fully herein), but with an RFIDT 551 in a threaded pin end 552 of a body 553 of the mill 550 . The RFIDT 551 may be emplaced and/or mounted in the pin end 552 as is any similar RFIDT disclosed herein. Optionally an RFIDT may be emplaced within a milling section 554 . Optionally, or in addition to the RFIDT 551 , one or more RFIDT's 551 a may be affixed exteriorly of the mill 550 under wrap layers 551 b (see, e.g., FIGS. 25, 26 ). The prior art discloses a variety of pipe handlers and pipe manipulators, some with gripping mechanisms for gripping pipe. It is within the scope of the present invention to provide a pipe handler with an RFIDT reader for reading an RFIDT in a tubular member which is located in one of the embodiments of the present invention as described herein. Often an end of a tubular is near, adjacent, or passing by a part of a pipe handler. An RFIDT on or in a tubular according to the present invention can be sensed by an RFIDT reader apparatus and a signal can be transmitted therefrom to control apparatus regarding the tubular's identity or other information stored in the RFIDT. FIGS. 20A and 20B show pipe manipulators 560 and 570 [which are like pipe manipulators disclosed in U.S. Pat. No. 4,077,525 (incorporated fully herein), but with improvements according to the present invention] which have movable arms 561 , 562 , (pipe manipulator 560 ) and movable arm 571 (pipe manipulator 570 ). Each manipulator has a pipe gripper 563 , 573 . Each manipulator has an RFIDT reader apparatus—apparatus 565 on manipulator 560 and apparatus 575 on manipulator 570 . Optionally, such a reader apparatus is located on a gripper mechanism. FIG. 21 shows a tubular inspection system 600 [which may be any known tubular inspection system, including those which move with respect to a tubular and those with respect to which a tubular moves, including, but not limited to those disclosed in U.S. Pat. Nos. 6,622,561; 6,578,422; 5,534,775; 5,043,663; 5,030,911; 4,792,756; 4,710,712; 4,636,727; 4,629,985; 4,718,277; 5,914,596; 5,585,565; 5,600,069; 5,303,592; 5,291,272; and Int'l Patent Application WO 98/16842 published Apr. 23, 1998 and in the references cited therein] which is used to inspect a tubular 610 (e.g., but not limited to pipe, casing, tubing, collar) which has at least one RFIDT 602 with an IC 604 and an antenna 606 and/or at least one RFIDT 602 a affixed exteriorly thereof according to the present invention. The tubular 610 may be any tubular disclosed herein and it may have any RFIDT, RFIDT's, recess, recesses, cap ring, and/or sensible material and/or indicia disclosed herein. FIG. 22 shows schematically a method 620 for making a tubular member according to the present invention. A tubular body is made—“MAKE TUBULAR BODY”—using any suitable known process for making a tubular body, including, but not limited to, known methods for making pipe, drill pipe, casing, risers, and tubing. An end recess is formed—“FORM END RECESS”—in one or both ends of the tubular member. An identification device is installed in the recess—“INSTALL ID DEVICE” (which may be any identification apparatus, device, torus ring or cap ring according to the present invention). Optionally, a protector is installed in the recess—“INSTALL PROTECTOR” (which may be any protector according to the present invention). FIG. 23 shows schematically a system 650 according to the present invention which is like the systems described in U.S. Pat. No. 4,698,631 but which is for identifying an item 652 according to the present invention which has at least one end recess (as any end recess disclosed herein) and/or within a ring or torus according to the present invention with at least one SAW tag identification apparatus 654 in the recess(es) and/or ring(s) or torus(es) and/or with an exteriorly affixed RFIDT according to the present invention. The system 650 (as systems in U.S. Pat. No. 4,698,631) has an energizing antenna apparatus 656 connected to a reader 658 which provides radio frequency pulses or bursts which are beamed through the antenna apparatus 656 to the SAW tag identification apparatus 654 . The reader 658 senses responsive signals from the apparatus 654 . In one aspect the responsive signals are phase modulated in accord with code encoded in the apparatus 654 . The reader 658 sends received signals to a computer interface unit 660 which processes the signals and sends them to a computer system 662 . It is within the scope of the present invention to provide a blowout preventer according to the present invention with one or more wave-energizable identification apparatuses, e.g. in a flange, side outlet, and/or door or bonnet or a blowout preventer. FIG. 24 shows a blowout preventer 670 according to the present invention which has a main body 672 , a flow bore 674 therethrough from top to bottom, a bottom flange 676 , a top flange 678 , a side outlet 682 , and four ram-enclosing bonnets 680 . An RFIDT 690 (like any disclosed herein) has an antenna 691 encircling and within the top flange 678 with an IC 692 connected thereto. An RFIDT 692 (like any disclosed herein) has an antenna 694 encircling and within the bottom flange 676 with an IC 695 . An RFIDT 696 (like any disclosed herein) has an antenna 697 encircling and within a bonnet 680 with an IC 698 . An RFIDT 684 (like any disclosed herein) has an antenna 685 encircling and within a flange 689 of the side outlet 682 , with an IC 686 . Optionally, or in addition to the other RFIDT's at least one RFIDT 690 a is affixed exteriorly to the blowout preventer 670 under wrap layers 690 b (see, e.g., FIG. 25, 26 ) and/or at least one RFIDT 690 c is affixed exteriorly to the blowout preventer 270 under wrap layers 690 d (see, e.g., FIG. 25, 26 ). FIGS. 25 and 26 show a tool joint 700 according to the present invention with RFIDT apparatus 720 according to the present invention applied exteriorly thereto. The tool joint 700 has a pin end 702 with a threaded pin 704 , a joint body portion 706 , an upset area 707 and a tube body portion 708 . The joint body portion 706 has a larger OD than the tube body portion 708 . The “WELDLINE’ is an area in which the tool joint is welded (e.g. inertia welded) by the manufacturer to the upset area. Although RFIDT's encased in a non-conductor or otherwise enclosed or protected can be emplaced directly on a tubular (or other item or apparatus according to the present invention, as shown in FIGS. 25 and 26 the RFIDT's to be applied to the tool joint 700 are first enclosed within non-conducting material, e.g. any suitable heat-resistant material, e.g., but not limited to, RYTON™ fabric membrane wrapping material, prior to emplacing them on the tool joint 700 . In one particular aspect, one, two, three, or four wraps, folds, or layers of commercially available RYT-WRAP™ material commercially from Tuboscope, Inc. a related company of the owner of the present invention is used which, in one particular aspect, includes three layers of RYT-WRAP™ fabric membrane material adhered together and encased in epoxy. As shown, three RFIDT's 720 are wrapped three times in the RYT-WRAP™ material 722 so that no part of any of them will contact the metal of the tool joint 700 . In one aspect such a wrapping of RYT-WRAP™ material includes RYTON™ fabric membrane material with cured epoxy wrapped around a tubular body (initially the material is saturated in place with liquid epoxy that is allowed to cure). Prior to emplacing the wrapped RFIDT's 720 on the tool joint 700 , the area to which they are to be affixed is, preferably, cleaned using suitable cleaning materials, by buffing, and/or by sandblasting as shown in FIG. 27 . Any desired number of RFIDT's 720 may be used. As shown in FIG. 29A , in this embodiment three RFIDT's 720 are equally spaced apart around the exterior of the tool joint 700 . According to the present invention, RFIDT's may be applied exteriorly to any item, apparatus, or tubular at any exterior location thereon with any or all of the layers and/or wraps disclosed herein. In the particular tool joint 700 as disclosed in FIG. 25 , the RFIDT's 720 are applied about two to three inches from a thirty-five degree taper 709 of the joint body portion 706 to reduce the likelihood of the RFIDT's contacting other items, handling tools, grippers, or structures that may contact the portion 706 . Optionally, as shown in FIG. 26 , either in the initial layers or wraps which enclose the RFIDT's 720 or in any other layer or wrap, an identification tag 724 is included with the RFIDT's, either a single such tag or one tag for each RFIDT. In one aspect the tag(s) 724 are plastic or fiberglass. In another aspect the tag(s) 724 are metal, e.g. steel, stainless steel, aluminum, aluminum alloy, zinc, zinc alloy, bronze, or brass. If metal is used, the tag(s) 724 are not in contact with an RFIDT. As shown in FIG. 28 , an adhesive may be applied to the tool joint 700 to assist in securing a layer 723 , “FOLDED MEMBRANE,” (e.g., a double layer of RYT-WRAP™ wrap material. As shown in FIG. 29 , the three RFIDT's 720 are emplaced on the layer 723 and, optionally, the identification tag or tags 724 . Optionally, as shown in FIG. 30 , part 723 a of the layer 723 is folded over to cover the RFIDT's 720 and the tag(s) 724 . If this folding is done, no adhesive is applied to the tool joint under the portion of the layer 723 which is to be folded over. Optionally, prior to folding adhesive is applied on top of the portion of the layer 723 to be folded over. Optionally, prior to folding the part 723 a over on the RFIDT's 720 and the tag(s) 724 an adhesive (e.g. two part epoxy) is applied over the RFIDT's 720 and over the tag(s) 724 . After allowing the structure of layer 723 a as shown in FIG. 30 to dry (e.g., for forty minutes to one hour), as shown in FIG. 30A the folded layer 723 with the RFIDT's 720 and tag(s) 724 is, optionally, wrapped in a layer 726 of heat shrink material and/or impact resistant material (heat resistant material may also be impact resistant). In one particular optional aspect, commercially available RAYCHEM™ heat shrink material or commercially available RCANUSA™ heat shrink material is used, centered over the folded layer 723 , with, preferably, a small end-to-end overlap to enhance secure bonding as the material is heated. As shown in FIG. 30B , optionally, the layer 726 is wrapped with layers 728 of material [e.g. RYT-WRAP™ material] (e.g. with two to five layers). In one particular aspect the layer(s) 728 completely cover the layer 726 and extend for one-half inch on both extremities of the layer 726 . Preferably, the final wrap layer of the layers 728 does not exceed the OD of the joint body portion 706 so that movement of and handling of the tool joint 700 is not impeded. Curing can be done in ambient temperature and/or with fan-assisted dryers. Any known wave-energizable apparatus may be substituted for any RFIDT herein. The present invention, therefore, in at least certain aspects, provides a member having a body, the body having at least a portion thereof with a generally cylindrical portion, the generally cylindrical portion having a circumference, radio frequency identification apparatus with integrated circuit apparatus and antenna apparatus within the generally cylindrical portion of the body, and the antenna apparatus encircling the circumference of the cylindrical portion of the body. Such a member may include one or some (in any possible combination) of the following: the body having a first end spaced-apart from a second end, and the radio frequency identification apparatus positioned within the first end of the body; the first end of the body having a recess in the first end, and the radio frequency identification apparatus is within the recess; a protector in the recess covering the radio frequency identification apparatus; the body comprising a pipe; wherein the first end is a pin end of the pipe; wherein an end of the pipe has an exterior shoulder and the radio frequency identification apparatus is within the shoulder; wherein the second end is a box end of the pipe; wherein the first end is threaded externally and the second end is threaded internally; wherein the member is a piece of drill pipe with an externally threaded pin end spaced-apart from an internally threaded box end, and the body is generally cylindrical and hollow with a flow channel therethrough from the pin end to the box end, the pin end having a pin end portion with a pin end recess therearound, and the radio frequency identification apparatus within the pin end recess and the antenna apparatus encircling the pin end portion; wherein a protector in the pin end recess covers the radio frequency identification apparatus therein; wherein the protector is a cap ring within the pin end recess which covers the radio frequency identification apparatus; wherein the protector is an amount of protective material in the recess which covers the radio frequency identification apparatus; the member having a box end having a box end portion having a box end recess therein, a box end radio frequency identification apparatus within the box end recess, the box end radio frequency identification apparatus having antenna apparatus and integrated circuit apparatus, the antenna encircling the box end portion; wherein a protector in the box end covers the radio frequency identification apparatus therein; wherein the recess has a cross-section shape from the group consisting of square, rectangular, semi-triangular, rhomboidal, triangular, trapezoidal, circular, and semi-circular; wherein the generally cylindrical portion is part of an item from the group consisting of pipe, drill pipe, casing, drill bit, tubing, stabilizer, centralizer, cementing plug, buoyant tubular, thread protector, downhole motor, whipstock, blowout preventer, mill, and torus; a piece of pipe with a pin end, the pin end having a recess therein, and sensible indicia in the recess; wherein the sensible indicia is from the group consisting of raised portions, indented portions, visually sensible indicia, spaced-apart indicia, numeral indicia, letter indicia, and colored indicia; the member including the body having a side wall with an exterior surface and a wall recess in the side wall, the wall recess extending inwardly from the exterior surface, and secondary radio frequency identification apparatus within the wall recess; and/or wherein the radio frequency identification apparatus is a plurality of radio frequency identification tag devices. The present invention, therefore, in at least certain aspects, provides a tubular member with a body with a first end spaced-apart from a second end, the first end having a pin end having a pin end recess in the first end and identification apparatus in the pin end recess, and a protector in the pin end recess protecting the identification apparatus therein. The present invention, therefore, in at least certain aspects, provides a method for sensing a radio frequency identification apparatus in a member, the member having a body, the body having at least a portion thereof with a generally cylindrical portion, the generally cylindrical portion having a circumference, wave-energizable identification apparatus with antenna apparatus within the generally cylindrical portion of the body, and the antenna apparatus encircling the circumference of the cylindrical portion of the body, the method including energizing the wave-energizable identification apparatus by directing energizing energy to the antenna apparatus, the wave-energizable identification apparatus upon being energized producing a signal, positioning the member adjacent sensing apparatus, and sensing with the sensing apparatus the signal produced by the wave-energizable identification apparatus. Such a method may include one or some (in any possible combination) of the following: wherein the sensing apparatus is on an item from the group consisting of rig, elevator, spider, derrick, tubular handler, tubular manipulator, tubular rotator, top drive, mouse hole, powered mouse hole, or floor; wherein the sensing apparatus is in communication with and is controlled by computer apparatus [e.g. including but not limited to, computer system(s), programmable logic controller(s) and/or microprocessor system(s)], the method further including controlling the sensing apparatus with the computer apparatus; wherein the energizing is effected by energizing apparatus in communication with and controlled by computer apparatus, the method further including controlling the energizing apparatus with the computer apparatus; wherein the signal is an identification signal identifying the member and the sensing apparatus produces and conveys a corresponding signal to computer apparatus, the computer apparatus including a programmable portion programmed to receive and analyze the corresponding signal, and the computer apparatus for producing an analysis signal indicative of accepting or rejecting the member based on said analysis, the method further including the wave-energizable identification apparatus and producing an identification signal received by the sensing apparatus, the sensing apparatus producing a corresponding signal indicative of identification of the member and conveying the corresponding signal to the computer apparatus, and the computer apparatus analyzing the corresponding signal and producing the analysis signal; wherein the computer apparatus conveys the analysis signal to handling apparatus for handling the member, the handling apparatus operable to accept or reject the member based on the analysis signal; wherein the member is a tubular member for use in well operations and the handling apparatus is a tubular member handling apparatus; wherein the tubular member handling apparatus is from the group consisting of tubular manipulator, tubular rotator, top drive, tong, spinner, downhole motor, elevator, spider, powered mouse hole, and pipe handler; wherein the handling apparatus has handling sensing apparatus thereon for sensing a signal from the wave-energizable identification apparatus, and wherein the handling apparatus includes communication apparatus in communication with computer apparatus, the method further including sending a handling signal from the communication apparatus to the computer apparatus corresponding to the signal produced by the wave-energizable identification apparatus; wherein the computer apparatus controls the handling apparatus; wherein the member is a tubular member and wherein the sensing apparatus is connected to and in communication with a tubular inspection system, the method further including conveying a secondary signal from the sensing apparatus to the tubular inspection system, the secondary signal corresponding to the signal produced by the wave-energizable identification apparatus; and/or wherein the signal produced by the wave-energizable identification apparatus identifies the tubular member. The present invention, therefore, in at least certain aspects, provides a method for handling drill pipe on a drilling rig, the drill pipe comprising a plurality of pieces of drill pipe, each piece of drill pipe comprising a body with an externally threaded pin end spaced-apart from an internally threaded box end, the body having a flow channel therethrough from the pin end to the box end, radio frequency identification apparatus with integrated circuit apparatus and antenna apparatus within the pin end of the body, and the antenna apparatus encircling the pin end, the method including energizing the radio frequency identification apparatus by directing energizing energy to the antenna apparatus, the radio frequency identification apparatus upon being energized producing a signal, positioning each piece of drill pipe adjacent sensing apparatus, and sensing with the sensing apparatus a signal produced by each piece of drill pipe's radio frequency identification apparatus. Such a method may include one or some (in any possible combination) of the following: wherein the sensing apparatus is in communication and is controlled by computer apparatus and wherein the radio frequency identification apparatus produces an identification signal receivable by the sensing apparatus, and wherein the sensing apparatus produces a corresponding signal indicative of the identification of the particular piece of drill pipe, the corresponding signal conveyable from the sensing apparatus to the computer apparatus, the method further including controlling the sensing apparatus with the computer apparatus; wherein the energizing is effected by energizing apparatus in communication with and controlled by computer apparatus, the method further including controlling the energizing apparatus with the computer apparatus; wherein the signal is an identification signal identifying the particular piece of drill pipe and the sensing apparatus conveys a corresponding signal to computer apparatus, the computer apparatus including a programmable portion programmed to receive and analyze the corresponding signal; and/or the computer apparatus for producing an analysis signal indicative of accepting or rejecting the particular piece of drill pipe based on said analysis, the method further including the computer apparatus analyzing the corresponding signal and producing the analysis signal, and the computer apparatus conveying the analysis signal to handling apparatus for handling the member, the handling apparatus operable to accept or reject the member based on the analysis signal. The present invention, therefore, in at least certain aspects, provides a system for handling a tubular member, the system including handling apparatus, and a tubular member in contact with the handling apparatus, the tubular member with a body with a first end spaced-apart from a second end, the first end being a pin end having a pin end recess in the first end and identification apparatus in the pin end recess, and a protector in the pin end recess protecting the identification apparatus therein; and such a system wherein the handling apparatus is from the group consisting of tubular manipulator, tubular rotator, top drive, tong, spinner, downhole motor, elevator, spider, powered mouse hole, and pipe handler. The present invention, therefore, in at least certain aspects, provides a ring with a body with a central hole therethrough, the body having a generally circular shape, the body sized and configured for receipt within a circular recess in an end of a generally cylindrical member having a circumference, wave-energizable identification apparatus within the body, the wave-energizable identification apparatus having antenna apparatus, and the antenna apparatus extending around a portion of the body; and such a ring with sensible indicia on or in the body. The present invention, therefore, in at least certain aspects, provides a ring with a body with a central hole therethrough, the body having a central hole therethrough the body sized and configured for receipt within a circular recess in an end of a generally cylindrical member having a circumference, identification apparatus within or on the body, and the identification apparatus being sensible indicia. The present invention, therefore, in at least certain aspects, provides a method for making a tubular member, the method including making a body for a tubular member, the body having a first end spaced-apart from a second end, and forming a recess around the end of the body, the recess sized and shaped for receipt therein of wave-energizable identification apparatus. Such a method may include one or some (in any possible combination) of the following: installing wave-energizable identification apparatus in the recess; installing a protector in the recess over the wave-energizable identification apparatus; and/or wherein the tubular member is a piece of drill pipe with an externally threaded pin end spaced-apart from an internally threaded box end, the recess is a recess encircling the pin end, and the wave-energizable identification apparatus has antenna apparatus, the method further including positioning the antenna apparatus around and within the pin end recess. The present invention, therefore, in at least certain aspects, provides a method for enhancing a tubular member, the tubular member having a generally cylindrical body with a first end spaced-apart from a second end, the method including forming a circular recess in an end of the tubular member, the recess sized and shaped for receipt therein of wave-energizable identification apparatus, the wave-energizable identification apparatus including antenna apparatus with antenna apparatus positionable around the circular recess. The present invention, therefore, provides, in at least some embodiments, a member with a body, the body having two spaced-apart ends, wave-energizable identification apparatus on the exterior of the body, and encasement structure encasing the wave-energizable identification apparatus, Such a member may have one or some, in any possible combination, of the following: the encasement structure is at least one layer of heat resistant material; wherein the encasement structure is at least one layer of impact resistant material; wherein the wave-energizable identification apparatus is radio frequency identification apparatus with integrated circuit apparatus and antenna apparatus; the body has a first end spaced-apart from a second end, and at least a portion comprising a generally cylindrical portion, the generally cylindrical portion having a circumference, and the radio frequency identification apparatus positioned exteriorly on the circumference of the body; wherein the body is a pipe; wherein the pipe is a tool joint with an upset portion and the wave-energizable identification apparatus is adjacent said upset portion; wherein the body has a generally cylindrical portion which is part of an item from the group consisting of pipe, drill pipe, casing, drill bit, tubing, stabilizer, centralizer, cementing plug, buoyant tubular, thread protector, downhole motor, whipstock, mill, and torus; and/or wherein the wave-energizable identification apparatus comprises a plurality of radio frequency identification tag devices. The present invention, therefore, provides in at least some, although not necessarily all, embodiments a method for sensing a wave-energizable identification apparatus of a member, the member as any disclosed herein with a body having two spaced-apart ends and wave-energizable identification apparatus on the body, and encasement structure encasing the wave-energizable identification apparatus, the encasement structure having at least one layer of heat resistant material, the wave-energizable identification apparatus with antenna apparatus on the body, the method including energizing the wave-energizable identification apparatus by directing energizing energy to the antenna apparatus, the wave-energizable identification apparatus upon being energized producing a signal, positioning the member adjacent sensing apparatus, and sensing with the sensing apparatus the signal produced by the wave-energizable identification apparatus. Such a method may have one or some, in any possible combination, of the following: wherein the sensing apparatus is on an item from the group consisting of rig, elevator, spider, derrick, tubular handler, tubular manipulator, tubular rotator, top drive, mouse hole, powered mouse hole, or floor; wherein the sensing apparatus is in communication with and is controlled by computer apparatus, the method including controlling the sensing apparatus with the computer apparatus; wherein the energizing is effected by energizing apparatus in communication with and controlled by computer apparatus, the method including controlling the energizing apparatus with the computer apparatus; wherein the signal is an identification signal identifying the member and the sensing apparatus produces and conveys a corresponding signal to computer apparatus, the computer apparatus including a programmable portion programmed to receive and analyze the corresponding signal, and the computer apparatus for producing an analysis signal indicative of accepting or rejecting the member based on said analysis, the method further including the wave-energizable identification apparatus producing an identification signal received by the sensing apparatus, the sensing apparatus producing a corresponding signal indicative of identification of the member and conveying the corresponding signal to the computer apparatus, and the computer apparatus analyzing the corresponding signal and producing the analysis signal; wherein the computer apparatus conveys the analysis signal to handling apparatus for handling the member, the handling apparatus operable to accept or reject the member based on the analysis signal; wherein the member is a tubular member for use in well operations and the handling apparatus is a tubular member handling apparatus; wherein the tubular member handling apparatus is from the group consisting of tubular manipulator, tubular rotator, top drive, tong, spinner, downhole motor, elevator, spider, powered mouse hole, and pipe handler; wherein the handling apparatus has handling sensing apparatus thereon for sensing a signal from the wave-energizable identification apparatus, and wherein the handling apparatus includes communication apparatus in communication with computer apparatus, the method including sending a handling signal from the communication apparatus to the computer apparatus corresponding to the signal produced by the wave-energizable identification apparatus; wherein the computer apparatus controls the handling apparatus; wherein the member is a tubular member and wherein the sensing apparatus is connected to and in communication with a tubular inspection system, the method including conveying a secondary signal from the sensing apparatus to the tubular inspection system, the secondary signal corresponding to the signal produced by the wave-energizable identification apparatus; and/or wherein the signal produced by the wave-energizable identification apparatus identifies the tubular member. The present invention, therefore, provides in at least certain, if not all, embodiments a method for handling drill pipe on a drilling rig, the drill pipe comprising a plurality of pieces of drill pipe, each piece of drill pipe being a body with an externally threaded pin end spaced-apart from an internally threaded box end, the body having a flow channel therethrough from the pin end to the box end, radio frequency identification apparatus with integrated circuit apparatus and antenna apparatus on the body, and encased in heat resistant material, the method including energizing the radio frequency identification apparatus by directing energizing energy to the antenna apparatus, the radio frequency identification apparatus upon being energized producing a signal, positioning each piece of drill pipe adjacent sensing apparatus, and sensing with the sensing apparatus a signal produced by each piece of drill pipe's radio frequency identification apparatus. Such a method may include, wherein the sensing apparatus is in communication and is controlled by computer apparatus and wherein the radio frequency identification apparatus produces an identification signal receivable by the sensing apparatus, and wherein the sensing apparatus produces a corresponding signal indicative of the identification of the particular piece of drill pipe, said corresponding signal conveyable from the sensing apparatus to the computer apparatus, controlling the sensing apparatus with the computer apparatus, and wherein the energizing is effected by energizing apparatus in communication with and controlled by computer apparatus, controlling the energizing apparatus with the computer apparatus, and wherein the signal is an identification signal identifying the particular piece of drill pipe and the sensing apparatus conveys a corresponding signal to computer apparatus, the computer apparatus including a programmable portion programmed to receive and analyze the corresponding signal, the computer apparatus for producing an analysis signal indicative of accepting or rejecting the particular piece of drill pipe based on said analysis, the computer apparatus analyzing the corresponding signal and producing the analysis signal, and the computer apparatus conveying the analysis signal to handling apparatus for handling the member, the handling apparatus operable to accept or reject the member based on the analysis signal. The present invention, therefore, in at least certain aspects, provides a tool joint with a body having a pin end spaced-apart from a tube body, an upset portion, a tool joint portion between the upset portion and the pin end, and wave-energizable identification apparatus on the tube body adjacent the upset portion, the wave-energizable identification apparatus encased in heat resistant material. FIG. 31 illustrates a system 800 according to the present invention which has an offshore drilling and/or production system 821 including a drilling conductor or riser 823 extending between subsea well equipment 825 , and a floating rig, ship, or vessel, such as, for example, a dynamically positionable vessel 827 . The drilling riser pipe or conductor 823 has multiple riser sections 829 connected together by joints 831 and extending between a sea bottom S and the vessel 827 . A tensioning system 833 located on an operational platform 835 of the vessel 827 provides both lateral load resistance and vertical tension preferably applied to a slip or tensioning ring 839 attached to the top of the riser 823 and below a telescopic joint 841 . The telescopic joint 841 decouples the vessel 827 and riser 823 from vertical motions. The riser 823 is further connected at its distal end to a lower marine riser package (“LMRP”) 843 . The LMRP 843 is releasably yet rigidly connected to a blowout preventer (“BOP”) 845 . The BOP 845 is fixedly connected to the upper section of a wellhead 849 . The lower section of the wellhead 849 connects to a wellhead conductor 851 which extends downwardly through the subsea floor S. Each riser section 829 has an identification assembly 810 according to the present invention with wave-energizable identification apparatus. Some or all but one of the assemblies 810 may be deleted. A lowermost riser section 829 a has two assemblies 810 (as may be true for any riser or riser section in FIG. 31 and for any riser or riser section disclosed herein). The apparatuses 810 may be any identification apparatus disclosed herein according to the present invention. FIG. 32A shows a riser 860 according to the present invention with three sections 860 a , 860 b and 860 c with clamp sets 862 , a top flange 863 , a bottom flange 864 , a choke line 865 a and a kill line 865 b (the lines held by the clamp sets 862 ). The lowermost section 860 c has an identification assembly 870 according to the present invention around the tubular circumference of the riser section. Optionally, the sections 860 a and 860 b have wave-energizable identification apparatuses 871 which are like any wave-energizable identification apparatus disclosed herein. Optionally, straps 869 secure the apparatus 870 to the riser section 860 c . These straps may be made of any suitable material, e.g., but not limited to, metal (e.g. steel), fiberglass, plastic (e.g. nylon), or composite material. In one particular aspect the straps are SMART BAND™ flexible bands commercially available from HCL Fasteners UK. FIG. 33A shows the identification apparatus 870 which has a body 872 with an interior surface 874 and an exterior surface 876 . In one aspect, the body 872 is a single integral piece, e.g. a molded plastic part. In one aspect, (in FIGS. 33C and 33D ) the body 872 has two ends 878 a and 878 b which, initially, are spaced-apart to facilitate emplacement of the body 872 around a riser. Upon installation on a riser, the ends 878 a , 878 b are brought together and connected together, e.g. with any known connection material or structure, e.g., but not limited to, with adhesive 873 or, optionally, a screw (or screws) 879 a and/or, optionally, amounts of selectively connectable releasably cooperating fastener material 877 a connected to the end 878 a and amount 877 b connected to the end 878 b . In one aspect, as shown, the releasably cooperating fastener material overlaps and seals off a junction 875 . Optionally spaces 871 a , 871 b are provided between parts of the ends 878 a , 878 b (which as shown are stepped ends) so that a single body 872 can accommodate risers of different outer diameter; e.g., but not limited to, risers of both twenty-one inch outer diameter and of twenty-one and a half inch outer diameter. Optionally, the body 872 has a recess or recesses 889 for receiving and positioning a strap or straps (e.g. straps 869 to secure the body 872 around a riser. Optionally, the body 872 has one, two or more projections 882 connected thereto or, as shown in FIGS. 33A, 33B , and 33 E, formed integrally thereof. In one aspect the projection(s) are located to direct impact loads away from assemblies 890 and to absorb a force or load applied to the body adjacent a wave-energizable identifier (e.g. a tag) or identifiers embedded in the body 872 , e.g. the assemblies 890 . As shown in FIG. 33B , a recess 887 with tapered sides 887 a between the two projections 882 directs or focuses to the assemblies 890 energy transmitted to the assemblies 890 . FIGS. 40A-40B , discussed below, show various shapes and configurations for a body like the body 872 . It is within the scope of the present invention to use one, two, three, four, five, six or more identification assemblies 890 in the body 872 or in any body of any assembly according to the present invention. In one particular aspect the assemblies 890 are about six inches in length. The assemblies 890 (any identification wave-energizable tag disclosed or referred to herein) are surrounded by the body 872 . In one particular aspect, the body 872 is made of flexible polyurethane foam and is held on a riser with high tensile strength steel straps or with flexible nylon straps. It is within the scope of the present invention for the tag assembly 890 to include a shield around a wave-energizable apparatus, e.g. as disclosed in co-pending U.S. application Ser. No. 12/317,246 filed Dec. 20, 2008, co-owned with the present invention and fully incorporated herein for all purposes. For example, a tag 890 a with a wave-energizable apparatus 890 b may be shielded by a shield 912 with the tag 890 a in a recess 922 of the shield 912 (as shown in FIG. 34A ). In one aspect a shield 912 is made of plastic, e.g. polyoxymethylene (e.g., in one particular aspect, Dupont DELRIN™ material). The recess 922 can be machined into the material. In one aspect, as shown in FIG. 34D , a wave-energizable assembly 890 c is placed in a recess 922 of a shield 912 and then the shield apparatus combination is inserted into or wrapped with a tube 924 , e.g. a tube of shrink wrap material. The resulting structure is then placed on and/or taped to a riser or embedded in a body, like the body 872 . In one aspect, the shield with the assembly is wrapped with heat shrink material which encompasses a riser. In one aspect any material described herein is used for the tube and for the wrap. In one aspect crosslinked polyethylene shrink wrap material (or “XLPE”) is used. Heat is applied to the material which heats and shrinks and the is allowed to cool. One, two or more additional wrap layers can be applied. In one aspect the shield with the wave-energizable apparatus is set on a riser or a body like the body 872 and material is wrapped around the shield to connect the shield and its wave-energizable apparatus riser or the body. A shield (like the shield 912 ) according to the present invention can be of any desired cross-sectional shape and a wave-energizable apparatus can be of any desired cross-sectional shape (or encasing material around such an apparatus can be of any desired shape). FIG. 35 illustrates shields 912 a , 912 b , 912 c , 912 d and 912 e of different cross-sectional shapes with wave-energizable apparatuses, respectively, 910 a , 910 b , 910 c , 910 d , 910 e , and 910 f of different cross-sections. One shield may house multiple wave-energizable apparatuses. FIG. 36 shows shields 912 f , 912 g , 912 h and 912 i with, respectively, recesses 922 f , 922 g , 922 h and 922 i for housing a wave-energizable apparatus. A wave-energizable apparatus may be held in a shield recess by a friction-fit and/or with adhesive. Optionally a shield recess may have holding lips like the lips 9221 of the shield 912 h and the lips 922 m of the shield 912 i. According to the present invention an energizable identification apparatus can be applied to, connected to, or disposed on a member using a solid mass within which is located the energizable identification apparatus (e.g., but not limited to, a mass as disclosed in pending U.S. application Ser. No. 12/317,246 filed Dec. 20, 2008). FIG. 37 shows a mass 951 of material within which is an energizable identification apparatus 959 . The mass 951 (and the masses 1141 and 1151 ) is sized and configured for insertion into a recess, notch, hollow, space, channel or opening of a riser or riser section, or it can be connected and/or strapped thereon. The mass 951 can be held in place with a friction fit and/or adhesive, glue, welding, and/or tape and/or with a body like the body 872 . The material of the mass 951 (and the masses 1141 and 1151 ) can be metal, plastic, composite, wood, ceramic, cermet, gel, aerogel, silica aerogel, fiberglass, nonmagnetic metal, or polytetrafluoroethylene. The material can be rigid and relatively unbending or it can be soft and/or flexible. An enlarged end 951 a of the mass 951 is optional. FIG. 38 shows a mass 1151 (made, e.g. of any material mentioned for the mass 951 ) with an energizable identification apparatus 1159 therein. The energizable identification apparatus 1159 has an antenna 1158 extending from the energizable identification apparatus 1159 and disposed within the mass 1551 . With a flexible or sufficiently non-rigid mass 1151 (and with the mass 951 ) a slit or recess 1157 of any desired length within the mass 1151 may be provided for inserting the energizable identification apparatus 1159 and antenna 1158 into the mass 1151 and/or for removable emplacement of the energizable identification apparatus 1159 . FIG. 39 shows a mass 1141 (e.g. like the masses 951 , 1151 and made of the materials mentioned above) with an energizable identification apparatus 1142 therein (or it may, according to the present invention, be thereon). The mass 1141 has a recess 1143 sized, located, and configured for receipt therein of a part or a portion of a riser, riser section or body like the body 872 to facilitate installation of the mass 1141 . A friction fit between the mass 1141 and a part or portion can hold the mass 1141 in place and/or connectors, fasteners and/or adhesive may be used to hold the mass 1141 in place. FIG. 40A shows a riser identification assembly 1160 according to the present invention (like the assembly 870 in general shape and configuration as shown in FIG. 33A ) with a body 1162 having a projection 1163 . The projection 1163 has two spaced-apart recesses 1164 for receiving and holding straps (like the straps 869 ). A portion 1163 a of the projection 1163 is over (as viewed in FIG. 40A ) a wave-energizable apparatus 1165 . The recesses 1164 are located so that they are not over the apparatus 1165 . FIG. 40B shows a riser identification assembly 1170 (like the assembly 870 in general shape and configuration as shown in FIG. 33A ) with a body 1172 having a projection 1173 partially over a wave-energizable apparatus 1175 . A strap 1176 resides partially in a recess 1174 over the apparatus 1175 . In one aspect according to the present invention the strap 1176 does not project beyond an exterior surface of the projection (as may any strap herein be sized and located). In another aspect, as shown in FIG. 40B , the strap 1176 (as may any strap herein project beyond a recess and/or a surface) projects beyond an exterior surface of the projection 1173 . In one aspect the strap 1176 is wider than the apparatus 1175 . FIG. 40C shows a riser identification assembly 1180 with a body 1182 having two strap recesses 1184 and a projection 1186 . The projection 1186 may be, as shown, wider than a wave-energizable apparatus 1185 within a shield 1187 (any shield disclosed herein may be used). Any wave-energizable apparatus used with any riser identification assembly according to the present invention may contain information (to include information and/or data) which includes some or all of: riser identification; design data for the riser; history of use of the riser; metallurgy of the riser; installation procedures; test information; quality control information; and/or manufacturing process information. Such information is conveyable to: a control system or control systems, all personnel, including, but not limited to, rig operator(s), controller(s) on site and/or off site, and/or driller(s), on-site and/or off-site. When a riser with one or more identification assemblies is removed from a location of installation, the wave energizable apparatus or apparatuses is (are) scanned and personnel and/or a control system and/or connected systems are notified of the removal and any pertinent data regarding the removal and/or the use can be entered into the wave-energizable apparatus or apparatuses). A control system (e.g. the driller system and/or a remote system) can then automatically request any required user actions and/or inputs (e.g. actions: photograph the riser, clean the riser, photograph the riser again; e.g. inputs: visual observations of the riser, producing a description (written, oral, etc.) of the used riser, and/or comments describing key aspects of the riser use and/or removal). Actual data and information from the use can be recorded automatically (e.g., in a driller system and/or a control system) and recorded into the wave-energizable apparatus or apparatuses. Any, some, or all such data can be recorded in any wave-energizable apparatus associated with a riser. The present invention, therefore, provides in at least certain, if not all, embodiments a member with a body, the body having an exterior surface and two spaced-apart ends, wave energizable identification apparatus on the exterior surface of the body, the wave energizable identification apparatus wrapped in fabric material, the fabric material comprising heat-resistant non-conducting material, the wave energizable identification apparatus wrapped and positioned on the body so that the wave energizable identification apparatus does not contact the body, and the member is a riser. Such a method may have one or some, in any possible combination, of the following: the fabric material is at least one layer of material wrapped around the wave energizable identification apparatus; the wave energizable identification apparatus and the fabric material in which the wave energizable identification apparatus are wrapped is heat shrink material; and/or wherein the wave energizable identification apparatus is radio frequency identification apparatus with integrated circuit apparatus and antenna apparatus. The present invention, therefore, provides in at least certain, if not all, embodiments a riser including: a riser body having an interior surface, an exterior surface, and two spaced-apart ends; at least one identification assembly (or a plurality) on the riser body; the identification assembly having an assembly body and a wave energizable apparatus in the body; the assembly body having an interior surface, an exterior surface, and a channel therethrough in which is positioned part of the riser body; the assembly body releasably secured on the riser body; and the wave energizable apparatus positioned within the assembly body. Such a method may have one or some, in any possible combination, of the following: wherein the assembly body has two ends, the two ends connected together; wherein the two ends of the assembly body are connected together by one of adhesive, fastener, and releasably cooperating fastener material; wherein the assembly body has at least one recess (or at least two or two) for a strap; wherein a strap is within the at least one recess, the strap securing the identification assembly to the riser body; wherein the assembly body has at least one projection projecting therefrom; wherein the wave-energizable apparatus is shielded by a shield within the assembly body; wherein the at least one projection is a first projection positioned over the wave-energizable apparatus; wherein a strap is within the at least one recess, the strap securing the identification assembly to the riser body and wherein the strap has a portion that projects out of the at least one recess over the wave-energizable apparatus; a recess in the assembly body adjacent the identification assembly for direction energy for energizing the wave-energizable apparatus to the wave-energizable apparatus; wherein the wave-energizable apparatus includes information regarding the riser; and/or wherein the information includes information regarding at least one of (or some of, or all of): riser design information, riser identity information, riser use information, riser installation information, riser test information, riser quality control information, riser observation information; The present invention, therefore, provides in at least certain, if not all, embodiments a riser with a riser body having an interior surface, an exterior surface, and two spaced-apart ends; a plurality of identification assemblies on the riser body; each of the plurality of identification assemblies having an assembly body and a plurality of wave energizable apparatuses in the body; each assembly body having an interior surface, an exterior surface, and a channel therethrough in which is positioned part of the riser body; each assembly body releasably secured on the riser body; each wave energizable apparatus positioned within an assembly body; each assembly body having two ends, the two ends connected together; the two ends of each assembly body connected together by one of adhesive, fastener, and releasably cooperating fastener material; each assembly body having at least one recess for a strap; a strap within the at least one recess, the strap securing the identification assembly to the riser body; and each assembly body having at least one projection projecting therefrom. The present invention, therefore, provides in at least certain, if not all, embodiments a riser identification assembly for securement to a riser, the riser having a riser body around which the riser identification assembly is securable, the riser identification assembly including: an assembly body securable around a riser, and a wave-energizable apparatus within the assembly body, the wave energizable apparatus including information about the riser; and, in some aspects, wherein the assembly body has two ends, the two ends connected together by one of adhesive, fastener, and releasably cooperating fastener material, and wherein the assembly body has at least one recess for a strap forcing the riser identification assembly to a riser. The present invention, therefore, provides in at least certain, if not all, embodiments a method for identifying a riser, the riser having a riser body, the method including: activating a wave-energizable apparatus that is releasably secured within an identification assembly, the identification assembly secured around the riser body; and reading identity information from the wave-energizable apparatus to identify the riser. In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to the step literally and/or to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form it may be utilized. The invention claimed herein is new and novel in accordance with 35 U.S.C. §102 and satisfies the conditions for patentability in §102. The invention claimed herein is not obvious in accordance with 35 U.S.C. §103 and satisfies the conditions for patentability in §103. This specification and the claims that follow are in accordance with all of the requirements of 35 U.S.C. §112. The inventors may rely on the Doctrine of Equivalents to determine and assess the scope of their invention and of the claims that follow as they may pertain to apparatus not materially departing from, but outside of, the literal scope of the invention as set forth in the following claims. All patents and applications identified herein are incorporated fully herein for all purposes. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function. In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.

A riser having a riser body having an interior surface, an exterior surface, and two spaced-apart ends, at least one identification assembly on the riser body, the identification assembly having an assembly body and a wave energizable apparatus in the body, the assembly body having an interior surface, an exterior surface, and a channel therethrough in which is positioned part of the riser body, the assembly body releasably secured on the riser body, and the wave energizable apparatus positioned within the assembly body. This abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims, 37 C.F.R. 1.72(b).

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is related to the field of electric wireline tools used to withdraw samples of fluids contained within pore spaces of earth formations. More specifically, the present invention is related to systems for determining various fluid flow properties of earth formations by using a formation testing apparatus having a plurality of fluid sampling probes which are radially and axially spaced apart and hydraulically isolated from each other. 2. Description of the Related Art Electric wireline formation testing tools are used to withdraw samples of fluids and to make pressure measurements of fluids contained within pore spaces of earth formations. Calculations made from these measurements can be used to assist in estimating the total fluid content within the earth formations. Formation testing tools known in the art are typically lowered at one end of an armored electrical cable into a wellbore drilled through the earth formations. The formation testing tools known in the art can include a tubular probe which is extended from the tool housing and is then impressed onto the wall of the wellbore. The probe typically is externally sealed by an elastomeric packing element to exclude fluids from within the wellbore itself from entering the interior of the probe as fluids are withdrawn from the earth formation through the probe. Various valves selectively place the probe in hydraulic communication with sample chambers included in the tool. The probe can also be connected to a highly accurate pressure sensor which measures the fluid pressure at or near the probe. Other sensors in the tool can make measurements related to the volume of fluid which has entered the sample chambers during a test of a particular earth formation. The formation testing tools known in the art can also include a sample tank. The sample tank can be selectively connected to the probe so that a quantity of fluid withdrawn from the formation can be discharged into the sample tank and transported to the earth's surface for laboratory analysis. Other formation testing tools known in the an can include more than one probe. For example, one formation testing tool known in the art includes two collinear probes positioned at axially spaced-apart locations along the tool. By providing two probes at axially spaced apart locations, it is sometimes possible to determine to what extent a particular earth formation has permeability coaxial with the wellbore. Typically, one of the two probes in the two-probe tool is used to withdraw fluid from the formation while monitoring fluid pressure at the tither probe. The time elapsed between withdrawal of the fluid at the one probe and indication of pressure drop at the other probe can be indicative of the coaxial permeability of the earth formation. A drawback to the two-probe tool known in the art is that it is unable to resolve permeability discontinuities which may cross the wellbore at certain oblique angles. Using the two-probe tool known in the art, it is possible that coaxial permeability discontinuities which may be observed with the tool in one rotary orientation within the wellbore may not be observed in other rotary orientations, which allows the possibility that coaxial permeability discontinuities of significant interest to the wellbore operator could go undetected. It is also known in the art to provide a formation testing tool having two probes opposingly faced and located at substantially the same axial position along the tool in addition to the axially spaced apart collinear probes. The opposingly faced probes can observe some permeability discontinuities intersecting the wellbore obliquely which may be missed by the axially-spaced apart probes. Such a tool is described for example in U.S. Pat. No. 5,335,542 issued to Ramakrishnan et al. A drawback to the tool in the Ramakrishnan '542 patent having opposingly faced probes is that this tool may provide insufficient radial resolution to observe permeability discontinuities which may traverse the wellbore in such a way as to make the apparent permeability substantially equal as observed by either opposing probe relative to the axially spaced-apart probe. A still further drawback to the formation testing tools known in the art is that the probes used to withdraw fluid samples typically have small cross-sectional areas relative to the surface area of the wellbore. Some features of earth formations which can be highly productive of oil and gas may intersect only a very small portion of the surface area of the wellbore and there wellbore have a high probability of being missed by one of the probes on the formation testing tools known in the art. Such features can include fractures or thin layers of permeable sandstone interleaved with impermeable strata such as shale. It is known in the an to provide a means for isolating a substantial axial section of the wellbore so that the entire surface area of the wellbore within the section can be exposed to fluid withdrawal by a formation testing tool. Axial sections can be isolated by providing a device known as a straddle packer. The straddle packer known in the an includes two inflatable elastomeric bladders positioned at axially-spaced apart locations along the tool. A port is provided on the tool at an axial position in between the bladders. The port can be selectively hydraulically connected to the various sample chambers of the formation testing tool. As it is typically used, the straddle packer is positioned within a zone of interest, the bladders are inflated to hydraulically isolate the zone and fluid is withdrawn through the port by various pumping and flow control devices in the tool. A drawback to the straddle packer is that the bladders can only isolate the zone of interest axially. The straddle packer is unable to provide measurements determining permeability coaxial with the wellbore or for determining the presence of coaxial permeability discontinuities intersecting the wellbore. Further, the large volume which is isolated between the bladders results in a large volume of fluid that must be withdrawn from the axial section bladder native fluid from the formation enters the testing tool. Withdrawing a large fluid volume can require leaving the tool in place for a long time. Leaving the tool in place for a long time can be unsafe and expensive. Further, the capacity of the fluid pumps in formation testing tools known in the art is limited. It can be difficult to determine the permeability of highly permeable formations using the straddle packer tool known in the art, because the large surface area of the wellbore which is exposed to fluid withdrawal can provide a high volume of fluid relative to the volume that the pump is capable of withdrawing. If the formation can produce fluid faster than the fluid can be pumped away, then substantially no pressure drop will occur. To determine permeability requires at least some amount of pressure drop from the earth formation's original pressure to be measured. It is an object of the present invention to provide an electric wireline formation testing tool which can provide improved radial resolution of permeability discontinuities intersecting the wellbore. It is a further object of the present invention to provide a formation testing tool which can withdraw fluid from permeable features intersecting the wellbore which have a small surface area, while reducing the volume of fluid tram within the wellbore which must be pumped away before sampling of the native fluid can begin. It is yet a further object of the present invention to provide a formation testing tool which can withdraw fluid from permeable features intersecting the wellbore which have a small surface area, while maintaining the ability to determine permeability of the formation even if the permeability is very high. SUMMARY OF THE INVENTION The present invention is an apparatus for withdrawing fluid from an earth formation penetrated by a wellbore. The apparatus includes an elongated housing and a first inflatable elastomeric seal disposed on the housing and adapted to expansively fill an annular space between the housing and the wellbore. The apparatus further includes means for selectively inflating the seal. The seal includes axially spaced apart seal lips protruding from an exterior surface of the seal. The seal lips circumscribe the seal and define a flow channel between them. The flow channel includes radially spaced apart filler blocks which divide the channel into radial segments. Each one of the segments further includes a flow port. The apparatus also includes valves connected to each one of the flow ports for connecting selected ones of the flow ports to an intake of a fluid pump disposed within the housing and connecting selected other ones of the flow ports to a discharge port of the pump. The pump is selectively operable in conjunction with the valves to withdraw fluid from selected ones of the flow ports and to discharge fluid into other selected ones of the flow ports. The apparatus includes a fluid discharge port connected to the valves, and in hydraulic communication with the wellbore so that fluid withdrawn from selected ones of the flow ports can be selectively discharged into the wellbore, and fluid selectively withdrawn from the wellbore can also be selectively discharged through selected ones of the flow ports. The apparatus also includes a pressure transducer connected to the pump intake so that a pressure of the fluid withdrawn by the pump can be determined. A preferred embodiment of the invention includes a second pressure transducer connected to the pump discharge and differential pressure transducers selectively interconnected between adjacent ones of the flow ports to measure radial differences in fluid pressure during fluid withdrawal from, or discharge into, the formation. A specific embodiment of the invention includes a second elastomeric seal axially spaced apart from the first seal. The second seal also includes seal lips, filler blocks and flow ports which can be selectively connected to the pump intake and discharge. The present invention is also a method of determining the presence of hydraulic discontinuities in an earth formation penetrated by a wellbore. The method comprises the steps of positioning a formation testing tool in the wellbore adjacent to the earth formation and hydraulically isolating a first and second portions of the earth formation by expanding, respectively, a first seal and a second seal against the wall of the wellbore. The first and second seal include radial flow isolators for hydraulically isolating radial segments of the first and second portions of the wall of the wellbore. The method includes operating valves and a pump disposed in the testing tool to selectively withdraw fluid from the first portion, measuring fluid pressure at each one of the radial segments of the second portion, and determining the presence of discontinuities from differences in pressure between the radial segments of the second portion. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a formation test tool according to the present invention being lowered into a wellbore penetrating earth formations. FIG. 2 shows an expanded view of an inflatable bladder seal having four radially separated snorkels. FIG. 3 shows a cross-section of the inflatable bladder seal in its retracted state and expanded to contact the wall of the wellbore. FIG. 4A shows hydraulic control valves for operating the connection of each one of the ports in a formation testing tool including two of the inflatable bladder seals. Connections are selectively made to the intake of a pump. FIG. 4B shows selective connections to the discharge side of the pump. DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows a formation testing tool 10 according to the present invention being lowered into a wellbore 2 penetrating earth formations, shown generally at 12 and 14. The tool 10 can be lowered into the wellbore at one end of an armored electrical cable 4. The cable 4 can be extended into the wellbore by means of a winch 6 or similar device known in the art. The cable 4 is electrically connected to a surface electronics unit 8 which can include a computer (not shown) for receiving and interpreting signals transmitted by the tool 10, as will be further explained. The tool 10 includes an electronics section 16 which can receive and interpret command signals transmitted from the surface electronics 8 in response to the system operator entering commands therein, as will be further explained. The commands are entered for, among other things, selectively operating various hydraulic valves in the tool 10 to direct flow of fluids as desired by the system operator, as will also be further explained. The tool 10 can include a first 18 and a second 20 inflatable bladder seal section. The first 18 and second 20 inflatable bladder seal sections are attached to a hydraulic power unit 10A used to selectively inflate each seal section, which will be further explained. The first 18 and second 20 bladder seal sections can be axially spaced apart by a distance which is related to the expected vertical permeability, as is understood by those skilled in the art. The selected axial spacing of the first 18 and the second 20 bladder seal sections is a matter of convenience for the system operator and is not to be construed as a limitation on the invention. Operation of the bladder seal sections 18.20 will be further explained. The tool can also include a sample tank 22. As will be further explained, fluids withdrawn from the earth formations 12, 14 can be discharged into the tank 22 upon control of the appropriate valves (not shown in FIG. 1) upon entry of the appropriate command by the system operator. Fluids thus discharged into the tank 22 can be transported to the earth's surface for laboratory analysis. Other fluids (not shown) can be transported from the earth's surface into the wellbore by the sample tank 22 for selectively discharging the other fluids into the earth formations 12, 14 for certain types of tests known in the art such as injectivity testing. FIG. 2 shows the first inflatable bladder seal section 18 in more detail. The first seal section 18 includes a reinforced elastomeric bladder 26. The reinforcement is formed into the elastomeric material and can be of a type known in the art such as steel wire or glass fiber. The bladder 26 can be inflated by pumping fluid from the wellbore (shown as 2 in FIG. 1) into the interior of the bladder 26. The pumping can be performed by a reversible, electrically powered fluid pump, shown generally at 24. The pump 24 can be hydraulically connected on one side to the wellbore 2 by a first port 28 and hydraulically connected on its other side to the interior of the bladder 26 by a second port 30. Alternatively, the bladder 26 can be inflated by a fluid, such as hydraulic oil, which can be transported within the tool 10 in a separate reservoir (not shown). The bladder 26 can be sealed between its interior and exterior, and substantially immovably mounted on one end by a seal ring 50. The opposite end of the bladder 215, as shown at 52, can be mounted on a portion of the tool 10, shown at 54, which forms a sealing surface for the other end of the bladder 26, so that the end 52 can slidably move while maintaining an hydraulic seal between the interior and exterior of the bladder 26. Hydraulic sealing of the slidably mounted end 52 of the bladder 26 can be performed by o-rings, shown at 56. As fluid is pumped into the bladder 26, its outside diameter typically expands, and the slidably mounted end 52 is typically withdrawn towards the fixed end (mounted at ring 50) as is understood by those skilled in the art. Reversing the pump 24 enables the system operator to selectively deflate the bladder 26 so that its external diameter shrinks, enabling the tool (10 in FIG. 1) to be moved within the wellbore (2 in FIG. 1). The bladder 26 of the present invention includes an upper seal lip 32, and a lower seal lip 34 axially spaced apart from the upper seal lip 32. Both seal lips 32, 34 can be integrally formed into the surface of the elastomeric material which forms the bladder 26. Both seal lips 32, 34 circumscribe the bladder 26, in a plane substantially perpendicular to the axis of the bladder 26. Both seal lips 32, 34 can be internally reinforced with a substantially incompressible material, such as steel or glass-fiber reinforced plastic, which will maintain the general profile of the seal lips 32, 34, but will also enable sufficient compression of the seal lips 32, 34 to seal against the wellbore (2 in FIG. 1) wall when the bladder 26 is expanded. In the preferred embodiment of the invention, the axial spacing of the seal lips 32, 34 can be about one-half inch. The axial spacing of the seal lips 32, 34 is not to be construed as an explicit limitation on the invention. The spaced-apart seal lips 32, 34 define a flow channel therebetween, as shown at 36. The flow channel 36 can be hydraulically connected to a plurality of low ports, shown for example at 38, 40 and 42. As will be further explained, the flow ports, 38, 40, 42 can be connected, respectively, to hydraulic hoses, such as shown at 46, 48 and 44, to enable fluid from the formation (12 and 14 in FIG. 1) to move through various hydraulic lines in the tool (10 in FIG. 1) as selected by the system operator entering appropriate commands into the surface electronics (8 in FIG. 1). The flow channel 36 can be radially segmented by filler blocks, such as ones shown at 33 and 35 which substantially fill the flow channel 36 and create a flow barrier between any two of the flow ports 38, 40, 42. By radially segmenting the flow channel 36, each flow port 38, 40, 42 can be placed in hydraulic communication with a segment of the formation (12, 14 in FIG. 1) defined by the axial spacing of the seal lips 32, 34 and radially defined by the positions of the filler blocks 33, 35. In the preferred embodiment of the invention, the flow channel 36 comprises four filler blocks radially spaced apart at about 90 degrees, and the flow channel includes for hydraulically isolated flow ports. It is to be understood that other quantities of filler blocks and flow ports within the flow channel 36 of the present invention would also accomplish the intended purpose of radial segmentation of the hydraulic connection of a flow port to the earth formation. When the bladder 26 is expanded, the flow channel 36 is placed in hydraulic communication with an area of the formation (12, 14 in FIG. 1) on the wall of the wellbore 2 which is much larger than the cross-sectional area of an individual flow port (such as 38). The cross-sectional area of the radial segments is also larger than the cross-sectional area of a tubular probe typically used in formation testing tools known in the prior art, and is therefore much less likely than such probes to encounter complete impermeability at any particular position on the wellbore 2 wall when testing earth formations which include variable permeability features such as shale laminae. The enclosed volume of the flow channel 36 is still relatively small, however, when compared with the enclosed flow volume of a device known in the art called a straddle packer. The straddle packer isolates an axial section of the formation 12 or 14 by expanding two, axially spaced apart inflatable bladder seals against the wall of the wellbore 2. The axial section of the straddle packer has a volume substantially equal to the volume of a cylinder having a diameter of the wellbore and a length of the axial spacing between the seals. It is therefore possible, using the seal section 18 of the present invention, to withdraw fluids from the earth formation which might be missed by the probe of the formation testing tools known in the prior art, but the amount of fluid which must be withdrawn from the wellbore 2 itself is kept to a minimum compared with the straddle-packer testing tools known in the prior art. The seal section 18 of the present invention, by having only a small surface area of the wellbore 2 wall hydraulically connected to the sampling components in the tool 10, enables the use of fluid pumps typically included with formation testing tools known in the art to withdraw fluids from the earth formation at sufficient rates to be able to estimate formation permeability. A better understanding of the operation of the seal section 18 according to the present invention can be obtained by referring to FIG. 3, which is a cross-sectional view of the seal section 18 along section A-A' of FIG. 2. FIG. 3 shows the cross section A-A', both with the bladder 26 expanded, and with the bladder 26 deflated or retracted. The flow channel 36 is shown divided by four filler blocks 33, 35, 37, 39 into hydraulically isolated segments (not separately designated). Each segment in the flow channel 36 is further connected to one of four flow ports, 29, 38, 42 and 40. The ports are each connected, respectively, to hydraulic hoses 31, 46, 44 and 48. The expanded bladder can be observed with the flow channel at 36E, the ports at 29E, 42E, 40E and 38E and the blocks at 33E, 35E, 37E and 39E. As will be readily understood by those skilled in the art, the hydraulic hoses 31, 44, 48, 46 provide flexible coupling of the ports 29, 42, 40, 38 to hydraulic lines (which will be further explained) in the tool (10 in FIG. 1) so as to enable expansion and contraction of the bladder (26 in FIG. 2) as required by the system operator while maintaining hydraulic connection of the flow ports to valves in the tool, which will be further explained. Referring again to FIG. 1, the preferred embodiment of the tool 10 can have two seal sections, shown at 18 and 20. It is to be understood that other configurations of the tool 10 according to the present invention could include other quantities of seal sections. The quantity of seal sections is not to be construed as a limitation on the invention. Referring now to FIG. 4, the hydraulic interconnections of the flow ports (such as 38 in FIG. 2) to various selective valves in the tool will be described. Hydraulic connections to the individual flow ports, made through the previously described hoses (such as one shown at 31 in FIG. 2) are coupled to connectors 102, 104. 106 and 108 in the lower seal section (20 in FIG. 1), and are coupled to connectors 150. 152, 154 and 156 in the upper seal section (18 in FIG. 1). All of the connectors in FIG. 4 can be hose-to-line couplings of a type known in the art. Through appropriate operation of various valves, each individual flow port can be selectively hydraulically connected to one of several different terminations. The terminations can include connection to the intake of a fluid pump 164, isolation from the other ports, or can include connection to a differential pressure transducer (which will be further explained) for measurement of a pressure difference between that port and another port. For example, a port in the second seal section (20 in FIG. 1) can be isolated from the all the other ports and from the pump 164 by closing an isolation valve, such as shown at 101, 103, 105 and 107 corresponding to ports connected to connectors 102. 104, 106 and 108, respectively. Similarly, in first seal section (18 in FIG. 1), valves 142, 144, 146 and 148 can be selectively closed to isolate the ports connected, respectively, to connectors 150, 152, 154 and 156. The valves can be electrically operated solenoid valves of a type familiar to those skilled in the art. Operation of each valve can be individually controlled by the system operator entering appropriate commands into the surface electronics (8 in FIG. 1), which then transmits control signals along the cable (4 in FIG. 1. The control signals can be decoded into electrical operating signals for each valve by the electronics section (16 in FIG. 1), as is understood by those skilled in the art. Each connector can be hydraulically interconnected to an adjacent connector through a differential pressure transducer ("DPT"), such as a first DPT shown at 110 interconnecting connectors 102 and 108, a second DPT at 112 interconnecting connectors 102 and 104, a third DPT at 114 interconnecting connectors 104 and 106, and a fourth DPT interconnecting connectors 106 and 108. Similar interconnections of the connectors for the upper seal section (18 in FIG. 1) through DPT's can be observed at 134, 136, 138 and 140. The DPT's can be of a type known in the art generating an electrical signal corresponding to the difference in pressure between the inputs to the DPT. The electrical signals from each DPT can be provided to the electronics section (16 in FIG. 1) for transmission to the surface electronics (8 in FIG. 1) for decoding and interpretation, as will be readily apparent to those skilled in the art. Hydraulic connection of each one of the connectors described herein can further be isolated from the pump 164 by additional valves interposed between the DPT connections and the intake to the pump 164. The additional valves are shown at 118. 120, 122, and 124 corresponding to the lower seal section (20 in FIG. 1) and at 126, 128, 130 and 132 corresponding to the upper seal section (18 in FIG. 1). The additional valves can also be electrically operated solenoid valves which are controlled by the system operator entering appropriate commands into the surface electronics (8 in FIG. 1). The additional valves enable measurement of differential pressure between two ports while isolating those two ports from the pump 164 for certain types of formation tests. On the side of the additional valves nearest the pump 164, the hydraulic connections from each port are joined into a single line (not separately designated). The single line is connected to a pump isolation valve, shown at 158. The opposite side of the pump isolation valve 158 is connected to the intake of the pump 164. The intake of the pump 164 is also connected to a pressure transducer 162 which can be of a type known in the art generating electrical signals corresponding to the pressure applied to the pressure input of the transducer 162. As can be readily understood by those skilled in the art, the electrical signals can be conducted to the electronics section (16 in FIG. 1) for transmission to the surface electronics (8 in FIG. 1) decoding and interpretation. The pump 164 intake is further connected to an equalizer valve 160, which can also be an electrically operated solenoid type known in the art. The equalizer valve 160 is provided to enable pressure balancing between the hydrostatic pressure in the wellbore (2 in FIG. 1) and any of the ports in either the first or second seal section (18 or 10 in FIG. 1) from which fluid may have been withdrawn and the pressure at that port correspondingly reduced. Equalizing the pressure can reduce the possibility that the tool (10 in FIG. 1) might become stuck in the wellbore 2. The pump isolation valve 158 can be closed to enable operation of the pump 164 for withdrawing fluid, for example, from the wellbore 2 while differential pressure measurements can be made between radially spaced-apart ports as previously described herein as fluid from the wellbore is discharged into the formation through some of the ports, as will be further explained. The flow ports can also be selectively connected to the discharge of a second pump, shown at 164A. In the preferred embodiment of the invention, the previously described fluid pump 164 can be a two-cylinder, bi-directional, reciprocating pump of a type known in the art comprising intake and discharge check valves (not shown) to provide a common intake line (not shown) and a common discharge line (not shown) from both sides of the pump 164. The bi-directional pump known in the art can perform the functions of both the fluid pump 164 and the second pump 164A. The second pump 164A described in the preferred embodiment of the invention can therefore include the common discharge line (not shown) of the single, bi-directional, reciprocating pump. The discharge of the second pump 164A can also include connection to a second pump isolation valve 158A, a second pressure transducer 162A, and a second equalizer valve 160A. It is to be understood that other arrangements of fluid pumps providing fluid intake at the pump equalizer valve 158 and fluid discharge at the second pump equalizer valve 158A can perform substantially the same pumping functions as the single, bi-directional, reciprocating pump of the preferred embodiment. Including the bi-directional reciprocating pump should not be construed as a limitation of the present invention. Discharge from the second pump 164A can be selectively connected to any one or combination of ones of the previously described connectors 102, 104, 106, 108, 150, 152, 154, 156 by operation of discharge control valves, shown respectively at 202, 204, 206, 208, 250, 252, 254 and 256. Selective fluid discharge can be used for various types of tests to be preformed on the earth formations (12 and 14 in FIG. 1) as will be further explained. The discharge control valves can also be electrically operated solenoid valves of a type known in the art. Control signals for the discharge control valves can be generated by the surface electronics (8 in FIG. 1) in response to the system operator providing appropriate commands. The control signals can be decoded in and conducted to the valves from the electronics section (16 in FIG. 1) as will be readily understood by those skilled in the art. By operating the isolation valves, the additional isolation valves, the pump isolation valves and the discharge control valves in the appropriate sequences, the system operator can perform various tests on the earth formations (12, 14 in FIG. 1) which may be indicative of certain hydraulic properties of the earth formations (12, 14 in FIG. 1). For example, the valves can be operated so as to cause the pump 164 to withdraw fluid from the formation through all four of the ports on the first seal section (18 in FIG. 1). All of the valves connected to the flow ports on the second seal section (20 in FIG. 1), as shown at 118, 120, 122 and 124, can be closed to enable differential pressure measurement to be made between any two adjacent ports on the second seal section (20 in FIG. 1). Differential pressure developed between two adjacent ports on the second seal section could be indicative of hydraulic discontinuities in the earth formations (12, 14 in FIG. 1), as is understood by those skilled in the art. After identification of an hydraulic discontinuity at two adjacent ports as previously described, it is further possible, for example, to operate the valves to selectively direct the discharge of the second pump 164A from one of the ports associated with the discontinuity, and to measure the pressure at selected individual ones of the adjacent ports, until the hydraulic discontinuity is resolved between two ports. In another type of test of the earth formation, it is possible to operate all of the valves associated with ports of the same seal section (such as 18 or 20 in FIG. 1) to connect those ports to the pump intake 164, thereby causing the tool (10 in FIG. 1) to withdraw fluid from a zone in the earth formation (12 or 14 in FIG. 1) positioned between the seal lips (32, 34 in FIG. 2) on the bladder (26 in FIG. 2). When the valves are operated in this configuration, the DPT's are all in hydraulic communication with their respective interconnected flow ports, therefore differences in pressure between any two adjacent ones of the ports can indicate radial differences in permeability of the earth formation (12, 14 in FIG. 1). Many other types of tests of the earth formation which can resolve axial or radial differences in fluid flow properties can be readily devised by those skilled in the art using the apparatus of the present invention. It is to be further understood that the valve arrangement disclosed herein is not an exclusive representation of the possible valve arrangements which can perform the functions of the present invention. Accordingly, the invention should be limited in scope only by the claims appended hereto.

An apparatus for withdrawing fluid from an earth formation comprising an elongated housing, a first inflatable elastomeric seal adapted to expansively fill an annular space between the housing and the wall of a wellbore. The seal includes axially spaced seal lips protruding from a surface of the seal. The seal lips circumscribe the seal and define a flow channel therebetween. The flow channel includes radially spaced filler blocks which divide the channel into radial segments. Each segment further includes a flow port. The apparatus includes means for inflating the seal. The apparatus includes valves connected to each of the flow ports for connecting selected flow ports to an intake of a fluid pump and connecting selected other flow ports to a discharge port of the pump. The pump is operable in conjunction with the valves to withdraw fluid from selected flow ports and to discharge fluid into other flow ports. The apparatus includes a fluid discharge port connected to the valves, and in hydraulic communication with the wellbore so that fluid withdrawn from the flow ports can be discharged into the wellbore, and fluid withdrawn from the wellbore can be discharged through the flow ports. The apparatus includes a pressure transducer connected to the pump intake so that a pressure of the fluid withdrawn is determined. A preferred embodiment includes a second pressure transducer connected to the pump discharge and differential pressure transducers interconnected between adjacent flow ports to measure radial differences in pressure.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION As the result of the declining availability of oil, more emphasis has been directed toward the problem of more effective utilization of coal. Two methods are generally used for removing coal from the ground, either strip mining, in which the coal is merely dug out of the ground by mechanical or hydraulic means and transferred to the place of use, or underground mining using methods such as slurry mining, room and pillar, or long wall. Comminution of coal into pieces of manageable size has been accomplished by mechanical means, explosives or by chemical means. Processes for chemical comminution of coal, both above ground and below ground have been disclosed in U.S. Pat. Nos. 3,815,826 to Aldrich et al., 3,870,237 to Aldrich and 4,032,193 to Drinkard et al. According to these processes, the interlayer forces at natural interfaces present in the coal is weakened by contact with a number of reagents such as gaseous anhydrous ammonia, liquid anhydrous ammonia, aqueous ammonia, organic solvents, alcohols containing sodium hydroxide, and aqueous solutions of sodium hydroxide. Underground gasification of coal has been carried out in a number of cases to extract the energy of the coal while it is still underground. In underground coal gasification processes, a combustible gas is produced which is brought to the earth's surface and transported by pipelines. One difficulty of underground gasification is the low permeability of coal to the flow of gas therethrough. Combustion in the coal seam cannot be carried out efficiently unless an oxygen-containing gas can be passed through the seam. To cope with this problem, it has been the practice to introduce explosives into the coal seam to fracture the coal, or pneuamtic and hydraulic fracturing can sometimes be utilized. Also, permeability can be increased by injecting solvents into the coal seam as taught by U.S. Pat. No. 4,130,164 to Datta. This patent teaches the use of solvents that include various forms of ammonia and methanol that increase the permeability of the coal to the flow of fluid therethrough. It has now been discovered that by contacting the coal formation with a dry gas such as air, oxygen, oxygen-enriched air, carbon dioxide, argon, nitrogen, methane or helium, permeability of the coal formation is increased to permit fluid flow in in-situ coal gasification processes. Also, gas-drying the coal in combination with mechanical or chemical comminution enhances disintegration of the coal and enables the coal to be more easily removed mechanically or by slurry mining. SUMMARY OF THE INVENTION Broadly, this invention is a process for treating subterranean coal which comprises contacting said coal with a dry gas such as air, oxygen, oxygen-enriched air, methane, argon, carbon dioxide, nitrogen, or helium, and for a time sufficient to develop an intersecting network of cracks or fractures in the coal that weakens the coal structure and makes it easier to disintegrate either chemically or mechanically. This process can be used to increase the permeability of coal seams to the flow of gas therethrough which is important in underground coal gasification processes. Combustion cannot be carried out efficiently unless a combustion-supporting gas can be passed through the coal seam between injection and production boreholes. This process enables the permeability of the coal seam to be increased so that combustion-supporting gas and production gas can pass therethrough. The process can also be used to more easily recover coal from an underground seam in a slurry mining process. Air, argon, nitrogen, or some other drying gas can be circulated through a portion of the coal seam through a single borehole equipped with injection tubing or through a system of separate injection and production boreholes. After the fracture pattern has been developed, the coal can be fragmented and pushed or pumped to the surface by using high velocity air or water or various chemicals such as aqueous solutions of ammonia or sodium hydroxide. The process can also be used as a step in more easily disintegrating large lumps of surface coal. Chemical comminution of surface coal is greatly improved by this process wherein the coal is first treated with a drying gas such as air, argon or nitrogen. This process is particularly effective when the coal is chemically treated with aqueous solutions of sodium hydroxide. Gas-drying the coal forms a network of fractures in the coal and when the coal is treated with aqueous solutions of the sodium hydroxide, the coal disintegrates more easily than without the drying step. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simplified drawing of the cross-section of a single borehole between the earth's surface and a coal seam. FIG. 2 shows a cross-section of a formation penetrated by an injection well and a production well for carrying out the coal gasification process of the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENT This is a process for the comminution of coal by treatment with dry gas whether in a sub-surface stratum or in large lumps as mixed by standard means. The types of coal which can be treated using the process of this invention, includes lignite, sub-bituminous and bituminous. The process is particularly useful for sub-bituminous coal, especially those deposits found in Western United States, such as Wyoming. It has been found that coal will develop an intersecting network of cracks or fractures upon exposure to a dry gas such as air, oxygen, oxygen-enriched air, argon, nitrogen, helium, carbon dioxide or methane or mixtures thereof. The preferred drying gas is air or nitrogen due to their economic availability. Comminution is particularly effective when the coal is first gas-dried to form fractures and then disintegrating the coal along the fracture pattern with some mechanical or fluid force or in particular by contacting the coal with a solvent such as aqueous alkaline solutions, particularly sodium hydroxide. The alkaline treatment process particularly useful in this process is the one taught by U.S. Pat. No. 4,032,193 to Drinkard et al. and as much of that patent is pertinent here is incorporated by reference. Other chemical comminution reagents useful in combination with this process include anhydrous liquid ammonia, anhydrous gaseous ammonia, aqueous ammonia and combinations thereof, methanol, and acids as described in U.S. Pat. Nos. 1,532,826 to Lessing; 3,815,826 to Aldrich et al., 3,870,237 to Aldrich and 4,130,164 to Datta and as much as those patents as is pertinent is incorporated by reference herein. Referring to FIG. 1, when the coal lies beneath the earth's surface 10, a borehole 12 is drilled communicating between the earth's surface 10 and the coal formation 14 and penetrating overburden 16. Dry air is injected through line 18 and tubing string 20 and into contact with the coal seam 14. The dry gas penetrates the coal seam 14 and is continuously injected into the coal seam and circulated therein for a sufficient time to absorb moisture from the coal and develop a network of cracks or fractures in the coal which increases the permeability of the coal to the flow of fluid therethrough in the zone surrounding the lower end of the borehole 12. All or a portion of the moistened gas not lost in the coal seam is withdrawn through the annular opening 22 and line 24. The moistened gas withdrawn through line 22 may be de-humidified on the surface by conventional means and recycled to the coal seam. The quantity of dry gas injected into the coal seam will vary with the rank of the coal and the amount of water content contained therein. To increase the surface area of the coal exposed to the drying gas around the underground end of the wall borehole, a cavity 26 may be formed by explosive means, hydraulic pressure, or mechanical means known in the art. Once the permeability of the coal surrounding the lower end of the borehole 12 has reached a desired level, injection of the drying gas is discontinued and a basic aqueous solution is injected into contact with the coal seam 14 through line 18 and tubing string 20. The basic aqueous solution is allowed to maintain contact with the coal for a sufficient time to disintegrate or fragment the coal. The rate of the basic aqueous solution pumped down pipe 20 into contact with the coal is increased and the solution consisting of coal fragments produced by contact of the basic solution with the coal seam 14 suspended or fluidized in the form of a coal slurry is pumped out of the coal seam through annular opening 22 and pipe 24 to a storage vessel not shown. The roles of the pipe 20 and the annular opening 22 may be reversed. The basic aqueous solution useful in the process include, but is not limited to, sodium hydroxide, ammonia, potassium hydroxide, sodium carbonate, and potassium carbonate and combinations thereof. The preferred solution is sodium hydroxide. Concentrations in water solution can range from 0.01 molar to 5 molar. The process is not limited to the arrangement of FIG. 1 which utilizes a solvent for disintegrating the coal once it has been fractured and weakened by treatment with a drying gas. Therefore, other conventional comminution means may be used in combination with the drying treatment in accordance with the process shown in FIG. 1 such as mechanical disintegration using an agitating tool or the use of slurry mining hydraulic apparatus in which a pressurized fluid such as water is directed at the coal seam to disaggregate the coal and form a slurry which is then pumped out of the coal seam to the surface. In the technique of mechanical comminution, the disintegrated particles of coal may be lifted pneumatically from the coal seam to the surface. Another embodiment of the process is to increase the permeability of the coal seam between boreholes used in in-situ underground coal gasification. FIG. 2 shows an injection well 26 and a production well 28 penetrating from the earth's surface 30 through overburden 32 into a coal seam 34. In the underground gasification of coal, a combustion-supporting gas such as air or oxygen is introduced through the injection well 26, the coal is ignited and the combustion products are removed through the production well 28. The gaseous permeability of the usual coal seam is too low to permit transfer of gas from the injection well to the production well. Accordingly, it becomes necessary to increase the permeability of the coal seam by fracturing the formation using conventional means such as explosives, solvents, back burning or directionally-drilled holes. The process of the present invention is utilized for producing the necessary permeability rather than explosives, solvents or other methods. Thus, dry air is introduced into the coal seam 34 through injection well 26 and forced through the coal seam 34 to the production well 28. The dry air penetrates the coal and absorbs moisture which weakens the coal structure and forms fractures in the coal thereby increasing substantially its permeability. Introduction of the dry air is continued for a sufficient period of time so that the permeability of the coal seam 34 is increased substantially to the flow of fluid therethrough over the entire region between wells 26 and 28. The dry air enters the coal seam 34 through perforations 36 and 38 in the lower end of the injection well 26 and is directed toward production well 28. Production well 28 has perforations 40 and 42 to provide communication between the coal seam 34 and said production well 28 for withdrawal of the moistened air. After sufficient enhancement of the permeability of the coal seam between the two wells, introduction of the dry air is discontinued and in-situ combustion is then started in the manner described. The moistened air from the production well may be de-humidified and recycled to the injection well. A higher injection pressure may be required initially to establish communication between injection and production wells. A pattern involving a multiplicity of injection and production wells, in equal or unequal numbers of each, may be used. For example, a central injection well may be surrounded by a plurality of production wells in a ring pattern, such as a 5-spot well pattern. The dry gas may be heated, however, its temperature is not critical to the process and is preferably in the range of 20°-150° C. Of course, the higher the temperature, the faster the rate of drying. This invention will be further explained in detail with reference to the following embodiments which are given by way of illustration only and not by way of limitation. EMBODIMENT I Two samples of sub-bituminous coal from the Ucross seam at the Tipperary Coal Prospect, near Buffalo, Wyo. were treated. Both samples were 1/4--circle sectors (pie-shaped wedges) of approximately 1.5-inch first radius, 1.5-inch second radius, 2-inch chord and 1-inch thickness. One sample was dried in an oven having an argon temperature at 40° C. for 24 hours and the other sample was not dried. Visual inspection of the dried sample showed development of a network of fractures or cracks which were interconnected and extended approximately parallel and perpendicular to the bedding plane with a maximum spacing of about 0.4 inch and a maximum fracture opening of about 0.04 inch width. The dimensions of the dried sample were: 1.45-inch radius×1.45-inch radius×2.05-inch chord×1.05-inch thickness before drying, and 1.40-inch radius×1.40-inch radius×1.90-inch chord×1.00-inch thickness after drying. The weight before drying was 37.69 grams and after drying, 28.68 grams with a 9.01 gram weight loss or a 23.9% loss consisting of moisture. The dried and undried samples were then immersed in a 1.0 N solution of sodium hydroxide. After two hours' immersion, the undried sample was intact whereas the dried sample crumbled into small pieces. After three days' immersion, the undried sample separated into 1/8-1/4-inch thick layers along the bedding plane with about 50% of the layers intact (1.76 square inch area) and the rest broken into 1.0 to 0.25 square inch pieces. After three days' immersion, the dried sample was visually inspected and the largest piece was approximately 0.25 square inch×0.25 inch thick with most pieces smaller than a cube 0.2 inch on a side. EMBODIMENT II Two sub-bituminous coal samples from the Ucross seam at the Tipperary Coal Prospect near Buffalo, Wyo. were treated. Both samples were approximately 1-inch thick, 1/8-circle sectors (pie-shaped wedges) cut from a 3-inch diameter core. One sample, with measurements of 1.20-inch first radius×1.05-inch second radius×1.00-inch chord×0.90-inch thickness, was dried in an air-circulating oven at 32° C. After one hour of drying, a fracture network was evident with a weight loss of 5.3%. After three hours of drying, the fracture network was fully developed consisting of an approximately rectangular network of fractures with spacing randomly varying from 0.2 to 0.05 inch. The weight loss after three hours' drying was 7.1%. After 201/2 hours' drying, the weight loss was 20.4%, the fracture gaps were about 0.04 to 0.02 inch and the size of the sample measured 1.15-inch radius×1.00-inch radius×0.92-inch chord×0.88-inch thickness. The undried and dried samples were then immersed in a 1 N solution of sodium hydroxide. After two hours' immersion, there was no visual effect on the undried samples which remained intact whereas the dried sample crumbled into mostly small fragments with some large pieces approximately 1/2 inch square×1/8 inch thick. After three days' immersion, the undried sample was visually inspected and consisted of one 0.4 inch thick full-layered piece, one 0.2 inch thick full-layered piece, and pieces of 1/8-1/4-inch thick layers broken into 1/4 square inch pieces or smaller. After three days' immersion, the dried sample was visually inspected and consisted of small fragments cubical or rectangular-faced in shape and approximately 0.2 inch on a side or less, but mostly 0.1 inch on a side.

This invention is a comminution process for treating coal with a drying gas to form fractures which weaken the structure of the coal and make it easier to disintegrate mechanically, chemically or by fluid force. Another aspect of this invention is a process for treating an underground formation of coal with a dry gas for a time sufficient to form cracks and fractures in a portion of the formation in order to increase the permeability of the coal formation to the flow of fluids therethrough. Processes for in-situ combustion of the coal formation are therefore more efficient since the coal formation is more permeable to the flow of gas therethrough.

You are an expert at summarizing long articles. Proceed to summarize the following text: This is a continuation of application Ser. No. 560,124 filed Dec. 12, 1983, now U.S. Pat. No. 4,571,126 issued on Feb. 18, 1986. BACKGROUND OF THE INVENTION This invention relates to an expansion body for constructions located in the earth including a folded elongated casing and a first and a second closure arranged at the upper and lower end respectively of the casing, said casing and closures defining an internal closed space connectable to a source of pressurized fluid for the expansion of the body by pressing out the folds of the casing. Expansion bodies of the kind mentioned above have been proposed for in situ piles and especially as an expanded foot of these. When such piles are used, the casing is first inserted into the ground and then filled with pressurized water or concrete for pressing out the folds thereof thus giving the pile its final shape. A problem related to expansion bodies of that kind has been the arrangement of the end closures. The reason for this is that said closures must be designed for sealing the end parts of the casing as well as for enabling the foldings to unfold gradually from the ends without causing cracking tensions in the casing. According to one known proposal for such an expansion body, the closures are shaped like cone-formed endings of the casing with successively decreasing depths of the foldings. Closures like that are, however, in practice impossible to manufacture for a reasonable cost. They are also unsuitable for closely folded casings or when there is a need for larger inlets or tubes leading through the casing. An object of the present invention is to provide an expansion body with end closures which eliminate the drawbacks mentioned above. Another object is to provide an end closure which is simple and cheep to manufacture and mount on the ends of the casing. These objects and others are achieved by providing an expansion body according to the accompanying claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal cross section of an expansion body according to the invention. The section is taken along the line 1--1 in FIG. 2. FIG. 2 is a cross section according to the line 2--2 in FIG. 1. FIGS. 3 and 4 are a cross section of two sheets and a die beam, showing schematically the manufacture of the expansion body according to FIG. 1. FIG. 5 is a side view of an expanded body according to FIG. 1. FIG. 6 is a cross section according to the line 6--6 in FIG. 5. FIG. 7 is a longitudinal cross section of the lower end part of the casing with an alternative attachment between the closure and the casing. FIG. 8 is the same section as FIG. 7 but showing still another attachment. FIG. 9 shows the closure according to FIG. 8 partly finished. DETAILED DESCRIPTION The expansion body according to FIG. 1 includes a folded casing 11 and end closures 12, 13 arranged at the upper and lower end 14, 15 respectively of the casing 11. The casing 11 which is preferably made of sheet metal is folded in zig-zag shape in a way that appears from FIGS. 4 and 5 and will be described more in detail later on. In FIG. 1 the folds are only shown schematically. Each closure 12, 13 comprises a socket or end cap 16, 17 with a sleeve portion 18, 19 and a bottom portion 20, 21. The sleeves 18, 19 have preferably a square cross section in order to closely fit within a predrilled hole in the ground to provide for a high degree of expansion. The bottom portions 20, 21 in the form of square plates of steel are welded to the sleeves 18, 19 respectively for forming a sealed ending. Tubular spacing means 22 and 23 respectively are welded to each bottom plate 20, 21 to form part of the sockets 16, 17. They have a rectangular cross section and provide annular spaces 24, 25 between themselves and the sleeves 18, 19. The spaces 24, 25 are arranged for receiving the end parts 14 and 15 respectively of the casing 11 and each space 24, 25 comprises two wide parts 26 in which the casing is folded and two narrow parts 27 in which the casing is flat (FIG. 2). The upper closure 12 includes a fitting 28 welded to the bottom plate 20 of the socket 16. The fitting 28 has an internal thread 29 for connection with a conduit in the form of a pipe, not shown, from an external source of pressurized fluid. The fluid, for example concrete, water or air is conveyed into the internal space of the casing through a passage 30 in the bottom plate. To prevent the fluid from leaking between the folds in the socket, a sealing agent 31 is arranged to fill up possible openings between the folds and between the end part 14, 15 of the casing and the socket 16, 17. The sealing agent 31 is preferably some viscous substance as for example asphalt but other substances can also be used for example different plastics. Four connecting rods or substantially flat plates 32 are welded to the sockets 16, 17 for retaining them on the casing ends when the pressurized fluid starts to unfold the casing. It might be sufficient with two rods 32 but it is preferred to have four so that the casing can be protected by them during handling, transportation and insertion in the ground especially when the expansion body is rammed into the ground instead of inserted into a pre-bored hole. The rods are adapted to follow the contour of the casing during the expansion of the body, see FIG. 5, and will thus bring the sockets 16, 17 closer to each other as the body shortens due to the expansion. Thus, the sockets 16, 17 need not be directly affixed to the respective ends of the casings. In the embodiment described above, the expansion body is arranged to be the expanded end of a pile or anchor. The non-illustrated tube screwed to the fitting 28 forms the stem of the pile or anchor. Reinforcing bars can be inserted through the stem and into the expansion body before concrete is forced into the tube to expand the expansion body and form an integral concrete anchor or pile that consists of a stem and a foot. Several expansion bodies can be arranged on the same stem at desired axial intervals. The inner sleeves 22, 23 can then be dispensed with and the stem forming tube can have the same dimension as the sleeves 22, 23. The bottom plates 20 can be welded directly to the tube. The stem forming tube should then have several big holes into the expansion body for permitting concrete to pass into the expansion body and for providing sufficient concrete bridges between the concrete in the stem and the concrete in the expansion body. It is also possible to arrange the expansion bodies on pre-formed concrete piles. The concrete for expanding the body or bodies can then be injected through a channel in the concrete pile or through conduits outside the pile. In all the embodiments described, the pile or anchor with the expansion body or bodies thereon can be inserted into a pre-drilled hole in the ground or they can be forced into the ground. When they are forced into the ground, the bottom end should be provided with a shoe that can be formed as an arrow point. A preferred way of manufacturing the expansion body is to start with rolling an iron sheet to a zig-zag shaped sheet which is cut into smaller sheets of a suitable size. Two such sheets 40, 41, see FIG. 3, are laid over each other, face to face, so that the folds 42 of the first sheet 40 fall into the folds 43 of the second sheet 41. Along their middle portions, the sheets 40, 41 form an opening 44, 45 of about the same size as the spacing sleeves 22, 23. A die beam in the form of a box girder 46 with the same rectangular cross section as the spacing sleeves 22, 23 is arranged to be located in the opening 44, 45 when the two sheets are inserted in each other, see FIG. 4. FIG. 2 is somewhat misleading. The spacing sleeve 22 should have the same size in FIG. 2 as in FIG. 1. The two longitudinal side edges 47, 48 are welded and the double sheet is pressed in a press, not shown, as indicated by the arrows F. The pressing is finished when the folds 42, 43 are in close abutment with each other, as in FIG. 2. Then the beam 46 is withdrawn from the internal space 49 established by the opening 44, 45 and the sleeves 18, 19 are put onto the ends of the casing 11. Then, the spacing sleeves 22, 23, to which bottom plates 20, 21 have been welded, are inserted into the internal space 49 and the bottom plates 20, 21 are welded to the sleeves 18, 19. The connecting rods 32 are then attached to the sleeves 18, 19 by welding and the ends of the expansion body are dipped into hot fluent asphalt which fills up and seals possible passages between each end part 14, 15 of the casing 11 and the respective socket 16, 17 as well as between the folds in the socket. The asphalt or other sealing agents penetrates also into the folds between the two sheets 40 and 41. The end closures 12, 13 so obtained are adapted for keeping the parts of the casing 11 which are located in the sockets 16, 17 in a folded position when the casing outside the sockets is unfolded and expanded. This is achieved since the folds are retained tightly adjacent to each other within the wide parts 26 of the spaces 24, 25 in the sockets. But it is also necessary to provide for some sliding motion in the sockets, otherwise extreme tensions will appear adjacent the sockets which tensions might cause the casing to crack. For that reason the space part 26 is wide enough to allow the folds of the two opposed sheets 40, 41 to move in opposite directions sliding against one another as can be seen in FIG. 6 The folds 42 and 43 of the first and second sheet 40 and 41 respectively turn about opposite edges 50 and 51 of the sleeves 18, 19 so that the edges bend somewhat outwards. The turning and sliding movement is longest for the folds which are located closest to the spacing tube 22 and it decreases successively towards the outer folds. The casing 11 may tear up close to the tubes 22 and 23 which results in slits 52, 53 as indicated in FIG. 6 but otherwise the casing 11 does not crack. The sliding movement is facilitated by the part of the sealing agent 31 which has penetrated inbetween the two sheets 40, 41. The pressure needed for axpanding the casing 11 varies with the formation in which it is located. The pressure can typically be between a few bars and 50 bars depending on the depth and the formation. In application for which a comparatively low pressure is sufficient, the end closures 12, 13 can alternatively be attached directly to the end parts of the casing 11 as shown in FIGS. 7-9. In the embodiment according to FIG. 7 this is done by drilling a hole through the end caps 16, 17 and the casing 11 and inserting a bolt 54 in the hole. In another embodiment according to FIGS. 8 and 9 the end caps or sockets 16, 17 are welded to the ends of the casing by welding seam 55 between the sleeve portion of the socket and the part of the casing that is not folded. The welding seam 55 is applied to the inside of the sleeve as appears from FIG. 9 and the end cap is finished by welding the bottom plate to the wall portion by a welding seam 56, as can be see in FIG. 8. It is to be understood that the invention is not limited to the disclosed examples but can be varied in many ways within the scope of the claims. For example the casing can be folded in other ways.

An expansion body for constructions like piles or anchorages located in the earth is adapted for insertion into the ground in a compact shape and expanded therein to an expanded shape. The expansion is achieved by unfolding a folded metallic casing (11) by filling it up with pressurized fluid. Each end of the elongated body is sealed by a closure comprising a socket (16, 17) with a sleeve (18, 19) encircling the near end part of the casing and a bottom plate (20, 21) with spacing means (22, 23) projecting into the inside of the casing. The sleeve (18, 19) and spacing means (22, 23) define an annular space (26, 27) in which the end parts (14, 15) are kept in a folded position when the body is expanded.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Technical Field The invention relates generally to the field of log structures. More specifically, the invention is directed to an improved corner assembly of a log structure and a method for constructing same. 2. Description of Prior Art Log structures are well-known in the art. These include log cabins, log outbuildings, and other structures where the exterior walls are primarily constructed of logs. Walls for log structures erected by known construction methods are typically constructed at the building site, one log placed upon another one at a time. This method is required in order to connect the ends of logs forming two adjacent walls, whereby such logs must overlap each others' ends to form a structurally sound corner between the two walls. This method is time consuming and weather dependent, and involves a great deal of manual labor. It does not lend itself to the prefabrication of walls for log structures. However, prefabrication of walls in general allows for much greater construction efficiencies, because the walls may be erected within an enclosed environment, without regard to weather conditions at the building site. There are also efficiencies of scale achieved with prefabrication. Final assembly of a structure at the building site is much faster if the walls are prefabricated, and final assembly is more readily performed with the assistance of machinery, such as cranes, thereby reducing labor expense and the total time required. Construction methods involving prefabricating wall panels at a remote location and then installing the panels at the work site are well known in the art. See, e.g., Weiss, U.S. Pat. No. 6,951,079 (Oct. 4, 2005), “System and Method of Panelized Construction”. However, none of these methods have been adapted for the walls comprising log structures such that the individual walls can be easily erected and mated together, then made secure. The prior art discloses various methods for mating adjacent walls of log structures. Traditional methods include using logs with notches cut into their surfaces near the log ends, such that the end of a log of one wall will snugly fit into the notch of an adjacent log of the second wall. See Garber, U.S. Pat. No. 4,901,489 (Feb. 20, 1990), “Log for Constructing Log Structures and Associated Log Fabricating Process”; Paxton, et al., U.S. Pat. No. 6,059,630 (May 9, 2000), “Log Based Assembly Kit”; Chambers, U.S. Pat. No. 6,564,526 (May 20, 2003), “Accelerated Log Building Method”; Morgenstern, U.S. Pat. No. 6,851,233 (Feb. 8, 2005), “Cast Log Structure”. These construction methods, however, require each log to be placed one at a time to fit the notch of the underlying log. This does not lend itself to rapid construction. Still other methods are known in the art wherein the ends of the logs themselves are notched, tongue-in-groove style. See Wrightman, U.S. Pat. No. 4,392,520 (Jul. 12, 1983), “Log Building Construction”; Magnuson, U.S. Pat. No. 4,510,724 (Apr. 16, 1985), “Building Structure”; Moore, U.S. Pat. No. 5,799,452 (Sep. 1, 1998), “Log Construction”; Davis, et al., U.S. Pat. No. 6,931,803 (Aug. 23, 2005), “Modular Building System”. In each of these construction methods, however, the corners are mated together snugly, so individual logs must still be placed one at a time or the adjacent walls cannot be mated. Construction methods using alternating protruding logs are also known in the art. See Faw, U.S. Pat. No. 4,463,532 (Aug. 7, 1984), “Prefabricated Wall Unit for Log Building Construction, Method of Producing Same and Method of Constructing Log Building Therewith”; Calkins, U.S. Pat. No. 6,418,680 (Jul. 16, 2002), “Log Panel System with Panels Comprising a Plurality of Stacked Logs and an End Board Fixedly Attached to the Ends of Each Panel”. In this construction method, the alternating logs and the spaces between them serve the function of the notched out tongue-in-groove design described above. But as with the previously described methods, the mating log ends are very snug when the wall is completed, again requiring log by log construction. Thus none of the disclosed prior art anticipates the present invention. The present invention seeks to alleviate the aforesaid problems, by providing a method of construction whereby adjacent walls having alternating protruding log ends can be easily mated at the corners during erection of the walls, thus lending itself to the use of prefabricated walls for log structures. As such, full walls may be built in a weather-independent environment, such as an enclosed assembly plant, and then moved to the building site, ready to be erected. This creates a savings in time and money, because of the efficiencies of prefabrication at a single location and the independence from weather conditions. Erection time of a log structure at the building site when prefabricated log walls are used is a matter of hours, rather than days or weeks under old log-on-log methods. Multiple homes can be constructed at once in the assembly plant, further increasing efficiencies. It is therefore an objective of the present invention to provide a useful, improved log structure that can be prefabricated in a remote location away from the building site. It is further objective of the present invention to provide a useful, improved log structure that can be prefabricated in a weather-independent environment. It is further objective of the present invention to provide a useful, improved log structure that consists of prefabricated walls which can be transported fully assembled to the building site. It is further objective of the present invention to provide a useful, improved log structure that can be quickly erected using mechanical means to lift and position fully assembled walls, such as cranes. It is further objective of the invention to provide a method for erecting useful, improved log structures utilizing prefabricated walls. Other objectives of the present invention will be readily apparent from the description that follows. SUMMARY OF THE INVENTION The present invention is an improved log structure and method for constructing same. The log structure is comprised of at least two adjacent walls mated together to form a corner. Each wall is constructed of logs laid horizontally upon each other. The logs alternate between protruding and nonprotruding logs, where the protruding log ends extend laterally beyond the ends of the nonprotruding logs. The ends of the protruding logs are aligned with each other to a substantially uniform degree, and the ends of the nonprotruding logs are aligned with each other to a substantially uniform degree. The protruding log ends extend beyond the ends of the nonprotruding logs at least a distance greater than the diameter of the protruding logs. The protruding logs of one wall are aligned with the nonprotruding logs of the adjacent wall. The corner assembly is formed by the interleaving of alternating protruding log ends extending beyond the side edge of each adjacent wall. Each protruding log end fits into the space created between two protruding log ends of the adjacent wall. Because the logs comprising the walls are substantially identical in dimension, the space between any two protruding log ends is substantially identical to the diameter of the protruding log end to be fit therebetween. As such, two fully assembled adjacent walls cannot be mated together because of the resulting high degree of friction between the interleaved protruding log ends. The only way to construct the log structure having this corner assembly design, therefore, is to alternate the laying of logs from the two adjacent walls. The resulting corner assembly will have a tight and secure fit, but the assembly is log on log at the building site. The present invention solves the above-described problem by incorporating a removable element, known as a plug, into the protruding end of each of the logs in at least one of the walls. The plug fits into a notch formed into the protruding end of each of the logs. The notches may be cut from the top portions of the protruding log ends or the bottom portions of the protruding log ends, as desired. When the plug is removed from the log ends, the spaces between each pair of protruding log ends becomes greater than the diameter of the adjacent protruding log end to be fit in between. This increased space eliminates any frictional forces between the two adjacent walls during assembly. As a result, two fully and independently assembled walls may be brought together easily and the protruding log ends interleaved to form a corner assembly. Once the adjacent walls are placed in their desired positions and secured to each other, the plugs are replaced, achieving the same snug fit as would have resulted if the walls were erected using a log on log construction method. While there is some friction involved in reinserting the plugs, this can be dealt with much easier than attempting to mate an entire wall to another. Moreover, given the slight degree of inherent play in the protruding ends of the logs, there will be only a single plug which will experience the full degree of frictional forces when being reinserted, namely the final plug to be inserted. The method of the present invention comprises the steps of preparing the logs for each wall at a remote location, such as at an assembly building; assembling each wall in its entirety without the plugs, independently from the adjacent wall; then transporting the two fully assembled walls to the building site and positioning them as desired. Machinery, such as cranes, can be used to assist with the positioning of the walls. Once the walls are positioned correctly and secured to each other, the plugs are reinserted, completing the corner assembly. The plugs can optionally be secured within the log ends by mechanical fasteners or adhesives. While the plugs can be formed of the portions of the protruding log ends removed to make the notches, plugs made from other materials may also be used, provided they fit snugly within the notches once the two walls are properly mated. Moreover, if the plugs are all cut from the log ends to a substantially uniform shape and dimension, a plug cut from one log end may be reinserted into the notch of a different log end. This adds to the ease of construction because individual plugs need not be associated with any particular notch. When four walls are to be used, for example, as a log cabin, only two opposing walls need have their protruding ends notched for removable plugs. The two adjacent walls can be constructed with unnotched log ends. However, the protruding ends of all four walls may be notched, if desired. This would create an even greater space between any pair of protruding log ends, though twice as many plugs would have to be replaced. Where more than four walls are used, any number of those walls may have their protruding log ends notched, as long as at least one side of a wall of every pair of walls is notched. Similarly, a fully assembled wall may have the protruding log ends notched only on one side; if this arrangement is used, then the wall adjacent to the unnotched side of the wall must in turn have its protruding log ends notched. The use of plugs in the ends of the protruding logs is novel and not anticipated by the prior art. Moreover, the ability to prefabricate entire walls for log structures and then to erect them an entire wall at a time at the building site is not anticipated by the prior art. Other features and advantages of the invention are described below DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view of the first wall and the second wall of the present invention, with a plurality of dotted lines indicating how the first and second walls are to be placed together, and further disclosing the notches of the first protruding log members and one plug, with a single dotted line indicating the how the plug is to be positioned within a notch. FIG. 2 is a perspective view of the first wall and the second wall depicted in FIG. 1 in their desired final orientation to each other, and further disclosing the plugs completely or partially inserted within the notches of the first protruding log members, with one plug yet to be inserted. FIG. 3A is a side view of the first wall depicting the alternating arrangement of first protruding log members and first nonprotruding log members, as well as the location of the notches within the ends of the first protruding log members and how the plugs would be inserted therein. FIG. 3B is an exploded view of the first wall and an end view of the second wall, with a plurality of dotted lines indicating how the first and second walls are to be placed together, where the notches are shown with the plugs removed to disclose the gaps between pairs of the first protruding log members sufficiently large to accommodate the second protruding log members of the second wall. FIG. 4A is a side view of the first wall and an end view of the second wall depicted in FIG. 3B in their desired final orientation to each other, and further disclosing how the plugs may be inserted within the notches to complete the assembly. FIG. 4B is a side view of the second wall and an end view of the first wall, being a ninety degree rotation of the first and second walls depicted in FIG. 4A . FIG. 5A is a side view of the first wall and an end view of the second wall as depicted in FIG. 4A , showing an alternate embodiment of the present invention whereby the notches formed into the bottom of the first protruding log members of the first wall. FIG. 5B is a side view of the second wall and an end view of the first wall, being a ninety degree rotation of the first and second walls depicted in FIG. 5A . DETAILED DESCRIPTION OF THE INVENTION The log structure of the present invention comprises a first wall 100 and a second wall 200 . See FIG. 1 . Each wall 100 , 200 is defined to have a side edge, said side edge running from the top of the wall to the bottom of the wall. The side edge of the first wall 100 is suitably adapted to be joined with the side edge of the second wall 200 to form a corner assembly. Each of the first wall 100 and the second wall 200 is constructed of at least three log members 110 , said log members 110 oriented substantially horizontally and stacked substantially vertically one upon another, and affixed in place. The log members 110 may be rough hewn logs, debarked logs, shaped logs, such as “D”-shaped logs known in the art, or other configurations of logs used for construction. In the preferred embodiment each wall 100 , 200 comprises several more than three log members 110 each, though the walls 100 , 200 do not need to have the same number of log members 110 . Each log member 110 is defined to have an end 112 and a top portion 114 . See FIG. 1 . The top portion 114 of a log member 110 is defined as the uppermost portion of a log member 110 when the log member 110 is oriented substantially horizontally and affixed in place. For the first wall 100 , the log members 110 are identified as base log members 120 , top log members 130 , and first log members 140 . See FIG. 3A . The first wall 100 has one base log member 120 , one top log member 130 , and one or more first log members 140 . The base log member 120 is the log member 110 that comprises the lowermost portion of the first wall 100 and is placed on a surface, such as the ground, a foundation, the top of another wall, or the like. One first log member 140 is placed onto the top surface of the base log member 120 and affixed to the base log member 120 . The remaining first log members 140 , if any, are placed onto the top surfaces of the first log members 140 already affixed to the first wall 100 , and affixed thereto. The top log member 130 is placed onto the top surface of the last log member 110 to be placed and is affixed thereto, comprising the topmost portion of the first wall 100 . The ends 112 of all log members 110 comprising the first wall 100 form the side edge of the first wall 100 . The log members 110 of the first wall 100 (exclusive of the top log member 130 ) are further identified as first protruding log members 150 and first nonprotruding log members 152 . See FIG. 3A . The end 112 of each first protruding log member 150 extends laterally beyond the end 112 of each first nonprotruding log member 152 . Moreover, the end 112 of each first protruding log member 150 is substantially vertically aligned with the end 112 of each other first protruding log member 150 . Similarly, the end 112 of each first nonprotruding log member 152 is substantially vertically aligned with the end 112 of each other first nonprotruding log member 152 . The base log member 120 is a first protruding log member 150 . If there is an even number of first log members 140 , half the number of the first log members 140 are first nonprotruding log members 152 and half are first protruding log members 150 . If there is an odd number of first log members 140 , the first log members 140 will be comprised of one more first nonprotruding log members 152 than first protruding log members 150 . The configuration of the end 112 of the top log member 130 depends on the configuration of the end 112 of the first log member 140 upon which it is placed. If the first log member 140 upon which the top log member 130 is placed is a first protruding log member 150 , the end 112 of the top log member 130 is substantially vertically aligned with the ends 112 of the first nonprotruding log members 152 . If the first log member 140 upon which the top log member 130 is placed is a first nonprotruding log member 152 , the end 112 of the top log member 130 extends laterally beyond the ends 112 of the first nonprotruding log members 152 and is substantially vertically aligned with the ends 112 of the first protruding log members 150 . The first protruding log members 150 and the first nonprotruding log members 152 are arranged in an alternating manner. See FIG. 3A . Thus, from the base of the first wall 100 , the side edge of the first wall 100 is comprised of alternating protruding and nonprotruding ends 112 of log members 110 . The configuration of the top log member 130 adheres to this pattern. The log members 110 comprising the second wall 200 are similarly identified and configured as are those of the first wall 100 . See FIG. 4B . For the second wall 200 , the log members 110 are identified as second base log members 220 and second log members 240 . The second wall 200 has one second base log member 220 and two or more second log members 240 . The second base log member 220 is the log member 110 that comprises the lowermost portion of the second wall 200 and is placed on a surface in the same manner as the base log member 120 of the first wall 100 . One second log member 240 is placed onto the top surface of the second base log member 220 and affixed to the second base log member 220 . The remaining second log members 240 are placed onto the top surfaces of the second log members 240 already affixed to the second wall 200 , and affixed thereto. The ends 112 of all log members 110 comprising the second wall 200 form the side edge of the second wall 200 . The log members 110 of the second wall 200 are further identified as second protruding log members 250 and second nonprotruding log members 252 , analogous to the first protruding log members 150 and first nonprotruding log members 152 of the first wall 100 . See FIG. 4B . The second base log member 220 is a second nonprotruding log member 252 . If there are an even number of second log members 240 , half the number of the second log members 240 are second protruding log members 250 and half are second nonprotruding log members 252 . If there is an odd number of second log members 240 , the second log members 240 will be comprised of one more second protruding log members 250 than second nonprotruding log members 252 . The second protruding log members 250 and the second nonprotruding log members 252 are arranged in an alternating manner. See FIG. 4B . Thus, from the base of the second wall 200 , the side edge of the second wall 200 is comprised of nonprotruding and protruding ends 112 of log members 110 . The result is that the side edge of the first wall 100 has log members 110 whose protruding ends 112 are aligned with the nonprotruding ends 112 of the corresponding log members 110 of the second wall 200 when the side edge of the first wall 100 is adjacent to the side edge of the second wall 200 . See FIG. 2 . For each first protruding log member 150 of the first wall 100 , the end 112 of the first protruding log member 150 comprises a notch 160 and a plug 170 . See FIGS. 1 , 3 A, 4 A, 4 B. The notch 160 is formed by the removal of a portion of the top portion 114 of the first protruding log member 150 at the end 112 of the first protruding log member 150 . See FIGS. 4A , 4 B. The notch 160 has a substantially vertical face 162 and a substantially horizontal base 164 . See FIG. 1 . The base 164 of the notch 160 extends inward from the end 112 of the first protruding log member 150 , and the face 162 of the notch 160 is adjacent to the portion of the base 164 furthest from the end 112 of the first protruding log member 150 . The plug 170 of each first protruding log member 150 is a solid block corresponding in shape and dimension to the notch 160 of that first protruding log member 150 . The plug 170 must be removably positionable within the notch 160 . The notch 160 and plug 170 combination serves to facilitate assembly of the log structure, as will be described in more detail below. In brief, with the plugs 170 removed from the corresponding ends 112 of the first protruding log members 150 , the spaces between each pair of first protruding log members 150 will be greater than the diameter of the log members 110 , thus allowing easy interleaving of the ends 112 of the protruding log members 110 of the first and second walls 100 , 200 . See FIG. 3B . When completed, the log structure of the present invention has its first wall 100 adjacent to and connected to its second wall 200 , with the first protruding log members 150 of the first wall 100 interleaved with the second protruding wall members of the second wall 200 . See FIG. 2 . As such, the side of the first wall 100 and the side of the second wall 200 form a corner of the log structure. For each first protruding log member 150 of the first wall 100 , its corresponding plug 170 is positioned within its notch 160 . The placing of the plug 170 within the notch 160 fills in the gap between the interleaved ends 112 of the protruding log members 110 of the first and second walls 100 , 200 , resulting in a snug fit. See FIGS. 2 , 4 A, 4 B. In one embodiment of the present invention, for each first protruding log member 150 of the first wall 100 the corresponding plug 170 is of substantially the same shape and dimension as each other plug 170 of each other first protruding log member 150 . In this configuration, the plug 170 of each first protruding log member 150 is suitably adapted to be positioned with the notch 160 of each other first protruding log member 150 . This arrangement facilitates assembly of the log structure, as specific plugs 170 need not be matched with specific log members 110 . Where the plugs 170 are cut directly from the ends 112 of the log members 110 , this uniformity of shape and dimension represents a significant savings in time with regard to preparation of the log members 110 and assembly of the log structure. In the preferred embodiment, for each first protruding log member 150 , the width of the notch 160 and corresponding plug 170 is substantially equivalent to the horizontal cross-sectional diameter of that first protruding log member 150 , and the height of the notch 160 and corresponding plug 170 is less than one half the vertical cross-sectional diameter of that first protruding log member 150 . This ensures that more than half of the material comprising the end 112 of the first protruding log member 150 remains after creation of the notch 160 , providing strength to the end 112 of the first protruding log member 150 . Finally, the depth of the notch 160 and the corresponding plug 170 is substantially equivalent to the length of the end 112 of the first protruding log member 150 that extends laterally beyond the ends 112 of the adjacent first nonprotruding log members 152 . This allows the notch 160 to accommodate the interleaved end 112 of a second protruding log member 250 snugly against the end 112 of the adjacent first nonprotruding log member 152 . Each plug 170 may be frictionally secured within a notch 160 . That is, the tight tolerances of the plug 170 within the notch 160 between the interleaved protruding ends of the first and second walls 100 , 200 may be sufficient to retain the plug 170 securely in place. Alternately, the plug 170 may be fixedly attached within the notch 160 by one or more mechanical fasteners, such as nails or screws. In the preferred embodiment, the plugs 170 are fixedly attached within the notches 160 by an adhesive, such as wood glue or a product known as Liquid Nails®. An alternative embodiment of the log structure of the present invention contemplates a reverse alternation of the log members 110 , such that the base log member 120 of the first wall 100 is a first nonprotruding log member 152 , and the second base log member 220 of the second wall 200 is a second protruding log member 250 . See FIG. 5A . The remaining log members 110 of each wall are arranged as protruding or nonprotruding log members 110 as before. The top log member 130 of the first wall 100 is a first protruding log member 150 if the first log member 140 upon which it is placed is a first nonprotruding log member 152 , and the top log member 130 of the first wall 100 is a first nonprotruding log member 152 if the first log member 140 upon which it is placed is a first protruding log member 150 . A significant aspect of this embodiment is that for each first protruding log member 150 of the first wall 100 , the notch 160 is formed from the bottom portion 116 of the log member 110 at the end 112 of the first protruding log member 150 . See FIGS. 5A , 5 B. The bottom portion 116 of the log member 110 is defined as the lowermost portion of the log member 110 when the log member 110 is oriented substantially horizontally and affixed in place. Other than the location of the notch 160 , all other aspects of the configuration of the notch 160 and corresponding plug 170 are the same as in the prior embodiments. In this embodiment, the second base log member 220 of the second wall 200 is a second protruding log member 250 , with the remaining log members 110 alternating as before. The present invention also contemplates a method for constructing the log structure described above. The steps are as follows: The log members 110 of the first wall 100 are prepared, by performing the following three sub-steps in any order: the base log member 120 and half the number of first log members 140 are cut to desired lengths, such that the base log member 120 and the first log members 140 have a suitable length to be utilized as first protruding log members 150 ; the remaining first log members 140 are cut to desired lengths, such that the remaining first log members 140 have a suitable length to be utilized as first nonprotruding log members 152 ; and the top log member 130 is cut to a desired length, such that said top log member 130 has a suitable length to be utilized as either a first protruding log member 150 or as a first nonprotruding log member 152 , as determined by and opposite to the first log member 140 upon which it will be placed. The next step is to prepare all first protruding log members 150 by cutting a plug 170 from the top portion 114 of the end 112 of each first protruding log member 150 to form a notch 160 and then removing the plug 170 from the notch 160 . This step may be performed by automated sawmill machinery which can be configured to cut uniform plugs 170 from the ends 112 of all first protruding log members 150 . The next step is to assemble the first wall 100 . This is accomplished by placing the base log member 120 in a substantially horizontal position upon a surface, such as the floor of an assembly building; placing one first nonprotruding log member 152 upon the base log member 120 , with the end 112 of said base log member 120 extending laterally beyond the end of said first nonprotruding log member 152 , and affixing the first nonprotruding log member 152 to the base log member 120 ; placing the remaining log members 110 one at a time upon the log member 110 most recently affixed in place within the first wall 100 , the newly placed log member 110 being either a first protruding log member 150 or a first nonprotruding log member 152 , depending on and opposite to the log member 110 most recently affixed in place within the first wall 100 , such that the first protruding log members 150 and the first nonprotruding log members 152 are arranged in an alternating manner, and affixing the newly placed log member 110 to the log member 110 most recently affixed in place within the first wall 100 ; and placing the top log member 130 upon the log member 110 most recently affixed in place within the first wall 100 and affixing the top log member 130 to the most recently affixed log member 110 . The resulting first wall 100 will have the end of each first protruding log member 150 extending laterally beyond the end of each first nonprotruding log member 152 as described above. The next step is to prepare the log members 110 of the second wall 200 , by performing the following two sub-steps in any order: the second base log member 220 and half the number of second log members 240 are cut to desired lengths, such that the second base log member 220 and the second log members 240 have a suitable length to be utilized as second nonprotruding log members 252 ; and the remaining second log members 240 are cut to desired lengths, such that the remaining second log members 240 have a suitable length to be utilized as second protruding log members 250 . The next step is to assemble the second wall 200 . This is done in essentially the same manner as the first wall 100 is assembled. The resulting second wall 200 will have the end of each second protruding log member 250 extending laterally beyond the end of each second nonprotruding log member 252 as described above. In one embodiment the steps of preparing and assembling the first wall 100 may be performed after the steps of preparing and assembling the second wall 200 . If the preceding steps of the method for assembling the log structure of the present invention are performed at a location remote from the construction site, the next step is to transport the first and second walls 100 , 200 to the construction site. Transport of the walls may be made by flat bed truck, and loading and unloading of the walls onto the truck may be facilitated by the use of cranes. Other means for transporting the walls to the construction site are also contemplated within the scope of the claims. In the preferred embodiment, the first and second walls 100 , 200 will be prepared and assembled at a location remote from the construction site, such as at an assembly facility, to achieve efficiencies of prefabrication and mass production without concern for environmental conditions. The next step of the method is to position the first wall 100 as desired. The first wall 100 may be positioned by use of a crane. The next step is to position the second wall 200 as desired, adjacent to the first wall 100 . The second wall 200 may also be positioned by use of a crane. The positioning of the second wall 200 must result in the first protruding log members 150 of the first wall 100 being interleaved with the second protruding wall members of the second wall 200 . This forms the corner of the log structure. The next step is to affix the first wall 100 to the second wall 200 . The final step is to position a plug 170 within the notch 160 of each first protruding log member 150 of the first wall 100 . In one embodiment a further step is performed in which the plug 170 is fixedly attached within the notch 160 of each first protruding log member 150 by one or more mechanical fasteners. Alternatively, the plug 170 is fixedly attached by the use of an adhesive, such as wood glue or Liquid Nails®. An alternative method for constructing the log structure of the present invention comprises the same steps described above, with the following exceptions: the base log member 120 of the wall 100 is cut to a suitable length to be utilized as a first nonprotruding log member 152 , and the top log member 130 is cut to a desired length such that it has a suitable length to be utilized as either a first nonprotruding log member 152 or as a first protruding log member 150 , as determined by and opposite to the first log member 140 upon which it will be placed. The notches 160 are cut from the bottom portion 116 of the end 112 of each first protruding log member 150 . The second base log member 220 of the second wall 200 is cut to a suitable length to be utilized as a first protruding log member 150 . Modifications and variations can be made to the disclosed embodiments of the present invention and methods for constructing same without departing from the subject or spirit of the invention methods.

An improved structure, whereby the log structure is comprised of at least two adjacent walls mated to form a corner, with each wall constructed of logs laid horizontally upon each other, the logs alternating between protruding and nonprotruding logs, such that the ends of the protruding logs of the walls are interleaved, with the ends of the protruding logs of the first wall having notches cut from them to facilitate the mating of the first and second walls, and further comprising plugs to be inserted into the notches upon completion of assembly of the log structure, and a method for constructing same.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED APPLICATION The present application is a divisional application of U.S. Ser. No. 09/320,049, filed on May 26, 1999, which is incorporated herein by reference. FIELD OF THE INVENTION This invention relates to a method for embedding a multiplicity of discrete masses of material in a resinous coating on a sheet of metal in a coil coating system. More particularly, it relates to a one-pass system wherein the sheet is coated, the masses are embedded in the wet resinous coating, and the coating is dried. It further relates to a coil of metal decorated with said embedded masses. It relates particularly to the decoration of sheet metal so that it is useful as stock in the manufacture of metal roofing shingles simulating the appearance of traditional asphalt shingles. To that end, this invention relates to coil coated sheet metal to which the coating adheres sufficiently well to permit post-coating forming, molding, bending, and shaping of the metal without delamination or flaking of the coating. It further relates to coil coated sheet metal on which the resinous coating is resistant to ultra-violet radiation and the embedded masses are ultra-violet resistant color bodies of various hues. The surface of the coating may be substantially free of protrusions but at least a portion of the discrete masses may protrude above the surface of the coating to impart slip resistance to shingles made from the coated stock. BACKGROUND OF THE INVENTION Mineral covered asphalt sheets, by far the most commonly used shingles, are sold with guarantees of from 15 to 30 years depending on the weight per 100 square feet. The mineral granules are gradually dislodged by wind and rain to expose the asphalt binder to the destructive effects of ultra-violet light. Because of an increasing desire to replace the asphalt with a substrate that has a much longer useful life—on the order of about 60 to 80 years—the development of metal roofing shingles has become more and more important. STONECREST Steel Shingles having multilayered coatings are made from a combination of steel, aluminum, and zinc by Metal Works of Pittsburgh. The cost of simulating the appearance of mineral covered asphalt shingles by forming shingles from coated sheet metal stock may in part be reduced to a commercially acceptable level by reducing the number of coating steps and the corresponding time. In a conventional coil coating system, paint is picked up by a roller rotating in a paint pan and transferred to an applicator roller and a coil of sheet metal is uncoiled as the metal is pulled through a series of rollers, one or more of which is a paint applicator roller, at up to 1000 feet per minute. The coated metal is then passed through an oven for drying or curing and coiled again. The sheet is passed through the system each time a separate coating layer is to be applied. To the knowledge of the instant inventors, none of the many patents directed to coil coating teach the coating of a face of sheet metal with a resinous composition and embedment of a second coating material in the wet surface of that coating in a single pass of the metal through a coil coating system. Several patents teach the coating of moving flexible substrates with two materials. The principal substrates are sheets of asphalt, PVC and fabric but metal is often mentioned as a potential substrate. U.S. Pat. No. 5,827,608, for example, teaches the electrostatic fluidized bed application of a coating powder (e.g., a blend of two distinct, chemically incompatible resins) onto the underside of a vinyl sheet being drawn from a coil at about 4 feet per minute, heating the powder and pressing it to fuse and bond it to the vinyl, and rewinding the coated sheet into a coil. SUMMARY OF THE INVENTION It is an object of this invention, therefore, to provide a coil of sheet metal having a resinous coating on one face and a multiplicity of discrete masses of material embedded in said coating. It is another object of this invention to provide metal roofing shingle stock having a resinous coating on one face and a multiplicity of discrete masses of material embedded in said coating. It is a related object of this invention to provide metal roofing shingle stock having a multiplicity of discrete color bodies embedded in a resinous coating. It is another object of this invention to provide a method for coating one face of sheet metal with a resinous composition and embedding a particulate coating material in the wet surface of that coating during one pass of the metal through a coil coating system. These and other objects of this invention which will become apparent from the appended drawings and the following description are achieved in one embodiment of the invention by a method for coating sheet metal which comprises unwinding the sheet metal from a coil thereof and directing the sheet metal through a series of rollers, one or more of which is an applicator roller, placing a liquid resinous coating composition in a paint pan, picking up said resinous coating composition on a rotating roller in the pan and and transferring it to an applicator roller; thenceforth transferring it as a protective coating to the moving sheet metal, distributing discrete masses of material uniformly on the liquid or at least plastic protective coating and causing at least a portion of them to submerge at least partially in said protective coating, drying said protective coating, and rewinding the coated metal sheet into a take-up coil. The method of this invention is characterized by distributing the discrete masses to form a discontinuous field coextensive with the area of the coating, thus simulating the appearance of conventional asphalt-based shingles. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic drawing of a coil coating line suitable for the distribution of color bodies on wet resinous coated sheet metal moving on the line. FIG. 1 a is perspective view of one embodiment of the particle distributor of FIG. 1 . FIG. 1 b is a perspective view of another embodiment of the particle distributor of FIG. 1 . FIG. 2 is a schematic drawing of a flame spray system for projecting fused particles onto wet resinous coated sheet metal moving on a coil coating line. FIG. 3 is a plan view, partially broken away, of a flame spray gun for the system of FIG. 2 . FIG. 4 is a schematic drawing of a coil coating line suitable for the distribution of ceramic granules on wet resinous coated sheet metal and the interleaving of a backing sheet with the coated sheet metal as it is rewound on a take up coil. DETAILED DESCRIPTION OF THE INVENTION As used herein, substantially means largely if not wholly that which is specified but so close that the difference is insignificant. In the coil coating operation of this invention, substantially the full expanse of an aluminum or galvanized steel sheet is coated as it travels at 250-1000 feet per minute. Hot dipped galvanized (HDG) steel is suitable for low cost operations but a zinc/aluminum alloy such as that sold under the trademark GALVALUME® is preferred for its corrosion resistance. Aluminum is more preferred when cost is not a limiting factor. Pretreatment of the metal is important for increased corrosion protection and adhesion of the coatings. Typical conversion coating compositions used in the pretreatment include those sold under the trademarks BONDERITE® 1303 or 1310 for the GALVALUME® metal, and BETZ® 1500 and Morton's FIRST COAT® for aluminum. For optimum adhesion and corrosion resistance, it is preferable that the metal is coated with a primer over the conversion coating. Suitable primers for this invention include epoxy, acrylic, polyester, or polyurethane resins as binders. U.S. Pat. No. 5,001,173 is incorporated herein by reference for its description of primers that are suitable here. The primer thickness may be from 0.2 mil to 1.6 mils, preferably about 0.8 mil or more. Flexible primers are preferred when the coated metal stock is to be post formed in the manufacture of a roofing shingle. Greater flexibility may be achieved by the use of thick film primers such as are described in U.S. Pat. No. 5,688,598, which is incorporated herein by reference, and are available from Morton International, Inc. The peak metal temperature (PMT) for the curing of the primer is that recommended by the supplier but it is usually in the range of 435-465° F. (about 225-240° C.). Pigments such as those described below in regard to the topcoat and embedded particles are used to impart ultraviolet light resistance to the primers also. For the purposes of this invention, the liquid resinous coating composition preferably comprises an ultraviolet light resistant pigment and a thermoplastic or thermosettable fluorocarbon resin. As used herein, a fluorocarbon resin is a homopolymer of vinyl fluoride or vinylidene fluoride or a copolymer of either of those two monomers with one another and/or other copolymerizable, fluorine-containing monomers such as chlorotrifluoroethylene, tetrafluoroethylene and hexafluoroethylene. Fluorocarbon resins are available under the trademarks KYNAR® and HYLAR®. Fluorocarbon resins and coating compositions comprising a fluorocarbon and an acrylate or methacrylate monomer or mixture of the two are described in U.S. Pat. No. 5,185,403, which is incorporated herein by reference. Coating compositions particularly suitable for the purposes of this invention are available under the trademark FLUOROCERAM®. A mixture of a vinylidene fluoride/chlorotrifluoroethylene copolymer (55:45 by weight percent) and methylmethacrylate (MMA) wherein the weight ratio of the MMA to the copolymer is from about 2:1 to about 5:1 is also suitable. A fluoropolymer particularly suited to the top coating over the conversion coating on unprimed sheet metal is described by Yamabe et al in U.S. Pat. No. 4,345,057. Commercially available fluoropolymer resins which are believed to be substantially similar to those described in the Yamabe et al patent include those sold under the trademarks ICI 302, ICI 504, and ICI 916. For the purposes of this invention, the word “drying” is used to mean the solidification of molten material and the curing of thermosettable resins as well as the evaporation of solvents. The thickness of the liquid resinous coating is such that it forms a 0.5 to 1.0 mil thick dry coating, preferably one that is about 0.8 mil or greater, to provide sufficient holding power for the discrete masses of submerged particulate material. It is preferable that the liquid resinous coating is still wet so as to promote the submergence and bonding of the discrete masses but a baked coating which is not fully cured may serve when softened as a plastic medium for the submergence of such particulate material. Thus, for the purposes of this invention, the term “liquid resinous coating” is defined to include a coating which is sufficiently plastic to be susceptible to penetration by a particulate material under the conditions of this invention without otherwise fracturing the coating. When the particulate material is a resin, it is suitable for the purposes of this invention to fuse the resin and cause it to merge with the protective coating. In some cases, such as when the particulate material is a thermosettable coating powder or an uncured thermosettable resin in some other form such as a chip, concurrent curing of the liquid protective coating and the particulate material may take place. The curing temperature for the fluoropolymers is usually at a PMT in the range of 465-480° F. (about 240-280° C.). The discrete masses of particulate material must, therefore, be able to withstand such high temperatures. As used herein, the term “discrete masses” means individual particles of material as well as masses of particles such as are used in powder gravure coating processes and includes discrete color bodies as well as colorless particles. Pigmented particulate minerals and resins in the form of granules, beads, vesiculated beads, pellets, flakes, platelets, cylinders, coating powders, and chips such as coating powder precursor chips are suitable as discrete color bodies for the purposes of this invention. The minerals include glass, quartz, mica, pebbles, and ceramics. The particulate resins include polyesters, acrylics, nylons, polyurethanes, polycarbonates, solid fluorocarbon resins, and solid mixtures of a fluorocarbon and a polymer or copolymer of the acrylate or methacrylate monomers as described above in regard to the liquid resinous coating. Amorphous acrylic/styrene/acrylonitrile resins sold by General Electric under its GELOY® trademark, noted for durability in weather related environments, are suitable for the purposes of this invention. The preferred granules are aggregates sold under the trademark COLORQUARTZ® by 3M. The preferred spherical S grade granule has a particle size range of 20 to 70 (U.S. Sieve), which is about 8 to 30 mils. The resin particles are likewise about 8 mils or larger. Chips intended to be ground for conversion into coating powders, referred to hereinabove as coating powder precursor chips, are themselves quite suitable as the discrete color bodies for this invention. Simulation of the asphalt shingle appearance may be achieved by contiguous discrete masses of different colors, by spacing of the masses by at least as much as the individual particle sizes, or both. The pigments impart ultraviolet light resistance to the primer, the topcoat and the embedded color bodies and yield aesthetic effects. Most of the UV resistant pigments are metal oxides; examples of such include those sold as DUPONT Ti Pure R-960, COOKSON KROLOR KY-795 Med. Yellow (2), COOKSON KROLOR KY-281D Lt. Yellow (2), COOKSON KROLOR RKO 786D Orange (2), COOKSON KROLOR RKO 789D Orange (2), SHEPHERD # 1, SHEPHERD Yellow #29, ISHIHARA Titanium Golden, FERRO V9118 Bright Golden Yellow, Golden Brown #19, SHEPHERD #195 Yellow, HARCROSS Red Oxide R-2199, HARCROSS KROMA Red Oxide RO-8097, HARCROSS KROMA Red Oxide RO-4097, G-MN chrome oxide, and FERRO V-302. COLUMBIA RAVEN 1040 carbon black and the COOKSON A-150D laked black exemplify the non-metal oxide pigments which impart UV resistance to the top coat and embedded particles. A phthalocycanine green pigment sold as MONASTRAL Green GT-751D (5) is a UV resistant organometal pigment suitable for the purposes of this invention. The amount of pigment used in each situation will vary according to the depth of coloration and UV resistance desired and according to the properties of the various pigments chosen. The discrete masses of material embedded in the protective top coating may be made cellular in structure by the incorporation of blowing agents in their formulations in amounts such as are just sufficient to cause expansion of the particles while preferably avoiding perforation of the particles at temperatures up to and including 280° C.(˜480° F.). An amount ranging from about 0.1 to about 3% by weight of the resin is satisfactory, the actual amount depending upon the particular foaming agent, the particular resin, the coating temperature, and the expansion desired. Blowing agents such as p-toluene sulfonyl hydrazide, 2,2′-azobis(isobutyronitrile), and azocarbonamide are suitable. EMBODIMENTS OF THE INVENTION In FIG. 1, the coil 10 of sheet metal 11 is operatively disposed on the unwinding device 12 , from which the sheet travels through a pre-cleaning unit (not shown) and the first accumulator 13 of a conventional coil coating line. After leaving the first accumulator, the metal sheet 11 travels around rolls 14 and 15 to contact the applicator roll 16 of the pretreatment coater and through the drier 17 before it passes through the prime coater 18 , the backing coater 18 a , and drier 19 . The sheet 11 is then passed through the applicator 20 where the liquid resinous coating composition 21 in the pan 22 is picked up by the roll 23 , transferred to the applicator roll 24 , and deposited on the metal as the wet top coat 25 . The wet coated metal is then passed under the distributor 26 from which discrete masses 27 of organic or inorganic material are distributed uniformly on the wet resin. The coated sheet metal then travels through the oven 28 , a set of pressure rollers 29 when necessary for the embedment of the masses 27 , a quench unit (not shown), and the second accumulator 30 before it is taken up again on the rewind coil 31 . A particular embodiment of the distributor 26 of FIG. 1 is illustrated in FIG. 1 a by the combination of the hopper 32 which feeds particulate matter into the multiplicity of pockets 34 engraved in the surface of the cylindrical roll 36 which rotates at a velocity matching the linear velocity of the metal sheet passing through the coil coating line. The engraved area of the roll corresponds to the width of the top-coated metal sheet 25 and the pockets are spaced apart to achieve the desired density of particulate matter on the wet topcoat. A static mixer available from 3M is particularly suitable as the hopper 32 for feeding granules to the roll 36 . Another embodiment of the invention is shown in FIG. 1 b , wherein the discrete masses 27 are gravity fed from the hopper 40 onto the motorized continuous conveyor belt 42 , which is disposed a short distance above the top-coated metal sheet 25 . The belt 42 travels in the same direction and at the same linear velocity as the metal sheet as the masses 27 drop onto the sheet 25 . The sheet and the conveyor belt 42 are disposed for a short distance within the trough 43 which collects any discrete masses 27 which fall from the conveyor but miss or fall off of the sheet. Such discrete masses thus collected in the trough may be returned to the hopper 40 by conventional means such as a blower situated within tubing connecting a chute in the trough and the hopper. In another embodiment of this invention, the distributor 26 of the coil coating line of FIG. 1 is replaced by the flame sprayer 44 shown in FIG. 2 . Here, the topcoat on the metal sheet 25 is a thermoplastic resin which retains sufficient heat as it the leaves the oven 45 to remain soft. Particles of a thermoplastic resin are fed into the sprayer 44 disposed adjacent the ascending sheet 25 . The sprayer instantly heats the particles to a molten or plastic state and propels the particles onto the surface of the still soft thermoplastic coating on the sheet 25 at a speed of about 30 to 60 feet per second, forming flattened plastic particles called splats which range from 0.5 mil to 4 mils in diameter. The size of the particles being fed into the sprayer 44 , the distance from the sprayer to the surface of the top-coated sheet 25 , and the rate of feed are controlled so that the flattened particles remain as uniformly distributed discrete masses in the top coat over substantially the full expanse of the coated metal sheet 25 . A plurality of flame spray guns 46 , each spraying particles of a different color, may be mounted in the flame sprayer 44 so as to form a multiplicity of splats over all or some lesser desired portion of the sheet metal surface. Flame spray gun 46 as illustrated in FIG. 3 has a body 47 with supply channels 48 , 49 , and 50 for air, fuel gas, and a fluidized coating powder, respectively. Channel 50 communicates with a fluidizing chamber (not shown) from which a coating powder suspended in a stream of compressed air is pushed intermittently into the flame spray gun 46 by rapidly opening and closing a valve in a supply line carrying a stream of compressed air and coating powder into the fluidizing chamber. The outlet of the powder channel is axially disposed within the gun mouthpiece 51 and combustion gas outlet nozzles 52 are situated in the mouthpiece 51 at equal distances around an imaginary circle concentric with the powder channel 50 . The amounts of air and gas are regulated by valves 53 and 54 . The air passes through the ejectors 55 creating a partial vacuum in the fuel gas channel 49 and drawing the gas into the mixing chambers 56 . The combustible mixture flows through the mouthpiece nozzles 52 and burns. The powder particles are heated to a molten state as they pass quickly through the flame. As illustrated in FIG. 4, when discrete masses 27 of FIG. 1 such as ceramic granules or the like protrude above the resinous top coat, a removable backer sheet 60 is drawn from the coil 61 and interleaved with the granule covered metal sheet 62 as it is rewound into the coil 63 in order to protect the underside of the sheet metal. The backer sheet 60 may be made of a foamed material such as polystyrene or poly (vinyl chloride).

This invention relates to a method for embedding a multiplicity of discrete masses of material in a resinous coating on a sheet of metal in a coil coating system. The sheet is coated, the masses are embedded in the wet resinous coating, and the coating is dried in a one-pass system. The resinous coating and the embedded masses are preferably resistant to ultra-violet radiation. The wet resinous coating, therefore, is preferably a liquid fluorocarbon resin. The discrete masses comprise pigmented particulate minerals and resins in the form of granules, beads, vesiculated beads, pellets, flakes, platelets, cylinders, coating powders, and coating powder precursor chips. The minerals include glass, quartz, mica, pebbles, and ceramics. The particulate resins include polyesters, acrylics, nylons, polyurethanes, polycarbonates, solid fluorocarbon resins, and solid mixtures of a fluorocarbon resin and an acrylate or methacrylate polymer or copolymer. Sheet metal decorated in such a manner is useful as stock in the manufacture of metal roofing shingles simulating the appearance of traditional asphalt shingles.

You are an expert at summarizing long articles. Proceed to summarize the following text: This application claims benefit of Ser. No. 60/122,802, filed Mar. 3, 1999 BACKGROUND OF THE INVENTION This invention relation to a system for progressively placing the roof structure in place as the tunnel is being bored with a tunnel boring machine (TBM). This invention will be found to be most effectively used on open or main beam type TBM's in situations where a tunnel is being bored in a rock strata wherein the roof is somewhat unstable. When boring a tunnel in subterranean rock, the TBM's of the present invention utilize a rotating boring head to spall and crush a rockface by exerting pressure on the rockface by means of a series of cutting elements mounted on a rotating boring head. As the rockface is gradually eroded, the forward portion of the TBM on which the boring wheel is mounted moves ahead while thrusting against a gripper system which is wedged into the previously formed tunnel. The thrust system provides the required force to crush the rock at the rockface. Because some tunnels must be driven into rock which is unstable or becomes unstable when subjected to the forces exerted on the rockface by the excavation, it is not unusual to have fractures in the strata surrounding the tunnel itself. These fractures produce discrete pieces of rock which can fall into the tunnel opening if they are not held in place after the TBM moves forward. If the fractures occur in the bottom or sides of the tunnel, it is of little consequence. However, if the strata through which the tunnel is being bored is of the right type and consistency, rock fractures occurring in the tunnel roof may allow portions of the roof to fall which can have serious consequences for the tunneling operation. Falling rock from the tunnel roof may endanger tunnel workers and the tunneling machinery but the falling rock creates an uncontrolled opening above the tunnel and generally disrupts the excavation process. Some TBM's have employed a shield in the form of a partial cylinder which fits close to the most recently formed tunnel roof just behind the boring head of the TBM. The shield is sometimes provided with some means or other to move the shield vertically so as to be able to engage or remain clear of the tunnel roof. The shield provides the protective structure to prevent falling rock from injuring TBM operating personnel but does not provide a permanent support for the tunnel roof. As the shield moves forward with the TBM, it uncovers the tunnel roof which if not otherwise supported, can fall. It is not unusual to encounter conditions where falling rock from the roof of a newly formed tunnel can present such a hazardous situation that the boring operation must be halted while a temporary roof is placed in the newly formed tunnel. Arc shaped cylindrical segments of a suitable material (usually steel) may be bolted to the roof by rock bolts. If the TBM shield has a fingered shield which will permit the installation of rock bolts between the shield fingers, metallic roof ribs may be fastened to the roof of the tunnel while the shield is yet above the rib. Of course, the exposed ends of the rock bolts which protrude between the fingers of the TBM shield may present a problem if for some reason the fingers of the TBM shield move laterally, as may well happen during a steering correction operation of the TBM. Rib systems placed with finger shields, though providing support for the tunnel roof at periodic spaced intervals, has the shortcoming of not providing support for the tunnel roof between the placed ribs. Because of the shape of the shield and its extending fingers, a large proportion of the tunnel roof is obscured by the extending fingers and if an attempt is made to install timbers etc. between the fingers of the shield, the previously installed rock bolts prevent the insertion of such roof support members between the extending shield fingers. At times wire mesh (similar to chain link fence or concrete reinforcing mesh) has been used between the roof ribs and the fingers of the shield to prevent rock fall from the exposed portion of the tunnel roof between the shield and the roof rib, but this method of support suffers from the lack of rigidity of the mesh between the shield and the last installed rib. The mesh tends to sag as rock drops from the roof; this sagging mesh not only protrudes into the tunnel destroying the tunnel profile, but serious deterioration of the roof may occur above the mesh. Before applicants' instant invention, the only effective method previously known for the installation of longitudinally extending support members between the roof ribs was to install such members after the finger shield had moved onward away from the ribs and exposed the whole roof. However, if loose roof rock is present above the finger shield, it will usually fall before or during installation of the longitudinal support members. The potential for falling rock endangers personnel and hinders the construction process. When boring through other types of strata, problems relating to falling debris from the roof of the tunnel may occur due to the disturbance caused by the TBM's boring activity and this invention may be efficiently employed to provide a safe environment for the tunneling personnel who must perform operations in the tunnel to bring the tunnel construction to completion. SUMMARY OF THE INVENTION The TBM of this invention is provided with a shield which comprises a series of hollow rectangular tubes arranged in an arc (akin to slats in a lobster trap) which are fastened together and mounted on a framework of curved beams so as to extend longitudinally along the tunnel axis and have substantially the same surface curvature as the tunnel roof. The tubes extend from a point immediately behind the TBM boring head to a point where the support of the tunnel roof is completed. The framework is attached to the TBM in such a manner that the curved upper surface formed by the tubes forming the shield may be held against the tunnel roof. The height of the shield is adjustable within predetermined limits. The tubes forming the shield are of a length required to extend from a point just behind the cutter head to a support installation point and are of such size as to accommodate the elongated members which will provide the primary tunnel roof lining. Thus, the “shield” comprising a plurality of hollow tubes is “loaded” preferably with timber members, such that the ends of the timber pieces protrude from the hollow tubes behind the shield so that they may be fastened by some means or other to the tunnel roof. The tubes are intentionally made to be somewhat larger in cross section than the timber lagging members which are inserted inside the tubes so that the lagging timbers enjoy a “sloppy” fit. As the boring machine moves into the rock, more of the timber members are exposed almost as if in an extrusion operation. Metallic or other curved or ring support beams may be subsequently installed by the tunnel building personnel as the machine moves away from the last installed roof beam. The ends of the timber lagging members are intentionally staggered lengthwise along the tunnel roof, so that at no time does a pair of coincident joints occur in adjacent rows at the lagging members. Each time a tube is emptied of its lagging timber, a new lagging timber is pushed into the empty tube to be subsequently fed out as the TBM advances. This causes staggered laps in the timber lagging members forming the completed roof. PERTINENT PRIOR ART U.S. Pat. No. 3,989,302 issued Nov. 2, 1976. This patent describes a TBM having a shield comprising a series of “T” shaped members mounted on a curved beam structure. Lagging members are installed between the T shaped members such as 58, 59 and the supporting beams such as 30 and 31. The lagging members (17, 48, etc.) are installed in the space between support beams 30, 31 and the T shaped members of the shield by lowering the support beams 30, 31 by means of cylinder actuators 36, 37 to provide the necessary space to insert lagging members 17, 48, etc. TBM's must be stopped at intervals to permit the “mined” material produced by the boring head to be removed, and it is during this time that the support beams 31, 32 may be lowered to permit the insertion of new lagging members 17, 48, etc. in the space between T members 17, 48, etc. and support beams 30, 31. If, however, the TBM has moved a sufficient distance that a substantial portion of the tunnel roof has not been lagged due to the progress made in the boring operation, it may be necessary to halt the boring operation to install the lagging members in the shield. Additionally, once the lagging members 17, 48, etc. have been installed in between the T shaped shield members 58, 59; 60, 61; etc., there is little opportunity to install rock bolts between the T shaped shield members. After the shield has left the lagging members 17, 48, etc. exposed a support system must be installed to hold the lagging members against the roof. The patent describes the use of ring beams 23, 24, etc. which are subsequently installed, and wedges such as 79 are used to “jack” the lagging members against the tunnel roof. Other methods of securing the lagging members 17, 48, etc. to the roof i.e. rock bolts are discussed in the patent but these are almost impossible to install while the TBM shield is between the lagging members and the tunnel roof. Lastly, the above U.S. Patent makes no suggestion of staggering the joints in the lagging members; all the lagging members have been purposely manufactured to have the same length so as to be supported at each end by ring supports 23, 24, etc. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram of a prior art finger shield and associated rock stabilizing apparatus. FIG. 2 shows a section of the tubular shield of this invention. FIG. 3 is a sectional view of tunnel showing the location of the tubular roof shield in the tunnel. FIG. 4 shows a similar structure to FIG. 3 but includes part of the tunnel boring machine. FIG. 5 is a sectional view of the tunnel having lagging installed. FIG. 6 is a view along section C—C of FIG. 5 . DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows a partial view of a TBM shield 10 of the prior art. The shield comprises a steel arch 12 which is attached to the TBM so that the shield may be moved up and down by means of hydraulic cylinders to clear or contact the tunnel roof. The trailing portion of the shield 10 comprises a series of elongated substantially parallel fingers 14 , 16 , 18 , 20 , 22 . Tunnel personnel are able to install an arched rib 24 beneath the shield fingers by means of rock bolts 26 which pass through clearance holes 28 in rib 24 and penetrate deeply into the roof rock. (Note that rock bolts 26 are situated in the only space where it would be desirable to install longitudinal support members.) As the TBM moves forward, the fingers will gradually pull away from rib 24 and the rib must be drawn up against the tunnel roof to secure any loose rock in place. Ribs such as 24 may have to be installed at frequent intervals in tunnels exhibiting roof instability. At times during a tunneling operation the finger 14 - 22 are required to be moved in a lateral direction instead of the axial direction usually followed by the TBM. During such operations, the fingers 14 - 22 tend to shear the rock bolts 26 or fracture fingers 14 - 22 . This causes substantial inconvenience to the tunnel boring personnel who are responsible for the integrity of the TBM and the roof support structure. FIG. 2 shows a portion of the novel tunnel shield 30 of this invention. A series of hollow rectangular tubes 50 , 52 , 54 , 56 are mounted on an arched framework on a TBM. Tubes 50 , 52 and 54 are shown having lagging members 58 , 60 , 62 protruding from the interior of tubes 50 , 52 , etc. FIG. 3 shows a TBM shield 30 comprising tubular members 50 , 52 , 54 , 56 as partially shown in FIG. 2 . The tubular members are mounted on arched supports 70 on which the tubes are fastened by welding or other suitable fastening means. Front support 72 is pivoted at pivot 74 and support 76 and provides rigidity to the frame structure carrying the tubes 50 - 56 . An inflatable air bag device is mounted beneath the tubular shield 30 at point “X” to apply a constant upward pressure on shield 40 . It is important that pressure device is of a compliant nature so that if the TBM is suddenly jostled by some unexpected force during an excavating operation, the shield 30 may be allowed some freedom to move so as not to bend tubes 50 , 52 , etc. Lagging members 58 , 60 , 62 , etc. are shown protruding from tubes 50 , 52 , 54 , etc. and are subsequently fastened to the tunnel roof 80 by means of ribs 66 , and roof rock bolts 68 . (If full rings are being used to support the lagging members, it may not be necessary to use rock bolts.) As the lagging members such as 58 , 60 and 62 are “extruded” from the rectangular tubes such as 50 , 52 and 54 , the ribs such as 66 are bolted in place (by use of rock bolts 68 ) against the lagging members 58 , 60 , etc. to secure the lagging members firmly against the roof of the tunnel. The tubes 50 , 52 and 54 support the lagging members at their forward end; the ribs 66 supply the anchoring mechanism in the area where the tunnel has been driven. A space shown as “D” between the end of the shield of the TBM and rib 66 is bridged by lagging members such as 58 , 60 and 62 so that workers may safely work in this area to install ring supports such as 66 . If the TBM should move so that the tubes 50 , 52 and 54 , etc. move laterally (or rotate about its longitudinal axis), the lagging members 58 - 62 merely swing from the end of shield 40 and pivot from the last rib installed in the roof. As the lagging members are fed out of the tubes, such as 50 - 54 , they must be replenished in the rectangular tubes 50 - 54 . Usually, the lagging members are interspersed in such a manner that the joints are staggered along the mine roof. Thus, periodically a new lagging member must be installed in the tubes of the shield, and this may be done while the TBM is operating; it is not necessary to lower the shield to insert a new lagging member. It may be convenient to overlap the ends of the lagging members at the joint. FIG. 4 shows a similar view to that shown in FIG. 3 except that parts of the TBM are present in FIG. 4 . Front support lugs 80 used to support the forward portion of the roof shield 30 are shown. Rear support 82 is supported from the main beam 84 of the TM. A plateau is formed at 86 by member 88 which is supported by member 82 and intermediate support 90 . The airbag 92 provides a resilient support for the rearmost portion of shield 30 and is easily adjusted to suit the condition existing at the boring site in the tunnel. The presence of the air bag 92 supplies the upward force necessary for holding shield 30 against the roof of the tunnel. FIG. 5 shows a cross section of tunnel which has had a lining installed during a tunneling operation. Bolts 68 secure arch support member 66 in place to hold the lagging members such as 50 - 54 against roof 81 . FIG. 6 shows a view of the tunnel roof taken along section C—C of FIG. 5 . The extruded lagging members such as 50 - 54 are all permanently located under ribs 66 held firmly by rock bolts such as 68 . The advantages of applicant's device are many. There is no need to install rock bolts in the area of the shield (as shown in FIG. 1) because the lagging members 50 - 54 are supported by the tubes 50 , 54 , at the TBM end of the “bridge” formed between the TBM shield 30 and the latest rib such as 66 installed in the tunnel. Thus, there are no rock bolts to fracture or cause damage to the shield of the machine during any unexpected lateral or twisting motion of the shield 30 . The lagging members are deliberately chosen to be somewhat flexible so as to allow substantial motion of shield 30 without breakage to shield 30 or the lagging members because the lagging members are flexible. Lagging members may be installed in shield while the TBM is operating. The ribs are installed against the lagging members 50 , 54 , etc. at some distance behind the shield of the TBM so that ribs 66 need to be tightened only once against the lagging members 50 - 54 , etc. The preferred material for lagging is lumber, such as building grade spruce 2″×4″, 1″×2″, 2″×3″ depending on the nature of the fractures occurring in the tunnel roof. In some instances, heavier timbers may be required. The size of timber lagging will depend on the stability of the rock formation and the diameter of the tunnel being bored. It may be possible to use plastic or steel lagging in tubes which are other than of a rectangular cross section. Those skilled in the art, will immediately know the size of lagging required for a safe and secure primary tunnel lining for the tunneling conditions encountered. This invention functions best when the timber lagging members are given a generous amount of clearance in the hollow tubes of the shield. This invention will function in most adverse tunneling conditions to protect tunnel personnel and tunnel machinery during tunneling operations. Loose rock that falls on shield 30 is held first by the shield and then by the lagging members 50 - 54 etc. Rock pieces are prevented from falling on the tunnel workers or the tunneling machinery. Because of the continuous barrier created by the shield 30 and the lagging members 50 - 54 etc., consistent excavation of the tunnel results, and productivity gains will result during the tunnel excavation. After the excavation has been completed, it is not unusual to undertake additional work to “line” or “finish” the tunnel. In prior art structures, situations have been encountered where concrete must be pushed upwardly into caverns left by the falling roof rocks. If a wire mesh has been employed to stabilize the tunnel roof, it may have sagged in areas of roof instability and protrude into the tunnel destroying the circular profile of the tunnel. Considerable time and energy must be expended to remove the “intrusions” before lining of the tunnel takes place. Problems such as those outlined above are eliminated with the present invention. Although alternatives will be apparent after reading this specification, the applicant wishes the scope of this invention to be limited only to the breadth of the following claims.

