GB612486A - Improvements in shielded electric sockets - Google Patents

Abstract

612,486. Two-part couplings. CRABTREE & CO., Ltd., J. A., CRABTREE, J. A., and MORGAN, R. W. May 25, 1946, No. 15925. [Class 38 (i)] The contacts of a socket outlet are screened by a shutter or shutters which are unlocked on inserting the earth pin and moved open on inserting the " live " pins of a corresponding three-pin plug. Two Z-shaped shutters a2, of insulating material, having opposed inclined surfaces b<2> at one end and inclined surfaces d<2> at the other, are located in recesses r in the cover of the socket, and are normally biassed to a locked position (shown in slotted lines) by a spring n which is centrally looped over a peg n<1> and the ends of which engage holes m in the shutters. Impingement of an earth pin c<2> on the inclined surfaces b<2> tilts the shutters outwards about their lower corners o to a position (shown in full lines) where they are clear of a fixed locking member p ; and may then be raised to their open position (shown in chain dotted lines) by the action of the " live " pins on the lower inclined faces d<2>. In a modification, two helical springs are used instead of the single looped spring. In a further embodiment, Fig: 5, the earth pin impinges on the inclined face of a lug v, thereby tilting the one-piece shutter clear of the locking member y and allowing the shutter to be raised by the " live " pins acting on the inclined faces d3. The Provisional Specification also refers to shutters with slots which co-operate with the locking members when the shutters are unlocked.