GB166446A - Improvements in or relating to electric pushes - Google Patents

Abstract

166,446. Graham, E. A. July 6, 1920. Push-button switches; contacts; bases, boxes, and cases.-Push switches consist of stationary contacts e, e<1> mounted on a two-part insulating base c, c', which is contained within a metal casing b with a back plate a, the movable contact h being carried by a spindle k which passes through the casing b a coiled spring r being interposed between the casing and a dished cover p carried on the end of the spindle k. The cover p moves axially over the casing when it is depressed. The insulating base is formed in two parts c, c<1> secured together by a central screw d, each part having semi-circular grooves on its inner face forming passages g, g<1> for the leads f, f<1>, which pass through holes g<2>, g<3> in the plate c', to be clamped under the screws e, e<1>. The base c, c<1> may be formed at c<2>, c<3> to project through the side of the casing at the point of entry of the leads, and is retained in position by internal ridges or indentations s of the casing v. The self-adjusting contact h is loosely mounted between insulating washers i, i<1> on a reduced part of the spindle k. Alternatively, the washers i, i<1> may be of metal, Fig. 6, the stationary insulated contact consisting of a dished metal plate e<3> secured to the screw d. Fig 5 shows a modification, in which three stationary contact screws e, e<1>, e<2> are employed, one of which may be connected to earth.