Patent GB-473310-A (GB)
Title: Improvements relating to remote control systems
IPC: B61L7/08
Filed: 1936-04-09
Abstract: 473,310. Electric signalling and remote-control systems. WESTINGHOUSE BRAKE & SIGNAL CO., Ltd. April 9, 1936, No. 10582. Convention date, July 16, 1935. [Class 40 (i)] [Also in Group XXX] In an electric signalling and control system in which selection is performed by a code comprising makes and breaks in a line circuit, both makes and breaks form part of the code and are arranged to be of short, medium or long duration. The invention is described as applied to control of railway signals and points and to the supervisory signalling of the position of these units and the condition of sections of the track. Interlocking arrangements are provided to prevent the transmission of codes which would set up conflicting conditions, lamps flashing if the levers for an improper positioning are operated. The system is normally non-automatic, but a key enables automatic working to be established over a section of the track if required. Specification 415,787 is referred to. Transmission of a control code. The apparatus for the selection and control of three remote units is shown in Figs. 1 and 2, the line circuit being connected to terminals XY and being connected in series through all the sub-stations as indicated in Fig. 10. The apparatus as shown provides for seven code elements, five of which are used for selecting purposes and as each element can have any one of three values a total of 243 selections can be arranged. To operate the switchcontrol relay WS, Fig. 4, the lever W, Fig. 2, is moved to the right. Relay N1 releases and relay S1 pulls up. If the signals at the remote point are set so that operation of the points controlled by relay WS may be made and the approach track sections are not occupied, relay WL1 is energized so that relay P1 moves its contact to the right and relay N1 re-energizes and locks. When relay N1 released, the flasher relays FR1, FR2 commenced to interact and lamp WE to flash, but, as, in this instance, relay S1 pulls up at once this flashing stops immediately and the lamp shines steadily. If however, relay WL1 is de-energized, lamp WE continues to flash to indicate that movement of the points is not possible, the flashing stopping when the lever W is reset or when WL1 pulls up. The lamp WE remains lit until either WK is reenergized by the receipt of a supervisory code or lever W is again operated. Relay CS1 pulls up and relay OMR energizes and locks allowing relay OT to open the line circuit at contacts ot4. Relay OR releases and relays MC, L and LB energize. Relay OP operates and locks and lamp CE lights and remains steadily lit for the duration of the code. When relay OR released, slow relay MO is de-energized but before it falls away relay SOR picks up to prepare the short-code registering circuit. The first element is however long so that no operation takes place at this stage. After its slow period relay MO falls away, relay SOR is de-energized, the medium-code relay MOR pulls up and relay L begins to de-energize. When relay L has fallen away, relay MOR is released and the long-code relay LOR energizes. Relay PT is now energized from OP6 over back contacts of MO and L. Relay CT operates and OT releases to terminate the first break. Relay OR pulls up and relays LOR and OP are de-energized but before they fall away, relay OA is operated and locks. Relay SCR prepares the circuit for registering a short make and relay MC de-energizes slowly. As the first make is not short, relay MC falls away and relay MCR is energized in place of relay SCR. If the first make period is long relay L also releases to enable the long code registering relay LCR to pull up in place of MCR but as shown the code is medium so that relay PT is energized before L falls away from contact 2 of code relay CS1 over wire 26, contacts of OE, OD, OC, OB joined by jumpers 27-30, and a contact of OA. Relay PT moves its contacts to the left, relay CT de-energizes and relay OT pulls up to open the line circuit again. When OR falls away relay OB is operated over contacts of OA and MCR. The remaining digits of the code are similarly transmitted, the breaks being terminated by connections to the right-hand winding of relay PT over leads 20, 21 or 22 depending on the jumpering between the contacts of the relay group OAOE and the marking supplied by relay CS1 whilst the makes are terminated by connections over 23, 24 or 25 to the left-hand winding of PT. The relays SOR, MOR and LOR prepare the registering circuits for the slow, medium and long break periods and relays SCR, MCR and LCR prepare them during the make periods. The number of relays OA-OE required depends on the number of stations connected to the system, one relay OE sufficing for three units and three for nine units ; nine relays OE and three relays OD for twentyseven units ; twenty-seven relays OE, nine relays OD and three relays OC for eighty-one units and so on. The sixth element of the code