JP2000040451A - Puffer gas blast circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a puffer gas blast circuit breaker which improves reliability by improving cut-off performance of a hybrid puffer arc extinguishing chamber, and by preventing foreign substances from coming up as well. SOLUTION: In a puffer gas blast circuit breaker which extinguishes an arc generating between a fixed contact and a moving contact by blasting gas, an operation rod 1 has a communicating hole to communicate with a puffer chamber in its first period of compression and communicate with gas space outside of the puffer chamber in its last period of compression. A resin ring without a cut and a slot with one open end to mount this ring are placed on a flange of a puffer piston 3 penetrated by the communicating hole of the operation rod 1. Since the open end is sealed by a metal guide, there is no directional dependency on setting of the operation rod and the ring, and the air tightness of the gas sealing part of the sliding part between the puffer piston 3 and the operation rod 1 is improved wherever the communication hole may be in the ring. Thereby, the pressure in the puffer chamber is increased, and cut-off performance can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a puffer type gas circuit breaker.

[0002]

2. Description of the Related Art A so-called double flow type arc extinguishing chamber and a hybrid puffer type arc extinguishing chamber are used as the arc extinguishing chamber of a conventional puffer type gas circuit breaker. First, the double flow type arc extinction chamber of the puffer type gas circuit breaker will be described with reference to FIG.

[0003] As shown in the figure, the double-flow type arc extinguishing chamber of the puffer type gas circuit breaker has a hollow inside and an operating rod 1 having a communication hole for communicating the inside with the outside of the puffer chamber.
And a puffer cylinder 2 having one end fixed to the operation rod 1 and driven integrally therewith, and a puffer piston 3 inserted coaxially with the operation rod 1, and the puffer piston 3 insulates the inside of the puffer cylinder 2. The gas is compressed, and the compressed gas is blown from a nozzle 10 to the arc generated between the fixed arc contact 9 and the movable arc contact 8 at the tip of the puffer cylinder, and the hot gas generated at that time is blown from the hollow portion of the operating rod 1. It is configured to discharge to the outside of the puffer chamber through the communication hole. Reference numeral 7 denotes a resin ring with a step cut, 11 denotes a movable main contact, and 12 denotes a fixed main contact.

Next, a hybrid puffer type arc extinguishing chamber of a puffer type gas circuit breaker will be described with reference to FIG. As shown in the figure, a hybrid puffer type arc extinguishing chamber of a puffer type gas circuit breaker has an operating rod 1 having a communication hole in which a contact side is hollow from an intermediate portion and having a communication hole for communicating between the inside and the outside of the rod. Puffer piston 3 inserted coaxially
And a puffer cylinder 2 having one end fixed to the operation rod 1 and driven integrally therewith. The insulating gas in the puffer cylinder 2 is compressed, and the compressed gas is compressed by the nozzle 10 into a fixed arc at the tip of the puffer cylinder. The arc generated between the contact 9 and the movable arc contact 8 is blown, and the hot gas generated at that time is discharged from the hollow portion of the operating rod 1 to the outside of the puffer chamber through the communication hole. In the process of compressing the insulating gas in the puffer cylinder 2,
In the early stage of compression, the hot gas blown to the arc is taken into the puffer chamber from the hollow portion of the operating rod 1 through the communication hole, and the pressure in the puffer chamber is increased by using the hot gas. The operation rod 1 is configured to be discharged from the hollow portion to the outside of the puffer chamber through the communication hole. Reference numeral 7 denotes a resin ring with a step cut, 11 denotes a movable main contact, and 12 denotes a fixed main contact.

As described above, in the puffer type gas circuit breaker,
The higher the pressure of the compressed gas in the puffer cylinder that blows out the arc to extinguish the arc, the higher the breaking performance of the circuit breaker, so the groove provided on the puffer piston side to improve the airtightness in the puffer cylinder As shown in FIG. 7, a configuration is adopted in which a resin ring 7 with a step cut is inserted and the airtightness of the sliding portion between the puffer piston 3 and the operation rod 1 is increased.

