Swivel ring valve

Claim 1

A CONTROL VALVE COMPRISING A HOUSING, SAID HOUSING HAVING AN INLET, OUTLET AND RELIEF PORTS INTEGRALLY FORMED THEREIN, A CONNECTING PASSAGE BETWEEN SAID INLET AND OUTLET PORTS DEFINING A VENTURI THROAT OVER A PORTION OF A LENGTH THEREOF, A VALVE SEAT POSITIONED WITHIN SAID PASSAGE, A ROTATABLE VALVE STEM, MEANS FOR ROTATING THE VALVE STEM SECURED TO THE UPPER PORTION THEREOF, A CONICAL SHAPED SURFACE FORMED ON THE OTHER END PORTION OF SAID VALVE STEM, AN ANNULAR GROOVE RECESSED IN THE LOWER PORTION OF THE VALVE STEM ADJACENT TO SAID CONICAL SURFACE, SAID GROOVE HAVING A RETAINING LIP IN JUXTAPOSITION WITH SAID CONICAL SURFACE, SAID GROOVE HAVING A SIDE WALL TAPERING INWARDLY, RELATIVE TO THE CENTER LINE OF THE VALVE STEM AND AN UPPER WALL ANGLING UPWARDLY RELATIVE TO A HORIZONTAL PLANE, AND A FLEXIBLE PLASTIC SEALING MEMBER, SAID SEALING MEMBER SWIVELLY DISPOSED IN SAID GROOVE TO PRESENT A SUBSTANTIALLY DIFFERENT SURFACE AREA TO ENGAGE THE VALVE SEAT, SAID FLEXIBLE PLASTIC SEALING MEMBER CONSISTS OF A CIRCULAR RING OF RESILIENT PLASTIC OF LOW CO-EFFICIENT OF FRICTION WHICH IS SUBSTANTIALLY QUINQUELATERAL IN CROSS SECTION AND HAS AN UPPER CONTOURED SEALING SURFACE WHICH ROTATABLY ENGAGES THE UPPER WALL OF SAID GROOVE IN SEALING RELATIONSHIP AND A SIDE CONTOURED SEALING SURFACE WHICH ENGAGES THE VALVE SEAT AND SIDE WALL OF THE GROOVE TO EFFECT A LEAK-PROOF CLOSURE BETWEEN THE INLET AND OUTLET PORTS WHEN THE VALVE IS IN AN EXTREME CLOSED POSITION, STEM SURFACES ABOVE AND BELOW THE GROOVE MAINTAINING A SPACED RELATIONSHIP WITH THE VALVE SEAT WHEREBY SAID RING IS RETAINED FROM FLOW BETWEEN THE VALVE SEAT AND SAID UPPER WALL AS AN AXIAL FORCE IS APPLIED THERETO WHEREBY A PERFECT LEAK-PROOF SEAL IS ATTAINED WHEN THE VALVE STEM IS IN THE EXTREME CLOSED POSITION.