Dual input servo control mechanism

Claim 1

A SERVO CONTROL MECHANISM HAVING COOPERATING PISTON AND CYLINDER ELEMENTS, A PISTON ROD CONNECTING SAID PISTON ELEMENT TO FIXED STRUCTURE AND MEANS CONNECTING THE CYLINDER TO MOVEABLE STRUCTURE, VALVE MEANS, SAID VALVE MEANS COMPRISING A BODY, SAID BODY BEING CONNECTED TO THE CYLINDER ELEMENT, A SLEEVE MOUNTED FOR RECIPROCABLE MOVEMENT IN SAID BODY, A RETURN, A SOURCE OF PRESSURE, RELATIVE MOVEMENT OF SAID SLEEVE AND PILOT VALVE FROM A NULL POSITION CONNECTING ONE END OF SAID CYLINDER ELEMENT TO SAID SOURCE OF PRESSURE AND THE OTHER END OF SAID CYLINDER TO SAID RETURN, ELECTRICAL MEANS FOR ACTUATING SAID SLEEVE, MECHANICAL MEANS FOR ACTUATING SAID PILOT VALVE, A CYLINDER EXTENSION EXTENDING FROM THE END OF SAID CYLINDER ELEMENT AROUND THE PISTON ROD CONNECTING SAID PISTON ELEMENT TO FIXED STRUCTURE, AND ANNULUS IN SAID EXTENSION POSITIONED COAXIALLY WITH THE PISTON ROD, AN ANNULAR MEMBER SLIDEABLY MOUNTED IN SAID ANNULUS, SAID MECHANICAL MEANS HAVING AN ACTUATING CYLINDER, SAID ACTUATING CYLINDER HAVING ONE END SLIDEABLY MOUNTED ON SAID CYLINDRICAL EXTENSION, MEANS LOCKING SAID ACTUATING CYLINDER TO SAID CYLINDER ELEMENT FOR DIRECT MOVEMENT WHEN SAID SOURCE OF PRESSURE IS REDUCED A PREDETERMINDED VALUE, SAID LOCKING MEANS COMPRISING A FIRST ANNULAR GROOVE AROUND THE INNER FACE OF THE END OF THE ACTUATING CYLINDER SLIDEABLY MOUNTED ON SAID CYLINDRICAL EXTENSION, A CAM FOLLOWER POSITIONED IN AN OPENING IN THE EXTENSION SO THAT IT IS RADIALLY MOVEABLY THEREIN, A SECOND ANNULAR GROOVE AROUND THE LOWER PERIPHERY OF SAID ANNULAR MEMBER, SAID ANNULAR MEMBER BEING HELD IN POSITION BY SAID SOURCE OF PRESSURE PLACING ITS SECOND ANNULAR GROOVE IN LINE WITH SAID CAM FOLLOWER, SAID ANNULAR MEMBER BEING BIASED IN ITS OPPOSITE DIRECTION WHEN SAID PRESSURE HAS BEEN REDUCED A PREDETERMINED AMOUNT, A CAM ON SAID ANNULAR MEMBER LIMITING TO MOVE THE CAM FOLLOWER OUTWARDLY WHEN THE ANNULAR MEMBER IS BEING BIASED UPWARDLY, SAID CAM FOLLOWER MOVING INTO SAID FIRST ANNULAR GROOVE WHEN THEY ARE LINED UP AND THERE IS A REDUCTION OF PRESSURE BELOW A PREDETERMINED VALUE.