Patent ID: 9159985
Filing Date: 2015-10-13
Classification: H01H,H01M,Y02E

Abstract:
1. A circuit breaker comprising: an exterior case that includes an electrically-insulating case of plastic, and an exterior metal plate; a fixed contact metal plate that includes a fixed contact fixed to the electrically-insulating case of the exterior case; a moving contact metal plate that is fixed to the electrically-insulating case, and includes a moving contact arranged at the position opposed to the fixed contact; a bimetal that switches the moving contact metal plate from ON to OFF; and a heater that heats the bimetal, wherein the exterior metal plate and the fixed contact metal plate are arranged at positions opposed to each other and are fixed to the electrically-insulating case, wherein the heater, the bimetal and the moving contact metal plate are arranged between the fixed contact metal plate and the exterior metal plate in this order from a side of the fixed contact metal plate, the bimetal has a convex shape a center of which protrudes, and is arranged between the heater and the moving contact metal plate with the central protruding portion protruding toward the moving contact metal plate with the moving contact being in contact with the fixed contact, the electrically-insulating case includes a first wall and a second outer wall that protrude from both ends of the electrically-insulating case, and an accommodation space portion is formed between a first wall and a second outer wall, and accommodates the heater, the bimetal and a moving part of the moving contact metal plate, wherein the fixed contact metal plate is fixed to the first wall, and a stationary part of the moving contact metal plate is fixed to the second outer wall, the exterior metal plate is fixed to the electrically-insulating case, and closes an opening of the accommodation space portion, and the accommodation space portion of the electrically-insulating case is closed with the exterior metal plate being exposed on an exterior surface side, and the fixed contact metal plate comprises: an end part being embedded in a bottom of the accommodation space portion; a central part being embedded in the first wall of the electrically-insulating case; and a stepped portion being arranged for causing a difference in level between the end part and the central part so that the central part is higher than the end part, the stepped portion being embedded in a bottom of the electrically-insulating case, and wherein, at a first outer surface of the circuit breaker, the fixed contact metal plate is arranged at a same grade level as the electrically-insulating case, and the end part of the fixed contact metal plate is exposed outward to serve as a first exposed terminal at the first outer surface of the circuit breaker.