Patent GB-908441-A (GB)
Title: Train control system
IPC: B61L17/02
Filed: 1960-06-22
Abstract: 908,441. Train control by radio communication. WESTINGHOUSE AIR BRAKE CO. June 22, 1960 [June 22, 1959], No. 21825/60. Class 105. In a railway signalling system employing radio communication for controlling trains in a number of tracks converging from a vehicle receiving yard to a common stretch of track preceding the crest of a hump in a gravity type classification yard, the trains are initially controlled from a receiving yard control panel and as each train occupies an approach stretch of the track the control is transferred to a hump control panel. The radio equipment comprises a transmitter TMU which can be modulated by a number of tones supplied from an audio oscillator unit AOU and a receive unit on each engine under control, e.g. unit ARU on engine A supplied with relay means ASCR which are energized by the reception of particular modulating tone to change cab signal ACS from stop (S) to proceed (Y). The arrangement, Fig. 1, controls two trains A and B, with receive equipment sensitive to modulating tones 1 and 2, respectively, on two tracks designated 1 and 2 and the trains are initially controlled from a receiving yard control panel provided with four pushbuttons F1T1PB &c. which allocate a tone to a particular track, i.e. when button F2T1PB is depressed tone 2 is allocated to track 1. Assuming engine A, controlled by tone 1, has to move a train up to the hump on track 1 and engine B controlled by tone 2 has to operate on track 2. Buttons F1T1PB and F2T2PB are operated, energizing relays F1T1SR and F2T2SR, whereby audio tones 1 and 2 supplied from terminals a and b of unit AOU are applied via front contacts (f.c.s) d relays F1T1SR and F2T2SR, f.c.s d track relays 1TR and 2TR and f.c.s e relays HA1TSR and HA2TSR, respectively, to modulate transmitter TMU. The signals when received by engines A and B operate lamps Y and both trains proceed on their allocated tracks towards the hump crest. As train A enters track circuit 1T, track relay 1TR releases, cutting off modulating tone 1 from the transmitter and the signal on the train changes over to stop (S), similarly train B is halted in track circuit 2T. Release of the track relays provides stick circuits for relays F1T1SR and F2T2SR via back contacts (b.c.s) c relays 1TR and 2TR, respectively, thereby preventing further control from the yard control panel. The trains are now controlled from a hump control panel SCL and if train A on track 1 has to be moved up to the hump lever CM is moved to the T1 position, energizing relay LT1SR via b.c. b relay 1TR and f.c. b slow release relay LOPR, whereby modulating tone 1 is reapplied to the transmitter via f.c. d relay F1T1SR, f.c. b relay LT1SR and f.c. d relay HA2TSR. As train A enters track circuit HAT relay HATR releases, whereby relay HA1TSR releases but relay HA2TSR is maintained energized over f.c. c relay LT1SR and the transmitter remains modulated by tone 1. As humping proceeds train A leaves track circuit 1T and relay 1TR picks up without affecting the proceed tone. When humping is completed and the engine leaves track circuit HAT, relay HATR picks up, picking up relay HA1TSR so that all the hold circuits for relay F1T1SR are open and the relay can release if button F1T1PB has been returned to its original position and relay LT1SR is released. All relays controlling track 1 are now in their normal position. The lever CM on panel SCL may now be moved via its off position (to re-energize relay LOPR) to position T2 and engine B can move its train to the humping position.