Contactor falling-resistant device

Abstract

The invention belongs to low voltage electrical equipment, relating to a contactor falling-resistant device in a low-voltage circuit breaker. The contactor falling-resistant device comprises a spindle body and a moving contact, wherein the moving contact penetrates through the inner cavity of the spindle body from front to back and can rotate around the center of the spindle body; the moving contact is in central symmetry, the front and rear ends of the moving contact are respectively provided with a moving contact point which corresponds to fixed contact points at the upper and lower parts of the circuit breaker; the front and rear part of the centre of symmetry of the moving contact are respectively provided with a chute; each chute is internally provided with a bayonet lock which stretches out of the two sides; two ends of each bayonet lock are dragged by a pair of tension springs positioned outside the spindle body; the fixing ends of the tension springs are connected to fixing pins at two external sides of the spindle body; the upper and lower edges of the spindle body are respectively provided with a section of camming surface which is composed of two hollow sections at two ends and a hunch-up section in the middle; and the bayonet lock is always pressed on the camming surfaces under the action of the tension springs and can stay at the bottoms of the two hollow sections. The invention has simple structure and reliable action and is convenient to manufacture and install.

Description

technical field [0001] The invention belongs to low-voltage electrical equipment, and relates to a contact drop prevention device in a low-voltage circuit breaker. Background technique [0002] The rotating shaft part of a low-voltage circuit breaker usually includes a rotating shaft body driven by a circuit breaker operating mechanism and a movable contact installed on the rotating shaft body. During normal operation, the rotating shaft drives the moving contact to rotate to realize the opening and closing of the static contact of the circuit breaker. However, when the circuit breaker is over-current due to a fault such as a short circuit, the contact needs to be disconnected quickly, and the use of It takes a long time for the protection circuit of the operating mechanism to drive the rotating shaft to perform the opening action. Therefore, in order to ensure that the contacts can be disconnected quickly during overcurrent, the rotating shaft parts of the existing structu...

AI Technical Summary

Problems solved by technology

The existing new contact drop prevention device (such as US patent document US005313180A and Chinese patent 200610037996.9, etc.) is usually provided with a cam surface on the edge of the movable contact, and the positioning of the spring and the bayonet on the cam surface is used to realize the repulsion of the movable contact. Most of these structures have defects such as complex structure, high manufacturing difficulty, high manufacturing and installation precision requirements, and poor operational reliability.

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