Transmission control

Claim 1

FOR USE WITH A VEHICLE HAVING A REVERSIBLE TRANSMISSION WITH A PAIR OF FLUID ACTUATED FORWARD AND REVERSE DIRECTION CONTROLLING CLUTCHES, A SOURCE OF FLUID PRESSURE AND A FLUID PRESSURE BRAKING SYSTEM, A CONTROL RESPONSIVE TO BRAKE APPLICATION FOR CHANGING THE TRANSMISSION DRIVE DIRECTION AND COMPRISING A DIRECTION CONTROL VALVE FOR SELECTIVELY CONNECTING THE FORWARD AND REVERSE DIRECTION CONTROLLING CLUTCHES TO THE SOURCE OF FLUID PRESSURE FOR ENGAGEMENT, SAID CONTROL VALVE HAVING A BODY, A FIRST BORE LOCATED IN SAID BODY, A SECOND BORE LOCATED IN SAID BODY, SAID BORES BEING SEPARATED BY A PARTITION, A SPOOL MEMBER SLIDABLY DISPOSED WITHIN SAID FIRST BORE AND OPERATIVE IN ONE POSITION TO ENGAGE THE FORWARD DIRECTION CONTROLLING CLUTCH AND DISENGAGE THE REVERSE DIRECTION CONTROLLING CLUTCH AND OPERATIVE IN ANOTHER POSITION TO DISENGAGE THE FORWARD DIRECTION CONTROLLING CLUTCH AND ENGAGE THE REVERSE DIRECTION CONTROLLING CLUTCH AND A PISTON SLIDABLY DISPOSED IN SAID SECOND BORE AND CONNECTED TO SAID SPOOL MEMBER, A SHIFT SELECTOR VALVE OPERATIVELY CONNECTED TO THE BRAKING SYSTEM, A PAIR OF FLUID CONDUITS FOR CONNECTING SAID SECOND BORE ON EACH SIDE OF SAID PISTON WITH SAID SHIFT SELECTOR VALVE, SAID SHIFT SELECTOR VALVE BEING OPERATIVE TO DIRECT BRAKE FLUID PRESSURE TO EITHER SIDE OF SAID PISTON SO THAT SAID SPOOL MEMBER IS SHIFTED TO ONE OR THE OTHER OF ITS POSITIONS IN RESPONSE TO BRAKE APPLICATION, AND A PRESSURE REGULATING VALVE FOR PREVENTING COMMUNICATION OF BRAKE FLUID PRESSURE TO SAID SECOND BORE UPON BRAKE APPLICATION UNTIL A PREDETERMINED BRAKE FLUID PRESSURE IS REACHED IN THE BRAKING SYSTEM.