| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a circuit breaker in which a tripping time of appropriate range can be ensured when an overcurrent flows even if a thermal tripping mechanism using a bimetal is employed. <P>SOLUTION: In the circuit breaker, an external connection terminal 13 is connected with a bimetal 20 which bends by generating heat with a current flowing between a fixed contact and a movable contact 11, supported at the proximal end and has a free distal end, or one connection conductor 14 to be connected with the movable contact 11 is connected with the free end, and the other connection conductor to be connected with the external connection terminal 13 or the movable contact 11 is connected with the support part. The connection conductor 14 connected with the free end of the bimetal 20 is formed so that the amount of heat transfer by thermal conduction is smaller than that of the connection conductor connected with the support of the bimetal 20. A heating part which generates heat by electrification more on the free end side of intermediate position than the support of the bimetal 20 is provided. <P>COPYRIGHT: (C)2012,JPO&INPIT |
