GB436122A - Improvements in or relating to electrical circuit interrupters - Google Patents

Abstract

436,122. High-tension switches; heavy-current switches. WESTINGHOUSE ELECTRIC & MANUFACTURING CO., East Pittsburg, U.S.A.-(Assignees of Slepian, J. ; 1115, Lancaster Street, Pittsburg, U.S.A.) Feb. 18, 1935, No. 5237. Convention date, March 16, 1934. [Class 38 (v)] Circuit-breakers have contacts 25, 27 arranged between oppositelydisposed plate members 1 the walls of which define a narrow passage 9 in which the arc is moved laterally, and a substantial portion of the surface of at least one of the members is lined with a solid material capable of evolving large quantities or arc-extinguishing gas when placed in proximity to an arc. Suitable material is an organic material such as fibre, or boric acid, which evolve hydrogen and water vapour, respectively. As shown, tile-like members 23 of compressed boric acid are fixed as by cementing to the inner surfaces of the insulating plates 1, which are spaced by insulating members 3, 5, 7 so as to form the passage 9 open only at the top. The structure is secured together by bolts 13, reinforced by pressure-resisting bolts 17 with insulating sleeves 19, and a further insulated bolt 35 secures the fixed contact 27. Both contacts have arcing horns 29 and a pair of flat iron members 39 are embedded in the lining of each plate 1, those associated with the contact 25 being located adjacent the open position thereof, so as to facilitate the movement of the arc to the top of the passage 9. Both contacts are only slightly less wide than the passage 9, and the space between them and members 3, 7 is occupied by insulating members 41 so as to prevent gas being trapped there. Bolted at 15 to plates 1 is a flame suppressor 11 comprising a metal box 43, on bolts 49 in which rest three baffle units comprising side members 47 to which the baffles 45 are fixed, as by riveting. Vents 51 are formed by punching out sections 53 of the closure member.