Patent GB-532683-A (GB)
Title: Improvements relating to railway traffic control apparatus
IPC: B61L19/06
Filed: 1939-07-24
Abstract: 532,683. Railway control apparatus. WESTINGHOUSE BRAKE & SIGNAL CO., Ltd- July 24, 1939, No. 21505. Convention date, Jan. 14. [Class 105] In interlocked railway traffic control apparatus for points and signals the setting of each route is effected by the single operation of a single contact (push-button or equivalent) appropriate to the selected route. Preferably the buttons are arranged on a panel in vertical columns, Fig. 2, each column containing buttons appropriate to a particular entrance, the routesetting buttons in each column being appropriate to the different exits. Each column contains a button 2AnP ... 10AnP by which a set-up route may be cancelled, and certain columns contain "direct" route buttons 2-8DP, 10-4DP, and call-on buttons 4CP, 6CP, 8CP. An upper horizontal row contains buttons 1NP, 1RP, 3NP, 3RP, and 5NP, 5RP by which the points may be individually controlled when necessary, and a button EP by which the setting of the points may be shown on a mimic diagram, illustrated in Fig. 1 and corresponding to the lay-out shown in Fig. 4. This shows through routes AD, BE with cross-overs having points 1A, 1B, 5A, 5B, a branch C with point 3 and signals 2, 4 ... 12. The points are operated by corresponding machines SM and the lines are in insulated sections 1T ... 10T with corresponding track relays TR. The mimic diagram has transparent sections corresponding with the track sections and signals which may be selectively illuminated by red and white lamps as described in Specification 499,340, to show the various conditions prevailing. Should a track relay not energize when its section is free, with consequent locking of points which would interfere with control, the defective section may be cancelled by a corresponding button 1AP ... 7AP on a separate panel, Fig. 3, which may be under seal, and the points individually controlled by buttons 1NP ... 5RP, Fig. 2, in known way, as, for example, in Specification 499,340. Figs. 20, 21 show an arrangement of lamps 1, 2 of small dimensions for use with the mimic diagram, one or both of which may have a coloured transparent cap 8, carried by a reflector with walls 3, 4 directing light to the transparent section 5 of the front panel 7. An insulating panel 10 carries fixed conducting sleeves 11 which receive removable insulating plugs 12 provided with central contacts 18 and screwed metal lamp-receiving sleeves 14 which contact with sleeves 11. Contacts 18 have flexible conductors 17 with terminal plugs 16 inserted in bus-bars 15. Conductors 19,21 make contact with sleeves 11. The lamps are thus readily removable. With the system as described a set-up route is generally automatically cancelled by passage of a train through the route, but certain routes may be rendered " direct " or " permanent " so that they are automatically re-established after passage of a train. The system is also arranged for "elastic transit" with locking in front and release at the rear of each train. The system uses a single route relay of polar type, or preferably of the type having two windings with a common return for two opposite routes, each winding corresponding to one route and the direction being determined by a signal preparation relay. Fig. 4 shows certain control and checking relays, but the Specification gives the necessary circuits in full, and traces in detail by way of example, establishment of route 4-8 by pressing button 8<SP>1</SP> of entrance 4, control of the points, locking of the points, clearing of signals 4 and 12, lighting of signal lamps and corresponding indication in the mimic diagram, manual cancelling of route 4 to 8 via point 1, establishment of a fractional route 4-12 by pressing button 12 of entrance 4, and of fractional route 12-8 pressing button 8 of entrance 12, establishment of a "permanent" route 2-8 by pressing button 2-8 DP of entrance 2, call-on operation assuming route 4-10 has been established and dissolved by a train stopped in a position in which it fouls circuits 7T, 3T, providing additional safety arrangements by interposing in an approach circuit of a presence section of short length preceding the signal or by use of a pedal lever replacing a particular relay circuit, and safeguard against faulty operation as by simultaneously pressing a number of buttons associated with the same entrance, or by operation of two control buttons for routes which are incompatible as involving different positions of the same point. A modified circuit arrangement is also described permitting use of an ordinary relay in place of the relay with two windings.