To exhibit a high current-limiting breaking performance by preventing a second movable contactor, which has repulsively moved to an open-circuit position in the course of current breaking operation, from returning to a closed circuit position.
The circuit breaker unit includes a first movable contactor 3 that is connected to a switching mechanism and a second movable contactor 4 that is opposed to the first movable contactor 3 and biased by a contact spring 8 to a closed circuit position. The first and the second movable contactors 3, 4 are opposed to vertically, with the contacts 3a, 4a provided at the tip facing each other, with flexible lead wires 6, 7 connected to the rear end of the movable contactors, each movable contactor is pivotally supported turnably at the surrounding of pivots 3b, 4b. A magnetic shield plate 9 is interposed at the middle position of the rear end of the first movable contact 3 and the rear end of the second movable contact 4, and this suppresses generation of an electromagnetic repulsion force to bias the contactors in the closed circuit direction by acting on the rear end of each movable contact.
TOYAMA KENTARO
ISOZAKI MASARU
SATO AKIFUMI
| JPH03269929A | 1991-12-02 | |||
| JP2007207720A | 2007-08-16 | |||
| JPH08227648A | 1996-09-03 |
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