Patent GB-652231-A (GB)
Title: Improvements in or relating to control devices for the setting of selectors
IPC: H04Q3/00
Filed: 1946-06-05
Abstract: 652,231. Automatic exchange systems. COMPAGNIE GENERALE D'ELECTRICITE. June 5, 1946, No. 17083. Convention date, July 5, 1945. [Class 40 (iv)] In a system in which access to outlets such as interexchange lines is obtained through a succession of selectors 2, 3, 4, Fig. 1, a registercontroller 9 marks a single wire such as 10 or 11 which is connected to appropriate terminals in the marking banks of each of the successive selectors. All the marking terminals except those of the last selector are connected to all the register controllers by a further wire 12 whose connection indicates that one or more further stages of switching have yet to be effected. The marking wires 10, 11 designate different outlets from selector 4 in whose banks they are therefore connected to different terminals, but in the banks of 2, 3 they are connected to the same terminals since the calls have to be routed through the same succeeding selectors. Effective commoning of the leads 10, 11 is prevented by the insertion of rectifiers therein. The marking multiple is common to all the register controllers, which have individual testing batteries as described in Specification 668,261. Settin the selectors. Fig. 6 shows the relevant portions of the register controller circuits for setting the selectors according to the invention. The marking wire 11 is connected to the selector control circuit over banks of the digits switches X5, X6 when these are set by the digits 22. Relays 1<SP>11</SP> and 2<SP>11</SP> are normally operated at this stage and relay 1<SP>11</SP> starts the first selector. When the latter reaches an outlet of the group marked by wire 10 relay 3<SP>11</SP> operates. If the outlet is free the switch is stopped by the release of relay 2<SP>11</SP> due to the energizing of an opposing winding over test wire T. If there are further selectors to be set according to this marking relay 5<SP>11</SP> operates over wire 12. Relay 4<SP>11</SP> also operates and short-circuits a high resistance winding of 3<SP>11</SP> to operate the switching relay in the selector. Relays 611, 1<SP>11</SP>, 3<SP>11</SP>, 4<SP>11</SP>, 5<SP>11</SP> de-energize in turn, whereupon 1<SP>11</SP> and 2<SP>11</SP> re-energize to start the next selector. When the last of the marked selectors is set 5<SP>11</SP> does not energize and when 4<SP>11</SP> operates the sequence switch X is stepped on to deal with succeeding selection stages. Alternative routing. At any of the selection stages switching means may be provided to connect wire 11 to mark outlets corresponding to an alternative route. The switching may be effected manually or in accordance with the congestion of traffic over a particular group of outlets, e.g. the switching may be effected by a relay which is operated when the number of busy outlets in a certain direction exceeds one predetermined number and released when the number of busy outlets falls to another predetermined number, Fig. 4 (not shown). Determination of the degree of congestion may be effected as described in Specification 23305/46. (as open to inspection under Sect. 91).