In the above-described double-flow arc extinguishing chamber and hybrid puffer-type arc extinguishing chamber, when the speed of the sliding portion between the puffer piston 3 and the operating rod 1 increases in the breaking operation, the frictional force of the sliding portion is reduced. Since there is a possibility that abnormal heat such as abnormal heat generation or galling may occur, a resin ring 7 is provided on the sliding portion between the puffer piston 3 and the operating rod 1.
To reduce the frictional force of the sliding part.

In general, the higher the pressure applied to the arc, the higher the breaking performance of the circuit breaker. Therefore, a hybrid puffer type arc-extinguishing chamber capable of effectively increasing the pressure in the puffer cylinder 2 using arc energy is provided. The breaking performance is improved compared to the double-flow arc-extinguishing chamber.

[0008]

As described above, in the case of the puffer type gas circuit breaker, when the speed of the sliding portion between the puffer piston and the operating rod increases, the frictional force of the sliding portion is reduced as much as possible. It is necessary to insert a resin ring with low frictional resistance.

However, in the conventional structure of the puffer type gas circuit breaker, since the ring groove is provided in the puffer piston, the ring is inserted into a resin-made gas circuit breaker unless the ring has a cut portion such as a ring with a step cut. The ring cannot be inserted into the ring groove due to its hardness.

In a conventional hybrid puffer type arc extinguishing chamber, if a resin ring with a step cut is used for the sliding portion between the puffer piston and the operation rod, the communication hole passes through the resin ring when the operation rod slides. As a result, the cut portion of the ring may be caught on the end of the communication hole, and the caught portion may be cut off, and it is expected that foreign matter is generated as much as the ring is cut off.

Therefore, it is necessary to increase the compression speed of the puffer cylinder so that a predetermined puffer pressure is obtained by providing a gap in advance without providing the sliding portion and taking into account the amount of gas leaking from the gap in advance. The performance of the original hybrid puffer type arc extinguishing chamber cannot be fully utilized. Further, if the ring is not used, the compressed gas in the puffer cylinder easily leaks from the sliding portion between the puffer piston and the operation rod, and thus there is a problem that the pressure of the compressed gas in the puffer chamber is prevented from rising.

Therefore, it is necessary to assemble the ring while taking care that the cut portion of the ring does not coincide with the communication hole provided in the operation rod. there were.

The present invention (corresponding to claims 1 and 2) provides
The purpose of the present invention is to solve the above-mentioned problem, and the purpose is to form a ring groove provided on a puffer piston with a puffer piston and a guide, and to make a resin portion having no cut portion in a sliding portion between the puffer piston and an operation rod. A puffer-type gas circuit breaker that has a structure in which the ring can be easily assembled, improves the efficiency of increasing the puffer pressure in the hybrid puffer-type arc-extinguishing chamber, and improves the shutoff performance. Is to provide.

[0014]

In order to achieve the above object, a first aspect of the present invention has a fixed contact and a movable contact which can be brought into and separated from a closed container filled with an arc-extinguishing gas. An operation rod provided on the movable contact side, a puffer piston provided outside the operation rod, a puffer cylinder having a tip fixed to the operation rod, and the puffer cylinder driven by driving the puffer cylinder. In a puffer type gas circuit breaker in which an insulating gas in a puffer chamber composed of a piston and the puffer cylinder is compressed and blown to an arc generated between the fixed contact and the movable contact to extinguish the arc, the operating rod is provided in the puffer chamber. A communication hole communicating with the puffer chamber is provided at an early stage of compression, and a communication hole communicating with a gas space outside the puffer chamber is provided at a later stage of compression, and the operation lock on a contact side of the communication hole is provided. The a hollow portion, the flange portion of the puffer piston hollow portion is closed by the communicating hole end opposite the contact, the communication holes of the operating rod passes,
A resin ring having no cut portion for holding the slide of the operating rod and a groove open on one side so that the ring can be inserted therein, and the puffer cylinder is sealed so that the open one end is sealed with a metal guide. Characterized in that it is configured to be fixed to

According to the first aspect, a puffer piston which is hollow at least in front of the intermediate portion and which is coaxially inserted with an operation rod having a communication hole through which the inside and the outside communicate, and a puffer cylinder driven by the operation rod A ring groove having a resin ring having no cut portion and a guide for holding the ring is formed by a flange portion of the puffer piston and guide parts. Further, since the guide is attached to the puffer piston after the ring is inserted into the ring groove, the ring having no cut portion can be easily incorporated into the sliding portion between the puffer piston and the operating rod. And since a resin ring without a cut part can be used, the mounting direction between the operating rod and the ring is lost, and the gas seal at the sliding part between the puffer piston and the operating rod is no matter where the communication hole comes in the ring. It is possible to improve the airtightness of the part, improve the pressure rise in the puffer chamber, and improve the blocking performance.

