Two-stage multiplex switching system employing interlaced connections between highways and external circuit groups

摘要

957,252. Automatic exchange systems. NIPPON ELECTRIC CO. Ltd. Aug. 7, 1962 [Oct. 14, 1961], No. 30244/62. Heading H4K. In multiplex telephone switching system having a plurality of highways H1 . . . H5 interconnected by links such as H12, groups of subscribers or junctions S1 . . . S5 are connectible to more than one highway. Thus in the T.D.M. system shown in Fig. 5, each subscriber of a group S1 may be connected via pulsed gates (not shown) to both highways H1 and H5. The number of highways is less than twice the number of groups of subscribers or junctions. The arrangement allows continuous service in spite of the breakdown of a highway or link, without the necessity of extensive duplication. In a modification (Fig. 8) the highways are divided into groups, and withingroup highways such as Hg11 and intergroup highways such as Hg12 are provided. Each subscriber/junction group S11 (say) has access to highways such as H11, H21 in adjacent groups.