Fluid pressure regulator having a guided pressure responsive member

Claim 1

IN A FLUID PRESSURE REGULATING DEVICE, A BODY HAVING FLUID CHAMBER MEANS FORMED THEREIN, INLET AND OUTLET FLOW PASSAGES FORMED IN SAID BODY COMMUNICATING WITH SAID FLUID CHAMBER, VALVE MEANS LOCATED IN SAID INLET PASSAGE FOR CONTROLLING THE FLOW OF FLUID THEREFROM THROUGH THE FLUID CHAMBER AND OUTLET PASSAGE, SAID FLUID CHAMBER MEANS HAVING A WALL FORMED THEREIN, A LONG PRESSURE RESPONSIVE PISTON MEMBER OPERATIVELY ASSOCIATED WITH SAID VALVE MEANS AND AXIALLY SLIDABLE IN SAID CHAMBER FOR ACTUATING SAID VALVE MEANS IN RESPONSE TO CHANGES IN PRESSURE IN SAID CHAMBER AND OUTLET, FIRST COMPLEMENTARY CYLINDRICAL SLIDING SURFACES ON SAID PISTON MEMBER ADJACENT ONE END THEREOF AND THE WALL OF SAID CHAMBER, MEANS BIASING THE PISTON IN A VALVE OPENING DIRECTION, SEAL RING SEALING MEANS BETWEEN SAID FIRST COMPLEMENTARY SLIDING SURFACES, SECOND COMPLEMENTARY CYLINDRICAL SLIDING SURFACES FORMED ON SAID PISTON AT THE END THEREOF OPPOSITE FROM AND SAID BODY REMOTE FROM SAID FIRST COMPLEMENTARY SLIDING SURFACES, AND SAID FIRST AND SECOND COMPLEMENTARY SLIDING SURFACES BEING SMOOTHLY FINISHED, CLOSED-FITTING AND NON-YIELDING, WITH THEIR COMBINED AXIAL LENGTHS OF ENGAGEMENT BEING BUT A FRACTION OF THE LENGTH OF SAID PISTON TO PREVENT LATERAL MOVEMENT THEREOF WHICH MINIMIZING FRICTION BETWEEN SAID SLIDING SURFACES.