According to a second aspect of the present invention, in the puffer-type gas circuit breaker according to the first aspect, the resin ring having no cut portion is inserted into a metal guide having one open end. One open end is closed by a flange portion of the puffer piston, and is fixed integrally with the puffer piston so as to be fitted. According to the second aspect, by inserting the ring on the guide side first, a resin ring having no cut portion can be easily incorporated.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a movable portion of a hybrid puffer type arc-extinguishing chamber according to a first embodiment (corresponding to claim 1) of the present invention, and FIG. 2 is a detailed view of a communication hole portion of an operation rod of FIG.

In FIG. 1, a hybrid puffer type arc extinguishing chamber according to the present embodiment has an operating rod 1 having a communication hole 6 at least in front of an intermediate portion and having a communicating hole 6 for communicating between the inside and the outside of the rod, and coaxially with the operating rod 1. A puffer piston 2 into which a resin ring 4 having no cut portion can be inserted, a puffer cylinder 3 driven integrally with the operating rod 1, a resin ring 4 having no cut portion, and a guide 5 for holding the ring 4 The ring groove for inserting the resin ring 4 having no cut portion is formed by the flange portion of the puffer piston 2 and the guide 5.

Next, the shut-off operation of this embodiment will be described. An operation rod 1 having a communication hole 6 through which at least a front side of the intermediate portion is hollow and the rod inside and outside communicate with each other; a puffer piston 2 inserted coaxially with the operation rod 1;
In the process of compressing the insulating gas in the puffer cylinder 3 by the operation rod 1 and the puffer cylinder 3 driven integrally, in the initial stage of the compression, the hot gas blown to the arc generated at the contact portion at the tip of the puffer cylinder 3 Is taken into the puffer chamber from the hollow portion of the operating rod 1 through the communication hole 6, and in the latter stage of the compression, the communication hole 6
Through the puffer chamber. The communication hole 6 passes through the resin ring 4 when the operation rod 1 slides.

According to the present embodiment, the simplest ring groove is formed by the guide 5 having a simplified shape and the flange portion of the puffer piston 2, but before the ring groove is formed, a resin material having no cut portion is formed. Since the ring 4 is inserted into the flange portion of the puffer piston 2 and then the guide 5 is attached to form a ring groove, the operating rod 1 provided with the communication hole 6 slides and the communication hole 6 passes. However, the ring 4 having no cut portion and the end of the communication hole 6 can slide without being caught,
Moreover, the gas compressed in the puffer cylinder can be sealed by the ring 4 having no cut portion. Therefore, it is possible to improve the pressure increasing efficiency in the puffer chamber and improve the shutoff performance, and at the same time, suppress the generation of foreign substances and improve the reliability.

FIG. 3 is a sectional view of a main part of a second embodiment (corresponding to claim 2) of the present invention. In the figure, the hybrid puffer type arc extinguishing chamber of the present embodiment has an operation rod 1 having a communication hole 6 which is hollow at least on the front side of an intermediate portion and communicates the inside and the outside, and is inserted coaxially with the operation rod 1. It has a puffer piston 2, a puffer cylinder (not shown) driven integrally with the operation rod 1, a resin ring 4 having no cut portion, and a guide 5 for inserting the ring 4 into the cut portion. A ring groove for inserting the resin ring 4 is formed by the flange portion of the puffer piston 2 and the guide 5. Since the shut-off operation of this embodiment is the same as that of the hybrid puffer type arc-extinguishing chamber of the first embodiment, description thereof will be omitted.

