Patent ID: 7420446
Filing Date: 2008-09-02
Classification: H01H

Abstract:
1. A circuit breaker characterized by comprising a pair of stationary contactors which are disposed in opposition to each other and each of which is provided with a stationary contact, a movable contactor which includes a pair of movable contacts respectively disposed in opposition to the stationary contacts and which is capable of bridging both said stationary contactors, a switching mechanism section which operates when an overcurrent has flowed through said stationary contactors, a crossbar which is engaged with a substantially central part of said movable contactor from a side of said stationary contactors and which separates said movable contactor from said stationary contactors upon the operation of said switching mechanism section, a contact pressure spring which is engaged with said crossbar at one end and with the substantially central part of said movable contactor at the other end and which urges said movable contactor toward said stationary contactors, and arc extinction chambers which are respectively disposed near both end parts of said movable contactor and which extinguish an arc struck at the separation of said movable contactor from said stationary contactors, and further characterized in that said crossbar is formed with an inclined groove which extends obliquely downwards from a side surface thereof, and that a pin is snugly inserted into said inclined groove so as to be used as an engagement portion for one end of said contact pressure spring.