referring now more specifically to the drawings and fig1 in particular , numeral 20 designates the present practice device for bowling and other sports , shown in fig1 set up for bowling practice . the device includes an elongated base 22 , which is shown as being made of wood and is polished so as to permit the user to move or slide one foot in performing underhand throwing motions . other materials and surfaces for the base may also be used , i . e ., plastic , metal , etc . ; smooth finish , textured , rough , etc . the base is elongated sufficiently to accommodate a one or two - step delivery of the ball , horseshoe , or other handpiece , such as will be described later , and extends at least through the lengthwise extent of the track 24 , as viewed in fig1 . the base may also include feet 26 and a brace or braces 28 , for lateral stability . while shown in fig1 with the base extending on both sides of the track 24 , to accommodate fight and left handed users , the base may also comprise a single panel , which can be transferred from one side to the other . the track 24 is semi - circular or arcuate in shape and is designed to allow the user to move the delivery arm and hand through an ideal or idealized motion for bowling , softball pitching , horseshoes , and other sports . in bowling , for example , the arm is fully extended on the back swing and bends toward the bowler &# 39 ; s head on the follow - through , as shown by the phantom lines in fig1 . thus , the track has a relatively flat curve in the rear section , an almost perfect circle at the bottom , and a more pronounced curve at the front or finish section . similar motions are used for other sports using underhand delivery . in order to develop consistency in a sport such as bowling , the approach to the foul line and the delivery of the ball should be essentially the same each time the ball is delivered . the bowler &# 39 ; s arm must always move in the same plane and in a straight forward direction to impart the proper direction and rotation to the ball . with the present device , the user is forced to use the proper motion , without the variables inherent in actual practice bowling or when receiving bowling lessons . the idealized motion gained with the present invention can then be easily transferred to actual practice or competition . the track is height adjustable to accommodate users of any height and is provided with height - adjustable support means , such as leg assembly 30 and struts 32 . the leg assembly has a track - engaging saddle 34 which can be elevated or lowered using a pin and slot means 36 , or other stiltable height - adjusting means . for example , a racheting system may be used . alternatively , struts 32 could be used in either a vertical or the slanted position as shown in fig1 to adjust the height of the track above the base . auxiliary supports 38 may be added for stability as necessary . the track itself is formed from a suitable lightweight material such as aluminum or plastic . the track preferably has a c - shaped cross - section with a central slot 40 facing outwardly to receive the carrier on which is mounted the ball , handle , or other means . alternatively , the track can be a single curved sheet or tube of suitable material , having the same or a similar shape to that shown . in such an embodiment , the carder , as described below , would engage the track instead of tiding therethrough . the surface of the track means which contacts the carder may be coated with a substance such as that sold under the trademark teflon ® to facilitate movement in or on the track . the carrier is shown in various embodiments in fig3 through 8 . fig3 illustrates an i - shaped block means 60 . mounted on the block 60 is a replica or simulated bowling ball 62 . the ball 62 is configured to be usable by either a right or left handed bowler and can be lighter , heavier , or the same weight as a conventional ball . grooves 64 engage the facing edges 66 of the track 24 , which together define the slot 40 . where the track means comprises a single curved sheet or tubular material , the block 60 would simply be configured with essentially a c - shape , to engage the track and travel through the curve formed thereby . fig4 illustrates a different type of block means 68 . this block has radiused edges to facilitate its traveling through the track means . mounted on block 68 is a replica of a softball 70 , the ball being spaced from the block and connected thereto by a neck 72 . the neck travels through the groove 40 as the pitching motion is practiced . block means 68 , fitting inside the track , is of a sufficient width to travel easily within the confines of the track without racking or twisting . while some contact with the inner wall surfaces of the track is possible , it does not impede the motion of the particular carder . as a further aid to movement , the grooves 64 of block 60 , the outer surfaces of block 68 , and any other parts of the various block means described herein may also be coated with a non - stick material , such as teflon ® or the like . the carder