Vehicle parking brake

Claim 1

AN EMERGENCY AND PARKING BRAKE SYSTEM FOR A MOTOR VEHICLE HAVING A HYDRAULIC TRANSMISSION WITH FORWARD AND REVERSE ACTUATORS AND CONTROL VALVE MEANS MOVABLE FROM A NEUTRAL POSITION FOR ALTERNATELY AND SELECTIVELY ADMITTING FLUID UNDER PRESSURE TO ONE OF SAID ACTUATORS FOR DRIVING SAID VEHICLE IN FORWARD AND REVERSE DIRECTIONS COMPRISING, A BRAKE HAVING AN OPERATING ARM MOVABLE TO A FIRST POSITION TO ENGAGE SAID BRAKE AND MOVABLE TO A SECOND POSITION TO RELEASE SAID BRAKE, A CYLINDER ATTACHED TO SAID VEHICLE, A PISTON SLIDABLE IN SAID CYLINDER AND ATTACHED TO SAID ARM, BIAS MEANS ACTING ON SAID ARM FOR URGING THE SAME TOWARD SAID FIRST POSITION WHEREIN SAID BRAKE IS ENGAGED, AND CONDUIT MEANS ATTACHED TO SAID CYLINDER AND SAID TRANSMISSION FOR ADMITTING HYDRAULIC FLUID UNDER PRESSURE TO SAID CYLINDER ONLY WHEN SAID CONTROL VALVE MEANS IS MOVED FROM SAID NEUTRAL POSITION, SAID CONDUIT MEANS BEING ATTACHED TO SAID CYLINDER TO PERMIT THE FLUID TO MOVE SAID PISTON AND SAID ARM AGAINST THE FORCE OF SAID BIAS MEANS TO SAID SECOND POSITION, WHEREBY SAID BRAKE IS ENGAGED ONLY WHEN SAID CONTROL VALVE MEANS IS IN SAID NEUTRAL POSITION.