JPH0378925A - Gas load switch - Google Patents

Abstract

PURPOSE:To reduce the size and cost of a gas load switch by forming a closed gas chamber, in which an insertion hole at the tip of an insulating nozzle is only open, in the insulating nozzle and providing an insulator, which helps gas production in contact with arc, in the gas chamber. CONSTITUTION:A closed gas chamber 16 is formed in an insulating nozzle 13, in which an insertion hole 11 is only open, and an insulated cylinder 17 for gas production is provided in the gas chamber 16 in such a manner that it may be burried in between the insulating nozzle 13 and a moving arcing contact 7. When arc 15 arises in between a fixed arcing contact 4 and the moving arcing contact 7 during an open pole, the arc 15 is put in contact with the insulated cylinder 17 to allow gas evaporation from insulated cylinder 17. Such gas raises pressure in the gas chamber 16 and is discharged from the insertion hole 11 out to the insulating nozzle 13 which has low pressure, and at this time the arc 15 is extinguished. It is thus possible to eliminate a buffer room and a piston and reduce the size and cost of a gas load switch.

Description

[Detailed description of the invention] A. Industrial application field The present invention relates to a gas load switch with a simplified structure.

B1 Overview of the Invention The present invention provides a gas load switch that extinguishes an arc generated between a fixed arcing contact and a movable arcing contact when the contact is opened by spraying an insulating gas on the arc. By installing an insulator in the gas chamber that generates gas when it comes into contact with the arc, the gas generated from the insulator when it comes into contact with the arc accumulates in the gas chamber and is then blown onto the arc, extinguishing the arc. This is what I did.

C3 Conventional technology Switches include gas circuit breakers that cut off fault current, as well as gas load switches that switch normal loads.

A gas load switch has a structure having a buffer chamber like a gas circuit breaker. This is because gas load switches, unlike gas new line switches, have the same severe transient recovery voltage applied between the electrodes after current interruption as in gas circuit breakers, and require high insulation recovery characteristics due to the gas flow. be.

The structure of a conventional gas load switch is shown in Figure 4.

As shown in the figure, the gas load switch is composed of a fixed unit 1 and a movable unit 2. The fixed unit 1 is composed of a hollow fixed main contact 3 and a fixed arcing contact 4 provided at the center of the main contact.

On the other hand, the movable unit 2 has a movable arcing contact 7 at its tip, a hollow drive rod 8 that also serves as a buffer cylinder, and is driven in the left-right direction in the figure, and a drive rod 8 that covers the movable arcing contact 7.
An insulating nozzle 13 is fixed to the end face of the insulating nozzle 13 and has an insertion hole 11 at its tip and forms a discharge path 12 between it and the movable arcing contact 7, and a driving robed 8 is integrally molded on the outside of the insulating nozzle I3. a movable main contact 14,
A ring-shaped piston 10 is attached to a fixed part (not shown) via a hollow rod 6 and is slidably provided in a drive rod 8 as a suction/exhaust means for sucking in and discharging insulating gas into a buffer chamber 9. Consists of. Note that 5 is a sealing material. Each unit is provided in an insulating gas such as sFe gas, and constitutes a gas load switch.

In such a gas load switch, when the drive rod 8 is driven to the left in the figure and is closed, insulating gas is sucked into the buffer chamber 9 through the insertion hole 11, and the drive rod 8 is moved to the right in the figure. When the buffer chamber 9 is driven to shut off, the insulating gas in the buffer chamber 9 is discharged from the discharge path 12 as shown in FIG.

The insulating gas is blown onto the arc 15 generated between the fixed arcing contact 4 and the movable arcing contact 7 to extinguish it, and is then discharged through the insertion hole 11.

D0 Problems to be Solved by the Invention However, since the insulating gas must be compressed, a large driving force is required to drive the drive rod, and a piston is also required. In today's world where gas load switches are required to be smaller and lower in cost, there are limits to miniaturization and cost reduction with a configuration in which insulating gas is compressed and blown onto the arc.

Therefore, an object of the present invention is to provide a gas load switch that solves the above problem.

83 Means for Solving the Problems The structure of the present invention for achieving the above object is to fix a fixed arcing contact in an insulating gas, and provide a fixed main contact outside the fixed arcing contact, while fixing the drive rod. A movable arcing contact that can be driven along the axis of the arcing contact and a fixed arcing contact that can be freely fitted and removed is provided at the tip of the drive rod, and a movable main contact that can be freely fitted and removed from the fixed main contact is attached to the drive rod. By providing an insulating nozzle to cover the arcing contact, a closed gas chamber is formed within the insulating nozzle with only the insertion hole at the tip of the insulating nozzle opening, and gas is generated in the gas chamber by contact with the arc. It is characterized by the provision of an insulator.

When an arc is generated between the fixed arcing contact and the movable arcing contact during F1 action opening, the insulator in the insulating nozzle is evaporated by the heat of the arc and gas is generated.

