Arc-control device of breaker

Abstract

The invention discloses an arc-control device of a breaker, which comprises a piston rod, a piston, an air cylinder, a static contact, a moving contact and a nozzle, wherein the air cylinder is isolated by the piston to form a hot air chamber and a cold air chamber, the piston is sleeved at the periphery of the piston rod and is positioned between a first limiting surface and a second limiting surface of the piston rod, and the nozzle is provided with a first air channel and a second air channel which are respectively communicated with the hot air chamber and the cold air chamber. According to the invention, hot airflow of arc heating can enter the hot air chamber, and in arc blowout, the cold airflow in the cold chamber can blow away conductive particles, so that the phenomenon that in the traditional structure, the cutting-off is not successful due to heat breakdown and air bubbles of the airflow can be avoided; the mode of forming the pressure by pressure air of the piston and the mode of forming the pressure by arc heating expansion are integrated, so that the size of the arc-control device is reduced; through the limiting surfaces of the piston rod, the drive mode of the piston can automatically adapt to the magnitude of current; and the expansion pressure generated by arc drives the direction of the movement of the piston to be constant with the direction of the movement of the piston rod, so that the work of the breaker can be reduced.

Description

technical field [0001] The invention belongs to the field of high-voltage switches, in particular to an arc extinguishing device for a circuit breaker. Background technique [0002] At present, circuit breakers mainly adopt self-energy or arc extinguishing devices combining compressed air and self-energy, and most of the existing arc extinguishing devices use a single expansion chamber 101, such as figure 1 shown. When the current is broken, the energy of the arc current generates heat, which increases the air pressure in the expansion chamber 101. When the current crosses zero, the arc energy disappears for a short time, and the hot gas in the expansion chamber is ejected out of the nozzle 19, and is taken away to form an arc. Conductive particles, so as to achieve current breaking. Although the hot air flow can be used to blow away the conductive particles to achieve breaking, because the hot air flow is not conducive to the reduction of the temperature of the arc area, ...

AI Technical Summary

Problems solved by technology

Furthermore, the existing arc extinguishing device uses a single expansion chamber. Since the arc process is extremely short (about 20 milliseconds), it is difficult to mix the hot and cold gases in the expansion chamber evenly in such a short time, so that the conductive particles are blown away. In the air flow, because of the uneven mixing of hot and cold gases, it is easy to form bubbles, which is not conducive to the interruption of the arc

[0003] On the other hand, no matter what kind of electric current is broken in the existing structure, the compressed air cylinder 100 is compressed, such as figure 1 As shown, but the actual situation is that when breaking a small current, compressed gas is needed to build up the pressure in the expansion chamber, while breaking a large current is mainly to use the arc's own ability to build up pressure in the expansion chamber (no compressed gas or only less Therefore, the compressed air of the existing arc extinguishing device combined with self-energy cannot adapt to the size of the breaking current and make corresponding adjustments, that is, the arc extinguishing device may be compressed when the compressed air is not needed, thus causing waste of work

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