Electro-hydraulic servo power control system

Claim 1

AN HYDRAULIC SERVO POWER SYSTEM COMPRISING, IN COMBINATION: A REVERSIBLE ACTUATOR HAVING MOVABLE PRESSURE RESPONSIVE MEANS AND RESPECTIVE POWER CHAMBERS ARRANGED FOR OPPOSED FLUID PRESSURE ACTION AGAINST SAID PRESSURE RESPONSIVE MEANS; A SERVO VALVE HAVING OPPOSED CONTROL ORIFICES, A SECOND MOVABLE ELEMENT BETWEEN SAID ORIFICES, AND A REMOTELY CONTROLLED SERVOMOTOR ACTING UPON SAID SECOND MOVABLE ELEMENT TO VARY THE RESTRICTION OF SAID ORIFICES SOLELY IN RESPONSE TO COMMAND SIGNALS TRANSMITTED THERETO; MULTIPLE PUMP MEANS HAVING TWO OUTLETS INDEPENDENTLY RECEIVING PRESSURE FLUID FLOWS PUMPED BY RESPECTIVE PUMP ELEMENTS; AND MUTUALLY ISOLATED FLUID DELIVERY LINES EACH CONNECTING A RESPECTIVE PUMP OUTLET TO A RESPECTIVE POWER CHAMBER OF SAID ACTUATOR AND, IN PARALLEL, TO A RESPECTIVE CONTROL ORIFICE OF SAID SERVO VALVE, WHEREBY DISPLACEMENT OF SAID SECOND MOVABLE ELEMENT TOWARD ONE OF SAID CONTROL ORIFICES AND AWAY FROM THE OTHER WILL RESTRICT ESCAPE OF FLUID FROM SAID ONE CONTROL ORIFICE AND CORRESPONDINGLY WILL INCREASE THE FLUID PRESSURE IN THE POWER CHAMBER CONNECTED THERETO, WHILE PERMITTING INCREASED FLOW FROM SAID OTHER CONTROL ORIFICE AND RELIEVING PRESSURE IN THE OTHER POWER CHAMBER SO AS TO EFFECT MOVEMENT OF THE ACTUATOR TOWARD SAID OTHER POWER CHAMBER, UTILIZING THE FULL PRESSURE AND FLOW DELIVERED FROM A RESPECTIVE PUMP OUTLET, SAID SYSTEM HAVING A POWER INPUT REQUIREMENT LESS THAN HALF THAT OF AN HYDRAULIC SERVO POWER SYSTEM OF EQUAL OUTPUT CAPACITY HAVING A COMMON PATH OF FLOW FROM PUMP OUTLET TO BOTH POWER CHAMBERS OF A REVERSIBLE ACTUATOR.