a circuit breaker

Abstract

The invention relates to the technical field of a circuit breaker, specifically to a small-sized circuit breaker. The circuit breaker comprises a contact assembly which comprises a movable contact (6) and a static contact (7), a driving mechanism (2) used for driving the movable contact (6) and the static contact (7) to switch on or switch off, an arc extinguishing apparatus (3) arranged on one side of the contact assembly, and a locking structure which is arranged at one end, equipped with a movable contact point, of the movable contact (6) or the arc extinguishing apparatus (3), wherein the locking structure performs locking of the movable contact (6) and the arc extinguishing apparatus (3) when the movable contact (6) moves to a position which is farthest from the static contact (7) in a switch-off direction, and performs unlocking when the driving mechanism (2) applies switch-on force to the movable contact (6). By virtue of the small-sized circuit breaker provided by the invention, electric arc re-ignition caused by the fact that the movable contact rebounds or even moves to a distance of electric arc breakdown when the movable contact is separated from the static contact and is in collision and contact with an arc striking plate can be avoided effectively.

Description

technical field [0001] The invention relates to the technical field of circuit breakers, in particular to a miniaturized circuit breaker. Background technique [0002] A circuit breaker refers to a switching device that can close, carry and break current under normal circuit conditions, and can close, carry and break current under abnormal circuit conditions within a specified time. A circuit breaker is generally composed of a contact system, an arc extinguishing system, an operating mechanism, a release, and a casing. The function of the circuit breaker is to cut off and connect the load circuit, as well as cut off the fault circuit, prevent the accident from expanding, and ensure safe operation. During the breaking action of the dynamic and static contacts of the circuit breaker with a load or a large fault current, the voltage between the dynamic and static contacts will cause the air dielectric discharge to form an arc. [0003] In order to ensure the reliable operatio...

AI Technical Summary

Problems solved by technology

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problem in the prior art that after the moving contact and the static contact are separated, the moving contact rebounds and moves to the arc due to the collision and contact between the moving contact and the arc strike plate. The distance that can be broken down causes the defect of arc re-ignition, thus providing a method that can effectively prevent the moving contact and the static contact from colliding with the arc plate, causing the moving contact to rebound or even move to the point where the arc can be broken down The distance, so that the miniaturized circuit breaker of the arc restrike

Images