| 摘要 |
PROBLEM TO BE SOLVED: To provide a molded case circuit breaker which is capable of solving problems of positional errors of a moving contact and contact failures between points of contact by increasing the force for returning the moving contact to a home position.SOLUTION: A molded case circuit breaker according to the present invention includes fixed contacts 10 and a moving contact assembly A'. The moving contact assembly A' includes: a shaft 20; a moving contact 130 that is housed in the shaft 20; and springs 50 that apply torque to the moving contact 130. The shaft 20 includes: stopping faces 24a that are formed in a direction opposing the rotation of the moving contact 130; and guiding faces 24b that are folded from the stopping faces 24a. The moving contact 130 includes: first surfaces 34a that extend in a direction of the radius of rotation of the moving contact 130; and sliding surfaces 132a that are tilted to the first surfaces 34a and formed of a flat surface tilted toward the center of torque with respect to the line of action of a force F' in a tangential direction of a circumference of torque at the points in contact with the guiding faces 24b. |
