Breaker arc-control device

Abstract

The present invention relates to a breaker arc-control device. The device comprises an arc-control chamber, a curve runway and an arc-control grid plate set located in the arc-control chamber. The arc-control grid plate set comprises a plurality of arc-control grid plates; the curve runway is located between a U-shaped first end tab and an arc-shaped second end tab, one end of the first end tab is extended to the arc-control grid plate set, and the other end of the first end tab is extended to the fixed contact of a breaker; one end of the second end tab is extended to the arc-control grid plate set, and the other end of the second end tab is extended to the moving contact of the breaker and corresponds to the portion of the movement locus of the moving contact of the breaker; and an arc-control grid plate located at the middle of the arc-control grid plate set is extended facing the direction of the curve runway to form a palping foot, and the palping foot is configured to divide the curve runway close to the arc-control grid plate set into two parts consisting of a first curve runway and a second curve runway. The arc-control device can shorten the arc-control time and improve the survival ability of the breaker under a short-circuit heavy current.

Description

technical field [0001] The invention relates to an arc extinguishing device used on a circuit breaker, belonging to the technical field of circuit breakers. Background technique [0002] The arc extinguishing device of a miniature circuit breaker usually consists of an arc run connecting the moving and static contact pairs with the arc extinguishing chamber, an arc extinguishing grid set and an exhaust duct. Such as figure 1 As shown, usually the running arc track 5 is surrounded by a U-shaped first arc-leading plate 1 and an arc-shaped second arc-leading plate 2, and one end of the first arc-leading plate 1 extends to the arc-extinguishing grid group 3. The other end extends to the static contact 11 of the circuit breaker; one end of the second arc strike plate 2 extends to the arc extinguishing grid set 3, and the other end extends toward the moving contact 12 of the circuit breaker and is connected to the moving contact of the circuit breaker 12 corresponding to the par...

AI Technical Summary

Problems solved by technology

[0003] However, the existing arc extinguishing devices tend to easily produce the following two defects: 1. The arc cannot enter the arc extinguishing grid group 3 smoothly, and continues to burn at the bell mouth 21 at the end of the arc track until the first and second arc strike plates 1. 2 burns out completely, thereby destroying the circuit breaker; 2. After the arc enters the arc-extinguishing grid group 3, it continues to move to the end 22 of the grid group, resulting in back breakdown phenomenon, and the back breakdown causes the arc to continue to burn, and the short-circuit energy cannot is suppressed, the circuit breaker fails

These two situations are the main short-circuit failure modes of existing circuit breakers. The essence is that the short-circuit arc is not extinguished in time, and the arcing time is too long to exceed the limit of the circuit breaker, causing the circuit breaker to fail.

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