embodiments shown in fig5 through 8 have a bar - shaped handle 74 . this handle is disposed at approximately a 35 ° to 45 ° angle relative to the direction of travel through the track . this angle approximates a favorable or idealized hand position for delivering a bowling ball such that an overspin is imparted to the ball upon its release in order to help propel the ball through the bowling pins . the handle 74 includes cutouts 76 which are disposed at an approximate 45 ° angle relative to the longitudinal axis of the handle . the cutouts are also disposed at approximately 90 ° relative to one another to accommodate right or left handled users . the cutouts are designed to receive the user &# 39 ; s thumb and place the thumb and fingers in the preferred position for delivering the bowling ball . this particular embodiment is shown in fig1 . as illustrated , the user &# 39 ; s hand is disposed slightly to one side of the &# 34 ; ball &# 34 ; and follows a straight ahead path from the backswing to the followthrough . when finished , the bowler &# 39 ; s thumb ends up pointing toward the eyes or forehead . as noted , this motion imparts overspin to the ball when bowling , which is desirable whether the bowler is right or left handled . while the same handle is shown in fig5 through 8 , different block means are illustrated as alternate embodiments . in fig5 a set of wheels 78 is used , the wheels being designed to ride on the inside wall surfaces of the track . in fig6 through 8 , alternate block means 80 , 82 and 84 , respectively , are illustrated . block means 84 is described in greater detail hereinbelow . a neck member 72 connects the handle to the block means and travels through the slot 40 , as described hereinabove . an additional embodiment of the present invention is shown in fig2 . in this embodiment , a tensioning device 80 is mounted at the rearmost extent of track 24 . this device includes a cable 82 with the leading end ( not shown ) attached to the block means . the rest of the cable is wound up on a spool 84 within the tensioning device . by adjusting the tension , the user can simulate the use of a heavy or light ball , or simply use the device to exercise , the primary emphasis being on upper body conditioning . the embodiments shown in fig9 through 12 illustrate the same concept as the previously described devices , but with a different structural arrangement . referring to fig9 this embodiment includes an elongated base 102 having feet 104 which may also serve as braces for the opposed sides of the base . the track 106 is semi - circular or arcuate , having the same basic shape as track 24 , shown in fig1 . the track is supported with height - adjustable support means , such as the leg assemblies 108 . the leg assemblies are designed with an outer leg 110 and a telescopically received inner leg 112 . a locking pin or bolt ( not shown ) is used to secure the leg assemblies at a desired height . track 106 may have a solid cross - section or it may be tubular , with several tubular forms illustrated in fig1 through 12 . in fig9 the track 106 is solid . fig1 shows a d - shaped , hollow , tubular track 120 . fig1 illustrates a hollow , rectangular track 122 while fig1 shows a hollow , circular track 124 . in these embodiments , the carder means is disposed around the outer perimeter of the track . the carrier means 126 , 128 and 130 , shown in fig1 through 12 respectively , have essentially the same shape as the track , with an opening or recess being provided to accommodate the supporting leg assemblies . any of the various handle configurations described earlier can be used with these embodiments , and the practice motion is the same . the outside surface of the tracks shown in fig9 through 12 , the inside surface of the carder means , or both , may have teflon ® or a similar substance applied thereto to facilitate sliding along the track . in addition , a tensioning device , as shown in fig2 can also be utilized . the user of the present device is thus able to practice virtually any sport which utilizes an underhand throwing motion . the device is adjustable to accommodate users of different heights and takes up relatively little space compared to actual practice at the bowling lanes , on a softball field , etc . utilizing the present invention allows the user to &# 34 ; groove &# 34 ; his or her swing , resulting in better control , more consistency , and better scoring or performance in the particular sport or game . thus , while an embodiment of a practice device for sports or games utilizing an underhand throwing motion and modifications thereof have been shown and described in detail herein , various additional changes and modifications may be made without departing from the scope of the present invention .
a practice device for bowling and other sports or activities that utilize an underhand throwing motion is disclosed , the device including a base , an arcuate track mounted on the base , and a carrier which engages the track . the user moves the carrier along the track , thereby practicing the idealized underhand swing motion .