GB333365A - Hydraulic brakes - Google Patents

Abstract

333,365. Coatalen, L. July 12, 1929. Fluid-pressure.-In hydraulic braking systems having separate pipes between the master cylinder or cylinders and the various brakes or sets of brakes the pressures in the separate pipes act normally in balance upon the opposite faces of a valve which at all times prevents communication between the two pipes and when subject to unbalanced pressures moves to obstruct the pipe line in which the pressure is lower, to prevent loss of oil should one pipe leak or break. The pipe lines 2, 2 and 3, 3 are connected with opposite ends of a valve chamber containing a floating valve 5 in the form of a piston restrained in its balanced position shown by a groove 11 engaged by a spring-pressed ball 12. If one pipe line fails the valve will move to close the appropriate outlet 9 or 10 preventing loss of oil and allowing the undamaged pipe line to function. The valve also closes the inlet pipe 7 or 8. To hold the valve at the end of its travel additional grooves 13 are arranged to be engaged by the ball 12. The ends of the valve chamber carry detachable caps 14, upon removal of which the valve can be pushed back to its central position. In a modification oppositely acting springs return the valve 5 to the central position and the valve acts only to cut off the supply at the inlets 7 or 8. The device may be used with the equalizing system described in Specification 331,700, the resistance of the spring-pressed ball 12 slightly exceeding any resistance in the equalizing device so that the pressure on the valve is normally always balanced.