A primary support for a tunnel roof comprising elongated lagging members which are “extruded” from tubes forming a shield for a tunnel boring machine. The lagging is inserted into the tubes at different times so as to avoid having the ends of adjacent lagging members coincide. As the tunneling machine progresses in the direction of boring, the lagging members emerge from the shield tubes to form a primary tunnel roof lining. Ring beams or arc beams may be installed as required by rock bolts or other fastening devices.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Patent Application No. 61/403,837 filed Sep. 21, 2010 and U.S. Provisional Patent Application No. 61/572,424 filed Jul. 15, 2011 the contents of which are hereby incorporated by reference. TECHNICAL FIELD [0002] This description relates generally to window shutters and more specifically relates to window shutters having features to improve the performance, durability and operation of the shutters and also to substantially reduce light infiltration between the shutter frame and louvers, and other openings often inherent in shutter construction. BACKGROUND [0003] Various types of interior window treatments are utilized in both residential and commercial buildings. One such widely used and accepted window treatment is the shutter. Shutters are popular because of their pleasing aesthetic appearance, versatility, adjustability and other functional advantages. [0004] One functional advantage of shutters is that the shutters can be provided with louvers which can be positioned or adjusted to change the desired light level and also to deflect light or reduce glare. Shutters are also insulative and assist in reducing the heat load transfer to the interior area through a window opening. Shutters are manufactured to fit window openings having a wide variety of sizes and shapes. [0005] In the past, shutters have been made primarily of wood. Modern shutters are increasingly fabricated from more durable materials such as polymeric materials or a combination of composite materials such as wood and synthetic polymers. Common materials are polyvinyl chloride, polystyrene, polyurethane, polypropylene and composites of these materials. However wood shutters typically are quite rigid, and components such as louvers when made from polymeric materials alone may sag or bend, as they lack the rigidity of wood. [0006] Fabrication of shutter components using various synthetic and engineered materials makes the manufacturing technique more efficient as many of the components can be extruded whereas in the past these components, when made of wood, required multiple operations such as milling, planing, shaping drilling and routing in the assembly process. Despite the materials used to construct shutters, the components used and their assembly have not changed a lot. In a shutter there are often many cracks, or openings where light may come through. Thus typical shutters may not completely block light and must often be used in conjunction with curtains or the like to completely block light from entering a room. [0007] Accordingly, there exists a need for a shutter with improved light blocking features. Also a polymeric shutter louver with improved rigidity would be useful. SUMMARY [0008] The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later. [0009] The present example provides a window shutter assembly having an exterior frame with vertical sides and horizontal top and bottom members which supports at least one louver panel with vertical stiles and top and bottom horizontal rails. The louver panel is hinged to the exterior frame so that the louver panel may open or close. A light blocking material may be included to prevent light from infiltrating space which may be present between the louver panel and frame. The louver panel comprises a plurality of louvers are arranged in parallel fashion and joined at opposite ends to the edges of the vertical stiles. The spaces between the louvers and stiles may also incorporate a light blocking material. The position of the louvers is established by a control rod or tilt rod connected to the individual louvers. The exterior frame which extends around the louver panels has a generally L-shaped, cross-sectional configuration to receive the louver panel and has a stop surface against which the louvers abut in a closed position. [0010] With the present invention, a light-blocking seal is provided at various locations within the shutter assembly to substantially block light infiltration. In one embodiment, the light-blocking seal is in the form of a flexible member such as a flap integrally extruded as part of the shutter component, such as part of the exterior frame, or on the edge of the shutter panel stile to block light when the shutter panel is closed. The light-blocking seal is a flexible polymeric flap co-extruded with the stop surface of the exterior frame which seals areas between the shutter components which may otherwise allow light infiltration. The seal may also take other shapes such as round, oval or even semi-spherical. [0011] The present invention can also eliminates the need for the structural divider rail that is common in larger louver panels such as those over 5 feet in height. Normally shutter panels of this size and larger have a fixed horizontal structural divider extending between the vertical stiles for structural integrity. A tight louver screw replaces dividers for taller shutter panels. The louver screw assembly includes a screw which extends from a recess in the vertical stile in which the head of the screw is located. The threaded portion of the screw extends through a bore into the adjacent louver panel. A thrust washer is interposed between the head of the screw and the bottom of the recess. Low friction washers of nylon or other material are preferably positioned on opposite sides of the thrust washer. The thrust washer supports rotation of the screws and the attached louver as a unit to provide structural integrity to the assembly maintaining the spacing between the vertical stiles, minimizing the tendency of the screw to “strip” from the louver ends. [0012] In yet another embodiment of the present invention, a plurality of tension-control pins may be placed at selected locations between the stiles and the louvers, typically in about one-third of the locations. The tension-control pins secure the louvers and reduce wear by preventing the weight of the tilt rod from causing the louvers to pivot, particularly after wear has occurred. [0013] Light-blocking around the various spaces described above may be accomplished is in the form of a strip of fibrous or pile, brush-like material having a generally round, T cross-sectional or other equivalent shape. The base of the T-shaped, flexible fibrous light-blocking strip is secured in suitable locations where light might infiltrate, such as in grooves routed in the edges of the vertical stiles and horizontal rails, as well as in the horizontal and vertical frame components. [0014] Another light-blocking feature is the provision of interlocking or inter-engaging sections on the edges of the louvers. When the louvers are fully closed, these sections abut similar sections either on adjacent louvers or on an edge of a rail in interlocking or inter-engaging fashion to block light. [0015] The present invention also provides an enhanced construction in which the individual louvers are a synthetic or composite material and are reinforced to further resist warpage and deformation due to wear, tear and environmental conditions. [0016] Many of the attendant features will be more readily appreciated as the same becomes better understood by reference to the following detailed description considered in connection with the accompanying drawings. DESCRIPTION OF THE DRAWINGS [0017] The present description will be better understood from the following detailed description read in light of the accompanying drawings, wherein: [0018] FIG. 1 is a partial perspective view of a representative shutter assembly according to the present invention showing the exterior frame and an interior louver panel hinged to the exterior frame. [0019] FIG. 2 shows light blocking material disposed between the frame and shutter panel. [0020] FIG. 3 shows how light may be blocked from entering gaps between the shutter frame and wall. [0021] FIG. 4 shows how light may be blocked from entering gaps that may be present between louvers and an aperture in the shutter panel in which the louvers are disposed. [0022] FIG. 5 is a perspective view of a section of the exterior frame showing a co-extruded, light-blocking seal. [0023] FIG. 6 is a cross-sectional view of a section of an exterior shutter frame as seen in FIG. 2 provided with another embodiment of the co-extruded light-blocking seal. [0024] FIG. 7 is an enlarged detail view of a louver stile and attached louver broken away to show the installation of a tight louver screw to provide structural integrity in larger shutter assemblies not having a divider panel. [0025] FIG. 8 is a detail view of a shutter stile and an adjacent louver broken away showing the installation of a tension-control pins placed between the stile and louver at selected locations to frictionally secure the louvers to prevent the tilt rod from causing the louvers to pivot. [0026] FIG. 9 is a partial perspective view representative of a shutter frame section including a light seal, and an alternative example of alight seal for engaging the rails or stiles of the louver panel. [0027] FIG. 10 is a cross-sectional view of an extruded louver having an embedded reinforcing member within the louver construction. [0028] FIG. 11 is a perspective view of a louver having edges provided with grooves which inter-engage with adjacent louvers or shutter rails when the louvers are closed to block light. [0029] FIG. 12 is a cross-sectional view showing two louvers each fabricated, as seen in FIG. 11 , closed in a light-blocking position. [0030] FIG. 13 shows an alternate embodiment of the light-blocking louver of FIG. 11 . [0031] FIG. 14 shows a further alternative example of louver construction that may increase louver rigidity, while saving materials. [0032] FIG. 15 shows yet further alternative examples of lover construction. [0033] Like reference numerals are used to designate like parts in the accompanying drawings. DETAILED DESCRIPTION [0034] The detailed description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present example may be constructed or utilized. The description sets forth the functions of the example and the sequence of steps for constructing and operating the example. However, the same or equivalent functions and sequences may be accomplished by different examples. [0035] FIG. 1 shows a representative shutter assembly which is shown and is generally designated by the numeral 10 . A problem common to both shutters fabricated from polymeric materials, as well as older, wood style shutters, is light infiltration between the pivotal louver frame and the fixed frame in which the louver frame is mounted. Light infiltration generally occurs between the stiles and the louvers and between the louvers as well as around the shutter frame where it meets the wall and between the shutter frame and the shutter panel. [0036] The shutter assembly 10 has an exterior frame 12 which is shown as rectangular having an upper, lower and opposite sides 14 , 16 , 18 and 20 which extend around shutter panel 22 . Shutter panel 22 is hinged to the frame 12 having multiple louvers 25 pivotally mounted at opposite ends to the stiles 28 , 29 . Rails 30 , 32 extend between the stiles 28 , 29 at the top and bottom of the shutter panel 22 . A control rod or tilt bar 34 is provided to manually pivot the louvers 25 to establish a selected position to admit or block light. Although a single louver panel 22 is shown, the frame 12 may enclose two or more panels which are hinged either to the exterior frame 12 or to an adjacent louver panel. A divider rail 80 may be added for astetics, or to improve structural rigidity, especially in tall panels. [0037] FIG. 2 shows light blocking material disposed between the frame and shutter panel. Light may leak around any gap that might be present between the frame and shutter panel. The shutter panel is typically hinged to the frame and there is typically a gap around the interface that can allow unwanted light to seep through. A light blocking material may be disposed into a side wall of the shutter panel, a side wall of the frame, or both in order to block light from seeping through. The light blocking material typically has enough give or pliability to effectively fill into any gaps between the frame and shutter panel when the shutter panel is closed into the frame. The filling of the gaps prevents unwanted light from passing into the room. [0038] The shutter panel typically includes one or more louver apertures into which a plurality of louvers may be disposed. Where the ends of the louvers (not shown) abut a side wall of the shutter panel, light blocking material may be disposed there to fill gaps that would also allow unwanted light from entering the room. [0039] The horizontal edges of the louvers may also form a pathway to admit unwanted light where the louvers at the end, and beginning of a set contact the shutter panel. In this case the top and/or bottom rail of the shutter panel and also the stile of the shutter panel may include a plurality of parallel groves that accept a plurality of mating groves disposed in the corresponding louver, where it would contact the shutter panel. [0040] FIG. 3 shows how light may be blocked from entering gaps between the shutter frame 12 and wall 105 . Rather than try to make a frame 12 an exact match to an opening, or to provide a separate gasket to seal out light, a light blocking seal 103 may be provided as an integral part of the frame 12 . The frame 12 may be an extruded with the light blocking seal 103 being co-extruded. Or alternatively the seal may be an added piece. When the frame is inserted into a window opening in the wall 105 , the frame does not need to be an exact fit to block unwanted light. The seal conforms to irregularities in the opening as it is flexible, and unwanted light is blocked from entering the room from any gaps that might otherwise be present between the wall and shutter frame. [0041] FIG. 4 shows how light may be blocked from entering gaps that may be present between louvers and an aperture in the shutter panel in which the louvers are disposed. Where the louvers 25 are disposed in the shutter panel 22 light may enter between gaps between various surfaces of the louvers that are adjacent to the stiles 28 , 29 and rails 30 , and/or divider rail ( 80 of FIG. 1 ) that for an aperture for the plurality of louvers to be disposed into. On faces of the stiles 28 , 29 that abut the louvers a light blocking material 101 may be disposed in a gap formed there between to block unwanted light. Where the louvers 25 are adjacent to a rail 30 , or divider rail ( 80 of FIG. 1 ) one or more grooves may be provided in the rail 30 to accept a mating ridge in the louver. One or more sets of ridges and grooves may be provided to block unwanted light. Accordingly by utilizing the specially constructed louvers and rails (or divider rails) in conjunction with light blocking material disposed about the perimeter of the aperture in the shutter panel light infiltration may be greatly reduced, or eliminated. [0042] FIG. 5 is a partial perspective view of a representative section of the exterior frame, ( 18 , 20 , 16 , 14 of FIG. 1 ), with a section of a representative frame member 18 being shown. Each of the frame members and shutter members is preferably fabricated by extrusion from a suitable synthetic material such as a polymeric material such as polyvinyl chloride, polyethylene, polystyrene, polypropylene being representative. [0043] Each of the frame members are generally L-shaped having a facing 40 , and a rearwardly depending leg 42 which is generally perpendicular to the facing 40 and may be relieved at 41 to reduce material requirements. The facing 40 abuts the wall W and the leg 42 is positioned in a recess R such as the space formed around a window. The recess R is often not dimensionally uniform and may be irregular. Shutter frames are often pre-manufactured based on the nominal dimensions of the recess and they may require extensive cutting and fitting at installation. Cutting and trimming requires time on the part of the installer, increasing costs to the consumer. [0044] To provide for efficiency of installation and also to block light that may infiltrate around the frame, the outer frame or sections of the frame 18 are provided with a co-extruded seal 50 which is a flap of flexible material which will engage the recess wall, providing a clearance space to facilitate installation and squaring of the frame within the recess. [0045] In alternative examples a light blocking seal 60 can be provided or attached to the surfaces “S” of the frame 12 along members 14 , 16 , 18 and 20 . The seal 60 , may be a flexible flap projecting from the edge of the frame. The seal is fabricated from a flexible polymeric material and co-extruded with a component of the assembly such as the louver panel frame section 18 , making the seal an integral component which can be efficiently fabricated in the same process as the shutter components. [0046] FIG. 6 is a cross-sectional view of a section of an exterior shutter frame as seen in FIG. 5 provided with another embodiment of the co-extruded light-blocking seal 60 . Louver panel 22 is shown as hinged at H to the frame section 18 and, when closed, the seal 60 will block infiltration of light from the window recess R around the frame 12 . Flap 50 will also assist in blocking light. The co-extruded light-blocking seal 60 is shown as circular and the seal may take other configurations such as oval or semi-spherical. [0047] FIG. 7 shows a tight screw assembly for securing and adding structural integrity to a louver panel 22 , particularly a louver panel having increased height. Typically a louver panel such as louver panel 22 , which exceeds five feet in height, typically requires a divider such as a fixed bar member extending between the vertical stiles ( 28 , 29 of FIG. 1 ), generally positioned at an intermediate location to align with the window frame. FIG. 1 shows a representative shutter assembly having a divider rail 80 . However, such a divider rail 80 can distract from the overall aesthetics of the louver panel. Accordingly, the support provided by the fixed divider rail 80 can be eliminated by incorporating tight louver screw assemblies at selected locations between the stile's and louvers 25 to provide the necessary structural integrity. [0048] Blind bores 80 are provided in the outer edges of opposite stiles 28 , 29 adjacent the ends of a louver 25 at a selected location. The blind bores 80 each receives a fastener 82 shown as an elongate, screw having a head 84 , such as a flathead, and a threaded body section 85 . The screws extend through bores 86 in the opposite stiles and the end of the screws engage the ends of the adjacent louver 25 end. Bearings 88 , which are thrust bearings, are interposed between the bottom of the blind bores 81 and the heads 84 of the screws. Low friction flat washers 89 of nylon or other suitable material are interposed on opposite sides of the thrust bearing 88 . The screws are then tightened into engagement with the louver 25 so that the screws and louver 25 turn together. The bearings 88 allow the screws to turn with the louver as an integral unit. Thus, the louver screw secured to the stiles and to the louver in this way provides additional structural integrity between the stiles, often eliminating the need for a divider rail and also reduce the tendency of the screws to “strip” out of the louver end. [0049] FIG. 8 is a detail view of a shutter stile and an adjacent louver broken away showing the installation of a tension-control pins placed between the stile and louver at selected locations to frictionally secure the louvers to prevent the tilt rod from causing the louvers to pivot. Another problem with conventional shutters is that over a prolonged period of use, wear and tear will occur between the louver pivot pin and stile so the weight of the tilt rod will cause unintended movement of the louver causing the louvers to pivot to a closed position from a selected open or partially open position. With the present structure, this problem is alleviated by the use of pivot pins 90 . As seen in FIG. 5 , the pivot pins 90 extend between the vertical stiles 28 , 29 and the adjacent louver 25 at pivot locations. [0050] The pivot pins 90 have an elongated cylindrical body 92 having a point 93 at one end and a head 94 at the opposite end. The body 92 has a section 95 of increased diameter immediately adjacent the had which is a bearing surface. A portion of the body 92 may be provided with axially extending ribs or splines 96 to increase frictional engagement with the louver 25 . [0051] A sleeve 98 extends about the bearing surface of section 95 and is retained by the head 94 . The inner end of the sleeve carries a flange 99 . The head and the sleeve of the tension pins are inserted in a blind bore in the stiles 28 , 29 at selected locations. The flange 98 will abut the vertical, inner edge of the adjacent stile. The body of the pins 90 are inserted into an aligned bore 102 in the end of the louver in a tight fit and further secured by the splines 96 . The louver 25 and pin body rotate supported by the fixed bearing sleeve 98 , reducing the tendency of the pivot pin from “stripping” out of the louver. [0052] FIG. 9 shows examples of a light-blocking material 101 according to the present invention in which light-blocking seal 101 is disposed along an edge of a shutter component, such as along the inner edges of stiles 18 , 20 , and rails 14 , 16 , or to the edges of the frame as previously described herein. The light-blocking material 101 may take several forms in the materials utilized and in its construction. [0053] A light seal 70 b is disposed into to the edge of a shutter component such as adjacent to (such as being disposed into a grove 76 b ) the inner edges of stiles 18 , 20 , and rails 14 , 16 , or to the edges of the frame or other component in which light is to be blocked. The light-blocking seal 70 b , rather than being co-extruded, is slidably disposed into a channel 76 b , and in alternative examples may be or bonded or adhesively secured to hold it in place, to its associated shutter component. As shown, the light-blocking seal is generally made of a siliconized pile material 72 d or its equivalent, and is generally curved, or round in shape, with a substantially tangent point on the outer circumference of the pile surface 72 c bonded to a flexible strip 72 b . Securing the pile 72 d to the backing strip 72 b in this way provides relief for the protruding ledges of the channel 76 b so that the light blocking seal 70 b may be easily slid into the channel 76 b . The strip 70 b is inserted into a typically T-shaped grove or channel 76 b disposed into the stile 18 The backing strip 72 b may be made of any suitable material that is rigid, flexible and also easily bonded glued or otherwise attached to the pile material 72 d . The pile material may be a siliconized pile, a felt or pile material which may be natural fibers such as cotton or wool or synthetic fibers such as polyamide. The pile material 72 d is provided in a suitable color such as black or white, depending on the light blocking preference of the user. The seal 70 b , for example, will block much of the light infiltration between the stile and, louver edges. [0054] The alternative light-blocking material 70 , rather than being co-extruded, is adhesively secured or bonded to its associated shutter component. The light-blocking seal is generally T-shaped having a base 72 and an upwardly projecting leg 74 . The base and leg are formed from a suitable material such as a felt or pile material which may be natural, fibers such as cotton or wool or synthetic fibers such as polyamide. The seal 70 is provided in a suitable color such as black or white, depending on the light blocking preference of the user. Preferably the edges of the stiles and, rails to which the seal 70 is attached are slightly undercut or routed at 75 to accommodate insertion and adhesive securement of the base portion 72 of the light-blocking seal. The seal 70 , for example, will block much of the light infiltration between the stile and louver edges. [0055] FIG. 10 shows a representative louver component 25 with internal support 1002 which may be manufactured by a co-extrusion process. In shutters having adjustable louvers, the louvers are supported for pivoting on opposite stiles by pivot pins disposed in an aperture 1003 . The assembly and fabrication of this type of shutter involves the steps of fabricating the components and completing the frame structure in which the louver panels are to be installed. Shutters made of polymeric materials have a distinct advantages in terms of durability, reduced warpage, ease of fabrication, although even these materials may sag particularly after a long period of installation in windows where the louvers are subject to high temperatures. [0056] As mentioned above, the louvers 25 are preferably fabricated by extrusion from a suitable polymeric material. In order to provide additional strength and resistance to sagging and loss of structural integrity, the extruded louvers are provided with an embedded stiffening section 110 . The embedded stiffening section 110 is shown as a generally inverted V-shaped metal section, preferably aluminum, which can be incorporated at the time of extrusion and to provide the desired additional strength. The section is perforated at multiple locations 112 along its length for weight reduction and for increased adhesion within the louver. [0057] FIG. 11 is a perspective view of louvers 25 having edges provided with grooves 120 , 122 which inter-engage with adjacent louvers or shutter rails when the louvers are closed to block light. Another source of light infiltration occurs between adjacent louver edges when the louvers are closed as louvers with out edges simply rest against each other. Louver 25 may be provided with light-blocking features 120 , 122 formed along the opposite edges 124 , 126 of the louver 25 . Any number of groves may be provided to form a meandering channel to block light infiltration. Also as shown each set of grooves and ridges disposed at opposite ends of the louver 124 , 124 are disposed on opposite sides of the louver 25 so that when the louvers are closed each lover engages with its neighbor. [0058] FIG. 12 shows a pair of louvers 25 in a closed, light-blocking position from the end. The light-blocking features each comprise a pair of parallel spaced-apart grooves 130 forwardly facing along one edge 124 of the louver, separated by a projection 135 . The terms “forwardly facing” denote an orientation toward the room when the louvers are closed. The opposite louver edge 126 is also provided with a pair of parallel grooves 132 . The grooves 130 , 132 are sized and positioned so that the grooves 130 along the edge 124 of a louver inter-engage with the grooves 132 along the edge 126 of the next adjacent louver when the louvers are closed as shown here. [0059] The upper louver rail and the lower louver rail are provided with compatible configurations to engage the upper edge of the upper most louver and the bottom edge of the lower most louver in the louver panel. [0060] Although, for most efficient light-blocking, the louver edges with multiple grooves, may work well, since grooves in the shutter louver edges are an efficient light-blocking configuration, other inter-engaging configurations may also be utilized. A single groove along each louver edge may be sufficient for some installations. [0061] FIG. 13 is a cross-sectional view showing two alternatively constructed louvers 225 each, closed in a light-blocking position. The edges 142 , 144 of the adjacent louvers 225 are routed forming opposite facing shoulders 150 , 152 which inter-engage and abut when the louvers are closed to provide light-blocking. The louvers are symmetrical in construction so that when assembled the tab 152 of one louver, fits into a recess 144 of the adjacent louver. [0062] FIG. 14 shows a further alternative example of louver construction that may increase louver rigidity, while saving materials the louver 25 shown may be formed from any convenient material. As seen from the end 1402 the structure has cavities to save materials and reduce weight. At the center 1404 where extra rigidity may be of use extra support provided by internal members or braces formed into the material is provided. Also show is an insert 1406 that may be added if it is determined that additional strength is needed, by sliding it 1408 into a corresponding cavity. In the louver shown provision for an end mounted tilt rod is provided by an aperture 1410 disposed at an edge of the louver 25 . [0063] FIG. 15 shows yet further alternative examples of louver construction. As can be seen in the figure alternative louver configurations 1501 , 1502 are possible that incorporate many of the features described herein. [0064] It will be obvious to those skilled in the art to make various changes, alterations and modifications to the invention described herein. To the extent such changes, alterations and modifications do not depart from the spirit and scope of the appended claims, they are intended to be encompassed therein. [0065] Those skilled in the art will realize that the process sequences described above may be equivalently performed in any order to achieve a desired result. Also, sub-processes may typically be omitted as desired without taking away from the overall functionality of the processes described above.

A window shutter assembly having flexible light blocking seals molded in the frame or on the edges of the stop surface of the frame. The invention also includes fasteners for securing the louver frame of shutters and also for applying tension to the louvers to resist undesired louver tilt due to wear and the effects of gravity. Additional light blocking features include T-shaped strips of a fibrous material which is secured to a suitable location such as in a groove along the side of the louver panel stile and louvers having edges which inter-engage in the closed position to efficiently block light.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND [0001] 1. Field of the Disclosure [0002] Embodiments disclosed herein relate generally to apparatuses and methods for providing a seal during drilling operations. Specifically, embodiments disclosed herein relate to a sealing device that is configured to seal around a drill string. [0003] 2. Background Art [0004] An earth-boring drill bit is typically mounted on the lower end of a drill string and is rotated by rotating the drill string at the surface or by actuation of downhole motors, turbines, or both. During operations, the drill string may be translated through the wellbore created by the drill bit. Further, during operation, high pressure fluid within the wellbore may need to be prevented from being released. As such, a seal may be provided that is capable of sealing the wellbore during drilling operations. [0005] Generally, a rotating control device (“RCD”) that seals around a drill string is used to seal the wellbore during operations. As shown in FIG. 1 , the RCD 30 includes a stripping element 31 disposed within an annulus 32 of the RCD 30 . During operation, the annulus 32 of the RCD 30 is in fluid communication with the wellbore. As such, the pressure within the wellbore may be exerted upon the stripping element 31 of the RCD 30 . An example of a rotating control device may be found in U.S. patent application Ser. No. 11/556,938 filed on Nov. 6, 2006 and entitled Rotating Control Device Apparatus and Method, hereby incorporated by reference herein in its entirety. [0006] Further, during operation, the drill string may be translated through the RCD 30 and into the wellbore. Typically, the drill string includes a plurality of drill pipes connected by threaded connections located on both ends of the plurality of drill pipes. As such, threaded connections may be flush with the remainder of the drill string outer diameter or may be “upset,” having an outer diameter larger than the remainder of the drill string. As the drill string is translated through the wellbore and the RCD 30 , the stripping element 31 may squeeze against an outer surface of at least one of the plurality of drill pipes, thereby sealing the wellbore. Typically, the stripping element 31 is made up of an elastic material that may mechanically deform to seal around various diameters of drill pipe. However, over time the stripping element 31 may become worn and unable to substantially deform to provide a seal around the drill string. Consequently, the stripping element 31 must be replaced, which may lead to down time during drilling operations that can be costly to a drilling operator. [0007] Accordingly, there exists a need for methods and apparatuses for improving the sealing of a wellbore during stripping operations. SUMMARY OF THE DISCLOSURE [0008] In one aspect, embodiments of the present disclosure relate to an adjustable sealing device including a housing configured to be engaged within an annulus of a rotating control device, at least one sealing element disposed within the housing, and a variable pressure control device configured to energize a fluid disposed within the housing to maintain a seal between the sealing element and a drill string. [0009] In another aspect, embodiments of the present disclosure relate to a rotating control device including an adjustable sealing device installed in an annulus between a drill string and a wellbore, the adjustable sealing device including a housing, at least one sealing element disposed within the housing, a variable pressure control device configure to energize a fluid disposed within the housing to maintain a seal between the sealing element and the drill string. [0010] In yet another aspect, embodiments of the present disclosure relate to a method of sealing a wellbore, the method including providing an adjustable sealing device to a rotating control device, positioning at least one sealing element of the adjustable sealing device between the wellbore and a drill string, tripping the drill string through the wellbore, sensing changes in a diameter of the drill string as it is tripped, and regulating a fluid pressure to maintain a seal between the at least one sealing element and the drill string when the drill string is tripped through the at east one sealing element. [0011] Other aspects and advantages of the invention will be apparent from the following description and the appended claims. BRIEF DESCRIPTION OF DRAWINGS [0012] FIG. 1 shows a rotating control device in accordance with the prior art. [0013] FIG. 2 shows a cross-section of a sealing device in accordance with embodiments of the present disclosure. [0014] FIG. 3 shows a cross section of a sealing device in accordance with embodiments of the present disclosure. [0015] FIG. 4 shows a cross section of a sealing device in accordance with embodiments of the present disclosure. [0016] FIG. 5 shows a cross section of a sealing device in accordance with embodiments of the present disclosure. DETAILED DESCRIPTION [0017] In one aspect, embodiments disclosed herein relate to apparatuses and methods to provide a seal during drilling operations. Specifically, embodiments disclosed herein relate to a sealing device that is configured to seal around a drill string. During operation, the sealing device is configured to maintain a seal with the drill string as the drill string is translated through the wellbore. Additionally, the sealing device may be configured to control a pressure of a fluid, thereby allowing the sealing device to seal around various shapes and sizes of components of the drill string. [0018] Referring now to FIG. 2 , an adjustable sealing device 200 in accordance with embodiments of the present disclosure is shown. As shown, the adjustable sealing device 200 includes a housing 210 , a sealing element 220 , a fluid (e.g., hydraulic fluid) 230 , and a pressure control device (i.e., a pressurized fluid source) 240 . In one embodiment, the adjustable sealing device 200 may be in fluid communication with a wellbore (not shown) and configured to maintain a seal around a drill string 10 while the drill string 10 is translated through the wellbore and the adjustable sealing device 200 . [0019] Housing 210 may be configured to allow a drill string 10 to be translated through the adjustable sealing device 200 . In one embodiment, the housing 210 may include an annulus 212 that allows the drill string 10 to extend and be translated through the adjustable sealing device 200 . During operation, the annulus 212 of the housing 210 may be configured to be in fluid communication with the wellbore. As such, a pressure of the wellbore may be exerted on the sealing element 220 of the adjustable sealing device 200 . [0020] Further, the housing 210 may be configured receive the fluid 230 and the sealing element 220 . In one embodiment, the housing 210 includes a chamber 214 that is configured to receive the fluid 230 and at least a portion of the sealing element 220 . Moreover, the housing 210 may include an aperture 216 that allows the chamber 214 to be in fluid communication with at least one pressure control device 240 . [0021] Furthermore, in certain embodiments, the housing 210 may include at least two sections that allow the sealing element 220 to be removably disposed within the chamber 214 of the housing 210 . For example, the housing 210 may include upper and lower sections (not shown) coupled together through bolts, threads, or other attachments known in the art. Accordingly, the upper section may be disconnected from the lower section to allow sealing element 220 to be inserted or removed from chamber 214 of housing 210 . [0022] Additionally, in select embodiments, the housing 210 may include at least one connection (not shown) that is configured to couple the adjustable sealing device 200 to the wellbore. The at least one connection may include bolts, threads, bearings, or any other attachment method known in the art. In one embodiment, the at least one connection may be configured to removably connect the adjustable sealing device within an RCD coupled to the wellbore. [0023] In selected embodiments, sealing element 220 may be at least partially disposed within chamber 214 of housing 210 and configured to seal around drill string 10 , which may result in sealing the wellbore that is in fluid communication with adjustable sealing device 200 . For example, sealing element 220 may deform against an outer surface 12 of the drill string 10 extending through the adjustable sealing device 200 , thereby not allowing pressure within the well bore to be released through the adjustable sealing device 200 . As such, the sealing element 220 may include rubber, metal, or any other deformable materials that allow sealing element 220 to form a seal around the drill string 10 . Further, in selected embodiments, sealing element 220 may comprise a single piece of material, whereas in other embodiments, sealing element 220 may include multiple pieces of material coupled together to form a seal around drill string 10 . [0024] In certain embodiments, the sealing element 220 may include a circular shape, a rectangular shape, an irregular shape, or any other shape able to seal around drill string 10 . In further embodiments, the sealing element 220 may include chamfers 222 disposed proximate an inner surface 224 of sealing element 220 . One skilled in the art will appreciate that chamfers 222 may allow various shapes and diameters of the drill string to more effortlessly pass through sealing element 220 , while still maintaining the seal between the sealing element and outer surface 12 of the drill string 10 . [0025] Hydraulic fluid 230 may be disposed within in chamber 214 of housing 210 and configured to exert a pressure upon sealing element 220 to maintain the seal between it and the drill string 10 . For example, in one embodiment, fluid 230 may be pumped into the chamber 214 of the housing 210 through an aperture 216 that is in fluid communication with the fluid line 242 of the pressure control device 240 . As the fluid 230 is pumped into the chamber 214 , a pressure of the fluid 230 within the chamber 214 may increase, which may cause the sealing element 220 to deform against the outer surface 12 of the drill string 10 . In another embodiment, the fluid 230 may be released from the chamber 214 to allow the pressure of the fluid 230 within the chamber 214 to be decreased. One skilled in the art will appreciate that decreasing the pressure of the fluid 230 within the chamber 214 may allow a portion of the drill string 14 having a diameter greater (i.e., an upset portion) than the remainder of drill string 16 to pass through adjustable sealing device 200 , while maintaining the seal around drillstring 10 . In selected embodiments, fluid 230 may include hydraulic fluid, water, drilling mud, air, or any other fluid capable of applying pressure on sealing element 220 . [0026] The pressure control device 240 may be in fluid communication with the chamber 214 of the housing 210 . As shown, in one embodiment, the pressure control device 240 may be in connected to the housing 210 through the flow line 242 . Further, the pressure control device 240 may be configured to control the pressure of the fluid 230 within the chamber 214 of the housing 210 . For example, the pressure control device 240 may pump fluid 230 into the chamber 214 of the housing 210 through the fluid line 242 , thereby increasing the pressure of the fluid 230 within the chamber 214 . In addition, the pressure control device 240 may allow fluid 230 to be released from the chamber 214 of the housing 210 through fluid line 242 . One skilled in the art will appreciate that the pressure control device 240 may include a pump, a motor, a valve or any other components known in the art to control the pressure of the fluid 230 . [0027] Referring now to FIG. 3 , in select embodiments, adjustable sealing device 200 may include at least one ring 250 to transfer the pressure of fluid 230 to sealing element 220 . For example, in one embodiment, as the pressure of fluid 230 within chamber 214 is increased, ring 250 may be configured to be translated in the U direction and exert a force on sealing element 230 . Additionally, in another embodiment, as the pressure of the fluid 230 within the chamber 214 is decreased, ring 250 may be configured to be translated in the D direction, which may decrease the force exerted on sealing element 220 . Ring 250 may comprise a metallic material or any other material capable (i.e., a rigid material) of transferring the pressure of the fluid 230 to the sealing element 220 . One skilled in the art will appreciate that ring 250 may be configured to seal the fluid 230 within the chamber 214 of the adjustable sealing device 200 . Furthermore, one skilled in the art will appreciate that the ring 250 may uniformly transfer the pressure of the fluid 230 to the sealing element 220 . [0028] In certain embodiments, the adjustable sealing device 200 may include sensors 260 , 262 that configured to sense a diameter of the drill sting 10 , as shown in FIG. 3 . In one embodiment, the adjustable sealing device 200 may include an upper sensor 260 disposed above the sealing element 220 on the housing 210 of the adjustable sealing device 200 . Accordingly, the upper sensor 260 may be configured to sense a diameter of the drillstring 10 above the sealing element 220 . In another embodiment, the adjustable sealing device 200 may include a lower sensor 262 disposed below the sealing element 220 on the housing 210 of the adjustable sealing device 200 . As such, the lower sensor 262 may be configured to sense a diameter of the drillstring 10 below the sealing element 220 . [0029] In select embodiments, the sensors 260 , 262 may be electrically connected to the pressure control device 240 and configured to send a signal to the pressure control device 240 . The signal may then be used by the pressure control device 240 to regulate the pressure of fluid 230 within the chamber 214 of the housing 210 . One skilled in the art will appreciate that the sensors 260 , 262 may include a trip switch, a limit switch, or any other sensor capable of sensing a diameter of the drill string 10 . As such, as a large diameter portion (e.g., a threaded connection or “tool joint”) is about to pass through adjustable sealing device 200 from below, lower sensor 262 may detect the increased diameter and instruct pressure control 240 to lower pressure of fluid 230 in chamber 214 to ease the passage of the tool joint. Once through, upper sensor 260 may instruct pressure control 240 to increase pressure of fluid 230 in chamber 214 to a level that is optimized for the remainder of the drill string. [0030] Referring now to FIGS. 2 and 3 , during operation, the adjustable sealing device 200 is positioned to be in fluid communication with the wellbore. Further, during operation, the drillstring 10 may be translated through the adjustable sealing device 200 into or out of the wellbore. In one embodiment, as the drill string 10 is translated through the adjustable sealing device 200 , the pressure of the fluid 230 within the chamber 214 of the housing 210 may be increased or decreased to maintain the seal between the sealing element 220 and the outer surface 12 of the drill string 10 . This may be accomplished by pumping fluid 230 into and/or releasing fluid 230 out of the chamber 214 of the housing 210 using the pressure control device 240 . In another embodiment, at least one of the sensors 260 , 262 may detect the diameter of the drill string 10 before the drill string 10 is translated through the adjustable sealing device 200 . The at least one sensor 260 , 262 may then send a signal to the pressure control device 240 that may be used by the pressure control device 240 to control the pressure of the fluid 230 within the chamber 214 , thereby allowing the adjustable sealing device 200 to seal around various shapes and diameters of the drill string 10 . [0031] Referring now to FIG. 4 , an adjustable sealing device 300 in accordance with embodiments of the present disclosure is shown. The adjustable sealing device 300 includes a housing 310 , a fluid 330 , and a pressure control device 340 similar to the adjustable sealing device 200 shown in FIG. 2 . However, the adjustable sealing device 300 includes a plurality of sealing elements 320 that are configured maintain a seal around the outer surface 12 of the drillstring 10 . One skilled in the art will appreciate that the plurality of sealing elements 320 may increase the reliability of the adjustable sealing device 300 by providing multiple seals along the outer surface 12 of the drill string 10 . [0032] In certain embodiments, a housing 410 of an adjustable sealing device 400 may have various geometries that allow a fluid 430 from a pressure control device 440 to be disposed on various surfaces of a sealing element 420 , as shown in FIG. 5 . One skilled in the will appreciate that the various geometries of the housing 420 and disposition of the fluid 430 does not depart from the present disclosure. [0033] Embodiments disclosed herein may provide for one or more of the following advantages. In particular, embodiments of the present disclosure enable an adjustable sealing device (e.g., 200 , 300 , 400 ) to be used in conjunction with an RCD to prevent premature wear of the stripping element (e.g., 31 ). If, during a drilling operation using an RCD, the drill string is to be retrieved, the stripping element may be removed and replaced with an adjustable sealing device in accordance with embodiments disclosed herein. As such, the adjustable sealing device (e.g., 200 , 300 , or 400 ) would be capable of adjusting the pressure of fluid ( 230 , 330 , or 440 ) when upset threaded connection joints are passing therethrough so that sealing elements ( 220 , 320 , or 420 ) are not damaged. Once the trip in or trip out operation is completed, the adjustable sealing device may be retrieved and the stripping element reinstalled. [0034] While the present disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as described herein. Accordingly, the scope of the disclosure should be limited only by the attached claims.

An adjustable sealing device including a housing configured to be engaged within an annulus of a rotating control device, at least one sealing element disposed within the housing, and a variable pressure control device configured to energize a fluid disposed within the housing to maintain a seal between the sealing element and a drill string is disclosed. A method of sealing a wellbore, the method including providing an adjustable sealing device to a rotating control device, positioning at least one sealing element of the adjustable sealing device between the wellbore and a drill string, tripping the drill string through the wellbore, sensing changes in a diameter of the drill string as it is tripped, and regulating a fluid pressure to maintain a seal between the at least one sealing element and the drill string when the drill string is tripped through the at least one sealing element is also disclosed.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD [0001] The present disclosure relates generally to swing type garage doors and in particular the present disclosure relates to loading and use of swing type garage doors BACKGROUND [0002] Garage doors of the swing-type are typically comprised of a door that remains in a single panel configuration even when the door is being opened and is open. Such doors are often opened and closed using hydraulic cylinders. These swing-type doors are typically of either unitary construction, or are manufactured in sections that must be assembled when the door sections are delivered to an installation site, requiring additional time and effort to assemble the door. [0003] Further, swing type doors may have a truss permanently attached to a bottom of the door that provides added stability against drooping of the door when it is open. These built-on trusses require additional materials, and are permanent, so they can be obstacles in front of a door, as well as potential tripping points. Further doors with permanent trusses either require shipping a more unwieldy portion of door, or additional assembly time and effort when the door sections arrive at the installation location. [0004] Wind loading on doors in high wind conditions can be very high. Such wind loading can lead to bowing or even buckling of doors. Some bracing systems for doors employ additional cross bracing within the door body frame, but even additional bracing cannot prevent damage in higher winds. [0005] For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for improvements in swing type door bracing, trussing, and load distribution. SUMMARY [0006] In one embodiment, a swing type garage door includes a door body rotationally connected to a door frame, the door body rotatable between a first closed position and a second open position. The door body includes a trussing system with vertical truss members and horizontal truss members, the horizontal members having openings through which the vertical members extend, the openings having sides on either side of the vertical truss member, to distribute a load on the door body to the door frame in both a vertical and a horizontal direction. [0007] In another embodiment, a swing type garage door includes a door body rotationally connected to a door frame, the door body rotatable between a first closed position and a second open position. The door body includes a first section and a second section hingedly connected with a hinge, the door body foldable from a first operating configuration in which the first and the second sections are pinned so that they form a substantially rigid door body, and a second transport configuration for storage and transport in which the first and second sections are folded about the hinge to reduce the effective dimensions of the door body. [0008] In still another embodiment, a swing type garage door includes a door body rotationally connected to a door frame, the door body rotatable between a first closed position and a second open position. The door body has a main door body section and a door load truss section, the door load truss section hingedly connected at a bottom of the main door body and rotatable between a first configuration in which the main door body section and the door load truss section are substantially coplanar and a second configuration in which the door load truss section is substantially perpendicular to the main door body section. [0009] In another embodiment, a swing type garage door includes a door body rotationally connected to a door frame, the door body rotatable between a first closed position and a second open position. The door body has at least one brace rotatably connected to the door body on an interior thereof, the at least one brace rotatably movable between a first bracing position in which the brace is positioned substantially perpendicular to a plane of the door body and a second storage position in which the brace is substantially coplanar and parallel to the door body. [0010] Other embodiments are described and claimed. BRIEF DESCRIPTION OF DRAWINGS [0011] FIG. 1 is an isometric view of a garage door according to one embodiment of the present invention; [0012] FIG. 1A is a more detailed view of a portion of the garage door of FIG. 1 ; [0013] FIG. 2 is an isometric view of a garage door according to another embodiment of the present invention; [0014] FIG. 3 is an isometric view of a garage door having a door load truss according to another embodiment of the present invention; [0015] FIG. 3A is a view of the garage door of FIG. 3 with the door load truss in another position; [0016] FIG. 3B is a view of the garage door of FIG. 3A with the door shown in an open position; [0017] FIG. 4 is an isometric view of a garage door having door braces according to another embodiment of the present invention; and [0018] FIG. 4A is a view of the garage door of FIG. 4 with the door braces in a folded position. DETAILED DESCRIPTION [0019] In the following detailed description of the embodiments, reference is made to the accompanying drawings that form a part hereof. In the drawings, like numerals describe substantially similar components throughout the several views. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be utilized and structural, logical, and electrical changes may be made without departing from the scope of the present invention. [0020] The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present disclosure is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled. [0021] Referring to FIG. 1 , a one piece swing type garage door 100 has vertical 102 and horizontal 104 trussing that intersects in a number of locations over the span of the door 100 . The vertical trussing pieces 102 and horizontal trussing pieces 104 serve to distribute a load on the door from the trussing to the external frame 106 of the door, which is typically stronger than the door itself. Typical doors may have both horizontal and vertical trussing, or one or the other. However, for door 100 , the horizontal and vertical trussing are interconnected to distribute load in both the horizontal and the vertical directions. [0022] To accomplish this, the horizontal and vertical trussing is constructed as shown in greater detail in FIG. 1A . Individual vertical truss member 152 and individual horizontal truss member 154 are shown at an intersection 156 thereof. Horizontal truss member 154 has an opening 158 through which vertical truss member 152 extends. Horizontal truss member 154 has opening 158 configured in size in one embodiment to fit a width 160 of vertical truss member 152 . Sides 162 and 164 of horizontal truss member 154 are on either side of the vertical truss member 152 . Because of this, when assembled, the truss members 152 and 154 provide a distributed load from stress from either side of the door. In one embodiment, the vertical truss members 152 and vertical truss members 154 are joined at the intersection 1566 , for example by bolting, welding, epoxying, or the like. [0023] The interconnection of the vertical and horizontal truss members spreads a load on the door 100 over the entire frame. Loads, such as from lifting of the door 100 and wind loading, are dispersed both horizontally and vertically, as opposed to traditional loads being dispersed only vertically. [0024] Door hydraulics 108 are connected between the frame 106 and the door body 110 so as to open the door 100 by moving the door body 110 in response to the door hydraulics 108 . Hydraulics 108 are hinged so as to rotate about their mounting points at the door frame 106 and at the door body 110 . When hydraulics 108 are actuated, using a hydraulic motor or hydraulic controller (not shown), a hydraulic cylinder of the hydraulics 108 extends and opens the door. The door body 110 is hingedly connected to door frame 106 along its top 112 , and rotates on a rotational axis 114 between open and closed positions. [0025] If there is an increased wind load or expected extra wind load on a door such as door 100 , the depth of the horizontal trusses is increased in one embodiment. In contrast, typical doors would increase the number of vertical trusses or make them much larger in size and thickness, adding extra weight. The increase in the depth of the horizontal trusses, that is their depth in a direction substantially perpendicular to the face of the door 100 , which adds some weight, but not much, for the resulting increase in handling a wind load. [0026] FIG. 2 shows a door 200 according to another embodiment of the present invention. Door 200 has a hinge 202 extending horizontally across the door, hingedly connecting top section 204 and bottom section 206 of the door 200 . The hinge 202 allows the door 200 to be shipped in a folded orientation, while still having the sections 204 and 206 connected to each other. This makes the door 200 easier to ship, and also requires less installation time than a typical door, since a typical door is shipped in sections that must be assembled on site. The hinge 202 extends in this embodiment horizontally along the door 200 . In shipping, the door 200 is folded along hinge 202 . To prepare the door 200 for installation, the door is unfolded, and pins 208 are used to pin the top and bottom sections 204 and 206 together quickly and reliably. [0027] In yet another embodiment, a door 300 is shown in FIGS. 3 , 3 A, and 3 B. Door 300 has a hinge 302 hingedly connecting a top section 306 and a door load truss section 304 . In normal operation of the door 300 when it is closed ( FIG. 3 ), the sections 304 and 306 are co-planar and locked in that position with pins 308 , so that the door 300 functions as any other door. However, when the door 300 is opened (FIG. 3 B), the door load truss section 304 is rotated about hinge 302 to a position in which it is substantially perpendicular to the section 306 , forming a door load truss that assists in prevention of sagging of the door 300 , due to its weight and/or size, during opening and while the door 300 is open. In this embodiment, then, the door load truss 304 is only used as a load truss when the door 300 is open. In contrast, normal door load trusses are permanently affixed in a position where they are substantially perpendicular to the face of the door. These normal door load trusses require additional materials, and present potential obstacles when working around the door. The folding truss allows a cleaner profile for the door when it is down, but still provides the horizontal stability of a permanent truss when the door is opened or is in the open position. [0028] As shown in FIG. 3A , the hinged operation of the door load truss section 304 does not interfere with the closing of the door 300 , and the door load truss section 304 can be maintained in its load bearing position in which it is substantially perpendicular to door face 301 of section 306 . In this configuration, the door load truss section 304 also provides windage loading support for the door 300 . [0029] In still another embodiment, shown in FIGS. 4 and 4A , door 400 has at least one (two are shown, although more or fewer are within the scope of the disclosure) added brace 402 . Brace 402 is in one embodiment movable on hinges 404 between a first position in which brace 402 is substantially perpendicular to door face 401 and a second folded-in position in which brace 402 is substantially parallel and adjacent to door face 401 (see FIG. 4A ). Brace 402 has a first vertical member 406 and a second vertical member 408 substantially parallel to first vertical member 406 . Vertical members 406 and 408 are separated by horizontal members 410 . When the brace 402 is in its first position, it can in one embodiment be pinned or otherwise secured to a floor 420 to provide additional wind loading for the door 400 . If pinned, brace 402 has a pin 412 that may be placed through a hole or opening 414 in brace 402 and which extends into a hole 422 in the floor 420 or the like. In its first position, brace 402 provides additional structural support for the door 400 , and the ability to secure the brace to floor 420 provides further structural stability especially in high wind situations. When two braces 402 are used and are in their first positions, the door frame is loaded in three sections. [0030] Door braces are attached to the main door section 412 for added wind loading and stiffening when the door 400 is down. For high wind situations, such as for a hurricane or the like, the normally folded door braces 402 are extended to be substantially perpendicular to the door. When additional wind loading is required, the braces are unfolded to approximately a 90 degree angle to the door, adding additional stability and loading. The braces can then be pinned to the floor or the like. Also, the positioning of the braces breaks the loading down into approximately three equal pieces of the main door. Alternatively, the braces 402 can be permanently or semi-permanently pinned in their first open positions if desired. [0031] One of more of the embodiments and variations described above can be integrated with a door of the type described. The hinged door load truss 304 of FIG. 3 can be used on other types of doors as well. [0032] Combinations are within scope of the disclosure, for example a door can have the hinged sections of FIG. 2 combined with the horizontal and vertical integrated trussing of FIG. 1 . Such combinations will be understood by those of skill in the art to be within the scope of the disclosure. Conclusion [0033] A swing-type garage door has been described that includes in various embodiments one or more of: hinged sections for ease of transfer and installation; integrated horizontal and vertical trussing to distribute wind loading; a door load truss that is integral with the door and only folds perpendicular for opening and open doors; and door braces pinnable to a floor for additional structural stability in storms and the like. [0034] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.

A swing type garage door has one or more of several features, including a door body rotationally connected to a door frame, the door body having one or more of: a trussing system having vertical and horizontal truss members, the horizontal members having openings through which the vertical members extend to distribute a load on the door body to the door frame in both a vertical and a horizontal direction; first and second sections hingedly connected with a hinge to allow ease in transport; a main door body section and a door load truss section hingedly connected at a bottom of the main door body to provide load trussing when the door is open; and at least one brace rotatably connected to the door body on an interior thereof and rotatable between a first bracing position and a second storage position to brace in high wind loading conditions.

You are an expert at summarizing long articles. Proceed to summarize the following text: This is a continuation in part of application Ser. No. 08/792,597, filed Jan. 31, 1997 U.S. Pat. No. 5,836,135. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wall assembly which includes a drainage track of the type primarily intended for use in combination with exterior insulation and finish systems (generally referred to in the construction industry as EIFS), the construction of which provides for positive drainage of moisture which may collect between a structure's exterior surface or coating and its weather-resistant barrier. 2. Description of the Prior Art In today's construction industry, numerous residential structures, and even a significant number of commercial structures such as, for example, apartment buildings, have their exterior surfaces finished with a stucco-type coating applied over a foam insulation board. One such board is, for example, that disclosed in U.S. Pat. No. 4,572,865, and other such boards are well known in the prior art and in the construction industry. Such exterior finishes are generically referred to as Exterior Insulation and Finish Systems, and will be referred to hereinafter as EIFS. While such EIFS constructions have proved to be quite satisfactory for their relative ease of installation, their insulating properties, and their ability to receive a variety of aesthetically-pleasing finishes, a serious and vexing problem associated with EIFS construction exists. This problem is one of water accumulation behind the exterior wall covering. Such water may be the result of condensation, but is frequently the result of wind-driven water that may enter behind the exterior wall covering at any point where the exterior surface of the coating is penetrated. Such water accumulation may be the result of poor workmanship or design, deterioration of flashing or sealants over time, lesser quality doors or windows, or any other penetration or compromise of the exterior finish. When such water penetration or condensation occurs, absent effective, reliable means for draining the water from behind the EIFS exterior construction, structural damage to the building may occur. The construction industry has certainly recognized such problems associated with water penetration behind EIFS exteriors, and other insulated building components such as, for example, windows. For example, U.S. Pat. No. 4,569,872 describes an insulating window panel which includes a bottom frame member for draining condensation. According to the disclosure of that patent, a transparent plastic sheet having a number of vertical channels formed therethrough is disposed in face-to-face relationship with a polyethylene closed cell foam sheet. The purpose of the vertical channels is to permit water to flow downwardly, and the lower frame member is dimensioned and configured to provide a drain opening along the bottom thereof. This drain opening is provided by insuring that the composite panel is mounted in spaced apart relation to the bottom of the frame member. U.S. Pat. No. 2,264,961 discloses a thermal insulation structure having vertical channels formed on one face thereof to provide a ventilating space for the circulation of air to dry out water which may penetrate the insulating material. However, this patent does not disclose or suggest any means for positively draining water from inside the wall. According to the disclosure of U.S. Pat. No. 4,570,398, concrete may be sprayed onto the exterior of rigid sheet insulation and wire to form a continuous waterproof outer surface. However, one may reasonably question such a statement, for concrete is typically permeable to water. Finally, U.S. Pat. No. 5,511,346 discloses a rigid, thermoplastic foam board useful in below-grade residential and commercial insulating and drainage applications. According to the disclosure of this patent, the board includes a plurality of vertical channels formed therein to provide for water drainage and to protect a below-grade-building wall from excessive moisture. Without in any way questioning the asserted utility of the devices and structures identified above, any practical study of these devices reveals significant shortcomings. Virtually none of the prior art devices actually provide means for positively draining water away from the building structure. While a drain opening is provided in the panel disclosed by U.S. Pat. No. 4,569,872, establishing that drain opening clearly requires care and precision in fitting the lower frame member to the composite panel. While the other devices discussed above provide means for "ventilating" insulating panels, none provide for water drainage from behind the panels. It is, therefore, clear that there remains a great need in the art of building constructions utilizing EIFS exteriors so as to provide for the drainage of penetrating water or condensing moisture from behind the insulation so as to prevent water-related structural damage to the building. Such a device must not only provide for positive water drainage, but also must be of economical manufacture and of relatively simple use and installation so as not to adversely affect building costs. SUMMARY OF THE INVENTION The exterior wall assembly of this invention comprises an outer weather-resistant layer, or coating, a heat insulating panel, situated interiorly to the outer layer, a wall (sheathing) situated interiorily to the insulating panel, and a drainage track, the drainage track being attached at the bottom of and projecting outwardly from the wall, the outward projection of the drainage track supporting the insulating panel and having one or more apertures for removal of water from the wall assembly. This assembly provides for the dispersal of water from the region between the insulating panel and the wall or sheathing, which may, for example, be an OSB board or fiberboard. The drainage track of the exterior wall assembly is of the type primarily intended for use in combination with exterior insulation and finish systems (EIFS). The principal purpose of the drainage track is to provide positive means for draining water from behind the insulating material so as to prevent water-related structural damage to the building. The drainage track comprises a flashing leg by which the track is attached to the exterior wall or sheathing of the building along the bottom edge of that sheathing. A major portion of the flashing leg overlaps the sheathing, and a minor portion of the flashing leg extends below the sheathing's bottom edge. Extending outwardly in angular relation (e.g., perpendicularly) from the bottom edge of the flashing leg is a first structural web. In a preferred embodiment, a second structural web is joined to the first web and extends upwardly in angular relation thereto and advantageously is substantially parallel to the flashing leg. A horizontal leg is joined to the second web and extends in angular relation thereto, outwardly from the flashing leg. Thus, in cross-section, the drainage track defines a substantially L-shaped configuration with a drain channel defined by the lower portion of the flashing leg, the first structural web, and the second structural web. The horizontal leg defines a support surface for placement of an insulating panel thereon. The channel formed between the flashing leg and the horizontal leg has one opening (e.g., a slot) or more than one opening for drainage. A plurality of drain apertures are advantageously formed in the channel to provide for positive drainage of water therefrom. The exterior wall assembly of the invention includes means for surfacing the insulating panel. The means comprises a weather-resistant layer on the outwardly facing surface of the insulation panel. This layer may be preformed on the insulating panel before final construction of the exterior wall assembly or applied during such construction. The weather-resistant layer is attached to the outwardly projecting horizontal leg of the drainage track. This attachment may be accomplished in various ways, such as by cementing together the two. Advantageously, the cement extends around and exteriorily to the lower portion of the insulating panel and continues uninterruptedly onto the bottom surface of the horizontal leg. In a further embodiment of the invention, the drainage track, which is preferably plastic, may be variously constructed for attachment, or cementation, to the weather-resistant layer. The horizontal leg can include a variety of means which provide a keyway or holding action to facilitate the attachment. The horizontal leg may be variously shaped for this purpose. A number of projections may extend downwardly from its bottom surface, such as triangles, arrows, rectangles, other ridges, etc. In a preferred embodiment, a plurality of finish apertures are formed through the horizontal leg so as to bring about proper adhesion of the building's exterior weather-resistant layer, or coating, to the lower portion of the wall assembly. In another embodiment, the horizontal leg can also incorporate a combination of shaped projections and apertures for proper adhesion. Advantageously, the exterior layer is a stucco-type exterior finish, which finish is applied to the exterior surface of the insulating panel according to known procedures and techniques. In a preferred embodiment, the drainage track is formed from extruded polyvinyl chloride (PVC). However, the scope of the invention is not to be limited to the use of this material. Any suitable material such as, for example, other plastics or metals, may be used for forming the drainage track. In similar fashion, the cross-sectional configuration described above is nothing more than a preferred embodiment, and alternative configurations will be presented hereinafter. The invention accordingly comprises an exterior wall assembly possessing the features, properties, and the relation of elements which will be exemplified in the article hereinafter described, and the scope of the invention will be indicated in the claims. BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which: FIG. 1 is a perspective view, partially in section to show interior detail, of an EIFS wall construction showing use and installation of the drainage track of this invention according to a preferred embodiment. FIG. 2 is a sectional view of the installation shown in FIG. 1. FIG. 3 is a perspective view of a segment of the drainage track used in the installation of FIG. 1. FIG. 4 is a bottom, plan view of the drainage track of FIG. 3. FIG. 5 is a front elevation of the drainage track of FIG. 3. FIG. 6 is a side sectional view of the drainage track of FIG. 3. Similar reference characters refer to similar parts throughout the several views of the drawings. DETAILED DESCRIPTION Referring first to the views of FIGS. 1 and 2, one sees a perspective and a sectional view of a portion of a standard building construction, the exterior of which is finished with an exterior insulation and finish system (EIFS), generally indicated as 10. The drainage track of this invention is generally indicated as 12. The building segment shown in FIGS. 1 and 2 comprises a slab, or foundation, 14 having a sole plate 16 attached thereto. Using studs (not shown), the exterior of the building is initially formed by sheets of sheathing 18. The EIFS 10, in combination with the drainage track 12 of this invention, is actually attached to sheathing 18. As seen in the view of FIG. 1, drainage track 12 is attached to sheathing 18 as by staples 20, or any such suitable fastening means such as, for example, nails, brads, or screws. Next, a weather resistant barrier 22 is applied over sheathing 18 such that the lower portion of barrier 22 overlaps flashing leg 24 of drainage track 12. Spacers 26 are next applied over barrier 22, and the bottom portion of spacers 26 also overlaps flashing leg 24. Insulating material 28 is next applied. The bottom portion of insulating material 28 also overlaps flashing leg 24. Referring to the view of FIG. 2, it can be seen that the bottom edge 30 of insulating material 28 actually rests on horizontal leg 32 of drainage track 12. The view of FIG. 1 further illustrates that the exterior of insulating material 28 is provided with a reinforcing mesh 34. Finally, the finish coat 36 is applied over the exterior of insulating material 28 and its mesh 34 to complete the installation. Referring to the view of FIG. 2, it can be seen that finish coat 36 actually "wraps around" the bottom edge 30 of insulating material 28 and onto the bottom surface of horizontal leg 32. Having thus described elements of a standard EIFS installation except for drainage track 12, attention is invited to the fact that the subject matter of this invention is directed to a wall assembly including an exterior insulation and finish system and drainage track 12. That is to say, drainage track 12 is useful in combination with virtually any EIFS 10, and the individual elements of such an exterior finish may certainly vary from job to job. For purposes of example only, weather-resistant barrier 22 is typically a type 15 felt, or an equivalent. Spacers 26 may be 11/4"×31/2" closed-cell polyethylene sill sealers, 1/2" diameter closed-cell backer rods, or their equivalents. Virtually any commerciallyavailable insulating board may be used as the insulating material 28, and the board described in U.S. Pat. No. 4,572,865 is preferred. The insulating panel is beneficially formed from a polyisocyanurate or polyurethane foam. The finish coat 36 may be any coating/sealant as specified for application to and compatibility with insulating material 28. Sheathing 18 may be plywood, gypsum, cement board, fiberboard, OSB board, or other equivalents therefor. It is to be understood that local conditions and building codes will, at least to some extent, dictate the individual components of EIFS 10. Having thus described a typical EIFS 10 used in combination with drainage track 12 of this invention, attention is now invited to the views of FIGS. 3-6 for a more detailed description of a preferred construction for drainage track 12. As previously indicated, drainage track 12 is preferably extruded from PVC. However, drainage track 12 may be formed from any suitable, substantially rigid material such as, for example, other plastics, other synthetics, or metal. As perhaps best seen in the views of FIGS. 3 and 6, drainage track 12 comprises a flashing leg 24 having a top edge 38 and a bottom edge 40. A first structural web 42 is joined to bottom edge 40 and extends in angular relation thereto. In this preferred embodiment, first structural web 42 is substantially normal to flashing leg 24. A second structural web 44 extends from first web 42 in angular relation to first web 42. Again, as shown in this preferred embodiment, second structural web 44 is substantially normal to first structural web 42 and extends upwardly in the direction of top edge 38 such that second structural web 44 is substantially parallel to flashing leg 24. Horizontal leg 32 is joined to the top of second web 44 and extends in angular relation to second web 44, terminating in a distal edge 46. A plurality of drain apertures 48 are formed in spaced apart relation through first structural web 42. In a preferred embodiment, a plurality of finish apertures 50 are formed in spaced apart relation through horizontal leg 32. Referring to the sectional view of FIG. 6 and the sectional installation view of FIG. 2, it can be seen that a portion of flashing leg 24 adjacent bottom edge 40, first structural web 42, and second structural web 44 effectively define a drain channel for positively draining any water that penetrates the EIFS 10 or that condenses therebehind. Referring to the view of FIG. 2, the top of this drain channel is actually defined by bottom edge 30 of insulating material 28, inasmuch as that bottom edge 30 rests on horizontal leg 32. In the preferred embodiment, drain apertures 48 are about 3/16" in diameter, and finish apertures 50 are about 1/8" in diameter. This size for drain apertures 48 ensures that water will pass therethrough and not be retained in the drain channel as by surface tension, while is of a sufficiently small size to prevent the entry of pests. The smaller size and greater number of finish apertures 50 provide for effective bonding of the finish coat 36 to horizontal leg 32. Though not shown in the drawings, it may be desirable to form the bottom surface of horizontal leg 32 with a plurality of ridges, or with a combination of a plurality of apertures 50 and ridges to further enhance the bonding between horizontal leg 32 and finish coat 36. It should also be noted that the distance between flashing leg 24 and second web 44 plus the distance defined between second web 44 and distal edge 46 are less than the thickness of the EIFS 10 used in combination with drainage track 12. Thus, a variety of EIFS 10 constructions may be used in combination with a single drainage track 12 so long as the exterior of the insulating material 28 extends beyond distal edge 46. As indicated above, this construction for drainage track 12, as heretofore described and as shown in the drawing figures, is but a preferred embodiment. First structural web 42 need not necessarily be normal to the plane defined by flashing leg 24, and second structural web 44 need not necessarily be normal to the plane defined by first structural web 42. For example, first web 42 and second web 44 could define a V-shaped drain channel, rather than the substantially rectangular channel shown in the sectional view of FIG. 6. The scope of this invention is intended to encompass such a construction, and drain apertures 48 might then be said to be formed through both the first structural web and the second structural web. In similar fashion, the shapes of first web 42 and second web 44 might be altered to define a curved, substantially U-shaped drain channel with drain apertures formed through the bottom of the U. In all instances, however, flashing leg 24 is attached to the building such that the entire EIFS 10 overlaps top edge 38 of flashing leg 24 so that water will necessarily be directed toward the drain apertures 48. Similarly, horizontal leg 32 will always be spaced apart from flashing leg 24 and define a top, planar surface suitable for operatively receiving bottom edge 30 of the insulating material 28. A key advantage of the drainage track of this invention is that the outer portion of its drainage channel, e.g., structural web 44 of the embodiment shown in the drawings, serves as a block to prevent clogging of the drain apertures. If the drainage track were to simply be an L-shaped device, without an upwardly projecting and blocking member such as web 44, the installer, in applying the coating and reinforcing mesh over the lower edge of the construction, would tend to plug the drainage holes with the coating because there would be no guide limiting how far back his trowel could go. Thus, the track would become ineffective. Structural web 44 or any equivalent step portion therefore plays a key role by serving as a "guide" in limiting how far back the plasterer pushes his trowel with the coating. This guide prevents him from going all the way back to the substrate (slab 14) and filling the vent holes with coating. It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and, since certain changes may be made in the above assembly without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. Now that the invention has been described,

An exterior wall assembly comprising an outer weather-resistant layer, a heat insulating panel situated interiorly to the outer layer, a wall situated interiorly to the insulating panel, and a drainage track. The drainage track includes a clog-resistant drainage channel so that water collecting behind the insulating panel may drain from the assembly. The drainage track, in a preferred form, is extruded from PVC and defines a substantially L-shaped configuration in cross-section. An elongated, relatively tall flashing leg is provided for attachment of the drainage track to the wall such that all water-resistant material and insulation laps over the flashing leg to direct water into the drainage channel. Finish apertures are provided through a portion of the drainage track so that exterior finish such as, for example, stucco, will readily adhere and bond to the drainage track.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION In the building industry it has been the common practice for many years to construct foundations, interior and exterior wall structures of concrete blocks arranged in rows and held together by mortar. Also, in many related building environments it is conventional to use a bonding medium, such as mortar, to hold together elements of structure, such as concrete blocks. In most cases, it is a time consuming process to manually apply the mortar or similar bonding agent to each row of concrete blocks or similar work surface by means of a trowel or similar hand implement. The conventional procedure is to scoop the mortar onto the working surface and then spread the mortar by hand using a hand implement. In addition to the time required this procedure is also wasteful. Mortar is lost as unequal amounts are applied indiscriminately and spread along the surface of the concrete blocks. This is often aggrivated by the worker's haste in manually applying the mortar in order to complete the job as soon as possible. Thus, the need for a device to butter building structures such as concrete block in a more efficient and economical way with mortar or similar bonding material. A device which eliminates the problem of mortar waste and provides a quick and efficient manner of applying mortar to the concrete block arrangement or other building surface is certainly a desirable improvement. Naturally the automatic application device should be of low cost and easily manufactured, assembled and used. It should be usable in a quick and efficient manner to automatically apply mortar in controlled predetermined amounts to a chosen location on a work surface. SUMMARY OF THE INVENTION With the above background in mind, it is among the primary objectives of the present invention to provide a hand-size applicator designed to be quickly and efficiently aligned with a work surface, such as a row of concrete blocks, and moved along that surface on a guided path to automatically meter out predetermined amounts of mortar or similar building material to predetermined locations on the work surface. In this manner, the mortar or similar material is quickly and efficiently applied automatically in the desired amount. Thereafter, concrete blocks or similar building structures can be applied in a continuation of the building process. The applicator is designed so that it can be quickly and efficiently indexed on a row of blocks forming a work surface for application of material such as mortar. Thereafter, the application is moved smoothly along the row of blocks and automatically a predetermined amount of mortar or similar material is metered from the applicator onto the surface of the blocks. Mortar waste is eliminated since the next row of blocks can be immediately applied to the surface containing the mortar to continue the building process. There is no need for removal of excess mortar or redistribution of mortar on the surface. The applicator of the present device employs a mortar dividing blade to distribute and direct mortar through discharge openings in the applicator as it is moved along the work surface. In one embodiment there are two discharge openings spaced on the trailing edge to provide for two uniform rows of motar continuously discharged from the applicator. The device is designed so that a suitable beater is employed to assist in discharging the mortar from the applicator in a desired manner as the applicator is moved along the work surface. It is also an objective to provide a unitary applicator structure including a housing having an access opening for introduction of a desired supply amount of building material to an interior chamber. A divider directs the mortar toward two discharge openings in the trailing end of the applicator at spaced points across the transverse surface of the blocks along which the applicator is moved in a longitudinal direction. A suitable handle is provided on the applicator for assisting in handling the device in use. The applicator is designed with suitable runner wheels to assist in longitudinal movement of the applicator along the work surface. Furthermore, the applicator is provided with guide wheels to capture a block therebetween and provide for indexing and alignment of the applicator on the block surface so that the metered mortar or like building material is applied at the desired location on the block arrangement. Another form of the applicator employs a housing with side walls converging toward one another from top to bottom to provide a funnel shaped enclosure for a chamber to hold the building material. The side walls direct the material toward one or more openings adjacent the bottom of the housing. A beater arrangement is utilized which employs an axle bent into a configuration to form one or more paddles within the housing in alignment with the openings therein to facilitate direction of building material through the openings. The beater axle is driven by an arrangement of gears which in turn is driven by a roller extending downward from the housing to engage a surface adjacent to the building surface and rotate as the applicator is moved along the building surface. Rotation of the roller rotates the axle through the gear arrangement and the paddle configuration of the axle directs the building materials through the openings onto the building surface. It is a further objective to provide an applicator which is of unitary construction, is formed of inexpensive material and can be used quickly and efficiently for the automatic distribution of desired amounts of building material such as mortar to a building surface such as an arrangement of concrete blocks. It is designed and formed of inexpensive material and is lightweight for ease of handling in use. In summary, an applicator for introducing and spreading building material in a controlled manner to a building surface is provided. The applicator includes a housing adapted to contain a predetermined amount of building material therein. Guide means is on the housing adapted to engage with the building surface and direct the applicator into desired alignment therewith and along a predetermined path when the applicator is associated with a building surface and moved there along. Metering means is in communication with the interior of the housing and with at least one opening to the exterior thereof to direct a predetermined pattern of building material from the interior of the housing through the opening and onto the building surface. With the above objectives among others in mind, reference is made to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: FIG. 1 is a perspective view of the applicator of the invention; FIG. 2 is a side elevation view of the applicator applying mortar to a building structure formed of concrete blocks; FIG. 3 is a top plan view of the applicator of the invention; FIG. 4 is a sectional end view thereof taken along the plane of line 4--4 of FIG. 3; FIG. 5 is a bottom plan view of the applicator of the invention; FIG. 6 is a side elevation view of an alternative embodiment of the applicator applying mortar to a building structure formed of concrete blocks; FIG. 7 is a top plan view of the alternative embodiment of the applicator of the invention; and FIG. 8 is a partially sectional end elevation view of the alternate embodiment of the applicator of the invention. DETAILED DESCRIPTION Applicator 20 is formed with a housing 22. The housing includes a vertical leading end wall 24 with a pair of opposing longitudinal side walls 26 and 28 and a trailing wall 30. Trailing wall 30 has a lower mouth portion 32 to form an opening 34 and an upper tapered portion 36. The interconnected walls forms a substantially rectangular shaped housing 22. A top wall 38 extends partially over the upper surface of housing 22. The remainder of the upper surface is formed with an opening 40 providing an entrance to an interior chamber 42. The inner surface of tapered portion 36 of the trailing wall, the inner surface of opposing sides 26 and 28 and a tapered intermediate wall 44 of the housing form the walls for chamber 42. The portion of housing 22 between tapered intermediate wall 44 and leading end wall 24 is sealed by a bottom wall 46. The bottom of chamber 42 is formed by a V-shaped divider blade 48. The apex 50 of the divider blade 48 extends upward into chamber 42 and in a longitudinal direction. It terminates at the inner surface of tapered portion 36 of trailing wall 30 at one end and at tapered intermediate wall 44 in the other direction. It is mounted in conventional fashion such as by welding or can be formed unitary with the interconnected portion of the housing. The divider blade 48 has its two sides 52 and 54 extending downwardly and outwardly away from apex 50 to terminate in longitudinal flanges 56 and 58 respectively. Flanges 56 and 58 are spaced from side walls 28 and 26 respectively thereby providing channels 60 and 62 therebetween respectively. These channels 60 and 62 are opened at opening 34 of mouth 32 at the trailing end of the housing. This provides a pair of spaced communicating passages between the interior chamber 42 and the exterior of the housing. A handle 64 is mounted on the upper surface 38 of housing 22 and extends upwardly therefrom to facilitate gripping and handling of applicator 20. A pair of L-shaped side brackets 66 and 68 respectively are affixed to side walls 26 and 28 respectively. The L-shaped brackets extend longitudinally along the side walls and have one leg 70 affixed to the side wall in a conventional manner such as by welding, riveting, bolting or any other well known manner. The other leg 72 of each L-shaped bracket extends at right angles to the leg 70 and outward in a tranverse direction with respect to applicator 20 and longitudinally along the side walls. The leading edge 74 of each L-shaped bracket extends beyond leading wall 24 in the direction of travel and the trailing edge 76 is located adjacent to opening 34 of mouth portion 32 of the trailing wall 30. The brackets 66 and 68 do not extend beyond mouth 32 in the trailing direction. A pair of spaced vertical axles 78 and 80 are mounted to transverse horizontal leg 72 of each bracket in a conventional manner such as by threading a nut 82 on a threaded end of the axle extending through an appropriate aperture in leg 72. A guide wheel 82 is mounted on the end of axle 78 distal from leg 72 and similarly a second guide wheel 84 is mounted at the end of the axle 80 distal from leg 72. As shown, these wheels lie in a horizontal plane for rotation about the vertical axles 70 and 80. Each of the L-shaped brackets 66 and 68 contains aligned pairs of wheels 82 and 84 which form a guide means for applying the applicator 20 to a work surface. A suitable wheel shield 86 can be mounted in a conventional manner on each of the four shafts to protect the wheels 82 and 84 from damaging blows and from other contaminating substances which could affect operation of the wheels. The number of pairs of wheels and positioning thereof is a matter of choice with two sets of wheels shown in the depicted embodiment. The leading set of wheels are mounted to brackets 66 and 68 on the portion thereof extending forward of leading wall 24. The trailing pair of wheels 82 are mounted in an intermediate position in alignment with a portion of chamber 42. On each leg 70 of L-shaped brackets 66 and 68 is a horizontal axes 88 extending transversely with respect to the applicator 20 and in alignment with axle 80. Each axle 88 is mounted to leg 70 by means of a conventional fastener such as a threaded nut 90 or other well known means in a similar manner as discussed in connection with axles 78. Inside of leg 70 rotationally mounted on each axle 66 is a runner wheel 92. The pair of runner wheels 92 on the brackets 66 and 68 are aligned with one another and extend downward beyond the bottom edge of housing 22 for engagement with the work surface. A similar pair of axle and wheel assemblies are spaced from wheels 92 in the rearward direction. Each axle 94 is mounted in the same manner by use of an appropriate threaded nut 96 and a runner wheel 98 is rotationally mounted thereon. The pair of wheels 98 are located in the depicted embodiment just forward of the tapered intermediate wall 44 forming the leading wall of chamber 42. Runner wheels 98 similar to runner wheels 92 extend below the bottom edge of housing 22 for engagement with the work surface. A beater assembly 100 is mounted adjacent to trailing wall 30. One end portion 102 is rotatably mounted to side wall 26 and leg 70 of bracket 68. The other end portion 104 is rotatably mounted to the opposing side wall 28 and leg 70 of L-shaped bracket 68. The end portions 102 and 104 are interconnected with a locking shaft 106 which in turn has a beater wheel 108 mounted thereon for rotation therewith. The interlocked shaft portions 102, 104, locking shaft 106 and wheel 108 are designed for interconnected rotation. Formed on shaft portion 102 between side wall 26 and locking shaft 106 is a paddle 110. The paddle is in alignment with channel 62 exiting at mouth opening 34. A similar paddle 112 is formed in end portion 104 between side wall 28 and locking shaft 106. Paddle 112 is in alignment with channel 60 exiting at opening 34 of mouth 32. These paddles 110 and 112 can be formed in any conventional manner. In the embodiment shown, they are formed by bending shaft portions 102 and 104. As the beater assembly 100 rotates, the paddles or beaters 110 and 112 will periodically engage with building material contained within chamber 42 and assist in directing it outward through channel 60 and 62. Wheel 108 is large enough to extend downward beyond the bottom edge of housing 22 so that it engages with the building surface and rotates as the applicator is moved along the building surface thereby facilitating beating of the building material by rotating paddles 110 and 112 as the material is metered from the applicator. In use, applicator 20 is filled with a building material, for example, mortar through opening 40 in its upper end to fill or partially fill chamber 42. The applicator is then grasped in a convenient manner such as by grasping handle 64 and placed onto the building surface for application of the mortar. In the depicted embodiment, a building surface formed of an arrangement of stacked rows of concrete blocks 112 is being utilized. The interstices between the blocks 112 are filled with mortar 114 to bond and hold the blocks together and form a structure such as a foundation or wall. The upper exposed surface of the last formed row of blocks provides the working surface 116 for application of the mortar 114 from applicator 20. The applicator is designed so that each pair of guide rollers 82 and 84 are spaced slightly wider than the width of the row of blocks 112. Suitable adjustment means can be provided to accommodate a variety of width blocks. By preadjustment, the applicator is quickly indexed on the blocks by placing the applicator down with the blocks positioned between the guide wheels 82 and 84 as shown in FIG. 2. The applicator is fully seated so that runner wheels 92 and 98 engage with the work surface 116 along with beater wheel 108. Handle 64 is then grasped along with any other desired portion of the applicator and the applicator is moved along surface 116 in the direction of the arrow of FIG. 2. As this movement occurs mortar 114, directed by the divider blade 48 will move into channels 60 and 62. Thereafter encouraged by periodic contact from beater paddles 110 and 112, the mortar 114 will by uniformly distibuted in a pair of spaced strips along work surface 16 as it exits from channels 60 and 62 during longitudinal movement of applicator 20. In this manner, mortar is automatically applied in a uniform manner in desired amounts along the work surface as the applicator is moved. At the end of the surface 116 which is the end of the upper row of blocks 112 the applicator can be easily lifted from the work surface and a row of blocks placed on work surface 116 where mortar distributed through channels 60 and 62 will bind the next row or blocks in position. A constant amount of mortar is provided in this manner through the work surface in the desired amount and distribution. Thus, there is no waste of mortar or need for further use of tools or implements to redistribute mortar or remove or add mortar. The job can proceed more efficiently with labor and material savings resulting therefrom. Thus, the applicator 20 of the present invention provides a device for buttering concrete block by applying mortar in a more efficient and economical way. Mortar waste material occurring with manual application is eliminated. Applicator 20 can be formed of any inexpensive conventional material such as a metal or plastic, for example 1/8 inch sheet aluminum. Corrosion or rust resistant material is desirable. The structure can be formed of a welded construction with closed seams, smooth and polished. The various wheels can be conventional metal or plastic. It has been found effective to form the wheel of the beater assembly of rubber material. The applicator is lightweight and thus easy to handle and manipulate during use adding to its efficiency. An alternative embodiment of applicator 20a is depicted in FIGS. 6-8. In most respects it operates the same and is structured the same as applicator 20. Modifications are present in respect to the chamber for housing the building material and the beater means for metering the building material from the chamber onto the building surface. Similar parts bear similar numbers with the addition of the subscript a. Chamber 118 for containing building material 114 in the housing 22a is formed with a pair of opposing end walls 120 and 122 and a pair of opposing side walls 124 and 126. The side walls and end walls are interconnected and converge toward one another from top to bottom. The side walls and end walls form the enclosure for chamber 118 and have a wide opening 128 at the top for insertion of building material. There are two spaced openings 130 and 132 at the bottom for exit of building material 114 from the applicator onto the building surface. Thus the end walls 120 and 122 and the side walls 124 and 126 serve to form a funnel shaped structure for facilitating direction of the building material toward openings 130 and 132 to promote application of the building material. A modified metering mechanism in the form of a beater assembly 134 is also employed. Beater assembly 134 includes an axle 136 extending across the housing and rotationally mounted at one end to side wall 124 and rotatably extending through an opening in side 126 on the other side of the housing. Axle 136 is bent as it extends across the housing at a number of points to form a series of paddles 138. These paddles form beaters which engage the building material 114 and facilitate its direction through openings 124 and 126 and onto the building surface. The end of beater axle 136 extending through side wall 126 has a beveled gear 140 mounted thereon to rotate therewith. Adjacent to beveled gear 140 and meshed therewith is a second beveled gear 142 rotatably mounted in conventional fashion on the housing. A third beveled gear 144 is positioned perpendicular to bevel gears 140 and 142 and meshes with bevel gear 142. The third bevel gear 144 is mounted on a vertically disposed shaft 146 which is journaled and rotatably mounted on the housing. Shaft 146 extends downward through an opening in L bracket 66a. The opening is large enough so that free rotation of shaft 146 is permitted. The upper end of shaft 146 is fixed in position in a conventional manner to the housing within a protective gear box 148. The bottom end of shaft 146 has an enlarged roller 150 mounted thereon. Roller 150 is an elongated roller and is mounted in fixed position on shaft 146 so that as roller 150 rotates shaft 146 rotates. The size of roller 150 is a matter of choice with a larger size roller naturally providing a greater surface engagement with the side walls of the adjacent concrete block when the applicator 20a is positioned on the building surface. In operation, building material is positioned in chamber 118 and applicator 20a is positioned on the building surface in the same manner as the above discussed applicator. Movement of the applicator along the building surface in the direction of the arrow causes roller 150 to rotate which in turn causes shaft 146 and attached bevel gear 144 to rotate. Bevel gear 144 then rotates bevel gears 142 and 140. Rotation of bevel gear 140 rotates axle 136 and paddles 138 to facilitate direction of building material 114 through openings 130 and 132 onto the building surface. Thus the several aforenoted objects and advantages are most effectively attained. Although several somewhat preferred embodiments have been disclosed and described in detail herein, it should be understood that this invention is in no sense limited thereby and its scope is to be determined by that of the appended claims.

An applicator for introducing and spreading building material in a controlled manner to a building surface. The device includes a housing adapted to contain a predetermined amount of building material therein. Guides are on the housing adapted to engage with the building surface and direct the applicator into desired alignment with the building surface and to direct the applicator along a predetermined path when the applicator is associated with the building surface and moved there along. A metering structure communicates with the interior of the housing and with at least one opening to the exterior thereof to direct a predetermined pattern of building material from the interior of the housing through the opening and onto the building surface. The applicator is particularly useful in applying and spreading mortar to bind an arrangement of rows of concrete blocks.

You are an expert at summarizing long articles. Proceed to summarize the following text: This is a divisional of copending application Ser. No. 07/340,861 filed on Apr. 20, 1989, now U.S. Pat. No. 5,013,176. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connector for tubular truss assemblies. More specifically, the invention relates to a connector which forms a part of a truss cell wherein tubing interconnected between selected adjacent connectors is loosely held in the connector to facilitate shaping the truss assembly to desired contours and for distributing the forces and mechanical stresses existing throughout the assembly, to each member thereof. 2. Description of the Prior Art The formation of truss assemblies using connectors of the prior art generally involves either the welding or bolting rigidly together of the constituent parts of the assemblies. Examples of such assemblies are shown in U.S. Pat. No. 3,596,950, U.S. Pat. No. 4,101,230 and U.S. Pat. No. 4,343,562. With the application of strong transverse forces on the truss assemblies described in the above patents the rigid welds tend to fracture or tear. The truss assemblies in the prior art generally will load the plate elements to which they are welded. Usually this loading is undesirable since it may easily lead to laminar tearing of the plate material. Other connectors in the prior art provide rigid connectors incapable of contouring to form desired geometric shapes such as cylinders and semi-spherical or completely spherical domes. Examples of such connectors are described in U.S. Pat. No. 1,144,491, U.S. Pat. No. 3,563,580 and U.S. Pat. No. 4,076,431. In each case the resulting structure is limited solely to specific geometric shapes such as tetrahedral or fixed sloped roofs for portable car or boat storage. The present invention remedies the deficiencies of the prior art. The connector includes a plurality of receptacles for receiving in a loosely fit fashion tubing which interconnects adjacent connectors. The truss assembly is maintained in a unitary structure by means of either securing the tubing to the respective connector or by means of truss wires connected to selected ones of adjacent connectors and biased to urge the interconnected connectors together. The structural members of the truss are held in position in compression in a loose fit fashion. This unique manner of loose coupling allows slight movement of expansion and contraction and the distribution and defocusing of forces throughout the truss assembly. The loose coupling diminishes the potential of fracture and tearing characterizing the aforementioned connectors of the prior art. Since the forces are distributed throughout the truss assembly, the undesirable concentration of forces and stress is minimized. Because stress concentrations are minimized lighter and weaker structural tubing can be used. Yet another unique feature of the loosely fitting coupling of the truss tubing and connectors is the ability to "turn corners" of the surfaces it forms to create a non-planar assembly either for functional or aesthetic purposes. To form desired structural shapes such as a cylinder it is required to turn the plane of the face of the truss assembly by the slight shortening of the tubing on the inner side of the turn desired to be formed. Spheres, domes, squares, rectangular and composite truss cells such as hexagonal, octagonal and the like are within the contemplation of the present invention. Moreover the loose fitting concept which is contrary to designs of the prior art provide for rapid assembly and disassembly. The truss once quickly assembled is less prone to the damaging effects induced by movement of the assembly because of the "forgiveness" inherent in non-rigid structures. Once assembled, parts of the truss assembly can be removed without collapse of the entire assembly. Thus alterations in design during assembly is possible without substantial breakdown of the entire truss assembly. SUMMARY OF THE INVENTION In accordance with the invention a connector for use in a tubular truss assembly is provided having an essentially planar base portion and a receptacle means which is secured to and extends normally from the base portion. A cover portion includes an aperture for slidable mounting on the receptacle means. A plurality of indentations are disposed along radii of the cover portion. The indentations open downwardly toward the base portion for gripping the tubular truss members between the cover and base portions. Means are provided for urging the cover and base portion together for gripping the tubular truss members therebetween. Preferably the indentations are triangular and the cover portion is slidable on the receptacle for adapting to varying sized tubing. Preferably the base and cover portions include paired apertures for receiving bolt means for urging together the base and cover portions. Preferably the base portion includes indentations similar to and in matching relationship to the indentations of the cover portion. Preferably a tubular truss includes a plurality of connectors and a plurality of tubes coupled to and between adjacent ones of selected connectors. The truss also includes tensioning means coupled between selected adjacent ones of the connectors for urging the connectors together. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a connector according to the invention. FIG. 2A is a front elevation view of the connector of FIG. 1. FIG. 2B is a top view of the connector of FIG. 1. FIG. 3 is a top view of an alternate embodiment of a connector according to the invention. FIG. 4 is a side elevation view of the connector of FIG. 3. FIG. 5 is a top view of still another embodiment of a connector according to the invention. FIG. 6 is a side elevation view of the connector of FIG. 5. FIG. 7 is a perspective view of a portion of a truss assembly incorporating connectors according to the present invention, namely the connectors of FIGS. 5 and 6. FIG. 8 is an elevation view of a portion of a truss assembly incorporating connectors according to the present invention utilizing tension means between selected adjacent ones of the connectors. FIG. 9A is a front elevation partial cutaway perspective view of a truss assembly having unequal tube lengths for forming a spherical or domelike structure. FIG. 9B is a sectional view of the structure of FIG. 9A along lines 9B. FIG. 10A is an exploded perspective view of yet still another embodiment of a connector according to the invention. FIG. 10B is a side elevation view of the connector of FIG. 10A. DETAILED DESCRIPTION OF THE INVENTION The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings. In particular FIGS. 1, 2A and 2B there is shown a first embodiment of the present invention. The connector 1 includes an essentially flat, rigid base portion 2. The base may be formed of a number of structural materials such as, for example, cold rolled steel and the like. The shape of the base portion 2 is essentially planar and as shown in FIG. 1 has a circular outer periphery. As will be described later the shape of the outer periphery may conveniently be in the shape of other geometrical forms such as square or truncated triangular which is usually dependent upon the number of receptacles provided in the connector. Extending normally from the base portion 2 is hollow tubular receptacle 3. The receptacle 3 may be secured to the base 2 by conventional attachment methods such as welding. Spaced apart bolt holes 4 are provided in and extend through the base portion 2. Mounted to the base and on the receptacle 3 is cover portion 5. The cover portion 5 includes a central opening 6A which has a contour similar to but slightly larger than the receptacle 3. This permits the cover portion 5 to slide freely on the receptacle 3 during assembly Spaced about the cover portion 5 and with respect to base portion 2 are downward opening indentations 6. The indentations have side walls 7 and 8 and an apex 9. The apex 9 lies along a radius originating from receptacle axis 10. As shown best in FIG. 1 the indentations 6 are generally triangular in cross-section with the base of the cross-section being proximal and the apex being distal with respect to the base portion 2. The cover portion regions 11 which extend in the region between the indentations 6 are essentially flat and when the cover portion 5 is mounted on the receptacle 3, the regions 11 lie in a plane parallel to the plane of the base portion 2. Disposed about the cover portion 5 are bolt holes 12 which are spaced to be coaxial with corresponding bolt holes 4. In forming a continuous connector assembly, tubing 13 which is to be inserted in and secured by the connector 1, is inserted within the space provided by the indentations 6. Advantageously the triangular cross-section permits use of variable sized tubing since the cover portion will be located in position dependent upon the size of the tube 13. Thus larger sized tubing 13 will cause the cover portion 5 to be spaced further apart from the base portion 2 whereas smaller sized tubing 13 will cause the cover portion 5 to be spaced closer to the cover portion 5. The shape of the indentations therefore provides means for adaptively securing varying sized tubing. Cover portion 5 is urged towards the base portion 2, for maintaining tubes 13 therebetween in locking relationship, by means of bolts 14 which are located through correspondingly aligned holes 4 in the base portion 2 and holes 12 in the cover portion 5 and are secured in place by means of bolt nuts 15. As will be explained in more detail later a tension wire or brace 17 is coupled to the connector 1 as well as to an adjacent connector for urging adjacent connectors together. As shown in FIG. 1 the brace 17 is sandwiched between the base plate 2 and the cover plate 5. However, the brace 17 may also be secured to the connector 1 on the upper surface of the cover plate 5 or to the lower surface of base plate 2. For applications where it is desired to provide a less rigid and more flexible connector, the bolts 14 may be left with a slight slack. Additionally the receptacle 3 may be reduced with respect to the tubing size so that there is provided sufficient space for slight movement of the tube when located in the receptacle. For constructing contoured structures this provision for slight relative motion or loose fit coupling of the tubing within the connector facilitates contouring the structure into other than planar surfaces, such as for example, slight rounded, domed, or cylindrical contours are achievable. An alternate embodiment of the present invention is shown in FIGS. 3 and 4 to which reference is now made. The connector 20 comprises a substantially planar base plate 21 having a tubular receptacle 22 which is normal to the base plate 21 extending along an axis 23. As shown in FIG. 3 the receptacle is circular in cross-section for receiving tubing of circular cross-section having a diameter less than that of the receptacle. It should be noted and as will be described later, the present invention contemplates receptacle and tubular cross-sections in other geometrical shapes other than circular, such as, for example, square or rectangular. Spaced apart along radii R1, R2 and R3 are second receptacles 24. The receptacles 24 lie in the plane parallel to the plane formed by and are attached to base plate 21. Located on the base plate 21 and spaced between adjacent receptacles 24 are holes 25. Securing means such as bolt 26 are mounted through the holes 25 for securing tension truss 27 to the base plate 21. The tension truss 27 serves to urge together adjacent connectors to which it is attached. Although only one tension truss is shown in FIG. 3 it is to be understood that each other of the holes 25 may have a tension truss secured thereto depending upon the nature and construction of the truss assembly. As shown in FIG. 3 tubes 28 are insertable within the receptacle 24 typically through the entire length of the receptacle. A set screw 29 having screw threads matching that machined in the receptacle 24 is advancable downward to engage the tubes 28. Accordingly the receptacles 28 may be, either fixedly or loosely held, within the receptacle depending upon the amount of force exerted by the set screw 29 upon the receptacle. By such arrangement the connector provides the ability for slight movement to accommodate rounded truss structures which may otherwise not be attainable by totally rigid connectors. Referring now to FIGS. 5 and 6 there is shown still another embodiment of the present invention. Essentially planar base plate 30 has mounted thereon normally directed receptacle 31 and planar mounted receptacles 32. Mounting the receptacles 32 to the base plate 30 may be accomplished by any of a number of techniques such as welding. Receptacles 32 are oriented normal to each other and normal to receptacle 31. As shown in FIG. 5 and FIG. 6 the receptacles and tubing inserted therein are square in cross-section. Set screws 34 hold the tubes 33 within the receptacle 32 fixedly or loosely in accordance with the amount of tightening force applied to set screw 34. Disposed on the base plate 30 are through holes 35. Looped through hole 35 is a truss wire 36 crimped so as to maintain the wire coupled to the hole 35. The truss wire 36 serves to urge together adjacent ones of selected connectors in a truss assembly. Although only one wire 36 is shown in FIG. 5 it is to be understood that one or more truss wires, each coupled within respective holes 35 is contemplated dependent upon the location of the respective connector in the truss assembly. Referring now to FIG. 7 there is shown two truss assembly portions 40 of a larger truss assembly (not shown) embodying the inventive concepts heretofore described. Connectors 41 are interconnected by means of tubes 42 in "cell" arrangements comprising five connectors 41A, 41B, 41C, 41D and 41E. Although five connectors are shown it is to be understood that cells comprising four connectors (41E omitted in the configuration shown in FIG. 7) or three connectors or other arrangements are contemplated by the present invention. Tubes 42 are inserted into receptacles of adjacent connectors and secured into place by means of set screws (not shown) previously described. Each cell of five connectors is coupled to adjacent cells to then form an overall structure. Turn buckle TB1 which is coupled between respective connectors 41A and 41B through an interconnecting wire serves to urge connectors 41A and 41B together. In a similar manner TB2 serves to urge connectors 41F and 41G together. In a similar fashion additional turn buckles (not shown) may be inserted in wires between adjacent connectors to urge the respective connectors together. Accordingly each truss cell becomes a self-contained integral unit. The number of cells in either the vertical or horizontal direction with respect to FIG. 7 are added in a manner solely determined by the final structure desired to be assembled. Each cell provides structural enhancement to the overall assembly and loss or damage of one cell as a result of an unforeseen event will not markedly affect the structural integrity of the overall assembly. The cells in the overall assembly support the remaining portion of the assembly by dividing the mechanical stresses existing in the assembly amongst a number of cells and sharing the load from adjacent cells. Referring now to FIG. 8 there is shown an alternative embodiment of a connector "cell" utilizing the connector of FIG. 5. The upper cell 43 includes truss wires 46 arranged in a "square" bracing arrangement with adjacent truss wires 46 coupled together at respective corners 47. A turn buckle TB secured to one of the truss wires 46 when tightened, draws the connectors 45A, 45B, 45C and 45D together. An alternative truss wire connection is shown in the "X" bracing arrangement of cell 44. Truss wires 48 are connected between diagonally opposite connectors 45B and 45F and 45A and 45E respectively. The selections of truss wire arrangements are dependent upon size and load carrying requirements of the truss assembly. In this manner adjacent connectors are drawn together to establish integral connector cells in an overall truss assembly. Referring to FIG. 9A there is shown yet another truss arrangement utilizing the connector of FIG. 3, for an assembly forming a semi-spherical or domelike contour with a cylindrical base. Truss assemblies formed in the manner shown are usable for large structures such as stadiums, air terminals, exhibition halls, as well as for temporary structures such as circus tents where set-up and tear-down times are important considerations, without compromising the strength requirements of the structure. The "cell" geometry of FIG. 9A is square with internal brace wires in a square configuration. It is to be understood that other geometrical shapes such as octagonal are also advantageously used in similar structures. Importantly, truss assemblies of the nature shown do not require the positive air pressure conditions dictated by inflatable pressurized dome structures. For purposes of clarity, except for the peripheral structure, the outer surface of the dome is not shown, but it is to be understood that the dome is formed in a semi-spherical honeycomb or "sandwich" type arrangement. Referring to FIG. 9A and FIG. 9B, connectors 50A, 50B, 50C and 50D form a cell 54 having a square shape. The connectors 50 are urged towards each other by truss wires 51 arranged in a square arrangement with adjacent individual truss wires 51 coupled together at respective corners 52. Four additional truss wires 51 couple corners 52 to respective connectors 50. Also coupled to adjacent connectors are respective tubes 53 which complete each square shaped cell structure. The truss wires 51 may be secured together and to the connectors 50A, 50B, 50C and 50D by any one of a number of conventional techniques. Urging the connectors together may be accomplished by the use of turn buckles interposed in the truss wires 51 or other conventional tightening devices known in the art. The contour shaping of adjacent cells is best illustrated by reference to the cylindrical wall edge portion of the dome structure shown in FIG. 9A. More specifically, connectors 55 and 57 are included in a truss cell that is upstanding and forms a part of the inner surface of the base of the semi-spherical dome. The remaining two connectors of the cell lie in line with respective ones of the connectors 55 and 57 and therefore are not shown. Similarly, connectors 56 and 58 are included in a truss cell that is upstanding and forms a part of the outer surface of the base of the semi-spherical dome. The remaining connectors which are in line with respective ones of connectors 56 and 58 are therefore not shown. Corresponding facing cells forming an inner and outer portion of the dome are spaced apart a distance determined by equal length tubes 61. The curvature of adjacent cells is established by having the interior tubing 62 of a shorter length than exterior tubing 63. In this manner wedge-shaped combinations of spaced apart cells are formed. The general shape of the wedges are determined by the difference in interior and exterior tube lengths. Obviously the greater the difference in interior and exterior tube lengths, the more pronounced the wedge shape. In a similar fashion the cells which are coupled above the first row of cells of the dome have the interior tubing of a shorter length than the exterior tubes, which results in the curving inward of the cell combinations forming thereby a dome-like structure. For structures desired to be cylindrical rather than spherical, then the interior tube lengths would be less than the exterior tube lengths, but side tube lengths of the individual cells would be of equal length. In this manner the cell combinations would form a circumference of the cylinder but would not turn inward as in the case of the dome structure. As mentioned previously the tubing is of similar but smaller cross-section with respect to corresponding connector receptacle cross-sections. By virtue of the smaller cross-section not only is ease of assembly realized, but jamming of the tubing and the connectors is avoided and the contouring of cells and cell combinations is facilitated. Additionally the angle between adjacent receptacles when made unequal provides additional flexibility to form structures other than planar, cylindrical or spherical. Referring now to FIGS. 10A and 10B there is shown yet another alternate embodiment of the present invention. The connector 64 comprises two symmetrical cover portions 65 and 66 which conform in shape and are assembled in a matching relationship. More specifically, cover portion 65 is slidably mounted on hollow receptacle portion 67A and cover portion 66 is mounted on hollow receptacle portion 67B. Cover portion 65 functions in a manner similar to that described for cover portion 5 of FIG. 1 and thus will not be repeated here. The cover portion has a plurality of indentations 68 having side walls 69 and 70 and an apex 71. The apex 71 lies along a radius originating from receptacle axis 72. Each indentation 68 has a triangular cross-section defined by the side walls 69 and 70 that open toward the cover portion 65. The indentations of cover portions 65 and 66 form a closed area having a square cross-section for gripping tubing 73 held therebetween. Bolts 74 and 76 extend through cover portions 65 and 66 respectively. Bolt nuts 77 and 86 engage bolts 76 and 85 respectively and upon tightening urge cover portions 65 and 66 together thereby gripping tubing 73 between the cover portions. Similar bolting arrangements (not shown) are located symmetrically between the other indentations disposed on the cover portions. As may be apparent the structure of FIG. 10A provides for the gripping of varying sized tubing. Thus for larger sized tubing the cover portions will be held further apart whereas for smaller sized tubing the cover portions will be held closer together. Collar 78 is slidably mounted on receptacle portion 67A and locked in place by set screw 79. Similarly collar 80 is slidably mounted on receptacle portion 67B and locked in place by set screw 81. In such manner the connectors 65 and 66 are fixed in stationary condition on receptacles 67A and 67B, while gripping tubing 73 therebetween. Braces 82 and 83 shown only in FIG. 10A are coupled to the connector 64 either between the cover portions 65 and 66 as shown in FIG. 10A or upon the outer surfaces of the cover portions 65 and 66. Brace 82 is secured to the connector 64 by means of bolt 74, which passes through apertures 90 and 91, and nut 75 which when tightened, urges the cover plates 65 and 66 together. Similarly brace 83 is secured to the connector 64 by means of bolt 84, which passes through apertures 88 and 89, and nut 87 which when tightened urges the cover plates 65 and 66 together. Only two braces are shown, however, it is to be understood that three or four braces may be used depending upon "cell" configuration. As previously discussed the braces 82 and 83 are also connected to adjacent connectors for coupling such connectors together in a truss assembly.

The present invention relates to a connector for a tubular truss assembly which is formed of tubes loosely fit between selected adjacent ones of the connectors. The tubes are held in place either by a set screw in connector receptacles into which the tubes are mounted or by a tensioning element connected between connectors for urging the connectors together. The manner of coupling and securement provides for very rapid assembly, minimization of stress concentrations and turning connector assemblies to form non-planar structures.

You are an expert at summarizing long articles. Proceed to summarize the following text: [0001] This application is a continuation-in-part of copending application Ser. No. 10/000,678 filed on Oct. 30, 2001 BACKGROUND OF THE INVENTION [0002] The present invention relates to a connection in which an elongated strap or a connector having an elongated strap member is secured by a strap holder. Such straps and connectors are used in a variety of building applications, typically in connections that resist tension forces parallel to the main axes of the straps or strap members. A number of connectors with elongated strap members are in common use with a variety of structural members. [0003] The present invention relates to a connection in which a strap bridges a plurality of substantially parallel structural members and is secured by a strap holder, especially where an elongate utility strap is used, typically in pairs forming X bracing, to reinforce roof trusses against forces acting along the length of the roof. Single diagonal braces of this general type are also commonly used in walls in light wood frame construction, and might also be used to brace floor beams or other series of parallel structural members. SUMMARY OF THE INVENTION [0004] It is an object of the present invention to provide a secure connection between an elongated strap member and a structural member. The present invention improves on the prior art of simply nailing through the strap and into the structural member beneath it. The present invention provides a connection having a plurality of parallel structural members. The structural members are bridged by strap member, preferably light gauge steel. The end of the strap member is held in place by an overlapping strap holder. [0005] Fasteners hold the strap holder and the strap to the underlying structural member, with at least one passing through only the strap holder into the first side of the first structural member. [0006] The different emodiments of the present invention can improve the connections of a variety of connectors with strap members and many different structural members. BRIEF DESCRIPTION OF THE DRAWINGS [0007] [0007]FIG. 1 is an isometric view of a roof, showing three sections of roof trusses connected by strap members arranged in X patterns. [0008] [0008]FIG. 2 is an isometric view of a plurality of roof trusses, joined by perpendicular bracing and by connections of the present invention. [0009] [0009]FIG. 3 is a side elevation view of the preferred embodiment of the strap holder of the present invention. [0010] [0010]FIG. 4 is a top plan view of the preferred embodiment of the strap holder of the present invention. [0011] [0011]FIG. 5 is a side elevation view of the preferred embodiment of the strap holder of the present invention, perpendicular to the view of FIG. 3. [0012] [0012]FIG. 6 is a bottom plan view of the preferred embodiment of the strap holder of the present invention. [0013] [0013]FIG. 7 is a side elevation view of a roof truss showing a plurality of connections of the present invention, in particular the interface of first structural member, strap and strap holder. [0014] [0014]FIG. 8 is a side elevation view of the strap holder, strap member and first structural member of the present invention, connected by fasteners. [0015] [0015]FIG. 9 is an isometric view of an alternate preferred embodiment of the present invention, in which the plurality of substantially parallel structural members are wall studs. [0016] [0016]FIG. 10 is an isometric view of a second alternate preferred embodiment of the present invention, in which the plurality of substantially parallel structural members are floor joists. [0017] [0017]FIG. 11 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a header and the second structural member is a vertical wall stud. [0018] [0018]FIG. 12 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a header and the second structural member is a horizontal chord of a truss. [0019] [0019]FIG. 13 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a header and the second structural member is a horizontal beam. [0020] [0020]FIG. 14 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a truss and the second structural member is a cementitious member. [0021] [0021]FIG. 15 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a wall stud and the second structural member is a concrete foundation. [0022] [0022]FIG. 16 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a purlin and the second structural member is a cementitious wall. [0023] [0023]FIG. 17 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a stud and the second structural member is a cementitious member. [0024] [0024]FIG. 18 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a horizontally-disposed structural member and the second structural member is a cementitious member. [0025] [0025]FIG. 19 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is an angled structural member and the second structural member is a horizontally-disposed structural member. [0026] [0026]FIG. 20 is a perspective view of a preferred embodiment of the present invention, in which the first and second structural members are colinear. [0027] [0027]FIG. 21 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a header and the second structural member is a horizontal beam, and the top flange of the hanger is bent over to interface with the back of the header. [0028] [0028]FIG. 22 is a front elevation view of a preferred embodiment of the strap holder of the present invention. [0029] [0029]FIG. 23 is a top plan view of a preferred embodiment of the strap holder of the present invention. [0030] [0030]FIG. 24 is a side elevation view of a preferred embodiment of the strap holder of the present invention. [0031] [0031]FIG. 25 is a bottom plan view of a preferred embodiment of the strap holder of the present invention. [0032] [0032]FIG. 26 is a perspective view of a preferred embodiment of the present invention, showing attachment to three sides of the first structural member. [0033] [0033]FIG. 27 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a wall stud and the second structural member is a concrete foundation. [0034] [0034]FIG. 28 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a purlin and the second structural member is a cementitious wall. [0035] [0035]FIG. 29 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is a stud and the second structural member is a cementitious member. [0036] [0036]FIG. 30 is a perspective view of a preferred embodiment of the present invention, in which the first structural member is vertical wall stud and the second structural member is a header. [0037] [0037]FIG. 31 is a perspective view of a preferred embodiment of the present invention, in which the first and second structural members are colinear and strap holders of the present invention interface with both. [0038] [0038]FIG. 32 is a perspective view of a preferred embodiment of the present invention, in which the first and second structural members are colinear, the first structural member interfaces with one preferred embodiment of the present invention, and the second structural member interfaces with another preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0039] As best seen in FIG. 2, the preferred form of the present invention is a connection 1 comprising a plurality of substantially parallel structural members 2 , a first structural member 3 having a first side 4 , a strap member 5 having an upper surface 6 , a lower surface 7 , a first side edge 8 , a second side edge 9 , and a first end edge 10 , a strap holder 12 having an upper face 13 and a lower face 14 , the lower face 14 being dimensioned to interface with the first side 4 of the first structural member 3 and attached only to the first structural member 3 of the plurality of structural members 2 , and a plurality of fasteners 15 . The lower surface 7 of the strap member 5 interfaces with the first side 4 of the first structural member 3 , the lower face 14 of the strap holder 12 interfaces with the upper surface 6 of the strap member 5 , extending beyond the first side edge 8 to interface with the first side 4 of the first structural member 3 , at least one of the plurality of fasteners 15 passes through both the strap holder 12 and the strap member 5 and into the first side 4 of the first structural member 3 , at least one of the plurality of fasteners 15 passes through only the strap holder 12 into the first side 4 of the first structural member 3 , and the strap member 5 crosses over the plurality of substantially parallel structural members 2 . As shown in FIG. 2, in the preferred embodiment of the present invention, the substantially parallel structural members 2 are the top members of roof trusses 11 . The connection 1 of the present invention is paired to create X bracing that reinforces the roof 16 against forces acting primarily along the length of the roof 16 , which is otherwise relatively rigid where it joins the wall below, which is typically reinforced by sheathing against shear forces acting along the length of the wall. As shown in FIG. 1, a number of areas of the roof 16 are reinforced with X bracing, which is often required by building codes. [0040] As best shown in FIG. 7 and in detail in FIG. 8 in the preferred embodiment the first structural member 3 further comprises a second side 17 and a first juncture 18 between the first side 4 and the second side 17 . The strap member 5 is bent over the first juncture 18 and interfaces with the second side 17 . [0041] As best shown in FIG. 3, FIG. 4, FIG. 5, and FIG. 6, in the preferred embodiment the strap holder 12 additionally comprises a first transition line 19 and a second transition line 20 , the first transition line 19 and the second transition line 20 dividing the upper face 13 and the lower face 14 into a first attachment portion 21 , a second attachment portion 22 , and a first securement portion 23 between the first transition line 19 and the second transition line 20 , and wherein the first securement portion 23 is dimensioned to closely interface with the upper surface 6 of the strap member 5 , the first transition line 19 closely parallel to the first side edge 8 and the second transition line 20 closely parallel to the second side edge 9 . In the preferred embodiment, the first transition line 19 and the second transition line 20 are double bends that create a raised securement portion 23 that bisects the middle of the strap holder 12 . [0042] As best shown in FIG. 7 and FIG. 8, in the preferred embodiment one or more of the plurality of fasteners 15 passes through the first attachment portion 21 into the first side 4 of the first structural member 3 , one or more of the plurality of fasteners 15 passes through the second attachment portion 22 into the first side 4 of the first structural member 3 , and one or more of the plurality of fasteners 15 passes through the first securement portion 23 , through the strap member 5 , and into the first side 4 of the first structural member 3 . [0043] As shown in FIG. 2, in the preferred embodiment, the plurality of substantially parallel structural members 2 and the first structural member 3 are the top chords of roof trusses 11 and the top chords of roof trusses 25 are made of wood. As shown in FIG. 10, in an alternate preferred embodiment, the plurality of substantially parallel structural members 2 and the first structural member 3 are floor beams, and the floor beams are made of wood. As shown in FIG. 9, in another alternate preferred embodiment, the plurality of substantially parallel structural members 2 and the first structural member 3 are wall studs. Notwithstanding the above, the substantially parallel structural members 2 may be any such series of structural members, and may made of any material, such as steel. In the preferred embodiment, the fasteners 15 are nails, although they may be screws, bolts or any other type of pin-like fastener. [0044] In the preferred embodiment, the strap member 5 and strap holder 12 are both formed from light gauge steel, but either or both may be formed from other metals or plastics, or any other material that may be formed into the necessary shapes. [0045] In the preferred embodiment, the strap holder 12 is formed with a plurality of fastener openings 24 and the strap member 5 is also formed with a plurality of fastener openings 25 . [0046] As best shown in FIG. 2, in an alternate preferred embodiment the present invention is a connection 1 comprising a first structural member 3 , having a first side 4 , a second side 17 , and a third side 26 , a second structural member 27 , a connector 28 having an elongated strap member 5 , the strap member 5 having an upper surface 6 , a lower surface 7 , a first side edge 8 , a second side edge 9 , and a first end edge 10 , a strap holder 12 having an upper face 13 and a lower face 14 , the lower face 14 being dimensioned to interface with the first side 4 of the first structural member 3 the strap holder 12 being not attached to the second structural member 27 , and a first plurality of fasteners 15 . The lower surface 7 of the strap member 5 interfaces with the first side 4 of the first structural member 3 , the lower face 14 of the strap holder 12 interfaces with the upper surface 6 of the strap member 5 , extending beyond the first side edge 8 of the strap member 6 to interface with the first structural member 3 , at least one of the first plurality of fasteners 15 passes through both the strap holder 12 and the strap member 5 and into the first side 4 of the first structural member 3 , at least one of the first plurality of fasteners 15 passes through only the strap holder 12 into the first structural member 3 , and the connector 28 having the strap member 5 connects to the second structural member 27 . [0047] As best shown in FIG. 8, preferably at least one of the first plurality of fasteners 15 passes through only the strap holder 12 into the first side 4 of the first structural member 3 . [0048] As best shown in FIGS. 3, 4, 5 , and 6 , preferably the strap holder 12 additionally comprises a first transition line 19 and a second transition line 20 , the first transition line 19 and the second transition line 20 dividing the upper face 13 and the lower face 14 into a first attachment portion 21 , a second attachment portion 22 , and a first securement portion 23 between the first transition line 19 and the second transition line 20 . The first securement portion 23 is dimensioned to closely interface with the upper surface 6 of the strap member 5 , the first transition line 19 being closely parallel to the first side edge 8 of the strap and the second transition line 20 being closely parallel to the second side 17 edge 9 of the strap. [0049] As best shown in FIGS. 7 and 8, preferably one or more of the first plurality of fasteners 15 passes through the first attachment portion 21 into the first side 4 of the first structural member 3 , one or more of the first plurality of fasteners 15 passes through the second attachment portion 22 into the first side 4 of the first structural member 3 , and one of more of the first plurality of fasteners 15 passes through the first securement portion 23 , through the strap member 5 , and into the first side 4 of the first structural member 3 . [0050] As best shown in FIG. 11, in a preferred embodiment the first structural member 3 is a header and the first side 4 of the first structural member 3 is a vertical face of a header, the connector 28 and the strap member 5 are an elongated metal strap, the second structural member 27 is a vertical wall stud, and a second plurality of fasteners 31 attach the elongated metal strap to the vertical wall stud. [0051] As best shown in FIG. 12, in a preferred embodiment the first structural member 3 is a header and the first side 4 of the first structural member 3 is a horizontal top face of the header, the connector 28 is a truss hanger and the strap member 5 is a top flange of the truss hanger, and the second structural member 27 is a horizontal chord of a truss. [0052] As best shown in FIG. 13, in a preferred embodiment the first structural member 3 is a header and the first side 4 of the first structural member 3 is a horizontal top face of the header, the connector 28 is a joist hanger and the strap member 5 is a top flange of the joist hanger, and the second structural member 27 is a horizontal beam [0053] As best shown in FIG. 14, in a preferred embodiment the first structural member 3 is a truss member and the first side 4 of the first structural member 3 is a vertical face of the truss member, the connector 28 is an embedded truss anchor and the strap member 5 is a strap portion of the embedded truss anchor, and the second structural member 27 is a cementitious member. [0054] As best shown in FIG. 15, in a preferred embodiment the first structural member 3 is a wall stud and the first side 4 of the first structural member 3 is a vertical face of the wall stud, the connector 28 is a strap holdown and the strap member 5 is a strap portion of the strap holdown, the second structural member 27 is a concrete foundation. [0055] As best shown in FIG. 16, in a preferred embodiment the first structural member 3 is a purlin and the first side 4 of the first structural member 3 is a horizontal top face of the purlin, the connector 28 is a purlin anchor and the strap member 5 is a strap portion of the purlin anchor, and the second structural member 27 is cementitious wall. [0056] As best shown in FIG. 17, in a preferred embodiment the first structural member 3 is a stud and the first side 4 of the first structural member 3 is a vertical face of the stud, the connector 28 and the strap member 5 are an elongated metal strap, the second structural member 27 is a cementitious member, and a second plurality of fasteners 31 attaches the elongated metal strap to the cementitious member. [0057] As best shown in FIG. 18, in a preferred embodiment the first structural member 3 is a horizontally-disposed structural member and the first side 4 of the first structural member 3 is a vertical face of the horizontally-disposed structural member, the connector 28 and the strap member 5 are an elongated bent strap, the second structural member 27 is a cementitious member, and a second plurality of fasteners 31 attach the elongated bent strap to the cementitious member. [0058] As best shown in FIG. 19, in a preferred embodiment the first structural member 3 is an angled structural member and the first side 4 of the first structural member 3 is a vertical face of the angled structural member, and the connector 28 and the strap member 5 are an elongated bent strap, the second structural member is a horizontally-disposed structural member, and a second plurality of fasteners 31 attaches the elongated bent strap to the horizontally-disposed structural member. [0059] As best shown in FIG. 20, in a preferred embodiment the first structural member 3 and the second structural member 27 are substantially colinear, the connector and the strap member 5 are an elongated metal strap; and a second strap holder 12 connects the elongated strap to the second structural member 27 in conjunction with a second plurality of fasteners 31 . [0060] As best shown in FIG. 21, in a preferred embodiment the first structural member 3 is a header and the first side 4 of the first structural member 3 is a vertical face of the header, the connector 28 is a joist hanger and the strap member 5 is a top flange of the joist hanger, and the second structural member 27 is a horizontal beam. [0061] As best shown in FIG. 26, in a preferred embodiment at least one of the first plurality of fasteners 15 passes through only the strap holder 12 into the second side 17 of the first structural member 3 . [0062] As best shown in FIGS. 22, 23, 24 , 25 and 26 , in a preferred embodiment the strap holder 12 additionally comprises a first junction 29 and a second junction 30 , the first junction 29 and the second junction 30 dividing the upper face 13 and the lower face 14 into a first attachment portion 21 , a second attachment portion 22 , and a first securement portion 23 between the first junction 29 and the second junction 30 . The first attachment portion 21 is dimensioned to closely interface with the second side 17 of the first structural member 3 , the second attachment portion 22 is dimensioned to closely interface with the third side 26 of the first structural member 3 , the first and second attachment portion 22 s are substantially parallel to each other and substantially perpendicular to the first securement portion 23 . [0063] As best shown in FIG. 26, in a preferred embodiment one or more of the first plurality of fasteners 15 passes through the first attachment portion 21 into the second side 17 of the first structural member 3 , one or more of the first plurality of fasteners 15 passes through the second attachment portion 22 into the third side 26 of the first structural member 3 , and one of more of the first plurality of fasteners 15 passes through the first securement portion 23 , through the strap member 5 , and into the first side 4 of the first structural member 3 . [0064] As best shown in FIG. 27, in a preferred embodiment the first structural member 3 is a wall stud and the first side 4 of the first structural member 3 is a vertical face of the wall stud, the connector 28 is a strap holdown and the strap member 5 is a strap portion of the strap holdown, and the second structural member 27 is a concrete foundation. [0065] As best shown in FIG. 28, in a preferred embodiment the first structural member 3 is a purlin and the first side 4 of the first structural member 3 is a horizontal top face of the purlin, the connector 28 is a purlin anchor and the strap member 5 is a strap portion of the purlin anchor, and the second structural member 27 is cementitious wall. [0066] As best shown in FIG. 29, in a preferred embodiment the first structural member 3 is a stud and the first side 4 of the first structural member 3 is a vertical face of the stud, the connector 28 and the strap member 5 are an elongated metal strap, the second structural member 27 is a cementitious member, and a second plurality of fasteners 31 attaches the elongated metal strap to the cementitious member. [0067] As best shown in FIG. 30, in a preferred embodiment the first structural member 3 is a post and the first side 4 of the first structural member 3 is a vertical face of the post, the connector 28 and the strap member 5 are an elongated metal strap, the second structural member 27 is a header, and a second plurality of fasteners 31 attach the elongated metal strap to the header. [0068] As best shown in FIG. 31, in a preferred embodiment the first structural member 3 and the second structural member 27 are substantially colinear, the strap member 5 is an elongated metal strap; and a second strap holder 12 connects the elongated strap to the second structural member 27 in conjunction with a second plurality of fasteners 31 . [0069] As best shown in FIG. 32, in a preferred embodiment the first structural member 3 and the second structural member 27 are substantially colinear, the strap member 5 is an elongated metal strap, a second strap holder 12 connects the elongated strap to the second structural member 27 in conjunction with a second strap holder 12 . The second strap holder 12 additionally comprises a first transition line 19 and a second transition line 20 , the first transition line 19 and the second transition line 20 dividing the upper face 13 and the lower face 14 into a first attachment portion 21 , a second attachment portion 22 , and a first securement portion 23 between the first transition line 19 and the second transition line 20 . The first securement portion 23 is dimensioned to closely interface with the upper surface 6 of the strap member 5 , the first transition line 19 being closely parallel to the first side edge 8 of the strap and the second transition line 20 being closely parallel to the second side 17 edge 9 of the strap.

A connection in which an elongated strap or a connector having an elongated strap member is secured by a strap holder. Such straps and connectors are used in a variety of building applications, typically in connections that resist tension forces parallel to the main axes of the straps or strap members. A number of connectors with elongated strap members are in common use with a variety of structural members.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND [0001] Buildings and other habitable environments create a barrier to weather and other elements. Many buildings are designed to keep out water in the form of rain, snow, and ice. Many buildings create an internal environment with a temperature that is different than the external environment. In a hot climate or season, a building may have air conditioning to provide a lower internal temperature than the outside temperature. Similarly, in a cold climate or season, a building may have internal heating to provide a warmer temperature inside than out. [0002] When temperature differentials between internal and external environments exist, there is a possibility of condensation, high humidity, and other moisture related issues in building design. Further, many buildings may be designed with various mechanisms to allow air exchange between the internal and external environments. SUMMARY [0003] A barrier membrane for use in building construction may be manufactured by forming a polymeric film coating on release paper or film; or on nonwoven textiles, paper, fiberglass, or other structural substrate to improve tensile strength. Alternatively, the film may be fully or partially formed and then bonded to a structural substrate. A porous film coating or laminate may be formed using PVDF, PVC, and various polyolefins. A typical membrane may be less than 100 mil thick and greater than 50% porous, and may have a barrier to a passage of water in the liquid phase while retaining gas permeability. Some embodiments may contain active ingredients to combat bacterial or fungal growth, repel insects, or absorb environmental pathogens. The active ingredients may be applied after the porous film is manufactured or may be incorporated during the film manufacturing process. [0004] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS [0005] In the drawings, [0006] FIG. 1 is a diagram illustration of an embodiment showing a cross-section of reinforced porous material. [0007] FIG. 2 is a flowchart illustration of an embodiment showing a method for forming a porous material. [0008] FIG. 3 is a diagram illustration of an embodiment showing a process for continuous manufacturing of reinforced porous material. [0009] FIG. 4 is a diagram illustration of an embodiment showing a process for a dip method of continuous manufacturing of reinforced porous material. [0010] FIG. 5 is a diagram illustration of an embodiment showing a one-sided laminating method for manufacturing a reinforced porous film. [0011] FIG. 6 is a diagram illustration of an embodiment showing a two-sided laminating method for manufacturing a reinforced porous film. [0012] FIG. 7 is a flowchart illustration of an embodiment showing a method for forming a porous material with loading. [0013] FIG. 8 is a diagram illustration of an embodiment showing a cross-section of batting insulation with a vapor barrier. [0014] FIG. 9 is a diagram illustration of an embodiment showing a cross-section of an exterior wall from a top view. [0015] FIG. 10 is a diagram illustration of an embodiment showing a cross-section of a second construction for an exterior wall from a top view. [0016] FIG. 11 is a diagram illustration of an embodiment showing a cross-section of a roofing system. [0017] FIG. 12 is a diagram illustration of an embodiment showing a cross-section of a crawlspace. DETAILED DESCRIPTION [0018] A reinforced porous film may be constructed through various processes and using various formulations to be used in different applications within the building and construction trades. The reinforced films may be used as a barrier film within an exterior wall, roof, or floor, as a vapor barrier for insulation, and for other uses. The reinforced films may also be used for interior applications, such as wallboard, wall paper, underneath plaster, underneath flooring materials, and other applications. [0019] In some applications, the porous film may be loaded with various materials that may prevent or inhibit fungal or bacterial growth, repel insects, or otherwise prevent microbes or pests from passing through. Some applications may include materials that may absorb environmental pathogens. Such materials may be included in the porous film by including the materials during the formation of the porous material or after the porous material has been formed. [0020] A reinforced porous film may be created by several methods. Porous films by nature may be structurally weak, especially films with high porosity. A reinforced film may be considerably more structurally sound than an unreinforced film. Increased mechanical properties may help during handling and manufacturing of the film into various products, as well as increased structural properties of an end product. [0021] One method for producing a reinforced porous film may be to create the porous material with a reinforcement. For example, a solution used to create the porous material may be cast or sprayed onto the reinforcement. In another example, the reinforcement may be dipped into the solution. [0022] Another method for producing a reinforced porous film may be to form a porous film and subsequently bond the porous film to a reinforcement. The bonding may be accomplished using mechanical interlocking, heat fusing, adhesives, or any other mechanism. [0023] The reinforcement may be any type of woven or nonwoven material, perforated film, or any other web material. For the purposes of this specification, any references to any type of reinforcing web shall be interpreted to mean any type of reinforcing web, including nonwoven and woven reinforcement. [0024] Specific embodiments of the subject matter are used to illustrate specific aspects. The embodiments are by way of example only, and are susceptible to various modifications and alternative forms. The appended claims are intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims. [0025] Throughout this specification, like reference numbers signify the same elements throughout the description of the figures. [0026] When elements are referred to as being “connected” or “coupled,” the elements can be directly connected or coupled together or one or more intervening elements may also be present. In contrast, when elements are referred to as being “directly connected” or “directly coupled,” there are no intervening elements present. [0027] FIG. 1 is a schematic diagram of an embodiment 100 showing a cross section of porous material that may be formed using a solution of a polymer dissolved in a solvent and a miscible pore forming agent that has a higher surface energy. The porous material 102 and 104 is shown on both sides of a web 106 . [0028] FIG. 1 is not to scale and is a schematic diagram. In some embodiments, the porous material 102 and 104 may impregnate the non-woven web 106 . Such embodiments may have partial impregnation or complete impregnation of porous material 102 and 104 into the thickness of the non-woven web 106 . Some embodiments may have mechanical or chemical adhesion of the porous material 102 and 104 to the surface of the non-woven web 106 . Other embodiments may vary in cross section based on the specific manufacturing process used and may have full impregnation or very little mechanical interlocking between the layers. [0029] Embodiment 100 may be manufactured by several different methods. In some cases, the porous material 102 and 104 may be formed separately and bonded to the non-woven reinforcement 106 . In other cases, the porous material 102 and 104 may be formed from a solution that may be applied to the reinforcement 106 in a liquid form and processed to yield the porous material 102 and 104 with the reinforcement 106 . [0030] FIG. 2 is a flowchart diagram of an embodiment 200 showing a method for forming a porous material. Embodiment 200 is a general method, examples of which are discussed below. [0031] In block 202 , a solution may be formed with a polymer dissolved in a first liquid and a second liquid that may act as a pore forming agent. The liquids may be selected based on boiling points or volatility and surface tension so that when processed, the polymer is formed with a high porosity. Examples of such liquids are discussed below. [0032] After forming the solution in block 202 , the solution is applied to a carrier in block 204 . The carrier may be any type of material. In some cases, a flat sheet of porous material may be cast onto a table top, which acts as a carrier in a batch process. In other cases, a film such as a polymer film, treated or untreated kraft paper, aluminum foil, or other backing or carrier material may be used in a continuous process. In such cases, a porous film may be manufactured and attached to a reinforcing web in a secondary process. In still other cases, the carrier material may be a nonwoven, woven, perforated, or other reinforcing web. In such cases, the solution may be applied by dipping, spraying, casting, extruding, pouring, spreading, or any other method of applying the solution. [0033] The reinforcing web may be any type of reinforcement, including polymer based nonwoven webs, paper products, and fiberglass. In some cases, a woven material may be used with natural or manmade fibers, while in other cases, a solid film may be perforated and used as a reinforcing web. [0034] In block 206 , enough of the primary liquid may be removed so that the dissolved polymer may begin to gel. In some embodiments, some, most, or substantially all of the primary liquid may be removed in block 206 . As the polymer begins to gel, the mechanical structure of the material may begin to take shape and the porosity may begin to form. During this time, the material may have some mechanical properties so that different mechanisms may be used to remove any remaining primary liquid and the secondary liquid. [0035] The secondary liquid may be removed in block 208 . During the gelling process of block 206 , the differences in surface tension between the various materials may allow the secondary liquid to coalesce and form droplets, around which the polymer may gel as the first liquid is removed. After or as the polymer solidifies, the second liquid may be removed. In some cases, the boiling point or volatility of the two liquids may be selected so that the primary liquid evaporates prior to the secondary liquid. [0036] The mechanisms for removing the primary and secondary liquids may be any type of suitable mechanism for removing a liquid. In many cases, the primary liquid may be removed by a unidirectional mass transfer mechanism such as evaporation, wicking, blotting, mechanical compression or others. Some methods may use bidirectional mass transfer such as rinsing or washing. In some cases, one method may be used to remove the primary liquid and a second method may be used for the secondary liquid. For example, the primary liquid may be at least partially removed by evaporation while the remaining primary liquid and secondary liquid may be removed by rinsing or mechanically squeezing the material. [0037] Three embodiments are presented below of formulations and methods of production for porous material. [0038] In a first embodiment, the porous material may be formed by first forming a layer of a polymer solution on a substrate, wherein the polymer solution may comprise two miscible liquids and a polymer material dissolved therein, wherein the two miscible liquids may comprise (i) a principal solvent liquid that may have a surface tension at least 5% lower than the surface energy of the polymer and (ii) a second liquid that may have a surface tension at least 5% greater than the surface energy of the polymer. Second, a gelled polymer may be produced from the layer of polymer solution under conditions sufficient to provide a non-wetting, high surface tension solution within the layer of polymer solution; and, thirdly, rapidly removing the liquid from the film of gelled polymer by unidirectional mass transfer without dissolving the gelled polymer to produce the strong, highly porous, microporous polymer 102 and 104 . [0039] In a second embodiment, the porous material 104 may be produced using a method comprising: [0040] (i) preparing a solution of one or more polymers in a mixture of a principal liquid which is a solvent for the polymer and a second liquid which is miscible with the principal liquid, wherein (i) the principal liquid may have a surface tension at least 5% lower than the surface energy of the polymer, (ii) the second liquid may have a surface tension at least 5% higher than the surface energy of the polymer, (iii) the normal boiling point of the principal liquid is less than 125° C. and the normal boiling point of the second liquid is less than about 160° C., (iv) the polymer may have a lower solubility in the second liquid than in the principal liquid, and (v) the solution may be prepared at a temperature less than about 20° C. above the normal boiling point of the principal liquid and while precluding any substantial evaporation of the principal liquid; [0041] (ii) reducing the temperature of the solution by at least 5° C. to a temperature between the normal boiling point of the principal liquid and the temperature of the substrate upon the solution is to be cast; [0042] (iii) casting the polymer solution onto a high surface energy substrate to form a liquid coating thereon, said substrate having a surface energy greater than the surface energy of the polymer; and [0043] (iv) removing the principal liquid and the second liquid from the coating by unidirectional mass transfer without use of an extraction bath, (ii) without re-dissolving the polymer, and (iii) at a maximum air temperature of less than about 100° C. within a period of about 5 minutes, to form the strong, highly porous, thin, symmetric polymer membrane. [0044] In a third embodiment, the porous material 104 may be produced by a method comprising: [0045] (i) dissolving about 3 to 20% by weight of a polymer in a heated multiple liquid system comprising (a) a principal liquid which is a solvent for the polymer and (b) a second liquid to form a polymer solution, wherein (i) the principal liquid may have a surface tension at least 5% lower than the surface energy of the polymer, (ii) the second liquid may have a surface tension at least 5% greater than the surface energy of the polymer; and (iii) the polymer may have a lower solubility in the second liquid than it has in the principal solvent liquid; [0046] (ii) reducing the temperature of the solution by at least 5° C. to between the normal boiling point of the principal liquid and the temperature of the substrate upon which it will be cast; [0047] (iii) casting a film of the fully dissolved solution onto a substrate which may have a higher surface energy than the surface energy of the polymer; [0048] (iv) precipitating the polymer to form a continuous gel phase while maintaining at least 70% of the total liquid content of the initial polymer solution, said precipitation caused by a means selected from the group consisting of cooling, extended dwell time, solvent evaporation, vibration, or ultrasonics; and [0049] (v) removing the residual liquids without causing dissolution of the continuous gel phase by unidirectional mass transfer without any extraction bath, at a maximum film temperature which is less than the normal boiling point of the lowest boiling liquid, and within a period of about 5 minutes, to form a strong, highly porous, thin, symmetric polymer membrane. [0050] The preceding embodiments are examples of different methods by which a porous material may be formed from a liquid solution to a porous polymer. Different embodiments may be used to create the porous material 102 and 104 and such embodiments may contain additional steps or fewer steps than the embodiments described above. Other embodiments may also use different processing times, concentrations of materials, or other variations. [0051] Each of the embodiments of porous material 102 and 104 may begin with the formation of a solution of one or more soluble polymers in a liquid medium that comprises two or more dissimilar but miscible liquids. To form highly porous products, the total polymer concentration may generally be in the range of about 3 to 20% by weight. Lower polymer concentrations of about 3 to 10% may be preferred for the preparation of membranes having porosities greater than 70%, preferably greater than 75%, and most preferably greater than 80% by weight. Higher polymer concentrations of about 10 to 20% may be more useful to prepare slightly lower porosity membranes, i.e. about 60 to 70%. [0052] A suitable temperature for forming the polymer solution may generally range from about 40° C. up to about 20° above the normal boiling point of the principal liquid, preferably about 40 to 80° C., more preferably about 50° C. to about 70° C. A suitable pressure for forming the polymer solution may generally range from about 0 to about 50 psig. In some embodiments, the polymer solution may be formed in a vacuum. Preferably a sealed pressurized system is used. [0053] The material 102 may be formed in the presence of at least two dissimilar but miscible liquids to form the polymer solution from which a polymer film may be cast. The first “principal” liquid may be a better solvent for the polymer than the second liquid and may have a surface tension at least 5%, preferably at least 10%, lower than the surface energy of the polymer involved. The second liquid may be a solvent or a non-solvent for the polymer and may have a surface tension at least 5%, preferably at least 10%, greater than the surface energy of the polymer. [0054] The principal liquid may be at least 70%, preferably about 80 to 95%, by weight of the total liquid medium. The principal liquid may dissolve the polymer at the temperature and pressure at which the solution may be formed. The dissolution may generally take place near or above the boiling temperature of the principal liquid, usually in a sealed container to prevent evaporation of the principal liquid. The principal liquid may have a greater solvent strength for the polymer than the second liquid. Also, the principal liquid may have a surface tension at least about 5%, preferably at least about 10%, lower than the surface energy of the polymer. The lower surface tension may lead to better polymer wetting and hence greater solubilizing power. [0055] The second liquid, which may generally represent about 1 to 10% by weight of the total liquid medium, may be miscible with the first liquid. The second liquid may or may not dissolve the polymer as well as the first liquid at the selected temperature and pressure. The second liquid may have a higher surface tension than the surface energy of the polymer. Preferably, the second liquid may or may not wet the polymer at the gelation temperature though it may wet the polymer at more elevated temperatures. [0056] Table A and Table B identify some specific principal and second liquids that may be used with typical polymers, especially including PVDF. PVDF may be used as a homopolymer or as a copolymer with hexofloropropolyne. Table A lists liquids that have at least some degree of solubility towards PVDF (surface energy of 35 dyne/cm), which may produce the dissolved polymer solution in the first step of the process. Ideally, a liquid may be selected from Table A that has solubility limits between 1% and 50% by weight of polymer at a temperature within the range of about 20 and 90° C. The liquids in Table B, on the other hand, may have lower polymer solubility than those in Table A, but may be selected because they have a higher surface tension than both the principal liquid and the polymers that may be dissolved in the solution made with liquid(s) from Table A. [0057] Tables A and B represent typical examples of suitable liquids that may be used to create a porous material 102 and 104 . Other embodiments may use different liquids as a principal liquid or second liquid. [0058] Examples of suitable liquids for use as the principal liquid, along with their boiling point and surface tensions are provided in Table A below. The table is arranged in order of increasing boiling point, which is a useful parameter for achieving rapid gelling and removal of the liquid during the film formation step. In some applications, a lower boiling point may be preferred. [0000] TABLE A Normal Boiling Surface Energy, Principal Liquid Point, EC dynes/cm methyl formate 31.7 24.4 acetone (2-propanone) 56 23.5 methyl acetate 56.9 24.7 Tetrahydrofuran 66 26.4 ethyl acetate 77 23.4 methyl ethyl ketone (2-butanone) 80 24 Acetonitrile 81 29 dimethyl carbonate 90 31.9 1,2-dioxane 100 32 Toluene 110 28.4 methyl isobutyl ketone 116 23.4 [0059] Examples of suitable liquids for use as the second liquid, along with their boiling point and surface tensions are provided in Table B below. This table is arranged in order of increasing surface tension as higher surface tension may result in optimum pore size distributions during the gelling and liquid removal steps of the process. [0000] TABLE B Normal boiling Surface Energy, Second Liquid point, ° C. dynes/cm nitromethane 101 37 bromobenzene 156 37 formic acid 100 38 pyridine 114 38 ethylene bromide 131 38 3-furaldehyde 144 40 bromine 59 42 tribromomethane 150 42 quinoline 24 43 nitric acid (69%) 86 43 water 100 72.5 [0060] The porous material may be formed by using a liquid medium for forming the polymer solution. The liquid medium may be rapidly removable at a sufficiently low temperature so that the second liquid may be removed without re-dissolving the polymer during the liquid removal process. The liquid medium may or may not be devoid of plasticizers. The liquids that form the liquid medium may be relatively low boiling point materials. In many embodiments, the liquids may boil at temperatures less than about 125° C., preferably about 100° C. and below. Somewhat higher boiling point liquids, i.e. up to about 160° C., may be used as the second liquid if at least about 60% of the total liquid medium is removable at low temperature, e.g. less than about 50° C. The balance of the liquid medium can be removed at a higher temperature and/or under reduced pressure. Suitable removal conditions depend upon the specific liquids, polymers, and concentrations utilized. [0061] Preferably the liquid removal may be completed within a short period of time, e.g. less than 5 minutes, preferably within about 2 minutes, and most preferably within about 1.5 minutes. Rapid low temperature liquid removal, preferably using air flowing at a temperature of about 80° C. and below, most preferably at about 60° C. and below, without immersion of the membrane into another liquid has been found to produce a membrane with enhanced uniformity. The liquid removal may be done in a tunnel oven with an opportunity to remove and/or recover flammable, toxic or expensive liquids. The tunnel oven temperature may be operated at a temperature less than about 90° C., preferably less than about 60° C. [0062] The polymer solution may become supersaturated in the process of film formation. Generally cooling of the solution will cause the supersaturation. Alternatively, the solution may become supersaturated after film formation by means of evaporation of a portion of the principal liquid. In each of these cases, a polymer gel may be formed while there is still sufficient liquid present to generate the desired high void content in the resulting polymer film when that remaining liquid is subsequently removed. [0063] After the polymer solution has been prepared, it may then be formed into a thin film. The film-forming temperature may be preferably lower than the solution-forming temperature. The film-forming temperature may be sufficiently low that a polymer gel may rapidly form. That gel may then be stable throughout the liquid removal procedure. A lower film-forming temperature may be accomplished, for example, by pre-cooling the substrate onto which the solution is deposited, or by self-cooling of the polymer solution by controlled evaporation of a small amount of the principal liquid. [0064] The film-forming step may occur at a lower temperature (and often at a lower pressure) than the solution-forming step. Commonly, it may occur at or about room temperature. However, it may occur at any temperature and pressure if the gelation of the polymer is caused by means other than cooling, such as by slight drying, extended dwell time, vibrations, or the like. Application as a thin film may allow the polymer to gel in a geometry defined by the interaction of the liquids of the solution. [0065] The thin film may be formed by any suitable means. Extrusion or flow through a controlled orifice or by flow through a doctor blade may be commonly used. The substrate onto which the solution may be deposited may have a surface energy higher than the surface energy of the polymer. Examples of suitable substrate materials (with their surface energies) include copper (44 dynes/cm), aluminum (45 dynes/cm), glass (47 dynes/cm), polyethylene terephthalate (44.7 dynes/cm), and nylon (46 dynes/cm). In some cases a metal, metalized, or glass surface may be used. More preferably the metalized surface is an aluminized polyalkylene such as aluminized polyethylene and aluminized polypropylene. [0066] In view of the thinness of the films, the temperature throughout may be relatively uniform, though the outer surface may be slightly cooler than the bottom layer. Thermal uniformity may enable the subsequent polymer precipitation to occur in a more uniform manner. [0067] The films may be cooled or dried in a manner that prevents coiling of the polymer chains. Thus the cooling/drying may be conducted rapidly, i.e. within about 5 minutes, preferably within about 3 minutes, most preferably within about 2 minutes, because a rapid solidification of the spread polymer solution facilitates retention of the partially uncoiled orientation of the polymer molecules when first deposited from the polymer solution. [0068] The process may entail producing a film of gelled polymer from the layer of polymer solution under conditions sufficient to provide a non-wetting, high surface tension solution within the layer of polymer solution. Preferably gelation of the polymer into a continuous gel phase occurs while maintaining at least 70% of the total liquid content of the initial polymer solution. More particularly, the precipitation of the gelled polymer is caused by a means selected from a group consisting of cooling, extended dwell time, solvent evaporation, vibration, or ultrasonics. Then, the balance of the liquids may be removed by a unidirectional process, usually by evaporation, from the formed film to form a strong micro-porous membrane of geometry controlled by the combination of the two liquids in the medium. In some embodiments, a liquid bath may be used to extract the liquids from the membrane. In other embodiments, the liquid materials may evaporate at moderate temperatures, i.e. at a temperature lower than that used for the polymer dissolution to prepare the polymer solution. The reduced temperature may be accomplished by the use of cool air or even the use of forced convection with cool to slightly warmed air to promote greater evaporative cooling. [0069] The interaction among the two liquids (with their different surface tension characteristics) and the polymer (with a surface energy intermediate the surface tensions of the liquids) may yield a membrane with high porosity and relatively uniform pore size throughout its thickness. The surface tension forces may act at the interface between the liquids and the polymer to give uniformity to the cell structure during the removal step. The resulting product may be a solid polymeric membrane with relatively high porosity and uniformity of pore size. The strength of the membrane in some embodiments may be surprisingly high, due to the more linear orientation of polymer molecules. [0070] The ratio of the principal liquid to the second liquid at the point of gelation may be adjusted such that the surface tension of the composite liquid phase may be greater than the surface energy of the polymer. The calculation of the composite liquid surface tension can be predicted based upon the mol fractions of liquids, as defined in “Surface Tension Prediction for Liquid Mixtures,” AlChE Journal, vol 44, no. 10, p. 2324, 1998, the subject matter of which is incorporated herein by reference. [0071] Thermodynamic calculations show that adiabatic cooling of a solution can be significant initially and that the temperature gradient through such a film is very small. The latter may be considered responsible for the exceptional uniformity obtained using these methods. [0072] The polymers used to produce the microporous membranes of the present invention may be organic polymers. Accordingly, the microporous polymers comprise carbon and a chemical group selected from hydrogen, halogen, oxygen, nitrogen, sulfur and a combination thereof. In a preferred embodiment, the composition of the microporous polymer may include a halogen. Preferably, the halogen is selected from the group consisting of chloride, fluoride, and a mixture thereof. [0073] Suitable polymers for use herein may be include semi-crystalline or a blend of at least one amorphous polymer and at least one crystalline polymer. [0074] Preferred semi-crystalline polymers may be selected from the group consisting of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyvinyl chloride, polyvinylidene chloride, chlorinated polyvinyl chloride, polymethyl methacrylate, and mixtures of two or more of these semi-crystalline polymers. [0075] In some embodiments, the products produced by the processes described herein may be used as a battery separator. For this use, the polymer may comprise a polymer selected from the group consisting of polyvinylidene fluoride (PVDF), polylvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polyvinyl chloride, and mixtures thereof. Still more preferably the polymer may comprise at least about 75% polyvinylidene fluoride. [0076] The “MacMullin” or “McMullin” Number measures resistance to ion flow is defined in U.S. Pat. No. 4,464,238, the subject matter of which is incorporated herein by reference. The MacMullin Number is “a measure of resistance to movement of ions. The product of MacMullin Number and thickness defines an equivalent path length for ionic transport through the separator. The MacMullin Number appears explicitly in the one-dimensional dilute solution flux equations which govern the movement of ionic species within the separator; it is of practical utility because of the ease with which it is determined experimentally.” The lower a MacMullin Number the better for battery separators, the better. Products using these techniques may have a low MacMullin number, i.e. about 1.05 to 3, preferably about 1.05 to less than 2, most preferably about 1.05 to about 1.8. [0077] Good tortuosity is an additional attribute of some embodiments. A devious or tortuous flow path with multiple interruptions and fine pores may act as a filter against penetration of invading solids. Tortuosity of the flow path can be helpful to prevent penetration by loose particles from an electrode or to minimize growth of dendrites through a separator that might cause electrical shorts. This characteristic cannot be quantified, except by long-term use, but it can be observed qualitatively by viewing a cross-section of the porosity. [0078] Some embodiments may be generally uniform and symmetric, i.e. the substrate side pores may be substantially similar in size to the central and the air side pores. Pores varying in diameter by a factor of about 5 or less may be sufficiently uniform for the membranes to function in a symmetric manner. [0079] Where additional strength or stiffness may be needed for handling purposes, micro- or nano-particles can be added to the formulation with such particulates residing within the polymer phase. A few such additives include silica aerogel, talc, and clay. [0080] FIG. 3 is a diagram illustration of an embodiment 300 showing a process for continuous manufacturing of reinforced porous material. Embodiment 300 is an example of a general process that may be used to form porous material directly in a reinforced web, such as a nonwoven web, woven web, or perforated film. [0081] A web 302 may be unwound with an unwinding mechanism 304 and moved in the direction of travel 301 . Various reinforcement webs may be used, including woven and nonwoven. In many embodiments, a nonwoven web may be preferred from a cost standpoint. [0082] As the web 302 is being moved in the direction 301 , solution 302 may be applied to the web 302 with an applicator 308 . The applicator 308 may apply a wet solution 306 to form an uncured solution 310 . [0083] In some embodiments, a carrier material may be used to facilitate handling of the web and may provide a bottom surface against which the liquid solution 306 may be supported while in the uncured state. Such carrier material may include treated kraft paper, various polymeric films, metal films, metalized carriers, or other material. Some embodiments may use a carrier material in subsequent manufacturing steps and may include the carrier material with the cured porous material 314 on the take up mechanism 316 . In other embodiments, the carrier material may be stripped from the cured porous material 314 before the take up mechanism 316 . In still other embodiments, a continuous recirculating belt or screen may be used beneath the web 302 during processing. [0084] The embodiment 300 illustrates a manufacturing sequence that may be predominantly horizontal. In other embodiments, a vertical manufacturing process may have a direction of travel in either vertical direction, either up or down. A vertical direction of travel may enable a porous material to evenly form on two sides of a reinforcement web. Such an embodiment may have an applicator system that may apply solution to both sides of a reinforcement web. Horizontal manufacturing processes, such as embodiment 300 , may result in a final product that may be asymmetrical, with the reinforcement web being located off the centerline of the thickness of the material. [0085] The applicator 308 may be any mechanism by which the solution 306 may be applied to the web 302 . In some embodiments, the solution 306 may be continuously cast, sprayed, extruded, or otherwise applied. Some embodiments may use a doctor blade or other mechanism to distribute the solution 306 . [0086] The thickness of the resulting reinforced porous material may be adjusted by controlling the amount of solution 306 that is applied to the web 302 and the speed of the web during application, among other variables. [0087] Some embodiments may includes various additional processes, such as air knives, calendering, rolling, or other processing before, during, or after the solution 306 has formed into a solid porous polymer material. [0088] The uncured solution 310 may be transferred through a tunnel oven 312 or other processes in order to form a cured porous material 314 , which may be taken up with a take up mechanism 316 . [0089] The tunnel oven 312 may have different zones for applying various temperature profiles to the uncured solution 310 in order to form a porous material. In many cases, an initial lower temperature may be used to evaporate a portion of a primary liquid and begin formation of a solid polymer structure. A higher temperature may be used to remove a second liquid and remaining primary liquid. [0090] In some embodiments, the tunnel oven 312 may provide air transfer using heated or cooled air to facilitate curing. [0091] Embodiment 300 is an example of a continuous process for manufacturing a reinforced porous material by forming the porous material by introducing a wet solution directly onto the reinforcement media. Other embodiments may include casting a porous material directly onto a reinforced web in a batch mode, such as casting on non-moving table surface. [0092] FIG. 4 is a diagram illustration of an embodiment 400 showing a dip method for continuous manufacturing of reinforced porous material. [0093] A web 402 is unwound from an unwinding mechanism 404 and passed through a solution 406 in a bath 408 to form a web with uncured solution 410 . The bath 408 may be ultrasonically activated to remove air and promote wetting of the reinforcement by the solution. The web may pass through a curing zone 412 in which may remove a primary and secondary liquid while forming a polymer with a porous structure. The cured material on a web 414 may be taken up in a take up reel 416 . [0094] Embodiment 400 is an example of a continuous process for forming a porous material directly onto a reinforcement web. By controlling the viscosity of the solution 406 and the speed of operation, a controlled thickness of porous material may be formed. In some embodiments, a doctor blade, calendering mechanism, air knives, or other mechanisms may be used to provide additional control over the thickness of the uncured or cured material. [0095] The curing zone 412 may be any type of mechanism by which the uncured material 410 may be cured. Some embodiments may process the material through various heated or cooled zones, apply various rinses, process the material through a pressurized or vacuum environment, or provide some mechanical processing such as calendering, squeezing, or some other process. Each embodiment may have particular processing performed based on the selection of polymer, the formulation of the solution 406 , and the construction of the reinforcing web 402 . [0096] In some embodiments, the reinforcing web 402 may have various treatments applied prior to coming in contact with the solution 406 . For example, a sizing or other liquid material may be applied to the web 402 . One example may be to pretreat the web 402 with a dilute version of the solution 406 or a solution with a different solvent/polymer combination. In some cases, such a pretreatment may cause the reinforcing web 402 to swell or otherwise improve the bonding of the porous material to the web 402 . Other examples may include applying a corona or spray to the web 402 to partially oxidize the surface of the web 402 . Another example may be to apply an electric charge to the web 402 and an opposite charge to the bath 408 . Still another example may be to ionize the surface of the reinforcing web 402 . Such pretreatment processes may be used with any method for manufacturing a reinforced porous film. [0097] Ultrasonic activation of the solution 406 and reinforcing web 402 may enhance bonding and penetration of the solution 406 into the web. [0098] Ultrasonic activation may be used to supplement any type of mechanism by which a pore forming polymer solution may be applied to a reinforcing web. In some embodiments, ultrasonic energy may be introduced to the solution, while in other embodiments, ultrasonic energy may be applied to the reinforcing web before or after the solution is applied. In embodiment 400 , ultrasonic energy may be applied to the bath 408 or to the reinforcing web 402 prior to entering the bath 408 . Some embodiments may introduce ultrasonic energy to the web after the solution is applied by using an ultrasonic horn directed toward the web. [0099] FIG. 5 is a diagram illustration of an embodiment 500 showing a method for laminating reinforced porous film. Embodiment 500 shows a single cured porous film 502 being joined to one side of a reinforced web 506 . [0100] The porous film 502 may be unwound from an unwinding mechanism 504 and brought into contact with a reinforcement web 506 that is unwound from a second unwinding mechanism 508 . The two plies may be joined by the rollers 510 to form a reinforced porous film 512 that may be wound onto a take up reel 514 . [0101] Embodiment 500 is a method and apparatus for laminating a porous film 504 with a reinforcement web 506 . In some embodiments, an applicator 516 may be used to deliver ionic charge, adhesive, heat, or any other material or processing at the nip point of the joining process. [0102] An adhesive may be used to join the two layers. In some embodiments, the adhesive may contain a solvent that may enable a portion of either or both the polymer from the porous material or the reinforcement web to melt or dissolve and fuse with the other layer. In some cases, a polymer mixture may be used in forming the porous material with one of the polymers in the mixture selected to dissolve in an adhesive to facilitate the bonding to the reinforcement web. Another type of adhesive may contain a dissolved polymer that gels between the two layers to join the layers together. Another adhesive may be heat activated and may partially melt to join the layers. [0103] When adhesives are used, some embodiments may apply a coating of adhesive across one or both of the surfaces to be joined. Other embodiments may apply spots of adhesive in various locations or patterns. [0104] The applicator 516 may apply heat to one or more surfaces to be joined. In some embodiments, the heat may enable a portion of one or more of the materials to be joined to melt and fuse with the other. Such heat may be applied in conjunction with an adhesive. [0105] In some embodiments, the porous film 502 and reinforcement web 506 may be joined together by mechanical interlocking. Such interlocking may be created by applying pressure between the rollers 510 . [0106] In some cases, the porous film 502 may be transferred through a portion of the manufacturing process using a carrier film or other material. In such a case, the carrier film may be removed prior to entering the rollers 510 . [0107] FIG. 6 is a diagram illustration of an embodiment 600 showing a laminating method for two-sided lamination of porous film onto a central reinforced web. Embodiment 600 may use similar processing to that of embodiment 500 , with the addition of a second layer of porous film added so that the reinforcing web is in the center of the laminate. [0108] A first porous film 602 may be unwound from an unwinding mechanism 604 , and similarly a second porous film 606 may be unwound from unwinding mechanism 608 . A reinforcement web 610 is unwound from an unwinding mechanism 612 and laminated between the porous film layers 602 and 606 at the rollers 612 to form a laminate 614 that is taken up by a take up reel 616 . [0109] Embodiment 600 may join the layers of porous film and a reinforcement web by any mechanism whatsoever. In some cases, mechanical interlocking may be used, while in other cases, applicators 620 may apply heat and/or adhesives or other bonding agent or processing that may facilitate bonding. [0110] An adhesive may be used to join the various layers. In some embodiments, the adhesive may contain a solvent that may enable a portion of either or both the polymer from the porous material or the reinforcement web to melt or dissolve and fuse with the other layer. In some cases, a polymer mixture may be used in forming the porous material with one of the polymers in the mixture selected to dissolve in an adhesive to facilitate the bonding to the reinforcement web. Another type of adhesive may contain a dissolved polymer that gels between the two layers to join the layers together. Another adhesive may be heat activated and may partially melt to join the layers. [0111] When adhesives are used, some embodiments may apply a coating of adhesive across one or both of the surfaces to be joined. Other embodiments may apply spots of adhesive in various locations or patterns. [0112] The applicator 620 may apply heat to one or more surfaces to be joined. In some embodiments, the heat may enable a portion of one or more of the materials to be joined to melt and fuse with the other. Such heat may be applied in conjunction with an adhesive. [0113] FIG. 7 is a flowchart illustration of an embodiment 700 showing a method for creating a loaded porous material. The loading may be any nonstructural material that may perform various functions. [0114] In some cases, a loading may be passive and perform a function without changing state or engaging in a chemical reaction. In other cases, an active loading may undergo a chemical reaction or otherwise change state. [0115] Loading may be applied using two different application mechanisms. In one mechanism, a loading may be incorporated into the porous material solution and may become bound into the structure of the porous material. In another mechanism, a loading may be applied to the porous material after formation and may be captured within the pores of the porous material. [0116] In some embodiments, a two part loading material may be used. In such an embodiment, a first material may be incorporated into the solution and may be captured within the porous structure. A second part of the loading material may be applied to the formed porous material and the second part may interact with the first part to create the loading. In some cases, the second part may react with the first part or otherwise cause the first part to undergo a chemical transformation. [0117] The illustration of FIG. 7 is a similar process as FIG. 2 , with the addition of loading material prior to and/or after porous material formation. [0118] The solution is formed in block 202 as described above. [0119] Loading material may be added to the solution in block 702 . The loading material may be dissolved in the solution of block 202 or may be a particulate that may be suspended in the solution. [0120] The solution may be applied to a carrier in block 204 , and enough of the primary solution may be removed in block 206 to begin gelation. The secondary liquid may be removed in block 208 . [0121] Loading material may be added in block 704 which may be after the porous material is formed. In such a case, the loading material may be infused within the porous structure in several manners. In some cases, the loading material may be dissolved in a solution which may permeate the porous material. The solution may be dried, leaving a residue of loading material. [0122] In some cases, a particulate loading material may be infused into the porous structure as a dry material or with a liquid carrier. [0123] In some embodiments, other mechanisms for depositing a loading material may include vacuum deposition mechanisms, surface treatments, or other mechanisms. In some embodiments, the loading material may be applied through the porous structure, while in other cases, the loading material may be applied to the outer surface of the porous structure. [0124] The reinforced porous material may be used in various construction applications. For example, the porous material may be used as a barrier in an exterior wall, roof, or floor. The barrier may be applied underneath siding, stucco, or roofing materials and be used as an air permeable yet watertight barrier. In some cases, insect repellant or anti-microbial loadings may be applied to the barrier to prevent infestation from insects or various microbes. [0125] In some cases, the porous material may be applied between a building and foundation such as underneath a concrete slab, in a crawlspace, or other applications. [0126] The porous material may be used as a vapor barrier in various insulating mechanisms. For example, the porous material may be used as a vapor barrier in fiberglass or other insulation batting. In some cases, the porous material may be applied in conjunction with sprayed or other in situ formed insulating systems. [0127] Reinforced porous material may be used in many interior applications. For example, reinforced porous material may be used as a facing material for wallboard, both for common interior walls and for high humidity applications such as bathrooms and kitchens. [0128] Underlayment applications for the porous material may include underlayment for flooring systems, including carpet and hardwood floors, and may be applied above or below various decking systems in different applications. [0129] In some embodiments, the reinforced porous material may be used as wallpaper, a carrier for wallpaper, or may be applied to a wall prior to applying wallpaper. [0130] FIG. 8 is a diagram illustration of an embodiment 800 showing a cross-section of insulation batting with a vapor barrier. Embodiment 800 is a simplified diagram that may illustrate the basic components of the embodiment. FIG. 8 is not to scale. [0131] Embodiment 800 is a cross sectional illustration of an insulation batting material. A bat of fiberglass insulation 802 is joined to a laminate of a porous film vapor barrier 806 and kraft paper 804 . Embodiment 800 may be used like a conventional batting insulation material with a vapor barrier. Many embodiments are sized to fit between studs in walls of stick framed buildings or between joists in ceilings or floors. [0132] Some embodiments may use different types of insulating material, such as rock wool or other bat-type insulation materials. In many cases, the batting insulation material may be flexible, while in some cases, the insulation material may be rigid. [0133] The porous film vapor barrier 806 may be a microporous material as described above manufactured with a polymer, such as PVDF. The porous film vapor barrier 806 may or may not be created as a laminate with the kraft paper 804 . In some embodiments, the porous film vapor barrier 806 may have a woven or non-woven reinforcement. [0134] The porous film vapor barrier 806 is illustrated as being between the kraft paper 804 and the insulating batting 802 . In other embodiments, the kraft paper 804 may be between the porous film vapor barrier 806 and the insulation batting 802 . [0135] The insulation batting 802 may be adhered to the porous film vapor barrier 806 by adhesive. [0136] Embodiment 800 is an example of a vapor barrier that may allow air exchange through the surface of the vapor barrier, but may prohibit water vapor transmission. [0137] In some embodiments of a bat insulation system, a reinforced microporous polymer membrane may be used instead of a laminate of kraft paper 804 and porous film vapor barrier 806 . [0138] In some embodiments, the porous film vapor barrier 806 may be impregnated with various materials. For example, the porous film vapor barrier 806 may be treated with an anti-microbial material, an anti-fungal material, an insecticide, or some other material to prevent unwanted mold, fungus, or insects to penetrate a building. [0139] FIG. 9 is a diagram illustration of an embodiment 900 showing an exterior wall cross section. The illustration of FIG. 9 may be a top view of a horizontal cross section through a typical stick-framed residential or commercial building. FIG. 9 is not to scale. [0140] Embodiment 900 is an example of a wall cross section that may be constructed with a vapor barrier that is placed on the exterior side of an insulating barrier. Such a construction may be useful in hot, humid climates where the interior of a building may be colder than the exterior. In such cases, a building may have air conditioning or other refrigeration. [0141] Embodiment 900 shows an exterior surface 902 at the top of the illustration and an interior surface 910 at the bottom. Studs 908 and 910 are illustrated in cross section. [0142] In a typical stick-framed residential contruction, the studs 908 and 910 may be constructed with exterior sheathing 912 and raised into position. After positioning the wall, insulation 918 may be applied and the interior surface may be finished with drywall 906 or some other interior surface treatment such as plaster and lath or other construction. [0143] In some embodiments, the exterior walls of a building may be assembled and installed prior to applying a porous film vapor barrier 914 . After the porous film vapor barrier 914 is applied, an external siding system 916 may be applied over the porous film vapor barrier 914 . [0144] FIG. 10 is a diagram illustration of an embodiment 1000 showing an exterior wall cross section. The illustration of FIG. 10 may be a top view of a horizontal cross section through a typical stick-framed residential or commercial building. FIG. 10 is not to scale. [0145] Embodiment 1000 is an example of a wall cross section that may be constructed with a vapor barrier that is placed on the interior side of an insulating barrier. Such a construction may be useful in cold climates where the interior of a building may be predominately warmer than the exterior. [0146] Embodiment 1000 is similar to embodiment 900 with the exception that the porous film vapor barrier 1012 is located on the interior side of the insulation 1018 . In embodiment 900 , the porous film vapor barrier 914 was located on the exterior side of the insulation 918 . [0147] Embodiment 1000 illustrates an interior surface 1002 at the bottom of the illustration and an exterior surface 1004 at the top. Along the interior surface 1002 may be drywall 1006 or some other interior finish. [0148] The porous film vapor barrier 1012 may be located external to the drywall 1006 , but on the interior side of the insulation 1018 . The studs 1008 and 1010 may be the vertical structural support of a wall, and may serve to separate the exterior surface and interior surface in order to place insulation 1018 . [0149] On the exterior surface of the studs 1008 and 1010 is exterior sheathing 1014 and an exterior siding system 1016 . [0150] In either embodiment 900 or 1000 , the insulation 1018 may be any type of insulation, such as fiber glass bat, rock wool, blown in fibrous insulation, form in place insulation, or any other insulation system. [0151] In either embodiment 900 or 1000 , the interior finish material may be drywall as illustrated or some other interior finish system. Examples of other interior finish system may include paneling, plaster, tile, wallboard, tile, or any interior finish. [0152] In either embodiment 900 or 1000 , the exterior siding system may be any type of exterior siding. Examples include lap siding, aluminum or vinyl siding, shake or shingle siding, brick siding, tile siding, stucco, plaster, or another type of exterior siding. [0153] The construction of embodiments 900 and 1000 are illustrated as side walls of a typical framed residence. Other similar embodiments may be employed for roofing applications that may be flat or pitched roofing systems. In many pitched roofing systems, an airflow space may be provided between the insulation and exterior sheathing. [0154] Embodiments 900 and 1000 illustrate an exterior wall of a building. The same or similar construction may be used for any exterior barrier, which may include walls, floors, or roofs. The construction may be made up of several layers that may be assembled or installed in different sequences to achieve the construction as shown. In some embodiments, additional materials or layers may be included in the assembly. [0155] FIG. 11 is a diagram illustration of an embodiment 1100 showing a roofing system cross section. Embodiment 1100 may be a simplified example of a membrane style flat roofing system. FIG. 11 is not to scale. [0156] Embodiment 1100 illustrates the interior surface 1102 on the bottom of the illustration and an exterior surface 1104 on the top. A joist 1106 is illustrated as running parallel to the illustration and supporting a decking system 1108 . [0157] Above the decking system 1108 , a porous film vapor barrier 1110 may be installed. [0158] Insulation 1112 may be installed over the porous film vapor barrier 1110 and a roofing membrane 1114 may be installed over the insulation 1112 . [0159] FIG. 12 is a diagram illustration of an embodiment 1200 showing a cross section of a crawlspace. Embodiment 1200 is a simplified example of a typical construction that includes a crawlspace below the lowest floor of a building. In many embodiments, a crawlspace may be unheated. [0160] Embodiment 1200 illustrates an exterior wall 1202 and a foundation 1204 that may rest on a footer 1206 . The foundation 1204 and footer 1206 may be buried in earth 1208 on the outside of the building and earth 1210 underneath the building. [0161] The crawlspace 1212 may be a space above the earth 1210 and joists 1214 that support a floor. [0162] A porous film vapor barrier 1218 may be placed above the joists 1214 and below a flooring system 1216 . The porous film vapor barrier 1218 may prevent vapor from infiltrating the interior of the building from the exposed earth 1210 in the crawlspace 1212 . [0163] An alternative placement for a porous film vapor barrier 1220 may be below the lower surface of the joists 1214 . [0164] In the embodiments 800 , 900 , 1000 , 1100 , and 1200 , the porous film vapor barrier may be infiltrated or coated with various anti-microbial agents that may inhibit mold, mildew, bacteria, or other unwanted organisms into a building. In some embodiments, the porous film vapor barrier may be infiltrated or coated with an insecticide or other agent that may kill or deter insects or other pests from entering a building. Such materials may be added to the porous film by dipping or spraying the film after manufacturing the film. In some embodiments, the materials may be added to the porous film by incorporating the materials in the solution prior to forming the porous film. [0165] In embodiments with anti-pathogen properties such as anti-microbial properties described above, additives such as iodine, silver, silver oxide, silver nitrate, zinc, zinc sterate, copper glutamate, copper chloride, or other materials may be added to the microporous film. Such materials may be added to the polymer solution prior to forming the microporous film or by applying the materials after formation. Another material that may be added during formation may be an ultraviolet barrier may be created by adding zinc oxide to the microporous film. [0166] In the embodiments 800 , 900 , 1000 , 1100 , and 1200 , the porous film vapor barrier may be constructed with any type of reinforcement material. [0167] The foregoing description of the subject matter has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the subject matter to the precise form disclosed, and other modifications and variations may be possible in light of the above teachings. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments except insofar as limited by the prior art.

A barrier membrane for use in building construction may be manufactured by forming a polymeric film coating on release paper or film; or on nonwoven textiles, paper, fiberglass, or other structural substrate to improve tensile strength. Alternatively, the film may be fully or partially formed and then bonded to a structural substrate. A porous film coating or laminate may be formed using PVDF, PVC, and various polyolefins. A typical membrane may be less than 100 mil thick and greater than 50% porous, and may have a hydrostatic head while retaining gas permeability. Some embodiments may contain active ingredients to combat bacterial or fungal growth, repel insects, or absorb environmental pathogens. The active ingredients may be applied after the porous film is manufactured or may be incorporated during the film manufacturing process.

