GB371340A - Improvements relating to oil circuit breakers - Google Patents

Abstract

371,340. Oil-break switches. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London.-(General Electric Co. ; Schenectady, New York, U.S.A.) Jan. 13, 1931, No. 1166. [Class 38 (v).] Arcs in series are drawn between the fixed contacts 5, 6 and the bridging contact-member 7 under oil and within a lower part of the casing separated from the part containing the actuating mechanism by an insulating partition 4 having a narrow slot through which the contactarm moves and a wider slot 13 opposite the contact 5. The oil pressure produced at the break 6, 7 remote from the slot 13 forces a stream of oil across the arc at the break 5, 7. In a modification, Fig. 4, applied to the usual rectilinearly-moving type of bridging contact member 40 co-operating with fixed main and arcing contacts 36, 43, a chamber 47 is formed within the oil pot with an opening 48 opposite the right-hand fixed contacts so that the pressure produced at the other contacts (which may break circuit first) produces a flow of oil across them through the opening and along the passage 49. Automatic circuit-breakers.-In the first instruction the switch is closed by the closing electromagnet 23 acting on the knee of the toggle 22, 26 and driving the contact-lever 8 through the overset and locked toggle 26, 21. It is tripped by a two-armed lever 30, 37 normally held by the electromagnetic latch 31 against the action of the spring 29 and when released upsetting the toggle 26, 21. As the switch lever moves to the open position, it depresses a lever 34 which resets and automatically relatches the tripping lever 30, 27. Specification 193,136, [Class 38 (v), Electric switches &c.], is referred to.