GB381977A - Improvements relating to electric switchgear - Google Patents

Abstract

381,977. Switchgear structures. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, and REGIS, E., 43, Tanfield Avenue, Cricklewood, both in London. July 21, 1931, No. 20831. [Class 38 (v).] In duplicate bus-bar, draw-out switchgear, a lamp or electricallyactuated flap exposing a legend is used to indicate which bus-bars are in commission when the movable part of the gear is in operative position. An arm 10 is pivoted about a pin 11 on or near to the fixed part of the gear and carries a two-way tumbler switch 16 by means of an arm 18, in which slides an actuating member 15 for the switch 16. A lever 12 is pivoted at the end of the arm 10 and carries a projection 13 connected with the slider 15. In action, as the movable part is being moved into engagement with the fixed part, a plugging member for engaging one of the bus-bars engages the lever 12 and rotates it anticlockwise, thereby throwing the switch dolly over and preparing the indicating circuit. The circuit is actually made when the movable part engages the arm 10 and rotates it about the pivot 11, thereby operating a further switch. The lever 12 is held deflected by means of a latch 20 on the arm 10 being moved by the movable part against the bias of a spring 21 into the dotted position in which it obstructs a projection 14 on the lever 12. The parts are self-restoring when the movable part is withdrawn. When the plugging member does not engage the lever 12, the switch 16 remains in the position shown, thereby preparing an indicating circuit for the other bus-bars. If a device such as shown is used on each phase the circuits are interconnected so as to show the operator also that the plugs are all properly inserted.