CIRCUIT BREAKER

摘要

A circuit breaker, comprising a pair of fixed contactors (2) and (3) having fixed contacts (2a) and (3a), a movable contactor (4) having a pair of movable contacts (4a) and capable of bridging these both fixed contacts to each other, an opening/closing mechanism part (10) operating when an over-current flows in the fixed contactors, a crossbar (5) separating the movable contactor from the fixed contactors when the opening/closing mechanism part is operated, a contact pressure spring (7) having one end engaged with the crossbar and the other end engaged with the generally center part of the movable contactor and energizing the movable contactor in the direction of the fixed contactors, and arc-extinguishing chambers (8) installed near both end parts of the movable contactor and extinguishing arcs generated when the movable contactor is separated from the fixed contactors.