Trunnion mounted ball valve having lost motion and positive reduction actuating means

Claim 1

A TRUNNION MOUNTED BALL VALVE, COMPRISING A VALVE BODY HAVING A CENTRAL CAVITY, A GENERALLY CYLINDRICAL INLET PORT COMMUNICATING WITH ONE SIDE OF SAID CAVITY, AN OUTLET PORT COMMUNICATING WITH THE OTHER SIDE OF SAID CAVITY, AN ANNULAR SEAT SEAL MOUNTED IN SAID INLET PORT AND BEING AXIALLY SLIDABLE THEREIN, SAID SEAT SEAL HAVING A SEALING FACE CONCENTRIC WITH SAID INLET PORT AND PROJECTING INTO SAID CAVITY, A BALL ELEMENT IN SAID CAVITY, SAID BALL HAVING UPPER AND LOWER AXIALLY ALIGNED TRUNNIONS, BEARING MEANS IN SAID VALVE BODY FOR RECEIVING SAID LOWER TRUNNION, SAID BALL HAVING A FLUID PASSAGE ARRANGED IN ONE ROTATIONAL POSITION OF SAID BALL TO PROVIDE FLUID COMMUNICATION BETWEEN SAID PORTS AND IN ANOTHER ROTATIONAL POSITION OF SAID BALL TO BE OUT OF FLUID COMMUNICATION WITH SAID INLET PORT, A SPRING ELEMENT MOUNTED IN SAID INLET PORT AND ARRANGED TO URGE SAID SEAT SEAL TO MOVE AXIALLY TOWARD SAID BALL WHEREBY SAID SEALING FACE COMES INTO SEALING CONTACT WITH A SEALING SURFACE OF SAID BALL WHEN SAID BALL IS IN SAID OTHER ROTATIONAL POSITION THEREOF, DRIVING MEANS TO ROTATE SAID BALL BETWEEN SAID POSITIONS THEREOF, AND CAM MEANS SEPARATE FROM AN OPERATED BY SAID DRIVING MEANS AND ARRANGED TO CONTACT SAID SEAT SEAL AND TO MOVE SAID SEAT SEAL OUT OF CONTACT WITH SAID BALL WHEN SAID DRIVING MEANS IS ACTUATED TO MOVE SAID BALL FROM SAID SECOND TOWARD SAID FIRST POSITION THEREOF AND TO RETAIN SAID SEAT SEAL OUT OF CONTACT WITH SAID BALL EXCEPT WHEN SAID BALL APPROACHES SAID SECOND POSITION THEREOF WHEN BEING ROTATED TOWARD SAID SECOND POSITION THEREOF, SAID DRIVING MEANS AFFORDING LOST MOTION IN ROTATING SAID BALL WHEREBY SAID CAM MEANS MOVES SAID SEAT SEAL OUT OF CONTACT WITH SAID BALL BEFORE SAID DRIVING MEANS COMMENCES TO ROTATE SAID BALL FROM SAID SECOND POSITION THEREOF.