JP2604744Y2 - Gas circuit breaker - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-puffer type gas circuit breaker using a magnetic arc drive.

[0002]

2. Description of the Related Art As a technique for extinguishing a gas circuit breaker, a heat puffer type gas circuit breaker using a magnetic arc drive has been conventionally known. This will be described with reference to FIG. The left half of FIG. 3 shows a closed state of the circuit breaker, and the right half shows a state of the circuit breaker during a breaking operation. A boost chamber 3 is formed by the upper terminal 1 and the outer wall 2. The fixed contact 4, the coil 5, and the arc runner 6 are housed in the boosting chamber 3.
In addition, a nozzle 9 through which the movable contact 8 enters and exits the pressurizing chamber 3 is formed on the outer wall 2.

[0003] A movable contact 8 enters and exits the pressurizing chamber 3 from a nozzle 9 portion. When the circuit breaker is turned on, the movable contact 8 comes into contact with the fixed contact 4 in the pressurizing chamber 3, and at this time, the nozzle 9 is closed to seal the pressurizing chamber 3. When the current is cut off, the movable contact 8 separates from the fixed contact 4 and goes out of the boosting chamber 3 to release the inside of the boosting chamber to the outside of the boosting chamber.

The fixed contact 4 is electrically connected to the upper terminal 1 by a support rib 10 and is mechanically supported. The space between the support ribs 10 is a gas passage 11 through which gas can flow. The fixed contact 4, the coil 5, and the arc runner 6 are electrically connected in series. Next, the operation of the thermal puffer type gas circuit breaker using this magnetic arc drive will be described.

When the left half of the figure is energized, the current flows between the fixed contact 4 and the movable contact 8 by contact. When the circuit breaker is shut off, the movable contact 8 is moved downward in the figure by an operating mechanism (not shown). When the movable contact 8 separates from the fixed contact 4, the current is commutated to the path between the coil 5 and the arc runner 6, and an arc is generated between the arc runner 6 and the movable contact 8. The arc is driven to rotate at a high speed around the illustrated central axis by a magnetic field generated by a current flowing through the coil 5.

[0006] When the arc rotates inside the pressurizing chamber 3, the gas inside the pressurizing chamber 3 is heated to a high temperature, and the gas pressure increases. In addition, when the arc rotates, the gas is relatively blown to the arc to extinguish the arc, and the arc is extinguished by driving the magnetic arc. When the movable contact 8 is in the boosting chamber 3, the arc extinguishing action by the magnetic drive is performed.

Thereafter, when the movable contact 8 moves further downward and the tip of the movable contact 8 comes off from the nozzle 9 of the pressurizing chamber 3 as shown in the right half of FIG. As shown in (1), the liquid is rapidly ejected through the space between the nozzle 9 and the movable contact 8. With this gas flow, an arc extinguishing action is performed by a heat puffer that blows out the arc A generated between the arc runner 6 and the movable contact 8.

[0008]

In the breaking operation of the circuit breaker described above, the gas discharged from the boosting chamber 3 and blown to the arc must be a gas having insulation and arc extinguishing performance. However, when the time from opening to arc extinction becomes longer or the current becomes larger, the arc heats the gas abnormally, the insulation and arc extinction performance are lost, and the arc cannot be extinguished. there were.

An object of the present invention is to improve the arc extinguishing performance in a thermal puffer type gas circuit breaker using a magnetic arc drive.

[0010]

According to the present invention, in order to achieve the above object, a net-like or cotton-like cooling fin is provided at the upper part of a pressure-increasing chamber in a heat-puffer-type gas circuit breaker combined with a magnetic arc drive. The arrangement direction of the cooling fins is arranged in accordance with the rotation direction of the gas when driving the magnetic arc.

[0011]

According to the above-mentioned means, the gas heated and pressurized by the arc energy and accumulated in the pressurized chamber is deprived of heat by the cooling fins and cooled. For this reason, the gas discharged from the pressurizing chamber through the nozzle when the movable contact passes through the nozzle becomes a gas having a sufficient arc extinguishing performance, and the arc extinguishing performance is improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of the shut-off portion of the thermal puffer type gas circuit breaker as viewed from the side. FIG. 2 shows a cross section taken along line YY of FIG. The cut-off shown is
It is stored together with SF6 gas in a container (not shown).
The left half of the figure shows the closed state of the circuit breaker, and the right half shows the state of the circuit breaker at the time of interruption.

A boosting chamber 3 is formed by the upper terminal 1 and the outer wall 2. The fixed contact 4, the coil 5, and the arc runner 6 are housed in the boosting chamber 3. Further, a cooling fin 7 is provided in an upper part in the pressure increasing chamber 3. In addition, outer wall 2
Is formed with a nozzle 9 through which the movable contact 8 enters and exits the boosting chamber 3. The movable contact 8 enters and exits the pressurizing chamber 3 from the nozzle 9. When the circuit breaker is turned on, the movable contact 8 comes into contact with the fixed contact 4 in the boosting chamber 3,
At this time, the pressure chamber 3 is sealed by closing the nozzle 9. When the current is cut off, the movable contact 8 separates from the fixed contact 4 and goes out of the boosting chamber 3 to release the inside of the boosting chamber to the outside of the boosting chamber.

