JPH08111151A - Puffer type gas-blast circuit-breaker - Google Patents

Abstract

PURPOSE: To provide a highly reliable puffer type gas-blast circuit-breaker by which blowout of high temperature gas at large electric current breaking time can be prevented by preventing gas leakage of a gas passage. CONSTITUTION: A puffer type gas-blast circuit-breaker is formed in such a structure that a cylindrical part with which an insulating nozzle 5 is continued in the circumferential direction where a notch groove is omitted and a foot part 6a extending in a radial shape from a root part of a cover 6 are sandwiched by a presser 7, and are compressed and fixed to a puffer cylinder, and are tightly fastened together, and are brought into close contact with each other. Therefore, since airtightness of a gas passage part 8 can be sufficiently held, pressure of a puffer chamber 3 can be effectively used, and gas leakage can be prevented, and breaking performance can be siginificantly improved, and a highly reliable gas-blast circuit breaker can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas circuit breaker, and more particularly to a puffer type gas circuit breaker in which the structure of the gas blowing portion of the circuit breaker is improved.

[0002]

2. Description of the Related Art Generally, a puffer-type gas circuit breaker compresses an arc-extinguishing gas in a puffer chamber made up of a puffer cylinder and a piston in association with the opening and closing action of a contact made up of a stator and a mover. The generated gas is blown to the arc generated in the opening of the contact to extinguish the arc. In order to improve the breaking performance, it is important to raise the pressure of the puffer chamber to an appropriate level and efficiently guide the arc-extinguishing gas to the nozzle to spray it on the arc.

FIG. 6 is a cross-sectional view showing the process of shutting off a puffer type gas circuit breaker according to the prior art. Puffer cylinder 1
And the fixed piston 2 form a puffer chamber 3, and the puffer cylinder 1 is provided with a mover 4, an insulating nozzle 5, and a cover 6. Reference numeral 7 denotes a holding metal fitting for attaching the insulating nozzle 5 and the cover 6 to the puffer cylinder 1, which can also be used as a main contact for energization. The puffer cylinder 1 is provided with a plurality of gas supply ports 9 communicating with a flow path 8 formed between the insulating nozzle 5 and the cover 6. Reference numeral 10 denotes a stator that can be brought into contact with and separated from the mover 4.

As shown in the perspective view of FIG. 8, the cover 6 has a plurality of radially extending legs 6a having a root portion.
Further, as shown in the perspective view of FIG. 7, there are a plurality of circumferentially notched grooves 5a in the mounting portion of the insulating nozzle 5, which are assembled so as to mesh with the legs 6a of the cover 6.

Known as puffer-type gas circuit breakers of this type are Japanese Utility Model Laid-Open No. 59-95545, Japanese Patent Laid-Open No. 1-243328, Japanese Utility Model Laid-Open No. 56-61945, and the like.

[0006]

The puffer-type gas circuit breaker has a structure in which if a gap is present between the structures in the gas flow path extending from the puffer chamber to the nozzle, high-temperature gas leaked by an arc and the breaking performance will be deteriorated. This will cause a large decrease.

In the recent gas circuit breakers, the high voltage and current per break point has been increasing, and the pressure in the puffer chamber is higher than in the past. It is very difficult to make the engagement portion between the groove 5a of the insulating nozzle 5 and the foot 6a of the cover 6 airtight, and when a large current is interrupted, high temperature gas is jetted out from a small gap, which causes However, there is a problem in that the insulation between the contacts is significantly reduced.

An object of the present invention is to provide a highly reliable gas circuit breaker, which has a structure in which the gas passage in the insulating nozzle is made airtight to improve the breaking performance.

[0009]

[Means for Solving the Problems] The above-mentioned object is to form a cylindrical portion which is continuous in the circumferential direction in which a notch groove is omitted in a mounting and fixing portion of an insulating nozzle, and which is tightly tightened and tightly attached to a puffer cylinder by a nozzle retainer. This is achieved by adopting a structure that

[0010]

By using the above means, the adhesion between the insulating nozzle and the cover and the puffer cylinder is improved, the gas flow path is kept airtight, and the gas in the puffer chamber can be effectively blown to the arc. .

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a midway of a puffer type gas circuit breaker according to an embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 6 indicate the same or corresponding portions. 2 is a view taken along the line AA of FIG. 1, and FIG. 3 is a perspective view of the cover 6.

To explain the new function of the present invention, the leg portion 6a of the cover 6 has a tapered outer peripheral portion as shown by 6b, and the contact surface of the insulating nozzle 5 engaged therewith has substantially the same inclination. The taper is formed. That is, the mounting and fixing portion of the insulating nozzle 5 is the cutout groove 5 shown in FIG.
It is formed in a cylindrical shape without a. The inner shape side of the base portion of the cover 6 is configured to be in close contact with the outer shape side 4a of the base portion of the mover 4.

FIG. 4 is an exploded cross-sectional view for explaining this embodiment in detail, and shows a part of FIG. 1 in an enlarged manner. Insulation nozzle 5
The length of the engaging part between the mounting and fixing part of the
When the nozzle presser 7 is fixed to the puffer cylinder 1 by tightening it with the bolts 11, the insulating part of the insulating nozzle 5 is used as the fixing part insulator. A certain engaging portion length L1 is compressed and deformed to the same length as the length L2 of the nozzle retainer 7 and comes into close contact with the puffer cylinder 1, and the nozzle retainer 7 comes into contact with the puffer cylinder 1 and is fixed in a state in which current can flow. . By compressing and deforming the length L1 of the fixed portion of the insulating nozzle 5, the insulating nozzle 5 and the puffer cylinder 1 can be fixed while maintaining airtightness. Further, the foot portion of the cover 6 is pressure-fixed to the puffer cylinder 1 by the insulating nozzle 5 via the tapered portion 6b. Here, the foot portion 6a is pressed by pressing the taper portion 6b.
Is applied in the direction of the inner diameter, but the outer peripheral side 4a of the base of the mover 4 is effective in preventing the cover 6 from being deformed by the component. The bolt 12 is fixed to the puffer cylinder 1 and is aligned with the recess 6C of the cover 6 to regulate the position.

