Patent GB-191322224-A (GB)
Title: Improvements in and relating to Electro-pneumatic Air Brake Systems.
IPC: B60T13/66
Filed: 1913-10-02
Granted: 1914-10-01
Abstract: 22,224. British Thomson-Houston Co., [General Electric Co.]. Oct. 2. Fluid-pressure.-An air brake, comprising the usual main-reservoir pipe 1, train-pipe 9, driver's valve 5, triple valve 10, auxiliary reservoir 12, and brake cylinder 27, is provided also with an electric controlling-switch 6 and selector switch and valve 7, 8, having circuits arranged as shown in connexion with train wires 46 ... 50 for actuating electro-magnetic application and release valves 31, 39 controlling a distribution valve 18, and also an electromagnetic charging-valve 30 and emergency venting-valve 69. The controller contacts 6 and driver's valve ports 5 are indicated at the left side of the Figure, and the positions for operation are shown by dotted lines, namely (reading from the right) the release, retain, lap, first and second service, and emergency positions. The selector-switch contacts 7 and valve port 8 are also indicated, there being two positions, for pneumatic and electric operation respectively (reading from the right). The pneumatic control is normal and occurs simultaneously with the electric control, with the exception that, in an electric service application, the service exhaust port 13 of the driver's valve is closed by an electric valve 66. This valve opens automatically, however, if the electric supply fails, and so allows a pneumatic application to be made, such application taking place even if the driver's valve is in lap position, the train-pipe being in such case vented through an additional driver's valve exhaust 67, which is connected to the exhaust 13 by the port in the valve 8 and a passage 68. For electric control, the selector switch and valve at the front of the train are placed in the electric position, the others throughout remaining at the pneumatic position. In an electric service application, the train wire 49 is energized from the trolly by wires 57, 58, 65, controller switch 6, and wire 64, thereby opening the application valve 31. The wire 49 is connected at the rear end of the train by a coupling 51 to the train wire 50, which is therefore energized and closes an electro-magnetic switch 53, whereupon the train wire 47 also becomes energized through wires 57, 58, 48 and switch 53. The energization of the wire 47 closes the charging-valve 30 between the auxiliary reservoir 12 and a pressure reservoir 28, and also the release valve 39, at the same time opening a valve 32 connected to the valve 39. Air then flows from the pressure reservoir 28 past the valve 31 to an application reservoir 29 and the left side of the piston 17 of the valve 18, which is thereby moved to the right to shut off the triple-valve exhaust 20 from the atmospheric port 19, and to unseat a valve 23, past which air flows from the control pipe 1 to the brake cylinder 27. When brake - cylinder pressure equalizes with that in the application reservoir, the valve 18 is moved back to a lap position, and the valve 23 closed by the spring 24, thereby cutting-off the supply. The valve 66 is closed in an electric service application by current supplied by wires 47, 61, the selector switch 7, and wire 62. In the lap position, the wire 47 is energized directly by the circuit comprising wires 57, 58, 65, controller 6, wire 60, selector switch 7, and wire 61, and the brakes are maintained on. A full release is obtained by returning the controller to the release position, whereupon the wire 47 is deenergized and the valves 30, 39 opened, thus releasing the air acting on the piston 17 through an exhaust port 37. A partial release is obtained by moving the controller to the release position and then to the retain position, in which the same conditions hold as for the lap position. In the emergency position of the controller, the wire 46 is energized to open trainpipe venting-valves 69. These valves may be operated automatically when the triple valve moves to the emergency position, by causing the air vented from the train-pipe through the triple valve to open a valve 72, thereby closing a switch 74 and energizing the wire 46 from the wire 48.