as demonstrated in the accompanying drawings , the present invention is directed to a trocar assembly generally indicated as 10 and including a housing generally indicated as 12 and an elongated hollow sleeve or cannula , generally indicated as 14 and attached to one end of the housing 12 , as at 16 . the opposite end 18 of the cannula 14 is open to allow the passage of medical instruments as well as fluid there through , as will be explained in greater detail hereinafter . for purposes of clarity , the housing 12 is represented as being transparent . however , the material from which the housing , as well as the remaining trocar assembly 10 , is formed may or may not be a transparent or translucent material . in any event , the housing 12 includes a substantially hollow interior having at least one open end 20 which is oppositely disposed to the cannula 14 . the housing 12 may also include an access port or coupling 22 disposed and configured to receive a connector generally indicated as 24 for connection to a substantially conventional source of at least initially pressurized fluid . the fluid may be carbon dioxide or other commonly used gases , which are conventionally employed to inflate and expand the internal body cavity of a patient and thereby facilitate performance of the aforementioned of different types of surgical procedures by providing increased access to the body cavity . the connector 24 may include a control knob 26 which regulates fluid flow into the interior of the housing 12 through the connector 24 as is well known . the present invention also includes a valve assembly generally indicated as 30 . the valve assembly 30 comprises a valve member 32 secured to a mounting base 34 and a valve structure 36 having a valve seat 38 integrally or otherwise fixedly secured thereto . the valve member 32 is attached to the housing 12 independently of the valve structure 36 and valve seat 38 . more specifically the mounting base 34 is disposed within the hollow interior of the housing 12 immediately adjacent to the open end 20 , as best shown in fig6 . the valve member 32 is mounted within the hollow interior of the housing 12 and is dimensioned and configured to sealing engage the surrounding periphery 38 ′ of the valve seat 38 to define the valve - closed position , as will be explained hereinafter . the valve member 32 as well as the mounting base 34 may be integrally connected to one another and are formed of an elastomeric material preferably having an inherent bias . further , the interconnection between the valve member 32 and the mounting base 34 forms an integral hinge as at 35 which serves to normally bias the valve member 32 in a inwardly oriented , substantially angled incline relative to an imaginary central longitudinal axis of the hollow interior of the housing 12 . the elastomeric material from which the valve member 32 is formed allows it to be forced outwardly from its normally angled orientation , as shown in fig2 and subsequently return to its normally “ biased ” position shown in fig1 as will be explained in greater detail hereinafter . it should be emphasized that while one embodiment of the present invention defines an integral connection between the valve member 32 and the mounting base 34 , structural adaptations other than the integral hinge 35 are included within the intended spirit and scope of the present invention . for example , the valve member 32 may be connected by a variety of a different types of hinge structures ( not shown for purposes of clarity ) so as to facilitate the normal orientation of the valve member 32 in its angularly inclined position also disclosed fig4 and 6 . regardless of the specific movable interconnection between the valve member 32 and the mounting base 34 , it is to be noted that the mounting base 34 includes an opening or aperture 37 of sufficient dimension to allow passage therethrough of the elongated valve seat 38 , when in its assembled form as shown in fig1 through 3 . accordingly , upon connection of the mounting base 34 adjacent to the open end 20 of the hollow interior of the housing 12 , the valve structure 36 and valve seat 38 are operatively assembled by passing the valve seat 38 into the hollow interior of the housing 12 and into cooperative relation to the valve member 32 . with reference to fig4 the exterior periphery of the open end 20 includes thread like connector flanges 23 , which allow at least a limited amount of rotation of the valve structure 36 relative to the housing 12 in each of two opposite directions as indicated by directional arrow 40 . the connecting flanges 23 movably engage cooperatively formed structures ( not shown for purposes of clarity ) disposed on the interior of the valve structure 36 , adjacent an access opening 36 ′. therefore , it should be apparent that the