In FIG. 4, the mover 4 and the puffer cylinder 1 are shown.
However, in the case of another structure, for example, when the mover 4 and the puffer cylinder 1 are fixed at a position corresponding to the bolt 12, the mounting bolt can also be used as a position restriction. Further, the position can be regulated by providing bolts or unevenness on the inner side of the cover 6 and a part of the outer shape side of the mover 4.

FIG. 5 shows a partially exploded view of another embodiment of the present invention. A groove 5b is provided in a portion of the insulating nozzle 5 that engages with the foot portion 6a of the cover 6. This groove 5b is different from the cutout portion 5a shown in FIG. That is, the insulating nozzle 5
The groove 5b is formed into a cylindrical stepped shape that is continuous in the circumferential direction and does not communicate with the outside. Here, the engagement portion length L4 of the stepped groove 5b of the insulating nozzle 5 is set to be slightly shorter than the length L3 of the foot portion 6a. The relationship between L1 and L2 is the same as in the case of FIG. Therefore, when the insulating nozzle 5 and the cover 6 are attached to the puffer cylinder 1 by crimping with the nozzle retainer 7, the insulating nozzle 5 is compressed by the nozzle retainer 7 and closely adheres to the puffer cylinder 1, and at the same time, the foot 6a of the cover 6 is insulated. Since it is pressed by the groove 5b of No. 5 and is closely attached to the puffer cylinder 1, gas leakage can be completely prevented.

An insulating material is generally used as the material of the cover 6, but a metal or a semiconductor material may be used.

[0017]

According to the present invention, since the gas flow path can be kept airtight, the pressure in the puffer chamber can be effectively used and the leakage of high temperature gas can be prevented, so that the large current interruption performance is improved. A highly reliable circuit breaker can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a process of shutting off a puffer type gas circuit breaker according to an embodiment of the present invention.

FIG. 2 is an AA direction view of FIG.

FIG. 3 is a perspective view of a cover 6.

FIG. 4 is an exploded cross-sectional view for explaining a part of FIG. 1 in detail.

FIG. 5 is a partial exploded view of another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing an intermediate state of the puffer type gas circuit breaker according to the conventional example.

7 is a perspective view of the insulating nozzle of FIG.

FIG. 8 is a perspective view of the cover of FIG.

[Explanation of symbols]

1 ... Puffer cylinder, 2 ... Piston, 3 ... Puffer chamber, 4 ... Mover, 5 ... Insulation nozzle, 6 ... Cover, 7 ... Nozzle retainer, 8 ... Flow path, 9 ... Air supply port, 10 ... Stator, 11
… Bolts, 12… bolts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Ishikawa 7-1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Yukio Kurosawa 7-chome, Omika-cho, Hitachi-shi, Ibaraki No. 1 Hitachi Ltd., Hitachi Research Laboratory (72) Inventor Kunio Hirasawa 1-1-1, Kokubun-cho, Hitachi-shi, Ibaraki Hitachi Kokubun Plant, Hitachi Ltd.

Claims (6)

[Claims] 1. A contactor composed of a pair of relatively separable stator and mover, a puffer chamber formed of a movable puffer cylinder and a fixed piston for connecting the mover to the tip, and the mover. A cover that surrounds and is attached to the tip of the puffer cylinder, and a flow path that surrounds the cover and that guides the arc-quenching gas from the puffer chamber that is attached to the tip of the puffer cylinder to the contactor. And an insulating nozzle for forming a puffer-type gas cutoff, which is arranged to compress the arc-extinguishing gas in the puffer chamber in relation to the opening / closing operation of the contact and to blow it to the arc generated between the contacts. In the container, an insulating nozzle in which a mounting and fixing portion as the insulating nozzle is formed in a cylindrical shape continuous in a circumferential direction with an outer diameter larger than an outer diameter of a foot portion radially extending from a root portion of the cover. And a ring-shaped presser for compressing and fixing to the puffer cylinder by sandwiching the mounting and fixing part of the insulating nozzle and the foot part radially extending from the base part of the cover. vessel. 2. The puffer-type gas circuit breaker according to claim 1, wherein an engagement portion length of the insulating nozzle mounting and fixing portion and the presser foot is slightly longer than an engagement portion length of the presser foot. A puffer type gas circuit breaker characterized by being set so that 3. The puffer-type gas circuit breaker according to claim 1, wherein a contact taper portion is provided at an engagement portion between a mounting and fixing portion of the insulating nozzle and a foot portion of the cover. Circuit breaker. 4. The puffer-type gas circuit breaker according to claim 1, wherein a cylinder that is continuous in the circumferential direction does not communicate with the outside at the engaging portion of the mounting and fixing portion of the insulating nozzle with the foot portion of the cover. A stepped groove is provided, and the engagement length of the stepped groove and the foot portion of the cover is set so that the engagement portion length of the stepped groove is slightly shorter than the engagement portion length of the cover foot portion. Characteristic puffer type gas circuit breaker. 5. The puffer-type gas circuit breaker according to claim 1, wherein a portion that comes into contact with the outer shape side portion of the mover is provided on the inner diameter side of the cover opposite to the portion that engages with the insulating nozzle. Characteristic puffer type gas circuit breaker. 6. The puffer-type gas circuit breaker according to claim 1, wherein one or more positioning means is provided between the cover and the puffer cylinder or the mover.