Moving contact system for frame circuit breaker

Abstract

The invention relates to a moving contact system for a frame circuit breaker, and the system comprises an upper bottom plate, a lower bottom plate, a static contact, a moving contact, and an operating mechanism. The upper and lower bottom plates are fixed on the circuit breaker body, and are used for supporting and limiting the moving contact and the static contact. The moving contact comprises a moving conducting bar, a mating part, a rotating shaft, a moving contact body, a moving arc-striking piece, a connecting part, a split contact, and a plastic case rack. The moving arc-striking piece is fixed on the upper bottom plate. One end of the connecting part is fixed on the moving conducting bar, and the other end of the connecting part is connected with the right end of the moving arc-striking piece. Compared with the prior art, the system enables the moving arc-striking piece to be directly connected with the moving contact, and greatly increases the transfer speed of an arc from the split contact of the moving contact to the moving arc-striking piece, thereby reducing the burning time of arc on the split contact, speeding up the process that the arc enters an arc extinguishing chamber, and improving the switching performances of a circuit breaker.

Description

technical field [0001] The invention relates to the technical field of circuit breakers, in particular to a moving contact system of a frame circuit breaker. Background technique [0002] With the rapid development of the national economy, the capacity of the power grid will continue to rise, so improving the breaking capacity of circuit breakers is an eternal goal. When the existing circuit breaker breaks the short-circuit current, the breaking capacity of the circuit breaker is often limited due to the severe contact ablation of the moving contact and the inability of the arc to enter the grid of the arc extinguishing chamber in time. As we all know, when the short-circuit current is broken, when the moving and static contacts of the circuit breaker are separated, an arc will be generated between the moving and static contacts. The longer the arc stays on the moving and static contacts, the more The more serious the ablation. Therefore, it is the goal pursued by the indu...

AI Technical Summary

Problems solved by technology

[0003] As known in the industry, in the existing circuit breaker, the static arc is connected to the static contact. Under the action of electromagnetic force and airflow thrust, the arc can quickly enter the static arc from the static contact, thereby reducing the Ablation of the static contact; since the moving contact is a moving part, there has been no good plan to set the moving arc leading piece connected or in contact with the moving contact. In the known contact structure, the moving leading arc piece is arranged on In the arc extinguishing chamber, there is a certain gap between the moving arc plate and the split contact of the moving contact, which is about 5mm. The transfer of the arc from the moving contact to the moving arc plate needs to break down the air gap to complete the transfer. , and this process often takes a long time and may be repeated, so that the ablation time of the arc on the split contact of the moving contact is too long, and the burning of the moving contact is serious, which greatly affects the breaking ability and opening of the circuit breaker. Number of breaks

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