You are an expert at summarizing long articles. Proceed to summarize the following text: STATEMENT OF GOVERNMENT INTEREST [0001] This invention was developed under Contract No. N00174-00-C-0021 issued by the Defense Logistics Agency, SBIR Topic N99-114. The United States Government may have rights in this invention. TECHNICAL FIELD [0002] This invention relates generally to the field of chemical drills, and, more particularly, to an improved chemical drill that is capable of drilling holes in, or otherwise removing material from, a wide variety of target materials, such as ferrous and non-ferrous alloys, concrete, various ceramic materials, and the like. BACKGROUND OF INVENTION [0003] In civilian applications, high-speed chemical cutting is used in cutting, scarfing and lancing of oxidation-resistant materials. In steel mills, cutting is used to scarf large ingots, slabs and billets. Chemical lancing permits rapid and effective piercing of many materials that are difficult to pierce with standard hydrocarbon/oxygen flame technology. These materials include, for example, various irons and steels, firebrick, cinder block, aluminum billets, sand and metal incrustations in castings, and the like. Typical lancing applications include: (a) removal of blast furnace bosh plates, (b) removal of large iron masses (i.e., “salamanders”) that are deposited at the base of blast furnace, (c) cleaning of furnace linings, (d) furnace tapping to remove slag, (e) cleaning of soaking pits, (f) removal of ladle skulls, and (g) piercing holes in reinforced concrete walls and floors. [0004] Underwater cutting and/or welding techniques are used in the repair of offshore platforms. These techniques have also been useful during the installation of new off-shore structures and undersea pipelines, the installation of hot taps, the repair of dock and harbor facilities, the modification of and addition to underwater structures, the repair of nuclear facilities, and still other applications. Permanent and temporary repairs to holes in ship- and barge-hulls have been performed. Hulls and pontoons of semi-submersible drill ships have also been repaired. Still other applications have included cutting of ship stems from castings, cutting reinforced concrete under water, underwater ship husbandry operations, salvage and rescue missions, and the like. [0005] The common process used in industry for such cutting is the so-called “lance technology”. This process represents one of the oldest commercial uses of oxygen for piercing and cutting holes in hard materials. These materials include practically all ferrous metals and many other materials, such as concrete, slag, rock, and the like. Initially, such lances were simply an elongated length of hollow iron pipe connected at one end to a source of oxygen through an intermediate flow regulator. [0006] Conventional lance technology employs the use of a steel pipe containing steel wires or rods. Oxygen is blown through the pipe at high pressure. The pipe, and the rods therewithin, are ignited at one end, and oxygen-rich gas is blown through the pipe. This oxidizes the pipe and the rods, and produces a hot flame. The discharge end of the lance is held in the cut or hole so that the cutting flame is presented at the distal end of the lance. The flame heats and burns the end of the pipe so that, as the operation proceeds, the pipe is consumed and must be periodically replaced with a new length of pipe. Only a small portion of the oxygen consumed is required by oxidation of the lance itself, but the heat of the burning lance assists the cutting. Once started, the reaction is very vigorous, and usually produces a lot of “splatter” of semi-solid highly-viscous lava-like material outwardly from the discharge end of the lance. If this material accumulates at the bottom of the hole or cut, it creates an obstacle to continued drilling or cutting. [0007] Over the last ten years, there has been renewed interest in oxygen lance techniques, resulting in many improvements in the basic oxygen lance structure. Some of these improvements include the provision of one or more elongated rods within the lance, the mounting of the various component parts relative to each other, specialized configurations for the outer casting and inner rods, and cooperation between the inner rods when received within the outer casing. However, there are not believed to have been any changes in the basic chemistry of the lance process and technology. Iron-containing wires and tubes, and oxygen, remain the basic building blocks of known applications. [0008] Other details of prior art lances, devices and methods are shown and described in U.S. Pat. Nos. 4,928,757, 4,889,187, 3,570,419, 5,320,174, 3,602,620, 5,575,331, 5,580,515, 3,725,156, 3,751,625, 4,477,060, 4,182,947 and 4,050,680, the aggregate disclosures of which are hereby incorporated by reference. DISCLOSURE OF THE INVENTION [0009] The invention relates to an improved chemical drill for converting the reaction products resulting from the cutting, drilling or piercing operation, to gaseous or very volatile products that can be easily directed away from the bottom of the hole or cut so as to not interfere with ongoing and continuous drilling or cutting operations. In effect, the hole or cut is self-cleaning. This results in the reduction or elimination of heat and mass transfer cutting resistances that were commonly present in the prior art, and, consequently, increases the possible cutting rate by a factor to about two to a factor of about four. The proposed drill particularly effective where deep holes or plunging cuts are necessary. The improved drill makes it possible to cut targets, such as concrete, reinforced concrete, ceramic plates, highly alloyed steel, aluminum blocks, laminated structure, granite and the like, that in the past presented major problems. [0010] With parenthetical reference to the preferred embodiments disclosed herein, merely for purposes of illustration and not by way of limitation, the present invention provides an improved chemical drill ( 20 ) for removing portions (e.g., by drilling) of a target material ( 30 ). Examples of such target materials include, but are not limited to: ferrous alloys, alloys having an element selected from the group consisting of aluminum, copper, magnesium, titanium, a transition metal (i.e., titanium, niobium, zirconium, hafnium, vanadium and tantalum), tungsten, nickel, cobalt and chromium, concrete, reinforced concrete, aluminum oxide, silicon oxide, calcium oxide, brick, and ceramic materials selected from the group consisting of alumina, silica, zirconia, magnesia, silicon carbide and silicon nitride. [0011] The improved drill broadly includes: an elongated tube ( 21 ) formed of a fuel-supplying material; a source ( 24 ) of oxidizer; a conduit ( 26 ) for establishing a controllable flow of oxidizer from said source through said tube; and a sleeve ( 28 ) formed of a material containing chlorine and/or fluorine mounted on said tube, such that, when said drill is ignited and used to remove portions of a target material, the chlorine and/or fluorine in said sleeve material will react chemically with the target material to produce volatile gaseous reaction products, which may be readily directed out of the hole or cut and thereby removing substantial resistance to heat and mass transfer within the hole or cut. [0012] In the preferred embodiment, the sleeve is mounted on the outer surface of said tube. A plurality of wires or rods may be arranged in the tube. The sleeve material may contain polyvinyl chlorine, polytetrafluoroethylene, chlorinated polyvinyl chlorine and/or some other material(s) that will contribute chlorine and/or fluorine to the ongoing reaction. The tube may contain iron. [0013] Accordingly, the general object ofthe invention is to provide an improved chemical drill or cutter. [0014] Another object is to provide a chemical drill or cutter which increases the rate-of-removal of the target material by a factor of from about two to about four times that of known chemical drills. [0015] Another object is to provide an improved high-speed chemical drill that is capable of use with a variety of target materials. [0016] These and other objects and advantages will become apparent from the foregoing and ongoing written specification, the drawings, and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS [0017] [0017]FIG. 1 is a sketch, partly in section and partly in elevation, of the improved chemical drill, this view showing the plastic sleeve as surrounding the steel pipe lance. [0018] [0018]FIG. 2 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nFe+(10−n)C 2 Cl 4 +20O 2 ], for the reactions of Example 1. [0019] [0019]FIG. 3 is a plot of equilibrium concentrations (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nFe+(10−n)C 2 F 4 +20O 2 ], for the reactions of Example 1. [0020] [0020]FIG. 4 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nTi+(10−n)C 2 Cl 14 +20O 2 ] for the reactions of Example 2. [0021] [0021]FIG. 5 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nTi+(10−n)C2F4+20O 2 ], for the reactions of Example 2. [0022] [0022]FIG. 6 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and sleeve combinations of [nAl+(10−n)C 2 Cl 4 +20O 2 ], for the reactions of Example 3. [0023] [0023]FIG. 7 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nAl+(10−n)C 2 F 4 +20O 2 ], for the reactions of Example 3. [0024] [0024]FIG. 8 is a plot of equilibrium concentration (ordinate) vs. temperature (abscissa) for [concrete(3.46CaO+11.1 SiO 2 )+50O 2 +14.56Fe], for the reactions of Example 5. [0025] [0025]FIG. 9 is a plot of equilibrium concentration (ordinate) vs. temperature (abscissa) for [concrete(3.46CaO+11.1 SiO 2 )+20.01C 2 F 4 +46.3O 2 +14.56Fe], for the reactions shown in Example 5. [0026] [0026]FIG. 10 is a plot of equilibrium concentration (ordinate) vs. temperature (abscissa) for [concrete(3.46CaO+11.1SiO 2 )+20.01C 2 Cl 4 +47.302+14.56Fe], for the reactions of Example 5. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0027] At the outset, it should be clearly understood that like reference numerals are intended to identify the same structural elements, portions or surfaces consistently throughout the several drawing figures, as such elements, portions or surfaces may be further described or explained by the entire written specification, of which this detailed description is an integral part. Unless otherwise indicated, the drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, degree, etc.) together with the specification, and are to be considered a portion ofthe entire written description of this invention. As used in the following description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof(e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate. [0028] Thermal piercing of concrete or reinforced concrete or highly alloyed steel plates is normally a difficult task. The molten lava of the target material at the tip of the lance provides substantial heat and mass transfer resistance to ongoing drilling or cutting operations. A typical product of thermal penetration of a concrete block by a thermal lance is lava composed of oxides of silicon, calcium, aluminum and iron. The melting point of this mixture, depending on the composition, is between about 1600-1800° C. The present invention is based on the principle of producing gaseous chemical reaction products, products or components that readily sublimate at low temperatures, or products or components with low boiling points, rather than highly-viscous lava, and directing these gaseous materials out of the hole or cut so as to remove their mass therefrom and to allow continuous cutting or drilling without diminution of penetration efficiency due to accumulations of lava-like materials in the hole or cut. [0029] Several inorganic oxides react with chlorine or fluorine in the presence of carbon to form volatile chlorides or fluorides. These reactions, sometimes also called “carbochlorination” or “carbofluorination” reactions, occur with reasonable reaction rates at 800-1000° C. At temperatures above 1600° C., which are typical for a cutting torch, these reactions are very fast. [0030] There are different sources of carbon, chlorine or fluorine that can be utilized to carry out the reaction. A source of carbon could be a carbon jacket surrounding the metallic jacket of the regular lance, a fine powder of carbon that is blown in the cutting spot, or a certain group of organic compounds that decompose at cutting-torch temperatures to elemental carbon. Lower hydrocarbons can be easily pyrolyzed at high temperatures. Lower chlorinated hydrocarbons, such as ethylene trichloride, elemental chlorine, PVC, perchlorinated PVC, or the like, can be used as a source of chlorine. Lower fluorinated hydrocarbons, such as polytetrafluoroethylene (i.e., Teflon®) or other polymers rich on fluorine, can be used as a source of fluorine. It is possible to inject these lower chlorinated or fluorinated hydrocarbons into the torch flame in a gaseous form. Polymers containing chlorine and/or fluorine can be part of the cutting lance body. For example, the body of the cutting lance can be inserted in a Teflon® tube. [0031] After thermal ignition ofthe modified lance halogenated products are transported to the reaction spot and one or more of the following reactions may take place: [0032] For Concrete: SiO 2 +2C+2Cl 2 →SiCl 4 ↑+2CO↑  (1) SiO 2 +2C+4HCl→SiCl 4 ↑+2CO↑+2H 2 ↑  (2) SiO 2 +2C+4HF→SiF 4 ↑+2CO↑+2H 2 ↑  (3) nSiO 2 +[—CF 2 —CF 2 —] n →nSiF 4 ↑+2nCO↑  (4) CaO+C+Cl 2 →CaCl 2 ↑+CO↑  (5) CaO+C+2HCl→CaCl 2 ↑+CO↑+H 2 ↑  (6) 2CaO +[—CF 2 —CF 2 —] n →2CaF 2 ↑+2CO↑  (7) [0033] For Granite: [0034] Any of chemical reactions (1)-(7) and one or more of the following additional reactions: Al 2 O 3 +3C+3Cl 2 →2AlCl 3 ↑+3CO↑  (8) Al 2 O 3 +3C+6HCl→2AlCl 3 ↑+3CO↑+3H 2 ↑  (9) 3[—CF 2 —CF 2 —] n +2nAl 2 O 3 →4nAlF 3 ↑+6nCO↑  (10) [0035] For Iron: 2FeO+2C+3Cl 2 →FeCl 3 ↑+2CO↑  (11) Fe 2 O 3 +3C+3Cl 2 →2FeCl 3 ↑+3CO↑  (12) 4nFeO+[—CF 2 —CF 2 —]→4nFeF 3 ↑+4nCO↑+2nC↑  (13) 2nFe 2 O 3 +[—CF 2 —CF 2 —] n →4nFeF 3 ↑+6nCO↑  (14) [0036] For Ni- and Cr-Alloyed steel: NiO+C+Cl 2 →NiCl 2 ↑+CO↑  (15) 2CrO 3 +6C+3Cl 2 →2CrCl 3 ↑+CO↑  (16) 2NiO+[—CF 2 —CF 2 —] n →2NiF 2 ↑+2CO↑  (17) 4nCrO 3 +3[—CF 2 —CF 2 —] n →4nCrF 6 ↑+12CO↑  (18) [0037] In the foregoing reactions, the symbol “↑” indicates that the indicated element or compound is substantially gaseous at the reaction temperature. Persons skilled in this art will appreciate that CaCl 2 , CaF 2 , FeCl 3 , NiCl 2 , CrCl 3 , NiF 2 and CrF 6 may only be partially gaseous at the normal reaction temperatures. Improving of Cutting Properties of a Regular Iron-Oxygen Lance [0038] Referring now to the drawings, and, more particularly, to FIG. 1 thereof, an improved lance, generally indicated at 20 , is shown as broadly including a horizontally-elongated iron or steel tube 21 having inner and outer cylindrical surfaces 22 , 23 , respectively. This tube may be about 3 feet long, have an inside diameter of about ⅜″, and a radial wall thickness of about {fraction (1/16)}″. The rightward or proximal end of the tube is connected to a source 24 of oxygen or oxygen-rich gas through an intermediate flow regulator 25 . Thus, oxidizer may flow form source 24 to the tube via the flow regulator and a conduit, portions of which are indicated at 26 . The tube is formed of a fuel material, such as iron or a ferrous alloy. A sleeve, generally indicated at 28 , surrounds the tube. This sleeve is formed of a material that contains chlorine (e.g., polyvinyl chloride, chlorinated polyvinyl chloride, etc.) and/or fluorine (e.g., polytetrafluoroethylene). A plurality of rods or wires, severally indicated at 29 , are disposed within the tube to contribute additional reactant(s). [0039] There are different sources of carbon for carbochlorination and carbofluorination reactions. One source of carbon could be a carbonjacket surrounding a regular commercial lance. The invention utilized a carbon tube with very thin walls, as well as layer of a graphoil surrounding the lance. The carbon serves as a focusing element. With a regular lance, the flame dissipates a lot of energy. With the carbon external shield the energy dissipation is lower. The explanation of this fact is straightforward. In a regular operation, the surrounding iron tube melts or is burned in synchronization with the flame propagation. However, with the carbon jacket, no melting occurs since the melting/sublimation point of carbon is around 4,000° C. The carbon jacket can burn in oxygen. The burning process is apparently a little bit slower than the burning of iron material. Consequently, the unreacted carbon tube serves as an opening to the hot flame. Details of the experiment can be found in Examples 4-6. [0040] The performance of the invention was tested on steel plates of thicknesses of 0.26″ and 1.3″, respectively, and on a concrete plate 4.2″ thick. For the thin steel plate, there is no appreciable difference. This was not surprising since the heat-affected zone does not play an important role. However, with the thick plate, the difference is almost 100%. [0041] The experiment with concrete slab revealed that there is no difference in rate of penetration of regular or focused lance. In a focused lance, the heat flux is much higher than in the regular lance. Nevertheless, the rate of penetration is almost the same. This is an experimental proof that the rate of cutting or drilling in concrete blocks is inversely related to the amount of lave-like material accumulating in the hole or cut. In other words, in a conventional lance, the rate of cutting slows as lava-like material accumulates in the hole or cut, and interferes with the continued cutting or drilling. Faster removal of such lava-like material will result in the improved performance of the torch. There appear to be several possibilities of increasing the rate of concrete blow-off: (a) higher linear velocity of the gas at the mouth of the torch, (b) lowering viscosity of the concrete melt by appropriate additions to the gas (e.g., fluorides, as the resulting eutectic mixture has a lower melting point and a lower viscosity at the cutting temperature can be expected), and (c) converting the liquid concrete to gaseous components (carbochlorination). [0042] Supplying gaseous chlorine along with gaseous oxygen to the hot combustion zone will guarantee the presence of chlorine at the reaction site. The resulting volatile chlorides of iron, silicon, aluminum and calcium will evaporate from the hot spot, and therefore the heat and mass transfer will be much higher. In addition, rebar (e.g., ferrous reinforcing rod) in the concrete structure will not represent an obstacle, but rather increase the rate of penetration. EXAMPLE 1 [0043] Combustion in an “Iron-Chlorinated/Fluorinated Polymer-Oxygen” System [0044] The combustion system consists of a steel tube, a chlorinated/fluorinated polymer sleeve, and an excess of oxygen. The adiabatic temperature, evaluated from thermodynamic calculations, indicates that the combustion temperature in systems with chlorine or fluorine is always higher than in systems with oxygen alone. A typical difference amounts to 250-500° C. [0045] The dependence of adiabatic temperature on the composition of the mixture is given in FIG. 2. FIG. 2 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nFe+(10−n)C 2 Cl 4 +20O 2 ], for the reactions of Example 1. This figure shows that for concentrations of less than about 6 moles, the reaction products Fe+FeCl+FeCl 2 +FeCl 3 +FeO+Fe 2 Cl 14 are substantially gaseous, and that the reaction temperatures are between about 2250-2650° K. [0046] The composition of the combustion products is reported in FIG. 3. FIG. 3 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nFe+(10−n)C 2 F 4 +20O 2 ], for the reactions of Example 1. This plot shows that reaction products Fe+FEO are gaseous at concentrations in excess of n=4 moles. EXAMPLE 2 [0047] Combustion in an “Titanium-Chlorinated/Fluorinated Polymer-Oxygen” System [0048] The combustion system consists of a titanium tube, a chlorinated/fluorinated polymer sleeve, and an excess of oxygen. The adiabatic temperature, evaluated from thermodynamic calculations, indicates that the combustion temperature in systems with chlorine or fluorine is usually lower than in systems with oxygen alone. For example, for a system consisting of 5 moles of titanium and 25 moles of oxygen the combustion temperature is 3,100° K; for a system with 5 moles of titanium, 20 moles of oxygen and 5 moles of —C 2 F 2 — the temperature is 2,500° K and for system of 5 moles of titanium, 20 moles of oxygen and 5 moles of —C 2 Cl 2 — the temperature is 2,900° K. [0049] More details are presented in FIGS. 4 and 5. FIG. 4 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nTi+(10−n)C 2 Cl 14 +20O 2 ] for the reactions of Example 2. FIG. 4 shows that reaction products Ti+TiCl+TiCl 2 +TiCl 3 +TiCl 4 +TiO+TiOCl+TiOCl 2 +TiO 2 are gaseous. FIG. 5 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nTi+(10−n)C2F4+20O 2 ], for the reactions of Example 2. FIG. 5 shows that reaction products Ti+TiO+TiOF+TiO 2 are gaseous. EXAMPLE 3 [0050] Combustion in an “Aluminum-Chlorinated/Fluorinated Polymer-Oxygen” System [0051] The combustion system consists of an aluminum tube, a chlorinated/fluorinated polymer sleeve, and excess of oxygen. The adiabatic temperature, evaluated from thermodynamic calculations, indicates that the combustion temperature in systems with chlorine or fluorine is close to that in systems with oxygen alone. The combustion temperature in these systems can be well above 3,000° K. [0052] Additional details are shown in FIGS. 6 and 7. FIG. 6 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and sleeve combinations of [nAl+(10−n)C 2 Cl 4 +20O 2 ], for the reactions of Example 3. This plot shows that Al+AlCl+AlCl 2 +AlCl 3 +AlO+AlOCl+AlOCl 2 +AlO 2 +Al 2 O+Al 2 O 2 +Al 2 O 3 are gaseous. FIG. 7 is a plot of equilibrium concentration (left ordinate) and adiabatic temperature (right ordinate) vs. concentrations (n) (abscissa) of lance-and-sleeve combinations of [nAl+(10−n)C 2 F 4 +20O 2 ], for the reactions of Example 3. This plot shows that Al+AlF+AlF 2 +AlF 3 +AlO+AlOF+AlOF 2 +AlO 2 +Al 2 O+Al 2 O 2 +Al 2 O 3 are gaseous. EXAMPLE 4 [0053] External Carbon Tube as a Focusing Element [0054] A standard lance “iron-oxygen” is represented by an iron pipe with an array of iron wires inside. Oxygen gas is blown through this arrangement. This assembly has been inserted in a carbon tube. Carbon reacts with oxygen and liberates large amount of heat. Adiabatic temperature of carbon combustion in pure oxygen is above 4000° C. Carbon is also focusing the flame and less heat is dissipated to the environment. [0055] An iron plate (thickness=1.3″, length=6.0″) was cut by a regular commercial lance in 76 seconds; the cutting rate was 0.20 cm/sec. The same plate was cut by a modified lance with external carbon shield in 43 seconds. The cutting rate increased to 0.38 cm/sec. As an external carbon shield a layer of graphoil material was used. EXAMPLE 5 [0056] Carbofluorination Piercing of Concrete Slabs [0057] This example illustrates that using fluorine containing materials improves the efficiency, cutting speed, consumption of oxygen and consumption of the cutting lance essentially. [0058] Experimental data for the cutting experiment are reported in Table 1, and in FIGS. 8-10. FIG. 8 is a plot of equilibrium concentration (ordinate) vs. temperature (abscissa) for [concrete(3.46CaO+11.1 SiO 2 )+50O 2 +14.56Fe], for the reactions of Example 5. This plot shows that Ca+CaO+Fe+FeO+SiO+SiO 2 are gaseous. FIG. 9 is a plot of equilibrium concentration (ordinate) vs. temperature (abscissa) for [concrete(3.46CaO+11.1SiO 2 )+20.01C 2 F 4 +46.3O 2 +14.56Fe], for the reactions shown in Example 5. This plot shows that CaF+CaF 2 +Fe+FeO+SiF 2 +SiF 3 +SiF 4 +SiO are gaseous. FIG. 10 is a plot of equilibrium concentration (ordinate) vs. temperature (abscissa) for [concrete(3.46CaO+11.1SiO 2 )+20.01C 2 Cl 4 +47.3O 2 +14.56Fe], for the reactions of Example 5. This plot shows that CaCl 2 +FeCl 2 +FeCl 3 +Fe 2 Cl 6 +SiO+SiO 2 are gaseous. EXAMPLE 6 [0059] Carbofluorination Piercing of Concrete Slabs [0060] This example provides additional experimental observations on superiority of using fluorinated materials against concrete materials. [0061] Experimental data for the cutting experiment are reported in the Table 2. Concrete block (thickness=15.0 cm). Note: Hole piercing was completed when penetration was achieved. Number of lances burned is indicated in second column. EXAMPLE 7 [0062] Carbofluorination Piercing of Concrete Slabs [0063] This example compares modified lances against concrete walls of different thickness. Length Burned Type of Lance Time(s) (inches) 1st Concrete Block (thickness = 6.0 cm) BROCO 51.81 24.0 64.18 28.0 BROCO with Fe tubing 32.81 14.0 35.44 15.0 FEP 45.46 19.5 FEP with Fe tubing 25.13 8.5 PTFE 30.63 14.0 PTFE with Fe tubing 26.79 10.0 TFE extruded No penetration — PFA 15.10 9.0 KYNAR 48.71 18.5 2nd Concrete Block (thickness = 7.5 cm) KYNAR No penetration 25.0 PFA 37.87 15.0 PTFE 50.35 20.0 PTFE with Fe tubing 31.02 12.5 FEP 37.84 16.0 FEP with Fe tubing 30.01 11.0 BROCO No penetration 27.5 BROCO with Fe tubing 43.45 19.5 3rd Concrete Block (thickeness = 9.8 cm) BROCO No penetration 28.5 No penetration 28.5 BROCO with Fe tubing No penetration 27.0 PTFE No penetration 26.0 No penetration 29.5 FEP with Fe tubing 46.85 18.0 PEP 67.70 26.0 60.99 25.0 FEP with Fe tubing 38.36 15.0 PFA 43.66 18.0 42.57 16.5 [0064] When BROCO is modified with FEP tubing, the pierce rate was increased by more than 90% (i.e., from 0.073 to 0.139 cm/sec). When BROCO was modified with FEP tubing, the lance burning rate decreased by more than 10% (i.e., from 1.373 to 1.207 cm/sec). When BROCO was modified with FEP tubing, the oxygen consumption needed for piercing a 15 cm deep hole decreased by more than 45% (i.e., from 275.28 to 144.67 liters). EXAMPLE 8 [0065] Carbofluorination Piercing of Granite Slabs [0066] Piercing of 0.75 inch thick granite slab by the FEP lance took only 7 sec. of cutting time. Obviously, since granite components are basically silica and alumina both were converted to gaseous products in the course of penetration. Granite objects are ideal targets for a very fast piercing by a modified lance EXAMPLE 9 [0067] Graphoil Wrap/Aluminum Wires [0068] Improved cutting/piercing of cutting of iron slabs by using graphoil wrap as focusing element and using aluminum wires to increase the penetration efficiency [0069] Graphoil layer on the surface of the lance is capable of sharp focusing of the exit hot flame and substantially contributes toward a better performance of the lance. In addition a combination of aluminum and iron wires along with graphoil wrap provides additional improvement of the cutting efficiency. [0070] The following lances were used in this experiment: (1) BROCO lance (⅜″, linear density=3.933 g/cm); (2) BROCO lance (⅜″) covered by graphoil (thickness=0.015″, width=1.5″, linear density=0.156 g/cm); (3) aluminum lance (⅜″) made from Al tubing (OD=⅜″; wall thickness=0.035″, 6061, linear density=0.648 g/cm) and 7 BROCO Fe wires covered by graphoil (thickness−0.010″) fixed with epoxy glue. [0071] Experimental data for the cutting experiment are reported in Table 3. EXAMPLE 10 [0072] Carbochlorination Piercing of Concrete Slabs [0073] Experimental conditions: oxygen outlet pressure=80 psi; flow=80 liters per minute, experiments with concrete block (thickness=15 cm). [0074] The experiment used three types of lances: (1) BROCO lance (⅜″) covered by a fluorinated ethylene propylene (FEP) resin−ID=⅜″, wall thickness={fraction (1/16)}″, linear density=1.2249 g/cm) and 10″ long Fe tubing (OD=0.625″, linear density=3.37 g/cm); (2) BROCO lance (⅜″) covered by a chlorinated Teflon® resin-ID=⅜″, wall thickness={fraction (1/16)}″, linear density=1.2234 g/cm, Laird Plastics, Inc.) and 10″ long Fe tubing (OD=0.625″, linear density=3.37 g/cm); and (3) BROCO lance (⅜″) covered by foil of chlorinated Teflon® resin−linear density=1.3205 and 1.2885 g/cm, Honeywell. [0075] Experimental data for the cutting experiment are reported in Table 4. [0076] Therefore, while presently-preferred forms ofthe inventive high-speed chemical drill have been shown and described, and several modifications thereof discussed, persons skilled in this art will readily appreciate that various additional changes and modifications may be made without departing from the spirit ofthe invention, as defined ad differentiated by the following claims. TABLE 1 Time Length O 2 Needed Needed to of for the Lance Molar Make a 15 Lance Run (@ Pierce Burning Material Burned ratio Type of cm Hole Burned 80 l/min) Rate Rate Fe C 2 F 4 Lance: O 2 Lance (sec) (cm) (liters) (cm/sec) (cm/sec) g mol g mol Mol/mol BROCO 187.38 246.38 249.8 0.080 1.315 969 17.4 — — 1.55 183.60 241.30 244.8 0.082 1.314 949 17.0 — — 1.56 (avg) 185.49 243.84 247.3 0.081 1.315 959 17.2 — — 1.56 BROCO 120.51 129.54 160.7 0.124 1.075 509 9.1 78 0.8 1.38 with FEP 110.20 147.32 146.9 0.136 1.337 579 10.4 89 0.9 1.72 109.79 121.92 145.1 0.138 1.121 480 8.6 74 0.7 1.44 114.67 132.08 152.9 0.131 1.152 519 9.3 80 0.8 1.48 (avg) 113.54 132.72 151.4 0.132 1.169 522 9.3 80 0.8 1.49 BROCO 149.93 187.96 199.9 0.100 1.254 1316 23.6 — — 2.64 with Fe tubing BROCO 76.81 71.12 102.4 0.195 0.926 498 8.9 43 0.4 2.03 with FEP and Fe tubing 81.20 83.82 108.3 0.185 1.032 587 10.5 51 0.5 2.28 73.10 81.28 97.5 0.205 1.112 569 10.2 49 0.5 2.46 (avg) 77.04 78.74 102.7 0.195 1.022 551 9.9 47 0.4 2.25 [0077] [0077] TABLE 2 Time Length O 2 Needed Needed to of for the Lance Molar Make a 15 Lance Run (@ Pierce Burning Material Burned ratio Type of cm Hole Burned 80 l/min) Rate Rate Fe C 2 F 4 Lance: O 2 Lance (sec) (cm) (liters) (cm/sec) (cm/sec) g mol g mol Mol/mol BROCO 214.65 292.10 286.20 0.070 1.361 1149 20.6 — — 1.61 183.60 279.40 244.80 0.082 1.522 1099 19.7 — — 1.80 221.13 273.05 294.84 0.068 1.235 1074 19.2 — — 1.46 (avg) 206.46 281.52 275.28 0.073 1.373 1107 19.8 — — 1.62 BROCO 111.11 129.54 148.10 0.135 1.166 509 9.1 78 0.8 1.50 with FEP tubing 118.13 149.86 157.50 0.127 1.269 589 10.6 90 0.9 1.64 96.30 114.30 128.40 0.156 1.187 450 8.0 69 0.7 1.52 (avg) 108.51 131.23 144.67 0.139 1.207 516 9.2 79 0.8 1.55 BROCO 121.15 134.62 161.53 0.124 1.111 529 9.5 169 1.7 1.55 with two FEP tubings 119.06 144.78 158.75 0.126 1.216 569 10.2 182 1.8 1.69 88.60 93.98 118.13 0.169 1.061 370 6.6 118 1.2 1.48 (avg) 109.60 124.46 146.14 0.140 1.129 489 8.8 156 1.6 1.59 BROCO 104.24 100.33 138.99 0.144 0.962 395 7.1 92 0.9 1.29 with KYNAR tubing 91.84 88.90 122.45 0.163 0.968 350 6.3 81 0.8 1.30 96.28 105.41 128.37 0.156 1.095 415 7.4 96 1.0 1.47 84.76 76.20 113.01 0.177 0.899 300 5.4 70 0.7 1.21 85.12 100.33 113.49 0.176 1.179 395 7.1 92 0.9 1.58 (avg) 92.45 94.23 123.26 0.163 1.021 371 6.6 86 0.9 1.36 BROCO 172.72 158.75 230.29 0.087 0.919 624 11.2 182 1.8 1.26 with PTFE tubing [0078] [0078] TABLE 3 Length O 2 Needed of for the Lance Molar Length Lance Run (@ Cutting Burning Material Burned ratio Type of of Burned 235 l/min) Rate Rate Fe C 2 F 4 Lance: O 2 Lance Cut (cm) (cm) (liters) (cm/sec) (cm/sec) g mol g mol Mol/mol Outlet Pressure = 50 psi; Oxygen Flow = 235 l/min; Steel Plate; Thickness = 2.5 cm BROCO 24.0 35.0 87.3 0.609 0.889 138 2.46 0.358 BROCO + 24.0 25.5 135.2 0.695 0.739 100 1.80 — — 0.298 graphoil BROCO 23.0 32.5 136.9 0.658 0.930 128 2.29 — — 0.375 BROCO 24.5 35.5 152.4 0.630 0.912 140 2.50 — — 0.368 BROCO + 23.0 28.0 139.6 0.645 0.786 110 1.97 — — 0.316 graphoil Outlet Pressure = 50 psi; Oxygen Flow = 235 l/min; Steel Plate; Thickness = 7.0 cm BROCO 7.0 56 289.3 0.095 0.758 220 3.94 — — 0.305 BROCO + 9.5 40.5 222.9 0.169 0.721 159 2.85 — — 0.287 graphoil BROCO 8.5 65 309.1 0.108 0.824 256 4.58 — — 0.332 BROCO + 10.0 37.5 235.4 0.166 0.624 147 2.64 — — 0.251 graphoil Outlet Pressure = 80 psi; Oxygen Flow = 80 l/min; Steel Plate; Thickness = 1.1 cm BROCO 26.0 34.5 49.8 0.696 0.924 136 2.43 — — 1.093 BROCO + 26.0 13.5 40.7 0.851 1.097 53 0.95 — — 0.523 graphoil Al + 7 Fe 25.0 28.5 45.2 0.738 0.841 86 1.54 — — 0.764 wire + graphoil (A) BROCO 26.0 30.0 44.4 0.779 0.899 118 2.11 — — 1.066 BROCO + 25.5 26.5 37.4 0.909 0.945 104 1.87 — — 1.117 graphoil (A) Al + 7 Fe 25.5 37.0 44.7 0.760 1.103 — — 1.003 wire + graphoil BROCO 26.0 30.0 39.9 0.868 1.002 118 2.11 — — 1.186 Al + 7 Fe 26.0 22.5 35.76 0.969 0.839 68 1.22 — — 0.684 wire + graphoil (B) Al + 7 Fe 26.0 26.0 34.7 1.124 1.124 79 1.41 — — 0.908 wire + graphoil (B) Outlet Pressure = 80 psi; Oxygen Flow = 80 l/min; Steel Plate; Thickness = 5.7 cm Al + 7 Fe 7.5 34.0 51.6 0.194 0.878 103 1.84 — — 0.799 wire + graphoil (B) BROCO 5.5 46.0 76.6 0.096 0.801 181 3.24 — — 0.947 [0079] [0079] TABLE 4 Time Length O 2 Needed Needed to of for the Lance Molar Make a 15 Lance Run (@ Pierce Burning Material Burned ratio Type of cm Hole Burned 80 l/min) Rate Rate Fe C 2 F 4 Lance: O 2 Lance (sec) (cm) (liters) (cm/sec) (cm/sec) g mol g mol Mol/mol BROCO 194.88 258.5 259.84 0.077 1.326 1017 18.2 — — 1.57 BROCO + 88.4 84.0 117.87 0.170 0.950 381 6.8 102 1.0 1.48 PCTFE + FE (10″) BROCO + 105.31 104.0 140.41 0.142 0.988 459 8.3 127 1.3 1.53 PCTFE (foil) BROCO + 99.93 95.0 133.24 0.150 0.951 424 7.5 116 1.2 1.46 PCTFE + Fe (10″)

A high-speed chemical drill ( 20 ) for removing portions of a target material ( 30 ), comprises: an elongated tube ( 21 ) formed of a fuel material; a source ( 24 ) of oxidizer; a conduit ( 26 ) for establishing a controllable flow of oxidizer from said source through said tube; and a sleeve ( 28 ) formed of a material containing chlorine and/or fluorine mounted on said tube; whereby, when said drill is ignited and used to remove portions of a target material, the chlorine and/or fluorine in said sleeve material will react chemically with the target material to form gaseous reaction products.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE This application is the U.S. national stage filing of International Application No. PCT/EP2007/011025 filed Dec. 14, 2007, which claims priority to German patent application no. 10 2006 061 035.0 filed Dec. 22, 2006. TECHNICAL FIELD The present invention relates to a plastic profile for window-, door- and facade-elements. RELATED ART Window systems generally are comprised of a wing profile and a frame profile, wherein the wing is glazed and the frame is connected with the building-shell (brickwork). These profiles are, for example, made of wood, steel, aluminum, plastic or combinations of these materials. The diversity of the competing materials is partly based on tradition; however, the factors thermal properties, wind-resistance, maintenance and maintenance costs, aesthetic impression and price are also important for the selection of the material. Extruded plastic hollow profiles for windows and doors are known in the prior art (e.g., DE 33 19 144A1), in which the hollow profile part has a plurality of hollow chambers that extend along the hollow profile member. Such hollow profile parts are usually made of rigid PVC. One or more of the internal chambers can be filled with foamed plastic (see also EP 1 154 115 B1). The corner connection of window frames made of such hollow profiles is manufactured by welding or by the use of corner connectors, which are adhered in place. Window systems (e.g. under the designation Corona CT 70 Plus) having foam-free plastic hollow profiles with a plurality of hollow chambers and conventional steel reinforcement are offered by the window manufacturer Schüco of Bielefeld, Germany, wherein steel-reinforced profiles are inserted into hollow chambers. The steel-reinforced profiles are also used for anchoring of fittings. In these window-systems, the attachment of decorative external covers made of aluminum is possible. Profile members made of plastic-foam for window elements are known from DE 201 05 876 U1, DE 32 42 909 A1 and WO 97/22779 A1, respectively, in which insulating frames (DE 201 05 876 U1) or profile parts made of metal (DE 32 42 909 A1) or also profile parts made of wood or plastics (WO 97/22779 A1) are connected with the core made of plastic foam in different ways. In the PU-foam core known from DE 201 05 876 U1, separate core-profiles are provided in the PU-profile. A plastic profile component for window and door elements is known from EP 1 705 334 A2, wherein metal profile parts are adhered to, or also rolled into, both outer sides of the plastic profile part, which outer sides form the interior and exterior sides of the window and door element. Furthermore, aluminum window, door and facade elements, which are comprised of weather-side and interior-side aluminum profiles made of aluminum-plastic-composite profiles, are known, which aluminum profiles are friction-fit/form-fit connected to plastic profiles. In the manufacturing of the components, the profiles are assembled into frames, wherein the corners are mechanically connected via inserted corner connectors. Moreover, composite window, door and facade elements, which are comprised of weather-side and interior-side profiles made of composite profiles using freely-selectable materials, are known, which are friction-fit/form-fit connected to plastic profiles (EP 1 555 376 A1). DE 200 16 611 U1 discloses a reinforced plastic window profile for windows, etc., wherein a U-shaped groove for accommodating fittings, etc. is provided; a reinforcement profile is affixed in the groove. SUMMARY It is an object of the invention to provide an improved plastic profile for window, door and facade elements and a reinforced plastic profile having such a plastic profile for window, door and facade elements. A profile system for windows, doors and facades is enabled by the invention, wherein hollow profiles made of plastic and having rolled-in reinforcements are utilized, which reinforcements are installed in a positionally-precise and longitudinally-fixed manner and which make possible an insulating zone that is a comparatively large proportion of the total constructional depth. One embodiment of an inventive profile system for windows, doors and facades comprises plastic profiles, preferably made of plastic hollow profiles, and outwardly-disposed reinforcement profiles, preferably made of aluminum, which have an accommodation chamber for corner connection elements precisely positioned relative to the outer surface and which are connected in a longitudinally-fixed manner with the plastic hollow-profile using a roll-in process. The plastic profile forms an insulating zone and the proportion of the insulating zone relative to the total constructional depth from the interior side to the weather side preferably is 80% or more, even more preferably 90% or more, or even more preferably, 95% or more. The profiles can be connected, in a manner analogous to aluminum windows, via corner connectors to components such as window, door and facade elements. A manufacturing method is used for the manufacture of the plastic profiles made of, e.g., rigid-PVC, PA, PET, PBT, PA/PPE, ASA (reinforced or not reinforced) or others, which calibrates the external contour as well as the internal contour in a positionally-precise manner. A precision can be ensured by the positionally-precise calibration, with which inserted and affixed reinforcements are positioned relative to the external contour with the required low tolerances. The invention offers several advantages for designing the properties of window, doors and facade elements, in which the reinforced plastic profile is utilized. a) Thermal Properties The thermal rating can be determined by the increased proportion of the plastic hollow profiles in the constructional depth and by the configuration, size and partitioning of the interior hollow spaces, as well as the foam filling thereof. b) Mechanical Properties The mechanical properties, such as torsional resistance, etc., can be determined by the constructional depth (i.e. the distance between the weather-side and the interior-side reinforcements) and by the configuration, size and cross-sectional area of the reinforcements. c) Cross-Section In the cross-section of the profiles, undercuts and geometries of arbitrary complexity for accommodating fitting and locking elements, seals, etc., are made possible by the use of the plastic hollow profiles. d) Surface and Coloration The surface and coloration may also be varied in many ways for the differing designs of the weather side and the interior side by the choice and pigmentation of the plastics and/or through the use of decorative elements. The external contour of the hollow profile is determined by the required functions, such as e.g.: a) sealing receptacle, sealing stop, fitting receptacle in the closing plane; b) block surfaces, functional grooves for the glass guide rail, glass seal receptacle, and drainage for the glazing, c) grooves, window sill stop, receptacle for sealing films, etc., for the building shell (brickwork), and d) glossy, colored and weather-proof surfaces of the hollow profile and/or latches for the attachment of decorative profiles made of plastic, wood, aluminum or stainless steel (extruded or rolled) for the external and interior sides. The reinforcement preferably comprises extruded aluminum hollow profiles having an interior contour for the accommodation of corner connectors (as is usual for aluminum windows) and an external contour having positioning surfaces for the precise fixing of the position in the plastic hollow profile. The reinforcements can have additional functions such as are required for the threaded connection of T-joints or fittings. The plastic hollow profiles are preferably comprised of reinforced materials, e.g. PA 66 GF, and include functional elements on the external contour, e.g. for the accommodation of fitting and locking elements, seals, glass guide rails, accommodation of decorative covers and the like. The plastic hollow-profiles for windows, doors and facades achieve a satisfactory static bearing capacity due to the reinforcement profiles, which are connected in a longitudinally-fixed manner and are preferably formed of aluminum. The reinforcement profiles preferably include a portion that is suitable for the accommodation of corner connectors. Preferably, functional portions for the accommodation of fitting and locking elements, seals, glass guide rails can be integrated into the plastic hollow profile. The reinforcement profiles preferably can be covered with decorative covers. The plastic hollow profiles fulfill application-specific mechanical requirements by selecting a suitable plastic material, e.g. PA 66 GF. The reinforcement-profiles can be prepared in a suitable manner for the longitudinally-fixed connection with the plastic profile, e.g. by knurling. BRIEF DESCRIPTION OF THE DRAWING Further features and utilities will be derived from the description of embodiments with the assistance of the figures. In the figures: FIG. 1 shows a cross-sectional view perpendicular to the longitudinal direction of a reinforced plastic profile according to a first embodiment of the invention; FIG. 2 shows a cross-sectional view perpendicular to the longitudinal direction of a plastic profile according to a second embodiment of the invention; FIG. 3 shows a cross-sectional view perpendicular to the longitudinal direction of a plastic profile according to a third embodiment of the invention; FIG. 4 shows a cross-sectional view perpendicular to the longitudinal direction of a reinforced plastic profile according to a fourth embodiment of the invention; FIG. 5 shows a cross-sectional view perpendicular to the longitudinal direction of a reinforced plastic profile according to a fifth embodiment of the invention; and FIG. 6 shows an enlarged view of a portion of the first embodiment from FIG. 1 . DETAILED DESCRIPTION OF THE INVENTION A first embodiment of the invention will be described with reference to FIG. 1 and FIG. 6 . FIG. 1 shows profile parts as components of a frame profile and of a window wing profile in the cross-section (x-y plane) perpendicular to the longitudinal direction (z) of the respective profile members. On the right-hand side of FIG. 1 , a plastic hollow profile 111 is shown in the cross-section perpendicular to its longitudinal direction, which profile 111 forms a part of a window wing. A double-glass window pane 200 can be retained at/in the frame of the window wing in a known manner via sealing/attachment elements 201 , which may also formed in a different shape, and a glass guide rail 202 . The top side in FIG. 1 is the interior side and the bottom side in FIG. 1 is the weather side of the profile members. The plastic hollow profile 111 , which forms a part of a window wing, extends in a transverse direction x perpendicular to the longitudinal direction z and perpendicular to a width direction y, which in turn is perpendicular to the longitudinal direction z, from the weather side (bottom side in FIG. 1 ) to the interior side (top side in FIG. 1 ). An aluminum hollow profile 21 is affixed to the plastic hollow profile 111 on an external side (weather side) in a manner described below. On the opposite side in transverse direction x, i.e. on the interior side (top side in FIG. 1 ), an aluminum hollow profile 22 is affixed in a similar manner. A hollow chamber is located between the two outer sides, which in the first embodiment is foam-filled with a foam 50 having a low density. In the cross-section (x-y) perpendicular to its longitudinal direction z, the plastic hollow profile has a complex geometry with undercuts, protrusions and the like for the accommodation of fitting and locking elements (not shown), seals 201 , 211 , 212 , reinforcement rails 23 and other elements such as the window rail 202 and/or for the mounting of decorative elements 61 . The attachment of the aluminum hollow profiles 21 , 22 will now be described with reference to FIG. 6 in an exemplary manner for the aluminum hollow profile 21 . As can be clearly seen in FIG. 6 , the plastic hollow profile 111 includes roll-in protrusions, such as the roll-in protrusions 121 a , at the respective outer side (in this case the weather side), which protrude from the plastic hollow profile 111 in the transverse direction x and thus form the farthest protruding sections/parts of the plastic hollow profile 111 on this outer side. The aluminum profile 21 extends in the longitudinal direction z and has a hollow chamber 21 a surrounded by an outer wall having a rectangular shape in cross-section. The hollow chamber may, of course, also have other cross-sectional shapes, but a rectangular cross-section, the longer side of which extends in the width direction y, is preferred. Protrusions 21 b extend from the rectangular wall in width direction y; the ends of these protrusions are formed as bendable hammers (roll-in hammers) 21 ba for rolling-in and form the groove together with another part of the aluminum hollow profile (in this case, the wall of the hollow chamber). As can be clearly seen in FIG. 6 , the roll-in protrusions 121 a of the plastic hollow profile 111 are formed in a suitable bent shape such that the tips, as the heads (roll-in heads) 121 aa of the roll-in protrusions 121 a , cooperate with the hammers 21 ba of the protrusions 21 b of the aluminum hollow profile 21 to retain the aluminum profile 21 in a longitudinally-fixed manner, and such that the aluminum profile 21 comes into contact with the plastic hollow profile 111 only at the heads 121 aa . The aluminum profile 21 is accommodated in a receptacle (recess) 121 such that it is surrounded by an air cushion and does not otherwise come into contact with the plastic hollow profile 111 . This means that the length of the protrusions 121 a , i.e., the extension of the protrusion relative to the wall 121 b , which bounds the receptacle 121 , is determined such that the depth of the aluminum profile 21 is less than the length of the protrusions 121 a in the transverse direction x. The above explanations for the configuration of the roll-in protrusions and of the aluminum hollow profiles apply to all embodiments. The wall 121 b is, in principle, not required for the inside boundary of the receptacle 121 , as will be explained further below with reference to FIGS. 4 and 5 . However, an inside boundary of the receptacle 121 is provided and preferred in the present first embodiment. As shown in FIG. 1 , the aluminum hollow profile 22 is affixed to roll-in protrusions 122 a , 122 c on the opposite outer side (interior side) of the plastic hollow profile 111 in a longitudinally-fixed manner by rolling-in in a similar way. Here, the roll-in protrusions 122 a , 122 c are not formed with the same length, which is different than the case of the weather side. However, the roll-in protrusions 122 a and 122 c are also the sections/parts of the plastic hollow profile 111 that project the farthest in the transverse direction x on the interior side. The aluminum hollow profile 22 has a hollow chamber 22 a , which is surrounded by a wall having a rectangular cross-section, and protrusions 22 b , 22 c extending in the width direction y. Unlike in the aluminum hollow profile 21 , these protrusions are adapted to realize further functions. For example, the protrusion 22 b includes another protrusion 22 bb , in addition to the hammer 22 ba for rolling-in, which protrusion 22 bb serves to click-attach a decorative element 62 . The protrusion 22 c includes the hammer 22 ca for rolling-in and an extension 22 cb , on which a receptacle 22 cc for the seal 211 and a protrusion 22 cd for the click-attachment of the decorative element 62 are provided. In principle, the aluminum hollow profiles 21 , 22 serve as reinforcement elements that are connected to the plastic hollow profile 111 in a longitudinally-fixed manner by rolling-in. In this way, the mechanical properties of a reinforced plastic hollow profile, which is comprised of the plastic hollow profile 111 and the aluminum hollow profiles 21 , 22 , are achieved. By constructing a plastic hollow profile 111 such that the roll-in protrusions 121 a , 122 a , 122 c are the farthest protruding sections/parts of the plastic hollow-profile 111 in the transverse direction x, and by disposing the substantial part of the aluminum hollow profile substantially between the roll-in protrusions, or expressed more generally, within the plastic hollow profile, a maximum enlargement of the insulating zone formed from plastic is achieved relative to the total constructional depth in transverse direction x. Different from known composite profiles, the enlargement of the cross-section of the aluminum hollow-profile in transverse direction x is not added to the size of the insulating zone, but rather in the present case the largest part of the enlargement of the cross-section of the aluminum hollow profile in the transverse direction x is within the enlargement of the insulating zone in the transverse direction x, without reducing the enlargement of insulating zone x. As a result thereof, the proportion of the insulating zone relative to the total constructional depth in the transverse direction x of at least 80%, in the present case (without decorative covers) of even 92% in the case of the plastic hollow profile 111 reinforced with aluminum hollow profiles 21 , 22 , is achieved. By appropriately modifying the protrusion 22 c and extending the roll-in protrusion 122 c to the length of roll-in protrusion 122 a , even 96% is possible. The decorative elements 61 , 62 can, for example, be formed as aluminum covers that can be clipped onto the profile. Other materials such as stainless steel, wood, plastic, etc. can also be used for the decorative elements 61 , 62 . It should be considered that the use of a material for the decorative covers that conducts heat very well, especially when the decorative covers extend further in transverse direction x to the inner side of the plastic hollow profile 111 , like the decorative cover 61 (in contrast to decorative cover 62 ), causes a deterioration of the insulating properties, which is, however, much smaller than the improvement achieved through the described connection of the aluminum hollow profiles with the plastic hollow profile. Moreover, these decorative elements can be formed very thin-walled, so that further optimizations are possible here, too. As was already described above, the plastic hollow profile 111 has a complex geometry. The plastic hollow profile 111 , for example, has an undercut recess 131 that is adapted for the accommodation of fittings and locking elements. In the subsequent description, reference to FIG. 2 is made, the plastic hollow profile 111 of which is identical with the plastic hollow profile 111 of the first embodiment. The recess 131 extends in the longitudinal direction z. In the width direction y, the outer wall of the plastic hollow profile 111 forms the back wall of the undercut recess 131 . In transverse direction x, the recess 131 is bounded on the interior side by a hook-shaped protrusion 131 a . In the transverse direction x, on the weather side, the outer wall of the plastic hollow profile 111 extends at a right angle from the part that forms the back wall and includes a protrusion 131 b protruding towards the interior side, so that the undercut recess 131 is bounded as a whole. Another undercut recess 132 is formed on the inner side of the back wall of the undercut recess 131 . The undercut recess 132 is bounded by the same part of the outer wall of the plastic hollow profile 111 as the back wall in the width direction y. In the transverse direction x, on the weather side, the recess 132 is bounded by a hook-shaped protrusion 132 b and on the interior side by the outer wall of the plastic hollow profile 111 and by a protrusion 132 a protruding at a right angle from this outer wall towards the weather side. The recess 132 forms a receptacle for a reinforcement element (reinforcement bar) 23 , whose function is the secure attachment of the fitting and locking elements, which are received in the undercut recess 131 on the outer side. The reinforcement element 23 is held in its position by the foam 50 or in another way (e.g. screws). The plastic hollow profile 111 of the first embodiment has a hollow chamber that is continuous from the interior side to the weather side. This hollow chamber is foam-filled with the foam 50 for reasons of heat insulation and strength enhancement. Depending on the requirements, the plastic hollow profile can have one or more hollow chambers that are foam-filled entirely, partially or not at all. The density of the foam that is used can be varied depending on the requirements. On the left hand side of FIG. 1 , a plastic hollow profile 112 is shown that is a part of a frame profile. Aluminum hollow profiles 24 , 25 are connected in a longitudinally-fixed manner to the plastic hollow profile 112 via roll-in protrusions 124 a , 125 a by rolling-in in the same manner as in the plastic hollow profile 111 . The plastic hollow profile 112 also has a hollow chamber that is continuous from the weather side to the interior side, which hollow chamber is foam-filled with a foam 50 . In a comparable manner, the aluminum profiles 24 , 25 have hollow chambers 24 a , 25 a surrounded by outer walls that are rectangular in cross-section. In the hollow profile 112 too, the roll-in protrusions 124 a together with a corresponding outer wall 124 b of the plastic hollow profile 112 form a receptacle 124 , into which the hollow chamber 24 a of the aluminum hollow profile is inserted. The aluminum hollow profile 24 is again in contact only with the heads 124 aa of the roll-in protrusions 124 a of the plastic hollow profile 112 and is otherwise surrounded by an insulating air layer. The same can be said about the longitudinally-fixed attachment of the aluminum hollow profile 25 by rolling-in, wherein the receptacle 125 is bounded by the roll-in protrusions 125 a and the outer wall 125 b . The plastic hollow profile 112 reinforced with the aluminum profile 25 has an undercut recess 133 for accommodation of locking and fitting elements. Different from the undercut recess 131 of the plastic hollow profile 111 , this recess is not exclusively formed by the plastic hollow profile, but rather by the combination of the plastic hollow profile 112 with the aluminum hollow profile 25 . This means the undercut recess is partly formed by components (outer wall, protrusions) 133 b , 133 a of the plastic hollow profile and partly by components (protrusion 25 b ) of the aluminum hollow profile 25 . In the embodiment shown in FIG. 1 , no reinforcement element for the secure attachment of the fitting and locking elements is provided. It can, however, be made in various ways, as is described with reference to FIGS. 2 and 3 . As can be derived from the description of the first embodiment, the plastic hollow profile makes possible a significant increase of the proportion of the insulating zone out of the total construction depth for comparable constructional depths. This is made possible, for example, by the fact that the roll-in protrusions on the respective outer side are the farthest protruding sections/parts of the plastic hollow profile. If the reinforcement element is formed with a hollow profile, the hollow profile is to be arranged in a way that it is located substantially (at least more than 50%) within the constructional depth in the transverse direction x, preferably to the largest extent, i.e. 80% or more, more preferably 90% or more, even more preferably completely except for the outer wall, relative to the protruding of the roll-in protrusions, preferably between the roll-in protrusions. The reinforcement elements and the hollow chambers 21 a , 22 a , 24 a , 25 a , respectively, of the aluminum hollow profiles can preferably be used as the receptacle portion for accommodating a corner connector. The aluminum hollow profiles are preferably manufactured by aluminum extrusion, so that the cross-section of the aluminum hollow profiles is identical over the entire length in the longitudinal direction. In this case, the hollow profile and thus also the receptacle portion for the accommodation of a corner connector, is located between the roll-in protrusions in the above described manner. The reinforcement elements can also be formed as partially-open profiles. In this context, partially-open profile means a profile that has a cross-sectional shape (e.g. a U-shape or the like) in its cross-section (x-y) perpendicular to its longitudinal direction z, which partially, but not entirely, surrounds a space. A further example of a partially-open profile is a rectangular profile that is not completely closed on one side of the rectangle, and the like. The plastic hollow profiles 111 , 112 possess a positionally-precise calibration of the roll-in protrusions relative to the outer geometry of the plastic hollow profiles, so that the aluminum hollow profiles and the receptacle portions for the corner connectors, respectively, can be positioned by means of the longitudinally-fixed rolling-in in a positionally-precise manner relative to the outer geometry. Consequently, a positionally-precise connection of the reinforced plastic hollow profiles via corner connectors or via other corner connections, such as e.g., welding, is possible and the time and effort of the post-processing work of such corner connections is minimized. In the following, a method for manufacturing the plastic hollow profiles shown in FIG. 1 and FIG. 6 will be described. Methods and devices for manufacturing a hollow chamber profile, with which individual components or the entire hollow chamber profile can be calibrated in a positionally-precise manner, are described in the WO 96/30188 A1 and the DE 199 21 458 A1 respectively. The plastic hollow profiles 111 , 112 of the first embodiment are manufactured using suitable methods, wherein materials are chosen that are color-, light- and/or weather-proof, depending on the requirements. In this manufacturing, the profiles are extruded and preferably at least the outer surfaces and the roll-in protrusions are calibrated in a positionally-precise manner. Suitable materials are rigid-PVC, PA, PET, PPT, PA/PPE, ASA, PA66 and others (each with or without reinforcement materials). The reinforcement parts are preferably manufactured by aluminum extrusion. The protrusions of the reinforcement parts, which have to be rolled-in, are preferably prepared by knurling. Thermosetting plastics, such as PU, having an appropriate density can be used as foams for foam-filling the plastic hollow profiles. Preferably, foams having a low density (0.01 to 0.3 kg/l) are used. If foam having a high density is to be used, foams with 0.3 to 0.6 kg/l are preferably used. With the above described embodiment, arbitrary undercuts are possible at arbitrary locations of the profile. The surface treatment of outer and inner covers made of aluminum or other materials can be carried out independent of a foaming process, which is advantageous, in case the foam does not tolerate annealing temperatures. In addition to this advantage, the described embodiment provides a system with excellent mechanical properties, wherein the reinforcement profiles can be used for the corner connection using corner connectors and, at the same time, the necessary post-processing work is minimized. The embodiment also enables the use of foams of different density and the resulting optimization of heat conducting properties. The described embodiment enables proportions of the insulating zone formed from plastic of 95% or more, in any case of 80% or more of the total construction depth, with excellent mechanical properties that are achieved due to the longitudinally-fixed rolling-in of the aluminum hollow profiles. A second embodiment is described with reference to FIG. 2 . In the second embodiment, the window wing profile is identical to the window wing profile of the first embodiment and therefore the description is not repeated. The frame profile includes a plastic hollow profile 113 whose design corresponds to the plastic hollow profile 112 of the first embodiment, except for the formation of the recess 125 and the recess 134 ; a reinforcement element 27 is inserted in the recess 134 . As can be clearly seen in FIG. 2 , the outer wall 125 b does not extend to the outer wall 133 b , but rather transitions into the wall 125 c shortly before the outer wall 133 b ; the wall 125 c forms an outer wall for bounding the receptacle 125 . In this way, the undercut recess 134 is formed, which is located at the inner side of the outer wall 133 b opposite to the undercut recess 133 . A reinforcement element 27 is inserted into this undercut recess 134 , which reinforcement element 27 serves to securely attach fitting and locking elements that are guided in the undercut recess 133 , analogous to the reinforcement 23 . The remaining design of the plastic hollow profile 113 corresponds to the design of the plastic hollow profile 112 of the first embodiment, and therefore, the description is not repeated. A third embodiment is described with reference to FIG. 3 . The window wing profile of the third embodiment corresponds to the window wing profile of the first and second embodiments, and therefore, the description is not repeated here. The frame profile of the third embodiment differs from the frame profiles of the first and second embodiments in the formation of the receptacle 126 and of the aluminum hollow profile 26 . As can be clearly seen in FIG. 3 , the aluminum hollow profile 26 is rolled-in at the interior side of the frame profile in a known manner. The shape of the aluminum hollow profile 26 corresponds to the shape of the aluminum hollow profile 25 , except for the protrusion 26 c that protrudes on the interior side of the aluminum hollow profile 26 in the width direction y and that forms a reinforcement element that extends in the transverse direction x and the longitudinal direction z. A receptacle 126 is bounded by roll-in protrusions 126 a , the tips 126 aa of which serve as roll-in protrusions for the protrusions 26 ba of the aluminum profile 26 . For accommodating the reinforcement element 26 c , the receptacle 126 is provided with a recess extending in the transverse direction x and the longitudinal direction z, which is bounded by a wall 126 c , so that the reinforcement element 26 c extends, like the reinforcement element 27 , on the inner side of the outer wall 133 b opposed to the undercut recess 133 . Therefore, the reinforcement element 26 c can fulfil essentially the same function as the reinforcement element 27 . A fourth embodiment is described with reference to FIG. 4 . The fourth embodiment differs from the second embodiment in that the integral plastic hollow profiles 111 and 113 are replaced by multi-part plastic hollow profiles 115 and 116 . The remaining design corresponds to the design of the second embodiment. Unlike the plastic hollow profile 111 , the plastic hollow profile 115 of the window wing profile is not integrally formed, but rather is formed of a plurality of parts. The outer walls 115 a are connected via an inner element 115 b that forms inner bars (e.g. via not-illustrated plug-in, clip-on or other connections). The use of the inner bars 115 b increases the mechanical rigidity and results in the formation of a plurality of hollow chambers. These hollow chambers can optionally be entirely or partially foam-filled. The plastic hollow profile 116 , which replaces the plastic hollow profile 113 of the second embodiment, is formed in a similar way. This means the outer walls 116 a are connected via an inner part 116 b that forms inner bars, wherein a plurality of hollow chambers is formed. A fifth embodiment will be described with reference to FIG. 5 . The fifth embodiment differs from the third embodiment in the design of the plastic hollow profiles 115 and 117 . The window wing profile of the fifth embodiment corresponds to the window wing profile of the fourth embodiment, and therefore, the description is not repeated here. As compared to the frame profile of the fourth embodiment, the frame profile of the fifth embodiment has an aluminum hollow profile 26 instead of the aluminum profile 25 that is provided in the third embodiment. The plastic hollow profile 117 of the fifth embodiment merely differs from the plastic hollow profile 116 of the fourth embodiment in that no undercut recess for the accommodation of the reinforcement element 27 is formed. Instead, the reinforcement element 26 c , which is an integral component of the aluminum hollow profile 26 , is located on the inner side of the outer wall 133 b that forms the back wall of the undercut recess 133 . The remaining design of the fifth embodiment corresponds to the design of the fourth embodiment and is therefore omitted. The manufacturing method described for the first embodiment and the properties and advantages described for the first embodiment are also applicable or are maintained in the second to fifth embodiments. The features of the first to fifth embodiments can be freely combined according to the requirements. It is explicitly stated that all features disclosed in the description and/or the claims, should be regarded as separate and independent of each other for the purpose of original disclosure as well as for the purpose of restricting the claimed invention, independent of the combination of features in the embodiments and/or the claims. It is explicitly stated that all indications of ranges or of groups of units disclose every possible intermediate value or sub-group of units for the purpose of original disclosure as well as for the purpose of restricting the claimed invention, especially also as a limit of a range indication.

A plastic profile for window, door and facade elements includes a plastic profile body, which extends in a longitudinal direction (z), and at least one outer side, which is located outside in a transverse direction (x) perpendicular to the longitudinal direction (z) as viewed in a cross-section (x-y) perpendicular to the longitudinal direction (z). The outer side includes two roll-in protrusions configured such that a reinforcement element is connectable with the plastic profile body by a rolled-in connection. The reinforcement element has at least one of a hollow profile, a partially-open profile and a receptacle portion configured to accommodate a corner connector, wherein at least one of the hollow profile, the partially-open profile and the receptacle portion is disposed between the roll-in protrusions in the rolled-in state.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) to United Kingdom patent application number GB 1320205.6 filed Nov. 15, 2013, the disclosure of which is hereby incorporated in its entirety by reference in its entirety. TECHNICAL FIELD [0002] The present invention relates to improved arrangements for slug mitigation in subsea pipelines, such as risers, as used in the oil and gas industry and particularly, according to the invention, utilising an in line separator apparatus in such arrangements. BACKGROUND TO THE INVENTION [0003] In-line separator devices are known in the art. For example, WO2008/020155 and WO2009/047484 each describe improved in-line separator arrangements; also known as cyclonic and/or uniaxial separators. FIG. 1 illustrates an in-line separator according to WO2008/020155 which is referred to commercially as an “I-SEP”. Furthermore, embodiments described by WO2009/047484 are known commercially as “Hi-SEP”, illustrated by FIG. 2 . [0004] Likewise, jet pumps (a.k.a. surface jet pumps, SJPs, eductors or ejecters) are known. For example, EP0717818 relates to a surface jet pump where flow from a high pressure oil well is used to reduce the back pressure on low pressure wells. According to this document the source of motive flow is a high pressure well and the low pressure well is not gas lifted. This jet pump also incorporates an in-line separator, as illustrated by FIG. 3 . [0005] It has been recognised by the present inventors that: An I-SEP has been shown to absorb slug energy and calm the fluid flow down stream By making use of I-SEP technology it is possible to mitigate slug flow in pipelines and severe slugging in pipeline/riser systems An I-SEP has also been seen to influence flow regimes upstream in the piping and risers By making use of the I-SEP technology it is possible to mitigate slug flow at a higher production rate, i.e. less back pressure is required to mitigate the slug flow It is also possible to mitigate slug flow while producing a complete gas-liquid separation, thus debottlenecking the main 1 st stage separator using this technology This system is applicable for any slugging type/situation BRIEF DESCRIPTION OF THE DRAWINGS [0012] FIG. 1 illustrates a section view of a prior art in-line separator; [0013] FIG. 2 illustrates a section orthographic view of another prior art in-line separator; [0014] FIG. 3 illustrates a prior art surface jet pump; [0015] FIG. 4 illustrates a general pipeline/riser system known in the art; [0016] FIG. 5 illustrates four cyclical stages of severe slugging, known in the art; [0017] FIG. 6 illustrates a system having a control/choke valve situated at the top of a riser; [0018] FIG. 7 illustrates as system having an I-SEP and control valve at a top of a riser; [0019] FIG. 8 illustrates an example of how an I-SEP/Hi-SEP combination could be used; [0020] FIG. 9 illustrates a similar design to mitigate severe slugging and perform a gas-liquid separation; and [0021] FIG. 10 illustrates an example of making use of the I-SEP for slug mitigation and a jet pump (SJP). DETAILED DESCRIPTION OF THE INVENTION [0022] The invention has been designed to specifically reduce the effect of slugging on a pipeline riser/pipeline system for offshore oil and gas use. FIG. 4 shows a general pipeline/riser system where the flow from the wellhead flows along the seabed and enters a typical riser configuration 11 which connects the seabed pipeline to the topside processing/separation equipment, e.g. a first stage separator 12 . The systems described herein can be used for severe slugging or any terrain induced slug flow that may be generated from the profile of a pipeline. A typical severe slugging regime has been used as an example to describe a solution but the invention is equally as effective for any slug flow regime. [0023] One of the major issues associated with the type of system illustrated by FIG. 4 is a flow regime described as severe slugging (mentioned above). Severe slugging occurs generally in four cyclical stages, as can be seen in FIG. 5 . Severe slugging is the occurrence of a liquid slug that is at least one riser height in length and can be hundreds of metres in length. It is also known as terrain induced slugging because it usually occurs due to low points in a pipeline. [0024] The most common four stages shown in FIG. 5 represent the cyclic nature of severe slugging, namely: Stage 1: Liquid Fall Back—From the end of the previous cycle there is some liquid fall back down to the low point of the riser. Along with constant inflow of new liquids this causes a blockage at the base of the riser and starts the next cycle. Stage 2: Slug Formation—the liquid continues to build up in the riser as a liquid slug. Pressure builds up behind this liquid slug as gas continues to flow into the pipeline. Stage 3: Slug Production—once the liquid reaches the top of the riser the hydrostatic head can no longer increase and therefore gas pressure overcomes the liquid head and a liquid slug starts to be produced. Stage 4: Blowout—Once the tail of the slug reaches the base of the riser the gas breaks through and into the riser, expanding to cause a violent acceleration of the liquid slug; after which some liquid falls back down the riser and blocks the riser base thus commencing the next cycle (stage 1). [0029] The main issues associated with production whilst in the severe slugging regime occur due to flooding of the separation systems during the slug production phase of the cycle resulting in poor separation and over pressurisation during the slug blow out stage which can cause the platform to shut down completely. For example, export compressors go into surge mode due to significant variation in the gas flowrates, imposing stress on the shaft/bearings and operational control issues. Sometimes this leads to unwanted flaring of the gas. Furthermore, cyclic surges introduce vibration to the process piping system and mechanical fatigue to the riser, leading to possible earlier failure. Accordingly, it is important that this flow regime can be controlled or mitigated. [0030] Severe slugging can be managed by making use of slug catchers on the topside facilities but these are generally large vessels designed to hold the full liquid slug, thus mitigating any issues of flooding the separation trains. Slug catchers are typically very large and heavy as they have to be designed to withstand the high pressures observed during blowout. As footprint and weight are very important parameters for an offshore platform, there is generally not sufficient space or capability to carry the weight associated with the need for slug catchers. Accordingly, a more compact system is required. [0031] FIG. 6 shows a system that is recognised as a simple fix in the field, namely a control/choke valve 13 situated at the top of the riser 11 that, by throttling the control/choke valve actively imposes a back pressure on the riser which slows down incoming flow, hence restricts the production rate. During the blowout stage of a severe slugging cycle, the higher back pressure acts to decelerate the liquid slug forcing it to mix with the gas in the riser, ultimately stabilising the flow. This method forces the operator to accept a reduction in production to achieve stable flow and may cause some wells to be abandoned. In some cases, the flow is sheared going to downstream processes and makes separation of phases difficult. [0032] If a system can be found that mitigates the severe slugging regime whilst imposing a smaller back pressure on the base of the riser (resulting in changing of the flow regime in the riser and increasing the stable flow region) this will result in a higher production for the operator in a stable manner with minimum operational upsets. [0033] Slug mitigation is possible by an I-SEP alone, but from experimental testing, it has become apparent that by making use of an I-SEP and control valve at the top of the riser, the system could act in a improved way to the use of the throttling valve. Such a system is illustrated by FIG. 7 where an I-SEP 14 is located downstream of the riser 11 (above sea level) and upstream of a throttling valve 15 . However, as illustrated, gas separated at the I-SEP 14 is shown to be able to bypass the throttling valve in a bypass line 16 before re-joining the main pipeline prior to connection with the first stage separator 12 . [0034] The valve 15 could be substituted by a fixed restriction to add a minor pressure loss, such as a smaller outlet of the I-SEP or a built in orifice plate. This would allow partially separated gas to be reintroduced and mixed before entering the main separator. The mixing point could be a commingler (not illustrated). [0035] Testing has shown that by making use of this system it is possible to mitigate the severe slugging regime with a lower back pressure compared to a control/choke valve ( 13 ) only. Early test results and computer simulations have shown that a 10-20% saving in pressure loss can be observed by making use of an I-SEP 14 rather than the control valve; this would result in a higher production rate by making use of the I-SEP rather than the control valve alone. [0036] A further advantage of making use of an I-SEP device is its ability to separate gas and liquid that could be beneficial for pipeline riser systems where the first stage separator needs de-bottlenecking. FIG. 8 shows an example of how an I-SEP/Hi-SEP 14 / 17 combination could be used to mitigate severe slugging and perform a pre-separation on the fluids prior to entering the main separation train. The Hi-SEP component 17 (as described by WO2009/047484) is located downstream of the I-SEP 14 , where dense fluid separated therein is piped via a control valve to the first stage separator 12 . Gas separated in the Hi-SEP 17 can be piped via a control valve 18 to a compressor. [0037] FIG. 9 shows a similar design to that of FIG. 8 that can be used to mitigate severe slugging and perform a gas-liquid separation. This embodiment includes a pipeline 19 , bypassing the I-SEP/Hi-SEP components 14 / 17 , directly to the first stage 12 controlled by a control valve 20 , such that the pre-separation stage is bypassed. The I-SEP/Hi-SEP arrangement can take part of the flow to debottleneck the main separator and also provide slug mitigation. [0038] FIG. 10 shows an example of making use of the I-SEP 14 for slug mitigation and a jet pump (SJP) 21 , located at the top of the riser 11 , upstream of the I-SEP 14 , that can be used to re-inject the separated gas flow 16 from the I-SEP 14 and re-inject this back into the main riser-pipeline this also enables mixing of the flow hence changing the flow regime. The outlet valves can be controlled by a slug detection system thus allowing flow diversion based on incoming slug style (part of which is described in our patent application WO2014006371). As illustrated, a bypass line is installed to bypass the I-SEP. Control valves are provided in the bypass line and upstream/downstream of the I-SEP. [0039] It is noteworthy that, for a slug mitigation application as required by the present invention, an I-SEP does not require control valves as no active control is needed, whereas the need for active control is needed in some prior art relating to slug mitigation. Furthermore, the I-SEP does not require a production separator immediately downstream in order to perform. [0040] The present invention seeks to find a system that mitigates a severe slugging regime in a passive way without the need of active control whilst imposing a smaller back pressure on the base of the riser (resulting in changing of the flow regime in the riser and increasing the stable flow region) this will result in a higher production for the operator. [0041] In one broad aspect of the invention there is provided a pipeline system including a riser located between a low level and an upper level of a pipeline, wherein an inline separator is located at the upper level of the pipeline, upstream of a first stage separator. A first control valve is located adjacent the inline separator, this may be either upstream or downstream thereof. In one embodiment, a gas line from the I-SEP is arranged to bypass the throttling valve.

A slug mitigation system for subsea pipelines includes a riser located between a low level and an upper (above sea-) level of a pipeline, where an inline separator, e.g. an “I-SEP”, is located upstream of a first stage separator. A throttling valve or fixed restriction is located downstream or upstream in series with the inline separator. Further aspects may also include a surface jet pump upstream of the in-line separator and/or a cyclonic separator downstream of the in-line separator.

You are an expert at summarizing long articles. Proceed to summarize the following text: [0001] This application claims priority based on co-pending U.S. application Ser. No. 60/569,093, filed May 7, 2004, inventor Radi Al Rashed, of same title. FIELD OF THE INVENTION [0002] The instant invention relates to low-viscosity, silicone-modified penetrating asphalt sealers, to methods of production thereof and to methods for using the sealers to treat and protect, in particular, heavy traffic asphalt pavement on a large scale against water-associated problems. BACKGROUND OF THE INVENTION [0000] Introduction [0003] Asphalt pavement, comprising asphalt coated particles bound by the asphalt, is known to be highly porous. The porosity exists in the form of pores connected through capillary channels formed in part during the compaction process. The pores and channels are affected by variations in aggregate size, and are formed in part because of an entrapment of solvent during the curing process. Fatigue caused by expansion and contraction due to heat variation also creates gaps between particles within a pavement matrix. These gaps may develop into cracks if not treated. The oxidation process of asphalt coated particles and the exposure to UV light are also known to cause further damage to bonds between asphalt and aggregate, which damage increases porosity as aggregates at the surface become loose. [0004] The presence of pores and capillaries allows water penetration, a phenomenon that causes additional damage to asphalt pavement. Water reduces the bonding strength between the asphalt and the gravel or any other material under the pavement. Water penetration allows the penetration of chloride ions from deicing salts, a chemical that attacks the asphalt matrix and shortens its life. In addition, freeze and thaw spalling and chipping becomes a problem in asphalt pavement in cold climates because of the fatigue and internal stress build-up due to the expansion of water upon freezing. [0000] More Particularly Asphalt and Water [0005] Water penetration through asphalt pavement may cause severe damage to the bonding strength between asphalt and aggregate. Water penetrates because of its unimpeded ability to move freely through capillaries and connected pores and voids. Typically, asphalt pavement is 13% to 20% voids. The typical aggregate to binder ratio is 10/1. [0006] Because of its ability to move freely through capillaries and connected pores and voids, water causes severe damage to asphalt pavement by several mechanisms. Water or moisture results in a breaking of the bonds between asphalt particles and aggregates. This in turn results in a weakening of the pavement and making it susceptible to problems that lead to a loss in strength and durability. Detachment, wherein a thin film of water results in the separation of an asphalt film from an aggregate surface without breaking the bond, has a high potential because of the ability of water to wet the aggregate surface more than the asphalt binder, due its lower surface tension. This phenomenon generally starts at the surface of the pavement and gradually moves downward as it develops to displacement, a condition where the asphalt film ruptures and the bonds between the asphalt and the aggregate break, which may appear in the form of loose aggregates. See references. [0007] Under wet conditions, repeated traffic and load applications result in the entrapment of water inside tiny pores. The entrapment leads to distress and continued buildup in pore pressure resulting in disrupting the asphalt film from the aggregate surface, which causes the formation of cracks. [0008] In cold climates, where repeated cycles of freezing and thawing occur, asphalt pavement with sufficient moisture is particularly susceptible to additional damage. When the temperature drops below the freezing point ice starts to form within the pores and capillaries of the pavement. Since water volume increases by 9% upon on freezing, if water is confined in the pores between freezing bodies and placed under compression, the pores may dilate causing an increase in the internal stress against the surrounding pavement particles. Repeated freeze and thaw cycles can result in the rupture and deterioration of the asphalt pavement due to fatigue stresses. Such deterioration may appear in the form of cracks and surface spalling. With time, fatigue stress can cause big chunks of the pavement to pop out. [0009] The penetration of water can be greatly influenced by the use of de-icing salts such as sodium chloride granules in cold climates. The concentration of such material within the pavements pores and voids increases with time. The result is an increase in the osmotic pressure, allowing more water to be absorbed under wet conditions at moderate temperatures. [0000] Oxidation of Asphalt [0010] The rate of oxidation of asphalt pavement is highly dependent on the voids in the total mixture. If the voids in the total mixture can be brought below 7-8% in-place, however, then the effect of oxidation will be greatly minimized. During the oxidation reaction, asphalt loses a significant amount of its saturate and aromatic components, which causes the asphalt mixture to stiffen at low temperatures, resulting in further crack formation. [0000] Current Art Techniques [0011] Maintenance of most asphalt pavements involves repairing localized problem areas, such as potholes or badly cracked pavement sections, and in sealing cracks. This type maintenance is needed to prolong the pavement life and to prevent rapid damage to the pavement due to water penetration and other causes. Some problems with asphalt pavement can be prevented or delayed by using good maintenance practices. Currently, there are three different maintenance methods commonly used: rejuvenators, slurry seals, and surface treatments. The choice between the methods mainly depends on the specific project to be maintained. [0012] Asphalt sealers currently available in the market are typically intended for use on low traffic asphalt pavement as a protective seal coat of a film-forming nature, which sealcoat acts as a “barrier coat” to protect the asphalt surface. There are two primary types: those made from refined coal tar and those made from asphalt. Refined coal tar—a by-product of the coking process—is complex mixture of thousands of chemicals and has different molecular structure in general from asphalt. The coal tar molecules have a predominantly closed ring (aromatic) structure with a minor degree of un-saturation. Because of their stable molecular structure, the destructive elements of weather and chemicals do not particularly affect the properties of coal tar. Sealcoatings based on a refined coal tar were introduced in the 1950s and until recently have been used extensively to protect off-street pavements. These sealcoatings often are referred to as C.T.P.E (Coal Tar Pitch Emulsions,) denoting that these coatings are water based, obtained by dispersing refined coal tar in a matrix of clay and water. In recent years, asphalt emulsion-based coatings have been introduced with varying degrees of success. In fact, many sealer manufacturers that previously produced only refined coal tar sealers now also produce asphalt-based sealers or even asphalt/refined coal tar blends. The asphalt emulsion based coatings deliver most of the same properties as refined coal tar-based coatings—except for a resistance to color fading due to ulrraviolet degradation and for a resistance to salts and petrochemicals like oils, fats, grease and solvents. These deficiencies are inherent in the asphalt binder itself. Being a petroleum derivative, asphalt has a natural affinity for petrochemicals, so it is easily dissolved by them. Asphalt emulsion-based coatings are made using either a soap emulsion (SS-1-H, for example) or a clay stabilizing emulsion. In recent years, asphalt sealer manufacturers have been quite successful in refining the performance of asphalt emulsion based sealers by using specialty chemicals and pigments. However, the asphalt emulsion-based coatings resistance to petrochemicals and solvents—while improved—has yet to be overcome. [0013] Silicone-based chemicals have been tested and used as additives to asphalt products to enhance the bonding properties between aggregates especially in cold applied patching and repair materials. Ward, Jr. (U.S. Pat. No. 4,373,960, U.S. Pat. No. 4,453,980, and U.S. Pat. No. 4,479,827) utilizes an organopolysiloxane material with non-emulsified asphalt to produce an asphalt-based binder that is to be mixed with pre-heated aggregates prior to application as a patching material for deteriorated pavements. In his inventions, the organopolysiloxane was at most 0.05% by weight, sufficient to enhance the products free flowing properties. [0014] A special blend of topped-coke-oven tar and aromatic solvent was introduced by McGoven (U.S. Pat. No. 4,661,378) as a penetrating sealer and rejuvenator for deteriorated asphalt pavements as well as for concrete surfaces. McGoven claimed that such material might penetrate up to 0.4 inch into asphalt pavement when applied on low-traffic pavement at a rate of 0.13 gallon/square yard. However, for heavy traffic asphalt pavement, such as roads, it had to be mixed with sand, pozzolana, or other fine mineral aggregates, which makes a slurry coat having more body than desired as in the case of conventional slurry-seal materials. A similar form of surface treatment consisting of an asphalt emulsion, diatomite, and sand that can be applied under ambient temperature using conventional paving machinery was invented by Kietzman (U.S. Pat. No. 4,548,650), where the filler diatomite to asphalt ration is in the range of 0.008 to 0.3 by weight. In addition to its overlay uses, Kietzman claimed that this material (with a little modification to improve its abrasion resistance, adhesion/cohesion, and tensile strength) could be used as a protection membrane for bridge decks and roads. [0015] In summary, conventional asphalt sealers currently available in the market have several defects. They are typically surface treatments. In addition to a lack of providing internal protection due to the high viscosity of the surface treatments, which does not allow them to penetrate, they may be considered a non-permanent treatment since they tend to wear-off the surface because of traffic. Because of their film-forming nature combined with their tendency to remain on the surface, these surface treatments cannot be used on roads and highways where slipperiness and skid resistance are of great concern unless they are broadcast with fine aggregates while wet or pre-mixed with fine aggregate in slurry form. This makes the treatment process itself less economical, due to the low coverage rate and frequent shut-down times. [0016] Sealing heavy-traffic asphalt pavements with a penetrating sealer, including an oxidized asphalt cutback that has been modified with a silicone-based compound that permanently provides internal as well as surface protection, to make a heavy-traffic asphalt pavement more durable, has never been taught, disclosed or practiced to applicant's knowledge, prior to the instant invention. There is a need for a new technology that more thoroughly addresses treatment problems for asphalt pavement in a cost-effective mater. SUMMARY OF THE INVENTION [0017] The present invention discloses a complex solvent-based mixture of several ingredients or active chemicals. The mixture was developed for the purpose of essentially eliminating water penetration into asphalt pavement from the surface, through utilizing a chemical repelling agent, as well as for the purpose of eliminating the transmission of water through the asphalt pavement while allowing vapor transmission (breathing). [0018] The invention is intended for the treatment and protection of heavy traffic asphalt pavement, such as found in bridges, highways, airport runways and taxiways, in a single application that results in an essentially maintenance free and worry free construction when it comes to water, oxidation, and UV problems. The invention should prolong the asphalt service life. [0019] In accordance with aspects of the present invention, there is provided a composition including a well-balanced mixture of ingredients or chemicals for achieving the above objective(s) and solving the above problem(s). Some of the ingredients or chemicals act independently while the rest work in conjunction with each other via chemical reactions to achieve the goal of the treatment. [0020] The chemical and physical functionality of ingredients or chemicals of preferred embodiments of the present invention can be summarized as: Petrochemically compatible surfactant (Preferably Nonylphenol polyethylene Glycol Ether:) behaves as a wetting agent to reduce the surface tension of the mixture and, thus, to allow the product to penetrate more deeply through capillaries of the pavement. Preferably an Antifoaming agent (such as isopropyl alcohol): reduces bubble formation and thus tends to eliminate air entrapment within the solution during manufacturing and application. Active Silicone Compound Providing a Water Repellent and Asphalt Reactant (preferably Methyltrimethoxysilane (CH 3 O) 3 SiCH 3 and/or Dimethyldimethyloxysilicone:) reacts with inherent water to form a siloxane resin which permanently adheres to the surface and inner surface of capillaries and voids, resulting in enlarged asphalt molecules and a significant increase in the surface tension of water, there by inhibiting water from penetrating through remaining capillaries. Fillers, to fill voids and pores of pavement (preferably a combination of very fine Graphite Powder and oxidized asphalt cutback). Fine graphite powder was found to be very effective (if having a mesh size less than 200) in sealing tiny voids, thus eliminating water from generating high pore pressure under wet conditions. More importantly a highly oxidized asphalt cutback (19K from Lion Oil) was found to be a most suitable filler and oxidized asphalt for this invention. Petroleum-based solvent as a carrier preferably a Stoddard solvent. [0026] The present invention is recommended for the treatment and protection of large-scale heavy traffic asphalt pavement, mainly bridges, asphalt highways, airport runways, taxiways, and parking garages. Application of the invention is preferably through a spraying and a mechanical brushing mechanism, the spraying mechanism being adequate to spray large areas in a short period of time. The recommended coverage of the invention is 100 to 110 ft 2 /gallon in a single one-time application. The application may not require more than 1 hour of closure time, since the very low viscosity of mixture allows it to penetrate very quickly leaving only traces at the surface. BRIEF DESCRIPTION OF THE DRAWINGS [0027] A better understanding of the present invention can be obtained when the following detailed description of the preferred embodiments are considered in conjunction with the following drawings, in which: [0028] FIGS. 1 and 1 A illustrate the invention's performance; [0029] FIG. 2 illustrates application techniques; [0030] FIGS. 3A, 3B and 4 illustrate an application machine. [0031] The drawings are primarily illustrative. It would be understood that structure may have been simplified and details omitted in order to convey certain aspects of the invention. Scale may be sacrificed to clarity. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0032] It has been discovered that an oxidized asphalt cutback provides an excellent filler for an asphalt pavement sealer and treatment material. Preferably the oxidized asphalt cutback is combined with a fine graphite powder to form an emulsion that can lead to a significant reduction in the porosity of asphalt pavement by partially filling the voids and pores of the pavement. When coupled with a formed siloxane resin, the mixture results in strengthening of the adhesion between the existing asphalt material and aggregate as well as between any oxidized bitumen particles, functioning as a substitute for lost aromatic compounds of the pavement. The mixture tends to eliminate further oxidation of the asphalt material. As a result of partially sealing voids and capillaries, some moisture transmission is eliminated. Embodiments of the invention can act as a further moisture barrier by coating the surface of exposed aggregate, preventing moisture from being absorbed therein, especially in the case of limestone aggregate, which is commonly used in asphalt pavements. [0033] A further preferred aspect of the present invention includes an active silicone compound providing a solvent soluble water repellant and asphalt reactant. Preferrably the silicone compound includes Methyltrimethoxysilane (CH 3 O) 3 SiCH 3 ), and/or Dimethyldimethyloxysilane. Methyltrimethoxysilane and Dimethyldimethyloxysilane are chemical monomers that slowly react with water in the pavement and atmosphere to form an invisible film of siloxane resin which permanently adheres to the surface and inner surface of capillaries and voids. Under wet conditions, the siloxane resin functions as a water repellant by significantly increasing the surface tension of water to such a degree that it is essentially impossible for water to penetrate through remaining capillaries of a treated asphalt pavement. As a result, the siloxane resin maintains a dry surface that effectively resists the damage typically caused by freezes and thaws. [0034] The performance of the protection process for preferred embodiments of the present invention is believed to be enhanced by the presence of Nonylphenol polyethylene Glycol Ether as a petrochemically compatible surfactant, by virtue of which the viscosity of the chemical mire can be reduced to about 12% of that of the asphalt cutback itself at room temperature. [0035] Embodiments of the current invention have been tested by Construction Technology Laboratories, Inc. (CTL) to investigate their effect on skid resistance, using two different standard methods. First, the ASTM E303-93 “Standard Test Method for Measuring Surface Frictional Properties Using the British Pendulum Tester” measures the “British Pendulum Number (BPN).” Secondly, the ASTM F609 “Standard Test Method for Static Slip Resistance of Footwear, Sole, Heel, or Related Materials by Horizontal Pull Slip Meter (HPS)” measures the friction coefficient. A sample of the invention was applied to three different areas on an existing asphalt pavement. The tests were performed on those areas as well as on three different areas that were left untreated as controls. Results of both tests indicate that the areas treated with the current invention had British Pendulum Numbers and coefficients of friction comparable to those results obtained from the tests on untreated areas. [0036] A preferred embodiment of a present invention is formulated by combining six different chemicals in a liquid form. To our knowledge, an optimum quantitative chemical composition of the invention can be achieved if the mixture is prepared using the data given in Table 1 on a weight basis. Such a composition will provide a solution of about 55% solids content that has a very low viscosity of 90 centipoises at 77° F. to assure deep penetration. TABLE 1 Optimum chemical composition of the invention. Chemical Name wt. % Graphite Powder (<200 mesh) 4.055 Oxidized Asphalt Cutback (60% Solids) 85.230 Isopropyl Alcohol (Anhydrous) 2.033 Nonylphenol Polyethylene Glycol Ether (pure) 0.045 Methyltrimethoxysilane (CH 3 O) 3 SiCH 3 ) 4.572 Stoddard solvent 4.065 Total 100 [0037] Altering the chemical composition of the above invention by adjusting the weight percentages of one or more of the chemical ingredients, to a certain degree, will not have a great effect on the overall performance of the invention, especially as long as the method of application is adjusted accordingly. For instance, a reduction in the solids content would result in a diluted form of the invention. In such case, the material should be applied to the asphalt pavement at a higher rate. [0038] The overall performance of the invention in treating heavy traffic asphalt pavements should be acceptable if the content of the chemicals remain within the ranges given in Table 2. TABLE 2 Minimum and maximum weight percentage of chemicals through which the invention will remain effective. Minimum Maximum Chemical Name wt. % wt. % Graphite Powder (<200 mesh) 0.000 8.000 Oxidized Asphalt/Cutback Emulsion (60% Solids) 75.000 90.000 Isopropyl Alcohol (Anhydrous) 0.500 3.500 Nonylphenol Polyethylene Glycol Ether (pure) 0.001 0.200 Methyltrimethoxysilane (CH 3 O) 3 SiCH 3 ) 3.000 6.000 Stoddard solvent 2.000 8.000 [0039] Preferred production processes for the present invention utilize a multi step mixing of the chemicals to minimize interactions that may cause the material to coagulate during manufacturing. For this purpose, a reactor vessel with a high-speed sheer mixer is preferably utilized to maintain the product in an emulsion form, thus minimizing the settling of solid particles. [0040] Although, the invention may also be produced in fewer steps, with certain precautions, to our best knowledge the chemicals are preferably mixed in three different stages for the preferred embodiment. The product of the first stage is called the “Base Emulsion”. The product of the second stage is called the “Catalyst”. Both the “Base Emulsion” and the “Catalyst” are considered as intermediate products for the purpose making the finished product. [0041] Disclosed below is a preferred procedure as well as, to our knowledge, the best chemical composition for making the preferred embodiment of the invention in its ready-to-use form. [0000] Stare One: Making of the “Base Emulsion” [0042] Batch size=1000 US Gallons, Net weight=7818.9 LB TABLE 3 Materials required for the manufacturing of a 1000 gallons of Base Emulsion Chemical Weight (LB) Oxidized Asphalt Cutback (60% Solids) 7463.8 Graphite Powder (<200 mesh) 355.1 Total Weight 7818.9 Mixing Procedure [0043] 1. Place the asphalt cutback in the mixing vessel and start the mixer at a medium speed. [0044] 2. Add the graphite powder gradually. Do not add more than 20% at a time. [0045] 3. Increase the mixing speed to about 1500 rpm and mix for 10 minutes before adding the next portion of the graphite powder. [0046] 4. Repeat steps 2 and 3 until all the graphite powder is consumed and continue mixing for 30 minutes. [0047] 5. Cover the mixing vessel and allow the material to cool to room temperature and settle for 24 hours before using in the production of the concentrate. [0000] Stage Two: Making of the “Catalyst” [0048] Batch size=1000 US Gallons, Net weight=7449.7 LB TABLE 4 Materials required for the manufacturing of a 1000 gallons of the Catalyst Chemical Weight (LB) Stoddard solvent 2826.2 Isopropyl Alcohol (Anhydrous) 1413.5 Nonylphenol Polyethylene Glycol Ether (pure) 31.3 Methyltrimethoxysilane (CH 3 O) 3 SiCH 3 ) 3178.7 Total Weight 7449.7 Mixing Procedure [0049] 1. Place all the Stoddard solvent in the reactor and start the mixer at a low speed. [0050] 2. Gradually add the Isopropyl Alcohol and mix for about 10 minutes. [0051] 3. Add the Nonylphenol Polyethylene Glycol Ether and mix for 10 minutes. [0052] 4. Gradually add the Methyltrimethoxysilane and continue mixing for an additional 15 minutes. [0000] Stage Three: Making of the “Finished Product” [0053] Batch size=1000 US Gallons, Net weight=7777.6 LB TABLE 5 Materials required for the manufacturing of a 1000 gallons of a Preferred Embodiment of the Invention in its ready-to-use form. Chemical Weight (LB) Base Emulsion 6944.20 Catalyst 833.37 Total 7777.57 Mixing Procedure [0054] 1. Place the exact amount of the Base Emulsion in the mixing vessel and start mixing a medium speed. [0055] 2. Weight the exact amount of the catalyst in a separate container then add it in three steps to the mixing vessel. Allow at least 5 minutes of mixing between portions. [0056] 3. Increase the mixing speed gradually to 1500 rpm, and mix for 10 minutes. [0057] 4. Repack in 5-gallon pails or 55-gallon drums and seal well. [0000] Method Of Application [0058] To our best knowledge, the preferred embodiment of the invention should be applied at a coverage rate of 1 gallon per 100-110 square feet. The preferred method of application, such that the invention can effectively penetrate into the asphalt pavement, would be as follows: [0000] Heavy-Traffic Areas [0059] For heavy-traffic asphalt pavement, such as roads, bridges, and highways, the material is best mechanically brushed at the surface, in order to prevent it from accumulating at the surface, especially between surface aggregates. Brushing tends to eliminate the forming of small pools, hence maintaining the slip-resistance of the surface ( FIG. 2 ). [0060] An application machine has been specially designed for this purpose, by which machine a preferred embodiment of invention is sprayed at the surface of the pavement and then forced inside the pavement by a cylindrical brush rotating at a high speed (see below.) [0061] For the invention to effectively penetrate into the pavement, the surface is preferably first cleaned and freed from any contaminants that might block the material from penetrating through the surface openings. The pavement may be cleaned using the same mechanical brushing system in a single pass prior to applying the invention to the surface. [0000] Low-Traffic Areas [0062] For low-traffic asphalt pavement, such as parking garages, sidewalks and driveways, the material can be applied by either spraying or rolling. However, it is preferable that the surface be cleaned first, and dry. Cleaning can be achieved by using high-pressure compressed air, for instance, which removes dust, loose particles and other contaminants that might prevent the invention from penetrating. [0000] Application Machine [0063] An application machine of a trailer type ( FIG. 3 ) has been specifically designed for the purpose of applying preferred embodiments of the invention on heavy-traffic asphalt pavement, where it efficiently forces more material into the pavement and eliminates accumulation at the surface. It comprises essentially a computerized spraying mechanism and a mechanical brushing system powered hydraulically by a gasoline engine. [0064] As part of the spraying mechanism, a radar sensor is installed to measure speed. The sensor sends a signal to a programmable controller that adjusts the flow rate of the material via a sinusoidal valve as a function of the vehicle speed (2-9 miles/hour), thus maintaining a desired coverage rate through an 8-feet wide spraying bar that uniformly sprays the material through nine evenly spaced nozzles. [0065] The brushing system is hydraulically driven and equipped with a hydraulic load-control to enhance the penetration process by applying pressure at the surface. While rotating at high speed (100-500 rpm) in the opposite direction to the wheels, the bristles of the rotary brush continuously sweep any excess material between surface aggregates and evenly distribute it at the surface. [0066] As a maintenance measure, a flushing system can be added to the machine in order to clean the spraying mechanism (pump, valves, and pipes) from any residue after each application, thus preventing clogging. A detailed schematic diagram of the application is illustrated in FIG. 4 . [0067] In preferred embodiments of the present invention, these active ingredients and chemicals are combined together through a multi-stage manufacturing process to produce a unique product that is able to solve water-associated problems in asphalt pavement permanently by a double action technique that maintains the pavement essentially internally dry. Although the present invention is of a penetrating nature, its water repelling efficiency exceeds the established federal specifications. Its internal waterproofing technology is superior because it waterproofs internally as well as at the surface. [0068] Once fully cured, the present invention maintains a uniform black color across treated pavement with a non-shine (matt) look that tends to eliminate reflection of sunlight during the day or headlights at night. [0069] The foregoing description of preferred embodiments of the invention is presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention to the precise form or embodiment disclosed. The description was selected to best explain the principles of the invention and their practical application to enable others skilled in the art to best utilize the invention in various embodiments. Various modifications as are best suited to the particular use are contemplated. It is intended that the scope of the invention is not to be limited by the specification, but to be defined by the claims set forth below. Since the foregoing disclosure and description of the invention are illustrative and explanatory thereof, various changes in the size, shape, and materials, as well as in the details of the illustrated device may be made without departing from the spirit of the invention. The invention is claimed using terminology that depends upon a historic presumption that recitation of a single element covers one or more, and recitation of two elements covers two or more, and the like. Also, the drawings and illustration herein have not necessarily been produced to scale. REFERENCES [0070] 1 Majidzadeh, K. and Brovold, F. N., “ Sate of the Art: Effect of Water on Bitumen - Aggregates, ” Special Report 98, HRB, National Research Council, Washington, D.D. (1968) [0071] 2 Fromm, H. J., “ The Mechanisms of Asphalt Stripping from Aggregate Surfaces, ” Proc., Association of Asphalt Paving Technologists, Vol. 43, pp. 191-223 (1974) [0072] 3 Bhairampally, R. K., Lytton, R. L., and Little, D. N., “ Numerical and Graphical Method to Assess Permanent Deformation Potential for Repeated Compressive Loading of Asphalt Mixtures, ” Journal of the Transportation Board, No. 1723, National Research Council, Washington, D.C. (2000) [0073] 4 Mack, C. “Bituminous Materials,” Vol. 1, Interscience Publishers, New York (1964)

A solvent-based solution including methods of making and using for treating and protecting for heavy traffic asphalt pavement, particularly against water-associated problems, such as repeated freeze/thaw cycles, and damage caused by exposure to UV light. The mechanism of protection include an internal coating and partial internal sealing of voids and pores with a special blend of pre-oxidized asphalt emulsion that has been modified with moisture-insensitive silicone-based compounds and surfactants to enhance penetration depth and effectiveness. The sealer works from within the asphalt pavement as well as at the surface. A water-repelling function prevents water from penetrating from the surface while allowing vapor transmission across the pavement through connected voids and capillaries. The sealer should also enhance the bonding strength between asphalt coated particles, thus eliminate chipping. As a result, the sealer should prolong the life of exiting and of new asphalt pavement as well as reduce maintenance cost.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION The present invention relates to a rock bolt and, particularly, but not exclusively, to a self-drilling rock bolt which may be used in mining applications. BACKGROUND OF THE INVENTION Rock bolts for supporting structures e.g. roofs of passageways in mines are well known. There are many different types of rock bolts. A rock bolt generally consists of an elongate shank (length will generally depend upon the material which the rock bolt is intended to secure) having a distal end (the end which in use is fixed furthest within the rock), and a proximal end (the end, in use, which is closest to the surface of a rock and, in many cases, may actually project from the rock surface), or “tail end”. Rock bolts are fixed in elongate boreholes (not much wider than the rock bolt) which is drilled in the rock. In use, a bearing plate is secured at the tail end of the rock bolt fast against the rock surface. The rock bolt and bearing plate assembly operate to support the rock. Many rock bolts may be used to support structures. For example, in mines rock bolts may be used to support passageways. Installation usually requires drilling of the borehole by using a drill rig and a drill steel (a long steel rod with a drill bit on the end). The drill steel is then removed from the borehole. Resin (or “grout”) is inserted into the borehole, then the rock bolt itself is inserted and tightened up against the bearing plate. Some rock bolts incorporate point anchoring mechanisms, which can be manipulated post insertion of the rock bolt to mechanically interfere with walls of the borehole in order to firmly secure the rock bolt. The conventional procedure for installing rock bolts involves drilling a bore hole using a drill steel, removing the drill steel, inserting resin and a rock bolt and securing the rock bolt. “Self drilling” rock bolts are also known. These generally incorporate a drill bit as part of or connected to the distal end of the rock bolt, a tail end being attachable to a drill rig in order to drill the bore hole with the rock bolt. Once the hole is drilled, the rock bolt is retained in the hole. One such self drilling rock bolt is disclosed in the Applicant's co-pending Australian patent application number 2006903922, entitled “Rock Bolt” and filed on 20 Jul. 2006. The disclosure of this provisional patent application is incorporated herein by reference. This earlier application discloses a self drilling rock bolt which includes a point anchoring mechanism. Rock bolts are required to be high strength, typically over 30 tonnes ultimate tensile strength. Rock bolts are typically bonded to the borehole walls by resin. It is advantageous for the surface of the rock bolt to be deformed in order to provide high bond strength between the bolt/resin/rock interfaces. Self drilling rock bolts have typically been rebars (strong steel bars) having an axially extending central path for water passage (and post grouting). The cost of making such hollow steel bars is quite high, and is uneconomical for high density rock support required by many underground mines. It has been proposed to use a solid rebar with an outer sleeve for water passage during drilling. The outer sleeve, however, typically reduces the bonding between the rebar and the bore hole wall. It has also been proposed to use high strength pipe which has limited surface deformations, if any, and is expensive and difficult to manufacture in the required high strength material. SUMMARY OF THE INVENTION In accordance with a first aspect, the present invention provides a rock bolt, comprising a shank portion comprising a hollow tubular member and a reinforcing arrangement in use operating to reinforce the hollow tubular member. In an embodiment, the reinforcing arrangement also provides deformations in an outer surface, whereby to improve bonding in a rock bolt borehole. In an embodiment, the reinforcing arrangement comprises a reinforcing material mounted about a wall of the hollow tubular member. In an embodiment, the reinforcing material is mounted about an outer wall of the hollow tubular member. In an embodiment, the reinforcing arrangement is strand wrapped around an outer wall of the hollow tubular member. In an embodiment, the strand is metal strand and, in an embodiment, is “prestressed concrete” (PC) type steel strand. In an embodiment, the strand itself may be “spiral type” PC wire, which advantageously adds further deformation on a smaller scale to the already deformed outer surface formed by the strands. In an embodiment, the strand may be indented in order to provide extra deformation. In an embodiment, where the reinforcing arrangement comprises metal strand, the metal strand may be secured at an end of the hollow tubular member by a securing member arranged to receive ends of the metal strand and secure them to the hollow tubular member. In an embodiment, the securing member is a nut having a threaded portion arranged to seat on a corresponding threaded portion on the hollow tubular member, and comprising passageways for receiving ends of the metal strand. In manufacture, the nut may be rotated on the threaded portion to rotate the metal strand into position around the hollow tubular member and secure it to the hollow tubular member. A nut may be provided at each end of the shank portion for this purpose. In an embodiment, a wedge mechanism may be arranged to secure the metal strand. The shank (which, in an embodiment, forms the majority of the length of the rock bolt) is, in an embodiment, formed of hollow pipe, which may be commercially available. In an alternative embodiment, the pipe may not be the standard diameter and is specially made. Using rigid hollow pipe made by conventional high volume methods and metal strand reinforcement members in accordance with an embodiment of the present invention, has the advantage that it is typically less expensive than hollow rebar yet strong enough to achieve similar or even much higher tensile strength than currently used for primary rock support. In an embodiment, the hollow pipe may be of mild steel (10-22 mm diameter), being rigid and strong enough to drill the single hole. When the rock bolt is subsequently secured to the borehole walls by either resin or mechanical anchor, the reinforcement arrangement can be tensioned which provides additional rock reinforcement by means of pre-stressing the rock mass. Where the reinforcing arrangement is a metal strand, up to 95% and perhaps even more of the load may be carried by the strand. In an embodiment, the rock bolt may be a self drilling rock bolt including the shank, a distal end at one end of the shank and a tail end at the other end of the shank. The rock bolt may incorporate a point anchoring mechanism, such as described in the Applicant's co-pending application referenced above. BRIEF DESCRIPTION OF THE DRAWINGS Features and advantages of the present invention will become apparent from the following description of embodiments thereof, by way of example only, with reference to the accompanying drawings, in which: FIG. 1 is a side view of a rock bolt in accordance with an embodiment of the present invention; FIG. 2A is a cross-section through a securing arrangement of the embodiment of FIG. 1 ; FIG. 2B is a plan view showing an inner surface of a securing insert of the securing arrangement of FIG. 2A ; FIG. 3 is a side view of a rock bolt in accordance with a further embodiment of the present invention; FIG. 4 is an end view from one end of the rock bolt of FIG. 3 ; FIGS. 5A , 5 B and 5 C are details of an alternative securing member for use with an embodiment of the present invention; FIG. 6 is a detail of a distal end of the rock bolt of the embodiment of FIG. 3 ; FIG. 7 is a cross-section on line XX of FIG. 6 ; FIG. 8 is a side view of a rock bolt in accordance with yet a further embodiment of the present invention; FIG. 9 is a view from one end of the rock bolt of FIG. 8 ; FIG. 10 is a detailed exploded view of a reinforcing member of the embodiment of FIG. 8 ; FIG. 11A is a side view of a rock bolt in accordance with yet a further embodiment of the present invention; FIG. 11B is a detailed exploded view of a part of the rock bolt of the embodiment of FIG. 11A ; FIG. 12 is a side view of a portion of a rock bolt in accordance with an embodiment of the present invention; FIG. 13 is a cross-section through the shank of a rock bolt in accordance with an embodiment of the present invention; and FIG. 14 is a cross-section through a shank of a rock bolt in accordance with a further embodiment of the present invention. DETAILED DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will now be described with reference to FIG. 1 . A rock bolt, generally designated by reference numeral 1 comprises a shank 2 . The shank 2 , in this embodiment, is comprised of a hollow tubular member 5 and a reinforcing arrangement 4 . In this embodiment, the hollow tubular member 5 has a longitudinally extending passageway 3 which extends the length of the shank 2 . In this embodiment, the hollow tubular member 5 is a hollow tube formed from rigid hollow pipe. The reinforcing arrangement 4 , is of high strength and forms a deformed outer surface which provides high load transfer through the cementitious grout/resin which is placed between the strands and borehole wall. In this particular example, the reinforcement arrangement is in the form of reinforcing strand which is wound around the outside of the hollow tube 5 . In this embodiment, the strands 4 are high tensile “PC” steel strand wound about the outside of the hollow tubular member 5 . The strand is welded to the hollow tubular member 5 at a distal end 6 of the rock bolt 1 . The deformations in the outer surface are formed by the nature of the strands, not being a smooth outer surface. As well as the nature of the wound strands providing deformed surface, additional deformation may be added by indenting the strands or using “spiral type” PC wire. In more detail, the rock bolt 1 also includes, at the distal end 6 , a drill bit 8 mounted on the tubular member 5 to enable self drilling of the rock bolt 1 . In order to secure together the reinforcing strands 6 , for purpose of tensioning and load bearing, a securing arrangement 9 is arranged at the tail end 7 of the rock bolt 1 . The securing arrangement 9 includes a cylinder 10 incorporating a wedge arrangement in the interior of the cylinder. The cylinder and wedge are mounted about the outer surface of strand 6 and the cylinder is then deformed onto the wedge so that the wedge bites into the strand 6 to provide further securing. The hollow tubular member provides the radial resistance to maintain the strands in position against the wedge compressing radially inwards. The securing arrangement 9 is shown in more detail in FIGS. 2A and 2B . Within the cylinder 10 there are mounted three inserts 12 , which, in this embodiment, are not “wedge” shaped as such but part cylindrical sections. FIG. 2B shows a front on plan view of an inside face of one of the inserts 12 . In use, the inside face 12 butts against the strand 6 . The inside face 12 is provided with a plurality of serrations or teeth 13 . Alternatively, this may be in the form of a thread 13 . When the cylinder 10 is compressed over the inserts 12 the serrations/teeth 13 penetrate or otherwise interfere with the strand 6 to secure the strand 6 . The compression is carried out by machine operation during manufacture of the rock bolt 1 . This is a swage type of end fitting. Once the cylinder 10 has been compressed about the inserts 12 , an outer thread is formed on the outside of the cylinder 10 , for receiving retention nut 11 . As an alternative to the part cylindrical inserts, wedge shaped inserts could be used. The outer surface of the cylinder has a thread formed on it to receive a cooperatively threaded tension nut 11 . In operation, the tension nut 11 may be tensioned against a mounting plate (not shown) hard up against the rock face when the rock bolt is in place. To install the rock bolt, the tail end 7 of the shank 2 is placed into a rock drilling motor. A drill rig rotates the rock bolt 1 and the drill bit 8 drills into the rock. As drilling proceeds, water or other cooling fluid may be provided via the central passageway 3 . The whole tubular member provides sufficient strength to provide for rotation/impact of the drilling bit into the rock. When the rock bolt is into the rock at sufficient depth, cementitions grout/resin is injected into the hollow tube to flow out of the drill bit and down the bolt between the borehole wall and reinforcing strand. Alternatively, grout can be pumped upwards between the borehole and the outer circumference of the rock bolt 1 . The passageway 3 in this case is used as a breather tube to allow air to escape as grout fills the voids. The grout is allowed to cure and secure the reinforcing strand to the rock. The tension nut is then rotated hard up against the mounting plate in order to tension the bolt and plate against the rock face. The reinforcing strand, when bonded to the borehole wall with resin, acts to provide the rock reinforcement. This is achieved through having an overall deformed surface/circumference to bond to the rock and the required very high strength to carry the load transferred to the reinforcing member through rock movement. A further embodiment will now be described with reference to FIGS. 3 and 4 . The same reference numerals have been used in these figures to identify similar features of this rock bolt to the rock bolt of FIG. 1 and no further description will be given of these features. In this embodiment, the rock bolt 20 comprises an alternative securing member to secure the reinforcement arrangement 4 . In more detail, a securing member arranged at the tail end 7 of the rock bolt 20 comprises drive nut 21 . The drive nut 21 is fixed to the hollow tubular member 2 by way of a thread on the inside of the drive nut 21 and outside of a portion of tubular member 5 . The drive nut 21 also includes a number of bores 23 for receiving strands 4 of the reinforcing arrangement. The strands have a button head 26 formed onto the ends for securing against the bores 23 . A reinforcing nut 24 at the distal end 6 of the rock bolt 20 is arranged for mounting on a threaded portion 25 of the distal end 6 . In manufacture, when the drive nut 21 is twisted in a clockwise direction, it will cause winding on the originally straight strands 4 to form a helically twisted formation. In operation, when the rock bolt 20 has been drilled into the bore hole, grouting may then be carried out via the central passageway 3 as usual. In this embodiment, “button distals” 26 may be formed at the ends of the reinforcing strands 4 , to secure the strands within the passageways 23 in drive nut 21 (and also in the securing nut 24 ). A variation on the securing member for securing the reinforcement arrangement 4 is illustrated in FIGS. 5A , 5 B and 5 C. In this alternative, the securing member is in two parts. One part comprises a cylindrical end block 22 which includes circumferential bores 23 for receiving the ends of reinforcing strand 4 . The end block 22 may be secured to the hollow tubular member 5 by welding or threads on its inner surface 27 . Referring to FIG. 5A , reference numeral 26 clearly indicates a forged button on the end of each individual wire of the strand 4 . The button-end 26 is formed after the wires are inserted through the passageways 23 in the end block 23 . The other part of the securing member comprises a tensioning nut 28 , which includes a nut 28 having a cylindrical recess 29 which is arranged to receive the end block 22 to seat therein, as best illustrated in FIG. 5C . The tensioning nut also includes a passageway 35 which extends around the outside of the strand 4 . A thread may be provided at this portion of the strand 4 to engage with a corresponding thread on the inside of the passageway 35 . In operation, the rock bolt 20 is drilled into the rock. After grouting, the tensioning nut 29 may then be rotated up against a mounting plate (not shown) to post-tension the rock bolt 20 . In the alternative using the securing member 21 , no post-tensioning is required and drilling occurs until the securing member 21 is drilled up against the rock or a mounting plate (not shown), and then grouting is introduced into the bore hole. FIG. 6 shows a detail of the distil end 6 of the rock bolt of FIG. 3 . The securing nut 24 has bores 36 for receiving reinforcing strand 4 . No button heads are required on the strand for this end. The nut 24 and strand 4 could be welded to the tubular member 5 if required. As this end 6 of the bolt 20 is grouted within the rock, less strength is required than at the proximal end 7 of the rock bolt 20 . A further embodiment will now be described with reference to FIGS. 8 , 9 and 10 . Again, the same reference numerals have been used to denote features which are the same as already described for previous embodiments, and no further description will be given of these features. In the rock bolt 30 of this embodiment, an alternative securing arrangement 31 is utilised to assist in securing the reinforcement strands 4 and tensioning the rock bolt 30 . A reinforcing member 31 includes a tapered internal surface 33 and wedges 32 that are arranged to slide against the tapered internal surface 33 . In operation, the member 31 is tensioned against a mounting plate when the rock bolt 30 is in place within the bore hole. Upon subsequent loading as the member 31 is pulled up against the mounting plate, it forces the wedges to bite into the strands 4 and secure the strands 4 . In the embodiment of FIGS. 8 and 9 , there are three wedges 32 . An exploded view of the barrel 31 and wedge 32 arrangement is shown in FIG. 10 . Again, although not clearly shown in FIG. 10 , there are 3 wedges 32 . It will be appreciated that there may be more or less wedges. In operation, the rock bolt 30 is drilled into the rock up until the mounting plate and barrel are tensioned against the rock surface and the barrel 31 is forced backwardly over the wedges 32 to secure the strands 4 . Grouting is then implemented. FIG. 12 shows a portion of the embodiment of FIG. 8 , showing a mounting plate 39 in section. The barrel 31 seats in a hole or recess 38 in the mounting plate 39 . Yet a further embodiment is illustrated in FIGS. 11A and 11B . The rock bolt 40 of FIG. 11 a includes a mechanical anchoring arrangement, generally designated by reference numeral 45 , at the distal end 6 of the rock bolt 40 . The mechanical anchoring arrangement 45 is of similar construction to the mechanical anchoring arrangement disclosed in Australian provisional patent application number 2006903922, referenced above. The mechanical anchoring arrangement 45 operates to point anchor the rock bolt 40 . The mechanical anchoring arrangement 45 will now be described in more detail. Towards the distal end 6 of the rock bolt 40 , the tubular member 5 is threaded with screw threads 49 . The threaded portion 49 extends up to the drill bit 8 . The drill bit 8 comprises a base forming a stop 50 where the threaded portion 49 meets the drill bit 8 . The mechanical anchoring arrangement 45 includes an expansion shell 47 and chuck 46 . The expansion shell 47 in this example, has longitudinally extending leaves 52 , 53 (note only two are shown in the drawings but there are three leaves). Note that the number of leaves on the expansion shell 47 could vary. For example, the leaves could vary from two to four. The leaves 52 , 53 are arranged to move outwardly on expansion of the expansion shell 47 and are formed with a plurality of external protrusions 54 which assist in gripping the sides of the borehole to secure the rock bolt 40 in place. The expansion shell 47 also includes a bore 55 for sliding engagement with the threaded portion 49 . An abutment member in the form of a threaded nut 56 is mounted on the threaded portion 49 and operates to prevent the expansion shell 47 from sliding further towards the tail end 7 . The chuck 46 has a threaded bore (not shown) for threaded engagement with the threaded portion 49 . Rotation of the rock bolt 40 relative to the chuck 46 thus causes axial motion of the chuck 46 along the threaded portion 49 . The chuck 46 includes tapered surfaces in sliding keying engagement with complementary surfaces on the extension leaves 52 , 53 , such that axial motion of the chuck 46 towards the tail end 7 relative to the expansion shell 47 will cause the leaves 52 , 53 to diverge outwardly and grip the walls of the borehole. The chuck also includes projections 57 which extend into slots 58 formed between the leaves 52 , 53 and prevent relative rotation of the chuck 46 and expansion shell 47 with respect to each other. Stop 50 formed by the base of the drill bit 8 prevents chuck 46 and expansion shell 47 from moving over the distal end of the rock bolt 40 . The protrusions 54 are in a spiral formation, to assist with the flow of fluid during drilling, and aid in clearance of filings/cuttings. The spiral runs in the opposite direction to the thread form i.e. right hand spiral for left hand thread. Installation of the rock bolt 40 will now be described. A drill rig and spanner is attached to the rock bolt. Drilling into the rock substrate is implemented by rotating the rock bolt in the clockwise direction (in this embodiment). It will be appreciated that a reverse threaded arrangement may be rotated in the anticlockwise direction. As drilling proceeds, the expansion shell 47 may resist rotation as it abuts the walls of the borehole, and this will result in relative anticlockwise rotation of the expansion shell 47 and chuck 46 relative to the rock bolt 40 . This will cause the chuck 46 to travel along the threaded portion 49 towards the distal end of the rock bolt 40 where it will abut the flat 50 . Once flat 50 is engaged by the chuck 46 then the expansion shell 47 and chuck 46 will continue to rotate in the drilling direction with the rock bolt 40 . Once the rock bolt 40 has created a borehole of the desired length, drilling in the forward direction is ceased and rotation in the reverse direction (anticlockwise in this embodiment) is applied by the drill rig. By virtue of the anticlockwise motion of the threaded portion 49 , the chuck 46 will now move towards the tail end 7 . As the chuck 46 moves along the threaded portion 49 , the tapered surfaces in sliding keying engagement with the complementary surfaces on the extension leaves 52 , 53 , cause the expansion shell 47 to expand outwardly. The protrusions 54 on the external surfaces of the leaves 52 , 53 engage the walls of the borehole and mechanically secure the rock bolt 40 in place and provide tension to the reinforcement member. Grouting the rock bolt 40 can then be carried out as discussed with reference to the previous embodiments. FIG. 11B shows a exploded view of the head end of the rock bolt 40 of FIG. 11A , more clearly showing the components of the point anchoring mechanism. The tail end of the rock bolt 40 may have any securing arrangement. In FIG. 11A , the securing arrangement comprises a barrel 31 and wedge 32 assembly as shown. FIGS. 13 and 14 show cross sections through the shanks of rock bolts in accordance with embodiments of the present invention. These diagrams illustrate that different widths of reinforcing strands and different dimensions of tubular member may be utilised. In FIG. 13 , for example, strands 4 may be 6 mm in diameter and the internal diameter of the tube 5 is 12 mm. Relatively large particle grout can be used with increasing hollow tube internal diameter. The arrangement of FIG. 14 , on the other hand, has smaller diameter strands 4 (5.5 mm) and a smaller diameter tube 5 (12.7 mm), for possible resin injection. The rock bolt of the present invention is not limited to the dimensions shown in FIGS. 13 and 14 . These are example dimensions only. In the above embodiments, the reinforcing arrangement is formed by strands of strong material (such as steel). Other materials then steel may be used for the strands. Further, the reinforcing arrangement may comprise other forms than strands. For example, a webbing of strong material may form the reinforcing arrangement. All the above embodiments relate to self drilling rock bolts. The present invention is not limited to self drilling rock bolts. A conventional rock bolt with a hollow tube and reinforcing arrangement also falls within the scope of the present invention. In the above embodiments, various arrangements are illustrated and described for securing the reinforcing arrangement at the head and tail of the rock bolt. Other arrangements than described may be utilised. For example, in a simple embodiment, the strand may be welded at the head end and also welded at the tail end. In the above embodiments, the reinforcing arrangement comprises reinforcing strands of a metal material, such as PC Steel. The reinforcing arrangement may be of other material. For example, it may comprise fibreglass or plastics. It may comprise fibreglass or plastics strand. Any other suitable material may be used. In the above embodiments, the tubular members of hollow steel pipe or other metal material. It may be of any other suitable material, such as fibreglass, for example. In embodiments of the invention, there is the advantage that the tubular member holds the initial tension and then the reinforcing arrangement, in examples being reinforcing strand, takes over the load when the rock bolt is secured in the bore e.g. by grouting. In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

The present invention relates to a self drilling rock bolt which may be used in mining applications. Self drilling rock bolts are typically formed by rebars having an axially extending central passageway for water passage and post grouting. Costs of such hollow steel rebars is quite high. In the present invention, a rock bolt is formed from a hollow tubular member which may be steel pipe, and a reinforcing arrangement comprising prestressed concrete type steel strand wound around the outside of the hollow tubular member.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation-in-part application, the contents of which are related to United States U.S. non-provisional patent application Ser. No. 11/483,076 filed on Jul. 7, 2006, which claims priority from non-provisional patent application having Ser. No. 10/410,486 filed on Apr. 3, 2003, now U.S. Pat. No. 7,084,766, which in turn claims priority to a provisional application having serial No. 60/371,063 filed on Apr. 8, 2002, the contents of which are incorporated herein by reference. FIELD OF THE INVENTION [0002] The invention relates to security tags in general, and in particular to a tag body containing at least one frangible vial containing a detrimental substance and an attaching means for use in electronic article surveillance (EAS) tags. BACKGROUND OF THE INVENTION: [0003] Various types of electronic article surveillance (EAS) systems are known having the common feature of employing a marker or tag which is affixed to an article to be protected against theft, such as merchandise in a store. When a legitimate purchase of the article is made, the marker can either be removed from the article, or converted from an activated state to a deactivated state. Such systems employ a detection arrangement, commonly placed at all exits of a store, and if an activated marker passes through the detection system, it is detected by the detection system and an alarm is triggered. In addition, other tags are known that utilize ink vials that break and release a permanent staining fluid onto the article if the tag is not removed by an authorized individual. [0004] For example, U.S. Pat. No. 5,426,419 to Nguyen et al., and assigned to Sensormatic Electronics Corporation, discloses an EAS tag having an arcuate channel that extends from an opening thereof to the actual attaching assembly and the detaching mechanism thereof. The channel increases the susceptibility of defeat of the attaching assembly because it guides an object that is inserted by an unauthorized individual directly to the attaching assembly and allows disengagement thereof. In addition, that the tag may be cut in half at the store such that the electronic components are left at the retail location and the unscrupulous individual absconds with the garment because the electronic detectors cannot detect the tag. In a safe environment away from the retail location and without any urgency, the unscrupulous individual is able to defeat the attaching pin. [0005] U.S. Pat. No. 6,373,390 to Hogan et al., assigned to the same assignee as the '419 patent, is an improvement patent issued in light of the shortcomings of the '419 patent. The '390 patent admits that the EAS tag of the '419 patent “can be defeated by insertion of a segment of relatively rigid metal bent in an arcuate manner to simulate the arcuate probe of the associated detacher device.” Furthermore, the '390 patent describes a fish tape which may be formed to resemble the requisite arcuate probe in order to defeat the EAS tag of the '419 patent, “the formed fish tape 50 is strong enough to hold its form when pushed into arcuate channel 7 until it can be manipulated into and against member 6, which then can be rotated to release tack assembly 4.” However, the improvement does not address the cutting of the tags by unscrupulous individuals to defeat detection of the electronic components. [0006] With respect to the '419 and '390 patent, many free standing arcuate probes have been either manufactured or misappropriated by unscrupulous individuals by dismantling the detacher components with which the probes are associated. The arcuate probe is inserted into the arcuate channel by hand and is led directly to the preventing mechanism. In the '390 device, the arcuate channel leads the manipulated arcuate probe to the opening or slot located in the arcuate channel, wherein the opening further aligns and guides the hand manipulated probe directly to the preventing mechanism or member. In addition, the force required to release the preventing mechanism of the '419 and '390 device is less than the force required to release the preventing mechanism of the instant invention. Accordingly, an unscrupulous individual may easily defeat the preventing mechanism of the '419 and '390 devices by manipulating an illicitly acquired freestanding arcuate probe. [0007] The '419 and '390 devices may be defeated by penetrating the bottom housing in proximal relation to the preventing mechanism and inserting a rigid and elongated element and forcing metal clip to rotate, whereby the preventing mechanism will release the pin. The instant device is more difficult to defeat in this manner because it will result in breakage of the ink vial to release the permanent staining substance onto the article. [0008] In addition, the preventing mechanism of the '419 and '390 patents is attached on only one end thereof, thus allowing movement out of the horizontal plane. Consequently, the vertical movement of the clamp increases the susceptibility of defeat of the attaching assembly because the jaws expand more easily because the angle of the clamp varies between the first end and second end as a result of the vertical movement of the non-secure end. The pull force to disengage a pin from the instant device and the '419 device was conducted by using an Imada product model DPS220R, obtainable from 450 Skikie Blvd. #503, N. Brook, Ill. 60062. [0009] The prior art does not address the need for an EAS tag that is difficult to defeat. In addition, the prior art fails to provide a clamp assembly that requires greater pull force to disengage a pin from the clamp assembly. In addition, the prior art fails to provide a tag that is more difficult to defeat even when an unscrupulous individual has illicitly acquired a freestanding arcuate probe. Further, the prior art fails to address the severance of the electronic component from the attaching component as a way to unscrupulously remove the article from the retail environment. Therefore, there remains a long standing and continuing need for an advance in the art of EAS tags that is more difficult to defeat, is simpler in both design and use, is more economical, efficient in its construction and use, and provides a more secure engagement of the article. SUMMARY OF THE INVENTION [0010] Accordingly, it is a general object of the present invention to overcome the disadvantages of the prior art. [0011] Therefore, it is a primary objective of the invention to provide an EAS tag that is more difficult to defeat. [0012] It is another objective of the invention to provide a cost-efficient EAS tag. [0013] It is another objective of the invention to provide an EAS tag that releases a detrimental substance if it is tampered with. [0014] It is yet another objective of the invention to provide an EAS tag that decreases the likelihood of defeat by an unscrupulous individual. [0015] It is a further objective of the invention to provide an EAS tag that is detachable when used with an authorized detaching unit. [0016] In keeping with the principles of the present invention, a unique EAS tag is disclosed wherein an ink vial is housed within the tag body to prevent cutting off of the electronic region of the tag body from the attachment region of the tag that attaches the tag to the object to be monitored. In addition, the ink vial deters unscrupulous individuals from tampering with tags that are capable of functioning with probes that disengage the attaching mechanisms. [0017] Such stated objects and advantages of the invention are only examples and should not be construed as limiting the present invention. These and other objects, features, aspects, and advantages of the invention herein will become more apparent from the following detailed description of the embodiments of the invention when taken in conjunction with the accompanying drawings and the claims that follow. BRIEF DESCRIPTION OF THE DRAWINGS [0018] It is to be understood that the drawings are to be used for the purposes of illustration only and not as a definition of the limits of the invention. In the drawings, wherein similar reference characters denote similar elements throughout the several views: [0019] FIG. 1 is a side elevational view of the tag of the instant invention in an assembled state. [0020] FIG. 2 is a side elevational view of the tag of the instant invention in an unassembled state. [0021] FIG. 3 is a perspective exploded view of the tag of the instant invention and the components thereof. [0022] FIG. 4 is a top plan view of the interior of second half of the instant tag with the tracks installed. [0023] FIG. 5 is a top plan view of the interior of second half of the instant tag with the tracks and the attaching member installed. [0024] FIG. 5A is an exploded view of an alternate preferred embodiment of the tag body incorporating the vial. [0025] FIG. 5B is an exploded view of another alternate preferred embodiment of the tag body incorporating the vial. [0026] FIG. 5C is an exploded view of another alternate preferred embodiment of the tag body incorporating the vial. [0027] FIG. 6 is a top plan view of the interior of first half of the instant tag illustrating an alternate preferred embodiment for accommodating an alternate resilient member. [0028] FIG. 7 is a top plan view of the interior of second half of the instant tag illustrating an alternate preferred embodiment for accommodating an alternate resilient member that attaches to first half illustrated in FIG. 6 . [0029] FIG. 8 is a top plan view of the interior of first half of the instant tag illustrating an alternate preferred embodiment for accommodating an alternate resilient member. [0030] FIG. 9 is a top plan view of the interior of second half of the instant tag with the attaching member installed illustrating an alternate preferred embodiment for accommodating an alternate resilient member that attaches to first half illustrated in FIG. 8 . [0031] FIG. 10 is a perspective view of the interior of first half of the instant invention. [0032] FIG. 11 is a perspective view of the interior of second half of the instant invention without the components therein. [0033] FIG. 11A is a perspective view of the interior of second half of the instant invention with the tracks and attaching member installed. [0034] FIG. 12 is a perspective view of a pin used with the instant invention. [0035] FIG. 12A is a frontal perspective view of the attaching member of the instant invention. [0036] FIG. 12B is a front elevational view of the attaching member of the instant invention. [0037] FIG. 12C is a side perspective view of the attaching member of the instant invention. [0038] FIG. 12D is a top perspective view of the first and second tracks used in the instant invention. [0039] FIG. 13 is a top plan view of the interior of the first half of an alternate preferred embodiment of the instant invention illustrating additional pillars and walls that may be placed within the tag to thwart an unauthorized probe insertion. [0040] FIG. 13A is a top plan view of the interior of the second half of an alternate preferred embodiment of the instant invention illustrating additional pillars and walls that may be placed within the tag to thwart an unauthorized probe insertion that attaches to first half illustrated in FIG. 13 . [0041] FIG. 14 is a top plan view of the interior of the first half of an alternate preferred embodiment of the instant invention illustrating additional pillars that may be placed within the tag to thwart an unauthorized probe insertion. [0042] FIG. 14A is a top plan view of the interior of the second half of an alternate preferred embodiment of the instant invention illustrating additional pillars that may be placed within the tag to thwart an unauthorized probe insertion and attaches to the first half illustrated in FIG. 14 . [0043] FIG. 15 is an electrical schematic diagram of the resonant tag circuit. [0044] FIG. 16 is a perspective view of the resonant tag circuit. [0045] FIG. 17 is a block diagram of an article surveillance system incorporating the resonant tag circuit. [0046] FIG. 18 is a cross-sectional view of a resonant tag system taken along line 18 - 18 of FIG. 16 . DETAILED DESCRIPTION OF THE INVENTION [0047] Referring now to FIGS. 1 and 2 , a tag 20 is illustrated having a first half 22 and a second half 24 . First and second halves 22 and 24 are preferably made of a hard or rigid material. A usable rigid or hard material might be a hard plastic such as, for purposes of illustration but not limitation, an injection molded ABS plastic. If a plastic material is used, the mating of a first side wall 26 to a second side wall 28 can accomplished via an ultrasonic weld or like joining mechanism. However, it is to be understood that other joining methods, such as adhesives, may also be used. When first half 22 and second half 24 are securely joined, first sidewall 26 and second sidewall 28 form a peripheral outer wall of tag 20 . Second half 24 has an apex region 25 that extends therefrom in an opposing direction to first half 22 . [0048] Now referring to FIGS. 3, 4 , 5 , 11 , and 11 A, an exploded perspective view, top plan view, and perspective views illustrate the interior of second half 24 . Second half 24 receives at least a first track 30 therein, and in a preferred embodiment it also receives a second track 32 . First track 30 is tightly received within at least a first slot 31 and second track 32 is received tightly within at least a second slot 33 , such that tracks 30 and 32 are maintained in substantially parallel relations. Tracks 30 and 32 are made of a hard material such as, but not limited to, metal, which enhances the durability and performance of the tag 20 . [0049] An attaching member 34 , as described in greater detail hereinafter, slideably rests on at least first track 30 , but in a preferred embodiment, rests on both first and second tracks 30 and 32 . Attaching member 34 has a resilient member 36 that normally maintains an opening 38 defined on said attaching member 34 in axial alignment with an aperture 40 defined on the inside of second half 24 and a hole 42 defined on the interior of first half 22 . In one preferred embodiment, attaching member 34 is made of spring sheet metal. Resilient member 36 may be a resilient lever arm 43 and in an alternate preferred embodiment, as illustrated in FIGS. 7 and 9 , at least one spring 44 may be substituted for the resilient lever arm 43 . Resilient member 36 is maintained in proximal relations to a barrier 45 , such that attaching member 34 is maintained in axial alignment described above. [0050] Now referring to FIGS. 6, 8 , and 10 , the interior of first half 22 is illustrated having a reinforcement means 46 defining opening 42 . Reinforcement means 46 extends inwardly but does not interfere with the sliding action of attaching member 34 on first and second tracks 30 and 32 . At least a first ridge 48 extends inwardly from the interior of first half 22 and is in proximal relation to first track 30 . In a preferred embodiment, a second ridge 50 also extends inwardly from the interior of first half 22 and is in proximal relation to second track 32 . Ridges 48 and 50 prevent upward movement of attaching member 34 , yet do not interfere with the sliding arrangement of attaching member 34 over first and second tracks 30 and 32 . Ridges 48 and 50 are in substantially parallel relations to one another. [0051] Now referring to FIG. 12 and FIGS. 11 and 11 A again in particular, in addition to the previous FIGS, a plurality of devices has been provided to prevent unauthorized manipulation and disengagement of attaching member 34 . When first half 22 and second half 24 are assembled, a shaft 52 , having a plurality of indentations 54 at predetermined intervals along the length thereof, is inserted through hole 42 and is received securely yet removably within opening 38 of attaching member 34 . Shaft 52 further extends into aperture 40 , which is defined by a tubular formation 41 extending inwardly from second half 24 . A top 55 is securely maintained at one end of shaft 52 , such that an opposing end of shaft 52 traverses an article to be monitored and is maintained within opening 38 of attaching member 34 and aperture 40 , whereby the article is securely bound between top 55 and outer surface of tag 20 . [0052] Now also referring to FIGS. 12A, 12B , and 12 C, attaching member 34 has a forward edge 75 and a distal rearward edge 77 . An attaching region 78 is defined proximal to the forward edge 75 and resilient member 36 is located proximal to rearward edge 77 . A first region 80 and a second region 82 are divided by attaching region 78 . A first lip 84 extends downwardly from first region 80 and a second lip 86 extends downwardly from second region 82 , such that first lip 84 and second lip 86 are in substantially parallel relations to one another, and each of the lips 84 and 86 are in substantially perpendicular relation to first and second regions 80 and 82 respectively. A first interior wall 88 and a second interior wall 90 are created by lips 84 and 86 respectively. First lip 84 and second lip 86 extend beyond rearward edge 77 and form a first outward curve 92 and a second outward curve 94 respectively, on a side of attaching member 34 proximal to resilient member 36 . Opening 38 of attaching member 34 is defined by a first jaw 96 and an opposing second jaw 98 . Jaws 96 and 98 extend downwardly from the plane of first and second regions 80 and 82 and are in proximal relations when they define opening 38 . However, jaws 96 and 98 are flexible such that they can move towards one another to decrease the size of opening 38 or they can move away from one another to increase the size of opening 38 . As a result, shaft 52 is maintained within opening 38 as defined by jaws 96 and 98 in a secure, yet removable, manner. [0053] Now also referring to FIG. 12D , first track 30 has a first top edge 100 and a first bottom edge 104 which are distal to one another and are interconnected by a first front edge 108 and an opposing first back edge 112 . Second track 30 has a second top edge 102 and a second bottom edge 106 which are distal to one another and are interconnected by a second front edge 110 and an opposing second back edge 114 . First back edge 112 and second back edge 114 are curved to accommodate the curved portion of second side wall 28 where apex 25 is created. First track 30 has a first outer surface 116 and a first inner surface 120 and second track 32 has a second outer surface 118 and a second inner surface 122 . [0054] In order to disengage shaft 52 from jaws 96 and 98 , enough force must be applied to forward edge 75 of attaching member 34 to overcome the force exerted by the resilient member 36 , and to move attaching member 34 towards rearward edge 75 . In addition, the force must be sufficient to overcome the frictional force created between first interior wall 88 and second outer surface 118 and the frictional force created between second interior wall 90 and first outer surface 116 . In order to do so, a probe 8 of a predetermined shape and length must be inserted through entrance 56 of tag 20 and extend to attaching member 34 to apply the sufficient necessary force to forward edge 75 to overcome the force exerted by the resilient member 36 and the frictional force described above to allow sufficient linear movement along first and second tracks 30 and 32 to disengage and remove shaft 52 from first and second jaws 96 and 98 . U.S. Pat. No. 4,738,258 is hereby incorporated by reference for teaching the probe 8 required and the necessary actuation thereof for insertion into entrance 56 . U.S. Pat. No. 4,738,258 can be modified into the disengagement apparatus illustrated in U.S. Pat. No. 5,426,419 and U.S. Pat. No. 5,535,606, the teachings of the detachers are also incorporated herein by reference. [0055] To determine the force required to disengage the shaft 52 from jaws 96 and 98 of attaching member 34 of the instant invention as compared to the tag of the '419 patent, the following experiment was conducted on ten tags 10 of the instant invention and ten tags produced in accordance with the specification of the '419 patent. A spring balance was hung on a wall, with its spring loading hook at the bottom. Two ends of a cotton sling were tied to form a loop. One end of the loop was secured on the hook of the balance whereas the other end was wound through the handle such that a downward pull force on the detacher (as illustrated in FIGS. 11 and 12 of the '419 patent) led to the squeezing of the detacher's trigger. Because the spring balance is in series with the sling, a measure of the triggering force to detach the tack shaft 52 could be measured. On average, approximately five pounds more force was required to detach the shaft 52 from the attaching member 34 of the instant invention than the tag of the '419 patent. [0056] In order to defeat the introduction of unauthorized probes into entrance 56 , several false paths and barriers are provided within tag 20 and the arcuate channel of the '419 patent and the '390 patent are completely eliminated. Because apex region 25 of tag 20 is constructed to be securely retained within a nesting or cradle area of a detacher, as taught by the '419 patent, tag 20 does not require any arcuate channels to lead the detaching probe 8 to the forward edge 75 of the attaching member 34 . The predetermined shape of the detaching probe 8 and the predetermined positioning of the attaching member 34 allow an authorized individual using an authorized detacher to disengage the shaft 52 from jaws 96 and 98 , thereby releasing the attached article. Dashed line 99 , of FIG. 5 , illustrates a proper path that may be taken by the detaching probe 8 . [0057] However, to defeat even the introduction of a probe that has been illicitly disassembled from an authorized detacher, a first partition 58 prevents entrance of the unauthorized probe if at an incorrect plane. A second partition 60 having a greater height than first partition 58 , also prevents the introduction of an unauthorized probe to attaching member 34 . A first pillar 62 and a second pillar 64 also prevent application of force to attaching member 34 by an unauthorized probe by deflecting the same. A third partition 66 , a fourth partition 68 , a fifth partition 70 , and sixth partition 72 are at different levels and define a plurality of cavities 74 therebetween. Cavities 74 extend within apex region 25 and are substantially perpendicular to the plane of attaching member 34 , such that an unauthorized probe inserted through apex region 25 will be retained within a single cavity 74 and will not be able to manipulate attaching member 34 laterally to disengage shaft 52 . [0058] Furthermore, if an unauthorized probe is being manipulated by hand, the probe will not be inserted at the correct plane to make proper contact with forward edge 75 of attaching member 34 to disengage the same. Instead, the unauthorized probe will go into the space defined between attaching member 34 and the different partitions 66 , 68 , 70 , and 72 . FIGS. 13 and 13 A teach an alternate preferred embodiment with different barriers to prevent access to the attaching member 34 of tag 20 . FIG. 14 and 14 A teach an alternate preferred embodiment with further different barrier arrangements to prevent access to the attaching member 34 of tag 20 . [0059] Referring now also to FIG. 15 , therein is illustrated a schematic diagram of a resonant tag circuit 124 . In a preferred embodiment, circuit 124 has at least an inductive element 126 and at least a capacitance element 128 connected in a series loop and forming an inductive capacitance (LC) resonant circuit 124 . The resonant tag circuit is employed in connection with electronic article security systems particularly electronic article security systems of the radio frequency or RF electromagnetic field type. Such electronic article security systems are well known in the art and a complete detailed description of the structure and operation of such electronic article security systems is consequently not necessary for an understanding of the present invention. [0060] However, as illustrated in FIG. 17 , such electronic article security systems employing resonant tag circuits include a transmitting means 130 for transmitting electromagnetic energy at or near the resonant frequency of the resonant tag into or through a surveillance zone 132 . A detecting means 134 monitors the surveillance zone 132 for the presence of a resonant tag within the surveillance zone 132 . Surveillance zone 132 is generally proximate to an entrance and/or exit of a facility such as, but not limited to, a retail store. The security system's function is to detect the presence within the surveillance zone 132 a monitored article having a resonant tag circuit 124 attached thereto in a secure fashion. [0061] In such a system, transmitting means 130 transmits pulses in the form of RF bursts at a frequency in the low radio-frequency range, such as 58 kHz in a preferred embodiment but may be adapted to be at any appropriate frequency as desired. The pulses (bursts) are emitted (transmitted) at a repetition rate of, for example 60 Hz AC cycle, with a pause between successive pulses. The detecting means 134 includes a receiver 136 which is synchronized (gated) with the transmitting means 130 so that it is activated only during the pauses between the pulses emitted by the transmitting means 130 . The receiver 136 expects to detect nothing in these pauses between the pulses. If an activated tag is present within the surveillance zone 132 , however, the resonator therein is excited by the transmitted pulses, and will be caused to oscillate at the transmitter frequency, i.e., at 58 kHz in the above example. The resonator emits a signal which rings at the resonator frequency, with an exponential decay time (“ring-down time”). The signal emitted by the activated tag, if it is present between transmitting means 130 and the receiver 136 , is detected by the receiver 136 in the pauses between the transmitted pulses and the receiver accordingly triggers an alarm 138 . Alarm 138 may be audible and/or visual or can be a silent alarm that is detected by any means known in the art. [0062] In a preferred embodiment, to minimize false alarms, the detecting means 134 usually must detect a signal in at least two, and preferably four, successive pauses; however, it is to be understood that the present invention can be adapted to function within one pause. Furthermore, in order to further minimize false alarms, such as due to signals produced by other RF sources, the receiver 136 employs two detection windows within each pause. The receiver 136 integrates any 58 kHz signal (in this example) which is present in each window, and compares the integration results of the respective signals integrated in the windows. Since the signal produced by the tag is a decaying signal, if the detected signal originates from a resonator in a tag it will exhibit decreasing amplitude (integration result) in the windows. By contrast, an RF signal from another RF source, which may coincidentally be at, or have harmonics at, the predetermined resonant frequency, would be expected to exhibit substantially the same amplitude (integration result) in each window. Therefore, alarm 138 is triggered only if the signal detected in both windows in a pause exhibits the aforementioned decreasing amplitude characteristic in each of a number of successive pauses. [0063] For this purpose, as noted above, the receiver electronics is synchronized by a synchronization circuit with the transmitter electronics. The receiver electronics is activated by the synchronization circuit to look for the presence of a signal at the predetermined resonant frequency in a first activation window of about 1.7 ms after the end of each transmitted pulse. For reliably distinguishing the signal (if it originated from the resonator) integrated within this first window from the signal integrated in the second window, a high signal amplitude is desirable in the first window. Subsequently, the receiver electronics is deactivated, and is then re-activated in a second detection window at approximately 6 ms after the original resonator excitation, in order to again look for and integrate a signal at the predetermined resonant frequency. If such a signal is integrated with approximately the same result as in the first detection window, the evaluation electronics assumes that the signal detected in the first window did not originate from a marker, but instead originated from noise or some other external RF source, and alarm 138 therefore is not triggered. [0064] Now also referring to FIGS. 16 and 18 , therein is illustrated a preferred embodiment of the resonant tag circuit 124 . Inductive element 126 is formed by a conducting member 140 that is made of any material that is capable of conducting electricity, and in a preferred embodiment is made of copper. Conducting member 140 is coiled around a first member 142 that is preferably constructed of a non-conductive material such as, but not limited to, plastic and rubber. First member 142 has a first wall 144 and a second wall 146 that are interconnected by a middle portion 148 . First wall 144 , second wall 146 , and middle portion 148 axially define a cavity 150 extending therethrough. [0065] Middle portion 148 is adapted to receive conducting member 140 thereon in a coiled fashion on an outer surface 152 thereof between first wall 144 and second wall 146 . Middle portion 148 has an inner surface 154 that defines cavity 150 . A magnetic member 156 is adapted to be received within cavity 150 and to be frictionally retained within inner surface 154 of middle portion 148 . Magnetic member 156 may be a ferromagnetic material or any other material having magnetic properties, and in a preferred embodiment, magnetic member 156 is made of amorphous metals. [0066] Capacitance element 128 is a parallel plate capacitor formed of conductive material on a first plate and a second plate (not shown) that are known in the art. Capacitance element 128 is adapted to be received on first member 142 , and in a preferred embodiment is received on first wall 144 thereof. First plate and second plate of capacitance element 128 are attached to opposing ends of conducting member 140 to form a series circuit. [0067] When resonant tag circuit 124 enters a surveillance zone 132 it is subjected to an electromagnetic field and magnetic member 156 is charged. As the electromagnetic field is removed, the stored magnetic energy stored in the magnetic member 156 is released and thus an ac current is generated within inductive element 126 and capacitance element 128 . When an ac voltage is applied to the resonant tag circuit 124 , the current depends on the frequency thereof. The resonant frequency of circuit 124 can be determined by the following equation: fo = 1 2 ⁢ π ⁢ LC [0068] Wherein f 0 is the resonant frequency of the circuit and L is the inductance and C is the capacitance. As can be ascertained from the equation, many possible combinations yield the desired resonant frequency, however, the L to C ratio is preferably kept high in order for the circuit to be selective and minimize undesirable resonances to disturbances close to the resonant frequency thus minimizing false alarms. In a preferred embodiment, optimal values were determined to be L=2.08 mH and C=3.6 nF thus yielding an L to C ratio of b 577 , 777 . 78 . [0069] It is to be understood that resonant tag circuit 124 is of sufficient size to be stored within casings used in article surveillance systems. Specifically, tag circuit 124 is of sufficient size to be received and enclosed within compartment 76 of tag 20 . Compartment 76 is defined by a peripheral wall 158 extending inwardly from second half 24 to enclose the resonant tag circuit 124 therein. A false path 160 is created between second side wall 28 and peripheral wall 158 . [0070] If an article having resonant tag circuit 124 attached thereto via tag 20 is moved into the surveillance zone 132 , the alarm 138 will be activated by circuit 124 to signify unauthorized removal of the article through a specified area. For purposes of illustration but not limitation, in a preferred embodiment, the length of circuit 124 is less than 2 cm and the radius thereof is less than 1 cm. However, it is to be understood that alternate sizes and shapes of circuit 124 will also function as taught and alternate electronic detection circuits as are known in the art may also be used. [0071] Now also referring to FIGS. 5, 5A , 5 B and 5 C, unscrupulous individuals have taken a garment protected by tag 20 into a dressing room of a retail location and used tools, such as hand held cutters, to sever the body of the tag 20 to remove and discard the resonant tag circuit 124 in the dressing room. The unscrupulous individuals are then able to abscond with the garment with the shaft 52 and attaching member 34 attached to the garment without setting off the electronic detection circuit. In the safety of their own home, the unscrupulous individual has the necessary time and larger equipment to manipulate the attaching member 34 to disengage the shaft 52 from the garment. [0072] At least one vial 170 is positioned within first half 22 and second half 24 such that it does not interfere with the movement of attaching member 34 . The vial 170 is known in the art and is preferably made of breakable glass which can be modified to break at a predetermined pressure application. Vial 170 contains a heavily staining and/or ill-smelling substance, preferably a liquid or gas under pressure, which is able to adhere durably to article to which tag 20 is attached, thereby rendering the article unusable. If an unauthorized person attempts to cut tag 20 or uses force to disengage the pin from the article being monitored, vial 170 will break causing said staining and/or ill-smelling substance to be expelled onto the article. To aid in the expulsion of the staining and/or ill-smelling substance, at least an orifice 172 is defined through first half 22 and second half 24 . [0073] To prevent unauthorized insertions of foreign objects through orifice 172 , vial 170 can be positioned within first half 22 and second half 24 to occlude orifice 172 . Vial 170 may be maintained in position by frictional engagement, adhesive, or resilient protrusions that extend inwardly from either first half 22 or second half 24 and firmly engage vial 170 therebetween. In one preferred embodiment, vial 170 is frictionally maintained within false path 160 between second side wall 28 and peripheral wall 158 . Vial 170 , however, may also be positioned in other desirable locations as illustrated in the figures to prevent the cutting of the body of tag 20 . Vial 170 is positioned to cover an area 173 between the resonant tag circuit 124 and the attaching member 134 . [0074] Now referring to FIG. 13 A , in order to increase the susceptibility of the vial 170 to breakage, a pressure point 174 extends inwardly from either first half 22 or second half 24 and engages a portion of vial 170 . Thereby, an application of force to the outside of tag 20 by unauthorized tools will force pressure point 174 toward vial 170 and cause breakage thereof and expulsion of the staining or ill-smelling fluid or substance. [0075] While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of one preferred embodiment thereof. Many other variations are possible without departing from the essential spirit of this invention. Accordingly, the scope of the invention should be determined not by the embodiment illustrated, but by the appended claims and their legal equivalents.

An electronic article surveillance (EAS) tag having an attaching member 34 located therein and adapted to securely and releasably receive a shaft of a pin therein, whereby a predetermined arcuate probe is inserted through an opening and applies a requisite force to the attaching member to release the shaft. At least one frangible vial containing a detrimental substance positioned within the tag body to deter unauthorized manipulation of the tag.

You are an expert at summarizing long articles. Proceed to summarize the following text: SUMMARY OF THE INVENTION Substantially all buildings are provided with spigots by which water pressure is available exteriorly of the building. The common means of providing a source of water pressure exterior of a building is by means of a sillcock which extends through the building wall, usually a foot or two above ground level. In many residences wherein a raised floor is employed, the sillcock extends through the wall to a crawl space below the floor. In other buildings wherein a basement or below ground floor is provided, the sillcock typically extends through the exterior wall with a piping connection within an interior portion of the wall. Sillcocks typically include a spigot having a handle and means for connecting a hose or other item to the spigot, such as for watering lawns or shrubbery, washing windows, washing cars, or so forth. Since sillcocks are so frequently employed, they are a conventional plumbing item and the typical sillcock, which is sometimes referred to as a "freeze proof" sillcock, is formed of a long tubular member having a spigot with a handle and a hose connection at the first end and having a threaded piping connection at the second end. A valve is provided within the long tubular member adjacent the second end with a rod extending through the spigot and connected to the handle. Water remaining in the sillcock after the valve is turned OFF is supposed to be drained through the spigot and out the hose connection. In this way, the sillcock is supposed to be freeze proof, and if properly operated, functions in a freeze-proof manner assuming that the interior of the building where the piping connection is made always remains above freezing temperature. In practical operation, however, sometimes events occur which cause the sillcock to freeze. This can occur if a hose or other apparatus is left attached to the spigot so that even if the spigot is closed the tubular portion of the sillcock does not drain. If this happens during subfreezing temperatures, the tubular portion of the sillcock can freeze and the expansion caused by the freezing within the tubular portion can cause it to split open. When this occurs, such damage is not visibly ascertainable since it occurs within the wall of the building. The user may be unaware of a leaking sillcock. When the user then turns ON a defective sillcock, water can leak from the damaged tubular portion into the wall of the building and can cause substantial damage before the defect has been detected. The present invention provides a means for preventing damage to the wall of a building in the event of the inadvertent leakage of a sillcock. The invention includes the use of a tubular member of an internal diameter greater than the external diameter of the sillcock tubular portion and greater in internal diameter than the threaded connection at the second end of the sillcock. The tubular member is slipped over the sillcock plumbing connection and over the tubular portion providing an annular area between the exterior of the sillcock tubular portion and the interior of the tubular member. A first washer of an elastomeric material is positioned over the sillcock tubular portion and adjacent the spigot end. The washer has an external diameter to engage the internal wall of the tubular member. In like manner, a second elastomeric washer is positioned over the sillcock plumbing connection and onto the tubular portion to engage the interior of the tubular member adjacent the second end. The washer thereby supports the tubular member concentrically about the sillcock tubular portion and provides an annular area which is sealed at both ends. A small diameter opening is formed in the tubular member adjacent the first end. A small diameter drain tube is positioned within the opening. The drain tube first end communicates with the annular area within the tubular member. The drain tube second end extends below the spigot and exterior of the building. Adhesive material is applied to retain the drain tube within the opening so that the first end remains within the annular area. If the sillcock tubular portion develops a leak such as a result of freezing, manufacturing defect or for other reasons, the water leaking from the sillcock enters the annular area within the tubular member. The water is trapped within the annular areas by the elastomeric seals at each end and is drained exterior of the building through the drain tube. This accomplishes two purposes. First, damage to the building wall is prevented. Second, the drainage provides an indication to the building owner that a damaged sillcock exists so that it can be replaced. A better understanding of the invention will be had to the following description and claims, taken in conjunction with the attached drawings. DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view of an apparatus for use with a frost-proof sillcock exemplifying a means of practicing the invention. FIG. 2 is an elevational cross-sectional view of a portion of a building wall having a frost-proof sillcock installed therein and employing the apparatus of this invention as shown in FIG. 1, but in reduced scale. FIG. 2 demonstrates the use of the apparatus in conjunction with the sillcock to reduce the possibility of damage to a building wall if a leak develops in the sillcock. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings and first to FIG. 2, a cross-sectional portion of the exterior wall of a building 10 is shown. The wall has an opening 12 therethrough. The wall has an exterior surface 14 which is exposed to ambient temperature and in many parts of the world is occasionally exposed to subfreezing temperatures. The wall interior 18 is in a heated area or in an area insulated from ambient temperature so as to typically remain at all times above freezing. Thus, plumbing retained interiorly of the inner wall 16 is typically not subject to freezing whereas plumbing exterior of the wall 16 is subject to freezing. In addition, when the ambient temperature exterior surface 14 is exposed to below freezing, such below freezing temperature will extend particularly towards the interior wall 16 within opening 12. To provide a source of water pressure exteriorly of the building having wall 10, a frequent expedient is the use of a freeze-proof sillcock as illustrated in FIG. 2. The sillcock includes an elongated tubular portion 18 having on the forward end thereof a spigot 20. On the rearward end of tubular portion 18 is a plumbing connection 22 exemplified by the externally threaded fitting illustrated, but which could also be an internally threaded fitting. The spigot 20 includes an integral hose connector portion 24 and a handle 26 by which the flow of water is turned ON and OFF. Adjacent the second end or plumbing connection 22 and interiorly of the tubular portion 18 is a valve which is not shown since such is a common expedient. The valve is controlled by rod 28 extending from handle 26. In the typical operation of the sillcock thus described, the sillcock being indicated generally by the numeral 30 and being made up of components 18-28, is retained within opening 12 and functions as a freeze-proof method of providing a source of water pressure at the building wall exterior surface 14. The sillcock is termed to be "freeze proof" since when it is closed, the interior of the tubular portion 18 is drained through the hose connection 24. Thus, even in freezing weather, if the sillcock is used to provide a source of water pressure at the hose connection portion 24, after the water pressure is turned OFF, the sillcock is self draining. This system works satisfactorily except that if for any reason the hose connection portion 24 is blocked, such as by a hose or other apparatus left attached which does not permit the tubular portion 18 to be fully drained, the occurrence of subfreezing temperatures can cause the tubular portion 28 to be subjected to freezing. When this occurs, the formation of ice within the tubular portion can rupture the tubular portion 18. Thereafter, when the sillcock 30 is utilized, water can leak out of the ruptured tubular portion 18 and penetrate wall 10. Such leakage may not be detected for a long period of time resulting in substantial building damage since the leakage may not occur in such a way that the water passes out the opening 12 to the wall exterior surface 14. In addition to being ruptured by freezing, the tubular portion 18 may develop a leak as a consequence of manufacturing defects, or twisting of the spigot 22 by vigorous closing of valve 26. If spigot 22 is struck by an object, such as a lawn mower or the like, the tubular portion 18 may be bent causing it to leak. In any event, if a leak occurs in the sillcock tubular portion 18 the consequences can be very damaging and may go on undetected for a substantial length of time. The present invention combats the consequences of leakage in the sillcock tubular portion 18. For this purpose, the apparatus of FIG. 1 is employed which includes a tubular member 32. Tubular member 32 is of a length substantially equal to the length of the sillcock tubular portion 18 and may be formed of plastic, fiber glass or metal. The tubular portion 32 has an internal wall 34 the diameter of which is greater than the exterior diameter of the sillcock tubular portion 18, and, in addition, is greater in diameter than the plumbing connection portion 22 so that the tubular member 32 may be telescopically positioned over the rearward end of sillcock 30. Also received on the sillcock tubular portion 18 is a first seal member 36 which is preferably formed of elastomeric material such as natural or synthetic rubber or pliable plastic. The seal member 36 has an interior opening 38 of a diameter to be slideably received upon the sillcock tubular portion 18 and has sufficient elasticity so that is can be stretched over the plumbing connection 22. In the installation of the device of this invention the first seal member 36 is first positioned on the sillcock portion 18 contiguous with the spigot 20 before the tubular member 32 is positioned onto the sillcock. The first seal member 34 has an exterior diameter 40 which snugly receives the tubular member interior wall 34. A second seal member 42 which is preferably identical to the first seal member 36 has an opening 44 slideably received upon the sillcock member 38, and like seal member 36 is expandable so as to be positionable over the plumbing connection 22. Further, the second seal member 42 has an external cylindrical surface 46 which snugly receives the interior wall 34 of tubular member 32. When the tubular member 32 is positioned on the sillcock 30 with the first and second seal members 36 and 42 in position as shown, a closed annular area 46 (See FIG. 2) is formed about the exterior of the sillcock tubular portion 18. The tubular member 32 has a small diameter opening 48 which receives a small diameter drain tube 50, preferably formed of flexible plastic. The first end 52 of drain tube 50 is received within the interior of tubular member 32 and within the annular space 46. The second end 54 of the drain tube 50 extends externally of tubular member 32 and below the spigot 20 and exteriorly of the building wall exterior surface 14. To retain the drain tube within opening 48 and prevent is inadvertent removable, adhesive 56 is applied to the drain tube within the interior of tubular member 32. The drain tube 50 is secured to the tubular member 32 before the tubular member is inserted onto sillcock 30. With the apparatus in place as illustrated in FIG. 2, any leakage of water from the sillcock tubular member 18 is captured within the annular space 46. This water drains through the drain tube 50 and is discharged exteriorly of the building. This accomplishes two purposes. First, it prevents damage to the building wall 10. Second, drainage of water from the drain tube 50 provides an indication to the building owner that the sillcock is leaking and requires replacement. The claims and the specification describe the invention presented and the terms that are employed in the claims draw their meaning from the use of such terms in the specification. The same terms employed in the prior art may be broader in meaning than specifically employed herein. Whenever there is a question between the broader definition of such terms used in the prior art and the more specific use of the terms herein, the more specific meaning is meant. While the invention has been described with a certain degree of particularity it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled.

