Constant volume flow control valve

Claim 1

APPARATUS FOR CONTROLLING THE FLOW OF FLUID FROM A SOURCE OF FLUID UNDER PRESSURE TO A FLUID DRIVEN DEVICE, COMPRISING: A BODY HAVING A CHAMBER THEREIN, SAID CHAMBER HAVING A FIRST END AND A SECOND END, SAID BODY ALSO HAVING AN INLET THEREIN PROVIDING COMMUNICATION BETWEEN THE SOURCE OF FLUID AND THE FIRST END OF SAID CHAMBER, AN OUTLET PASSAGEWAY EXTENDING FROM THE FIRST END OF SAID CHAMBER FOR COMMUNICATION WITH THE FLUID DRIVEN DEVICE, AND A CONNECTING PASSAGEWAY BETWEEN THE SECOND END OF SAID CHAMBER AND A PORTION OF THE OUTLET PASSAGEWAY SPACED FROM THE FIRST END OF SAID CHAMBER; A PRESSURE RESPONSIVE PISTON RECIPROCALLY DISPOSED IN SAID CHAMBER; FIRST ORIFICE MEANS CARRIED BY SAID PISTON AND ARRANGED BETWEEN SAID INLET AND THE FIRST END OF SAID CHAMBER FOR REDUCING THE PRESSURE OF THE FLUID FLOWING FROM THE INLET INTO THE FIRST END OF SAID CHAMBER, SAID FIRST ORIFICE MEANS BEING ADJUSTABLE IN RESPONSE TO MOVEMENT OF THE PISTON; SECOND ORIFICE MEANS IN SAID OUTLET PASSAGEWAY BETWEEN THE FIRST END OF SAID CHAMBER AND SAID CONNECTING PASSAGEWAY PROVIDING A PRESSURE DROP FOR FLUID FLOWING FROM THE FIRST END OF SAID CHAMBER TO THE FLUID DRIVEN DEVICE AND FOR IMPOSING A LOWER PRESSURE IN THE SECOND END OF SAID CHAMBER THROUGH SAID CONNECTING PASSAGEWAY; A ROD-LIKE MEMBER ENGAGED WITH AND EXTENDING AXIALLY THROUGH SAID PISTON, SAID MEMBER HAVING ONE END EXTENDING THROUGH SAID BODY; AND MEANS FOR EXERTING A CONSTANT FORCE ON SAID ROD-LIKE MEMBER WHEREBY SAID PISTON IS CONSTANTLY BIASED TOWARD THE FIRST END OF SAID CHAMBER; INCLUDING A SECOND CHAMBER IN THE BODY ADJACENT THE OPPOSITE END OF SAID ROD-LIKE MEMBER CONTAINING A FLUID UNDER CONSTANT PRESSURE, WHEREBY SAID PISTON MOVES TO ADJUST THE FIRST ORIFICE MEANS IN RESPONSE TO CHANGES IN THE PRESSURE OF THE FLUID AT SAID CONNECTING PASSAGEWAY TO MAINTAIN A CONSTANT PRESSURE DROP THROUGH SAID SECOND ORIFICE MEANS AND A CONSTANT FLOW OF FLUID TO THE FLUID DRIVEN DEVICE.