Patent GB-483065-A (GB)
Title: Improvements in or relating to electrical switches, torches, and the like
IPC: H01H13/22
Filed: 1936-07-02
Abstract: 483,065. Retractive switches. EVER READY CO. (GREAT BRITAIN), Ltd. July 2, 1936, No. 18427. Void. Convention date, Aug. 10, 1935. [Class 38 (v)] A switch, particularly suitable for a battery lamp, comprises co-operating contacts mounted in a housing, and means for moving one of the contacts into engagement with the other, said means comprising a finger-piece that is both rockable about an axis and bodily translatable. In the construction shown in Figs. 1 and 2, the contacts 10, 12 are enclosed in a housing 16 secured to a flashlamp casing 18, the contact 10 being in the form of a resilient switch-blade, while the contact 12 normally occupies a position in the path of the contact 10, but can be moved out of this path, to render the switch inoperative, by means of a button 34 slidably mounted in the housing. The switch is operated by a finger-piece 14 having a central portion 36 of circular outline, the outer part of which extends through an opening 38 in the housing, while the inner part engages the switch-blade 10, and arcuate portions 40 on each side of the central portion. The inner portion of the finger-piece engaging the switchblade is formed with a depressions 44 co-operating with a projection 46 on the switch-blade. The contacts 10, 12 can be brought into temporary engagement by depressing the fingerpiece, or bv rotating the finger-piece so that the projection 46 leaves the depression 44 and engages the surface of the portion 36, the contacts can be held in engagement with each other. To prevent excess pressure on the finger-piece from injuring the switch, the inner movement of the finger-piece is limited by the engagement of the arcuate portions 40 with the sides 54 of a groove 52 which receives the contact 10. In a modification, the fingerpiece is provided with two depressions, one deeper than the other. When one projection on the switch-blade engages the deeper depression, the switch cannot be closed by depressing the finger-piece, but by rotating the finger-piece so that the projection engages the surface of the finger-piece between the depressions, the switch can be held in the closed position. In another construction, Fig. 5, the movable switch-blade 72 is carried by a stud 80 mounted in a slot in the housing 74, the switch-blade being provided with a depending ear 84 adapted to make contact with the conductor 70, which is insulated from the casing. The switch may be closed by depressing the finger-piece 88, or it may be closed and held in the closed position by rotating the finger-piece, until a rib 96 on a cam 94 engages a depression 98 in the switch-blade. The switch can be rendered inoperative by sliding the switch-blade to the left by means of the stud 80. In another construction, the finger-piece is provided with a triangularshaped cam, the apices of which are adapted to engage the depression in the switch-blade to hold the switch in the closed position. In the construction shown in Fig. 11, the fingerpiece 131 carries cams 136 and bosses 138, the latter being adapted, in certain positions of the finger-piece, to engage abutments 140 on the base 142 and prevent closure of the switch. The finger-piece is mounted on trunnions slidable in vertical grooves in the housing 127, and has three pairs of operating positions, i.e. two positions in which the switch is closed. two in which it can be closed by depressing the finger-piece, and two positions in which closure of the switch is prevented. In a modification of this construction, the finger-piece is provided with an additional pair of lugs which, in the inoperative position, engage notches on depressions in the switch-blade to lock the latter in this position. A manuallyoperated actuating member is provided to depress the switch-blade and unlock the switch. In another modification, Fig. 20, the fingerpiece 184 is mounted on a trunnion 188 in an opening in the housing 172, and is formed with a cam-shaped end 192. In the position shown, closure of the switch is prevented, but by moving the finger-piece to the position in which the flat surface 192 of the cam engages the switch-blade 166, the switch can be closed by depressing the finger-piece. By rotating the finger-piece still further, the inner end '193 of the cam engages the switch-blade and holds the latter in the closed position. The finger-piece may be provided with projections adapted to engage lugs on the housing to latch the switch in the inoperative position.