Protection assembly of movable static contact of plastic shell breaker

Abstract

The invention discloses a protection assembly of a movable static contact of a plastic shell breaker, comprising a static contact plastic piece and a plastic support piece, wherein the static contact plastic piece wraps the static contact, part of the static contact plastic piece and part of the static contact are arranged in a cavity of the plastic support piece, the static contact plastic piece is formed by combining a first plastic sheet with a second plastic sheet; a second round hole coaxial with a first through hole in the static contact is formed in the front side wall of the first plastic sheet; the front side wall on the lower part of the second round hole extends towards the bottom to form a first extension angle, the left side surface of the first extension angle is a first arc side surface always in clearance fit with the left side surface of the cavity, the rear side wall of the second plastic sheet extends towards the bottom to form a second extension angle, and the left side surface of the second extension angle is a second arc side surface always in clearance fit with the left side surface of the cavity. The lower part of the static contact is omni-directionally blocked, and the electric arc or metal particles generated by contact burnt by arc is prevented from spraying towards the lower part of the static contact, so as to ensure the normal reset of the static contact.

Description

technical field [0001] The invention relates to a molded case circuit breaker, in particular to a protection assembly for movable and static contacts of the molded case circuit breaker, and belongs to the technical field of low-voltage circuit breakers. Background technique [0002] In the contact arc extinguishing system of molded case low voltage circuit breaker, the static contact is the key part inside. The existing static contact structures of molded case circuit breakers are divided into two types: fixed static contacts and movable static contacts. In the structure of the movable and static contacts, the separation speed of the movable and static contacts is fast, the length of the arc is extended, and the breaking capacity is improved. The movable and static contacts are generally supported by plastic parts, and the plastic parts play an important role in protecting and supporting the entire movable and static contact structure. A common problem at present is that t...

AI Technical Summary

Problems solved by technology

The current common problem is that the plastic support of the static contact does not protect the static contact

But the defect of this structure is: although the fan-shaped boss at the rear of the plastic part can well block the space above, left and right, and behind the static contact, since the part is an integral part, the installation process will inevitably make the bottom of the static contact The position is not blocked, which will cause the metal particles generated during the breaking process of the switch to attach or even accumulate in the area under the static contact, resulting in welding or arcing between the static contact and the electrical connection, reducing the electrical gap Easy to break down and affect the switch performance

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