GB552224A - Improvements in the remote control of radio receivers - Google Patents

Abstract

552,224. Retractive switches; switches held set and freed mechanically. McDONALD, E. F. July 25, 1941, No. 9460. Convention date, July 25, 1940. [Class 38 (v)] [Also in Group XL] Fig. 2 shows a foot-operated switch comprising a metal base 75 and cover 65 loosely pivoted together at 77, 78 by means of rivets (not shown) and urged apart by a spring 80. Initial movement causes annular contact 93 to engage annular mating contact 68 on an insulating ring 84 urged upwardly by a strong spring 85. Further movement moves ring 84 against spring 85 to allow contact 92 to engage contact 64 for operating the station selecting switch. A modified form of switch is described (Fig. 5) in which upon a partial depression and release, contacts 108, 109 are engaged and held set, a sleeve 102 with spring fingers 104' which engage beneath a plate 106, remaining in the depressed position while the member 96 returns and being then latched relative to the member 96, Fig. 6 (not shown). Subsequent partial depression and release of the member 96 releases the above latch and the parts return to their original position, contacts 108, 109 separating. A complete actuation of member 96 causes contacts 101 and 118 to engage as well as contacts 108, 109, and both sets of contacts are broken when the member 96 is released from the fully depressed position.