JPH04147528A - Buffer type gas blast circuit breaker - Google Patents

Abstract

PURPOSE:To reduce an area of a piston for receiving the pressure of the insulating gas to about 1/2 of the conventional area by forming a fixed hot gas chamber outside of a buffer chamber, and communicating a part near an opening of a flow passage with the fixed hot gas chamber. CONSTITUTION:A hole 27 is formed in a piston 17, and a ring check valve 28 is inserted to a driving rod 8. They are provided to take the insulating gas from the right side of the piston 17 into a buffer chamber 9 at the time of closing. A contact 29 is installed to a buffer cylinder 10 by springs 30 and while the inside end thereof abuts on the peripheral surface of the piston 17. They are provided to maintain continuity of the buffer cylinder 10 and the piston 17. The hot gas by an arc generated at the tin of cut-off is flowed to not only the buffer chamber 9 but also a fixed hot gas chamber 24 to make the pressure of both the chambers equal. An area of the piston 17 inside of the buffer chamber 9 for receiving the pressure from the hot gas becomes about 1/2 of the conventional area.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a buffer type gas circuit breaker that extinguishes an arc by blowing an insulating gas in a buffer chamber onto the arc.

The present invention provides a buffer gas circuit breaker configured to extinguish the arc by blowing an insulating gas onto the arc that is generated when the arc is interrupted, in which a fixed hot gas chamber is formed outside the buffer chamber so that the hot gas generated by the arc is extinguished. By setting it so that it moves not only to the buffer chamber but also to the fixed heat gas chamber, the driving force of the drive rod is reduced, making the buffer type gas circuit breaker lower in noise and smaller.
The aim is to reduce costs and improve reliability.

C8 Conventional technology A buffer type gas circuit breaker is used as a power circuit breaker.

The structure of a conventional buffer type gas circuit breaker is shown in FIG. As shown in the figure, the buffer type gas circuit breaker is composed of a fixed unit 1 and a movable unit 2 housed in a tank 6 filled with an insulating gas such as S Fa gas. The fixed unit l is a hollow cooling cylinder 2! , a plurality of fixed main contacts 3 provided at one end of the cooling cylinder 21, and a fixed arcing contact 4 provided at the center of the interior via a support portion 18. 20 is a conductor.

On the other hand, the movable unit 2 includes a drive rod 8 that is connected to a drive means via a connection shaft 5, has a movable arcing contact 7 at its tip, and is driven in the left-right direction in the figure.
A buffer cylinder 1O is integrally formed at the tip of the drive rod 8 and forms a buffer chamber 9 between the drive rod 8 and the buffer cylinder 10, which is fitted into the buffer cylinder 10 so as to cover the movable arcing contact 7, and is arranged in the middle. An insulating nozzle 13 having an insertion hole 11 for inserting the fixed arcing contact 4 therein and forming a flow path 12 between it and a flow path guide 7a placed over the movable arcing contact 7, and the tip of the buffer cylinder 10. The movable main contact 14 formed in
5 and is slidably provided between the drive rod 8 and the buffer cylinder 10 to form a buffer chamber 9.
and a piston 17 as suction/exhaust means for sucking in and discharging insulating gas. Note that 23 is a conductor. The reason why the contacts are divided into main contacts and arcing contacts is to distribute the functions so that they can be used properly.

In such a buffer type gas circuit breaker, the drive rod 8
When the insulating gas is driven to the left in the figure and inserted, insulating gas is sucked into the buffer chamber 9 through the insertion hole 11.

On the other hand, when shutting off, the situation is as follows. As shown in FIG. 4(a), before the fixed arcing contact 4 comes out of the insertion hole 11, the high temperature and high pressure hot gas generated by the arc 19 between the fixed arcing contact 4 and the movable arcing contact 7 enters the flow path. 12 and attempts to enter the buffer chamber 9. At this time, the buffer cylinder 10
On the other hand, the piston 17 moves relatively to the left and is in a state of pushing out the insulating gas in the buffer chamber 9, so that the resistance force applied to the piston 17 increases.

After this, as shown in FIG. 4(b), when the fixed arcing contact 4 is removed from the insertion hole 11, the arc 19 is attenuated, and the insulating gas in the buffer chamber 9 and the hot gas taken into the buffer chamber 9 are It is blown onto the arc 19 through the flow path 12 and extinguished it.

The insulating gas then flows into the cooling cylinder 21 through the insertion hole 11 and is cooled by the cooling cylinder 21 .

