Butterfly valve

Claim 1

A BUTTERFLY VALVE FOR FITTING BETWEEN SPACED APART FLANGES EACH HAVING A FLANGE FACE, SAID VALVE COMPRISING: A BODY MEMBER HAVING PARALLELED FLANGE ENGAGING ENDS AND AN AXIAL BORE THERETHROUGH PERPENDICULAR THE ENDS; A TUBULAR RIGID REINFORCING MEMBER DEFINED IN PART BY EXTERIORLY CONVERGING TAPERED ENDS; A TUBULAR RESILIENT LINER FULLY ENCOMPASSING SAID REINFORCING MEMBER, SAID LINER MEMBER BEING POSITIONED IN SAID BODY MEMBER AXIAL BORE, THE EXTERIOR CIRCUMFERENTIAL SURFACE THEREOF ENGAGING THE INTERIOR CIRCUMFERENTIAL SURFACE OF SAID BODY MEMBER AXIAL BORE, SAID TUBULAR LINER PROVIDING AN AXIAL FLUID PASSAGEWAY THERETHROUGH, SAID LINER BEING OF A LENGTH SUBSTANTIALLY EQUAL TO THE LENGTH OF SAID AXIAL BORE IN SAID BODY AND INCLUDING A CIRCUMFERENTIAL INTEGRAL ARCUATE INCREASED LENGTH FLANGE ENGAGING PORTION AT EACH AND ALIGNED WITH AND SPACED FROM SAID TAPERED ENDS OF SAID REINFORCING MEMBER WHEREBY AS THE ENDS OF SAID RESILIENT MEMBER ARE ENGAGED BY THE FLANGE FACES THE FLANGE ENGAGING PORTIONS THEREOF ARE DEFORMED AGAINST THE SAID TAPERED ENDS OF THE REINFORCING MEMBER CAUSING INCREASED RADIAL OUTWARD SEALING CONTACT PRESSURE OF THE RESILIENT LINER AGAINST THE INTERIOR CIRCUMFERENTIAL SURFACE OF THE AXIAL BORE OF SAID BODY MEMBER; A DISC MEMBER PIVOTALLY SUPPORTED IN SAID FLUID PASSAGEWAY IN SAID RESILIENT LINER, SAID DISC IN PART DEFINED BY A PERIPHERAL LINER ENGAGING SEATING SURFACE, SAID DISC SEATING SURFACE SEALABLY ENGAGING SAID RESILIENT LINER WHEN THE DISC IS IN CLOSED POSITION; AND MEANS OF PIVOTING SAID DISC BETWEEN OPEN AND CLOSED POSITION.