| 摘要 |
PROBLEM TO BE SOLVED: To provide a spring operation unit capable of improving the reliability by preventing a gear from being fixed when releasing energy of a closing spring.SOLUTION: An operation mechanism for a circuit breaker is configured by: a breaking spring for performing an open-circuit operation of a breaking part by releasing energy; a closing spring for performing a close-circuit operation of the breaking part by a cam rotating by storing energy; a large gear 1 having the same rotation axis as the cam and partially missing teeth; and a medium gear 2 engaged with the large gear 1 and rotated and driven by a drive force from a motor. An elastic body 22 for a synchronization claw is clipped to a toothless part 1a of the large gear 1, and one end of a synchronization claw 5 having a plurality of teeth engaged with the medium gear 2 is freely rotatably supported. The one end of the synchronization claw 5 is freely oscillatably supported by the toothless part 1a by means of an elliptical rotation shaft hole 5a having a longer axis substantially parallel to an axis in an expansion and contraction direction of the elastic body 22 for a synchronization claw. A restriction part 5d accepting a stopper 23 provided to the toothless part 1a to restrict the oscillation is provided to the other end of the synchronization claw 5. |
