Patent GB-646365-A (GB)
Title: Devices for registering the telephone numbers of lines in automatic telephone systems
IPC: H04M15/04
Filed: 1946-02-27
Abstract: 646,365. Automatic exchange systems. TELEFONAKTIEBOLAGET L. M. ERICSSON. Feb. 27, 1946, No. 6156. Convention date, Feb. 28, 1945. [Class 40 (iv)] In a cross-bar system the number of a calling subscriber at a satellite exchange is registered in terms of the operating and selecting magnets operated, and the information is transmitted in known manner to a main exchange where it is employed by a ticketing machine (not described). The receipt of an identification start signal over the junction results in the re-operation of the line relay of the calling line which initiates the identification. Operation. As shown, line relay LR pulls up to the calling loop over La, Lb and, providing the marker (Fig. 3) is not in use on another call, R41 operates in a circuit over wire l2 common to ten subscribers, and R31 over an individual wire l3, followed by R1 which energizes one of the selecting magnets SM1-10, say SM10, and the operating magnet FM of one of the main exchange junctions Fa, Fb which brings up the operating magnet LM of the calling line so that the calling loop is extended to the junction and operates a current feeding relay therein (not shown) as a result of which R22 comes up to hold FM and LM and bring up UR to mark the link a, b, c, d busy. The operation of FM releases R1 and that of LM, LR followed by R41 and R31 in the marker. The calling party dials the required number and the impulses are repeated over the junction by the current feeding relay. Calls requiring ticketing. On these calls a signal is reverted over the junction from the main exchange and results in the application of positive battery to the wire Fc bringing up R23. If the marker is free, R3 and R24 come up, disconnecting the normal operating circuits of all the subscribers' line relays and operating that of the calling party over wire d, whereupon the marker is again taken into use and R41 and R31 are re-operated. With R3 up, this results in the energization of R4 to seize a register (Fig. 4) in which relay RR4, the selecting magnet corresponding to the tens digit of the calling line, in this case SM11, and operating magnet RM1 operate. The resulting operation of RR5 releases RR4 and brings up R2 in the marker which opens the original operating circuit for SM11. RR5 also operates the selecting magnet corresponding to the units digit of the calling line, in this case SM11 over a wire such as m1. Consequent upon the release of RR4, operating magnet RM2 is energized and holds in parallel with RM1 under control of RR5. In the register sender RS (Fig. 4), the selecting magnet SM20 corresponding to the junction in use, is thereupon energized, and is followed by the operating magnet RM3 which releases RR5, takes over control of RM1 and RM2, and brings up R21 (Fig. 2). The last relay releases R23, whereupon R24, SM20 and LR (Fig. 1) fall away, the last relay releasing the marker. RM3 meanwhile holds under control of R21, R22. The register then transmits impulses corresponding to the calling number registered by RM1, RM2 over wires g1 and Fd to the junction over which they are repeated in known manner. At the completion of impulsing the removal of positive battery from RM3 initiates the release of the register.