Patent GB-790249-A (GB)
Title: Combined manual and automatic route control system for railroads
IPC: B61L13/04
Filed: 1955-07-08
Abstract: 790,249. Railway route control systems. WESTINGHOUSE AIR BRAKE CO. July 8, 1955 [July 9, 1954], No. 19848/55. Class 105. The alternatively manual and automatic route-control system for railways described and claimed in Specification 716,220 which utilizes a train describer system of the type described and claimed in Specification 715,992 is modified so that the changeover to automatic control by the train describer system can only be made when the approach sections of the automatically controllable routes, these routes themselves and conflicting routes are unoccupied and the automatic control is terminated upon the approach of a train to the controlled route when the train is not correctly identified by the describer. To this end the changeover relay APB3, Fig. 1B, which is released for manual route control and picked up for automatic route control by the train describer system is maintained energized only when the identities of trains supplied by the describer correspond with the identities determined by a second grain reporting device. The pick-up circuit of this changeover relay includes front contacts of a manually operable changeover switch incorporated in a routeselecting push-button and of relays to prove that the desired route, the approach sections thereto and conflicting routes are unoccupied and the stick circuit of this relay includes front contacts of relays operated when the train describer and second reporting device correspond. Such relays may be selective cancellation relays picked up when a train passes the second reporting device for cancelling the describer indication stored in the train describer said relays each having a back contact bridged by a front contact of the corresponding storage relay of the describer in the stick circuit of an auxiliary relay picked up when the push-button is operated to pick up the changeover relay, a front contact of the auxiliary relay being included in the stick circuit of the changeover relay so that when the auxiliary relay is released on the non-correspondence of identities of the describer and second reporting device when both the said front contact of the storage relay bridging the back contact of the cancellation relay and this latter back contact are open, the changeover relay is released to condition the interlocking control system for manual operation in which case suitable warning may be given. Routes 2-6 and 2-8, Fig. 1A, are established automatically by repeating relays AP, BP, Fig. 1B, respectively governed by the train describer system in accordance with the indicated route for the approaching train. The changeover relay APBS is picked up by rotation of the common route entrance button 2PB for routes 2-6, 2-8 to its automatic position and then depressing it to close its contact d in the upper position. On the approach of a train for either of these routes the respective relay AP, BP is operated, say route 2-6 so that relay AP is operated in accordance with the route designation indicated by lighting up of lamp AE, Fig. 1A, and route selecting relay ANE is picked up to establish the required route. On release of the push-button 2PB relay APBS is held over its front contact a, upper contact d of the button 2PB, f, c, c BPBS (front contact c of relay BPBS, this relay having been picked up over f, c, d 2PB), wire 22 and f, c, b 12TR, Fig. 1A. Relay BPBS is held over its front contact a over f, c, d 2PB, and back contacts b of relays AN, B, N and NN which are bridged by f, c, f A1, B1, N1, over wires 25a, 26a, 27a. As the train V identified by frequency f 1 passes the first reporting device TD1, Fig. 1A, detecting relay AD is momentarily energized and at f, c, a AD energizes the directional stick relay 12SR over f, c, e 12TR. Relay 12SR has a release time of several seconds, so that when the train enters the section 12T and relay 12TR drops away a stick circuit for relay 12SR is made over f, c, a 12SR and b, c, c 12TR (back contact e of relay 12TR). At f, c, b 12SR relay APBS is maintained energized while f, c, b 12TR is open. At f, c, b AD relay A2 is operated over f, c, b L2 (relay L2 being at this time operated) and back contacts d of the first storage relays A1, B1, N1 and also over b, c, d L1, and the relay A2 is held over its front contact a. At b, c, d A2 relay L2 is released and at f, c, d A2 relay L1 is picked up over b, c, d B2 and b, c, d N2 and is held over f, c, a L1. At f, c, b L1 relay A1 is picked up over f, c, b A2 and held at f, c, a A1. At b, c, d L1 and b, c, d A1 the holding circuits of relay A2 are opened and the relay releases to release relay L1 at f, c, d A2 and pick-up relay L2 at b, c, d A2. At f, c, e A1 lamp AE is lighted to display the indication for route 2-6 and at f, c, b A1 relay AP is picked up over wire 23 and f, c, b APBS. At f, c, a AP the route setting relay for route 2-6, viz. relay ANE, is picked up over f, c, b 1TR, Fig. 