GB781738A - Multiswitch on the cross-bar principle - Google Patents

Abstract

781,738. Electric selectors. STANDARD TELEPHONES & CABLES, Ltd. Aug. 19, 1955 [Aug. 25, 1954], No. 24007/55. Class 40 (4). A cross-bar switch comprises a frame carrying a number of single switches, each of which comprises a number of cross-points and each of which is detachable from the cross-bar switch without affecting the remaining parts of the cross-bar switch. A single switch or horizontal level of cross-points is shown schematically in Fig. 1 together with the associated operating mechanism. Considering the left hand unit only, operation of armature 5 by its upper or lower magnet lowers or raises rod 7 to raise or lower spring finger 11. Subsequent movement of the bar 14 of that level to the right carries along member 15 which traps the finger 11 against the upper or lower card 4 to push two sets of contact springs 3 against the vertical contacts 16, only two of which are shown in Fig. 1. One of the two sets of connections is selected electrically by auxiliary contacts (Figs. 13-15, not shown). The magnet associated with armature 5 may be released but the connection is maintained until the rod 14 is returned by the release of magnet 23 (Fig. 4, not shown). Each level has a frame 26, Fig. 5, attachable to the main frame. The movable contact springs are inserted through slots 29, the ends of the springs being soldered or welded to vertical multiples 21, Fig. 2, at points 39 (also Fig. 11, not shown). The turned-up flaps 30 act as stops for the cards 4. The horizontal operating-rod 14 and fixed contacts 16 are supported by an auxiliary frame, Fig. 6, which is secured to the level frame 26, Fig. 5. The fixed contacts 16 in one level are multipled (Fig. 3, not shown). The cards 4 are made of flexible material, Fig. 9, to allow ready engagement of the contact springs 3. The bar 7 has a pair of fingers 61, 62, Fig. 16, engaging a strip of non-abrasive plastic material for damping purposes..