Automatic control system for a multiple speed ratio power transmission mechanism

Claim 1

IN A CONTROL SYSTEM FOR A HYDROKINETIC TORQUE TRANSMISSION MECHANISM FOR USE IN A DRIVELINE HAVING AN ENGINE, A DRIVEN MEMBER, A FLUID PRESSURE SOURCE, FLUID PRESSURE OPERATED SERVOS, CONDUIT STRUCTURE INTERCONNECTING SAID SOURCE AND SAID SERVOS INCLUDING FLUID PRESSURE DISTRIBUTOR VALVE MEANS FOR DISTRIBUTING SELECTIVELY PRESSSURE FROM SAID SOURCE TO SAID SERVOS, A SOURCE OF A FIRST PRESSURE SIGNAL THAT IS SENSITIVE TO ENGINE TORQUE, A SOURCE OF A SECOND PRESSURE SIGNAL THAT IS SENSITIVE TO THE DRIVEN SPEED OF SAID DRIVEN MEMBER, SAID DISTRIBUTOR VALVE MEANS BEING SUBJECTED TO SAID SIGNALS AND ACTUATED THEREBY, A PRESSURE REGULATOR VALVE MEANS INCLUDING A REGULATING VALVE ELEMENT DISPOSED IN SAID CONDUIT STRUCTURE FOR MAINTAINING A REGULATED PRESSURE LEVEL IN SAID SYSTEM, A PRESSURE BOOSTER VALVE MEANS FORMING A PART OF SAID REGULATOR VALVE MEANS AND INCLUDING A MOVABLE VALVE ELEMENT, A SPRING DISPOSED BETWEEN SAID REGULATOR DRIVE ELEMENT AND SAID BOOSTER VALVE ELEMENT FOR APPLYING A CALIBRATED FORCE ON SAID REGULATOR VALVE ELEMENT, A MECHANICAL STOP ADAPTED TO BE ENGAGED BY SAID BOOSTER VALVE ELEMENT UNDER THE FORCE OF SAID SPRING, MEANS FOR DISTRIBUTING SAID FIRST PRESSURE SIGNAL TO SAID BOOSTER VALVE MEANS TO EFFECT AN INCREASE IN THE REGULATED PRESSURE LEVEL IN SAID SYSTEM WHEN ENGINE TORQUE INCREASES, THE FORCE OF SAID SPRING OVERRULING THE INFLUENCE OF SAID FIRST PRESSURE SIGNAL ON SAID BOOSTER VALVE MEANS WHEN THE ENGINE TORQUE IS