Patent GB-190224790-A (GB)
Title: Improvements in Automatic Fluid Pressure Brake Apparatus for Railway Vehicles
Inventor: CORRINGTON MURRAY
Filed: 1902-11-11
Granted: 1903-07-09
Abstract: 24,790. Corrington, M. Nov. 11. Brakes, compressed - air. Relates to means for re - charging the auxiliary reservoirs while the brakes are applied, and afterwards releasing them with certainty. Fig. 1 shows a quickacting triple-valve apparatus. Air from the train pipe is allowed to enter the chamber 8 through the passage 61, and the valve 32 is controlled by the piston 43, the stem of which has a valve 45. When the piston 4 is slightly to the left of the ports 11, the brakes have been set, the piston 43 is balanced, and the ports &c. 90, 91, 92, 22, 21 are at atmospheric pressure. The brakes may be applied with greater force by venting the train pipe, and the auxiliary reservoir is re-charged by gradually raising the pressure in the train pipe, air flowing through the ports 11 and passages 12, 13, and this happens so long as the valve 31 is seated. When the pressure in the train pipe and passage 35 is increased, the diaphragm 30 opens the valve 31, and the pressure on the right of the piston 43 is vented through the ports and passages 47, 48, 90, 91, 92, 22, 21, 24, and 20 until the valve 45 is opened, when the piston 43 moves quickly to the right and stands between the ports 47, while the spring 33 closes the valve 32. Air in the chamber 80 exhausts through the passage 93 and one of the ports 47, round the piston 43, through the other port 47, past the valve 45, and thence by the ports and passages 90, 91, 92, 22, 21, 24, 20 to the atmosphere. The piston 81 is then unbalanced, and its stem forces the triple valve into the release position shown in Fig. 1, when the port 21 is again opened to the cavity 16, and air flows back through the passage 94 and rebalances the piston 43, and the valve 32 is opened. The emergency mechanism is the same as that shown in Fig. 2 of Specification No. 11,932, A.D. 1901. In the application to apparatus having emergency mechanism of the kind shown in Fig. 1 of the Specification quoted, a spring stem is fitted to the right end of the triple-valve piston while a piston corresponding to the piston 81 is fitted to its left end. The re-charging passage may be closed when the triple valve moves to the release position by modifying the main slide valve and fitting a slide valve in lieu of the valve 7 to perform the graduating function. The re-charging passage is in two sections 13, 113, Fig. 4, connected by ports 65, 66 in the bush 17 while the slide 5 has an extension with a cavity 67 which, when the triplevalve is in the brake-setting position, bridges -these ports. Directly the brakes are released, the cavity 67 passes to the left of the ports and closes them. In the modification shown in Figs. 5 and 6, the recharging passage is not controlled by the piston 4, but is always open to the train pipe, and, in this case, the ports 68, 69 extending through the valve 5 are fitted in lieu of the cavity 67, and a cavity 114 in the valve 105 opens or shuts them. In another modification, a supplemental cavity 107, Fig. 6, controls the port 21, and two ports 108, 109, which lead through the top of the valve 5 to the cavities 24, 107 respectively, are bridged by the cavity 110 in the face of the valve 105, the parts being arranged so that the cavity 110 connects the ports 108, 109 when the triple valve is in the position for re-charging the auxiliary reservoir.