Patent GB-533218-A (GB)
Title: Improvements relating to railway traffic controlling apparatus
IPC: B61L19/06
Filed: 1939-08-01
Abstract: 533,218. Route-setting apparatus. WESTINGHOUSE BRAKE & SIGNAL CO., Ltd. Aug. 1, 1939, No. 22346. Convention date, Jan. 25. [Class 105] In an entrance-exit electric interlocking route-control system in which a route between two points is set up by momentary operation in succession of corresponding route-end buttons, the direction of the set-up route depending on the order in which the buttons are operated, operation of the entrance button energizes a route preparation system for each route issuing from the corresponding entrance, and subsequent operation of the selected route-end button effects setting up of the selected route and effects release of all the other route-preparation systems initially energized. Means are also provided for operating the switches by individual levers when desired, and for operating a call-on signal by operation only of the entrance button for the route governed by the signal without the use of an auxiliary button. All operations are indicated on a track diagram by selective and distinctive illumination of sections of the diagram. Fig. 1F shows a simple track lay-out illustrating the invention and comprising parallel tracks having insulated rail-sections 1T, 5T, 24T, 21T, 19T, 4T, 3T, 7T connected by cross-overs 1, 5, 7 with respective switches 1A, 1B, 5A, 5B, 7A, 7B, and a siding with section 6T connected with the lower main track by switch 3. Each track section is provided with the usual normally energized track relay such as 21 TR, 19TR, 7TR. Each track relay controls a slow pick-up slow-release repeating relay such as 7TP. Each switch is operated by a switchmachine such as 7A-SM, 7B-SM provided with the usual motor controlled by contacts of a polarized relay such as 7WR, each switch or pair of switches being operated to normal, as shown, or to reverse, when the polar contacts are closed to left or right, respectively. Each switch is also provided with the usual circuit controller for a polarized switch indication relay such as 7WP. Each switch indication relay controls a pair of switch correspondence relays such as 7NWC, 7RWC, each of which is energized only when relays 7WR, 7WP are energized in corresponding ways. Signals 4A, 10A are high-speed signals governing main-line movements, each having a distant signal 19, 24. Signals 2, 4C, 6, 8, 10C, 12 are slow-speed signals, 4C, 10C also serving as call-on signals controlled by manually governed stick-relays not shown. Each signal is provided with the usual back lock or signal indication relay energized only when the corresponding signal indicates stop. Contacts 4RGP, 2RGP of two such relays are shown, contro'ling approach-locking relays 4AS, 2AS. These relays also control lamps of the panel signal indicators GK. Each slow-speed signal indicates clear or stop. Relays, not shown, controlled by the next signal in advance control the polarity of current supplied to the mechanism for each high-speed signal 4A, 10A to provide a third or caution indication. Manual control of signal mechanisms by the route buttons is controlled by signal control relays HR (not shown) contacts of which, such as 4HR, 2HR, in conjunction with back-lock contacts 4RGP, 2RGP control relays 4AS, 2AS referred to above. For each slow-speed signal such as 2, the approach-locking relay such as 2AS is released when the corresponding signal control is energized to clear the signal, and is picked up automatically when the signal is put to stop by a train entering the route governed by the signal. Relay 2AS may be picked up by putting signal 2 to stop manually, its energization being delayed by a time element. 2TE in known manner. Relays such as 4AS associated with high-speed signals are similarly operated, except that a longer time interval is provided by a time-element 4TE by use of an auxiliary stick relay 4TES, the time delay being nullified when the signal is manually put to stop when an approach zone in rear of the signal is occupied. The approachlocking relays control corresponding groups of section locking relays ES, WS as shown, one relay ES or WS being provided for each direction in each track section. These relays function so that when a signal is cleared, a series of relays, including one for each section governed by the signal, will be released, these relays being re-energized successively when the corresponding track-sections are vacated. The section locking relays ES, WS, together with the track relays TR control the switch-locking relays, not shown, and these govern the circuits of the switch control relays, such as 7WR so that when a signal control relay (HR) is energized to clear a signal, the switch control relay circuit is opened to lock the switch in the position it then occupies. The switch locking relays also control the circuits of the signal mechanism so that the clearing of a signal is dependent on the locking of each switch in the corresponding route, while