Multiple speed ratio power transmission control mechanism with pneumatically operated ratio controllers

Claim 1

A CONTROL SYSTEM FOR AN AUTOMATIC POWER TRANSMISSION MECHANISM HAVING FLUID PRESSURE OPERATED SERVOS CAPABLE OF ESTABLISHING EACH OF SEVERAL TORQUE DELIVERY PATHS BETWEEN AN INTERNAL COMBUSTION ENGINE AND A DRIVEN MEMBER, SAID ENGINE HAVING AN AIR-FUEL MIXTURE INTAKE MANIFOLD, A FLUID PRESSURE SOURCE, CONDUIT STRUCTURE CONNECTING SAID PRESSURE SOURCE AND SAID SERVOS, FLUIKD PRESSURE DISTRIBUTOR VALVE MEANS SITUATED IN AND PARTLY DEFINING SAID CONDUIT STRUCTURE FOR CONTROLLING DISTRIBUTION OF PRESSURE FROM SAID SOURCE TO EACH OF SAID SERVOS TO EFFECT SPEED RATIO CHANGES, THROTTLE VALVE MEANS FOR PRODUCING A FLUID PRESSURE SIGNAL THAT IS PROPORTIONAL IN MAGNITUDE TO ENGINE INTAKE MANIFOLD PRESSURE, SAID THROTTLE VALVE MEANS BEING IN FLUID COMMUNICATION WITH SAID DISTRIBUTOR VALVE MEANS WHEREBY THE LATTER IS ACTUATED IN RESPONSE TO CHANGES IN THE MAGNITUDE OF SAID PRESSURE SIGNAL, A MANIFOLD PRESSURE PASSAGE INTERCONNECTING THE ENGINE INTAKE MANIFOLD AND SAID THROTTLE VALVE MEANS, A SECONDARY VALVE MEANS SITUATED IN AND PARTLY DEFINING SAID MANIFOLD PRESSURE PASSAGE INCLUDING A MOVABLE VALVE ELEMENT THAT BLOCKS SAID MANIFOLD PRESSURE PASSAGE WHEN IT ASSUMES ONE POSITION AND ACCOMMODATES PRESSURE DISTRIBUTION THROUGH SAID MANIFOLD PRESSURE PASSAGE WHEN IT ASSUMES A SECOND POSITION, AND A VALVE OPERATOR MEANS IN COMMUNICATION WITH SAID ENGINE INTAKE MANIFOLD AND RESPONSIVE TO CHANGES IN THE MAGNITUDE OF THE MANIFOLD PRESSURE FOR MOVING SAID MOVABLE VALVE ELEMENT TO SAID SECOND POSITION WHEN THE MANIFOLD PRESSURE IS LESS THAN A PREDETERMINED VALUE AND FOR EFFECTING MOVEMENT OF SAID MOVABLE VALVE ELEMENT TO SAID ONE POSITION WHEN THE MANIFOLD PRESSURE IS GREATER THAN SAID PREDETERMINED VALUE.