Patent GB-766179-A (GB)
Title: Railway route-establishing equipment
IPC: B61L19/06
Filed: 1952-05-09
Abstract: 766,179. Railway route setting apparatus. STANDARD TELEPHONES & CABLES, Ltd. May 9, 1952 [June 16, 1951], No. 11789/52. Class 105. A railway route composed of component route sections or paths in respective portions of a railway junction, each portion comprising a network of track switches, is established by connecting electrically in series path establishing devices such as latch relays (path relays) for establishing each path in the route. When a number of paths terminate at a common line, the path relays are operated over a circuit including a normally closed contact of each of the path relays so that operation of one path relay renders the others inoperable. A " direction " relay is operated to indicate direction of travel over a two-way track common to several routes in a circuit including a normally open contact of a path relay for a path forming part of a route terminating in the common track and a normally open contact of a path relay of another portion of the junction. When a group of paths in one portion terminates at a common track leading to another portion, a " group " relay operates before any path relay of the group and a normally closed contact of each such path relay is included in the operating circuit of the group relay to prevent the simultaneous operation of two path relays, and the operating circuit of a path relay in one portion includes a contact operable by a group relay in another portion. Each path relay is slow releasing. To establish a route for a train arriving at platform 5, Fig. 1, from the two-way running line Ma, the arrival control key a for the line Ma and the control key 5 for the platform 5 are operated. The path relay FS103/Ma, Fig. 2, for the path from line Ma to track 103 in portion I of the junction, and the path relay FS103/5 for the path from track 103 to platform 5 in portion II are operated in series. The path relays FS in Fig. 2 are arranged according to the paths which terminate at a given line. For example, the relays FS1/Ma, FS102/Ma, FS103/Ma of the three paths in portion I terminating at the running line Ma, are energized over a common circuit which includes a contact of each of the relays, viz. fs1/Ma, fs102/Ma, fs103/Ma, shown as change-over contacts. Leads from relays relating to paths terminating at the same track or platform line are commoned and a normally closed contact of each of these relays is included in the commoned lead. For example, leads from relays FS1/Ma, FS1/b, FS1/Bl of the three paths terminating at platform 1 have in the commoned lead normally closed contacts fs1/Ma, fs1/b, fs1/Bl. The path relays in the lower portion of Fig. 2 for the paths of portion II are similarly arranged. The commoned lead for path relays of portion I which terminate at any one track is connected directly to the commoned lead of path relays in portion II which terminate at the same track. For example, the commoned lead from relay F3103/Ma is connected directly to the commoned lead for relay FS103/2. On operation of the change-over contact fs103/Ma its front contact is closed in lead 1 to which the circuit, Fig. 4, is connected, key contacts a, Figs. 2 and 4, and 5, Figs. 2 and 4, being already closed, and relay FS103/5 having pulled up in series with relay FS103/Ma, " directional " relay FSE/a, Fig. 4, thus operates and is used to determine the direction of travel. Platform lines 6, 7, 8 in portion III can only be reached over the track 106, Fig. 1. To set up a route, say from the running line Ma to platform 7, the arrival control key a for the line Ma and the control key 7 for platform 7 are operated thereby operating the series-connected path relays FS103/Ma and FS103/106, Fig. 2, and the " group " relay 6-8, Fig. 3, the circuit of which is connected at the dotted line shown below relay FS103/106 in Fig. 2, provided no conflicting paths in any portion of the junction have been established. At the front contact 6-8 in the circuit of series-connected relays FS103/106 and FS103/Ma, Fig. 2, a holding circuit is provided for these relays. On the closure of contact fs103/106, Fig. 3, relay FS106/7 is operated establishing the path 106/7 and opening the contact fs106/7, Fig. 3, and closing contact fs106/7, Fig. 4, to operate the directional relay FSE/a through a front contact 6-8 of the group relay. To prevent the premature release of either of the two series-connected path relays such as FSa and FS1, Fig. 5, each relay, in addition to its main pick-up latching winding (not shown) is provided with a release winding I in series with an auxiliary operating winding II which tends to keep the relay operated and across which is connected a normally open contact fsaI, fs1I closable by energization of the release winding I to short-circuit the winding II and allow the relay to release.