Dual-cylinder hydraulic actuator for automotive clutch and brake control

Claim 1

IN A COMBINED DUAL MASTER CYLINDER AND A TWO-COMPARTMENT FLUID SUPPLY RESERVOIR THERREFOR: A PAIR OF COAXIAL TELESCOPICALLY-RELATED CYLINDERS; A PAIR OF PISTONS RECIPROCABLE IN SAID CYLINDERS, RESPECTIVELY; SPRING MEANS FOR BIASING SAID PISTONS TOWARD FULLY RETRACTED POSITIONS; A PAIR OF COMPENSATING PORTS BETWEEN SAID RESERVOIR COMPARTMENTS AND CYLINDERS, RESPECTIVELY, SAID PORTS BEING NORMALLY OPEN WHEN SAID PISTTONS AND ONE OF SAID RESERVOIR INTAKE PORT BETWEEN SAID PISTONS AND ONE OF SAID RESERVOIR COMPARTMENTS; A FLUID-RETAINING LAND SLIDABLY INTERFITTING ONE OF SAID CYLINDERS AND COOPERABLE WITH BBOTH OF SAID PISTONS TO DEFINE A PAIR OF OVERLAPPING CONCENTRICALLYRELATED ANNULAR CONSTANT VOLUME STATIC FLUID CHAMBERS NORMALLY COMMUNICATING WITH SAID INTAKE PORT AND THE COMPENSATING PORT CONTROLLED BY ONE OF SAID PISTONS; A ONE-WAY FORCE-TRANSMITTING MECHANICAL CONNECTION BETWEEN SAID PISTONS ENABLING OPERATING FORCE TO SIMULTANEOUSLY ACTUATE BOTH PISTONS IN A FLUID-PRESSURIZING DIRECTION: AN OPERATOR-OPERATED MEMBER OPERABLE FROM NORMALLY RELEASED POSITIONN TO ACTUATE SAID PISTONS TO INITIALLY CLOSE SAID COMPENSATING PORTS AND THEN PRESSURIZE THE FLUID WITHIN SAID CYLINDERS; AND A PAIR OF DISCHARGE PORTS COMMUNICATING WITH SAID CYLINDERS; RESPECTIVELY, FOR CONVEYING SUCH PRESSURIZED FLUID THEREFROM.