Fluid power apparatus

Claim 1

IN A FLUID POWER ACTUATED STABILIZING SYSTEM FOR A VEHICLE HAVING RESPECTIVE SPRUNG AND UNSPRUNG MASSES AND A FLUID POWER ACTUATOR WITH AN EXPANSIBLE CHAMBER COUPLED BETWEEN SAID MASSES, A SENSING AND CONTROL SYSTEM FOR CONTROLLING THE FLOW OF FLUID IN AND OUT OF SAID EXPANSIBLE CHAMBER, SAID SYSTEM COMPRISING AN INERTIA SENSING DEVICE, A PILOT PRESSURE CIRCUIT HAVING A PILOT VALVE RESPONSIVE TO SAID INERTIA SENSING DEVICE FOR DETERMINING THE PRESSURE OF SAID PILOT CIRCUIT, A BODY HAVING A CYLINDRICAL BORE WITH ONE END AXIALLY POINTING IN A DIRECTION A AND THE OTHER END POINTING IN AN OPPOSITE DIRECTION B, SAID BODY HAVING A SECOND CHAMBER, THE B END OF THE BORE OPENING INTO THE SECOND CHAMBER, THE B END OF THE BORE OPENING INTO THE SECOND CHAMBER, CYLINDRICAL VALVE MEMBERS C AND D ARRANGED IN TANDEM WITHIN SAID BORE FOR AXIAL SLIDABLE MOVEMENT THEREIN, VALVE MEMBER D BEING BETWEEN MEMBER C AND THE SECOND CHAMBER, VALVE MEMBER D HAVING A PASSAGE EXTENDING AXIALLY THERETHROUGH, VALVE MEMBER D HAVING CLOSURE MEANS, SAID BODY HAVING A FLUID PRESSURE SUPPLY PORT WHICH IS OPEN TO SAID SECOND CHAMBER WHEN MEMBER D IS AXIALLY MOVED IN THE DIRECTION B AND WHICH IS BLOCKED FROM THAT CHAMBER BY SAID CLOSURE MEANS IN RESPONSE TO MOVEMENT OF MEMBER D IN THE A DIRECTION, SAID BODY HAVING AN EXHAUST PORT OPEN TO SAID BORE AT THE JUNCTURE OF THE ADJACENT ENDS OF MEMBERS C AND D, SAID ADJACENT ENDS RESPECTIVELY BEING A SEAT AND A CLOSURE FORMING AN EXHAUST VALVE WHICH IN RESPONSE TO AXIAL RELATIVE MOVEMENT APART OF MEMBERS C AND D OPENS THE EXHAUST PORT TO SAID PASSAGE IN MEMBER D, AND IN RESPONSE TO RELATIVE MOVEMENT TOGETHER OF MEMBERS C AND D BLOCKS THE EXHAUST PORT FROM SAID PASSAGE IN MEMBER D, FLUID PASSAGE MEANS CONNECTING THE SECOND CHAMBER WITH THE EXPANSIBLE CHAMBER OF THE ACTUATOR, MEANS FOR BIASING MEMBER C IN THE DIRECTION A, MEANS FOR BIASING MEMBER D IN THE DIRECTION A, AND MEANS FOR SUBJECTING MEMBER C TO THE FLUID PRESSURE OF SAID PILOT CIRCUIT TO URGE MEMBER C IN THE DIRECTION B, THE LATTER MEANS AT A PARTICULAR PRESSURE FORCING MEMBER C INTO ENGAGEMENT WITH MEMBER D TO CLOSE THE EXHAUST VALVE AND AT GREATER PRESSURE CAUSING MEMBER C TO MOVE MEMBER D IN THE DIRECTION B TO OPEN THE SUPPLY PORT TO THE SECOND CHAMBER.