GB772781A - Improvements in or relating to electric tumbler switches - Google Patents

Abstract

772,781. Tubular switches. WARD & GOLDSTONE, Ltd., and COUYOUMDJIAN, A. O. May 27, 1953 [May 27, 1952], No. 13363/52. Class 38(5) A dolly-operated switch in which the inner end of the dolly is spring-urged to impart a snap-action is characterized by a movable bridging contact directly supported in or on the dolly with freedom to float in relation thereto. The switch; Figs. 1, 2, comprises a dolly 16 whose trunnions 20 are held against seatings 21 in the underside of a moulding 15 by a spring- steel strip (or two superimposed strips) 12 supported on a base 10 and engaging the V-shaped dolly end 22. A recess 25 formed in the underside of the moulding 15 accommodates fixed contacts 26 and a bridging contact rod or tube 24 supported within a clearance hole 23 in the dolly so that in the "on" position shown the contact 24 aligns itself with the fixed contacts. A two-way switch may be formed by providing a further pair of fixed contacts on the moulding 15 on the other side of the dolly pivot axis. The base 10 may be extended to form a switch-socket and the socket contacts may be constructed as disclosed in Specifications 714,889 and 772,782 [both in Group XXXVI]. In a modification (not shown) the moulding 15 and base 10 are integral and the contact 24 is situated between the dolly finger. piece 19 and the pivot 20. In the construction, Figs. 4, 6, a projection 35 on one side of the dolly 16 is recessed at 36 to receive a bridging contact 37 rockable about a rib 39 and secured to the dolly by a circlip 40 which engages a groove 38 in the contact and embraces the projection 35. The fixed contacts comprise strips 41, 42 fixed to the underside of a flush-plate 15. In 'another modification (Fig. 7, not shown) the moving contact comprises a flat strip projecting from both sides of the dolly and floatingly mounted in a diamond-shaped opening in the dolly. Specification 772,783 also is referred to.