Metal clad soft seat valve closure assembly

Claim 1

A HIGH PRESSURE METERING VALVE FOR FLUIDS COMPRISING A VALVE BODY FORMED WITH A CYLINDRICAL SPINDLE OPENING INCLUDING A LOWER CYLINDRICAL END TERMINATING IN A BOTTOM, A FIRST PASSAGEWAY FOR FLUID COAXIAL WITH SAID SPINDLE OPENING AND COMMUNICATING WITH SAID BOTTOM, A SECOND PASSAGEWAY FOR FLUID COMMUNICATING WITH SAID LOWER END OF SAID SPINDLE OPENING ABOVE THE BOTTOM THEREOF, A VALVE DISC HAVING A CIRCULAR BORE DEFINING AN INTERIOR SURFACE IN SAID DISC, SAID DISC BEING COMPOSED OF COLD FLOWING PLASTIC AND SAID DISC BEING POSITIONED WITHIN SAID LOWER END OF SAID SPINDLE OPENING, METAL ENCLOSING MEANS FOR SAID PLASTIC VALVE DISC ENGAGING THE ENTIRE EXTERIOR SURFACE THEREOF, A PRIMARY SPINDLE BARREL SECURED WITHIN SAID SPINDLE OPENING AND HAVING ITS LOWER END TERMINATING ABOVE SAID SECOND PASSAGEWAY, A SECONDARY SPINDLE BARREL POSITIONED WITHIN SAID PRIMARY SPINDLE BARREL AND EXTENDING BELOW THE LOWER END THEREOF, SAID SECONDARY SPINDLE BARREL HAVING A LOWER CYLINDRICAL PORTION FITTED WITHIN THE LOWER END OF SAID SPINDLE OPENING, SAID LOWER CYLINDRICAL PORTION BEING FORMED WITH PORTS POSITIONED ABOVE THE LOWER END OF SAID SECONDARY SPINDLE BARREL, SAID PORTS COMMUNICATING BETWEEN THE INTERIOR OF SAID SECONDARY SPINDLE BARREL AND SAID SECOND PASSAGEWAY FOR FLUID, AND A VALVE STEM LONGITUDINALLY MOVABLE WITHIN SAID SPINDLE BARRELS AND HAVING A PISTON VALVE PORTION AND A TAPERED METERING POINT, SAID TAPERED METERING POINT BEING ADAPTED TO SEALINGLY ENGAGE THE INTERIOR SURFACE OF SAID VALVE DISC, SAID PISTON VALVE PORTION OF SAID VALVE STEM OBSTRUCTING SAID PORTS TO PERMIT SLOW METERED PASSAGE OF FLUID THROUGH SAID VALVE WHILE SAID PORTS ARE OBSTRUCTED AND SAID PORTS BEING POSITIONED SUFFICIENTLY ABOVE THE LOWER END OF SAID SECONDARY SPINDLE BARREL SO THAT SAID METERING POINT IS WELL AWAY FROM THE COLD FLOWING PLASTIC OF SAID VALVE DISC BEFORE SAID PISTON VALVE PORTION IS MOVED SUFFICIENTLY TO START OPENING SAID PORTS.