The fixed contact 4 is electrically connected to the upper terminal 1 by a support rib 10 and is mechanically supported. The space between the support ribs 10 is a gas passage 11 through which gas can flow. The fixed contact 4, the coil 5, and the arc runner 6 are electrically connected in series. The cooling fins 7 are made of a material having good thermal conductivity, such as aluminum or copper, and are arranged on the inner periphery of the outer wall 2 at an upper part of the boosting chamber 3 with a space between them as shown in FIG. Incidentally, the cooling fins 7 to use a net-like, cotton or the like. The cooling fins 7 are arranged to be inclined toward the center so that the gas smoothly flows between the cooling fins 7 in accordance with the direction in which the gas rotates in the magnetic arc driving. Further, the cooling fins 7 are preferably formed on a curved surface along the flow of the gas.

Next, the operation of the thermal puffer type circuit breaker using the magnetic arc drive will be described. When the left half of the figure is energized, the fixed contact 4 and the movable contact 8 come into contact with each other, and the current flows through the path of the upper terminal 1-the support rib 11-the fixed contact 4-the movable contact 8.

At the time of the breaking operation of the circuit breaker, the movable contact 8 is moved downward in the figure by an operating mechanism (not shown). When the movable contact 8 separates from the fixed contact 4, the current is diverted to the path of the upper terminal 1-the support rib 10-the coil 5-the arc runner 6, and an arc is generated between the arc runner 6 and the movable contact 8. The arc is driven to rotate at a high speed around the illustrated central axis by a magnetic field generated by a current flowing through the coil 5. Pressurizing room 3
When the arc rotates inside, the gas inside the pressurizing chamber 3 is heated to a high temperature, and the gas pressure is increased. Further, when the arc is driven in the gas, the gas is relatively blown to the arc, and the arc is extinguished by the magnetic arc drive. The movable contact 8 is the booster room 3
When it is within the range, the arc extinguishing action by the magnetic drive is performed.

During the above interruption operation, the gas in the pressurizing chamber 3 is heated by the arc energy and pressurized. In the early stage of arc generation, the pressurized gas is supplied to the fixed contact 4
Gas passage 11 formed between the hollow portion and the support rib 10
And flows into the pressurizing chamber 3. After the arc is transferred to the arc runner 6, the pressurized gas passes through the outer periphery of the coil 5 in the pressurizing chamber 3, passes through the gas passage 11, and passes through the hollow portion of the fixed contact 4.

Thereafter, when the movable contact 8 moves further downward and the tip of the movable contact 8 comes off the nozzle 9 of the pressurizing chamber 3 as shown on the right side in the figure, the high-pressure gas inside the pressurizing chamber 3 As shown by an arrow B, the gas suddenly blows out between the movable contacts 8. With this gas flow,
An arc extinguishing action is performed by a thermal puffer effect for blowing out the arc A between the arc runner 6 and the movable contact 8.

At this time, the gas blown to the arc is:
The gas is pressurized by the arc and accumulated in the pressurizing chamber 3. This gas is pressurized by the arc and is pushed up to the upper part in the pressurizing chamber 3. The gas is deprived of heat by the net-like or cotton-like cooling fins 7 , cooled and accumulated in the pressurizing chamber 3. In addition, a part of the gas accumulated by cooling is spread below the pressurizing chamber 3 and cools the gas heated by the arc. Therefore, when the movable contact 8 passes through the nozzle 9, the gas discharged from the pressurizing chamber 3 through the nozzle 9 is a gas having a sufficient arc extinguishing performance, so that the arc extinguishing performance is improved.

Further, since the volume of the gas heated by the arc is reduced by providing the cooling fins 7, the volume of the boosting chamber 3 can be reduced for a constant current, and the entire circuit breaker can be downsized. It is effective to do. Further, the cooling fins 7 are arranged so that the arrangement direction thereof is inclined with respect to the direction from the center of the pressurizing chamber 3 toward the outer wall 2, and the inclination direction matches the rotation direction of the gas driven by the magnetic arc. Fins 7 do not hinder the gas flow, and a smooth gas flow is obtained. For this reason,
The gas is cooled quickly, and the arc extinguishing performance is improved.

[0021]

According to the present invention, the arc extinguishing performance can be improved in a thermal puffer type gas circuit breaker using a magnetic arc drive.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a gas circuit breaker of the present invention.

FIG. 2 is a cross-sectional view as seen from the direction of the arrow YY in FIG. 1;

FIG. 3 is a cross-sectional view of a conventional gas circuit breaker.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Upper terminal 2 ... Outer wall 3 ... Boost chamber 4 ... Fixed contact 5 ... Coil 6 ... Arc runner 7 ... Cooling fin 8 ... Movable contact 9 ... Nozzle 10 ... Support rib 11 ... Gas flow path

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-276122 (JP, A) JP-A-50-132471 (JP, A) JP-A-3-98224 (JP, A) JP-A 53-1982 117774 (JP, A) Hikaru Hei 3-46939 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01H 33/98 H01H 33/18

Claims (1)

(57) [Scope of request for utility model registration] 1. A heat-puffer type gas circuit breaker combined with a magnetic arc drive, wherein a net-like or cotton-like shape is formed on the upper part of the inside of a pressure increasing chamber.
Wherein the cooling fins are arranged in such a manner that the arrangement direction of the cooling fins is aligned with the rotation direction of the gas when the magnetic arc is driven.