GB934949A - Explosion-proof electrical dead front receptacle - Google Patents

Abstract

934,949. Two-part couplings. HARVEY HUBBELL Inc. July 11, 1961 [Feb. 13, 1961], No. 25139/61. Class 38 (1). [Also in Group XXXVII] A socket 1 for use in explosive gas or vapour atmospheres has laterally arcuate contacts 19 connected to supply conductors 32, 33 through microswitches 30, 31 enclosed in a sealed chamber at the rear of the insulating body 12 of the socket. Actuating spring arms 103 of the microswitches are operated by a rotatable cam 99 mounted on a shaft 97 which passes through the body 12 into an outer chamber 17 formed by an insulating cylindrical projection 11 attached to the body 12. When a co-operating plug 66 having stud contacts 73 and a stud earthing contact 74 is inserted into the chamber 17 through a suitably shaped aperture (Fig. 8, not shown), it pushes a spring-loaded sliding insulating closure 92 back allowing a keyway 111 (Fig. 9, not shown) in the plug 66 to engage a key 110 in the end of the shaft 97. In this position the contacts 19 in the socket are engaged with the contacts 73, 74 and a turning movement of the plug 66 is transmitted by the key 110 and keyway 111 through the shaft 97 to the cam which then operates the actuating arms 103 of the microswitches 30, 31 which then complete the connection between the supply conductors 32, 33 and the contacts 19. The plug is held in engagement in the socket by the action of the spring-loaded closure 92, on the end of the plug causing the contacts 73, 74 to abut shoulders 113 (Fig. 8, not shown), formed by the shape of the entry aperture in the end of the projection 11. Specification 837,189 is referred to.