This gas accumulates in the gas chamber and becomes highly pressurized, and when the fixed arcing contact is subsequently removed from the insertion hole of the insulating nozzle, it is discharged from the insertion hole to the outside of the insulating nozzle where the pressure is low. At this time, gas is blown onto the arc to extinguish it.

G. Examples Hereinafter, the present invention will be explained in detail based on examples shown in the drawings. Note that this embodiment is an improvement of a part of the conventional gas load switch, so the same parts as the conventional one are given the same reference numerals, the explanation is omitted, and only the different parts will be explained.

The configuration of the gas load switch according to the present invention will be explained based on FIGS. 1 to 3.

(11) First Embodiment A first embodiment is shown in FIG. As shown in the figure, a hole for forming a conventional discharge path is not formed on the end face of the drive rod 8, and thus a closed gas chamber 16 with only the insertion hole 11 open is formed in the insulating nozzle 13. . Then, the piston and the like that were conventionally present inside the hollow drive rod 8 are removed.

Inside the gas chamber 16, there is an insulating tube 17 for generating gas.
is provided to fill the space between the insulating nozzle 13 and the movable arcing contact 7.

With such a configuration, when an arc 15 is generated between the fixed arcing contact 4 and the movable arcing contact 7 during opening, the arc 15 touches the insulating tube 17 and gas evaporates from the insulating tube 17. This gas increases the pressure inside the gas chamber 16, and the fixed arcing contact 4 is inserted into the insertion hole 1! When the gas escapes from the insulating nozzle 13, the gas is discharged from the insertion hole 11 to the outside of the insulating nozzle 13 where the pressure is low, and at this time the arc 15 is extinguished. The magnitude of the load current that can be opened and closed is about 2000 to 3000A.

(b) Second Embodiment In the second embodiment, as shown in FIG. 2, arc! A bellows portion 18 is formed in the portion that contacts the arc 15 to increase the contact area with the arc 15.

As a result, the amount of gas evaporation from the insulating cylinder 17 increases,
The turbulent gas flow increases the arc length and improves arc extinguishing performance.

(c) Third Embodiment In the third embodiment, the gas chamber 16 is expanded to between the insulating nozzle 13 and the movable arcing contact 7, as shown in FIG.
The gas generation efficiency is increased by embedding the

Since the surface area of the insulator in contact with the arc is larger than in the first and second embodiments, the amount of gas evaporated is large, and the volume of the gas chamber 16 is also larger than in the first and second embodiments, so the amount of gas stored is also large. . Therefore, the arc extinguishing ability is improved.

H1 Effects of the invention As can be seen from the above explanation, the gas load switch according to the invention has the following effects.

(a) Since the configuration is such that a gas chamber is formed and an insulator is provided in the gas chamber, the gas generated from the insulator is blown onto the arc, so there is no need for a buffer chamber or piston, and the gas load switch can be made smaller. . Further, since no operating force is required to compress the insulating gas, the driving force of the drive rod can be reduced, and the driving means can be downsized.

(b) In a conventional gas load switch equipped with a buffer chamber, the pressure in the buffer chamber increases even when the load current is small, so a surge may occur due to a new phenomenon before the current zero point. However, in the present invention, since the evaporative gas of the insulator is used, the amount of gas generated varies depending on the current value, and appropriate arc extinguishing performance is obtained for each current value, resulting in a very low level of surge generation. Therefore, reliability against overvoltage is improved.

[Brief explanation of drawings]

1 to 3 relate to embodiments of the gas load switch according to the present invention, FIG. 1 is a sectional view of the first embodiment, FIG. 2 is a sectional view of the second embodiment, and FIG. 3 is a sectional view of the second embodiment. FIG. 4 is a cross-sectional view of a conventional gas load switch. 3... Fixed main contact, 4... Fixed arcing contact, 7... Movable arcing contact, 8...
- Drive rod, 11... Insertion hole, 13... Insulating nozzle, 14... Movable main contact, 16... Gas chamber,
17°19...Insulating tube. Fig. 3 Cross-sectional view of gas load switch (third embodiment) Cross-sectional view of gas load switch (conventional) Two other people

Claims (1)

[Claims] (1) A fixed arcing contact is fixed in an insulating gas, a fixed main contact is provided outside the fixed arcing contact, and a drive rod is provided so that it can be driven along the axis of the fixed arcing contact, so that the fixed arcing contact can be inserted and removed. A freely movable arcing contact is provided at the tip of the drive rod, a movable main contact that can be freely inserted into and removed from the fixed main contact is attached to the drive rod, and an insulated nozzle is provided to cover the movable arcing contact. A gas load switch characterized in that a closed gas chamber with only an insertion hole open is formed in an insulating nozzle, and an insulator that generates gas upon contact with an arc is provided in the gas chamber.