An apparatus for providing a frostproof sillcock for a structured wall having a spigot at one end and a pipe connection at the other, including a tubular member slid over the sillcock providing an annular area between the exterior of the sillcock and the interior of the tubular member. Elastomeric gaskets seal both ends of the tubular member. A small diameter opening in the tubular member adjacent the spigot receives a short length of small diameter flexible tubing so that one end of the tubing communicates with the annular area and the other end extends below the spigot and exteriorly of the building wall. Any leakage of the sillcock is thereby drained away.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS This application is a United States National Phase application of International Application PCT/EP2007/009616 and claims the benefit of priority under 35 U.S.C. §119 of German Patent Application DE 20 2006 016 981.4 filed Nov. 7, 2006, the entire contents of which are incorporated herein by reference. FIELD OF THE INVENTION The present invention relates to a combination device for performing different tasks such as snow throwing, mowing, scarifying, soil breaking, sweeping or the like by means of interchanging the work implements such that each implement is adapted for each respective task, whereby a machine frame is intended for taking on the respective work implement and letting it be driven in rotation, and that the respectively installed work implement is enclosed by a partially open cylindrical housing the rotational axis of which lies in parallel to that of the work implement. BACKGROUND OF THE INVENTION Combination devices of such nature have been known in various guises in the past: DE 2 017 981 A discloses one such combination snow thrower consisting of a basic machine. On such machine, various work implements can be interchanged by pulling out the axle pin. Work implements in cylindrical form can be used for tasks like salt sprinkling, snow clearing, ice and earth breaking, as well as lawn mowing and sweeping. Such cylindrical work implements can be rotated about an axis horizontal and parallel to the ground by means of a motor on board the machine. In order to throw snow, a cylindrically shaped snow throwing drum with transverse shoveling paddles as described in DE 2 017 981 A is used. Ice breaking is another feature of the device which can be realized by replacing the snow throwing drum with a steel spiky one. For sweeping of powdery snow, garden debris or the like, a sweeping drum can be deployed with steel or plastic bristles. For soil breaking, a tilling drum is used, whereby it is combined with paddle wheels that are covered and together with which the dug up soil will be blown to the side. For lawn mowing, a cutting reel is used whereby the grass clippings are blown forward by the paddle wheels (fan) into a container. The cutting reel takes the form of two cutting knives with two sweeping brushes located at the back and which are intended for sweeping grass cuttings into the fan. Another feature of the device in DE 2 017 981 A has a spreader that can be additionally attached to it for the purpose of sprinkling salt as well as soil fertilizer. Such combination device is penalized by the fact that not all its functionalities can be optimally designed for all the work tasks. In particular, in the case of snow throwing, a discharge chute is not provided for displacing snow at a further distance away during or at the end of the snow cutting process. DE 31 00 904 C2 refers to another embodiment of a motorized walk-behind machine for snow clearing, sweeping or scarifying. This machine shows a basic housing into which various work implements, as described already in DE 2 017 981 A, can be accommodated. According to DE 31 00 904 C2, additional side wheels can be mounted onto the housing such that the machine can be used as a scarifier. The side wheels however have to be mounted separately. Another disadvantage lies in the drive axis which, depending on the functionality, is supported from one side only, thereby leading to instability. In order to utilize the device as a sweeping machine or a snow thrower, the fixed housing and machine together are rotated about the work implement axis, thereby being brought into two distinctly different inclinations relative to ground. Furthermore, the device may for example be hampered by its inability to allow for height adjustment or the separation between the work implement and ground. The device is generally penalized in terms of its handling. DE 38 12 105 C2 proposes a combination device for garden and roads. The embodiment includes a housing that is forwardly half open and which caters for different work implements. The work implements in turn are housed within their own casings both of which can be mounted and fixed onto the main device housing. Work implements for lawn mowing, scarifying, throwing snow, sweeping and blowing have also been mentioned. According to DE 38 12 105 C2 and the claims therein, the work implements with their respective housings can be shifted sideways and subsequently locked into position within the device housing. In operation, the axis of the work implement is mechanically coupled to the device's own actuator by means of a pinion. The device is extremely troublesome to set up and requires individual housing for each work implement to be attached onto the main device housing. The combination device as referred to in U.S. Pat. No. 4,064,679 A shows yet another embodiment that can be adapted for lawn mowing, snow throwing and lawn sweeping. Due to the inter-changeability of individual work implements, the device is also capable of multiple tasking. However, the changing of work implements is complicated by the housing, whose side wall has to be physically dismounted first, by undoing a number of bolts, before finally being able to change over the work implements. Additional housing covers or housing attachments are included for the different functionalities, which further complicate the tool setup not to mention the provision for additional storage of individual parts. SUMMARY OF THE INVENTION The deficiency just described is overcome in accordance with the present invention wherein the changing of different work implements is simplified and functionally optimized. The work task is fulfilled by a combination including inter-changeable work implements which adapt to the tasks in the respective operating configurations, a base frame onto which the respective work implements can be mounted and driven in rotation and whereby the individually built in work implement is partially enclosed by a housing that runs parallel to the rotation axis of the work implement. The housing is rotatable about an axis parallel to the drive axis of and can be locked into its respective position depending on the work task at hand. Tool changing is hence made much easier through the rotatable housing of the combination device. Furthermore, tool changing is facilitated by having the housing only partially enveloping the work implement thereby permitting the necessary access. On the other hand, the housing can be brought to different positions, such that individual work tasks are optimally performed within the necessary work implement enclosure. In the preferred embodiment, the housing encloses the work implement over a wrap angle such that the housing opens itself relatively forward and downward in the first operating position, mostly downward in the second operating position, and relatively backward and downward in the third operating position. Through such arrangement, snow throwing for example can be optimally performed when the housing is fixed with its opening facing the front and pointing downward. Lawn mowing for example can equally and optimally be performed by having the housing face downward and backward. According to other features, the housing is equipped with rollers, wheels or rolling cylinders along its front and back edges that run parallel to the axis of work implement's rotation in such a way that the housing is supported off the ground by its back set of rollers, wheels or rolling cylinder when in the first operating position, the housing is not supported by any rollers, wheels or rolling cylinder when in the second operating position, the housing is supported off the ground by its front set of rollers, wheels or rolling cylinder when in the third operating position. In the case of snow throwing, instead of rollers, wheels or rolling cylinder, the housing can also be supported by conventional skids which is height adjustable. The possibility for height adjustment also applies to the rollers, wheels or rolling cylinder. The housing may be fitted with a scraper bar along its back edge in order to take up snow while the device is being used as a snow blower, and that the housing exhibits an opening in its first operating position on top of which a discharge chute can be attached. Through this configuration, the housing is best optimized for snow throwing. Through the rollers, wheels or rolling cylinder, the height of the scraper bar can be adjusted relative to ground in such a way that the combination device can best adapt to the respective working conditions. The housing comprises two side walls that can be mounted in relative rotation to the two side plates of the basic frame, and that in the first side plate, provision is made for the transmission axle, and that in the second side plate, an axle journal is available, such that the inter-changeability and the rotation of different work implements and their adjustability can be catered for. Through this configuration, the work implements can be changed over easily and secured within a cost-effectively and simply designed housing. The transmission axle is belt driven and that the respective work implements are coupled in rotation to and detachable from the transmission axle. Such form of transmission is especially easy to maintain. The base frame may form an integral part of the basic machine, and the basic machine exhibits means of transport in the form of wheels, with which the basic machine together with the base frame and the respective work implement can be driven on the ground. The basic machine may have wheels which are height adjustable. The wheels can be free running such that the combination device can simply be pushed along by hand. To lighten the work load, the same wheels can be motorized and whose coupling can be switched on or off. A motor actuator may be provided to drive the work implements via a pulley belt or the like. This motor actuator can also be used for driving the wheels via a switchable gear set. The configuration of the different interchangeable work implements, especially in relation to snow throwing, mowing, scarifying, soil breaking or sweeping are also described. It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components as set forth. As far as a self-contained walk-behind combination device is concerned, the wheels can also be driven by the on board motor actuator, as in the examples of snow throwing or lawn mowing, and the actuator in turn can also be switched on or off at will. The combination device can also be so configured that it can be built onto a communal care vehicle, a tractor or the like in the form of an attachment. Here also, it can be seen that the rotatable housing will facilitate the changing over of work implements as well as its optimal operation. All the work implements have in common a cylindrical form and that their axis of rotation is relatively parallel to the ground being worked on and runs across the direction of machine travel. The invention in its preferred embodiment will now be described and become more readily apparent on examination of the following description, including the appended drawings. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: FIG. 1 is a perspective view of the invention, namely the combination device with a rotatable housing excluding the work implement; FIG. 2 is a front view II of the combination device housing as referred to in FIG. 1 ; FIG. 3 is a cross-sectional view through the bearing fixture of the drive axis within the housing as referred to in FIG. 2 ; FIG. 4 is a perspective view of the combination device as referred to in FIG. 1 ; FIG. 5 is a perspective view of one work implement in the form of an augur for use with the combination device as a snow thrower; FIG. 6 a perspective view of the combination device as referred to in FIG. 1 with the augur as referred to in FIG. 5 as well as a discharge chute as mounted onto the housing; FIG. 7 a partial view VII of the snow thrower as implemented from the combination device in FIG. 6 ; FIG. 8 is a perspective view of one work implement in the form of a mowing reel with the so called upper blades equally spaced along its circumference; FIG. 9 is a perspective view of a so-called bed-knife which can be combined with the mowing reel in FIG. 8 of the combination device to become a lawn mower; FIG. 10 is a perspective view of the combination device showing the housing with the attached mowing reel as well as the bed-knife; FIG. 11 a partial side view XI of the combination device as referred to in FIG. 10 ; FIG. 12 is a perspective view of a work implement in the form of a scarifying cylinder with spring tines radiating substantially outwards; FIG. 13 a partial side view of the combination device with the attachment of the scarifying cylinder as referred to in FIG. 12 ; FIG. 14 is a perspective view of a work implement in the form of a tilling cylinder in perspective view; and FIG. 15 is a partial side view of the combination device with the attachment of the tilling cylinder as referred to in FIG. 14 . DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings in particular, FIG. 1 shows the principal configuration of a combination device 1 in its perspective view. To the rear of the combination device 1 , a wheel frame 2 is shown and which comprises two bent guide rods 3 and 4 , whose upper ends transform into the respective hand grips 5 and 6 . At the lower end of the guide rods 3 and 4 , two wheels 7 and 8 are mounted by means of fixture 9 which enables height adjustment along the guide rods 3 and 4 . Furthermore, the combination device exhibits a base frame 10 , whose front end is mounted with two vertical side plates 11 and 12 . The side plates 11 and 12 are fixed onto but detachable from the base frame 10 . The base frame 10 is bolted together with the lower parts of the guide rods 3 and 4 by means of the palm grip 13 . In order to support and strengthen the combination device 1 , a stiffening bracket 14 is seen in the present embodiment with one end being attached to the guide rods 3 and 4 by means of the palm grip 15 , while the other end being attached onto the base frame 10 by means of fixtures 16 . Furthermore, a motor engine 17 can be seen in the present embodiment mounted onto the base frame 10 , and whose very outer end is mounted with a belt pulley 18 . The belt pulley 18 is connected to another belt pulley 19 via a pulley belt 20 . This pulley 19 serves the purpose of driving the transmission axle 21 , the detailed function of which will be described later. Lying coaxially to the transmission axle 21 , a gudgeoning pin 22 is seen to the right side of the “rear” side plate 12 , and which forms a straight line with the transmission axle 21 . This gudgeoning pin 22 as well as the transmission axle 21 can be axially and outwardly retracted in order to allow for the easy changing over of work implements. It is worth noting here that the basic design of the combination device 1 is capable of other embodiments. Important being the two side plates 11 and 12 with a housing 23 sitting in between. The housing 23 can be swung or pivoted about the transmission axle 21 as well as the journal 22 on both side plates 11 and 12 , which is shown in the first operating position in FIG. 1 . In the same operating position, it can be seen that the housing 23 is bolted down by means of two security bolts 24 one of which can be seen in FIG. 1 . It can also be seen in FIG. 1 that the housing 23 is shown with two side walls 25 and 26 that enable the housing to be mounted about a rotational axis parallel to the transmission axle 21 and to the gudgeoning pin 22 . Further details on the housing 23 will be explained later with reference to FIG. 4 . FIG. 2 shows the front view II, in particular, that of the housing 23 as in FIG. 1 . It is noticeable that the housing 23 with its side walls 25 and 26 is fitted in between the two side plates 11 and 12 . These assembly side plates 11 and 12 have on their inner sides clamp rings 27 and 28 that couple the housing 23 with its side walls 25 and 26 and enable them to rotate. The second security bolt 24 can also be seen in FIG. 2 . It can be further seen that the gudgeoning pin 22 projects into the housing 23 . The transmission axle 21 also displays a drive element 29 that partially projects into the housing 23 . The drive element 29 shows two diametrically opposite and radial projecting drive keys 30 and 31 , via which the transmission axle 21 can be rotationally coupled onto the respective work implement within the housing 23 . FIG. 3 shows an enlarged view of the transmission axle 21 in the area of the assembly side plate 11 . It can be seen that the drive pulley 19 is rotationally mounted with bearings 32 and 33 along the axle on either of its extreme end. The bearing 33 is seated respectively on the assembly side plate 11 . A support plate 34 outside at a distance away from and fixed onto the assembly plate 11 is as shown in FIG. 1 . The drive pulley 19 is drilled with a hole 35 in the center the inner side of which is cut with two diametrically opposite key slots 36 and 37 . In this key slot, the two drive keys 30 and 31 of the transmission axle 21 can be form fittingly taken up and remain axially adjustable. From the engaging position as shown in FIG. 3 , the transmission axle can be seen axially adjustable in the direction as indicated by the arrow 39 by means such as spring actuation (not shown here) and alike, to such extent that a work implement can be inserted in between the side walls 25 and 26 of the housing 23 . The fixation for the gudgeoning pin 22 is also designed in a similar fashion. In FIG. 3 , the tooth belt 20 can also be seen. As already mentioned previously, FIG. 4 shows the housing 23 in perspective view. This view of the housing 23 is already presented as the first operating configuration in FIG. 1 . The housing 23 comprises a partially open cylindrical outer wall 40 , which is fitted or for example welded with the side walls 25 and 26 . To the front of the outer wall 40 , there is a reinforcement fixture 41 formed on top and the front end within which is seen with a bearing shaft 42 . The bearing shaft projects out of the two side walls 25 and 26 such that on either side the wheels 43 and 44 are supported accordingly. To the back and at the bottom of the outer wall 26 , a lug plate 45 / 1 is shown here together with a second lug plate not displayed in the drawing, the purpose of which is to provide support for the back wheels 45 . Furthermore, it can be seen in FIG. 4 that in the rear edge 46 / 1 location of the housing 23 , a scraper 46 is provided whose function corresponds to that of a snow thrower. On the top of the outer wall 40 , an opening 47 can be further seen in the vicinity of which a chute adapter 48 is fitted. The chute adapter 48 serves as a removable mounting platform for the blowing chute 49 , as shown in FIG. 6 that can be typically found in the state-of-the-art snow thrower. On both the side walls 25 and 26 , locking fixtures 50 and 51 can be seen projecting radially with the purpose of fixing the housing 23 in between the assembly side plates 11 and 12 in the respective operating configuration. In the corresponding configuration, fixation holes 52 can also be seen on the assembly side plate 11 and 12 , as shown in FIG. 6 . The second fixation hole in the lower region of the side wall 11 is seen here hidden by the security bolt 24 , which projects and typically locks through the lower fixture hole 50 on the side wall 25 of the housing 23 . The fixing of the security bolts 24 can be realized by means of bolt nuts 53 and 54 welded onto the locking holes 50 and 51 . It can be seen further in FIG. 4 that both side walls 25 and 26 have round apertures 55 and 56 , upon which the respective assembly side plates 11 and 12 can be rotationally located, as shown in FIG. 2 . For the combination device 1 to perform as a snow thrower, as shown in FIGS. 1 and 6 , a snow augur 60 is shown in FIG. 5 , the front portion of which a coupling element 61 can be seen via which the transmission axle 21 with its key elements 30 and 31 can be coupled in firm rotation. On the other end of the rotational axle 62 , opposite to the coupling element 61 , an insertion hole can be found but which is not shown here in FIG. 5 . Further description on the snow augur 60 is deemed unnecessary as it conforms to the state-of-the-art. FIG. 6 shows the combination device 1 in its snow throwing configuration. It can be recognized that the housing 23 circumscribes the snow augur 60 partially, hence exposing the housing 23 forward in the travelling direction as indicated by the arrow 63 as well as backwards. The wheels 43 and 44 as described in FIG. 4 are functionally redundant in this operating state of the housing 23 . On the contrary, the wheels 45 , the configuration of which corresponds to those of the wheels 43 and 44 , are mounted onto the housing 23 in order to support the combination device 1 on its front end. This can be seen in particular from the side view as shown in FIG. 7 . It is noticeable that the wheels 45 are being supported by the ground 64 , hence defining through the same wheels 45 the vertical separation between the scraper 46 and the ground. By adjusting the height via the wheels 7 and 8 as shown in FIG. 6 , a pivotal movement will be resulted in the direction as shown by the double arrow 65 ( FIG. 7 ) with the whole combination device 1 pivoting about the rotating axis of wheels 45 , thereby enabling the vertical separation between the scraper 46 and the ground 64 to become adjustable. In this respect, the snow throwing function can be optimally adapted by means of special features such as those located on the housing 23 together with the wheels 45 . It can be seen further in FIG. 7 that the first operating configuration is fixed by means of the security bolt 24 . Apart from height adjustment via the wheels 7 and 8 , other means of setting the separation between the scraper 46 and the ground 64 is also possible and easily achievable within certain limitation. FIG. 8 shows a mowing reel 70 , as is generally regarded as state-of-the-art. The mowing reel 70 , as shown in FIG. 8 , comprises a multiple of so-called upper blades 71 which act together with the so-called lower blade 72 , as shown in FIG. 9 , to perform the grass cutting function. It can also be seen in FIG. 8 at the right hand side of the reel cylinder that the coupling journal 73 is equipped with two radially projecting take up slots 74 and 75 . With the slots 74 and 75 , the mowing reel 70 can be attached to the transmission axle 21 in firm rotation via the drive element 29 as well as the two radially projecting key elements 30 and 31 ( FIG. 2 ). On the opposite end of the mowing reel spindle 70 , a fixation hole 76 is located, into which the gudgeoning pin 22 of the assembly side plate 12 in FIG. 2 can be inserted. The lower blade 72 has two side mounted bolts 77 and 78 , with which the lower blade 72 can be mounted to the assembly side plates 11 and 12 , as shown in FIG. 10 out of the bottom view of the combination device 1 . The lower blade 72 can be adjusted in relation to the upper blades by means of two side adjustment screws 79 and 80 , such that mowing can be adapted to various cut quality. It is also possible to have the mowing spindle 70 together with the lower blade combined into one module which can then be inserted into the housing 23 of the combination device 1 . Referring to FIG. 10 and FIG. 11 , the housing 23 is now set in its third operating configuration as that of a lawn mower. In this third configuration, both wheels 45 as shown in FIG. 10 are rendered functionally redundant. On the other hand, both the other wheels 43 and 44 are now in contact with the ground 64 , such that the “frontal piece” of the whole combination device 1 is supported by the wheels 43 and 44 . This results in a vertical separation as can be seen in FIG. 11 , between the group of blades, comprising the upper blades 71 and the lower blade 72 , and the ground 64 . In the third operating configuration, the housing 23 is firmly bolted down by means of the security bolts 24 . The height adjustment is also made possible here via the wheels 7 and 8 that are attached onto the frame pillars 3 and 4 , thereby producing a pivotal effect on the combination device 1 about the rotation axis of the wheels 43 and 44 , the direction of which is as indicated by the double arrow 65 . In this way, a height adjustment is also catered for in the mowing function by setting the distance between the blades, both upper blades 71 and lower blade 72 , and the ground 64 , so as to achieve the required cutting height. In this configuration of the combination device 1 , the snow throwing chute 49 in FIG. 6 is without saying no longer needed and will be dismantled accordingly. The opening 47 as shown in FIG. 10 which functions as the snow throwing chute adapter 48 as shown in FIG. 11 is preferably to be covered up by means of say a protection cover which is not shown here in the drawing. Referring to FIG. 10 , a basket for grass collection, which is not shown here, can be placed behind the housing 23 . The basket can also serve as a protection device for the user who drives behind the combination device 1 . Such a basket can also be adapted for the scarifying, tilling or sweeping functions. FIGS. 12 and 13 show another function of the combination device 1 , whereby FIG. 12 shows the work implement in the form of a scarifying cylinder 85 . This scarifying cylinder 85 comprises a multitude of spring tines 86 that radiate out of the rotational axis and serve as means of aerating the soil in the lawn. The scarifying cylinder 85 in the presented form or in form equipped with radial airing blades is state-of-the-art and whose examples are plentiful. In FIG. 12 , the scarifying tool 85 is shown with an adapter at its end and two radial slots 88 and 89 , with which the scarifying tool 85 can be coupled in firm rotation to the drive element 29 of the transmission axle 21 via the two drive keys 30 and 31 (see FIG. 2 ). FIG. 13 shows the configuration of the combination device 1 as scarifier. It can be noticed that the housing 23 is set up in the same third operating configuration as when the combination device 1 is used as mower, as shown particularly in FIG. 11 . Accordingly the operating configuration is fixed in position by means of the security bolts 24 , whereby the wheels 45 are also made redundant here. The housing 23 is supported off the ground 64 by the wheels 43 and 44 in such a way that the penetrating depth of the spring tines 86 can be adjustably defined. Through the height adjustment of wheels 7 and 8 at both the frame pillars 3 and 4 ( FIG. 1 ), the whole combination device 1 can thus be seen pivoting about the bearing axis of the wheels 43 and 44 in direction as indicated by the double arrow 65 such that the penetrating depth of the spring tines 86 can also be adjusted. The combination device can be easily set up to function as scarifier. The housing 23 is there, as can clearly be recognized in FIG. 13 , opening itself up from beneath and towards the rear against the direction of travel as indicated by the arrow 23 . In yet another implement, the combination device 1 can be used as a tiller. To this, a work implement typically in the form of a tilling cylinder 95 can be seen in FIG. 14 . The tilling cylinder 95 , as is general known as the state-of-the-art, comprises the so-called cleavers which are used for ground breaking and soil loosening. FIG. 15 shows part of the side view of the combination device 1 , onto which the tilling cylinder 95 with its cleavers 96 is mounted. It can be seen that under this condition, the runners 45 as well as the runners 43 are made functionally redundant. This means that the housing 23 is fixed in its second operating configuration, and in this case bolted down to the assembly side plates 11 and 12 by the security bolts 24 . On account of this arrangement, the cleavers 96 project well beneath the housing 23 such that a reasonable soil depth penetration can be achieved here. By controlling the handgrips 5 and 6 of the combination device 1 , an optimal soil loosening is made possible. Instead of the exemplary work implements presented here so far, other cylindrical work implements such as a sweep roller can also be deployed. Through the respective turning of the housing 23 , such a sweep roller in the desired form can be hidden either towards the rear or partially towards the front, so that the combination device 1 can easily be converted into a sweeping machine. If the sweep roller is hidden by the housing 23 towards the front, then a sweep collector can be placed towards the rear for catching all the swept material. In this embodiment, the reversal of the direction of rotation will not be necessary as far as the sweeping function of the combination device 1 is concerned. In particular, with regards to the height adjustment for the respective work implements or their distance of separation relative to ground, the first and second configurations provide simple means of adjustment, such that the sweeping function and its effectiveness can also be height adapted by means of adjusting the wheels 7 and 8 . Also in this configuration, provision for a sweep collector is possible such that the direction of rotation will not need to be reversed and that extra protection to the user being hit by the swept material can also be provided. It is also possible to have a sweeper rolling against the direction of travel such that the ground material is always swept to the front. In this case, a sweep collector will not be necessary. In the case of such reverse transmission, the housing 23 is best recommended to adopt the snow throwing configuration i.e. facing front and open at the bottom as in the first operating configuration. It can also be noticed that in particular through the turning of the housing 23 , every function of the combination device 1 can be optimally adapted to the corresponding task in question. The changing of work implements is enormously simplified through the special design of the transmission axle 21 on the one hand, and the gudgeoning pin 22 on the other, such that by their being pulled out, the tool implements can be inserted into the combination device 1 or the housing 23 . Tool changing takes place when the housing 23 is in its first operating configuration, as shown typically in FIG. 1 . Also it can be imagined that the front part of the combination device 1 with its assembly side plates 11 and 12 as well as the housing 23 can be used as a tool attachment for say a communal service vehicle. The simple retooling and the optimal setting up through the rotatable housing can also be advantageous. While specific embodiments of the invention have been described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

A combination device ( 1 ) is provided for carrying out various work tasks, such as cutting snow, mowing, scarifying, soil breaking or the like. The device includes a plurality of interchangeable work implements ( 60 ) tailored to the respective work task. A basic frame is provided in which the respective work implement ( 60 ) is accommodated and can be driven to rotate, and wherein the respectively installed work implement ( 60 ) is partially enclosed by a housing ( 23 ) extending parallel to the axis of rotation of the work implement. In order to tailor the combination device optimally to the respective work task, provision is made for the housing ( 23 ) to be able to rotate about an axis parallel to the axis of rotation of the respective work implement ( 60 ) and to be fastened in various operating positions corresponding to the respective work task.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION [0001] The present invention relates generally to systems for injecting substances into underground formations, and in particular relates to novel systems and methods of combining fluids and proppant under high-pressure, and for injection of the resultant fluid stream into formations such as coal beds. BACKGROUND OF THE INVENTION [0002] The Horseshoe canyon coal formations in Alberta have been difficult to stimulate for coal bed methane production. These formations have been through a plethora of conventional stimulation treatments, ranging from foams to crosslink polymers. Due to the nature of the low reservoir pressures of these coal formations, or seams, and their sensitivity to damage by conventional stimulation fluids (defined herein as a liquid and/or gas), stimulation fluid recovery becomes almost impossible. The only other economically viable choices appear to be straight CO 2 or N 2 gas injection. High rate N 2 gas injection technique is a common practice in North American coal bed methane exploited plays, and CO 2 is used as a flood medium. [0003] Although using CO 2 gas to stimulate a formation works fine, it has certain drawbacks, including: 1. Costly treatments; and, 2. CO 2 does not clean up quickly, and since water is commonly produced during stimulation, it will turn into carbonic acid which is extremely hard on surface production manifolding. [0006] Using N 2 gas works the same way all fluids do to stimulate a formation, although extremely high rates are required to create enough stress to overcome the natural formation mechanics and actually fracture, or “frac”, the formation. Enhanced conductivity of a formation relies on the effect of hysteresis, namely when the frac faces come back together under stress, that these faces will not heal back to their original orientation. It would be desirable to use proppant (e.g. a sand or other suitable materials) to hold the fractured, or “fraced”, faces apart as used in conventional frac theory. However, the problem with this is that N 2 is pumped as a gas and will not suspend or carry proppant as do conventional fracturing fluid systems. [0007] What is desired therefore is a novel method of fracturing, or “fracing”, a target formation (such as a coal or shale formation) using gases and proppants, and a novel system for mixing such gasses and proppants in a manner that would result in an “impregnated” fluid stream suitable for such fracing. Preferably, the method and system should be capable of combining N 2 gas and a proppant material, such as sand, to produce a suitable fluid stream for fracing a coal formation. The method and system should further provide for introduction of surfactants to the fluid stream to further enhance the performance of the proppant in the target formation. SUMMARY OF THE PRESENT INVENTION [0008] According to the present invention, there is provided in one aspect a high-pressure injection proppant system (also referred to as “HIPS”) in which proppant, such as sand, is preloaded into one or more high-pressure cylindrical or spherical vessels, and such proppant is delivered into a fluid stream, such a N 2 gas stream, via an arrangement, such as a screw auger, which meters the proppant volumes and rates into the fluid stream. [0009] In another aspect the invention provides two vessels operationally mounted in parallel which can function separately or concurrently depending on the demand for proppant in a particular formation. When operated seperately, one vessel can be in use for fracing a formation while the other vessel is isolated, de-pressurized and reloaded with proppant via a pneumatic bulk proppant system. The other vessel is then ready for operation when the first vessel is depleted of proppant. [0010] In yet another aspect the invention provides for the injection of surfactants (i.e. chemicals or like substances) into the fluid stream to enhance the performance of the proppant, to aid in the placement of the proppant into the fracture network, and to demote proppant flowback during production and embedment. [0011] In another aspect the invention provides a high-pressure injection proppant apparatus comprising: [0012] at least one pressure vessel; [0013] means for filling the vessel with proppant; [0014] means for delivering a fluid containing nitrogen gas to the vessel and pressuzing the vessel therewith; and, [0015] a metering arrangement operatively coupled to the vessel and in fluid communication therewith for metering the proppant from the pressurized vessel into a fluid stream containing nitrogen gas for delivery to a target formation. [0016] In yet another aspect the invention provides a method of injecting proppant into a target formation comprising: [0017] providing at least one pressure vessel and a metering arrangement operatively coupled to the vessel and in fluid communication therewith; [0018] charging the vessel with proppant; [0019] pressurizing the vessel with a fluid containing nitrogen gas; and, [0020] operating the metering arrangement to meter the proppant from the pressurized vessel into a fluid stream containing nitrogen for delivery to the target formation. [0021] Further, the system of the present invention can be operated manually or by computer automation to aid in the accuracy of mixing of the components of the fluid stream. BRIEF DESCRIPTION OF THE DRAWING FIGURES [0022] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: [0023] FIG. 1 is an elevational side view of a mobile carrier carrying a high-pressure injection proppant system (“HIPS”) according to a first embodiment of the present invention, showing the cylindrical pressure vessels of the system in a reclined transportation mode; [0024] FIG. 2 is a view of the system of FIG. 1 with the pressure vessels in an elevated operating mode; [0025] FIG. 3 is a plan view of the rig and system of FIG. 2 ; [0026] FIG. 4 is an elevational end view of the rig and system of FIG. 2 ; [0027] FIG. 5 shows the system of FIG. 4 in isolation, with the rig omitted; [0028] FIG. 6 is a view similar to FIG. 4 , but shows a second embodiment of the system of the present invention, in operating mode; [0029] FIG. 7 is an elevational side view of the system of FIG. 6 ; [0030] FIG. 8 is a plan view of FIG. 6 with the front portion of the rig omitted; [0031] FIG. 9 is a perspective view, from the rear, of a third preferred embodiment of the system of the present invention showing a pair of spherical pressure vessels mounted on a mobile trailer; [0032] FIG. 10 is an elevational side view of the system of FIG. 9 ; [0033] FIG. 11 is a perspective view, from the front, of a fourth embodiment similar to the third embodiment, but having a single spherical pressure vessel; [0034] FIG. 12 is an elevational side view showing the vessel and piping of FIG. 11 in isolation; [0035] FIG. 13 is an elevational side view from the right side of FIG. 12 ; [0036] FIG. 14 is an elevational side view from the opposed back side of FIG. 12 ; [0037] FIG. 15 is an elevational side view from the left side of FIG. 12 ; and, FIG. 16 is a plan view from the top of FIG. 12 . LIST OF REFERENCE NUMBERS IN DRAWINGS [0000] 10 high-pressure injection proppant system 12 trailer 14 truck 15 hydraulic wet kit 16 axles of 12 18 wheels on 12 20 proppant bulk storage tank 22 low-pressure blower pump 24 first low-pressure air line 26 second low-pressure bulk load line 28 surfactant storage and pumping assembly 30 delivery tubing for 28 32 hydraulic lift cylinders 34 pivots 36 , 36 a , 36 b pressure gauges 38 densometer 40 pressure vessel(s) 42 outer wall of 40 43 reinforced portion of 42 44 inner chamber of 40 46 first vessel inlet for proppant 48 first/top end of 40 50 second vessel inlet/outlet 52 first vessel outlet 53 flange of 52 54 screw(s) 56 radial inlet of 54 57 radial outlet of 54 58 motor of 54 60 piping arrangement 61 high-pressure fluid stream 62 first inlet of 60 64 first (Y) diverter 66 first fluid stream 68 second fluid stream 70 venturi-type orifice 72 first outlet of 60 74 second (four way) diverter 76 first fluid sub-streams 78 second fluid sub-stream 80 piping 82 first valves of 60 84 third (T-shaped) diverter 86 third fluid sub-streams 87 fourth fluid sub-streams 88 second valves 90 third valves 92 piping 94 Y-joint 96 pressure vessel isolation valve 98 upstream injection port 99 downstream injection port 130 delivery line of second embodiment 140 pressure vessel(s) of second embodiment 142 outerwall of 140 144 a first inner chamber of 140 144 b second inner chamber of 140 144 c third inner chamber of 140 145 first bottomopening of 144 a 146 first vessel inlet 147 second top opening of 144 a 150 second vessel inlet 152 bottom vessel outlet of 144 c 154 screw(s) of second embodiment 158 motor of 154 160 piping arrangement of second embodiment 162 inlet 166 first fluid stream 167 Y-shaped diveter 168 second fluid stream 170 orifice 183 first valves 190 pressure relief valve 192 piping 196 isolation valve(s) 220 proppant storage tank 228 storage and pumping assembly 231 lower legs 240 spherical pressure vessel(s) 254 sand screw 280 valves 311 retractable arms 326 proppant supply line 327 proppant supply valve 340 pressure vessel 341 cap 346 proppant supply valve 350 top fluid inlet port 354 screw/auger 357 auger outlet 358 drive motor and seal assembly 360 piping arrangement 361 high pressure fluid stream/line 364 first fluid diverter 372 outlet 374 second fluid diverter 376 fluid auger by-pass line 380 piping for fluid by-pass 382 fluid by-pass line valve 388 top fluid supply valve 390 vent valve 391 cap for vent line 393 purge valve 394 y-joint (auger outlet by-pass) 395 choke 396 auger outlet valve 399 surfactant inlet DESCRIPTION OF EMBODIMENTS [0145] Reference is first made to FIGS. 1 to 3 which show a high-pressure injection proppant system, or “HIPS”, (generally designated by reference numeral 10 ) according to a first embodiment of the present invention. The system is mounted on a carrier, which is preferably a wheeled trailer 12 adapted to be pulled by a motorized vehicle, or truck 14 . It will be understood that the carrier may take various alternate forms, namely the trailer may itself be self-propelled, the truck and trailer may form one non-detachable unit, the system may be mounted on a skid for transport between sites, or the like. However, since the system is extremely heavy, not all carriers will be suitable for road transport as prescribed load limits for roads may be exceeded. Hence, in the present embodiment, the 24 wheeled trailer 12 is specifically designed to remain within such load limits (i.e. is “road legal”) by having three axles 16 with eight tires 18 per axle. Different axle and wheel combinations and quantities may be equally suitable, depending on the load to be transported. Likewise, the truck is suitably designed to haul the trailer 12 , and should include a hydraulic “wet kit” 15 to power the system 10 on the trailer. [0146] The preferred system 10 includes a proppant storage means in the form of a cone-shaped tank 20 located on the trailer 12 . A relatively low-pressure blower pump 22 , conveniently mounted on the truck 14 close to a power source (i.e. the hydraulic wet kit 15 ), communicates with the tank 20 via a first low-pressure line 24 . The pump 22 permits the bulk transfer of proppant from the tank 20 at the front of the trailer to the two high-pressure vessels 40 at the back of the trailer via at least one second loading line 26 ( FIG. 2 ). Although one line 26 may be configured for suitable delivery of proppant, each vessel has a designated line 26 in the present embodiment. [0147] The system further includes a surfactant storage and high pressure pumping assembly 28 located on the trailer. This assembly stores one or more surfactants for injection or “misting” (via a delivery tubing generally indicated by 30 ) into the high-pressure fluid stream associated with the pressure vessels 40 , as will be discussed later. The pumping assembly may employ as many high-pressure surfactant pumps as required. It is noted that in alternate embodiments, the assembly may be located elsewhere than on the trailer 12 , such as on another trailer, but must be capable of communicating with the fluid stream during operation for the desired misting. Likewise, the proppant storage tank 20 may be remotely located, but in communication with the vessels 40 during operation. [0148] The surfactant referred to herein should be a chemical or like substance for enhancing the performance of the fluid stream proppant, for aiding in the placement of the proppant into a formation's fracture network, and/or for reducing proppant flowback during production and embedment. The proppant should be any material suitable for achieving the desired fracturing, or “fracing” of a target formation. The preferred system of the present invention is specifically geared toward fracing a coal formation for enhancing gas production therefrom, and the desired proppant is a form of sand. The use of the terms “proppant”, “surfactant”, “front”, “back” and the like is not intended to limit the present system's use or operation, nor the scope of the invention. Further, when describing the invention, all terms not defined herein have their common art-recognized meaning. [0149] Referring now as well to FIG. 4 (showing the trailer 12 ) and FIG. 5 (omitting the trailer), a particular aspect of the system is the arrangement at the back of the trailer which has a means for directing/diverting a high pressure fluid stream 61 into the pair of pressure vessels 40 operationally arranged in parallel, and a means for metering/feeding proppant into the fluid stream. Specifically, a piping arrangement 60 below the vessels 40 has a first inlet 62 for receiving a desired fluid. In a preferred embodiment that fluid is nitrogen gas pumped under high pressure from a nitrogen source, such as a pumper truck. A first Y-shaped diverter 64 downstream of the inlet splits the incoming nitrogen 61 into first and second fluid streams 66 , 68 respectively. An adjustable venturi-type orifice 70 downstream of the diverter 64 is adapted to create a pressure drop, say in the range of 300 psi (or other desired amount), in the second fluid stream 68 passing therethrough. The orifice 70 should have the effect of diverting more volume of fluid into the first stream than the second stream, and for maintaining a positive fluid pressure in the screw(s) 58 , as will become apparent later. The second fluid stream 68 then proceeds under relatively lower pressure toward a first outlet 72 for discharge to a coiled tubing rig or like apparatus in communication with the target formation. [0150] A second four-way diverter 74 downstream of the diverter 64 allows the first fluid stream to split again into first and second fluid sub-streams 76 and 78 respectively. Elongate piping 80 carries the second sub-stream 78 toward the top of the vessels, while the first sub-streams 76 are directed to the bottom of the vessels through respective first valves 82 . If only the left vessel is operating, then only the left valve 82 (as viewed in FIG. 5 ) is open for fluid entry, and the right valve 82 is closed, and visa versa. If both vessels are operating, then both valves 82 should be open. A third T-shaped diverter 84 further splits the second fluid sub-stream 78 into third fluid sub-streams 86 directed to the top of the vessels through respective second valves 88 . The diverter 84 and valves 88 also act as a pressure equalization manifold between the vessels 40 . Further, the piping 80 and associated valves 82 , 88 and 90 (discussed below) are used to equalize the fluid pressures at the top and bottom of the vessels 40 , and to de-pressurize the system to atmosphere when required. [0151] Each pressure vessel 40 is formed by an elongate cylindrical tank having relatively thick outer walls 42 (e.g. 5 inches solid steel) to accommodate the high operating pressures (up to 9000 psi/63 MPa or more). The walls form an elongate interior cavity or chamber 44 for holding the desired proppant. The proppant is introduced into the chamber through a first vessel inlet 46 (shown in FIG. 2 ) at a first top end 48 of the vessel. A second vessel inlet 50 is provided at the top end of each tank for entry of the respective third fluid sub-streams 86 , and to communicate with a respective third pressure relief valve 90 for bleeding pressure from the respective vessel to atmosphere prior to receiving proppant through the proppant inlet 46 . A first vessel outlet 52 at the bottom of the vessel allows proppant and fluid to exit the vessel's chamber 44 and to encounter the first fluid sub-stream 76 , and to then proceed to the proppant metering means. It is noted that the identifiers such a “top” and “bottom” as used herein refer to the vessel in its generally vertically oriented operating position, as shown in FIGS. 2-5 , rather than when it is reclined about the pivot 34 by the hydraulic lift cylinders 32 into its generally horizontal transport position (as in FIG. 1 ). The vessels should be reinforced at 43 where they engage the hydraulic cylinders 32 and pivots 34 . [0152] The proppant metering means is defined by a high pressure sand screw 54 disposed generally perpendicularly to each vessel's longitudinal centerline and it's outlet 52 . Other orientations of the screws should also be suitable. The screw has a flanged radial inlet 56 for attachment to a respective flange 53 of the vessel outlet 52 , and for receiving the proppant and fluid therefrom. A variable rate electric or other suitable motor 58 operates the screw to discharge, or meter, a desired amount of proppant through a radial screw outlet 57 into piping 92 . A Y-shaped joint 94 allows the proppant and fluids exiting the screw 54 to enter the second fluid stream 68 prior to exiting the first outlet 72 . A pressure vessel isolation valve 96 on each piping 92 upstream of the Y joint 94 operates to isolate a respective vessel from the second fluid stream 68 as desired (e.g. when that vessel is inoperative and depressurized for proppant recharging), to prevent fluid backflow into the vessel through the screw. Each screw may be readily removed from the system for servicing, repair, or switching to a different screw size by uncoupling the flanges 53 , 56 at one end, and at the other end by uncoupling from the isolation valve 96 . [0153] The piping arrangement 60 further incorporates an “upstream” surfactant injection port 98 at the first inlet 62 for introducing surfactants from the delivery tubing 30 into the fluid stream 61 prior to its split into the first and second fluid streams 66 , 68 . Such introduction may also be accomplished further downstream after the fluid and proppant have been mixed, such as at a “downstream” surfactant injection port 99 located immediately prior to the first outlet 72 . Both ports 98 , 99 may also be used concurrently, and other ports may be added in the system if required. [0154] An alternate second embodiment of the present invention is shown in FIGS. 6 to 8 where the screws 154 are located longitudinally within the pressure vessels 140 . The reference numerals used in these figures are similar to those used to describe the components of the system 10 , with the addition of a prefix “1”. Each vessel has in essence three longitudinally aligned chambers. A first elongate chamber 144 a is defined by the vessel's outer wall 142 for holding the proppent received through the first vessel inlet 146 via the delivery line 130 . A pressure relief valve 190 bleeds excess pressure before filling the chamber 144 a . A second elongate chamber 144 b is longitudinally disposed within the first chamber 144 a in a parallel relationship, and houses the screw 154 operated by the motor 158 . The bottom end of the second chamber 144 b has a first bottom opening 145 into the first chamber 144 a to allow entry of the proppant. The screw raises the proppant to the opposed top end where it is discharges out of a second top opening 147 into the open end of a hollow third chamber 144 c . The third chamber 144 c is also located within the first chamber 144 a and extends downwardly alongside the second chamber 144 b and opens at a bottom vessel outlet 152 where the proppant and high-pressure fluid exit the vessel into the piping arrangement 160 . [0155] The piping arrangement 160 is similar to the piping arrangement 60 in that high pressure fluid, such as nitrogen gas, enters at the inlet 162 and is divided into first and second fluid streams 166 and 168 with the aid of orifice 170 . The first fluid stream is then directed to one or both vessels at the Y-shaped diverter 167 by controlling the first valves 183 . The first fluid stream enters the bottom of the first chamber 144 a via the second vessel inlet 150 . The pressurized fluid is urged through the proppant and up the screw where it proceeds through the top opening 147 and then down the third chamber 144 c to exit the bottom outlet 152 . When the screw is activated to discharge proppent through the top opening 147 , the proppant is entrained in the high-pressure fluid flow and is carried down the third chamber 144 c to the outlet 152 . The fluid and proppent exiting the outlet 152 proceed through piping 192 and the respective pressure vessel isolation valve 196 to rejoin the second fluid stream 168 moving to the first piping outlet 172 . [0156] This system is not preferred over the first embodiment for several reasons. First, for a given size of pressure vessel, the vessel 140 holds less proppent than the vessel 40 since internal volume is lost to the second and third chambers 144 b , 144 c . Second, a longer and more costly screw must be employed in the vessel 140 , and such screw is more difficult to access or remove than in the first embodiment. The screw 154 must lift proppent against gravity, whereas the negative effects of gravity are reduced in the arrangement of the first embodiment. [0157] The operation and advantages of the present invention may now be better understood, with reference to the first embodiment. For illustrative purposes it will be assumed that nitrogen and a form of sand are to be pumped into a coal formation. In the first embodiment, the rig is brought to the work site in an advantageous reclined transportation mode (as in FIG. 1 ) to avoid road clearance limitations. The trailer's wheel configuration is also designed to make the rig “road legal”, despite the extremely heavy weight of the system 10 . [0158] The vessels 40 and associated components are then elevated into the operating mode ( FIG. 2 ) for use. If the vessel chambers 44 require charging with sand, then it is pumped from the tank 20 into at least one of the chambers via the line 26 and through respective first vessel inlet 46 . An advantage of this two vessel arrangement is that fracing may commence once one vessel is charged with sand. There is no need to wait for the second vessel to be filled to begin operations. Likewise, there is no need to disrupt ongoing operations once the first vessel is emptied of sand since pumping may readily switch to the second filled vessel. In the meantime, the first vessel can be refilled with sand and be ready for when the second vessel is emptied. In unusual circumstances where the rate and volume of sand injection requires both vessels to operate simultaneously, then operations may be disrupted periodically while the vessels are refilled. [0159] Assuming that the left vessel 40 in FIG. 5 is charged and ready for operation, and the right vessel is not, then the operator should isolate the right vessel by closing the first and second valves 82 , 88 leading to the right vessel, as well as the respective (right side) isolation valve 96 . Conversely, the first and second valves 82 , 88 and the isolation valve 96 for the left vessel should be opened or activated. Once a high-pressure nitrogen stream 61 is established from a nearby nitrogen truck into the first inlet 62 , the orifice 70 should provide the necessary pressure drop and split into first and second nitrogen streams 66 , 68 . The first stream is then further split into the first nitrogen sub-stream 76 at the lower end of the vessel and into the third nitrogen sub-stream 86 which enters the vessel at the top. The first and second valves 82 , 88 control the relative pressures of the nitrogen gas to ensure that the nitrogen moves downwardly through the sand in the chamber 44 and does not reverse to force the sand upwardly, particularly as the sand is being depleted in the vessel. Both gravity and the nitrogen flowing out of the vessel should urge the sand from the chamber 44 toward the screw 54 . If the screw is not activated, the nitrogen should seep through the porous sand and around the stationary screw blades to escape out of the screw outlet 57 . However, once the screw is activated to carry sand to the screw outlet 57 , the sand should be carried in the fourth nitrogen sub-stream 87 to the (unsanded) second nitrogen stream at the Y-joint 94 , where both streams commingle and exit the first outlet 72 to a coiled tubing rig and ultimately to the coal formation. [0160] If desired or required, surfactants may be introduced at either one or both of the upstream and downstream injection ports 98 , 99 . Injection at the downstream port 99 avoids circulation of the surfactant through the vessels and most of the system 10 . In contrast, injection into the relatively “dry” nitrogen stream at the upstream port 98 will “wet” the sand in the vessels. [0161] This nitrogen and sand combination, mixed potentially with one or more surfactants, should enhance the stimulation of coal deposits for improved gas production over prior art methods, as discussed earlier. [0162] It is noted that pressure gauges 36 and one or more densometers 38 are installed at selected locations in the system to monitor pressures and proppant concentrations in the fluid stream exiting the system, to ensure that the desired volume and rate of proppant is being delivered to a particular formation. In particular, the gauge 36 a measures the manifold inlet pressure to the screw 58 , and the gauge 36 b measures the manifold outlet pressure near the outlet 72 . If the exiting fluid stream is not satisfactory, then the orifice 70 and/or the various described valves and/or the speed of the screw(s) 58 for proppant delivery may be adjusted, either manually or preferably remotely by PLC (programmable logic controller) systems, to obtain the desired mix/values. [0163] Further advantages of the present invention include: the system provides great flexibility for various pumping operations; the system allows for a wide range of proppant density in the fluid stream; the system can use various types of proppant; the system's ability to mix proppant in the fluid stream, and in particular to mix sand with a N 2 gas stream, provides an important means of enhancing production of coal bed methane sales gas; the system is cost effective to build and operate; and, the trailer 12 carrying the system 10 is “street” (i.e. weight) legal. [0170] An even more advantageous third preferred embodiment of the present system is shown in FIGS. 9 and 10 . In general, the system of this embodiment in essence functions the same way as the first embodiment, except that the vessels 240 have a spherical configuration rather cylindrical. The reference numerals used for this embodiment are similar to those used to describe the components of the system 10 , with the addition of a prefix “2”. There are several advantages to employing such spheres, including: [0171] The sphere is a more efficient shape for confining contents under high-pressure; [0172] A greater volume of proppant may be held than in a given cylindrical configuration; and, [0173] The spherical configuration omits the need for separate operating and transporation modes. For holding a given volume of proppant, the sphere 240 need not be as tall as the cylinder 40 (when elevated in an operating position), and so the sphere provides a more advantageous road height clearance when mounted on the trailer. Hence, the spheres 240 are mounted in a single orientation on the trailer for both transport and operation, and need not be reclined for transportation nor inclined for operation as the cylindrical vessels 40 . [0174] Each spherical pressure vessel 240 has a sand screw 254 located therebeneath in a manner similar to the first embodiment, and the piping system for proppant and nitrogen gas delivery is also similar. However, the location of certain features on the trailer 212 have changed, such as placement the proppant storage tank 220 and the surfactant storage and high pressure pumping assembly 228 at the rear of the trailer. Each sphere 240 also has a plurality of legs 231 spaced about a bottom portion thereof for supporting the sphere on the trailer, and three valves 280 at a top portion thereof for connection to respective piping for delivery of proppant, for delivery of nitrogen gas, and for venting. [0175] A fourth embodiment of the invention in FIG. 11 shows a trailer carrying a single spherical pressure vessel 340 which is of a similar design to the third embodiment. Some of the reference numerals used for this embodiment are those used to describe like components of the system 10 , with the addition of a prefix “3”. The vessel's mounting assembly differs from the previous lower legs 231 in that retractable arms 311 are employed to engage a top portion of the sphere to hold it on the trailer. Also, the vessel has a single cap 341 which accesses the sphere's interior and operatively connects to the proppant and nitrogen gas supplies, and has a vent. Valves in either the cap, or in piping leading to the cap, control the flow of products into the sphere, and for venting of the vessel. Further, the auger 354 in this embodiment is inclined for better ground clearance. A drive motor and seal assembly 354 (shown in outline) is coupled to the upwardly inclined end of the auger to operate the auger. [0176] It is noted that a configuration of a single vessel per trailer is not preferred as it will present certain disadvantages. If the capacity of the one vessel is insufficient to treat a particular formation, then fracing operations will have to be disrupted as the vessel is refilled with proppant. [0177] A sample operating sequence of the fourth embodiment will now be set out, with reference to FIGS. 12-16 which show the vessel 340 and associated piping 360 in isolation from the trailer. The sequence is described for one pressure vessel, but is equally applicable to each vessel of a multi-vessel configuration: [0178] Lower valves (such as the auger outlet valve 396 ) under the spherical pressure vessel are closed. The sand screw, or auger 354 , is off (inoperative). The pressure vessel 340 is empty and unpressurized. [0179] The top proppant supply and vent valves 346 , 390 are opened and proppant is blown or pumped into the vessel until nearly full. [0180] The top supply and vent valves 346 , 390 (capped at 391 ) are closed. [0181] The top fluid (nitrogen) valve 388 is opened and the pressure vessel is pressurized up to the line pressure of the main horizontal fluid line 361 running along the bottom of the trailer. In this embodiment the vessel has a pressure rating up to about 9000 psi, and a proppant capacity of about 5 tonnes. [0182] The outlet valve 396 at the end of the auger 354 is opened and the fluid (nitrogen) bypass line valve 382 at the auger outlet is opened. This flow of fluid (nitrogen) clears the auger outlet 357 . [0183] The auger is started to bring proppant from the pressure vessel to the outlet 357 of the auger. [0184] Since the top and bypass fluid (nitrogen) valves 388 , 382 are open, the high-pressure flow of fluid (nitrogen) assists the flow of, namely helps push, the proppant through the auger. [0185] Once the pressure vessel is empty, the top fluid (nitrogen) valve 388 is closed, then the auger 354 is stopped, then the bypass fluid (nitrogen) line 382 is closed and then the auger outlet valve 396 at the discharge 357 of the auger is closed. [0186] At this point the pressure vessel is vented down to atmospheric pressure via the vent valve 390 and/or purge valve 393 (& associated choke 395 ) and then refilled with proppant, and the above sequence is repeated. [0187] The fluid stream, namely all or mostly nitrogen, in the main fluid line 361 across the bottom of the trailer is pumped at very high pressure. With the use of in-line restrictors, a portion of the fluid stream is diverted (via the first diverter 364 ) to the pressure vessel's top fluid inlet port 350 and to the auger fluid by-pass line 376 (via the second diverter 374 ), and another portion to the auger outlet bypass 394 , in a like manner to that shown in FIG. 5 for the first embodiment. After the first diverter 364 there is an inlet 399 for the surfactant where it is injected at high pressure into the fluid (nitrogen) stream in the main line 361 . After this injection point there is an auger outlet by-pass 394 for discharging the proppant and combining it with the fluid stream in line 361 . The resulting fluid stream at the outlet 372 of this line (analogous to the the first outlet 72 in FIG. 5 ) contains a mixture of nitrogen, suspended surfactant and proppant for use in a target formation. [0188] The above description is intended in an illustrative rather than a restrictive sense, and variations to the specific configurations described may be apparent to skilled persons in adapting the present invention to other specific applications. Such variations are intended to form part of the present invention insofar as they are within the spirit and scope of the claims below. For instance, it may be possible to employ only one cylindrical vessel 42 per trailer, as in the FIG. 11 embodiment, but the single vessel configurations present certain disadvantages. If the capacity of the one vessel is insufficient to treat a particular formation, then fracing operations will have to be disrupted as the vessel is refilled with proppant. Likewise, three or more pressure vessels might be employed per trailer, but it is believed that the third vessel would be redundant, be cost inefficient, and would lead to weight restriction issues for the trailer. Any number of trailers with pressure vessels mounted thereon may be employed in series or parallel at a given site, but capacity and cost efficiency are among the factors that will dictate the optimal configuration. It should also be appreciated by those skilled in the art that, based on the above information, other vessel shapes may also provide suitable proppant storage and pressure capacities.

A high-pressure injection proppant system for stimulating coal bed methane production preloads proppant, such as sand, into one or more high-pressure vessels, for delivery into a fluid stream, such a N 2 gas stream. A screw auger arrangement meters the proppant volumes and rates into the fluid stream. Two such vessels operationally mounted in parallel can function separately or concurrently depending on the demand for proppant in a particular formation. The system provides for the injection of surfactants into the fluid stream to enhance the performance of the proppant, to aid in the placement of the proppant into a fracture network, and to demote proppant flowback during production and embedment. The system can be operated manually or by computer automation to aid in the accuracy of the mixing of the fluid stream components.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION [0001] The present invention relates to shutters and in particular to shutters of the roller type having improved resistance to storms and break-ins. It furthermore relates to a device for securing such shutters against storm damage. DESCRIPTION OF RELATED ART [0002] Shutters or blinds for windows, doors and other apertures are generally known. A common design for such shutters is the so-called roller shutter. Such roller shutters generally comprise a number of horizontally extending slats, articulated to one another to form a curtain. The curtain may be provided with a roller, usually located at the upper edge of the window, around which the curtain may be wound to raise it or lower it. The lateral edges of the curtain will usually be guided by vertically extending guides attached to the lateral edges of the window aperture. Guiding may be achieved by lateral extremities of some or all of the slats extending into a U-shaped channel within the guide. Other similar arrangements to provide effective guiding are also known. [0003] Simple guiding arrangements may suffice for internal blinds or shutters for the purpose of preventing light, or for light-duty external shutters. For shutters intended to be resistant against strong winds, break-ins or other damage, further measures are required. [0004] It is also known to provide shutters with additional security means in the form of storm bars, which can be applied vertically across either or both faces of the shutter to provide additional support. Such storm bars are both unsightly and inconvenient and require substantial space. Often, due to the size of the storm bar, the frame of the aperture must be further built out to provide sufficient clearance. Furthermore, since they are often only applied in readiness for a storm or when “shutting up at night”, they may sometimes be absent when required, e.g. in the event of an unexpected storm. Likewise, conventional storm shutters lack a horizontal element other than the retracted, coiled shutter, and for use of conventional storm shutters, vertical supports must further be installed, often at great difficulty and requirement of extensive hardware. The vertical supports commonly used in connection with a conventional storm shutter may require significant building out of the frame of the aperture or even beyond the frame of the aperture. [0005] Arrangements have been suggested for increasing the storm resistance of shutters by providing wind-lock elements at the ends of some or all of the slats. The wind-locks may be in the form of T-shaped elements or other protuberances, which locate in C-shaped channels in the lateral guides. In order for sliding of the slats within the lateral guides to take place without jamming, there must be clearance between the wind-lock elements and the guides. Under storm conditions, this clearance allows the slat to bow inwards and outwards before it is restrained by the wind-locks. Such bowing is both undesirable and unacceptable, as it may result in breakage of the window or door the shutter was installed to protect. A device of this nature is known from U.S. Pat. No. 5,839,493 to Quasius. SUMMARY OF THE INVENTION [0006] According to the present invention, resistance to high winds and other forces may be achieved without the above-mentioned disadvantages by the use of a high-strength wire or cable tensioned across the building aperture to provide support to the shutter. There is thus provided a shutter for a building aperture comprising a shutter curtain having a first and a second face, the shutter curtain being locatable in the aperture, a filament spanning the aperture and lying in a plane substantially parallel and adjacent to the first face of the shutter curtain and a tensioning device for applying tension to the filament to provide support to the curtain against flexure thereof. [0007] Advantageously the filament comprises a metallic wire of high modulus of elasticity, in particular a stainless steel or high strength alloy wire. Alternatively, the filament may comprise a high strength fiber cable of low extensibility such as the carbon fiber cords used in the rigging of sailing boats. In addition, the filament may be any flexible strengthening means comprising a wire, cable, chain, or elongated support having sufficient flexibility to be wound around the tensioning device. [0008] To ensure easy deployment and tensioning of the filament, the tensioning device may comprise a winch. The winch may comprise a locking element such as a ratchet, for selectively locking the winch against unwinding. Alternatively, the tensioning device may be a lever or cam element which tensions and locks the filament by pivoting about a fixed point. As a further alternative, the shutter curtain may itself provide tensioning of the filament as the shutter curtain is flexed or bowed by the pressure or vacuum forces induced by high winds. The shutter curtain may act as the tensioning device either alone or in combination with an additional tensioning device as above described. [0009] The shutter may be of a generally standard form comprising first and second guides or sidetracks which respectively receive and guide opposing lateral edges of the curtain, the guides being located on opposing lateral edges of the aperture. A first end of the filament may then be retained on the first guide and a second end of the filament retained by the tensioning device provided on the second guide. Alternatively, a retaining element such as a hook or loop may be provided on the second guide with the filament passing around the retaining element and being received by the tensioning device attached to the first guide. [0010] In order to provide further support to the shutter curtain, according to a further aspect of the invention a plurality of retaining elements may be provided in a distributed fashion over the length of both guides and the filament may be laced around the retaining elements such that it crosses the shutter curtain a number of times. For such an arrangement, the tensioning device must be capable of removing a greater amount of slack than is the case with a shorter filament which crosses the shutter a single time. [0011] Where a plurality of retaining elements is provided, these may be either fixed or slidably mounted to the first and second guides. Alternatively, they may be mounted to the structure surrounding the aperture either directly or indirectly. [0012] In a further alternative embodiment of the present invention a second filament may be provided to support the shutter curtain. The second filament may be provided with a second separate tensioning device or both filaments may be tensioned in parallel using the same device. In order to provide support against forces applied to both faces of the shutter (or acting in both directions), if the first filament is located adjacent to a first face of the shutter curtain, the second filament may be located in a plane substantially parallel and adjacent to the second face of the shutter curtain. Alternatively or additionally, further filaments may be provided adjacent to the same face of the shutter. [0013] According to a desirable embodiment of the invention, a storage device may be provided for conveniently storing at least part of the filament when not under tension. Such a storage device may be a reel or may be provided by a cavity within the guides. The storage device may comprise an elastic element biasing the filament in a direction into the storage device. [0014] According to a further aspect of the present invention, and particularly for use in conjunction with existing shutters, there is provided a storm retainer for retaining a shutter curtain against flexure, the shutter curtain being located across an aperture, the storm retainer comprising a filament; an anchor attached to a first portion of the filament and securing the first portion with respect to the aperture; and a tensioning device, the tensioning device being secured with respect to the aperture and being attached to a second portion of the filament wherein actuation of the tensioning device causes tensioning of the filament from the first portion to the second portion. [0015] In a particularly advantageous embodiment of the present invention, there is provided a shutter for a building aperture comprising a plurality of slats articulated to one another to form a shutter curtain, at least one of the slats having a hollow interior. Lateral guides are located on opposite sides of the building aperture, each lateral guide having a channel serving to guide the curtain for sliding motion along the guides. A filament extends through the hollow interior of the at least one slat, the filament having first and second ends and a wind-lock is attached to each of the first and second ends of the filament, extending into the channels of the guides. Restraining elements are located within the guides, the restraining elements preventing removal of the wind-locks from the channels. In order to tension the wind-locks against the restraining elements a tensioning device is provided for selectively applying tension to the filament. Such a device does not require separate storage of the tensioning filament since it remains effectively out of sight within the slat. Nevertheless, by providing for selective tensioning of the filament to lock the wind-lock within the guides, these can be subsequently released to allow for rolling up of the shutter curtain without snagging and jamming of the wind-locks. Various tensioning devices may be used to provide such selective tensioning. [0016] The filament may comprise two filament sections joined by a turnbuckle, rotatable to draw the two filament sections together. Alternatively, a pivotable lever clamp may be provided to draw the two filament sections together. [0017] In addition to the use of a shutter curtain having slats, it is also within the scope of this invention to employ a rigid panel supported by a filament as a covering to a building aperture. In the use of a rigid panel, such as one made of plywood, acrylic, polycarbonate, or thin metal, the filament may be laced through various apertures in the panel at a favorable orientation. In the alternate, the filament and panel could be bolted or otherwise together affixed to the building. The panel may have a plurality of holes around its perimeter so that a user may affix the panel to the building aperture wherever an opportunity exists to do so, without the need to drill more holes. A particularly useful filament for this embodiment of the invention is the Stake Eye cable, commercially produced by Loos & Co., available in a variety of sizes according to the user's need. One advantage of using a filament to support a rigid panel would be that the additional support provided by the filament could allow use of a thinner rigid panel or a less corrugated rigid panel than would be required without the use of a filament. A decrease in panel thickness or corrugation would make the panels lighter in weight. When panels are made of translucent or transparent materials, a decrease in thickness or corrugation would improve visibility through the panel and also would allow more light to penetrate the building than with a thicker material. [0018] The invention also provides for a method of restraining a shutter provided in a building aperture against flexure, the method comprising providing a substantially inextensible filament, disposing the filament across the aperture to lie substantially in the plane of the shutter and applying tension to the filament. DESCRIPTION OF THE FIGURES [0019] Embodiments of the invention will now be explained in further detail by way of example only with reference to the accompanying figures, in which: [0020] FIG. 1 is an elevation of a window aperture including a storm retainer according to a first embodiment of the invention; [0021] FIG. 2 is an elevation of a window aperture including a storm retainer according to a second embodiment of the invention; [0022] FIG. 3 is a partial horizontal sectional view of a third embodiment of a storm retainer according to the present invention; [0023] FIG. 4 is a partial view of a retaining arrangement for the device according to FIG. 3 , taken in the direction B-B; [0024] FIG. 5 is a detailed view of the tensioning device of FIG. 3 ; [0025] FIG. 5B is a detailed view of an alternative tensioning device to that of FIG. 5 ; [0026] FIG. 6 is a partial horizontal sectional view of a fourth embodiment of the present invention; [0027] FIG. 7 is a side cross-sectional view through a shutter assembly according to the present invention; [0028] FIG. 8 is a side cross-sectional view through an alternative shutter assembly to that of FIG. 7 ; [0029] FIG. 9 is a detail cross-sectional view along direction C-C of FIG. 8 ; [0030] FIG. 10 is an elevation of a window aperture including a storm retainer according to a fifth embodiment of the invention; [0031] FIG. 11 is a side view of a sixth embodiment of the present invention; [0032] FIG. 12 is a partial horizontal sectional view of an alternative shutter assembly to that of FIG. 6 ; [0033] FIG. 13 is an elevation of a window aperture including a storm retainer according to an alternative to the embodiment of FIG. 1 ; [0034] FIGS. 13 a and 13 b depict a horizontal sectional view of the embodiment of FIG. 13 under conditions free from wind pressure and conditions of wind pressure, respectively; and [0035] FIG. 14 depicts an elevation of a seventh embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION [0036] FIG. 1 illustrates a first embodiment of the present invention, applied to a window aperture 1 . For the sake of clarity, details of the window itself are not shown. In the following description, reference will be made interchangeably to window and aperture. Although reference is made to a window, this is also intended to include doors, roof lights, French windows and any other openings in a building or structure for which it may be desirable to provide additional storm security. [0037] Aperture 1 is provided with a pair of guides 3 , 4 located on opposite lateral edges of the aperture 1 . Guides 3 , 4 serve to guide motion of a shutter curtain 10 , which may be raised or lowered by a suitable mechanism (not shown) to selectively cover the aperture 1 . The shutter curtain 10 may be a roller shutter of otherwise standard configuration formed of a plurality of slats 12 articulated together, whereby the curtain may be rolled up within a shutter casing 14 . [0038] According to a first aspect of the present invention, an anchor 20 is attached securely to guide 4 adjacent to an upper left-hand corner of the aperture 1 . A filament 22 is attached to the anchor 20 and crosses the aperture 1 diagonally to a second anchor 24 located adjacent to the lower right-hand corner of the aperture 1 . The second anchor 24 is located on a lever 26 pivoted to the guide 3 at a pivot point 28 . By clockwise rotation of the lever 26 in the direction of the arrow A, the filament 22 may be tensioned. A locking pin 30 is provided for insertion into a suitable hole in the guide 3 to maintain the lever 26 in the tensioned position. [0039] By appropriate tensioning of the filament 22 between anchors 20 and 24 , a lateral deflection of the mid-point of the filament 22 may be reduced to an amount dependent upon the modulus of elasticity of the filament 22 and the lateral force applied. Use of filaments made from high-modulus materials such as steel wire, in particular stainless steel or carbon-fiber cord has been found to be particularly advantageous. Other materials having similar properties of flexibility, strength and lightness may also be considered. [0040] In contrast to prior art systems which require sturdy metal bars to be placed across the shutters to provide support, the device according to the present invention is extremely lightweight and can be easily deployed and conveniently stored when not required. The anchor 20 , which may also be in the form of a hole or slot directly in the guide 4 itself, can be left in place, while filament 22 and lever 26 can be removed for storage. Conveniently, the lever may be arranged so that the filament can be wound around it for storage. Pivot point 28 and locking pin 30 may be removed or left in place as desired. Alternative storage possibilities for the filament 22 may also be provided, thus the filament 22 may be concealed within a hollow internal channel within the guide 4 and extended to a fixed stop only when needed. Elastic retraction means such as a spring or elastic cable could be provided within such a channel to facilitate retraction of the filament when not in use. [0041] Once the filament 22 is tensioned across aperture 1 , forces on the shutter curtain 10 tending to push it against the filament 22 will be resisted by the elastic deformation of the filament 22 as well as by the support provided around the periphery of the curtain 10 by the guides 3 , 4 . In an alternative to the use of a tensioning device, FIG. 13 depicts the shutter curtain 10 in combination with guides 3 and 4 , anchors 20 and 20 ′, and filament 22 . Not shown is an optional second filament 22 ′ located on the opposite side of the shutter curtain. Tensioning of filaments 22 and 22 ′ across aperture 1 may occur even without the use of a tensioning device, through the pressure and vacuum forces of high winds, as depicted in FIGS. 13 a and 13 b. [0042] The shutter curtain 10 may optionally be provided with a hook element 32 through which filament 22 may be threaded or looped. Hook element 32 is preferably recessed into one of the slats 12 forming the curtain 10 to prevent it from interfering with the rolling up of the curtain 10 . By passing the filament 22 through the hook element 32 , the filament 22 may also serve to resist forces on the shutter curtain 10 in a direction tending to push it away from the filament 22 . This is particularly important since storm shutters must be capable of resisting both pressure and vacuum forces induced by high winds. [0043] It will be evident to the skilled man that alternative forms of hook element 32 may be provided and that, instead of a single element, numerous such elements could be provided along the course of the filament 22 . Alternatively or additionally, a second filament together with appropriate anchoring and tensioning devices may be provided on the other face of the shutter curtain 10 , whereby the shutter curtain is effectively sandwiched between two tensioned filaments, as depicted in FIG. 11 . [0044] FIG. 2 discloses a second embodiment of the present invention in which like numerals are used to denote the same elements as in FIG. 1 . According to FIG. 2 , aperture 1 is provided with a shutter casing 14 into which the shutter curtain 10 has been retracted. In this embodiment, in order to provide greater support for the curtain 10 , guides 3 , 4 are provided with a number of retainers 34 distributed between them. Filament 22 is attached to anchor point 20 at the upper left-hand corner of the window and passes in turn around the retainers 34 in a zigzag manner. To aid in the attachment of the filament 22 around the retainers 34 , the retainers 34 are open on one side (not shown) in the form of a hook. In this way, the filament may be looped around them in the manner of lacing up mountaineering boots. As an alternative to such hooks, retaining loops or eyes could be used whereby the filament would be threaded sequentially through each loop or eye. At the lower right-hand corner of the aperture 1 , a winch 36 is provided. Winch 36 is a conventional ratchet operated device around which the filament 22 may be wound. Suitable connection means (not shown) are provided at the free end of the cable to assist connection to the winch 36 . Actuation of the winch 36 causes the filament 22 to be tensioned and the ratchet mechanism allows it to be locked in place. The tensioned filament 22 serves to support the shutter curtain in substantially the same way as in the embodiment of FIG. 1 . [0045] Advantageously, the winch 36 may serve to wind up the filament 22 when not in use and may then be removed for storage. In order to ensure equal tension along the length of the filament 22 , bearings (not shown) may be provided to reduce frictional forces between the filament 22 and the retainers 34 . The bearings may be in the form of a lubricated surface such as PTFE on either the filament 22 or the retainers 34 or both. Alternatively, the retainers 34 may be provided with roller or pulley-type elements over which the filament 22 is passed. As in the case of FIG. 1 , a second filament and tensioning arrangement may be provided for the other face of the shutter. [0046] Other methods of storing and deploying the cable may also be used. While the retainers 34 of FIG. 2 are shown in fixed locations, they may also be arranged to slide in grooves formed in the guides 3 , 4 . When not in use, the retainers 34 and filament 22 may be slid upwards for storage at the upper edge of the aperture, any resulting slack in the filament 22 being taken up by an appropriate retraction mechanism as described above. [0047] In the embodiments of both FIG. 1 and FIG. 2 , the anchor 20 and the tensioning device (lever 26 or ratchet 36 ) have been located on the guides 3 , 4 . According to the present invention, these elements as well as the retainers 34 of FIG. 2 may also be located independently of the guides, either affixed directly to the structure forming the aperture or forming part of a separate element to be located adjacent to the guides 3 , 4 . Such a configuration may be beneficial in situations where it is desired to retro-fit storm protection according to the present invention to existing shutters. [0048] A further embodiment of the present invention is shown in FIGS. 3 to 5 in which once again like numerals are used to denote the same elements as in FIG. 1 . FIG. 3 shows a partial horizontal sectional view through a shutter, showing generally C-shaped guides 3 , 4 . Guides 3 , 4 are securely attached to the outside face of a wall 17 by suitable bolts 18 or other appropriate fastening means. The guide 4 includes front and rear profiles 38 , 38 ′ between which a slot 39 is provided in which the shutter curtain 10 may slide. Front and rear nuts 40 , 40 ′ are securely supported within the front and rear profiles 38 , 38 ′ respectively and attached to front and rear filaments 22 , 22 ′. For this purpose, each filament 22 , 22 ′ is provided with a tensioning device in the form of a knob 42 , 42 ′ with threaded extension 44 , 44 ′. The threaded extensions 44 , 44 ′ locate within threaded bores of nuts 40 , 40 ′. At the other extremity of both filaments 22 , 22 ′, front and rear anchors 20 , 20 ′ are provided for retention by guide 3 , as will be described below. [0049] FIG. 4 is a partial side view of a section of guide 4 , taken in direction B-B of FIG. 3 . FIG. 4 shows how nuts 40 , 40 ′ are retained within profiles 38 , 38 ′ by means of keyhole-shaped slots 46 , 46 ′. As can be seen from the dotted profile of nuts 40 , 40 ′, the nuts 46 , 46 ′ are sized to fit through the larger portions 48 , 48 ′ of slots 46 , 46 ′ and to lock in the downwardly extending narrow sections 50 , 50 ′. From FIG. 4 , it can also be seen how the square-shaped head of the nut 40 (shown partially in broken lines) prevents the nut 40 from rotating within the profile 38 when the knob 42 is rotated. Anchors 20 , 20 ′ are retained in a similar manner in similar slots provided in the guide 3 . In this manner, filaments 22 , 22 ′ are easily removed, when desired, for storage. [0050] In use, when it is desired to secure the aperture against storm damage or break-in, a filament 22 is retrieved from storage and anchor 20 is located within the locating slot provided in guide 3 . Then, the filament 22 is extended across the aperture and the nut 40 is located within slot 46 as described above. Knob 42 is then threaded inwardly to move threaded extension 44 into the nut 40 to cause the filament 22 to be tensioned. Because of the high modulus material used for the filament 22 , the filament 22 is very inextensible and sufficient tension may be achieved with little relative movement between the threaded extension 44 and the nut 40 . A similar procedure is then followed for filament 22 ′. [0051] FIG. 3 illustrates the position in which filament 22 ′ has been tensioned by advancing threaded extension 44 ′ through nut 40 ′, while filament 22 is still relatively slack. The arrangement of the filaments may be conducted with the shutter curtain in the raised position. Once the filaments are in place and tightened, the shutter may be slid down along the slot 39 through the gap separating the filaments 22 , 22 ′. [0052] FIG. 5 illustrates in further detail the construction of one of the tensioning arrangements of FIG. 3 . In order to attach the filament 22 to the knob 42 , the threaded extension 44 is provided with a hollow bore 52 through which the filament 22 extends. The extremity of the filament 22 carries a spherical terminus 54 having a diameter slightly larger than the inner diameter of bore 52 . When tension is applied to the filament 22 , terminus 54 seats against the end of threaded extension 44 but allows rotation between the two surfaces. In this way, twisting of the filament 22 on rotation of knob 42 is prevented. [0053] An alternative arrangement for retaining and tensioning the ends of the filaments for the embodiment of FIG. 3 , is illustrated in FIG. 5B . According to this embodiment, instead of the keyhole shaped slots 46 , 46 ′, the profile 38 is provided with a threaded nut or insert 45 , securely attached by welding, adhesives or otherwise to the face of the profile 38 . FIG. 5B shows in detail the threaded extension 44 , which in this construction requires no nut, since it can be screwed directly into the insert 45 . It is to be noted in FIG. 5B , that the spherical head 54 of the filament 22 must be smaller than that of the embodiment of FIG. 5 , to allow insertion into the insert 45 . [0054] Although a single pair of filaments 22 , 22 ′ has been illustrated in the above embodiments of FIGS. 3 to 5 , it will be evident to the skilled man that further filaments may be provided at different positions over the height of the shutter. Similarly, although the illustrated embodiment is of horizontally disposed filaments, such filaments may also be arranged vertically between suitably located profiles along the upper and lower edges of the window aperture. The skilled man will also recognise further alternative ways of providing tension to the individual filaments. The tension may be provided by individual devices located either on the filament itself or on one or both of the guides. Alternatively, a single tensioning device may be used to tension all of the filaments (at least on one side of the shutter curtain) in parallel. As an example of such a system, it is envisioned that the profile 38 could be mounted for lateral movement with respect to e.g. the guide 4 . Movement of the profile 38 in a direction away from the opposite guide 3 would serve to tension any filaments attached between profile 38 and the guide 3 and could be accomplished by appropriate screw or camming devices. [0055] In the embodiments according to FIGS. 1 to 5 , the filament 22 has been disposed in a position adjacent to an outer face of the shutter curtain. According to a further embodiment of the invention, the filament 22 may be located within one or more of the slats 12 forming the shutter curtain 10 . FIG. 6 illustrates a partial cross sectional view of such a device including guides 3 , 4 , shutter slat 12 located in slot 39 and filament 22 . The slat 12 has a hollow interior 56 through which the filament 22 is threaded. Both extremities of the filament are provided with wind-locks 58 which prevent pullout of the slat from the slot 39 by engagement with restraining elements in the form of internal ribs 60 . In order to provide for tensioning of the filament 22 , a turnbuckle 62 is provided at an intermediate point along the filament 22 . The turnbuckle 62 may be of standard design and comprises left and right handed screw threads 64 , 66 whereby rotation of the turnbuckle causes the two ends of the filament to be drawn together. The turnbuckle 62 may be located in a recess 68 in the slat 12 , accessible only from the interior of the shutter, thereby enhancing security against break-ins. Other well-known devices for tensioning the filament 22 may be used instead of the turnbuckle 62 . Such devices may include lever action tensioning buckles or the like. Alternatively, the tensioning arrangement may be arranged to act on the wind-lock 58 by e.g. movement of one or both of the guides 3 , 4 or by the provision of movable restraining elements instead of the fixed internal ribs 60 as depicted in FIG. 12 . [0056] For the embodiment of FIG. 3 , where profiles are arranged on either side of a guiding slot, additional provisions may be required to ensure that the shutter operates correctly. FIG. 7 is a side cross-sectional view through a shutter assembly mounted onto the external face of the wall 17 of a building showing the shutter curtain 10 wound up inside shutter casing 14 . FIG. 7 also shows profiles 38 , 38 ′ mounted on either side of slot 39 and a number of keyhole shaped slots 46 , 46 ′ for receiving the nut of a storm retainer filament (not shown). The presence of profile 38 ′ means that the slot 39 is distanced from the wall 17 by a distance corresponding to the thickness of the profile 38 ′. In order to ensure that the shutter curtain 10 enters the slot 39 with minimum friction and without snagging, a roller 70 is located within the shutter casing 14 above the profile 38 ′. [0057] FIG. 8 illustrates an alternative arrangement to that of FIG. 7 , in which the shutter casing 14 is spaced from the wall 17 by a distance corresponding to the thickness of the profile 38 ′. In the illustrated embodiment, the profile 38 ′, itself serves as the spacer, extending upwards beyond the upper edge of the other profile 38 and the slot 39 . This is advantageously achieved by forming the guides 3 , 4 as two-piece extrusions as shown in FIG. 9 . FIG. 9 , which represents a cross-section taken along line C-C in FIG. 8 shows how the first profile 38 together with slot 39 are formed as a first element, while the second profile 38 ′ is separately formed as a second element. [0058] FIG. 10 discloses a fifth embodiment of the present invention in which like numerals are used to denote the same elements as in FIG. 1 . According to FIG. 10 , aperture 1 is provided with a pair of guides 3 , 4 located on opposite lateral edges of the aperture 1 . The aperture is also provided with a shutter casing 14 within which the curtain has been retracted. Separate filaments 22 , 22 ′, and 22 ″ are attached at one end to anchors 20 , 20 ′, and 20 ″, respectively, which are themselves attached to guide 4 . Filaments 22 , 22 ′, and 22 ″ are also attached at their other ends to anchors X, X′, and X″, respectively, which are, in turn, attached to guide 3 . Filaments Y and Y′ are attached transverse to filaments 22 , 22 ′, and 22 ″ such that the entire assembly of filaments forms a grid. Although FIG. 10 shows a grid assembly having three horizontal filaments and two vertical filaments, such an assembly could have varying numbers of horizontal and vertical filaments within the present disclosure. [0059] For the above embodiments, the guides 3 , 4 are preferably formed from metal or other high strength materials in order to withstand the forces applied to the shutter curtain 10 by high winds or during an attempted break-in. This is especially important in those cases where the anchors for the filament are provided on the guides themselves and tensioning takes place between the guides. Preferably, the guides are formed as extrusions of metal. High strength aluminium alloy has been found especially suited to this purpose. [0060] In the embodiment depicted in FIG. 14 , rigid panel Z is depicted in a building aperture wherein filaments 22 and 22 ′ are threaded through holes in the panel in a cross-wise configuration. [0061] Many further modifications in addition to those described above may be made to the structures and techniques described herein without departing from the spirit and scope of the invention. Accordingly, although specific embodiments have been described, these are examples only and are not limiting upon the scope of the invention.

A shutter for a building aperture comprising a shutter curtain having a first and second face, the shutter curtain being locatable in the aperture. The shutter further comprises a filament spanning the aperture and lying in a plane substantially parallel and adjacent to the first face of the shutter curtain and a tensioning device for applying tension to the filament to provide support to the curtain against flexure thereof in a direction towards the filament.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The invention relates to a sliding block guide for openable motor vehicle roofs, with a guideway which has one guide channel, and a sliding block which is movably guided in the guide channel along the guideway, the guideway being provided with at least one essentially linear guideway area and at least one bent guideway area. [0003] 2. Description of Related Art [0004] Sliding block guides of this type are known among others from German Patent DE 100 33 887 C1 and corresponding U.S. Pat. No. 6,568,750. In a first embodiment, a sliding block is permanently connected to respective carrier part and is essentially rhomboidal or cuboidal in the lengthwise cross section, its dimension in the horizontal direction being greater than its dimension in the vertical direction. The height (width) of an essentially horizontally running guideway area is matched to the vertical dimension of the sliding block, while the width of a guideway area, which runs steeply obliquely or vertically, corresponds to the horizontal dimension of the sliding block. In the transition area between these two guideway areas, the guideway width changes continuously from one value to the other. In a second embodiment, the sliding block has an oval shape in the lengthwise cross section and the guideway width is constant. In both cases, the curve handling capacity of the sliding block leaves something to be desired. The first embodiment is, moreover, structurally very complex. SUMMARY OF THE INVENTION [0005] A primary object of this invention is to devise a structurally relatively simple sliding block guide with good curve handling capacity of the sliding block. [0006] This object is achieved in accordance with the invention by a sliding block guide of the initially mentioned type which has a guide channel in the area of the curved areas of the guideway is made wider than in the area of the essentially linear guideway areas. [0007] The sliding block guide of the invention is characterized by improved curve handling capacity with reduced wear. It avoids or reduces at least unwanted rattling noise. In particular, the widening of the guide channel in the curve areas of the guideway is dimensioned such that the sliding block conforms to the guide channel walls essentially without deformation when these curve areas are traversed. [0008] The desired curve handling capacity of the sliding block can be further improved by the sliding block being pivotally supported. [0009] Preferably, the execution is such that the sliding block has a rubber-elastic sliding block body and a sliding cap which is seated on the sliding block body, and a carrier part is inserted in the rubber-elastic sliding block body which has a higher strength and stiffness than the sliding block body and is pivotally supported for its part on the support pin. [0010] The carrier part can be made of high-strength plastic or of metal. Preferably, the support pin is made of metal and is injection-coated with the plastic which forms the carrier part so that the carrier part can turn without play on the support pin from the start. Optionally, the carrier part can also be injection molded separately and can be clipped on the support pin. [0011] The carrier part for highly loadable support of the sliding block body and the sliding cap can have a hub which surrounds the carrier pin and two wings which project essentially radially from opposing sides of the hub. [0012] The sliding block body is preferably made essentially cap-shaped with a peripheral wall and an end wall which adjoins one side of the peripheral wall and is slotted in the area of its peripheral wall, the slots extending feasibly in the lengthwise direction of the sliding block and/or in the transverse direction of the sliding block. [0013] The sliding block can have an essentially cuboidal shape and is made mirror-symmetrical both in the lengthwise direction and also in the transverse direction. [0014] The sliding cap is preferably clipped onto the carrier part, and in the interest of high stability, is connected essentially without play to the carrier part in the lengthwise direction of the sliding block. For the carrier part it can have especially a peripheral wall, with the carrier part resting against its inside in the area of the narrow sides of the sliding block, since tolerance equalization is unnecessary in the lengthwise direction of the sliding block. [0015] However, preferably the sliding cap is elastically movable for especially effective tolerance equalization with reference to the carrier part both in the transverse direction of the sliding block and also in the rotary direction around the axis of the support pin. Here, the sliding block can have a peripheral wall, from the inside of which the carrier part lies at a distance in the area of the lengthwise sides of the sliding block. [0016] The rubber elastic sliding block body, advantageously, occupies essentially the entire space between the carrier part and the sliding cap. [0017] The sliding surfaces of the sliding cap which slide-engage the walls of the guide channel, preferably, as is known from German Patent DE 100 33 887 C1 and corresponding U.S. Pat. No. 6,568,750, integrate stripping lips which run obliquely relative to the displacement direction and eliminate dirt particles which can have penetrated into the sliding block guide during operation. [0018] The invention is explained in detail below with reference to the accompanying drawings by way of example. BRIEF DESCRIPTION OF THE DRAWINGS [0019] [0019]FIG. 1 is an exploded view of a sliding block guide in accordance with the invention, [0020] [0020]FIG. 2 is a side view of the sliding block of FIG. 1 and the support which bears the sliding block, [0021] [0021]FIG. 3 shows, on a larger scale, a detailed view of the broken line encircled part of FIG. 2, [0022] [0022]FIG. 4 is a sectional view taken along line A-A of FIG. 3, [0023] [0023]FIG. 5 is a sectional view taken along line B-B of FIG. 3, [0024] [0024]FIG. 6 is a perspective view of the sliding block on a still larger scale, [0025] [0025]FIG. 7 is an enlarged side view of the sliding block guide as show in FIG. 1, [0026] [0026]FIG. 8 shows a partial view of an openable motor vehicle roof equipped with the sliding block guide as shown in FIGS. 1 to 7 with the cover in the closed position, and [0027] [0027]FIG. 9 a partial view similar to that shown in FIG. 8 but with the cover raised. DETAILED DESCRIPTION OF THE INVENTION [0028] [0028]FIGS. 1, 8 and 9 show an embodiment of a sliding block guide 10 in an application for the front lifting and sliding mechanism of the motor vehicle roof known from German Patent DE 100 33 887 C1 and corresponding U.S. Pat. No. 6,568,750. However, it goes without saying that the sliding block guide of the present invention can also be advantageously used for any other mechanism for actuating an openable motor vehicle roof or for a mechanism for actuating a motor vehicle hatch. [0029] The sliding block guide 10 includes a multi-part, essentially rectanguloidal sliding block 11 and a guideway 12 . The sliding block 11 is made essentially mirror symmetrical with respect both to the lengthwise axis and also the transverse axis, and it has a preferably metallic support pin 13 . The support pin 13 is attached, for example, riveted, to a support 14 which is likewise metallic in this embodiment. On the support pin 13 , a carrier part 15 is supported to be able to turn around the axis 16 of the support pin 13 . The carrier part 15 can be made of high strength plastic and can be produced, for example, directly by injection around the support pin 13 . This has the advantage that the injection molded plastic carrier part can turn without play on the support pin 13 , and thus, is free of rattling without further effort. However, the plastic carrier part can also be injection molded separately, and then, can be clipped onto the support pin 13 . In particular, if the sliding block guide 10 is intended for very high stresses, the carrier part 15 can also be made of metal and can be slipped onto the carrier pin 13 . The carrier part 15 has a hub 17 which surrounds the support pin 13 and has two wings 18 which project essentially radially outward from the sides of the hub 17 which are diametrically opposite one another. [0030] A rubber-elastic sliding block body 20 , which is can be made of rubber, is slipped onto the carrier part 15 . The sliding block body 20 has less strength and stiffness than the carrier part 15 and thus it provides for tolerance equalization and damping. The overall essentially cap-shaped sliding block body 20 has a peripheral wall 21 and an end wall 22 which adjoins one end of the peripheral wall 21 . The inside of the end wall 22 adjoins the side of the wing 18 which is turned away from the support 14 . The peripheral wall 21 is slotted in the lengthwise direction of the sliding block at 23 and in the transverse direction of the sliding block at 24 . [0031] Finally, a sliding cap 26 with a peripheral wall 27 and an end wall 28 which adjoins one side of the peripheral wall 27 is slipped onto the sliding block body 20 . In the area of the narrow sides of the sliding block 11 , the inner side of the peripheral wall 27 of the sliding cap 26 is in contact with the narrow sides of the carrier part 15 , while the inside of the peripheral wall 27 in the area of the lengthwise sides of the sliding block is at a distance from the lengthwise sides of the carrier part 15 . The rubber-elastic sliding block body 20 essentially fills the entire space between the carrier part 15 and the sliding cap 26 . The wings 18 can have an essentially constant thickness over their entire length according to either embodiment, and can taper in a radially outward direction. Accordingly, the peripheral wall 21 of the sliding block body 20 , in the area of the wings 18 , has an essentially constant thickness (FIGS. 7 to 9 ) or this thickness increases in the direction toward the wing ends which lie away from the hub 17 (FIGS. 1 to 6 ). In both cases, the explained arrangement provides for the sliding cap 26 to be able to move to a limited degree using the elastic properties of the sliding block body 20 with reference to the carrier part 15 both in the transverse direction of the sliding block 11 and also in the direction of rotation around the axis 16 of the carrier pin 13 . Moreover, the sliding block 11 can be compressed to a limited degree as a whole in the transverse direction, if the sliding cap 26 has limited elasticity. Conversely, the sliding cap 26 and the carrier part 15 engage one another in the lengthwise direction of the sliding block 11 essentially without play. [0032] The inside of the end wall 28 adjoins the outside of the end wall 22 of the sliding block body 20 . On the side of the peripheral wall 27 , facing the support 14 in the area of the narrow sides of the sliding block 11 , there are catch projections 29 . The catch projections 29 lie against a shoulder 30 which is made on the side of the carrier part 15 facing the support 14 . In this way, the-carrier part 15 , the sliding block body 20 and the sliding cap 26 are held securely together. The end wall 28 of the sliding cap 26 has a lengthwise slot 33 . [0033] The sliding cap 26 is preferably made of a plastic with good sliding properties and favorable noise behavior, for example, from polyethylene (PE) or polytetrafluorethylene (PTFE). High density polyethylene (HDPE), such as the material marketed under the trademark RIGIDEX®, is especially well suited for this purpose. The two lengthwise outer sides of the peripheral wall 27 of the sliding cap 26 form two opposite sliding surfaces 34 , 35 . If desired, the outside of the end wall 28 of the sliding cap 26 can be used as another sliding surface. Embossed stripper ribs 36 , which run obliquely to the direction of displacement, are formed on the sliding surfaces 34 , 35 . The stripper ribs 36 provide, on the one hand, for linear contact of the sliding surfaces 34 , 35 of the sliding block 11 with the sliding surfaces 41 , 42 of the guideway 12 , and on the other hand, they form a stripping means for dirt particles. The use of such stripping ribs is known and described in detail in German Patent DE 43 36 222 C1, so that the stripping ribs 36 and their function do not require further explanation. [0034] The guideway 12 has a guide channel 40 into which the sliding block 11 dips (FIGS. 7 to 9 ). Here, the sliding surfaces 34 , 35 of the sliding block 11 are slide-engaged with the sliding surfaces 41 , 42 of the guideway 12 (FIG. 7). [0035] In the embodiment shown in FIGS. 1, 8 and 9 the sliding block guide 10 is part of the front lifting and displacement mechanism for the cover 45 of an openable motor vehicle roof 46 . Here, the cover 45 can be raised by means of a corresponding mechanism and can be pushed over the roof surface, as is described in DE 100 33 887 C1 and corresponding U.S. Pat. No. 6,568,750. The support 14 which is connected to the support pin 13 of the sliding block 11 is attached to the bottom of the cover 45 . The guideway 12 which is formed, for example, from at least one guide rail and/or guide slot is angled forward and down at its front area (which is on the left in FIGS. 8 & 9) so that there is a curved guideway area 49 between the front parallel guideway area 47 which runs obliquely essentially in a straight line and a parallel guideway area 48 which runs essentially horizontally in a straight line and which is located rearward in the lengthwise direction of the motor vehicle. The path of force F indicated in FIG. 7 proceeds from the cover 45 via the support 14 and the support pin 13 to the relatively strong carrier part 15 . The carrier part 15 and the sliding block body 20 which surrounds it reduce the surface pressure between the sliding cap 26 and the sliding partner, i.e., the guide rail or guide slot which forms the guideway 12 . [0036] For passage of the sliding block 11 from one to another of the guideway areas 47 , 48 , 49 without problems even in long term operation, what is important is good curve handling capacity of the sliding block 11 in the guideway 12 . The feature that the guideway 12 is widened in curved areas, such as the guideway area 49 , also contributes to this curve handling capacity here, in addition to the above explained structure of the sliding block 11 . This means that the width W′ (FIG. 8) of the curved guideway area 49 is made larger than the width W of the parallel guideway areas 47 and 48 (FIG. 7). The difference of the widths W′ and W is preferably chosen such that the sliding block 11 is only pushed and turned, but not deformed, as it traverses the sequence of guideway areas 47 , 48 , 49 , if the sliding block 11 and the guideway 12 have their theoretical dimensions. In the curve areas, then “triple-line support” of the sliding surfaces 34 , 35 of the sliding block 11 on the sliding surfaces 41 , 42 of the guideway 12 occurs. The deformation capacity of the sliding block 11 can be fully used for tolerance compensation which may become necessary. [0037] The described sliding block guide enables high cover weights to be supported. The sliding block wears little over the service life of the system and it provides reliably for the absence of rattling of the system.

A sliding block guide for openable motor vehicle roofs or vehicle hatches, with a guideway which has a guide channel ( 40 ), and a sliding block ( 11 ) which is movably guided in the guide channel along the guideway, the guideway has at least one essentially linear guideway area ( 47, 48 ) and at least one curved guideway area ( 49 ). To improve the curve handling capacity of the sliding block, the guide channel ( 40 ) is made wider in the area of the curved areas ( 49 ) of the guideway ( 12 ) than in the area of the essentially linear guideway areas ( 47, 48 ).

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a device and method for determining in situ stresses and/or strength characteristics of a subterranean formation. More particularly, the invention relates to a device for insertion in a borehole extending into a formation, which device when pressurized exerts force radially against the borehole wall in all directions except along one plane dividing the device longitudinally. There are many situations, such as during mining of coal or other mineral from a subterranean formation, where it is desirable to know the existing in situ stresses and/or the strength characteristics of a particular formation. Such knowledge is useful in planning the developement of the formation, and particularly as to the safety of the operation. 2. Description of the Prior Art There are many procedures of varying degrees of usefulness which have been previously utilized in attempts to analyze the stresses and strength characteristics of subterranean formations. One method of determining the strength of a formation has been to seal a portion of a borehole with packers and then pressurize the sealed section. The formation fracture pressure can be determined in this manner, but this only gives information regarding the weakest direction. It is desirable to have information regarding stresses and strength in a plurality of directions and at a plurality of locations in order to analyze a formation by non-destructive methods. Such information is useful in techniques such as finite element analysis of force distribution within a formation. The present invention makes possible a non-destructive "microseismic" method of formation analysis because of its capability for providing information in a plurality of directions which reflects the forces acting on the formation at a given location. SUMMARY OF THE INVENTION According to the present invention, a device is provided which is easily inserted into a borehole extending into a subterranean formation, which device when pressurized exerts uniform radial forces agains the borehole wall in all direction except along a particular plane extending longitudinally through the device. As a result, a parting force is exerted on the formation through that particular plane which is higher than the parting force exerted on any other plane through the axis of the device. The formation typically develops stress microcracks well before failure pressure is exerted on it, and by using a sound pickup with device which detects microcrack occurrence the strength characteristics of a formation can be determined for a given plane through the formation. The formation strength through several planes at a particular location in the formation can be determined by this invention since it is not necessary to fracture the formation to obtain a measurement through a particular plane. Such information is useful for establishing a safe mining program. The device according to the invention includes a pair of inflatable semi-cylindrical members mounted on a shaft having a fluid passage for pressurizing the inflatable members. The device is inserted while uninflated and then when in position it is inflated by fluid pressure such that it contracts the borehole wall and exerts pressure on the wall. Because of the unique structure of the device, no pressure is exerted along one particular plane, and as a result the formation strength through that plane can be determined. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view showing a preferred form of the device. FIG. 2 is a cross-sectional view taken along the line 2--2 of FIG. 1 showing the interior of the upper portion of the device in the pressurized condition. FIG. 3 is a view similar to FIG. 2 but showing the device in the unpressurized condition. FIG. 4 is a top plan view, partly in cross-section, taken along the line 4--4 of FIG. 2 with the device in the pressurized condition. FIG. 5 is a cross-sectional view of the device of FIG. 1, taken along the line 5--5 of FIG. 2 with the device in the pressurized condition. FIG. 6 is a top plan view, partly in cross-section, taken along the line 6--6 of FIG. 3 with the device in the unpressurized condition. FIG. 7 is a view similar to FIG. 5 but with the device in the unpressurized condition. FIG. 8 is a perspective view of a segment forming a part of the device. DESCRIPTION OF THE PREFERRED EMBODIMENTS The most preferred embodiment of the invention will now be described by reference to the accompanying drawings illustrating same. The overall device 10 is illustrated generally in FIG. 1, and as best seen in FIGS. 2 and 3 includes a central shaft member 11 having a fluid passage 12 extending from the top end of the device to an intermediate portion of the shaft. Fluid passage 12 intersects a transverse fluid passage through shaft 11 constituting a pair of outlets 13. A pair of elastomeric semi-cylindrical members 14 are bonded to shaft 11 and plate 25 (FIGS. 5 and 7) and positioned so as to form a generally cylindrical structure. Each semi-cylindrical member 14 includes an opening in register with an outlet 13 such that fluid transmitted down fluid passage 12 flows into semi-cylindrical members 14. An insert 15 extends from the interior of each member 14 into each outlet 13 to help position the opening in member 14 over outlet 13. The member 14 may be formed of any natural synthetic tough elastomeric material. Butyl rubber is a particularly good material for these members. The top end of device 10 includes a fixed support plate 16 attached to shaft 11 (FIG. 2). A floating support plate 17 (FIGS. 2 and 3) movable axially along shaft 11 is positioned just above the upper ends of members 14. Floating support plate 17 has an upper angled surface 18 (FIG. 3), the purpose of which will be described later. Located between fixed support plate 16 and floating support plate 17 is a segmented radially expandable disc unit constructed of a plurability of segments 20 as shown in FIGS. 1, 4 and 6. Each segment 20 forms a part of a circle in plan view, and the inner edge of each segment 20 is shaped to fit about shaft 11 when the device is in the unpressurized condition as shown in FIG. 6. Near the inner end of each segment 20 is a spring-retaining groove 21, and a spring 22 or elastic ring in the groove 21 of a series of segments 20 operates to bias the segments against shaft 11. Each segment 20 has an angled surface 23 (FIG. 3) which matches angled surface 18 on floating support plate 17. It will be apparent that upon movement of floating support plate 17 toward the expandable disc formed of segments 20 that the angled surface 18 of plate 17 will act on angled surfaces 23 on segments 20 and move the segments 20 radially outward from shaft 11. As is clear from FIG. 2, the outward movement of segments 20 is limited. Upon movement of floating plate 17 away from the disc unit, spring 22 acts to return segments 20 to the original position shown in FIGS. 3 and 6. A microphone 24 including an electrical lead 29 is shown mounted on upper support plate 16 for purposes to be described later. The lower end of device 10 includes substantially indentical parts as described above for the upper end, except that no microphone is associated therewith. Referring now to FIGS. 5 and 7, shaft 11 includes flat plate members 25 extending outwardly therefrom and constituting separating means for keeping the flat surfaces of inflatable members 14 out of contact with each other. The outer edge of each plate member 25 has a slot 26 formed therein, and a strip 27 is positioned in each slot 26 and biased outwardly by springs 28 and retained by a shoulder formed near the outer limit of slot 26. The operation of the device 10 will now be described for a typical project of determining the strength characteristics of a subterranean formation. First, a borehole having a diameter slightly larger than that of fixed support plate 16 of the device 10 is drilled into a subterranean formation. The device 10 is then lowered into the borehole by pipe joints (not shown) connected to shaft 11, care being taken to maintain a known orientation of device 10 within the borehole. When the device 10 is at the desired depth, fluid is introduced through passage 12 into members 14. Members 14 expand slightly in response to the fluid pressure, and contact the wall of the borehole. Continued injection to fluid into members 14 forces the ends of members 14 outwardly against floating support plates 17, which in turn move outwardly against segments 20 of the disc units, causing segments 20 to move slightly outwardly by the camming action of surface 18 against surface 23. When segments 20 have moved to the full outward position, their outer surfaces are against or very near the wall of the borehole as shown in FIGS. 2 and 4, such that upon increasing the pressure in members 14 the ends thereof cannot bulge out beyond fixed support plates 16. Thus, it will be seen that device 10 can be built with a diameter smaller than the diameter of the borehole in which it is to be used, enabling easy insertion of the device in the borehole. At the same time, expandable disc units formed of segments 20 between fixed support plates 16 and floating plates 17 can extend outwardly to fill the gap between the fixed support plates and the borehole wall upon inflation of members 14, thereby preventing bulging out and bursting of the members 14 when they are subjected to high pressures. When the expandable disc units are in the enlarged or outermost position, fluid pressure in members 14 is increased until microcracks begin to form in the formation along the plane between the inflatable members 14. This might require a pressure in members 14 of several hundred kilograms per square centimeter. As the microcracks begin to form, typically at about half the pressure required to fracture the formation, the microphone 24 detects the sound generated and transmits it to the operator. The pressure in members 14 is then released, and springs 22 retract segments 20 away from the borehole to the position shown in FIGS. 3 and 6. The device is then rotated through a desired angle and/or moved longitudinally in the borehole, and the process is repeated until sufficient measurements have been made to enable an analysis of the strength characteristics of the formation. To retrieve the device 10 from the borehole, the pressure in members 14 is released, allowing segments 20 to retract, and the device is then pulled out. Strips 27 do not significantly retard removal, as they are pushed back into slots 26 by the borehole wall. The number of segments 20 required for each disc unit is determined by the amount of radial movement expected, the strength of the elastomeric member, and the symmetry of the borehole. More than six are required to provide any improvement, as with six segments the maximum dimension of the gap between segments upon expansion is the same as the dimension between the unexpanded and expanded radii. Preferably from 24 to 48 segments are used, with 36 being a particularly preferred number of segments for each disc unit. In accordance with an alternative simplified version of the invention (not shown), the floating support plates 17 and segments 20 can be eliminated, and the inflatable members 14 can bear directly on fixed support plates 16. This version generally requires a closer fit between the device and the borehole to prevent bulging of the pressurized inflatable members past the fixed support plates. Likewise, this version can be used without the slot and strip in the separating members. The foregoing detailed description of the construction and operation of the most preferred embodiment of the device is intended to be illustrative rather than limiting, and it will be apparent to those skilled in the art that numerous modifications and variations could be made without departing from the true scope of the invention, which is defined by the appended claims.

A device and method for determining strength properties of a subterranean formation. The device is insertable into a borehole formed in the formation, and includes a pair of inflatable semi-cylindrical members mounted on a shaft. The inflatable members when pressurized exert radial force in all directions except along the plane between the members, with the result that a higher parting force is exerted on the formation perpendicular to the plane between the members than across any other plane through the axis of the device.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION This invention relates generally to the transmission of information from near the bottom of a wellbore to the surface of the earth via production of positive and negative pressure pulses in drilling fluid being circulated downwardly in a drill pipe string. More particularly, it concerns improvements in apparatus and methods associated with production of such pulses. In U.S. Pat. No. 4,550,392 to Mumby, incorporated herein by reference, positive pulses are produced, while well fluid flows downwardly through an annular space, the effective cross sectional area of which remains unchanged, i.e., is fixed, that space surrounding a valving apparatus in another flow path. The valving apparatus can close off the one flow path forcing all flow to circulate through the other, unchanging, cross sectional area. The increased volume through the constant, unchanging area flow path results in increased pressure drop across the apparatus. By closing, then opening, the valving apparatus, a pulse is created. As a result of this unchanging flow cross sectional area, there are disadvantages that limit the ability to control the characteristics of the resultant pulse. One prominent disadvantage is inability to control physical characteristics of the resultant pressure pulse. For example changes in the flow rate or physical properties of the fluid change the working pressure across the valving mechanism and change the pulse amplitude. There is need to control these physical characteristics because it is found that pulse amplitudes can become too small, for detection of the pulse at the surface. Conversely, the pulse can become too large causing equipment damage and unnecessary erosion and energy drain. Variations in generated pulse amplitude can override otherwise predictable attenuation of pulse pressure amplitude with path length, drill fluid density, drill fluid viscosity, and drill fluid shear strength. SUMMARY OF THE INVENTION It is a major object of the invention to provide a solution to the above-mentioned problem. Basically, the method of the invention includes the steps: a) producing the positive pressure pulses in a downwardly flowing drilling fluid stream at a sub-surface location in the string, by restricting one or more flow paths, so these pressure pulses are transmitted upwardly in the fluid, b) varying the flow area of the alternative, parallel flow path, thereby introducing or removing a restriction, thus controlling the amplitude of the pulses. As described below, a separate valve means is typically provided in a parallel flow path, which may be annular or collinear, to the interruptible path. The described valve means controllably alters the cross sectional flow area of this parallel flow path. The valve means may be yieldable, as via spring means, to increasingly pass the downwardly flowing well fluid in response to increasing downward pressure exerted by the flowing drilling fluid. Also, a plurality of valves may be provided with either the same or differing pass characteristics as the downward pressure exerted by the flowing drilling fluid varies. Also, a combination of valves and flow ports may be provided. Another object is to provide a means in the form of multiple valves that are spring urged to yieldably open, increasing, in response to increased pressure of the flow, thereby to vary the flow area to achieve the desired benefits, as described. Another object of this invention comprises providing an apparatus that includes: a) structure including multiple hydraulically parallel flow channels, one of which includes valving means which when closed, increases pressure drop across the alternate flow channels, the increase which is removed when this valving means is opened, resulting in an ability to create a pressure pulse within the fluid stream flowing downwardly through the drill pipe, the pressure pulse then propagating upwardly to a point within the drill string hydraulically upstream of the pulse-generating apparatus, b) and other means for varying the cross sectional area of the hydraulically parallel flow channels through which the fluid flows downwardly through an increase pressure drop, when the valving means is closed, for controlling the amplitude of the upwardly transmitted pulses. A wireline may be attached to the structure, for displacing it lengthwise in the string relative to the other means referred to. That other means may include a body means having a shoulder, commonly known in the industry as landing ring or muleshoe landing, to engage the structure for positioning in the string. That means, known as a landing ring or muleshoe landing, may include the other means, for varying the cross section area of the flow channel. Another object includes provision of said structure to comprise: i) a tubular body defining a passage to pass well fluid downwardly past the zone, ii) and valving for controllably interrupting the passing of well fluid downwardly past the zone. As will be seen, such valving typically includes a valve seat, a valve member movable toward and away from the seat, and a piston movable in a bore in the body, and in response to controllable application of well fluid pressure to the piston to control reciprocation of the member in the bore. A further object includes provision of a tube extending endwise in the body and having well fluid inlet porting above the seat and well fluid exit porting below the seat to alternatively pass well fluid pressure to the piston, and to the exterior of the body. A first annular seal typically seals off between the piston and bore, and a second annular seal seals off between the piston and the tube, the tube extending downwardly within the piston. This structure provides for simplicity of interfitting of parts and guidance of piston reciprocation. Additional objects include provision of a flow diverter carried by the body at a location above the upper end of the tube to divert well fluid to flow toward the zone, and also toward the passage; and provision of a filter carried by the body to filter fluid flowing toward the passage. These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which: DRAWING DESCRIPTION FIG. 1 is a schematic view showing one form of the invention; FIG. 2 is a view like FIG. 1 but showing more detail; FIG. 3 is an enlarged top plan view schematic showing a proposed form of the means to vary the flow cross sectional area, sidewardly of flow channel containing the valving means; FIG. 4 is a sectional schematic taken on lines 4--4 of FIG. 3; FIG. 5 is a further enlarged schematic view taken on lines 5--5 of FIG. 4; FIG. 6 is an elevation taken in section showing a pulse-producing means, in open position; and FIG. 7 is a view like FIG. 6 showing the pulse-producing means in closed position. DETAILED DESCRIPTION In FIG. 1, apparatus 10 includes a structure, generally indicated at 16 that contains valving apparatus, i.e., the first means to produce pulses, indicated by dashed lines 19 in the well fluid, such pulses translated along a drill pipe or drill collar string 11. Well drilling fluid, or drilling mud, flows downwardly in the string, as indicated by arrows 12. In this path, it is constrained by the internal diameter of the string bore 18. Although well casing is indicated at 13, annulus indicated at 14 may be located between the drill string 11 and an earth borehole 66 inside the diameter. The return fluid contains cuttings created by the drill bit (not shown) and travels up this annulus 14, as indicated by arrows 15. Within the structure 16, three means are indicated. The first means is indicated at A and is the means to produce pulses and may include valving elements, as disclosed in U.S. Pat. No. 4,550,392 to Mumby, or in U.S. Pat. No. 4,120,097 to Jeter, both patents incorporated herein by reference. Other types of pulse-producing devices are usable. An actuator means is substantially shown at B for translating electrical energy from a source (not shown) to drive the pulse-creating means A; and circuitry at C is responsive to sensors shown at C', so as to modulate production of pulses in accordance with information or data transmitted upwardly to a surface detector, indicated schematically at D. The structure 16, which may be tubular, is capable of being run in the string 11 on a wireline 17, while fluid flows in the string. Referring to FIG. 2, the structure 16 is shown translated in the string into an annular body 24, which contains flow passages 128 and 128'. Body 24 also defines a receiving passage 25, or bore, which is constructed for receipt of 16. The receiving passage 25 and flow passages 128 and 128' may be located within a landing ring or muleshoe. When the structure 16 comes to rest, it is in a preferred orientation and position by virtue of a correctly located and constructed upset on the outer diameter of the structure 16 as at 16b, FIG. 2, and rests or seats on the upper face of the annular body 24. The annular body 24 is itself suitably suspended, as indicated by a shoulder 26, or other acceptable means within the string bore. In FIGS. 1 and 2, the presence of the annular body 24 is seen to divide the passage within the drill string into two regions 23 and 44 relative to flow. The regions are connected by a passage 22 through the structure 16. These regions are also connected via flow passages 128 and 128' in 24. By virtue of the restriction to flow offered by the passages 128 and 128' in body 24, the upstream region 23 and downstream region 44 will possess different pressures P 1 and P 2 , respectively. The passage through the structure 16 enters an inlet duct 21 from the upstream region 23, and passes through a valving means 20, and exits through a passage 22 into the downstream region 44. Referring to FIG. 4, the flow passage 128 may contain a short receiving port 128a communicating with a threaded port 128b. FIGS. 3 and 4 show ports 128 spaced about bore 25, and with through ports 128' of fixed area located between pairs of ports 128. The threaded port 128b is adapted to support the variable area means, here shown as including sleeve 132. A threaded upper coupling extent 132a of 132 is received in threaded bore 131. This variable area flow means, which may include valve means 136, responds to changes in fluid pressure above and below 24, and/or changes in drilling fluid flow rates, or viscosity, or composition, to vary the flow area between the upstream region 23 and the downstream region 44, to produce the desired benefits. The valving means 136, as for example a spring-urged valve employing a dashpot, variably controls the flow area, as will be explained below. Referring now to FIG. 3, it shows the top of the annular body 24 suspended in the drill string with the outer surface of the structure 16 received in the receiving passage or bore 25. The two distinct types of flow passages 128 and 128' are illustrated. As referred to, passages 128 are threaded to support the variable area means, including sleeves 132 and valving means 136. Passages 128' are shown as constant area passages. FIG. 4 further illustrates the differences in these two types of flow passages, and shows hanging support the body 24 at string shoulder 26, so that the bore 25 of the annular body 24 passes structure 16. As illustrated in FIG. 5, lower end of threaded coupling 132a is inserted in upper extent of sleeve 132. Upper end of coupling 132a is received in the matching internal thread 131 in the annular body 24 in lower end extent of passage 128, until the shoulder 130 on 132 engages the lower surface of the annular body 24. FIG. 5 shows details of the variable area valving means 136. Pressure P 1 of liquid at upper zone 23 is applied to the upper tapered surface 137 of 136 when surface 137 is seated on the tapered seat 136a. When the valve element is seated, the downstream pressure P 2 at zone 44 is applied through side ports 143 is applied to other surfaces of the valve means 136, and along the non-sealing bore wall 138 of the sleeve or housing 132. As flow variation at zones 23 and 44 causes the pressure P 1 to increase relative to P 2 , there is a net opening force exerted downwardly on the valve element. That opening force is yieldably resisted by the spring force of spring 139 applied upwardly on the opposing face 141 of the valve element. The rate of alteration of the flow area of the valve with changes in the difference between P 1 and P 2 is restricted by reaction forces transmitted along shaft 152 of a dashpot formed in liquid-containing cavity 161 in the housing 132. Shaft 152 is connected at its lower end to the dashpot piston 151, and at its upper end to the valve element 136. Response to the dashpot is controlled by sealing the shaft 152 with seal 156, and the piston 151 with seal 155, leaving only controlled leaks at ports 160 and 150. Port 150 communicates pressure P 2 to the cavity antechamber 159. Pressure offset is accomplished by adjusting the spring preload and spring rate on spring 139. Time response, which allows the valve to yieldably respond only to pressure differences expressed over time long with respect to local transient, is accomplished by adjusting the controlled leaks at 160 and 150. Orifices 150 and 160 restrict outflow of fluid from chambers 161 and 159 as the piston moves up and down, creating a dashpot effect, in conjunction with spring 139. A selected number of such valves 136 is installed in body 24, to achieve desired modulation of the signaling pulses created by opening and closing of the valve means 16. As an alterative, a dual acting, non cavitating apparatus may be formed by modifying the shaft 152 and adding a seal. For example, by extending shaft 152, after attachment to piston 151, through a seal (not shown) in position 150 and moving the lower controlled leak adjacent to piston 151. This results in two sealed chambers 161 and 159 connected via a controlled leak. Reference is now made to FIGS. 6 and 7 showing a representative pulse-producing means indicated generally at 200, lowered in the drill string 13, and carried by body 24, as discussed above. As shown, a tubular valving body 201 is vertically elongated and has a shoulder 201a seated on the body 24. Valving body 201 defines a passage to pass well fluid or liquid downwardly, as via passage sections 202, 203, and 204, as indicated by flow path arrows in FIG. 6. Under such condition, the valving passage is open to downward flow of well (hydraulic) liquid. The valving is operable to controllably interrupt such downward passage of well fluid through passages 202, 203, and 204, and past body 24 discussed above. Body 24 varies the flow through its passage 128 and the flow controller 132 of variable cross section opening. The valving means includes a valve seat 206, which is upwardly tapered, and a valve member 207 movable toward and away from the seat. When closed, as in FIG. 7, the tapered surface 207a of member 207 closes against seat 206, blocking downward flow, and a pulse is produced in the well fluid above the body 24, i.e., in region 23. That pulse travels upwardly in the string, and serves as a signaling pulse, as referred to above. Valve member 207 is annular, and its up and down movement is guided by a tubular stem 208. An annular seal 209 seals off between the bore of member 207 and the outer surface 208a of the stem. An annular seal 230 carried just below the seat 206 sealingly engages the tapered surface 207a in valve closed condition. A piston 211, connected to valve member 207, is movable in body bore 212, in response to controllable application of well fluid pressure to the piston surface 211a, to control reciprocation of the valve member in the bore. Note that only one O-ring 213 seals off between the body bore 212 and the piston skirt, for simplicity. Also, this allows concentricity of sliding and alignment of the valve 207 on the stem, to prevent binding. Compression spring 214 exerts upward force on the piston, to assist in closing of the valve. A pilot control valve 215 is located at the lower end of the stem 208 to control piston reciprocation when the pilot valve is open, as in FIG. 6, pressurized well fluid flows downwardly into the stem via ports 217, and exhausts via the lower end of the tubular stem and via side passages 218 into the string at 219. When the pilot valve is closed, the well fluid pressure in the stem flows via exit side (lower) ports 220, into the chamber 221, to exert upward pressure on the piston, to close valve member 207 against the seat 206, as seen in FIG. 7. A driver to open and close the pilot valve is shown at 225. A flow diverter is shown at 226 at the upper end of the stem 208, to divert well fluid flow toward region 23 above body 24. Diverter 226 is upwardly tapered at 226a. Well fluid flow also passes through an annular filter 227 between the diverter and the top of the valving body 201, to block travel and access of said other particle to the valve elements 206 and 207.

In fluid pulsing apparatus operable in a drill pipe in a well in which well drilling fluid flows, wherein pressure pulses are created by restricting one or more of several hydraulically parallel paths, constant working pressure regulating valves with a long time constant relative to the transient pulses are constructed in the hydraulically parallel paths. The valves operate to produce a more consistent pulse character allowing production of pulses at low flow rates of drilling fluid that are of sufficient amplitude to be more easily detected on the Earth's surface and restriction of amplitude of pressure pulses at high flow rates of drilling fluid to limit equipment damage and loss of hydraulic energy. The valves function by varying the flowing cross sectional area of the hydraulically parallel paths.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] Embodiments of the present invention generally relate to an electrical submersible pump assembly adapted to efficiently reduce a gas content of a pumped fluid. Particularly, embodiments of the present invention relate to an electrical submersible pump assembly having a device to direct gas flow leaving the assembly. [0003] 2. Description of the Related Art [0004] Many hydrocarbon wells are unable to produce at commercially viable levels without assistance in lifting formation fluids to the earth's surface. In some instances, high fluid viscosity inhibits fluid flow to the surface. More commonly, formation pressure is inadequate to drive fluids upward in the wellbore. In the case of deeper wells, extraordinary hydrostatic head acts downwardly against the formation, thereby inhibiting the unassisted flow of production fluid to the surface. [0005] In most cases, an underground pump is used to urge fluids to the surface. Typically, the pump is installed in the lower portion of the wellbore. Electrical submersible pumps are often installed in the wellbore to drive wellbore fluids to the surface. [0006] In a well that has a high volume of gas, a gas separator may be included in the ESP system to separate the gas from the liquid. The gas is separated in a mechanical or static separator and is vented to the well bore where it is vented from the well annulus. The separated liquid enters the centrifugal pump where it is pumped to the surface via the production tubing. [0007] In a well that produces methane gas, the electrical submersible pump is generally used to pump the water out of the wellbore to maintain the flow of methane gas. Typically, the water is pumped up a delivery pipe, while the methane gas flows up the annulus between the delivery pipe and the wellbore. However, it is inevitable that some of the methane gas entrained in the water will be pumped by the pump. Wells that are particularly “gassy” may experience a significant amount of the methane gas being pumped up the delivery pipe. [0008] For coal bed methane wells, it is generally desirable that no methane remain in the water. Methane that remains in the water must be separated at the surface which is a costly process. Therefore, a gas separator may be used to separate the gas from liquid to reduce the amount of methane gas in the pumped water. [0009] FIG. 1 shows a prior art downhole electric submersible pump (ESP) assembly 10 positioned in a wellbore 5 . The ESP assembly 10 includes a motor 20 , a motor seal 25 , a gas separator 30 , and a pump 40 . The gas separator 30 is positioned between the pump 40 and the motor seal 25 . The motor 20 is adapted to drive the gas separator 30 and the pump 40 . A central shaft extends from the motor 20 and through the motor seal 25 for engaging a central shaft of the separator 30 and a central shaft of the pump 40 . Fluid enters the ESP assembly 10 through the intake port 32 in the lower end of the gas separator 30 . The fluid is separated by an internal rotating member with blades attached to the shaft of the gas separator 30 . The gas separator 30 may also have an inducer pump or auger at its lower end to aid in lifting the fluid to the blades. Centrifugal force created by the rotating separator member causes denser fluid (i.e. fluid having more liquid content) to move toward the outer wall of the gas separator 30 . The fluid mixture then travels to the upper end of gas separator 30 toward a flow divider in the gas separator. The flow divider is adapted to allow the denser fluid to flow toward the pump, while diverting the less dense fluid to the exit ports 38 of the gas separator 30 . Gas leaving the gas separator 30 travels up the annulus 7 . [0010] One problem that arises is that the gas leaving the gas separator may commingle with the fluid flowing toward the intake port. In this respect, the gas content of the pumped fluid may be inadvertently increased by the gas leaving the separator. The increase in gas entering the gas separator when this occurs reduces the efficiency of the gas separator which may result in incomplete separation of the gas from the liquid. This has negative effects on pump performance and in a coal bed methane well will result in methane in the water being pumped from the well. [0011] There is a need, therefore, for an apparatus and method for efficiently reducing a gas content of a pumped fluid. There is also a need for apparatus and method for maintaining a separated gas from a fluid to be pumped. SUMMARY OF THE INVENTION [0012] Embodiments of the present invention provide methods and apparatus for preventing a separated gas leaving a pump assembly from mixing with a fluid in the wellbore. [0013] In one embodiment, a pump assembly for pumping a wellbore fluid in a wellbore comprises a pump; a gas separator; a motor for driving the pump; and a shroud disposed around the gas separator for guiding a gas stream leaving the gas separator, wherein the gas stream is prevented from mixing with fluids in the wellbore. In one embodiment, the shroud guides the gas stream to a location above a liquid level in the well bore. [0014] In another embodiment, a method of pumping wellbore fluid in a wellbore includes receiving the wellbore fluid in a separator; separating a gas stream from the wellbore fluid; exhausting the gas stream from the separator; and guiding a flow of the exhausted gas stream up the wellbore while substantially preventing the gas stream from mixing with fluids in the wellbore. The method further includes venting the gas stream above a fluid level in the wellbore and pumping the wellbore fluid remaining in the separator. In one embodiment, the method also includes disposing a shroud around the separator to guide the flow of the exhausted gas stream. [0015] In another embodiment gas is vented above a zone where all the fluid is entering the well annulus. This can be a perforated zone or entry of multilateral legs in the well. [0016] In yet another embodiment, a pump assembly for pumping a wellbore fluid in a wellbore includes a pump, a gas separator having a vent port, a motor for driving the pump, and a tubular sleeve in fluid communication with the vent port, wherein a gas stream in the tubular sleeve is prevented from mixing with fluids in the wellbore. [0017] In yet another embodiment, a pump assembly for pumping a wellbore fluid in a wellbore includes a pump, a gas separator having a vent port, a motor for driving the pump, and a flow control device coupled to the vent port, wherein the vent port controls the outflow of a separated gas stream and the inflow of fluids through the vent port. In one embodiment, the flow control device includes an elastomeric tubular sleeve disposed around the vent port. In another embodiment, one end of the tubular sleeve is attached to the gas separator and another end of the tubular sleeve has a clearance between the tubular sleeve and the gas separator. BRIEF DESCRIPTION OF THE DRAWINGS [0018] So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. [0019] FIG. 1 is a schematic view of prior art electric submersible pump. [0020] FIG. 2 is a schematic view of an embodiment of an electric submersible pump assembly. [0021] FIG. 3 is a cross-sectional view of a gas separator highlighting the separation of liquid and gas shown in FIG. 2 . [0022] FIG. 4 is a cross-sectional view of the top of a gas separator that has the gas vented in a conduit. [0023] FIG. 5 is a cross-sectional view of the top of a gas separator that has a flapper valve on the gas vents. [0024] FIG. 6A is a partial view of a gas separator having a tubular sleeve type fluid control device. FIG. 6B is a partial view of another embodiment of a gas separator having a tubular sleeve type fluid control device. [0025] FIGS. 7A-B are partial views of a flap type fluid control device for a gas separator. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0026] Embodiments of the present invention provide methods and apparatus for preventing a separated gas from commingling with fluids in the well bore. [0027] FIG. 2 shows an embodiment of an electric submersible pump assembly 100 adapted to prevent the separated gas from commingling with the wellbore fluid. The ESP assembly 100 includes a motor 120 , a motor seal 125 , a gas separator 130 , and a pump 140 . The motor 120 is adapted to drive the gas separator 130 and the pump 140 . A central shaft extends from the motor 120 and through the motor seal 125 for engaging a central shaft 133 of the separator 130 and a central shaft of the pump 140 . The motor seal 125 may be used to couple the motor 120 to the separator 130 and the pump 140 . In one embodiment, the motor seal 125 is a barrier type seal having an elastomeric diaphragm or bag. Other suitable motors and motor seals known to a person of ordinary skill are also contemplated. [0028] FIG. 3 illustrates an exemplary gas separator suitable for use with the electric submersible pump assembly 100 . In one embodiment, the gas separator 130 includes one or more intake ports 132 at its lower end and one or more exhaust ports 138 at its upper end. The separator 130 includes a rotating member 145 with blades (e.g., a propeller) that is attached to the shaft 133 of the separator 130 and is rotatable therewith. The separator 130 may optionally include an inducer pump or auger 147 at its lower end to aid in lifting the fluid to the blades. The separator 130 may further include a bearing support 151 to provide support to the shaft 133 during rotation. Rotation of the shaft 133 by the motor 120 causes the inducer 147 to rotate, thereby lifting the fluids entering the intake ports 132 . Rotation of the shaft 133 also causes the rotating member 145 to generate a centrifugal force in the gas separator 130 . The centrifugal force causes the denser fluid (i.e. fluid having more liquid content) to move toward the outer wall of the separator 130 and the less dense fluid (i.e., fluid having more gas content) to collect in the central area of the separator 130 . The fluid mixture then travels up the separator 130 and passes through a flow divider 135 positioned at an upper portion of the separator 130 . [0029] In one embodiment, the flow divider 135 includes a lower ring 134 and a conical upper end, as illustrated in FIG. 3 . Orientation of the flow divider 135 is parallel to and coaxial with the central shaft 133 . The lower ring 134 has a diameter that is smaller than the inner diameter of the separator 130 . An inner fluid passage 136 connects the interior of the lower ring 134 to exhaust ports 138 in the sidewall of the separator 130 . As the fluid flows up and toward the flow divider 135 , the more dense fluid located near the outer wall of the separator 130 are outside of the perimeter of the lower ring 134 . Thus, the denser fluid is allowed to flow around the flow divider 135 and up the outer passage 142 toward the conical upper end, which leads to the pump 140 . The less dense fluid (also referred to herein as “separated gas”) located in the inner part of the separator 130 are within the boundary of the lower ring 134 . Thus, the separated gas enters the lower ring 134 and is diverted into the fluid passages 136 and out through the exhaust ports 138 . In this respect, the flow divider 135 may be used to separate the gas from the liquid. It must be noted that other suitable fluid dividers known to a person of ordinary skill in the art may also be used, for example, a rotary gas separator. [0030] Referring back now to FIG. 2 , the ESP assembly 100 is provided with a shroud 150 to guide the flow of the separated gas up the annulus 7 . In one embodiment, the shroud 150 is tubular shaped and is positioned around the separator 130 and the pump 140 , thereby creating an annular area between the separator 130 and the shroud 150 . The length of the shroud 150 is such that the lower end extends below the exhaust ports 138 and the upper end extends above the exhaust ports 138 to a height that is above the liquid level 9 in the wellbore 5 . As shown, the lower end of the shroud 150 remains open to the well bore 5 . The opening may allow venting of the gas below exhaust ports 138 , if the need arises. Alternatively, the lower end of the shroud 150 may be closed to the well bore. The shroud 150 may be coupled to the ESP assembly 110 using a connection member such as a centralizer 137 . The centralizer 137 allows fluid flow in the annular area 139 while serving as a connector for the shroud 150 to the ESP assembly 110 . In another embodiment, the connection member may be one or more spokes or other suitable connection device capable of allowing fluid flow up the annular area. It must be noted that although the shroud is described as extending above the liquid level in the well, the shroud may be extended to any suitable length. For example, the upper end of the shroud may extend above the exhaust ports to a height that is above a zone where all of the fluids enter the well annulus. This zone may be the perforated zone or entry of multilateral legs in the well. [0031] The ESP assembly 110 may optionally include a motor shroud 160 to guide the flow of wellbore fluid into the ESP assembly 110 . In one embodiment, the motor shroud 160 is tubular shaped and is positioned around the motor 120 and the intake port 132 . The inner diameter of the motor shroud 160 is larger than the outer diameter of the motor 120 such that fluid flow may occur therebetween. The upper end of the motor shroud 160 is connected to the separator 130 at a location above the intake port 132 and is closed to fluid communication. The lower end of the motor shroud 160 extends at least partially to the motor 120 , preferably, below the motor 120 . To enter the intake port 132 , wellbore fluid must flow down the exterior of the motor shroud 160 , around the lower end of the motor shroud 160 , and up the interior of the motor shroud 160 toward the intake port 132 . The wellbore fluid circulating the motor shroud 160 advantageously cools the motor 120 , thereby reducing overheating of the motor 120 . [0032] In operation, the ESP assembly 110 may be used to pump water out of a coal bed methane well. The ESP assembly 110 is positioned in the well bore 5 such that the intake port 132 is below the perforations 8 in the wellbore 5 . Wellbore fluid 11 , which may be mixture of water and gas, may enter the annulus 7 through the perforations 8 and flow downward toward the intake port 132 . The fluid 11 may flow past the exterior of the motor shroud 160 , then up the interior of the motor shroud 160 . The wellbore fluid 11 enters the ESP assembly 110 through the intake port 132 of the separator 130 . The motor 120 rotates the rotating members 145 of the separator 130 to apply centrifugal force to the well bore fluid 11 . The centrifugal force causes the denser fluid to move toward the sidewall of the separator 130 as the wellbore fluid 11 travels up the separator 130 . As the wellbore fluid 11 nears the flow divider 135 , the denser, higher water content fluid located near the sidewall is allowed to flow past the inner ring 134 and up the outer passage 142 toward the pump 140 , where it is pumped to a tubing for delivery to the surface. The less dense, higher gas content fluid located in the inner area of the separator 130 enters the lower ring 134 , flows through the fluid passages 136 , and leaves the separator 130 through the exhaust ports 138 . After leaving the separator 130 , the separated gas is guided up the annular area 139 between the shroud 150 and the separator 130 by the inner wall of the shroud 150 . The separated gas is vented out of the shroud 150 at a location that is above the wellbore fluid level 9 . In this respect, the separated gas is substantially prevented from commingling with the wellbore fluid 11 flowing toward the lower end of the ESP assembly 110 . In this manner, water may be efficiently removed from the coal bed methane well. [0033] FIG. 4 shows another embodiment of a ESP assembly. In this embodiment, the ESP assembly is equipped with a flow tube 239 connected to the exhaust port 238 of the separator 130 . The flow tube is adapted to guide the flow of separated gas from the separator and up the annulus 7 . The length of the flow tube 239 is such that the upper end extends to a height above liquid level in the wellbore 5 . [0034] FIG. 5 shows another embodiment of a gas separator equipped with a valve to control the flow of separated gas out of the exhaust port 138 . In one embodiment, the valve is a flapper valve 236 . The flapper valve 236 may be adapted to open at a predetermined force. For example, the flapper valve 236 may be spring biased to close. In this respect, flapper valve will only open if the separated gas in the separator can generated enough force to open the flapper valve 236 . In the closed position, the flapper valve 238 keeps fluids from entering through the exhaust port 138 . Other suitable types of valves include one-way valves, backflow valve, check valve, and ball valve. [0035] FIG. 6A shows another embodiment of a flow control device for the gas separator 330 . The flow control device may be a tubular sleeve 310 and positioned around the exhaust port 338 of the gas separator 330 . One end 311 of the tubular sleeve 310 is attached to the outer surface of the gas separator 330 while the other end 312 is unattached. The free end 312 has an inner diameter that is slightly larger than the outer diameter of the gas separator 330 . The difference in diameters creates an opening 315 for the separated gas to vent. In one embodiment, the tubular sleeve 310 is made of an elastomeric material such as rubber. When a large amount of liquid tries to enter through the opening 315 , the liquid would force the elastomeric tubular sleeve 310 against the gas separator 330 , thereby closing the opening 315 . In another embodiment, the tubular sleeve 310 may be positioned in a recess 325 in the outer surface of the gas separator 330 , as illustrated in FIG. 6B . The tubular sleeve 310 placed in the recess 325 would reduce the potential of liquid flowing into the gas separator 330 . [0036] In another embodiment, the flow control device may be one or more flaps 350 disposed adjacent the exhaust port 338 , as illustrated in FIGS. 7A-B . The flap 350 may be manufactured from an elastomeric material, but should have sufficient rigidity to remain substantially straight. In one embodiment, a metal support 360 may be attached to the flap 350 to provide additional rigidity to the flap 351 . Fasteners such as rivets 365 or adhesive may be used to attach the metal support 360 to the flap 351 . One end 351 of the flap 350 is anchored (or attached) to the gas separator. The anchor may be an elastomeric anchor or any suitable anchor capable of keeping the flap 351 substantially vertical. In operation, the flap 351 is hingedly attached to the gas separator. The flap 351 may be pushed open by the venting gas. Thereafter, the flap 351 swings back to the closed position. [0037] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follows.

In one embodiment, a pump assembly for pumping a wellbore fluid in a wellbore includes a pump, a fluid separator, a motor for driving the pump, and a shroud disposed around the fluid separator for guiding a gas stream leaving the fluid separator, wherein the gas stream is prevented from mixing with fluids in the wellbore.

You are an expert at summarizing long articles. Proceed to summarize the following text: [0001] Node building system for tubular structures. The system is based on the availability of a plurality of nodes ( 7 ) different from one another, formed by pairs of profiles ( 2 ) or ( 2 a ) or ( 2 ′) or ( 2 ″) or ( 2 ″′), linked together to form the corresponding node ( 7 ) and to allow the mounting and connection of tubular arms ( 1 ) that will make up the structure itself and the tubular arms of which may be left aligned longitudinally, form a right angle with one another, form “T” configurations, come together in nodes with four tubular arms ( 1 ), in nodes with five tubular arms ( 1 ), and even more, to allow to form any type of structure for various buildings, both in construction as well as furniture and other. OBJECT OF THE INVENTION [0002] This invention refers to a modular building system for structures and specifically incorporating nodes defined in them, equipped to allow different types of buildings, without discarding its application in furniture and in any other practical purpose where a structure is required from which any type of construction can be created based on tubular profiles. [0003] There are modular constructions of structures, for buildings and other uses, however, in some cases, due to their complexity and in others due to their lack of reliability, what is true is that the systems known until now do not function efficiently, meaning, that they do not allow the erection of buildings with a complete guarantee of safety and functionality. [0004] In addition, in the modular constructions systems of structures, there are always additional elements required to form reinforcements, to form beams with a certain incline, etc., all of which makes the construction of the actual structure more costly, requiring additional welding and other means to set different elements and parts used. [0005] In any case, there are no known modular constructions systems of structures with the characteristics that correspond to the one defined in this patent for invention being requested. DESCRIPTION OF THE INVENTION [0006] The system proposed first shows the characteristic of building structures without the need for welding, and only using screw elements. [0007] More specifically, the modular system is made up grooved profiles, in some cases straight, in other cases on an angle, in other cases with side grooved formations, etc, to allow the joining of tubular arms that will form beams, struts, braces, etc, where those arms will always remain joined together using screws that attach two grooved profile parts together, showing side wings with the holes for the passing of setscrews. [0008] Also, in specific cases, one of the side of the grooved profiles becomes a flexible assembly for the arms which can form beams, and even struts and/or braces, with the possibility of allowing these tubular arms to be placed at any angle and therefore form sloping parts of the structure to form roofs, form configurations in a dihedric angle in the actual roof covering or roofing, etc. [0009] As such, it involves that the modular building of structures is based on forming nodes to which the tubular arms are attached making up the actual structure, with tubular arms that can form, as previously indicated, struts or columns, beams, braces, etc according to its availability with regard to the nodes. [0010] Each node shall be formed by the grooved profiles, which in some cases will be continuous and will attach to themselves by way of a clamp with screws passing through side holes in these grooved profiles, while in other cases the profiles will form an angle together, but always in the same piece for each profile, as well as showing different sections according to the directions in the three axes X, Y, Z, o bien en T en cruz, etc. [0011] The different configuration of the nodes allows to place two tubular arms in adjacently, meaning aligned longitudinally, or having two tubular arms forming a 90° angle together, or form nodes that have three perpendicular arms together according to axes X, Y, Z form nodes where four arms meet, that may be fixed and perpendicular with each other, or two of those forming an angle and the other two articulated to form different angles of the respective tubular arms that join in an articulated way to the respective profiles. [0012] There may also be nodes formed that have five perpendicular arms coming together and even one or two of them articulated to form different angles. [0013] Another characteristic of the system is that there may be crossed profiles, with two grooved profiles available in opposite direction and with a perpendicular orientation, to establish the crossing of the two tubular arms that overlap in this node. [0014] Another layout is for the nodes lo be able lo form an element of articulation or setting of the lower end of the tubular arms determining columns or struts, meaning for fastening to the floor using a plate where the grooved profile is strengthened where the end of the tubular arm making up the strut or column articulates. [0015] Using all of these variants of nodes, structures may be formed with various natures, meaning with different configurations for buildings of all types, and also to form furniture of any type as well, etc. [0016] Lastly, in any case the parts or elements that participate in the nodes and the setting of the corresponding tubular arms, is only done with the use of screws, without the need for welding or any other element other than the profiles of one form or another to determine the corresponding nodes and from the tubular arms themselves to form struts or columns, beams, braces, etc. DESCRIPTION OF DRAWINGS [0017] To complement the description below and with the purpose of helping to better understand the characteristics of the invention, according to a preferred example of its practical use, as an integral part of this description are included a set of drawings where the following has been represented, including but not limited to: [0018] FIG. 1 .—Detailed view of the two contiguous tubular arms joined together, aligned longitudinally, which remain joined with a clamp formed by two facing grooved profiles and through which grooves the fastening or holding of the ends of these tubular arms is determined. [0019] FIG. 2 .—Shows a perspective view of the node in a right angle to join two perpendicular tubular arms together. [0020] FIG. 3 .—Shows a perspective view of the profiles that participate in a node with three tubular arms according to axes X, Y, Z. [0021] FIG. 3 bis.—Shows an exploded view of the two profiles that make up the fastening method in the node of FIG. 3 . [0022] FIG. 4 .—Shows a perspective view of a node with three perpendicular tubular arms coming together, but one of the is articulated to be able to be placed in different angles. [0023] FIG. 5 .—Shows a perspective view of a node with (our tubular arms, two of which are articulated laterally. [0024] FIG. 6 .—Shows a perspective view of a node with three “T” tubular arms. [0025] FIG. 6 bis.—Shows an exploded view of the two profiles that define the means of fastening the node of FIG. 6 . [0026] FIG. 7 .—Shows a perspective view of a node with four arms, three of them in “T” and the fourth is articulated perpendicularly to be able to occupy different angled positions. [0027] FIG. 8 .—Shows a perspective view such as the previous figure but in this case with a node with four perpendicular tubular arms together, all fixed with not articulation. [0028] FIG. 9 .—Shows a perspective view of a node with live tubular arms, three of them in “T”, a fourth perpendicular to the previous ones and a fifth arm opposite to the one previously mentioned but articulated with respect to the node group. [0029] FIG. 10 .—Shows a perspective view of a node with two crossing tubular arms. [0030] FIG. 11 .—Shows a perspective view such as the figure above, where one of the tubular arms is articulated. [0031] FIG. 12 .—Shows a perspective view of a node for floor fastening. [0032] FIG. 13 .—Shows a perspective view of a node with two tubular arms, one is articulated in an intermediate area of another fixed profile. [0033] FIGS. 14, 15 and 16 .—Show, as an example, different perspective views of structures obtained based on the building system that is the object of the invention. PREFERRED EMBODIMENTS OF THE INVENTION [0034] As can be seen in the figures referenced, the modular structure building system that is the object of the invention, is based on using a series of nodes with different configurations, used as elements to join tubular arms ( 1 ) that along with the indicated nodes will make up the structure itself. [0035] In that regard, FIG. 1 shows how the node is formed by a pair of grooved profiles ( 2 ), that they are straight and have side wings ( 3 ) with holes for the passing of the corresponding tightening screws ( 4 ) to establish a type of clamp between the two profiles ( 2 ) left facing with their grooves and between them the tubular arms ( 1 ) to join, so that as they are shown in FIG. 1 the node that form the two grooved profiles ( 2 ) facing together, between them are two tubular arms ( 1 ) fastened and aligned longitudinally with each other. [0036] FIG. 2 shows an angled node to join two tubular arms ( 1 ) together, forming a right angle together, for which the profiles, in this case referenced with ( 2 a ) have an angled configuration, same as its corresponding side wings ( 3 ), which are also equipped with holes for the fast passing of lightening screws ( 4 ) that will fasten and lighten both profiles ( 2 a ) together to hold and joining the tubular arms ( 1 ) at a right angle as can be seen in this FIG. 2 . [0037] In FIG. 3 the fastening of the profiles ( 2 b - 2 b ′) define three perpendicular branches together, according to the axes of coordinates X, Y, Z, where the corresponding side wings ( 3 ) are also affected with holes for the passing of fastening and tightening screws ( 4 ) to obtain the fastening and joining of three tubular arms ( 1 ) together according to axes X, Y, Z. [0038] In all mentioned cases, as well as in the ones to be shown below, the profiles ( 2 , 2 a, 2 b , . . . ) will always be grooved and will have their corresponding side wings ( 3 ) with their holes for the passing of tightening or fastening screws ( 4 ) of the tubular arms ( 1 ) that will make up the structure. [0039] FIG. 4 , shows another node, like the one in FIG. 2 , but in this case with a profile ( 2 ″) strengthened with welding or with another adequate means on the cross section of the grooved configuration of the profiles ( 2 a ), with that profile ( 2 ′) forming a one-piece body with one of the profiles ( 2 a ) and its grooves facing out, to obtain the joining of the end of a tubular arm ( 1 ) that in this case stays mounted in an articulated way with the screw ( 4 ) that acts like a pivoting axis for the tubular arm ( 1 ), allowing for it to be located with any angle with respect to the nodes that form the profiles ( 2 a ). [0040] FIG. 5 shows a variant for FIG. 4 , so that in this case, instead of having one sole profile ( 2 ′) for the mounting and articulation of a tubular arm ( 1 ), there are two grooved profiles ( 2 ′), opposite each other and on one or the other cross sections of the two profiles ( 2 a ), to establish a means for articulated assembly of the two tubular arms ( 1 ) opposite each other and both articulated to be able to occupy different positions, for which in this case according to FIG. 5 , the node has four tubular arms ( 1 ), two of them forming a right angle together and the other two, perpendicular to the previous ones but articulated to be able to occupy different angled positions. [0041] FIG. 6 shows three arms ( 1 ) joined in a “T”, two of them are aligned longitudinally over the clamp that make up the profiles ( 2 c ), while the third, is left in vertical position as shown in FIG. 6 , and stays fastened with the clamp formed by two grooved profiles ( 2 ″) that emerge from one of the sides of the profiles ( 2 c ). [0042] FIG. 7 shows a variant of ways to perform FIG. 6 , but by including a fourth tubular arm ( 1 ) perpendicular to the previous ones, for which its has been provided that the cross section of one of the profiles ( 2 c ) has a perpendicular profile ( 2 ′) with grooves facing out. with holes facing for the corresponding passing of screws ( 4 ) which makes up the axis of rotation for the fourth tubular arm ( 1 ), allowing to place it in any angle with respect to the nodes that make up the other profiles ( 2 c ), with the three tubular arms ( 1 ) in “T”. [0043] FIG. 8 shows a variant of FIG. 6 , but by including four tubular arms ( 1 ) in the node, three of which are in “T” as shown in FIG. 6 and a fourth perpendicular to the rest, so that from the cross section of one of the grooved profiles ( 2 c ) emerge another pair of profiles ( 2 ″′) one free and the other fixed to the profile ( 2 c ) with welding, forming the corresponding clamp which holds and fastens the end of the fourth tubular arm ( 1 ). perpendicular to the previous ones, by lightening the corresponding screws ( 4 ) over the holes of the side wings ( 3 ) of those profiles ( 2 ″). [0044] FIG. 9 another variant for the method, in this case with a node in which there are live tubular arms ( 1 ), four of them as in those of FIG. 8 and the fifth one is mounted on a grooved profile ( 2 ′) strengthened to the cross section of one of the profiles ( 2 c ), where the tightening and fastening screw ( 4 ) makes up the pivoting axis so that the fifth tubular arm ( 1 ), left articulated and allowing to occupy different angled positions with respect to the node, while the remaining lour tubular arms ( 1 ) are fixed. [0045] FIG. 10 shows a node with two crossing tubular arms ( 1 ), but overlapping each other, for which there are two grooved profiles available that can correspond to the configuration of the profiles ( 2 ), with their grooves facing, but crossing, to allow the overlapping and crossing nature between the tubular arms ( 1 ) that are fastened in an intermediate area of theirs in the node that form these grooved and straight profiles ( 2 ). [0046] FIG. 11 shows a variant of FIG. 10 , but in this case with two grooved profiles ( 2 ′) opposing and forming 90°, fastened with welding so that over these profiles ( 2 ′) using screws ( 4 ) the corresponding tubular arms ( 1 ) are left mounted in an articulated manner, allowing that the upper arm ( 1 ) can swivel in one direction and another and form different angles with respect to the node, opposite to what occurs in the method used in FIG. 10 where the two tubular arms ( 1 ) are fixed. [0047] FIG. 12 shows an example method of a tubular arm ( 1 ) anchored to the floor, using a plate ( 5 ) over which a grooved profile ( 2 ′) is reinforced with a hole in its side sections for the passing of a screw ( 4 ) as a rotating axis of that strutt or tubular arm ( 1 ) while FIG. 13 shows a node formed by two opposed grooved profiles ( 2 ″), one of them for mounting and fastening of a tubular arm ( 1 ) and the other for the articulated assembly of a second articulated arm ( 1 ). [0048] Evidently, in addition to the examples described and shown in the drawings, there may be very different configurations of nodes obtained and the use of the tubular arms, ( 1 ) with respect to these, in some cases fixed and in other cases articulated, in other cases forming nodes with 2, 3, 4, 5 and even more arms, etc. [0049] In any case, based on the nodes mentioned and the assembly of the tubular arms ( 1 ), structures are obtained such as those represented in FIGS. 14, 15 and 16 , among others, as an example, so that the structure ( 6 ) shown in FIG. ( 14 ), includes tubular arms ( 1 ) in strut functions, tubular arms ( 1 ) in upper structure functions, and even lower tubular arms in rigid element functions, and in all cases joined together in the corresponding nodes, referenced in this case with number ( 7 ), even though these nodes can correspond to that of FIG. 2 , to the one shown in FIG. 3 , etc, and these structures ( 6 ) may be used for to build compartments for any building, etc. [0050] The same occurs with the structure shown in FIG. 15 , which includes struts ( 1 ) formed by the corresponding tubular arms, with nodes anchored to the floor and with an upper section, and even with some ends anchored to the wall, all in order to make it possible to make different configurations of buildings, furniture, etc. [0051] Finally, FIG. 16 shows a structure ( 8 ) with struts formed by tubular arms ( 1 ), nodes ( 7 ) to anchor to the floor, and an upper section forming two slopes, as well as transversal porticos always formed by and in all cases by the corresponding tubular arms ( 1 ) located in the nodes ( 7 ), and in each case with the proper configuration so that in this case the structure ( 8 ) is adequate to form a building or construction with a cover that will have two water lines or sloped plans for rainwater drainage.

The system relates to a system for creating junctions for tubular structures. The system is based on provided a plurality of junctions ( 7 ) which are different from each other, formed by pairs of profiles ( 2 ) or ( 2 a ) or ( 2′ ) or ( 2″ ) or ( 2″′ ) secured to each other to form the corresponding junction ( 7 ) and to be able to mount and join tubular arms ( 1 ) that will form the actual structure. Said tubular arms can be longitudinally aligned, can form a right angle between each other, can form T-shaped configurations, and can meet at junctions with four tubular arms ( 1 ), junctions with five tubular arms ( 1 ), and junctions with even more arms, in order to allow any type of structure for different constructions, both in terms of buildings and in terms of furniture, inter alia.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATION [0001] This application is a continuation of U.S. patent application Ser. No. 11/711,391, filed Feb. 27, 2007, which claims priority from United States Provisional Patent Applications 60/776,993 filed Feb. 27, 2006 and 60/849,042 filed Oct. 3, 2006. These applications are herein incorporated by reference in their entirety. BACKGROUND OF THE INVENTION [0002] The present invention relates generally to the field of flush valves in general. More particularly, the present invention relates to dual flush volume flush valves. [0003] Flush valves are used to selectively control the flushing of a urinal or toilet with a certain volume of water. Typically, flush valves include a flexible diaphragm with forms a seal between the inlet and outlet, whereby a disruption of the diaphragm will result in a flow of water into the urinal or toilet. This disruption controls the volume of the flush, and is generally fixed. [0004] Commercial toilets and urinals have traditionally utilized a single flush volume in their operations. This flush volume is designed to provide the maximum amount of water needed that may be needed to clear solid waste products. However, solid waste and liquid waste require different volumes of water. In a single flush system, the higher volume of water necessary to flush solid waste is also used to flush liquid waste, with the result that more water than is necessary is often used. There is a need for a dual flush volume toilet which allows for the use of a lower volume of water when a full volume is not needed to clear waste. [0005] Some prior art flush valves provide for a dual flush. However, such prior art dual flush mechanisms typically rely on modifying the action of the flush handle. This presents a user with a non-standard flushing experience and lessens the likelihood of proper usage. [0006] Due to the ubiquitous nature of urinals and toilets, their operation has become an afterthought for most users. Therefore, there is a need for a dual flush toilet which allows for easy of operation and provides operation and design similar to current commercially used systems. SUMMARY OF THE INVENTION [0007] One embodiment of the invention relates to systems and apparatus for providing more than one flush volume. A user is able to select between a greater and a lesser flush volume, either via manual actuation or automatic actuation. [0008] In one embodiment, the flush device relates to a handle comprising a housing mountable to a valve body having diaphragm valve disposed therein with a stem extended downwardly therefrom. The handle pivotally is mounted to the housing and engagable with the stem via a plunger. The plunger has an outer end for engaging the handle, an inner end for engaging the stem, and a shank therebetween, the plunger being axially slidable through a passage in a bushing. The bushing is positioned between the handle and the valve. The passage comprises a first axis and a second axis, the axes in substantially the same vertical plane and intersecting at a point. The point of intersection is a pivot point of the plunger. Actuation of the handle in a first direction moves the plunger axially along the first axis and actuation of the handle in a second direction moves the plunger axially along the second axis. [0009] In one embodiment, the pivot point is proximate the valve body. In another embodiment the pivot point is opposite the valve body. In one embodiment, the first axis is horizontal and the second axis is tilted either up or down therefrom. In another embodiment, the passage comprises a third axis which is tilted in relation to the first axis opposite the tilt of the second axis. [0010] These and other objects, advantages, and features of the invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below. BRIEF DESCRIPTION OF THE FIGURES [0011] FIG. 1 illustrates a longitudinal cross-section of a valve body; [0012] FIG. 2 illustrates a longitudinal cross-section of the handle assembly; [0013] FIGS. 3A-3F illustrate various handle and plunger arrangement embodiments; FIGS. 3A-3C illustrate embodiments having a pivot point proximate the handle and FIG. 3D-F having a pivot point proximate the valve body; [0014] FIGS. 4A-C illustrate the operation of one embodiment of the invention; [0015] FIG. 5 a illustrates a view along axis A-A of FIG. 1 , illustrating the relative circumferences of the plunger head, the bore at the pivot point, and the opposite end thereof the bore; FIG. 5 b illustrates a perspective partial cut-away view of the plunger and plunger sleeve along axis A-A; [0016] FIGS. 6A-C illustrate the operation of one embodiment of the invention having a manual handle with a bead and a conical plunger head. [0017] FIGS. 7A-C illustrate the operation of one embodiment of the invention having an automatic handle and a conical plunger head. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0018] The present invention relates to a flush valve system having at least two flush volumes. As illustrated in FIG. 1 , the flush valve system 10 of the present invention includes a body 11 having an inlet 12 and an outlet 14 . When installed the inlet 12 is connected to a water supply [not shown] and the outlet 14 is connected to a fixture [not shown] such as a toilet or urinal. A valve member is indicated generally at 16 . The valve member 16 may be any of the various assemblies shown in the art that utilize a plunger and sleeve mechanism. In the illustrated embodiment, the valve member 16 is a valve assembly but it could be otherwise, such as a piston assembly. In one embodiment, the valve member 16 includes a diagram 18 peripherally held to the body 11 by an inner cover 20 . The diaphragm 18 is seated upon a shoulder 22 at the upper end of body 11 by an inner cover 20 . The diaphragm edge 52 of the diaphragm 18 is clamped in this position by the inner cover 20 . An outer cover 21 is attached to the body 11 to hold the inner cover 20 in position. [0019] The valve member 16 , in addition to diaphragm 18 and the relief valve 30 , includes a retaining disk 43 , a refill ring 42 and a flow control ring 44 . The underside of the retaining disk 43 is attached, such as threadedly, to a collar 46 , which in turn is attached, such as threadedly, at its exterior to a chamber flow sleeve 48 which carries the refill ring 42 . The above described assembly of elements firmly holds the diaphragm 18 between the upper face of the refill ring 42 and a lower facing surface of the collar 46 . Above the valve member 16 is a pressure chamber 50 which maintains the valve member 16 in a closed position when the flush valve system 10 is in a resting state, i.e. not being flushed. [0020] The valve member 16 , is closed upon a valve seat 26 formed at the upper end of a barrel 28 . The barrel 28 forms the fluid conduit connecting the valve seat 26 with outlet 14 . The valve member 16 includes a relief valve 30 having a downwardly extending stem 32 , in one embodiment telescopically carrying a movable sleeve 34 . The handle assembly 37 of the present invention is described in further detail below and illustrated in FIG. 2 . In general, the handle assembly 37 includes a handle 38 that actuates the plunger 36 , manually or automatically. Sleeve 34 is positioned for contact by a plunger 36 when operated by a handle 38 . [0021] As is known in the art, when the handle 38 is operated, the plunger 36 will contact sleeve 34 , tilting the relief valve 30 off its seat on the retaining disk 43 . This will permit the discharge of water within the pressure chamber 50 down through the chamber flow sleeve 48 . Inlet pressure will then cause the diaphragm 18 to move upwardly off its seat 26 , permitting direct communication between the inlet 12 and the outlet 14 through the space between the bottom of the valve member 16 and the seat 26 . The raising of the diaphragm 18 also lifts the relief valve sleeve 34 , allowing it to clear the plunger 36 and return to a vertical, non-tilted position even if the user has held the handle 38 in an actuated position. Once the sleeve 34 clears the plunger 36 the relief valve reseats on the retaining disk 43 . As soon as this operation has taken place, the pressure chamber 50 will begin to fill through the filter and bypass orifice 54 in the valve assembly. As flow continues into the pressure chamber 50 , the valve assembly will move back down toward its valve seat 26 and when it has reached that position, the flush valve will be closed. [0022] It will be appreciated that as a result of the interaction of the sleeve 34 , stem 32 , and diaphragm 18 , the position on the sleeve's vertical axis at which the plunger 36 contacts the sleeve 34 as well as the distance the plunger 36 travels after initially contacting the sleeve 34 (generally referred to as “the throw” of the plunger 36 ) control the volume of water that will flow past the diaphragm 18 . Dropping the plunger tip 35 to a lower position will permit the sleeve 34 of the relief valve 30 to clear the plunger tip 35 sooner than is the case when the plunger travels on the horizontal axis and the tip is at position 108 . As a result of the earlier plunger clearance, the relief valve 30 closes sooner. This allows reestablishment of the pressure in chamber 50 sooner, resulting in earlier closure of the diaphragm 18 and lesser volume per flush cycle. So when the user pushes the handle 38 upwardly, the plunger 36 will be angled downwardly and there will be a minimum or reduced flush. When the user pushes the handle 38 in any direction but up, the plunger 36 will move on the horizontal axis and a greater or maximum flush volume will result. Similarly, the opposite motion of the plunger tip 35 results in the opposite effect, i.e. the sleeve 34 is not able to clear the plunger tip 35 until later and thus the relief valve 30 remains open longer. [0023] The handle assembly 37 fits through an opening in the valve body 11 and is retained therein. In one embodiment, the handle assembly 37 is retained on the valve body 11 by a nut 45 . The handle assembly 37 includes the handle 38 having an inner end 39 proximate valve body and an outer end 40 opposite the valve body 11 . The handle 38 includes a face plate 58 at its inner end 39 . The face plate 58 is held within a chamber 61 formed by a handle socket 60 . In one embodiment, the handle 38 is partially disposed within the handle socket 60 . The socket 60 includes an inner end 63 proximate the valve body 11 and an outer end 64 distal the valve body 11 . An inwardly extending flange 62 on the socket's outer end 64 retains the handle face plate 58 . A covering 65 may line the socket chamber 61 and flange 62 . In one embodiment, the inner end 63 of the socket 60 is threaded to the bushing 66 in one embodiment. The skirt 71 is threaded to the socket 60 in one embodiment. The handle assembly 37 may include a handle 38 for manual activation or engagable with an automatic actuation mechanism ( FIG. 7 ). [0024] The bushing 66 has a plunger sleeve 68 defining a bore or passage 78 in the handle assembly 37 and an outer skirt 71 joined by a wall 72 . The passage 78 having an inner end 77 proximate the valve body 11 and an outer end 79 proximate the handle 38 . Further details of the passage 78 will be described below. The inner end 69 of the plunger sleeve 68 has, in one embodiment, a beveled nose 74 that mounts a handle packing or seal 76 . The plunger 36 includes a shank 80 and an inner end 81 proximate the valve body 11 and an outer end 82 opposite the valve body 11 . In one embodiment, a head 83 is positioned on the outer end 82 of the plunger shank 80 . The head 83 interacts with the face plate 58 of the handle 38 . In an exemplary embodiment, the handle assembly 37 includes a biasing mechanism 84 . The biasing mechanism 84 provides force to retain the handle 38 in a neutral (i.e. horizontal) position despite the force of gravity. In one embodiment, a compression spring or other suitable biasing device 84 fits between the bushing 66 and the head 82 to urge the plunger 36 into engagement with the face plate 58 of the handle 38 . [0025] In one embodiment, it can be seen that the diameter of the passage 78 (as defined by sleeve 65 ) is at its smallest, just slightly larger than that of the plunger 36 . Thus, the plunger 38 can slide and tilt freely in the circular opening 92 but it cannot move up, down or sideways appreciably. This contrasts with the oval opening 94 which permits appreciable up and down movement of the plunger at that point. The result of the combination of the passage 78 and the openings 92 , 94 is the plunger 38 can tilt up and down as well as slide axially. [0026] The present invention provides a mechanism to engage the sleeve 34 with the plunger 36 at two or more positions along the vertical axis of the sleeve 34 . FIGS. 3A-F depict several embodiments which provide two or more flush volumes. FIGS. 3A-3C illustrate embodiments having a pivot point 130 proximate the handle 38 . In on embodiment, the handle 38 engages the plunger 36 generally as described above. A movement of the handle 38 pivoting the plunger 36 about pivot 130 such that the inner end of the plunger pivots, resulting in a changed flush volume. [0027] The embodiments illustrated in FIGS. 3D-F have a pivot point 130 proximate the valve body. The positioning of the pivot point at the opposite end of the plunger 36 from the handle 38 results in an increased need for a plunger 36 /handle 38 interface able to create a moment to pivot the plunger 36 . Motion of the handle 38 pivots the plunger 36 about the pivot 130 , resulting in a changed flush volume. [0028] The interface of the handle 38 and the plunger 36 maybe any of the various designs that achieve the movement of the plunger 36 about the pivot point 130 as dictated by statics. As such, the embodiments utilizing at the inner end, i.e. proximate the valve body 11 rather than the handle 38 , generally require a plunger head 83 and or a handle face plate 58 which has a particular shape designed to create a moment. In one embodiment, the plunger 36 of FIGS. 3A and B include head 83 having a flattened conical shape (best illustrated in FIG. 6 ). A downward movement of the handle 38 pivots the plunger upward in this embodiment. The plunger head 83 may comprise any shape to enable the creation of a moment to pivot the plunger about the axis. For example, an alternative embodiment utilizes an inverted flattened conical shape and imparts the opposite relationship between handle 38 movement and plunger 36 pivot, i.e. a downward movement of the handle 38 pivots the plunger 36 downward as well. Thus, the handle 38 /plunger 36 interface maybe selected to provide a specific use profile. [0029] As can be seen in FIGS. 3A-F , the plunger 36 may be provided with a plurality of axes. For example, instead of having the widened opening of the passage at the outside end of the sleeve, it could be at the inner end. Or, instead of having the lowermost edge of the passage be horizontal and the uppermost edge be angled as shown, this arrangement could be reversed. A further alternative is to provide a sleeve passage with a horizontal axis and an angled axis wherein the inner end of the plunger is angled above horizontal. In that case the horizontal travel, caused by an upward actuation of the handle 38 , would provide the lower flush volume. Similarly, the upwardly angled travel, caused by a downward actuation of the handle 38 , would provide the higher volume flush. Some shortening of the relief valve sleeve might be needed in conjunction with this setup. Yet another possible alternate construction of the bushing passage 78 is to make the inside diameter of the bushing passage 78 appreciably larger than the outside diameter of the plunger. This would cause the plunger to tilt somewhat no matter which direction the handle 38 is actuated, but only tilting in the vertical plane would affect the volume of the flush. [0030] In one embodiment, shown in FIGS. 3A and 3D , the plunger includes an axis A-A which is substantially horizontal, similar to traditional plunger 36 arrangements. The plunger 36 of FIGS. 3A and 3D is also provided with an axis B-B which is tilted upward from the axis A-A but remains in the same vertical planes such that axes A-A and B-B are non-parallel and intersect at the pivot point 130 . When the plunger travels along axis B-B, it strikes the sleeve 34 at a higher point on the sleeve's vertical axis resulting in a higher flush volume than if the plunger 36 travels along axis A-A. Thus, for the embodiment of FIG. 3A , a downward motion of the handle 38 results in a maximum flush volume and other motions result in a lesser flush volume. For the embodiment of FIG. 3D , an upward motion of the handle 38 results in a reduced flush volume and a downward or lateral motion results in a maximum flush volume. [0031] In another embodiment, shown in FIGS. 3B and 3E , the plunger includes an axis A-A which is substantially horizontal, similar to traditional plunger 36 arrangements. The plunger 36 of FIGS. 3B and 3E is also provided with an axis C-C which is tilted downward from the axis A-A but remains in the same vertical planes such that axes A-A and C-C are non-parallel and intersect at the pivot point 130 . When the plunger travels along axis C-C, it strikes the sleeve 34 at a lower point on the sleeve's vertical axis resulting in a lower flush volume than if the plunger 36 travels along axis A-A. Thus, for the embodiment of FIG. 3B , an upward motion of the handle 38 results in a reduced flush volume and a downward or lateral motion results in a maximum flush volume. For the embodiment of FIG. 3E , an upward motion of the handle 38 results in a reduced flush volume. [0032] In one embodiment, shown in FIGS. 3C and 3F , the plunger includes an axis A-A which is substantially horizontal, similar to traditional plunger 36 arrangements. The plunger 36 of FIGS. 3C and 3F is also provided with an axis B-B which is tilted upward from the axis A-A and an axis C-C which is tilted downward from axis A-A. All of these axes remain in the same vertical planes such that axes A-A, B-B, and C-C are non-parallel and intersect at the pivot point 130 . When the plunger travels along axis B-B, it strikes the sleeve 34 at a higher point on the sleeve's vertical axis resulting in a higher flush volume than if the plunger 36 travels along axis A-A or axis C-C. When the plunger travels along axis C-C, it strikes the sleeve 34 at a lower point on the sleeve's vertical axis resulting in a lower flush volume than if the plunger 36 travels along axis A-A or axis B-B. If the plunger travels along axis A-A, the flush volume is between the volume triggered by a path along B-B and that trigged by a path along C-C. Thus, for the embodiment of FIG. 3C , a downward motion of the handle 38 results in a maximum flush volume and an upward motion results in reduced flush volume. [0033] The embodiments shown in FIGS. 3A , 3 B, 3 D, and 3 E exhibit an orientation of the handle 38 to the plunger 36 and to the valve body 11 . For embodiments where the plunger 36 has a horizontal axis A-A and either a upward tilted axis B-B or a downward tilted axis C-C, the handle 38 and plunger 36 must be orientated correctly with each other and with the bushing 66 and valve body 11 to achieve the appropriate tilting of the plunger 36 within the passage 78 . That is, because of the need to create a moment in order to tilt the plunger 36 , the plunger 36 and or handle 38 include a specific profile. Since this tilt of the axis (i.e. the plunger 36 only occurs upward ( FIGS. 3A and 3D ) or downward ( FIGS. 3B and 3E ), only one direction of operation of the handle 38 need achieve a moment. [0034] However, in some embodiments of the handle assembly 37 , the orientation of the handle 38 to the plunger 36 and to the valve body 11 is irrelevant to the flush volume, i.e. assembly is orientation neutral. Embodiments with no orientation provide for simpler assembly and maintenance. As opposed to FIGS. 3A-B and 3 D-E, the embodiments of FIGS. 3C and 3F provide for both upward and downward tilting and thus require a handle 38 /plunger 36 interface that is capable of creating a moment regardless of whether the handle 38 is moved up or down. Such an orientation-free design is particularly useful where it is desired to have an ambidextrous flush valve assembly so that the handle 38 may be either left-handed or right-handed, particularly where the handle 38 is automatically actuated (See FIGS. 7A-C ). [0035] Turning now to FIGS. 4A-C , details of the bushing passage 78 of one embodiment (that illustrated generally in FIG. 3F ) are shown. The passage 78 can be considered to be defined by a plurality of bores, such as first and second bores 88 and 90 extending through the plunger sleeve 68 . Each bore corresponds with an axis as described above. For example, first bore 88 corresponds with axis A-A and second bore 90 corresponds with axis B-B (a third bore 91 would correspond with axis C-C). The bores 88 , 90 are preferably substantially centered on the same vertical plane. The first bore 88 is horizontal and defines a horizontal plunger travel axis A. The second bore 90 is not horizontal. The second bore 90 is tilted from the end adjacent the handle 38 to the end adjacent the valve member 16 at the outer end 70 of the plunger sleeve 68 and defines an angled plunger travel axis B. The second bore can be considered a tilted portion of the bushing passage 78 . The bores preferably each have a diameter slightly greater than that of the plunger shank 80 . The bores overlap and merge together at the inner end 69 of the plunger sleeve 68 so that they define a substantially circular opening 92 at the inner end 69 . At the outer end 94 , the bores' divergent axes result in an oval-shaped opening. FIG. 5A illustrates a view along axis A-A illustrating the relative shape and positions of the two openings. FIG. 5 b illustrates a perspective partial cut-away view of the plunger 36 and plunger sleeve 68 along axis A-A. In one embodiment ( FIGS. 3B and 3E ), at the outer end 70 of the plunger sleeve, the second bore 90 is above the first bore 88 . In another embodiment, the outer end of the second bore 90 is below the first bore 88 . As seen in FIG. 5 , the opening 94 at the outer end 70 of the plunger sleeve 68 includes an upper arcuate portion 96 , a lower portion 98 , and a pair of extension portions 100 and 102 joining the upper and lower arcuate portions. The result is a somewhat oval, although not strictly elliptical, shaped opening 94 . As seen on FIG. 5 , the opening 92 at the inner end 69 of the plunger sleeve 68 includes an upper arcuate portion 104 , a lower arcuate portion 106 . In one embodiment the height of the extension portions at the opening has shrunk to essentially zero so the arcuate portions 104 and 106 join one another. [0036] The operation of one embodiment of the handle assembly 37 will now be described. In one embodiment, shown in FIGS. 3D and 3F , downward motion of the handle 38 results in a reduced flush volume and an upward motion results in a standard or larger flush volume. The downward movement of the handle 38 causes the face plate 58 to pivot about the upper portion of the plate (which remains in contact with the socket flange 62 ) with the lower portion of plate 58 moving to the right. This places a force F handle on the plunger 36 , the plunger 36 remains centered on the horizontal plunger travel axis A-A. The handle 38 in an actuated position where it has been moved up by a user. Upward movement of the handle 38 causes the face plate 58 to pivot about the lower portion of plate with the upper portion of plate 58 moving to the right. This places a force F handle on the upper portion of the plunger head 58 . With noted forces F bushing on the plunger 36 , the plunger 36 tilts upward at the left end and downward at the right end, taking the plunger 36 into the second bore 90 where it is aligned with the angled plunger travel axis B. This lowers the inner tip of the plunger 36 . [0037] As will be evident from the above description, the second bore 90 provides a tilt portion of the bushing passage 78 . This produces a non-symmetrical configuration of the passage, as compared to having only a simple, single horizontal bore at 88 . In order to provide the vertical plunger tip drop D with the attendant lower flush volume, the bushing 66 must be installed on the valve body such that the first and second bores 88 , 90 re oriented in a generally vertical plane with the second bore 90 on top. However, since the bores are in the interior of the bushing 66 an installer can see neither the bores nor the indicia 86 once the bushing 66 goes into the valve body. The present invention solves this problem by providing an externally-visible mark or indicator 85 showing the location of the second bore. The wall 72 may have indicia 85 thereon which indicates which side of the busing 66 has an angled axis as described above. The indicia 85 may be in the form of a depression 86 in the wall. The indicia 85 will assist the installer in orienting the bushing 66 properly. Other indicia 85 may be used without varying from the scope and purpose of the invention. In the illustrated embodiment the mark 85 is simply a line which may be suitably printed on a label that is attached to the exterior portion 112 of the socket 60 . The label may optionally carry additional graphics 116 to instruct the user regarding the availability of the reduced flush alternative. Instead of a label, the mark 114 could be engraved or otherwise formed directly on the socket. The mark 114 can be used in conjunction with the indicia 86 on the bushing 66 . That is, at the time of installation of the handle assembly 37 on to the valve body 11 , the installer can look to ensure that the mark 114 is rotationally aligned with the indicia 86 and then make sure that the mark 114 is at the top of the handle assembly 37 when the nut 45 is tightened. This will result in the bushing passage 78 having the proper orientation relative to the valve body 11 and relief valve sleeve 34 . Further assurance of proper alignment may be added by placing a flat 118 on the external flange of the bushing 66 . Aligning the mark 114 with the flat 116 during assembly of the handle 38 and then placing the mark at the top of the handle 38 during installation of the handle assembly 37 will result in the correct orientation. [0038] In one exemplary embodiment actuation of the handle 38 downward results in a reduced flush volume and actuation of the handle 38 upward results in a standard flush volume. It will be appreciated that this orientation may be reversed based on the desired manner of operation of the water closet. In one embodiment shown in FIG. 6 , the plunger head comprises a tapered conical head and the handle face plate 58 includes a bead 61 . The bead provides a discrete contact point to engage the conical head. The placement of a bead around a circumference of the faceplate results in the handle 38 having no discrete orientation in relation to the plunger 36 , thus providing for easier and more error free assembly. [0039] In this embodiment, actuation of the handle 38 in any direction other than upward or downward results in a reduced flush volume that depends on the exact position of the handle 38 during actuation. The plunger 36 is provided with a tapered head 56 having a substantially conical shape where the diameter is much greater than the height. At least one protrusion 60 , such as a bead 61 , engages the conical surface of the tapered head 56 when the handle 38 is actuated. In operation, actuation of the handle 38 results in the plunger 36 tilting in the opposite direction of the motion of the handle 38 . For example, where the handle 38 is actuated upwards, the bead 61 engage the top portion of the conical surface, exerting force sufficient to both move the plunger 36 laterally to engage the stem and also to pivot the plunger 36 in relation to the resting plane so that the plunger 36 strikes the stem at a position above the resting plane. The higher striking point of the plunger 36 on the stem results in the valve seat being displaced longer, thus providing a longer flush, i.e. more volume. Likewise, the opposite motion of the handle 38 results in the opposite impact on the flush volume. [0040] The foregoing description of embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the present invention. For example, while the present invention has primarily been described in regard to on embodiment of a valve member, it will be appreciated that various other embodiments of valve members may be utilized without departing from the spirit and scope of the invention. The embodiments were chosen and described in order to explain the principles of the present invention and its practical application to enable one skilled in the art to utilize the present invention in various embodiments, and with various modifications, as are suited to the particular use contemplated.

