Cartridge valves

Claim 1

IN A VALVE, (A) A HOUSING PROVIDED WITH AN INLET, AN OUTLET, AND A FLUID PORT, (B) SAID HOUSING BEING PROVIDED WITH AN AXIALLY EXTENDING BORE, (C) A PISTON AXIALLY SLIDABLY CARRIED IN SAID BORE, (D) A SPRING CARRIED IN SAID HOUSING URGING SAID PISTON IN ONE AXIAL DIRECTION, (E) A CONTROL OUTLET PROVIDED IN SAID HOUSING AND PASSAGES CONNECTING SAID CONTROL OUTLET WITH SAID INLET, (F) SAID CONTROL OUTLET BEING ADAPTED TO FOR CONNECTION WITH A PILOT VALVE OPERABLE TO SELECTIVELY VARY THE FLOW THROUGH SAID CONTROL OUTLET, (G) AT LEAST ONE OF SAID PASSAGES BEING RESTRICTED WHEREBY TO CREATE A PRESSURE DIFFERENTIAL WHICH VARIES DEPENDING UPON THE AMOUNT OF FLOW ALLOWED THROUGH SAID CONTROL OUTLET, (H) MEANS TO TRANSMIT SUCH PRESSURE DIFFERENTIAL TO SAID PISTON AND TO URGE AXIAL MOVEMENT OF SAID PISTON IN OPPOSITION TO SAID SPRING UPON AN INCREASE IN SAID PRESSURE DIFFERENTIAL, (I) SAID PISTON BEING PROVIDED WITH A FIRST VALVE MEANS OPENING COMMUNICATION BETWEEN SAID INLET AND SAID PORT AT ONE OPERATING POSITION THEREOF AND CLOSING COMMUNICATION BETWEEN SAID INLET AND SAID PORT AND OPENING COMMUNICATION BETWEEN SAID PORT AND SAID OUTLET AT ANOTHER OPERATING POSITION THEREOF, AND (J) A SECOND VALVE MEANS CARRIED IN SAID HOUSING AND BEING SELECTIVELY OPERABLE INDEPENDENTLY OF SAID FIRST VALVE MEANS TO CLOSE COMMUNICATION BETWEEN SAID PORT AND SAID OUTLET AT EITHER OPERATING POSITION OF SAID PISTON, (K) SAID SECOND VALVE MEANS COMPRISING A MOVABLE PISTON DISPOSED WITHIN SAID BORE AT ONE END OF SAID FIRST MENTIONED PISTON, MEANS FOR PROVIDING FLUID PRESSURE TO ONE SIDE OF SAID SECOND MENTIONED PISTON TO URGE SAME TOWARD A POSITION CLOSING FLUID FLOW FROM SAID PORT THROUGH SAID OUTLET AND MEANS FOR SELECTIVELY EXHAUSTING SAID FLUID PRESSURE TO MOVE SAID LAST MENTIONED PISTON TO A POSITION CLOSING FLUID FLOW FROM SAID PORT THROUGH SAID OUTLET.