GB710536A - Fluid pressure brake apparatus - Google Patents

Abstract

710,536. Fluid-pressure brakes. WESTING- HOUSE AIR BRAKE CO. March 11, 1952 [March 26, 1951], No. 6309/52. Class 103(1) A triple valve for railway fluid pressure braking apparatus comprises means whereby the increase in volume of a control chamber 41, as a result of flexure of the diaphragm assembly, is prevented from reducing the pressure in the control reservoir 5 to such a degree that there would be delay in obtaining a sufficient pressure differential between the chambers 41 and 48 to move the slide valves 38 and 40. such delay undesirably slowing down an application of the brakes throughout a train. The means for preventing a reduction in pressure in the control reservoir 5 comprises the provision of a non-return valve 63, located in the manually operable release valve device 9, which allows fluid to flow from the auxiliary or supply reservoir 3 by way of passages 12 and 42 to make up the pressure in the control reservoir. The valve 63 is relatively large to provide a sufficient flow and is held shut by a spring 66, the pressure from which is the very minimum required to keep the valve on its seat and such that it will be opened. by a very slight differential between the pressures in the control reservoir 5 and supply reservoir 3. The hand release device 9 included on pivoted lever 57 which opens in succession first a valve 50 which vents the brake cylinder 4 and then a valve 49 which vents the supply or auxiliary reservoir 3. Further movement causes through spindle 68 a positive opening of the valve 63 to vent the control reservoir 5. The triple valve assembly includes a quick service valve device 7 and charging device 8 and is generally similar to that described in Specification 702,100.