A handle assembly for providing dual flush functionality to a flush valve. The handle assembly comprising a handle and a plunger engagable with each other. The plunger axially slidable in a bush disposed between the handle and the flush valve. The bushing having a passage for receiving the plunger. The plunger having a first and a second axis along which the plunger may travel through the passage. Movement of the handle moves the plunger from first axis to the second axis wherein actuation of the flush valve by the plunger along the first axis results in a different flush volume than actuation along the second axis.

You are an expert at summarizing long articles. Proceed to summarize the following text: This application claims the benefit of U.S. Provisional Application No. 60/060,087 filed Sep. 26, 1997. BACKGROUND OF THE INVENTION This invention relates generally to a refrigerator for a recreational vehicle (RV) where living space is limited and the flexibility of a refrigerator that can be opened and closed from different sides is desirable. More particularly, the refrigerator of this invention is provided with an actuator member in a prominent place on the refrigerator door. Use of the actuator member manifests a setting of "left", "right" or "locked" for the door. The RV refrigerator of this invention is also advantageously used because it has the ability to have its door readily removable from the refrigerator body whenever this is desired. SUMMARY OF THE TNVENTION The present invention provides a door for closing an opening in the cabinet of a refrigerator, which door can be selectively opened in either one of two directions. To accomplish this, the opening in the cabinet is provided with a first set of hinge pins along one side of the opening and a second set along the opposite side. The door is provided with means for selectively engaging either the first set or the second set of hinge pins to form the hinge mounting either on a first or second side of the door so that the door may be selectively opened in either of two different directions. The door is provided with a readily accessible actuator member for shifting the engagement means into engagement with either of the first or second sets of hinge pins. In the preferred embodiment, the engagement means comprises a pair of slide members mounted for sliding movement on a support member between a first position entrapping a hinge pin received in a recess on one side of the door to a second position entrapping the hinge pin received in a recess on the opposite side of the door. In this invention, a refrigerator cabinet is provided with an access door which can readily be manipulated so that it can swing open from one or the other sides of the refrigerator cabinet. This enables maximum use of the limited space in the recreational vehicle in which the refrigerator is installed. The refrigerator cabinet is provided with hinge pins at the corners of the cold compartment, the upper and lower pins on the left hand side of the compartment are aligned to provide a hinge axis and the hinge pins on the right hand side of the compartment are similarly positioned to provide a vertical pivot axis on the right hand side. Actuating slides are provided at the top and bottom ends of he door for coaction with the hinge pins to mount the door so that it will pivot around the desired axis. The actuating slides are connected so that they move in unison and the user can quickly select opening of the door from either side or lock the door in a travel position. The inside of the refrigerator door is commonly used for storing bottles, cans and other similar containers. The storage articles add to the weight of the door so that there is a tendency of the door to sag making it difficult to achieve an air-tight closure when the door is closed. In the RV refrigerator of this invention, cam and cam follower assemblies are installed on the bottom side of the door and the lower hinge pins to insure quick lifting of the door when it is opened so that when it is subsequently swung toward its earlier closed position, it will automatically return to the closed position. Further objects, features and advantages of this invention will become apparent from a consideration of the following description sand the appended claims when taken in connection with the accompanying drawing. BRIFF DESCRTPTION OF THF DRAWTNGS FIG. 1 is a perspective view of the RV refrigerator of this invention; FIG. 2 is a plan view of the upper slide member in a position moved to the left to mount the door on the hinge pins on the left side of the refrigerator cabinet; FIG. 3 is a plan view similar to FIG. 2 showing the upper slide member in a center position in which the upper and lower slide members are locked on the hinge pins so that the closure door for the cabinet is maintained in a closed position, usually desirable when the RV is moving; FIG. 4 is another plan view of the upper slide member, showing the slide member in its position moved to the right in which the cabinet door is mounted on the hinge pins on the right hand side of the cabinet thereby enabling opening of the refrigerator door in a clockwise direction about an axis extending vertically through the right hand hinge pins; FIG. 5 is an enlarged perspective view of a hinge pin at the lower end of the door and provided with a cam for lifting the door in response to opening movement of the door; FIG. 6 is a fragmentary perspective view of the lower corner of the RV refrigerator door illustrating the location of the follower for the cam shown in FIG. 5 and illustrating the position of the cam relative to the follower; FIG. 7 is a perspective view of the cam and follower shown in FIG. 6, illustrating the relative positions of the cam and follower when the refrigerator door is closed; FIG. 8 is an elevational view of the cam and follower in the position shown in FIG. 7; FIG. 9 is a perspective view like FIG. 7 showing the follower rotated to its uppermost position on the cam; FIG. 10 is an elevational view of the cam and follower in the relative positions shown in FIG. 9; FIG. 11 is a bottom view of the cam follower; and FIG. 12 is a sectional view, partly diagrammatic, as seen from substantially the line 12--12 in FIG. 1 for the purpose of showing the actuator for the slide members and the upper and lower slide members which are connected so that they move in unison. DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the drawing, the RV refrigerator of this invention, indicated generally at 10, is shown in FIG. 1 as including a cabinet 12 which encloses a cold compartment 14. Access to the cold compartment 14 is achieved by opening the door 16 which is mounted on the cabinet 12 for movement between open and closed positions. The door 16 is illustrated in FIG. 1 in which might be called a half-open condition. A pair of door support brackets 18 are secured to the top and bottom sides of the cabinet 12, each bracket 18 terminating at its ends in forwardly extending legs 24. The legs 24 function to position a pair of left side hinge pins 20 and a pair of right side hinge pins 22 in positions spaced forwardly from the front wall 26 of the cabinet 12. The hinge pins 20, only one of which appears in the drawing, are vertically aligned on the left hand side of the compartment 14 and the hinge pins 22 on the right hand side of the compartment 14 are similarly aligned. Thus, the hinge pins 20 and 22 define axes 28 and 30 of rotation for the door 16 which can be mounted so that it can swing outwardly away from the cabinet front wall 26 about either the left hand axis 28 or the right hand axis 30. The door 16 is provided at its upper and lower ends with hinge control assemblies 32 and 34 (FIG. 1) which can be adjusted to provide for either left hand hinging of the door 16 on the hinge pins 20 or right hand hinging on the hinge pins 22, as shown in FIG. 1. Each of the hinge control assemblies 32 and 34 includes an actuating slide member 36 shown in FIGS. 2, 3 and 4. FIG. 2 illustrates the position of an actuating slide member 36 in which it has captured the hinge pins 20 so that the slide member 36 can rotate about the axis 28 of the hinge pins 20 but cannot be separated from its support on the hinge pins 20. Conversely, the hinge pins 22 are in a clearance relation with the slide member 36. This is due to the fact that the slot 38 at the end of the bar 36 adjacent the hinge pin 20 is in a coupled position with the hinge pin 20. Conversely, the slot 40 at the other end of the slide member 36 is in a clearance relation with the hinge pin 22. An actuator member 42 (FIGS. 2 and 12) on the upper end of the door 16 is slidably mounted on a plate member 44 on top of the slide member 36 so that the actuator 42 can move the slide 36 between the extreme positions shown in FIG. 2 and FIG. 4. An actuator link 46 is secured by a pin 48 at one end to the actuator member 42. At its other end, the link 46 is secured to the upper end of a shaft 50 which is connected at its lower end to another actuator link 46 connected to the slide member 36 in the lower hinge control assembly 34. This connection of the upper and lower slide members 36 with the shaft 50 assures unified movement of the upper and lower slide members 36. In the event it is desired to have the door 16 pivot about the right hand axis 30, the actuating member 42 is moved to the right to the extreme position shown in FIG. 4 in which the slot 38 is moved to a clearance position with the left hinge pin 20 and the slot 40 is moved to a position in which the hinge pins 22 are captured in the slots 40 so that the door 16 can pivot about the axis 30. FIG. 3 illustrates the result of positioning the actuator 42 in a neutral position in which both the hinge pins 20 and the hinge pins 22 are positioned in the slots 38 and 40 blocking movement of the slide members 36 in a direction away from the front side 26 of the cabinet 12. Thus, in the FIG. 3 position of the actuator, the door 16 is locked in a closed position during travel of the recreational vehicle so that the door 16 does not inadvertently fly open. In the open position of the refrigerator door 16 the entire weight of the door 16 is on the support bracket legs 24 at the supported end of the door 16. This causes the door 16 to sag at its free end. To prevent door sag from interfering with door closing, cams 60 are provided on the hinge pins 20 and 22 (FIG. 5) at the lower end of the cabinet 12 and cam followers are provided on the bottom corners of the door 16. The cams 60 on the hinge pins 20 and 22 are identical so only the one for the lower hinge pin 22 is illustrated in FIG. 5. The cam 60 is secured to the leg 24 of the bracket and has an upwardly inclined step surface 62, having portions 62a and 62b which extend between lower and upper surfaces 63 and 65. The cam portions 62a and b are of a twisted shape so as to enhance contact with a cam follower 64. It should be pointed out that only one of the cam surface portions 62a and b is used in each cam 60. Each cam 60 is constructed as shown in FIGS. 5 and 10 for efficiency of manufacture. It is easier to make one cam 60 for both pins 20 and 22 than it is to make special cams for each. The hinge control assembly 34 at the lower end of the door 16 is provided with the cam followers 64 at positions in which a follower 64 will interact with a cam 60 at the axis 28 or 30 which is being used as the pivot axis. Accordingly, the lower side of the hinge control assembly 34 on the door 16 has a follower 64 secured to it and extending downwardly into engagement with a corresponding cam 60, as shown in FIG. 7. Each follower is of U-shape having a base 66 and legs 68 on opposite sides of a slot 70. The hinge pin 20 or 22 is positioned in the slot 70 between the legs 68. FIGS. 7 and 8 illustrate the relative positions of the cam and cam follower when the door 16 is closed. As shown in FIG. 11, the inclined surface 72 on the cam follower 64 has portions 72a and 72b (FIG. 11) which are twisted like the cam surfaces 62a and 62b, so as to follow the corresponding inclined surface portions on the cam 60. The areas 74 (FIGS. 5 and 11) on the cam 60 and follower 64 are rounded surfaces which smooth out the movement of the follower on the cam. As the door 16 is opened, the first few degrees of movement will force the follower 64 to move up the cam surface 62b from the position shown in FIGS. 7 and 8 to the position shown in FIGS. 9 and 10. In this position, the cam follower 64 rests on the higher surface 65. As the door is closed, the follower moves progressively down the incline 62 in the last few degrees of movement to return to the positions of the cam and follower shown in FIG. 7. In the event the door 16 is to be removed from the cabinet 12, it is only necessary to move the door 16 to the partially open position shown in FIG. 1 with the actuator slide 36 in the position shown in FIG. 4. With the door in the partially open position shown in FIG. 1, it is only necessary to move the actuator 42 from the position shown in FIG. 4 to the position shown in FIG. 2 in which the hinge pins 22 are uncoupled from the slide member 36 so that the door can simply be lifted off the hinge pins 22. This is an advantageous feature of the invention which plays an important role in the efficient assembly of an RV with an RV refrigerator such as the one shown at 10 in the drawing. At the time that the RV is being assembled, it is advantageous to be able to install the RV refrigerator without concern as to whether or not other arrangements on the other side of the vehicle would dictate use of the refrigerator with the door in a particular position. The present invention enables the RV manufacturer to install the cabinet 12 without the door 16 and wait until the RV is to be sold before the door 16 is mounted on the cabinet 12. It can thus be seen that this invention provides an RV refrigerator which can be expeditiously installed in a new or used RV without causing the interior of the RV to be unduly affected by the installation of the refrigerator.

A refrigerator for RVs comprising an upright cabinet with an internal cold compartment and a door member mounted on the cabinet for closing said compartment, two pairs of upright hinge pins on the cabinet on opposite sides of the door enables the door to swing from both right and left sides of the cabinet. A single actuator is provided for putting the door from a left swing to a right swing and vice versa. In addition, the actuator can secure the door on the cabinet during RV travel. It can also enable easy removal of the door from the cabinet. Cams and cam followers are associated with the cabinet and the door to cause the door to be lifted when opened and lowered when closed to assure easy opening and closing of the door.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION [0001] The invention relates to floor coverings, more particularly, to floor coverings made of natural stone or porcelain with a mechanical locking system. BACKGROUND OF THE INVENTION [0002] Natural stone is an excellent product for flooring tile slabs because it is composed of a hard core as well as being water proof and 100 per cent moisture resistant. [0003] The most common difficulty when installing natural stone tile slabs, is to, accurately, install the tile slabs in such a way, that the corners of four tile slabs align without visible curves after installation in a certain order, therefore avoiding different widths between said tiles. Other disadvantages are the preparation of the subfloor which, needs to be free from indentations, the necessary use of cement and adhesives, another disadvantage is the grout between tile slabs in which stains dirt and grime are impregnated and therefore difficult to maintain clean. Besides the disadvantages mentioned, the traditional installation process is time-consuming and expensive, requiring the use of specialized labor. [0004] Unlike wood based products, the natural stone and porcelain floor tile slabs provide core stability and, as mentioned, is 100 per cent moisture resistant. [0005] Due to said advantages, the inventor recognized the need to integrate a mechanical locking system to facilitate the installation process without the need for cement, adhesives and grout. Over the years several flooring products, of other then natural stone, have incorporated mechanical locking systems. [0006] Therefore, the inventor recognized the potential of the natural stone core and invented a form of incorporating the mechanical locking system in a manner that is cost-effective and technically viable by cutting horizontally into the stone core on all four sides of tile slabs and inserting pre-milled polyvinyl chloride couplings, thus obtaining a tight lock without excess movement on the locking connection. [0007] Therefore, the inventor, by introducing the mechanical locking system, makes natural stone tile slabs more accessible to the flooring trade and to the home owner, without the use for cement, adhesives and grout. Another important characteristic is to the environment. Stone is an environment friendly flooring product with an adhesives free installation. SUMMARY OF THE INVENTION [0008] The inventor has been involved in the flooring market for many years and has seen many changes over the years with new products coming into the market and traditional products becoming more popular. Stone is considered to be an excellent floor covering but not yet considered a floor covering that can be easily installed due to the need for cement, adhesives and grout. [0009] The inventor recognized that transforming a natural stone product more accessible to the flooring trade with easier installation would be challenging, but its determination led to the invention. The advantages are overwhelming. The installation without cement, adhesives and grout is the installation method of the future for natural stone coverings. With the mechanical locking system mentioned allows the professional or the homeowner to accurately align all four corners of the tile slabs simply by clicking each tile slab into place, without the use of grout in between each tile slab. The sub floor preparation is also simplified due to the tile slabs integrated backing layer that will not only insulate said tile slabs but will allow the tile slabs to be installed even if the sub floor has some imperfections, according to the invention. [0010] Natural stone is an environment friendly flooring product. Where no adhesives are used during the installation process therefore, considered environment friendly. An insulation backing layer made of cork or of a syntactic material that is incorporated to the underside of the tile slabs provides a comfortable underfoot feeling, as well as, having acoustical and thermal advantages. [0011] In summary, by incorporating into natural stone tile slabs the referred mechanical system and a backing layer, will give the floor covering trade a recognized floor covering that is water proof and can be installed by professionals and or homeowners alike. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0012] FIG. 1 is a schematic diagram showing a side view of one embodiment with couplings (A 6 , A 5 ) jointed to the natural stone core (A 4 ) and tile slab ( 01 ), according to the invention. [0013] FIG. 2 is a schematic diagram showing a side view of another embodiment with couplings (A 8 , A 9 ) jointed to the natural stone core (A 4 ) and tile slab ( 01 ), according to the invention. [0014] FIGS. 3 and 4 are diagrams showing sectional views of the embodiments of the natural stone tile slab ( 01 ) connecting together, according to the invention. DETAILED DESCRIPTION OF THE INVENTION [0015] The invention describes the manner in which natural stone tile slabs ( 01 ) consisting of a natural stone core (A 4 ) can be illustrated without the use of cement, adhesives and grout. The invention will also show the coupling parts (A 6 , A 5 , A 8 , A 9 ) that connect the tiles together by mechanical locking means and explain in more detail the manufacturing process. Further, a backing layer ( 14 ) that is jointed to the underside of the tile slabs, create a comfortable underfoot feeling as well as an environment friendly installation, according to FIGS. 1 , 2 , 3 and 4 and as describes hereafter, according to the invention. [0016] The invention is intended for all natural stone core (A 4 ) tile slab floors ( 01 ), but generally it can also be applied, such as to porcelain tile slab floor coverings. It is also known that all natural stone tile slabs and porcelain ( 01 ) floor coverings are applied using cement, adhesives and grout. [0017] Common installation practices for natural stones tile slabs ( 01 ) have many disadvantages; floors are installed, using cement and adhesives to secure the tile slabs to the sub floor and the use of grout in between each tile slab. Another disadvantage is the installation time needed and the use of adhesives which may contain volatile organic compounds (VOCS). [0018] The invention aims to improve natural stone floor covering ( 01 ) installation method, without the use of cement, adhesives and grout and also shows the advantage that mistakes are not committed during installation. [0019] The invention describes the manner in which natural stone tile slab ( 01 ) can be installed by mechanical locking means, without the use of cement, adhesives and grout. The couplings (A 6 , A 5 , A 8 , A 9 ) are made from polyvinyl chloride, hereby noted that said couplings are not part of the natural stone core (A 4 ), and not part of the floor covering surface ( 08 ) but only part of the mechanical locking system. Therefore connecting said tile slabs ( 01 ). [0020] The Polyvinyl chloride coupling parts (A 6 , A 5 , A 8 , A 9 ) are realized and manufactured in one piece only and jointed to the natural stone core (A 4 ) as one piece with dimensions of 3 mm to 38 mm in depth or thickness and 3 mm to 38 mm in width. Therefore it is hereby noted that said couplings (A 6 , A 5 , A 8 , A 9 ) are only part of the mechanical locking system and not part of the surface area of said natural stone tile slabs ( 01 ). Said coupling parts (A 6 ,A 5 ,A 8 ,A 9 ) are provided with integrated mechanical locking means which prevent the drifting apart of two coupled tile slabs into a direction perpendicular to the related edges; these coupling parts (A 6 ,A 5 ,A 8 ,A 9 ) are connected in such a manner that they exclude excess movement therefore, improving the installation method. [0021] The coupling parts (A 6 , A 5 , A 8 , A 9 ) provide for a perfect connection between adjacent tile slabs that can be guaranteed, without shrinkage of the floor surface. Said coupling parts (A 6 , A 5 , A 8 , A 9 ) are provided at the four sides, made of one single section of polyvinyl chloride, or either of another construction than described above or not, but not of the same core material (A 4 ) of the tile slabs ( 01 ). [0022] The tile slabs ( 01 ) are connected at least at the edges of two opposite sides with coupling parts (A 6 , A 5 , A 8 , A 9 ), which will allow for adjacent tile slabs ( 01 ) to connect to each other without drifting apart. Furthermore, all embodiments of couplings elements (A 6 , A 5 , A 8 , A 9 ) can be applied on the long side as well as the short side. The mechanical locking couplings elements (A 6 , A 5 , A 8 , A 9 ) are provided with inclined manner, according to a direction which simplifies the snapping-together effect. [0023] In addition the invention refers to a resin type sealant ( 15 ) that is applied where the couplings joints (A 6 , A 5 , A 8 , A 9 ) connect together as described in the manufacturing process for moisture protection as outlined ( 13 ), according to the drawings [0024] Furthermore the polyvinyl chloride couplings (A 6 , A 5 , A 8 , A 9 ) material can be made either of recycled (PVC), virgin (PVC) material or a mixture of both. [0025] The invention as described combines the mechanical locking system that is known to be patented by UNILIN BEHEER BV: European Application number: 10010483.5; Application date: 7 Jun. 1997; Publication number: EP2280131 and FLOORING INDUSTRIES LIMITED, SARL: Publication number: WO/2011/001326; Publication date: 6 Jan. 2011; International application number: PCT/IB 2010/052812; IPC: E04E 15/02 (2006 January) and are hereby noted to facilitate the installation procedure of natural stone core (A 4 ) tile slabs ( 01 ) without the use of cement, adhesives and grout and with polyvinyl chloride couplings (A 6 , A 5 , A 8 , A 9 ) not part of the natural stone core (A 4 ), according to the invention. [0026] The following illustrates the manufacturing process and the manner in which polyvinyl chloride couplings (A 6 ,A 5 ,A 8 ,A 9 ) are inserted into the core (A 4 ) of natural stone tile slabs ( 01 ) and manufactured or altered in an optimum manner. Cutting into the natural stone core material (A 4 ) horizontally will create an opening of 3 mm to 38 mm in depth or thickness and 3 mm to 38 mm in width on the underside of the tile slab ( 01 ) and on all four sides or edges. After openings are completed the polyvinyl chloride couplings (A 6 , A 5 , A 8 , A 9 ) are inserted into said opening and jointed to the core (A 4 ). A backing layer ( 14 ) which covers the entire underside of the tile slab is applied immediately and a predetermined amount of tile slabs are pressed together to insure the couplings, (A 6 , A 5 , A 8 , A 9 ) and the backing layer ( 14 ) are jointed and pressed. After pressing, tile slabs ( 01 ) are ready to be profiled into the shape of the polyvinyl chloride couplings, (A 6 , A 5 , A 8 , A 9 ) according to the FIGS. 1 , 2 , 3 and 4 . [0027] The manufacturing profiling equipment that will shape and profile the mechanical locking system couplings (A 6 , A 5 , A 8 , A 9 ) is similar to the wood flooring industry but with alterations for cutting into the stone core (A 4 ), according to the invention. [0028] The inventor found that the aforementioned materials, in particular polyvinyl chloride, have ideal features in order to realize a connection, when jointed to the core (A 4 ) which has the flexibility needed for milling, thus obtaining a perfect connection with polyvinyl chloride couplings (A 6 ,A 5 ,A 8 ,A 9 ). [0029] Natural stone tile slabs ( 01 ) are provided with a decorative finish ( 8 ) as shown on drawing which can be honed, polished, sawn cut, antiquated, brushed, tumbled, bush hammered with a variety of natural stone patterns, even with a fancy pattern. The protective top layer ( 3 ) consists of a polyurethane layer of resin transparent material with a gloss or matt finish. Said tile slabs ( 01 ) can be of various shape, for example, rectangular or square, or of any other shapes. [0030] An important characteristic of the invention is the backing layer ( 14 ) that is integrated onto the underside of the tile slabs core (A 4 ) made of cork or of syntactic foam material therefore will insulate and provide acoustical and thermal properties and create a comfortable underfoot feeling for natural stone tile slabs ( 01 ). [0031] Referring to FIG. 1 represents a tile slab ( 01 ) consisting of a natural stone core (A 4 ) with mechanical locking system couplings namely (A 6 -A 5 ) made of polyvinyl chloride. Such couplings have a thickness or depth of around 3 mm to 38 mm and around 3 mm to 38 mm of width or length jointed to the core (A 4 ) of one tile slab ( 01 ). Further, shows the surface finish ( 08 ) that can have different finishes such as honed, polished or similar. Further, also shows a protective coating consisting of a polyurethane transparent layer ( 3 ). Further, also shows a resin sealant material ( 15 ) that is applied during the manufacturing process to protect the coupling joints ( 13 ). Further, also shows a micro bevelled edge ( 17 ) on all four sides of tile slab. Further in addition, it shows a backing layer ( 14 ) consisting of cork and a syntactic foam material that is acoustical and thermal and a comfortable underfoot feeling, according to the invention. [0032] Referring to FIG. 2 represents a tile slab ( 01 ) consisting of a natural stone core (A 4 ) with mechanical locking system couplings namely (A 8 -A 9 ) made of polyvinyl chloride, such couplings have a thickness or depth of around 3 mm to 38 mm and around 3 mm to 38 mm of width or length jointed to the core (A 4 ) of one tile slab ( 01 ). Further shows the surface finish ( 08 ) that can have different finishes such as honed, polished or similar. Further, also shows a protective coating consisting of a polyurethane transparent layer ( 3 ). Further also shows a resin sealant material ( 15 ) that is applied during the manufacturing process to protect the coupling joints ( 13 ). Further, also shows a micro bevelled edge ( 17 ) on all four sides of tile slab. Further in addition, it shows a backing layer ( 14 ) consisting of cork and/or a syntactic foam material that is acoustical and thermal and a comfortable underfoot feeling, according to the invention. [0033] Referring to FIG. 3 represents a tile slab ( 01 ) consisting of a natural stone core (A 4 ) with mechanical locking system couplings namely (A 8 -A 9 ), generally the same features as shown in FIG. 2 , but it illustrates the manner in which said couplings (A 8 -A 9 ) connect together by mechanical locking means without the use of cement, adhesives and grout, according to the invention. [0034] Referring to FIG. 4 represents a tile slab ( 01 ) consisting of a natural stone core (A 4 ) with mechanical locking system couplings namely (A 6 -A 5 ), generally the same features as shown in FIG. 1 , but it illustrates the manner in which said couplings (A 6 -A 5 ) connect together by mechanical locking means without the use of cement, adhesives and grout, according to the invention. [0035] To better illustrate the characteristics according to the invention, as an example the following FIGS. 1-4 ) and the related information, describe in more detail the invention.

Floor covering ( 01 ) material, consisting of Natural Stones, i.e. Marble, Granite, Limestone, Onyx, Travertine and Sandstone, in format of tile slabs, in which the thickness is between 4 mm and 35 mm, in which at the two opposite edges or sides are jointed together and interlocked by mechanical locking means, by connecting or inserting (A 6 to A 5 ) and connecting or pressing downward (A 8 to A 9 ) using Polyvinyl Chloride (PVC) couplings, connecting in the form of a tongue and a groove which will prevent shifting of two interlocked tiles and or slabs into the opposed direction of each section tile or slab, with an integrated backing layer consisting of cork and/or syntactic foam material, The invention relates to a natural stone core tile slab, allowing for an installation without the use of cement, adhesives or grout, provided with such a mechanical locking system jointed to the core (A 4 ) according to the invention.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a drive system for a vehicle movable accessory, and especially a drive system for an automotive vehicle outer accessory, such as an antenna, a window glass, or a sun roof. 2. Description of the Prior Art Japanese published unexamined utility model application 57-185205 discloses a control system for a motor driven rod antenna. In this control system, when the load on an antenna drive motor exceeds a certain level, the supply of an electric current to the motor is interrupted. Japanese published unexamined utility model application 57-198104 discloses a drive system for a motor antenna mounted on a vehicle. In this drive system, an antenna drive motor is activated in response to a signal from an associated radio receiver power switch or a signal from a relay corresponding to the radio receiver power switch. The drive motor is deactivated in response to a signal from a switch of another sound device, a signal from a vehicle key switch, or signals from relays corresponding to the switch of the sound device and the key switch. Japanese published examined utility model application 60-42487 discloses a power antenna including a antenna drive motor and limit switches. When an antenna reaches preset positions, these limit switches act to interrupt the electric current supply to the drive motor. This power antenna also includes a timer. In the case of a failure of the limit switches, the timer restricts the duration of the motor current supply to a preset interval. Japanese published unexamined patent application 60-43903 discloses a motor antenna drive system. In this drive system, the position of an antenna is monitored by an angular position sensor associated with the shaft of an antenna drive motor. When the monitored position of the antenna reaches a given position, the drive motor is deactivated. The given position of the antenna can be selected from the longest position, the shortest position, and a position or positions intermediate between the two limit positions. Japanese published unexamined patent application 61-18375 discloses a vehicle power window control system. In this control system, load on a window drive motor is monitored. In cases where the window is being closed, when the monitored motor load exceeds a reference level, the drive motor is stopped and is then reversed to open the window. After that, a device included in this control system inhibits activation of the drive motor in the direction of closing the window. The inhibitory operation of this device is cancelled by rethrowing a vehicular engine ignition switch. SUMMARY OF THE INVENTION It is an object of this invention to provide a drive system for a vehicle movable accessory which enables reliable self-protection against undesirable locking or sticking of the accessory. In a vehicle accessory drive system according to a first aspect of this invention, a rotatable motor is connected to a vehicle accessory to move the accessory. The accessory is movable between a first position and a second position. The motor moves the accessory toward the first position and the second position as the motor rotates in a first direction and a second direction respectively. A first operation signal is generated when the accessory is required to move toward the first position. A second operation signal is generated when the accessory is required to move toward the second position. Load on the motor is sensed. A stop signal is generated when the sensed motor load exceeds a reference level. The motor is stopped when the stop signal is generated. A device serves to rotate the motor in the first direction when the first operation signal is generated. A device serves to rotate the motor in the second direction when the second operation signal is generated. Rotation of the motor in the first direction is inhibited in response to the stop signal generated after generation of the first operation signal. The inhibition of rotation of the motor in the second direction is also cancelled in response to the stop signal. In a vehicle accessory drive system according to a second aspect of this invention, a motor serves to move a vehicle movable accessory. When the accessory is required to move, the motor is activated. Load on the motor is sensed. When the sensed load exceeds a reference level, the motor is deactivated. After the motor is deactivated, a device inhibits activation of the motor which induces movement of the accessory in a direction which is the same as the direction of movement of the accessory during a period prior to the deactivation of the motor. The inhibition of activation of the motor is cancelled when the accessory is required to move in a direction different from the direction of movement of the accessory during the period prior to the deactivation of the motor. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a general block diagram of a vehicle accessory drive system according to an embodiment of this invention. FIG. 2 is a specific block diagram of the vehicle accessory drive system of FIG. 1. FIG. 3 is a diagram illustrating connection between contacts of a key switch of FIGS. 1 and 2 in four different positions. DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of this invention will be described hereinafter. In this embodiment, this invention is applied to a vehicle movable antenna. It should be noted that the invention is not limited to this embodiment and can be applied to other vehicle movable accessories such as a window and a sun roof. With reference to FIG. 1, a key switch 10, a cassette switch 20, and a radio receiver switch 30 are connected in series. The key switch 10 is connected to an electric dc power source B such as a battery. The cassette switch 20 is actuated when a cassette tape is inserted into and removed from a cassette tape reproducing device or tape deck. The radio receiver switch 30 is connected to a radio receiver (not shown). The radio receiver is normally turned on and off in accordance with movement of the radio receiver switch 30. When the radio receiver switch 30 is actuated to turn on the radio receiver, the radio receiver switch 30 normally serves to generate an antenna extending signal. When the radio receiver switch 30 is actuated to turn off the radio receiver, the radio receiver switch 30 normally serves to generate an antenna shortening signal. An up control circuit 40 is connected to the radio receiver switch 30 and a motor drive circuit 90. The motor drive circuit 90 is connected to an antenna drive motor M. The motor M is mechanically connected to an extensible or retractable radio receiver rod antenna described hereinafter. When the up control circuit 40 receives an antenna extending signal from the radio receiver switch 30, the circuit 40 outputs a normal rotation signal to the motor drive circuit 90, thereby rotating the motor M in its normal direction and extending the antenna. The up control circuit 40 outputs the normal rotation signal unless a stop signal, described hereinafter, is given. A stop detection circuit 80 is connected to the up control circuit 40. The stop detection circuit 80 electrically monitors the load on the motor M. When the monitored motor load exceeds a reference level, the stop detection circuit 80 outputs a motor stop signal. An up inhibition circuit 50 is connected to the radio receiver switch 30, the up control circuit 40, and the stop detection circuit 80. The up inhibition circuit 50 outputs a normal rotation inhibition signal to the up control circuit 40 in response to the stop signal from the stop detection circuit 80. The normal rotation inhibition signal is designed to prevent normal rotation of the motor M. The up inhibition circuit 50 holds the normal rotation inhibition signal until the previously-mentioned antenna shortening signal occurs. When the antenna shortening signal is outputted to the up inhibition circuit 50, the circuit 50 turns off the normal rotation inhibition signal. A down control circuit 60 is connected to the radio receiver switch 30 and the motor drive circuit 90. When the down control circuit 60 receives an antenna shortening signal from the radio receiver switch 30, the circuit 60 outputs a reverse rotation signal to the motor drive circuit 90, thereby rotating the motor M in its reverse direction and shortening the antenna. The down control circuit 60 outputs the reverse rotation signal unless a stop signal outputted by the stop detection circuit 80 is given. A down inhibition circuit 70 is connected to the radio receiver switch 30, the down control circuit 60, and the stop detection circuit 80. The down inhibition circuit 70 outputs a reverse rotation inhibition signal to the down control circuit 60 in response to the stop signal from the stop detection circuit 80. The reverse rotation inhibition signal is designed to prevent reverse rotation of the motor M. The down inhibition circuit 70 holds the reverse rotation inhibition signal until the previously-mentioned antenna extending signal occurs. When the antenna extending signal is outputted to the down inhibition circuit 70, the circuit 70 turns off the reverse rotation inhibition signal absent. As shown in FIG. 2, the circuits 40, 50, 60, 70, 80, and 90 are continuously powered by the battery B independent of the states of the switches 10, 20, and 30. The key switch 10 includes a movable contact +B and fixed contacts 10a, 10b, 10c, 10d, and 10e. The movable contact +B is connected to the positive terminal of the battery B. The fixed contact 10a is connected to a vehicular engine starting device (not shown). The fixed contacts 10b and 10c are connected to a vehicular engine ignition device (not shown). The fixed contact 10d is connected to vehicle accessories and a movable contact 20c of the cassette switch 20. The fixed contact 10e is generally isolated. As shown in FIG. 3, the key switch 10 is movable among an OFF position, an ACC position, an IG position, and an ST position. When the key switch 10 assumes the OFF position, the movable contact +B moves into connection with only the fixed contact 10e. When the key switch 10 assumes the ACC position, the movable contact +B moves into connection with only the fixed contact 10d, applying the voltage of the battery B to the vehicle accessories and the cassette switch 20. When the key switch 10 assumes the IG position, the movable contact +B moves into connnection with the fixed contacts 10b and 10c, applying the battery voltage to the engine ignition device, the vehicle accessories, and the cassette switch 20. When the key switch 10 assumes the ST position, the movable contact +B moves into connection with the fixed contacts 10a and 10b, applying the battery voltage to the engine starting device and the engine ignition device. The cassette switch 20 includes fixed contacts 20a and 20b, and a movable contact 20c. As described previously, the movable contact 20c is connected to the fixed contact 10d of the key switch 10. When a cassette tape is inserted into the associated reproducing device, the movable contact 20c is connected to the fixed contact 20b but is disconnected from the fixed contact 20a. When a cassette tape is removed from the associated reproducing device, the movable contact 20c is connected to the fixed contact 20a but is disconnected from the fixed contact 20b. The fixed contact 20a is connected to the radio receiver switch 30. The fixed contact 20b is connected to the down control circuit 60 via a diode 122. Provided that the key switch 10 is in the ACC position or the IG position, the radio receiver is turned on and off when the radio receiver switch 30 is closed and opened respectively. The radio receiver switch 30 is connected to the up control circuit 40 and the down inhibition circuit 70. The radio receiver switch 30 is also connected to the down control circuit 60 via a diode 121. A main circuit 100 controlling the motor drive circuit 90 includes the up control circuit 40, the up inhibition circuit 50, the down control circuit 60, and the down inhibition circuit 70. As described previously, the shaft of the motor M is mechanically connected to an extensible or retractable radio receiver rod antenna 110 via a known gear arrangement or drive train. When the shaft of the motor M rotates in a first direction and in a second direction, the antenna 110 is extended and shortened respectively. The up control circuit 40 includes an OR gate 41, a differentiating circuit 42, a one-shot multivibrator 43, a flip-flop (FF) 44, and an AND gate 45. A first input terminal of the OR gate 41 is connected to the radio receiver switch 30. A second input terminal of the OR gate 41 is connected to an output terminal of an AND gate 54 within the up inhibition circuit 50. An output terminal of the OR gate 41 is connected to an input terminal of the differentiating circuit 42. The differentiating circuit 42 detects a rising edge of an output signal from the OR gate 41. An output terminal of the differentiating circuit 42 is connected to an input terminal of the one-shot multivibrator 43. The one-shot multivibrator 43 wave-shapes an output signal from the differentiating circuit 42 and outputs a set pulse having a fixed duration. An output terminal of the one-shot multivibrator 43 is connected to a set terminal of the flip-flop 44. A reset terminal of the flip-flop 44 is connected to the stop detection circuit 80 via an inverter 124. In the flip-flop 44, set operation takes precedence over reset operation. When the set terminal of the flip-flop 44 receives a high level signal from the one-shot multivibrator 43, the flip-flop 44 is set and generates a high level signal via its Q output terminal. When the reset terminal of the flip-flop 44 receives a stop signal from the stop detection circuit 80, the flip-flop 44 is reset and generates a low level signal via its Q output terminal. The Q output terminal of the flip-flop 44 is connected to a first input terminal of the AND gate 45. A second input terminal of the AND gate 45 is connected to the radio receiver switch 30. An output terminal of the AND gate is connected to the motor drive circuit 90. The up inhibition circuit 50 includes a flip-flop 51, an AND gate 52, a flip-flop 53, and an AND gate 54. A set terminal of the flip-flop 51 is connected to the output terminal of the one-shot multivibrator 43 within the up control circuit 40. In the flip-flop 51, set operation takes precedence over reset operation. A first input terminal of the AND gate 52 is connected to the Q output terminal of the flip-flop 44 within the up control circuit 40. A second input terminal of the AND gate 52 is connected to the stop detection circuit 80 via the inverter 124. A set terminal of the flip-flop 53 is connected to an output terminal of the AND gate 52. In the flip-flop 53, set operation takes precedence over reset operation. A first input terminal of the AND gate 54 is connected to a Q output terminal of the flip-flop 53. A second input terminal of the AND gate 54 is connected to a Q output terminal of the flip-flop 51. As described previously, an output terminal of the AND gate 54 is connected to the OR gate 41 within the up control circuit 40. When the set terminal of the flip-flop 51 receives a high level signal from the one-shot multivibrator 43 within the up control circuit 40, the flip-flop 51 is set and generates a high level signal via its Q output terminal. When the set terminal of the flip-flop 53 receives a high level signal from the AND gate 52, the flip-flop 53 is set and generates a high level signal via its Q output terminal. The AND gate 52 is caused to output a high level signal by a stop signal from the stop detection circuit 80 and a signal outputted from the Q output terminal of the flip-flop 44 at a moment immediately prior to the moment of resetting of the flip-flop 44 by the stop signal. The AND gate 54 outputs a high level signal as a motor normal rotation inhibition signal when both of the flip-flops 51 and 53 are in their set states. Reset terminals of the flip-flops 51 and 53 are connected to an output terminal of an inverter 67 within the down control circuit 60. When the reset terminals of the flip-flops 51 and 53 receive a high level signal from the inverter 67, the flip-flops 51 and 53 are reset and remove or cancel the motor normal rotation inhibition signal. The down control circuit 60 includes a delay circuit 61, an OR gate 62, a differentiating circuit 63, a one-shot multivibrator 64, a flip-flop 65, an AND gate 66, and the inverter 67. A first input terminal of the OR gate 62 is connected to the radio receiver switch 30 via the diode 121. The first input terminal of the OR gate 62 is also connected to the fixed contact 20b of the cassette switch 20 via the diode 122. A second input terminal of the OR gate 62 is connected to an output terminal of an AND gate 123. An inverting input terminal of the AND gate 123 is connected to the fixed contact 10c of the key switch 10. A non-inverting input terminal of the AND gate 123 is connected to the fixed contacts 10a and 10b. A third input terminal of the OR gate 62 is connected to an output terminal of an AND gate 74 within the down inhibition circuit 70. An input terminal of the delay circuit 61 is connected to an output terminal of the OR gate 62. An input terminal of the differentiating circuit 63 is connected to an output terminal of the delay circuit 61. The differentiating circuit 63 detects a falling edge of an output signal from the delay circuit 61. An input terminal of the one-shot multivibrator 64 is connected to an output terminal of the differentiating circuit 63. The one-shot multivibrator 64 wave-shapes an output signal from the differentiating circuit 63 and outputs a set pulse having a fixed duration. In the flip-flop 65, set operation takes precedence over reset operation. A set terminal of the flip-flop 65 is connected to an output terminal of the one-shot multivibrator 64. A reset terminal of the flip-flop 65 is connected to the stop detection circuit 80 via the inverter 124. A non-inverting input terminal of the AND gate 66 is connected to a Q output terminal of the flip-flop 65. An inverting input terminal of the AND gate 66 is connected to the output terminal of the OR gate 62. An output terminal of the AND gate 66 is connected to the motor drive circuit 90. An input terminal of the inverter 67 is connected to the output terminal of the OR gate 62. The device 67 inverts an output signal from the OR gate 62. When the set terminal of the flip-flop 65 receives a high level signal from the one-shot multivibrator 64, the flip-flop 65 is set and generates a high level signal via its Q output terminal. When the reset terminal of the flip-flop 65 receives a stop signal from the stop detection circuit 80, the flip-flop 65 is reset and generates a low level signal via its Q output terminal. The down inhibition circuit 70 includes a flip-flop 71, an AND gate 72, a flip-flop 73, and an AND gate 74. A set terminal of the flip-flop 71 is connected to the output terminal of the one-shot multivibrator 64 within the down control circuit 60. A reset terminal of the flip-flop 71 is connected to the radio receiver switch 30. In the flip-flop 71, set operation takes precedence over reset operation. When the set terminal of the flip-flop 71 receives a high level signal from the one-shot multivibrator 64, the flip-flop 71 is set and generates a high level signal via its Q output terminal. A first input terminal of the AND gate 72 is connected to the Q output terminal of the flip-flop 65 within the down control circuit 60. A second input terminal of the AND gate 72 is connected to the stop detection circuit 80 via the inverter 124. The AND gate 72 is caused to output a high level signal by a stop signal from the stop detection circuit 80 and a signal outputted from the Q output terminal of the flip-flop 65 at a moment immediately prior to the moment of resetting of the flip-flop 65 by the stop signal. A set terminal of the flip-flop 73 is connected to an output terminal of the AND gate 72. A reset terminal of the flip-flop 73 is connected to the radio receiver switch 30. In the flip-flop 73, set operation takes precedence over reset operation. When the set terminal of the flip-flop 73 receives a high level signal from the AND gate 72, the flip-flop 73 is set and generates a high level signal via its Q output terminal. A first input terminal of the AND gate 74 is connected to the Q output terminal of the flip-flop 71. A second input terminal of the AND gate 74 is connected to the Q output terminal of the flip-flop 73. As described previously, an output terminal of the AND gate 74 is connected to the OR gate 62 within the down control circuit 60. The AND gate 74 outputs a high level signal as a motor reverse rotation inhibition signal when both of the flip-flops 71 and 73 are in their set states. When the reset terminals of the flip-flops 71 and 73 receive a high level signal from the radio receiver switch 30, the flip-flops 71 and 73 are reset and generate respective low level signals via their Q output terminals, removing or cancelling the reverse rotation inhibition signal outputted by the AND gate 74. The motor drive circuit 90 includes a transistor 91, an electromagnetic winding or relay winding 92, a relay switch 93, a transistor 94, an electromagnetic winding or relay winding 95, and a relay switch 96. The base of the transistor 91 is connected to the output terminal of the AND gate 45 within the up control circuit 40. The emitter-collector path of the transistor 91 is connected across the battery B via the relay winding 92. When a high level signal is applied to the base of the transistor 91 from the AND gate 45, the transistor 91 is made conductive so that the relay winding 92 is energized by the battery B. When a low level signal is applied to the base of the transistor 91 from the AND gate 45, the transistor 91 is made non-conductive so that the relay winding 92 is de-energized. The relay switch 93 includes fixed contacts 93a and 93b, and a movable contact 93c. The fixed contact 93a is connected to the positive terminal of the battery B. The fixed contact 93b is connected to the stop detection circuit 80. The movable contact 93c is connected to a first terminal of the motor M. The relay switch 93 is associated with the relay winding 92. When the relay winding 92 is de-energized, the movable contact 93c is connected to the fixed contact 93b but is disconnected from the fixed contact 93a. When the relay winding 92 is energized, the movable contact 93c is connected to the fixed contact 93a but is disconnected from the fixed contact 93b so that an electric current produced by the battery B is generally allowed to flow through the motor M to rotate the motor M in its normal direction. The base of the transistor 94 is connected to the output terminal of the AND gate 66 within the down control circuit 60. The emitter-collector path of the transistor 94 is connected across the battery B via the relay winding 95. When a high level signal is applied to the base of the transistor 94 from the AND gate 66, the transistor 94 is made conductive so that the relay winding 95 is energized by the battery B. When a low level signal is applied to the base of the transist or 94 from the AND gate 66, the transistor 94 is made non-conductive so that the relay winding 95 is de-energized. The relay switch 96 includes fixed contacts 96a and 96b, and a movable contact 96c. The fixed contact 96a is connected to the positive terminal of the battery B. The fixed contact 96b is connected to the stop detection circuit 80. The movable contact 96c is connected to a second terminal of the motor M. The relay switch 96 is associated with the relay winding 95. When the relay winding 95 is de-energized, the movable contact 96c is connected to the fixed contact 96b but is disconnected from the fixed contact 96a. When the relay winding 95 is energized, the movable contact 96c is connected to the fixed contact 96a but is disconnected from the fixed contact 96b so that an electric current produced by the battery B is generally allowed to flow through the motor M to rotate the motor M in its reverse direction. The stop detection circuit 80 includes resistors 81, 82, 83, and 84, a comparator 85, a resistor 86, and a capacitor 87. A first end of the resistor 81 is connected to the fixed contacts 93b and 96b of the relay switches 93 and 96 within the motor drive circuit 90. The first end of the resistor 81 is also connected to a first input terminal of the comparator 85 via the resistor 86. A second end of the resistor 81 is connected to the negative terminal of the battery B via the ground. The resistor 81 senses load on the motor M. Specifically, an electric current flowing through the motor M passes through the resistor 81 so that the voltage across the resistor 81 represents the current flowing through the motor M. Since the current flowing through the motor M reflects the load on the motor M, the voltage across the resistor 81 represents the load on the motor M. The voltage across the resistor 81 will be called a motor load voltage hereinafter. The motor load voltage is applied to the first input terminal of the comparator 85. The resistors 82 and 83 are connected in series. The series combination of the resistors 82 and 83 is connected across the battery B. The junction between the resistors 82 and 83 is connected to a second input terminal of the comparator 85. The series combination of the resistors 82 and 83 divides the constant battery voltage and derives a reference constant voltage induced across the resistor 83. The reference constant voltage is applied to the second input terminal of the comparator 85. The reference constant voltage corresponds to a reference load on the motor M. When the motor load voltage is equal to or higher than the reference voltage, that is, when load on the motor M is equal to or greater than the reference load, the comparator 85 outputs a low level signal. When the motor load voltage is lower than the reference voltage, that is, when load on the motor M is smaller than the reference load, the comparator 85 outputs a high level signal. An output terminal of the comparator 85 is connected to an input terminal of the inverter 124. An output terminal of the inverter 124 is connected to the flip-flop 44 within the up control circuit 40, the AND gate 52 within the up inhibition circuit 50, the flip-flop 65 within the down control circuit 60, and the AND gate 72 within the down inhibition circuit 70. The comparator 85 is connected to the battery B so that the comparator 85 is powered by the battery B. The output terminal of the comparator 85 is connected to the positive terminal of the battery B via the resistor 84. Opposite ends of the capacitor 87 are connected to the first and second input terminals of the comparator 85 respectively. During activation of the motor M, when the antenna 110 sticks or becomes locked due to some causes, the load on the motor M generally increases above the reference load so that the comparator 85 outputs a low level signal. This low level signal is converted by the inverter 124 into a high level stop signal. During activation of the motor M, when the antenna 110 is moving normally, the load on the motor M remains below the reference load so that the comparator 85 outputs a high level signal and thus a stop signal is absent. When the key switch 10 is changed from the IG position to the ST position, the AND gate 123 outputs a high level signal to the down control circuit 60, thereby preventing the antenna 110 from being shortened. The high level signal outputted from the AND gate 123 to the down control circuit 60 also prevents the inhibition of antenna extending operation from being cancelled. The vehicle accessory drive system of FIGS. 1-3 operates as follows. [Up Operation] In cases where the key switch 10 is in the ACC position or the IG position and where a cassette tape is removed from the cassete tape reproducing device so that the cassette switch movable contact 20c is connected to the cassette switch fixed contact 20a, when the radio receiver switch 30 is closed to turn on the radio receiver, an antenna extending signal consisting of a change from a low level to a high level is outputted via the radio receiver switch 30. In the up control circuit 40, an output signal of the OR gate 41 changes from a low level to a high level in response to the antenna extending signal, so that the differentiating circuit 42 outputs a pulse. This pulse from the differentiating circuit 42 is converted into a fixed duration pulse by the one-shot multivibrator 43. The fixed duration pulse from the one-shot multivibrator 43 sets the flip-flop 44 and the flip-flop 51 within the up inhibition circuit 50, so that high level signals are generated at the Q output terminals of these flip-flops 44 and 51. The high level signal from the flip-flop 44 allows the AND gate 45 to output a high level signal as a normal rotation signal, which makes the transistor 91 conductive. When the transistor 91 is made conductive, the relay winding 92 is energized so that the relay switch movable contact 93c is connected to the relay switch fixed contact 93a. The connection of the movable contact 93c to the fixed contact 93a allows the battery B to supply a normally directed electric current to the motor M, thereby rotating the motor M in its normal direction and extending the antenna 110. [Suspension of Up Operation] In cases where the motor M is rotated in its normal direction, when the antenna 110 is fully extended so that the motor M is locked, or when the antenna 110 sticks or becomes locked due to freezing or the like so that the motor M is locked, load on the motor M increases and thus the stop detection circuit 80 allows the inverter 124 to output a high level stop signal. This stop signal is applied to the reset terminal of the flip-flop 44, so that the flip-flop 44 is reset and the potential at the Q output terminal of the flip-flop 44 goes low. When the output signal from the flip-flop 44 goes low, the AND gate 45 is closed and thus the normal rotation signal from the AND gate 45 is made absent. As a result, the transistor 91 is made non-conductive and the relay winding 92 is de-energized. The de-energization of the relay winding 92 disconnects the relay switch movable contact 93c from the relay switch fixed contact 93a, thereby interrupting the electric current supply to the motor M and suspending the normal rotation of the motor M. Immediately before the potential at the Q output terminal of the flip-flop 44 changes to a low level which causes the suspension of the normal rotation of the motor M, the stop signal outputted by the inverter 124 and the high level signal generated at the Q output terminal of the flip-flop 44 allow the AND gate 52 to output a pulse signal. The pulse signal from the AND gate 52 sets the flip-flop 53 so that a high level signal is generated at the Q output terminal of the flip-flop 53. Accordingly, the AND gate 54 receives the high level signals from the flip-flops 51 and 53, outputting a high level signal to the OR gate 41 as a normal rotation inhibition signal. The normal rotation inhibition signal lasts until the flip-flops 51 and 53 are reset. During the presence of the normal rotation inhibition signal, even when an antenna extending high level signal is outputted via the radio receiver switch 30 again, the differentiating circuit 42 does not respond to the antenna extending signal so that the supply of a normally directed electric current to the motor M is prevented. Thus, in the case where the motor M is locked during or after the normal rotation, the supply of a normally directed electric current to the motor M is inhibited after the locking of the motor M. For example, an antenna extending high level signal is outputted again by rethrowing the key switch 10 while holding the radio receiver switch 30 closed. Also, an antenna extending high level signal is outputted again by actuating the cassette switch 20 while holding the radio receiver switch 30 closed. [Down Operation] In cases where the key switch 10 is in the ACC position or the IG position and where a cassette tape is removed from the cassette tape reproducing device so that the cassette switch movable contact 20c is connected to the cassette switch fixed contact 20a, when the radio receiver switch 30 is opened to turn off the radio receiver, an antenna shortening signal consisting of a change from a high level to a low level is outputted via the radio receiver switch 30. In the down control circuit 60, an output signal of the OR gate 62 changes from a high level to a low level in response to the antenna shortening signal. This change in the output signal from the OR gate 62 is transmitted to the differentiating circuit 63 via the delay circuit 61, so that the differentiating circuit 63 outputs a pulse. This pulse from the differentiating circuit 63 is converted into a fixed duration pulse by the one-shot multivibrator 64. The fixed duration pulse from the one-shot multivibrator 64 sets the flip-flop 65 and the flip-flop 71 within the down inhibition circuit 70, so that high level signals are generated at the Q output terminals of these flip-flops 65 and 71. The high level signal from the flip-flop 65 allows the AND gate 66 to output a high level signal as a reverse rotation signal, which makes the transistor 94 conductive. When the transistor 94 is made conductive, the relay winding 95 is energized so that the relay switch movable contact 96c is connected to the relay switch fixed contact 96a. The connection of the movable contact 96c to the fixed contact 96a allows the battery B to supply a reversely directed electric current to the motor M, thereby rotating the motor M in its reverse direction and shortening the antenna 110. The antenna shortening signal is also transmitted to the reset terminals of the flip-flops 51 and 53 within the up inhibition circuit 50 via the OR gate 62 and the inverter 67, so that the flip-flops 51 and 53 are reset. When the flip-flops 51 and 53 are reset, the normal rotation inhibition signal outputted by the AND gate 54 is cancelled or removed. [Suspension of Down Operation] In cases where the motor M is rotated in its reverse direction, when the antenna 110 is fully shortened or retracted so that the motor M is locked, or when the antenna 110 sticks or becomes locked due to freezing or the like so that the motor M is locked, load on the motor M increases and thus the stop detection circuit 80 allows the inverter 124 to output a high level stop signal. This stop signal is applied to the reset terminal of the flip-flop 65, so that the flip-flop 65 is reset and the potential at the Q output terminal of the flip-flop 65 goes low. When the output signal from the flip-flop 65 goes low, the AND gate 66 is closed and thus the reverse rotation signal from the AND gate 66 is removed. As a result, the transistor 94 is made non-conductive and the relay winding 95 is de-energized. The de-energization of the relay winding 95 disconnects the relay switch movable contact 96c from the relay switch fixed contact 96a, thereby interrupting the electric current supply to the motor M and suspending the reverse rotation of the motor M. Immediately before the potential at the Q output terminal of the flip-flop 65 changes to a low level which causes the suspension of the reverse rotation of the motor M, the stop signal outputted by the inverter 124 and the high level signal generated at the Q output terminal of the flip-flop 65 allow the AND gate 72 to output a pulse signal. The pulse signal from the AND gate 72 sets the flip-flop 73 so that a high level signal is generated at the Q output terminal of the flip-flop 73. Accordingly, the AND gate 74 receives the high level signals from the flip-flops 71 and 73, outputting a high level signal to the OR gate 62 as a reverse rotation inhibition signal. The reverse rotation inhibition signal lasts until the flip-flops 71 and 73 are reset. During the presence of the reverse rotation inhibition signal, even when an antenna shortening signal is outputted again, the differentiating circuit 63 does not respond to the antenna shortening signal so that the supply of a reversely directed electric current to the motor M is prevented. Thus, in the case where the motor M is locked during or after the reverse rotation, the supply of a reversely directed electric current to the motor M is inhibited after the locking of the motor M. The flip-flops 71 and 73 within the down inhibition circuit 70 are reset by a subsequent antenna extending signal outputted via the radio receiver switch 30. When the flip-flops 71 and 73 are reset, the reverse rotation inhibition signal outputted by the AND gate 74 is cancelled or removed. In the case where the reverse inhibition signal is absent, when the key switch 10 is moved to the OFF position, the down control circuit 60 and the motor drive circuit 90 allow a reversely directed electric current to flow through the motor M independent of the states of the cassette switch 20 and the radio receiver switch 30. This supply of the reversely directed current to the motor M continues until the antenna 110 is fully shortened or retracted. As described previously, in cases where the antenna 110 is being extended or shortened, when the antenna 110 sticks or becomes locked due to freezing or the like, the activation of the motor M is suspended. Simultanesously, the up inhibition circuit 50 or the down inhibition circuit 70 generates a motor rotation inhibition signal which prevents or forbids the rotation of the motor M in the same direction as the direction of the rotation of the motor M during the period preceding the suspension of the activation of the motor M. This motor rotation inhibition signal lasts until a signal designed to rotate the motor M in the opposite direction is produced. In this way, after the antenna 110 sticks or becomes locked, the motor M is prevented from undergoing an electric current angularly forcing the motor M in the same direction as the direction of the rotation of the motor M during a period preceding the locking of the antenna 110. Accordingly, an abnormal or excessive electric current is prevented from flowing through the relay switches 93 and 96, so that long sevice lives of the switches 93 and 96 can be ensured. To cancel the inhibition of the activation of the motor M, it is necessary to produce a signal designed to rotate the motor M in the direction opposite to the direction of the rotation of the motor M during a period preceding the locking of the antenna 110. Accordingly, in cases where the motor M is rotated in the same direction as the direction of the rotation of the motor M during a period preceding the locking of the antenna 110, the motor M needs to be rotated in the opposite direction before the motor M is rotated in the same direction as the direction of the rotation of the motor M during a period preceding the locking of the antenna 110. This rotation of the motor M in the opposite direction relieves stresses on the antenna 110 and the gear arrangement between the motor M and the antenna 110. Therefore, in cases where the motor M is rotated in the same direction as the direction of the rotation of the motor M during a period preceding the locking of the antenna 110 so that the motor M moves again into the same locked state, the motor M and the gear arrangement between the motor M and the antenna 110 are prevented from undergoing stronger stresses. It should be noted that modifications may be made in the embodiment of FIGS. 1-3. For example, one of the up inhibition circuit 50 and the down inhibition circuit 70 may be omitted from the embodiment of FIGS. 1-3. In addition, a motor rotation inhibition signal outputted by the up inhibition circuit 50 or the down inhibition circuit 70 may be automatically removed or cancelled at a moment following the occurrence of the inhibition signal by a preset time interval determined by a device such as a timer.

A motor serves to move a vehicle movable accessory. When the accessory is required to move, the motor is activated. Load on the motor is sensed. When the sensed load exceeds a reference level, the motor is deactivated. After the motor is deactivated, a device inhibits activation of the motor which induces movement of the accessory in a direction same as a direction of movement of the accessory during a period preceding the deactivation of the motor. The inhibition of activation of the motor is cancelled when the accessory is required to move in a direction different from a direction of movement of the accessory during a period preceding the deactivation of the motor.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. Some embodiments are related in general to equipment for servicing subterranean wells, and in some cases, relate to a cementing head that is intended to drop a combination of darts, balls, bombs or canisters in order to activate downhole equipment, launch cementing plugs, deliver chemical products, or the like. Tools currently available on the market for downhole services implement a modular design with darts that are preloaded in baskets within the modules. The modules are connected to one another using clamps. The darts are held in place mechanically and released by removing the mechanical obstruction and redirecting the flow of the pumped fluid (hereinafter called “process fluid”) through the dart basket. The darts are then forced through the tool by the fluid. The first dart to be launched is placed in the lowest module, with subsequent darts passing through the baskets vacated by the earlier darts. Darts in prior art designs are launched by blocking the bypass flow of the process fluid and forcing the fluid through the dart chamber. The dart forms an initial seal when placed into the basket. When fluid enters the dart chamber, pressure builds and breaks the seal, forcing the dart out of the basket, through the tool and into the main process-fluid stream. Some prior art designs consist of modules such as those described in U.S. Pat. Nos. 4,624,312 and 5,890,537 and UK Patent Application GB 2404210A, incorporated in their entirety by reference thereto. The darts are loaded from the topmost module, through the swivel if necessary, and pushed down to their respective baskets with a long rod. The modules have valves that are used to select between the dart and the bypass flow. The valve itself serves as the mechanical obstruction that prevents the dart from prematurely launching. When the valve is turned, it simultaneously opens a passage for the dart while closing the passage of the bypass flow. Current valves are manufactured as a single part. Should the valve malfunction or require servicing, the entire cementing head must be returned to a central facility or district for maintenance. Such an occurrence is inconvenient and costly, particularly if the well site is in a remote location, far from the central facility or district. Despite the valuable contributions of the prior art, it therefore remains desirable to provide an improved valve system that can be maintained at the wellsite if necessary. SUMMARY The embodiments solve at least some of the problems mentioned herein. In an aspect, embodiments relate to an activation-device launching system. In another aspect, embodiments relate to a method for deploying one or more activation devices into a process-fluid stream. In yet another aspect, embodiments relate to a method for cementing a subterranean well. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of an embodiment of the disclosed valve apparatus. DETAILED DESCRIPTION In a first aspect, embodiments relate to an activation-device launching system for a cementing head. As apparent from FIG. 1 , the cementing head comprises a launcher body 1 that comprises a launching chamber 2 and a valve apparatus through which process fluid(s) and activation devices may pass. Activation devices include (but are not limited to) darts, balls, canisters and bombs. The valve apparatus, according to the present invention, is modular, comprising at least two detachable parts. This arrangement allows the operator to remove and disassemble the valve apparatus directly at the wellsite. Thus, repairs and maintenance may be performed at the wellsite and the valve apparatus may be reassembled and reinstalled in the launcher body, obviating the need to transport the equipment to a central facility. To ensure proper reassembly, the valve parts are preferably keyed. In the context of this invention, keying is the placement of protrusions, indentations or both, on the valve parts, giving them shapes that allow valve-apparatus reassembly in only a single correct orientation. One embodiment of the launching system, shown in FIG. 1 , comprises a detachable three-module valve apparatus. The modules comprise a motor connected to a shaft 3 , a valve 4 and a backup shaft 5 . A first key 6 on the valve allows the motor and shaft to only be connected to the first side 7 of the valve, and a second key 8 on the valve allows the backup shaft to only be connected to the second side 9 of the valve. The backup shaft may be operated either manually or hydraulically, and is present for use in case the motor malfunctions. Although the disclosed valve apparatus is mainly being presented in the context of well cementing, it will be appreciated that the process-fluid stream may comprise one or more well fluids including, but not limited to, drilling fluids, cement slurries, spacer fluids, chemical washes, acidizing fluids, gravel-packing fluids and scale-removal fluids. In another aspect, embodiments relate to a method for deploying one or more activation devices into a process-fluid stream, using the inventive activation-device launching system described earlier. A valve apparatus is assembled that comprises at least two detachable modules, wherein the shape of at least one module prevents incorrect valve-apparatus assembly. The valve apparatus is installed in a launching chamber, thereby producing an activation-device launching system. One or more activation devices may be inserted into the launching chamber. Process fluid may be pumped through the activation-device launching system, and the valve may be adjusted such that at least one activation device may be launched into the process-fluid stream. Activation devices may include (but are not limited to) darts, balls, canisters and bombs. One embodiment of the method may employ a valve apparatus comprising three detachable modules: a motor and shaft 3 , a valve 4 and a backup shaft 5 . The valve-apparatus modules are preferably installed in the launcher body 1 by (a) connecting the motor and shaft 3 to the first side 7 of the valve via the first key 6 , (b) inserting the combined motor and shaft and valve into the launcher body, (c) inserting the backup shaft 5 into the other side of the launcher body, and (d) connecting the backup shaft to the second side 9 of the valve via the second key 8 . The backup shaft may be operated either manually or hydraulically, and is present for use in case the motor malfunctions. One or more activation devices may be inserted into the launching chamber 2 , the valve 4 may be set in the main-flow position, and process fluid may be pumped through a main-flow portion of the launcher body 10 . When it is time to launch one or more activation devices, the valve may be set in the bypass-flow position, whereupon one or more activation devices pass through the valve 4 and enter the process-fluid stream via a bypass-flow tube 11 . Although the disclosed method is mainly being presented in the context of well cementing, it will be appreciated that the process-fluid stream may comprise one or more well fluids including, but not limited to, drilling fluids, cement slurries, spacer fluids, chemical washes, acidizing fluids, gravel-packing fluids and scale-removal fluids. In yet another aspect, embodiments relate to a method for cementing a subterranean well, using the inventive activation-device launching system described earlier. A valve apparatus is assembled that comprises at least two detachable modules, wherein the shape of at least one module prevents incorrect valve-apparatus assembly. The valve apparatus is installed in a launching chamber, thereby producing an activation-device launching system. One or more activation devices may be inserted into the launching chamber. Cement slurry may be pumped through the activation-device launching system, and the valve may be adjusted such that at least one activation device may be launched. The cement slurry and one or more activation devices are pumped into the well. Activation devices may include (but are not limited to) darts, balls, canisters and bombs. One embodiment of the method employs a valve apparatus comprising three modules: a motor and shaft 3 , a valve 4 and a backup shaft 5 . The method comprises the following steps. The valve-apparatus modules may be installed in the launcher body 1 by (a) connecting the motor and shaft 3 to the first side 7 of the valve via the first key 6 , (b) inserting the combined motor and shaft and valve into the launcher body, (c) inserting the backup shaft 5 into the other side of the launcher body, and (d) connecting the backup shaft to the second side 9 of the valve via the second key 8 . The backup shaft may be operated either manually or hydraulically, and is present or use in case the motor malfunctions. One or more activation devices may be inserted into the launching chamber 2 , the valve 4 may be set in the main-flow position, and cement slurry may be pumped through a main-flow portion of the launcher body 10 . When it is time to launch one or more activation devices, the valve may be set in the bypass-flow position, whereupon one or more activation devices pass through the valve 4 and enter the cement-slurry stream via a bypass-flow tube 11 . For all aspects of the invention, the activation devices may be filled with a chemical substance that, upon release from the launching chamber, is dispensed from the activation device into the process fluid. The chemical release may occur at any time after the activation device is launched—from the moment of launching to any time thereafter. Delayed chemical release may be performed for a number of reasons including, but not limited to, avoiding fluid rheological problems that the chemical would cause if added during initial fluid mixing at surface, and triggering the initiation of chemical reactions in the fluid (e.g., cement-slurry setting and fracturing-fluid crosslinking) at strategic locations in the well. The preceding description has been presented with reference to some embodiments of the invention. Persons skilled in the art and technology to which this invention pertains will appreciate that alterations and changes in the described structures and methods of operation can be practiced without meaningfully departing from the principle, and scope of this invention. Accordingly, the foregoing description should not be read as pertaining only to the precise structures described and shown in the accompanying drawings, but rather should be read as consistent with and as support for the following claims, which are to have their fullest and fairest scope.

The present invention relates in general to equipment for servicing subterranean wells and in particular to a cementing head that is intended to drop a combination of darts, balls, bombs and canisters in order to activate downhole equipment, launch cementing plugs, deliver chemical products, or the like. A cementing head comprises a modular valve apparatus, comprising at least two detatchable parts. This arrangement allows the operator to remove and disassemble the valve apparatus at the wellsite. Thus, repairs and maintenance may be performed at the wellsite and the valve apparatus may be reassembled and reinstalled, obviating the need to transport the equipment to a central facility.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates in general to supporting a casing in a wellhead, and in particular to a system for supporting the casing under an emergency basis when the casing is stuck. 2. Description of the Prior Art Wellheads of the type concerned herein have a wellhead housing at the top of the well. After drilling the well to the desired depth, a string of casing is lowered into the well. A casing hanger secured to the upper end of the casing lands on a landing shoulder in the wellhead. Cement is pumped down the casing to flow up the annulus around the casing to cement it in place. The well may be subsequently drilled deeper or completed with tubing. Occasionally, an emergency condition will exist. This occurs when the casing becomes stuck in that it cannot move downward or upward. A standard casing hanger secures by threads to the upper end of the casing, and cannot be employed in its normal manner because it would be above the landing shoulder in the wellhead housing. There are various methods and devices used in this situation. Typically they involve cementing the casing, then cutting the casing off in the wellhead housing. Then the operator inserts slips over the casing and sets them on the landing shoulder in the wellhead housing. The operator tensions the casing. Then, a seal or packoff is placed between the wellhead housing and the exterior of the casing. One disadvantage of the prior art method is that it may result in the blowout preventer being inoperative before the casing hanger seal is installed. The blowout preventer mounts above the wellhead housing and seals to the exterior of the casing. Normally the operator must cut off the casing within the wellhead, requiring removal of the blowout preventer. A danger exists that a blowout could occur. It has not been possible to place the slips over the casing prior to cutting the casing because of the existence of a casing collar above the landing shoulder in the wellhead housing. The casing collar is of a larger diameter than the inner diameter of the slip assemblies utilized previously. Also, when sealing, the seals need to seal on the rough exterior of the casing. If metal-to-metal seals are employed, this is very difficult. Metal seals seal best against very smooth surfaces. SUMMARY OF THE INVENTION In this invention, the slip assembly may be installed before the casing is cut. The slip assembly has an expansible bowl and slips in its interior. A running tool will expand the bowl radially as it is being lowered. This enables the slip bowl to be lowered past the casing collar and into the wellhead. Once past the casing collar, the running tool is actuated to allow the bowl to contract. Once in place, the running tool is removed. The slips slide inward to a gripping position to support the casing. A honing tool may be lowered over the casing and placed on top of the slip bowl. The honing tool has a plurality of honing stones. A resilient member urges the honing stones inward. The operator rotates the honing tool to smooth the surface of the casing above the slip bowl. Then, a seal may be set and the casing cut. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a quarter sectional view illustrating a slip assembly and running tool being lowered past a casing collar. FIG. 2 is an enlarged quarter sectional view of the slip assembly of FIG. 1. FIG. 3 is a perspective view of the slip assembly of FIG. 1. FIG. 4 is a half sectional view illustrating a honing tool constructed in accordance with this invention shown placed on the slip assembly of FIG. 1. FIG. 5 is a perspective view, partially broken away, of portions of the honing tool of FIG. 4. DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 2, the well has a wellhead housing 11 which is a large tubular member. Wellhead housing 11 has an axial bore 13. A landing shoulder 15 locates inside bore 13, and faces upward and outward. During drilling, a blowout preventer (not shown) will be mounted above the wellhead housing 11. Referring to FIG. 1, a string of casing 17 extends through the blowout preventer and wellhead housing 11 into the well. The string of casing 17 is made up of sections of casing, each about 40 feet long, each having a threaded end 19 on one end and a casing collar 21 on the opposite end. In FIG. 1, the casing 17 is shown to be stuck in a position in which it will not proceed downward or upward. This results in a collar 21 being located above the landing shoulder 15 and possibly below the blowout preventer. The slip assembly of this invention includes a slip bowl 23. Slip bowl 23 is a tubular member having an upper rim 25 and an external downward facing landing shoulder 27. Landing shoulder 27, as illustrated in FIG. 2, is conical and at the same angle as wellhead housing landing shoulder 15 for landing on wellhead housing landing shoulder 15. A plurality of conical surfaces 29 are formed in the interior of slip bowl 23. As shown in FIG. 3, slip bowl 23 contains expansion means for allowing slip bowl 23 to expand to clear collar 21, then contract after clearing collar 21. The expansion means comprises a plurality of lower and upper slots 31, 33. Slots 31, 33 form a serpentine body for the slip bowl 23. Lower slots 31 extend through the lower rim 34 and terminate a selected distance below the upper rim 25. Upper slots 33 extend through the upper rim 25 and terminate a selected distance above the lower rim 34. Slots 31 and 33 alternate with each other. This results in a continuous body that can be expanded resiliently, and allowed to contract. When in a relaxed position, the inner diameter of slip bowl 23 at its minimum point will be less than the outer diameter of casing collar 21. When expanded to a maximum position, the inner diameter of slip bowl 23 at its minimum will be greater than the outer diameter of casing collar 21. Slip bowl 23 also has a plurality of elongated apertures 35 that extend through its wall and are spaced circumferentially around slip bowl 23. Referring to FIGS. 2 and 3, a set of slips 37 are carried inside slip bowl 23. Each of the slips 37 has a back or exterior with conical surfaces 39 that mate with the slip bowl conical surfaces 23. Each of the slips 37 has an interior face with rows of grooves or teeth 41 for gripping the exterior of casing 17. The slips 37 are separated from each other by clearances 42 (FIG. 3). The slips 37 will move from a retracted position inward to a gripping position shown in FIG. 2. When moving inward, the slips 37 slide downward by gravity on the slip bowl conical surfaces 39. A screw 43 locates in aperture 35 for retaining the slips 37 in the slip bowl 23. Screw 43 will slide in the elongated aperture 35 to allow the slips 37 to move inward and downward from the retracted position. When moving to the gripping position, the clearances 42 will decrease in width, with the slips 37 moving closer to each other. Referring to FIG. 1, a running tool 45 runs the slip bowl 23 and slips 37. Running tool 45 is a tubular member having an outer sleeve 47 and an inner sleeve 49. Inner sleeve 49 is cylindrical and has a plurality of spaced apart fingers 50 depending downward. Each finger 50 will located in one of the clearances 42 between each of the slips 37. Each of the slips 37 locates in a slot (not shown) between each finger 50. When inserted in slip bowl 23, the fingers 50 extend from the upper rim 25 to the lowermost conical surface 29. When inserted, the fingers 50 hold the slips 37 in a spaced apart retracted position, preventing the slips 37 from moving downward and inward to the gripping position. The outer diameter of the inner sleeve 49, measured around fingers 50, is greater than the inner diameter of the slip bowl 23 when slip bowl 23 is in a relaxed position. Consequently, when inserted, the fingers 50 will expand the diameter of the slip bowl 23. Also, the inner diameter of the inner sleeve 49 and fingers 50 is greater than the outer diameter of collar 21. When inserted, the inner diameter of slip bowl 23 directly below the fingers 50 will be substantially the same inner diameter as fingers 50. This enables the running tool 45 with the slip bowl 23 and slips 37 to be inserted over the collar 21. The inner sleeve 49 and fingers 50 will move up and down relative to the outer sleeve 47. Inner sleeve 49 has an annular band or piston 51 on its exterior. Piston 51 has a seal that seals to the interior of outer sleeve 47. A shoulder 53 faces upward on the interior of outer sleeve 47. A space between piston 51 and shoulder 53 defines a chamber 55. A passage 57 connects chamber 55 to a source of hydraulic liquid under pressure. Applying hydraulic pressure to chamber 55 will cause the inner sleeve 49 to move upward relative to the outer sleeve 47. In operation, if the casing string 17 becomes stuck, the operator will cement the casing in place. Before the cement sets completely, the operator will assemble running tool 45 with the slip bowl 23 as shown in FIG. 1. The inner sleeve 49 will be pushed downward relative to the outer sleeve 47. The inner sleeve fingers 50 will extend downward into the clearances 42 to retain the slips 37 in a retracted position. The inner sleeve fingers 50 will radially expand the slip bowl 23 to a diameter greater than the outer diameter of collar 21. The lower portion of the inner sleeve 49 will thus hold the slips 37 in the retracted position and also hold the slip bowl 23 in an expanded position. The operator then inserts the running tool 45 over the upper end of the string of casing 17 and through the blowout preventer (not shown). Once the slip bowl 23 clears collar 21, the operator then applies hydraulic fluid pressure to the chamber 55. This causes the inner sleeve 49 to move upward relative to the outer sleeve 47. The resiliency of the slip bowl 23 causes it to contract from the radially expanded position once the inner sleeve 49 has been removed. In the contracted position, the inner diameter of the slip bowl 23 is less than the outer diameter of the collar 21. In the contracted position, the outer diameter of slip bowl 23 is less than the inner diameter of bore 13. While expanded, the outer diameter of slip bowl 23 will likely be greater than the inner diameter of bore 13. After moving the running tool sleeve fingers 50 upward, the operator lowers the slip bowl 23 until its running shoulder 27 lands on the wellhead housing running shoulder 15. The operator will retrieve the running tool 45. Without the fingers 50 to hold them, the slips 37 will have moved downward by gravity. The conical surfaces 29 cause the slips to move inward until the teeth 41 contact the exterior of casing 17. The operator then will engage the upper end of casing 17 with drilling rig blocks and pull an upward force. The upper end of casing 17 adjacent teeth 41 will move upward as tension is applied. The operator then slacks off. The teeth 41 will grip tightly and hold the casing 17 in tension. In the preferred method, prior to installing a seal (not shown) between casing 17 and wellhead housing bore 13, a honing tool 59 is employed, as shown in FIGS. 4 and 5. Honing tool 59 will smooth the exterior of casing 17 directly above slip bowl 23. Honing tool 59 has a cage 63 that is cylindrical and sized to fit over casing 17. If the operator wishes to delay cutting the casing 17 until after the seal is installed, the cage 63 will be dimensioned to also pass through the blowout preventer and over casing collar 21. Cage 63 has a plurality of windows 65. As shown in FIG. 5, windows 65 are spaced circumferentially apart. Some of the windows 65 are positioned at lower places on cage 63 than others. A honing stone 67 locates moveably in each window 65. Each honing stone 67 is capable of protruding into the interior of cage 63 an appreciable distance and of being pushed outward in each window 65 a selected amount. A lip (not shown) around each window 65 and a shoulder (not shown) around each honing stone 67 prevents the honing stones 67 from falling into the interior of cage 63. A resilient means is employed to urge the honing stones 67 inward. The resilient means in the preferred embodiment is an elastomeric sleeve 69. Elastomeric sleeve 69 extends over the exterior of cage 63. The honing stones 67 have a greater radial thickness than the radial thickness of cage 63. As a result, the contact of elastomeric sleeve 69 with the back of each honing stone 67 pushes the face of each honing stone 67 forward into tight contact with the casing 17. Threads 71 are formed on the upper end of cage 63. A tubular adapter 73 connects threads 71 to a mandrel 75. Mandrel 75 receives a pipe 77. Pipe 77 will be connected to a rotary power source, which could be air, hydraulic, or electric motors. In the operation of the honing tool 59, the user inserts the cage 63 into the clearance between the casing 17 and wellhead housing bore 13. The user then rotates mandrel 75. The sleeve 69 will bias the honing stones 67 inward. The stones 67 will smooth the exterior of casing 17. Once a desired smoothness has been achieved, the operator pulls the honing tool 59 from the wellhead housing 11. The operator then positions and energizes a seal (not shown) above the slip bowl 23. The seal may be of various conventional types. The seal seals between the casing 17 and wellhead housing bore 13. The casing 17 may then be cut. The invention has significant advantages. The emergency casing system enables an operator to install slips over a casing collar and into a wellhead housing. This allows the operator to delay cutting the casing until the slips have been already installed. The honing tool will smooth the exterior of the casing prior to receiving a seal. While the invention has been shown in only one of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention.

An emergency casing hanger can be lowered over casing collars and into a wellhead housing to support a string of casing. The casing hanger has a slip bowl which is slotted so that it can be radially expanded to insert over the casing collar. Slips are carried in the interior of the bowl for gripping the casing once the slip bowl is in position. The running tool has an inner sleeve that holds the slips in a retracted position and holds the slip bowl in an expanded position until the slip bowl clears the collar. Once the running tool has been removed, a honing tool is then lowered over the casing. The honing tool has honing stones mounted in a housing and biased inward for smoothing the exterior of the casing to receive a seal.

You are an expert at summarizing long articles. Proceed to summarize the following text: TECHNICAL FIELD [0001] The present disclosure is directed to a control system and method for a vibratory mechanism. More particularly, the disclosure relates to a system and method for controlling amplitude and frequency of a vibratory mechanism. BACKGROUND [0002] Vibratory work machines such as compactors are often employed to compact soil, gravel, asphalt, and other materials. These vibratory work machines include plate-type compactors and rotating drum compactors. A typical drum compactor has a drum assembly with one or more drums for compacting the material. The drum assembly includes a vibratory mechanism having two or more weights arranged on a shaft rotatable about a common axis within an interior cavity of the drum for inducing vibrations on the drum. The weights are eccentrically positioned with respect to the common axis and are typically movable with respect to each other about the common axis to produce varying degrees of imbalance during rotation of the weights. [0003] The vibratory mechanism provides one or more frequency and amplitude settings. In operation, the vibration amplitude and frequency of a compactor may be changed by a user to suit a particular application. The suitable amplitude and frequency of the vibration may vary depending on the characteristics of the material to be compacted. For example, the vibration amplitude and frequency suitable for compacting gravel for a road may be different from the vibration amplitude and frequency suitable for compacting soil for a footpath. Also, a compacting process may often require compaction with different amplitude and frequency levels at the beginning and end of the process. Furthermore, when a material such as asphalt cools down, its hardness often changes. As a result, compaction with different amplitude and frequency levels may be required based on the temperature of the material. [0004] Vibration amplitude and frequency determine the quality of the compaction, as well as the efficiency of the compaction process. Typically, the amplitude of the vibrations produced by the eccentric weights in the drum assembly may be varied by positioning the weights with respect to each other about their common rotational axis to vary the average distribution of mass (i.e., the centroid) with respect to the rotational axis. In general, vibration amplitude increases as the centroid moves away from the rotational axis of the weights and decreases toward zero as the centroid moves toward the rotational axis. It is also known that varying the rotational speed of the weights about their common axis may change the frequency of the vibrations. [0005] A known vibratory mechanism allows a user to select a desired vibration frequency from one or more possible frequencies independent of the selection of a desired vibration amplitude. In some cases, the vibratory mechanism may enable the user to adjust only vibration amplitude while a vibration frequency remains fixed or uncontrolled, or may enable the user to adjust only vibration frequency while vibration amplitude remains fixed or uncontrolled. For example, U.S. Pat. No. 4,481,835 discloses a device that can continuously adjust a vibration amplitude. However, these known vibratory mechanisms do not establish any relationship or dependency between vibration frequency and vibration amplitude. As a result, a user may be permitted to inadvertently select a vibration frequency and amplitude combination that results in unintended decoupling. Decoupling occurs when a compactor vibrates with a vibratory amplitude that is high enough that the compacting drum becomes airborne. [0006] Thus, the present control system is directed to solving one or more of the shortcomings associated with prior art designs and providing a system and method for controlling a vibratory mechanism with more stability and less interference with the machine performance. SUMMARY OF THE INVENTION [0007] In one aspect, a method is provided for controlling a vibratory mechanism. The method includes sensing a vibratory amplitude of the vibratory mechanism and determining a decoupling point of the vibratory mechanism. An output signal is generated based on the determination of the decoupling point for controlling the vibratory amplitude of the vibratory mechanism. [0008] In another aspect, a control system is provided for controlling a vibratory mechanism. The control system includes a sensor configured to sense a vibratory amplitude and a controller coupled to the sensor. The controller is configured to determine a decoupling point of the vibratory mechanism based on the sensed amplitude and to generate an output signal based on the determination of the decoupling point to control the vibratory amplitude of the vibratory mechanism. BRIEF DESCRIPTION OF THE DRAWINGS [0009] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description, serve to explain the principles of the invention. [0010] FIG. 1 is a diagrammatic representation of a vibratory work machine with a control system according to one exemplary embodiment; [0011] FIG. 2 is a cross-sectional view of a compacting drum of the vibratory work machine of FIG. 1 ; and [0012] FIG. 3 is a block diagram describing the logic of the control system shown in FIG. 1 . DETAILED DESCRIPTION [0013] Reference will now be made in detail to exemplary embodiments that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. [0014] As shown in FIG. 1 , a vibratory work machine may be a double-drum compactor 10 used for compacting a material 12 such as soil, gravel, or asphalt to increase the density of the material. While the control system and method for a vibratory mechanism in a double-drum compactor is described, the control system and method is not limited to this application. [0015] The compactor 10 has a first compacting drum 14 and a second compacting drum 16 rotatably mounted on a main frame 18 . The compactor 10 also has an engine 20 that may be used to generate mechanical and/or electrical power for propelling the compactor 10 . The first compacting drum 14 includes a first vibratory mechanism 22 that is operatively connected to a first motor 24 . The second compacting drum 16 includes a second vibratory mechanism 26 that is operatively connected to a second motor 28 . It should be understood from this disclosure that the vibratory work machine may have more or less than two compacting drums and vibratory mechanisms. [0016] The first and second motors 24 , 28 propel the first and second compacting drums 14 , 16 , respectively, and the motors may be operatively coupled to a power source 30 , which may be connected to the engine 20 . The power source 30 may be an electric generator, a fluid pump or any other suitable device for propelling the compactor 10 and providing power to the first and second vibratory mechanisms 22 , 26 and other systems of the compactor 10 . Where the power source 30 provides electrical power, the first and second motors 24 , 28 may be electric motors. Alternatively, where the power source 30 provides mechanical or hydraulic power, the motors 24 , 28 may be fluid motors. The motors 24 , 28 may be operatively coupled to the power source 30 with electrical wires, fluid conduits, or any other suitable connection. [0017] Also, the compactor 10 includes a controller 40 that determines a decoupling point of the vibratory mechanisms 22 , 26 . At the decoupling point, compacting drums 14 , 16 lose their surface contact to the material 12 , and the vibratory mechanisms or compacting drums become airborne. The controller 34 may also be operatively coupled to an operator or user input 42 that enables the operator of the compactor 10 to set, for example, a desired vibratory control characteristic. The vibratory control characteristic may include a vibratory amplitude limit, which will be explained in detail later. The operator input 42 may be a vibratory control knob, lever, switch or any other suitable device that the operator uses to set the vibratory amplitude characteristic. In one exemplary embodiment, the operator input 42 may be a multi-position switch, and each of the switch positions may correspond to one of amplitude limit settings, such as 50%, 100%, and 150% of the decoupling amplitude. The decoupling amplitude is an amplitude at which the compactor 10 decouples. [0018] FIG. 2 illustrates a cross-sectional view of the first compacting drum 14 . The first vibratory mechanism 22 may be approximately centrally mounted within the first compacting drum 14 . However, the precise location of the vibratory mechanism 22 may be varied to suit a particular application. While the vibratory mechanism will be described with respect to the first vibratory mechanism 22 , the vibratory mechanism shown in FIG. 2 may be used for one or both of the first and second vibratory mechanisms 22 , 26 shown in FIG. 1 . [0019] In the exemplary embodiment shown in FIG. 2 , the vibratory mechanism 22 includes a housing 44 that is rigidly fixed to the compacting drum 14 , an inner eccentric weight 32 that is connected to an inner shaft 34 , and an outer eccentric weight 36 that is connected to an outer shaft 38 . An inner flexible coupling 46 and an outer flexible coupling 48 may be provided for rotating the inner shaft 34 and the outer shaft 38 , respectively. [0020] In general, the vibratory mechanism 22 produces independent continuous or infinite variation of both the amplitude and the frequency. For example, the vibratory mechanism 22 changes the relative positions or relative phase of the inner and outer eccentric weights 32 , 36 to vary the magnitude of the imbalance and the vibratory amplitude produced by rotation of the inner and outer eccentric weights 32 , 36 about their axes. Additionally, the frequency of the vibrations produced by the vibratory mechanism 22 may be varied by changing the rotational speed of the inner and outer weights 32 , 36 . Thus, the frequency of the vibrations produced by the weights 32 , 36 increases as the rotational speed of the weights 32 , 36 increases. [0021] The first motor 24 may be connected to the inner and outer couplings 46 , 48 via a gearbox 50 . A phase control device 52 may be coupled to the gearbox 50 to change the relative positions of the inner and outer shafts 34 , 38 and, thus, the relative positions or phase of the inner and outer eccentric weights 32 , 36 to be continuously or infinitely varied. [0022] As shown in FIG. 2 , the compactor 10 also includes a vibratory amplitude sensor 54 . In one example, the vibratory amplitude sensor 54 may be an accelerometer that can sense the amplitude of the vibrations produced by the compactor 10 , and it may be fixed to a portion of the compacting drum 14 . The accelerometer may also sense the frequency of the vibrations. In addition, the compactor 10 may include a phase sensor 56 connected to the gearbox 50 to measure the relative positions or relative phase of the inner and outer weights 32 , 36 and the inner and outer shafts 34 , 38 . The compactor 10 may also have a speed sensor 58 to measure the rotational speed of the inner and outer weights 32 , 36 and the inner and outer shafts 34 , 38 . [0023] The compactor 10 has the controller 40 electrically connected to the operator input 42 , the phase control device 52 , and the vibratory amplitude sensor 54 . The controller 40 may also be electrically connected to the other sensors. The controller 40 includes a processor for determining the coupling point and generate an output signal to control the amplitude. [0024] FIG. 3 illustrates a schematic block diagram describing an exemplary logic that may be used with the controller 40 to control the vibration amplitude of the compactor 10 shown in FIG. 1 . In one exemplary embodiment, the controller 40 determines a decoupling point of the vibratory mechanism 22 based on the vibratory amplitude sensed by the vibratory amplitude sensor 54 and a predetermined reference vibratory amplitude. The reference vibratory amplitude may be empirically determined, for example, through test runs of the compactor 10 with the drums suspended off the ground, and may be prestored in the controller 40 . This predetermined reference vibratory amplitude corresponds to the decoupling point of the vibratory mechanism 22 . The reference vibratory amplitude may be in a graphic form, such as a sinusoidal wave. [0025] By comparing the sensed amplitude with the reference amplitude, the controller 40 determines a decoupling point of the vibratory mechanism 22 . For example, when the decoupling occurs, the sinusoidal amplitude signal from the sensor 54 may have large amplitude differences between its polarities. Based on the amplitude differences, the controller 40 generates an amplitude control output signal to the vibratory mechanism. In response, the vibratory mechanism vibrates at an amplitude corresponding to the output signal. In one embodiment, the controller 40 may also generate another signal to vary the vibratory frequency of the vibratory mechanism 22 based on the value of the amplitude control output signal. INDUSTRIAL APPLICABILITY [0026] Referring to FIGS. 1-3 , the vibratory amplitude sensor 54 , such as an accelerometer, senses a vibratory amplitude of the compactor 10 . A signal representing the sensed vibratory amplitude is sent to the controller 40 . [0027] Upon receipt of the sensed vibratory amplitude signal, the controller 40 compares the sensed amplitude with a reference amplitude stored in the controller 40 . In one example, the reference amplitude may be in a sinusoidal wave form that represents the amplitude at which the vibratory mechanism 22 decouples, i.e., the amplitude at which the compactor 10 becomes airborne. By comparing the sensed amplitude and the reference amplitude, the controller 40 determines whether the sensed amplitude is below or above the reference or decoupling amplitude. In one embodiment, the controller 40 determines whether the sensed amplitude is below or above the reference or decoupling amplitude via analysis of the dynamic signal from the sensor 54 . When the controller 40 determines that the sensed amplitude is below the reference amplitude, it will send an output signal to increase the amplitude to the vibratory mechanism 22 . On the other hand, when the controller 40 determines that the sensed amplitude is above the reference amplitude, it will send an output signal to decrease the amplitude to the vibratory mechanism 22 . Based on the output signal from the controller 40 , the vibratory mechanism 22 adjusts the phase or positions of the eccentric weights 32 , 36 to alter the amplitude of the vibratory mechanism 22 . The controller 40 may repeat these steps in a closed loop manner so that the amplitude of the vibratory mechanism is kept close to the decoupling amplitude. [0028] In one exemplary embodiment, the operator may set an amplitude characteristic, such as an amplitude limit, via the operator input 42 . When the operator desired to obtain the optimum compaction result without decoupling, then the amplitude limit should be set to 100% of the decoupling amplitude. If the amplitude limit is set, for example, at 50% of the decoupling amplitude, then the output signal is multiplied by 0.5, and the vibratory mechanism 22 provides the amplitude well below the decoupling amplitude, i.e., 50% of the decoupling amplitude. The operator may choose this low setting when a slow compacting process is desired. On the other hand, if the amplitude limit is set, for example, at 150% of the decoupling amplitude, then the output signal is multiplied by 1.5, and the vibratory mechanism 22 provides the amplitude well above the decoupling amplitude, i.e., 150% of the decoupling amplitude. The operator may choose this high setting to intentionally cause decoupling of the vibratory mechanism 22 , for example, when compacting the material at the beginning of the compaction process. Thus, an operator is able to most effectively utilize a compactor for a given application. While these steps are described with respect to the first vibratory mechanism 22 , the controller 40 may control the amplitude of the second vibratory mechanism 26 independently in a similar manner. [0029] It will be apparent to those skilled in the art that various modifications and variations can be made in the disclosed system and method without departing from the scope of the invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope of the invention being indicated by the following claims.

A method is provided for controlling a vibratory mechanism. The method includes sensing a vibratory amplitude of the vibratory mechanism and determining a decoupling point of the vibratory mechanism. An output signal is generated based on the determination of the decoupling point for controlling the vibratory amplitude of the vibratory mechanism.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a raised floor made up of modular slabs mounted on vertical supports which are separated from each other and which rest on the ground. 2. Discussion of Background and Relevant Information Raised floors known today are constituted of modular, usually square, slabs which are attached to one another in a horizontal plane and whose tops rest on horizontal supporting plates made up of the upper horizontal heads of vertical supports separated from each other. Each of these supports comprises a lower base fixed to the ground and a vertical bonding element, of fixed or adjustable length, between the lower base fixed to the ground and the upper support head of the slabs. Up to the present time, slab tops have usually been placed quite simply on the upper support head of each support, their position on said head being determined by upwardly projecting elements held by the upper head of the support. These projecting elements are generally constituted of splinters which, in the case of square or rectangular slabs, are placed at regular intervals at right angles to each other around the vertical support axis, on which said axis the tops of four adjacent slabs merge. The splinters are inserted loosely in demarcated intervals between the lower parts of the slab edges in such a way that the assembly of the adjacent slabs on the support is relatively loose and the resulting floor is therefore not perfectly stabilized. Another type of known raised floor assembly consists of supports whose heads possess slots into which the edges of the modular slabs are fitted, but the assembly of the adjacent slabs on the support obtained according to this process is also relatively loose, because a certain amount of play needs to be maintained for the purpose of fitting the edges of the slabs into the slots of the supports in order to facilitate assembly and to compensate for any expansion of the slabs. A known example of such an assembly is given in the context of U.S. Pat. No. 5,052,157 filed under the name of DUCROUX et al; another example is constituted by the floor described in German Patent Publication No. 2,107,898 filed under the name of CENTRAL FLOORING LTD. in which the support heads possess a protuberance against which the truncated tops of the slabs rest. Although the amount of play may be reduced in such an assembly, it cannot be completely eliminated for fear of raising the slabs in the event of expansion. SUMMARY OF THE INVENTION This invention aims to remedy the disadvantages described above by providing a slab assembly device ensuring a firm hold on these slabs once they are fixed on the upper heads of their supports. For this purpose, the raised floor, whose surface consists exclusively of modular slabs 1 in the shape of a regular polygon, presenting along their sides vertical edges 6 perpendicular to the plate 7 forming the base surface of said slabs 1, sustained at their tops by vertical supports 2 resting on the ground, is characterized in that the upper head 5 of the vertical supports 2 is fitted with radial slots 4 which are usually rectangular and which terminate in the periphery of said upper head 5, the width of said radial slots 4 being so determined as to cause a tightening through vertical fitting into a radial slot 4 of the vertical edges 6, facing each other, said vertical edges 6 belonging to two adjacent slabs 1. BRIEF DESCRIPTION OF THE DRAWINGS Non-limitative examples of various embodiments of the invention will now be described with reference to the accompanying drawings in which: FIG. 1 is a perspective view of the assembly device according to the invention ensuring the maintenance of the square or rectangular slabs on a common support designed to hold four slabs. FIG. 2 is a vertical section view along line II--II of FIG. 1. FIG. 3 is a plan view of a square-shaped floor slab. FIG. 4 is a side-face view of the slab in FIG. 3 as seen from the left of this figure. FIG. 5 is a perspective view of a variant embodiment of the square or rectangular slab assembly device. FIG. 6 is a vertical section view along line VI--VI of FIG. 5. FIG. 7 is a side-face view of a slab according to a variant embodiment of the raised floor. FIG. 8 is a plan view of a square-shaped slab of the floor according to a variant embodiment of the raised floor. FIG. 9 is a side-face view of the slab in FIG. 8 as seen from the left of this figure. FIG. 10 represents a view similar to that of FIG. 9 according to another variant of the slab. FIGS. 11 and 12 are plan views of a floor of a square-shaped slab of the floor presenting the two possible forms of dividing the bosses on the slab edges. FIG. 11a shows a portion of FIG. 11 in greater detail. FIG. 13 is a plan view of a raised floor according to a variant of the invention in which the slabs are in the shape of an equilateral triangle. FIG. 14 is a plan view of a floor slab made of sheet metal cut and folded into the form of an equilateral triangle. FIG. 15 is a side-face view of the slab in FIG. 14 as seen from the left of the figure. FIG. 16 is a larger-scale, partially cross-sectional, plan view of the zone in which six adjacent triangular slabs are attached to a common support. FIG. 17 is a partial vertical section view along line XVII--XVII of FIG. 16. FIG. 18 is a bottom view of the six adjoining slabs represented in FIG. 16. FIG. 19 is a bottom view of an end slab made of sheet metal cut and folded into the shape of an isosceles trapezium. FIG. 20 is a side-face view of the end slab represented in FIG. 19. FIGS. 21, 22, 23, 24, 25 and 26 are front and axial section half-views of various embodiments of fixed-height triangular slab supports. FIG. 27 is an overhead view of the variant embodiment of the support presented in FIG. 26. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The assembly device represented in FIGS. 1 to 3 is designed to ensure the maintenance of horizontal modular slabs 1, square or rectangular, of a raised floor on vertical supports 2 resting on the ground on which the raised floor is to be mounted. These vertical supports 2 are separated from each other by a distance corresponding to the dimensions of the modular slabs 1. Each vertical support 2, of fixed or adjustable height, comprises, on its lower part, a ground support base, not represented in the drawing, and, on its upper end, a horizontal support head 5 on which the tops of modular slabs 1 rest. In FIG. 1, only two slabs are partially represented, but it is clear that each vertical support 2 serves to support four square or rectangular slabs 1. These four slabs 1 are attached to each other, that is to say that their vertical edges 6 are fixed against each other, and the tops of the four adjacent slabs are merged together, as seen from a plan view in point O through which the vertical axis zz' of the support 2 passes. According to the invention, the width of the rectangular slots 4, fitted on the upper head 5 of vertical supports 2 and terminating in its periphery, is so determined as to cause a tightening of vertical edges 6, facing each other, when said vertical edges 6, belonging to two adjacent slabs 1 are fitted vertically into a radial slot 4. FIGS. 3 and 4 represent a variant of square-shaped modular slabs according to which the edge 6 of said slab spreads horizontally over a length which is less than that of a side of the slab, being centered on the middle of the side. FIGS. 5 and 6 represent a slab assembly device according to another variant. In FIGS. 5 and 6, each edge 6 of a square or rectangular-shaped slab 1 is formed by a lateral rim, folded at right angles towards the bottom of the upper plate or plate portion 7 of slab 1. This edge 6 extends over a part of the length of the side of the slab, terminates at a distance from the top O of the slab and is extended towards this top for a short distance by a vertical joining edge of lesser height constituting a locking element of the slab 1 on the upper horizontal head 5 of a vertical support 2. For this purpose, the head 5 possesses four rectangular radial slots 4, terminating in the periphery of the circular or polygonal head 5, converging towards the center O and distributed regularly at right angles to each other around the vertical axis zz' of the support 2. Each locking slot 4 is rectangular in shape and its width e is equal, in the case of edges without bosses, to twice the thickness of a joining edge 3 of reduced height. The radial depths, and according to axis zz' of each slot 4, are sufficient to receive the whole of the joining edge 3, thereby allowing the corner of the slab 1 to rest on the central part of head 5 without there being contact between the vertical slices 8 of the parts 3 of the edges 6 ensuring the joining of slabs 1 and the vertical bottom 9 of the slots 4. As may be seen from a study of FIG. 6, the adjacent slabs 1 are firmly secured on the head 5 of the support 2 by their joining edges 6 which are inserted tightly in their locking slots 4 and are held close to each other due to the fact that the thickness e of each slot 4 is equal to twice the thickness of the edges 6. FIG. 7 is a side-face view of the slabs represented in FIGS. 5 and 6. FIGS. 8, 9 and 10 illustrate a variant embodiment of the slabs according to the invention in which the end 3 of the edge 6 ensuring the fastening of each slab 1 in a radial slot 4 is made up of an elastic strip 10 which is obtained by means of a vertical cut 11 or horizontal cut 12 in the edge 6. In these same figures, a boss 13, shown in greater detail in FIG. 11a, is represented on half of the elastic strips, this boss corresponding to another embodiment of the slabs. According to this variant, one elastic strip in two is fitted with a boss 13 according to the distribution illustrated in FIGS. 11 and 12. These figures represent, in the case of square slabs, the two possible distributions of the bosses allowing the assembly of the slabs according to the invention. It is obvious that the shape of the slabs is not limitative and that the same results would be achieved with triangular or hexagonal slabs. The purpose of the elastic strips 10 is to make it possible to fix the slabs on the supports, this fixture presenting a certain elasticity, due to the strips, whilst at the same time maintaining a tight assembly of said strips 10 in the slots 4 provided on the heads 5 of the supports. Moreover, the addition of a boss on one of the two strips facing towards the interior of a slot 4 makes it possible to create a certain play between the surfaces 7 of the corresponding adjacent slabs. This illustrates how elastic strips fitted with bosses preserve play between the surfaces of the slabs which may therefore expand, for example as the result of heat, without this expansion causing the slabs to rise, even if the expansion of one or more slabs is greater than the play between the same slabs, the elasticity of the assembly allowing a relative movement of the slabs with regard to their support in the horizontal plane without causing upheaval phenomena. In addition, the slabs 1 will firmly fit onto their support 2 by means of the tight assembly of the strips in the slots 4. The result is a floor on which the two kinds of play have been disassociated. The play concerning the slots is eliminated thereby allowing a firm assembly of the edges 6 of the slabs 1 in the radial slots 4. The play between the base plates 7 of the slabs 1 is preserved and even accentuated by the elasticity of the bonding between the slabs and their supports, thus making it possible to offset all the problems of expansion. Obviously, the play between the base surfaces 7 of the adjacent slabs 1 obtained by adding a boss on the elastic strips 10 could equally well be achieved with another device, for example through folding the strips 10, but in this case, a regular distribution of the play between the base surfaces 7 would be harder to achieve than with bosses. FIG. 13 shows a raised floor according to the invention consisting of a set of horizontal modular slabs 1, which are attached to each other and are of the same size and the same equilateral triangle shape. The tops of the individual slabs 1 are merged in points O constituting the nodes of a mesh network with triangular meshes formed by the set of slabs 1. Each node O of the network constitutes the common top of six triangular slabs 1 distributed regularly around a vertical axis passing through the node O and constituting at the same time a regular hexagon. A subjacent support 2 is associated to each node O, which said subjacent support will be described in detail below. The support may consist of an independent element, for example such as one of the element 16, 21, 25, 29, or 31 illustrated in FIGS. 21 to 27. At its lower end, the support 2 rests on the ground on which the raised floor is mounted. From the preceding description it may therefore be seen that each triangular slab 1 rests on the floor at the three points O formed by the three tops of the equilateral triangle constituted by said slab. The triangular-shaped modular slabs 1 are only used if the length L of the surface to be covered by the raised floor is equal to a multiple of the height h of each triangular slab 1. However, as may be required in exceptional circumstances, provision is made, again according to the invention, to complete the assembly of the raised floor, in the neighborhood of the walls, by means of supplementary end slabs 14 , each in the form of an isosceles trapezium corresponding to three attached standard main triangular slabs 1. In other words, the small base of each end slab 14 is equal in length to the side of the triangular slab 1, the length of its large base is equal to twice the length of the side of a triangular slab 1, and the height of an end trapezoid slab 14 is equal to the height h of a triangular slab 1. The median area of the large base of each end slab 14 is arranged so as to be capable of receiving a standard support or a standard jack, as will be seen below. The end slabs 14 ensure good floor stability along the walls, once adjusting cuts have been made. FIG. 14 shows various scenarios explaining this necessity. The section carried out in the direction of arrow a reveals that the triangular main slabs 1 give satisfactory results, that is to say an adequate support along length a1. Lengths a2 and a3 show three other adjustment possibilities by means of end slabs 14 which are truncated in order to obtain improved results. The section carried out in the direction of arrow b shows that the small surfaces x of the triangular slabs 1, remaining after cutting and indicated by section lining, are inadequate and unequal to the task of providing satisfactory support along length b1. In contrast, end slabs 14 are used along length b2, and the parts remaining after cutting, represented in section lining, have a sufficient surface to provide a satisfactory support. The section carried out in the direction of arrow c shows that satisfactory stability is obtained, along length c1, using the end slabs 14, but in this case triangular slabs 1 could also have been used. The section carried out in the direction of arrow d reveals that satisfactory stability along length d1 is obtained using cut end slabs 14, whereas the triangular slabs 1 would involve small cuts x which would be impossible to fix. In the angles, the sectional intersections--in directions a and c, on the one hand, and in directions b and d, on the other hand--are made using end slabs 14. FIGS. 14, 15, 16, 17 and 18 represent the triangular-shaped slabs corresponding to the variant of the invention under consideration. The characteristics are the same as for modular slabs of any regular polygonal shape. The subjacent support 2 comprises an upper support face 5 in which six converging radial slots are bored, these slots being distributed at regular intervals and at an angle of 60° to each other, on a circle of center O where the tops of six adjacent triangular slabs 1 are merged, as shown in FIG. 16. If the support face 5 is circular, it may be seen that each corner of a triangular slab 1 rests on a sector at an angle of 60° of the circular support face 5. Parts 3 of edges 6, folded downwards, are inserted in the converging radial slots 4. As the width e of each slot 4 is chosen equal to twice the thickness of the parts 3 of the edges 6, said edges 6 of two adjacent triangular slabs 1 are packed and blocked against each other in the same slot 4, as may be seen from a study of FIGS. 17 and 18, thereby ensuring a firm fixture of the slabs 1 on the support 2. The converging forms of the slots 4 provide the horizontal hold of the slabs 1, while the three-point support for each slab 1 gives perfect stability, thus eliminating any risk of vertical movement which might lead to disassembly, but at the same time ensuring easy, fast and effortless dismantling. Moreover, each support 2 is particularly stable since it is simultaneously retained by six adjacent triangular slabs 1. With a view to making the representation as clear as possible, in FIGS. 14, 15, 16, 17 and 18 the edges 6 are shown in their simplest form, that is to say without height reduction at their extremities, without strips and without bosses. It is clear that all these different variants may be applied to triangular-shaped slabs. In particular, in the presence of bosses 13 on the elastic strips 10, the width of the radial slots 4 will be equal to twice the thickness of the strips 10 plus once the thickness of the boss 13. The view from below represented in FIG. 18 gives a good illustration of the way in which the edges 6 of triangular slabs 1 are attached to each other, thereby establishing the continuity of the floor. However, due to the fact that there is a separation plane between two adjacent slabs 1, the floor displays good acoustic performance since the separation planes between the slabs break horizontal sound transmission, particularly in the case of the variant in which parts 3 of edges 6 are in the shape of elastic strips fitted with bosses, because in this case the base plates 7 of the slabs are separated from each other by a play corresponding to the thickness of the boss. Moreover, given that the triangular slabs 1 are small in size, they mitigate the membrane effect obtained with larger surfaces. FIGS. 19 and 20 represent an arrangement of a trapezoid end slab 14. This end slab may also, like the triangular slab 1, be made up of sheet metal cut and folded so as to form a trapezoid base plate 35 which presents, on its sides, rims folded at right angles in the same direction and culminating at a same distance from the tops of the base plate 35. The two inclined sides and the small base of the trapezoid slab 35 each comprise two distinct edges 15 which are obtained by creating a recess 34 centered on the edge of the large base. This recess 34 between the two edges 15 of the large base is needed to attach the end slab 14 to the subjacent supports. With reference to FIGS. 21 to 27, a description will now be given of various non limitative embodiments of the floor supports. These supports, which are constituted by independent elements designed to receive, according to a preferred variant of the considered invention, on their upper faces, the triangular slabs 1 and the trapezoid end slabs 14 and to keep them assembled, determine the height of the plenum obtained, that is to say, of the empty space under the floor which is equal to their own height. Each support comprises a horizontal upper face 5 in which are formed the six converging radial slots 4 distributed, at an angle of 60° in relation to each other, around the center O of the upper face 5. The support 16 represented in FIG. 21, is made in a single steel piece, in a general upwardly converging tapered shape, terminated at its lower part by an external flange 17 constituting a support base on the ground. The upper face of the upper horizontal wall 18 of the support 16 constitutes in itself the planar support and fastening face 5 of the slabs. The radial slots 4 are bored both in the upper wall 18 and in the upper part of the tapered lateral wall. In the variant represented in FIG. 22, the support 16 comprises a full upper wall 20 onto which is fastened, for example by welding, an added circular plate 19 in which the radial slots 4 are formed. In the variant represented in FIG. 23, the support 21 is made up of three parts, assembled together by welding or otherwise, namely a lower horizontal base 22, an upper horizontal head 23 in which the radial slots 4 are bored in order to fasten the slabs, and an intermediate vertical body 24 stretching between the base 22 and the head 23, all these elements being preferably fabricated in steel. In the variant represented in FIG. 24, the support 25 comprises a lower block 26, of tapered shape and possibly made of matter which is inert to fire such as resin, plastic matter, plaster, cement, anhydrites, calcium silicate, conglomerate wood, etc. An upper circular steel plate 27 is fixed on the upper face of block 26, in which said plate 27 are cut the radial slots 4 which lie above corresponding radial grooves 28 formed on the upper part of block 26. In the variant represented in FIG. 25, the support 29 is made up of a molded block, with a grooved structure, and fabricated of light alloy, plastic material, compressed wood, resin, etc. The support 29, of a general taper shape, possesses in its upper horizontal wall six molded radial grooves 30 placed at an angle of 60° in relation to each other as described in the previous embodiments. FIGS. 26 and 27 show a variant in which the support 31 is made up of a hexagonal shape in molded material hollowed out by six radial slots 32 and equipped with six reinforcement grooves 33 shifted by 30° compared to the radial slots, these reinforcement slots 33 making it possible both to increase the ground support surface and the slab support surface.

A raised floor having an upper surface in the form of regular polygon-shaped modular slabs, each having a substantially horizontal plate portion and downwardly extending side edges. The plate portion of each slab is supported on the top of substantially vertical ground-engaging supports. Around the periphery of a top member of each vertical support are a plurality of radial slots for receiving pairs of confronting side edges of adjacent slabs for securing the slabs to the supports.

You are an expert at summarizing long articles. Proceed to summarize the following text: TECHNICAL FIELD OF INVENTION [0001] The present invention relates to a new apparatus and method for use in subterranean exploration. The present invention provides a system and method for rapid rig-up and rig-down of a mechanism that is mountable to a drill floor of a conventional drilling rig, such as a pipe racking mechanism. Still more particularly, the present invention discloses an apparatus and method for rapid deployment of a drill floor mounted pipe racking system during rig-up at a new drilling location. BACKGROUND OF THE INVENTION [0002] In the exploration of oil, gas and geothermal energy, drilling operations are used to create boreholes, or wells, in the earth. Subterranean drilling necessarily involves the movement of long lengths of tubular sections of pipe. At various intervals in the drilling operation, all of the drill pipe must be removed from the wellbore. This most commonly occurs when a drill bit wears out, requiring a new drill bit to be located at the end of the drill string. It can also be necessary to reconfigure the bottom-hole assembly or replace other downhole equipment that has otherwise failed. When the drill pipe has to be removed, it is disconnected at every second or third connection, depending on the height of the mast. On smaller drilling rigs used in shallower drilling, every other connection is disconnected, and two lengths of drill pipe, known as “doubles,” are lifted off of the drill string, aligned in the fingers of the rack by the derrickman, and then lowered onto the drill floor away from the well center. On larger drilling rigs used for deeper drilling, every third connection is disconnected and three lengths of pipe, known as “triples,” are lifted off of the drill string, aligned in the fingers of the rack by the derrickman, and then lowered onto the drill floor away from the well center. The doubles and triples are called a stand of pipe. The stands are stored vertically on the rig floor, aligned neatly between the fingers of the rack on the mast. A triple pipe stand is long and thin (about ninety feet long). [0003] Removing all of the drill pipe from the well and then reconnecting it to run back into the well is known as “tripping the pipe” or “making a trip,” since the drill bit is making a round trip from the bottom of the hole to the surface and then back to the bottom of the hole. Tripping the drill pipe is a very expensive and dangerous operation for a drilling rig. Most injuries that occur on a drilling rig are related to tripping the pipe. Additionally, the wellbore is making no progress while the pipe is being tripped, so it is downtime that is undesirable. This is why quality drill bits are critical to a successful drill bit operation. Drill bits that fail prematurely can add significant cost to a drilling operation. Since tripping pipe is “non-drilling time,” it is desirable to complete the trip as quickly as possible. Most crews are expected to move the pipe as quickly as possible. [0004] There are a number of variables that contribute to a very irregular and hostile movement of the pipe stand as it is disconnected and moved to the rack for setting on the drill floor, as well as when it is being picked up for alignment over the wellbore center for stabbing and connection to the drill string in the wellbore. For example, the vertical alignment and travel of the elevator and hoist connection which lift the drill string from the wellbore is cable connected and capable of lateral movement which is translated to the drill string rising from the wellbore. Also, the drill string is supported from the top, and as the derrickman moves the drill string laterally, the accelerated lateral movement of the long length of the pipe stand away from the well center generates a wave form movement in the pipe itself. As a result of the natural and hostile movement of the heavy drill stand, which typically weighs between 1,500 and 2,000 lbs., and drill collars which weigh up to 20,000 lbs., it is necessary for the crew members to stabilize the drill pipe manually by physically wrestling the pipe into position. The activity also requires experienced and coordinated movement between the driller operating the drawworks and the derrickman and floorhands. Many things can go wrong in this process, which is why tripping pipe and pipe racking is a primary safety issue in a drilling operation. [0005] Attempts have been made to mechanize all or part of the pipe racking operation. On offshore platforms, where funding is justifiable and drill floor space is available, large Cartesian racking systems have been employed in which the drill stands are gripped at upper and lower positions to add stabilization, and tracked modules at the top and bottom of the pipe stand coordinate the movement of the pipe stand from the wellbore center to a racked position. Such systems are very large and very expensive, and are not suitable for consideration for use on a traditional land based drilling rig. [0006] An attempt to mechanize pipe racking on conventional land based drilling rigs is known as the Iron Derrickman® pipe-handling system. The apparatus is attached high in the mast, at the rack board, and relies on a system of hydraulics to lift and move stands of drill pipe and collars from hole center to programmed coordinates in the racking board. This cantilever mast mounted system has a relatively low vertical load limit, and therefore requires assistance of the top drive when handling larger diameter collars and heavy weight collars. [0007] The movement of the pipe with this system has proved unpredictable and thus requires significant experience to control. One problem with this system is that it grips the pipe far above the center of gravity of the tubular and fails to control the hostile movement of the drill pipe stand sufficiently to allow for safe handling of the stands or for timely movement without the intervention of drilling crew members. In particular, the system is not capable for aligning the lower free end of the drill stand accurately for stabbing into the drill string in the wellbore without frequent human assistance. As a result of these and other deficiencies, the system has had limited acceptance in the drilling industry. [0008] An alternative system that is known provides vertical lifting capacity from the top drive and a lateral movement only guidance system located near the rack. The system still requires a floorman for stabbing the pipe to the stump as well as to the set-back position. [0009] A primary difficulty in mechanizing pipe stand racking is the hostile movement of the pipe that is generated by stored energy in the stand, misaligned vertical movement, and the lateral acceleration and resultant bending and oscillation of the pipe, which combine to generate hostile and often unpredictable movements of the pipe, making it hard to position, and extremely difficult to stab. [0010] A conflicting difficulty in mechanizing pipe stand racking is the need to move the pipe with sufficient rapidity that cost savings are obtained over the cost of manual manipulation by an experienced drilling crew. The greater accelerations required for rapid movement store greater amounts of energy in the pipe stand, and greater attenuated movement of the stand. [0011] Another primary obstacle in mechanizing pipe stand racking is the prediction and controlled management of the pipe stand movement sufficient to permit the precise alignment required for stabbing the pipe to a first target location on the drill floor and to a second target location within the fingers of the racking board. [0012] An even greater obstacle in mechanizing pipe stand racking is the prediction and controlled management of the pipe stand movement sufficient to achieve the precise alignment required for stabbing the tool joint of the tubular held by the racking mechanism into the receiving tubular tool joint connection extending above the wellbore and drill floor. [0013] Another obstacle to land-based mechanizing pipe stand racking is the lack of drilling floor space to accommodate a railed system like those that can be used on large offshore drilling rigs, as well as the several structural constraints that are presented by the thousands of existing conventional drilling rigs, where the need to retrofit is constrained to available space and structure. [0014] A recent solution to these several obstacles is disclosed in U.S. patent application Ser. No. 13/681,244. This solution provides a relatively large and complex pipe racking mechanism that must be stability erected on the top of a conventional drill floor of a land based drilling rig, where it must also be connected securely to the mast of the drilling rig. [0015] Thus, the best technology for an automatic pipe racking solution creates a significant related obstacle in the transportation and rig-up and rig-down of such a large system. A first obstacle is to efficiently reduce such a large structure into a transportable envelope. A second obstacle is to accomplish the conversion from a truck mounted transportable load to a rigged-up position using the existing equipment for positioning and raising the mast and substructure of the conventional drilling rig. [0016] It is also desirable to minimize accessory structure and equipment, particularly structure and equipment that may interfere with transportation or with manpower movement and access to the rig floor during drilling operations, or that will unreasonably extend the time needed to erect the drilling rig. It is also desirable to ergonomically limit the manpower interactions with rig components during rig-up for cost, safety and convenience. [0017] Thus, the currently best known solution for automatic pipe racking problems presents unique challenges of rig-up, rig-down and transportation. [0018] The various embodiments of the present invention provide for a system and method of efficient rig-up, rig-down and transportation of a drill floor mountable automatic pipe racking device capable of use on a conventional land based drilling rig floor. SUMMARY OF THE INVENTION [0019] The present invention provides a new and novel pipe stand racking system and method of use. In one embodiment, an automatic pipe racker is provided, having a base frame connectable to a drill floor of a drill rig and extending upwards at a position offset to a V-door side of a drilling mast that is also connected to the drill floor. In one embodiment, the base frame is a C-frame design. A mast brace may be connected between the base frame and the drilling mast at a position distal to the drill floor for stabilizing an upper end of the base frame in relationship to the mast. A tensioner may be connected between the base frame and the drilling floor for stabilizing the base frame in relationship to the substructure. [0020] The base frame is connectable to the drill floor of a drill rig, in a position offset to the drilling mast. A pair of base legs is pivotally connected to the base frame, and movable between a retracted position for transportation and an extended position for pivotal connection to the drill floor. A pipe handling mechanism is extendable from the base frame, and capable of moving stands of connected pipe from a racked position on the drill floor to a stabbing position above a drill string component held in a rotary table. [0021] Besides the base frame, the pipe stand racking system may include components such as a lateral extend mechanism connected to the base frame, and extendable between a retracted position and a deployed position. The pipe handling mechanism may further include a rotate mechanism connected to the lateral extend mechanism, and being rotatable in each of the left and right directions. A finger extend mechanism may further be connected to the rotate mechanism, being laterally extendable between a retracted position and a deployed position. [0022] A vertical grip and stab mechanism may be attached to the finger extend mechanism. The gripping mechanism has grippers to hold a tubular pipe or stand of pipe and is capable of moving the pipe vertically to facilitate stabbing. [0023] The automatic pipe racking system is series nested and substantially retractable into the base frame. This property transforms the automatic pipe stand racking system into a structure having a transportable envelope. [0024] In another embodiment, a system is provided for transportation and erection of an automated pipe racker, comprising a base frame connectable to a drill floor of a drill rig, offset to a drilling mast that is also connected to the drill floor. A pair of legs is retractably connected to the base frame, and movable between a retracted position for transportation and an extended position for connection to the drill floor. A mast brace is connectable between the base frame and the drilling mast. A skid assembly is connected to the base frame. The skid assembly is designed to be a platform on which the automatic pipe racker rests during transportation. [0025] In one embodiment, the skid assembly is tiltable to facilitate connection to the drill floor for rig-up. In this embodiment, the skid assembly has an upper skid and a lower skid, with the lower skid pivotally connected to the base frame and movable between an extended position for transportation and a retracted position for connection of the automatic pipe racker to the drill floor for rig-up. [0026] In another embodiment, a retractable standoff is located between the base frame and lower skid. An optional retractable latch may be provided to lock or unlock the position of the lower skid in relation to the base frame. A jack may be provided and located proximate to the upper skid. The jack is extendable to tilt the automatic pipe racker onto the lower skid when the lower skid is in the retracted position. [0027] A ground pivot point is located near the center of gravity of the automated pipe racker when the automatic pipe racker is resting on the skid assembly. The upper skid portion extends substantially (mostly) above the ground pivot. The lower skid portion extends substantially (mostly) below the ground pivot. The ground pivot is located in between the lower and upper skids. In another embodiment, the ground pivot is located near and below the center of gravity of the automated pipe racker when the automatic pipe racker is resting on the skid assembly, such that the automatic pipe racker will rest on the upper skid when the skid is resting on a substantially (mostly) horizontal plane. [0028] As will be understood by one of ordinary skill in the art, the sequence of the steps, and designation of retractable elements disclosed may be modified and the same advantageous result obtained. For example, the functions of the upper and lower skids may be reversed, and other certain elements may be deployed before or after other elements where minor change in sequence does not change the result. BRIEF DESCRIPTION OF THE DRAWINGS [0029] The objects and features of the invention will become more readily understood from the following detailed description and appended claims when read in conjunction with the accompanying drawings in which like numerals represent like elements. [0030] The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention. [0031] FIG. 1 is an isometric view of a drilling rig fitted with an automatic pipe racking system of the type to which the present invention applies. [0032] FIG. 2 is an isometric view of the automatic pipe racking mechanism, illustrated without the drilling rig, and showing a skid assembly mounted to the back side of the pipe racker. [0033] FIG. 3 is an isometric representation of a transport vehicle transporting an automatic pipe racker to a position in alignment beneath the mast connected to the substructure. The transport vehicle is aligned for approach to the collapsed substructure. [0034] FIG. 4 is a continuation of the rig-up process illustrated in FIG. 3 , illustrating deployment of components of the automatic pipe racking system that were previously retracted for transportation. [0035] FIG. 5 is a general side view of an optional embodiment, illustrating the automatic pipe racker resting on its skid assembly, in the transport position on the trailer bed of a truck. [0036] FIG. 6 is a general side view of the base frame of the pipe racker, including an exploded view of a skid assembly normally connected to the base frame. [0037] FIG. 7 is a general side view, illustrating the automatic pipe racker resting on its skid, with the skid assembly shown transitioning into the rig-up position. [0038] FIG. 8 is a general side view, illustrating the automatic pipe racker resting on its skid, with the skid assembly shown in the rig-up position. [0039] FIG. 9 is a continuation of the rig-up process illustrated in FIG. 4 , illustrating movement of the transport vehicle closer to the substructure, tilting the automatic pipe racking system on the transport trailer bed, and connection of deployed components of the automatic pipe racking system to the drill floor and mast. [0040] FIG. 10 is a continuation of the rig-up process illustrated in FIG. 9 , illustrating the removal of the transport vehicle from beneath the mast, and with the automatic pipe racking system supported by its connection to the drill floor and the drill mast. [0041] FIG. 11 is a continuation of the rig-up process illustrated in FIG. 10 , illustrating partial raising of the mast and automatic pipe racking system to a position above the drill floor. [0042] FIG. 12 is a continuation of the rig-up process illustrated in FIG. 11 , illustrating the mast and automatic pipe racking system in the vertical position above the drill floor. DETAILED DESCRIPTION [0043] The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. [0044] FIG. 1 is an isometric view of an automatic pipe racking mechanism 100 including features of the invention disclosed in U.S. patent application Ser. No. 13/681,244, and which embodies a drill floor mounted structure of the type to which the present inventive system and method of raising applies. Drilling rig 10 has a drill floor 14 located over a wellbore 12 . A drilling mast 16 is mounted to drill floor 14 , which has an open V-door side 18 . Racking mechanism 100 is mounted on drill floor 14 , on the V-door side 18 of drilling mast 16 . [0045] Racking mechanism 100 is comprised of a base frame 200 that is pivotally connected to drill floor 14 by floor pins 202 . In one embodiment, base frame 200 is a tapered C-frame that extends upwards from drill floor 14 at a position offset to V-door side 18 of drilling mast 16 . A mast brace 204 is connected between base frame 200 and drilling mast 16 at a position distal to drill floor 14 for stabilizing an upper end of base frame 200 in relationship to drilling mast 16 . In one embodiment, a pair of tensioning members 206 is connected between drill floor 14 and base frame 200 . [0046] In one embodiment, the length of mast brace 204 is controllably adjustable to compensate for deflection of racking mechanism 100 under different payloads which vary with the size of the tubular being handled. Adjustment is also advantageous to accommodate non-verticality and settling of drilling rig 10 . Adjustment is also useful for connectivity to other mechanisms that deliver or receive pipe from racking mechanism 100 . Adjustment is also useful when using mast braces 204 as a connected lifting component of the present raising system. [0047] FIG. 2 is an isometric view of base frame 200 of racking mechanism 100 , illustrating base frame 200 in isolation of the remaining components of racking mechanism 100 and of drilling rig 10 . In one embodiment, base frame 200 includes a pair of deployable legs 210 pivotally connectable at a lower end of base frame 200 . When legs 210 are deployed downward, deployed ends of legs 210 are connected to drill floor 14 (not shown) by floor pins 202 . Retraction of legs 210 provides a shorter transport profile for transporting racking mechanism 100 between drilling sites. [0048] Base frame 200 also includes a pair of deployable arms 212 , pivotally attached to base frame 200 . In one embodiment, when arms 212 are deployed outward, deployed ends of arms 212 are connected to base frame 200 by struts 214 . In this embodiment, mast braces 204 are pivotally connected to the ends of arms 212 , and pivotally connectable to mast 16 . This connectivity increases the spacing between mast braces 204 and mast 16 , providing conflict free mechanical operation of racking mechanism 100 . Retraction of arms 212 and pivotal retraction of braces 204 provides a narrower transport profile for transporting racking mechanism 100 between drilling sites. In another embodiment (best seen in FIG. 3 ), legs 210 , arms 212 and braces 204 fully retract without structural interference, such that each retracts proximate to base 200 for greater transportability. As shown in the present embodiment of base frame 200 , an optional bracket 216 may be provided for supporting mast braces 204 during transport of base frame 200 . Bracket 216 may be attached to struts 214 or mast braces 204 to secure these elements to the mast braces 204 during transport. [0049] Base frame 200 has a skid assembly 220 attached to the side opposite mast 16 . In another embodiment, tensioning members 206 connect each side of base frame 200 to drill floor 14 (not shown) of drilling rig 10 (not shown). Tensioning members 206 stabilize base frame 200 of racking mechanism 100 . In one embodiment, tensioning members 206 are adjustable to stiffen racking mechanism 100 , and to compensate for verticality and the variable deflection of racking mechanism 100 when handling different sizes of drill pipe 50 . [0050] It will be appreciated that the disclosed invention, or a similar automatic pipe racking system, must be capable of rapid disassembly and assembly. In contemporary drilling operations, it is necessary to minimize the downtime of the drilling rig and to “rig down” or disassemble the entire drilling rig to a minimum number of transportable components as quickly as possible. The transportable components must fit within regulated physical dimensions for safe transport on designated highways to remote locations where the drilling activity can resume. [0051] FIG. 3 is an isometric representation of a transport vehicle 900 transporting racking mechanism 100 to a position in alignment beneath mast 16 . Drilling rig 10 has its mast 16 assembled but not raised. Mast 16 is pivotally connected to a substructure 30 that is also not raised. In the embodiment illustrated, mast 16 is optionally supported by a rack, such as a headache rack 40 for safety. In the embodiment illustrated in this view, base frame 200 has a skid assembly 220 attached. [0052] Skid assembly 220 supports racking mechanism 100 on transport vehicle 900 . During transportation, and as illustrated here, lower skid 228 and upper skid 226 support racking mechanism 100 on the trailer bed 910 of transport vehicle 900 . Transport vehicle 900 is maneuvered to position racking mechanism 100 beneath mast 16 . Alternatively, racking mechanism 100 may be placed on the ground on top of skid assembly 220 and positioned into place with equipment such as a fork lift. [0053] FIG. 4 is a continuation of the rig-up process illustrated in FIG. 3 , illustrating deployment of components of racking mechanism 100 that were previously retracted for transportation as shown in FIG. 3 . In particular, arms 212 , mast braces 204 , and legs 210 have been deployed. Optionally, when arms 212 are deployed outward, deployed ends of arms 212 may be connected to base frame 200 by struts 214 to further strengthen their position. [0054] Also illustrated in FIG. 4 , lower skid 228 has been retracted, and a jack 240 ( FIG. 6 ) has been actuated to tilt racking mechanism 100 backwards over pivot center 222 such that racking mechanism 100 is resting on retracted lower skid 228 . Upper skid 226 no longer supports the weight of racking mechanism 100 , as the center of gravity 224 of racking mechanism 100 has shifted below pivot center 222 . [0055] In an optional embodiment, wheel assembly 242 is deployed when jack 240 is actuated to facilitate minor realignment of racking mechanism 100 relative to drill floor 14 as may be necessary. [0056] FIG. 5 is a close-up side view, illustrating the automatic pipe racking mechanism 100 resting on skid assembly 220 in the transport position on trailer bed 910 of a transport vehicle 900 . [0057] In the embodiment illustrated, skid assembly 220 has a skid ground pivot 222 located proximate to where lower skid 228 is pivotally connected to base frame 200 . Ground pivot 222 is also located near the center of gravity 224 of racking mechanism 100 when the automatic pipe racking mechanism 100 is resting on skid 220 . In this embodiment, an upper skid portion 226 extends above ground pivot 222 , and lower skid portion 228 extends below ground pivot 222 . [0058] In this transport position, both lower skid 228 and upper skid 226 are in contact with trailer bed 910 of transport vehicle 900 . This configuration provides for stability during transport, as both lower skid 228 and upper skid 226 support the weight of racking mechanism 100 as transport vehicle 900 accelerates, decelerates and navigates turns, shifting the weight of racking mechanism 100 on trailer bed 910 . [0059] In the embodiment illustrated, one or more skid stand-offs 230 are pivotally connected to lower skid portion 228 at pivot 232 . Retractable stand-offs 230 are pivotally connected to base frame 200 at pivots 234 . Stand-offs 230 hold lower skid 228 in the deployed position. Also seen in the embodiment illustrated, an optional jack 240 is located proximate to the upper end of upper skid 226 , opposite to the ground pivot 222 end of upper skid 226 . [0060] FIG. 6 is a general side view of the lower portion of base frame 200 , including an exploded view of skid assembly 220 in accordance with an embodiment of the present invention. In this view, upper skid 226 is shown attached to base frame 200 . Lower skid 228 is shown detached from pivot 222 . Stand-offs 230 are shown having wheels 246 attached, which are mostly hidden from view in the other figures. [0061] To transition racking mechanism 100 to a rig-up position, stand-offs 230 are moved from the extended position to the retracted position, causing lower skid 228 to retract into proximity with base frame 200 . In the embodiment illustrated, this movement exposes wheels 246 beneath lower skid 228 . This will permit wheels 246 to engage trailer bed 910 to facilitate corrective alignment of racking mechanism 100 with drill floor 14 and mast 16 if such alignment is necessary. Such engagement will occur in the next step of tilting. [0062] Still referring to FIG. 6 , a jack 240 is attached to a jack frame 244 having a wheel assembly 242 attached. To transition racking mechanism 100 to a rig-up position, jack 240 may be actuated, causing racking mechanism 100 to tilt onto wheels 242 of retracted lower skid 228 . In the embodiment illustrated, extension of jack 240 exposes wheel assembly 242 beneath upper skid 226 . This permits wheels 246 to engage trailer bed 910 to facilitate corrective alignment of racking mechanism 100 with drill floor 14 and mast 16 if such alignment is necessary. [0063] FIG. 7 is a general side view, illustrating the automatic racking mechanism 100 resting on skid assembly 220 , with skid assembly 220 shown transitioning from the transport position to the rig-up position. In this intermediate step, stand-offs 230 are retracted, which retracts lower skid 228 about pivot 222 to a position closer to base frame 200 . Since center of gravity 224 is located on the upper skid 226 side of ground pivot 222 , racking mechanism 100 does not tip uncontrollably onto wheels 246 of lower skid 228 . [0064] FIG. 8 is a general side view, illustrating automatic racking mechanism 100 resting on skid assembly 220 , with skid assembly 220 shown in the rig-up position. Jack 240 has been actuated so as to tilt racking mechanism 100 rearward until wheels 246 of lower skid 228 contact trailer bed 910 . Additionally, wheel assembly 242 comes into engagement with trailer bed 910 to further facilitate corrective alignment of racking mechanism 100 with drill floor 14 and mast 16 if such alignment is necessary. [0065] FIG. 9 is a continuation of the rig-up process illustrated in FIG. 4 , and as illustrated in FIGS. 5-8 . FIG. 9 illustrates movement of transport vehicle 900 into position closer to substructure 30 . Tilted automatic racking mechanism 100 on transport trailer bed 910 is now in position for connection of the deployed components of racking mechanism 100 to drill rig 10 . [0066] As seen in FIG. 9 , by tilting racking mechanism 100 , racking mechanism 100 is now positioned such that legs 210 extend appropriately over drill floor 14 to align legs 210 for pivotal connection to drill floor 14 with floor pins 202 . Mast braces 204 may also be pivotally connected to mast 16 in this position. Optionally, a pair of tensioning members 206 are connected between drill floor 14 and base frame 200 . Tensioning members 206 further stabilize base frame 200 in relationship to drilling rig 10 . Alternatively, tensioning members 206 may be connected after raising automatic pipe racking mechanism 100 . Optionally, a frame support 40 such as the headache rack, can be positioned underneath mast 16 for safety. [0067] FIG. 10 is a continuation of the rig-up process illustrated in FIGS. 3-9 . FIG. 10 illustrates transport vehicle 900 removed from beneath mast 16 , and racking mechanism 100 remains suspended by its connections to drill rig 10 . When transport vehicle 900 departs, the racking board 20 can be attached to the mast 16 as shown. [0068] FIG. 11 is a continuation of the rig-up process illustrated in FIGS. 3-10 , illustrating partial raising of mast 16 and automatic pipe racking mechanism 100 towards a vertical position over drill floor 14 . This step is conventionally performed by extension of hydraulic cylinders sized for the task. As mast 16 is raised, automatic pipe racking mechanism 100 is pulled into position by mast braces 204 through arms 212 , pivoting automatic pipe racking mechanism 100 on the pivotal connection 202 of legs 210 to drill floor 14 at floor pins 202 . Tensioning members 206 are not shown connected between automatic pipe racking mechanism 100 and drill floor 14 , but they may be connected at this time as well. [0069] FIG. 12 is a continuation of the rig-up process illustrated in FIGS. 3-11 , illustrating mast 16 and automatic pipe racking mechanism 100 in the vertical position above drill floor 14 . Mast braces 204 are no longer supporting the weight of automatic pipe racking mechanism 100 . In this position, the verticality of automatic pipe racking mechanism 100 can be adjusted by adjustment of mast braces 204 . [0070] As described, the relationship of these elements has been shown to be extremely advantageous in providing an automatic pipe racking mechanism 100 that can be mounted to a conventional drill floor, and that is capable of lifting and moving drill pipe between a racked position within a largely conventional racking board and a stabbed position over a wellbore. [0071] Having thus described the present invention by reference to selected embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered desirable by those skilled in the art based upon a review of the foregoing description of embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.

The present invention relates to a new apparatus and method for use in subterranean exploration. The present invention provides a rapid rig-up and rig-down of a drill floor mounted device such as a pipe racking system. In particular, the present invention discloses a system and method for rapid deployment of a drill floor mounted pipe racking system that is capable of being retrofit to an existing drilling rig.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS This is an original non-provisional application claiming benefit of U.S. Provisional Application 60/765,766, filed Feb. 6, 2006, which is incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic retractable ladder that is installed on an access panel hinged on a framing structure that surrounds an opening into the ceiling for access to an attic space. The access panel and the retractable ladder have two positions. In the first position the access panel automatically closes the opening into the ceiling and the retractable ladder is stowed or retracted on top of the access panel, i.e. in the attic. In the second position the access panel automatically uncovers the opening of the ceiling and the retractable ladder automatically deploys or extends to reach the ground. The automatic opening of the access panel and the automatic deploying of the retractable ladder are achieved through gravity, without assistance of a motorized apparatus, after the release of safety latches. The automatic closing of the access panel and the automatic stowing of the retractable ladder are achieved through a single motorized apparatus. The latching of the access panel in its closed position is achieved automatically and mechanically. 2. Description of the Related Art Ladders for attic access are widely used by the people in their private homes. Attic accesses are usually provided above the garages and/or living quarters of private homes. The most common attic access consists of an access panel, spring loaded in the closed position and hinged on a wooden structure frame surrounding an opening in the ceiling and installed in the ceiling. To get access to the attic, a user would pull on a piece of rope attached to -the panel and hanging therefrom. This opens the panel, giving access to a folded ladder. The ladder is usually composed of three sections that are folded on top of each other and hinged between each other. The first section is attached to the panel. To deploy the ladder, a user needs to manually grasp the folded second and third sections, rotates this assembly to the deployed position and finally grasp the third section to manually unfold it from the second section. Once the unfolding is achieved, the three sections of the ladder are usually extended in alignment enabling a user to access the attic space. The opposite process needs to be followed by the user for the refolding of the ladder. For re-closing the panel, the user needs to push firmly on the panel moving the panel up to a couple of inches from the ceiling. At such point the springs of the panel take over and move the panel to its fully closed position. The experience shows that the drawbacks of these attic access systems reside in the difficulty of the steps that need to be performed for the opening of the panel, i.e., the unfolding of the ladder, the refolding of the ladder and the re-closing of the panel. While the procedure appears to be easy for a male, provided he is tall, strong and not impaired, the procedure is difficult for a female and virtually impossible as well as potentially dangerous to any elderly person. U.S. Pat. No. 6,866,118 describes a ladder that can be extended and retracted by an electric motor. While the technology described appears to be an improvement over the manual attic ladders mentioned previously, its complexity makes it impracticable and too costly for industrial or private home applications. It would consequently be of great advantage to provide a system giving easy and safe attic access to everyone at a low cost. BRIEF SUMMARY OF THE INVENTION The present invention overcomes the drawbacks of the prior art by providing a fully automatic access to an attic. More particularly, the invention is composed of an access panel that is hinged towards the forward end of a frame structure that supports sections of ladders. The frame structure supports in its aft end part of the mechanism that unlatches the panel, controls its opening, controls the deployment of the sections of ladders, retracts the ladder and closes the panel and re-latches it on the fixed frame. More particularly, while the invention uses gravity for the opening of the panel and for the extension of the sections of ladders, it uses a single electric motor mounted at the aft end of the framing structure for performing the retraction of the ladders and the closing of the panel. The relatching of the panel and its associated sections of ladders in the stowed position is purely mechanical, i.e., without the assistance of electric energy. The stow latch performs the function of maintaining the panel and its associated sections of ladders in the closed position. The safety latch performs the function of controlling the opening of the panel and the extension of the sections of ladders to the ground. The single electric motor performs two distinct functions. The first function is to retract the sections of ladders to their stowed position after they have been extended to the ground, and the second function is to close the panel. In one exemplary embodiment of the invention, there is one electric solenoid for controlling the unlatching of the stow latch and one electric solenoid for controlling the unlatching of the safety latch. Both latches are equipped with a manual override. In another embodiment of the invention, the unlatching of both latches is only achieved manually. It is a characteristic of this invention that the electric motor is only energized to retract the sections of ladders and to close the panel to its stowed position. The electric motor is not energized to either open the panel, or to extend the sections of ladders, or to maintain the panel in its stowed position. The shaft of the electric motor is equipped with a gear that drives a single gear free-wheel. The single gear free-wheel is free to rotate in one direction and is driven by the electric motor in the opposite direction. The single gear free-wheel is mechanically connected to two concentric shafts, the inner shaft being supported by the framing structure while the outer shaft supports one spool on each end thereof. The outer shaft is free to rotate in one direction and is driven by the electric motor in the opposite direction. One end of the cables is rolled up on, and attached to, each of the spools. The other extremity of the cables is attached to the last section of the ladder. In the free direction of rotation of the outer shaft, the spools unroll their dedicated cables allowing the opening of the access panel and subsequently the deployment of the sections of ladders. In the other direction of rotation of the shaft, the spools roll up the cables allowing the retraction of the sections of ladders and lastly the closing of the access panel. In one embodiment of the invention there is an automatic mechanical locking of the access panel in its fully opened position, once the sections of ladders have departed from their fully retracted position. This is to require the re-stowing of the ladder before the closing of the panel. In another embodiment of the invention, there is no mechanical locking of the access panel in its fully opened position. The ladder of the invention is at least composed of two distinct sections that are engaged in a sliding arrangement. Depending of the height of the ceiling, the number of sections can be increased. The figures accompanying the detailed description of the invention show three sections of ladders. The first ladder section is mechanically attached to the access panel, the second ladder section is arranged to slide on top of the first ladder section, and the third ladder section is arranged to slide on top of the second ladder section. Mechanical stops are provided on each of the ladder sections for limiting the sliding stroke. The invention, in accordance with preferred and exemplary embodiments, together with further objects and advantages thereof, is more particularly described in the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an access panel shown in its stowed position; FIG. 2 is a perspective view of the access panel shown in FIG. 1 with the framing structure removed; FIG. 3 is a perspective view of the framing structure equipped with a driving mechanism; FIG. 4 is an enlarged partial perspective view of the rear portion of the framing structure shown in FIG. 3 and the driving mechanism; FIG. 4 a is an enlarged perspective view of a portion of the apparatus shown in FIG. 4 for unrolling and rolling the cables; FIG. 4 b is an enlarged partial perspective view of the brake shown in FIG. 4 ; FIG. 5 is an enlarged perspective view of the stow latch of the apparatus in the latched and stowed position; FIG. 6 is a side view of the access panel shown in the opened position, with sections of the ladder being retracted, hidden items being shown in dotted lines; FIG. 7 is a side view of the access panel showing full extension of section 2 and partial extension of section 3 , with the access panel being locked in its opened position; FIG. 8 shows a perspective view of the access panel in its fully extended position; FIG. 9 shows perspective view of the first ladder section; FIG. 10 shows a perspective view of the second ladder section; FIG. 11 shows a perspective view of the third ladder section; and FIG. 12 is a partial perspective view of the first ladder section and the cover of the access panel; FIG. 13 is a partial side view of a different braking system with the ladder section removed and the access panel being closed; and FIG. 14 is a partial side view of FIG. 13 with the ladder sections removed and the access panel being open. DETAILED DESCRIPTION OF THE INVENTION In the following detailed description, reference is made to the accompanying drawings, which form a part hereof and are shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It is understood that other embodiments may be utilized without departing from the spirit or scope of the invention. To avoid detail not necessary to enable those skilled in the art to practice the invention, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims. With reference to FIG. 1 , the ladder sections 500 , 600 , 700 of access panel 30 are shown in their retracted and stowed position. The ladder sections 500 , 600 , 700 are mounted on a frame structure 10 . With reference to FIG. 2 where the framing structure 10 is removed for clarity, the first ladder section 500 is spaced away from the inner surface 810 of the cover 800 (See FIG. 12 ). Beams 801 are mechanically attached to the cover 800 . In this manner, the climbing of the steps of ladder 500 is not affected by the presence of the cover 800 . In other words, the resting position of the feet of the user of the ladder portions of the access panel 30 remains the same whether the user is on ladder sections 700 , 600 or 500 . This allows each step of the ladder sections to have the same depth, and this provides to the user the same position of steps against his feet regardless of which section of the ladder he is standing on. There are many manual retractable ladders that are commonly used in the industry, and more particularly in the construction industry. These ladders are composed of different sections that are arranged to slide on one another so that they can be extended and retracted. However the steps of these ladders are usually composed of a plurality of rungs. Such a step configuration would be neither comfortable nor safe for everyone to use. Therefore, as shown on FIGS. 2 , 9 , 6 , 7 , 8 , 9 , 10 , 11 , and 12 , all the steps have a comfortable width for the security of the person climbing of each of the sections. With reference to FIG. 2 the ladder sections 500 , 600 , 700 are configured to allow a longitudinal sliding motion between each other. Section 500 is mechanically attached to cover 800 and spaced from it by beams 801 . Section 600 is configured to slide longitudinally on top of, but inside, section 500 . Section 700 is configured to slide longitudinally on top of, but outside, section 600 . No further description of the sliding arrangement is made as this is a very well known and used in industrial ladders technology. Cover 800 that supports the ladder sections 500 , 600 , 700 is hinged via hinge 819 on forward end 13 of the framing structure 10 (See FIGS. 1 and 2 ). Since ladder section 500 is mechanically attached to cover 800 , the hinge 819 can alternatively be installed between ladder section 500 and forward end 13 of framing structure 10 . Still in reference to FIG. 2 , one end of cables 50 is attached to reels 101 while their other end is attached to bars 703 of ladder section 700 . Cables 50 are guided by pulleys 301 hinged on the framing structure 10 (See FIG. 1 ), the pulleys 303 hinged on cover 800 and pulleys 305 hinged on ladder section 500 . Clevis supports 304 of pulleys 303 are located such that the portion of the cables 50 that is guided by pulleys 301 and 303 is substantially vertical. This decreases the force required for the closing of the cover 800 . Pulleys 305 are supported by clevis fittings 306 that are mechanically attached to either the forward portion of ladder section 500 or the forward portion of the cover 800 . Retainer cables 60 have one end attached to bolts 19 that are mechanically attached to longitudinal sides 11 and 12 of framing support 10 (See FIG. 3 ). The other end of cables 60 is hinged on clevis fitting 802 that is mechanically attached to the cover 800 . Still in reference to FIG. 2 , the locks 201 have been moved away from their locked position by the rod 704 that is mechanically attached to ladder section 700 . The locks 201 are spring loaded via springs 202 towards their locked position, and their function is to lock the cover 800 to its full opened position when the ladder sections 600 and/or 700 have moved away from their retracted position. With reference to FIG. 3 , the framing structure 10 that supports the ladder sections 500 , 600 , 700 has a forward end 13 , a intermediate distal end 14 and an aft end 15 . The three ends 13 , 14 , 15 are bordered by two identical longitudinal opposite sides 11 and 12 . There is a central through opening 17 disposed between the forward end 13 and intermediate distal end 14 and the longitudinal sides 11 and 12 . There is no central through opening between intermediate distal end 14 and aft end 15 and the longitudinal sides 11 and 12 ; however, there is a cavity 20 that has a floor 16 . This cavity 20 houses the latching system (as will be subsequently described), the safety system and the driving mechanism 100 of the apparatus of the invention. Still in reference to FIG. 3 , the forward end 13 provides the support for locks 201 , the function of which is described later. The longitudinal sides 11 and 12 support the driving shafts of the braking system 102 , the devices 302 which support pulleys 301 , and the bolts 19 of the retainer cables 60 ( FIG. 2 ). The lower faces of the longitudinal walls 11 and 12 and of the forward end 13 and intermediate distal end 14 are fitted with a seal 18 that is sandwiched by cover 800 when in its closed position. In this manner, should the access panel 30 be installed in a ceiling of a room that has a atmospheric controlled environment, energy spending is minimized. With reference to FIG. 6 , the cover 800 is shown in its full opened position. Cover 800 cannot open further because it is retained by cables 60 . Pulled by springs 202 , the mechanical locks 201 have started to pivot on mounting devices 203 that are mechanically attached to forward end 13 . One end 205 of the springs 202 is attached to the locks 201 while the other end 206 is attached to rod 503 of ladder section 500 (See FIG. 9 ). In this position the mechanical locks 201 have hot yet reached their latched position because the ladder section 700 has not moved away from its retracted position. With reference to FIG. 7 , the mechanical locks 201 are pulled by springs 202 and have reached their latched position. The mechanical locks 201 are resting on their abutment fitting 204 that is mechanically attached to the forward end 13 . The mechanical locks 201 are also resting on fittings 501 (See FIG. 9 ). In this position, the cover 800 and the ladder sections 500 , 600 , 700 are locked in the opened position because of the over center arrangement of the mechanical locks 201 . Also in this position, the reaction force that the ladder section 500 communicates to the mechanical locks 201 is to further rotate the mechanical locks 201 towards an even more secure locked position, but this not possible as the abutment fittings 204 prevent the mechanical locks 201 from rotating further. In reference to FIG. 8 , the ladder sections 600 and 700 are fully extended. Cables 60 prevent further opening of cover 800 . Operation of cables 50 with pulleys 301 , 303 and 305 and reels 101 retract the ladder sections 600 and 700 and close the cover 800 as will be described hereinbelow. Starting with FIG. 1 , the access panel 30 is retracted and closed or stowed. To initiate the opening of the cover 800 of the access panel 30 , one needs to press a switch in the living area (not shown) for energizing of the solenoid 223 that has its piston rod spring loaded in the retracted position (See FIG. 5 ). This action extends the piston rod of the solenoid 223 which then pivots the unlatching lever 221 of stow latch 225 towards its unlatched position. The unlatch lever 221 disengages stow latch 225 from its latch receptacle 220 mounted on the intermediate distal end 14 of the framing structure 10 , and by gravity the cover 800 moves away from its latched position, but is stopped by the safety latch 211 that engages teeth of latch wheel 210 , which is mechanically attached to one of the reels 101 (See FIG. 4 ). Energizing the solenoid 213 retracts its piston rod which pivots the safety lever 211 around its axis that is supported by clevis fitting 212 . The piston rod of solenoid 213 is spring loaded in the extended position. Therefore, energization of the solenoid 213 must be maintained for the safety latch 211 to disengaged from the teeth of the wheel 210 . The switch (not shown) that energized the solenoid 213 is a not an ON-OFF switch, but a switch that needs to be pressed and maintained pressed by the user to open the cover 800 and lower ladder sections 600 and 700 . This is a safety characteristic of the invention, as the access panel 30 cannot accidentally fully open and fully extend unless the user has decided to do so. For example, this prevents the full opening of the access panel 30 and extension of the ladder sections 600 and 700 , should solenoid 223 be accidentally energized by a child or anyone else or should the stow latch 225 break. In the event of an electrical failure, the stow latch 225 can be manually released by pulling on rope or chain 151 that goes through the floor 16 of the framing structure 10 (See FIGS. 3 , 4 , 5 and 6 ). Safety latch 211 can be manually released by pulling on rope or chain 152 (See FIGS. 4 and 6 ). Once stow latch 225 is released and safety latch 211 is kept away from engaging the teeth of latch wheel 210 , by gravity only, without energizing motor 109 , the cover 800 and the ladder sections 500 , 600 , 700 keep on opening until the access panel 30 is fully opened to the position shown in FIG. 6 is reached. During this phase of the opening, it is gravity only that unrolls the cables 50 from their reels 101 . Cover 800 has cables 60 to limit the opening of the panel access 30 to a predetermined angle typically ranging between 60 and 70 degrees. Still in reference to FIG. 6 , mechanical locks 201 are pulled by their associated springs 202 that force the mechanical locks 201 to rotate around the pivoting axis of mounting devices 203 attached to forward end 13 of framing structure 10 . The pivoting of mechanical lock 201 is also guided and limited by rods 704 attached to ladder section 700 (See FIGS. 6 and 11 ). In the position shown in FIG. 6 , the mechanical locks 201 have not reached their locked position because they are still resting on rods 704 and are not resting on fittings 501 of ladder section 500 . Gravity effect on ladder sections 600 and 700 continues to unroll cables 50 from reels 101 until the ladder sections 600 and 700 reach the position shown in FIG. 7 . The stops 603 of ladder section 600 (See FIG. 10 ) rest on step 740 of ladder section 700 , so that when ladder section 700 is extending from the position of FIG. 6 to the position shown in FIG. 7 , ladder section 600 follows in unison with ladder section 700 . In the position of FIG. 7 , the stops 602 of ladder section 600 (See FIG. 10 ) rest on the stops 502 of ladder section 500 (See FIG. 9 ) and, consequently, ladder section 600 has reached its fully extended position. As is also shown in FIG. 7 , the mechanical locks 201 are no longer resting on rods 704 of ladder section 700 as mechanical locks 201 are pulled by associated springs 202 to their fully locked position. Mechanical locks 201 are now resting on fittings 501 of ladder section 500 (See FIG. 9 ) and on abutment fittings 204 . In this position the cover 800 and its associated ladder sections 500 , 600 and 700 are locked open and cannot be closed. Gravity effect of ladder section 700 continues to unroll cables 50 from their reels 101 until stops 702 reach stops 604 of ladder section 600 (See FIG. 10 ). In this position the ladder sections 500 , 600 and 700 have reached their fully extended position shown in FIG. 8 . In order to slow down the speed of opening of the cover 800 , and the speed of extension of the ladder sections 500 , 600 and 700 , a braking system 102 is installed on one of the reels 101 as will be described hereinbelow. In reference to FIGS. 4 and 4 b the longitudinal wall 12 of framing structure 10 is equipped with a braking system 102 that slows down the rotational speed of the reels 101 when the reels 101 unroll the cables 50 for the opening of the cover 800 and the extension of the ladder sections 500 , 600 , 700 . The braking system 102 consists of a free wheel 162 whose inner shaft 153 is part of a flange 161 that is mechanically attached to side wall 12 . The free wheel 162 supports a braking disk 163 . The free wheel 162 is mounted such that it is not free to turn when the free wheel 110 is free to turn i.e., when the free wheel 110 is allowing the reels 101 to unroll the cables 50 . In other words the free wheel 162 of the braking system 102 of the reels 101 is mounted in the opposite way compared to the free wheel 110 . The friction force of reel 101 against braking disc 163 is adjusted through nuts 105 (See FIG. 4 ). As shown in FIGS. 8 and 11 , ladder section 700 is equipped with adjustable legs 730 , fitted with rotating shoes 731 to ensure perfect contact with the ground when the ladder sections are fully extended. As previously described, the opening of the cover 800 and the extending of the ladder sections 500 , 600 , 700 is only achieved through gravity. The retraction of the ladder sections 500 , 600 , 700 and the closing of the cover 800 is achieved via the assistance of a motor. Starting from the position shown in FIG. 8 , the motor 109 shown in FIGS. 4 and 5 is energized via a switch (not shown) in the living area that closes the circuit of the electrical connections of the motor 109 to an electrical power source (not shown). A mechanical device 150 is connected to the motor 109 . No further description of this is provided as this is very well known in the art. Pinion 108 mounted on the shaft of the motor 109 drives a chain 107 that, is connected to a single gear free wheel 110 . A single gear free wheel 110 is driven by the chain 107 in only one direction of rotation, but is free to rotate in the opposite direction to unroll the cables 50 . The driven rotation of single gear free wheel 110 corresponds to rolling cables 50 on their respective reels 101 . As shown in FIGS. 4 and 4 a one of reels 101 is connected to the single gear free wheel 110 via a plurality of fixed rods 11 1 , while the other reel 101 is connected to single gear free wheel 110 via a plurality of adjustable rods 103 and 104 , the adjustment being carried out through nuts 105 . The single gear free wheel 110 is mechanically attached to a center shaft 106 that is supported by the longitudinal walls 11 and 12 of the framing structure 10 . The motorized drive of the single gear free wheel 110 in the direction of rolling up the cables 50 on their respective reels 101 continues until the ladder section 700 reaches the position shown in FIG. 7 . At such point, step 740 of ladder section 700 (See FIG. 11 ) meets with stops 603 of ladder section 600 (See FIG. 10 ). Thereafter, further reeling in of cables 50 further retracts ladder section 700 and pulls with it ladder section 600 towards their retracted position. When ladder section 700 approaches its fully retracted position, its rods 704 meet with locks 201 and drives locks 201 towards the unlatched position. At such point as the position shown in FIG. 6 is reached, the ladder sections 500 , 600 , 700 are fully retracted, but the cover 800 is unlatched and ready to be closed by the further rolling up of the cables 50 on their reels 101 to reach the closed position. When the cover 800 is approaching the closed position, stow latch 225 , via spring 224 , meets its latch receptacle 220 (See FIG. 5 ) forcing stow latch 225 to re-latch. During the complete rolling up sequence of the cables 50 , the teeth of the latch wheel 210 rotate the safety latch 211 away from its latching position (See FIG. 4 ). Once the access panel 30 is fully re-latched, it is in the configuration shown on FIGS. 1 and 2 and the electric motor is automatically de-energized, via known means such as electrical load currents for example. During the complete retraction of the ladder sections 500 , 600 , 700 and the closing of the cover 800 , the braking system 102 offers no resistance as it is free to rotate in the direction of rolling up the cables 50 . In reference to FIGS. 9 , 10 , and 11 ladder sections 500 , 600 , 700 are respectively fitted with a series of steps 520 , 620 , 720 that provides comfort and safety to the user. For instance the steps 520 , 620 , 720 may be covered with a non slippery surface. In addition for ease of climbing, ladder sections 500 , 600 are respectively fitted with railing 505 , 605 (See FIGS. 9 and 10 ). The invention uses only the motor 109 to retract the ladder sections 500 , 600 , 700 and close the cover 800 . Only gravity is used to open the cover 800 of access panel 30 and extend the ladder sections 500 , 600 , 700 as previously described. FIG. 13 shows the cover 800 on which the ladder sections 500 , 600 , 700 (not shown for clarity) are mechanically attached and in their stored position adjacent longitudinal side 1 l. Longitudinal side 11 is equipped with at least one off center pivoting cam 1010 on axis 1020 and a fixed cam 1000 . Pivoting cam 1010 can either take the off center position shown in FIG. 13 , or the off center position shown on FIG. 14 . The cable 50 , through the weight of the cover 800 and ladder sections 500 , 600 , 700 , produces counter clockwise pivoting motion MI that forces off center pivoting cam 1010 to stay in its position shown in FIG. 13 . Cable 50 is free, i.e., not squeezed between off center pivoting cam 1010 and fixed cam 1000 . In FIG. 14 , the ladder sections 500 , 600 , 700 have started their deployment and cable 50 , through gravity, produces clockwise pivoting motion M 2 to the off center pivoting cam 1010 which makes it rotate around axis 1020 and, consequently, applies a braking pressure force to said cable 50 against the fixed cam 1000 . Gravity feed is consequently slowed down by the braking pressure force on cable 50 between off center pivoting cam 1010 and fixed cam 1020 . This arrangement shown and described in connection with FIGS. 13 and 14 has the benefit to easily control the speed of opening of the ladder sections 500 , 600 and 700 and their fall to the ground. It can be used as a stand alone, or in combination with the devices that control the lowering down of the ladder to the ground.