relays AS also control the signal circuits to provide time and approach locking for opposing signals. The remaining relay and lamp circuits used in the invention are not here reproduced, but the Specification gives the necessary circuit diagrams for two suitable arrangements and traces in detail the circuits involved in typical operations such as referred to below. Fig. 1G shows the corresponding track diagram or panel composed of translucent sections 2K, 1K, 1RK &c. each capable of illumination by one or other of a pair of lamps in an enclosure at the rear of the section, the lamps described being red and white. Approach sections 4AK, 10AK have red lamps only. Push-buttons 2P, 8P, 10P, 4P, 12P, 6P are located at positions corresponding to the signals. Each button normally occupies a mid-stroke position and closes one or more normally open contacts when pushed, or opens a normally closed contact when pulled. Each button is also provided with a centrally disposed lens 2GK, 8GK, &c. capable of illumination by one or other of a pair of lamps. These buttons normally serve for setting up a route by operation of a selected pair of buttons, but auxiliary switch levers 1W, 3W, 5W, 7W are provided on the panel for individual operation of the switches when desired, each lever normally occupying a central position from which it is moved to left or right to operate the switch to normal or reverse. The circuits are arranged so that such operation is effective only if the suitable conditions are shown by the energization of the corresponding switch-locking relay. Each lever also controls the circuits of the white lamps for the switch sections of the diagram so as to indicate the actual position of the switch when the lever is moved from central position. In operation, assume for example, that conditions are normal as shown, and that it is desired to clear signal 4A to pass an approaching train over route 4-12. When the train enters section 21T, Fig. 1F, release of track relay 21TR opens contact 9 and de-energizes approach relay 4AR and operates a contact, not shown, for the red lamp of indicator 4AK to inform the operator of the train approach. Operator then presses button 4P. This energizes a preliminary route selector for each available route, each selector comprising an entrance section stick relay and a series of tandem-connected relays including one for each remaining section of the route. These relays are interlocked to prevent energization of similar relays for conflicting routes having different entrances, and each is arranged so that it will not be energized when the corresponding track switch is locked in a position not in accordance with the route identified with the relay. Energization of entrance stick relay also causes red illumination of indicator 4GK to mark button 4P as an operated entrance button. Energization of the last relay in each series energizes the white lamp of the indicator exit sections 1K, 10K, 12K, thus marking buttons 8P, 10P, 12P as available exit buttons. At the same time the preliminary route selectors operable by these buttons are rendered non-responsive. Button 12P is now pressed. This energizes a series of final routeselector relays, including an exit stick relay, one of which is associated with each button. Energization of these relays extinguishes the white lamps of indicators 1K, 10K, restores buttons 8P, 10P so that they may now be operated to establish other routes, releases the remaining previously energized preliminary route selectors and electrically isolates the selector relays for route 4-12 from relays for all conflicting routes, button 6P being inoperative as controlling a conflicting route. The white lamp of indicator 4K is lit to indicate completion of the route selection. Illumination of switch indicator sections depends on completion of the requisite switch operations. As, in the present example, the switches are assumed to be initially in the requisite normal position, sections 7BNK, 5BNK, 3NK, 1BNK become illuminated as soon as the route selection is completed. The signal control relays are then energized, together with switch-locking for all switches governed by the signal and on which ultimate clearing of the signal by energization of its control relay depends. Contacts closed by energization of the indication relays lights white lamps for indicators B1K, 3K, 7K, completing strip lighting of the indicator for the selected route. Signal 4A then clears and release of a relay contact causes the light indication of button indicator 4GK to change from red to green. This light is extinguished when the train enters section 4T, consequent on deenergization of track relay 4TR (not shown). At the same time the white lights of indicators 4K, 1BNK, B1K are replaced by red, which remains whilst section 4T is occupied, and are extinguished when the section 4T is vacated. Similar action occurs with successive sections. The arrangement of relays is such that a destinctive "approach locked " indication of track switches is prov