valve structure 36 , and the fixedly attached valve seat 38 , are rotatable relative to the housing 12 in either of the two opposite directions , as indicated by directional arrow 40 . further , the relative disposition and configuration of the valve member 32 and the valve seat 38 serve to maintain these two elements in substantially continuous engagement with one another , as shown in fig1 through 3 , regardless of whether the valve assembly 30 is selectively disposed in a valve - closed position as shown in fig1 or a valve open - position as shown in fig2 . the versatility of the trocar assembly of the present invention is further emphasized by the ability of a user thereof to selectively dispose the valve assembly 30 in at least a partially open position , as shown in fig3 rather than the closed position of fig1 or the fully open position of fig2 . rotation of the valve structure 36 and valve seat 38 is facilitated by at least one outwardly projecting knob , flange , or like positioning member 42 . the positioning member 42 extends outwardly from the exterior surface of the valve structure 36 and is disposed and dimensioned to be manipulated by the thumb or a single finger of a user &# 39 ; s hand which serves to support and position the remainder of the trocar assembly 10 . also , a stop member 44 may be secured to the exterior surface of the housing 12 in interruptive engagement with the positioning member 42 so as to partially limit the rotation of the valve structure 36 , as it is being selectively rotated relative to the housing 12 in order to open or close the valve assembly 30 . additional structural features of the present invention include the mounting base 34 disposed in a seated or flush engagement with interior wall portions of the at least partially closed end 39 of the valve structure 36 . however , while the valve structure 36 and valve seat 38 are selectively rotatable relative to the housing 12 , the mounting base 34 and valve member 32 are not rotatable therewith . to the contrary , the mounting base 34 and attached valve member 32 are not rotatable relative to the housing 12 due to an interconnection between a key member 45 and a key slot 47 . the key member 45 is integrally or otherwise fixedly secured to the housing 12 contiguous to the open end 20 and the key slot 47 is integrally formed about the outer periphery of the mounting base 34 , as shown in fig4 and 5 . it should be apparent therefore that is as the valve structure 36 and valve seat 38 rotate relative to the housing 12 , the mounting base 34 and the valve member 32 are fixed in their indicated positions within the hollow interior of the housing 12 , at least in terms of being non - rotatable relative to the housing 12 . as set forth above , the valve member 32 has a flexible , spring like hinge portion 35 , which allows it to be moved into different angular orientations relative to an imaginary central longitudinal axis of the housing 12 . further , when the valve seat 38 is disposed in its operative , assembled position as shown in fig1 through 3 , the valve member 32 and the valve seat 38 are disposed in substantially continuous engagement with one another . moreover , rotation of the exteriorly disposed valve structure 38 , such as by manipulation of the positioning member 42 , will cause a sliding engagement between the exterior surface of the valve seat 38 and the under surface 32 ′ of the valve member 32 . the aforementioned valve - closed position of fig1 is accomplished by the valve member 32 being disposed in a substantially fluid sealing engagement over the peripheral edge 38 ′ of the valve seat 38 , such that the entire periphery 38 ′ is contacted by the undersurface 32 ′ of the valve member 32 thereby preventing fluid flow to pass there between . to the contrary and with reference to fig2 and 3 , rotation of the valve structure 38 causes a sliding engagement between either the exterior surface or surrounding periphery 38 ′ of the valve seat 38 and the undersurface 32 ′ of the valve member 32 , which forces the valve member 32 outwardly from its normally biased , angularly oriented position of fig1 and 6 . the maximum displacement of the valve member 32 is represented in the fully open position of fig2 and a somewhat lesser displacement is represented by the partially valve - open position of fig3 . other structure included in at least one embodiment of the present invention comprises an adaptor member generally indicated as 50 . the adaptor member 50 includes a cap member 52 removably or otherwise connected to the closed end 39 of the valve structure 36 . a fluid seal is accomplished between the closed end 39 and the interior of the of the adaptor structure 50 by the provision of sealing gaskets 55 and 57 , respectively formed on the exterior of the closed end 39 and