GB190424701A - Improvements in Electric Motor Control Systems and in Apparatus therefor. - Google Patents

Abstract

24,701. British Thomson-Houston Co., [General Electric Co.]. Nov. 14. Reducing-valves; actuating valves; check valves; plug cocks; handles.-Relates to pneumaticallyactuated master-control systems for electricallypropelled trains. The pneumatic devices or relays are operated by supplying compressed fluid, such as air, at different pressures through the mastervalve, which is adapted to reduce the air pressure in different positions. The master-valve or controller is shown in section in Fig. 3. It comprises, (1), a plug valve 26 for determining the order in which the pipes receive the air, and consequently the direction of movement, and, (2), a disc or slide valve 27 for connecting to the train-pipes and controlling the pressure through reducing-valves in certain of the ports. The reducing-valves may be of any desired construction, but as shown consist of a slide valve 34 loosely mounted on a piston 35 slightly smaller than the chamber 36. It is adapted to close the port when the proper pressure has been reached. A chamber 39 communicates by a small passage 42 with a chamber 40 separated from the chamber 36 but normally communicating through a small valve 43. A spring-pressed diaphragm 45 is arranged in the chamber and, when moved inwardly, lifts the valve 43 from its seat. The valve is so proportioned that when open the compressed air can escape through it more rapidly than it can pass the piston 35, so producing a differential pressure and allowing the spring to return the piston and close the port 47. The main valve seat has three ports connected to the chambers 37 of the reducing- valves, and with other ports leading to the chambers 39, and one leading to exhaust. The valve 27 for making the desired connections is operated by the handle h', and according to its position supplies air of, say, 10, 20, or 30 lbs., and operates the relays in due succession. The handle is provided with a press-button 72, as described in Specifications No. 9807, A.D. 1903, and No. 17,020, A.D. 1904, [Abridgment Class Electricity, Regulating &c.], so that the controller is returned to the' off' position should the handle be released.