Patent GB-557931-A (GB)
Title: Improvements relating to route control apparatus for railways and the like
IPC: B61L19/06
Filed: 1942-06-09
Abstract: 557,931. Railway route-control apparatus ; electric switches. WESTINGHOUSE BRAKE & SIGNAL CO., Ltd., and PETER, L. H. June, 9, 1942, No. 7398/41. [Class 105] [Also in Groups XXXVII and XXXVIII] In a route control system of the kind described in Specification 550,685 in which each desired operation such as the operation of a point or signal or the setting up of a route is identified with a code number and the selected operation is initiated by dialling in succession the digits composing the appropriate code, the dial transmitter of telephone type is arranged to effect the operation of a stepping selector of known type which controls the energization of digit relays. The cancellation of a set-up route &c. in several ways is described, in one of which by the use of an additional contact bank of the selector in conjunction with special relays the route may be cancelled by dialling the route code number a second time. The Specification traces in detail the operation of energizing the first digit relay of the code number, energization of the remaining digit-relays of the code number being effected similarly. The description assumes the selective setting up of a route 505. The arrangement shown comprises normallyclosed contacts DC operated by dial, not shown, in the ordinary way to open contacts DC when he dial is moved from normal position and reclose them on return movement a number of times depending on the position to which the dial was moved, viz. five times in dialling the first digit of the code 505. The arrangement also includes a relay R, with front and back contacts R1 closing respectively the circuits of stepping magnet SM and a slow-release relay SR, selector contact banks E, F, G slow pick up relays D, DS, homing stick relays 1HS, 2HS, 3HS successively energized after dialling the first, second and third code digits, respectively, and a bank of digit relays. This bank comprises thirty digit relays, viz. ten for each digit of the three-figure code described but only digit relays 1-5, 2-5, 3-5, 1-0, 2-0, 3-0 concerned in dialling the digits 5, 0 included in the code 505 are shown. When the dial is operated to dial 5, the first digit of the code, initial opening of contacts DC de-energizes relay R and relay SR picks up over back contact R1, and remains picked up by subsequent closures of back contact R1 as the dial returns, this return movement closing contacts DC and energizing magnet SM five times over front contact R1. Each de-energization of magnet SM after being energized moves selector.bank contact arms 1, 2, 3 one step in known manner. Initial movement of arm 1 picks up relay D, followed by the picking up of relay DS over contact D1 and the breaking of the circuit of relay D at contact DS1. The action of these relays is slow enough to ensure that dialling is completed, and arm 2 rests on contact 5 of bank F, before they operate. Before relay D releases, circuit is closed over front contact D2, arm 2 and contact 5 of bank F, back contact 1HS2 of homing stick relay 1HS, continuity contacts C(1-5) and winding of digit relay 1-5 which closes its stick circuit over contact C(1-5) back contact 3HS2 of relay 3HS and normally closed contacts RE (2) of a resetting button RE. Contact 1-5(1) then closes a circuit over contact group SC to cause magnet SM to return the selector contact arms to home position in the known manner. Contact 1-5(2) then closes the circuit of relay 1HS over arm 3 of bank G in its home position and relay 1HS closes its stick circuit over contact 1HS3. The arrangement finally restores to normal except that relays 1-5, 1HS remain energized. When the second digit 0 of the code is dialled, the parts return to normal except that relays 2-0. 2HS remain energized. After dialling 5 for the third digit of the code, relays 1-5, 2-0, 3-5, 3HS remain energized, the relay 3HS breaking the stick-circuits of relays 1HS, 2HS at contacts 3HS 4, 3HS6. Front contacts 1-5(6), 2-0(6), 3-5(6) of the energized digit relays are included in series in the circuit of the route relay 505RS, Fig. 2, together with interlocking arrangements for other routes indicated at RS. Assuming these closed, relay 505RS is energized and close its stick circuit over contact C505RS assuming the circuit indicated at TCR is closed. TCR may include track-relay contacts which open when the corresponding track sections become occupied, and may include other cancelling arrangements as described below. When relay 505RS picks up its front contact 505RS1 connects source line SL to a line RL leading to apparatus for setting the signals &c. for the selected route, and when it releases, back contact 505RS1 connects SL to line NL for restoring signals &c. to normal position. Front contacts 505RS2 closes circuit through a route lamp 14. Before relay 505RS is energized the arrangement shown in Fig. 1 may be restored to normal at any stage by operating resetting button RE, contacts RE1, RE2, RE3 opening to break the' stick circuits of relays which may have been energized and contact RE4 closing to complete a circuit through contacts SC and magnet SM to restore the selector to home position. After relay 505RS has picked up it may be de-energized by any suitable cancelling device included in its stick circuit at TCR. The Specification refers to a rotary switch which may be moved to any of a number of angular positions and then plunged to break circuit, each position corresponding to a route, or to a number of routes having a common entrance. Or separate cancelling buttons may be provided, for example one for each direction of traffic. Fig. 4 shows a button suitable for mounting on the panel 21 in which a slidable member 19 carries the lamp 14 showing through a pane 22 in the button head, the member 19 being biased to the left by spring 26 its movement outwards being limited by a wedge member 27 on a stem carried by member 19. The lamp circuit is completed through contacts 23, 24 and normally closed contacts 25 are included in the circuit at TCR, Fig. 2. All these contacts are broken when the button held is pressed inwards. Fig. 3 shows an arrangement by which cancelling is effected by dialling the code number a second time. In addition to the arrangement of Fig. 2, some only of which is shown, it includes an additional selector contact bank H with arm 15 closed only in home position, slow-release relays 505NR, 505RC and additional digit relay contacts. When 505 is first dialled and digit relay contact 3-5(6) closes, relay 505RS energizes and closes its stick circuit over contact C505RS as already described at the same time breaking circuit between contact 3-5(6) and relay 505RS. When in due course the digit relays release, back contacts 1-5 (7), 2-0(7), and 3-5(7) close and relay 505NR picks up as contact 505RS3 is closed and closes its stick circuit over contact 505NRI. When 505 is dialled a second time and contact 3-5(6) closes, relay 505RC is energized over contact 505NR2 and closure of its contact 505RC1 shunts relay 505RS over arm 15.