the interior of the cap 52 . removable attachment between the cap 52 and the valve structure 36 is accomplished by outwardly extending , flexible fingers 58 and 59 having locking lugs 60 attached to the outer most ends thereof . the fingers 58 and 59 and their associated locking lugs 60 are formed of a flexible material and may be forced inwardly , in accordance with directional arrow 52 . the fingers 58 and 59 are disposable to allow the locking lugs 60 to pass outwardly from the interior of the cap 52 , through the receiving apertures 65 . manipulation of the fingers 58 and 59 and locking lugs 60 relative to the cap 52 facilitates removal of the cap 52 from the valve structure 36 so that it may be replaced by other adaptor members ( not shown ). the cap 52 of the adaptor member 50 includes a central passage 66 for the connection of a penetrating needle , biopsy needle , or other elongated medical instruments which successively passes through the cap 52 , elongated channel formed on the interior of the valve structure 36 , hollow interior of the housing 12 and along the length of the sleeve or cannula 14 , so as to exit from the open end 18 thereof and participate , as intended , at the surgical site . additional structure associated with the trocar assembly 10 includes finger grips 70 secured to the exterior of the housing 30 and extending outwardly therefrom in substantially opposite directions . finger grips 70 are used in conventional fashion to help secure the housing 12 as well as the cannula 14 in a proper position while manipulating a medical instrument , such as an obturator , as it penetrates into the exterior bodily tissue . other medical instrumentation may also be similarly manipulated . it should be apparent therefore that upon passage of the open end 18 of the cannula 14 into the interior of the internal body cavity , pressurized gas or fluid , such as carbon dioxide , is introduced therein causing an expansion thereof in order to provide better access thereto by the medical personnel . during such inflation and while the body cavity is maintained in its inflated state , the valve structure 36 of the valve assembly 30 is rotated so as to assume and maintain the valve - closed position , as shown in fig1 . while in the valve - closed position , a user of the trocar assembly 10 does not have to maintain any type continuous pressure on or contact with the positioning member 42 in order to maintain the valve - closed position . when it is intended to deflate the body cavity the positioning member 42 may be manipulated by the thumb or single finger of the hand holding the trocar assembly 10 and thereby rotate the valve structure 36 to assume the fully valve - open position of fig2 or the partially valve - open position of fig3 . when it is required to insert a medical instrument through the adaptor member 50 and beyond the valve assembly 30 , the valve member 32 may be automatically forced away from its sealing orientation relative to the periphery 38 ′ of the valve seat 38 by the leading end of the instrument passing through the valve seat 38 . alternatively , the valve structure 36 may be rotated to the fully or partially valve - open position shown in fig2 and 3 respectively in order to facilitate passage of any medical instrument through and beyond the valve assembly 30 and into the cannula 14 so that it can reach the surgical site . since many modifications , variations and changes in detail can be made to the described preferred embodiment of the invention , it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense . thus , the scope of the invention should be determined by the appended claims and their legal equivalents .
a trocar assembly structured to regulate fluid flow as well as the introduction of predetermined medical instrumentation into and out of a body cavity of a patient during a surgical procedure such as , but not limited to laparoscopy , endoscopy , etc . the trocar assembly includes a housing having a hollow interior secured at one end to an elongated open ended sleeve through which fluid flow and medical instrumentation passes . a valve assembly includes a valve member disposed within the hollow interior and a valve structure including a valve seat rotatably connected to the housing such that the valve seat is selectively rotatable relative to the valve member and into and out of fluid sealing engagement therewith so as to respectively define a valve - closed position and a valve - open position . the valve assembly may be rotated between the aforementioned open and closed positions utilizing one hand of the person operating the trocar assembly , wherein the valve assembly will automatically remain either in an open or closed position , without continuous pressure being exerted thereon by the personnel operating the trocar assembly .