Fluid control valves

Claim 1

IN A CIRCUIT OF FLUID CONTROL VALVES HAVING A PAIR OF PARALLEL FLUID INLET PASSAGES AND A FLUID EXHAUST PASSAGE THE IMPROVEMENT COMPRISING AN INLET SECTION COMPRISING AN INLET PORT CONTINUOUSLY CONNECTING THE PARALLEL INLET PASSAGES TO A SOURCE OF PRESSURE FLUID AND CHECK VALVE MEANS CONNECTING THE EXHAUST PASSAGE TO THE TWO FLUID INLET PASSAGES AND ADAPTED TO PERMIT FLOW FROM THE EXHAUST PASSAGE TO THE INLET PASSAGES WHEN THE PRESSURE IN THE EXHAUST EXCEEDS THAT IN THE INLET PASSAGES AND AN OUTLET SECTION COMPRISING A HOUSING, A BORE IN SAID HOUSING, A VALVE ELEMENT SLIDABLE IN SAID BORE, RESILIENT MEANS NORMALLY BIASING THE VALVE TOWARD ONE END OF SAID BORE, A FIRST CHAMBER ADJACENT THE RESILIENT MEANS INTERSECTING THE BORE AND COMMUNICATING WITH THE EXHAUST PASSAGE OF THE FLUID CONTROL VALVES, AN OUTLET CHAMBER INTERSECTING THE BORE AND CONNECTED TO AN EXHAUST PORT AT THE EXTERIOR OF THE HOUSING, SAID CHAMBER COMMUNICATING THROUGH THE BORE WITH THE FIRST CHAMBER WHEN THE VALVE ELEMENT IS MOVED AGAINST THE RESILIENT BIASING MEANS, AND A HIGH PRESSURE CHAMBER RECEIVING FLUID FROM THE PARALLEL FLUID PASSAGES OF PRECEDING VALVES, WHEREBY THE VALVE ELEMENT IS MOVED TO OVERCOME THE BIASING EFFECT OF THE RESILIENT MEANS WHEN THE PRESSURE OF INLET FLUID IS AT A PRESELECTED LEVEL PERMITTING EXHAUST FLUID TO FLOW THROUGH THE FIRST CHAMBER, THE BORE AND THE OUTLET CHAMBER TO BE DISCHARGED FROM THE VALVE AND WHEN THE PRESSURE IS BELOW THE PRESELECTED LEVEL CAUSING VALVE ELEMENT TO CLOSE THE BORE AND FORCE THE EXHAUST FLUID THROUGH THE INLET SECTION CHECK TO SUPPLEMENT THE INPUT FLUID.