D1 Problems to be Solved by the Invention However, since all of the hot gas generated by the arc moves to the buffer chamber, there are the following problems.

Since the pressure in the buffer chamber increases, the resistance force when driving the drive rod becomes large, and the drive means equipped with the drive force to overcome this resistance becomes large.

In substations in residential areas, the noise level is high despite the demand for low noise, and the manufacturing cost of the buffer type gas circuit breaker is also high.

On the other hand, in order to improve performance, it is necessary to increase the pressure in the buffer chamber and increase the blowing speed of insulating gas, etc. to the arc, but if the resistance is large, the blowing speed cannot be increased, making it difficult to improve performance. is difficult.

Therefore, an object of the present invention is to provide a buffer type gas circuit breaker that solves the above problems.

86 Means for Solving the Problems The structure of the present invention to achieve the above object is to provide a cylindrical cooling cylinder to which one conductor is connected in a tank filled with insulating gas, and to A fixed main contact is provided on the inner peripheral surface of one end, and a fixed arcing contact is provided at the axial center position inside the fixed main contact via a support part, and the fixed arcing contact has a movable arcing contact at the tip that can be freely fitted and removed. A drive rod is provided so as to be movable along the axis of the movable arcing contact, a buffer cylinder having a movable main contact that is inserted into and removed from the fixed main contact is provided integrally at the tip of the drive rod, and the buffer cylinder and the drive rod are slidably connected to each other. A piston that is movable and forms a buffer chamber in the buffer cylinder is fixed in the tank and connected to the other conductor, and an insulating nozzle is provided to form a flow path outside the movable arcing contact for guiding the insulating gas in the buffer chamber. In the buffer type gas circuit breaker attached to the end face of the buffer cylinder, a fixed hot gas chamber is formed outside the buffer chamber, and the vicinity of the part where the flow path opens communicates with the fixed hot gas chamber. do.

When hot gas is generated by the arc generated during the first half of the F8 cut-off operation, this hot gas moves not only to the buffer chamber but also to the stationary hot gas chamber. Since the area to which pressure is applied to the piston in the buffer chamber is about 172 mm compared to the conventional one, the resistance force applied to the drive rod is also reduced to about 1/2, and a driving means with a smaller driving force than the conventional one can be used.

In the latter half of the interrupting operation, insulating gas etc. pushed out from the buffer chamber and hot gas expanded and released from the fixed hot gas chamber are blown onto the arc.

G. Examples Hereinafter, the present invention will be explained in detail based on examples shown in the drawings. Note that this embodiment is a partial improvement of the conventional buffer type gas circuit breaker, so the same parts as the conventional one are given the same reference numerals and explanations are omitted, and only the different parts will be explained.

(a) First Embodiment A first embodiment of the buffer type gas circuit breaker according to the present invention will be described with reference to FIG.

As shown in the figure, a fixed hot gas chamber 24 is formed outside the buffer chamber 9 at a position concentric with the buffer chamber 9. As a result, the conventional buffer chamber 9 is divided into two, the buffer chamber 9 and the fixed hot gas chamber 24 shown in FIG. A second flow path 25 is formed outside the flow path 12 to communicate the inside of the insertion hole 11 near the opening of the flow path 12 and the fixed hot gas chamber 24 . A second flow path guide 26 is provided between the insulating nozzle 13 and the flow path guide 7a to form the second flow path 25.
is provided, and the base end of the flow path guide 26 is fixed to the end surface of the buffer cylinder 10.

In addition, this embodiment differs from the conventional method in the following parts. A hole 27 is formed in the piston 17, and a ring-shaped check valve 2 is formed in the piston 17.
8 is inserted into the drive rod 8.

This is provided to introduce insulating gas into the buffer chamber 9 from the right side of the piston 17 in the figure when the piston 17 is turned on. A contact 29 is attached to the buffer cylinder 10 by a spring 30, and its inner end abuts against the outer peripheral surface of the piston 17. This is provided to maintain conduction between the buffer cylinder 10 and the piston 17. In addition, 31.32
is a sticker.

In such a buffer type gas circuit breaker, the hot gas caused by the arc generated at the time of disconnection flows not only into the buffer chamber 9 but also into the fixed hot gas chamber 24, and the pressures in both chambers become approximately equal. The area on which the piston 17 in the buffer chamber 9 receives pressure from the hot gas is about 1/2 or less of the conventional one. This means that
This means that the resistance force against the driving of the driving rod 8 is about 1/2 or less of that of the conventional one, and the driving force of the driving rod 8 can be reduced by that much, and it is sufficient to use a smaller driving means than the conventional one. .

