GB875258A - Electric fuse switch - Google Patents

Abstract

875,258. Snap-action switches. VERHULST, R. Nov. 26, 1957 [Jan. 22, 1957; April 15, 1957], No. 36788/57. Class 38 (5). A snap-action fuse-switch comprises a stationary insulating part 1 with a double set of spring clip contacts 3 in each pole, a sliding part 32 mounted on guide rods 38 and carrying contact knives 55 with respective interconnecting fuses 56, and an actuating mechanism with handle 12 to operate cranks 13, 14 and 15, 16 for closing and opening the switch by compressing springs inside sleeves 26. The rods 38 are secured to the moving part 32 and slide in bushings 35, 36 screwed into the base part 1 (Fig. 4). Each rod 38 has two grooves 39, 40 suitably spaced to co-operate with spring-loaded balls in the bushing 36 and lock the switch in its closed and open positions respectively. Rubber rings 43 and 48 act as shock-absorbers. Fig. 5 shows one crank (15, 16) and associated actuating mechanism in its condition just prior to closure of the switch. Connecting rod 22, slidable in a pivoted member 20, is compressing spring 28 against the end 29 of sleeve 26 which is anchored at its other end in the moving part 32 of the switch by means of a rubber insert 31. When the locking force of the balls acting on the rod 38 is overcome the switch suddenly closes. On reverse movement of the handle 12 the crank causes member 20 to slide along rod 22 and engage a tube 25 fitted loosely on the rod 22 but having a ring 27 which compresses spring 28, tending to cause opening of the switch, which occurs when the locking action of the balls on rod 38 is again overcome. In a modification (Figs. 12 and 13, not shown), the operating handle 12 is pivoted in the vicinity of the moving part 32 on a bracket extending from the side of the fixed part 1, and operates the cranks by means of a connecting rod.