GB237447A - Improvements in selector switches - Google Patents

Abstract

237,447. Western Electric Co., Ltd., (Western Electric Co., Inc.). Sept. 9, 1924. Automatic exchange selectors.--Rotary line switches &c. without feed brushes have a terminal bank made up of rows of separate terminals 5 alternating with continuous strips 6 constructed so that a level composite surface is provided for the wipers. The wipers are of the form shown in Figs. 1 and 2 and move 'between the strip and the terminals, or as shown in Fig. 4, the wipers may have two arms 37, 38 embracing a strip and row of terminals. The prongs that make contact with the terminals may be wide enough to bridge the space between the terminals. To ensure continuity of contact while minimizing the additional load when one set of wipers is passing off and the other on to the bank, the strips are extended at either end beyond the last terminal. The same result is achieved in the switch shown in Fig. 4 by staggering the arms 37, 38 of the wipers. Alternatively the different wipers may be staggered. The bank is moulded in one piece or in sections and is secured between end-plates 4 by means of screws 8 and mounted on the frame 1 carrying the wiper shaft 9 and stepping magnet 13. The armature 15 is pivoted at 16 and retained in the position shown by a spring 20, the tension of which is adjusted by means of the arms 21, 22. The stepping pawl 18 and interrupter springs 28 are operated by an extension 17 of the armature. A stop 23 prevents over-drive.