now looking more closely at the drawings and particularly the embodiment shown in fig1 to 5 it will be seen that the access valve generally shown as 2 is mounted onto a catheter body 4 . the access valve has a cylindrical housing 6 into which is received a cylindrical elastomeric diaphragm 8 . the cylindrical elastomeric diaphragm 8 defines a cylindrical aperture 3 therethrough . the end of the cylindrical diaphragm 8 nearest the catheter 4 has an outwardly extending radial flange 10 which is clamped against the end of the catheter by means of the cylindrical housing 6 . the flange 7 on the cylindrical housing 6 is received in slot 9 in the catheter body 4 to hold and seal the valve 2 to the catheter body 4 . a rotary actuator 12 is mounted onto the cylindrical housing 6 and retained in position by a radial flange 11 extending from the external end of the cylindrical diaphragm . a string 14 is mounted into the rotary actuator with a knot 16 at one end and then passes through an aperture 20 in the cylindrical housing 6 and then is wound preferably twice around the cylindrical diaphragm 8 preferably in a recessed region 22 and then passes through a further aperture 24 in the cylindrical housing before being fixed by knot 18 again in the rotary actuator . rotation of the rotary actuator 12 with respect to the cylindrical housing 6 will cause the string 14 to be pulled in both directions at once and hence the cylindrical diaphragm 8 to be constricted . the internal cylindrical surface 13 of the rotary actuator 12 has a circumferential groove 15 which allows the string 14 to extend around the outside of the cylindrical housing 6 when the rotary actuator 12 is rotated . alternatively the cylindrical housing 6 may have a circumferential groove on its outer surface to allow the string 14 to extend around the outside of the cylindrical housing 6 when the rotary actuator 12 is rotated . as particularly shown in fig3 and 4 a detent arrangement having a ball 28 loaded by a spring 29 in an aperture 30 in the rotary actuator runs in a groove 32 in the cylindrical housing 6 . the groove 32 has a central recess 34 and end recesses 36 . there may also be further recesses or detents between the central recess and the end recesses . the rotary actuator may be rotated in either direction to cause constriction of the constriction valve , and the detents provide tactile feel the action of the valve . particularly as shown in fig4 when the rotary actuator is moved through perhaps 45 ° of rotation , it will be seen that the flexible member 14 has been pulled tangentially in both directions and the cylindrical diaphragm has been stretched radially inwards or constricted and the valve partially closed off . rotation of the rotary actuator back to the central position where the detent ball 28 is received in depression 34 will cause the sutures to loosen again so that the resilient cylindrical diaphragm will retain its original shape as shown in fig1 and 3 . depending upon the number of turns of the flexible member around the cylindrical diaphragm rotation of the rotary actuator may be up to 90 or more in either direction to enable complete closing off of the valve . in the embodiment of constriction valve shown in fig6 the sealing action of the valve as discussed above is assisted by means of an apertured diaphragm 40 which is also clamped between the cylindrical housing 6 and the catheter body 4 . the apertured diaphragm 40 has an aperture or a slit 41 completely through it or a half slit 41 , 43 from each side crossed at right angles to provide extra sealing for the time that the valve is opened to allow an instrument to be passed through it . the apertured diaphragm may be formed from a silicone rubber and may be formed integrally with or separately from the cylindrical diaphragm . in this embodiment the rotary actuator is be retained by a radially outwardly extending flange 42 . this flange may alternatively be positioned so that it engages in a groove on the internal cylindrical surface of the rotary actuator . the rotary actuator may be pushed on over the flange to click into position to retain it . it will be seen that by this invention there is provided an access or constriction valve arrangement which will close over a range of diameters of devices passed through the valve or can close completely down to be self sealing . throughout this specification various indications have been given as to the scope of the invention but the invention is not limited to any one of these but may reside in two or more combined together . the examples are given for illustration only and not for limitation .
an access valve for a laparoscopic device or a intraluminal deployment device has a cylindrical diaphragm with a longitudinal aperture , a flexible member is passed circumferentially around the cylindrical diaphragm and an extension arrangement to pull the flexible member radially and / or tangentially to constrict the diaphragm to at least partially close off the longitudinal aperture . a rotary actuator may be used .