Arc extinguishing chamber for high-voltage circuit breaker

Abstract

The invention provides an arc extinguishing chamber for a high-voltage circuit breaker. The arc extinguishing chamber comprises a motion reversing mechanism, a driving side contact and a driven side contact, wherein the driving side contact and the driven side contact are arranged on the motion reversing mechanism separately and move oppositely; the motion reversing mechanism comprises a driving side push-pull rod connected with the driving side contact, a driven side push-pull rod connected to the driven side contact, a reversing device and an integrally molded guide rail; two motion channelsfor opposite motion of the driving side push-pull rod and the driven side push-pull rod are arranged in the guide rail; the guide rail is provided with a driving side push-pull rod sliding rail and adriven side push-pull rod sliding rail; the driving side push-pull rod and the driven side push-pull rod are arranged in the corresponding sliding rails through shaft pins in a sliding manner; a limiter is arranged at one side of the driving side push-pull rod sliding rail and/or the driven side push-pull rod sliding rail for limiting and auxiliary guiding of the driving side push-pull rod and the driven side push-pull rod. A double-acting arc extinguishing principle is adopted by the arc extinguishing chamber, so that the arc extinguishing chamber is simple in structure, reasonable in design, simple in operation and reliable in working, the stability is greatly improved and the mechanical life is greatly prolonged.

Description

technical field [0001] The invention relates to the field of high-voltage switch manufacture and design, in particular to an arc extinguishing chamber for a high-voltage circuit breaker. Background technique [0002] Since the appearance of SF6 circuit breaker in 1956, relying on the excellent insulation performance of SF6 gas, SF6 gas insulated circuit breaker has rapidly occupied the medium and high voltage breaking field, becoming one of the most widely used high voltage circuit breaker types in the world. As the voltage level increases, the requirements for the operating mechanism of the circuit breaker continue to increase. Through the double-action principle, the contacts on both sides of the arc extinguishing chamber of the circuit breaker move in the opposite direction at the same time, which increases the relative movement speed between the contacts. In the case of completing the current breaking with the same capacity, further reducing the operating work required b...

AI Technical Summary

Problems solved by technology

For a double-action interrupter that uses a fixed shaft type transmission rod as a relative motion transmission device, two independent splints are usually used to form a guide rail through a stud fastening method, such as the "switching device" disclosed in Chinese patent CN104380418A. The rotating shaft transmission rod and the double-action opposite moving parts are fixed in it. Since the installation position of the double-action interrupter transmission device is located in the core part of the interrupter, a large amount of heat will be generated when breaking, and the components of the guide rail have different thermal expansion coefficients. , after a long time and many times of breaking operations, the guide rail fasteners are susceptible to loosening due to repeated drastic changes in temperature, which will have a fatal impact on the reliability of the circuit breaker; secondly, the double splint fastening method During the opening and closing operation of the moving structure, relying on the internal through groove formed by the processing of the splint to guide the push-pull rods on the driving side and the driven side, this puts forward high requirements on the machining accuracy and coordination of the clips that make up the guide rail. In addition, , when the double-action interrupter is applied to the horizontal circuit breaker structure, due to the effect of gravity, the two sides of the double-action interrupter produce a certain deflection respectively, so that when the contacts on both sides of the double-action interrupter open and close In the case of non-coaxial movement, after multiple opening and closing cycles of the arc extinguishing chamber, the reversing transmission structure of the double-acting arc extinguishing chamber is often caused by the non-coaxial movement of the push-pull rod and the related guide parts of the internal guide groove. The interference (such as the collision between the edge of the push-pull rod and the inner support column of the guide rail) appears stuck or even stuck, which greatly affects the reliability of the double-action interrupter; again, the fixed shaft transmission in the fastening method of the combined splint There is sliding friction between the rod and the guide rail wall when the rod rotates. The fixed parts (such as shaft pins) between the fixed shaft transmission rod and the guide rail are prone to wear after repeated breaking operations, which in turn causes the fixed shaft transmission rod and the guide rail to produce relative friction. Displacement, which affects the stability of the arc extinguishing chamber

[0004] In order to solve the influence of gravity deflection when the arc extinguishing chamber is used in horizontal circuit breakers, and to improve the non-coaxial movement of the contacts on both sides of the arc extinguishing chamber when they open and close, the patent "Circuit Breaker with Bonded Bushing Insulators" (US2004251237A1) proposes an insulating The supporting cylinder structure bridges the contacts on both sides of the arc extinguishing chamber through the insulating supporting cylinder, thereby reducing the impact of the deflection of the contacts on both sides of the arc extinguishing chamber due to gravity on the opening and closing of the arc extinguishing chamber through the guiding effect of the insulating support cylinder. Influence, the above patents to a certain extent improve the influence of gravity on the double-action interrupter used in the horizontal circuit breaker structure when opening and closing operations, the movement of the contacts on both sides is not the same axis, but compared with the fully open structure of the contacts on both sides, When the breaking time interval is short (such as T100s reclosing), a large amount of heat will accumulate inside the insulating cylinder and cannot be discharged in time, which will weaken the recovery speed of the medium between the fractures in the insulating cylinder. The accumulation of breaking and decomposing dust will also easily deteriorate the insulation performance of the arc extinguishing gas between the fractures during subsequent breaking, and affect the reliability of the subsequent breaking process. The structure of the arc extinguishing chamber has been reduced to a certain extent

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