GB289474A - Improvements in or relating to circuit interrupters - Google Patents

Abstract

289,474. Associated Electrical Industries, Ltd., (formerly Metropolitan-Vickers Electrical Co., Ltd.), (Assignees of Slepian, J.). April 29, 1927, [Convention date]. Arc-rupturing devices. - The arc formed between contacts 2, 4 of a contactor or other switch is driven into a deionizing structure comprising a series of metallic plates 24 having tapering V-shaped notches as shown in Fig. 5. The notches are aligned so that together they constitute a V- shaped groove into which the arc is driven, and the arc, in the case of an alternating-current is extinguished as the current passes through zero. If the arc persists after reaching the top of the V groove, it becomes split up into a series of short arcs between the plates 24, which are sufficiently long to prevent the arc reaching the top of them before the current reaches zero. The arc is driven upwards by a magnetic field formed between the sides of a U-shaped iron member 27, which field may be produced by the current flowing round the curved arcing horns 30, 31 which constitute the end portions of the contacts 2, 4. Electromagnetic switches. - The invention is shown applied to a contactor switch having three pairs of contacts 2, 4. Each movable contact 4 is supported in a slot at the end of the arm 5 and is adapted to be pressed into engagement with its fixed contact 2 by a spring 11 on a rod 10 passing loosely through holes in the members 4, 5. The three arms 5 are mounted on a bar 6, turnable on trunnions 7 and carrying an armature 17 attracted by the core 18 of an electromagnet 19. The weight of the armature 17 turns the bar 6 into open position when the magnet is de-energized. Specification 288,326 is referred to.