1B, #, c, a AP, b, c, b ANW, b, c, e RW, wire 26 and back contacts of a track switch control relay and the corresponding track switch indication relay (not shown). At f, c, c ANE relay 6XS is picked up to operate the appropriate track switch indication relay and operate the signal mechanism to clear the signal 2A and release the approach locking relay 2AS. Should a second train, e.g. for route 2-8, pass the first reporting device TD1 before the first train has passed the second reporting device TD2, relay BD will be momentarily energized and cause its identity to be stored on relay B2. As the first train passes the reporting device TD2 but has not yet passed signal 2A, track relay ITR will be still energized so that on operation of the selective cancellation relay AN, Fig. 1B, at the device TD2 the normally operated slow release repeater relay NBP, Fig. 1B, is released at b, c, a AN to open at f, c, a NBP the stick circuit of the relay A1 over wire 24a and relay A1 releases cancelling at f, c, e A1 the indication AE and releasing relay AP, Fig. 1B, at f, c, b A1 over wire 23. A further stick circuit for relay BPBS is completed at f, c, b NBP so that when relay AN operates and relay A1 releases, relay BPBS is maintained energized. After the passing of the first train beyond the device TD2 relay AN releases and relay NBP is again picked up the indication stored on relay B2 is now transformed to relay B1 which picks up to release relay B2 and light the lamp BE to display the indication for route 2-8 for the second train and energize relay BP over wire 24 and f, c, c APBS. The route entrance and exit relays ANE and 6XS for route 2-6 remain energized over their respective stick circuits and the established route is not interfered with by the release of relay AP or by the picking up of relay BP. The route-setting relay RE for route 2-8 does not operate when f, c, a BP closes because the connection over wire 25 is open at a contact of the track switch control relay and the track switch indication relay and the pick-up circuit of relay 8XS is open at f, c, c RE. When the first train enters section 1T, relay 1TR releases and in turn releases relays ANE, 6XS, the track switch control relay (NPL, not shown) for normal position and the signal control relay for signal 2A to return the signal to stop. When the train vacates the section 17 track relay 1TR picks up again, and operates a timing device which at the end of a predetermined period initiates operations resulting in the picking up of routesetting relays RE and 8XS to set up the route 2-8, reversing track switches 1A and 1B and operating over a route proving circuit the signal control relay for signal 2B to clear this signal. Assuming a third train of a route other than the describable automatic routes 2-6, 2-8 now passes device TD1, relay ND will be operated to energize relay N2 which will store the indication until conditions permit its transfer to relay N1. The directional stick relay 12SR will not be operated by relay ND and in consequence the change-over relay APBS will be released by the track relay 12TR at f, c, b 12TR, thereby releasing relay AP or BP and manual control for the third train ensues. Should the second train be not equipped to provide an indication of its destination and the train reporting device being not therefore actuated, the approach of the train is detected by the release of track relay T2TR which in turn releases changeover relay APBS with the same effect as in the preceding example. In either case the operator will return contact d of push-button 2PB to its lower position and manually set up the route for the second train. Should the first train fail to operate relay AN at the device TD2 and continues on through the route 2-6 and clears:the interlocking, the route' selection relay ANE will be released, switch locking established and the signal 2A returned to stop. Storage relay A1 will remain picked up and prevent the transfer of the identity for the second train from relay B2 to relay B1. As the first train leaves section 1T, track relay 1TR picks up re-establishing the route 2-6, relay AP being still picked up and signal 2A will be recleared which is incorrect for the route 2-8. On operation of relay BN when the second train passes device TD2, the stick circuit of relay BPBS will be opened at TD2, the stick circuit of relay BPBS will be opened at b, c, b BN and one alternative stick circuit is open at f, c, f B1 and the other stick circuit is open at b, c, b NBP, this relay not yet having released. Relay BPBS therefore releases followed by release of relay APBS which at f, c, band c APBS releases relay AP and BP. At b, c, b BPBS and f, c, d 2PB marker light control relay 2CHR, Fig. 1B, is picked up and supplies energy to a marker lamp 2c on the mast for signals 2A, 2B to call the attention of engine men on the second train to the disparity between the signal and the route set and the identity of the train. The correct route is then set manually by operating the entrance and exit butt