Patent GB-545408-A (GB)
Title: Improvements in systems for the remote control of railway track switches and signals
IPC: B61L19/06
Filed: 1939-12-04
Abstract: 545,408. Railway route-setting apparatus. GENERAL RAILWAY SIGNAL CO. Dec. 4, 1939, No. 31418. Convention date, Dec. 13, 1938. [Class 105) Railway route-setting apparatus of the entrance-exit button type and having lock relay means to prevent change of points setting when a train is approaching or passing through is such that on briefly depressing an entrance button electric-circuit lines are set up corresponding to the points trailed in all routes emanating from the particular entrance point which are not in conflict with any route already cleared for entry of a train and thereafter on briefly depressing the desired exit button points control relays are energized in sequence from the exit end to set the various points to the required settings. Where there are no intermediate signals in the route set up this is described'as an interlocked group. Where a route is set up through two or more such interlocked groups this is described as a. through route and there is an intermediate signal provided by the entrance signal at each successive interlocked group. Where alternative routes are possible the crossover most remote from the entrance signal is pre-selected as the one to be operated to reverse setting. If however this crossover is at any time locked in its normal setting then a preceding crossover is utilized. The system is arranged so that though shunting operations may be carried out in directions against 'the normal direction of travel along a track a through-route signal clearance cannot be effected in the direction opposite to the normal direction of traffic along a track. To set up a route from signal 14 to signal 17 which is an " interlocked " group, i.e. one having no intermediate signal, the operator first briefly depresses entrance button 14 NB, Fig. 1C, to close a circuit from +ve. over depressed contact 35, wire 83, back contact 36 of relay 12NR, wire 84, and front contact 37 of track relay 8T, to winding of relay 14NR. Relay 14NR remains energized by a stick circuit over its contact 38 when the button 14NB is released. Front contact 39 of relay 14NR then applies +ve. over back contact 40 of relay 14XR to two lines leading over various contacts to the exit buttons 16XB, 17XB of the two possible routes emanating from the entrance signal 14, and when the button 17XB is briefly depressed, relay 17XR is energized over that line from back contact 40 comprising back contact 41 of relay 4AN, back contact 42 of relay 4BN, back contact 43 of relay 4BY, winding of relay 17XR, and back contact 44 of relay 17NR. On release of exit button 17XB the relay 17XR remains energized over its stick contact 46. Front contact 47, Fig. IF, thereupon applies +ve over back contact 48 of relay, 4BY to the upper winding of relay 4R whereby the crossover 4TSA-4TSB, Fig. 2, is set to its reverse position under the control of polar relay 4WZ reversely energized from +ve, over contacts 28, 29 of lock relays 8L, 9L, front contact 55 of relay 4R and lower winding of relay 4WZ. The signal 14 is now cleared by its signal relay 14G becoming energized over front contact 72 of relay 17XR, back contact 73 of stick relay 4LS (dropped when the crossover points completed their movement), back contact 74, front contact 75, back contact 76, of correspondence relays 4NCR 4RCR in the state denoting the crossover points 4TSA-4TSB locked at reverse, back contact 77 of relay 4LS, back contact 78 of relay 14XR, and front contact 79 of relay 14NR. If instead of entrance button 14NB the entrance button 15NB had been actuated then relay 15NR would have been operated and the relay 4 BY would have been picked up over front contact 51 of relay 15NR, back contact 52 of relay 15XR, and back contact 53 of relay 4R before extending this line over its own front contact 43 to the relay 17XR and exit button 17XB. It will be noted that with relay 4BY thus energized the open back contact 43 thereof would prevent the line from front contact 39 of relay 4NR through back contact 40 of relay 14XR being completed to the relay 17XR. Moreover with relay 4BY now energized the front contact 47 of relay 17XR applies +ve over front contact 48 of the relay 4BY to the upper winding of relay 4BN whereby the control relay 4WZ is energized to set the crossover 4TSB-4TSA to normal. Cancellation of a set-up route such as 14-17 is effected by pulling out the entrance button 14NB to break the stick circuit of the relay 14NR which in turn breaks the stick circuit of the relay 17XR by opening front contact 39 of the relay 14NR. Entry of a train past the signal 14 drops the track relay 8T to open its front contact 37 in the stick circuit of the relay 14NR which in turn drops its front contact 39 to open the stick circuit of the relay 17XR. The signal 14 goes to danger by the dropping of front contact 79 of the relay 14NR in the circuit of the relay 14G. It should be noted however that the relay 4R