Note that the pressure in the fixed hot gas chamber 24 does not affect the resistance force of the drive rod 8. Therefore, even if the hot gas generated by the arc 19 is taken into the fixed hot gas chamber and the pressure is increased, the driving force of the drive rod 8 is not affected much, and the amount of hot gas taken into the fixed hot gas chamber 24 is increased. It is also possible to improve the performance of the buffer type gas circuit breaker by increasing the

(b) Second Embodiment Next, a second embodiment of the buffer type gas circuit breaker will be described based on FIG.

In the second embodiment, in addition to the first embodiment, a ring-shaped check valve 33 for blocking the outlet of the buffer chamber 9 is provided in the flow path 12. The check valve 33 is provided by being inserted into the flow path guide 7a, and the second flow path guide 26 is provided to restrict the movement range.
The outer periphery is loosely fitted into a recess 34 formed on the inner periphery of the holder.

In such a buffer type gas circuit breaker, even if hot gas is generated due to the arc at the time of shutoff, the check valve 33 closes the outlet of the buffer chamber 9, so that the hot gas does not flow into the buffer chamber 9 much and most of it is fixed. It flows into the hot gas chamber 24. Therefore, the resistance force against the drive of the drive rod 8 is smaller than in the case of the first embodiment, and therefore a drive means with a smaller driving force than in the case of the first embodiment is sufficient.

When the pressure in the buffer chamber 9 increases in the later stages of the cutoff operation, the pressure in the buffer chamber 9 opens the check valve 33 and the insulating gas in the buffer chamber 9 is blown onto the arc, and at the same time, the fixed hot gas chamber 24 hot gas is also blown onto the arc.

H1 Effects of the invention As can be seen from the above explanation, the buffer type gas circuit breaker according to the invention has the following effects.

By providing a fixed hot gas chamber outside the buffer chamber,
The volume of the buffer chamber is about 172 compared to the conventional one, and the area of the piston that receives the pressure of the insulating gas is about 1/2 that of the conventional one, so the resistance force against driving the drive rod is about 1/2,
Driving force can be significantly smaller than before.

Therefore, it is possible to reduce the noise of the buffer type gas circuit breaker, and also to reduce the size of the buffer type gas circuit breaker, further reducing costs and improving reliability.

In other words, by leaving the drive means as conventional, the pressure in the buffer chamber 9 can be made higher than in the conventional case, and the arc extinguishing performance is improved.

[Brief explanation of the drawing]

1 to 2 relate to embodiments of the buffer type gas circuit breaker 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 FIGS. FIG. 4 relates to a conventional buffer type gas circuit breaker, and FIG. 3 is a sectional view of the buffer type gas circuit breaker, and FIG. 4(a). (b) is an action explanatory diagram. 3... Fixed main contact, 4... Fixed arcing contact, 6... Tank, 7... Movable arcing contact, 8... Drive rod, 9... Buffer chamber,
10...Buff unlinda, 12...Flow path, slur,
14... Movable main contact, 118... Support part, 2
0.23...Conductor, gas chamber, 25...-Second flow path. 13...Insulation Noah...Piston, 24...Fixed heat (a) Early stage of cut-off operation (b) Late stage of cut-off operation

Claims (1)

[Claims] (1) A cylindrical cooling cylinder with one conductor connected is provided in a tank filled with insulating gas, and a fixed main contact is provided on the inner peripheral surface of one end of the cooling cylinder. A fixed arcing contact is provided at the axial center position via a support part, and a drive rod having a movable arcing contact at its tip that can be freely fitted and removed from the fixed arcing contact is provided so that it can be driven along the axial center of the movable arcing contact. A buffer cylinder having a movable main contact that can be fitted into and removed from the contact is integrally provided at the tip of the drive rod, and a piston that is slidable between the buffer cylinder and the drive rod and forms a buffer chamber in the buffer cylinder is fixed in the tank. In a buffer type gas circuit breaker, an insulating nozzle is attached to the end face of the buffer cylinder to form a flow path outside the movable arcing contact that connects to the other conductor and guides the insulating gas in the buffer chamber. 1. A buffer type gas circuit breaker, characterized in that a fixed hot gas chamber is formed, and the vicinity of the opening of the flow path communicates with the fixed hot gas chamber.