GB864327A - Improvements in or relating to fluid pressure electric switches - Google Patents

Abstract

864,327. Fluid actuation of switches. W.H.R. DEVELOPMENTS Ltd. Aug. 7, 1957 [May 9, 1957], No. 14800/57. Class 38 (5). A pressure-operated switch has resilient distance-piece members interposed between a fixed abutment and a control-member supported to move in unison with a pressure deformable or displaceable member so as to maintain the connection between the control member and a member loaded for movement in one direction and adapted to make and break contacts. In Fig. 1 the diaphragm comprises a beryllium copper, stainless steel or latex disc 34 and a rubber impregnated fabric disc 42 urged by fluid pressure against a spring disc 44 and the stud 33. A spacer disc 43 has a larger hole than the disc 44 so as to allow the latter to deflect with the diaphragm. Three dished springs 37 are arranged in a concertina-like stack between an enlargement 39 on the stud arid the end of the bore 38 in the housing 31. The stud 33 carries a screw 57 which passes through two leaf-springs 54, 60 with its head holding them against their bias so that when the stud 33 is lifted by the diaphragm 34, 42, the springs 60, 54 successively operate micro-switches 58, 48 adjustably mounted on threaded studs 51. Stop screws 61, 62 are provided for the leafsprings. In Fig. 3 the leaf-springs are replaced by two levers (one shown at 68) co-pivoted at 69 and having lugs 67<SP>1</SP>, 68<SP>1</SP>, around the screw 57 separated by washers 76, 77. The levers are individually biased to the switch-operated position by springs 75 on pillars 72.