CIRCUIT BREAKER

摘要

A circuit breaker is provided to widen a minute gap in a rear part region of an opening end side by protruding a front end of the corresponding contactor from an opposite wall plane at an opening position of the movable contactor. A circuit breaker includes a fixed contactor(2), a movable contactor(3), and a couple of minute arc plates(9). A fixed contact pint(2a) and a movable contact point(3a) are inserted into the circuit breaker. The couple of minute arc plate(9) are arranged on both sides of the circuit breaker according to a moving path of the movable contactor(3) which is coupled with the fixed contactor(2). A minute arc space is formed on an opposite wall plane of the minute arc plates(9). The minute arc plates(9) protrudes a front end of the corresponding contactor from an opposite wall plane at an opening position of the movable contactor(3). The minute arc plate(9) separates the moving path of the movable contactor(3) into a front part region close to a closing position and a rear part region close to an opening position. A minute gap of the minute arc plate(9) is narrower at the front part region and wider at the rear part region.