An access panel is shown in the present invention to provide easy and safe access to an attic space or elevated structure. The access panel is fully automatic. During opening, the access panel only uses gravitational forces for opening a cover. Only during closing is the access panel motorized. The gravitational forces are used to both open the cover and extend the ladder sections, while the motor is only used to retract the latter sections and close the cover. A stow latch keeps the cover closed during non-use. A safety switch keeps the access panel from accidentally opening and the ladder sections from lowering if the stow latch is released. A mechanical lock keeps the cover open when the ladder sections have been lowered.

You are an expert at summarizing long articles. Proceed to summarize the following text: RELATED APPLICATION This is continuation-in-part of U.S. Ser. No. 10/170,273, filed Jun. 11, 2002, now abandoned which is a continuation-in-part of U.S. Ser. No. 10/010,376, filed Dec. 6, 2001. FIELD OF THE INVENTION The present invention concerns improvements in and relating to insect/fly screens for mounting over door and window openings. BACKGROUND TO THE INVENTION Whereas there are currently commercially available a number of different designs of insect/fly screens that are adapted to mount over door and window openings, many of these are hinged to the surround of the opening and are not optimally convenient in use. More sophisticated fly screen systems have become available in recent years and which are designed to slide on tracks across a door or window opening. As a generality, however, these are formed with a bulky, rigid frame defining the tracks as well as a comparatively bulky and rigid frame of the flyscreen itself. It is a general object of the present invention to provide a comparatively slim, compact and economical flyscreen installation and which is reliably effective and may be adapted to suit a number of different types of door and window configuration. SUMMARY OF THE INVENTION According to a first aspect of the present invention there is provided an improved flyscreen to be slidingly deployed across an opening of window or door, the window or door having a static glazing pane or panel and an opening pane or panel, the flyscreen comprising a frame dimensioned to correspond to the dimensions of the window or door opening to be covered by the flyscreen and having a mesh screen therein extending thereacross, the frame having a brush or filamentous pad strip extending substantially the full height of an upright of the frame and which when the screen is slidingly mounted adjacent to a window or door to be slidingly moved back and forth across the opening of the window or door, is substantially able to brush over the surface of the static pane or panel of the window or door. Advantageously the flyscreen is installed to a window or door and wherein the upright/jamb of the window or door which defines one side of the opening of the window or door against which the trailing edge upright of the flyscreen frame comes to rest when the screen is drawn to overlie the opening has a mating brush or filamentous pad strip thereon extending at least substantially the length thereof to co-operatively engage/abutt against the brush or filamentous pad strip of the frame to substantially seal the edge of that frame against ingress by any insects. Suitably one or more further brushes or filamentous pad strips are provided extending vertically and/or horizontally of the flyscreen frame and particularly preferably there is a vertically extending brush or filamentous pad strip on the trailing edge upright of the frame. Preferably the fly screen is adapted to mount to a sliding window or door having a handle that projects substantially from the plane of the window or door, wherein the brush or filamentous pad strip on the frame is provided on a projecting limb of the frame that projects from the frame toward the plane of the door or window static pane, allowing the mesh screen to clear the door or window handle but ensure that the brush or filamentous pad strip remains closed or brushes over the surface of the door or window static pane as the frame is slid back and forth. Preferably the projecting limb is adapted to be demountable from the frame. Advantageously a plurality of interchangeable projecting limbs are provided of differing projection extents to suit different extents of projection of the door or window handles. Suitably a brush or filamentous pad strip is provided extending along substantially the full length of the top edge of the frame. Preferably a brush or filamentous pad strip is provided extending along substantially the full length of the bottom edge of the frame. Suitably a brush or filamentous pad strip is provided extending along the top edge and/or bottom edge of the projecting limb of the frame. According to a second aspect of the present invention there is provided an improved flyscreen to be slidingly deployed across the opening of a window or door and being of horizontal roller screen type having a mesh flyscreen on a roller that is mounted, in use, to a top, bottom or side of a door or window opening to be drawn across the opening, the flyscreen assembly further comprising a pair of guide rails extending in use opposite to each other to guide the opposing side edges of the screen as it is extended, wherein at least one and suitably both of the guide rails has a brush extending therealong substantially the length thereof and is/are provided with an adjustable stabiliser/gripping bar extending therealong substantially the length thereof to grip and stabilise the screen against the brush(es) to counter sag and/or disturbance by the wind or other disruptive forces. Preferably the stabilising/gripping bars are provided with Velcro™ or other fastening means to fasten to the edge of the mesh screen, gripping the screen in place. Advantageously the roller blind is arranged to extend in a substantially vertical direction and the screen is extended or retracted by a drawstring. Preferably the screen is arranged vertically and the leading edge of the screen has a bar extending thereacross which is weighted to facilitate stable deployment of the screen. Advantageously the roll of the roller blind is held in a roller cassette and wherein the cassette is provided with two rows of brush means, one inward of the other relative to the opening of the roller cassette from which the screen is drawn, whereby the second row of brush means acts as a secondary barrier against ingress of flies. BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, wherein FIGS. 1A and 1B are, respectively, front and rear elevation views of a first embodiment of flyscreen, to be mounted on tracks to slide across a door opening in a set of French windows; FIGS. 1C, 1 D and 1 E are, respectively, rear perspective, front elevation and front perspective views of a detail of the screen's leading stile; FIG. 2 is a plan view of the flyscreen of the first embodiment from above; FIG. 3 is an end elevation view of the leading end of the flyscreen; and FIG. 4 is an enlarged fragmentary view of the same; FIGS. 5 and 6A are, respectively, an enlarged fragmentary plan view of the screen as seen in FIG. 2, and a horizontal sectional view of the same; FIGS. 6B and 6C are, respectively, an enlarged fragmentary plan view of the FIG. 1C version of screen (having the upright strengthening bars and with a preferred alternative configuration of channel on the door jamb) at the right of the doorway, and a similar enlarged fragmentary plan view of the screen moved to the stowed position at the left of the doorway; FIG. 7 is a perspective view of a version of the screen mounted to french doors i.e. glazed hinged doors; FIGS. 8A and 8B are, respectively, front and rear elevation views of the second preferred embodiment of the present invention suitable for use with windows; FIG. 8C is an end elevation view of the second preferred embodiment of fly screen; FIG. 9 is a plan view of the second preferred embodiment from above and FIG. 9A is an enlarged fragmentary view of the dovetail mounting of the projecting limb to the fly screen frame in FIG. 9; FIG. 10A is a frontal perspective view of a version of the second preferred embodiment (having a simplified profile of extension) and showing the close or brushing passage of the screen's trailing edge brush over a window to which it is mounted, and FIG. 10B is a corresponding fragmentary view of an alternative version of the trailing edge brush which is fore-shortened and arranged to cooperate with a brush on the static stile of the window; FIGS. 11A to 11 D are, respectively, a frontal perspective view of a first further version of the second preferred embodiment of fly screen, a rear perspective view of a second further version (for a window that opens to the right), a rear perspective view of a third further version (for a window that opens to the left or right), and a rear perspective view of a fourth further version (same as third further version but with extra transverse brush on cross-bar); FIG. 11E is a plan view of the fourth further version mounted to a window; FIG. 12A is a front elevation view of a third preferred embodiment of the invention, comprising a flyscreen of roller screen type; FIG. 12B is an end elevation view of the FIG. 12A embodiment; FIG. 12C is a fragmentary view of a track and stabilising/gripping bar as viewed from the left hand side at detail A in FIG. 12A; FIGS. 13A and 13B are, respectively, fragmentary plan views from above of the details shown in FIG. 12 C and showing the stabilising/gripping bar partially released and in locking engaged state, respectively; and FIGS. 14A, 14 B and 14 C are, respectively, a front elevation view of the third embodiment showing covers concealing the upright tracks and with the screen raised, a transverse sectional view through the roller screen top casing/roller cassette, and a frontal view of the secondary brush component thereof. DESCRIPTION OF THE PREFERRED EMBODIMENTS As illustrated in FIGS. 1 to 6 , the first embodiment of the insect screen is suitable for use with French windows (glazed sliding doors) and may also be used as a sun screen. It comprises a mesh sheet 1 held substantially taut within a rectangular frame 2 a-d . This is of a size and shape that corresponds to the size and shape of the French windows or other sliding door installation against which it is adapted to sit. The frame 2 a-d mounts within an additional channel retro-fitted to or integral with the track of the sliding French window in order to be able to slide across the door opening when the French window/door is slid back to its opened state. The mesh of the mesh sheet 1 is suitably sufficiently fine to exclude the smallest of flying insect pests such as gnats and mosquitoes. It is suitably of a plastics polymer such as nylon—in which case horizontal strengthening bars 3 are suitably provided at intervals, which are suitably equal intervals but which may be asymmetric, of the height of the screen and extending across the width of the screen. However, where the mesh is formed of a substantially rigid material such as aluminium or other metal or metal alloy, such additional strengthening is generally unnecessary other than, if desired, to act as a clear visual warning that the screen is drawn across the door opening to prevent individuals from failing to notice the fine unobtrusive screen and walking into it. As can be seen from the side elevation, the insect screen has an extremely slim profile which is in practice suitably of the order of 20 mm or less and generally of the order of 16 mm (this is the depth of the screen, ie as measured from the front face of the screen to the back). The rectangular frame 2 a-d is suitably formed of a pair of uprights/stiles 2 a , 2 b and top and bottom opposing cross-bars 2 c , 2 d all of aluminium, hard, hardened or strengthened plastics, wood or other suitable material that is lightweight but reasonably rigid. In one preferred construction, as can best be seen in FIGS. 1C and 1E, the stiles 2 a,b and cross-bars 2 c,d are suitably relatively thin planks being of the order of only 8 mm deep but the stiles 2 a,b are each re-inforced with a strengthening plank/bar/protrusion 11 that is suitably of the order of a further 8 mm in depth, whereby the profile of the screen is the preferred 16 mm as mentioned above. The trailing edge stile 2 a of the frame has a vertically extending brush 4 (preferably bristle brush) which is adapted to ride smoothly over the surface of the underlying static glazing pane 100 of the French windows without damage to the glass if the screen should be pressed against the glass. It co-operatively engages (FIG. 6A) with a corresponding vertically extending brush 5 that is mounted on the static stile 6 of the French windows that borders the door opening opposite the jamb 8 . Abutment of the vertical brush 4 of the trailing edge stile 2 a of the screen frame against the vertical brush of the static stile 6 gives a firm and insect tight closure of the door opening when the screen is drawn across the opening. A small ramp 15 provided on the static stile 6 adjacent to and leading up to the vertically extending brush 5 serves to guide the vertical brush 4 of the screen's trailing edge stile 2 a slightly away from the plane of the window as it moves into engagement with the brush 5 , the screen thereby being itself pushed slightly away from the plane of the window and so partially wedged against its top and bottom tracks The leading edge of the leading stile 2 b of the screen illustrated in FIG. 6A has a lip 7 which sits closely against a rail/channel 8 b on the right door jamb 8 to close against that end of the door opening. Suitably there is a rail/channel 8 b at both right and left ends of the door opening. Each of the top and bottom cross-bars 2 c , 2 d has their own respective brush 9 , 10 extending horizontally the length thereof to seal the screen respectively from top and bottom. The illustrated configuration of fly screen has a pair of small handle knobs 10 provided on the lower of the transverse strengthening bars 3 , one knob 10 at each end. A small stowable handle is suitably provided on the rear face of the screen for handling the screen from the outside. This is suitably provided on the transverse bar 3 or on the leading edge stile 2 b and is particularly suitably pivotable to collapse substantially flat against the screen so that when the screen is fully drawn back against the static pane of the French windows the screen lies very closely against the static pane of the French windows. Such a pivotable handle 12 is illustrated in FIGS. 1C to 1 E as comprising a ring 12 that is pivotally mounted to the horizontal strengthening bar 3 by a bearing 13 . As also shown in FIG. 1C, a spacer pad 14 is suitably provided at least adjacent to and suitably either side of the pivotal handle 12 primarily to counter risk of the stowed handle contacting the window, but also spacing the cross bar 3 away from direct contact with the window. In the preferred embodiment the pivotal handle is magnetic such as to be magnetically attracted back to its stowed position closely adjacent the screen. By way of further detail apparent in the figures, the screen is provided with triangular corner pieces at each corner of the frame to better hold the mesh of the screen in place within the frame. Turning to FIG. 6B, this shows the FIG. 1C version of the screen as pulled to the doorway-closing position. Here the closure rail 8 b on the door jamb 8 has a distinct channel-defining shape to ensure that the leading edge 2 b of the closed screen is constrained closely against the jamb 8 . A felt brush spacer pad 16 is further provided in that rail 8 b to enhance the security of fit of the screen in the channel/rail 8 b. Turning to FIG. 6C, this shows the screen pulled to the stowed position to the left of the doorway. Here there is a corresponding channel-shaped rail 8 b′. With reference to FIG. 7, the illustrated flyscreen for french doors has generally the same construction as the screen for french windows, including having the vertical brush/strip on the trailing edge stile and suitably also on the leading edge stile with the trailing edge one co-operating with a corresponding vertical brush on a central stile of the french doors. One or a pair of such flyscreens may be used with double doors. A second embodiment of the invention, comprising a fly screen for windows, is illustrated in FIGS. 8 A through to 11 E and has a rigid rectangular frame construction in common with the first aspect The materials and construction are suitably generally the same. The slim construction of the screen frame is again suitably augmented by an upright strengthening bar 22 on the leading stile 2 b ′. However, the trailing edge stile 2 a ′ of the fly screen frame 2 a ′- 2 d ′ is provided with an extension profile 20 that carries the brush 4 ′ of the trailing end of the frame and which is dimensioned suitably to enable the brush 4 ′ to maintain continuous contact with the underlying window while giving the fly screen clearance of the window handle. The depth of the extension 20 is suitably adapted to suit the required clearance. In a particularly preferred embodiment the extension profile 20 is demountable from the fly screen trailing edge stile 2 a ′ to enable selection of the appropriate depth of extension 20 from amongst alternatives. The extension profile suitably keys to the frame by a sliding dovetail arrangement 21 or other keying arrangement (FIG. 9 A). As can be seen from FIG. 9, a channel 23 is suitably provided at one or both ends of the window opening, again to assist in constraining the screen closely in place when drawn or retracted. Suitably again, the screen runs along tracks 24 in the top and/or bottom (FIG. 10A) of the window opening—preferably both. Brushes 9 ′ are suitably provided not only along the top and bottom bars 2 c ′, 2 d ′ of the screen frame and the profile extension 20 of the trailing edge but optionally also along the leading edge. Where a brush is provided down the leading edge 2 b ′ this is suitably a felt brush rather than a bristle brush in contrast to the others. Various preferred configurations of brush are shown in FIGS. 11A to 11 D As in the embodiment of FIGS. 1 to 6 , the brush 4 ′ will suitably abut/engage with a corresponding brush 5 ′ on an upright of the sliding window when the screen 1 ′ is fully extended across the window opening. Referring to FIG. 10B, the profile extension 20 may be made somewhat shorter than to cover the gap between screen and window when the corresponding brush 5 ′ on the upright is provided and is made taller, ie to project farther out from the plane of the window to meet with the shorter extension 20 . Turning now to FIGS. 12 to 14 , these illustrate a roller blind-like insect screen which has a mesh sheet 1 ″ on a roll that may be pulled downwardly with its opposing lateral edges running in a pair of upright U-shaped channel tracks 30 , each of which tracks 30 is preferably encased in a cover 36 (FIG. 14 A). It may optionally also have a corresponding bottom track (not shown). It is preferably cord adjustable for deployment, since a spring-loaded gravity drop mechanism is unreliable. The bottom bar 31 of the screen is suitably weighted with lead weights or the like to give stability and provide balance from front to back of the bar 31 . A handle knob 46 is provided mid-way along the bar 31 to facilitate manual manipulation into place. The strength of the screen 1 and support for the weighted bottom bar 31 is enhanced through provision of thickened solid 1 cm edging to the screen 1 . The top casing/roller cassette 40 has a removable front cover 43 and, along the back thereof, a brush 44 extending the length thereof to exclude flies. A removable secondary fly trap is suitably positioned in the top casing/roller cassette 40 of the roller comprising a plastic molding 41 that pivotally hangs by a pivot 47 from the roof of the cassette 40 and extends the length of the roller the molding 41 having a brush 42 running along its length that rests on the screen roll 1 ″ and accordingly remains continuously in contact with the screen roll 1 ″ as the screen is extended or retracted and as the roll 1 ″ correspondingly decreases or increases in diameter. The molding 41 having the brush 42 is suitably pivotally mounted via pivot 47 to the cassette 40 . The upright tracks 30 on either side of the roller screen 1 ″ each have a bristle brush 32 along one longitudinal edge and a stabiliser panel/wing 33 along the opposing longitudinal edge. Each of the wings 33 is adjustably mounted to its track 30 on hinges 34 . The hinges 34 take the form of bent pins being elongate and mounting in slots 35 in the wings 33 so that the wings 33 may be deployed by pulling laterally across and pivoting outwardly to release the edges of the roller blind screen 1 ″ to allow it to be pulled down. The wings 33 are then pivoted back and pushed back into the tracks 30 so that their curved rear faces push into and thereby to grip the fly screen against the brushes 32 in the tracks 30 once the screen is fully drawn down and deployed. A strip of Velcro™ 50 or similar is suitably provided on the rear face of each wing 33 preferably extending substantially along its length to enhance its grip. This gripping of the fly screen once the screen is deployed holds it firmly in place against any gust of wind. In the absence of a bottom track or not, the bottom edge/leading edge of the screen is suitably provided with a short felt brush 45 therealong and which effectively seals against the windowsill.

An improved flyscreen to be slidingly deployed across an opening of window or door, the window or door having a static glazing pane or panel and an opening pane or panel, the flyscreen comprising a frame dimensioned to correspond to the dimensions of the window or door opening to be covered by the flyscreen and having a mesh screen therein extending thereacross, the frame having a brush or filamentous pad strip extending substantially the full height of an upright of the frame and which when the screen is slidingly mounted adjacent to a window or door to be slidingly moved back and forth across the opening of the window or door, is substantially able to brush over the surface of the static pane or panel of the window or door.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION This invention is directed generally to liquid separation within liquid containers such as underground wells and, more particularly, to a method and apparatus for removing substantially immiscible liquids, such as hydrocarbons or pollutants from a collecting well which contains both water and such immiscible liquids. There are various known techniques for removing immiscible liquids (hereinafter generally referred to as "liquids" or "liquid product") from containment apparatus. One such method is to employ a "cone of depression" technique. As stated in U.S. Pat. No. 4,746,423, the use of a "cone of depression" for collecting hydrocarbons from an underground well containing an overlying immiscible liquid, usually a hydro-carbon product, from an underlying, conductive, heavier liquid in a two liquid body is well established. The technique requires a depression pump located at or near the bottom of a well to remove water in large enough quantities to actually lower the water table locally, and thereby cause underground liquids to drain toward the region in which the table is depressed. The lighter liquid products then collect within the well along with the water and typically as the water is pumped out by the depression pump, a skim pump located higher in the well, in the region atop the collected water where the lighter fluid products collect, is used to pump out the contaminants. Several examples of this technique and other removal schemes may be found in the patents listed below. U.S. Pat. No. 4,273,650 to Solomon teaches a system using a cone of depression technique which employs a submergible, drawn down, electrically powered pump submerged at the bottom of a well. A water discharge control including the pump and the pump switch controls the flow of water from the well to establish and maintain by gravity flow a predetermined liquid level at a spaced distance below the static water table. In this way, a cone of depression is established. A combined pollutant pump and sensor apparatus including an electrically powered pollutant pump, a pump switch and sensors responsive to pollutant level to actuate the pump switch are supported in the well at the level of the apex of the cone of depression. The Solomon apparatus also includes sensors for sensing a low level water/pollutant interface and energizing the pollutant pump to pump pollutant into a tank while permitting the water/pollution interface to rise and also for sensing a high level water/pollutant interface and de-energizing the pollutant pump upon sensing the high level water/pollutant interface. U.S. Pat. No. 4,469,170 to Farmer, Jr. teaches a skimmer which is designed to float in the two-liquid body contained in the well. The Farmer, Jr. skimming apparatus requires a float and, apparently, also requires a depression pump. U.S. Pat. No. 4,746,423 to Moyer discloses a two pump skimmer system for recovery of lighter-than-water hydrocarbons from water wells. The pumps are located in individual chambers which are interconnected with the water chamber below the hydrocarbon chamber and with limited one-way flow into the water chamber. Both pumps are independently controlled by sensors in the upper chamber to assure that each pumps only the proper liquid. U.S. Pat. No. 4,766,957 to McIntyre discloses a method and apparatus for gravitationally separating hydrocarbons and water discharged from a subterranean well. McIntyre teaches that a mixture of hydrocarbons and water flows into the interior of a well casing through perforations disposed adjacent the production zone. The water flows downwardly or is forcibly pumped downwardly to the water absorbing formation and is absorbed in such formation. U.S. Pat. No. 4,770,243 to Fouillout, et al. shows a microprocessor controlled system for separating water from hydrocarbons. The Fouillout device is directed to the field of the production of petroleum from deposits in which water is mixed with hydrocarbons, and not to the skimming of contaminant hydrocarbons from a water producing well. Separation of the water from the hydrocarbons is accomplished at the bottom of the well in a packer. U.S. Pat. No. 4,761,225 to Breslin discloses an apparatus for controlling the removal of liquid hydrocarbons from groundwater in a perforated well casing consisting of a plurality of pump chambers and a control system which is powered by compressed air. The present invention has advantages over the prior art in that, it is believed that for the first time, it provides a highly dynamic, automatic microprocessor-controlled system which has a programmable operation capable of using a single sensor in combination with a float sensor to control both a skim pump and a depression pump, thereby promoting cooperation between the two pumps to result in hydrocarbon removal. The invention provides a microprocessor based controller for a "cone of depression" type removal system which heretofore has not been found in the prior art. In yet another aspect of the invention, a method and apparatus is provided to remove floating liquids using only an interface sensor and a microprocessor controlled skim pump, without employing a depression pump to create a cone of depression. SUMMARY OF THE INVENTION The present invention provides a method and apparatus for removing floating, substantially immiscible liquids such as hydrocarbons from containers or wells containing both liquids and water. In one aspect of the invention, a microprocessor control receives and processes input signals from a liquid sensor, an upper water interface sensor and a skim pump. The skim pump is located in the well proximate to the water interface. The liquid sensor is located proximate to the skim pump. The upper water interface sensor is located adjacent to and below the liquid sensor. The microprocessor control is initialized by setting certain parameters such as the initial conditions for pump output values. The microprocessor controls and operates the skim pump in response to the input signals. In a further aspect of the invention, a depression pump is also included. The depression pump is located in the well below the skim pump. In one embodiment of the invention, the skim pump is not activated if the depression pump is running. If the depression pump is not running and liquids are sensed by the liquid sensor at the skim pump, the skim pump is activated. In appropriate applications, the skim pump may be operated so as to be inhibited at all times when the depression pump is operating. In other applications, the skim pump and depression pump may operate simultaneously. Collected water is discharged to a designated site outside of the well by the depression pump. The skim pump pumps liquid products into a product tank located outside of the well. The product tank also provides an input signal to the microprocessor control from a high tank level sensor which provides an indication as to the fluid level in the tank. The microprocessor control processes this signal in order to stop the skim pump in the event that the product tank is filled. In a yet further aspect of the invention, status displays in the form of lights and electronic readouts are provided as well as external problem or troubleshooting outputs. Other optional features may be added, such as a lower water interface sensor, which also provides input signal data to the microprocessor control. It is one object of the invention to provide a microprocessor controlled apparatus for removing hydrocarbons from wells containing both hydrocarbons and water. It is yet another object of the invention to provide a unitary controller which controls both a skim pump and a depression pump using input signals from a single water interface sensor for controlling and coordinating operation of both pumps. It is a further object of the invention to provide a hydrocarbon removal apparatus which operates so as to prevent water from being pumped through the skim pump. It is still a further object of the invention to provide an apparatus for creating a cone of depression removal system which uses signals from a lower water interface sensor to inhibit the depression pump from pumping liquid product. Other objects, features and advantages of the invention will become apparent to those skilled in the art through the description of the preferred embodiment, claims and drawings herein wherein like numerals designate like elements. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of one embodiment of the apparatus of the invention. FIG. 2 is a block diagram of an alternate embodiment of the apparatus of the invention. FIG. 3 is a high level flow chart illustrating generally the method of the invention. FIG. 4 is a detailed flow chart of the control scheme of a depression pump as employed by one embodiment of the invention. FIG. 5 is a detailed flow chart of the control scheme of a skim pump as employed by one embodiment of the invention. FIG. 6 is a block diagram of a further alternative embodiment of the invention employing a modulating valve for regulating water discharge from the depression pump. FIG. 7 is a flow chart of a method of optimizing liquid product removal as provided by the invention. FIG. 8 illustrates an example of a control panel employed by one embodiment of the invention. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, a block diagram of one embodiment of the invention is shown schematically. The liquid product removal apparatus of the invention 10 for a cone of depression scheme comprises a microprocessor control 12, skim pump 14, liquid sensor 22, upper water interface sensor 23, depression pump 16, skim pump power contactor 30, depression pump power contactor 32, skim pump time delay switch 34, and depression pump time delay switch 36. In another aspect, the invention provides an apparatus and method for removal of floating liquids which may be used in a system not requiring a cone of depression technique. In such a system, the basic apparatus needed for hydrocarbon removal is microprocessor control 12, skim pump 14 and liquid sensor 22. In such a system, as long as liquid sensor 22 provided a signal indicating the presence of floating liquid products, the skim pump would be activated by the microprocessor control unit to pump out the liquids. The skim pump time delay switch 34 may still be utilized to prevent short cycling of the skim pump. The microprocessor control may advantageously be any suitable microprocessor device such as an 8 bit microprocessor or similar device. In one embodiment of the invention, an INTEL model 8751 8-bit microprocessor is employed. The microprocessor and associated elements including the contactors and switches are preferably located in a control enclosure or housing 5. Those skilled in the art will appreciate the fact that any number of similar programmable devices, computers or equivalent circuits may also be employed to provide the microprocessor control function. The microprocessor executes a control algorithm according to the invention as described herein. The invention will first be described in terms of its functional elements, followed by a description of the operation of the invention. The skim pump time delay switch 34 may be used to set a first time delay used in operating the skim pump. Similarly, the depression switch 36 may also be set manually or automatically in order to set a second time delay used in the operation of the depression pump. Both timers 35 and 37 are advantageously implemented in the software control algorithm executed by the microprocessor control. The settings of the switches 34 and 36 are read into the microprocessor control 12 during a program logic cycle. The switches 34 and 36 may be, for example, DIP switches or equivalent devices. These parameters may also be provided in various ways such as by a digital device compatible with the microprocessor, such as a read only memory (ROM). A first control output 50 of the microprocessor is connected to the depression power contactor 32. The depression power contactor operates in response to the output 50 in order to activate or deactivate the depression pump 16 through line 52. Similarly, a second microprocessor control output 54 is provided to skim pump power contactor 30 which activates or deactivates the skim pump 14 through line 56. Depression pump 16 may be any suitable depression pump as is commercially available and well-known by those skilled in the art. Similarly, skim pump 14 may be any suitable, commercially available skim pump for pumping hydrocarbons. Both skim pump 14 and depression pump 16 are supported by well-known means in well 40. The skim pump 14 is advantageously placed at a position in the well which is proximate to the water interface. Depression pump 16 is located below skim pump 14 nearer to the bottom of the well where it is totally submerged in water and does not come into contact with hydrocarbon fluid product. Liquid sensor 22 and upper water interface sensor 23 may advantageously be housed together in upper probe 21. Liquid sensor 22 senses the presence of liquids. The liquid sensor may advantageously be a float switch. Other types of sensors could be used including sensors responsive to capacitance, optical refraction or thermal conductivity. Such devices are well-known in the art. The liquid sensor 22 provides a sensing signal transmitted on line 60 to a first input of the microprocessor control. Upper water interface sensor 23 is located adjacent to liquid sensor 22 and provides a water interface sensing signal on line 62 to a second input of the microprocessor control. An optional lower water interface sensor 24 of the same type as the upper water interface sensor may be included. If used, the lower water interface sensor 24 is preferably disposed between the skim pump and the depression pump intakes. Lower water interface sensor 24 also provides a sensing signal to a third input of the microprocessor control on line 64. The upper and lower water interface sensors may preferably be well-known conductivity sensors or equivalent devices. Other devices which may be used include float sensors which are buoyant in water, but not in hydrocarbon products. The depression pump 16 discharges water through conduit 66 to an appropriate discharge location 17. The skim pump 14 discharges hydrocarbon product into product tank 18 through conduit 68. The product tank 18 includes a high tank level sensor 20 which senses the tank level. A tank level sensing signal is presented by the high tank level sensor to a fourth input of the microprocessor control through line 70. Referring now to FIG. 2, an alternate embodiment of the apparatus which comprises the invention is shown. In the embodiment shown in FIG. 2, optional features have been added to the system shown in FIG. 1. These additional features include a communications bus 80, status display 82, external problem indicators 84, option select switches 86, and current sensors 90 and 92. The communications bus 80 may comprise any communication lines suitable for interfacing the microprocessor control with an external computer, such as a personal computer or main frame computer. Utilizing such a communications bus, an operator can easily monitor the well operation or modify a program in the microprocessor control to accommodate local special conditions. Optional select switches 86 may be provided for programming optional features such as engaging or ignoring the lower water interface sensor. Current sensor 90 provides a current sensing signal corresponding to the driving current in the skim pump referenced to a predetermined set point. If the current exceeds the predetermined set point, the microprocessor control processes the signal as indicating that the skim pump is pumping. Similarly, current sensor 92 measures the depression pump current and provides a signal on line 96 which corresponds to a measurement of whether or not the current in the depression pump exceeds a predetermined set point indicating that the depression pump is pumping. The signals from the optional current sensors may be used for monitoring operation of the well and are not employed in the preferred embodiment to effect the operation of the control system. Other optional features may be included to assure proper set up at a given well location. For example, jumpers may be supplied in the interface connectors (not shown) for the liquid sensor, upper water interface sensor, lower water interface sensor, and high tank level sensor to supply a continuity signal to the microprocessor controller when each of these devices is properly plugged into the control enclosure. Status display 82 may include a digital display to show the operating time of current operation which may, advantageously, optionally alternate with a display elapsed time from previous operations. Status lights may also be included in the display for indicating current conditions of sensors and the controller cycle. Some of the status displays may advantageously be driven directly by the input lines to the microprocessor control instead of being driven by the microprocessor. A watch dog timer 110 may also be included to provide a reset signal to the microprocessor control in the event of a processor malfunction such as the program counter jumping to execute a non-program, a memory overflow, endless loop condition, etc. This reset signal is supplied by lines 112. When the microprocessor is properly executing its program, it will periodically reset the watch dog timer. OPERATION OF THE INVENTION Having described the elements of the invention and their relationship to each other, it is believed that the features and advantages of the invention can be better appreciated through a detailed description of the operation and method of the invention as provided herein below. Referring now to FIG. 3, a high level flow chart illustrating generallY the method of the invention is shown. Those skilled in the art will appreciate that the precise order of events shown in FIG. 3 is not critical to the operation of the invention, but that many alternative configurations are possible to implement the principles of the invention. However, for the sake of illustrating the invention, the flow chart used in FIG. 3 will be used with the understanding that it is intended for illustration of the invention and not by way of limitation of the invention. At step 200, the system is turned on (or reset, as by the watchdog timer, depending upon the condition in which the process is being entered). The process then proceeds to step 210 wherein the microprocessor and variables, including initial values of outputs, flags and counters are set up and initialized. At step 212, the microprocessor internal real time clock is updated from a an internal microprocessor timer and the microprocessor oscillator. Next, at step 214 the microprocessor control reads and processes the various inputs as provided from the liquid sensor, upper water interface sensor, lower water interface sensor, high tank level sensor, and other external lines. After step 214, the microprocessor control proceeds to cycle through the depression pump logic at step 216 which is explained in more detail hereinbelow with reference to FIG. 4. Upon exiting the depression pump logic sequence at 216, the skim pump logic sequence is entered at step 218. The skim pump logic sequence is explained in more detail with reference to FIG. 5 herein. Upon completing the skim pump logic cycle at step 218, the processor optionally executes step 220 wherein outputs are provided to the display panel and problem indication devices 84. The microprocessor control continues to cycle through steps 212 through 220 until the system is turned off or reset. Referring now to FIG. 4, a more detailed flow chart of the control scheme of the depression pump as employed by one embodiment of the invention is shown. If the option select switches 86 are set to utilize the low water interface sensor, optional step 222 will be included in the computer algorithm being executed by the microprocessor. Otherwise the depression pump control scheme will begin at step 224. Assuming that the low water interface sensor option is selected, block 222 utilizes the input on line 64 in order to determine whether or not a low water interface is being sensed by the low water interface sensor 24. If the low water interface sensor is on, indicating that the water interface is at or above the low water sensor, the process flow continues to step 224. If the low water sensor is off, indicating that the water interface is below the low water sensor, the low water sensor output signal on line 64 will carry a corresponding electrical signal to the microprocessor control allowing the computer algorithm to proceed to step 232. At step 224, the microprocessor checks the timer for the depression pump cycle. If the timer has been set to zero, indicating the depression pump is currently off, the process proceeds to step 226. If the timer holds a value other than 0 the timer is incremented at step 228 and control then proceeds to step 230. Assuming the branch to step 230 is followed, the internal depression time is compared to the time delay set by depression pump switch 36 at step 230. If the timer is over the limit, control proceeds to step 232. At step 232, the timer is set equal to 0 which indicates that the pump has been turned off. Note that step 232 may also be entered from optional step 222 if the low water interface sensor is in the "off" condition. Step 232 is exited and control proceeds to step 234 wherein the depression pump is turned off by the microprocessor control operating through the depression pump contactor 32. Assuming that the "yes" branch from step 224 is executed, the processor then executes step 226 wherein the signal from the upper water interface sensor is read and processed by the microprocessor control to determine whether or not the water interface is at or above the high water sensor. If the signal from the upper water interface sensor 23 on line 60 indicates an "on" condition, this indicates that the water interface is at or above the upper water interface sensor and the process proceeds to step 236 wherein the timer is incremented and started. If the upper water interface sensor proVides a signal on line 60 indicating an "off" condition, that is, indicating that the water interface is below the upper water level sensor, the process branches to step 234, wherein the depression pump is kept off by the microprocessor control supplying an appropriate control signal to the depression pump power contactor 32. Step 240 is entered either via step 236 or the "no" branch of step 230. At step 240, the microprocessor control supplies an appropriate signal to the depression pump power contactor via lines 50 to turn the depression pump on. Following the above described control process, the depression pump will always run if the upper water sensor indicates that the water interface level is at or above the level of the upper water sensor. Further, the depression pump will run until the time delay as set by the depression pump switch 36 has elapsed. If the lower water interface sensor is used, it will override the time delay and assure that the depression pump does not run when the water interface is below the lower water interface sensor level. Referring now to FIG. 5, a flow chart showing the control scheme for the skim pump is shown. Decision step 242 is entered when step 216 has been completed. At step 242, the microprocessor control determines whether the skim pump is currently running. If the skim pump stops, the processor determines whether the depression pump has run since the skim pump stopped. This step is not essential to the operation of the skim pump but is useful in preventing short cycling of the skim pump. If the skim pump is running or the depression pump has run since the skim pump stopped running, the process proceeds to step 244 which determines whether or not the depression pump is off. In an alternate embodiment of the invention wherein the optional step 244 is eliminated from the logic flow shown in FIG. 5, the depression pump and the skim pump may operate concurrently. In such an alternate embodiment, step 242 would be replaced by an alternate step 242 to determine the status of the upper water interface sensor. If the upper water interface sensor was on for a few seconds, control would proceed to step 262. If the upper water interface sensor was off, control would proceed to step 246. Assuming step 244 is executed and the depression pump is not running, control then proceeds to decision block 246 wherein the microprocessor determines from the signal on line 60 whether or not the liquid sensor 22 is on. If the liquid sensor is on, it indicates the presence of hydrocarbon product. The liquid sensor may be, for example, a float switch. If the liquid sensor is on, process flow continues to step 248. At step 248, the signal on status line 70 is processed by the microprocessor control to determine whether or not the product tank 18 is full as indicated by the high tank level sensor 20. If the tank is not full, process flow continues to step 250 wherein the skim pump's current status is checked by the microprocessor control. If the skim pump is not running, the skim pump hold-off timer is checked at step 252. If the skim pump timer is set to 0, the timer is incremented at step 264 starting the timing process, and the skim pump is kept off at step 266 prior to exiting the control algorithm. If the skim pump timer is not equal to 0, the skim pump hold-off timer is incremented at step 254. At step 256, the skim pump hold-off timer is compared against the time limit as set by skim pump time delay switch 34. If the hold-off timer is over the limit, the timer is set to 0 and the skim pump is turned on. If the timer is under the limit, the skim pump is kept off at step 266 prior to exiting the routine. If any of the conditions at steps 242, 244, and 246 are determined to be negative, the skim pump hold timer is set to 0 at step 262 and the skim pump is turned off. If the product tank is full as determined at 248, the process also flows through steps 262 and 266 and then exits. Using the above control algorithm, the skim pump timer will not be activated during a predetermined time delay period which is initiated by the liquid sensor turning on. Further, the skim pump will not operate when the depression pump is running. Referring now to FIG. 6, a block diagram of yet a further alternate embodiment of the invention is shown. The difference between the embodiment shown in FIG. 6 and the embodiment shown in FIG. 1 is substantiallY in the introduction of modulating valve 400 and optional solenoid valve 402 which controls the water discharge from the depression pump. Only those elements significant to this alternate embodiment are shown and it will be understood that other elements as depicted in FIG. 1 may be used in combination with the system shown in FIG. 6 as necessary. In the scheme shown in FIG. 6, the depression pump is controlled only by the low water sensor and the water line 66 is controlled at the surface by a modulating control valve or motor controlled throttling valve 400. The valve 400 slowly opens when water is sensed at the upper water sensor 23 and slowly closes when water falls below the upper water sensor. The rate of opening and closing the valve may advantageously be set so as to control the water interface 58 at a substantially static level. The speed of opening and closing the modulating valve may be optimized using an algorithm executed by the microprocessor based on historical experience in the well being pumped. Optionally, a solenoid valve 402 may advantageously be added across the modulating valve. When using the solenoid valve, when the power is first turned on, the solenoid valve opens and the modulating valve does not move until the water interface falls below the upper water sensor. At that point, the solenoid valve may be inactivated and the modulating valve is used for the duration for the operation of the pump 16. Referring now to FIG. 7, a flow chart of another feature of the method of the invention is shown. As detailed in FIG. 7, the invention provides a computer algorithm executed by the microprocessor control for optimizing and dynamically changing the on-off cycle for the depression pump based upon prior experience data for a holding container, such as a well. At step 400, a series of initial recovery times for the water interface 58 are measured and stored in memory. The recovery time is defined as the time it takes for the water interface to return to the skim pump level as measured from the time the depression pump is turned off. The control then executes step 402 for calculating the optimum pump-on time initially based upon the measured initial recovery times found at step 400 and the optimum total cycle time for the depression pump as supplied by the manufacturer or as determined by the operator. Subsequent cycles through the algorithm will incorporate measurements of currently measured recovery times. The optimum pump-on time will usually be set to avoid short cycling of the skim pump. A tYpical total pump-on plus recovery time is about 15 minutes. The optimum pump-on time will vary from well to well. Once the optimum pump-on time has been calculated, the microprocessor adjusts the depression pump cycle time at step 404. At step 408 the current recovery time is monitored. The cycle then returns to step 402 and repeats while continuing to add to and use the historical data being accumulated for the well which includes the initial and current recovery times and the depression pump optimum total cycle time. FIG. 8 shows an example of a control panel provided by one embodiment of the invention. The control panel 300 is used to interface with operators running the system. The panel 300 comprises a printed circuit board 302 upon which are mounted switches 34 and 36, numerical display indicators 301 and front panel 303. Front panel 303 is divided into a plurality of segments including a SENSOR segment comprising indicators 310, 312 and 314, a first SKIM PUMP segment comprising indicators 316 and 318, a second SKIM PUMP segment comprising indicators 336, 338 and switch 339, a DEPRESSION PUMP segment comprising indicators 332 and 334 and switch 335, and a PROBLEM SEGMENT including indicators 322, 324, 326, and 328 and switch 330. The front panel 303 is positioned on the printed circuit board so as to align the DEPRESSION HOLD-ON nomenclature over depression switch 36 and the SKIM HOLD-OFF nomenclature over depression switch 34. Similarly, the nomenclature designating ERROR and ELAPSED CYCLE TIME is positioned under display indicators 301. Indicators 301 may comprise a plurality of seven segment numerical display devices or similar read-out devices. In one embodiment of the invention, two elements are used to display error indications and four elements are used to display elapsed time for the current and previous operating cycles. Indicators 304, 306 and 308 indicate the presence or absence of power to the system. In the SENSORS segment of the display, indicator 310 is designated as FLOAT, indicator 312 is designated HIGH WATER and indicator 314 is designated LOW WATER. When the indicators are lit, it is a signal to the operator that the named device or function is in the "on" condition or that the function named is "true". A typical device will be provided with both audio and visual alarms, therefore, in the PROBLEM segment of the control panel, the operator may turn off the audio alarm by positioning switch 330 in the SILENCE mode. As can be seen in FIG. 8, problem indication lights 322, 324, 326 and 328 are provided. Similarly, indicator lights are provided to indicate microprocessor control and running of the skim pump by lights 336 and 338 and depression pump by lights 332 and 334. Also, the operator may override automatic control of either the skim pump or the depression pump through utilizing switches 339 and 335, respectively. This invention has been described herein in considerable detail in order to comply with the Patent Statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment details and operating procedures, can be accomplished without departing from the scope of the invention itself.

The present invention provides a method and apparatus for removing floating, substantially immiscible liquids such as hydrocarbons from containers or wells containing both floating liquids and water. In one aspect of the invention, a microprocessor control receives and processes input signals from a liquid sensor, an upper water interface sensor and a skim pump. The skim pump is located in the well proximate to the water interface. The liquid sensor is located proximate to the skim pump. The upper water interface sensor is located adjacent to and below the liquid sensor. The microprocessor control is initialized by setting certain parameters such as the initial conditions for pump output values. The microprocessor controls and operates the skim pump in response to the input signals so as to operate the skim pump in a manner responsive to the input signals.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION The subject matter of the present invention relates to an improved core marking system for a borehole sidewall coring tool adapted for use in a wellbore. Sidewall coring tools are used for the purpose of obtaining a sample of a formation traversed by a wellbore. In the following discussion, the terms "sample", "sidewall core", "core sample" and "core" are used interchangeably. In each sidewall coring tool, a marker system is used to mark each sample of the formation in order to obtain an indication of the depth of the sample in the wellbore. For example, U.S. Pat. No. 4,714,119 to Hebert et al, which issued Dec. 22, 1987 (hereinafter referred to as "the Hebert patent") is directed to a sidewall coring tool that is adapted for cutting and obtaining sidewall cores of a formation traversed by the borehole, the direction of the cut being perpendicular to an axis of the borehole. The disclosure of the Hebert patent is incorporated by reference into this specification. However, although the marker system used in connection with the Hebert patent has performed adequately, a need has arisen for an improved, more reliable marker system for use in connection with borehole sidewall coring tools. The proper operation of a marker or indexing system is important because it is the principal method by which the retrieved sidewall samples are identified and correlated to the depths at which they were taken. Failure to properly identify the cores leads to the loss of all retrieved samples, since the interpretation, analysis and information concerning the retrieved samples is of value only when the correct depth of origin is known. If the depth of origin of one sample is unknown, the origins of all of the samples become subject to question. Therefore, the potential for failure of the entire operation exists when the marking system malfunctions. In a horizontal wellbore, such a service might not even be attempted if it was believed that no indexing system would be present or available. Typical operational problems, encountered by the operators of a sidewall coring tool, are high borehole fluid density and high borehole fluid viscosity. In gravity feed marking systems, such as those described in U.S. Pat. Nos. 4,449,593 and 4,714,119, proper functioning of the tool relies on having the marker fall into a core storage tube or vessel driven exclusively by the force of gravity. However, fluid densities can be high (sometimes in excess of twice the density of water). As the difference in the fluid density and the marker's density decreases, the buoyancy of the marker increases, and the tendency of the marker to fall decreases. High fluid viscosity is a more significant problem when the viscosity is high. The fluid is essentially a thick gel, and the markers as described in U.S. Pat. Nos. 4,449,593 and 4,714,119 are being held in suspension by the high viscosity fluid. This leads to erroneous placement or lack of placement of markers and subsequent improper indexing of core samples. This combination of high fluid density and high viscosity, which is commonly encountered, can prevent the marker from dropping at all. In high viscosity conditions, the markers tend to stick to the marker kicker and may be retracted when the marker kicker retracts. Examples of marker kicker devices are shown in U.S. Pat. No. 4,714,119 (element 65, "kicker foot") and U.S. Pat. No. 4,449,593 (element 72, "wafer ejector"). The problems presented by borehole fluid conditions exist in both horizontal and vertical tool positions. All of the above problems have been routinely cited by operating field locations as problems which they encounter during field operations. Another problem involves the debris which exists in and around the core storage area. Debris in the well bore can be present in the form of rock cuttings from the borehole drilling process left in suspension in the borehole fluid or rock fragments knocked loose from the borehole wall by the motion of the entire apparatus. In addition, the drilling of the sidewall sample itself produces debris. Debris obstructions in the area leading to the core storage area can prevent recovery of the sidewall sample. Further, debris can also impede the delivery of the marker to the core storage area if the debris accumulates in front of the marker itself. This prevents the marker from being moved to the proper position. In addition, debris inside the core storage tube occupies space which is designated for core storage, reducing the maximum number of samples which can be recovered. It has been found that the recovery from an oil well can be substantially increased in some cases by making the wellbore horizontal in the section of the well which will produce the petroleum. Recent improvements in the methods and practices for drilling of wells with horizontal boreholes have allowed horizontal drilling to become much more common place than was previously the case. It is common practice to refer to the well bore deviation with reference to the surface of the earth, so that well bores perpendicular to the surface of the earth are said to be vertical. In the course of evaluation of these wells, it is expected that most wireline formation evaluation tools must be able to operate in a horizontal position. Positioning the tool horizontally presents a new set of problems in addition to those posed by borehole fluid conditions. The system, used by the devices described in U.S. Pat. Nos. 4,449,593 and 4,714,119, has two problems: first, horizontal positioning removes the gravity force required to move the marker into the core storage tube; in these systems, the marker can either fall sideways away from the funnel as it is moved by the marker kicking device or it could fall into the funnel, and, depending on the angular orientation of the tool, fall out of the funnel into the borehole; and second, with the tool mechanism in the horizontal position, pieces of segmented, broken or fragmented cores are lost as the core is being directed to the core tube by the core pusher assembly. For the purposes of evaluation and analysis of the core, it is desirable to have as much of the core sample as possible. In addition, pieces of the core which fall out could jam the mechanism and prevent core removal. Segmented, broken and fragmented cores are observed reasonably frequently during sidewall coring operations. The condition of the core cannot be predicted, nor can it be assumed that recovered cores will be in one piece since the reasons for broken cores are also varying and unpredictable. Thus a properly functioning marking system is critical for wellsite operations in order to ensure that the sidewall coring tool can be considered for use in the maximum number of potential applications and in different situations. In addition, it is important in all situations that as much of the core be recovered as possible to allow for the optimal analysis of recovered samples. As a result, the need exists for an improved core marking system for use with a sidewall coring tool, which core marking system will reliably mark, index, and separate both whole and fragmented sidewall core samples regardless of the deviation of the wellbore in which the sidewall coring tool is disposed. SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to provide an improved core marking system for a sidewall coring tool, which core marking system will reliably mark, index, and separate both whole and fragmented sidewall core samples regardless of the deviation of the wellbore in which the sidewall coring tool is disposed. It is a further object of the present invention to provide an improved core marking system for a sidewall coring tool, which core marking system includes an adaptor block constructed of a magnetic material and utilizing a plurality of marker discs, each disc being made of a permanently magnetic material. It is a further object of the present invention to provide an improved sidewall coring tool which includes the improved core marking system, the improved core marking system including the adaptor block made of magnetic material and the marker discs made of permanently magnetic material, the improved sidewall coring tool including a flexible rubber boot connected to a core storage tube which is disposed in direct alignment with a core barrel out of which the core or formation sample is pushed, the direct alignment of the rubber boot and associated core storage tube with the core barrel creating, in effect, a continuous tube from the core barrel to the core storage tube for passage of the formation sample from the core barrel to the core storage tube. In accordance with these and other objects of the present invention, U.S. Pat. No. 4,714,119 to Hebert et al (the "Hebert patent"), already incorporated herein by reference, describes a sidewall coring tool which is capable of cutting core samples from the sidewall of a borehole; a core drilling mechanism of the sidewall coring tool is disposed in an elongate housing and is rotated from a vertical storage position to a horizontal operational position. In a significant improvement to the core marking system of the Hebert patent, marker discs made from a permanently magnetic material are used in conjunction with an adaptor block which is also constructed of a magnetic material and including a sleeve of non-magnetic material fitted internally. The magnetic marker discs are pulled by magnetic force into the magnetic adaptor block and fall into a core storage tube. The marker discs are permanent magnets with high magnetic field strength. This field strength can overcome the effects of high borehole fluid density, high fluid viscosity and lack of gravitational pull when the sidewall coring tool is disposed on its side in a deviated borehole. The force exerted on the marker discs resultant from the interaction of the magnetic fields of the marker discs and the adaptor block exceeds the gravitational force on the marker discs. As a result, the core marking system of the present invention performs acceptably and reliably regardless of the deviation of the wellbore in which the sidewall coring tool is disposed. The reliable kicking of the magnetic marker discs by the core marking system of the present invention ensures the retrieval of the markers even when the tool is in a horizontal position; in addition, the markers will not fall out of or away from the core storage tube. The magnetic marker, after it has pulled into the adapter, also serves to prevent the cores previously stored from moving out of the core storage tube. In addition, a flexible rubber boot lines up with the core barrel when the core is being pushed out of the core barrel. The clearance between the rubber and the end of the drilling bit is small, there being no large spaces through which pieces of the core sample can fall when the core is being transferred from the core barrel to the core storage tube. As a result of the boot, a continuous tube exists from the core barrel to the core storage tube. The boot is flexible so that a close fit with the core bit can be achieved without impeding the travel of the core bit in either direction of its motion. Even if a portion of the sidewall core is protruding from the core barrel, the boot will deform to allow passage of the sample as the bit swings back, the boot returning to its original shape. If the boot were made of a solid rigid material, well bore cuttings and debris could easily jam the bit against the boot and restrict bit motion. The boot has the additional benefit, in both vertical and horizontal orientations, that it will exclude debris from the opening leading to the core storage tube. The magnetic markers and flexible rubber boot are not interdependent, in that, should one feature be unavailable, the other will still function. Optimal tool functioning is obtained with both features in place. Further scope of applicability of the present invention will become apparent from the detailed description presented hereinafter. It should be understood, however, that the detailed description and the specific examples, while representing a preferred embodiment of the present invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become obvious to one skilled in the art from a reading of the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS A full understanding of the present invention will be obtained from the detailed description of the preferred embodiment presented hereinbelow, and the accompanying drawings, which are given by way of illustration only and are not intended to be limitative of the present invention, and wherein: FIG. 1 illustrates a side view of a conventional sidewall coring tool, the tool being shown after having completely drilled a core sample but prior to having broken off and retrieved the sample; FIG. 2 illustrates a cross sectional view of the sidewall coring tool of FIG. 1 when the coring motor of such coring tool is retracted, the illustrated features of FIG. 2 being placed in the same plane for ease of illustration since the illustrated features are not necessarily placed in the same plane with respect to each other in the actual coring tool apparatus; FIG. 3 illustrates a front view of the coring tool corresponding to FIG. 2; FIG. 4 illustrates a cross section of FIG. 2 taken along section lines A--A of FIG. 2, this cross section being a top view illustrating the marker kicker, the top of the core marker tube, and the column of magnetic markers in the marker tube at an instant in time before the marker kicker sweeps or kicks the marker from the marker tube position; FIG. 5 also illustrates a cross section of FIG. 2 taken along section lines A--A of FIG. 2, this cross section also being a top view similar to FIG. 4 at another instant in time after the marker kicker has swept or kicked the marker from the marker tube position to a location disposed at the top of the core storage tube; FIG. 6 illustrates the coring motor and bit including the retrieved core after the core has been broken off and the coring motor has swung back into the vertical position; FIG. 7 illustrates the mid-stroke position of the core pusher rod, the core pushing the magnetic marker disc down towards the core storage tube, the magnetic marker disc entering the non-magnetic sleeve; FIG. 8 illustrates the core pusher rod at the end of its stroke, the magnetic marker disc having fallen out of the non-magnetic sleeve and the core being pushed towards the core storage tube; FIG. 9 illustrates the coring tool mechanism in the horizontal position with the core pusher rod pushing a fragmented core into the actuator adapter towards the core storage tube; and FIG. 10 illustrates the coring tool mechanism in a vertical position with the flexible rubber boot preventing debris from entering the opening leading to the core storage tube. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a side view of a prior art sidewall coring tool is illustrated. In FIG. 1, a sidewall coring tool 10 is lowered into a wellbore 11 by a wireline 12. When an anchor shoe 14 is extended, the coring tool 10 contacts a wall 11a of the wellbore 11. A coring motor, which includes a drilling bit 16, is rotated thereby moving the drilling bit 16 from its original vertically disposed position to a horizontally disposed position as shown in FIG. 1. The drilling bit 16 drills into the formation 18 thereby collecting a core sample of the formation. The prior art sidewall coring tool 10 of FIG. 1 is fully described in U.S. Pat. No. 4,714,119 to Hebert et al, the disclosure of which has already been incorporated by reference into this specification. Referring to FIGS. 2 and 3, a cross sectional side view (FIG. 2) and a front view (FIG. 3) of the sidewall coring tool 10 of FIG. 1 is illustrated, the coring motor and attached drilling bit 16 of the coring tool 10 being disposed in the original vertically disposed position. In FIG. 2, a core storage tube 20 stores a plurality of core samples 22 which have previously been extracted from the formation 18 traversed by the wellbore 11, core samples which originated from different depths in the wellbore 11. In order to identify a particular one of the core samples 22 as having originated from a particular depth in the wellbore, a marker disc 24 is disposed between each core sample 22. As long as a marker disc 24 is disposed between each core sample 22, one can easily determine the depth in the wellbore 11 corresponding to each core sample 22. However, occasionally, a specific core sample corresponding to a specific depth in the wellbore will not be extracted from the formation and will not be stored in the core storage tube 20; if this happens, and a marker disc 24 is not disposed between each and every adjacent core sample 22 in the core storage tube 20, one cannot determine with any certainty the depth in the wellbore 11 associated with each and every other core sample 22 disposed in the core storage tube 20. Therefore, the core sample marker system, used in association with a sidewall coring tool disposed in a wellbore, must be highly reliable, especially when used in a wellbore having severe temperature, pressure and other environmental conditions, since the absence of even one marker disc 24 between a particular adjacent set of core samples 22 can cast serious doubt on the accuracy of the recorded depth location in the wellbore associated with each and every other core sample 22 stored in the core storage tube 20. In FIGS. 2 and 3, in accordance with one aspect of the present invention, the core storage tube 20 is threadedly connected to an actuator adaptor block 26. The actuator adaptor block 26 is made from a material of relatively high magnetic permeability, such as 17-4 PH SST, a precipitation hardening stainless steel (PH SST). The actuator adaptor block 26 is made of a material that would be considered "magnetic" but would not be considered as a "permanently magnetic" material. An internal sleeve 28 is disposed immediately above the core storage tube 20 within the actuator adaptor block 26, the internal sleeve 28 being made of a "non-magnetic" material. The purpose of the non-magnetic internal sleeve 28 is to produce an internal area within the magnetic actuator adaptor block 26 where the magnetic force is substantially reduced. In addition, a plurality of marker discs 24a are stored in a marker tube 30, each of the marker discs 24 and 24a being permanent magnets and having a high magnetic field strength. For example, the marker discs 24 and 24a can be comprised of Strontium Ferrite (SrO.6Fe 2 O 3 ), a commercially available magnet material. The marker discs 24 and 24a are each made of a magnetic material which is attracted to the magnetic material of the actuator adaptor block 26. The, non-magnetic internal sleeve 28 is disposed between a first, entry section or opening 26a of the actuator adaptor block 26 and the top 20a of the core storage tube 20. The entry section or opening 26a of the adaptor block 26, being magnetic, attracts the magnetic marker 24a which is stacked in marker tube 30 thereby causing the magnetic marker 24a to fall into the entry section 26a of the adaptor block; however, the internal sleeve, being non-magnetic, allows the magnetic marker disc 24a to fall further into the abyss which leads to the top 20a of the core storage tube 20. A core pusher rod 46 pushes the marker disc 24a into the core storage tube 20. A pusher spring 32 disposed within the marker tube 30 pushes the plurality of marker discs 24a upwardly within the marker tube. The marker tube 30 is also threadedly connected to the actuator adaptor block 26, the block 26 having a hole disposed therethrough which is co-extensive with the hole in the marker tube 30 adapted for stacking the plurality of marker discs 24a. A cover plate 34 is bolted to the top of the actuator adaptor 26, the cover plate 34 having a hole 34a disposed therethrough which is co-extensive with the hole within the internal sleeve 28. A flexible rubber boot 36, in accordance with another aspect of the present invention, is disposed immediately above the hole 34a in cover plate 34. The rubber boot 36 must be made of a flexible material so that, in the event any debris is disposed between the boot 36 and the drilling bit 16, or if the core sample hangs out of the end of the boot 36, the boot can flex thus avoiding potential jamming of the core sample marker system of the sidewall coring tool of FIGS. 2-3. In addition, the boot 36 serves as a raised guard which guards against entry of debris into the hole 34a in the cover plate 34 which leads to the core storage tube 20. Such debris can be cuttings left over from the drilling process, pieces of rock from the wellbore, etc. If such debris falls into the core storage tube 20, problems such as marker jamming could occur. A retaining plate 38 clamps the rubber boot 36 to the cover plate 34. The drilling bit 16 is connected to a coring motor barrel 40, which barrel 40 is adapted to retain the core sample which is retrieved from the wall 11a of the wellbore 11. The core motor barrel 40 is connected to the coring motor 42. The coring motor 42 and barrel 40 are physically disposed between two fixed plates 44. A side plate 48 is disposed next to in parallel with each fixed plate 44, as best shown in FIG. 3, the side plates 48 functioning as mounting apparatus for the fixed plates 44 and to join the upper and lower sections of the tool. A J-slot track 44a is disposed through each fixed plate 44. A pin connected to each side of the coring motor 42 is disposed through each J-slot track 44a in each fixed plate 44 enabling the coring motor 42, coring motor barrel 40 and drilling bit 16 to rotate from the vertically oriented position shown in FIG. 2 to a horizontally oriented position shown in FIG. 1 thereby further enabling the drilling bit 16 to drill into the formation 18, as shown in FIG. 1, and retrieve a core sample of the formation 18. The core sample, thus retrieved from the formation 18, is stored in the coring motor barrel 40. The coring motor 42, coring motor barrel 40 containing the core sample, and drilling bit 16 are then rotated from the horizontally oriented position of FIG. 1 to the vertically oriented position of FIG. 2. A core pusher rod 46 then pushes the core sample out of the coring motor barrel 40, through the rubber boot 36, into the internal sleeve 28, and into the core storage tube 20. FIG. 2 illustrates two such core samples 22 already stored in the core storage tube 20, a magnetic marker disc 24 being disposed between each core sample 22 in FIG. 2. Referring to FIGS. 4 and 5, a top cross-sectional view of the sidewall coring tool of FIG. 2, taken along section lines 4--4 of FIG. 2, is illustrated. In FIG. 4, the side plates 48 are shown disposed adjacent to the magnetic actuator adaptor 26. The magnetic marker discs 24a are shown stacked in the marker tube 30. The core storage tube 20 is disposed directly adjacent the marker tube 30. A rotating plate 50 is shown hinged to a oscillating actuator shaft 52, the rotating plate 50 having a serpentine shape, at 50a, for retaining one of the magnetic marker discs 24a. The rotating plate 50 moves from its position shown in FIG. 4 to its position shown in FIG. 5 in response to the oscillating motion of actuator shaft 52. The cover plate 34, rotating plate 50, core storage tube 20, and internal sleeve 28 are all made from a suitable material of low magnetic permeability, such that it is considered "non-magnetic"; an example of such a suitable material is 18-8 SST, an austenitic stainless steel. In FIG. 5, the rotating plate 50 moved from its position shown in FIG. 4 to the position shown in FIG. 5 in response to the oscillating movement of the actuator shaft 52; and, as a result, the magnetic marker discs 24a moved from their stacked position within marker tube 30 to a hole defined to be an opening to the core storage tube 20. In accordance with one aspect of the present invention, recall that the marker discs 24a are made of a permanently magnetic material, and that the actuator adaptor 26 is also made of a magnetic (although non-permanently magnetic) material; however, the cover plate 34, rotating plate 50, core storage tube 20, and internal sleeve 28 are all made from a suitable non-magnetic material of low magnetic permeability. As a result, in accordance with one major aspect of the present invention, each of the marker discs 24a will automatically be drawn into the first entry section or opening 26a of the magnetic actuator adaptor 26 regardless of the deviation of the wellbore in which sidewall coring tool of FIGS. 1-5 is disposed. In addition, since the internal sleeve 28 is made of a non-magnetic material, the core pusher rod 46 will easily be able to push the marker disc 24a from the internal sleeve 28 into the core storage tube 20. A functional description of the operation of the sidewall coring tool of FIGS. 1-5 (including the magnetic marker discs 24a, magnetic actuator adaptor 26, and non-magnetic internal sleeve 28 in accordance with the present invention) will be set forth in the following paragraphs with reference to FIGS. 6-8 of the drawings. The rotating plate 50 sweeps the marker disc 24a from its position within marker tube 30 to an opening 26a in the actuator adaptor 26 which leads to the core storage tube 20. It is absolutely essential that the marker disc 24a enter the opening 26a and enter the core storage tube 20 before the core sample is pushed out of the barrel 40, since, if the marker disc 24a fails to enter the opening 26a, the core sample in barrel 40 will be pushed out of barrel 40 and into the core storage tube 20 and there will be no marker disc separating the two adjacent core samples. As a result, there can be no certainty with regard to the accuracy of the depth in the wellbore associated with each core sample disposed in the core storage tube 20. However, in accordance with one major aspect of the present invention, since the marker discs 24a are made of a permanently magnetic material which is attracted to the actuator adaptor 26 (also made of a magnetic although non-permanently magnetic material), but the cover plate 34, the rotating plate 50 of FIGS. 4-5, the core storage tube 20, and the internal sleeve 28 are all made of a non-magnetic material of low magnetic permeability, each of the marker discs 24a stacked in marker tube 30 will automatically be attracted to and drawn into the entry section or opening 26a of the magnetic actuator adaptor 26 regardless of the deviation of the wellbore in which sidewall coring tool is disposed. The internal sleeve 28, being nonmagnetic, will reduce the magnetic attraction enough to allow the marker disc 24a, disposed in opening 26a, to fall into the abyss which leads to the top 20a of the core storage tube 20. Following the kicking of the magnetic marker 24a, the core drilling operation takes place. The coring motor 42 moves out along the J-slot track 44a in the fixed plate 44 towards the rock formation. The side plates 48 act as a mounting apparatus for the fixed plates 44 and also join the upper and lower sections of the tool. The coring motor barrel 40 which has attached to its end a coring drilling bit 16 spins as directed from the surface equipment. The drilling bit 16 and motor 42 are pushed into the formation and the bit 16 penetrates into the formation. When the motor 42 reaches the end of its travel in the J-slot 44a, the fixed plates 44 are pulled up so as to break off the core sample. In FIGS. 6-8, the motor 42, barrel 40, and bit 16 are retracted into a vertical position; the retrieved core 22a is held in the barrel 40. The core sample is being pushed out of the barrel 40 into the core storage tube 20. To move the sidewall core sample to the core storage tube 20, the core pusher rod 46, which is hydraulically actuated and can push with substantial force, moves down through the core barrel 40 and contacts the core 22a, pushing it through a hole 34a in the cover plate 34 and into the actuator adapter 26, as seen in FIG. 7. The core sample is pushed into contact with the marker 24a which now resides within the actuator adapter 26. The core pusher rod 46 continues to push the marker 24a and sidewall core sample down. The marker 24a is pushed into the internal area of the non-magnetic internal sleeve 28, as seen in FIG. 7. When this occurs, the magnetic force that is holding the magnetic marker disc 24a inside the actuator adaptor block 26 becomes very small; therefore, the marker disc 24a is free to fall into the core storage tube 20, which is the desired effect. If the marker does not fall (as would be the case when the tool is horizontal and no gravitational force is pulling the marker 24a into the storage tube 20), its resistance to being pushed by pusher rod 46 will be reduced and marker disc 24a will be pushed into the core storage area 20 along with the core. Previously cut and stored cores 22 are shown stacked in the core storage tube 20 with the magnetic markers discs 24 in their correct positions. At this point, the cycle has ended and the core pusher rod 46 remains in the fully extended position to prevent cores from coming back up and out of the core storage tube 20. The entire cycle as described above can be repeated to obtain another core if desired. Referring to FIGS. 9 and 10, the sidewall coring tool is shown in FIG. 9 in a horizontal wellbore with the core pusher rod 46 pushing a fragmented core into the actuator adaptor 26 toward the core storage tube 20, and the sidewall coring tool is shown in FIG. 10 in a vertical position with the flexible boot 36 preventing debris from entering the opening leading to the core storage tube 20. In accordance with another aspect of the present invention, the flexible boot 36 acts as an extension of the actuator adapter 26 and the core receiver tube. The boot 36 is fastened to the cover plate 34 by screws and a retaining plate 38. The retaining plate 38 holds down all sides of the boot 36. The flexible boot 36 serves two purposes. In FIG. 9, the first function of the boot 36 is to act as a guide from the core barrel 40 and bit 16 into the actuator adapter 26 and core receiver tube. The boot 36 occupies the space which exists between the top of the cover plate 34 and the end of the drilling bit 16. This means that when a core is broken or segmented, all of the pieces of the core will be guided into the core receiver tube for recovery, regardless of the tool position or angular orientation in the wellbore. The boot 36 is made from a flexible material so that if any debris gets between the boot 36 and the bit 16, or if the core sample is hanging out of the end of the boot, the boot 36 can flex out of the way, thus avoiding potential jamming. In FIG. 10, the second function of the boot 36 is to serve as a raised guard against debris, such as debris 54 in FIG. 10, which enters the hole 34a in the cover plate 34 which leads to the actuator adapter 26 and ultimately the core storage tube 20. Debris can originate from cuttings left over from the drilling process, cuttings from the sidewall core drilling process, and pieces of rock knocked from the borehole wall as the coring tool moves past. This debris accumulates on the cover plate 34 and falls into the core storage tube 20 causing problems such as marker jamming and occupying space in the core receiver tube that could otherwise be used for core storage. This is important because the tool operator has a limited amount of storage space and needs to be able to rely on having a known volume in which to store core samples. The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.

A system for reliably indexing and separating sidewall core samples obtained with a sidewall coring tool comprises markers made of a magnetic material and a mechanism body made of a combination of magnetic and non-magnetic materials to reliably insert and position markers in between successive core samples. The sidewall core is not altered in any way by the marking process. Further, a flexible rubber boot apparatus is disclosed to ensure the complete transfer of retrieved samples in cases where the sample is broken, shattered or segmented and to ensure that broken, shattered or segmented cores will be retrieved in cases where the borehole is horizontal and the tool must operate in a horizontal position or in any other rotational orientation.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to downhole oil well drilling and production tools and more particularly relates to an improved downhole running and pulling tool that can be conveyed into a well bore on continuous coil tubing or on threaded pipe, wherein the user has the option of detaching from a carried tool assembly if that assembly becomes stuck and/or plugged in the well bore (e.g. by sand or debris). The improved releasing mechanism is, more particularly, operable by pumping a deformable (for example polymeric) ball valving member through the coil tubing bore or through the work string bore until it seats on a piston. Pressure is applied from the surface via the work string or coil tubing until a pressure differential is reached across the piston which in turn shifts a piston, releasing a locking member that is held in place by a spring, shear pins, set screws or a combination of both allowing the device to part and leaving the stuck portion of the assembly in the hole to be fished out with other equipment. To reestablish circulation (i.e. the ability to pump fluid down the workstring and up the annulus of the well) pressure is increased across the seated ball forcing the ball through the seat into a ball cage. 2. General Background When remedial work is performed on oil and gas wells, and on occasion during the drilling of said wells, certain downhole tool assemblies are conveyed into the well bore on continuous coiled tubing or on a string of connected joints of threaded pipe. It often becomes desirable to have the option to detach from these tool assemblies. The tool assembly can become stuck and/or plugged in the hole by sand or debris for example. There are several known downhole tool assemblies which are operated by pumping a steel ball down the workstring. The ball valving member arrives at a releasing device and seats in a piston. Pressure is then applied from the surface through the workstring until a pressure differential is reached across the piston which in turn shears a set of pins or set screws. This movement releases dogs on a collet lock allowing the device to part, leaving the stuck assembly in the hole to be fished out. Some of the presently available releasing devices allow restricted circulation of fluid through the tool after release. None of the available or prior art devices are relatchable, nor can they be released more than one time. Some patents have issued that disclose devices for releasably connecting one part of the tools string to another. An example is the Smith U.S. Pat. No. 5,419,399 entitled "HYDRAULIC DISCONNECT". In the '399 patent, there is described an improved method and apparatus for releasably connecting one part of a tool string to another, comprising a tubular housing having an uphole and a downhole end, a piston slidably disposed within the tubular housing for longitudinal movement therein between a first position and a second downstream position, the piston having a sealable bore formed therethrough for passage of a pressurized fluid, first connectors for releasably maintaining the piston in the first position thereof prior to sealing of the bore in the piston, a tubular bottom sub having an uphole end for concentric connection to the downhole end of the tubular housing, and a downhole end adapted for connection to a tool string and second connectors for releasably connecting the tubular housing to the bottom sub to normally prevent axial separation therebetween, wherein the piston, upon sealing of the bore to block the passage of the pressurized fluid therethrough and in response to the pressure of the fluid then acting on the piston, is movable from its first to its second position to allow release of the second connectors, whereupon the tubular housing and the bottom sub become separable. U.S. Pat. No. 5,404,945 discloses a device for controlling fluid flow in oil well casings or drill pipes. The device defines a flow path for fluid through a casing section or drill pipe with the flow path including a throttling valve which restricts or prevents the flow of fluid therethrough. This can be used to prevent U-tubing in casings or can be used to locate leaks in drill pipes or can be used to monitor the position of successive fluids of differing viscosities in a casing string. An anti-rotation device for cementing plugs with deformable peripheral fins or lips is disclosed in U.S. Pat. No. 5,165,474. A method and apparatus for hydraulic releasing for a gravel screen is disclosed in U.S. Pat. No. 4,671,361. The '361 patents relates to a tool for use in gravel packing wells, and more particularly to a tool for retention and release of a gravel pack screen assembly when gravel packing wells. The method and apparatus is especially suitable for hydraulic releasing from a screen on a circulation type gravel pack job. The releasing tool comprises a tubular case by which the tool is secured to a gravel pack thereabove and a gravel screen secured thereto below. The case disposed within the collet sleeve assembly show room on top of the case and includes a plurality of collets extending downwardly into the case, the collets being radially outwardly biased into engagement with the case by the lowered end of a releasing mandrel disposed within the collet sleeve. A ball seat on the top of an axial bore extending through the releasing mandrel permits the seating of a ball and downward movement of the releasing mandrel inside the collet sleeve. Removal of the outward bias against the collets and permitting withdrawal of the collet sleeve and releasing mandrel from the case and attached screen therebelow. The Bissonnette U.S. Pat. No. 4,515,218 discloses casing hardware such as float collars and shoes used in oil well cementing operations. Some of the collars and shoes and constructed of a steel casing with a concrete core inside the casing. The casing structure of the collars and shoes places the core under a predominantly shearing force, so that it will fail at relatively low downhole differential pressures. The invention provides a design for the casing structure which places the concrete core under a predominantly compressive force and greatly increases the amount of pressure the core can withstand without failing. The Wetzel U.S. Pat. No. 3,997,006 discloses a well tool having a hydraulicly releasable coupler component, a gravel packing apparatus and method for use therewith and a subterranean well having production tubing inserted therein, wherein the coupler comprises hydraulic means for releasing the tubing from the gravel pack apparatus, without rotating said tubing when the coupler is activated and the tubing removed, the lower portion of the coupler remaining in the well with the gravel pack and providing a receptacle for a packing element partially inserted therethrough. An oversize subsurface tubing pump installation and method of retrieving the pump is disclosed in U.S. Pat. No. 3,809,162. Both the pump barrel and plunger are too large to pass through the tubing. When the pump is to be retrieved, the sucker rods are raised and lift the seating assembly to expose a drain hole in the seating nipple. Fluid drains from the tubing through the exposed drain hole. Continued raising of the sucker rods breaks the connection between the sucker rods and the pump plunger. The sucker rods and then the tubing and pump are pulled from the well. Draining the tube prevents spillage at the top of the well. A method and apparatus for cementing casing sections and well bores is disclosed in U.S. Pat. No. 3,570,603. Casing sections are cemented in a well bore between producing zones and an upward sequence starting from the bottom. Each casing section is lowered on a running string and running tool to its sitting position, the casing section then being rotated to expand cutter supporting members carried by the casing outwardly to cut a formation shoulder for supporting the cutter members and casing. The running tool is released from the casing and lowered therewith to the casing float shoe, cement being pumped through the running string, tool and shoe to cement the casing in place, running string and tool being removed from the hole. SUMMARY OF THE INVENTION The present invention provides a downhole oil well tool apparatus that includes an inside fishing neck on the main body of the device. One of the tools designed to latch with the fishing neck is for example a pulling tool, such pulling tool devices as have been commercially available for years. The present invention provides a bias that allows piston movement in a releasing device in place of shear pins or shear screws. A composite ball allows more than one pressure setting to actuate the locking and unlocking piston. The apparatus of the present invention provides the capability to unlatch and relatch numerous times, using the composite ball by moving the ball through a seat, deforming the ball with pressure. The present invention allows full circulation of fluid after actuation by forcing the deformable ball valving member through the seat. The apparatus of the present invention includes a cage portion that catches each of the deformable ball valving member in a cage to prevent those deformable ball valving members from freely moving into the well bore and further restricting flow. The apparatus of the present invention includes multiple serrated dogs to transfer torque between the two main body parts of the apparatus to permit those two major components to remate with ease. BRIEF DESCRIPTION OF THE DRAWINGS For a further understanding of the nature and objects of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawings, in which like parts are given like reference numerals, and wherein: FIG. 1 is a sectional elevational, partially cut-away view of the preferred embodiment of the apparatus of the present invention. FIG. 2 is a sectional view illustrating the preferred embodiment of the apparatus of the present invention, showing the tool in locked position; FIG. 3 is a sectional view of the preferred embodiment of the apparatus of the present invention illustrating the tool in a pressured up position; FIG. 4 is a sectional view of the preferred embodiment of the apparatus of the present invention showing the mandrel removed, the ball valving member having been pumped through to the ball cage to allow circulation; FIG. 5 is a sectional view of the preferred embodiment of the apparatus of the present invention illustrating the placement of a second ball valving member used to unlock the tool for mandrel reinstallation; FIG. 6 is a sectional view of the preferred embodiment of the apparatus of the present invention illustrating the mandrel having been reinstalled; FIG. 7 is a sectional view of the preferred embodiment of the apparatus of the present invention showing the second ball having been pumped through to the ball case to relatch and resume operations; FIGS. 8A-8B are side views of the deformable ball valving member showing its configuration before (FIG. 8A) and after (FIG. 8B) it is pumped through to the ball cage; FIG. 9 is an elevational sectional view of an alternate embodiment of the apparatus of the present invention; FIG. 10 is an elevational sectional view of a second alternate embodiment of the apparatus of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1-3 show generally the preferred embodiment of the apparatus of the present invention designated by the numeral 10. Pulling and releasing tool 10 has an upper end portion 11 and a lower end portion 12 when the tool is assembled and oriented in operating position for running in a well. A flow bore 14 allows circulation through the tool 10 between end portions 11, 12. The apparatus 10 includes a main body portion 13 having an inner open ended bore 18. At the lower end portion of the main body 13 that is provided a threaded sub member 15. The sub member 15 forms a connection to main body 13 at threaded connection 16. The sub 15 provides lower external threads 17 for attaching main body 13 to other tools, tool sections, pipe or the like. The main body 13 (FIG. 4) has an upper end portion 19, and a lower end 20. Open ended bore 18 receives an inner mandrel 28. The main body 13 includes a generally tubular cylindrically shaped main body wall 21 with an inside surface 22. A pair of spaced apart beveled annular shoulders 24, 25 define therebetween an annular recess 23. The side wall of the main body 13 has a thin side wall 26 at the annular recess 23. On the sides of the annular recess 23, there are provided thick side wall portions 27 as shown in FIG. 4. The main body 13 receives an inner mandrel 28, a fluid pressure operated piston 29 and locking dogs 30 that are used to engage the inner mandrel 28 and main body 13. In FIG. 4, mandrel 28 has an upper end 32 and a lower end 31. Inner mandrel 28 has a bore 33 that extends completely through inner mandrel 28. Piston 29 occupies a portion of bore 33 as shown in FIG. 4. The inner mandrel 28 provides an internally threaded connection portion 34 for attachment to a coiled tubing string, work string or the like during use. Threaded connection portion 34 enables a user to raise and lower the tool 10 in an oil/gas well using a coil tubing unit for example. The piston 29 is hollow, providing a piston bore 35. The piston 29 has an upper end 36 defining a ball valve seat 57. O-ring 37 forms a seal with inner mandrel 28. Annular ring 40 limits travel of piston 29 in an upward direction. In FIG. 1, annular ring 40 is in an uppermost position. Beveled annular surfaces 38, 39 are provided on each side of annular ring 40. Stop 46 is provided on inner mandrel 28 in the form of a beveled annular shoulder. Annular shoulders 39 and 42 define therebetween a reduced diameter annular recess 44. Piston 29 is of a reduced diameter at 43. A thickened section 45 is provided between annular recess 44 and ball cage 50. Stop 46 limits the travel of piston 29 within the bore of main body 13. Annular shoulder 47 and beveled annular surfaces 48, 49 define ball cage 50. Ball cage 50 is in an expanded area for receiving ball valving members 52, 53 that are pumped through when inner mandrel 28 is to be released from main body 13. When a ball valving member 52, 53 is pumped from seat 57 to cage 50, it deforms because it must pass through a reduced diameter section of piston bore 35. A cross bar 51 holds the ball valving members 52, 53 within the ball cage 50 after each ball valving member 52, 53 has been pumped therethrough. Otherwise, fluid can flow through cage 50 to the lower end of bore 33. The ball cage 50 is preferably sized to hold as many as six ball valving members (such as 52, 53) after they have been pumped through. Spring 54 biases the piston 29 in an uppermost position as shown in FIG. 1. The spring 54 has an upper end 55 and a lower end 56. Upper end 55 engages the lower end of piston 29. Lower end 56 of spring 54 engages spring stop 58 as shown in FIG. 4. During use, the apparatus 10 is lowered into the well bore on a work string such as a coil tubing string. The apparatus 10 assumes the position of FIG. 1 when being lowered to the well bore. In this initial position, spring 54 biases the piston 29 in the upper position shown in FIG. 1. The spring 54 bottoms on stop 58 and engages the lower end of piston 29. Stop 58 threadably attaches at connection 59 to inner mandrel 28. The piston 29 upper end provides annular ball valving seat 57 that is receptive of a ball valving member 52 or 53. If the tool 10 becomes stuck, it is desirable to release the inner mandrel 28 portion of the apparatus 10 from the main body 13. In such a case, the user pumps a ball valving member 52 into the well bore via a coil tubing unit which has an internal flow bore. When the ball valving member 52 reaches the ball seat 57 and registers upon seat 57, the ball valving member 52 forms a closure with seat 57. This closure prevents the flow of fluids from the coil tubing unit bore into the tool body bore 14. The user then pressures up the coil tubing unit which increases pressure on ball valving member 52, 53. The use of a coil tubing unit to "pressure up" above a ball valving member is known in the art. With the present invention, a deformable ball valving member is selected, such as a ball valving member of a plastic material. There are two basic operating pressures, a first pressure shifts tool (piston), a second pressure forces the ball 52 or 53 thru seat 57. This allows pressure to be increased to a predetermined value (first pressure) overcoming the force of bias spring 54, moving piston 29 down and releasing dogs 30. The ball valving member 52 deforms and passes through the ball seat 57 downwardly via the bore 53 and into the ball cage 50. This takes place at the second predetermined pressure value number two. The ball valving member 52 is of a deformable material such as a plastic polymeric material, Telfon® or nylon being preferred. Once the ball valving member 52 or 53 is pumped from the seat 57 into the ball cage 50 via piston bore 35, the user can circulate fluids into the well. Circulation is possible because the ball valving member 52 no longer forms a closure at the ball seat 57. The ball cage 50 is large enough to hold more than one ball valving members 52, 53. Cross bar 51 prevents further downward movement of ball 52 or 53 once the ball 52, 53 reaches cage 50. Fluid circulation is allowed because the cage 50 is larger in cross section than a plurality of the ball valving members 52, 53. One of the features of the apparatus 10 of the present invention is the ability to reinstall the mandrel 28 after it has been released. After mandrel 28 is removed from main body 13, and ball 52 has been forced through piston 29 spring 54 forces piston 29 up to the position of FIG. 4. In order to reattach, piston 29 must be moved down to the position shown in FIG. 5 so that the dogs 30 and recess 44 are adjacent. In this position, the mandrel 28 and dogs 30 have an overall diameter that will fit inside bore 18 of main body 13. A reattachment is accomplished by dropping a second ball valving member 53 via the coil tubing string to the seat 57. Once the second ball valving member 53 is in a sealing position on seat 57 (see FIGS. 5-6). The device 10 is pressured to the first pressure value allowing dogs 30 to move inward as in FIG. 5. Mandrel 28 can now be lowered into main body 13 as overall diameter is reduced. The mandrel 28 and its piston 29 can be reconnected to bore 18 of main body 13 as shown in FIG. 6. A smaller overall diameter of dogs 30 is achieved by pressuring up the bore 33 above ball valving member 53 to the first preselected pressure value. This forces piston 29 downwardly to the position shown in FIGS. 5 and 6. The mandrel 28 can now fit bore 18 of main body 13. To interlock mandrel 28 and body 13, ball valving member 53 is pumped through to cage 50 at the second preselected pressure value. Spring 54 then returns piston 29 and dogs 30 to locked or connected position. This attachment and disattachment can be repeated over and over if desired until cage 50 is filled with ball valving members. In FIG. 8A, a spherical ball valving member 52 is shown before being pumped through to bull cage 50. In FIG. 8B, a deformed ball valving member 52 is shown having a cylindrical outer surface portion 52A and a pair of opposed hemispherical outer surface portions 52B, 52C. FIG. 9 shows an alternate embodiment of the apparatus of the present invention by the numeral 60. The tool 60 is constructed as the tool 10 of the preferred embodiment, but for the elimination spring 54. Tool 60 has a shear pin 61 in the embodiment of FIG. 9. The tool 60 is a construction that is not designed to be reset. When a ball valving member 52 or 53 is dropped from the wellhead and travels via coil tubing unit bore to seat 57, the piston 29 can be shifted downwardly by pressuring up within the coil tubing bore. This pressuring up shears pin 61 allowing piston 29 to travel downwardly until recess 44 aligns with dogs 30 as with the preferred embodiment tool 10. However, no spring 54 is provided, so that resetting is not possible. Full circulation is however provided. FIG. 10 shows a second alternate embodiment of the apparatus of the present invention designated by generally by the numeral 60. Pulling and releasing tool 60 provides an embodiment that solves an inherent problem of ball operated tools that are shear pin operated. One of the inherent problems ball operated tools that use shear pins is that they are prone to shear and release when debris is accidently picked up by circulating pumps and conveyed downhole into the well bore. Before this debris can be blown through to a safety zone using extra pressure, sufficient differential pressure is often created to shear the pin or pins causing premature release. The debris will generally blow through the tool after this premature release occurs with the shearing of the pins. With the embodiment of FIG. 10, a shifting of inner piston 29 is delayed briefly. This delaying of the shifting action of piston 29 allows any debris that lodges in seat 29 sufficient time to clear the seat before shifting can occur. The alternate embodiment of FIG. 10 provides an improvement to prior art type ball operated tools of the type that have a shear pin holding arrangement. A delayed shifting of the inner piston of a ball operated tool is not possible with a shear pin held device, but is feasible with a spring loaded device such as is shown in FIG. 10 and described hereinafter. In FIG. 10, tool 60 includes the same main body 13 as with the embodiment of FIGS. 1-8. The embodiment of FIG. 10 has a mandrel 28 that is sized and shaped similarly to the mandrel 28 of FIGS. 1-8. Likewise, the embodiment of FIG. 10 provides a piston 29 that is slidably movable within the bore of mandrel 28 as with the embodiment of FIGS. 1-8. In FIG. 10, piston 29 also includes the same annular recess 44 and the same locking dogs 30 as the embodiment of FIGS. 1-8. The tool 60 is operated by dropping a ball from the surface and allowing that ball to flow via a coil tubing unit to seat 57 as occurs in the embodiment of FIGS. 1-8. However, the embodiment of FIG. 10 includes a timer or clock arrangement that delays operation of the releasing mechanism. This clock capability is in the form of a chamber 61 that holds coil spring 62 and cylindrical tube 63. The tube 63 has an upper end 64 that fits an annular shoulder 65 at the bottom of piston 29 and is sealed by welding. The lower end 66 of tube 63 fits the bore 33 of spring stop 58. Seals are provided at 67, 68. The lower end 66 of cylindrical tubes 63 provides a small orifice 69. The area between mandrel 28 and cylindrical tube 63 forms a chamber 61 that carries spring 28. Chamber 70 is sealed at the top with seal 67 and at the bottom with seal 68. Therefore, in order to move the piston 29 downwardly so that the locking dogs 30 can register in the annular recess 44, the tube 63 must also move down with the piston 29. Downward movement of the piston 29 and tube 63 is slowed because fluid contained within chamber 61 must flow through orifice 69 into the center bore 70 of tube 63 as shown by arrow 71. This arrangement produces a delay device or "clock" slowing the cycle time of the release sufficiently to allow most of any debris to clear the device without activation. The spring 28 will return the apparatus to is initial position shown in FIG. 10 if in fact debris has been the cause of a restriction at seat 57. The debris should clear the seat before release takes place so that the spring then returns piston 29 to the position shown in FIG. 10. The following table lists the parts numbers and parts descriptions as used herein and in the drawings attached hereto. ______________________________________PARTS LISTPart Number Description______________________________________10 pulling and releasing tool11 upper end portion12 lower end portion13 main body14 inner open ended bore15 threaded sub16 threaded connection17 lower external threads18 internal bore19 upper end20 lower end21 main body wall22 inside surface23 annular recess24 annular shoulder25 annular shoulder26 thin side wall27 thick side wall28 inner mandrel29 piston30 locking dogs31 lower end32 upper end33 bore34 internally threaded portion35 piston bore36 upper end37 o-ring38 beveled annular surface39 beveled annular surface40 annular ring41 annular shoulder42 beveled annular surface43 reduced diameter portion44 annular recess45 thickened section46 stop47 annular shoulder48 beveled annular surface49 beveled annular surface50 ball cage51 cross bar52 ball valving member 52A cylindrical surface.sup. 52B hemispherical surface.sup. 53C hemispherical surface53 ball valving member54 spring55 upper end56 lower end57 ball seat58 spring stop59 threaded connection60 pulling and releasing tool61 chamber62 spring63 tube64 upper end65 annular shoulder66 lower end67 seal68 seal69 tube orifice70 tube bore71 arrow______________________________________ Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.

A downhole oil well pulling and running tool provides a releasable tool body that can be used to release a workstring such as a coiled tubing string from a tool assembly and to reattach if desired. To reestablish circulations (the ability to pump fluid down the workstring and up the annulus of the well) after detachment by increasing the pressure across a seated ball to a predetermined pressure that forces the ball through the seat into a ball cage. The cage is sized and shaped to carry a plurality of the ball valving members so that the unlatching and relatching procedure may be repeated as many times as desired until the ball cage is filled. Also providing a delay or timing system that will allow debris to pass thru the tool without a release.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF INVENTION [0001] The present invention relates to floor covings, particularly floor covings suitable for use in special purpose buildings that generally require a clean environment, such as those used for handling, storage or processing of food and pharmaceuticals, or those used in various fields of scientific research. BACKGROUND ART [0002] In many industries there is a requirement that a very clean working environment be maintained. For example, various industries that involve food preparation or storage may require cleanliness in order to meet health and safety obligations and standards. These industries, which may include for example food suppliers such as bakeries, cafes and butchers, food packagers and food manufacturers will generally require clean flooring and cleaning of that flooring on a daily basis. [0003] In the pharmaceutical industry, manufacturing conditions sometimes require relatively high levels of cleanliness, up to and including cleanroom specifications. Manufacturing of electronics may also see such requirements. High levels of cleanliness are often also required in many fields of scientific research where contaminants must be avoided as much as possible. [0004] Floor covings have been proposed that provide for a concave face that extends between wall and floor to avoid the generally 90° corner that would otherwise be evident. In the above described industries this may be advantageous as the presence of such coving will remove the risk of food or contaminants collecting in the corner join between the wall and floor. [0005] In other instances, during construction floors and walls are prepared with a concave surface between them, avoiding the need for separate floor covings to be applied post-construction. [0006] It is considered that many floor covings that are currently available still have issues in that they may be difficult to apply to existing structures and/or may result in joins that promote the undesirable collection of food or other contaminants. [0007] The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. This background is provided to illustrate exemplary technology areas where some embodiments of the invention described herein may be practiced. SUMMARY OF INVENTION [0008] One aspect of the present invention provides a floor coving comprising: [0009] a vertical section that in use abuts a vertical structure; [0010] a horizontal section that in use abuts a floor extending from said vertical structure; and [0011] a concave surface extending between the vertical section and the horizontal section, said concave surface being adapted to support a pliable layer of flooring material in use, [0012] wherein an upper surface of said vertical section is declined towards said concave surface. [0013] The upper surface of said vertical section may be declined at any suitable angle. This advantageously alleviates potential issues relating to collection and retention of contaminants, for example if the upper surface of the vertical section was a flat horizontal surface. In a preferred embodiment, the upper surface is declined at about 45°, but may also be declined at from 20-70°, or 30-60°, or 40-50°. In other embodiments, the upper surface of the vertical section extends from a distal edge of the vertical section and is contiguous with the concave surface. That is, the upper surface of the vertical section may taper to a fine edge. [0014] In preferred embodiments a continuous bevel extends between an abutment face of said vertical section that in use abuts said vertical structure and an abutment face of said horizontal section that in use abuts said floor. The continuous bevel may advantageously ensure a good fit of the floor coving when applied to junctures of vertical structures, such as walls and fittings, and the floor. This is particularly so when the juncture is not a right angle corner. [0015] In even more preferred embodiments, the floor coving comprises a continuous step section cut into said abutment face of said vertical section and extending vertically from said continuous bevel. This advantageously facilitates application of the floor coving to junctures that already have a section of skirting or boxing applied, for example in the event of sandwich panel installation. That is, the continuous step section of the floor coving accommodates the existing skirting or boxing ensuring a good fit of the floor coving on the existing juncture and skirting or boxing. [0016] To that end, in alternative embodiments, the invention provides a floor coving comprising: [0017] a vertical section that in use abuts a vertical structure; [0018] a horizontal section that in use abuts a floor extending from said vertical structure; and [0019] a concave surface extending between the vertical section and the horizontal section, said concave surface being adapted to support a pliable layer of flooring material in use, [0020] wherein a continuous bevel extends between an abutment face of said vertical section that in use abuts said vertical structure and an abutment face of said horizontal section that in use abuts said floor, [0021] and wherein a continuous step section is cut into said abutment face of said vertical section and extends vertically from said continuous bevel. [0022] In certain embodiments, the vertical section comprises a substantially planar upper portion comprising a planar surface extending from said upper surface of said vertical section, said planar surface of said planar upper portion being contiguous with said concave surface. In other embodiments, the vertical section and horizontal section are substantially equal in length and the concave surface is substantially uniform extending along the length of both of the vertical and horizontal sections. [0023] In certain embodiments, the concave surface tapers to an edge of said horizontal section. That is, there is little or no step at the juncture of the horizontal section and the floor. This may advantageously ensure that flooring material applied over the horizontal section in use does not display a raised ridge where the flooring material overlays the juncture of the horizontal section and the underlying floor. In certain embodiments, for example, the concave surface tapers to about 1 mm or less along said edge of the horizontal section. [0024] The height of the vertical section and depth of the horizontal section are not particularly limited. Generally, the height of the vertical section will be at least equal to the depth of the horizontal section. In certain embodiments, the ratio of height of said vertical section to depth of said horizontal section is from 1:1 to 2:1. For example, the height of the vertical section may be from 50 to 150 mm and the depth of the horizontal section may be from 25 to 75 mm, although it will be appreciated that the invention is not so limited. [0025] In certain embodiments, one or both of said vertical section and said horizontal section comprises one or more grooves or shallow incisions. It is envisaged that in certain situations this may assist in the application of the floor coving. It is also thought that such grooves or shallow incisions may be included in place of any continuous bevel, as described above. Although, floor coving including both features is considered within the ambit of the present invention. [0026] The floor coving may be applied in any suitable manner. For example, adhesive may be applied to the floor coving prior to application of the floor coving to the vertical structure and floor. Fasteners, such as screws or rivets are not preferred as these would provide areas for collection of contaminants and, as such, if these fasteners were used one would also need to fill any fastening points to remove this potential issue. In more preferred embodiments, one or both of said vertical section and said horizontal section comprises a longitudinally extending strip of releasable paper that when removed exposes a band of contact adhesive adapted to adhere said vertical section and said horizontal section to said vertical structure and said floor respectively. [0027] The floor coving may be manufactured by any suitable method. For example, this may be injection moulded or produced through a forming process. Preferably, the floor coving is constituted by a unitary extrusion of resilient synthetic material. In that regard, the floor coving may be extruded and cut into lengths appropriate to the building industry of a particular jurisdiction. For example, the floor coving may be cut to lengths of from 3 to 6 m, or any other length deems appropriate for a particular application. [0028] Although the floor coving may be formed from any suitable material, including but not limited to metals or metal alloys, as noted above the floor coving is preferably extruded from a resilient synthetic material. Preferably, the resilient synthetic material is flexible and has a Shore A Hardness of from 80-85. Preferably, the resilient synthetic material is resistant to thermal degradation over a relatively wide operating range. For example, the floor coving may be required in refrigerated conditions and elevated processing temperatures. As such, the resilient synthetic material preferably has resistance to thermal degradation over a range of from −40 to 120° C. The resilient synthetic material forming the floor coving, according to this embodiment, is preferably selected from synthetic rubbers and vinyl polymers. Other suitable polymeric materials may also be employed. In particular embodiments, the resilient synthetic material is neoprene or polyvinyl chloride. [0029] In certain applications, it is envisaged that it may be desirable to include additives in the resilient synthetic material forming the floor coving. For example, the resilient synthetic material may contain an additive selected from a fungicide, a bactericide, and antimicrobial and a pigment or a combination thereof. Specific examples of antimicrobials and fungicides include members of the VINYZENE™ range supplied by The Dow Chemical Company. Such additives may be included in amounts of, for example, up to about 5 wt. %. Pigments may be included to impart a desired colour to the floor coving, removing the need for subsequent painting. [0030] According to another aspect of the invention there is provided a method of flooring a room comprising: [0031] applying floor coving according to any one of the preceding claims to junctures between vertical structures and a floor in said room, such that vertical sections of said floor coving abut said vertical structures and horizontal sections of said floor coving abut said floor; and [0032] laying a flooring material on said floor, [0033] wherein edges of said flooring material extend over said horizontal sections of said floor coving and at least part way up said vertical sections of said floor coving, conforming to contours of the concave surface of said floor coving. BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS [0034] To further clarify various aspects of some embodiments of the present invention, a more detailed description of the invention will be rendered with references to the accompanying drawings. It should be appreciated that these drawings depict certain embodiments of the invention and should therefore not to be considered limiting on its scope. The invention will now be described and explained with additional specificity and detail through the accompanying drawings in which: [0035] FIG. 1 illustrates a floor coving of an embodiment of the invention. [0036] FIG. 2 illustrates an expanded plan view of a floor coving of an embodiment of the invention, including contact adhesive strips. [0037] FIG. 3 illustrates a floor coving of another embodiment of the invention. [0038] FIG. 4 illustrates a floor coving of a further embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0039] Hereinafter, this specification will describe the present invention according to the preferred embodiments. It is to be understood that limiting the description to the preferred embodiments of the invention is merely to facilitate discussion of the present invention and it is envisioned without departing from the scope of the appended claims. [0040] Referring to FIG. 1 , a floor coving 10 is illustrated. The floor coving 10 includes a vertical section 11 and a horizontal section 12 disposed at about 90° to one another. The vertical section 11 includes an upper surface 13 that declines at 45° towards a concave surface 14 that extends between the vertical section 11 and the horizontal section 12 . [0041] The dimensions of the vertical section 11 , horizontal section 12 and concave surface 14 may be somewhat dependent on the application intended for the floor coving 10 . For example, as noted above, the height of the vertical section 11 may be from 50 to 150 mm and the depth of the horizontal section 12 may be from 25 to 75 mm. An exemplary radius for the concave surface 14 is about 50 mm, although the radius of the concave surface 14 may be any dimension, for example from 40-60 mm, or 45-55 mm. [0042] The concave surface 14 tapers towards an edge 16 of the horizontal section 12 . Generally, the edge 16 will taper to 1 mm or less, ensuring flooring material that is overlaid does not include a ridge caused by the underlying edge 16 . [0043] An expanded view of a floor coving 20 is illustrated in FIG. 2 . Again, the floor coving 20 includes a vertical section 21 , a horizontal section 22 and an upper surface 23 to the vertical section 21 . A bevel 25 is located between the vertical section 21 and the horizontal section 22 . An abutment face 26 of the vertical section 21 and an abutment face 27 of the horizontal section 22 include contact adhesive 28 underlying a strip of releasable paper 29 . On removal of the strips of releasable paper 29 , the contact adhesive 28 on the abutment faces 26 , 27 of the vertical section 21 and horizontal section 22 may be applied to a vertical structure and floor respectively. [0044] FIG. 3 illustrates an example of floor coving 30 of an embodiment of the invention in situ. As illustrated, an abutment face 36 of a vertical section 31 of the floor coving 30 is adhered to a vertical structure 38 , while an abutment face 37 of a horizontal section 32 is adhered to a floor 39 . Pliable flooring material 33 overlays the horizontal section 32 , extends over much of the concave surface 34 an up the vertical section 31 . [0045] In this embodiment of the floor coving 30 , the previously described bevel is replaced by grooves 35 . The grooves 35 provide some give in the floor coving 30 in the event the fit of the floor coving 30 relative to the vertical structure 38 and the floor 39 requires some compression of the floor coving 30 . For example, the grooves 35 may be useful if the vertical structure 38 does not meet the floor 39 at a right angle. [0046] Referring to FIG. 4 , an alternative embodiment of a floor coving 40 is illustrated. In this embodiment, again, a vertical section 41 and horizontal section 42 are provided, as is a concave surface 44 and a bevel 45 . In this embodiment, a step 48 is cut away from an abutment face 46 of the vertical section 41 . As discussed above, this provides advantages in situations where the floor coving 40 is to be applied to a vertical structure that includes skirting or boxing applied to it. That is, the step 48 may advantageously accommodate the skirting or boxing ensuring a suitable fit of the abutment face 46 with the vertical structure to which it is applied. As illustrated, the vertical section 41 of the floor coving 40 includes a declined surface 43 , although it is envisaged that the inclusion of the step 48 will provide advantages to the floor coving 40 irrespective of the inclusion of the declined surface 43 . That is, embodiments of the invention that include the step 48 may be provided with a flat surface as opposed to the declined surface 43 illustrated while still providing advantages where skirting or boxing is applied in situ. [0047] Unless the context requires otherwise or specifically stated to the contrary, integers, steps or elements of the invention recited herein as singular integers, steps or elements clearly encompass both singular and plural forms of the recited integers, steps or elements. [0048] Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated step or element or integer or group of steps or elements or integers, but not the exclusion of any other step or element or integer or group of steps, elements or integers. Thus, in the context of this specification, the term “comprising” is used in an inclusive sense and thus should be understood as meaning “including principally, but not necessarily solely”. [0049] It will be appreciated that the foregoing description has been given by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons of skill in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.

A floor coving comprising: a vertical section that in use abuts a vertical structure; a horizontal section that in use abuts a floor extending from said vertical structure; and a concave surface extending between the vertical section and the horizontal section, said concave surface being adapted to support a pliable layer of flooring material in use, wherein an upper surface of said vertical section is declined towards said concave surface.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates to a modular decking system that can be assembled and disassembled for reconfiguration, relocation, and expansion; and more particularly relates to a modular decking system comprised of panels that assemble to form a deck, anchors that uniformly bear the weight from the panels, and fastening components that rotatably lock the panels to the anchors and to the surface to restrict lateral movement therebetween. [0003] 2. Description of the Related Art [0004] Installation of permanent decking requires a specialized skill set and is labor intensive, sometimes requiring footings to be dug or other construction. Traditional decks are often constructed to be a fixed in place and cannot be relocated and can only be removed or relocated through destructive means. Although modular decking kits having attachable members are known in the art, they are often fabricated from wooden members which may warp, splinter, or rot. Most modular decking comprises rectangular decking members affixed together on a subgrade, joists, beams or framing to form a larger deck. These members are not easily secured, transported and detached. Maintenance may be required to protect wooden decking from the elements and seal the surface from moisture. Variations in temperature and humidity cause them to expand and contract, which loosens the metal connection hardware. Lumber used in constructing traditional decking is also susceptible to deterioration by mildew, mold, and infestation. [0005] In many instances, modular decking is not efficient or easily assembled in the construction of a decking. What is needed in the art is a multipurpose, lightweight decking, which does can be easily assembled, disassembled and transported; and which is suitable to withstand inclement weather, harsh environments, heavy foot traffic, and is resilient when exposed to harsh cleaning chemicals. This modular decking should also provide lateral support, comfort, and reduction of fatigue during walking or standing by users of the tile. [0006] It is therefore desirable that a multi-configurable modular decking system be provided which overcomes these difficulties. SUMMARY OF THE INVENTION [0007] From the foregoing discussion, it should be apparent that a need exists for a modular decking system having unique and multi-configurable panels, anchors, locking components. [0008] Beneficially, such a system would overcome many of the difficulties of the prior art by providing a modular decking system comprised of panels that assemble to form a deck, anchors that uniformly bear the weight from the panels while anchored into a ground or wall surface, and fasteners that rotatably lock the panels to the anchors to restrict lateral movement therebetween. The system leverages the weight of the panels, frictional forces, and fastening components to restrict lateral movement between the panels, the anchor, and a surface. [0009] The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available apparatii and methods. Accordingly, the present invention has been developed to provide a modular decking apparatus that assembles to form a deck, the deck being disassemblable and portable, the decking system comprising: a plurality of hexagonal panels having a planar top surface, each panel defining six recesses circumscribing the top surface at evenly-spaced intervals, wherein each recess is shaped as a circular sector, each recess for receiving a fastener; wherein each panel further defines a plurality of apertures on the top surface; the panel further comprising an anchor affixed to a bottom surface of the panel, the anchor comprising: a plurality of fastener receptacles, each fastener receptacle having a foot for engaging a ground surface which protrudes downwardly, each fastener receptacle circumscribing an outside edge of the anchor at evenly-spaced intervals, each fastener receptacle disposed beneath a recess; a plurality of reinforced ribs disposed beneath the bottom surface, the plurality of reinforced ribs configured to enhance structural integrity of the panel; each fastener receptacle comprising an upwardly-protruding locking protrusion for engaging a fastener, the locking protrusion defining at least one locking hole; and a plurality of fasteners, each fastener for interconnecting a plurality of panels, each fastener locking over locking protrusions on separate panels. [0010] The apparatus of claim 1 , wherein each fastener comprises a cylindrical base configured to abut a fastener receptacle, the at least one fastener further comprising a cap configured to overlay the base, the cap defining at least one cap hole, wherein the at least one cap hole is configured to align with the at least one locking hole of the locking protrusion from the fastener receptacle for at least partially fastening the at the at least one anchor to the at least one panel. [0011] The plurality of apertures in the at least one panel may be drainage holes for liquid accumulating on the top surface. In some embodiments, the top surface of the anchor engages and contour a bottom surface of the panel. [0012] The panel and anchor may be formed as an integrated piece. The plurality of reinforced ribs may comprise perpendicularly crossing beams. The base may comprise a plurality of detents configured to frictionally engage the locking protrusion of the fastener receptacle. [0013] The cap may be substantially circular in some embodiments. The at least one cap hole may have a hexagonal shape. [0014] The apparatus may further comprise at least one cap fastener configured to pass through the at least one cap hole and the at least one locking hole. [0015] The at least one cap fastener is a bolt in some embodiments. The at least one cap fastener may comprise a cap fastener hole configured to receive an Allen wrench. The cap may define a plurality of teardrop-shaped locking hole. [0016] These features and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS [0017] In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which: [0018] FIG. 1 is a top perspective view of a panel in accordance with the present invention; [0019] FIG. 2 is a top perspective view of a panel mated with an anchor in accordance with the present invention; [0020] FIG. 3 is a bottom perspective view of a panel in accordance with the present invention; [0021] FIG. 4 is a top perspective view of a fastener locking the panel to the anchor in accordance with the present invention; [0022] FIG. 5 is a top perspective view of a fastener having a base and a cap in accordance with the present invention; [0023] FIG. 6 is a top perspective view of a cap for a fastener in accordance with the present invention; [0024] FIGS. 7A and 7B are side perspective views of a cap fastener and an Allen screw in accordance with the present invention; [0025] FIG. 8 is a top perspective view of a self-locking fastener with a self-locking cap removed from a self-locking base in accordance with the present invention; and [0026] FIG. 9 is a top perspective view of a self-locking cap in accordance with the present invention. DETAILED DESCRIPTION OF THE INVENTION [0027] Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. [0028] Furthermore, the described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. [0029] As referenced in FIGS. 1-9 , a modular decking system 100 comprises at least one panel 102 that assembles to form a deck; at least one anchor 114 that mates with the panel 102 to uniformly bear the dead and/or live load weight from the panel 102 while anchored into a ground or wall surface; and at least one fastener 132 that rotatably locks the panel 102 to the anchor 114 to restrict lateral movement therebetween. [0030] The anchors 114 position at a panel periphery 108 on each panel 102 . The generally peripheral positioning of the anchors 114 and interconnections allow for a more uniform weight distribution of a load on the decking. Additionally, the fastener 132 creates a lock through frictional forces while also providing tactile feedback to indicate when the panel 102 and the anchor 114 are locked into place. The fastener 132 also requires minimal special tools or skillset to lock or remove. [0031] In some embodiments, the system 100 comprises at least one panel 102 and at least one anchor 114 that have substantially the same contour shape. The substantially same contour shape enables for intuitive and facilitated mating therebetween. The panel 102 and the anchor 114 interlock together at the panel periphery 108 and at an anchor periphery 122 through at least one fastener 132 . The fastener 132 uses a rotatable locking mechanism having a plurality of detents 140 . The detents 140 create frictional forces against the anchor and the panel to form a snug fit therebetween. The detents 140 also create tactile feedback during rotation of the fastener 130 to indicate when the locking is complete. [0032] The fastener 132 has at least one cap hole 138 that can be aligned with at least one locking hole 130 in the anchor 114 . Once aligned, at least one cap fastener 152 can pass through the holes 130 , 138 to further secure the lock. In this manner, the interlocking connections are doubly secured while still maintaining their simplicity to form the interlocking interaction between panels 102 and anchors 114 . [0033] In some embodiments, the at least one panel 102 forms a substantial portion of the deck's surface. The at least one anchor 114 uniformly supports the dead and/or live load weight from the panel 102 . The points of interconnection where the fasteners 132 lock the panels 102 and anchors 114 occur at the panel recessions 110 a - 110 f and the anchor recessions 124 a - 124 f . Because the interconnections with the anchor 114 occur at the peripheries 108 , 122 , the load on the decking is more uniformly distributed. [0034] Additionally, each panel 102 is secured in place to the anchor 114 by at least one fastener 132 that engages the anchor 114 at a plurality of anchor recessions 124 a - 124 f on the anchor periphery 122 . The fasteners 132 rotatably lock the panel 102 to the anchor 114 through frictional engagement, detents 140 that snap together and provide tactile feedback, and additional fastening components that pass through at least one locking hole 130 at the anchor recessions 124 a - 124 f and at least one cap hole 138 at the fastener 132 . In one embodiment, six anchors 114 support a single panel 102 and any number of adjacent panels 102 . The use of six anchors 114 and six correlating fasteners 132 is consistent with the hexagonal shape of the panel 102 . However, in other embodiments, any number of anchors 114 and fasteners 132 may be used. [0035] As referenced in FIG. 1 , the system 100 comprises at least one panel 102 . The panel 102 is configured to interlock with additional panels 102 to form the decking. In some embodiments, the decking may include a floor decking, a wall, a patio, a pier, or a boat deck. The panel 102 is defined by a panel bottom surface 104 and a panel top surface 106 . The panel 102 may have a generally flat, hexagonal shape. Though in other embodiments, other shapes for the panel 102 may include, without limitation, a pentagonal, cube, triangle, and rectangle shape. Suitable materials for the panel 102 may include, without limitation, composite lumber, polymeric resins, polyvinyl chloride, virgin polyvinyl chloride, virgin/reclaimed polyvinyl chloride mixtures, compression molded rubber, rigid polymers, hard wood, soft wood, and a combination of wood fiber, plastic, and binding agents. [0036] The panel 102 is further defined by a panel periphery 108 having a plurality of panel recessions 110 a - 110 f . The panel recessions 110 a - 110 f may form a substantially half-circle shape at evenly-spaced sections of the periphery of the panel 102 . The at least one panel 102 also includes a plurality of apertures 112 a - 112 c that are efficacious for enabling water, ice, or debris to pass through. One example of the apertures 112 a - 112 c includes drainage or weep holes passing through the panel 102 serve to shed and disperse water from the deck. The plurality of apertures 112 a - 112 c can take any number of shapes, and may be pre-molded, pre-drilled, or otherwise pre-made with the panel 102 . [0037] Turning now to FIG. 2 , the system 100 is shown to include at least one anchor 114 . The anchor 114 is defined by an anchor top surface 116 , an anchor bottom surface 118 , and a cavity (not shown). In some embodiments, the anchor 114 is configured to have substantially the same contour shape as the panel 102 , whereby the panel 102 mates with the anchor 114 . The anchor 114 receives the panel 102 at the anchor top surface 116 , thereby engaging the panel bottom surface 104 . An anchor periphery 122 aligns flush against a panel periphery 108 when the panel 102 and anchor 114 engage. The panel 102 may be secured, via adhesive, molded attachment, or other means, to the anchor 114 , concealing all of its fastening components and substantially all of the panel bottom surface 104 and the anchor top surface 116 . [0038] The anchor 114 is designed to support the panel 102 , maximizing support for the panel 102 and uniformly distributing dead and/or live load weight onto a ground or wall surface. Because the anchor 114 attaches to the panel periphery 108 , specifically at the plurality of panel recessions 110 a - 110 f , the weight on the decking is uniformly distributed. Furthermore, since six anchors 114 may be used, the weight is further distributed, since it is known that the larger the number of supports, the more uniform is the weight distribution. [0039] The anchor 114 fastens to a ground or wall surface at the anchor bottom surface 118 . In some embodiments, the anchor 114 rests on a grade or level surface and is considered a temporary structure, allowing the system 100 to be utilized by more than just building component. [0040] As illustrated in FIG. 3 , the anchor 114 forms a cavity that enables it to be portable and lightweight. To further reinforce the anchor 114 without significantly increasing its weight, the cavity in the anchor 114 is filled with a reticulated structure, such as a plurality of reinforced ribs 120 . The plurality of reinforced ribs 120 are configured to enhance the structural integrity of the anchor 114 . The ribs 120 serve to further distribute the live and dead load weight from the panel 102 to the anchors 114 . The ribs 120 may include a crosslinking series of barriers that fill the cavity. The crosslinking configuration serves to resist lateral and compressive forces that tend to destabilize the anchor 114 . [0041] Those skilled in the art, in light of the present teachings, will recognize that by creating structural integrity in the cavity of the anchor 114 through ribs 120 , rather than filling the cavity with a solid material, the weight of the anchor 114 is reduced while still maintaining strength and stability. Additionally, the reinforced ribs 120 establish an exact, consistently-spaced gap between adjacent panels 102 , allowing for water drainage and air circulation. [0042] The anchor 114 is further defined by a plurality of anchor recessions 124 a - 124 f at the anchor periphery 122 . The anchor recessions 124 a - 124 f have substantially the same contour shape as the panel recessions 110 a - 110 f , thereby enabling a flush surface with the panel periphery 108 while the panel 102 and the anchor 114 are engaged. [0043] Each anchor recession 124 a - 124 f has a fastener receptacle 126 that integrates therein. The fastener receptacle 126 forms a substantially wing shaped extension to the anchor recessions 124 a - 124 f . Due to this unique wing shaped configuration, the fastener receptacle 126 provides a locking surface for the various fastening components to engage. The fastener receptacle 126 forms a stable surface for receiving fastening components. Thus, frictional engagement works with the detents 140 in the fastening components to lock the fastener 132 into the fastener receptacle 126 . [0044] In one embodiment, the fastener receptacle 126 includes a locking protrusion 128 that extends perpendicularly from the fastener receptacle 126 . The locking protrusion 128 provides yet another locking mechanism to secure the fastener 132 to the fastener receptacle 126 . At least one locking hole 130 is disposed to cross transversely across the locking protrusion 128 . The locking hole 130 enables passage of fastening components that help secure the panel 102 to the anchor 114 . [0045] Each fastener receptacle 126 extends transversely across the anchor 114 . The fastener receptacle 126 is disposed to extend beyond the anchor bottom surface 118 . In this manner, the fastener receptacle 126 forms an extension that orients perpendicularly to the anchor 114 . The fastener can be used to penetrate the ground or wall surface for anchoring. For example, six fastener receptacles 126 on the anchor periphery 122 penetrate the ground surface until the anchor 114 is level and stable relative to the ground surface. However in other embodiments, the fastener receptacle 126 may attach to the ground or wall surface through other means, including, without limitation, screws, nails, magnets, ropes, and adhesives. [0046] It is significant to note that the panel 102 and the anchor 114 have a lightweight construction, being made of lightweight plastic or another composite material, with each panel 102 and each anchor 114 manufactured as individual single pieces. One possible form of manufacturing may include injection molding, although compression molding or any other suitable technique for molding polymeric resin may also be used. Additionally, during fabrication, the panel 102 and the anchor 114 may be reinforced by pulling reinforced fibers through the resin. [0047] Turning now to FIG. 4 , the system 100 further comprises at least one fastener 132 that is configured to rotatably fasten against the fastener receptacle 126 at the anchor recessions 124 a - 124 f and the panel recessions 110 a - 110 f . The fasteners 132 serve to restrict lateral movement between the panel 102 and the anchor 114 . The fastener 132 also works with the fastener receptacle 126 for anchoring to the ground or wall surface. In one embodiment, six fasteners 132 engage six fastener receptacles 136 . [0048] FIG. 5 illustrates a perspective close-up view of the fastener 132 . The fastener 132 comprises a base 136 having an elongated shape that is configured to at least partially pass through the fastener receptacle 126 . The base 136 has a plurality of detents 140 configured on the outer surface of the base 136 to provide tactile feedback for when the fastener 132 is rotatably locked to the fastener receptacle 126 . The fastener 132 utilizes frictional engagement and the detents 140 to form a snug fit with the fastener receptacle 126 . In this manner, the panel 102 and the anchors 114 are securely held into place with minimal tools or skillsets needed. [0049] Each fastener 132 passes through the panel recessions 110 a - 110 f and the anchor recession 124 a - 124 f , locking into place with the fastener receptacle 126 by means of a vertical 360° rotation. In one embodiment, detents 140 in the fastener 132 engage depressions in the fastener receptacle 126 . The detents 140 provide tactile feedback once the turn is complete and the fastener 132 is locked into place. In one embodiment, the system 100 utilizes six fasteners 132 to engage six fastener receptacles 126 . Additional fastening components may be used to further secure the fastener 132 to the anchor 114 and the panel 102 . [0050] As shown in FIG. 6 , the fastener 132 comprises a cap 136 that is disposed to overlay the base 136 . The cap 136 comprising at least one cap hole 138 . The cap hole 138 may have a variety of shapes, including, without limitation, circles, tear drops, hexagons, pentagons, and cubes. For example, FIG. 6 illustrates a central hexagonal-shaped cap hole 138 concentric to outer circular and smaller hexagonal holes. The at least one cap hole 138 is configured to align with the locking hole 130 of the protrusion 128 from the fastener receptacle 126 . [0051] Once the cap hole 138 aligns with the locking hole 130 in the locking protrusion 128 , then at least one cap fastener 152 ( FIG. 7A ), such as a screw, bolt, nail, and nut, can pass through the aligned cap hole 138 and the locking hole 130 to fasten the anchor 114 to both the panel 102 and the ground or wall surface. FIG. 7B illustrates an Allen screw 154 , which is an alternative embodiment of the cap fastener 152 . The cap fastener 152 comprises a cap fastener hole 156 that provides a grip for a wrench to rotatably fasten the cap fastener 152 or the Allen screw 154 . It is significant to note that while having small structural differences, both types of cap fasteners 152 , 154 enable rotatable tightening and loosening of the cap 136 relative to the base 136 , and also fasten the fastener 132 to the fastener receptacle 126 . [0052] FIGS. 8 and 9 illustrate an alternative embodiment of a self-locking fastener 142 having a self-locking base 158 with an internal clip 144 to attach a self-locking cap 150 . The clip 144 is disposed inside the self-locking base 158 . As the self-locking cap 150 is rotated, the clip 144 clamps down on a teardrop cap hole 148 on the self-locking cap 150 through a clip slot 160 . The self-locking base 158 comprises a teardrop locking hole 146 that aligns with the teardrop cap hole 148 . Once aligned, the self-locking fastener 142 can be made to attach the fastener receptacle 126 with the cap fastener 152 . It is significant to note however, that the self-locking fastener 142 , though having slightly different mechanisms, operates in substantially the same manner as the fastener 132 discussed above. [0053] In some embodiments, the system 100 utilizes components that are precut and assembled with minimal tools or skillset. The system 100 is efficacious for constructing a solid, yet easily detachable and portable surfaces, for a deck, floor, wall, ceiling, or roof. Those skilled in the art will recognize that the modular, portable capacity of the system 100 provides numerous solutions to decking. [0054] For example, renters, condominium owners, and secondary residences, such as cottages or trailers, can benefit from the interlocking and modular decking system 100 . These users are ideally able to relocate, reconfigure, expand, or store the system 100 , as needed. Additionally, the components of the system 100 are designed to be easily packaged on and within the dimensions of standardized palettes traditionally used for shipping and storage purposes. [0055] Additionally, the universal, interlocking design of the system 100 allows for the addition of accessory components, consisting of, but not limited to: stairways, umbrellas, benches, tables, railings, storage bins, light fixtures, gazebos, planters, and other accessories. The accessories can be supported on the same anchors 114 that support the panel 102 . [0056] During installation of a deck utilizing the system 100 , the area where the installation will take place is preferably level. Where minor discrepancies occur, the length of the fastener receptacles 126 on the anchor recessions 124 a - 124 f can be increased or decreased, as needed. The fastener receptacles 126 from the anchors 114 may then penetrate the ground surface of the designated deck area for preparation to receive the panels 102 . The panel 102 is then attached to the anchors 114 at the panel periphery 108 using the fastener 132 to hold the panels 102 in place against the anchor 114 . The fasteners 132 are inserted into the fastener receptacles 126 of the anchor recessions 124 a - 124 f and rotated up to 360°. A plurality of detents 140 in the base 136 of the fastener 132 provide tactile feedback once the locking rotation is complete and the fastener 132 locked into place. [0057] Additional fastening components, such as screws or bolts, are passed through the locking hole 130 and cap hole 138 to enhance the attachment. Additional anchors 114 may be placed on the ground to receive additional panels 102 . This installation process continues until the desired dimensions of the deck have been completed. The system 100 may be disassembled through simple removal of the fasteners 132 , without requiring excessive force or breakage of the panels 102 or anchors 114 . [0058] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

A portable, modular, interlocking decking system or apparatus that can be assembled and disassembled for resizing, transport, relocation and expansion. The decking comprises a plurality of panels shaped and dimensioned to interlock with other panels via fastener, the fastener comprising an axially rotatable locking mechanism which have detents in some embodiments

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. patent application Ser. No. 13/899,727, filed May 22, 2013, which is a continuation of U.S. patent application Ser. No. 13/010,067, filed Jan. 20, 2011, which is a continuation of U.S. patent application Ser. No. 11/542,753, now U.S. Pat. No. 7,900,402, filed Oct. 4, 2006. BACKGROUND [0002] This disclosure relates to portable seating systems and, more particularly, to a powered telescopic seating riser assembly for a seating system with a multiple of seating configurations drivable between at least an extended position and a stored position. [0003] Seating risers are designed for use in auditoriums, gymnasiums, and event halls to accommodate spectators on portable seats, such as folding chairs. Depending on the intended use, a facility may require seating risers that are capable of being moved from a retracted position for storage, to an extended position for use. [0004] Heretofore, many conventional seating riser structures have been utilized for nonpermanent seating. These conventional systems generally utilize a series of assemblies having seating risers of given heights which store within close proximity to one another. [0005] Because of the temporary nature of the seating used by some organizations and the large storage area required to house non-permanent seating systems when not extended for use, it is desirable to provide a variety of seating configurations with a single non-permanent seating system. With conventional non-permanent seating systems, several assemblies are placed adjacent one another, for instance, to form the seating along an athletic playing surface. Although modular in this sense, conventional non-permanent seating systems have a rise always constant with respect to the run. [0006] Some conventional non-permanent seating systems are manually deployed. Although effective, significant manpower and time is typically required to deploy and store the system. Manual deployment and storage may be further complicated by the requirement that the non-permanent seating system needs to be deployed in a generally coordinated manner, otherwise, binding or other complications may result. Since the non-permanent seating system by its vary nature is a relatively large structure, coordination during manual deployment and storage coordination may be relatively difficult. [0007] Other conventional non-permanent seating systems drive a wheel system thereof. Such drives require friction with a floor surface such that non-uniform traction may also result in the aforementioned binding. SUMMARY [0008] A riser assembly according to an exemplary aspect of the present disclosure includes, among other things, a first skin and a second skin spaced from the first skin. A core is disposed between the first skin and the second skin, the core including a plurality of subpanels. A framework including a plurality of beams is disposed between the first skin and the second skin. The core is received within a space defined by the framework, and a portion of the framework is positioned laterally outside the core. Each of the plurality of subpanels is received within one of a plurality of spaces defined by the framework. The plurality of beams defines a perimeter about each of the subpanels. The first skin, second skin and framework enclose the core. The first skin and the second skin are separate and distinct from the framework. [0009] In a further non-limiting embodiment of the foregoing riser assembly, the first skin includes a first material, the second skin includes a second material, and the core includes a third material different from the first and second materials in composition. [0010] In a further non-limiting embodiment of the foregoing riser assembly, the third material includes an end-grained balsawood. [0011] In a further non-limiting embodiment of any of the foregoing riser assemblies, the core comprises a honeycomb structure. [0012] In a further non-limiting embodiment of any of the foregoing riser assemblies, an access track beam is arranged adjacent to the framework. The access track beam defines a longitudinal slot extending at least partially between each end of the access track beam. The longitudinal slot is configured to selectively receive a mountable accessory. [0013] In a further non-limiting embodiment of any of the foregoing riser assemblies, each of the first and second skins is glued to the core. [0014] In a further non-limiting embodiment of any of the foregoing riser assemblies, each of the first and second skins is attached to the framework. [0015] In a further non-limiting embodiment of any of the foregoing riser assemblies, each of the first and second skins is welded to the framework. [0016] In a further non-limiting embodiment of any of the foregoing riser assemblies, each of the first and second skins has a substantially identical cross-section profile spanning the core and the framework. [0017] In a further non-limiting embodiment of any of the foregoing riser assemblies, the first skin, the second skin and the framework define a first deck surface. The framework extends below a second deck surface vertically spaced from the first deck surface. The framework extends substantially between a front facing edge and a rear facing edge of the second deck surface. [0018] A riser assembly according to another exemplary aspect of the present disclosure includes, among other things, an upper framework and a lower framework spaced vertically relative to the upper framework and extending substantially between a front facing edge and a rear facing edge of the upper framework, and a deck surface. An access beam is exposed. The access beam defines a longitudinal slot together with the upper framework to receive a riser assembly accessory. [0019] In a further non-limiting embodiment of the foregoing riser assembly, the deck surface includes a first skin. [0020] In a further non-limiting embodiment of any of the foregoing riser assemblies, the deck surface is a first deck surface, and a second deck surface is positioned in a stepped arrangement relative to the first deck surface. [0021] In a further non-limiting embodiment of any of the foregoing riser assemblies, the first deck surface is attached to the second deck surface to minimize relative movement therebetween. [0022] In a further non-limiting embodiment of any of the foregoing riser assemblies, the deck surface is attached to the lower framework. [0023] In a further non-limiting embodiment of any of the foregoing riser assemblies, the access track beam is arranged adjacent to the upper and lower frameworks. The access track beam defines a longitudinal slot extending at least partially between each end of the access track beam. [0024] In a further non-limiting embodiment of any of the foregoing riser assemblies, the access track beam is arranged adjacent to the upper and lower frameworks. The access track beam defines a longitudinal slot extending at least partially between each end of the access track beam. [0025] In a further non-limiting embodiment of any of the foregoing riser assemblies, a side of the access track beam is attached to the upper and lower frameworks. [0026] In a further non-limiting embodiment of any of the foregoing riser assemblies, the access track beam defines at least one flange extending inward from the longitudinal slot. [0027] In a further non-limiting embodiment of any of the foregoing riser assemblies, the riser assembly accessory is chair beam mounting system secured to the access beam. [0028] In a further non-limiting embodiment of any of the foregoing riser assemblies, the longitudinal slot is defined by a first channel formed in an upper surface of the access track beam and is also defined by a second channel formed in a lower surface of the upper framework. [0029] In a further non-limiting embodiment of any of the foregoing riser assemblies, the access track beam extends across and is attached to a plurality of ribs extending substantially between the front facing edge and the rear facing edge of the upper framework. [0030] In a further non-limiting embodiment of any of the foregoing riser assemblies, the lower framework extends at least partially below the access track beam. [0031] A method of supporting an accessory relative to a riser assembly according to another exemplary aspect of the present disclosure includes, among other things, selectively attaching an accessory to a longitudinal slot defined by a forward facing access track beam that is positioned in a vertical relationship relative to a first deck panel. The longitudinal slot is also defined by a framework of a second deck panel spaced vertically from the first deck panel. [0032] In a further non-limiting embodiment of the foregoing method includes selectively attaching an accessory to a longitudinal slot defined by a forward facing access track beam that is positioned in a vertical relationship relative to a first deck panel. The longitudinal slot is also defined by a framework of a second deck panel spaced vertically from the first deck panel. [0033] In a further non-limiting embodiment of any of the foregoing methods, the longitudinal slot is defined by a first channel formed in an upper surface of the access track beam and is also defined by a second channel formed in a lower surface of the framework. [0034] In a further non-limiting embodiment of any of the foregoing methods, the longitudinal slot is a first longitudinal slot spaced from a second longitudinal slot also defined by the access track beam. [0035] In a further non-limiting embodiment of any of the foregoing methods, the access track beam is attached to the framework. [0036] In a further non-limiting embodiment of any of the foregoing methods, access track beam is separate and distinct from the framework. [0037] In a further non-limiting embodiment of any of the foregoing methods, the access track beam extends across a plurality of ribs vertically spacing the first deck panel and the second deck panel. [0038] In a further non-limiting embodiment of any of the foregoing methods, each of the plurality of ribs extends substantially between a front facing edge and a rear facing edge of the framework of the second deck panel. BRIEF DESCRIPTION OF THE DRAWINGS [0039] The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows: [0040] FIG. 1 is a perspective view of a non-permanent seating system in a deployed position; [0041] FIG. 2A is an exploded view of a dual deck surface; [0042] FIG. 2B is a perspective view of a frame of the dual deck surface of FIG. 2A ; [0043] FIG. 2C is a sectional view through the dual deck surface illustrating an access track beam; [0044] FIG. 2D is a side view of a section of a non-permanent seating system in a half-deployed position in which only half the seating capacity of each riser assembly is utilized but each seating row provides twice the rise; [0045] FIG. 2E is a perspective view of the non-permanent seating system in a stored position; [0046] FIG. 2F is a perspective view of the non-permanent seating system illustrating one arrangement of rails and stair blocks therefore; [0047] FIG. 3A is a perspective generally bottom view of a single riser assembly; [0048] FIG. 3B is an expanded partially exploded view of a horizontal leg of the telescopic leg assembly of the riser assembly; [0049] FIG. 3C is a perspective generally underside view of the non-permanent seating system in a deployed position illustrating a belt drive system and the interaction of a timing belt between each of the multiple of riser assemblies; [0050] FIG. 3D is a perspective generally rear view of a multiple of the telescopic seat riser systems illustrating the tooth timing belt location; [0051] FIG. 3E is an exploded view of the tooth belt drive system; [0052] FIG. 3F is an exploded view of a guide roller assembly which movably links the riser assembly with the next adjacent riser assembly; [0053] FIG. 3G is a perspective inner view of the locations of the guide assemblies for engagement with a track on an adjacent riser assembly; [0054] FIG. 3H is a view of the tooth belt drive system in an assembled position; and [0055] FIG. 4 is a side view of a section of a non-permanent seating system in a fully deployed position. DETAILED DESCRIPTION [0056] FIG. 1 illustrates a general perspective view of a non-permanent seating system 10 having a multiple of telescopic seating riser systems 12 . The telescoping seating riser system 12 forms the fundamental building blocks of the system 10 . The system 12 may stand alone, or may stand side by side. It will be appreciated that the height thereof is dependent on design choices including the desired rise. [0057] Each telescopic seating riser system 12 generally includes an innermost lower riser assembly 14 , and successive outer elevated riser assemblies 16 - 24 . It will be appreciated that the number of riser assemblies 14 - 24 in any given telescopic seating riser system 12 will be a matter of design requirements. Each riser assembly 14 - 24 generally includes a dual deck surface 26 and a pair of telescopic leg assemblies 28 . [0058] Referring to FIG. 2A , the dual deck surface 26 includes a lower deck surface 30 A and an upper deck surface 30 B arranged in a stepped arrangement. The lower deck surface 30 A and the upper deck surface 30 B each establish a respective deck plane. The dual deck surface 26 generally utilizes a sandwich structure for each deck panel 32 . The deck panel 32 is manufactured of an upper and lower deck skin 34 A, 34 B which sandwiches a core 36 . The skins 34 A, 34 B are preferably manufactured of aluminum while the core 36 is formed of an end-grained balsawood or a honeycomb structure to provide a strong, lightweight and acoustically absorbent structure. The deck panels 32 are mounted to a framework 38 ( FIG. 2B ) which support a multiple of ribs 40 between a set of longitudinal access track beams 42 (also illustrated in FIG. 2C ). The core 36 may include a plurality of subpanels 37 (illustrated in FIG. 2A ) each configured to be received within a space defined by the framework 38 . [0059] The multiple of ribs 40 provide the dual deck surface 26 by vertically separating the lower deck panel 32 L from the upper deck panels 32 U. Each riser assembly 14 - 24 includes one dual deck surface 26 with one lower deck panel 32 L and one upper deck panel 32 U to provide seating on two levels. [0060] Referring to FIG. 2C , the longitudinal access track beams 42 include slots 44 which receive a chair beam mounting system S ( FIG. 2D ) such as that utilized in stadium seating systems such as that manufactured by Camatic Pty Ltd. of Wantirna, Australia. The access track beams 42 are arranged in a vertical relationship between each deck panel 32 L, 32 U to provide space for the seating system 10 when in a stored position. The slots 44 are longitudinally located within the access track beams 42 to provide communication passages for, for example only, aisle lighting, and attachment of, for example only, rails R ( FIG. 2F ), stair blocks B ( FIG. 2F ) and the aforementioned chair beam mounting system S. [0061] Referring to FIG. 3A , each telescopic leg assembly 28 includes a horizontal leg 50 and a vertical leg 52 . It should be understood that although only a single leg assembly will be described, it should be understood that each leg assembly on each dual elevated riser assemblies 14 - 24 is generally alike. Notably, each riser assembly 14 - 24 telescopes under the next higher riser assembly 14 - 24 . [0062] Each vertical leg 52 is attached to the rear of the dual deck surface 26 through a bracket 54 . The vertical leg 52 is preferably manufactured of square tubing, however, other shapes may likewise be usable with the present invention. [0063] A set of rear cross members 56 are connected to the vertical leg 52 at their lower end and to the dual deck surface 26 at their upper end through a central bracket 58 . The rear cross members 56 further stabilizes each riser assembly 14 - 24 . The central bracket 58 is connected to another central bracket 58 ′ on the next riser assembly 14 - 24 through an articulatable linkage 60 which articulates in response to telescopic movement of the riser assemblies 14 - 24 . The linkage 60 preferably provides a passage for the communication of power cables, electronic control and the like. [0064] The horizontal leg 50 is supported on wheels 62 . Preferably, four wheels 62 are mounted within each of the horizontal legs 50 to allow each riser assemblies 14 - 24 to readily travel over a floor surface. [0065] Referring to FIG. 3B , each horizontal leg 50 of each leg assembly 28 supports a toothed belt drive system 64 . The belt drive system 64 includes an electric motor 66 , an inner pulley 68 , an outer pulley 70 and a toothed timing belt 72 therebetween. The toothed belt drive system 64 provides the interface between each adjacent riser assembly 14 - 24 ( FIG. 3C ) and the motive force to extend and retract the riser system 12 in a telescopic manner. The toothed timing belt 72 is continuous in this example. That is, the toothed timing belt 72 is a loop lacking a defined end. [0066] The electric motor 66 is mounted directly aft of the vertical leg 52 in a readily accessible location. Notably, the power cable 67 from the electric motor 66 is preferably threaded through the associated rear cross members 56 to communicate with the central bracket 58 and a controller C preferably on the uppermost riser assembly 24 . [0067] The inner pulley 68 and the outer pulley 70 include a toothed surface to engage the toothed belt with a minimum of slippage. The example toothed surface includes a plurality of vertically extending teeth 73 . The inner pulley 68 and the outer pulley 70 rotate about respective axes generally parallel to the vertical leg 52 . The electric motor 66 includes a shaft 75 directly connected to the inner pulley 68 . The shaft 75 rotates about an axis A that is perpendicular to the direction of movement I of the toothed timing belt 72 . The direction of movement I establishes a belt plane associated with the toothed timing belt 72 . The toothed timing belt 72 preferably faces away from, but is engaged with, each adjacent horizontal leg 50 of the next inner riser assembly 14 - 24 ( FIG. 3D ). That is, the toothed timing belt 72 of the belt drive system 64 on the horizontal leg 50 of the outermost riser assembly 24 faces inward toward its own horizontal leg in direction II. The belt 72 , however, is engaged with the horizontal leg 50 of the next inner riser assembly 22 through a belt clamp 74 ( FIG. 3H ). [0068] The toothed timing belt 72 engages the belt clamp 74 located on an outer surface of the adjacent next inner riser assembly 14 - 24 ( FIG. 3E ). Preferably, the belt clamp 74 is located adjacent the intersection of the horizontal leg 50 and the vertical leg 52 and includes a toothed surface which matches the toothed timing belt 72 for engagement therewith. The belt clamp 74 provides the engagement between the toothed timing belt 72 of the outer next inner riser assembly 14 - 24 with the next inner riser assembly 14 - 24 such that rotation of the toothed timing belt 72 drives the next inner riser assembly 14 - 24 relative the associated outer riser assembly 14 - 24 . [0069] Referring to FIG. 3B , a guide assembly 76 along the length of the horizontal leg 50 further guides the inner riser assembly 14 - 24 relative the associated outer riser assembly 14 - 24 . Preferably, a track 78 and guider roller assembly 80 ( FIG. 3G ) provides an effective low friction interface between one inner riser assembly 14 - 24 and the next associated outer riser assembly 14 - 24 . It should be understood that various guide assemblies 76 may be utilized with the present invention. [0070] In operation, the pair of each electric motors 66 on each riser assembly 14 - 24 are driven simultaneously by the controller C to fully extend the seating riser system 12 from the storage position ( FIG. 2E ). The controller C provides for programmed stops of each riser assembly 14 - 24 such that the telescopic seating system 10 may be readily deployed to the fully extended position ( FIGS. 1 and 4 ) or to the half-deployed position ( FIG. 2D ). The half-deployed position utilizes only half the seating capacity of each riser assembly 14 - 24 but provides twice the rise between each seating row to thereby accommodate particular venues. The controller C also communicates with each motor 66 such that the telescopic seating system 10 can be assured of straight tracking through torque sensing. Furthermore, the belt drive system 64 assures coordinated deployment as the toothed timing belt 72 minimizes the likelihood of slippage. [0071] It will be appreciated that seating system is a load bearing structure intended to hold many people and equipment, such as portable seating, above a floor surface. Therefore, the telescopic seating system is suitably constructed. For instance, the structural members of the telescopic seating system preferably are constructed of thin wall tubing, straight bar stock, right angle bar stock, and plate of suitable materials, for instance, steel, alloy, aluminum, wood or high strength plastics. Components may be joined in any number of conventional manners, such as by welding, gluing or with suitable fasteners. Wheels are preferably of the solid caster type. It will be appreciated that in reference to the wheels, such wheels may be constructed of any device that provides rolling or other relative movement, such as sliding, between respective track surfaces. [0072] It should be understood that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude of the system and should not be considered otherwise limiting. [0073] The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.

A riser assembly according to an exemplary aspect of the present disclosure includes, among other things, a first skin. A second skin is spaced from the first skin. A core is disposed between the first skin and the second skin. A framework is disposed between the first skin and the second skin. A portion of the framework is positioned laterally outside the core. A method of supporting an accessory relative to a riser assembly is also disclosed.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to wood deck construction of the cantilevered, circular, or freeform type. 2. Description of the Prior Art The use of cantilever type wood deck platform construction has existed for many years. Typically this construction utilizes a substructure including inground footings that support the main beams upon which a joist structure is framed. Joists are placed on top of the main beams at intervals, which are usually sixteen inches on center. The joists cantilever past exterior beams commonly a distance of twenty-four inches, which results in a less visible deck substructure. The prior art systems are primarily utilized for large or freestanding deck platforms that by design can not be attached to an adjacent structure by ledger beams do not or can not contain a perimeter flush beam header, or perimeter post support system; or require projection over and beyond a fixed object such as a wall or bulkhead. The use of decks to provide outside areas for asthetic considerations, or for entertainment has greatly expanded in recent years. The desire to provide a deck construction that can accomplish the desired asthetic effect while still maintaining structural integrity and keeping the cost low has proven difficult. In cantilevered framing, the recommended framing configuration includes a perimeter structural member known as a "rim", "band", or "ribbon" joist. When perpendicular to joists the member serves, as a "header" or "trimmer" that ties the individual joists together, and does not significantly contribute to deck surface support. When the member is parallel to internal joists it acts as the exterior structural joist member, which is responsible to carry the deck surface weight on the exterior span. The rim joist may be positioned at an angle to the joists without compromise of strength (when properly supported by beam sub-structure) and with little added carpentry skill. A fascia may be added to the perimeter joist to provide a decorative facade, or a separate structure attached to and utilizing the perimeter joist may function as skirting to elimiate sub-structure visibility. In flush beam deck platform framing, the perimeter member or "header" is the structural beam from which all joists are supported or "hung". The joists are set between beams and normally rest on an attached "ledger" with the flush beam supported by perimeter posts. While both systems serve well for their intended function in the construction of wood platform decks of rectangular or angled perimeter shape, a rigid wood exterior structural member on the flush beam normally precludes its use for circular or freeform shapes that utilize flexible or bent wood members. At present three variations of the construction system utilizing cantilevered joists are available, when a circular or freeform shape is desired. The first method is based on bending the perimeter structural member to the desired shape, and then securing it to the joists that have been pre-cut to perimeter shape. As the perimeter wood member size increases or the radius of the bend decreases, "kerfing" of the member is required. "Kerfing " which involves saw blade cutting of a wood member at prescribed intervals to a partial depth to remove stock and enable wood to become more flexible, of any wood member reduces its structural strength, integrity, and fastening ability. It is very difficult to achieve a true arc or radius, when small dimensions or reverse curves are required, by bending wood intended for strutural members, even when kerfed. Fastening and in place retention of the actual member as well as the fastening of deck surfaces and fascia to this member present equally difficult challenges. Costs in labor and material are unpredictable at best. The second method utilizes lamination, etiher horizontal or vertical, of layers of wood members to achieve the perimeter shape of the deck. Both dimensional requirements and fastening problems exist in this method and the "on site" or "in shop" milling, gluing-up and clamping of perimeter members results in time inefficiency, and extremely high costs of material and labor-supervision. This method is used infrequently for sub-structures. The third and most prevalent method of creating circular or freeform deck shapes as viewed from the deck surface is achieved with the sub-structure constructed in a segmented circle. Short lengths of perimeter joists are set on angles following the exterior radius or arc of the deck surface. This method does not achieve a sub-structure that is aesthetically mated to the circular or freeform surface, and requires the use of extended, unsupported surface overhang, resulting in deck edge instability, and does not achieve a true circular or freeform deck. The deck construction of the invention provides structures built to tru arc configuration, that have high structural integrity, and are of relative low cost, simple construction. SUMMARY OF THE INVENTION This invention relates to cantilevered wood deck construction for circular or freeform decks without the use of bent lumber for rim joists or fascia boards or laminated construction. The deck construction contemplates the use of flat horizontally oriented dimensional wood plates fastened to joists that are backed by solid vertical bridging, which has been fastened to the joists and to the flat plates. Vertical fascia boards are attached to the plates which permits of circular arcs, and of reverse arcs of both large and small radius. If the flat plates are installed parallel to the exterior joists spacer blocks are added to improve stability. The principal object of the invention is to provide deck construction for circular and freeform decks that is cantilevered, and is universal in application to the size, configuration, or combination of the desired arc or radius. A further object of the invention is to provide deck construction in which material and labor are most efficiently utilized, and in which costs can be predictably quantified. A further object of the invention is to provide deck construction that can be easily constructed and reproduced with consistent results. A further object of the invention is to provide deck construction wherein considerable reduction of labor and material can achieved. A further object of the invention is to provide deck construction wherein the use of bent lumber or laminated structural members for rim joists or fascia application have been eliminated. A further object of the invention is to provide deck construction aesthetically pleasing when viewed from both on the deck surface and sub-structure locations. A further object of the invention is to provide deck construction that provides a high degree of structural stability and integrity. Other objects and advantageous features of the invention will be apparent from the description and claims. DESCRIPTION OF THE DRAWINGS The nature and characteristic features of the invention will be more readily understood from the following description taken in connection with the accompanying drawings forming part hereof in which: FIG. 1 is a perspective view of a deck joist framing structure, and which includes the structure of the invention; FIG. 2 is an enlarged exploded portion of FIG. 1 showing details of the deck construction of the invention; and FIG. 3 is an enlarged portion of the deck construction of FIG. 1 illustrating the extended fascia embodiment of the invention. It should, of course, be understood that the description and drawings herein are illustrative merely and that various modifications and changes can be made in the structure disclosed without departing from the spirit of the invention. Like numerals refer to like parts throughout the several views. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularly to the drawings and FIGS. 1 and 2, a prefered embodiment of deck construction is illustrated therein installed in connection with a cantilevered wood deck framing system 10 of well known type. A series of appropriately spaced concrete column footings (not shown) with beam seat anchors or posts (not shown) support the beam structure 11. A joist framing structure 12 of 2×6 inch wood members spaced sixteen (16") inches o.c. (on center) is constructed atop a sub-structure which includes a plurality of exterior beams 11. Additional joists 13 are installed, or joist 14 spacing may be decreased, as required on the exterior parallel joist span to provide a maximum flat (horizontal) plate dimension of eleven (11") inches. The joists 12, 13, 14 are installed to cantilever past the exterior beams 11 so that the joist ends extend past the required perimeter dimension of the desired radius of the circular area to be constructed as established from a fixed centerpoint. Solid blocking 15 is installed preferably by nailing and perpendicular to, and between each joist 12, 13, 14. Blocking runs are located between each beam span with the line of blocking extending from the exterior most joists. Perimeter joists 16 are installed as required to complete the standard joist framing sub-structure for a platform deck. Deck joists 12, 13, 14 in the circular perimeter are marked at the required radius from an established (fixed) center point on the exterior most edge of the circumference and then trimmed square 17. Vertical plate blocking 18, solid blocking adjacent to flat plates, is installed preferably by nailing between joists 12, 13, 14 perpendicular to the joists, and flush with the trimmed end 17 of the joist creating a ninety (90) degree attachment area for flat (horizontal) plates to be described. Vertical plate bridging 19, angled solid blocking adjacent to flat plates is installed preferably by nailing between joists 12, at a 45 degree angle on interior joist spaces exceeding the eleven (11") Inch maximum flat plate dimension. A top flat plate 21 of 2 inch (nominal) thick wood of appropriate dimension is mechanically fastened by nails or screws (not shown) into the joist 12, 13, 14, and the vertical plate blocking 18 previously installed. Fasteners are installed within the required dimension to avoid interference with the outer perimeter. The perimeter radius is marked after installation of all top flat plates 21, and plates 21 are cut to the marked radius dimension. A bottom flat (horizontal) plate 22 is scribed to the dimension of the top flat plate 21 previously installed, and is cut to identical shape, and then affixed as described above. Exterior flat (horizontal) plates affixed to parallel joists and supported by beams, require a stiffener block 23 to be installed after final cutting. The fascia boards 25 are applied preferably by nailing to the upper and lower flat plates 21 and 22 to provide a finish edging covering the exterior joist framing. Referring now more particularly to FIG. 3 another embodiment of the invention is illustrated when it is desired to provide an extended fascia system, which is not supported in the same manner as described above. In this embodiment a stud wall structure 30, consisting of 2×4 inch (nominal) studs placed at regular intervals, usually sixteen inches on center, is affixed to the perimeter deck joists 16, and suspends a bottom skirt wall plate 31 within one or two inches from grade. At the projecting end of each internal joist 12, 13, 14, that contains an upper flat (horizontal) plate 21, 37, forming the circular perimeter of the joist framing; two-two by four inch (nominal) vertical blocking suspends within one to two inches from grade, a bottom flat (horizontal) plate 32 cut to the required radius prior to installation. The vertical blocking 40 is provided and fastened by nails or screws (not shown) to the upper and lower plates 37, 32 as well as to joist 12, 13, 14; for stability and support. Skirt wall siding 33 is affixed to the stud wall system, and upper and lower plates 37, 32 to prevent viewing of the deck sub-structure. A mid-plate rail (not shown) may also be installed on skirting structures over 36" high, if desired. Boards 34 to provide a deck surface 35 are installed onto joists 12, 13, 14 preferably by nailing (not shown) and cut to overhang 1 " past fascia, to complete the deck. It will thus be seen that structure has been described with which the objects of the invention are achieved.

