Enclosed switch with cover and connector interlock

1,087,878. Interlocking two-part couplings and switches. ARROW ELECTRIC SWITCHES Ltd. Oct. 16, 1964 [Oct. 17,1963], No. 55134/66. Divided out of 1,087,877. Heading H2E. Actuation of the operating handle 40 of a switch from the " off " to the " on " position moves a link 100 longitudinally to the position shown in which, by co-operation with a lug 131 on a plug 110, it prevents either insertion of the plug or its removal if already inserted. The plug, Fig. 3 (not shown), which has four radially extending contacts (115-118), one of which is enlarged for polarization purposes, co-operates with a socket 122, mounted in the box 10 housing the switch, in a bayonet fashion, and the lug 131 may be integral with the plug housing or carried by a detachable ring. The link 100 and a switch-operating bail 12 are actuated by the handle through a lost-motion mechanism, Fig. 6 (not shown), and are subject to an over-centre snap-action spring 30. A further interlock, Fig. 5 (not shown), is provided between the handle and a lid 49 of the box 10.