Automatic variable speed transmission, more particularly for motor vehicles

Claim 1

AUTOMATIC VARIABLE SPEED TRANSMISSION MORE PARTICULARLY FOR MOTOR VEHICLES, OF THE TYPE IN WHICH THE DRIVING SHAFT IS COUPLED WITH THE INTERNAL COMBUSTION ENGINE BY AN AUTOMATIC CLUTCH, THE DRIVEN SHAFT BEING CONNECTED WITH THE STUB AXLES OF THE WHEELS THROUGH A DIFFERENTIAL GEAR, SAID TRANSMISSION COMPRISING TWO EXPANSIBLE PULLEYS, NAMELY A DRIVING AND A DRIVEN PULLEY, RESPECTIVELY, INTERCONNECTED BY A V-BELT, EACH PULLEY COMPRISING A FLANGE FIXED TO ITS RESPECTIVE SHAFT AND A MOVABLE FLANGE CAPABLE OF AXIAL DISPLACEMENT ON ITS RESPECTIVE SHAFT; MEANS FOR CONTROLLING THE AXIAL DISPLACEMENTS OF THE MOVABLE FLANGE OF THE DRIVING PULLEY COMPRISING A HYDRAULIC ACTUATOR HAVING ITS MOVABLE PORTION OPERATIVELY CONNECTED WITH SAID MOVABLE FLANGE AND A VALVE HYDRAULICALLY CONNECTED WITH SAID ACTUATOR AND WITH FEED AND DISCHARGE CONDUITS FOR A PRESSURE FLUID, SAID VALVE COMPRISING A BODY, A FIRST AND A SECOND VALVE MEMBER WHICH ARE RELATIVELY MOVABLE AND AXIALLY SLIDABLE IN THE BODY OF THE VALVE, SPRING ARRANGED BETWEEN SAID VALVE BODY AND EACH OF SAID VALVE MEMBERS IN ORDER TO MAINTAIN THEIR RESPECTIVE MEMBER IN AN INOPERATIVE POSITION, IN WHICH THE DISCHARGE CONDUIT CONNECTS WITH THE HYDRAULIC ACTUATOR, THE FIRST VALVE MEMBER BEING AXIALLY DISPLACEABLE BY A CENTRIFUGAL GOVERNOR ROTATED BY THE DRIVING SHAFT, THE SECOND VALVE MEMBER BEING AXIALLY DISPLACEABLE BY THE DEFORMATION OF A SEALED DEFORMABLE CHAMBER PNEUMATICALLY CONNECTED WITH AN INDUCTION CONDUIT OF THE ENGINE AND MEANS FOR CONTROLLING THE AXIAL DISPLACEMENTS OF THE MOVABLE FLANGE OF THE DRIVEN PULLEY COMPRISING SPRING MEANS ARRANGED BETWEEN THE DRIVEN SHAFT AND THE MOVABLE FLANGE OF THE DRIVEN PULLEY AND URGING SAID MOVABLE FLANGE TOWARDS THE FIXED FLANGE, A CENTRIFUGAL GOVERNOR ROTATED BY THE DRIVEN SHAFT AND OPERATIVELY CONNECTED WITH THE MOVABLE FLANGE OF THE DRIVEN PULLEY AND A DEFORMABLE SEALED CHAMBER PNEUMATICALLY CONNECTED WITH THE INDUCTION CONDUIT OF THE ENGINE AND HAVING A FIXED WALL FAST WITH THE DRIVEN SHAFT AND A MOVABLE WALL CONNECTED WITH THE MOVABLE FLANGE OF THE DRIVEN PULLEY, THE ACTION OF THE LAST MENTIONED CENTRIFUGAL GOVERNOR ON RISE IN NUMBER OF REVOLUTIONS OF THE DRIVEN SHAFT, AND THE ACTION DUE TO AIR SUCTION FROM THE LAST MENTIONED CHAMBER BEING OPPOSITELY DIRECTED TO THE ACTION OF THE SPRINGS URGING THE MOVABLE FLANGE OF THE DRIVEN PULLEY TOWARDS THE FIXED FLANGE.