associated with relays CS1 is short (wire 23 being marked by CS1 over OE4 and 26) and consequently relay OF1 is energized over 43 and 32 when the line opens to begin the seventh element. The seventh element is the control pulse and this is long or short depending on the position of relay P1. In the condition being considered, contact 2 of relay P1 is to the right and the circuit of PT is completed over wire 22 and a contact of relay OF1 when a long pulse has been sent. Relays S1 and CS1 release and, when relay OR pulls up at the end of the seventh and final element of the code, relays LOR, MO and L pull up and relays OF1, LOR, MC. L, LB, LBP and MOR release. Relay PT is operated to the left and relay CT releases. Reception of control code. At the remote stations relays IR-7R &c. have followed the movements of relay OR and at the station shown in Figs. 3-4 the contacts of relays IA-IE are so connected with respect to the contacts of relays SCR, MCR, LCR, SOR, MOR and LOR that the relays have each been connected up when the pulses terminated and relay IF1 was operated by the sixth pulse. Had the sixth pulse been of medium duration relay IF2 would have been selected whilst a long sixth pulse would have enabled IF3 to pull up. Also had the code been different at least one of the relays IA-IE would not have been connected to the correct contact of the timing relays when the differing pulse terminated and the code relays would have released. Relay IMR is not energized during reception and relays PT, IT and CT are not used. As described the seventh pulse is long so that relay LOR is energized when relay IR pulls up at the end of the code and relay WS is operated to the right over wire 152 and contact 3 of relay IF1. Had the pulse been short relay WS would have been energized to the left over wire 150 and IF1-1. As the signals are all at stop and the track is unoccupied relays LMR, RMR and TR are all energized so that a circuit is completed to energize relay WR which controls the points motor (not shown). Transmission of supervisory code. When relay IF1 pulled up, circuits were prepared to initiate transmission of a supervisory code. Such transmissions are also initiated automatically when the track relay AR energizes or de-energizes when the switch SM associated with the points motor moves and when relay WR, which indicates correspondence between relay WS and the switch releases. When relay WS operates as above described, relay WR falls away, KR de-energizes and WV closes its right-hand contacts to cause the seventh element of the transmitted signal to be of medium length. Relay IST pulls up and IS energizes. Relay ICS pulls up, IMR energizes and IT operates. The code is then transmitted exactly as described above for a control code, the relays at the sub-station operating in the same manner and sequence as those described at the main station. The first element of the supervisory code indicates the condition of the associated track section and is determined by the position of the contacts of relay AV, the element being short when contact 1 of AV is to the left and medium when AV is closed to the right. Code elements 2-6 are determined by the markings by ICS on contacts 4, 5 and 6 of relays IA-IE whilst the seventh code element is determined by the position of contact 1 of relay WV and indicates the locked or unlocked condition of the switch. Two transmissions take place in the present instance, the first indicating the unlocked condition of the switch and the second, initiated when relay KR becomes energized in the reverse direction, indicating that the switch has changed over. Reception of supervisory code. At the main station, Figs. 1-2, relay OR falls away with the first opening of the line circuit and as relay OMR is not energized the first element of the code energizes either relay TC or TO, depending on whether the element is short or medium, and the energized relay locks..The elements 2-6 of the code operate the relative relays OA-OE and as the code under consideration is controlled by relay CS1, relay OF1 is picked up. Relay OF1 releases relay WK if this relay is not already back and lamp WE is lit to indicate that the switch is unlocked but as this lamp was lit when the control code was sent, the seventh element of the first supervisory code in this instance has no effect on the apparatus, but the seventh element of the second code, which is long, causes a pulse to pass over reversed contact PI-3 to re-energize relay WK and extinguish the indicator lamp WE. Had the control code operated the remote switch to normal the seventh element of the second indication code would have been short and would have caused a pulse to pass over contact PI-3 in its left-hand position to re-energize relay WK. When relay OF1 energized at the beginning of the seventh element of the control code the office track-indication relay AK is connected to contacts of relays TC and TO, one of which was energized by the first pulse of the code and the contacts of this relay are moved