This invention is directed to deck construction for circular freeform wood platform decks, which are of the cantilever type and include perimeter joists which have wood plates fastened thereon cut to the desired radius, with vertical fascia wood strips fastened thereto to form the outside edge of the deck.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application No. 60/486,834, filed Jul. 7, 2003. BACKGROUND OF INVENTION [0002] 1. Field of Invention [0003] The present invention relates to the field of cutting tools, particularly to a device and method to cut a control line downhole in a well. [0004] 2. Related Art [0005] With the advent of intelligent completions, running multiple control lines downhole along completions equipment is common practice. Unfortunate occurrences sometimes require cutting the downhole tubing to retrieve the completion equipment. In those cases, the control lines can complicate the retrieval operations if the control lines are pulled apart above the tubing cut. Ideally, the control lines are cut below the tubing cut to recover as much of the control lines as possible and leave a clean “fish” downhole. [0006] Prior systems use a “splice sub” in which the control lines are anchored above and below the tubing cutting target length. A tubing cutter such as an Explosive Jet Cutter (EJC) is run to target depth and detonated to cut the tubing. Excess impact from the EJC at least partially cuts the control lines. When the tubing is removed, the control lines, if not completed severed, break at the damaged area, leaving the remaining control line portions in the vicinity of the remaining tubing. The remaining tubing is more easily “fished” if it is clear of control line remnants. SUMMARY OF INVENTION [0007] The present invention provides for a cutting device and associated method to cut one or more downhole control lines such that the cut ends of the control lines will not interfere with subsequent fishing operations. BRIEF DESCRIPTION OF DRAWINGS [0008] FIG. 1 shows an exploded perspective view of a cutting tool constructed in accordance with the present invention. [0009] FIG. 2 shows a cross-sectional view of an eccentric embodiment of the cutting tool of FIG. 1 . [0010] FIG. 3 shows a first sectional view of the cutting tool of FIG. 2 . [0011] FIG. 4 shows a second sectional view of the cutting tool of FIG. 2 . [0012] FIG. 5 shows a cross-sectional view of a concentric embodiment of the cutting tool of FIG. 1 . [0013] FIG. 6 shows a first sectional view of the cutting tool of FIG. 5 . [0014] FIG. 7 shows a second sectional view of the cutting tool of FIG. 5 . [0015] FIG. 8 shows a cross-sectional view of an alternate embodiment of the cutting tool of FIG. 1 in which dual tubing is used. [0016] FIG. 9 shows a sectional view of the cutting tool of FIG. 8 . [0017] FIG. 10 shows a cross-sectional view of an alternate embodiment of the cutting tool of FIG. 1 . DETAILED DESCRIPTION [0018] Referring to FIG. 1 , a cutting tool 10 comprises four primary components: a mandrel 12 , a cutting sleeve 14 , a housing 16 , and lugs 18 . FIG. 1 also shows a single control line 19 , though the invention is not limited to just one control line. Other figures (e.g., FIGS. 3 and 4 ) show, for example, five control lines 19 . Control line 19 may be, for example, a hydraulic conduit, an electric cable, a fiber optic cable, or a combination of those, as well as other devices manifested as a relatively small diameter longitudinal line. A seal 21 is mounted near the lower end of mandrel 12 and serves to prevent the upward invasion of dust and debris. [0019] In FIG. 1 , housing 16 is shown retracted from its operational configuration to expose the underlying components. Housing 16 normally encloses mandrel 12 and sleeve 14 . Mandrel 12 provides a tubing cutting target 20 and carries a cutting base 22 near its lower end below target 20 . Base 22 can be integral to mandrel 12 or can be made as a separate component and attached to mandrel 12 . Mandrel 12 mounts at its upper end to an upper end of housing 16 , and at its lower end to a lower portion of a tubing 24 . Housing 16 attaches at its upper end to an upper portion of tubing 24 . Tubing 24 , housing 16 , and mandrel 12 , when so assembled, form a continuous passageway for fluid flow. [0020] Sleeve 14 is carried on the lower end of mandrel 12 and can move in both rotation and translation relative to mandrel 12 and base 22 . The relative motion provides a cutting action. Base 22 and sleeve 14 have mating helical surfaces 28 and each has a longitudinal passageway through its respective sidewall to accommodate control line 19 . Those passageways are initially aligned. Axial holes 31 in mandrel 12 and axial holes 33 in base 22 of FIG. 1 show the passageway openings accommodating control line 19 . [0021] Lugs 18 are carried in slots 26 of sleeve 14 and placed in sliding engagement with the lower end of mandrel 12 . Lugs 18 extend into a groove 29 in the inner surface of housing 16 , linking sleeve 14 to housing 16 while permitting sleeve 14 to rotate relative to housing 16 . A recess 35 in mandrel 12 allows lugs 18 to disengage from housing 16 upon sufficient displacement of sleeve 14 . [0022] In operation, a tubing cutter such as an explosive jet cutter is placed in the vicinity of tubing cutting target 20 . The cutter is actuated to sever mandrel 12 somewhere along the length of target 20 . Once mandrel 12 is severed, the upper portion of tubing 24 is pulled upward by the operator. Because housing 16 is attached to the upper portion of tubing 24 , housing 16 is pulled upward as well. Since lugs 18 extend into groove 29 of housing 16 , sleeve 14 is also pulled upward. Thus, housing 16 provides a mechanical link between the upper portion of tubing 24 (that has now been severed from the lower portion of tubing 24 ) and cutting sleeve 14 to generate the relative motion required for cutting control line 19 . [0023] Helical surfaces 28 between sleeve 14 and cutting base 22 cause sleeve 14 to rotate relative to base 22 when sleeve 14 is pulled upward. The rotational motion advances the cutting edge of sleeve 14 through control line 19 , thereby cutting control line 19 . With sufficient upward travel of cutting sleeve 14 , lugs 18 encounter and retract into recess 35 in mandrel 12 to release housing 16 . [0024] Once housing 16 is released, the upper portion of tubing 24 , along with housing 16 and the upper portion of (severed) mandrel 12 can all be removed from the well. The newly cut end of the upper portion of control line 19 is enclosed inside housing 16 during retrieval. The severed end of the lower portion of control line 19 left in the well is enclosed inside sleeve 14 . The lower portion of tubing 24 remains in the well and the uppermost end of the severed lower portion of mandrel 12 is clear of control lines 19 . Preferably the severed end of mandrel 12 is beveled to allow for easy overshoot. Additionally, the outside diameter of sleeve 14 is preferably small enough to be swallowed up (Le., enclosed and captured), for example, by a burner mill. This allows for removal of the remaining portion of the completion assembly from the well. [0025] FIGS. 2-4 show an embodiment of cutting tool 10 in which the elements are eccentrically aligned. The eccentric design accommodates more or larger control lines 19 . [0026] FIGS. 5-7 show an embodiment of cutting tool 10 in which the elements are concentrically aligned. When requirements permit, a concentric design allows for simpler manufacture. [0027] FIGS. 8-10 show alternative embodiments of cutting tool 10 in which the roles of cutter sleeve 14 and base 22 are reversed. A thrust bearing 36 is placed above cutter sleeve 14 to better allow sleeve 14 to rotate. Base 22 can be integral to mandrel 12 or can be made as a separate component and attached to mandrel 12 . Base 22 and cutter sleeve 14 remain the two arms of the scissors and their helical profiles induce relative rotation between them. They can be manufactured from the same tube to ensure a conformable mating surface. The roles are reversed because the lower portion (base 22 ) is now fixed to mandrel 12 . The upper portion (sleeve 14 ) is now the component that rotates. [0028] FIGS. 8 and 9 show an embodiment in which dual tubing strings are used. Primary string 38 and secondary string 40 mount in a fashion similar to that described above to housing 16 and mandrel 12 . If it becomes necessary to cut control lines 19 , tubing strings 38 , 40 are first cut as before. Gaps in sleeve 14 around string 40 and within housing 16 allow sleeve 14 to rotate, cutting control lines 19 . [0029] FIG. 10 also shows other features such as housing 16 having a channel 41 along its entire length such that housing 16 effectively forms a “C-ring”. That allows control lines 19 to be laid through channel 41 alongside mandrel 12 without regard to alignment holes 31 . Channel 41 in housing 16 is rotated to align with the channels (instead of holes 33 ) in the base 22 and cutter sleeve 14 and control lines 19 are installed through the channels one line at a time. Housing 16 can then be rotated over control lines 19 to protect them from external hazards in the well. To avoid hoop stresses in housing 16 , square threads 42 and square lugs 18 are preferred. Lugs 18 may also need to be spring loaded to insure proper retraction from housing 16 . Base 22 can be restrained by clutch 43 to limit the motion of base 22 to translation only. [0030] Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words “means for” together with an associated function.

The present invention provides for a cutting device and associated method to cut one or more downhole control lines such that the cut ends of the one or more control lines will not interfere with subsequent fishing operations.

You are an expert at summarizing long articles. Proceed to summarize the following text: This application is a file wrapper continuation of prior application Ser. No. 08/206,687, filed on Mar. 4, 1994 now abandoned, which is a continuation of prior application Ser. No. 08/018,642, filed on Feb. 17, 1993 now abandoned, which is a continuation-in-part of prior application Ser. No. 07/810,772 filed Dec. 17, 1991 now abandoned. BACKGROUND OF THE INVENTION The present invention relates to a method and apparatus for hydraulic isolation determination of oilfield casings. More specifically, the interfaces between the various materials present in the borehole are interrogated using ultrasonic energies to characterize the materials and the bonds formed between them. In a well completion, a string of casing or pipe is set in a wellbore and a fill material referred to as cement is forced into the annulus between the casing and the earth formation. The primary purpose of the cement is to separate oil and gas producing layers from each other and from water bearing strata. If cement fails to provide isolation of one zone from another, fluids under pressure may migrate from one zone to another, reducing production efficiency. Migration of water, in particular, produces undesirable water cutting of a producing zone and can possibly render a well non-commercial. Also, migration of hydrocarbons into aquifers is environmentally and economically undesirable. It is critical to determine whether the cement is performing its function, i.e., whether the hydrocarbon reservoirs are hydraulically secure. The term "good cement" indicates the adequate separation of zones by the cement, preventing fluid migration between the zones. Cement failures occur in a variety of ways. For example, a complete absence of cement between the casing and the earth formation can occur. This is characterized as a gross cement failure and leads to rapid communication between zones intended to be isolated. Another type of failure arises when channeling occurs within the cement annulus, between the casing and the formation. There are three commonly occurring types of channels. First, a channel which contacts the casing is referred to as a "near channel". Second, a channel which does not contact the casing is referred to as a "far channel" or a "buried-channel". For a buried channel, the region between the channel and the casing is usually cement. And third, a channel occupying the entire space between the casing and the formation is referred to as either a "full channel" or a "traditional channel". All these channels described above are filled with fluids such as mud or gas and all are potential threats to hydraulic isolation. Another condition which occurs, but which is not generally viewed as a cement failure, is known as micro-annulus. This condition occurs when the cement that has filled the annulus is not properly bonded to the casing resulting in a very narrow fluid-filled annulus immediately outside the casing. This annulus is very small and does not affect fluid communication between layers effectively preserving the hydraulic security function of the cement. A completed well includes a number of interfaces at the junctures of the differing materials within the weilbore. A first interface exists at the juncture of the fluid in the casing and the casing itself. The casing is referred to as a first material and is typically made of steel. A second interface is formed between the casing and a second material adjacent to the exterior of the casing. If cement is properly placed between the casing and the formation, providing hydraulic isolation, the second interface exists between the casing (first material) and the cement (second material). Further, a third interface exists between the cement and a third material which is the earth formation. Imperfect cementing operations can result in a variety of interface conditions. A channel contacting the casing results in the second interface being between the casing (first material) and a fluid (second material). In this case, the third interface is formed between a fluid (second material) and the earth formation (third material) where a full channel exists. Alternatively, the third interface is formed between a fluid (second material) and the cement (third material) where a near channel exists. A channel not contacting the casing, results in the second interface being between the casing (first material) and the cement (second material) and the third interface being between the cement (second material) and a fluid (third material). Existence of an interface at the juncture of cement and fluid causes a potential lack of hydraulic isolation. The problem of investigating the fill material or cement outside a casing with a tool located inside the casing has lead to a variety of cement evaluation techniques using acoustic energy. These techniques can be categorized into sonic cement evaluation (SCE) and ultrasonic cement evaluation (UCE). Current sonic cement evaluation can be divided into two distinct categories. The first evaluates the Cement Bond Index (CBI) which attempts to measure the percentage of the circumference of the cement adhering to the casing. The second generates a variable density log which qualitatively evaluates the cement fill in the annulus by identifying a head wave generated by a compressional wave in the formation. Both sonic techniques use non-directional or slightly directional sources and receivers and depend on energy propagation essentially parallel to the surfaces of the casing. One SCE technique is described in U.S. Pat. No. 3,401,773 to Synott, III and assigned to Schlumberger Technology Surveying Corp. Synott describes a cement logging technique using a tool employing a conventional, longitudinally spaced, sonic transmitter and receiver. The signal traveling through the casing is processed and a portion of the signal affected by the presence or absence of cement is extracted. The extracted segment is interrogated to provide a measurement of its energy as an indication of the presence or absence of cement outside the casing. This technique provides useful information about cement defects at the second interface. Current ultrasonic cement evaluation also concentrates on the second interface to determine whether cement or mud is adjacent to the casing in an annulus between the casing and the earth formation. A number of known techniques use a pulse-echo method. A single transducer transmits energy into the casing at near-normal incidence and receives echoes. The signal excites a resonance within the casing and the properties of the resonance are measured and interpreted to indicate whether cement or undisplaced mud lies just outside the casing. The main limitation of such techniques is that they concentrate on the second interface ignoring the effects of the third or further interfaces. Ultrasonic pulse-echo techniques for determining the thickness of materials have been extensively proposed in the art. For example, U.S. Pat. No. 2,538,114 to Mason describes an apparatus for measuring the thickness of a material by noting its resonance frequency whenmaterial is irradiated with ultrasonic energy. In U.S. Pat. No. 4,003,244 to O'Brien, et al., the thickness of a material is measured by employing a pulse echo technique. U.S. Pat. No. 4,255,798 to Havira describes methods and apparatuses for acoustically investigating a casing in a borehole to determine whether cement is present just outside the casing. Casing thickness is also determined. The techniques employ an acoustic pulse source having a frequency spectrum selected to excite a thickness resonance in the insonified portion of the casing. The thickness resonance exists as acoustic reverberations between the inner and outer walls of the casing, i.e., trapped energy. The duration of the reverberations depends on the rate of acoustic energy leaking into adjacent media. The acoustic return from the casing can be thought of in two distinct portions. The first appears as a large amplitude pulse which represents the energy reflected from the first fluid-steel interface, i.e., the inside surface of the casing. The second appears as a decaying resonance which represents the reverberating energy trapped within the casing that has leaked back into the fluid within the casing. The received acoustic pulse is then processed to determine casing thickness or to evaluate the quality of the cement bond to the casing. SUMMARY OF THE INVENTION The present invention provides a method and apparatus for determining the hydraulic isolation in oilfield casings. Hydraulic isolation determinations are made by considering the entire volume of the annulus between the casing and the earth formation and characterizing the third interface formed at the juncture of a second material contacting the outside of the casing (first material) and a third material adjacent to and outside the second material. Interrogation of the third interface is performed by directing an acoustic pulse at a segment of the casing. This pulse passes through the casing and into the second material. The signal is then reflected from the third interface and passes back through the second material as well as the casing and into the borehole where it is detected. The acoustic investigation is performed by an apparatus comprising a housing, transmission means, receiver means, and processing means. The transmission means are mounted in the housing and introduce acoustic energy as a beam which propagates with substantially constant width in the casing at a predetermined initial angle to a first interface. The predetermined angle is selected such that the shear portion of the acoustic energy in the casing travels along a reflective path and reflects from at least one of a second interface and a third interface, and any compressional portion of the acoustic energy in the casing travels substantially parallel to the first interface. The receiver means, which is mounted in the casing a predetermined distance from the transmission means, detects the shear portion which has traveled along the reflective path and which arrives at the first interface. The receiving means detects no substantial energy resulting from the compressional portion. Processing means generate data determinative of the reflective path traveled by the shear portion and representative of properties of the materials in the borehole. The present technique includes advantages over ultrasonic cement evaluation because it utilizes non-normal propagation, preferably between the compressional and shear critical angles in the casing (intercritical), using a pitch-catch operating mode where the transmitter and receiver are separated from one another. This configuration examines a signal which contains discrete arrivals representing acoustic echoes from distinct interfaces. Processing concentrates on an analysis of each arrival independently of arrivals from other interfaces, rather than on a casing resonance containing all interface echoes, as do UCE techniques. The present technique achieves superior results to sonic cement evaluation because there is a strong radial component of propagation and the transducers are highly directional. The directionality of the transducers distinguishes the method from typical surface seismic techniques which use essentially omni-directional transducers. In addition, the configuration of the transducers is set using a predetermined angular operation for the particular transducers along with predetermined distances between the transducers. The angles of the transducers are chosen to optimize shear signals within the casing and to exclude compressional signals. By concentrating the operation of transmission or reception to a beam of substantially constant width, the reflection path of the shear signals of interest are reduced to a group of signals which uniquely represent the materials and geometries of the borehole, and other signals which create interference are greatly reduced or eliminated. The basic advantage of a hydraulic isolation determination apparatus and method in accordance with the present invention is that the shear signals resulting upon encountering the various interfaces are well separated in time and space. This allows accurate analysis of the individual components of the recorded signals. These components are characterized to provide an indication of the quality of isolation achieved by the fill material or cement outside the casing. Additionally, since shear energy which has interacted primarily with the casing exists as separate components of the resulting signal, casing thickness can be determined. Separation of components is accomplished by configuring the transducers at an angular position, separated by a predetermined distance, and by using compact excitation pulses. Further, compressional signals which can be a source of noise interfering with an accurate signal analysis, are not detected due to the preselected angles and positioning of the transducers. A further understanding of the nature and advantages of the invention may be realized with reference to the remaining portions of the specification and drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional diagram of a completed borehole; FIG. 2 is a schematic diagram of a logging operation; FIGS. 3A and B illustrate a transmitter and a receiver along with the various components of an acoustic signal directed from the transmitter into the wall of the borehole; FIG. 4 is an illustration of the travel paths of acoustic energy components through various materials in the borehole; FIG. 5 is an illustration of acoustic energy arrivals which have traveled along paths in a borehole wherein the acoustic energy is generated by a transducer and received along a line perpendicular to the wall of the borehole; FIGS. 6A-6C are illustrations of various embodiments of an apparatus for interrogating the interfaces in a borehole; FIG. 7 is an illustration of the first and second order, compressional and shear signals propagating in the different media in the borehole; and FIG. 8 is an illustration of an alternative embodiment of a hydraulic solation determination apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a cross-sectional diagram showing materials used in a completed borehole to achieve hydraulic isolation. A borehole 111 is cased with a first material, typically steel pipe 115. Outside and adjacent first material 115 lies second material 119. Second material 119 is usually a fill material, commonly referred to as cement, which is pumped into the annulus between casing 115 and earth formation 117. The cement hydrates to retain casing 115 rigidly in position. More importantly, it completely fills the annulus between casing 115 and earth formation 117 sealing off the hydrocarbon strata from the other layers so that when casing 115 and the cement (second material 119) are subsequently perforated, the hydrocarbons enter directly into casing 115 and migration of fluids between adjacent formation layers is prevented. Fluid 121, usually in the form of mud, is pumped into borehole 111 to the inside of casing 115. This fluid 121 maintains equilibrium in borehole 111 so that pressures exerted by formation 117 do not cause borehole 111 to cave in or blow out. In accordance with the above description of borehole 111, a number of interfaces are formed between the various materials. The first interface 123 exists along the juncture between fluid 121 (usually mud) and casing 115. Ideally, second material 119 in the form of cement completely fills the space between casing 115 and earth formation 117. Such a situation is shown along radial line R g . A second interface 125 is formed between casing 115 and cement and a third interface 127 emphasized by the bold line, exists at the juncture of cement and earth formation 117. Unfortunately, fill material or cement does not always completely fill the space between casing 115 and earth formation 117. When cement does not completely fill the space, three possible conditions arise. The first condition is shown along radial line R 1 . A near channel 129 exists between casing 115 and cement. Instead of second interface 125 existing between casing 115 and cement, it is formed between casing 115 and the fluid of near channel 129. In such a situation, the fluid of near channel 129 is second material 119. Additionally, instead of third interface 127 existing between cement and earth formation 117, it is formed at the juncture of a fluid (second material 119) and cement. Another type of near channel is shown along radial line R 2 . This near channel is known as a full channel 133 because fluid extends completely across the annulus to earth formation 117. As in the case of near channel 129, full channel 133 also has a second interface between first material 115 and a fluid (second material 119). However, the third interface for full channel 133 is between a fluid and earth formation 117. The third condition occurs when a channel is formed in the space between second material 119 and earth formation 117, i.e. a channel that does not contact first material 115. This condition is shown along radial line R 3 and is referred to as a buried channel 131. For such a channel, second interface 125 is formed between casing 115 and second material 119 (cement), and third interface 127 is formed at the juncture of second material 119 and the fluid of buried channel 131. FIG. 2 is a schematic diagram of a logging operation. Tool or sonde 210 for acquiring acoustic data is located in borehole 111 penetrating earth formation 117. Sonde 210 is preferably lowered in the borehole by armored multiconductor cable 214 and slowly raised by surface equipment 215 over sheave wheel 216 while data measurements are recorded. The depth of the tool is measured by depth gauge 217 which measures cable displacement. Sonde 210 acquires acoustic data by emitting an acoustic pulse and detecting its return waveform. The sonde comprises at least one source or transmitter and at least one detector or receiver. The transmitter produces a pulse upon excitation. The pulse is directed into casing 115 and a resulting signal is detected by the receiver. The return waveforms can be analyzed by the sonde in situ, analyzed by data processor 218 at the surface, or stored, either in the sonde or at the site for analysis at a remote location. FIGS. 3A and B are illustrations of a transmitter 311 and a receiver 331, mounted in the housing of sonde 210. Transmitter 311 and receiver 331 are transducers capable of either transmitting or receiving acoustic energy. Preferably, at least one of the transducers is of the type for operating with acoustic energy which propagates in the form of a beam. If transmitter 311 is of a beam-type, receiver 331 may or may not be a beam-type transducer. The reason for this is that acoustic energy transmitted by transmitter 311 in the form of a beam will arrive at receiver 331 in the form of a beam provided receiver 311 is located in the appropriate position. Alternatively, if transmitter 311 is a point source, as long as receiver 331 is a beam-type and is positioned appropriately, it will detect a beam of acoustic energy which has traveled along a path of interest. Of course, if both transmitter 311 and receiver 331 are beam-type transducers, the apparatus will function in accordance with the invention. The various paths of components of an acoustic signal detected at receiver 331 are also shown in FIGS. 3A and B. Transmitter 311 transmits a pulse of acoustic energy 313. When transmitter 311 transmits acoustic energy 313 in the form of a beam it does so at a selected transmission angle t to first interface 123 with a width roughly the same as transmitter 311. When pulse 313 strikes casing 115, some of the energy D is reflected while the remainder continues into casing 115. Transmission angle t is selected such that the shear energy continuing into casing 115, does so at a well-defined angle θ from first interface 123. Preferably, angle t is between the compressional critical angle and the shear critical angle for casing 115, providing a strong shear component transmitted into casing 115 while providing no substantial compressional component. Any compressional component which does enter casing 115 travels substantially parallel to the casing interfaces within casing 115. In FIG. 3A, shear component 315 passes through casing 115 and strikes second interface 125 at the back of casing 115. A portion of its energy 317 is reflected while the remainder is transmitted into second material 119. If second material 119 is cement, the remaining portion of shear component 315 is split into two cement components. The first cement component is a shear component 319. The second cement component is a compressional component 321. Each of these components propagates across the cement and is partially reflected at third interface 127. At this point, each component is again split into two reflected components referred to as Third Interface Echoes (TIE's) which propagate back towards casing 115. Upon reflection from third interface 127, shear component 319 is split into a reflective shear-shear component 323 and a reflective shear-compressional component 325. Additionally, compressional component 321 is split into a compressional-shear component 327 and a compressional-compressional component 329 upon reflection from third interface 127. Each of the four TIE's 323, 325, 327, and 329 propagate back through second material 119 to second interface 125. Upon reaching second interface 125, the four TIE's continue through casing 115 exiting at first interface 123 into fluid 121. A receiver 331, positioned and angled properly in borehole 111, detects one or more of the components as they propagate through fluid 121. The above description applies to the situation where transmitter 311 transmits a beam of acoustic energy which is received by either a point-source receiver or a beam-type receiver. In the case where transmitter 311 is a point-source transducer, receiver 331 is a beam-type transducer which receives only energy which has traveled along a predetermined predicted path. The four TIE's are each an individual component of the original acoustic energy signal directed into casing 115: The first TEE is shear-shear component 323 of pulse 313 and it is labeled SS; the second TIE is the shear-compressional component 325 of pulse 313 and it is labeled SC; a third TIE is compressional-shear component 327 labeled CS; and the fourth TIE is compressional-compressional component 329 labeled CC. For each of the labels, the first letter indicates the polarization (shear or compressional) on the trip from the second to the third interface, while the second letter indicates the polarization of the trip back from the third interface to the second. Upon receiving TIE's 323-329, processing is performed to characterize the materials in the borehole as a function of the path of the acoustic energy originally introduced at the front surface of casing 115. Given that parameters such as casing thickness, standoff (distance between transducers and first interface) and offset (distance between transducers) positions of transducers 311 and 331, and the properties of fluid 121 and second material 119 are known, the thickness of second material 119 is determined from the travel time of the TIE's. Additionally, properties of the formation are characterized from the amplitude and polarity of the TIE's. The processing must take into account certain "casing" signals which exist upon transmitting acoustic energy 313 from transducer 311 and which are detected at receiver 331. A majority of acoustic energy 313 emitted from transmitter 311 is reflected at first interface 123 before it ever enters casing 115. This energy is shown as direct reflection D. The remaining portion enters casing 115 preferably at angle θ which is less than the compressional critical angle allowing only shear energy 315 to propagate through first material 115. The dominant casing signals which reverberate in casing 115 never propagate beyond second interface 125. They are reflected back into casing 115 at second interface 125. This reflected energy travels through casing 115 reaching first interface 123 where a portion of it forms casing echo S1. The remainder reflects back into casing 115 to repeat the cycle, creating casing echoes S2, S3 . . . , etc. The operation of transducers 313 and 331 to transmit acoustic energy into casing 115 at at angle θ spatially spreads arrival D and casing echoes S1, S2, S3, etc., away from transmitter 311, along casing 115. Properly positioned, receiver 331 receives portions of a limited number of casing echoes S1, S2, S3 etc. but not all of the casing echoes. In FIG. 3, receiver 331 is shown receiving S1 and S2, but not S3, S4, etc. The components of interest, namely the TIE's arrive between S1 and S2 and are detected by receiver 331 as shown in FIG. 3. These components are analyzed without interpreting or subtracting the later casing reverberations produced upon continued reflections between first interface 123 and second interface 125 and which arrive outside the range of reception for receiver 331. FIG. 3B illustrates a compressional portion or wave resulting from original acoustic energy 313, and is indicated by the series of waves 353. Angle t is chosen to provide no substantial compressional component within casing 115. However, as can be seen from this Figure, the compressional portion 353 which does enter casing 115, travels substantially parallel to interfaces 123 within casing 115 and does not reach receiver 331. FIG. 4 is an illustration of waveforms received from two different third interface conditions. Each waveform includes several separate echo arrivals whose labels correspond to those described with reference to FIG. 3A. As can be clearly seen in FIG. 4, the TIE's are separate in time from the casing echo arrivals. In each case, three of the TIE's are visible. CC 329 has a naturally low amplitude due to low transmission coefficients. Further, it is concentrated beyond the range of receiver 331 and is not distinguishable in either waveform. SC 325 and CS 327 occur at the same time and place and are superimposed and indistinguishable. This is the case when the thickness of second material 119 is locally uniform, as it is in FIG. 4. In each case SC+CS is larger than SS 323 for two reasons: First, it is composed of two arrivals; and second, there is less compressional attenuation than shear attenuation in second material 119. The first waveform W 1 corresponds to the situation where buried channel 131 exists adjacent to and outside second material 119 as shown in the corresponding borehole configuration diagram to the right of waveform W 1 . Waveform W 2 represents data taken when there is no buried channel; a third interface 127 exists at the juncture between second material 119 and earth formation 117. Three factors for a particular TIE, e.g., SC+CS, are considered in characterizing the composition of the second material and, in turn, third interface 127. The first factor is delay. Delay provides an indication of the time it takes for an echo to travel through the second material. Therefore, it represents the thickness of the second material. The shorter the distance an echo travels, the sooner it will arrive at receiver 331. For W 1 , each of the TIE's is sooner than in the case of W 2 . The reason for the earlier arrivals in waveform W 1 is due to the existence of buried channel 131. The thickness of buried channel 131 between second material 119 and earth formation 117 causes third interface 127 to be closer to casing 115 for waveform W 1 . Whereas the first factor, delay of the particular received TIE indicates the distance to third interface 127, the second and third factors provide information related to material properties. The second factor, polarity of a TIE, indicates whether buried channel 131 exists by determining the relative impedance of the materials present along the third interface. A reflection coefficient is computed for third interface 127. The reflection coefficient as calculated is a function of the impedances of the second material and third material as well as other trigonometric functions dependent on the transmission and reflection angles. However, for simplicity, the reflection coefficient may be approximated by the same equations that are used to calculate the reflection coefficient of a signal transmitted at normal incidence: ##EQU1## where R 3 is the reflection coefficient at the third interface; and Z n is the impedance of the nth material. and V n is the velocity of a wave through the nth material; and ρ n is the density of the nth material. An examination of equation (1) reveals that the sign (polarity) of the reflection coefficient is positive (+) when the third material has a higher impedance than the second material. The sign (polarity) is negative (-) when the opposite is true. Typically, cement impedance is higher than that of a gas or undisplaced mud and lower than that of rock. Therefore, when a buried channel is present between the cement and the earth formation, the polarity of the reflection coefficient of the third interface is opposite in sign as compared to that of a third interface where no buried channel exists. In fact, component SC+CS of waveform W 1 and component SC+CS of waveform W 2 have visibly opposite polarities. As a result, the TIE polarities distinguish a formation echo from a buried channel echo. Table 1 below shows the possible interpretations when second material 119 is cement. TABLE 1______________________________________Second ThirdMaterial Material Sign Characterization______________________________________cement mud - Buried channelcement high + Effective isolation impedance formationcement low - False negative isolation impedance formation______________________________________ As can be seen from Table 1, earth formation having an acoustic impedance lower than the cement, e.g. very soft rock, is problematic. This is because it gives a "false negative isolation" characterization. However, since the problem is recognized, it can be anticipated by considering other borehole environment characteristics as measured. The third factor used to characterize the third interface is the amplitude of the TIE. The amplitude of component SC+CS indicates the relative impedances and attenuation coefficients of the different materials. Computation of amplitude is performed in accordance with the following equation: A=|ηe.sup.-α.sbsp.0.sup.l.sbsp.0 T.sub.1 e.sup.-α.sbsp.1.sup.l.sbsp.1 T.sub.2 e.sup.-α.sbsp.2.sup.l.sbsp.2 R.sub.3 | (3) where, A is the amplitude of the spectral representation of a TIE; η is the product of the efficiencies of the transmitter and receiver operating in the borehole fluid, and associated electronics; α 0 is the attenuation coefficient in the borehole fluid; l 0 is the combined propagation length in the borehole fluid, from the transmitter to the casing and from the casing to the receiver, along the TIE's path; T 1 is the product of the transmission coefficients for the TIE as it passes through the first interface in both directions from the borehole into the casing and from the casing into the borehole; α 1 is the attenuation coefficient in the casing; l 1 is the combined propagation length through the casing in both directions along the TIE's path; T 2 is the product of the transmission coefficients for the TIE as it passes through the second interface in both directions from the casing into the annulus, and from the annulus into the casing; α 2 is the attenuation coefficient in the annulus; l 2 is the combined propagation length through the annulus in both directions along the TIE's path; R 3 is the reflection coefficient from the third interface for the TIE; A, η, and the α s are all functions of frequency; and T 1 , T 2 , and R 3 are all functions of the compressional and shear velocities, the densities, and the path's angles in the media, as one skilled in the art will recognize. For example, if the properties of the tool, the borehole fluid, the casing, and the cement are known, then the reflection coefficient from the third interface R 3 can be calculated. If the third interface is the boundary between the cement and formation, R 3 contains information about the formation. To properly configure transmitter 311 and receiver 331 to maximize the sensitivity of the detected signal to the desired interface and minimize the sensitivity to unwanted reflections, e.g. measuring third-interface reflections separated from casing reverberations, a number of parameters must be considered. The transmission and reception angles, the transducer spacing, and the distances from the casing depend on such transducer parameters as angular spectrum, beamwidth, and bandwidth. Also, considerations of the local area of investigation include cement and casing dimensions and acoustic properties, as well as the acoustic properties of the borehole fluid. Many of these parameters depend on one another making optimization of transducer configuration complex. If second material 119 occupies a thick annular space between casing 115 and earth formation 117, the desired TIE may miss a single receiver placed at a particular distance from a single transmitter. One possible solution which anticipates this problem is to alter the relative position of receiver 331 with respect to transmitter 311 based on information obtained by probing the borehole wall. An alternative approach is shown in FIG. 6A. A wider range of coverage is achieved for varying annular thicknesses by employing a group of transmitter-receiver pairs. Preferably, each corresponding pair has a common center point to facilitate processing. Receiver 331A detects TIEs from third interface 127A and originally transmitted by transmitter 311A. Similarly, receiver 331B detects TIEs from third interface 127B and originally transmitted from transmitter 311B. For each transmitter-receiver pair, the spacing is set to capture a time window during which the third interface echoes are expected as calculated for that particular distance range. Detection of a third interface echo with closely spaced pair 311B-331B functions well for formations where the second material is relatively thin. However, this same pair would miss a signal reflected in a formation with a thick second material. Therefore, a wider spaced pair, 311A-331A, is configured with the transducers farther apart. In the embodiment of FIG. 6A, each of transmitters 311 and receivers 331 are located at an equal distance from first interface 123. In an alternative embodiment, shown in FIG. 6B, transmitters 311 are shifted so that the faces of the transmitters lie in a single plane P 1 . In addition, the faces of the receivers 331 are aligned on a single plane P 2 . The advantage of situating transmitters 311 along plane P 1 and receivers 331 along plane P 2 , angled equal but opposite to plane P 1 , is to simplify construction and reduce attenuation in the mud for signals which penetrate deeper into the annulus A third alternative is to use a single transmitter 311 with multiple receivers 331. Such a configuration is shown in FIG. 6C. This configuration gains the advantage of a reduced number of transmitters thereby reducing cost. Of course, a single receiver with multiple transmitters would work equally well. Other configurations may include systems with more than two transmitters and more than two receivers. In addition, the configuration of FIG. 6C may be altered so that receivers 331 are situated along plane P 2 , as in FIG. 6B. Or, multiple transmitters situated along a single plane can be spaced apart from a single receiver. Finally, all transmitters 311 and receivers 331 in the aforementioned configurations can be simulated by one or more phased, delayed, or linear array transducers. In addition to the flexibility of arrays to adapt to various geometries, the arrays allow more control over the apodization of the beams. This is important for maintaining a narrow beam and a narrow angular spectrum. Beam width and angular spectrum are also controlled by transducers which are focused in a variety of geometric configurations, such as conical, spherical, cylindrical, bicylindrical, concave and convex. In the configurations shown in the figures, identical transducers are used for the transmitters and receivers. However, this need not be the case as the angular spectra of each can be chosen independently to achieve an overall angular spectrum. These transducers may be immersion-type, electromagnetic acoustic, or other known transducer formats. FIG. 7 illustrates higher order TIE's which may have potential interest for hydraulic isolation determination. These higher order TIE's are later reverberations of originally transmitted pulse 313 (i.e., casing signals S1, S2, S3, etc.) which produce components similar to components 323-329 of FIG. 3. For example, reverberation S1 produces the following components in second material 119: S1SC 725 and S1CS 727. These two components are reflections from third interface 127 of shear component 719 and compressional component 721 respectively. Components SS and CC are not shown here since they are not as easily detected as arrival SC+CS 731 which propagates back through casing 115 to receiver 331 (not shown). However, SS and CC may be used. The higher order TIE's have larger amplitudes than the first order TIE's and appear at different offsets and delays. Therefore, they are easier to detect and record. However, the disadvantage of using higher order TIE's is that they interrogate more widely separated points on third interface 127 and may suffer greater degradation of resolution and signal reduction. If the annulus between casing 115 and earth formation 117 contains fluid, only one first order TIE occurs, the compressional-compressional component 329. This is because fluids support only compressional waves. The angles and times associated with compressional-compressional component 329 in a fluid-filled annulus are quite similar to those of the shear component 323 in an annulus filled with cement 119. The previous knowledge of the phase of second material 119 against casing 115 aids in interpreting hydraulic isolation determination results. This information is acquired beforehand using standard UCE or from an interpretation of the casing reverberations S1, S2, S3, etc. First material reverberations S1, S2, S3, etc. are all discrete signal components which have interacted, at least once, with both interfaces of the casing. The energy making up S1 travels through first interface 123 from borehole fluid 121. It then follows a path through first material 115 reflecting off second interface 125. It again crosses first material 115 as it follows a path back to first interface 123. The time delay of the arrival of S1, as a result of this travel path, along with the knowledge of some relevant velocities and angles, provides a means of calculating the casing thickness. Also, since S1 has reflected from second interface 125, its amplitude is somewhat dependent on the acoustic impedance of second material 119. Analysis of S1 could provide an indicator of whether second material 119 is a fluid or cement. Analysis for casing thickness or for second material 119 may alternatively be performed using later casing echoes or some combination of casing echoes. FIGS. 3, 4, and 6 illustrate embodiments of the present invention where the transducers are configured to transmit and receive signals along an axial portion of the borehole wall. In FIG. 8, an alternative embodiment is illustrated. Transducers are configured to transmit and receive signals along a circumferential portion of the borehole wall. In this configuration, a signal is transmitted from transmitter 811 into casing 115. Resulting signals from the various interfaces are received by receiver 813. As can be seen from FIG. 8, the angles the signal encounters as it passes through casing 115 and second material 119 and its reflection from the different interfaces is markedly different from those shown in the previous configurations due to the curvature of the borehole wall. The configuration of FIG. 8 makes it easier to assess the effect of out-of-plane rays. The hydraulic isolation determination of the present invention is valuable for two applications in addition to the interrogation of a completed borehole. First, it is useful before fill material is placed in the annulus. This is advantageous because it permits determination of the geometry of the annulus for computing the required volume of cement and provides a baseline for aiding later interpretation. Another advantage obtained by using the invention before cement is pumped into the annulus is the detection of the casing location with respect to the formation. Second, the present invention permits information to be obtained after placement of the fill material and before hydration. The results obtained from these measurements are valuable for hydraulic isolation determination after hydration. In conclusion, the present invention provides new and improved techniques for evaluating and characterizing fill material in the annulus between a casing and an earth formation in a borehole, as well as for determining the casing thickness. While the above is a complete description of the preferred embodiment of the invention, various alternatives, modifications, and equivalents may be used. For example, there is a trade-off between excluding unwanted echoes with a narrower angular spectrum and including wanted echoes with a wider angular spectrum. Therefore, excitation and detection of a carefully chosen and well-defined range of angles is essential. This is achieved by using focused transducers or by choosing the width and bandwidth of the transducer to allow significant diffraction. A number of transducers may affect the desired results including concave spherically-focused transducers, convex, cylindrical, bicylindrical, sonic and electronically focused. Additionally, in the configurations shown in the figures, identical transducers are used for the transmitters and receivers. However, this need not be the case as the angular spectra of each can be chosen independently to achieve an overall angular spectrum. Further, an infinite number of permutations and combinations of the described embodiments are possible including transmitter and receiver assemblies which are neither axially or circumferentially aligned. Another aspect of the invention is its applicability to borehole measurements before hydration of fill material in the annulus between the casing and the earth formation. Such information may be useful for a number of applications. Therefore, the above description should not be taken as limiting the scope of the invention which is defined by the appended claims.

A method and apparatus for determining the hydraulic isolation of layers in an earth formation. The characteristics of various interfaces between the materials in the borehole are evaluated. An acoustic investigation is performed by directing an acoustic signal at a radial segment of the borehole. The signal passes through the casing and the fill material and produces a resulting signal which has travelled along a path encountering various interfaces in the borehole. This signal is processed to make hydraulic isolation determinations.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION The invention relates to a cross member construction for use at the foot of ladders comprising a cross bar fastenable to the sidepieces of the ladder. BACKGROUND OF THE INVENTION A plurality of uses for ladders or ladder elements is known from the state of the art, where the ladder or the ladder element is equipped with additional, supplementing structural elements so that special demands for each use can be met. An important problem in the design of ladders is the reliable setting up or placing of the ladder or of the ladder element. If a ladder is supposed to be utilized on a level, solid ground, problems with respect to setting the ladder up do not exist. Since, however, common use of the ladder requires it to be able to be set up on uneven ground, for example in order to carry out repairs on the outside of a house in order to maintain the outside or for other purposes, it is necessary to design the lower area of the ladder so that it is variable or adjustable in order to facilitate a setting up of the ladder in the vertical direction and to eliminate the risk of tipping. Similar problems exist when ladders must be set up on stairs, for example in order to paint staircases. It is known from the state of the art to provide the sidepieces of the ladder with suitable extensions in order to support, for example, one sidepiece on a lower step while the other sidepiece rests on the next higher step. However, the design of such a ladder is disadvantageous for specific applications, because the ladder stands on the two sidepieces, namely, the support distance corresponds with the distance between the sidepieces. In particular, in the case of a long ladder, there exists the danger that the ladder tilts laterally if it is set up slightly inclined or if the operator bends to the left or right of the central longitudinal axis of the ladder. In order to overcome this disadvantage, a cross member is known which can be fastened to the lower end of the sidepieces of the ladder. The cross member is wider than the distance between the sidepieces so that, as a whole, a safe support results. It is thereby disadvantageous that an adaptation to different heights is possible, or only a limited possibility, in the case of such a cross member since the cross member is usually fastened to the sidepieces of the ladder by means of a clamping device and must be positioned inclined at an angle with respect to the crosspieces of the ladder in order to compensate for an uneven ground. Such inclined positions, in turn, require a corresponding play of the clamping device or an inclined installation of the clamping device. This is not possible, or is only a limited possibility, for structural reasons, since the known cross member can compensate only for small differences in height. SUMMARY OF THE INVENTION The basic purpose of the invention is to provide a cross member construction for a ladder which, with a simple design and simple, reliable handling, enables a compensation for great disparities in levelness and height of the ground support are for the ladder. The purpose is attained according to the invention by the capability of fastening a support element to at least one end region of a cross bar in order to extend the cross bar laterally, which support member has an elevationally adjustable support arm thereon. The foundation for a cross member construction for use on ladders embodying the invention is distinguished by a number of significant advantages. Since the additional support element which is adjustable relative to the cross bar has an elevationally adjustable support arm, the ladder can also be set up in areas having very large disparities in levelness and height. It is thereby particularly important that the cross member construction itself not be adjustable relative to the sidepieces of the ladder so that it is possible to fasten same reliably to the sidepieces of the ladder and to use thereby other clamping or connecting devices, by means of which an exact alignment of the cross member construction is assured. With this adjustment capability, it is particularly assured that unintended incorrect operations of the cross member construction will not occur and that erroneous ladder set ups in an inclined relation, that is, laterally inclined, will also not occur. The foundation of the invention includes an extension of the cross member construction on at least one edge of the ladder, thus achieving a particularly safe support. A particularly favorable design of the invention provides that the support member is constructed like a substantially straight bar, on the free end of which is arranged a support arm. This design enables the use of common, usually extruded profiles and moreover enables the fabrication of the cross member construction such that even an unskilled operator can immediately check the safe handling aspects and the functional aspects of the set up. This is made significantly easier by a straight design of the individual elements, since twistings or the like are not necessary and/or need not be feared. It is furthermore advantageous according to the invention when the support element can be adjustably positioned and fastened to the cross bar by means of a clamping device. A varying width of the cross member construction can be particularly easily realized with this measure, on the other hand, a reliable guiding of the support element on the cross bar of the cross member construction is assured. Furthermore, it is possible to utilize a simple clamping device which, on the one hand, can be manufactured inexpensively and, on the other hand, offers a high degree of reliability in operation. Since the support element and the cross bar are arranged parallel to one another, the forces occurring during use of the ladder do not result in a shifting of the support element relative to the cross bar since the forces are applied substantially perpendicularly with respect to the longitudinal axis of the support element and thus of the cross bar. In order to be able to use the cross bar also without the additional support elements and support arms, the cross bar has a wider width than the distance between the pair of sidepieces on the ladder. It furthermore opens up the possibility of fastening the respective support element to the free end of the cross bar so that the area between the sidepieces does not need to be influenced or occupied by additional fastening devices or the like. Thus, the operator can move on the ladder without any danger because he will not step or get caught on fastening devices. It is furthermore guaranteed thereby that the operator will not unintentionally with his foot release the clamping or fastening devices. A particularly favorable and advantageous type of the clamping device is designed such that same includes an upper and a lower clamping element, each having a U-shaped cross section and being drawn toward one another by means of a screw connection. The clamping elements thus grip around both the cross bar and also the support element and prevent thereby a shifting of the two elements in their longitudinal direction. In addition, both the support element and also the cross bar are mounted so that a lateral slipping is impossible. The support arm utilized to compensate for unlevel support surface conditions is constructed substantially rectilinearly in an advantageous development of the invention and is mounted by means of a guide part fastened on the respective free end of the support element. The support arm is thereby preferably enclosed by a pipe-shaped guide part, so that introduction of force from the support arm onto the support element is safely guaranteed. The support arm must, to adjust the level, merely be moved relative to the guide part. This is a measure which can be taken by an untrained operator without resulting in operating or safety problems. In addition to widening the stance of the ladder through the support elements supported on the cross bar, a further enlargement of the distance between the support points is possible by the support arm extending laterally at the lower end. This modification has furthermore the advantage that a load on the ladder results in a canting of the support arm so that same is additionally secured against a movement relative to the guide part. Thus, and in addition to the clamping action produced by the guide screw, a locking of the support arm occurs. The support arm has at its lower end preferably a support boot which consists, for example, of a rubberlike material in order to prevent a slipping on smooth surfaces. However, it is also possible to design the support boot in its form such that a slipping is prevented, for example, by providing a tip or the like movable into the ground. In order to be able to manufacture the cross member construction of the invention utilizing the simplest initial elements, it is provided that the cross bar, the support element and the support arm have substantially the same hollow rectangular cross section. It is thereby possible to utilize standard dimensions and to fall back on standardized additional elements, for example shields or the like. To safely connect the guide part with the support arm, the invention provides that the guide part has a hole to guide the locking screw therethrough, that the support arm has an elongated slot therein and that inside of the support arm there is arranged a nut, which nut is in engagement with the locking screw and is fixed against rotation. The position of the locking screw is thus predetermined by the hole in the guide part, just like the position of the nut fixed against rotation. The elongated slot enables a movement of the support arm along the guide part and assures at the same time a more reliable and simpler clamping ability. In order to use the cross member construction also when the support elements have been removed, the cross bar has in a favorable development at the outer ends of both cross bars a support boot. Furthermore, it is favorable to fasten the cross bar by means of a clamping device which enables the cross bar to be elevationally adjustable relative to the sidepieces of the ladder in order to assure a variable adaptability of the cross member construction to the ladder. It can furthermore be advantageous according to the invention to provide in addition to the clamping action of the locking screw a positive locking feature. Same can be designed such that on the inner side of the support arm, which inner side opposes the locking screw, there are constructed locking recesses for receiving the free end of a threaded part of the locking screw. The locking recesses can be formed in a perforated bar arranged on the support arm. It is furthermore advantageous when the length of the threaded part is determined such that at a maximum clamping action between a washer and the guide part, the free end of the threaded part extends to a location closely adjacent an inside facing wall of the support arm. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described hereinafter in connection with one exemplary embodiment and the drawings, in which: FIG. 1 is a schematic side view of a partial area of a cross member construction for use on ladders embodying the invention; FIG. 2 is a cross-sectional view taken along the line II--II of the clamping device of the invention; FIG. 3 is a top view of the arrangement shown in FIG. 1, with the support arm being removed; FIG. 4 is a view of the side of the device, which side is the right side in FIG. 1; FIG. 5 is a cross-sectional view of the guide part taken along the line V--V of FIG. 1; FIG. 6 is a simplified side view of a further exemplary embodiment of the support arm of the invention; and FIG. 7 is a cross-sectional view of the exemplary embodiment illustrated in FIG. 6. DETAILED DESCRIPTION FIGS. 1 and 3 each show only a lower region of one of a pair of sidepieces 15 of a ladder. The ladder is designed in the usual manner utilizing metallic hollow profiles. A cross member construction A embodying the invention includes a cross bar 1 fastened to the lower end of each of the two sidepieces 15 by means of a clamping device 14, which clamping device is only schematically illustrated in FIG. 3. The clamping device 14 can include, for example, a clamping jaw and a suitable screw connection. The cross bar 1 has, just like the sidepiece 15, a substantially rectangular hollow profile and is manufactured of an extruded metal material (see FIG. 2). A support boot 13 is mounted on the free right end of the cross bar 1, which free end is oriented laterally outside of the spacing between the pair of sidepieces 15. The support boot 13 serves at the same time as a protective shield. A support element 2 is supported according to the invention parallel to the cross bar 1 on a free end of the cross bar 1 such that the support element is movable parallel to the cross bar 1. A clamping device 4, which will be described in detail hereinafter, is used according to the invention to fix the support element 2 on the bar 1. FIGS. 1 and 3 each illustrate only one half of the cross member construction of the invention, it being understood that same is designed symmetrically, namely, that it is provided on both lateral sides of the ladder. The clamping device 4 of the invention, by means of which the support element 2, which has the same cross section as the cross bar 1 (see FIG. 2), can be connected to the cross bar 1, includes an upper clamping element 5 and a lower clamping element 6. The two clamping elements 5, 6 have each a U-shaped cross section. A screw connection 7 extends through the clamping elements. The two clamping elements 5, 6 can be drawn toward one another by means of the screw connection to clamp the cross bar 1 and support element 2 therebetween, so that a movement of the support element relative to the cross bar is prevented. The U-shaped design of the clamping elements 5, 6 in addition assures also a lateral guiding of the support element 2 on the cross bar 1. FIG. 3 shows that two screw connections 7 are preferred. A guide part 8 is arranged on the free end of the support element 2, which guide part is of a hollow pipe-shaped design and is dimensioned such that a rectilinear support arm 3 can be supported freely movably in the guide part 8. The support arm 3 has at each of its upper and its lower ends a support boot 10 and is held by means of a locking screw 9 in the respective vertically selected position on the guide part 8. The locking screw 9 will be described hereinafter in detail in connection with FIGS. 4 and 5. In order to reduce the risk of possible injuries, the end of the support element 2 which is adjacent the ladder has a cap 16 thereon. FIGS. 4 and 5 illustrate the mechanism of the invention, with the help of which the support arm 3 is fixed on the support element 2. The support arm 3 has an elongated slot 11 extending lengthwise thereof on its one side, through which slot is guided the locking screw 9 into the inside of the support arm 3. The guide part 8 has furthermore a hole 17 therein. Thus, it is possible to move the support arm 3 in longitudinal direction relative to the guide part 8, with the locking screw 9 remaining stationary since it is guided through the hole 17 in the guide part 8. A substantially rectangular washer 18 is arranged inside of the support arm 3, to which washer is connected a nut 12. The nut 12 is threadedly engaged with the locking screw 9. The washer 18 helps to lock the nut 12 against rotation and assures that the locking screw 9 can be tightened without requiring additional, further tools or operations. In order to prevent a complete unscrewing of the locking screw 9, an abutment 19, for example, in the form of a wire bar, is provided at an end of the screw which is inside of the support arm 3 and remote from a handle 9A at its opposite end. FIGS. 6 and 7 show a further exemplary embodiment for fastening the support arm 3 on the guide part 8. The same parts have the same reference numerals. The support arm 3, like in the previous exemplary embodiment, has an elongated slot 11 therein and can be clamped by means of the locking screw 9. The external thread 21 of the locking screw 9 is screwed into an internally threaded hole 23 of the washer 18. The length of the externally threaded part 21A of the screw has a longer length compared with the earlier shown exemplary embodiment. A bar 22 is mounted on the inside of the support arm 3, which bar has locking recesses 20 therein. The locking recesses 20 can be seen in the side view of FIG. 6. FIG. 6 shows a row or arrangement of such locking recesses 20 on the bar 22. Thus, a fine adjustment of the support arm 3 relative to the guide part 8 is possible. The length of the threaded part 21 is such that the free end of the part extends at a maximum clamping action between the washer 18 and the guide part 8 to a location closely adjacent an inside facing wall of the support arm 3. In the exemplary embodiment illustrated in FIGS. 6 and 7, it is possible after releasing the locking screw to cancel the clamping action between the guide part 8 and the washer. This is done by slightly unscrewing the externally threaded part 21A. Due to its length, however, the free end of the externally threaded part 21A continues to be in the corresponding locking recess 20 so that an unintended movement of the support arm 3 relative to the guide part 8 is prevented. Only after the externally threaded part 21 has been further unscrewed does the free end thereof leave the locking recess 20 so that a movement of the support arm 3 relative to the guide part 8 becomes possible. The locking screw is tightened in an analogous manner. Thus, in addition to the force-locking mounting provided by the engagement of the washer 18 with an inside facing wall of the support arm 3, a positive locking of the support arm 3 on the guide part 8 is also guaranteed by the receipt of the free end of the part 21A into a selected recess 20. Thus, it is possible according to the invention to ad]ust the width of the cross member construction A to the respective requirements by moving the support elements 2 relative to the cross bar and, at the same time, to align the ladder by elevationally adjusting the support arm 3 so that the ladder can be set into a vertical alignment on a ground surface having great disparities in levelness. The clamping device 4 enables a movement or fixing of the support elements 2, while the locking screw 9 facilitates the elevational adjustment of the support arm 3.

A cross member construction for use at the foot of ladders having a cross bar fastened to the sidepieces of the ladder and extending laterally outwardly from both side edges thereof. In order to be able to safely set up the ladder on a ground surface having a great disparity in levelness, a support element is fastened to at least one end area of the cross bar to extend the effective length of the cross bar, which support element has an elevationally adjustable support arm thereon.

You are an expert at summarizing long articles. Proceed to summarize the following text: CROSS-REFERENCE TO RELATED APPLICATION This application claims the benefit of U.S. Provisional patent application Ser. No. 60/048,438, filed Jun. 2, 1997. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatically actuated shovel. More specifically, the invention relates to a pneumatically actuated shovel for removing shingles and attached nails from a roof to facilitate re-roofing. 2. Description of Related Art Commonly, when a house or other building has to be reroofed, it is necessary to first remove the existing roof materials. Removing these materials, namely the shingles and nails attaching them to the existing roof structure, is a difficult process which has traditionally been accomplished by forcing a shovel or a similar tool under the shingles to pry them loose along with the attached nails. This requires a great deal of physical exertion and often results in many of the nails either being forcefully ejected from the roof structure so that they pose a danger as they fly through the air or remaining embedded in the roof structure so that they must be removed from the roof structure separately of the shingles. In either case the task of cleaning up the removed roofing materials is made more difficult because the nails have been separated from the shingles while being removed. One way to reduce the effort involved and the tendency of the nails to be separated from the shingles during the removal of the roofing materials is to utilize vibrating or reciprocating and otherwise movable shovel type elements driven by a variety of power sources to pry the shingles and attached nails from the roof structure. A number of tools having shovel type elements of the above described type have been disclosed in the prior art. U.S. Pat. No. 4,095,752, issued Jun. 20, 1978 to Jean-Claude Pomeret and Henry Bonnevaux, discloses a motorized shovel apparatus having a cart mounted swiveling support arm, a pneumatic motor driven winch assembly, and a shovel with a pneumatic vibrator disposed between the handle and the shovel blade. The shovel, which is suspended from the winch assembly on the support arm, has controls in its handle adapted to operate the pneumatic motor driven winch assembly and the pneumatic vibrator so that the shovel may be easily operated with a minimum of physical effort. The apparatus of Pomeret and Bonnevaux is intended to be used to dig holes in the ground in cases where the use of a large mechanical shovel is not economical or is not possible due to lack of space. U.S. Pat. No. 5,009,131, issued Apr. 23, 1991 to Brian J. Alto and Gregory F. Alto, discloses a long handled tool adapted for stripping roof shingles which utilizes a reciprocating blade slidably mounted over a shingle lifting plate to pry shingles from a roof structure and cut the shingle nails. When a trigger on the end of the handle of the tool is squeezed, an electric motor and gearing assembly connected to an offset crank causes the blade to reciprocate along an axis perpendicular to the leading edge of the lifting plate. The tool is effective at removing shingles and nail heads, but leaves the body of the nail embedded in the roof structure. German Patent Number 925,428, issued Mar. 21, 1955, discloses another device which utilizes a motor and gearing assembly connected to an offset crank to reciprocate a blade member in front of the device. U.S. Pat. No. 4,858,503, issued Aug. 22, 1989 to John H. Dike, Jr., discloses a long handled shingle removing tool having a pivoting shovel element on the bottom end of the handle which is actuated by a trigger on the top end of the handle. The shovel element is pivoted upwardly by a pneumatic drive attached thereto to pry the shingles from the roof structure after the shovel element has been forced under a group of shingles. U.S. Pat. No. 5,076,119, issued Dec. 31, 1991 to Steven C. Wenz, discloses a roof shingle removing apparatus having a wheeled shovel like prying member with a blade attached to its forward edge. The blade on the apparatus of Wenz reciprocated along an axis parallel to the leading edge of the shovel like member which is adapted to cut the nail heads to allow the shingles to be easily removed. U.S. Pat. No. 5,098,165, issued Mar. 24, 1992 to James L. Jacobs and Larry D. Rogers, discloses a wheeled cart connected to a roof mounted guide system that allows the roof to be traversed at various positions along different travel paths. The cart has a reciprocating blade attached to its forward edge that follows the contour of the roof structure to dislodge shingles and nails therefrom. The apparatus of Jacobs and Rogers relies on an electric motor to reciprocate the blade and a complicated blade support assembly to insure that the blade follows the contours of the roof structure. German Patent Number 2,300,668, issued Jan. 8, 1974, discloses another device for removing materials from a surface. The device includes a reciprocating plate which pries beneath the surface of the material being removed. The above mentioned device is specifically adapted for removing carpeting from a floor and has a spiked wheel and guide assembly which draws the carpet upward after it has been pried from the floor. U.S. Pat. No. 4,302,894, issued Dec. 1, 1981 to Sam F. Emma, discloses a wheeled device having a long handle extending upward from its base and a movable shovel like member extending forward therefrom. The shovel member on the device of Emma is adapted to pivot downward to dump the material held in the shovel member. U.S. Pat. No. 5,505,340, issued Mar. 19, 1985 to Yantzen et al. and U.S. Pat. No. 3,625,295, issued Dec. 7, 1971 to Samuel D. Gunning, disclose devices having pneumatically driven reciprocating contact elements extending therefrom. Both devices are adapted for breaking up concrete, asphalt, rock and the like in congested areas. However, none of the prior art discloses a shovel having a pneumatically driven reciprocating shovel blade which is specifically adapted to remove roofing shingles and attached nails without separating them from each other. None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. SUMMARY OF THE INVENTION The present invention is a shovel adapted to be used to remove roofing materials with significantly less effort than conventional means and without separating the majority of the nails from the shingles. The shovel comprises a handle, a shovel blade, a trigger mechanism, and an air hammer. The handle is an elongate hollow cylinder having the trigger mechanism attached to its rearward end, the shovel blade attached to its forward end, and an air hose housed therein to connect the trigger mechanism and the air hammer. The shovel blade has a generally flat leading edge adapted for removing roofing materials and a rearward shank. A bracket member, extending rearward from the shovel blade, is adapted to slidably connect the shovel blade and the handle for reciprocal movement of the shovel blade. An air hammer is slidably supported within the bracket. Extending from the forward end of the air hammer is a reciprocating drive rod with a pair of washers encircling its distal end. In order to operate the shovel of the present invention, the trigger mechanism must first be connected to an external pneumatic power source. Then the air hammer may then be actuated by squeezing the trigger mechanism. This causes the washers on the drive rod to contact the shank of the shovel as the drive rod reciprocates, thereby causing the shovel blade simultaneously to reciprocate. Accordingly, it is a principal object of the invention to provide a shovel having a vibrating shovel blade adapted to remove roofing materials. It is another object of the invention to provide a shovel having a vibrating shovel blade driven by an air hammer connected to an external pneumatic power source. It is a further object of the invention to provide a shovel which enhances safety by allowing shingles and nails to be removed from a roof structure without separating the nails from the shingles, thereby eliminating potentially dangerous flying nails. Still another object of the invention is to provide a shovel with a pneumatically driven vibrating blade which is easy to assemble and disassemble for repair and other purposes. It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes. These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the roofing shovel of the present invention. FIG. 2 is a front plan view of the roofing shovel of the present invention with the shovel blade in a normal position. FIG. 3 is a front plan view of the roofing shovel of the present invention with the shovel blade in an extended position. FIG. 4 is an exploded view of a preferred alternative embodiment of a roofing shovel of the present invention. Similar reference characters denote corresponding features consistently throughout the attached drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, FIG. 1 illustrates the pneumatically powered shovel 10 which is intended to be used to remove shingles and nails from an attached roof structure. The shovel 10 includes a handle 90, a shovel blade 20, a trigger mechanism 92, and an air hammer 70, arranged so that the air hammer 70 causes the shovel blade 20 to move rapidly in a reciprocating motion on the forward end of the handle 90 when the trigger mechanism 92 is squeezed. The handle 10 forms an elongate hollow cylinder intended to be gripped adjacent its rearward end and having a bumper 72 made of an elastomeric material fixedly attached to its forward end. The bumper may also be fitted to the air hammer 70. Disposed through the diameter of the handle 90 adjacent its forward end is a removable pin 36 which serves to hold the shovel blade 20 on the handle 90 in a manner to be described hereinafter. Referring now to FIG. 2, the shovel blade 20 is specifically adapted for removing roofing materials in that it has a straight and flat leading edge 22 which is tapered to slide easily under a roof shingle. The leading edge 22 of the shovel blade 20 has a plurality of spaced notches 28 formed therein which may interfit with the shaft of a nail to facilitate its removal. The rearward end of the shovel blade 20 is in the form of a hollow and generally cylindrical shank 24 having a lining 26 made of an elastomeric material. Fixed to the rearward end of the shank 24 are a pair of brackets 40 which extend rearwardly therefrom. Together the brackets 40 define a substantially semicylindrical space which is open at its top side and which has a longitudinally running slot (not shown) along its bottom side, as can be seen in FIG. 2. The brackets 40 are adapted to slidably support the air hammer 70 therebetween. The rearward ends of the brackets 40 are integrally joined together for form a collar 42 having an internal diameter which is slightly larger than the diameter of the handle 90 and slightly smaller than the length of the pin 46. This arrangement allows the collar 42, and thereby the brackets 40 and the shovel blade 20, to be slidably supported on the handle 90 by placing the collar 42 around the forward end of the handle 90 and then inserting the pin 46 through the handle 90 in front of the collar 42 to prevent the collar 42 from sliding off the handle 90. This can also be seen in FIG. 2. The air hammer 70 is placed between the brackets 40 so that the reciprocating drive rod 74 extending therefrom extends into the shank 24. The drive rod 74 has a base portion 76 and a distal end 78 having a smaller diameter than the base portion 76. Secured to the distal end 78 of the drive rod 74 are a pair of washers 80 having an internal diameter slightly greater than the diameter of the distal end 78 of the drive rod 74 and smaller than the diameter of the base portion 76 of the drive rod 74, and having an external diameter larger then the internal diameter of the lining 26 of the shank 24 so that the washers 80 are sandwiched between the base portion 76 of the drive rod 74 and the lining 26 of the shank 24. In order to cause the drive rod 74 of the air hammer 70 to reciprocate, the air hammer 70 must be connected to an external air line A. This is accomplished via the trigger mechanism 92 and an internal air line 96. Referring back to FIG. 1, the trigger mechanism 92, which is fixed to the handle 90 adjacent the rearward end thereof, controls the flow of air from the external air line A into the internal air line 96. Extending from the rearward end of the trigger mechanism 92 is an air inlet 94 adapted to have the external air line A connected thereto. The internal air line 96 leads from the end of the trigger mechanism 92 opposite the air inlet 94, through the interior of the handle 90 to a point above collar 42, where the internal air line 96 exits the interior of the handle 90 to join an L-shaped pneumatic connector 82 adapted to be removably connected to the air hammer 70 through the slot between the bottom sides of the brackets 40. An elastomeric guard 84 is placed around the pneumatic connector 82 at the point where it passes through the slot to prevent unnecessary wear on the pneumatic connector 82. By connecting the air hammer 70 to the external air supply in the above described fashion, the drive rod 74 will reciprocate upon actuation of the trigger mechanism 92 which opens communication between a pressurized air source (i.e., a compressor) and the air hammer 70. Also attached to the rearward end of the handle 90 is a guard 98 and an adjustable valve 100. The guard 98 extends around the trigger mechanism to prevent the accidental actuation thereof and the adjustable valve 100 is connected to the trigger mechanism to regulate the amount of pressurized air may be vented from the trigger mechanism 92. This allows the pressure of the air in the internal air line 96 to be lowered, as desired, from the pressure of the air in the external air line A so that the operation of the air hammer 70 may be adjusted. It should be noted that the shovel 10 may be easily disassembled because the L-shaped pneumatic connector 82 is removably connected to the air hammer 70, the pin 46 is removable, and the air hammer 70, drive rod 74, and washers are not fixed to the brackets 40, the shank 24, or the handle 90. This allows maintenance or replacement of any of the shovel parts to be easily accomplished. Referring now to FIG. 3, the operation of the shovel 10 may be described in the following manner. As the shovel 10 is pressed forward using the handle 90 to wedge the shovel blade 20 between a roof structure and a shingle attached thereto, the forward end of the handle 90 urges the air hammer 70 forward until washers 80 on the distal end 78 of the drive rod 74 are firmly sandwiched between the base portion 76 of the drive rod 74 and the lining 26 of the shank 24. This position is illustrated in FIG. 2 and in dashed lines in FIG. 3. At this point, when the trigger mechanism 92 is actuated, the drive rod 74 will move forward from the air hammer 70, forcing the washers 80 forward against the lining 26 of the shank 24 and thereby urging the shovel blade 20 forward and causing collar 42 to slide forward on the handle 90. This position is illustrated in solid lines in FIG. 3. Then as the drive rod 74 completes its reciprocating motion by moving backward into the air hammer 70, the forward pressure exerted on the handle 90 will cause the collar 42 to slide backward on the handle 90, thereby allowing the handle 90 to urge the air hammer 70 forward relative to the shank 24 until the washers are again firmly sandwiched between the base portion 78 of the drive rod 74 and the lining 26 of the shank 24, thus completing the reciprocating motion of the shovel blade 20. A preferred alternative embodiment of the roofing shovel of the present invention is shown in FIG. 4. As described above, a shovel blade 20 has a leading edge 22 adapted for removing roofing shingles and a rearward hollow shank 24. The bottom of the shovel blade 20 may be provided with a fulcrum 30 which is used in prying operations for greater leverage. The fulcrum 30 may be simply a small beam parallel to the leading edge 22 of the shovel blade on which the shovel blade can pivot. The shank 24 has two longitudinal slots 34 located on the shank 24, 180° from each other. The rearward end of the shank 24 has a reinforced and reduced diameter 26 relative to the rest of the shank 24. The shank 24 is fitted into a separate, singular, and cylindrical bracket 40a. At its forward end, the bracket 40 has a shank receiving collar 44 into which the shank 24 of the shovel blade 20 fits. The shank receiving collar 44 has two apertures, each of which is aligned with one of the slots 34 on the shank 24. A pin 36 passes through one aperture, then through the shank 24, and finally through the other aperture. In this manner, the shovel blade 20 is secured to the bracket 40a such that the blade 20 is free to reciprocate in a longitudinal direction. A spring 32 passes within the shank 24 of the shovel blade 20 connecting a hook on the shovel blade 20 and the pin 36 to bias the shovel blade 20 to a closed position. The reciprocal motion of the shovel blade 20 is once again caused by a drive rod 74 driven by an air hammer 70. The base end 76 of a drive rod 74, broadened by two washers 80, engages the reduced diameter portion 26 of the shovel shank 24. A reduced diameter distal end 78 of the drive rod 74 is seated within and driven by an air hammer 70 which is capped by a bumper 72. When the air hammer 70 is activated, the drive rod 74 is thrust forward, pushing against the shank 24 of the shovel 20, acting against the bias of the spring 32. The entire drive arrangement is housed within the cylindrical bracket 40. The bracket 40 has a removable access panel 48 through which all components of the drive arrangement may be removed and replaced. Opposite the access panel 48 is a cutout for allowing for a connection 82 to an air hose 96 as previously discussed. Also important in this preferred embodiment is a handle receiving collar 42. This collar 42 is an integral part of the bracket 40, found at its rearward end, adapted for receiving the handle 90 to complete the shovel 10. To reduce back strain, this collar 42 is, most preferably, angled slightly upward relative the shank 24 of the shovel blade 20. The attached handle 90 contains an internal air hose 96 and associated parts, as previously discussed. It is to be understood that the present invention is not limited to the embodiment described above, but encompasses any and all embodiments within the scope of the following claims.

An air pressure actuated shovel for removing shingles and attached nails from a roof to facilitate re-roofing. The shovel has an elongated handle with a finger actuated trigger mechanism attached to its top end and a shovel blade supporting an air hammer attached to its bottom. The trigger connects the air hammer and an external pneumatic power source via an air hose inside the handle so that when the trigger mechanism is squeezed, a reciprocating piston, driven by an air hammer, abuts the shovel blade to cause it to vibrate. The vibrating shovel blade effectively loosens shingles and nails from the roof of a building. The removal of shingles with the associated nails intact enhances safety due to the elimination of flying nails.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine such as a hydraulic shovel, and more particularly to a frame constitution of a traveling body in a construction machine. 2. Description of the Related Art A conventional hydraulic shovel 100 disclosed in “Crawler-type Vehicle” (Japanese Unexamined Patent Application Publication 2002-178960) comprises a traveling body 101 to enable movement, and a slewing body 102 which is mounted slewably above the traveling body 101 , as shown in FIG. 9 . The slewing body 102 comprises a slewing frame 103 , and the slewing frame 103 is provided with a body cover 104 accommodating a motor and the like, a cab 105 which defines the operating cabin, a counterweight 106 , and so on, for example. A working device 107 is provided elevatably at the front portion of the slewing body 102 . A truck frame 108 constituting the main body part of the traveling body 101 is, as shown in FIG. 10 , constituted by a center frame 109 positioned in the center by means of steel plate welding or the like, and side frames 112 provided on both the left and right sides of the center frame 109 and extending to the front and rear. Here, the center frame 109 is constituted by a central circular core 110 , and leg parts 111 extending in a front/rear direction and a left/right direction from the outer periphery of the circular core 110 to form an overall H shape. The leg parts 111 are formed as canning structures by an upper plate portion 111 A, a lower plate portion 111 B, side plate portions 111 C which connect the plate portions 111 A, 111 B in a vertical direction, and so on. 112 , 112 are left and right side frames provided on the tip end side of the leg portions 111 of the center frame 109 by welding. The side frames 112 are formed as frame bodies in a substantially reverse C shape extending in a front/rear direction. Left and right mudguard covers 125 , 125 are disposed respectively on the side frames 112 , 112 of the truck frame 108 . Note that “Truck Frame for Construction Machine” (Japanese Unexamined Patent Application Publication H9-202261) is disclosed as another known invention in addition to that described above. The hydraulic shovel 100 described above (see FIG. 9 ) travels over various types of ground by driving crawler belts 117 disposed on the traveling body 101 to rotate. As a result, earth, mud, and so on are churned up by the crawler belts 117 . Here, as shown in FIGS. 9 , 10 , the mudguard covers 125 , 125 provided in the vicinity of the crawler belts 117 , 117 are constituted so as to extend in a horizontal direction, and hence the earth, mud, and so on that are churned up by the crawler belts 117 may accumulate on top of the mudguard covers 125 , 125 . In this case, a worker must remove the accumulated earth, mud, and so on, and if the earth, mud, and so on are left to accumulate, they cause running resistance when the hydraulic shovel 100 is operated. Hence a blade bracket (not shown) on which an earth-removing blade (not shown) is supported so as to swing freely is connected to the front portion of the traveling body 101 . As the blade performs an earth removal operation, various loads such as large loads are applied to the blade bracket which supports the blade. It is therefore desirable that an operating load transmitted to the blade bracket be processed appropriately in order to improve the load-withstanding strength of the vehicle body. SUMMARY OF THE INVENTION The present invention has been designed in consideration of this situation, and it is an object thereof to provide a construction machine which precipitates the removal of earth that is churned up onto a vehicle body from the vehicle body, to reduce the transfer load on a blade bracket, to improve the attachability of the blade bracket, and to achieve standardization of the blade bracket. In a construction machine according to a first invention, a frame of a crawler belt-type traveling body comprises a center frame, a pair of truck frames disposed on an outside of two side portions of the center frame, a connecting member which connects the center frame to the truck frames, and a blade bracket which is joined to the center frame and the connecting member. According to this constitution, the center frame and truck frames are connected by the connecting member, and hence earth that is churned up onto the vehicle body can be caused to drop off the vehicle body favorably. Moreover, the blade bracket is joined to the center frame and connecting member, and hence the width of the blade bracket can be increased. As a result, operating loads acting on the blade can be received on the wide blade bracket, leading to an improvement in the load-withstanding strength. In a construction machine according to a second invention, which pertains to the first invention, a joining face of the center frame to which the blade bracket is joined and a joining face of the connecting member to which the blade bracket is joined form a single plane. According to this constitution, the joining face of the center frame and the joining face of the connecting member to which the blade bracket is joined form a single plane, and hence when joining is performed by welding, straight line welding is possible, thus simplifying the welding operation. In this case, the blade bracket is welded securely to the center frame and connecting member, and hence the joining strength is increased, leading to an improvement in mechanical reliability. Joining is also performed easily when the blade bracket is joined using bolts. Further, since the joining face of the center frame and the joining face of the connecting member to which the blade bracket is joined form a single plane, operating loads acting on the blade can be dispersed smoothly over the vehicle body, leading to an increase in the load-withstanding strength of the vehicle body and an improvement in mechanical reliability. Furthermore, since the joining portion of the blade bracket is planar, the form of the blade bracket can be simplified, leading to a reduction in manufacturing costs. Moreover, the blade bracket, which is joined to a center frame for a large machine model, may also be applied to a center frame for a small machine model, and hence standardization of the blade bracket is achieved. This also contributes to a reduction in the manufacturing costs of the construction machine. In a construction machine according to a third invention, which pertains to the first invention, a joining face of the center frame to which the blade bracket is joined and a joining face of the connecting member to which the blade bracket is joined form a stepped portion. According to this constitution, the center frame and truck frames are connected by the connecting member, and hence earth that is churned up onto the vehicle body can be caused to drop off the vehicle body favorably. Moreover, the blade bracket is joined to the center frame and connecting member, and hence the width of the blade bracket can be increased. As a result, operating loads acting on the blade can be received on the wide blade bracket, leading to an improvement in the load-withstanding strength. In a construction machine according to a fourth invention, which pertains to the first invention, a joining face of the connecting member to which the blade bracket is joined forms a continuous surface such as a curved surface in relation to a joining face of the center frame to which the blade bracket is joined. According to this constitution, the center frame and truck frames are connected by the connecting member, and hence earth that is churned up onto the vehicle body can be caused to drop off the vehicle body favorably. Moreover, the blade bracket is joined to the center frame and connecting member, and hence the width of the blade bracket can be increased. As a result, operating loads acting on the blade can be received on the wide blade bracket, leading to an improvement in the load-withstanding strength. In a construction machine according to a fifth invention, which pertains to any of the first through fourth inventions, the blade bracket is joined to the center frame and connecting member via an attachment member. According to this constitution, the blade bracket is joined to the center frame and connecting member via the attachment member, and hence during the joining thereof by welding, the joining portion of the blade bracket is prevented from being welded to the welding location connecting the center frame to the connecting member. Further, since the blade bracket is joined by welding to the center frame and connecting member via the attachment member, the joining strength of the blade bracket to the center frame and connecting member is increased, leading to an improvement in mechanical reliability. The blade bracket is also joined to the center frame and connecting member via the attachment member when bolts are used therefor, and hence joining is performed easily. Moreover, stress generated by a load that is transmitted from the blade bracket is dispersed upon transmission to the attachment member and then transmitted to the vehicle body, thus heightening the load-withstanding strength of the vehicle body to operating loads generated by the blade, and improving mechanical reliability. A construction machine according to a sixth invention comprises a lower traveling body and an upper slewing body which slews freely in relation to the lower traveling body, a frame of the lower traveling body comprising a hollow center frame to which the upper slewing body is slewably attached, a pair of truck frames disposed on an outside of two side portions of the center frame, a hollow connecting member which connects the center frame to the truck frames, and a blade bracket which is joined to the center frame and the connecting member, the construction machine comprising: the center frame having a joining face at a front thereof to which the blade bracket is joined; and the connecting member having a joining face at a front thereof that is adjacent to the joining face of the center frame so as to form a single plane with the joining face of the center frame, to which the blade bracket is joined, wherein a joining portion of the blade bracket is aligned with the joining face of the center frame and the joining face of the connecting member and welded thereto, whereby the blade bracket is joined to the center frame and the connecting member. According to this constitution, the joining face of the center frame and the joining face of the connecting member, to which the joining portion of the blade bracket is welded, form a single plane, thus enabling straight line welding such that welding can be performed easily. Further, the blade bracket is welded securely to the center frame and connecting member, and hence the joining strength of the welding is increased, leading to an improvement in mechanical reliability. Also, since the joining face of the center frame and the joining face of the connecting member, to which the joining portion of the blade bracket is welded, form a single plane, loads generated by the blade can be dispersed smoothly, leading to an increase in load-withstanding strength and an improvement in mechanical reliability. Further, since the joining portion of the blade bracket can be constituted in planar form, the form of the blade bracket can be simplified, leading to a reduction in manufacturing costs. Also, since the joining face of the center frame and the joining face of the connecting member, to which the joining portion of the blade bracket is welded, form a single plane, the blade bracket, which is joined to a center frame for a large machine model, may also be applied to a center frame for a small machine model, and hence standardization of the blade bracket is achieved. This also contributes to a reduction in the manufacturing costs of the construction machine. A construction machine according to a seventh invention comprises a lower traveling body and an upper slewing body which slews freely in relation to the lower traveling body, a frame of the lower traveling body comprising a hollow center frame to which the upper slewing body is slewably attached, a pair of truck frames disposed on an outside of two side portions of the center frame, a hollow connecting member which connects the center frame to the truck frames, and a blade bracket which is joined to the center frame and the connecting member, the construction machine comprising: a plate-form attachment member to which a joining portion of the blade bracket is welded; the center frame having a joining face at the front thereof to which the plate-form attachment member is welded; and the connecting member having a joining face at a front thereof that is adjacent to the joining face of the center frame so as to form a single plane with the joining face of the center frame, to which the plate-form attachment member is welded, wherein the blade bracket is welded to the center frame and the connecting member via the plate-form attachment member. According to this constitution, the blade bracket is welded to the center frame and connecting member via the attachment member, and hence the joining portion of the blade bracket is prevented from being welded to the location connecting the center frame to the connecting member. Further, the blade bracket is welded to the plate-form attachment member, enabling straight line welding and thus improving weldability. As a result, the joining strength of the blade bracket to the center frame and connecting member is increased, leading to an improvement in mechanical reliability. Furthermore, stress generated by a load transmitted from the blade bracket is dispersed upon transmission to the attachment member, and then transmitted to the vehicle body, and hence the load-withstanding strength in relation to operating loads generated by the blade is increased, leading to an improvement in mechanical reliability. Also, since the joining face of the center frame and the joining face of the connecting member form a single plane, the front plate of the connecting member and the front side plate of the center frame are disposed along the transmission direction of a running load that is transmitted from the connecting member. As a result, running loads are transmitted smoothly from the connecting member to the center frame, thereby contributing to an increase in the load-withstanding strength to running loads and an improvement in mechanical reliability. Further, the attachment member is planar, and hence easy to manufacture, leading to a reduction in costs. A construction machine according to an eighth invention comprises a lower traveling body and an upper slewing body which slews freely in relation to the lower traveling body, a frame of the lower traveling body comprising a hollow center frame to which the upper slewing body is slewably attached, a pair of truck frames disposed on an outside of two side portions of the center frame, a hollow connecting member which connects the center frame to the truck frames, and a blade bracket which is joined to the center frame and the connecting member, the construction machine comprising: an attachment member having a plane to which a joining portion of the blade bracket is welded; the center frame having a joining portion at a front thereof to which the attachment member is welded; and the connecting member having a joining portion adjacent to the joining portion of the center frame to which the attachment member is welded, wherein the blade bracket is welded to the center frame and the connecting member via the attachment member. According to this constitution, the blade bracket is welded to the center frame and connecting member via the attachment member, and hence the joining portion of the blade bracket is prevented from being welded to the location connecting the center frame to the connecting member. Further, the blade bracket is welded to the face of the attachment member, enabling straight line welding and thus improving weldability. As a result, the joining strength of the blade bracket to the center frame and connecting member is increased, leading to an improvement in mechanical reliability. Furthermore, stress generated by a load transmitted from the blade bracket is dispersed upon transmission to the attachment member, and then transmitted to the vehicle body, and hence the load-withstanding strength in relation to operating loads generated by the blade is increased, leading to an improvement in mechanical reliability. In addition, one face of the attachment member is a face to which the joining portion of the blade bracket is welded, and the other face of the attachment member is a face to which the center frame and connecting member are welded, and hence the attachment member is also applicable to a case in which the joining portion of the center frame and the joining portion of the connecting member are formed with a stepped portion, thus enabling greater design freedom. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing a hydraulic shovel of an embodiment according to the present invention; FIG. 2 is a perspective view of a frame of a lower traveling body in the hydraulic shovel of a first embodiment according to the present invention; FIGS. 3A and 3B are a top view of the lower traveling body frame in the hydraulic shovel of the first embodiment according to the present invention, and a sectional view along the A-A line in FIG. 3A ; FIGS. 4A , 4 B, and 4 C are a perspective view showing a center frame of the hydraulic shovel of the first embodiment according to the present invention, a top view of a connecting member 8 r , and a view showing the connecting member 8 r seen from the center frame in the lower traveling body frame shown in FIG. 3A ; FIG. 5 is a perspective view of a frame of a lower traveling body in a hydraulic shovel of a second embodiment according to the present invention; FIGS. 6A and 6B are a top view of the lower traveling body frame in the hydraulic shovel of the second embodiment according to the present invention, and a sectional view along the B-B line in FIG. 6A ; FIGS. 7A , 7 B, and 7 C are a top view showing a first modified example of the joining condition between the center frame, the connecting member, and a blade bracket in the hydraulic shovel of the first embodiment according to the present invention, a top view showing a second modified example thereof, and a top view showing a third modified example thereof; FIGS. 8A , 8 B, and 8 C are a top view showing a fourth modified example of the joining condition between the center frame, the connecting member, and the blade bracket in the hydraulic shovel of the second embodiment according to the present invention, a top view showing a fifth modified example thereof, and a top view showing a sixth modified example thereof; FIG. 9 is a side view showing a conventional hydraulic shovel; and FIGS. 10A , 10 B, and 10 C are a plan view and a perspective view of a truck frame, mudguard covers, and so on in a conventional hydraulic shovel, and a sectional view along the I-I line in FIG. 10A . DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below on the basis of the drawings illustrating embodiments thereof. As shown in FIG. 1 , a hydraulic shovel 1 according to a first embodiment of the present invention comprises a lower traveling body 2 provided with a crawler belt r to enable motion, and an upper slewing body 3 which is attached slewably to the top of the lower traveling body 2 via a slewing bearing (not shown), and which is mounted by an operator to perform an operation. An operating seat 3 a on which the operator sits to perform an operation is provided on the upper slewing body 3 , and a working machine 10 comprising a boom 10 a , an arm 10 b , and an excavating bucket 10 c attached to the tip end of the arm 10 b , which are hydraulically driven, is axially supported in a vertical direction so as to swing freely. In the lower traveling body 2 , a drive shaft 5 and a pivot 6 are attached respectively to the two end portions of truck frames 4 l , 4 r , and the crawler belt r is wrapped around the drive shaft 5 and pivot 6 . Further, a blade B used to rebury earth dredged up by the bucket 10 c is disposed on the front portion of the lower traveling body 2 so as to swing freely about a blade bracket Br (to be described hereinafter), thus enabling the blade B to perform a predetermined operation as an earth-removing plate. Note that when not in use, the blade B is raised as shown in FIG. 1 , and remains so until the beginning of a subsequent operation. When the blade B is used to rebury dredged up earth in this manner, various loads are applied to the blade bracket Br to which the blade B is attached during an operation. The hydraulic shovel 1 constituted as described above is driven by a power source engine, the power of which is converted into oil pressure by a hydraulic pump to drive a traction motor. This causes the drive shaft 5 to rotate, which drives the crawler belt r to rotate, and as a result, traveling is performed and various operations using the bucket 10 c and blade B are performed. As shown in FIG. 2 and the top view of FIG. 3A , a center frame 7 formed with an attachment ring 7 r for attaching a slewing bearing is disposed in the central portion of a frame 2 F of the lower traveling body, and the truck frames 4 r , 4 l are disposed on the two side portions thereof. The truck frame 4 r is connected to the center frame 7 by two leg-shaped connecting members 8 r , 9 r , and the truck frame 4 l is connected to the center frame 7 by two leg-shaped connecting members 8 l , 9 l. These members are joined to each other by welding. The blade bracket Br, to which a hydraulic cylinder for operating the blade B and blade B is attached, is welded to a front face 7 m of the center frame 7 . Note that as shown in FIG. 3A , the truck frame 4 r and the pair of connecting members 8 r , 9 r , and the truck frame 4 l and the pair of connecting members 8 l , 9 l are constituted in plane symmetry about a central face of the center frame 7 in the direction of width (the central line of the center frame 7 in the vertical direction of FIG. 3A ). More specifically, the connecting member 8 r and connecting member 8 l take a symmetrical form about the central face of the center frame 7 in the direction of width, and the connecting member 9 r and connecting member 9 l take a symmetrical form about the central face of the center frame 7 in the direction of width. As shown in FIGS. 2 , 3 , the blade bracket Br comprises a central pair of cylinder fulcrum plates Br 1 which rotatably support a hydraulic cylinder for operating the bracket Br, a pair of right blade fulcrum plates Br 2 and a pair of left blade fulcrum plates Br 3 on the two side portions for rotatably supporting the blade B, and a reinforcing plate Br 4 which is joined to the upper face of the cylinder fulcrum plates Br 1 , the upper face of the right blade fulcrum plates Br 2 , and the upper face of the left blade fulcrum plates Br 3 . These plates are welded to each other to form a subassembly as the blade bracket Br, and then welded to the front face 7 m of the center frame 7 . In the blade bracket Br, rear faces Br 11 of the cylinder fulcrum plates Br 1 , rear faces Br 21 of the right blade fulcrum plates Br 2 , rear faces Br 31 of the left blade fulcrum plates Br 3 , and a rear face Br 41 of the reinforcing plate Br 4 are formed into a vertical plane which constitutes a joining portion that is welded to the front face 7 m of the center frame 7 . Note that as long as the rear faces Br 11 of the cylinder fulcrum plates Br 1 , the rear faces Br 21 of the right blade fulcrum plates Br 2 , the rear faces Br 31 of the left blade fulcrum plates Br 3 , and the rear face Br 41 of the reinforcing plate Br 4 are formed into a single plane, this plane is not strictly limited to a vertical plane. The center frame 7 is manufactured as a cast using cast steel, and as shown in FIG. 4A , is constituted in a hollow box form having a front side plate Ism, a rear side plate 7 su , a right side plate 7 sr to which the connecting members 8 r , 9 r are joined, a left side plate 7 s 1 to which the connecting members 8 l , 9 l are joined, an upper plate 7 u in which the attachment ring 7 r having an opening is formed, and so on. The front face 7 m in the center frame 7 forms a vertical plane which corresponds to the rear faces Br 11 of the cylinder fulcrum plates Br 1 , the rear faces Br 21 of the right blade fulcrum plates Br 2 , the rear faces Br 31 of the left blade fulcrum plates Br 3 , and the rear face Br 41 of the reinforcing plate Br 4 , which serve as the joining portion of the blade bracket Br (see FIGS. 2 , 3 ). By constituting the rear faces Br 11 of the cylinder fulcrum plates Br 1 , the rear faces Br 21 of the right blade fulcrum plates Br 2 , the rear faces Br 31 of the left blade fulcrum plates Br 3 , and the rear face Br 41 of the reinforcing plate Br 4 serving as the joining portion of the blade bracket Br, and the front face 7 m of the center frame 7 serving as the face to which the joining portion of the blade bracket Br is joined, as a vertical plane in this manner, the form of the blade bracket Br and center frame 7 is simplified, and straight line welding can be performed when the blade bracket Br is welded to the center frame 7 . In addition, operations in the design and assembly processes are simplified, which is of course advantageous. Note that as long as the front face 7 m of the center frame 7 , which is the face to which the blade bracket Br is joined, has a planar form which matches the joining portion of the blade bracket Br, then the face is not strictly limited to a vertical plane. The connecting member 8 r is manufactured as a cast using cast steel, and as shown in the top view in FIG. 4B and FIG. 4C (which is a perspective view of the connecting member 8 r alone seen from the side of the center frame 7 shown in FIG. 3A ), is constituted in a hollow form comprising a core portion 8 r 1 having a substantially pentagonal cross section and provided with an angled portion at the upper portion thereof at which a ridge is formed in the longitudinal direction of the upper face, a center joining portion 8 r 2 having a quadrilateral cross section and formed with an opening 8 r 0 , and a truck joining portion 8 r 3 formed with an opening. The center joining portion 8 r 2 of the connecting member 8 r comprises a joining face 8 rb which is joined to the right side plate 7 sr of the center frame 7 , and as shown in FIG. 3 , this joining face 8 rb is formed in planar form to form a straight line when seen from above, and is thus non-perpendicular to the axis which runs along the direction in which the connecting member 8 r extends. Further, the height dimension between the upper and lower faces of the center joining portion 8 r 2 having the joining face 8 rb is set to be slightly shorter than the dimension between the upper and lower faces of the center frame 7 (see FIG. 2 ). A joining face 8 rm which serves as a joining portion with the blade bracket Br is formed on a part of the front face of the connecting member 8 r as a vertical plane corresponding to the rear faces Br 21 of the right blade fulcrum plates Br 2 and the rear face Br 41 of the reinforcing plate Br 4 which serve as the joining portion of the blade bracket Br (see FIGS. 3 , 4 ). Here, when the connecting member 8 r is joined to the center frame 7 such that the central welding portion 8 r 2 of the connecting member 8 r is welded to the right side plate 7 sr of the center frame 7 , the joining face 8 rm of the connecting member 8 r is adjacent to the front face 7 m of the center frame 7 as shown in FIG. 3 , and thus forms a single plane together with the front face 7 m of the center frame 7 . The connecting member 8 l shown in FIGS. 2 , 3 is manufactured as a cast using cast steel, and as described above, is constituted in plane symmetry with the connecting member 8 r about the central face of the center frame 7 in the direction of width. In other words, similarly to the connecting member 8 r , the connecting member 81 is formed as a hollow pipe-form member extending in a longitudinal direction having a closed transverse cross section, and thus takes a similar form to the connecting member 8 r. A joining face 81 m which serves as a joining portion with the blade bracket Br is formed on a part of the front face of the connecting member 8 l as a vertical plane corresponding to the rear faces Br 31 of the left blade fulcrum plates Br 3 and the rear face Br 41 of the reinforcing plate Br 4 which serve as the joining portion of the blade bracket Br. Here, when the connecting member 8 l is joined to the center frame 7 such that a central welding portion 812 of the connecting member 8 l is welded to the right side plate 7 s 1 of the center frame 7 , the joining face 81 m of the connecting member 8 l is adjacent to the front face 7 m of the center frame 7 , and thus forms a single plane together with the front face 7 m of the center frame 7 . Note that as long as the joining faces 8 rm , 8 lm on the connecting members 8 r , 8 l which serve as faces to which the blade bracket Br is joined have a planar form which matches that of the joining portion of the blade bracket Br, then the faces are not strictly limited to vertical planes. As shown in FIGS. 2 , 3 , the connecting member 9 r is manufactured as a cast using cast steel, and is constituted in a hollow form comprising a tapered core portion 9 r 1 having a substantially pentagonal cross section and provided with an angled portion at the upper portion thereof on which a ridge is formed in the longitudinal direction of the upper face, a center joining portion 9 r 2 having a quadrilateral cross section and formed with an opening, and a truck joining portion 9 r 3 formed with an opening. Likewise, the connecting member 9 l is manufactured as a cast using cast steel, and as described above, is constituted in plane symmetry with the connecting member 9 r about the central face of the center frame 7 in the direction of width. As described above, the connecting members 8 r , 8 l , 9 r , 9 l are formed with an angled ridge on the upper face thereof, and hence earth or the like that is churned up by the crawler belt r during traveling slides down the inclined upper surface of the connecting members 8 r , 8 l , 9 r , 9 l and falls onto the ground. Thus earth or the like is prevented from accumulating on the connecting members 8 r , 8 l , 9 r , 9 l. Further, spaces k, k are formed between the connecting members 8 r , 9 r and the connecting members 8 l , 9 l respectively, and hence earth or the like churned up by the crawler belts r, r passes through the spaces k, k and falls onto the ground. Thus earth removal is precipitated favorably. Next, a method of joining the blade bracket Br to the center frame 7 and connecting members 8 r , 9 r will be described. First, the connecting member 8 r is disposed in a central portion in the direction of height in relation to the right side plate 7 sr of the center frame 7 , and in a position at which the front face 7 m of the center frame 7 and the joining face 8 rm of the connecting member 8 r form a single plane, as shown in FIG. 3 , whereupon an outer edge portion of the center joining portion 8 r 2 of the connecting member 8 r is welded to the right side plate 7 sr of the center frame 7 such that the center frame 7 and connecting member 8 r are connected. Similarly, the connecting member 8 l is disposed in a central portion in the direction of height in relation to the left side plate 7 s 1 of the center frame 7 , and in a position at which the front face 7 m of the center frame 7 and the joining face 8 lm of the connecting member 8 l form a single plane, as shown in FIG. 3 , whereupon an outer edge portion of the center joining portion 812 of the connecting member 8 l is welded to the left side plate 7 s 1 of the center frame 7 such that the center frame 7 and connecting member 8 l are connected. By having the joining face 8 rm of the connecting member 8 r form a single plane with the front face 7 m of the center frame 7 , and the joining face 8 lm of the connecting member 8 l form a single plane with the front face 7 m of the center frame 7 in this manner, the center frame 7 and the connecting members 8 r , 8 l are assembled integrally. Next, the rear faces Br 21 of the right blade fulcrum plates Br 2 and a part of the rear face Br 41 of the reinforcing plate Br 4 on the blade bracket Br are aligned with and caused to contact the front face 7 m of the center frame 7 and the joining face 8 rm of the connecting member 8 r which form a single plane, and the rear faces Br 31 of the left blade fulcrum plates Br 3 and a part of the rear face Br 41 of the reinforcing plate Br 4 on the blade bracket Br are aligned with and caused to contact the front face 7 m of the center frame 7 and the joining face 8 lm of the connecting member 8 l which form a single plane, and are thus disposed in a predetermined position. Next, the rear faces Br 21 of the right blade fulcrum plates Br 2 are welded to the front face 7 m of the center frame 7 and the joining face 8 rm of the connecting member 8 r , the rear face Br 41 of the reinforcing plate Br 4 is welded to the front face 7 m of the center frame 7 , the joining face 8 rm of the connecting member 8 r , and the joining face 8 lm of the connecting member 8 l , and the rear faces Br 31 of the left blade fulcrum plates Br 3 are welded to the front face 7 m of the center frame 7 and the joining face 8 lm of the connecting member 8 l. Simultaneously, the rear faces Br 11 of the cylinder fulcrum plates Br 1 are welded to the front face 7 m of the center frame 7 , and thus the blade bracket Br is joined to the front face 7 m of the center frame 7 . According to this constitution, the rear faces Br 21 of the right blade fulcrum plates Br 2 and the rear face Br 41 of the reinforcing plate Br 4 , which serve as the joining portion of the blade bracket Br, form a single plane with the welded front face 7 m of the center frame 7 and the joining face 8 rm of the connecting member 8 r to which the rear faces Br 21 , Br 41 are welded. Further, the rear faces Br 31 of the left blade fulcrum plates Br 3 and the rear face Br 41 of the reinforcing plate Br 4 , which serve as the joining portion of the blade bracket Br, form a single plane with the welded front face 7 m of the center frame 7 and the joining face 8 lm of the connecting member 8 l to which the rear faces Br 31 , Br 41 are welded. Thus straight line welding is possible when welding the blade bracket Br to the center frame 7 and connecting members 8 r , 8 l , making the welding operation easy. Further, since the blade bracket Br is welded securely to the center frame 7 and connecting members 8 r , 8 l , the joining strength is improved, leading to an improvement in mechanical reliability. Moreover, load stress on the blade bracket Br caused by an operation of the blade B is dispersed over the joining locations of the center frame 7 and connecting members 8 r , 8 l which form a single plane, and hence stress concentration does not occur at the planar joining surface, and load stress is dispersed smoothly. Thus the load-withstanding strength of the blade B increases, leading to an improvement in mechanical reliability. Further, the respective joining locations of the center frame 7 and connecting members 8 r , 8 l to which the blade bracket Br is welded form a single plane, and hence a joining portion for the blade bracket Br which forms a single plane can be used, leading to simplification of the form of the blade bracket Br and a reduction in manufacturing costs. Also, since the joining locations of the center frame 7 and the connecting members 8 r , 8 l to which the blade bracket Br is welded form a single plane, a blade bracket with the same dimensions can be used with either a narrow center frame or a wide center frame, and thus a standardized blade bracket having predetermined dimensions can be used regardless of the size of the machine. As a result, the manufacturing costs of the hydraulic shovel can be reduced. Furthermore, since a wide blade bracket Br can be used, the dimension between the right blade fulcrum plates Br 2 and the left blade fulcrum plates Br 3 , the dimension between the cylinder fulcrum plates Br 1 and the right blade fulcrum plates Br 2 , and the dimension between the cylinder fulcrum plates Br 1 and the left blade fulcrum plates Br 3 of the blade bracket Br can each be widened. As a result, operating loads generated by the blade B can be received by the wide blade bracket Br such that the length of the moment lever of the operating load increases, causing the load generated by the moment of the operating load to decrease, and the moment load which acts on the cylinder fulcrum plates Br 1 , right blade fulcrum plates Br 2 , and left blade fulcrum plates Br 3 to decrease. Hence an operating load generated by the blade B that is transmitted to the blade bracket Br decreases, which is effective in preventing wear to the vehicle body and improving the operating performance of the blade B. Note that in the embodiment described above, an example was described in which the front face 7 m of the center frame 7 forms a plane, but as long as at least the joining locations of the blade bracket Br form a single plane, the entire front face of the center frame 7 need not be formed as a plane. Also in the embodiment described above, an example was described in which the blade bracket Br is joined to the center frame 7 and connecting members 8 r , 8 l by welding, but bolts may be used for this purpose instead of welding. In a small hydraulic shovel, depending on the constitution thereof, a location at which the center frame 7 and connecting member 8 r are fillet welded may overlap the outer edge portions of the rear faces Br 21 of the right blade fulcrum plates Br 2 , which serve as welding locations for welding the blade bracket Br to the center frame 7 and so on, and likewise, a location at which the center frame 7 is fillet welded to the connecting member 8 l may overlap the outer edge portions of the rear faces Br 31 of the left blade fulcrum plates Br 3 , which serve as welding locations for welding the blade bracket Br to the center frame 7 and so on. In other words, the welding location of the center frame 7 and the connecting members 8 r , 8 l may match the welding location of the blade bracket Br. In such a case, three members are fillet welded in a single location, leading to problems such as defects in the welding work and a lack of reliability in the welding strength. These problems are solved in the second embodiment to be described below. As shown in FIG. 5 , in the second embodiment, a blade bracket 2 Br is joined to a center frame 7 ′ and connecting members 8 r ′, 8 l ′ via attachment plates Tr, Tl. Apart from this point, the constitution of the second embodiment is identical to that of the first embodiment. Hence identical constitutional elements are illustrated by adding ′ to the same reference symbol, and detailed description of these elements is omitted. As shown in FIGS. 5 , 6 , the blade bracket 2 Br to which a blade B′ and a hydraulic cylinder (not shown) for operating the blade B′ are attached is welded to the front of the center frame 7 ′ and connecting members 8 r ′ and 8 l ′ via the plate form attachment plates Tr, Ti serving as attachment members. As shown in FIGS. 5 , 6 , the blade bracket 2 Br comprises a central pair of cylinder fulcrum plates 2 Br 1 which rotatably support the hydraulic cylinder for operating the blade B', a pair of right blade fulcrum plates 2 Br 2 and a pair of left blade fulcrum plates 2 Br 3 on the two side portions for rotatably supporting the blade B', and a reinforcing plate 2 Br 4 which is joined to the upper face of the cylinder fulcrum plates 2 Br 1 , the upper face of the right blade fulcrum plates 2 Br 2 , and the upper face of the left blade fulcrum plates 2 Br 3 . Here, notch portions 2 Br 41 , 2 Br 41 are formed as joining portions on the rear face 2 Br 42 of the reinforcing plate 2 Br 4 of the blade bracket 2 Br to enable joining to the respective attachment plates Tr, Tl, a notch portion 2 Br 21 is formed as a joining portion on the rear faces 2 Br 2 of the right blade fulcrum plates 2 Br 2 to enable joining to the attachment plate Tr, and a notch portion 2 Br 31 is formed as a joining portion on the rear faces 2 Br 3 of the left blade fulcrum plates 2 Br 3 to enable joining to the attachment plate Tl. Note that the attachment plates Tr, Tl are steel plates of a predetermined size and thickness. The blade bracket 2 Br and attachment plates Tr, Tl constituted as described above are sub-assembled integrally by joining the cylinder fulcrum plates 2 Br 1 , right blade fulcrum plates 2 Br 2 , left fulcrum plates 2 Br 3 , and reinforcing plate 2 Br 4 together by welding, welding the attachment plate Tr to the notch portion 2 Br 41 of the reinforcing plate 2 Br 4 and the notch portion 2 Br 21 of the right blade fulcrum plates 2 Br 2 , and welding the attachment plate Tl to the notch portion 2 Br 41 of the reinforcing plate 2 Br 4 and the notch portion 2 Br 31 of the left blade fulcrum plates 2 Br 3 . In this subassembly, the rear face of the attachment plate Tr is formed as a vertical plane serving as a joining location to which the front face 7 m ′ of the center frame 7 ′ and the joining face 8 rm ′ of the connecting member 8 r ′ are welded, and the rear face of the attachment plate Tl is formed as a vertical plane serving as a joining location to which the front face 7 m ′ of the center frame 7 ′ and the joining face 81 m ′ of the connecting member 8 l ′ are welded. Note that as long as the rear faces of the attachment plates Tr, Tl of the subassembly described above are formed as a single plane, this plane is not strictly limited to a vertical plane. Also, as long as the front face 7 m ′ serving as the joined face of the center frame 7 ′ aligns with the rear faces of the attachment plates Tr, Tl of the subassembly comprising the blade bracket and so on, this face is not strictly limited to a vertical plane. In other words, when the rear faces of the attachment plates Tr, Tl of the subassembly are formed as a plane other than a vertical plane, the front face 7 m ′ of the center frame 7 ′ should be formed as a plane other than a vertical plane which aligns with the plane of the rear faces. Further, the joining face 8 rm ′ serving as a joining portion for the blade bracket Br′ on a part of the front face of the connecting member 8 r ′ is formed as a vertical plane corresponding to the rear face of the attachment plate Tr of the subassembly comprising the blade bracket and so on (see FIG. 6 ). Here, when the connecting member 8 r ′ is joined to the center frame 7 ′ such that the central welding portion 8 r 2 ′ of the connecting member 8 r ′ is welded to the right side plate 7 sr ′ of the center frame 7 ′, the joining face 8 rm ′ of the connecting member 8 r ′ is adjacent to the front face 7 m ′ of the center frame 7 ′ as shown in FIG. 6 , and thus forms a single plane together with the front face 7 m ′ of the center frame 7 ′. The joining face 8 lm ′, which serves as a joining portion for the rear face of the attachment plate Tl of the subassembly comprising the blade bracket and so on, is formed on a part of the front face of the connecting member 8 l ′ as a vertical plane corresponding to this rear face. Here, when the connecting member 8 l ′ is joined to the center frame 7 ′ such that the central welding portion 812 ′ of the connecting member 8 l ′ is welded to the left side plate 7 s 1 ′ of the center frame 7 ′, the joining face 8 lm ′ of the connecting member 8 l ′ is adjacent to the front face 7 m ′ of the center frame 7 ′, and thus forms a single plane together with the front face 7 m ′ of the center frame 7 ′. Note that as long as the joining faces 8 rm ′, 8 lm ′ of the connecting members 8 r ′, 8 l ′, which serve as faces to which the blade bracket 2 Br is joined, form a plane which matches the rear faces of the attachment plates Tr, Tl of the subassembly comprising the blade bracket and so on, these faces are not strictly limited to a vertical plane. Next, a method of joining the blade bracket 2 Br to the center frame 7 ′ and connecting members 8 r ′, 8 l ′ will be described. The rear faces of the attachment plates Tr, Tl of the subassembly comprising the blade bracket 2 Br and so on are aligned with and caused to contact the front face 7 m ′ of the center frame 7 ′ and the joining face 8 rm ′ of the connecting member 8 r ′, and the front face 7 m ′ of the center frame 7 ′ and the joining face 8 lm ′ of the connecting member 8 l ′, which respectively form single planes, and thus disposed in a predetermined position. Next, the rear face of the attachment plate Tr in the subassembly comprising the blade bracket 2 Br and so on is welded to the front face 7 m ′ of the center frame 7 ′ and the joining face 8 rm ′ of the connecting member 8 r ′, and the rear face of the attachment plate Tl in the subassembly comprising the blade bracket 2 Br and so on is welded to the front face 7 m ′ of the center frame 7 ′ and the joining face 8 lm ′ of the connecting member 8 l′. Simultaneously, the rear face 2 Br 42 of the reinforcing plate 2 Br 4 and the rear faces 2 Br 11 of the cylinder fulcrum plates 2 Br 1 in the subassembly comprising the blade bracket 2 Br and so on are welded to the front face 7 m ′ of the center frame 7 ′. According to this constitution, the right blade fulcrum plates 2 Br 2 on the blade bracket 2 Br are welded to the attachment plate Tr, the left blade fulcrum plates 2 Br 3 are welded to the attachment plate Tl, and thus a subassembly comprising the blade bracket 2 Br and the attachment plates Tr, Tl is manufactured. By welding the attachment plate Tr of the subassembly to the center frame 7 ′ and connecting member 8 r ′, and welding the attachment plate Tl to the center frame 7 ′ and connecting member 8 l ′, the blade bracket 2 Br is joined to the center frame 7 ′ and connecting members 8 r ′, 8 l ′ via the attachment plates Tr, Tl. Hence the attachment plate Tr is interposed between the welding location of the center frame 7 ′ and connecting member 8 r ′ and the right blade fulcrum plates 2 Br 2 of the blade bracket 2 Br, and thus the welding location between the center frame 7 ′ and connecting member 8 r ′ and the welding locations of the right blade fulcrum plates 2 Br 2 are prevented from overlapping directly. Similarly, the attachment plate Tl is interposed between the welding location of the center frame 7 ′ and connecting member 8 l ′ and the left blade fulcrum plates 2 Br 3 of the blade bracket 2 Br, and thus the welding location between the center frame 7 ′ and connecting member 8 l ′ and the welding locations of the right blade fulcrum plates 2 Br 3 are prevented from overlapping directly. Thus when the blade bracket 2 Br is welded to the center frame 7 ′ and connecting members 8 r ′, 8 l ′, overlapping welding between the right blade fulcrum plates 2 Br 2 on the blade bracket 2 Br and the welding location of the center frame 7 ′ and connecting member 8 r ′can be prevented, and overlapping welding between the left blade fulcrum plates 2 Br 3 and the welding location of the center frame 7 ′ and connecting member 8 l ′can also be prevented. Further, the right blade fulcrum plates 2 Br 2 of the blade bracket 2 Br are welded to the plate-form attachment plate Tr, and hence straight line welding is possible. Likewise, the left blade fulcrum plates 2 Br 3 of the blade bracket 2 Br are welded to the plate-form attachment plate Tl, and hence straight line welding is possible. Straight line welding may also be employed to join the attachment plates Tr, Tl to the center frame 7 ′ and connecting members 8 r ′, 8 l ′ respectively. Hence the weldability of the blade fulcrum plates 2 Br 2 , 2 Br 3 on the blade bracket 2 Br is improved, and the weldability and joining strength of the attachment plates Tr, Tl are increased, leading to an improvement in mechanical reliability. Furthermore, the blade bracket 2 Br is connected to the center frame 7 ′ and connecting members 8 r , 8 l ′ via the attachment plates Tr, Tl, and hence operating load stress transmitted to the blade bracket 2 Br from the blade B' is dispersed upon transmission to the attachment plates Tr, Tl, enabling smooth transmission thereof to the vehicle body. As a result, the load-withstanding strength in relation to operating loads from the blade B' is heightened, leading to an improvement in reliability, the prevention of wear to the vehicle body, and extended longevity. In addition, as shown in FIG. 6A , the front face 7 m ′ of the center frame 7 ′ and the joining faces 8 rm ′, 8 lm ′ of the connecting members 8 r , 8 l ′ form a single plane, and hence loads caused by the traveling of the crawler belt r′ i , which are transmitted from the connecting members 8 r , 8 l ′ to the center frame 7 ′, are transmitted from the front face plate of the connecting members 8 r , 8 l ′, disposed in a position along the load transmission direction, to the front side plate 7 sm ′ of the center frame 7 ′. Thus running loads from the connecting members 8 r , 8 l ′ are transmitted smoothly to the center frame 7 ′. As a result, the load-withstanding strength in relation to operating loads is heightened, leading to an improvement in mechanical reliability. Further, since the attachment plates Tr, Tl are constituted by plate-form steel plates, manufacture is easy and costs are low. Similarly to the first embodiment, a wide blade bracket 2 Br can be used, and hence the length of the moment lever of an operating load from the blade B' increases, causing the load generated by the moment of the operating load to decrease, and the moment load acting on the cylinder fulcrum plates 2 Br 1 , right blade fulcrum plates 2 Br 2 , and left blade fulcrum plates 2 Br 3 to decrease. Hence an operating load generated by the blade B' that is transmitted to the vehicle body via the blade bracket 2 Br decreases, which is effective in preventing wear to the vehicle body and improving the operating performance of the blade B'. Note that in the embodiment described above, an example was described in which attachment members for attaching the blade bracket 2 Br to the center frame 7 ′ and connecting members 8 r ′, 8 l ′ are constituted by the plate-form attachment plates Tr, Tl, but the attachment members do not necessarily have to be plate-form. For example, the joining faces of the connecting members may be disposed behind the front face of the center frame and provided with a stepped portion such that the attachment members comprise a face which runs along the stepped portion between the front face of the center frame and the joining faces of the connecting members, and a face to which the joining portion of the blade bracket 2 Br is welded. Likewise in this constitution, the attachment members are interposed between the blade bracket 2 Br and the center frame and connecting members, and hence the blade bracket 2 Br is welded to the center frame and connecting members via the attachment members. As a result, the welding location of the blade bracket 2 Br does not overlap the welding location between the center frame and connecting members. Further, the joining portion of the blade bracket 2 Br is welded to the face of the attachment members, enabling straight line welding and thus improving weldability. As a result, the joining strength of the blade bracket 2 Br to the center frame and connecting members is increased, leading to an improvement in mechanical reliability. Moreover, operating load stress transmitted to the blade bracket 2 Br from the blade B' is dispersed upon transmission to the attachment members, enabling smooth transmission thereof to the vehicle body via the attachment members. As a result, the mechanical reliability is improved. Thus similar effects to those of the embodiment described above are achieved. In addition, one face of the attachment members is a plane to which the joining portion of the blade bracket 2 Br is welded, and the other face of the attachment members is a face to which the center frame and connecting members are welded, and hence the attachment members are also applicable to a case in which the joining portion of the center frame and the joining portions of the connecting members are formed with an arbitrary stepped portion, thus enabling greater design freedom. Note that in the embodiment described above, a case was described in which the blade bracket 2 Br is joined to the center frame 7 ′ and connecting members 8 r ′, 8 l ′ by being welded via attachment members such as the attachment plates Tr, Tl, but joining may be performed using bolts instead of welding. Next, modified examples of the first and second embodiments will be described using FIGS. 7 , 8 . FIG. 7 shows top views of various modified examples of the first embodiment in which blade brackets 3 Br, 4 Br, 5 Br are joined respectively to the front face 7 m ′ of the center frame 7 ′ and the joining faces 8 rm ′, 8 r 1 ′ of the connecting members se, 8 l ′ without the interposition of attachment members. FIG. 7A shows a first modified example in which the joining faces 8 rm ′, 8 lm ′ serving as the joining portions of the connecting members 8 e , 8 l ′ with the blade bracket 3 Br are positioned rearward of the front face 7 m ′ of the center frame 7 ′. In this case, cylinder fulcrum plates 3 Br 1 , right blade fulcrum plates 3 Br 2 , left blade fulcrum plates 3 Br 3 , and a reinforcing plate 3 Br 4 of the blade bracket 3 Br are formed in alignment with the stepped portion between the front face 7 m ′ of the center frame 7 ′ and the joining face 8 rm ′ of the connecting member 8 r ′, and the stepped portion between the front face 7 m ′ of the center frame 7 ′ and the joining face 8 lm ′ of the connecting member 8 l′. FIG. 7B shows a second modified example in which the joining faces 8 rm ′, 8 lm ′ serving as the joining portions of the connecting members 8 r ′, 8 l ′ with the blade bracket 4 Br are positioned forward of the front face 7 m ′ of the center frame 7 ′. In this case, cylinder fulcrum plates 4 Br 1 , right blade fulcrum plates 4 Br 2 , left blade fulcrum plates 4 Br 3 , and a reinforcing plate 4 Br 4 of the blade bracket 4 Br are formed in alignment with the stepped portion between the front face 7 m ′ of the center frame 7 ′ and the joining face 8 rm ′ of the connecting member se, and the stepped portion between the front face 7 m ′ of the center frame 7 ′ and the joining face 8 lm ′ of the connecting member 8 l′. FIG. 7C shows a third modified example in which front faces 8 rz ′, 8 lz ′ comprising the joining faces 8 rm ′, 8 lm ′ of the connecting members 8 r , 8 l ′ form continuous curved surfaces with the front face 7 m ′ of the center frame 7 ′. In this case, cylinder fulcrum plates 5 Br 1 , right blade fulcrum plates 5 Br 2 , left blade fulcrum plates 5 Br 3 , and a reinforcing plate 5 Br 4 of the blade bracket 5 Br are formed in alignment with the front face 7 m ′ of the center frame 7 ′, the joining face 8 rm ′ of the connecting member 8 r ′, and the joining face 8 lm ′ of the connecting member 8 l′. FIG. 8 shows top views of various modified examples of the second embodiment in which blade brackets 6 Br, 7 Br, 8 Br are joined respectively to the front face 7 m ′ of the center frame 7 ′ and the joining faces 8 rm ′, 8 r 1 ′ of the connecting members 8 r , 8 l ′ via attachment plates Tra, Tla, attachment plates Trb, Tlb, and attachment plates Trc, Tlc respectively. FIG. 8A shows a fourth modified example in which a rear face 6 Bru of the blade bracket 6 Br is formed as a single plane, and this blade bracket 6 Br is welded via the plate-form attachment plates Tra, Tla to the front face 7 m ′ of the center frame 7 ′, the joining face 8 rm ′ of the connecting member 8 r ′, and the joining face 8 lm ′ of the connecting member 8 l ′ in which recessed portions corresponding to the attachment plates Tra, Tla are formed. In this constitution, the rear face 6 Bru of the blade bracket 6 Br is formed as a single plane, thereby simplifying the constitution and manufacture of the blade bracket 6 Br. As a result, the blade bracket 6 Br is suited for use as a standardized component for application to various types of construction machine. FIG. 8B shows a fifth modified example in which the front face 8 rz ′ of the connecting member 8 r ′ is formed as a continuous curved surface with the front face 7 m ′ of the center frame 7 ′ and joined thereto, the front face 8 lz ′ of the connecting member 8 l ′ is formed as a continuous curved surface with the front face 7 m ′ of the center frame 7 ′ and joined thereto, and thus the blade bracket 7 Br is welded to the front face 7 m ′ of the center frame 7 ′, and the joining faces 8 rm ′, 8 lm ′ on the front faces 8 rz ′, 8 lz ′ of the connecting members 8 r , 8 l ′ via the plate-form attachment plates Trb, Tlb. In this case, the respective rear faces of cylinder fulcrum plates 7 Br 1 , right blade fulcrum plates 7 Br 2 , left blade fulcrum plates 7 Br 3 , and a reinforcing plate 7 Br 4 of the blade bracket 7 Br take a form which corresponds with the front face 7 m ′ of the center frame 7 ′, the joining face 8 rm ′ of the connecting member 8 r ′, and the joining face 8 lm ′ of the connecting member 8 l ′, and are formed with recessed portions corresponding to the attachment plates Trb, Tlb. FIG. 8C shows a sixth modified example in which the front face 8 rz ′ of the connecting member 8 r ′ is formed as a plane having an incline in relation to the front face 7 m ′ of the center frame 7 ′ and thus joined thereto, and the front face 8 lz ′ of the connecting member 8 l ′ is formed as a plane having an incline in relation to the front face 7 m ′ of the center frame 7 ′ and thus joined thereto. In this state, the blade bracket 8 Br is welded to the front face 7 m ′ of the center frame 7 ′, the joining face 8 rm ′ on the front face 8 rz ′ of the connecting member 8 r ′, and the joining face 8 lm ′ on the front face 812 of the connecting member 8 l ′ via the plate-form attachment plates Trc, Tlc. In this case, the respective rear faces of cylinder fulcrum plates 8 Br 1 , right blade fulcrum plates 8 Br 2 , left blade fulcrum plates 8 Br 3 , and a reinforcing plate 8 Br 4 of the blade bracket 8 Br take a form which corresponds with the front face 7 m ′ of the center frame 7 ′, the joining face 8 rm ′ of the connecting member 8 r ′, and the joining face 8 lm ′ of the connecting member 8 l ′, and are formed with recessed portions corresponding to the attachment plates Trc, Tlc. Note that in the modified examples shown in FIGS. 7 , 8 , examples were described in which the front face 7 m ′ of the center frame 7 ′ and the joining faces 8 rm ′, 8 lm ′ of the connecting members 8 r ′, 8 l ′ are vertical faces, but these faces may be faces other than vertical faces such as inclined faces which are inclined in relation to the vertical direction, and hence are not strictly limited to vertical faces. Further, bolts may be used to join the blade bracket to the front face 7 m ′ of the center frame T and the joining faces 8 rm ′, 8 lm ′ of the connecting members 8 r , 8 l′. Note that in the embodiments described above, an example was described in which a hydraulic shovel is used as the construction machine, but the construction machine according to the present invention may of course be applied effectively to a machine other than a hydraulic shovel having a similar constitution. For example, the present invention may be applied effectively to a machine other than a hydraulic shovel which has a base carrier constitution, such as a crawler dump, a bulldozer, or an agricultural machine.

An object of the present invention is to provide a construction machine which precipitates the removal of earth that is churned up onto a vehicle body from the vehicle body, which reduces transfer loads on a blade bracket, which improves the attachability of the blade bracket, and which achieves standardization of the blade bracket. The construction machine according to the present invention is constituted such that a frame of a crawler belt-type traveling body comprises a center frame, a pair of truck frames disposed on the outside of two side portions of the center frame, a connecting member which connects the center frame to the truck frames, and a blade bracket which is joined to the center frame and the connecting member.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION [0001] The invention relates to geared motors for window regulators in vehicles and more particularly window regulators with a window braking and irreversibility device. [0002] The known window regulators have means for driving a window up and down. Persons may try to open a vehicle window by applying a downward pressure to the closed or partly opened window, in order to illegally gain access to the passenger compartment of the vehicle. [0003] A window regulator, sold by the assignee under reference number 101087, comprises an electric motor with a reduction gear; an output shaft of the motor has teeth at one end forming a worm. This worm engages with a wheel to form a wheel and worm reduction gear. The wheel transmits the movement to a cable driving drum. The cable drives a slider attached to the window up and down. In this window regulator, a wheel and worm reduction gear with transmission efficiency of the order of 40 percent is used. When pressure is applied to the window, the motor and the low efficiency transmission lock the rotation of the wheel. The irreversible driving up and down of the window by the drum is thus assured. [0004] This device has disadvantages. Because of the low transmission efficiency, driving the drum requires the use of a motor that is oversized relative to the drive force actually applied to the drum. The motor is thus bulky and costly. [0005] German Patent Application DE-A-3110368 discloses a window regulator comprising a drive component coupled to a drum. The drum drives a window up and down by means of a cable attached to a window slider. The drum is equipped with a mechanical locking device. A gear placed on the axis of the drive shaft is equipped with lugs projecting axially. These lugs lock against a fixed plate arranged in the structure of the window regulator. The window regulator is released when the drive shaft drives the drum and locked when the drum drives the drive shaft. [0006] This device is complex and costly. Moreover, the drum is bulky. This device also requires the use of an additional braking system in order to stop the window from rising when an obstruction is detected. [0007] The device sold by the assignee under reference number 101087 also comprises an anti-pinch system. The system measures the current consumed and the rotating speed of the motor. The system detects the pinching of an object between the top of the window and the window frame from variations in these parameters. The power supply to the motor is then interrupted and the driving of the window is thus stopped. [0008] This anti-pinch device has disadvantages. The response time between the pinching of an object and the actual stopping of the movement of the window is significant. As the window is still being driven during this response time, a user may be injured. It is also more difficult to obtain approval for vehicles using this type of window regulator. SUMMARY OF THE INVENTION [0009] There is therefore a need for a window regulator and a geared motor that provide a solution to one or more of these disadvantages. The object of the invention is thus a window regulator comprising an electric motor having a drive shaft, a window slider, a transmission having an input driven by the drive shaft and an output driving the slider, with a piezoelectric element selectively locking the position of the slider. [0010] According to one embodiment, the piezoelectric element acts upon the drive shaft. [0011] According to another embodiment, the piezoelectric element has a friction surface that is able to lock the position of the slider. [0012] According to a further embodiment, the friction surface has a coefficient of friction on the shaft greater than 0.15. [0013] According to yet another embodiment, the transmission has a reduction gear with a speed reduction ratio between the input and the output of the geared motor of less than 1. [0014] Provision may also be made for the reduction gear to comprise a worm wheel system, the worm being provided on the drive shaft. [0015] According to one embodiment, the piezoelectric element forms a journal of the drive shaft. [0016] According to another embodiment, the piezoelectric element locks the drive shaft by means of a split bearing. [0017] According to a further embodiment, the motor comprises a housing with a journal, and the piezoelectric element has an outer surface permanently housed in the journal and an inner surface acting upon the bearing. [0018] According to yet another embodiment, the piezoelectric element is piezostrictive. [0019] Provision may also be made for the piezoelectric element to selectively brake the movement of the slider. [0020] Another object of the invention is a geared motor comprising a drive shaft, a reduction gear coupled to the drive shaft with a speed reduction ratio between the input and the output greater than 1, and a piezoelectric element selectively locking the drive shaft. [0021] According to one embodiment, the piezoelectric element has a friction surface which is able to lock the shaft, this surface preferably having a coefficient of friction with the shaft greater than 0.15. [0022] According to another embodiment, the reduction gear has a worm wheel system, the worm being provided on the drive shaft. [0023] According to a further embodiment, the piezoelectric element forms a journal of the drive shaft. [0024] According to yet another embodiment, the piezoelectric element locks the drive shaft by means of a split bearing. [0025] Provision may also be made for the geared motor to comprise a housing with a journal, the piezoelectric element having an outer surface permanently housed in the journal and an inner surface acting upon the bearing. [0026] According to one embodiment, the piezoelectric element is piezostrictive. [0027] According to another embodiment, the piezoelectric element selectively brakes the drive shaft. [0028] A further object of the invention is a method for operating a window regulator comprising the steps of locking the slider position by means of the piezoelectric element when the motor is switched off and unlocking the slider position when the motor is supplied with power. [0029] According to one embodiment, the piezoelectric element has two terminals, is piezostrictive and is not supplied with power during the slider locking step. [0030] According to another embodiment, the method comprises the steps of the driving of the slider by the motor, obstruction detection and braking of the movement of the slider by means of the piezoelectric element. [0031] According to a further embodiment, the method also comprises a stage of short-circuiting the power supply to the motor after an obstruction has been detected. [0032] Other characteristics and advantages of the invention are given in the following description of embodiments of the invention, given by way of example and with reference to the appended drawings. BRIEF DESCRIPTION OF THE DRAWINGS [0033] FIG. 1 is if a schematic representation of a window regulator comprising a geared motor according to the invention; [0034] FIG. 2 is a longitudinal cross-section view of a geared motor according to the invention; [0035] FIG. 3 is a transverse cross-section view of details in FIG. 2 . DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS [0036] The invention provides in particular a window regulator and a geared motor driving a window slider. A piezoelectric element locking the slider locks the position of the slider when the motor is switched off. Thus when an attempt is made to open the window by forcing it from the outside, the window stays locked in its position. [0037] FIG. 1 shows a schematic view of a window regulator 1 according to an embodiment of the invention. The window regulator 1 comprises a slider 2 attached to a window, not shown. The slider 2 can slide for example on a guide rail 3 . A cable 4 drives the slider 2 . This cable 4 is itself driven by a drum 5 . This drum 5 is coupled to the wheel of a geared motor 6 , for example by means of a damper. The geared motor is for example fixed to a structural part 7 of the window regulator 1 . [0038] As shown in more detail in FIG. 2 , the geared motor 6 is housed in a housing 67 . A motor 64 has a rotor 65 and a power supply and control device 66 that can be produced in a way known per se. The wheel 61 is the output element of a wheel and worm reduction gear. The wheel 61 is driven by a worm gear pair 62 made on the output shaft 63 of the motor 64 . The reduction gear ensures the transmission of mechanical power between the drive shaft 63 and the drum 5 . The reduction gear also has a speed reduction ratio between the input and the output of the geared motor greater than 1. The input speed of the reduction gear is thus greater than the output speed of the reduction gear. Although a wheel and worm reduction gear was used in the example, it is possible to use any type of appropriate reduction gear. A damper 73 connects the drum 5 and the wheel 61 . The damper in particular absorbs the shocks during the transient drive phases of the motor. The drum 5 serves as winding component for the cable 4 that drives the slider. [0039] In this embodiment, the geared motor comprises a piezoelectric element that selectively locks the position of the slider. The use of a piezoelectric element for locking the slider permits the use of a small size locking part with a simple shape. An appropriate piezoelement is moreover easy to produce. The locking of the slider can also be selectively controlled using simple means with a piezoelectric element. The piezoelectric element can lock the slider position by braking. Braking that locks the position of the slider to a force of 500 N applied to the window is seen as locking. The slider position is selectively locked in order to ensure the irreversibility of the window regulator. Thus, the driving of the slider by the window is prevented, while the driving of the slider by the motor is permitted. Means allowing for the selective locking of the slider will be detailed later. Generally, the slider position is locked when the motor is switched off and the slider position is unlocked when the motor is supplied with power. As the irreversibility is selective, it is possible to use a reduction gear with high transmission efficiency. A less powerful motor can then be used, for example a 20-Watt motor. [0040] The slider position is locked in the example in FIG. 2 by locking the drive shaft by means of the piezoelectric element. As shown in more detail in FIG. 3 , the piezoelectric element can be used as a journal of the motor. The geared motor can thus be kept small. Moreover, the volume of the drum is not increased. A substantially cylindrical piezoelectric element can be used. The piezoelectric element can be placed in a recess in the housing 67 or be mounted with a tight fit in a hole in the housing 67 . Generally, an outer surface of the piezoelectric element can be permanently housed in a hole in the housing. It is advantageous to arrange the piezoelectric element in the housing 67 of the geared motor 6 . The electrical connections of the piezoelectric element can thus be located in the same place as the motor power supply electrical connections. The electrical wiring of the window regulator 1 can thus be simplified. [0041] The piezoelectric element 68 can lock the drive shaft 63 by means of a shaft rotation guide component. A split bearing 69 can for example be used for this, as shown in FIGS. 2 and 3 . In this embodiment, the split bearing 69 is housed against an inner surface of the piezoelectric element 68 . The bearing has a substantially longitudinal split 70 . The diameter of the bearing 69 can thus vary. By placing a radial load on the bearing 69 , the width of the slit 70 and the diameter of the bearing can be reduced. The brake force applied by the bearing 69 on the shaft 63 is thus increased. When the piezoelectric element 68 is in a dilated position, i.e. when its inner diameter has a minimum size, the inner surface of the piezoelectric element 68 acts upon the split bearing 69 and reduces the width of the split 70 . The rotation of the drive shaft 63 is then locked by the bearing 69 . [0042] A piezoelectric element 68 made of quartz or barium titanate can be used. A piezostrictive material is preferably used to make the piezoelectric element. Thus, the piezoelectric element is in a dilated position or locking position when idle. When the power supply to the piezoelectric element is interrupted, due to a dead battery for example, the piezoelectric element 68 still continues to lock the slider position. A 10 mm×8 mm×5 mm piezoelectric element can be used with a reduction gear with a speed reduction ratio of 73 to ensure a locking force of 500 N on the slider. An unlocking voltage of 12 to 60 V between the electrodes releases the drive shaft. [0043] An electrode is preferably arranged on the outer circumference of the piezoelectric element and another electrode on the inner circumference of the piezoelectric element. A greater variation of the inner diameter of the piezoelectric element is thus ensured. [0044] A split bearing 69 made of sintered and lubricated bronze can be used. A bearing with dimensions of inner diameter 8 , a minimum thickness of 5 mm and a minimum outer diameter of 10 mm is suitable to ensure the locking of the drive shaft 63 . [0045] Provision can also be made for the piezoelectric element 68 to act directly upon the drive shaft 63 . A piezoelectric element 68 with a friction surface with a high coefficient of friction with the drive shaft will preferably be used. A coating with a high coefficient of friction with the drive shaft can also be used. This coating can for example be applied to the surface of the piezoelectric element coming into contact with the drive shaft. A friction surface with a coefficient of friction greater than 0.15 is preferably used. [0046] The arrangement of the piezoelectric element 68 upstream of the reduction gear, and on the drive shaft in particular, is advantageous. A piezoelectric element with reduced braking power can be used because the reduction gear multiplies the braking torque applied by the piezoelectric element on the slider. [0047] The piezoelectric element 68 can also be used to selectively brake the movement of the slider 2 . The arrangement of the piezoelectric element on the drive shaft is also advantageous for carrying out this braking. It is possible to brake the movement of the slider when an obstruction of the window is detected. The braking using the piezoelectric element allows for the inertia of the motor to be reduced more quickly. The response time between the identification of an obstruction and the stopping of the slider and the window can thus be reduced. Moreover, a piezoelectric element that already exists to ensure that the movement of the slider is irreversible is used for this. [0048] A piezoelectric element control shared with the control of the motor power supply can be used. Provision can be made for the control to apply different voltages to the terminals of the piezoelectric element depending on the operation to be carried out. Different braking or unlocking voltages can be used depending on the external conditions detected, such as the temperature, the power supply status of the motor or the pinching of an object. [0049] The invention also relates to methods for operating the window regulator and the geared motor described. [0050] According to a first method of operation, the slider position is locked by means of the piezoelectric element when the motor is switched off. The piezoelectric element can for example be kept idle during this step, for example when a piezostrictive piezoelectric element is used. The position of the slider is unlocked, for example by exciting a piezostrictive piezoelectric element, when the motor is supplied with power. [0051] According to a second method for operating a window regulator, the steps of driving the slider by the motor are carried out. An obstruction of the window is detected by appropriate means. A braking order is then sent to the piezoelectric element for example when an obstruction is detected. The movement of the slider is then braked by means of the piezoelectric element. [0052] According to one embodiment, the power supply to the motor is short-circuited after the detection of an obstruction. Additional braking is thus provided by a motor brake. [0053] Of course this invention is not limited to the examples and embodiments described and shown, but is open to a number of embodiments accessible to a person skilled in the art. Although the locking of the slider position on a drive shaft has mainly been described, provision can of course be made to carry out this locking in any suitable place. For example, provision can be made to install a piezoelectric locking element placed on a slider and acting on a guide rail. Provision can also be made for a piezoelectric element on the reduction gear wheel acting upon the housing of a geared motor.

A window regulator includes an electric motor having a drive shaft, a window slider, a transmission having an input driven by a drive shaft, and an output driving the slider. A geared motor includes a drive shaft, a reduction gear coupled to the drive shaft and having a transmission ratio less than 1, and a piezoelectric element selectively locking the drive shaft. The window regulator can be used to prevent fraudulent opening of a window and to reduce the jamming force of an object between the window and the window frame.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the door lock art and more particularly to an improved security door lock providing signal information indicating the unauthorized opening of a door. 2. Description of the Prior Art Security devices are often utilized in various door lock arrangements to protect the privacy and/or contents of businesses, homes apartments and other places. Such security devices as incorporated in doors have often been intended to prevent the unauthorized entry into the premises protected by the security device since conventional door locks including handle operated latching structures and deadbolts can usually be forced or otherwise rendered inoperable. That is, conventional handle operated latches can often be forced open by the insertion of a rigid prying tool or even a stiff plastic such as a credit card between the door and the jamb to force the latch into a retracted position. Even deadbolts can be cut by the insertion of a sawing instrument between the door and the jamb and cutting, through the deadbolt. Further, many alarm devices incorporated into the conventional door lock structures have often been comparatively complicated and/or expensive structures not adapted to the requirements for mass production and installation. In U.S. Pat. No. 3,402,405 there is shown a self locking burglar alarm system which uses a spring biased bolt arm extending across and through opposite walls of a housing. An audible alarm and switching means are also located in the housing. One end of the bolt arm engages a latch plate near an opening while the other end is used to move the arm back to extend the spring to cock the arm. When the window or door upon which the alarm is mounted is moved, the end of the arm moves from the latch plate into the opening to provide a lock. At the same time the arm actuates the the switching means to trigger the alarm. The device as so disclosed has several disadvantages. First of all, the structure does not lend itself to mass manufacturing and installation techniques to produce a heavy duty lock. Also, since the end of the arm opposite the one engaging the latch plate extends out of the housing, it can be reached through an adjacent window to disable the alarm. Further, the cooperative relationship between the operative end of the bolt arm and the latch plate are such that it is possible for an intruder to move the bolt arm to an inoperative position from outside the area to be protected. Many other mechanical and/or electromechanical security devices have been proposed for incorporation into security devices for various purposes. However, a security device operated by magnetic forces has not heretofore been available for inclusion in mass production and installation techniques. In U.S. Pat. No. 2,193,488 there is shown a refrigerator lock mechanism with a switch to activate the light within the refrigerator. No magnetically operated structure is provided. In U.S. Pat. No. 3,770,930 there is shown a safety switch for a microwave oven which employs an irregular shaped actuator that only allows power to turn on when the microwave door is closed and the actuator is meshed. In U.S. Pat. No. 3,851,325 there is shown a lock and alarm structure utilizing a spring and a bolt. An alarm 66 is also provided with batteries in the lock housing. In the armed position, if the door is moved, the bolt slips from a shoulder and the spring pushes the bolt forward to activate the alarm. In U.S. Pat. No. 4,248,463 there is shown a security system with a dead bolt lock and sensing and control means for sensing whether or not the lock is in the locked position. Means are also provided to activate and deactivate the alarm and also to utilize an information signal generated by the structure to operate an electric appliance. In U.S. Pat. No. 5,257,841 there is disclosed an electrical lock strike device to monitor whether a deadbolt is present or not. In none of the prior art patents is there even shown or suggested the use of a magnet with the attendant use of magnetic forces to provide the actuation of an alarm system. Thus, there has long been a need for a magnetically operated security lock which can be conveniently incorporated into existing lock structures for mass production and installation without requiring major rework or rededsign of the basic lock structure. BRIEF DESCRIPTION OF THE INVENTION Accordingly, it is an object of the present invention to provide a security lock operated by magnetic forces. It is another object of the present invention to provide a magnetically actuated alarm arrangement which may be incorporated into locks for doors and other locking structures, It is yet another object of the present invention to provide a magnetically operated security lock which may be incorporated into present lock structure with a minimum of redesign and/or rework for mass manufacturing and installation thereof. The above, and other objects of the present invention are achieved, in a preferred embodiment thereof, in a door lock arrangement. While the present invention is described as incorporated into a door lock, it will be appreciated that the invention may be incorporated into many different structures to provide a security arrangement. The door utilized in describing the present invention is of the type hung in a door jamb. In many structures such as residential housing, the door jamb is mounted on a frame of doubled 2 by 4's. However, for convenience, the jamb and doubled 2 by 4's to which the jamb is attached are collectively referred to as the jamb even though part of the invention may be in the 2 by 4's. The preferred embodiment of the present invention incorporates a magnet in the latch member of the latching means. The latching means may be a handle operated latch on the door which is spring loaded to enter into a cavity of the jamb, may be a manually operated deadbolt, or other latching means. A reed switch is incorporated into the jamb and communicates with the cavity accepting the latch member. The reed switch may be a normally open or a normally closed reed switch. When the door is in the closed position the latch member carrying the magnet enters into a latch receiving cavity in the jamb and is in switch operating relationship to the switch in the jamb. Upon being subjected to a change in the magnetic flux of the magnetic forces from the magnet, the switch changes its condition and generates an information signal to indicate that the magnet has moved away from the switch operating relationship to the switch which condition occurs preparatory to the door being opened. The information signal indicates that an attempt is being made to open the door and it may be connected to conventional alarm means such as a siren, bell, or the like and/or into a status panel to indicate that the attempt to open the door has been made. A conventional disabling means may be incorporated into the circuitry to prevent the information signal from being generated in the event that the attempt to open the door is authorized. Such disabling means and devices using the information signal thus generated are not, per se, part of the present invention. Further, the latching means for operating the latch member carrying the magnet are not, per se, a part of the present invention. In those embodiments of the present invention where a status board is utilized to monitor the status of a plurality of doors, such as in an apartment complex, the information signal may be used to provide a light and is generated when the door is closed and the magnet is in switch operating relationship to the switch. In such an embodiment, the light on the status board for each door indicates that the door is closed and the if the magnet is moved out of the switch operating relationship to the swich the information signal is terminated and the light goes out which indicates an attempt is being made to open the door. Alternatively, there may be no signal generated when the latch is in switch operating relationship to the switch and no light is on the status board, thus indicating that the door is closed and the information signal is generated when the magnet moves out of the switch operating relationship to the switch and the light goes on at the status board. Thus, in those embodiments of the present invention used with a status board, the "information signal" may be either the generation of the actuating signal for lighting the status light or the termination of the actuating signal to extinguish the light. In those embodiments of the present invention used with other alarms such as a siren or the like, the "information signal" is the signal that actuates the alarm for the condition of the magnet moved away from the switch operating relationship to the switch. In some embodiments of the present invention, the magnet is an elongated cylinder which bridges the space between the door and the jamb when the door is in the closed position and the latch member protrudes into the jamb. The magnet is rotatably mounted in the magnet receiving cavity in the latch member by having the magnet receiving cavity with a slightly larger diameter than the magnet so that the magnet may rotate. If an attempt to cut the latch member is made, the rotation of the magnet prevents the sawing instrument from cutting into through the latch member. In another embodiment of the present invention, the magnet may be provided by a magnetic coating of magnetic material on the outer face of the latch member. In another embodiment of the present invention, the magnet may be a thin disc magnet. In yet another embodiment of the present invention, the entire latch member, whether a deadbolt, lock bar, tapered spring loaded latch or otherwise, may be a magnet. In each of the above described preferred embodiments of the present invention only a minimal amount of redesign and/or modification to existing structures is required to incorporate the invention into presently available lock hardware. BRIEF DESCRIPTION OF THE DRAWINGS The above and other embodiments of the present invention maybe more fully understood from the following detailed description taken together with the accompanying drawing in which similar reference characters refer to similar elements throughout and in which: FIG. 1 is a perspective view of a preferred embodiment of the present invention with the door in the open position and as incorporated in a deadbolt; FIG. 2 is a front view partially broken away of a first illustrative embodiment shown in FIG. 1 with the door in the closed position FIG. 3 is a cross-sectional view of a second illustrative embodiment consistent with the present invention. FIG. 4 is a plan view of the second illustrative embodiment of FIG. 4. FIG. 5 is a third illustrative embodiment consistent with the present invention showing a deadbolt; FIG. 6 illustrates a fourth illustrative embodiment consistent with the present invention as incorporated in a handle operated latching means; and FIG. 7 illustrates another embodiment of the present invention as utilized in a vertical lock bar application. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing, there is shown in FIG. 1 a perspective view of an embodiment, generally designated 10, consistent with the present invention. As shown on FIG. 1 there is a door 12 having a deadbolt means generally designated 14 mounted to the door 12 by a mounting plate 21 therein by, for example, screw means 16. An outer door jamb 19 which is associated with the door 12 is also shown on FIG. 1 and the door is in the open position thereof as illustrated in FIG. 1. For illustration purposes, the deadbolt means 14 is shown in its extended, locked position, although the deadbolt means 14 would be retracted, closed when door 12 is opened, or closed in relation to moving contact with door jamb 18. In many structures the outer door jamb 19 is coupled to doubled 2 in by 4 in studs indicated at 20 as part of the door framing means. For convenience of describing the present invention, the outer door jamb 19 and doubled 2 by 4's 20, or any other structure upon which the outer door jamb 19 may be mounted, are collectively referred to herein as the door jamb 18. The door jamb 18 has a latch member receiving cavity 24, which has defining first walls 22, and a switch means receiving cavity. 28, which has defining second walls 26. The switch means receiving cavity 28 opens into and is adjacent to the latch member receiving cavity 24. A magnetically operated switch means 30 is positioned in the switch means receiving cavity 28. The switch means 30 may be a reed switch of the normally open type or of the normally closed type, or may be of the type having both a normally open switch and a normally closed switch in a single switch casing to allow generation of two information signals upon actuation. The switch means 30 may, for example, be a reed switch such as the switch sold by Nutone, Cincinnati, Ohio under model number 4-Q-87. The door 12 is movable in the directions indicated by the double ended arrow 32 from the open position shown in FIG. 1 to a closed position as shown in FIG. 3. The latching means 14 of the present invention has a latch member 34 which, in the first embodiment 10, is shown as a deadbolt, but may be any other latch member providing the function thereof. The latch member 34 has a magnet means 36 positioned in a magnet receiving cavity 38 defined by first walls 39. A retention plate 40 is coupled to the forward face 42 of the latch member 34 by, for example, screws as indicated at 44, for retaining the magnet means 36 in the magnet receiving cavity 38.The latch member 34 is part of a latching means 14 which may be a manually operated deadbolt structure of conventional design and operation and is retained on the door 12 by, for example screws 16. The portions of such a deadlock structure not illustrated herein are not, per se, part of the present invention. The retention plate 40 as shown in FIG. 1 is only one type of retention means which may be utilized in the practice of the present invention. Thus, the retention means may comprise a layer of adhesive between the magnet means 36 and the walls 39. the retention means may be a force or interference fit between the magnet means 36 and the walls 39. The retention means may comprise a set screw extending radially through the latch member and engaging the magnet means 36. The magnet means 36 may be retained in the magnet receiving cavity 38 by a threading engagement of thread formed on the outer surface of the magnet means 36 and matching threads on the walls 39. The above described or other retention means may be utilized as desired in any combination in particular applications. The latch member 34 is reciprocatingly movable in directions indicated by the arrow 46 which, for the condition of the door 12 in the closed position, as described below in connection with the description of FIG. 3, allows a first portion 34a of the latch member 34 to move into and out of the latch member receiving cavity 24 of the jamb 18 with a second portion 34b of the latch member 34 remaining within the door 12. As shown on FIG. 2, the latch member 34 has the first walls 39 defining the magnet member receiving cavity 38 which is preferably circular in cross section having a first diameter indicated at A. The magnet means 36 is preferably a cylindrical magnet having an axial length substantially equal to the axial length of the magnet receiving cavity 38 and has a diameter indicated at B. In the first embodiment 10 the diameter B is less than the diameter A for reasons hereinafter set out, but, if desired, may be substantially the same diameter. FIG. 2 illustrates the first embodiment 10 with the door in the closed position thereof with respect to the door jamb 18 and the latch member 34 of the latching means 14 positioned in the latch member receiving cavity 24. In the closed position shown in FIG. 2, the magnet means 36, is in switch operating relationship to the switch means 30. The switch means 30 may be hard wired to a source of electricity (not shown) or may be powered by a battery 50 and placed into operative or inoperative condition by a control switch 52. When the magnet passes into switch operating relationship to the switch 30 and the switch 30 is in an operative condition, the switch 30 is "armed". If the magnet 36 is then removed from switch operating relationship to the switch 30, the switch 30 changes from a normally open to a normally closed condition (or normally closed to a normally open condition) which generates an information signal in the leads 56. The information signal so generated may be utilized in any indication means (not shown) such as a siren, bell or other auditory alarm, or in a status board showing that the particular door 12, which may be one of many similar doors in, for example, an apartment complex, located at a security guard's desk. In any event, upon detection of the information signal, appropriate remedial action may be taken if the attempted entry is unauthorized. For authorized entry, a conventional disabling means (not shown) may be incorporated into the circuitry so that no signal is generated when the magnet moves out of switch operating relationship to the switch. FIGS. 3 and 4 illustrate a second embodiment consistent with the present invention generally designated 58 in which a latch member 34' of a latching means 14' which may be a deadbolt is provided with a thin disc magnet 60 retained in the latch member 34' adjacent the forward face 42' thereof. The disc magnet 60 is retained in the latch member 34' by retaining plate 62 by screws indicated at 44. Mounting plate 21' is part of the latching means 34' and is held in place on the door 12' by screws as indicated at 16 in the same manner as the mounting plate 21 is mounted on the door 12 in the, first embodiment 10 described above in connection with FIGS. 1,2 and 3. The magnet 60 operates to control a switch means (not shown) in a manner similar to the action provided by the magnet 36 of the first embodiment 10. FIG. 5 illustrates a third embodiment consistent with the present invention generally designated 80 of a latching means 14" having a latch member 82 which may be, for example, a deadbolt. The forward face 84 of the latch member 82 is coated with a rubberized magnetic coating 86 to act as the magnet within the principles of the present invention. In other embodiments of the present invention, a plurality of magnetically operated switches similar to switch means 30 may be utilized and placed in the door jamb as shown for the switch means 30 so that a plurality of information signals may be utilized for a variety of detection means. For a magnet means 36 installed in a magnet receiving cavity 38 as described above in connection with FIGS. 1, 2 and 3, the smaller diameter of the magnet means 36 provides additional security. As shown in FIG. 2 there is generally a space indicated by D between the outer edge surface 12a of the door 12 and the outer edge surface 18a of the jamb 18. If a sawing instrument is placed in the space D and an attempt is made to cut through the latch member 34, it will not be possible to cut completely therethrough. In some embodiments consistent with the invention the magnet means 36 will rotate in the cavity 38 and not allow the saw to cut therethrough. The magnet means 36, in other embodiments, may be fabricated from any desired hardened magnet material to aid in the saw resistance properties thereof. Further, in such embodiments, the magnet means 36 for the condition of the door in a closed condition and the latch member 34 inserted into the latch member receiving cavity 24 of the jamb 18 has a portion indicated at 36a in the space D and preferably a portion 36b in the door 12 so that it is insured that the portion 36a is in the space D. FIG. 6 illustrates a fourth embodiment consistent with the invention generally designated 90 in which the latching means 92 is the conventional handle operated type having a latch member 94 with a tapered face 96 which slidingly engages a strike plate (not shown) on a door jamb. The latch member 94 has first walls 98 defining a magnet means receiving cavity 100 in which a magnet 102 is positioned. The magnet 102 is held in place by a snap ring 104 abutting against shoulder 106 of magnet 102. The snap ring 104 is contained in snap ring groove 110 defined by snap ring groove walls 112. The magnet means 102 may be rotatable mounted in the cavity 100 in a manner as described above for the magnet 36 of the first embodiment 10 or may be fixed in place as desired for particular applications. FIG. 7 illustrates a fifth embodiment 120 of the present invention as utilized in a vertically moving lock bar arrangement. The vertically moving lock bar 122 may be of the type often employed in double door applications or in push bar operated door applications. The lock bar 122 moves reciprocatingly in the vertical directions indicated by the arrow 124. The outer end 122' of the lock bar 122 moves into and out of the cavity 126 formed by walls 128 in header 130 which, in many applications is formed by doubled 2 by 4's 130a and 130b. A magnet means 132 which may be similar to the magnet means 36 described above, is positioned in the lock bar 122 and has a face 132a in regions adjacent the outer surface 122a of the lock bar 122. In the embodiment 120, the magnet means 132 is retained in the lock bar 122 by retention means comprising a force or interference fit, though any of the other retention means as described above may also be utilized in particular applications. A switch 134 which may be similar to the switch 30 described above is mounted in the header 130 so that the magnet means 132 passes in switch operating relationship when the outer end 122' of the lock bar 122 is positioned in the cavity 126. If the lock bar is then removed from the cavity 126, the switch 134 changes from, for example, a normally open to a normally closed condition to generate the desired information signal. The information signal may be utilized as described above. In any of the embodiments of the present invention, the entire latch member, whether a dead bolt, lock bar, spring loaded latch, or the like, may be a magnet depending on the particular application in which the invention is to be utilized. This concludes the description of the preferred embodiments of the present invention. From the above it can be seen that an improved security door lock has been provided which requires minimal redesign of existing hardware and is readily adaptable to mass manufacturing of presently available lock hardware and minimal changes in door installation. Those skilled in the art will find many variations and adaptations of the structure shown and described herein. The following claims are intended to cover all the variations and adaptations falling within the true scope and spirit of the invention.

A security lock for a door type structure in which a latch extends between the movable door and the fixed jamb. A magnet is contained within the latch and a switch is positioned in the jamb. The magnet passes into switch operating relationship to the switch for the condition of the door closed. When the magnet is moved out of the switch operating relationship to the switch, which occurs prior to the door being opened, the change in the magnetic flux causes the switch to generate an information signal which indicates that an attempt to open the particular door has been made.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION 1. Field of the invention This invention relates in general to electrical connectors, and in particular to an electrical connector for interconnecting submersible pump tandem motors. 2. Description of the Prior Art In an electrical submersible pump installation using tandem motors, the pump and two motors will be located in the well and suspended on a string of tubing. A power cable will extend down through the casing of the well alongside the tubing. An electrical connection connects the power cable to the upper electrical motor. Another electrical connection connects the lower end of the upper motor to the upper end of the lower motor. The motors and the electrical interconnection between the motors are filled with an insulating and lubricating oil. The prior art electrical connectors work sufficiently well. However, improvements are desired. For example, in the prior type, if water leaks into the upper motor, the water may gravitate downward and into the electrical interconnection. There is no means for disposing off any water that might collect in the receptacles of the electrical connectors. Moreover, there is no easy means for bleeding off any trapped air that is displaced upward as the lower motor is filled from the bottom with the lubricating oil during assembly. In the prior art, each metal connector sleeve assembly and each metal connector pin assembly is a two piece design. These two piece designs utilize metal threaded members which are tightened against portions of insulators. These connections tend to loosen with time due to cold flow of the insulators. SUMMARY OF THE INVENTION In this invention, the electrical connector between the tandem motors utilizes insulators which are internally threaded, unlike the prior art insulators which had smooth, unthreaded bores. Each metal connector member is of a single piece design, having a wire joined to one end. Each metal connector member is threaded for securing in the threads formed in the insulator. Also, each metal connection member has a vertical slot or channel that extends through the threads. This channel allows trapped water to bleed downward and out of exposure to the electrical contacts. The channel also allows displaced air to pass upward through the electrical connections during filling of the motors with oil. BRIEF DESCRIPTION OF THE DRAWING The sole figure is a quarter sectional view of a portion of an electrical connector constructed in accordance with this invention for connecting between electrical submersible pump tandem motors. DETAILED DESCRIPTION OF THE INVENTION The motor head electrical connector has a head or female body 11 which has an axial passage 13 through which the motor shaft (not shown) extends. Body 11 secures to the upper end of a lower tandem motor (not shown). Passage 13 is enlarged at its upper end, resulting in an inner cylindrical wall 15. A base 17 locates at the lower end of inner cylindrical wall 15. Base 17 is an annular shoulder encircling passage 13 and facing upward. A plurality of holes 19 (only one shown) extend through base 17. Holes 19 are parallel to passage 13 and evenly spaced around passage 13. Normally, there will be three holes 19, one for each phase of three phase AC power. A female insulator 21 locates within each hole 19 Each female insulator 21 is of an insulating material and has an axial passage 23 extending completely through it. The upper portion of passage 23 is enlarged, defining a receptacle 25. Receptacle 25 extends above base 17. A set of threads 27 locate directly below receptacle 25 within a reduced midsection area of passage 23. The lower portion of passage 23 is of larger diameter than the threads 27. This results in a downward facing shoulder 29 located within the lower portion of passage 23. The upper end of threads 27 is a selected distance below receptacle 25, resulting in a smooth pilot bore 28 in passage 23 immediately above threads 27. Each female insulator 21 has an external flange 31 that locates within an enlarged portion at the upper end of hole 19. A retaining ring 33 locates above flange 31 to secure each female insulator 21 to the female body 11. Retaining ring 33 may be secured to base 17 by fastener means such as screws (not shown). A connection sleeve 35 secures within each female insulator 21. Connection sleeve 35 is a metallic conductor. Connection sleeve 35 has external threads 37 that screw into internal threads 27 in the female insulator 21. The upper end of the external threads 37 locates at the lower end of pilot bore 28. A smooth cylindrical portion of connection sleeve 35 fits tightly in pilot bore 28, with the upper end of connection sleeve 35 being flush with the bottom of receptacle 25. Connection sleeve 35 has a receptacle 39 within it that has a closed bottom. Connection sleeve 35 also has a socket 41 on its lower end. One of the electrical wires 43 will insert into socket 4 and will be joined to socket 41, preferably by soldering. Electrical wires 43 extend downward to the lower tandem motor (not shown). A vertical channel 45 extends along the exterior sidewall of connection sleeve 35. Channel 45 extends completely from the upper end to the lower end of connection sleeve 35, passing through threads 37. Channel 45 allows any water migrating downward from the upper motor to flow downward past threads 37. Channel 45 also allows upward flow of displaced air during filling with oil. The electrical connector also includes a base or male body 47 that attaches to the lower end of an upper tandem motor (not shown). Male body 47 secures to female body when the tandem motors are connected together. Male body 47 has a longitudinal passage 49 through it that will be coaxial with passage 13 of female body 11 once connected. The shaft of the motors (not shown) will extend through passage 49. Male body 47 has an external cylindrical wall 51 that inserts within cylindrical wall 15 of female body 11. A pair of O-ring seals 53 located on an external cylindrical wall 51 seal against inner cylindrical wall 15. A base or downward facing shoulder 55 locates at the upper end of external cylindrical wall 51. A plurality of holes 57 (only one shown) are spaced around shoulder 55, each in alignment with one of the holes 19 in female body 11. A male insulator 59 locates within each hole 57. Male insulator 59 has a downward protruding mandrel 61 that is cylindrical and sized for tight close reception within receptacle 25. An axial passage 63 extends completely through male insulator 59, providing an opening at the lower end of mandrel 61. A plurality of threads 65 are located in passage 63 in the portion of passage 63 located within mandrel 61. The lower end of threads 65 is spaced above the lower end of passage 63, resulting in pilot bore 66 portion of passage 63 that is cylindrical and smooth. Passage 63 has an upward facing shoulder 67, separating the portion of passage 63 that is in mandrel 61 from the portion above. Male insulator 59 has an external flange 69 that fits within a circular recess in shoulder 55. A retaining ring 71 secures the male insulators 59 in place by abutting against the flanges 69. Screws (not shown) secure the retaining ring 71 to the shoulder 55. A metal connection pin 73 secures within each passage 63. Connection pin 73 has a split pin on its end that protrudes past mandrel 61 for insertion within receptacle 39. Connection pin 73 has a flange 75 that is external for abutting against shoulder 67. External threads 77 on connection pin 73 will engage threads 65 to secure connection pin 73 in male insulator 59. A socket 79 locates on the upper end. A wire 81 will be joined to socket 79, preferably by soldering. Although not visible in the drawing, pin 73 protrudes past the lower end of mandrel 61 slightly less than the depth of receptacle 25. This assures that the mandrel 61 will enter receptacle 25 before the pin 73 enters receptacle 39. A vertical or axial extending channel 83 extends along one side of the exterior of connection pin 73, completely through the threads 77. Channel 83 will allow any water migrating downward from the upper motor to flow through mandrel 61 and downward through channel 45. Channel 83 also allows air to bleed during filling of oil in the motor. Male body 47 secures to female body 11 in a conventional manner. A plurality of bolts 85 secure the bodies 11, 47 together. Bolts 85 engage threaded holes 87 in female body 11. Bolts 85 extend through a flange 89 that is on the exterior of male body 47. Bolts 85 will pull the flange 89 into abutment with a rim 91 located on the upper end of female body 11. During assembly, the female body 11 will be secured to the upper end of a lower tandem motor. The male body 47 will be secured to the lower end of an upper tandem motor. The motors will be connected together by securing the male body 47 to the female body 11. During this process, the pins 73 will be aligned with the sleeves 35. The male body 47 is pushed toward the female body 11. Tightening bolts 85 pulls the flange 89 into engagement with rim 91. Insulating oil is pumped into the assembled tandem motors from the lower end of the lower tandem motor. As the oil flows upward, it will displace air. Any air trapped below female connection sleeves 35 will flow upward through channels 45 and 83. The connection pins 73 and sleeves 35 will be completely immersed in oil. During operation, power for the lower motor is supplied through the electrical connection pins 73 and sleeves 35. If water enters the upper motor and migrates downward into the passages 63 of the male insulators 59, the water will flow downward through the channels 45, 83, out of contact with the connection sleeves 35 and pins 73. The invention has significant advantages. The channels allow any water and air to be displaced out of the area of the electrical contacts. Securing the electrical contacts directly into threads in the insulators makes them less subject to being loosened with time due to cold flow of the insulators. The connection sleeves and connection pins are one piece, allowing fewer parts for the assembly. Fewer components also reduces the chance for loose electrical connections. The electrical connector is easier to assemble than the prior art type. While the invention has been shown in only one of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention.

