| 摘要 |
1,113,502. Railway vehicle braking system. GRESHAM & CRAVEN Ltd. 5 Aug., 1966 [23 Aug., 1965], No. 36004/65. Heading F2F. A railway vehicle vacuum braking system comprises at least one brake cylinder having two chambers 4, 5, a train pipe 10 connected to one 5 of the chambers and a further train pipe 11, for separately charging the other chamber 4 during a brake application. A piston 3 separating the chambers 4, 5 is provided with a one-way valve 6 such that gas can pass from chamber 4 to chamber 5 and, on movement of the piston 3 in the brake applying direction, a rolling ring 36 moves past a port 7 in the piston to cut off all possible connection between the two chambers 4, 5. An automatic isolating valve 14 is interposed between the train pipe 11 and the chamber 4, vacuum above a diaphragm 26 of the valve allowing atmospheric pressure on a flange 27 of a stem 25 to overcome the bias of a spring 30 such that the stem 25 moves to unseat a valve member 23. The ultimate pressure in both train pipes is limited, the ultimate pressure in train pipe 10 being lower than that in train pipe 11 such that the train pipe 11 can be evacuated through the valves 14 and 6 although an exhauster is connected to this train pipe 11. A reservoir 18 is also evacuated. Thus a brake application can be effected even if the train pipe 11 is defective, the valve 14 closing automatically. When the brakes are applied communication between chambers 4, 5 is cut off with the result that on release of the brakes the pressure in chamber 5 becomes lower than that in chamber 4, the piston 3 then moving to the brake release position. A manually actuated valve 35 is provided between the two chambers. |
