Protected ball valve seal

Claim 1

A SEALED BALL VALVE COMPRISING A HOUSING HAVING AN INLET, AN OUTLET, AND A FLOW PATH THERETHROUGH COMMUNICATING SAID INLET AND SAID OUTLET; A VALVE BALL HAVING A FLOW PASSAGE THERETHROUGH AND ROTATABLY MOUNTED IN SAID HOUSING ABOUT AN AXIS TRANSVERSE TO SAID FLOW PATH; SAID HOUSING HAVING AN ABUTMENT THEREIN ADJACENT THE INLET, SAID ABUTMENT BEING SPACED FROM SAID BALL; A VALVE SEAL COMPRISING A FLAT DEFORMABLE ANNULUS HAVING AN INNER SUBSTANTIALLY CYLINDRICAL SURFACE OF A DIAMETER GREATER THAN THAT OF SAID FLOW PASSAGE AND SUBSTANTIALLY SMALLER THAN THAT OF SAID BALL WITH SAID CYLINDRICAL SURFACE BEING SUBJECTED TO VARIABLE PRESSURES RESPONSIVE TO TURBULENT FLOW PAST SAID CYLINDRICAL SURFACE, SAID ANNULUS BEING MOUNTED SO THAT AN INNER EDGE THEREOF BEARS AGAINST THE UPSTREAM SIDE OF SAID BALL; A FLAT METAL SUPPORT DISC INTERPOSED BETWEEN SAID ANNULUS AND SAID ABUTMENT IN SAID HOUSING AND EXTENDING ON THE DOWNSTREAM SIDE OF SAID ANNULUS TOWARD SAID BALL BUT WITH RUNNING CLEARANCE THEREBETWEEN; A FLAT METAL PROTECTOR DISC DISPOSED AGAINST THE UPSTREAM SIDE OF SAID ANNULUS AND HAVING AN INTERNAL FLANGE EXTENDING DOWNSTREAM AND OVERLYING A SUBSTANTIAL PART OF SAID INNER CYLINDRICAL SURFACE TO PROTECT SAID SURFACE FROM THE EFFECTS OF SAID TURBULENT FLOW; MEANS FOR HOLDING SAID PROTECTOR DISCS AND SAID ANNULUS IN SAID HOUSING IN SIDE-BY-SIDE ABUTTING RELATIONSHIP AGAINST THE ABUTMENT THEREIN; AND MEANS CLAMPINGLY SECURING SAID HOLDING MEANS TO SAID HOUSING TO FLEX SAID ANNULUS INTO EDGE SEALING RELATIONSHIP WITH THE UPSTREAM SIDE OF SAID BALL.