remains energized by its middle winding Fig. 2 receiving current first over back contact 85 of relay 8L and then over back contact 89 of relay 9L. It should also be noted that a back contact 214 of a repeater relay 8TP for the track relay 8T allows the relay 14NR to be picked up preparatorily for setting another route while the train is still in section 8T. When it is desired to set up a through route through a number of " interlocked " groups so that there are intermediate signals in such route, e.g. the through route from signal 16 to signal 11 which includes intermediate signal 12, then the appropriate end buttons are actuated. Brief depression of entrance button 16NB picks up relay 16NR over front contact 92 of track relay 8T ; relay 16NR then sticks by its contact 93. Contact 94 of relay 16NR thereupon picks up relay 4AY over back contacts 95 of relay 16XR and 96 of relay 4R (crossover 4TSA- 4TSB not being put to or held at reverse). Front contact 97 of relay 4AY extends the +ve potential through back contact 98 of relay 14XR, over front contact 101 of track relay 8T and front contacts 99, 100 of correspondence relay 4NCR and track relay 9T, in parallel, wire 102, contact 103 of signal-at-danger relay 12M, back contact 104 of relay 12N R, back contact 105 of relay 12XR, back contact 106 of relay 3R, back contact 107 of relay 3AY, wire 108, back contacts 109, 110 of relays 2BN, 2AN, back contact 111 of relay 2BY, to relay 11XR and back contact 112 of relay 11NR to exit buttons 11XB which on brief depression picks up the relay 11XR the latter then sticking over its contact 114. The closure of front contact 115 of relay 11XR applies +ve over back contact 116 of relay 2BY to bottom winding of relay 2R to set crossover 2TSB-2TSA at reverse. Front contact 119 of relay 2R extends this potential to wire 120, back contact 121 of relay 3AY, and so to bottom winding of relay 3AN which sets crossover 3TSA-3TSB normal and at its front contact 123 energizes relay 12XP over back contact 124 of relay 12NR to -ve. Relay 12XP continues energized through its own front contact 126, wire 127, and back contact 128 of relay 14XR to -ve when relay 12NR is picked up by the closure of front contact 130 of relay 12XP. With relays 11XR, 12NR thus energized the intermediate signal 12 is cleared since the signal relay 12G is energized, Fig. 3 A, from +ve, over a front contact of relay 11XR, back contacts of relays 2LS, 2NCR, a front contact of relay 2RCR denoting crossover 2TSB-2TSA set reverse, a back contact of relay 3LS, front contact of relay 3NCR denoting crossover 3TSA-3TSB set normal, a back contact of relay 12XR and a front contact of relay 12NR It should be noted that the opening of front contact 103 of the signal-at-danger relay 12M does not drop the relay 11XR since front contact 104 of the relay 12NR is now closed. Front contact 217 of relay 12XP maintains the line to the relay 11XR energized during the lifting of contact 104. With relay 12XP closing its front contact 140 and relay 12NR closing its front contact 139 -ve potential is applied over back contact 138 of relay 12XR, wire 137 and back contact 136 of relay 14NR to the left hand side of relay 14XR which is thereupon energized since its right hand side has +ve applied. With relays 16NR and 14XR thus energized the crossover 4TSA-4TSB is put to or held at normal and the signal 16 cleared in a manner similar to that already described. The relay 14XR by opening its back contact 128 removes -ve from the relay 12XP which therefore drops. Relay 12XP is slow dropping to ensure that its contact 140 will remain up a sufficient time for relay 14XR to close its stick contact 141 after contact 128 of relay 14XR opens. If more than one route is possible between the end points of a through route one route is given preference. Thus if a route between signals 17 and 10 us set up the crossover 3TSB-3TSA is used in preference to the crossover 4TSB-4TSA. With relay 17NR energized (by brief depression of entrance button 17 NB) to close its contact 144 +ve is applied over back contact 145 of relay 17XR, back contact 146 of relay 4R, back contact 147 of relay 15XR, front contact 148 of track relay 9T, wire 149, contact 150 of signal-at-danger relay 13M, back contact 151 of relay 13NR, back contact 152 of relay 13XR, and back contact, 153. 154 of relays 3BN, 3AN to relay 3AY. When exit button 10XB is briefly depressed a circuit is completed from +ve over front contact 144 of relay 17NR, back contact 145 of relay 17XR, back contact 146 of relay 4R, back contact 147 of relay 15XR, front contact 148 of track relay 9T, wire 149, front contact 150 of signal-at-danger relay 13M, back contact 151 of relay 13NR, back contact 152 of relay 13XR, back contacts 153, 154 of relays 3BN, 3AN, front contact 107 of relay 3AY, wire 108, back contact 155 of relay 2R to relay 10XR, and over back contact 156 of relay 10NR to -ve ; relay 10XR continues energized over its stick contact 158. The closure of front contact 159 of relay 10XR applies +ve to bottom winding of relay 2AN (to set