According to this embodiment, the puffer piston 2 is inserted after the resin ring 4 having no cut portion is inserted into the guide 5.
In order to attach the guide 5 to the flange portion, the operating rod 1 provided with the communication hole 6 slides, and even if the communication hole 6 passes, the ring 4 having no cut portion and the end of the communication hole 6 are caught. Ring 4 that can slide without any cuts
Thereby, the gas compressed in the puffer cylinder can be sealed. Therefore, it is possible to improve the pressure increasing efficiency in the puffer chamber and improve the shutoff performance, and at the same time, suppress the generation of foreign substances and improve the reliability.

FIG. 4 is a sectional view of a main part of a third embodiment (corresponding to claim 2) of the present invention. As shown in the drawing, in the present embodiment, the structure of the guide 5 is changed, that is, by making the lateral width of the guide larger than the flange of the puffer piston 2, the flange of the puffer piston 2 is made larger than that of the first embodiment of FIG. Since the ring width can be increased without reducing the surface pressure applied to the ring, the reliability of the sliding portion can be further improved as compared with the first embodiment.

The same effect can be obtained by applying the present invention not only to the hybrid puffer type arc extinguishing chamber but also to the double flow type arc extinguishing chamber. Further, the same applies to a so-called dual-motion type arc-extinguishing chamber in which a conventional fixed contact moves in conjunction with a movable contact.

[0025]

As described above, the present invention (Claim 1)
According to the present invention, a resin ring having no cut portion can be easily assembled into a ring groove formed by a flange portion and a guide of a puffer piston, so that sliding between the puffer piston and the operation rod can be achieved. The airtightness of the gas seal part of the moving part is increased, the pressure rise in the puffer chamber of the hybrid puffer type arc extinguishing chamber is improved, and the shutoff performance can be improved. In addition, the generation of foreign substances is suppressed, and the assembly workability is further improved. Thus, a puffer type gas circuit breaker with improved reliability can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is a detailed view of a communication hole portion of the operation rod of FIG. 1;

FIG. 3 is a sectional view of a main part of a second embodiment of the present invention.

FIG. 4 is a sectional view of a main part of a third embodiment of the present invention.

FIG. 5 is a cross-sectional view of a conventional double-flow arc extinguishing chamber.

FIG. 6 is a sectional view of a conventional hybrid puffer type arc extinguishing chamber.

FIG. 7 is a cross-sectional view showing an inserted state of a conventional ring with a step cut.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Operation rod, 2 ... Puffer cylinder, 3 ... Puffer piston, 4 ... Resin ring without cut part, 4A ... Wide resin ring without cut part, 5 ... Guide, 6 ...
Communication hole, 7… Resin ring with step cut, 8…
Movable arc contact, 9: fixed arc contact, 10: nozzle, 11: movable arc main contact, 12: fixed main contact.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takeo Toyoda 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture F-term in the Toshiba Hamakawasaki Plant (reference) 5G001 AA11 CC03 DD03 DD06 EE01 FF03 GG14

Claims (2)

[Claims] 1. An operation rod provided on a movable contact side, comprising: a fixed contact and a movable contact which can be brought into contact with and separated from a closed container filled with an arc-extinguishing gas; A puffer piston provided, a puffer cylinder the tip of which is fixed to the operation rod; and a puffer cylinder driven to drive the puffer piston and the puffer cylinder to compress an insulating gas in a puffer chamber to thereby form the fixed contact. And a puffer type gas circuit breaker that blows out an arc generated between the movable contacts and extinguishes the arc.
The operation rod communicates with the puffer chamber in the initial stage of compression of the puffer chamber, and has a communication hole communicating with the gas space outside the puffer chamber in the latter stage of compression, and the operation rod on the contact side of the communication hole is a hollow part. This hollow portion is closed at the end of the communication hole on the opposite side of the contact, and the flange portion of the puffer piston through which the communication hole of the operation rod passes has no cut portion that holds the sliding of the operation rod. It is characterized in that a resin ring and a groove having one side opened so that the ring can be inserted therein are provided, and the opened one end is fixed to the puffer cylinder so as to be sealed with a metal guide. Puffer type gas circuit breaker. 2. The puffer type gas circuit breaker according to claim 1, wherein the resin ring having no cut portion is inserted into a metal guide having an open one end, and one open end of the metal guide is connected to the puffer. A puffer type gas circuit breaker, which is fixed integrally with a puffer piston so as to close and fit with a flange portion of the piston.