Valves

Claim 1

A CHECK VALVE FOR ALLOWING FLUID FLOW IN A FIRST DIRECTION AND PROHIBITING FLUID FLOW IN A SECOND DIRECTION INCLUDING: A HOUSING COMPRISING A PIN SECTION THREADED TO A BOX SECTION, SAID SECTIONS HAVING CONNECTING BORES THERETHROUGH FORMING A FLOW PASSAGE THROUGHOUT THE LENGTH OF SAID HOUSING, SAID PIN SECTION HAVING AN INTERNAL ANNULAR VALVE SEAT FACING SAID BOX SECTION AND SAID BOX SECTION HAVING AN INTERNAL ANNULAR SHOULDER SPACED APART FROM AND FACING VALVE SEAT; A VALVE ASSEMBLY SLIDABLY DISPOSED WITHIN SAID HOUSING FOR LONGITUDINAL MOVEMENT BETWEEN A FULLY CLOSED POSITION WHEN SAID VALVE ASSEMBLY ENGAGES SAID VALVE SEAT AND A FULLY OPEN POSITION WHEN SAID VALVE ASSEMBLY ENGAGES SAID ANNULAR SHOULDER; SAID VALVE ASSEMBLY COMPRISING A CENTRAL VALVE BODY, A HEAD MEMBER FORMED ON ONE END OF SAID BODY AND PROVIDED WITH AN EXTERNAL ANNULAR SUBSTANTIALLY SPHERICAL FACE ENGAGEABLE WITH SAID VALVE SEAT WHEN SAID VALVE ASSEMBLY IS IN CLOSED POSITION, SAID VALVE BODY HAVING AN EXTERNAL ANNULAR INWARDLY DIVERGENT DOVETAIL SHAPED RECESS ADJACENT TO SAID HEAD MEMBER, A PLURALITY OF LEG MEMBERS FORMED ON THE OTHER END OF SAID VALVE BODY EXTENDING LONGITUDINALLY BEYOND THE END OF SAID BODY AWAY FROM AND RADIALLY OUTWARDLY FROM SAID BODY FOR SUPPORTING SAID VALVE ASSEMBLY FROM SAID INTERNAL ANNULAR SHOULDER IN ITS FULLY OPEN POSITION, SAID BODY BEING SHARPLY LONGITUDINALLY TAPERED AWAY FROM THE HEAD BETWEEN SAID LEG MEMBERS, SAID LEG MEMBERS BEING CIRCUMFERENTIALLY SPACED APART FROM EACH OTHER TO PROVIDE FLOW SPACE BETWEEN SAID MEMBERS AND EACH HAVING A LOWER SHOULDER ENGAGEABLE WITH SAID INTERNAL ANNULAR SHOULDER LIMITING THE LONGITUDINAL MOVEMENT OF SAID VALVE ASSEMBLY AWAY FROM SAID VALVE SEAT, AND AN ANNULAR FLEXIBLE SEALING SKIRT ENGAGED ON SAID VALVE BODY, SAID SKIRT HAVING AN INTERNAL ANNULAR FLARED INNER LIP CONFINED IN SAID DOVETAIL RECESS AROUND SAID BODY AND AN OUTER LIP SLOPING OUTWARDLY FROM SAID BODY ALONG THE LONGITUDINAL AXIS OF SAID BODY AWAY FROM SAID HEAD MEMBER, SAID TAPERED PORTION OF SAID BODY BETWEEN SAID LEG PORTIONS BEING DISPOSED AT A POINT ADJACENT THE FREE END OF SAID OUTER LIP OF SAID SEALING SKIRT TO PROVIDE AN UNRESTRICTED FLOW PASSAGE BETWEEN SAID LEG MEMBERS, SAID OUTER LIP BEING YIELDABLY ENGAGED WITH THE INNER WALL OF SAID FLOW PASSAGE AT ALL POSITIONS OF SAID VALVE ASSEMBLY BETWEEN SAID VALVE SEAT AND SAID ANNULAR SHOULDER AND BEING COLLAPSIBLE INWARDLY AROUND SAID VALVE BODY IN RESPONSE TO FLUID FLOW THROUGH SAID FLOW PASSAGE IN A DIRECTION FROM SAID VALVE SEAT TOWARD SAID ANNULAR SHOULDER, AND SAID SKIRT BEING ENGAGEABLE WITH THE INNER WALL OF SAID HOUSING DEFINING SAID FLOW PASSAGE, SAID VALVE SEAT, AND OVER THE LINE OF CONTACT BETWEEN SAID HEAD MEMBER AND SAID VALVE SEAT, THE ENGAGEMENT OF SAID HEAD MEMBER AND SAID VALVE SEAT RESTRAINING SAID SKIRT FROM EXTRUSION BETWEEN SAID HEAD MEMBER AND SAID VALVE SEAT WHEN SAID VALVE ASSEMBLY IS IN FULLY CLOSED POSITION.