Multi-function control valve apparatus

Claim 1

MULTIFUNCTION FLUID VALVE APPARATUS AND FLUID PRESSURE RECIPROCABLE ACTUATING MEANS COMPRISING: A MAIN CONTROL VALVE CASING PROVIDED WITH A LONGITUDINAL BORE FORMED WITH A FLUID SENSING CHAMBER, A VALVE STEM AXIALLY RECIPROCABLE IN SAID BORE AND CARRYING A SENSING PISTON PARTIONING SID CHAMBER INTO FIRST AND SECOND SIDES, CONTROL ORIFICE MEANS INTERCOMMUNICATING SAID FIRST AND SECOND SIDES, SAID BORE FURTHER BEING FORMED WITH A METERING FLUID CHAMBER HAVING A MEANS FOR FLUID INTERCOMMUNICATION WITH SAID FIRST SIDE OF THE SENSING CHAMBER, FLUID PRESSURE INLET AND OUTLET MEANS DISPOSED RESPECTIVELY ONE OF EACH SIDE OF SAID METERING FLUID CHAMBER, A PAIR OF METERING VALVE MEANS CARRIED BY SAID STEM AND DISPOSED ONE FOR METERING PRESSURE INLET FLOW INTO SAID METERING CHAMBER AND THE OTHER FOR METERING FLUID FLOW FROM SAID METERING CHAMBER TO SAID FLUID OUTLET MEANS, MEANS FOR MECHANICALLY RECIPROCATING SAID VALVE STEM IN ITS AXIAL DIRECTION, FLUID-PRESSURE RECIPROCABLE ACTUATING MEANS HAVING A FLUID PRESSURE INLET AND ALSO BEING IN FLUID COMMUNICATION WITH SAID SECOND SIDE OF THE SENSING CHAMBER, AND CONTROLLABLE FLUID PRESSURE MEANS FOR SELECTIVELY RECIPROCATING SAID VALVE STEM IN ONE AXIAL DIRECTION OR THE OTHER, SAID CONTROLABLE FLUID PRESSURE ACTING ON THE ENDS OF SAID STEM IS COUNTERACTING OPPOSITION TO PRESSURE DIFFERENTIALS ACROSS AND SENSING PISTON WHEREBY A PRESSURE BALANCE ACROSS SAID PISTON IS OBTAINED FOR PRODUCING A CONTROLLED AND METERED FLOW RATE TO AND FROM SAID ACTUATOR MEANS, AND SAID MECHANICAL RECIPROCATIONS OF THE STEM BEING RESPONSIVE TO PREDETERMINED DISPOSITIONS OF THE ACTUATOR MEANS RECIPROCATIONS FOR RESTRICTING AND STOPPING SAID PRESSURE INLET AND OUTLET FLOW OF SAID METERING CHAMBER.