GB1503916A - Electrical switch - Google Patents

Abstract

1503916 Actuation of switches LUCAS ELECTRICAL Ltd 13 May 1975 [8 June 1974] 25552/74 Heading H1N A "push-push" switch having a manually operable three-position slider which is urged to a first position by resilient means and retainable in the second and third positions by latch means upon slight return movement of the slider after movement beyond said positions respectively, and which is released to return from the third position by further movement beyond said position, has resistance means to provide a discontinuity in feel whereby the operator can recognize that the slider has reached a position whereat it will latch in the second position when released. Two embodiments are disclosed, each having a pin cooperating with a track of doubly re-entrant type to provide latching in the second and third positions of the slider, and a spring-loaded ball carried by the slider to provide the resistance indicating its second position. In the first embodiment (Figs. 1 to 3, not shown) the ball (29) runs in a groove (32) in a casing (11) between first and second positions and has to be depressed against its spring loading to attain the third position. In the second embodiment the latching track is formed in a pivoted plate (34, Fig. 4, not shown) which pivots into the path of the ball (37) when the slider is moved to its second position. In both embodiments movement of the slider directly from its first position to its third position entails overcoming the resistance of the ball (29, or 37) but in the second embodiment an alternative track is provided in the metal plate such that it is not sufficiently pivoted to obstruct the ball when the slider is moved to its third position from its second position.