GB936486A - Improvements in electrical fittings such as plugs - Google Patents

Abstract

936,486. Electrical plugs. K. Z. RUMBLE. May 26, 1960 [May 29, 1959 (3); June 10, 1959], No. 18680/60. Class 38 (1). A plug consists of a body 10 with an earth pin 30 and pairs of retractable contact pins 24, 26 spaced further apart the further they are from the earth pin, to provide, with the earth pin which is common to all of the pairs of contact pins, at least two triangulated sets of pins, each set being capable of engaging one of a standard range of three-member outlets. The pins can be flat or rounded, and the earth pin when of the rounded type is telescopic, composed of units of different diameters, but when of the flat type is of jack-knife construction (see Figs. 7 and 8, not shown). Each contact pin is housed in a metal socket 32 in a hole 34 retained in position by a cover-plate 36. Threads 38 in the socket engage with threads 40 on the distal end of the pin. A head 42 on the pin prevents complete withdrawal from the socket. Rotation of the pin either locks it in projected position or frees it for retraction into the socket 32. The plug body and coverplate are made of resilient material for use as a two-pin plug when the earth pin will be retracted, and the plug can be squeezed to give the correct pin spacing. Fig. 10 illustrates a plug having both rounded pins and flat pins 104, 106, 108. The pins may have rubber noses to avoid short-circuiting.