GB514163A - Improvements in and relating to snap-action electric switches - Google Patents

Abstract

514,163. Snap-action switches. PYE, Ltd., and BUTLER, C. E. M. March 30, 1938, No. 9731. [Class 38 (v)] Switch mechanism is contained in an insulating moulded box 10 fitted with a cover 25 through which passes a press button 24 an insulating tip 26 of which rests on a bent spring strip 16 fixed to the base of the box by a screw terminal 17. One end of a member 15 of spring metal such as beryllium bronze is carried by a small pip thereon which passes through a hole in the member 16, and the other end engages a V groove 13a in a metal strip 13 adjustable by a grub screw 14 to vary the compression of the member 15. Upon depression of the push button 24 the strip 15 is compressed longitudinally but cannot move downwards as a contact 22 which it carries at its mid position is in engagement with a fixed contact 18. It therefore bends so that the contact 22 moves up with a snap action into engagement with one or two contacts 20. The switch is hermetically sealed by cement round the openings as at 27, and a diaphragm 28 of material such as oiled cotton fabric which is secured across the top of the recess in the body 10.