CIRCUIT BREAKER.

摘要

A circuit breaker equipped with a mechanism for current limiting by the use of electromagnetic repulsion, aiming at solving a technical problem of improving current-limiting performance by increasing the contact-opening speed of a contact plate of a current-limiting type circuit breaker and realizing the device in a compact size. The current-limiting contact plate is rotatably supported at its central portion, with one end thereof facing a movable contact plate, and with the other end facing a fixed conductor and electrically connected thereto. An electromagnetic repulsive force between the movable contact plate and the current-limiting contact plate and an electromagnetic repulsive force between the fixed conductor and the current-limiting contact plate are used as a couple of forces. It is therefore possible to increase the contact-opening speed and to decrease the distance between the current-limiting contact plate and the fixed conductor. The invention provides a circuit breaker which is small in size and is excellent in breaking performance.