Patent GB-683881-A (GB)
Title: An automatic telephone or telegraph system
IPC: H04Q3/00
Filed: 1948-05-03
Abstract: 683,881. Automatic exchange systems. COMPAGNIE INDUSTRIELLE DES TELEPHONES. May 3, 1948 [July 11, 1947], No. 12111/48. Class 40 (iv). In a system having connectors serving P.B.X. groups similar to that described in Specification 668,261, the lines of a P.B.X. group may be connected non-consecutively in the banks of the connectors. First arrangement, Fig. 1. Each register ER1 is provided with an individual battery (indicated in Fig. 1 by +, -) and a sequence switch controlling the various operations. Assuming that the tens and units register switches X5, X6 have been respectively set by the dialled digits to positions 4, 9 corresponding to line 1, that the sequence switch is in position a7 ... e7 and that relays 2, 3, 4 are operated, the driving magnet CO1 steps the connector CO to line 1, whereupon a control relay 6 is operated. If line 1 is free, the upper winding of relay 5 is energized in opposition to its previously energized lower winding and relay 5 falls back to connect up relay 7 which shunts out the lower high resistance winding of relay 6 to allow a marginal relay 1 to switch the call through. Otherwise, sluggish relay 12 pulls up to cause busy tone to be reverted. Should the line 1 be the first of a P.B.X. group, its wire s is connected together with those of the first lines of other groups to a common lead multipled to the registers, and relay 11 is energized by the register battery to operate relay 10 which allows relays 11, 12 to fall back. The magnet R steps the sequence switch to position a8 ... f8 and disconnects relay 6 from the units register switch X6. The connector CO again moves on, and, assuming the P.B.X. lines are busy, passes to the last consecutive line 4 of the group over the intermediate lines 2, 3. The wires s of all intermediate consecutive group lines are connected to a common lead multipled over make contacts of relays 10, 7 to the control relays 6 of the registers. If line 4 is also the last line of the group, its wire s is commoned together with those of the last lines of other groups consisting only of consecutive lines to the register leads DL, and relay 11 connects up the busy relay 12. Otherwise, a circuit is completed over bank b of the tens switch X5 for relay 9 to lock up and to leave the control relay 6 dependent on a circuit formed over bank b and a lead commoned to the wires s of the remaining lines of the group. The connector rotates, relay 6 releasing on non-wanted lines, e.g. 5, until relay 11 is connected up over bank c and a lead to the wire s of the last line 6 of the group and operates followed by the busy relay 12. If there is a second P.B.X. group in the same decade, its lines are marked over banks d, e of X5 and relay 8 takes the place of relay 9. Second arrangement, Fig. 2 (not shown). This is similar to the first, but the common leads for consecutive intermediate lines and for the last lines of groups comprising only consecutive lines are dispensed with. The wires s of all lines other than the first and last are connected to the relevant contact of bank b of the tens switch X5. Thus when the connector reaches the second line relay 9 is operated and the hunting is then continued as described above. The Specification as open to inspection under Sect. 91 comprises also a third arrangement, Fig. 5 (Cancelled), in which a marking circuit is provided for each switching stage. The marking circuit COC2 for the connector CO2 includes a switch CC having banks a ... g each divided into four segments with intervening normal positions, the numerals following the references a ... g indicating in which segments each bank is effectively connected up. When the connector CO2 and the marking circuit COC2 are seized, relays 13, 19 pull up and relay 21 is connected up over the normal contacts of bank o. The impulses of the penultimate digit, e.g. 4, are repeated by relay 20 to the magnet CC which steps the marker switch CC. Relay 21 falls back and magnet CR steps the connector to the first line of the wanted decade marked over bank a. Test relay 15 closes a circuit for 18 and the marker switch CC moves to its next normal position, whereupon dialling relay 21 re-operates. In response to the final digit, e.g. 4, the switch CC marks the wanted line 3 over bank d. The rotation of the connector is again stopped by the operation of the test relay 15 and relay 16 pulls up to energize a slow-operating busy relay 17. If the line 3 is idle, relay 14 switches through. The wire s of the first line of the wanted P.B.X. group is connected to relay 22. Thus, supposing line 3 is a first line and is busy, relay 22 locks up to disconnect the test relay 15 and the connector rotates. The wires s of the intermediate lines of the group are commoned to the relevant contact of bank f, and the rotation of the connector is not stopped unless the double test performed by relay 14 (i.e. for idle and wanted group conditions) is successful, until the last line 11 is reached, whereupon a circuit is completed over the wire s for relay 15 to connect up relay 16 and the busy relay 17. This subject-matter does not appear in the Specification as accepted.