Patent GB-814481-A (GB)
Title: Exit line indicating apparatus for a railway junction
IPC: B61L19/06
Filed: 1956-09-07
Abstract: 814,481. Exit line indicating apparatus for a railway junction. STANDARD TELEPHONES & CABLES Ltd. Sept. 7, 1956 [Sept. 13, 1955], No. 27466/56. Class 105. In setting up,routes through a railway junction having a plurality of exit lines and at least one entrance line each exit line is assigned a code which when a route has been set up between an entrance and exit line, is transmitted to code receiving apparatus to effect an indication on an exit line indicator associated with the entrance line so as to indicate the exit line out of the junction which has been lined up with the entrance line. The code transmission circuit includes a contact for each position of each points used in establishing the route through the junction, each contact closing when the points associated therewith is locked in the position required for the route. The codes may consist of A.C. and D.C. potential and there may be more than one code transmission circuit for each route. The code transmission circuit may also be utilized to operate e.g. a distant signal to correspond to the aspect displayed by another signal, e.g. a home or starting signal ahead. For a through route established from the home signal A, Fig. 1, through the station track 1 to the main departure line M the points 7 and 9 will be set to the normal position (+) and locked in that position so that contacts 72+, 73 and 92+ shown in the control circuit, Fig. 2 (which like Figs. 4, 6, 7 simulates the track diagram) and associated with the locking of the points 7, 9, are closed to complete a circuit for an auxiliary relay 1H over the contacts MP2 (of a test relay MP, Fig. 6, for code reception relay M), MU1 of a switch-over relay MU, Fig. 6, 92+, 72+ and dUl of a switch-over relay associated with the distant signal d, Fig. 1. A.C. is applied thus to the relay 1H which picks up when energized by A.C. or D.C. energy. At f.c. 1H1 (front contact 1 of relay 1H) the A.C. relay 1M is energized over its winding I and condenser K3 indicating at track 1 reception of the A.C. code from track M. Relay 1M holds over f.c. 1M2 and its second winding 1MII, over f.c. 73 and resistance Wi2. At f.c. 1M1, Fig. 6, relay MP is energized over contacts f.c. 93, 91+, 71+ and b.c. dU2 (back contact 2 of the switch-over relay dU). At b.c. MP2, Fig. 2, relay 1H is de-energized and drops away to open contact 1H1 in the energizing circuit of code-receiving relay 1M which is held by its winding II. At b.c. 1H2, Fig. 2, a circuit is completed for energizing relay dU in series with windings II of relay 1M. At b.c. dU2, Fig. 6, the pick-up circuit of relay MP is broken but this relay is maintained energized in series with switch-over relay MU over f.c. MP1. At f.c. dU1 and MU1, Fig. 2, one of the two distant signal control relays dl, d2 is picked up depending upon the position of the contacts D1, D2 which in turn depend on the setting of the main signal D, Fig. 1, At f.c. d11 or d21, Fig. 3, there is switched on the distant signal lamp dL1 or dL2 which lamps are located at the starting signal B and will indicate there the position of the main signal D. When lining up the entrance track a with the station track 1 points 4 and 5, Fig. 1, are in the normal (+) position. An A.C. energizing circuit for auxiliary relay RH, Fig. 4 (which responds to A.C. or D.C.) is completed over f.c. IM3, b.c. 1P2; b.c. 1U1; f.c. 52+, 42+, b.c. bU1. At f.c. RH1 the A.C. code reception relay RM is energized over its winding I and condenser K1 and at f.c. RM2 completes a stick circuit over its winding II over f.c. 43 and resistance Wi1. At f.c. RM3 the lamp RLM, Fig. 5, of the exit line indicator R, Fig. 1, is energized to indicate that the route from a to M has been established through track 1. At f.c. RM1, Fig. 7, test relay 1P of the code reception apparatus for track 1 is energized over f.c. 53+, 51+, 41+ and b.c. bU2 and at f.c. 1P1 prepares a stick circuit for itself in series with relay 1U. At b.c. 1P2, Fig. 4, relay RH is deenergized. At b.c. RH2 switch-over relay bU is inserted into the stick circuit of relay RM winding II. At b.c. bU2 the short-circuit across relay 1U, Fig. 7, is removed and this relay picks up in series with relay 1P, contact 1P1 being already closed. At f.c. 1U1 and bU1, Fig. 4, signal control relay b1 or b2 for distant signal b at signal A is energized depending upon the position of contacts B1, B2 associated with the starting signal B, and this latter having been finally set at " clear " for the route under consideration, contact B1 is closed, to provide an energizing circuit for relay b1. At f.c. b11, Fig. 5, the lamp bL1 of the distant signal b indicates the clear aspect of the starting signal B.