Patent Number: 6,310,528

Title: Overcurrent-tripping device for circuit breaker

Abstract: In an overcurrent-tripping device for a circuit breaker, an electromagnet is used to open a movable contact shoe when a heavy current flows through a conduction path. A push rod is provided so as to contact the movable contact shoe. The electromagnet of the overcurrent-tripping device is located above the push rod so as to attract a movable iron core of the overcurrent-tripping device linearly along a moving direction of the push rod. When the heavy current such as a short-circuit current flows through the conduction path, the movable iron core is attracted to push the movable contact shoe via the push rod for rapid opening of the movable contact shoe. Thus, before a tripping operation of the opening-and-closing mechanism, the movable contact shoe is moved, so that the time required by the movable contact shoe for the opening operation is reduced.

Inventors: Kuboyama; Katsunori (Saitama, JP), Uchida; Naoshi (Saitama, JP), Nagahiro; Isamu (Saitama, JP)

Assignee: Fuji Electric Co., Ltd.

International Classification: H01H 71/12 (20060101); H01H 71/24 (20060101); H01H 73/00 (20060101); H01H 73/04 (20060101); H01H 067/02 ()

Expiration Date: 10/30/2018