AN IMPROVEMENT IN OR RELATING TO IMPROVED CIORCUIT-BREAKERS WITH IMPROVED MAGNETIC ARC-DRIVING SYSTEMS

摘要

1474476 Arc extinguishing WESTING- HOUSE ELECTRIC CORP 12 Aug 1974 [21 Aug 1973] 35436/74 Heading H1N An arc extinguishing arrangement comprises a laminated magnetizable yoke 4 surrounding at least one of the contacts on a pair of parallel conductors 13, 14 on three sides so that an arc drawn between the contacts will be magnetically driven outwardly by the field "B" induced in the yoke by the current I flowing in the conductors. Arc extinguishing plates 29 of non- magnetizable material e.g. copper with tungsten tips, or ceramic, are provided at the exit end of the space encompassed by the yoke. Instead of being window shaped as shown the yoke may be U-shaped e.g. comprising only the portion above the line X-X in Fig. 9 (Figs. 26 and 27, not shown). Arcing horns may be provided (Fig. 3, not shown). The arc-extinguishing structure may be fabricated on a base plate for use with standard replaceable circuit breaker units (Figs. 10-17, not shown). An overload-release circuit-interrupter having two sets of contacts, with the arc-extinguishing arrangement of the invention provided for each set, release being effected by induction in a magnetic drive structure acting on a bridging contact arm against a magnetic holding device, is described (Figs. 22-25, not shown).