Vacuum circuit breaker, vacuum circuit breaker contact slow closing method, and contact erosion measuring method and contact gap length setting method using that slow closing method

摘要

An adjusting bolt is screwed into a nut attached to a dolly, and is disposed such that a central axis thereof is parallel to a closing and opening direction of a contact. A lever is attached to a shaft. An electrically-insulating rod is coupled to a first end of the lever, and a pin is mounted to a second end of the lever. The adjusting bolt is turned and lowered to lower the pin. The lever and the shaft are pivoted by the lowering of the pin, and the electrically-insulating rod is raised. Thus, a movable contact moves toward a fixed contact, moving the contact from an open state to a closed state.