An electrical connector for interconnecting tandem motors of an electrical submersible well pump utilizes single piece metal pins and sleeves. Each half of the connector has insulators located in the body. Metal connection sleeves are located in holes in the insulators. The connection sleeves have threads for securing to threads formed in the insulators. The metal connection pins also have threads for securing to threads formed in the insulators. The connection sleeves and connection pins have axial slots formed on their exteriors.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION This invention relates to closets such as school lockers. BACKGROUND OF THE INVENTION Vandalism, i.e. the willful partial or complete destruction of public or private property, is, it would seem, an increasing problem in industrial countries, or is at least increasingly reported by information media (newspapers, television news broadcasts, . . .). More specifically, the recently unveiled data for yearly reparation costs of public school equipment, particularly personal lockers for high-school students in Canada, indicate that large amounts of money are involved, and provides a troubling insight of the violence developed by adolescents. For instance, in one very large high-school public institution in downtown Montreal, yearly repair costs for personal lockers alone have been reported to be in excess of half a million dollars. It is believed that part of the problem associated with vandalism is linked to the easinees in obtaining the satisfaction of seeing the object sustaining the physical abuse rapidly destroyed. Indeed, psychology would show that physical abuse on public property provides an outlet for aggressive tendencies of adolescent youths, and a feeling of "success" or great satisfaction comes from becoming aware of the physical strength by the youth through deformation of the structure of the lockers. To the inventor's knowledge, no significant attempt has been made by closet manufacturers to mass-produce a low-cost yet significantly reinforced locker, specifically for high-school use. Should there be lockers of stronger construction in schools it would be much harder for the students to poke or deform same and thus, a reduced level of satisfaction would result. However, the urge to vandalize property would not disappear, it would only be shifted elsewhere. Of course, the basic problem remains at a psychological level, since the physical violence is only a symptom of a condition. Unfortunately, further elaboration of these considerations goes beyond the scope of the present invention. OBJECTS OF THE INVENTION The prime object of the invention is thus to discourage vandalism by considerably reinforcing the structure of closets such as school lockers. A corollary object of the invention is to increase the durability of closets. Another object of the invention is to significantly decrease the maintenance costs of public property in high-schools, mainly public schools but also private one as well. An object of the invention is to provide a locker as above-described, which is of particularly low cost. Another object of the invention is to provide foldable seat means which can be fitted inside the closet. An object of the invention is to provide key means and door lock means to enable controlled access to said closet. A further object of the invention is to provide handle means to enable a person trapped inside the locker being locked from the outside by the door lock means, to escape from the locker. SUMMARY OF THE INVENTION In accordance with the stated objects of the invention, there is disclosed a closet for use as a locker for storage of items such as clothing, school books and the like, consisting of: (a) a closed, hollow, rigid frame, defining a front wall, at least one door wall opening being made into said front wall; (b) a rigid door for each said door wall opening, said door being of substantially semi-cylindrical shape; and (c) mounting means, for securing said door to said frame whereby said door is movable relative to said frame between a closed position, completely closing said door wall opening so as to be convex when viewed from the outside, and an open position, substantially clearing said door wall opening. The door is releasably locked in its closed position, said mounting means thereafter becoming beyond reach. Said closed closet being characterized by its resistance to physical abuse. Preferably, said closet has top and bottom walls and said mounting means includes: (a) an upper disc member, having an upwardly-extending transverse shaft rotatably mounted to said top wall spacing the upper disc member from the top wall; (b) a lower disc member, having a downwardly-extending second shaft rotatably mounted to said bottom wall spacing the lower disc member from the bottom wall and said second shaft is coaxial to said first shaft; and (c) securing means, for anchoring said disc members to said semi-cylindrical door, wherein the latter is rotatable about a common axis of said first and second shafts, and wherein the door opening action shifts the door inside said closed frame to completely disappear therein so as to be concealed. The opened door will be much less likely to sustain physical abuse from would-be vandals when in said closed frame. The disc members are saucer-shaped, each defining upturned, curved, peripheral flanges with about a half section being anchored to said door by anchoring means. Preferably, said saucer-shaped disc members each have a number of through-bores, for passage of water therethrough, whereby these disc members can be used as shelves for supporting clothing (which may be soaked). It is envisioned that the top face of said closet bottom wall be downwardly inclined or sloped, and further including at least one water drain hole in the front edge section of said closet bottom wall; whereby said disc members through-bores, said closet sloped bottom wall and said drain hole cooperate in evacuating water from said closet. A large U-shape bracket is made to depend from the underface of said upper disc member, for engagement by one or more coat-hangers for hanging garments. Advantageously, said closet frame is made from concrete, said top and bottom walls being physically separate from the remaining closet frame but fixedly secured thereto by a number of bolts and nuts, said bolts engaged in countersunk holes in said top and bottom walls, said nuts cavities in said remainder of the closet frame. Preferably, each door is reinforced by being made from corrugated metal. It is envisioned that there be at least two door wall openings and a corresponding number of doors, and further including at least two cylindrical storage areas each being constituted within the volume defined by a given semi-cylindrical door, the relative position of said door with respect to its sliding motion run and the length thereof being such that each said storage area remains constantly beyond reach of any adjacent storage area(s). The length of each door is about 5/4 πR, where R is the radius of curvature of the door around the saucer-shape disc members. Preferably, said closet separate concrete bottom wall is anchored to the ground by further bolt means, mounted into a well or cavity made into the side edge of said bottom wall. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an assembly of three interconnected lockers constructed in accordance with the teachings of the invention; FIG. 2 is a top plan view of the locker assembly; FIG. 3 is a vertical, sectional view of one locker, taken along line 3--3 of FIG. 2; FIGS. 4-5 are views of the areas circumscribed by circles 4 and 5 respectively of FIG. 3; FIG. 6 is a cross-sectional view of the locker assembly, taken along line 6--6 of FIG. 3; FIG. 7 is a view of the area circumscribed by circle 7 in FIG. 1; FIGS. 8-9 are perspective views of the top and bottom wall members of one locker, the wall in FIG. 9 being partly broken away; FIG. 10 is a partly broken away, front, elevational view of a locker according to the invention; FIG. 11 is a front, elevational view of the exterior concrete frame portion enclosing one locker of the invention; FIG. 12 is an enlarged view of the area circumscribed by circle 12 in FIG. 6; FIG. 13 is a view of the area circumscribed by circle 13 in FIG. 3; FIG. 14 is a broken away, sectional elevation similar to FIG. 3, but showing a preferred door lock release mechanism to be operated within the closet; FIG. 15 is a view of the area circumscribed by circle 15 of FIG. 14; FIGS. 16 and 16a are views of the area circumscribed by circle 16 in FIG. 14, sequentially showing how the handle of the door lock release mechanism can be manually actuated; FIGS. 17, 17a, 17b, 17c are cross-sectional views taken along lines 17--17 of FIG. 14, showing how the door lock release mechanism operates in different conditions; FIG. 18 is a partial sectional view of the lever means of the door lock release mechanism, taken along broken lines 18--18 of FIG. 17c; FIG. 19 is a schematic view of the door lock release mechanism; FIGS. 20-20a are broken away, vertical sectional elevations of the closet lower section, but showing a first embodiment of seat means sequentially illustrated in its inoperative and operative conditions; FIGS. 21-21a are top plan views of the elements in FIGS. 20-20a respectively, from under the intermediate saucer-shape shelf; FIGS. 22-22a are views similar to that of FIGS. 20-20a but for a second embodiment of seat means; FIG. 23 is a top plan view of the elements of FIG. 22, from under the intermediate saucer shape shelf; FIG. 24 is a front elevational view taken from line 24 of FIG. 22a; FIG. 25 is a view of the area circumscribed by circle 25 in FIG. 24; FIGS. 26-26a and 27-27a are views similar to that of FIGS. 20-20a and 21-21a but for a third embodiment of the seat means; FIG. 28 is a view similar to that of FIG. 20, but for a fourth embodiment of the seat means; FIGS. 29 and 30 are a top plan view and a front elevational view respectively of the elements of FIG. 28; and FIG. 31 is a partly broken away, perspective view of a rail member forming part of the seat means of FIG. 28. DETAILED DESCRIPTION OF THE INVENTION Locker assembly 20 shown in FIGS. 1-2 and 6 includes a concrete, ground-supported frame 22 enclosing three cylindrical, upstanding, storage areas 24, 26, 28 which transversely open into each other, and semi-cylindrical metallic doors 30, 32, 34 being mounted to the front of frame 22 for gaining access to the storage areas 24, 26, 28 respectively. Frame 22 defines three separate sections: (a) a main section, consisting of a large, vertical, rear wall 36 (FIG. 3) and two side walls 38, 40 edgewisely mounted integrally to the rear wall orthogonally thereto; (b) a top wall member section 42, edgewisely abutting against walls 36-40; and (c) a bottom wall member section 44, edgewisely supporting walls 36-40. Top wall member 42 includes a peripheral downturned flange 46, and bottom wall member 44 includes a peripheral upturned flange 48. Each flange 46, 48 includes a plurality of spaced, lengthwise countersunk-bores 50, 52 (FIG. 4) for bolts 54. Walls 36-40 have in turn a plurality of threaded bores 56, 58 at their top and bottom edges, into each of which bores is threadedly, lockingly engaged a nut 60. Each top bore 56 is destined to register with a selected top countersunk-bore 50, and each bottom bore 58 is destined to register with a selected bottom countersunk-bore 52, wherein the respective bolts 54 are to engage the corresponding nuts 60, anchoring top and bottom wall members 42, 44 to the main frame section 36, 40. Preferably, bottom wall 44 is downwardly forwardly inclined, and the front section 48a of lower flange 48 includes a corner drain hole 62, for escape of water from the flooring 44 of the lockers 24, 26, 28. As clearly illustrated in FIGS. 3 and 10, each locker 24, 26, 28 includes a circular strut or shelf members 64, 66, 68, around which is mounted, e.g. by welding, a quadrangular curtain or door member 70. Each curtain 70 extends for slightly more than half the periphery of lockers 24-28, wherein a vertical mouth 71 is defined (FIG. 6). Each strut or shelf 64-68 defines a saucer shape, i.e. a flat disc portion 64a-68a with an annular peripheral flange 64b-68b. Three saucers 64-68 are provided. Each have upwardly-inclined flanges 64b-68b. More particularly, the top saucer 64 is connected to the top wall 42 by a stem 74. The stem has a screw at its bottom edge 76 engaging the center of disc 64a, and rotatably engaged at its top end 78 within a bushing 80 which is embedded into wall 42. The stem 82 of lower shelf 66 is similarly anchored to central area 72 of disc 66a and rotatably mounted into a block 84 embedded into bottom wall 44, the plane of block 84 being offset relative to that of sloped flooring 44 so as to support stem 84 vertically, see FIG. 3 at the bottom. Bottom shelf 68 is also mounted to stem 82, between shelf 66 and flooring 44, by having the stem 68 extend through the center of the disc, and welded thereto at 86, at a suitable position spaced from the overlying saucer-shaped shelf 66. Flanges 64b-68b constitute circular guides for the curtains 70 to which the curtains are fixedly secured e.g. by welding. Moreover, these shelf members can be used as vertically-spaced trays for supporting clothing, school books, and like items which items are easily accessible when the door is opened. It is envisioned that the discs 64a-68a have a few through-bores 88 enabling water to escape from soaked clothing and drip down to flooring 44. The flooring 44 is sloped therealong, to allow water to escape from the locker assembly 20 through front outlet ports 62 (one for each storage areas 24-28). These flanges 64b-68b are also reinforcement means, for reinforcing the cylindrical structure of the door or curtain 70. There is also a rigid, reinforcing collar member 92, on the inner face of curtains 70 intermediate shelves 64 and 68. As shown in FIGS. 6 and 12, each curtain 70 is preferably corrugated, i.e. wavy in cross-section, to reinforcing the curtain and to discourage vandalism. Each door should further include a transverse handle 94 on the exterior face thereof, at mid-height, for maneuvering the door in its lateral sliding action between a closed position, shown in FIG. 1 as closing the front opening of casing 22, and an opened position clearing said front opening for access to storage areas 24, 26 or 28. Doors 30-34 are anchored by the flanges 64b-68b of their respective saucer-shaped struts 64-68, and their bottom edges extend above flooring 44. The front edge sections of the top wall member 42 and the bottom wall member 44 should be formed with semi-circular projections 42a, 44a corresponding to the number of lockers 24-28. The projections conform to the exterior convex shape of the doors 30-34, see FIG. 1. Of course, the fact that the closed doors 30-34 are convex (when viewed from the outside) increases still more the structural integrity of the locker assembly 20 and thus its resistance to physical abuse (e.g. kicks or other blows thereagainst) from would-be vandals. It should be understood that, although an assembly 20 of three interconnected lockers has been shown as a preferred embodiment two, four or more interconnected lockers could benefit as well from the teachings of the invention. Thus when there is more than one locker, wooden beams or the like 96 should be added vertically between each pair of doors, e.g. 30 and 32, and 32 and 34 in FIG. 1, and anchored by bolts 54 (FIG. 2) to the top and bottom walls 42, 44 preventing sidewise access to the storage areas 24-28. As shown in FIG. 6 the length of the doors 30-34 and their positions relative to each other require that one locker storage area (24, 26 or 28) should never be accessible from the adjacent areas. Thus, in the embodiment of FIG. 6, the length of a door is about 5/4 πR, where R is the radius of curvature of the door around the saucer-shaped shelves 64-68 and the door surrounds for more than half the peripheral edge of these shelves. The first two closed doors 30, 32 must extend into casing 22 to the right thereof, with the corresponding handles 94 being at the left, while the last closed door 34 must extend into casing 22 to the left thereof with the corresponding handles being at the right. The handle of door 30 abuts against the front edge of wall 38, the handle of door 34, against the front edge of wall 40, and the handle of door 32, against the wooden beam 94 (FIG. 12) extending between doors 30 and 32. The wooden beams 96 constitute a front wall for locker assembly 20. Each handle 94 is to releasably secured to a bracket 97, anchored to walls 38, 40 and 96 when the corresponding door is closed, by any conventional padlock (not illustrated), in the known fashion. It is envisioned that the concrete base 48 of locker assembly 20 will be anchored to the ground by bolts 98 (FIG. 7) mounted in a cavity well 100 of wall 48 and opening outwardly thereof, wherein screwing/unscrewing thereof is possible with a ratchet tool. Emergency door unlocking and opening means 110 shown in FIGS. 14-19 includes a cable 112, slidably mounted into an elongated sheath 114 which extends vertically along the inner face of the rear section of door 70 and forwardly therefrom at the top and bottom edges thereof. The cable 112 is to be secured at both ends to springs 128, 130 themselves secured to top and bottom walls 120, 122. Sheath 114 is itself anchored (e.g. glued) to movable door 70. A small section of sheath 114a is sectionally made independent from the remainder thereof and from door 70 (no glue at this section 114a), wherein by pulling section 114a cable 112 will be pulled in equal increments at the top and bottom sections thereof, thanks to the play provided by said anchor members 116, 118 (as will be detailed below). Sheath section 114a is preferably preformed into a U-shape, so as to constitute a handle facilitating handling thereof, see FIGS. 16-16a. Top and bottom partitions 120, 122 are edgewisely mounted to door 70 for rotation therewith around vertical posts 124, 126. Sheath 114, including cable 112, extends through apertures 120a, 122a made in partitions 120, 122. The ends of cable 112 are secured to coil springs 128, 130 themselves anchored to partitions 120, 122 via anchor pins 132, 134. A supplemental cable section 136, 137 is added to each cable end section spacedly from springs 128, 130 and anchored at its outer end to a plunger 138, 140. Each plunger 138, 140 is part of an electro-magnetic coil or solenoid 142, 144 which are anchored to the top and bottom faces of partitions 120, 122 respectively. Plungers 138, 140 are biased by a coil spring 141, 141a, to engage cavities 146, 148 made concrete casings 96 proximate the door opening 150 to automatically lock the door upon closing the same. To unlock the door, a magnetic card 151 is inserted within a box 153 and the card reader actuates a switch in box 152 for closing the circuit to the solenoids 142, 144 which retract the plungers 138, 140 against the action of coil springs 141. This door locking mechanism is conventional. Wires 143 leading to the solenoids 142 are coiled to permit rotation of the solenoid operated plungers with the doors 30, 32 or 34. Idle rollers 154, 156 are rotatably dependent from the top and bottom faces of partitions 120, 122, proximate posts 124, 126 respectively, and substantially coaxial with the posts. Cable 112 tangentially engages rollers 154, 156 under tension from springs 128, 130, while cable sections 136, 137 are loose when handle 114a is released. Plungers 138, 140 will automatically engage into concrete casing top and bottom cavities 146, 148 when the door 70 is swung to its closed position, thanks to bevels 138a, 140a at the free ends of plungers 138, 140 and to bevels 96a on the inner walls of concrete front wall section 96. Indeed, if the door 70 is closed with some force, the plungers 138, 140 will strike with some speed bevelled walls 96a laterally with their top and bottom bevelled edges 138a, 140a thus temporarily retracting against the bias of springs 141, 141a. Once plungers 138, 140 register with cavities 146, 148, they will engage therein, so as to lock door 70 in closed position, while a door stopper 158 will concurrently abut against the front edge 38a of concrete wall 38. When handle 114a is pulled, e.g. by someone trapped inside the locker, cable sections 136, 137 will be tensioned around rollers 154, 156 and will pull plungers 138, 140 outwardly from cavities 146, 148 against the bias of springs 141, 141a thus enabling the opening of door 70 (FIG. 17b). If someone cuts the cable 112 and then tries to trap another person inside the locker, there is means to prevent door locking. These means includes spring 128, in combination with a lever 160 which is pivotally carried at 162 by the top face of wall 120, between of the axis joining post 124 and solenoid 142 relative to spring 128. The lever 160 is connected at its outer end to the inner end of spring 128. Lever 160 includes a transverse notch 164 for free passage of cable segment 136 but is in the path of plunger 138. A hook 166 is anchored to partition 120 proximate door 70, in between solenoid 142 and pin 132. Hook 166, as shown in FIG. 18, consists of an elongated, flexible resilient metal blade fixed to top wall 120 parallel to plunger 138 and having a bent outer section 166a i.e. spacedly diverging by about 30° from wall 120. The free end section of blade 166 at 166b is upwardly bent so as to make an acute angle with leg 166a. Bent section 166b should not normally come in contact therewith because the length of cable 112 is such as to keep lever 160 away from hook 166 despite the tension of springs 128 and 130. However, should cable 112 be cut, the spring 128 will then retract and pull on the outer end of lever 160 which will transversely slide along the top face of flexible blade leg 166b. The latter will then downwardly yield (dotted lines in FIG. 18) and will thereafter return to its raised position (full lines in FIG. 18) to hook on lever 160, so that it remains substantially orthogonal to and transversely abutting against plunger 138 to lock the latter into an outward position. Thus, even if the door 70 is forcibly swung toward its closed position, the plunger 138 striking concrete edge 96a will not retract and one will not be able to close the door. The locker may be provided with a seat which folds within the locker when not in use. Various seats are suggested in FIGS. 20-31. In FIGS. 20-21, 20a-21a, there is shown a foldable seat 170 carried by a pivot arm 174 which is integrally connected to a sleeve 176 rotatably mounted around lower post 126. Panel assembly 172 includes: a circular wooden panel 178, anchored to a cylindrical body 180; a rod member 182, anchored at one end to the pivot mount 184 of pivotal arm 174, and slidably engaged within cylinder 180; and a foot 186, transversely anchored to panel 178 in outwardly divergent fashion. Arm 174 may pivot from a retracted position shown in FIG. 21 to an extended position shown in FIG. 21a. Cylinder 180 may slide along rod 182 from an inner position shown in FIG. 21, to a fully extended condition shown in FIG. 20a where it extends outwardly of the locker. Seat panel 178 may pivot from a vertical inoperative position (FIG. 20) to a horizontal operative position (FIG. 20a), where it is supported over ground by leg 186. A pin (not shown) fixed to sleeve 180 engages a longitudinal groove made in rod 182 and communicating with an annular groove in rod 182 to limit extension of sleeve 180 while permitting its rotation at the end of its extension. Leg 186 in its inoperative position is parallel to floor 122, as shown in FIG. 20. The seat assembly, when in folded stored position, is within the confines of a compartment defined by the lower portion of door curtain 70 and of floor 122 and shelf 68 fixed thereto. The door can therefore be closed. In the second embodiment of seat means 190 shown in FIGS. 22-25, 22a, seat panel 178 is flatly anchored to one end section of a cross-sectionally C-shape rail member 192, which, as best shown in FIG. 25. Rail member 192 is slidably engaged around a cross-sectionally quadrangular bar 194. Member 192 carries a pin 193 engaging a longitudinal blind groove 194a in bar 194 to prevent disengagement of members 192. An end section of bar 194 is pivotally carried to the top end of post 126 by a pivot mount 196, for pivotal motion about a horizontal axis. Thus, tube 192 is slidable from an inner position shown in FIG. 22 to a fully extended condition shown in FIG. 22a, along bar 194. The wooden panel 178 and foot 186 are not pivotable, thus they take more storage space in the locker than the first seat means 170 of FIGS. 20, 21. Foot 186 may be V-shape, as shown in FIG. 24. In the third embodiment of seat means 200 shown in FIGS. 26, 27, 26a, 27a, the post 126' journalled within concrete base 44 and fixed to floor 122 is much shorter, to give more space upward, and a pivotal arm 202 is mounted at one end to post 126' and at the other end to a rod 204. Rod 204 is anchored at its outer end to seat panel 178. Pivot mounts 202a, 202b of arm 202 enable relative motion of arm 202 and rod 204 about horizontal axes. The extension of seat means 200 from its retracted position of FIG. 26 to its fully extended position of FIG. 26a is permitted solely by the pivotal motion of lower arm 202 by almost 90°, while rod 204 remains substantially horizontal. Abutment plate 203 fixed to arm 202 abuts a flange 205 fixed to rod 204 in the extended position of the seat assembly to maintain seat 178 horizontal and leg 186 vertical. In the last embodiment of the seat means 210 shown in FIGS. 28-31, a wooden panel 178 is carried by a U-shape foot 186. Bottom ends of the legs 211, 213 of the foot are anchored to two spaced horizontal tubular bars 220. These bars 220 are slidably engaged into hollow tubular members 216, 218 which are anchored to flooring 122 substantially parallel to concrete wall 38 when the door is fully opened. The foot legs 211, 213 engage through slits 216a, 218a made in the top walls of anchor elements 216, 218. A bar 224 is slidable within tube 220. The panel 178 remains horizontal in its inoperative and operative positions. Each tubular member 220 has a transverse finger 222 engaging a longitudinal groove 226 of a bar member 224 for limiting extension of tube 220 relative to bar 224. A stop 228 is fixed to the inner end of tube 224 and abuts anchor tubes 216, 218 in the fully retracted position of tube 224. Tube 224 reinforces the telescopic assembly such that the seat does not require a ground engaging leg.

A closet, for use as a locker for storage of items such as clothing, school books and the like, consisting of: a closed, hollow, rigid frame, defining top, bottom and front walls, at least one door opening being made in the front wall; a rigid door for each door wall opening, the door being of substantially semi-cylindrical shape; a first disc rotatably mounted to the top wall by a first stem; a second disc rotatably mounted to the bottom wall by a second stem, the second stem being coaxial to the first stem. The door fixed to and surrounding about a half edgewise section of the discs. The door is rotatable about the coaxial items, between a closed position completely closing the door wall opening so as to be convex when viewed from the outside, and an open position substantially clearing the door wall opening. The door is releasably locked in its closed position, the discs and stems thereafter becoming beyond reach. The closet is characterized by its resistance to physical abuse. The closet is provided with a low seat foldable therein. A system is also provided to unlock the closet from the inside.

You are an expert at summarizing long articles. Proceed to summarize the following text: TECHNICAL FIELD The present invention relates to the handling of a tubing string in a well bore and, in particular, to a locking telescoping joint for use in a conduit connected to a wellhead which permits the conduit to be axially displaced to a new position in the well bore without disconnecting the conduit from the wellhead and secured in new positions using the locking telescoping joint. BACKGROUND OF THE INVENTION Downhole operations and the handling of a tubing string in a completed well has always presented a certain challenge, especially when working in wells having a natural pressure. In Applicant's U.S. Pat. No. 5,957,198 which issued Sep. 28, 1999 and is entitled TELESCOPING JOINT FOR USE IN A CONDUIT CONNECTED TO A WELLHEAD AND ZONE ISOLATING TOOL, the specification of which is incorporated herein by reference, a telescoping joint is described for use in a conduit connected to a wellhead. The telescoping joint is adapted to support downhole well tools and to permit the downhole well tools to be axially displaced in the well bore without disconnecting the conduit from the wellhead. The telescoping joint is freely extendable and retractable. Downhole anchors or packers are used to support the conduit in the well bore. Although the telescoping joint has proven extremely useful and has generated significant commercial interest, it is not ideally suited for all downhole tasks and applications due simply to its freely extendable and retractable features. In order to extend the use of the telescoping joint into yet a broader range of applications, further improvement of the telescoping joint, particularly to enable releasably locking the telescoping joint at a selected extension, is desired. For example, production tubing strings are generally anchored at the bottom end to the cased well bore. The length of the production tubing string is usually between 1,500 and 5,000 m (5,000′-16,000′). Over time, a production tubing string will sag under its own weight because of the significant length. This is a disadvantage if a surface driven reciprocating pump is used for production because a sucker rod used to drive the pump may wear and bind in the sagging production tubing string. In order to overcome this problem, long production tubing strings are usually tensioned before production is started. The tensioning process involves unhooking the production tubing from the tubing hanger; pulling up the production tubing string to tension it to a desired extent; marking the production tubing string where it should be reconnected to the tubing hanger; preparing a pup joint having a length equal to a distance from the mark to a next joint in the tubing string; replacing the top joint with the pup joint and re-connecting the tubing hanger. This is a time consuming and expensive procedure that may require killing the well. It is therefore desirable to provide a tool for tensioning a tubing string without removing the wellhead from the well. There are also times when it is desirable to load a tubing string in compression. For example, if a downhole submersible pump is used for production, equipment costs can be reduced by using a less expensive compression packer to anchor the production tubing above the submersible pump. In order to ensure that the packer does not slip, it must be constantly loaded with compressive force. It is therefore desirable to provide a telescoping joint that permits a production tubing to be locked in compression. Latch assemblies and collet devices for interconnecting tubing members are well known in the art. Examples can be shown in U.S. Pat. No. 4,391,326 entitled STINGER ASSEMBLY FOR OIL WELL TOOL which issued to Dresser Industries, Inc. on Jul. 5, 1983; U.S. Pat. No. 4,513,822 entitled ANCHOR SEAL ASSEMBLY which issued to HUGHES TOOL COMPANY on Apr. 30, 1985; U.S. Pat. No. 4,681,166 entitled INTERNAL NONROTATING TIE-NECK CONNECTOR which issued to Hughes Tool Company on Jul. 21, 1987; and U.S. Pat. No. 4,722,390 entitled ADJUSTABLE COLLET which issued to Hughes Tool Company on Feb. 2, 1988. These patents generally describe an annular latch carried by an inner conduit having collet arms that are radially flexible and adapted to engage a latch point on an outer conduit. A relative axial movement between the two conduits is permitted in one direction only to permit threads of the collet arms to ratchet into or out of engagement with the threads of the outer conduit while the relative axial movement in an opposite direction is generally inhibited by the threaded connection to support a work load unless another manipulation is performed. However, none of these patents suggest a latch assembly to releasably lock a telescoping joint in a relative axial extension. Furthermore, these patents do not show or suggest a latch assembly having a plurality of latch points disposed along a travel length of a telescoping joint. SUMMARY OF THE INVENTION It is an object of the invention to provide a telescoping joint for use in a conduit connected to a wellhead to permit the conduit to be axially displaced and locked in the displaced position in the well bore without disconnecting the conduit from the wellhead. It is another object of the invention to provide a telescoping joint for use in a tubing string in a well bore, which includes a latch assembly for locking the telescoping joint at a predetermined axial extension. It is a further object of the invention to provide an apparatus for use in a tubing string in a well bore to maintain tension or a compression on the tubing string. It is yet a further object of the invention to provide a method of maintaining tension or compression on a tubing string in a well bore. In accordance. with one aspect of the invention a locking telescoping joint is provided for use in a conduit connected to a wellhead to permit the conduit to be axially displaced in the well bore without disconnecting the conduit from the wellhead. The locking telescoping joint comprises first and second telescopingly interconnected tubular sections having opposite ends adapted for connection to the conduit. A latch assembly is provided for releasably locking the first and second tubular sections in at least one position between a fully retracted and a fully extended position. Preferably, the latch mechanism comprises a first engaging member affixed to one of the tubular sections, and at least one second engaging member affixed to the other tubular section. The first engaging member is adapted to be releasably received in the second engaging member in order to lock the telescopic tubular sections in an axial position relative to each other. The latch mechanism may be any type of releasable engagement adapted to support the weight of a tubing string. For example, a J-latch, key, collet or slip type latch mechanism may be used. According to a first embodiment of the invention, the latch assembly includes at least one pin radially extending from one of the tubular sections and a plurality of axially spaced-apart slots defined in the other of the tubular sections. The slots are preferably interconnected by an axial groove adapted to serve as a passage route for the pin. According to another embodiment of the invention, one of the tubular sections includes a radially collapsible collet which can be manipulated between a collapsed condition for axial movement of the telescoping joint and an expanded condition for locking the telescoping joint at a predetermined extension, and the other of the tubular sections includes at least one cooperative latch point, the cooperative latch point being adapted to cooperate with the collapsible collet during the manipulation between the collapsed and expanded conditions. More specifically, one embodiment of the collet type latch mechanism includes a traveling collet which is adapted to be collapsed by the at least one cooperative latch point when forcibly moved past the latch point in either axial direction, and a locking collet which is adapted to be manipulated between a collapsed condition for axial movement of the telescoping joint and an expanded condition for locking the telescoping joint at a predetermined extension. In accordance with another aspect of the invention, the telescoping joint enables a method for maintaining tension or compression on a tubing string in a cased well bore. The method comprises the steps of: a) inserting a lift rod string into the tubing string which is attached at a top end to a wellhead and anchored at a bottom end to the cased well bore, the tubing string including a locking telescoping joint in the top end; b) latching the rod to a latch point of the telescoping joint; c) retracting or extending the telescoping joint to tension or compress the tubing string by manipulating the rod; d) and, locking the telescoping joint in the retracted or extended position using a latch assembly in the telescoping joint to maintain the tension or compression on the tubing string. The telescoping joint with the latch assembly in accordance with the invention provides improved functionality compared with the telescoping joint described in Applicant's issued U.S. Pat. No. 5,957,198 and is adapted for use in each application described in that patent. Furthermore, the selective extension locking feature enables the use of the telescoping joint to be extended to new applications, such as the above-disclosed examples of tensioning or compressing the tubing string in a cased well bore, as well as many others. For example, the locking telescoping joint in accordance with the invention can be used to reposition or otherwise manipulate downhole tools. Such tools include any one of a zone isolation tool, a packer, a hanger, a plug, a subsurface safety valve, and a downhole tool having a slip, collet, threaded or keyed locking engagement that is releasable and resetable by remote manipulation from a surface surrounding the well. Consequently, the time and cost of well completion and well maintenance are reduced as is the cost of production of hydrocarbons in wells with a mobile oil/water interface or other condition that requires periodic downhole maintenance. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be explained by way of example only and with reference to the following drawings, in which: FIG. 1 is a cross-sectional view of a telescoping joint including a latch assembly for use in a conduit connected to a wellhead in accordance with one embodiment of the invention; FIGS. 2-5 are schematic views of latch mechanisms in accordance with the first embodiment of the invention; FIG. 6 is a partial cross-sectional view of a latch assembly in accordance with another embodiment of the invention; FIG. 7 is a partial cross-sectional view of the embodiment shown in FIG. 2 illustrating the latch assembly in a locking condition; FIG. 8 is a partial cross-sectional view of another embodiment of a telescoping joint in accordance with the invention; FIG. 9 is a schematic cross-sectional view of a well bore with a hoisting apparatus installed on the wellhead for tensioning a production tubing string using a telescoping joint in accordance with the invention; and FIG. 10 is a schematic cross-sectional view of the well bore shown in FIG. 10 with a hoisting apparatus installed on the wellhead for placing a production tubing string in the well bore under compression using a telescoping joint in accordance with the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The invention provides an apparatus and method for using the apparatus for performing downhole operations in well bores which require the axial displacement of downhole tools and/or the axial displacement of well tubing in the well bore. The invention also provides a practical means for maintaining tension or compression on a tubing string in the well bore. FIG. 1 shows a cross-sectional view of a locking telescoping joint with a latch assembly in accordance with the invention for use in a conduit such as a production tubing connected to a wellhead for permitting the conduit to be axially displaced in the well bore without disconnecting the conduit from the wellhead. The locking telescoping joint, generally indicated by reference numeral 10 , includes a first tubular section 12 and a second tubular section 14 which has a larger diameter than the first tubular section. The first tubular section 12 has a first end 16 , a second end 18 and a polished outer surface 20 which extends between the first end 16 and the second end 18 . The first end 16 is machined with a standard thread 22 which is compatible with standard tubing connectors. The second end 18 of the first tubular section 12 is provided with a radially projecting latch member that engages a complementary latch point on an inner surface of the second tubular section 14 . The latch member and the latch point may have any configuration that permits selective engagement/disengagement and is adapted to support the weight of a tubing string, as will be described in detail below. In the example shown in FIG. 1, a J-latch type of latch assembly includes a pair of latch pins 24 that cooperate with a plurality of spaced-apart latch points to selectively lock the telescoping joint in one of a plurality of predetermined extensions. The latch pins 24 also prevent the first tubular section 12 from being completely withdrawn from the second tubular section 14 within which it reciprocates. The second tubular section 14 includes a first end 26 and a second end 28 . The first end 26 includes inwardly extending seals 30 which cooperate with the polished outer surface 20 of the first tubular section 12 to provide a fluid seal between the first and second sections. The fluid seals 30 are preferably high pressure fluid seals to ensure that high pressure fluids do not escape from the telescoping joint 10 . The second end 28 of the second tubular section 14 is threaded with an internal thread 32 to enable the connection of a production tubing. As will be well understood, the first end 16 of the first tubular section 12 may have an internal thread and the second end 28 of the second tubular section 14 may have an external thread. It is preferable, however, that the opposite ends of the telescoping joint have compatible but opposite threads as is standard for any production tubing section. A plurality of cooperative latch points are provided on the internal surface 34 of the second tubular section for selectively engaging the latch members on the outer surface 20 of the first tubular section. Two pairs of circumferentially extending slots 36 a , 36 b serve as latch points that receive the latch pins 24 . Axial grooves 68 (see FIGS. 2-5) are provided between the axially spaced-apart latch points 36 a , 36 b for providing a path of travel for the latch pins 24 to permit the first tubular section 21 to travel within the second tubular section 14 . The telescoping joint 10 optionally includes a latch point 38 for the connection of a lift rod (see FIG. 10) which may be used to displace the production tubing string and/or downhole well tools connected to the production tubing string. The latch point 38 may be, for example, an internal thread. While the latch point 38 is shown on an inner surface on the second end 28 of the second tubular section 14 , it may likewise be provided on the second end 18 of the first tubular section if the telescoping joint 10 is oppositely oriented with respect to the wellhead. The orientation of the telescoping joint 10 is a matter of design choice and is only material with respect to the location of the latch point 38 which should be located on the tubular section of the telescoping joint 10 that is remote from the wellhead in order to practice the methods in accordance with the invention, which will be explained below in detail. As will be understood by persons skilled in the art, the lift rod may be latched in the tubing string below the telescoping joint. Circumferential grooves 98 preferably located at opposite ends of the inner surface 34 of the second tubular section 14 permit the second tubular section 14 to be freely rotated with respect to the first tubular section 12 when the telescoping joint is at the limits of its relative travel. This permits the rotary manipulation of downhole components. As will be understood by those skilled in the art, the latch points 70 , 72 (FIG. 4) may likewise be shaped to permit rotation within any arc up to and including 360°. FIGS. 2 to 5 show variations and details of the J-latch type of latch assembly illustrated in FIG. 1 . The slots 36 a , 36 b are machined in the inner surface of the second tubular section 14 , indicated by reference numeral 64 a,b . Accordingly, the latch pin is affixed to the outer surface of the first tubular section 12 , indicated by reference numerals 66 a,b . The latch points can be formed in many different shapes as seen in FIG. 4 . Generally, the groove 68 has a length equal to the travel of the telescoping joint 10 for providing the travel path for the latch pin 24 . A plurality of latch points 70 extend circumferentially from the axial groove 68 in one direction, or in opposite directions and are axially spaced apart from one another to enable the telescoping joint to be locked at any one of a plurality of predetermined axial extensions. Each of the latch points 70 may have a closed end. The closed end may include an axial recess 72 . The latch pin 24 is either a gudgeon pin or lug and can have practically any shape 24 a - 24 f , as shown in FIG. 5 . The shape of the latch pin 24 is preferably compatible with the shape selected for the latch points 70 , 72 . FIG. 6 shows an alternate latch assembly for the telescoping joint 10 in accordance with another embodiment of the invention. Instead of the latch pins 24 and latch points 36 a , 36 b shown in FIGS. 2-4, the latch assembly shown in FIG. 6 is a collet type latch that includes a collapsible traveling collet 52 connected to a traveling sleeve 40 slidably mounted on the first tubular section 12 , and a collapsible collet 42 mounted to the first tubular section 12 above the second end 18 . A plurality of spaced-apart annular engagement ridges 44 a , 44 b , only two of which are shown, are affixed to the inner surface 34 of the second tubular section 14 . The annular engagement ridges 44 a,b cooperate with the collet latch to lock the telescoping joint at a plurality of predetermined axial extensions. A collet latch 48 affixed to a top end of the traveling sleeve 40 is used to lock the collet 42 in a closed condition which permits the collet 42 to be moved past an annular engagement ridge 44 a,b. The traveling latch 50 includes a plurality of slots (not shown) which permit it to collapse and slip past the annular engagement ridges 44 a,b when it is forced against either side of the ridges with enough force. The force required to move the traveling latch 50 past an annular engagement ridge 44 a,b should be considerably greater than the force required to collapse the collet 42 into the collet latch 48 , or to force the collet 42 past a retainer lip 58 on an inner top surface of the collet latch 48 to free the collet 42 from the collet latch 48 . In operation, in order to shorten the telescoping joint, the first tubular section 12 with the sleeve 40 is able to be freely moved upwardly until the traveling latch 50 on the traveling sleeve 40 contacts an annular retainer ridge 44 b if the collet 42 is locked in the collet latch 48 . When the traveling latch 50 abuts the annular retainer ridge 44 a,b , further movement of the first section 12 of the telescoping joint is inhibited until adequate pressure (e.g. 2,000-3,000 kg) is applied force the traveling latch 50 past the annular retainer ridge. When the upward force is applied (by the lift rod, not shown) the collet 42 is first forced out of the collet latch 48 , as shown in dashed lines in FIG. 7, because the force required to move the collet 42 in and out of the collet latch is much less (e.g. 500-1,000 kg) than the force required to collapse the traveling latch, as described above. With the application of adequate force, the traveling latch is forced past the annular retainer ridge 44 a . As shown in FIG. 7, the collet 42 will stop against the annular retainer ridge 44 a unless it is forced back into the collet latch 48 by downward pressure on the first tubular section 12 . As is well understood in the art, the notches 54 in the collet 42 permit the collet to be collapsed into the collet latch 48 . When the collet 42 is expanded, a top edge 56 of the collet 42 rests against an annular retainer ridge 44 a,b and will support the weight of a tubing string and associated downhole equipment. In order to move the collet latch upwardly past the annular retainer ridge 44 a shown in FIG. 7, downward pressure is first applied using the lift rod (not shown). The applied force is adequate to force the collet 42 into the collet latch 48 , but inadequate to force the traveling latch 50 past the annular retainer ridge 44 b . When the collet 42 is locked in the collet latch 48 , the collet latch can be freely moved past the annular retainer ridge 44 a and the series of steps described above is repeated until the traveling latch is forced past the annular retainer ridge 44 a . This process may be repeated as many times as required, or until the limit of travel is reached. In order to extend the length of the telescoping joint shown in FIGS. 6 and 7, the first tubular section 12 is simply forced downwardly using the lift rod (not shown) until the traveling latch is forced past the desired number of annular retainer ridges 44 a,b , or the end of travel is reached. During the downward movement, the collet 42 remains locked in the collet latch 48 . As will be understood by those skilled in the art, the collet 42 shown in FIGS. 6 and 7 prevents extension of the telescoping joint. It therefore permits tubing strings to be placed in tension to prevent downhole tubing string sag when a reciprocal pump is driven from the surface using a sucker rod string. As is also well understood in the art, it is sometimes desirable to use inexpensive compression packers downhole, especially when a submersible production pump is used. However, even when a compression packer is used, the entire weight of the production tubing string is not permitted to rest on the packer. There is therefore still some tension on the tubing string at the wellhead and the collet shown in FIGS. 6 and 7 can be used to place an appropriate amount of weight on the downhole compression packer (not shown). In another embodiment of the invention shown in FIG. 8, the latch assembly is a threaded collet. The threaded collet includes male threads 74 on the outer surface 20 of the first tubular section 12 at the second end 18 . Elongated slots 76 extend axially from the second end 18 of the first tubular section 12 and are circumferentially spaced apart from one another to provide a radial flexibility for the male threads 74 . A plurality of corresponding female threads 78 , only two of which are shown in FIG. 8, are provided on the inner surface 34 of the second tubular section 14 and are axially spaced-apart to serve as latch points for engaging the male threads 76 . Each of the respective male threads 74 and female threads 78 has an upper side 80 , 82 that is substantially perpendicular to a longitudinal axis of the telescoping joint, so that the upper side 80 of the male threads 74 mesh with the upper side 82 of the female threads 78 . Thus, the male threads 74 cannot ratchet upwardly past the female threads 78 . On the other hand, the male threads can be forced down past the female threads 78 because the mating lower sides of the male and female threads are angularly oriented with respect to the axis of the telescoping joints. In order to move the first tubular section 12 upwardly with respect to the second tubular section 14 , the first tubular section 12 must be rotated to disengage the threaded connection. After disengagement, the collet is in a collapsed condition and the male threads 74 ride against the inner surface 34 of the second tubular section 14 . The female threads 74 may alternatively have a square or rectangular cross-section. If the male threads 74 have complementary square or rectangular cross-sections, however, the second tubular section must be rotated through each latch point, regardless of the direction of travel. Triangular male threads configured as described above are therefore preferred. The latch assembly shown in FIG. 8 is used to lock the telescoping joint 10 at a predetermined axial extension against a workload in one direction only. However, as described above even if compression packers are used, the full weight of the tubing string is not permitted to rest on the packer. The telescoping joint shown in FIG. 8 is therefore adapted for use in placing a tubing string in either tension or compression. The latch assembly shown in FIG. 8 is used to lock the telescoping joint 10 at a predetermined extension to prevent the telescoping joint from further extension under a workload. If it is desired to use the telescoping joint locked at a predetermined extension against a compression workload, the triangular cross-section of the threads should be oppositely oriented. That is, the perpendicular side 80 of the male threads 74 should be reversed from the orientation shown in FIG. 8 . The female threads 82 are, of course, likewise reversed in their axial orientation. As noted above, the telescoping joint with the latch assembly in accordance with the invention is adapted to perform any function described in the Applicant's U.S. Pat. No. 5,957,198, plus many new applications enabled or facilitated by the ability to lock the telescoping joint at a plurality of predetermined axial extensions. Therefore, the telescoping joint with the latch assembly in accordance with the invention is adapted to be used in any downhole application in which downhole well tools are advantageously axially displaced in the well bore without disconnecting the tubing string from the wellhead, including, for example: displacement of a zone isolating tool in a production zone which produces both oil and water; barefoot completion of a well bore, in which the telescoping joint permits a hydraulic motor driven drill bit attached to the bottom end of the tubing string to complete the drilling of a well bore from the bottom of the casing to a target depth for the completed bore; for logging a producing formation, in which the production tubing string is retracted above the perforated zone so that a logging tool may be lowered to log the production zone; and any downhole manipulation of tubulars or tools connected to tubing strings. FIG. 9 is a cross-sectional view of a telescoping joint 10 with a latch assembly in accordance with the invention being used to tension a production tubing string in a well bore. A long production tubing string tends to sag under its own weight. This is disadvantageous if a surface-driven reciprocating pump is used to recover hydrocarbons from the well, as explained above. Such tubing strings 84 are anchored at their bottom end by an anchor member 86 , such as a packer connected to the bottom of the production tubing string 84 . A top of the production tubing string 84 includes the telescoping joint 10 and is connected to a tubing hanger, not shown, in a wellhead 88 . A lifting mechanism is temporarily installed on the wellhead 88 to enable the telescoping joint 10 to be retracted until the tubing string is under a desired tension to prevent undesirable sag as hydrocarbon is produced from the well. The lift mechanism shown in FIG. 10 is preferably an apparatus for axially displacing a downhole tool or a tubing string in a well bore as described in applicant's co-pending U.S. patent application Ser. No. 08/992,235, the specification of which is incorporated herein by reference. The apparatus 90 is connected to a lift rod string 94 which runs through an annular seal 92 for containing well pressure and down through the wellhead 88 and the telescoping joint 10 to the latch point 38 (see FIG. 1 ). The lift rod string 94 connects to the latch point 38 to permit the production tubing string 84 to be raised or lowered as required when the production tubing string is suspended from the wellhead. When the bottom end of the production tubing string 84 is anchored. by anchor member 86 (a packer, for example) to the casing of the well bore, the retraction of the telescoping joint 10 using the lift rod string 94 will tension the production tubing string 84 . When the production tubing string 84 is tensioned to a desired extent, the telescoping joint 10 is latched to an appropriate latch point, as described above. The telescoping joint used for tensioning a production tubing string advantageously simplifies the conventional method in which a pup joint having a desired length has to be prepared to replace a top production tubing joint. As is well known, it is a time-consuming, expensive and potentially hazardous operation to determine a required length for the pup joint, and to install it. However, with a locking telescoping joint in accordance with the invention, the operation is quickly, easily and inexpensively done without removing the wellhead or danger of working over an open well bore. The locking telescoping joint 10 also permits the tubing string to be re-tensioned without removing the wellhead or killing the well if, over time, the tubing string loses its tension. Another example of a new application for the telescoping joint is the use of the telescoping joint for setting a production tubing string under compression. This is desirable in circumstances when an economical compression packer is used to anchor a bottom of a production tubing string, as is common practice when hydrocarbons are produced using a submersible pump. As described above with reference to FIG. 10, the telescoping joint 10 is included in the top of the production tubing string 84 , which is attached to a Tubing hanger (not shown) in the wellhead 88 . The apparatus 90 is mounted to the wellhead and the lift rod string 94 is connected at the bottom end to the latch point 38 of the locking telescoping joint 10 . The apparatus 90 is operated to set the compression packer 86 and to release a recommended portion of the weight of the tubing string onto the compression packer. When a required portion of the tubing string weight is supported by the compression packer, the locking telescoping joint 10 is locked at an appropriate latch point and the lift rod string is removed. The locking telescoping joint 10 can also be used for other downhole operations which involve the selective repositioning or manipulation of tubing to set packers, plugs, subsurface safety valves or any other tool that includes a slip, collet, threaded or locking key or other locking or engagement device in the tubing string. Using the locking telescoping joint, such operations are quickly and easily accomplished without removing the wellhead or killing the well. Modifications to the preferred embodiments may occur to persons skilled in the art. For example, the telescoping joint 10 could designed to reciprocate under hydraulic pressure in wells having larger diameter casings. The hydraulically-powered cylinder could be equipped with hydraulic lines from the wellhead and be operated to reposition the downhole well tools without any lifting equipment on the surface. Other modifications or variations may also become apparent to those skilled in the art. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.

A locking telescoping joint is for use in a conduit connected to a wellhead, which permits the conduit to be axially displaced to a new position in the well bore without disconnecting the conduit from the wellhead, and secured in the new position. The locking telescoping joint includes two telescopically interconnected tubular sections which are relatively movable between a fully retracted and a fully extended position and can be locked in a desired position. In contrast with telescoping joints without the locking function which is useful to axially display downhole tools attached to the bottom end of the conduit. The locking telescoping joint enables the use of the telescoping joint to be extended into new applications, such as placing and maintaining a tubing string in tension or compression. The use of the locking telescoping joint reduces the time and cost of many well completion and maintenance operations and thereby reduces the cost of producing hydrocarbons.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION In a conventional coring operation a certain amount of core material is usually lost, thus making it difficult to correlate the remaining material with the well logs to identify the original depth or position of the core sample. The information provided by laboratory core analysis is of reduced value when the particular sample cannot be properly correlated with the other information about the borehole. Therefore, it is an object of the present invention to provide a method of correlating a core sample with its original position in a borehole. SUMMARY OF THE INVENTION In accordance with the present invention there is provided a method of correlating a core sample with its original position in a borehole. The borehole is logged to determine the bulk density of the formation surrounding the borehole. The core sample is scanned with a computerized axial tomographic scanner, hereinafter referred to as "CAT," to determine the attenuation coefficients at a plurality of points in a plurality of cross sections along the core sample. The bulk density log is then compared with the attenuation coefficients to determine the position to which the core sample correlates in the borehole. In addition, the present invention provides a method of correlating a core sample with its original position in a borehole in which the borehole is logged to determine the photoelectric absorption of the formation surrounding the borehole. The core sample is scanned with a CAT at first and second energies to determine the attenuation coefficients for a plurality of points in a plurality of cross sections along the core sample at the first and second energies. These attenuation coefficients are used to determine the effective atomic numbers for the plurality of cross sections along the core. The photoelectric absorption log is compared with the effective atomic numbers that have been determined to determine the position to which the core sample correlates in the borehole. The data obtained with the CAT is on a small length scale, such as millimeters; it is processed to match the larger length scale, which is generally feet, obtained with the logging tools. The CAT images can be correlated with either a bulk density log or a photoelectric log. The correlation with the bulk density log is direct since both measure the amount of Compton scattering which is proportional to the bulk density. In order to correlate CAT scans with the photoelectric log, CAT scans are performed at two different X-ray tube energies. One scan is performed at an energy that is low enough to be predominantly in the photoelectric region, that is, less than approximately 80 keV mean energy, and the other scan is performed at an energy that is high enough to be predominantly in the Compton region, that is, greater than approximately 80 keV mean energy. Either pre-imaging or post-imaging techniques can be applied to the attenuation coefficients obtained by the dual energy scans to determine the effective atomic number of the core sample. Other objectives, advantages and applications of the present invention will be made apparent by the following detailed description of the preferred embodiments of the present invention. Brief Description of the Drawings FIG. 1 is a block diagram of the computerized axial tomographic analyzer utilized in the method of the present invention. FIG. 2 is a side view of the sample holding apparatus employed with the computerized axial tomographic analyzer. FIG. 3 is a cross sectional view taken along lines 3--3 of FIG. 2. FIG. 4 is a top view of the motorized side of the sample holding apparatus. FIG. 5 is a cross sectional view taken along lines 5--5 of FIG. 2. FIG. 6 is a side view of the tube and cylinder portion of the sample holding apparatus. FIG. 7 illustrates a calibration phantom for use with the preferred method of correlating the core sample with the photoelectric log. FIG. 8 illustrates a calibration phantom for use with the preferred method of correlating the core sample with the photoelectric log. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a typical CAT employs an X-ray source 10 to provide X-rays which are indicated by a plurality of arrows; these X-rays are collimated by collimator 12 prior to passing through core sample 14. After the X-rays have passed through core sample 14, they are filtered by filter 16 which can be, for example, air, tungsten or copper. Alternatively, filter 16 can be applied to the X-rays prior to their entering core sample 14 rather than after their passage through core sample 14. The filtered X-rays are then detected by X-ray detectors 18 which generate signals indicative thereof; these signals are provided to suitable data processing and recording equipment 20. The entire operation, from the generation of the X-rays to the processing of the data is under the control of system controller 22. Suitable signals are provided by system controller 22 to voltage controller 24 which controls the voltage applied to X-ray source 10, thereby controlling the energy range of the X-rays. Alternatively, filter 16 can be used to vary the energy range as is known in the art. System controller 22 also provides suitable control signals to filter controller 26 to apply to appropriate filter to the X-rays which have passed through core sample 14 before they are detected by X-ray detector 18. The point along core sample 14 that is being analyzed is detected by sample position sensor 28 which provides signals indicative thereof to sample position controller 30. System controller 22 provides signals which are indicative of the desired point along core sample 14 or the amount of advancement from the last point analyzed, to sample position controller 30, which moves core sample 14 to the proper location. Referring now to FIGS. 2-6, a suitable CAT and sample positioning system for use in the present invention is shown in detail. A typical CAT, for example, the Deltascan-100 manufactured by Technicare Corporation of Cleveland, Ohio is indicated by numeral 34. CAT 34 has a gantry 36 which contains X-ray source 10, collimator 12, filter 16 and X-ray detectors 18. Support structures or tables 38 and 40 are located on opposite sides of CAT 34 and have legs 42 which are suitably attached to, for example, the floor, to ensure that tables 38 and 40 maintain proper positioning and alignment with CAT 34. Tables 38 and 40 each have a set of guide means or rails 44, such as one inch diameter solid 60 case shafts mounted on shaft supports, Model No. SR-16, both being manufactured by Thomson Industries, Inc. of Manhasset, N.Y., on which the legs 46 of trolleys 48 and 50 ride. Preferably, legs 46 have a contact portion 47 that includes ball bearings in a nylon enclosure such as the Ball Bushing Pillow Block, Model No. PBO-16-OPN, which are also manufactured by Thomson. Trolleys 48 and 50 have a flat member 52 which is attached to legs 46 such that member 52 is parallel to rails 44. A member 54 which can consist of two pieces fastened together by suitable means, such as screws, is mounted on member 52 and has an aperture suitable for holding tube 56. Member 52 of trolley 48 has a member 58 attached to the bottom portion of member 52 that is provided with suitable screw threads for mating with gear or screw 60. Screw 60 is driven by motor 62 for moving trolley 48 horizontally. Screw 60 can be, for example, a preloaded ball bearing screw, Model No. R-0705-72-F-W, manufactured by Warner Electric Brake & Clutch Company of Beloit, Wis., and motor 62 can be, for example, a DC motor, Model No. 1165-01DCMO/E1000MB/X2, marketed by Aerotech, Inc. of Pittsburgh, Pa. Motor 62 turns a predetermined number of degrees of revolution in response to a signal from sample position controller 30 of FIG. 1, which can be, for example, a Unidex Drive, Model No. SA/SL/C/W/6020/DC-O/F/BR/R*, which is also marketed by Aerotech. Table 38 and trolley 48 also contain an optical encoding position sensing system, for example, the Acu-Rite-II manufactured by Bausch and Lomb Company of Rochester, N.Y. which comprises a fixed ruler or scale 64 attached to table 38 and an eye or sensor 66 attached to member 52 of trolley 48 for determining the position along ruler 64 at which trolley 48 is located. The digital output from optical sensor 66 is provided to sample position controller 30 of FIG. 1 so that sample position controller 30 can compare this with the desired position indicated by the digital signal from system controller 22 and provide appropriate control signals to motor 62 for rotation of screw 60 to accurately position trolley 48. Table 38 can also be provided with limit switches 68 which provide appropriate control signals to sample position controller 30 which limits the length of travel of trolley 48 from hitting stops 69 on table 38. Tube 56 is centered in the X-ray field 70 of CAT 34. The attachment of tube 56 to members 54 of trolley 48 and 50 by a screw or other suitable fastening means causes trolley 50 to move when trolley 48 is moved by means of screw 60 and motor 62. Tube 56 which preferably is made of material that is optically transparent and mechanically strong and has a low X-ray absorption, for example, Plexiglas, has a removable window 72 to facilitate the positioning of sample holder 74 in tube 56. A core sample 75 is positioned in sample holder 74 as indicated by dotted lines. The ends of sample holder 74 are positioned in central apertures of discs 76, which can be made of a low friction material, for example, nylon, and are sized such that they make a close sliding fit to ensure centering of the sample inside tube 56. Discs 76 are locked in position in tube 56 by screws 78 which can be made of, for example, nylon. In addition, discs 76 can be provided with a plurality of apertures 80 sized to accommodate fluid lines and electrical power lines from various equipment associated with sample holder 74. Sample holder 74 can be a pressure-preserving, core-sample container used in normal coring operations; however, if standard X-ray energy associated with CAT scan analytic equipment, such as the Deltascan-100 mentioned hereinabove, the pressure vessel must be made of material that will allow the X-rays to pass through the container walls, for example aluminum, beryllium or alumina. Aluminum is preferred because it absorbs a portion of the low energy spectra, thus making the beam more monochromatic. Nevertheless, steel pressure containers can be employed if higher energy X-ray tubes or radioactive sources are used. Alternatively, sample holder 74 can be replaced by any unpressurized or unsealed container which is suitable for holding a core sample or other material in a fixed position. In the case of a frozen core sample the container can be positioned inside an insulating cylinder which can be made of, for example, styrofoam or other insulating materials with low X-ray absorption. This insulating cylinder can be filled with dry ice or the like to keep the core sample frozen. If it is desired to heat a core sample, a heating element which has a low X-ray absorption, such as the heating foil manufactured by Minco Products, Inc, of Minneapolis, Minn., can be wrapped around the container to heat the sample and a similar insulating cylinder can be used. Referring to the block diagram of FIG. 1, system controller 22 provides suitable signals to sample position controller 30 to advance core sample 14 a predetermined amount. At each of these locations a plurality of X-ray scans are taken as is known in the art of CAT scan analysis and X-ray detectors 18 provide signals indicative of the X-rays sensed to data processing and recording equipment 20. In addition, the log data obtained from the borehole along with the response function of the logging tool used to obtain such information is provided to data processing and recording equipment 20. In the case of the bulk density log a logging tool, such as the FDC-formation density compensated logging tool of Schlumberger Limited, New York, N.Y., can be used, The linear attenuation coefficients obtained from the CAT scan are directly proportional to the density values of the core. These density values which are determined for a plurality of points in a plurality of cross sections along the core by the CAT are averaged in each cross section. An interpolation of density values is then made between consecutive locations, x i . The interpolated density values, f(x), are then convolved with the response function of the tool, R(x), to obtain the convolved density value, F(x), as indicated by equation (1): ##EQU1## The response function for the tool used in the logging of the borehole can be, for example, ##EQU2## where 1/L box L (x) is the normalized box function of width L and σ is the standard deviation of the Gaussian. The convolved density values, F(x), are then cross correlated with the log density values, G(x), to obtain the maximum of the cross correlation function, φ FG (d), as indicated in equation (3): ##EQU3## The value of d at which φ FG is a maximum is the correlation depth. In the case of a photoelectric log a logging tool, such as the LDT-lithodensity logging tool of Schlumberger Limited, New York, N.Y., can be used. CAT scans are performed at two different X-ray tube energies. One scan is performed at an energy that is low enough to be predominantly in the photoelectric region, that is, less than approximately 80 keV mean energy, and the other scan is performed at an energy that is high enough to be predominantly in the Compton region, that is, greater than approximately 80 keV mean energy. Either pre-imaging or post -imaging techniques can be applied to the attenuation coefficients obtained by the dual energy scans to determine the effective atomic number of the core sample. For example, the techniques of Alvarez et al, U.S. Pat. No. 4,029,963, can be used to determine the effective atomic numbers for the plurality of points in each cross section. Preferably, the effective atomic numbers are determined according to the method described hereinbelow. The energy dependence of the X-ray linear attenuation coefficient μ is separated into two parts: μ=μ.sub.p +μ.sub.c (4) where μ c is the Klein-Nishina function for Compton scattering multiplied by electron density, and μ p represents photoelectric absorption (including coherent scattering and binding energy corrections). The photoelectric and Compton contributions are expressed in the form: μ=aZ.sup.m ρ+bρ (5) where Z is the atomic number, m is a constant in the range of 3.0 to 4.0, ρ is the electron density, and a and b are energy-dependent coefficients. It should be noted that the specific choice of m depends upon the atomic numbers included in the regression of the photoelectric coefficients. Equation (5) depends on the fact that the energy dependence of the photoelectric cross section is the same for all elements. Hydrogen is an exception, but it has negligible contribution to the effective atomic number. For a single element, Z in equation (5) is the actual atomic number. For a mixture containing several elements, the effective atomic number Z* is defined as: ##EQU4## where f i is the fraction of electrons on the i th element of atomic number Z i , relative to the total number of electrons in the mixture, that is, ##EQU5## where n i is the number of moles of element i. The method consists of utilizing a CAT to image a core sample at a high and low X-ray energy level. The energies are chosen to maximize the difference in photoelectric and Compton contributions while still allowing sufficient photon flux to obtain good image quality at the lower X-ray energy. Letting 1 and 2 denote the high and low energy images and dividing equation (5) by ρ, the following relationships are obtained μ.sub.1 /ρ=a.sub.1 Z.sup.3 +b.sub.1 (8a) μ.sub.2 /ρ=a.sub.2 Z.sup.3 +b.sub.2 (8b) Energy coefficients (a 1 , b 1 ) and (a 2 , b 2 ) are determined by linear regression of μ/ρ on Z 3 for the high and low energy images, respectively, of calibration materials with a range of known atomic numbers and densities. Once (a 1 , b 1 ) and (a 2 , b 2 ) are determined, a material of unknown effective atomic number, Z x , can be analyzed in terms of the measured attenuation coefficients μ 1x , μ 2x : ##EQU6## Equations (8a) and (8b) are applied to each corresponding pixel of the high and low energy images; these computations can be performed on a minicomputer or other suitable means. FIG. 7 shows an exemplary phantom 200 used in this method to determine energydependent coefficients a and b. Phantom 200 consists of a housing 202 made of, for example, Plexiglas, which is filled with a liquid 204, for example, water. A number, in this case five, smaller containers or vials 206 are positioned in liquid 204. Each vial 206 is filled with suitable calibration materials for the sample to be analyzed which have known densities and effective atomic numbers. The range of the effective atomic numbers should be chosen to span those of the sample being tested. For example, typical sedimentary rocks have an effective atomic number in the range of 7.5-15.0 and a density in the range of 1.5-3.0 grams per cubic centimeter. FIG. 8 illustrates a preferred embodiment of a phantom for use with this method. Calibration phantom 102 consists of a cylinder 104 which has an aperture 106 that is suitably sized for holding a sample or sample container. Cylinder 104 which can be made of, for example, plexiglas or other suitable material having low X-ray absorption, contains a plurality of vials or rods 108. Vials or rods 108 should contain or be made of material that is expected to be found in the sample under test. The calibration materials in vials or rods 108 have known densities and effective atomic numbers and should be at least as long as the sample under test. In the case of a core sample rods 108 can be made of aluminum, carbon, fused quartz, crystalline quartz, calcium carbonate, magnesium carbonate and iron carbonate. Alternatively, vials 108 could contain the liquid materials contained in vials 206 of FIG. 7. Referring to FIGS. 2-6 and 8, cylinder 104 can be positioned around tube 56 or it can be an integral part of tube 56. Still further, it can be an integral part of sample holder 74 or positioned in some other known relation in X-ray field 70. It should be noted that calibration phantom 102 is scanned at the same time that the sample is scanned. Alternatively, the attenuation coefficients measured for the core sample at the low and high energies can be applied to equation (5), and the low energy equation can be divided by the high energy equation to provide a result that is proportional to the effective atomic number raised to the third power. This result is suitable for correlation with the well logs. The effective atomic numbers for the plurality of points in each cross section are averaged to obtain an average effective atomic number for the cross section. An interpolation of the average effective atomic numbers is then made between consecutive locations, x i . The interpolated effective atomic numbers, f(x), are then convolved with the response function of the tool, R(x), to obtain the convolved effective atomic number F(x), as indicated by equation (1). The response function for the tool used in the logging of the borehole can be, for example, the response functions defined in equations (2a) and (2b). The convolved effective atomic numbers, F(x), are then cross correlated with the photoelectric log values, G(x), to obtain the maximum of the cross correlation function, φ FG (d) as indicated in equation (3). The value of d at which φ FG is a maximum is the correlation depth. The portion of the core sample that has been invaded by the drilling fluid can be omitted from the calculation of the average effective number for a cross section. The amount of invasion can be determined in several ways. For example, an operator can review the effective atomic number image for the plurality of points in each cross section to determine the depth of invasion; the invaded portion of the core can be eliminated from the further calculations by providing suitable entries to the CAT system controller to remove those pixels from further calculations. Alternatively, only a portion of the core sample can be used in the analysis. This can be accomplished by providing suitable instructions to the CAT system controller to include only a predetermined portion of the core in the analysis. For example, the calculations of the average effective atomic number for each cross section can include only the plurality of points that are within a predetermined radius. This radius is chosen to ensure that the fluid invaded portion of the core is not included in the averaging. Still further, the CAT system controller and data processing equipment can implement a system which automatically excludes the portion of the core that has been invaded by the drilling fluid. A center portion of the core is chosen as the reference, for example, the area defined by the radius of the core divided by four. The average effective atomic number for the reference area for each cross section is determined. Then the average effective atomic number for successively larger annular rings for that cross section are determined and compared with the reference. The annular rings can be increased, for example, by the amount of the radius of the core divided by sixteen. When an annular ring has an average effective atomic number that differs from a predetermined amount, for example, five percent, of the average effective atomic number of the reference area of the core, the system stops analyzing the annular rings and eliminates the annular ring which exceeds the predetermined limit and the remainder of the core from any further calculations for that cross section of the core. The average effective atomic number of a respective cross section is then determined by averaging the effective atomic numbers for the portion of the cross section which includes the reference area and all annular rings that do not exceed the predetermined limit. If desired, a material having an effective atomic number that is different than the effective atomic number of the connate fluids in the rock formation surrounding the borehole, for example, barium sulfate, calcium carbonate, sodium tungstate or sodium iodide, can be added to the drilling fluid to enhance the portion of the core that has been invaded. In any of the foregoing methods the mean X-ray energy of the CAT can be chosen to be equal to the mean X-ray energy or energies of the logging tool employed to log the borehole. It is to be understood that variations and modifications of the present invention can be made without departing from the scope of the invention. It is also to be understood that the scope of the invention is not to be interpreted as limited to the specific embodiments disclosed herein, but only in accordance with the appended claims when read in light of the foregoing disclosure.

A method of correlating a core sample with its original position in a borehole. The borehole is logged to determine the bulk density of the formation surrounding the borehole. The core sample is scanned with a computerized axial tomographic scanner (CAT) to determine the attenuation coefficients at a plurality of points in a plurality of cross sections along the core sample. The bulk density log is then compared with the attenuation coefficients to determine the position to which the core sample correlates in the borehole. Alternatively, the borehole can be logged to determine the photoelectric absorption of the formation surrounding the borehole, and this log can be compared with data derived from scanning the core sample with a CAT at two different energy levels.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION [0001] 1). Field of the Invention [0002] This invention relates to exit from and entry to a room via an open window. The window block is a safety security measure. [0003] 2). Background Information [0004] There are occasional news reports of a child exiting via an open window to fall from a dangerous height. There are occasional news reports of foreign entry via an open window with subsequent criminal action against a person within a room. The window block allows limited aperture opening of the window for ventilation while blocking passage of a person. The block also provides for its removal from the inside in a situation of fire impelled quick escape. PRIOR ART [0005] Prior art is plentiful and is such as listed in U.S. Pat. No. 5,552,768 of inventors Mikiel and Usevitch. The Mikiel invention has its friction blocking force generated by a force vector exerted against the window glass, generated by a wedging action. The device has a suction cup for holding the wedge in position on the glass. One version of the present invention petition for letters patent does not place the block on the glass. The block is held by adhesive on the window frame. [0006] Another product on the market also uses a wedge but that product designs around the Mikiel patent. The design around product is a wedge with adhesive and no suction cup. Moreover, the wedge is mounted, not on the glass, but on the frame of the upper sash. That product may be viewed with photograph, description, sale price, and user comments on a web site path defined as follows: “http://www.onestepahead.com//product/85216/127764/117.html”. [0007] The present application for a patent has adhesive but no wedge. The present invention has a sounder but no suction cup. [0008] Prior art also includes U.S. Pat. No. 6,778,086 of title “Open Window Security Lock” by same inventors as petitioners for letters patent herein. In contrast to their patent 086 product defining a shaft, their present product is a small block with its elevation position defined by setting of the upper frame rather than the lower frame patent 086 setting. OBJECT OF INVENTION [0009] It is therefore one object of the present invention to provide a simple, easy to use device that can block a sliding glass window in a partially open position of variable user chosen position. [0010] Another object of the present invention is to provide an easy means for mounting the block in its operating position Another object of the present invention is to add electrical response means to a window block that has been alarm activated by movement of a window sash against the block. [0011] Another object of the present invention is to secure limited opening capability of either the upper sash or lower sash of a double hung window. [0012] Another object of the present invention is to permit a room occupant to quickly remove the window block in event of fire induced emergency exit action. BRIEF DESCRIPTION OF THE INVENTION [0013] A purpose of the present invention is to provide a portable sliding window blocking device that is easy to transport and use. The primary incentive initiating the inventive effort was to protect children from falling out of a window. Also the block offers effective resistance to unlawful entry from the outside. [0014] The block unit may be visualized as an elongated cube shaped box with an adhesive material on one surface (typically double adhesive side tape). The box has a push button switch, a light signaling activation, and a sounder signaling activation. A tool such as a small screw driver blade can be slipped into a small port to switch off the alarm action. [0015] A magnet may be a link in the mechanism for holding the block into its service position. When the protected window is non-magnetic such as wood or aluminum, an intermediary ferromagnetic layer is glued to the window glass or fastened to the frame. The ferromagnetic layer holds the magnet which holds the block. Velcro can work with approximately the same functionality as a magnet in the invention. The magnet fastener sustains shear loading rather than tension loading meaning that the block can be pulled off by tension loading. The block with magnet can not slide off because of a resisting lip on the ferromagnetic layer. Velcro also has pronounced shear resistance because all micro hooks resist shear simultaneously when a Velcro patch is loaded in shear. BRIEF DESCRIPTION OF THE DRAWINGS [0016] FIG. 1 is a full face view of a portable sliding window block according to the invention, viewed from the interior of the room by a viewer looking toward the outside of the window. [0017] FIG. 2 is a full face view of the window block with a push button and sounder shown. [0018] FIG. 3 is a long side view of a window block holding system comprising an adhesive layer and two successive layers, e.g. ferromagnetic sheet and bar magnet. [0019] FIG. 4 portrays the adhesive layer that holds fast to the window frame or glass. [0020] FIG. 5 shows a block bottom view with the alarm switch and adhesive layer. [0021] FIG. 6 portrays an adhesive layer with two successive layers of snapped together Velcro. [0022] FIG. 7 shows an assembled isometric view of an alarm block with switch and sounder. [0023] FIG. 8 is a C-clamp design which attaches not to the sash but is clamped to the track side bar. [0024] FIG. 8 is a block top view showing a wireless door bell button mounted on the block. [0025] FIG. 9 is a block side view and showing how the door bell button is pressed through bending action of a thin metal strip. [0026] FIG. 10 is an end view of an assembly of the block components. DETAILED DESCRIPTION OF THE INVENTION [0027] The original inventive inspiration was to protect young children from open a ventilating window wider than was originally set by the parent and then climbing out. The means to achieve that protection as conceived by the inventor require only three substances, viz.: an adhesive, a cube, and block signal generator. On one surface of a cube is coated the adhesive (double sided sticky tape). On the opposite surface of the cube are displayed a light and a sounder. [0028] In FIG. 1 the part 1 is the block attached with adhesive to the frame of the upper sash. [0029] When the block is mounded on the window upper sash frame the push button switch is pointed downward to intercept any effort to raise the lower sash any further than a few inches. In the event that the upper sash is of moveable design the block is carried down with a lowering sash movement. That restricts and limits the possible distance movement of either or both upper and lower sash; i.e. the mathematical sum of the two opening spaces is a fixed sum [0030] Adhesive such as is found on double sided adhesive tape, holds the block in position on vinyl coated aluminum window frames with very good service quality, and it tenaciously resists removal by hand action. [0031] Wooden window frames of a lesser polish surface may give mixed results. One can add a polished surface plate to the wood. Such a plate can be attached with glue, e.g. epoxy. If the attached plate is steel (ferromagnetic material) the steel provides a convenient mounting and release feature. With the mounting of an intermediate ferromagnetic layer the safety block can be attached to glass, to aluminum, to wood with ease. A sixteenth inch thick or thinner steel plate is adequate for holding fast a bar magnet. Adding a thirty-second inch high curled lip at the force resisting edge guarantees that the magnet can not be displaced in shear direction by an effort to open the window wider. [0032] FIG. 2 shows the total block as piece 1 , the push button electric switch as piece 2 , the sounder as piece 3 , the alarm active light as piece 4 , the reset switch accessible with a small screwdriver blade as piece 5 , the electric battery compartment as piece 6 . [0033] FIG. 3 shows how a bar magnet as piece 9 can hold to ferromagnetic sheet piece 8 which in turn is fastened via adhesive layer piece 7 to any window material such as aluminum, glass, or wood. [0034] FIG. 4 shows the full adhesive layer. [0035] FIG. 5 shows the block bottom with electric push rod switch and adhesive layer piece 7 . [0036] FIG. 6 shows piece 7 adhesive layer, Velcro layer piece 10 and matching Velcro hook layer piece 11 . [0037] Whether FIG. 3 or 4 or 6 is used to hold block piece 1 in service operation will depend upon circumstance. If there is only one window in the room and that window may be required as an emergency fire exit then the magnet or Velcro is the holding means of preference. If the room has several windows capable of being locked then the fire escape passage window should be locked with an easy manual unlock capability and the safety block is placed on another window as ventilation window and without concern as to whether the block can be quickly removed. [0038] FIG. 7 is an isometric view of the block. The part numbers are as defined above. When the block is mounted for service the switch piece 3 points downward to intercept the lower window sash. [0039] FIGS. 8 , 9 , and 10 show how a wireless door bell button is mounted on a window block. [0040] Piece 12 is a screw tapped into a lip structure of piece 13 so as to permit block piece 13 to be clamped to a window frame to intercept a window sash that is being raised a few inches for ventilation. [0041] Piece 14 is a wireless door bell button, commonly available for sale at many hardware stores. The switch button of piece 14 is pushed through the force of an intermediary pin piece 15 . Piece 15 is a six penny nail sawed off at the appropriate length. Piece 16 is a strip of sheet metal of springy quality. The window sash movement bears at the end region of the strip of sheet metal. Thus when the strip is bent upward toward the wireless switch button the switch is closed but the switch can not be crushed through pin 15 movement because the sash intercepts the structure of the block piece 13 . It is only the spring force of piece 16 that is transmitted to pin piece 15 . [0042] The market appeal of the product lies in its simplicity of form and low cost of installation. The appeal is to parents with small children. [0043] The web page cited above (“onestepahead”) lists reader and user comments. One window wedge user complained that his window sash rode right over the wedge without being stopped. One may surmise that the wooden strip on the window frame which defines the track had some missing nails. The strip then bowed out allowing the lower sash to spring over the window block wedge adhesive fastened to the frame of the upper sash. In that situation a wedge is not a preferred design and the present invention would work better. Since the ferromagnetic steel plate glued to the upper window glass would measure less than one eighth thick, one can use the magnet holding system and still remove the block device and its magnet for window washing such as to allow clearance to move either sash over its full normal travel distance. This removable quality of the magnetic would not compromise the protection for a small child who is not likely to be capable of pulling loose a bar magnet. An adult escaping from a room fire can readily lift a bar magnet from its mount. The lip on the ferromagnetic mount plate still provides total shear resistance force. [0044] A few more words about the C-clamp (shown in drawing FIG. 8 ) and wireless features are appropriate. The guiding principle was to minimize custom design features. The creativity lay in joining together an assembly of products already on the market. The rule was not to open equipment boxes to solder wire attachments. Only the simple assembly support was custom made of wood. On that support was mounted a wireless door bell button. The actuator for the button switch was a meritorious design. The window sash should not rigidly press against the door bell button lest it damage the button. A nail head, as a part of a push rod (sawed short 6 penny nail), pushed against the button. However that was a flexible push because the force came through a pliable sheet metal strip bridging between the sash force point (end opposite the fulcrum) and the push rod end. [0045] The wireless receiver sounder operated when the window sash movement closed the wireless door bell button. The next sequence choice was to have a latching relay that would keep a tripped alarm operating until a reset button could be pushed. One could open the wireless receiver box and solder some connector wires. The choice was to simply position a sound operated switch in close proximity to the wireless bell. Now the easy plug-in choices are wide open. A string of blinking Christmas tree lights can be added. A dial out phone system from Radio Shack can be added, An intercom listening system can be added and activated. None of such add devices requires soldering or opening electronic package boxes. Any one, of such devices which are activated by the wireless receiver, is referenced in the claims section as a supplemental alarm responding device. [0046] Many modern windows have mobility only in the lower sash. (Window washing is performed by a mechanism that allows the lower sash to be hinged out of its vertical track.) The single block does the job of limiting travel of the lower sash. [0047] When the invention is installed in a double hung window where both sashes are moveable some mechanism is needed to immobilize the upper wooden sash if the C-clamp design is used. Many of such old windows had counterweights and sash cords. If the intruding person on the outside of the window were to push the top sash down it would still be difficult to climb over the obstacle of the two sashes together. Moreover, there is an easy way to immobilize the upper sash. A wood screw will do the job. A gypsum board dry wall screw was placed at the top of the window between the wooden sash frame and the fixed wooden cross member. [0048] The adhesive block attached to the upper sash would seem to be adequate alone since lowering the upper sash would cause the block to push closed the lower sash. Based upon actual experiments, the adhesive did not hold reliably on old wooden window frames. The wooden C-clamp did work with no problems. An adequately fastened adhesive held block mounted on the upper sash fully protects against excessive opening of either upper or lower sash. [0049] The use of a magnet or Velcro as a part of the holding means inspires a break through to even greater utility. When the battery, which operates the wireless, needs an annual replacement the owner simply disengages the device at the magnet holding point and owner has an environment for easy replacement of the battery. Velcro can do the same job as a magnet, Analysis of the Mechanics of Mounting the Block [0050] Window block prior art shows several stop means, viz.: a suction cup, a double face adhesive tape, a window frame structure integrated latch as possible ways to restrict window opening travel distance. The use of a magnet or Velcro for such a mounting purpose appears to be novel. The primary objective is to implement a holding force. A derivative objective is capability and ease of manipulation, e.g. removal of block to wash a window or removal of a block to replace an exhausted electric battery. Implied is a need for ease of reinstallation and a desired facility of ease of initial installation. [0051] The use of a magnet opens up a variety of holding configurations. The magnetic field strength can be the holding force. The magnetic force may simply serve to position a hook structure such that the greater holding force comes from a mechanical attachment pattern. The magnetic force may serve to supplement a tacky adhesive holding force. The magnetic force may serve to hold a latch mechanism in place while the mounting glue or cement sets up like epoxy cement. Best Version Disclosed of Window Block [0052] The window block process is primarily a resistive force with a secondary value of detection. Let us begin with evaluation of prior art to see whether there are any remaining niche values to be covered. Prior art has covered suction cup and tacky double sided adhesive tape useful for existing windows. Another prior art is a latch stop built into a new window. A screw clamp that holds to the window track edge may be found new and useful. Velcro may be found new and useful. A bar magnet shows evidence of being new and appears to be useful. [0053] A bar magnet can be used on glass by first gluing a thin sheet steel plate to the glass. Enhanced resistance to shear movement can be achieved with a slight lip bend at the edge of the sheet steel. Also bear in mind, when removing the sensor for service, that there is the option of having the magnet permanently attached to one object (the glass) or the other object (the block) or permanently affixed to neither. The sheet steel plate has low profile that permits full movement of either sash when the sensor is removed. [0054] Comparing a magnet with Velcro, they have similarity in installation and function. Both involve a glue bonding detail between the window glass or window frame and the block unit. Velcro has high resistance to shear movement since each thread hook holds mechanically. A magnet resists shear by a force times coefficient of friction factor, but it also has capability of utilizing a restraining lip in the attracted sheet steel plate. A bar magnet does not buckle if loaded in its plane. Velcro fabric holds in shear not by resisting buckling but by hook distribution. [0055] The straight glue layer between block and window structure involves some compromise between glue holding (or tacky tape holding) and easy removal capability. The magnet and Velcro have no such problem [0056] Another contender for the role of holding the block to the window is a screw clamp that grips the window frame. It is a close race with maybe Velcro being the winner of best disclosed design.

A child safety window block consists of a block of material of which one face has a tacky adhesive. The block by the adhesive can be affixed to a window frame to limit the opening travel of the window to a ventilating gap which is too small for a child to pass out of the window. One block variation is a design with a push button switch which activates a sounder and which is reset to off by a concealed switch accessible with a narrow pointed tool. Another design incorporates a radio wireless button. The wireless receiver door bell sounder can activate any of a variety of attached security alarm features. Another variation uses a magnet or Velcro as part of the block fastening mounting.

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF THE INVENTION This invention relates to height safety equipment. More particularly although not exclusively it discloses an improved roof anchor and clamping system for use on timber rafters, trusses or other suitable members. BACKGROUND OF THE INVENTION The need for safety systems for people working at heights has long been recognised. Fall-arrest systems have been devised to protect workers in situations where they would otherwise be exposed to risk of serious injury or death by falling. Fall-arrest systems are a means by which the worker is attached to a secure point on the underlying structure. An integral part of any fall-arrest system is the anchorage point to the underlying structure. Both the anchor point and the underlying structure should be capable of sustaining the forces that may be imposed when arresting a fall with a wide margin of safety. It is essential that the anchor point and its means of attachment to the underlying structure do not interfere with the ability of the underlying structure to carry its load requirements. In the building industry timber roof frames are typically constructed of pre-assembled trusses. In many cases the drilling of holes and placement of bolts in the truss/rafter member may lead to structural weakening and inability of the truss/rafter to carry its load requirements. In particular, the truss/rafter may be unable to sustain the forces imposed in arresting a fall because of such weakening. All of the anchor points designed to date rely on penetration of rafter/truss members or other timber members by nails, screws or bolts through a rigid plate system as an integral means of support. These penetrations and plates may weaken the timber unacceptably. OBJECTS OF THE INVENTION One of the objects of the present invention is to provide an anchor point of attachment to the underlying structure which meets stringent government standards, minimises impact on the underlying structure and maintains a high degree of safety for workers. The unique clamping mechanism of the present invention has several features that enable it to meet this objective. Firstly, the anchor is attached to the rafter/truss member without relying on any strength reducing penetration of the member. Secondly, the load is spread out along the rafter/truss thereby minimising the impact on the underlying member. A second object of the present invention is to provide an anchoring means that can be installed conveniently and quickly in standard roof construction. The anchor may be sized to conform to the dimensions of any timber suitable for framing roofs. In addition the anchor can be attached to a rafter/truss at almost any location on a roof. The user can also install the anchor without special equipment. In addition, the anchor cain be easily removed for re-use. Fall-arrest systems usually include elements that should be replaced or inspected after they have been used to arrest a fall. To minimise the risk of overlooking impairment of the system caused by heavy loading during a fall it is desirable to provide a clear permanent indication that the fall-arrest system has been loaded. Therefore, a third object of the present invention is to provide a clear, permanent indication that the fall-arrest system has been loaded. SUMMARY OF THE INVENTION Accordingly an anchor for securing a working line to a structure is disclosed, said anchor including a sole plate adapted for attachment to said working line, at least one friction plate and a connector means whereby in use of the anchor the sole and friction plates are located against respective opposite sides of a member of said structure and are linked together by said connector means in a manner such that a working line load on the sole plate generates a clamping forces between said sole plate and friction plate which resists movement of the anchor by gripping only the outside of said member without any strength reducing penetration thereof. Preferably the sole plate includes an eye bolt for attachment of the working line. It is further preferred that the eye bolt is of one piece construction. It is further preferred that the eye bolt is adapted for plastic deformation to absorb impact loading and provide visual evidence of said loading. It is further preferred that the friction plate is formed with transverse teeth or grooves to facilitate gripping of the member. BRIEF DESCRIPTION OF THE DRAWINGS The currently preferred embodiments of the invention will now be described with reference to the attached drawings in which:— FIG. 1 is a perspective view of a first embodiment of an anchor according to the invention, FIG. 2 is an exploded view of the anchor of FIG. 1 , FIG. 3 is a perspective view of a second embodiment of an anchor having two friction plates, FIG. 4 is an exploded view of the anchor of FIG. 3 , FIG. 5 is a perspective view of the anchor of FIG. 1 installed on a rafter/truss, FIG. 6 is a perspective view of the anchor of FIG. 3 installed on a rafter/truss, FIG. 7 is a cross-sectional view along the lines A—A of FIG. 5 , FIG. 8 is a schematic perspective view of a building showing the anchors in use, and FIGS. 9 , 10 and 11 show modified versions of the anchor of FIG. 3 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the first embodiment of the invention shown in FIGS. 1 , 2 , 5 and 7 the anchor and clamping system comprise an eyebolt 1 (for attachment of a working or safety line) which is welded into a sole plate 2 that is clamped to the rafter/truss 3 by means of a U strap 4 and friction plate 5 . The U strap is connected to the sole plate by means of a bolt 6 that passes through the U strap and sole plate. The bolt is secured with a nut 7 and washer 8 . The friction plate 5 is connected to the U strap 4 by means of a second bolt 9 that passes through the U strap and the friction plate. This bolt is secured in place with a nut 10 and a washer 11 . The top surface of the friction plate preferably has toothed grooves 12 that contact the underside rafter/truss to prevent movement of the friction plate. A small clout 13 is also preferably passed through the preformed clout aperture 14 in the U strap to assist in locating the anchor in the desired position. FIG. 5 shows the anchor of FIG. 1 fitted to a rafter/truss 3 . To install the anchor the bolt 6 is removed from the sole plate 2 . The U strap 4 with friction plate 5 attached is slid squarely onto the rafter/truss from the underside so that the friction plate abuts the underside thereof. It is important that the toothed grooves of the friction plate be in contact with the underside of the rafter/truss. The sole plate 2 is placed on the upper surface of the rafter/truss so that the arrow 15 is pointing in the direction of intended loading and the bolt hole 16 of the sole plate lines up with the bolt holes 17 of the U strap. The U strap 4 is then connected to the sole plate by passing the bolt 6 through the bolt holes in the U strap and the sole plate and held in place with thee nut and washer. The sole plate is then tapped on the rear surface 18 in order to tension the clamping mechanism of the U strap and friction plate. The locating clout 13 is passed through the aperture in the U strap to assist in locating the U strap and friction plate in the desired position. When loading force is applied to the eyebolt 1 a clamping action is generated between the sole plate 2 and the friction plate 5 . The loading force can the eyebolt pulls the eyebolt and sole plate in the direction of load. The force is also transmitted via the U strap 4 to the friction plate 5 . The force on the friction plate increases the clamping action on the rafter/truss 3 . This clamping action allows both plates to stay parallel with the plane of the rafter/truss and minimises any adverse loads on this member when arresting a fall. The eyebolt 1 is preferably forged out of 316 stainless steel and is of one piece construction. It consists of a ring 19 to which the safety or working line is attached and a rod with a tapered section 20 and a parallel section 21 . Preferably the smaller end of the tapered section is adjacent to the ring. The parallel section of the eyebolt is press fitted into the sole plate and is then plug welded to the arris 22 of the sole plate. In addition, forged into the eyebolt is a raised locating lip 23 to assist in positioning the rubber flashing sheath 24 . Under heavy loads, as when arresting a fall, the rod of the eyebolt will undergo plastic deformation. This plastic deformation is initiated at the eyebolt segment 21 of constant cross-section. This plastic deformation has two purposes. Firstly it provided a clear visual indication that the system has been significantly loaded, thus indicating that part or all of the system may need replacing prior to further use. Secondly the plastic deformation will contribute to shock absorption at high loads. A number of the dimensions are variable to suit different applications of the anchor. The dimensions of the sole plate, U strap and friction plate can be varied to suit rafters/trusses of varying size. In addition the length of the parallel section of the eyebolt can be varied to cater for differing roof coverings. Such variations may be necessary if the eyebolt is to be used after batons and tiles have been placed above the rafter/truss. FIG. 7 shows the anchor of FIG. 1 , fitted to a rafter/truss 25 that has batons 26 and tiles 27 in place. The parallel segment 21 of the eyebolt has been extended so that the ring 19 projects well clear of the tiles. The rubber flashing sheath 24 is shown in position around the locating lip 23 of the eyebolt and is sealed to the tiles. This sheath provides a weather seal and prevents water damage to the rafter/truss. It is intended that the anchor of FIG. 1 be for temporary use. The second embodiment of the invention as shown in FIGS. 3 , 4 and 6 is intended for bi-directional use and may be permanently installed on a roof. This version has a dual clamping action allowing loading in either direction. The sole plate 28 is extended in length and a pair of U straps 29 , 30 and friction plates 31 , 32 are attached. These U-straps and friction plates are similar to the U strap and friction plate described earlier with the first embodiment. FIG. 6 shows the second embodiment installed on a rafter/truss 33 . To install this anchor the two bolts 34 . 35 connecting the U straps to the sole plate are removed. The sole plate is then positioned on the rafter/truss in the desired location. The U-strap 29 with friction plate 31 attached is then slid squarely onto the rafter/truss from the underside so that the friction plate 31 abuts the under surface of the rafter/truss. The U strap 29 is positioned so that the bolt holes 36 in the U-strap line up with the bolt hole 37 in the sole plate. The U-strap is then connected to the sole plate by passing the bolt 34 through the U-strap and the sole plate and securing it with the nut 38 and washer 39 . The sole plate is then tapped on the rear surface 40 in order to tension the clamping mechanism of the U-strap and friction plate. A small locating clout 41 is passed through the aperture 42 in the U-strap to assist in locating the U-strap and friction plate in the desired position. The second U-strap 30 and friction plate 32 is then slid squarely onto the rafter/truss from the underside so that the friction plate 32 abuts the under-surface of the rafter/truss. This second U-strap 30 is positioned so that the bolt holes 43 in the U-strap line up with the bolt hole 44 in the sole plate. The U-strap 30 is then connected to the sole plate by passing the bolt 35 through the U-strap and sole plate and securing it in place with the nut 45 and washer 46 . To tension the clamping mechanism of the second U-strap it is necessary to separate the two friction plates 31 , 32 . This is achieved by tapping on the front surface 47 of the second friction plate 32 to push it away from the first friction plate 31 . A small locating clout 48 is passed through the aperture 49 in the U-strap to assist in locating the second U-strap and friction plate in the desired position. Loading the eyebolt 50 in either direction as indicated by the directional arrows 51 , 52 on the sole plate will tension the clamping mechanism of the appropriate U-strap and friction plate in a manner identical to the first embodiment. FIG. 8 is a schematic perspective view showing anchors according to the first and second embodiments of this invention in use on a building roof. The first embodiment is the single action clamping system 53 . The worker attached his working line 54 to this anchor. It is preferred that workers always have a second safety line 55 connected to a second anchor point. This second line has two purposes. Firstly it provides a back up in the event of failure of any component of the working line and secondly it reduces the pendulum effect in the event of a fall. The second embodiment is the dual action clamping system 56 that can be used bi-directionally. This anchor can be installed on one face of the roof and enable the worker to work either face of the roof. The worker may climb onto the roof by means of a ladder. The ladder is attached by a working line 57 to a dual action anchor that is fixed to the roof. A cable or rope may be connected to two dual action anchors 56 to provide a point of attachment for a worker's safety line. The worker may attach himself to the cable and move up the roof using a shunt or similar mechanism. With structures having exposed interior roof beams a variation of the dual action anchor is shown in FIGS. 9 and 10 . This anchor is primarily intended for permanent installation. The friction plate in this case comprises a pair of friction U straps 58 , 59 located under the beam 60 . These are hingedly connected to the sole plate 61 by pivot straps 62 , 63 , 64 and 65 on each side and bolts 66 , 67 . The bolts pass transversely through the lower portion of the beam and thus are not visible from the underside. The structure and operation of this version is basically the same as that described earlier with reference to FIGS. 3 and 6 . When a loading force is applied to the eyebolt 68 it is pulled in the direction of the load and a clamping force is generated between the sole plate and the friction U straps by means of force transmission through the pivot straps. Although not shown small locating clouts may also be driven upward through apertures 70 the friction U straps and into the underside of the beam. While the bolts 66 , 67 extend through the width of the beam 60 this is not to be considered a strength reducing penetration as the load is still applied to the beam by means of compression between the sole plate and friction U straps. No significant force is applied by the bolts directly to those immediately surrounding beam fibres. The version of the anchor shown in FIG. 11 operates in a similar manner to that of FIG. 3 and the main components corresponding in function are indicated by the same numbers which however are primed. (′) to distinguish them. In this case the sole plate 28 ′ has cutouts 71 at each end so as to fit different widths of rafter. Although the invention is not limited to any specific dimensions, these widths may for example be 35 mm and 50 mm as commonly used in construction. Separate sets of friction plates of different breadths together with corresponding U straps would also be provided. In FIG. 11 the anchor is shown fitted to a larger sized rafter 72 , using a wide set of U straps 30 ′, 31 ′ and friction plates 31 ′, 32 ′. However, by bolting as second narrower set of U straps and friction plates (not shown) to the sole plate using apertures 73 , 74 in each cutout portion the anchor may be fitted to a smaller sized rafter. It will thus be appreciated that this invention at least in the form of the embodiments described provides a novel and improved roof anchor for fall-arrest. Clearly however the examples disclosed are only the currently preferred form of the invention and a wide variety of modifications may be made which would be apparent to a person skilled in the art. For example the shape and configuration of the sole and friction plates and connecting straps may be changed according to application or design preference. For example with those installations requiring placement of the anchor along the apex of the roof the sole plate may be altered to a V or any other suitable configuration. Also, while the embodiments described are preferably constructed from high strength steel the invention extends to the use of other suitable materials.

There is an anchor for securing a working line ( 54 ) to a structure. The anchor includes a sole plate ( 2 ) with an attachment ( 19 ) for the working line ( 54 ). There is at least one friction plate ( 5 ) and a connector strap ( 4 ). In use of the anchor the sole plate ( 2 ) and friction plate ( 5 ) are located against respective opposite sides of a rafter ( 3 ) of the structure and are linked together by the strap ( 4 ) in a manner such that the working line load on the sole plate ( 2 ) generates a clamping force between the sole plate ( 2 ) and the friction plate ( 5 ). This force resists movement of the anchor by gripping only the outside of the rafter ( 3 ).

You are an expert at summarizing long articles. Proceed to summarize the following text: FIELD OF DISCLOSURE [0001] The current invention includes an apparatus and a method for creating a pulse within drilling fluid, generally known as drilling mud that is generated by selectively initiating flow driven bi-directional pulses. Features of the device include operating a flow throttling device (FTD) within a specially designed annular flow channel that reduces turbulent flow of the drilling fluid in a measurement-while-drilling device to provide for reproducible pressure pulses that are translated into low noise signals. The pulse is then received “up hole” as a series of signals that represent pressure variations which may be interpreted as gamma ray counts per second, azimuth, etc. by oilfield engineers and managers and utilized to increase yield in oilfield operations. BACKGROUND [0002] Current pulser technology includes pulsers that are sensitive to different fluid pump down hole pressures, and flow rates, and require field adjustments to pulse properly so that meaningful signals from these pulses can be received and interpreted uphole. [0003] One of the advantages of the present disclosure is that the embodiments are that it decreases sensitivity to fluid flow rate or pressure within limits, does not require field adjustment, and is capable of creating recognizable, repeatable, reproducible, clean (i.e. noise free) fluid pulse signals using minimum power due to a unique flow throttling device (FTD) magneto-electric and turbine generated energy, and pilot flow channel design thereby helping to reduce MWD preparation for MWD drilling, a MWD field engineer at the well site continuously, and expenses associated with downtime. The annular flow channel is specifically designed such that primarily laminar flow exists in the area where the pulse occurs, acted upon by a flow throttling device thereby providing frequent essentially noise-free pulses and subsequent noise-free signals. Additional pulsers with varying pressure amplitudes and/or frequencies are easily added to enable an exponential increase in the bit rate that is sent uphole. This will also allow the addition of more downhole sensors without losing formation resolution. DESCRIPTION OF PRIOR ART [0004] The present invention discloses a novel device for creating pulses in drilling fluid media flowing through a drill string. Devices currently in use require springs or solenoids to assist in creating pulses and are primarily located in the main drilling fluid flow channel. Current devices also require onsite adjustment of the flow throttling device (FTD) pulser according to the flow volume and fluid pressure and require higher energy consumption due to resistance of the fluid flow as it flows through an opened and throttled position in the drill collar. [0005] The present inventive apparatus and assembly is also supported by a rigid centralizer centralized within the fluid flow. The centralizer provides centralization, support and shock dampening for the assembly. The pulser assembly includes a fishing head and fluid screen assembly attachment at the top end facing the flow. [0006] The device provided by the current invention allows for the use of a flow throttling device that moves from an initial position to an intermediate and final position in both the upward and downward direction corresponding to the direction of the fluid flow. The present invention avoids the use of springs, the use of which are described in the following patents which are also herewith incorporated by reference in U.S. Pat. No. 3,958,217, U.S. Pat. No. 4,901,290, and U.S. Pat. No. 5,040,155. [0007] U.S. Pat. No. 5,040,155 to Feld, et. al. describe a double guided fluid pulse valve that is placed within a tube casing making the valve independent of movement of the main valve body and free of fluctuations of the main valve body. The valve contains a pressure chamber with upwardly angled passages for fluid flow between the pressure chamber and the main valve body. Double guides ensure valve reliability in the horizontal position. [0008] U.S. Pat. No. 5,473,579 to Jeter, et. al., describes a pulser that utilizes a servo valve and spring acting upon each other to urge a signal valve to move axially within a bore with signal assistance coming from a counter balance compensator device. [0009] U.S. Pat. No. 5,117,398 to Jeter describes a pulser device that uses electromagnetically opened latches that mechanically hold the valve in the closed or open position, not allowing movement, until a signal is received and the latches are electronically released. [0010] U.S. Pat. No. 6,002,643 by Tchakarov, et al., describes a pulser device in which a bi-directional solenoid contains a first and second coil and a rod extending within the coils used to actuate a poppet valve creating bi-directional pressure pulses. Orifices to permit the flow of drilling fluid to be acted upon by the piston assembly within the main body of the pulser tool and a pressure actuated switch to enable the electronics of the control device to act upon the pulser tool. [0011] U.S. Pat. No. 4,742,498 to Barron describes a pulser device that has the piston that is acted upon by the drilling fluid and is allowed seating and unseating movement by use of springs and an omni directional solenoid. [0012] U.S. Pat. No. 6,016,288 to Frith discloses a servo driven pulser which actuates a screw shaft which turns and provides linear motion of the valve assembly. All components except the shaft are within a sealed compartment and do not come in contact with the drilling fluid. [0013] U.S. Pat. No. 5,802,011 to Winters, et al., that describes a solenoid driven device that pivots a valve that enters and leaves the annular drilling fluid flow blocking and unblocking the fluid flow intermittently. [0014] U.S. Pat. No. 5,103,430 to Jeter, et al., describes a two chamber pulse generating device that creates fluid chambers above and below a poppet valve that is servo driven. Pressure differential is detected on either side of the poppet through a third chamber and the servo is urged to move the poppet in order to stabilize the pressure differential. [0015] U.S. Pat. No. 5,901,113 to Masak, et al., describes a measurement while drilling tool that utilizes inverse seismic profiling for identifying geologic formations. A seismic signal generator is placed near the drill bit and the generated known signals are acted upon by the geologic formations and then read by a receiver array. [0016] U.S. Pat. No. 6,583,621 B2 to Prammer, et al., describes a magnetic resonance imaging device comprising of a permanent magnet set within a drill string that generates a magnetic flux to a sending antennae that is interpreted up hole. [0017] U.S. Pat. No. 5,517,464 to Lerner, et al., describes a pulse generating device utilizing a flow driven turbine and modulator rotor that when rotated creates pressure pulses. [0018] U.S. Pat. No. 5,467,832 to Orban, et al., describes a method for generating directional downhole electromagnetic or sonic vibrations that can be read up hole utilizing generated pressure pulses. [0019] U.S. Pat. No. 5,461,230 to Winemiller, describes a method and apparatus for providing temperature compensation in gamma radiation detectors in measurement while drilling devices. [0020] U.S. Pat. No. 5,402,068 to Meador, et. al., describes a signal generating device that is successively energized to generate a known electromagnetic signal which is acted upon by the surrounding environment. Changes to the known signal are interpreted as geological information and acted upon accordingly. [0021] U.S. Pat. No. 5,250,806 to Rhein-Knudsen, et al., describes a device wherein the gamma radiation detectors are placed on the outside of the MWD device to physically locate them nearer to the drill collar in order to minimize signal distortion. [0022] U.S. Pat. No. 5,804,820 to Evans, et al., describes a high energy neutron accelerator used to irradiate surrounding formations that can be read by gamma radiation detectors and processed through various statistical methods for interpretation. [0023] U.S. Pat. No. 6,057,784 to Schaaf, et al., describes a measurement while drilling module that can be placed between the drill motor and the drill bit situating the device closer to the drill bit to provide more accurate geological information. [0024] U.S. Pat. No. 6,220,371 B1 to Sharma, et al., describes a downhole sensor array that systematically samples material (fluid) in the drill collar and stores the information electronically for later retrieval and interpretation. This information may be transmitted in real time via telemetry or other means of communication. [0025] U.S. Pat. No. 6,300,624 B1 to Yoo, et al., describes a stationary detection tool that provides azimuth data, via radiation detection, regarding the location of the tool. [0026] U.S. Pat. No. 5,134,285 to Perry, et al., describes a measurement while drilling tool that incorporates specific longitudinally aligned gamma ray detectors and a gamma ray source. [0027] U.S. Application No. 2004/0089475 A1 to Kruspe, et. al., describes a measurement while drilling device that is hollow in the center allowing for the drilling shaft to rotate within while being secured to the drill collar. The decoupling of the device from the drill shaft provides for a minimal vibration location for improved sensing. [0028] U.S. Pat. No. 6,714,138 B1 to Turner, et. al., describes a pulse generating device which incorporates the use of rotor vanes sequentially moved so that the flow of the drilling fluid is restricted so as to generate pressure pulses of known amplitude and duration. [0029] G.B. Application No. 2157345 A to Scott, describes a mud pulse telemetry tool which utilizes a solenoid to reciprocally move a needle valve to restrict the flow of drilling fluid in a drill collar generating a pressure pulse. [0030] International Application Number WO 2004/044369 A2 to Chemali, et. al., describes a method of determining the presence of oil and water in various concentrations and adjusting drilling direction to constantly maintain the desired oil and water content in the drill string by use of measuring fluid pressure. The fluid pressure baseline is established and the desired pressure value is calculated, measured and monitored. [0031] International Publication Number WO 00/57211 to Schultz, et. al., describes a gamma ray detection method incorporating the use of four gamma ray sondes to detect gamma rays from four distinct areas surrounding a bore hole. [0032] European Patent Application Publication Number 0 681 090 A2 to Lerner, et. al., describes a turbine and rotor capable of restricting and unrestricting the fluid flow in a bore hole thereby generating pressure pulses. [0033] European Patent Specification Publication Number EP 0 781 422 B1 to Loomis, et. al. describes utilizing a three neutron accelerator and three detectors sensitive to specific elements and recording device to capture the information from the three detectors. SUMMARY [0034] The present disclosure involves the placement of a Measurement-While-Drilling (MWD) pulser device including a flow throttling device located within a drill collar in a wellbore incorporating drilling fluids for directional and intelligent drilling. [0035] The present disclosure will now be described in greater detail and with reference to the accompanying drawing. With reference now to FIG. 1 , the device illustrated produces pressure pulses in drilling fluid flowing through a tubular drill collar and an upper annular drill collar flow channel. The flow guide is secured to the inner diameter of the drill collar. The centralizer secures the lower portion of the pulse generating device and is comprised of a non-magnetic, rigid, wear resistant material with outer flow channels. [0036] Specifically, the pulser assembly provides essentially four outer flow channels that allow fluid, such as drilling mud, to flow. These are defined as the upper annular, the middle annular, lower annular, and centralizer annular collar flow channels. The inner lower and inner middle flow channels direct the drilling mud flow to the pulser assembly within the MWD device. Annular flow of the drilling fluid, by the flow guide and flow throttling device, is essentially laminar, and pulse signals are generated that are more detectable. Incorporation of a method and system of magnetic coupling, a concentrically located turbine, inductive coil for electrical power generation, bellows design and reduced pressure differential, collectively significantly reduce battery energy consumption when compared with conventional devices. [0037] In a preferred embodiment, the MWD device utilizes a turbine residing near and within the proximity of a flow diverter. The flow diverter diverts drilling mud in an annular flow channel into and away from the turbine blades such that the force of the drilling mud causes the turbine blades and turbine to rotationally spin around an induction coil. The induction coil generates electrical power for operating the motor and other instrumentation mentioned previously. The motor is connected to the pilot actuator assembly via a drive shaft. The pilot actuator assembly comprises a magnetic coupling and pilot assembly. The magnetic coupling comprises outer magnets placed in direct relation to inner magnets located within the magnetic pressure cup or magnetic coupling bulkhead. The magnetic coupling translates the rotational motion of the motor, via the outer magnets to linear motion of the inner magnets via magnetic polar interaction. The linear motion of the inner magnets moves the pilot assembly, comprising the pilot shaft, and pilot valve, linearly moving the pilot into the pilot seat. This action allows for closing the pilot seat, pressurizing the flow throttling device, closing the flow throttling device orifice, thereby generating a pressure pulse. Further rotation of the motor, drive shaft, via the magnetic coupling, moves the pilot assembly and pilot away from the pilot seat, depressurizing the flow throttling device sliding pressure chamber and opening the flow throttling device and completing the pressure pulse. Identical operation of the pilot into and out of the pilot seat orifice can also be accomplished via linear to linear and also rotation to rotation motions of the outer magnets in relation to the inner magnets such that, for example, rotating the outer magnet to rotate the inner magnet to rotate a (rotating) pilot valve causing changes in the pilot pressure, thereby pushing the FTD (flow throttling device) up or down. [0038] Unique features of the pulser include the combination of middle and lower inner flow channels, flow throttling device, bellows, and upper and lower flow connecting channels possessing angled outlet openings that helps create signals transitioning from both the sealed (closed) and unsealed (open) positions. Additional unique features include a flow guide for transitional flow and a sliding pressure chamber designed to allow for generation of the pressure pulses. The flow throttling device slides axially on a pulser guide pole being pushed by the pressure generated in the sliding pressure chamber when the pilot is in the seated position. Additional data (and increased bit rate) is generated by allowing the fluid to quickly back flow through the unique connecting channel openings when the pilot is in the open position. Bi-directional axial movement of the poppet assembly is generated by rotating the motor causing magnets to convert the rotational motion to linear motion which opens and closes the pilot valve. The signal generated provides higher data rate in comparison with conventional pulsers because of the bi-directional pulse feature. Cleaner signals are transmitted because the pulse is developed in near-laminar flow within the uniquely designed flow channels and a water hammer effect due to the small amount of time required to close the flow throttling device. [0039] The method for generating pressure pulses in a drilling fluid flowing downward within a drill string includes starting at an initial first position wherein a pilot (that can seat within a pilot seat which resides at the bottom of the middle inner flow channel) within a lower inner flow channel is not initially engaged with the pilot seat. The pilot is held in this position with the magnetic coupling. The next step involves rotating the motor causing the magnetic fields of the outer and inner magnets to move the pilot actuator assembly thereby moving the pilot into an engaged position with the pilot seat. This motion seals a lower inner flow channel from the middle inner flow channel and forces the inner fluid into a pair of upper connecting flow channels, expanding the sliding pressure chamber, causing a flow throttling device to move up toward a middle annular flow channel and stopping before the orifice seat, thereby causing a flow restriction. The flow restriction causes a pressure pulse or pressure increase transmitted uphole. At the same time, fluid remains in the exterior of the lower connecting flow channels, thus reducing the pressure drop across the pilot seat. This allows for minimal force requirements for holding the pilot in the closed position. In the final position, the pilot moves back to the original or first position away from the pilot orifice while allowing fluid to flow through the second set of lower connecting flow channels within the lower inner flow channel. This results in evacuating the sliding pressure chamber as fluid flows out of the chamber and back down the upper flow connecting channels into the middle inner flow channel and eventually into the lower inner flow channel. As this occurs, the flow throttling device moves in a downward direction along the same direction as the flowing drilling fluid until motionless. This decreases the FTD created pressure restriction of the main drilling fluid flow past the flow throttling device orifice completing the pulse. [0040] An alternative embodiment includes the motor connected to a drive shaft through a mechanical device such as a worm gear, barrel cam face cam or other mechanical means for converting the rotational motion of the motor into linear motion to propel the pilot actuator assembly. DETAILED DESCRIPTION [0041] The present invention will now be described in greater detail and with reference to the accompanying drawing. With reference now to FIG. 1 , the device illustrated produces pressure pulses in drilling fluid flowing through a tubular drill collar and upper annular drill collar flow channel. The flow guide is secured to the inner diameter of the drill collar. The centralizer secures the lower portion of the pulse generating device and is comprised of a non-magnetic, rigid, wear resistant material with outer flow channels. [0042] In the open position the pilot is not engaged within the pilot seat allowing flow through the pilot seat. In the open position, fluid flows past the fishing head through the mud screen where a portion of the fluid flows through the pilot assembly. Fluid within the fishing head assembly flows through the upper orifice between the fishing head inner screen and the guide pole channel to allow for flow within the guide pole channel in the center of the pulser guide pole. [0043] In the closed position the pilot actuator assembly moves the pilot until it is in closed position with the pilot seat where no flow through can occur. The pilot actuator assembly is the only portion of the shaft that moves the pilot in a translational or rotational direction. The pilot orifice and pilot seat must be related to ensure hydraulic pressure differential which allows proper movement of the flow throttling device. [0044] The lower inner flow channel and the lower flow connecting channels are effectively sealed from the pilot channel so that their fluid flow is completely restricted from the interior of the FTD. As this sealing is achieved, fluid still enters the inner flow channel via the connecting channel, thus almost equalizing the pressure across the pilot assembly. The downward flow through the drill collar causes the fluid to flow past the fishing head and mud screen assembly. Fluid then flows into the middle inner flow channel through the upper flow connecting channels and into the sliding pressure chamber filling and expanding the sliding pressure chamber, causing the flow throttling device to rise along the pulser guide pole. This effectively restricts the middle annular drill collar flow channel from the lower annular drill collar flow channel, thereby generating a positive signal pulse at the throttle zone for pulse generation and corresponding signal transmittal. [0045] These conditions provide generation of pulses as the flow throttling device reaches both the closed and opened positions. The present invention allows for several sized FTD's ( FIGS. 2A-D ) to be placed in a drilling collar, thereby allowing for different flow restrictions and/or frequencies which will cause an exponential increase in the data rate that can be transmitted up hole. [0046] Positioning of the pulser assembly within the drill collar and utilizing the flow guide significantly decreases the turbulence of the fluid. The linear motion of the flow throttling device axially along the pulser guide pole is both up and down (along a bi-axial direction). [0047] Conventional pulsers require adjustments to provide a consistent pulse at different pressures and flow rates. The signal provided in conventional technology is by a pulse that can be received up hole by use of a pressure transducer that is able to differentiate pressure pulses (generated downhole). These uphole pulses are then converted into useful signals providing information for the oilfield operator, such as gamma ray counts per second, azimuth, etc. Another advantage of the present invention is the ability to create a clean (essentially free of noise) pulse signal that is essentially independent of the fluid flow rate or pressure within the drill collar. The present invention thereby allows for pulses of varying amplitudes (in pressure) and frequencies to increase the bit rate. Addition of more than one pulser assemblies would lead to an exponential increase in the data bit rate received uphole. [0048] The connecting flow channels allow for equalization of the pressure drop across the pilot to be matched by the flow throttling device (FTD) as a servo-amplifier. The primary pressure change occurs between the inner middle and inner lower flow channels providing a pressure drop created by the flow throttling device restricting the annular flow through the throttle zone. The pressure drop across the pilot is the only force per unit area that must be overcome to engage or disengage the pilot from the seated position and effect a pulse. This pressure drop across a minimal cross-sectional area of the pilot ensures that only a small force is required to provide a pulse in the larger flow area of the FTD. [0049] While the present invention has been described herein with reference to a specific exemplary embodiment thereof, it will be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention as set forth in the appended claims. The specification and drawings included herein are, accordingly to be regarded in an illustrative rather than in a restrictive sense. [0050] Magnetic coupling alleviates the concern for a rotary seal or bellow type seal which all other MWD tools have and has caused flooding and maintenance issues. BRIEF DESCRIPTION OF THE DRAWINGS [0051] FIG. 1 is an overview of an MWD. [0052] FIG. 2A is a cut-away longitudinal sectional view of the fishing head assembly. [0053] FIG. 2B is a continuation of the cross-sectional view shown in FIG. 2A and including details of the pulser, turbine, coil and motor assemblies. [0054] FIG. 2C is a continuation of FIG. 2B , illustrating more of the MWD components, particularly the various instrumentation, starting with the motor assembly through the gamma ray chassis end plug. [0055] FIG. 2D completes the MWD component description from the gamma ray end plug through the stinger nose. [0056] FIG. 3 describes the pulser system operation. [0057] FIG. 4 describes the operation of the magnetic coupling and how the pilot is actuated. [0058] FIG. 5 describes the bellows operation. [0059] FIG. 6 describes the guide pole channel and orifice chamber. DETAILED DESCRIPTION OF THE DRAWINGS [0060] The detailed description refers to the placement of a Measurement-While-Drilling (MWD) device [ 100 ] located within a drill collar [ 29 ] in a well bore incorporating fluid generally known as drilling mud [ 115 ]. Descriptions of the present disclosure are incorporated within the aforementioned description. The MWD [ 100 ] is described in greater detail referring specifically to the accompanying figures. [0061] With reference now to FIG. 1 , the device illustrated produces pressure pulses in drilling fluid flowing through a tubular drill collar [ 29 ] and upper annular drill collar flow channel [ 2 ]. The flow guide [ 23480 ] is secured to the inner diameter of the drill collar [ 29 ]. The centralizer [ 36 ] secures the lower portion of the MWD and is comprised of a non-magnetic, rigid, wear resistant material with outer flow channels. Major assemblies of the MWD are shown as the fishing head assembly [ 15000 ], flow throttling device and pulser actuator assembly complete the pulser assembly [ 170 ], turbine [ 110 ] and coil assembly [ 125 ], motor [ 130 ], various instrumentation [ 160 ], battery [ 71500 ], and stinger [ 87010 ]. [0062] FIG. 2A details the open position, drilling mud [ 115 ] flows past the fishing head assembly [ 15000 ] and fishing head outer screen [ 15020 ] where a portion of the drilling mud [ 115 ] flows through the fishing head inner screen [ 15030 ]. Drilling mud [ 115 ] within the fishing head assembly [ 15000 ] flows through the upper orifice [ 26020 ] between the fishing head inner screen [ 15030 ] and the guide pole channel [ 175 ] to allow for flow within the guide pole channel [ 175 ] in the center of the pulser guide pole [ 26010 ]. [0063] These conditions provide generation of a pulse as the flow throttling device reaches both the closed and opened positions. The present invention allows for several sized flow throttling de vices ( FIG. 1 ) to be placed in a drilling collar, thereby allowing for pressure pulse amplitudes and/or frequencies and consequential exponential increases in the data rate. [0064] In an embodiment, FIG. 2B describes the MWD device [ 100 ] which utilizes a turbine [ 110 ] residing near and within proximity of a flow diverter [ 38013 ]. The flow diverter [ 38013 ] diverts drilling mud [ 115 ] in an lower annular drill collar flow channel [ 120 ] into and away from the turbine blade [ 38230 ] such that the force of the drilling mud [ 115 ] causes the turbine blade [ 38230 ] and turbine assembly [ 110 ] to rotationally spin around a coil assembly [ 125 ]. The coil assembly [ 125 ] generates electrical power for operating the motor [ 130 ] and other instrumentation [ 160 ] ( FIG. 1 ). The motor [ 130 ] comprises a worm gear [ 26920 ], a drive shaft [ 26910 ] centrally located between the motor [ 130 ] and the outer magnets [ 26510 ] and mechanically coupled to both. Located in a position external to the magnetic pressure cup [ 26210 ] are outer magnets [ 26510 ] placed in relation to inner magnets [ 26410 ] located in a position inside the magnetic pressure cup [ 26210 ] forming a magnetic coupling. The coupling is for translating the rotational motion of the motor [ 130 ], and outer magnets [ 26510 ] to linear motion for the inner magnets [ 26410 ] via a magnetic polar interaction. The linear motion of the inner magnets [ 26410 ] help move the pilot actuator assembly [ 135 ], comprised of the rear pilot shaft [ 26240 ], front pilot shaft [ 26230 ] and pilot [ 26220 ], linearly moving the pilot [ 26220 ] into the pilot seat [ 140 ] closing the pilot seat orifice [ 145 ] lifting the flow throttling device [ 26150 ] into the flow throttling device orifice [ 150 ] thereby generating a pressure pulse. A pilot valve [ 26225 ] is comprised of the pilot [ 26220 ], the pilot seat [ 140 ] and the pilot seat orifice [ 145 ]. Further rotation of the motor [ 130 ], drive shaft [ 26910 ] and outer magnets [ 26510 ] move the pilot actuator assembly [ 135 ] and pilot [ 26220 ] away from the pilot seat [ 140 ] causing the flow throttling device [ 26150 ] to move away from the flow throttling orifice [ 150 ] thereby generating a negative pressure pulse. The inner magnets [ 26410 ] are isolated from the drilling mud [ 115 ] via a double rolling bellows [ 26310 ] which is described further in FIG. 4 . A pulse in the drilling mud [ 115 ] is sensed by the uphole system and communicated, optionally with wireless devices, to a computer [ 165 ](not shown) for interpretation. [0065] Additionally, description of FIG. 2B shows the turbine [ 110 ] which resides within the lower annular flow channel [ 120 ] of the flow guide [ 23480 ]. The lower annular flow channel [ 120 ] has diverting vanes [ 38013 ] that direct the flow of the drilling mud [ 115 ] through and around the surface of the turbine [ 110 ]. The diverter vanes [ 38013 ] project from the flow guide extension [ 26710 ] in a fashion so as to direct the flow of the drilling mud [ 115 ] to move the turbine blade [ 38230 ] and attached turbine assembly [ 110 ] thereby changing the linear motion of the drilling mud [ 115 ] into rotational motion of the turbine assembly [ 110 ]. The turbine shroud [ 38310 ] contains magnets [ 155 ] that rotate with the motion of the turbine [ 110 ] around a coil assembly [ 125 ] causing electrical power to be generated for the operation of the motor [ 130 ]. The outside diameter of the turbine blade [ 38230 ] is smaller than the flow guide extension [ 26710 ] inner diameter, thereby allowing the turbine [ 110 ] to be removed concurrently with the pulser housing [ 26810 ] from the MWD device [ 100 ]. The configuration of the turbine blade [ 38230 ] and flow diverter [ 38013 ] may be of various angles depending on the drilling conditions. [0066] Additionally the electrical power is used for operation of various instrumentation [ 160 ] ( FIG. 1 ) such as accelerometers, photo-multiplier tubes (PMT), crystal gamma ray scintillators and other useful instrumentation. Excess power provides charging for the onboard battery [ 71500 ]( FIG. 1 ) for storage and use under certain conditions where the coil assembly [ 125 ] does not generate enough power to operate the MWD device [ 100 ] under no flow conditions [0067] The velocity and consistency of the drilling mud [ 115 ] traveling through the annular flow channel [ 120 ] may vary due to wellbore conditions generally providing varying forces on the turbine [ 110 ]. The varying forces cause the turbine [ 110 ] to spin at different velocities exhibiting a wide range of power to be developed by the coil assembly [ 125 ]. Fluctuations in the power are regulated through an electrical regulation circuit. [0068] The motor [ 130 ] receives a signal from a computer [ 165 ](not shown) that is onboard the MWD device [ 100 ] to move the drive shaft [ 26910 ]. The motor [ 130 ] may be synchronous, asynchronous or stepper and is activated to fully rotate or to rotationally increment various degrees, depending on the wellbore conditions or the observed signal intensity and/or duration. [0069] FIG. 2C shows the section of the MWD device [ 100 ] containing various instrumentation [ 160 ], starting with motor [ 130 ]. Standard instrumentation, known to those skilled in the art, may include but are not limited to accelerometers, photo-multiplier tubes (PMT), crystal gamma ray scintillators and other useful instrumentation. [0070] FIG. 2D shows the final section of the MWD device [ 100 ] including the battery [ 71500 ], the stinger [ 87010 ] and the stinger nose [ 87020 ]. [0071] Positioning of the flow throttling device assembly [ 26150 ] ( FIG. 3 ) within the drill collar [ 29 ] and utilizing the flow guide [ 23480 ] significantly decreases the turbulence of the drilling mud [ 115 ]. The force required to move the pilot [ 26220 ] into or out of the pilot seat [ 140 ] is minimal. Operational power consumption to retain the pilot in any position is less than current MWD technology. The linear motion of the flow throttling device [ 26150 ] axially along the pulser guide pole [ 26010 ] is both up and down (along a bi-axial direction). [0072] FIG. 3 shows the pulser assembly [ 170 ] within a drill collar [ 29 ] when in the closed position the pilot actuator assembly [ 135 ] moves the pilot [ 26220 ] until it is in closed position with the pilot seat [ 140 ] where no flow through can occur. The front pilot shaft [ 26230 ] is the only portion of the pilot actuator assembly that moves the pilot [ 26220 ] in a translational or rotational direction. [0073] For FIG. 3 , when the pilot is in closed position, the guide pole channel [ 175 ] and the lower flow connecting channels [ 23 ] are effectively sealed so that drilling mud [ 115 ] flow is completely restricted through the pilot orifice. As this sealing is achieved, drilling mud [ 115 ] still enters both the guide pole channel [ 175 ] and separately, the connecting channels [ 23 ], thus almost equalizing the pressure across the pilot [ 26220 ]. The drilling mud [ 115 ] flows through the guide pole channel [ 175 ] causing the flow throttling device [ 26150 ] to rise along the pulser guide pole [ 26010 ]. This effectively restricts the middle annular drill collar flow channel [ 305 ] from the lower annular drill collar flow channel [ 120 ], thereby generating a positive signal pulse at the throttle zone for pulse generation [ 14 ] and corresponding signal transmittal. [0074] In FIG. 4 starting from an outside position and moving toward the center of the pulser assembly [ 170 ] comprising a pulser housing [ 26810 ] of a non-magnetic material, a magnetic pressure cup [ 26210 ], which is also comprised of a non-magnetic material, and encompassed by the outer magnets [ 26510 ]. The outer magnets [ 26510 ] may comprise several magnets, or one or more components of magnetic or ceramic material exhibiting several magnetic poles within a single component. Additionally the magnetic pole positions may be customizable, depending on the drilling conditions, to achieve a clear pressure signal. The outer magnets are housed in an outer magnet housing [ 26515 ] that is attached to the drive shaft [ 26910 ]. Within the magnetic pressure cup [ 26210 ] is housed the inner magnet assembly, that contains the pilot actuator assembly [ 135 ] comprised of the rear pilot shaft [ 26240 ] linearly engaged in a front pilot shaft [ 26230 ], which is moved longitudinally in the center of the pulser assembly [ 170 ]. Within the magnetic pressure cup [ 26210 ] is the rear pilot shaft [ 26240 ], also comprised of non-magnetic material. [0075] The outer magnets [ 26510 ] and the inner magnets [ 26410 ] are placed so that the magnetic polar regions interact, attracting and repelling as the outer magnets [ 26510 ] are moved about the inner magnets [ 26410 ]. Using the relational combination of magnetic poles of the moving outer magnets [ 26510 ] and inner magnets [ 26410 ] causes the inner magnets [ 26410 ] with the rear pilot shaft [ 26240 ], to move the pilot actuator assembly [ 135 ] linearly and interactively as a magnetic field coupling. The linear motion is along the rear pilot shaft [ 26240 ], through the front pilot shaft [ 26230 ], the bellows [ 26310 ] and to the pilot [ 26220 ] thereby opening or closing the passage between the pilot [ 26220 ] and the pilot seat [ 140 ]. The use of outer magnets [ 26510 ] and inner magnets [ 26410 ] to provide movement from rotational motion to linear motion also allows the motor [ 130 ] ( FIG. 2B ) to be located in an air atmospheric environment in lieu of a lubricating fluid [ 180 ] environment inside the magnetic pressure cup [ 26210 ]. This also allows for a decrease in the cost of the motor [ 130 ]( FIG. 2B ), decreased energy consumption and subsequently decreased cost of the actual MWD device [ 100 ]( FIG. 1 ). It also alleviates the possibility of flooding the tool instead of the use of a moving mechanical seal. [0076] Switching fields between the outer magnets [ 26510 ] and the inner magnets [ 26410 ] provides a magnetic spring like action that allows for pressure relief by moving the pilot [ 26220 ] away from the pilot seat [ 140 ] thereby regulating the pulse magnitude. Additionally the outer magnets [ 26510 ][ 26410 ] operate in the lower pressure of the pulser housing [ 26810 ] as opposed to the higher pressure within the magnetic pressure cup [ 26210 ] allowing for a greatly reduced need in the amount of energy required by the motor to longitudinally move the pilot actuator assembly [ 135 ]. [0077] The front pilot shaft [ 26230 ] passes through the anti-rotation block [ 26350 ] located below the bellows [ 26310 ]. The anti-rotation block [ 26350 ] located near the bellows is secured to the inside of the magnetic pressure cup [ 26210 ] and restricts the rotational movement of the front pilot shaft [ 26230 ]. [0078] Referring to FIG. 5 , an embodiment of the bellows [ 26310 ] includes sealing a portion of the surface of the front pilot shaft [ 26230 ] engaging around a pilot shaft land [ 26351 ] and the interior of the hollow magnetic pressure cup [ 26210 ]. Sealing of the bellows [ 26310 ] keeps drilling mud [ 115 ] from entering the bellows chamber [ 185 ] and intermingling with the inner magnet chamber lubricating fluid [ 180 ] when the pilot [ 26220 ] is moved to an open position off the pilot seat [ 140 ]. Another embodiment is to allow the bellows [ 26310 ] to move linearly, concurrent with the front pilot shaft [ 26230 ]. The design of the bellows [ 26310 ] interacting with the front pilot shaft [ 26230 ] and the bellows chamber [ 185 ] allow the bellows [ 26310 ] to conform to the space constraints of the bellows chamber [ 185 ] providing flexible sealing without the bellows [ 26310 ] being displaced by the drilling mud [ 115 ]. It was also found that the double loop [ 190 ] configuration of bellows [ 26310 ] consumes much less energy than previous designs thereby reducing the overall consumption of energy. Energy consumption is also reduced by pre-filling the bellows chamber [ 185 ] with appropriate lubricating fluid [ 180 ]. This allows for reduction of pressure differential on both sides of the bellows [ 26310 ]. The smaller pressure differential enhances performance by the bellows [ 26310 ] and minimizes wear and energy consumption. The lubricating fluid [ 180 ] may be petroleum, synthetic or bio-based and should exhibit compression characteristics similar to hydraulic fluid. The double loop [ 190 ] configuration of the bellows is designed to minimize energy consumption. [0079] FIG. 6 shows another embodiment of the present disclosure pertaining to the configuration of the guide pole channel [ 175 ] and orifice chamber [ 200 ] in the proximity of the pilot seat [ 140 ] and pilot seat orifice [ 145 ] When the pilot [ 26220 ] is in contact with the pilot seat [ 140 ] the flow throttling device [ 26150 ] moves toward the flow throttling device seat [ 210 ]. Inversely, when the pilot [ 26220 ] is not contacting the pilot seat [ 140 ] the flow throttling device [ 26150 ] withdraws from the flow throttling device seat [ 210 ]. The pressure differential between the drilling mud [ 115 ] pressure and the orifice chamber [ 200 ] moves the flow throttling device [ 26150 ] more rapidly, enabling a more forceful restriction of the flow throttling device orifice [ 150 ] and a more defined pulse and therefore clearer signals which are more easily interpreted.

Disclosed are a system, device, and method for generating pulse signals that correlate to geological information in a wellbore. The system and method comprises a pulse generating device longitudinally and axially positioned within an annular drill collar flow channel such that the drilling fluid flows through the annular drill collar flow channel and the drilling fluid is guided into two sets of selectively reversible flow, upper and lower flow connecting channels, wherein the connecting channels are connected to an inner flow channel and the annular drill collar flow channel, and wherein the annular drill collar flow channel is acted upon by one or more flow throttling devices thereby transmitting signals. The device utilizes a turbine residing near and within proximity of a flow diverter that diverts drilling mud into and away from turbine blades such that the force of the drilling mud causes the turbine blades and the turbine to rotationally spin around a coil assembly.

You are an expert at summarizing long articles. Proceed to summarize the following text: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to construction, and more particularly, to a decking assembly and a method to construct a deck. [0003] 2. Description of the Related Art [0004] Several designs for decking systems have been designed in the past. None of them, however, include clips with tabs that frictionally fit into corresponding slots on the edge of planks or in keyholes on the underside of planks. [0005] No other decking system designed in the past is as well suited for installations where the area adjacent to the footprint of the deck is limited. The present invention provides a cutout feature on the edge of the plank to facilitate the clip engaging into the plank. [0006] None of the existing decking systems have ridges and nubs on clips to more securely hold planks to deck frame assembly. Said ridges also provide a gap between the clip and plank that reduces the risk of rot or discoloration of the plank. [0007] Applicant believes that the closest reference corresponds to U.S. Patent Application Publication No. 2006/0283122 by Roy Burgess, Et. Al. However, it differs from the present invention because the Burgess application does not provide a clip with multiple fasteners, does not provide a clip with ribs or nubs and does not provide periodic cutouts or keyholes in the plank to facilitate engagement of the clip to the plank. [0008] Another reference teaching a decking technology is found in U.S. Pat. No. 6,651,398 issued to Karl Gregory. However, it differs from the present invention because the Gregory patent does not provide a clip with multiple fasteners, does not provide a clip with ribs or nubs and does not provide periodic cutouts or keyholes in the plank to facilitate engagement of the clip to the plank. [0009] Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention. SUMMARY OF THE INVENTION [0010] It is one of the main objects of this invention to provide a decking system comprising a plurality of adjoining planks, each having a first side and an opposing second side, a top surface and a bottom surface, at least one of said opposing sides of each deck member having a slot therein, a plurality of clips each having a trunk and a head sized and configured so that said trunk is disposed between adjoining planks and said head is disposed into said slot in side of said planks and a substrate onto which said clips are affixed. In an alternate embodiment said clips have one or more parallel bores that terminate on the upper end off center on the upper side of said head and on the lower end in the center of the bottom side of said trunk. In another alternate embodiment the edges of the head of said clips have tabs and the slot in said planks have a complimentary profile to receive said tabs. In yet another embodiment the slot on said plank has intermittent cutouts on the bottom side of said slot dimensioned to fit over the head of said clips. In another embodiment said clips have ridges and/or nubs on said trunk and/or the underside of said head. In another embodiment the head of said clip is made of metal and the trunk of said clip is made of plastic. [0011] Another object of the present invention is to provide a decking system comprising a plurality of adjoining planks, each having a first side and an opposing second side, a top surface and a bottom surface, said bottom surface of each deck member having a keyhole slot therein, a plurality of clips each having a trunk and a head sized and configured so that said head is disposed into said keyhole slot and a substrate onto which said clips are affixed. [0012] Another object of the present invention is to provide a decking system comprising a plurality of adjoining planks, each having a first side and an opposing second side, a top surface and a bottom surface, said bottom surface of each deck member having a slot therein, a plurality of clips each having a trunk and a head sized and configured so that said head is disposed into said slot and a substrate onto which said clips are affixed. [0013] It is one of the objects of the present invention to provide a decking assembly and method of installing said decking assembly. [0014] It is another object of this invention to provide a decking assembly that securely holds plank to the deck substrate. [0015] It is still another object of the present invention to provide a decking assembly that reduces the visibility of decking hardware on the finished deck. [0016] It is another object of this invention to provide a decking system that permits the easy replacement of individual planks. [0017] It is an object of this invention to provide a decking system with a clip that reduces the occurrence of rot and discoloration of the plank. [0018] It is an object of this invention to provide a decking system that can be installed in a confined area. [0019] It is another object of this invention to provide a decking system that reduces the possibility of fasteners backing-out and thereby reduces a hazard to a user. [0020] It is yet another object of this invention to provide such an assembly that is inexpensive to manufacture and maintain while retaining its effectiveness. [0021] Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon. BRIEF DESCRIPTION OF THE DRAWINGS [0022] With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which: [0023] FIG. 1 shows an exploded perspective view of an embodiment of the present invention. [0024] FIG. 2 is an elevation view of a series of clips and planks. [0025] FIG. 3 is a cross section of a perspective view of an alternate embodiment of a deck clip. [0026] FIG. 4 is a perspective view of a deck clip attached to a substrate. [0027] FIG. 5 represents a perspective view of an alternate embodiment a clip. [0028] FIG. 6 shows a perspective view of the bottom side of the clip shown in FIG. 5 . [0029] FIG. 7 illustrates a perspective view of an alternate embodiment of a clip. [0030] FIG. 8 shows a perspective view of the bottom side of the deck clip shown in FIG. 7 . [0031] FIG. 9A is a perspective view of the bottom side of an alternate embodiment of a clip. [0032] FIG. 9B is a perspective view of an alternate embodiment of a clip. [0033] FIG. 10A is a perspective view of an alternate embodiment of a clip. [0034] FIG. 10B is a perspective view of plank used with the clip shown in FIG. 10A . [0035] FIG. 10C is a perspective view of an embodiment of a clip used with the plank shown in FIG. 10B . [0036] FIG. 11A is a perspective view of an alternate embodiment of a clip. [0037] FIG. 11B is a perspective view of plank used with the clip shown in FIG. 11A . [0038] FIG. 11C is a perspective view of an embodiment of a clip used with the plank shown in FIG. 11B . [0039] FIG. 12A is a perspective view of an alternate embodiment of a clip. [0040] FIG. 12B is a perspective view of plank used with the clip shown in FIG. 12A . [0041] FIG. 12C is a perspective view of an embodiment of a clip used with the plank shown in FIG. 12B . [0042] FIG. 13 is a perspective view of the bottom side of an alternate embodiment of a plank. [0043] FIG. 14 is a perspective view of the bottom side of an alternate embodiment of a plank. [0044] FIG. 15 is a perspective view of an alternate embodiment of a clip. [0045] FIG. 15A is a perspective view of an alternate embodiment of plank used with the clip shown in FIG. 15 . [0046] FIG. 16 is a perspective view of the bottom side of an alternate embodiment of a plank. [0047] FIG. 16A is a perspective view of an alternate embodiment of a clip. [0048] FIG. 17 is a perspective view of the bottom side of an alternate embodiment of a plank. [0049] FIG. 18 is a plan view of the bottom side of the plank shown in FIG. 17 . [0050] FIG. 19 is a perspective view of the bottom side of an alternate embodiment of a clip. [0051] FIG. 20 is a cross-section of a perspective view of the clip shown in FIG. 19 . [0052] FIG. 21 shows a perspective view of the preferred embodiment of a clip. [0053] FIG. 22 shows a cross sectional perspective view of the deck clip shown in FIG. 21 . [0054] FIG. 23 shows a perspective view of an alternate embodiment of a deck clip. [0055] FIG. 24 is an elevation view of a series of clips and planks. [0056] FIG. 25 shows a perspective view of an alternate embodiment of a clip. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0057] Referring now to the drawings, where the present invention, a decking system, as shown in FIG. 1 is generally referred to with numeral 10 , it can be observed that it basically includes a plurality of clips 204 that attach planks 206 to a plurality of joists 202 which act as a substrate. [0058] In a typical installation a deck frame assembly 200 is constructed to support planks 206 . The deck frame assembly 200 is comprised of, inter alia, a plurality of joists 202 that are attached at each end to a girder 210 by a fastener 208 to form a unitary frame. Said fastener 208 may be a nail, screw, bolt, hanger or other fastener or adhesive. A plurality of clips 204 are attached to the top side of said joists 202 . In the embodiment of the present invention shown in FIG. 1 said plank 206 slides onto the clips 204 to hold the plank 206 securely to the joists 202 . Clips 204 on a joist 202 are typically spaced apart a distance complimentary to the width of the planks 206 . [0059] Said plank 206 , in this embodiment or any of the following embodiments, is typically is made of natural wood and also could be made of any of a wide variety of natural woods, engineered wood products, composite boards, synthetic boards, polymer boards, metal, stone, masonry, glass or any other suitable solid material. [0060] FIG. 2 illustrates an embodiment of the present invention where end-clips 222 and clips 226 interface with planks 220 . The shape of the edge of the plank 220 is formed to complement the shape of the head of the end-clips 222 and clips 226 and firmly hold the plank to the deck frame assembly 200 as shown in FIG. 1 . In one possible configuration of the invention the end-clip 222 secures the plank 220 on the edge of the frame assembly 200 and the clips 226 are utilized between planks 220 . Both the end-clips 222 and the clips 226 are secured to a joist by a fastener 224 such as a screw, nail, bolt, adhesive or other fastener. [0061] FIG. 3 shows a fastener 246 , in this example a screw, penetrating a clip through a bore 248 that passes through the head 240 and trunk 244 of the clip. Optionally, the top side of the bore 248 is countersunk to permit the head of the fastener 246 to be flush with the top surface of the head 240 . [0062] Now referring to FIG. 4 where a clip 264 is shown attached to a joist 260 with a fastener 262 . Said clip 264 is oriented on said joist 260 to permit the longer dimension of a plank 206 (shown in FIG. 1 ) to be oriented perpendicular to the longer dimension of the joist 260 . Said fastener 262 may be a screw, nail, bolt, adhesive or other fastener. [0063] Referring to FIG. 5 where an embodiment of a clip is shown that comprises, inter alia, a trunk 100 and a head 102 . Extending through the height of the trunk 100 and head 102 is a bore 104 . The bore 104 is dimensioned to receive a fastener, such as a screw, nail, bolt or other fastener. Optionally, there are ridges 106 formed integrally with the vertical surface on the side of the trunk 100 . Said ridges 106 act to maintain an airspace between the trunk 100 and a plank (not shown in FIG. 5 ). Said ridges 106 may also improve the frictional grip the trunk 100 has with plank (not shown in FIG. 5 ). [0064] The clip shown in FIG. 5 , or any of the variations and embodiments of the clip, may be made out of a wide variety of rigid or semi-rigid materials. A preferred material for many applications is a single piece of synthetic polymer or metal. For some applications it may be preferable to fabricate the clip shown in FIG. 5 from multiple materials such as, for example, a synthetic trunk 100 and a metallic head 102 . [0065] Now referring to FIG. 6 where the bottom side of the clip in FIG. 5 is shown. In this view said ridges 106 are shown in more detail. On the bottom side of said head 102 are optional nubs 108 . The nubs 108 promote airflow and grip between anything coming into contact with the head 102 . The interior of the trunk 100 may optionally have a cavity 112 to lighten the clip and reduce the material necessary to construct the clip. A rib 110 may span the width of the trunk 100 to add strength and rigidity to the clip. The rib 110 may also be traversed by a bore 104 dimensioned to accept a fastener as pass through the clip from the top to the bottom and into a substrate. Any of the various embodiments of the clips as shown in the following figures may optionally also include a cavity and rib similar to the cavity 112 and rib 110 as shown in FIG. 6 . [0066] FIGS. 7 and 8 show an alternate embodiment of a clip that is comprised of, inter alia, a trunk 118 , a head 116 , tabs 114 , bores 120 , nubs 124 and ridges 122 . Said bores 120 pass through the head 116 and through the bottom surface 126 of the trunk 118 . Optionally, the upper end of the bore 120 me be counter sunk to permit a fastener to be flush to the surface of the head 116 . Each of the outer edges of the head 116 has a tab 114 to enhance the engagement of the tab 114 with a plank. The bottom surface of the head has raised nubs 124 and the side walls of the trunk has ridges 122 that, inter alia, hold a plank apart from the clip to provide drainage, airflow and an improved frictional grip. [0067] FIG. 9A shows the bottom side of an embodiment of a clip comprising, inter alia, a trunk 164 , a head 166 and bores 162 . The trunk 164 has a bottom surface 160 where said bores 162 terminate. Said bores 162 are dimensioned to accept a fastener such as a screw, bolt, nail, adhesive or other fastener. For some decks it may be preferable for the clip to have a single bore instead of the two bores 162 shown in FIG. 9A . Any of the clips described above or below may have one or two bores dimensioned to accept a fastener. [0068] Now referring to FIG. 9B where an alternate embodiment of a clip is shown comprising, inter alia, of a trunk 182 , a head 180 and a bore 184 . The bore 184 passes through the trunk 182 and head 180 . Said bore 184 is dimensioned to accept a fastener such as a screw, bolt, nail, adhesive or other fastener. [0069] FIG. 10A shows an embodiment of a clip 300 comprised of, inter alia, a head 302 , a trunk 308 and a bore 304 . FIG. 10B shows a portion of a plank 310 with a slot 312 . The clip 300 in FIG. 10A is typically used in conjunction with the plank 310 with slot 312 shown in FIG. 10B . In typical use a fastener is placed through the bore 304 on the clip 300 to secure the clip 300 to a substrate such as the joist 260 in FIG. 4 . The edge of the head 302 engages into the slot 312 to hold the plank 310 to a joist. The height of the trunk 308 is dimensioned to position the head 302 at the same height as the slot 312 . FIG. 10C shows an embodiment of an end-clip comprising a trunk 400 , head 408 and bore 406 . The end clip shown in FIG. 10C can be used where a plank such as the example in FIG. 10B is only placed on one side of the end-clip and the head 408 engages slot 312 . [0070] FIG. 11A shows an embodiment of a clip 330 comprised of, inter alia, a head 332 , a trunk 342 , a tab 334 , a tab 340 and bores 338 . FIG. 11B shows a portion of a plank 346 with a slot 348 . The clip 330 in FIG. 11A is typically used in conjunction with a plank 346 with a slot 348 shown in FIG. 11B . In typical use fasteners are placed through the bores 338 on the clip 330 to secure the clip 330 to a joist such as the joist 260 in FIG. 4 . The edge of the head 332 and the tab 340 engage into the slot 348 to hold the plank 346 to the joist. Tab 334 engages into another section of plank 346 . The height of the trunk 342 is dimensioned to position the head 332 , tab 334 and tab 340 at the same height as the slot 348 . FIG. 11C shows an embodiment of an end-clip comprising a trunk 434 , head 420 , tab 428 and bores 432 . The end-clip shown in FIG. 11C can be used where a plank such as the example in FIG. 11B is only placed on one side of the end-clip and the head 420 and tab 428 engage slot 348 . [0071] FIG. 12A shows an embodiment of a clip 360 comprised of a head 364 , a trunk 372 , a tab 362 , a tab 370 and a bore 366 . FIG. 12B shows a portion of a plank 382 with a slot 380 . The clip 360 in FIG. 12A is typically used in conjunction with the plank 382 with slot 380 shown in FIG. 12B . In typical use a fastener is placed through the bore 366 on the clip 360 to secure the clip 360 to a joist such as the joist 260 in FIG. 4 . The edge of the head 364 and the tab 370 engage into the slot 380 to hold the plank 382 to the joist. Tab 362 engages into another piece of plank 346 . The height of the trunk 372 is dimensioned to position the head 364 , tab 362 and tab 370 at the same height as the slot 380 . FIG. 12C shows an embodiment of an end-clip comprising a trunk 450 , head 448 , tab 442 and bores 452 . The end clip shown in FIG. 12C can be used where a plank such as the example in FIG. 12B is only placed on one side of the end-clip and the head 448 and tab 442 engage slot 380 . [0072] Referring to FIG. 13 , a perspective view of an alternate embodiment of a plank 474 is shown. On the bottom edge 470 is a keyhole 476 that is comprised of an edge 468 , an edge 464 , an edge 482 , an edge 477 , a tab 460 and a tab 462 . Said edges 468 , 464 , 482 , 477 have a height less than that of edge 478 of the plank 474 so that the depth of the keyhole 476 does not extend entirely through the plank 474 and the upper surface 472 remains intact. This embodiment can be best used with a clip such as the clips as shown in any one of FIG. 9B , 10 A, 16 A, 19 , 21 , 23 or 25 but other clip shapes may also work well in particular decking applications. In a typical installation of this embodiment of the plank 474 , clips such as the clip shown in FIG. 23 are fastened to joists similar to the configuration in FIG. 1 of joists 202 , clips 204 and girders 210 . Keyholes 476 are spaced periodically on the bottom edge 470 of the plank 474 at the same distance apart as the joists 202 are spaced apart. The clips 204 are fastened to the joists 202 along the top of the joists 202 . The clips 204 are spaced apart on a joist 202 sufficiently to permit a series planks 474 to be laid side by side in contact with the joists 202 . To secure a plank 474 to the joists 202 the wider part of the keyhole 476 is fit over the head 786 of the clip shown in FIG. 23 . The plank is then slid so that said tab 460 and tab 462 fit under the head 786 of the clip thereby preventing the plank 474 from lifting away from the joists 202 . To remove or replace any of the planks 474 the individual plank 474 can simply be slid to permit the clip to be removed from the keyhole 476 without the necessity of removing adjacent planks 474 . [0073] Referring to FIG. 14 , a perspective view of an alternate embodiment of a plank 500 is shown. On the bottom edge 514 is a keyhole 506 that is comprised of an edge 508 , a tab 510 and a tab 512 . Said edge 508 has a height less than that of edge 502 so that the keyhole 506 does not extend entirely through the plank 500 and the upper surface 504 remains intact. This embodiment can be best used with a clip such as the rounded head clips as shown in any one of FIG. 9B , 16 A, 23 or 25 but other clip shapes may also work well in particular decking applications. In a typical installation of this embodiment of the plank 500 , clips such as the clip shown in FIG. 9B are fastened to joists similar to the configuration in FIG. 1 of joists 202 , clips 204 and girders 210 . Keyholes 506 are spaced periodically on the bottom edge 514 of the plank 500 at the same distance apart as the joists 202 are spaced apart. The clips 204 are fastened to the joist 202 along the top of the joist 202 . The clips 204 are spaced apart on a joist 202 sufficiently to permit a series of planks 500 to be laid side by side in contact with the joists 202 . To secure a plank 500 to the joists 202 the wider part of the keyhole 506 is fit over the head 180 of the clip shown in FIG. 9B . The plank is then slid so that said tab 510 and tab 512 fit under the head 180 of the clip thereby preventing the plank 500 from lifting away from the joists 202 . To remove or replace any of the planks 500 the individual plank 500 can simply be slid to permit the clip to be removed from the keyhole 506 without the necessity of removing adjacent planks 500 . [0074] Another advantage of the keyhole design as shown in FIGS. 13 and 14 is that the plank may be installed where there is limited area around the deck because the plank need only be slid, for example, a few inches to engage a clip within the keyhole contrasted to sliding the plank the entire length of the plank as necessary for some of the other embodiments of this invention described herein. [0075] Referring now to FIGS. 15 and 15A where yet another embodiment of a clip 558 and a plank 584 combination is shown. Said clip 558 is comprised of, inter alia, a trunk 560 , bores 566 , tab 556 , tab 550 , a head 564 and nubs 552 . Said bores 566 go through the head 564 and trunk 560 . Said bores are dimensioned to accept a fastener such as a bolt, screw, nail or other available fastener. Said bores 566 optionally have a countersink in the end near the head 564 to permit a fastener to fall flush to or below the surface of the head 564 . Said tabs 556 and 550 optionally have a series of nubs 552 comprised of protrusions on the upper edges of tabs 556 and 550 to create a gap and increase the strength of the connection when the clip 558 is engaged into a plank 584 . Optionally ridges may be formed into the trunk 560 similar in form the ridges 106 shown in FIG. 6 . In a preferred embodiment of the clip 558 the entire clip 558 is made out of a synthetic polymer or plastic. In another preferred embodiment the clip 558 could be made out of metal or a metal alloy. In yet another preferred embodiment the clip 558 has a head 564 of metal and the balance made of a polymer. [0076] Said plank 584 has, inter alia, an upper surface 570 , slot 578 , tab 586 , roundover 572 , tab 582 and slot 580 . In a preferred embodiment at least two clips 558 are used to secure a plank 584 to a joist. A typical application of this embodiment is shown in FIG. 1 where the clip 204 and the plank 206 in FIG. 1 are replaced by clip 558 and plank 584 , respectively. Clips 558 are fastened to the joists 202 and the plank 584 is slid between clips 558 where tab 550 fits under tab 586 and edge 562 fits into slot 578 . Another clip 558 similarly fits into slot 580 and tab 582 on the opposite edge of the plank 584 . Said roundover 572 is primarily cosmetic and may optionally be present on the plank 584 . In a preferred embodiment said plank 584 is constructed of solid wood but may also be made of engineered wood, synthetic material, metal, masonry or other solid material. [0077] FIGS. 16 and 16A show another alternate embodiment of a complimentary plank 624 and clip 628 . Said plank 624 is comprised of, inter alia, a bottom surface 622 , tab 620 , tab 614 , top surface 602 and slot 608 . Said slot 608 is formed along the length of the plank 624 . Said tab 620 and tab 614 partially cover the slot 608 . Said clip 628 is comprised of, inter alia, bores 640 , head 638 and trunk 630 . In the preferred application of the clip 628 , a series of clips 628 are fastened to joists similar to the joists 202 in FIG. 1 . The head 638 of the first clip 628 in the series of clips is slid into the slot 608 of the plank 624 and the trunk 630 is fit between tab 620 and tab 614 to secure the plank 624 to the joist 202 . The plank 624 is successively slid onto subsequent clips 628 to secure the plank 624 to the joists 202 . In one of the preferred embodiments the clip 628 is made of plastic but it could also be effective if made out of any rigid polymer, metal or other solid material or combination of solid materials. [0078] Now referring to FIGS. 17 and 18 where an alternate embodiment of a plank 701 is shown that is comprised of, inter alia, a lower tab 704 , an upper tab 710 , a slot 708 and cutouts 702 . Said slot 708 is bounded by the lower tab 704 and the upper tab 710 . In the preferred embodiment the plank 701 is made from wood, engineered wood, polymer, metal or masonry but any other solid material could be utilized. [0079] The plank 701 is used similar to the deck frame assembly 200 in FIG. 1 where clips 204 are fastened to joists 202 that are supported by girders 210 . In the preferred embodiment the plank 701 is secured by a clip (for example, the clips shown in any of FIG. 5 , 6 , 9 A, 9 B, 10 A, 16 A or 19 , but any clip with a head complimentary to the slot 708 could be used) to a joist 202 . Said cutouts 702 are positioned periodically on the lower tab 704 and are spaced apart the equal to the distance between the joists 202 . When installing the plank 701 the cutouts 702 are fit over the clips 204 and the bottom surface 700 of the plank 701 rests on to the joists 202 . The plank 701 is slid along the top of the joists 202 so that the head of the clips fit into the slot 708 between the upper tab 710 and lower tab 704 . [0080] Referring to FIGS. 19 and 20 where an alternate embodiment of a clip 744 is shown comprising, inter alia, a trunk 742 , a tab 740 , a tab 746 , cutouts 748 and bores 750 . In this embodiment of the clip 744 the bores 750 are dimensioned to accept a fastener such as a screw, nail or bolt. Said bores 750 pass through the trunk 742 from the side of the trunk 742 under the tab 746 to the bottom surface of the trunk 754 . Said tab 746 has cutouts 748 adjacent to the bores 750 to permit passage of a fastener and a tool to secure the fastener. One of the advantages of the position of the bores 750 is to permit a plank, such as the plank 310 shown in FIG. 10B , to be laid onto a supporting joist before the clip 744 . In this installation method a plank, for example plank 310 , is laid onto a joist then a first clip 744 is inserted into the slot 312 and fastened to the joist. Then a second plank 310 is laid onto the joist and its slot 312 is pressed into the first clip 744 and a second clip 744 is inserted into the slot 312 on the side of plank 310 opposite the first clip 744 and the second clip 744 is then fastened to the joist to secure the second plank 310 . This method is repeated until the planks 310 cover the substrate. The installation method described above is similar to that shown and described below in FIG. 24 . [0081] Now referring to FIGS. 21 and 22 where the preferred embodiment of a clip 768 is shown that comprises, inter alia, a bore 778 , a trunk 772 and a head 770 . Said trunk optionally includes a series of ridges 776 to provide an airspace between the clip 768 and any plank material. One of the distinguishing features of this clip 768 is that the bore 778 passes through the head 770 off of center and exits through the bottom side of the trunk 772 at or near its center. Similar to the clip 300 shown in FIG. 10A , clip 768 could have multiple bores 778 , each angled through the trunk 772 . Said bore 778 is dimensioned to accept a fastener 774 such as a screw, bolt, nail or other similar means. Optionally, the upper end of the bore 778 may have a countersink to permit the head of the fastener 774 to fall below the surface of the head 770 . In a preferred embodiment, this clip 768 is made of plastic or metal but could also be made of any durable, rigid material or combination of materials. [0082] FIG. 23 is an alternate embodiment of a clip that comprises, inter alia, a trunk 782 , a bore 784 and a head 786 . The distinguishing feature that this clip demonstrates is the rounded shape of the head 786 as well as the angular edge 780 of the head 786 . The edge 780 may facilitate the clips engagement into the slot of any of the above-described planks. As in other clips described above, this clip may have more than one bore and/or have the bores at an angle not perpendicular to the surface of the head 786 . [0083] FIG. 24 is an alternate embodiment of a clip that comprises, inter alia, a trunk 802 , a bore 806 and a head 800 . The distinguishing feature that this clip demonstrates is the rounded shape of the head 800 as well as the angular edge 804 of the head 800 . The edge 804 may facilitate the clips engagement into the slot of any of the above-described planks. As in other clips described above, this clip may have more than one bore and/or have the bores at an angle not perpendicular to the surface of the head 800 . [0084] FIG. 24 is an illustration of an example of a method to install a deck comprising, inter alia, plank 790 , plank 791 , clip 793 , clip 794 , slot 795 , slot 796 , slot 797 and fasteners 792 . This method is one of the preferred methods used with clips that have bores at an angle not perpendicular to the surface of the head of the clip such as the clips shown in FIG. 19 or 21 . [0085] In this installation method a plank 791 is laid onto a joist then the slot 795 is fit into a first clip 794 . Then a second clip 793 is fitted into slot 796 on plank 791 and fastened with fastener 792 to the joist below. Then the next plank 790 is laid onto the joist and its slot 797 is fitted into the second clip 793 . This method is repeated by laying subsequent planks and then clips until the deck is completed. [0086] Generally, any of the various embodiments of the clips described above in this invention can have one or more bores, any of the shapes of the edges of their head, have ridges and/or nubs, bores can be perpendicular to the head or angular respective to the head and be made out of any of the described materials or combination of materials. Likewise, the planks can be made out of any solid material that can be shaped to have the planks slot interface with the clip. [0087] The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense.

A decking system that consists of a clip that complements a slot in deck planks to securely fasten the deck planks to a substrate such as deck or floor joists, masonry, concrete, wood or any other substrate. Generally, the clips fit into slots cut or formed into the side deck surface boards or alternatively into a keyhole on the bottom of the plank. In one of the preferred embodiments a series of clips are fastened to the substrate with a fastener such as a screw. The clips mechanically grip the plank to secure the plank to the deck joists. Ridges and/or nubs on the clips reduce the occurrence of rot or discoloration of the planks.