GB468539A - Improvements in or relating to railway signalling systems - Google Patents

Abstract

468,539. Electric signalling systems. LORENZ AKT.-GES., C. Aug. 11, 1936, Nos. 22111 and 25280. Convention dates, Aug. 12, 1935 and Oct. 19, 1935. [Class 40 (i)] In a bell signalling system wherein bells may be rung from either of two stations, means are provided whereby, during operation of the bells from one station, actuation thereof from the other station is prevented. As shown in Fig. 1, the bells A may be rung from either of stations X, Y by generators J, J<1>, upon depression of keys T, T<1>. When signalling is effected from station Y, key T<1> is depressed and relay L at station X is operated over the line circuit, the bells A however remaining inoperative. Relay L operates slow-release relay V which illuminates " busy " signal lamp S and operates relay O. Relay O disconnects generator J at station X, shortcircuits a high-resistance winding on relay L and connects the relay directly to the line. Relay L releases owing to the short-circuiting of the high resistance winding but upon receipt of a ringing pulse from generator J<1>, pulls up and reoperates relay V to maintain disconnection of the transmitting apparatus at station X from the line until the ringing mechanisms, viz. clockwork, of the bells is fully operated. In the event that the key T at station X is operated during signalling from station Y a lamp W is operated. Similar operations occur at station Y when transmission is initiated at station X. In a modification the apparatus at each station is arranged to facilitate transmission to bells on each side of the station. In a further modification, provision is made for indicating earthing or breaking of the line wire.