GB430494A - Improvements in metal-clad electric switchgear - Google Patents

Abstract

430,494. Switchgear structures. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, and REGIS, E. D., 43, Tanfield Avenue, Cricklewood, both in London. Dec. 18, 1933, No. 35585. [Class 38 (v)] Bus-bar selection in multiple bus-bar, withdrawable switchgear is effected by providing on the fixed or movable part of the gear, sets of axially-slidable plugging contacts 18, (one set for each bus-bar set 4, 5), adapted, (when the two parts are in operative relation), to connect contacts on the movable part with contacts 6, 7 on the fixed part, and simultaneously moving two of the sets of contacts in reverse directions by a common operating means, such as handle 27 or a motor, accessible from the exterior of the casing without disturbing any part of the casing. The contact sets are preferably located in isolating chambers 15 on the movable part, and have screw-threaded extensions 20, insulated at 21 from the conducting parts, engaged by screwed sockets 25 which are coupled for simultaneous movement by gear wheels 26 and chain gearing. Sliding contacts 24 are connected by conductors 23 to the terminals 22 of the oil breaker, the operating- mechanism of which is shown at 16 and the racking-out motor at 17. 11 is a currenttransformer chamber. For single-phase gear, a single contact 18 constitutes a set, but for the three-phase gear shown, each set comprises three contacts. The Provisional Specification refers also to individual hand wheels for operating the plugging contacts.