CIRCUIT BREAKER

摘要

A circuit breaker is obtained in which it is not required to dispose a phase block between interrupting units, and a case constituting an interrupting unit is hardly broken by flowing of a blast of arc gas which is produced between contacts when a large current such as a short-circuit current flows. In a circuit breaker having: a contactor mechanism which is configured by a movable contactor 18 and a stationary contactor 17; an opening/closing mechanism 30 for causing the contactor mechanism to perform an opening/closing operation; an arc distinguishing device 59 which attracts an arc in a predetermined direction, the arc being generated when the contactor mechanism is opened; and a housing 10 which is formed so as to accommodate the mechanisms and the device, the contactor mechanism and the arc distinguishing device are accommodated in cases 51 and 52 made of an insulating material to constitute a single-pole interrupting unit 50, 53, or 56, and a plurality of such single-pole interrupting units are closely juxtaposed to constitute a plural-pole interrupting unit. <IMAGE>