JPH0722836Y2 - Puffer type gas circuit breaker - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a puffer-type gas circuit breaker, and more particularly to a structure of an arc-extinguishing chamber capable of satisfactorily handling small current cutoff to large current cutoff.

"Prior Art" Generally, a puffer type gas circuit breaker includes a pair of fixed contact and movable contact that can be separated, and the separation of the movable contact in a container filled with arc-extinguishing gas of a single pressure. And a puffer device that compresses the arc extinguishing gas by operation. Then, the arc extinguishing gas compressed by the puffer device is blown onto the arc generated between the fixed contact and the movable contact to perform the breaking operation.

FIG. 5 shows an example of a puffer type gas circuit breaker according to this type of prior art. In a container 2 filled with a single pressure arc-extinguishing gas 1, a fixed contactor 3 and a discharge port 4a are provided. A movable contactor 4 is provided which includes a hollow portion 4b having a movable contactor 4 which reciprocates linearly by an operating mechanism (not shown) to contact and separate from the fixed contactor 3. The puffer device 5 is an air supply port
A cylinder 6 having 6a and connected to the outer peripheral portion of the movable contact 4, a piston 7 fixedly formed and slidable on the inner surface of the cylinder 6, and the cylinder 6 and the piston 7. And a puffer chamber 8 to be used. Reference numeral 9 is an insulating nozzle for guiding the arc extinguishing gas 1 from the puffer device 5, which is fixed to the cylinder 6 and is formed so as to surround the movable contactor 4.

The shutoff operation of the puffer type gas circuit breaker is performed by moving the movable contact 4 to the right by an operation mechanism (not shown).
As shown in FIG. 5, the tip of the movable contactor 4 is separated from the fixed contactor 3, and an arc is generated between the movable contactor 4 and the fixed contactor 3. Since the cylinder 6 is connected to the movable contactor 4, it moves rightward together with the movable contactor 4, and the arc-extinguishing gas 1 in the puffer chamber 8 formed by the cylinder 6 and the piston 7 is compressed. To be done. The compressed arc-extinguishing gas 1 flows out from the air supply port 6a, passes through the insulating nozzle 9, and flows toward the fixed contact 3 side and the gas flow A toward the hollow portion 4b of the movable contact 4. The arc is extinguished by being divided into B and sprayed on the arc. The movable contact 4
The gas flow B toward the hollow portion 4b passes through the hollow portion 4b and is discharged from the discharge port 4a.

[Problems to be Solved by the Invention] The puffer type gas circuit breaker having the above configuration is very suitable for cutting a large current. That is, when a large current of tens of thousands of amperes is cut off, the arc energy of the arc generated between the fixed contact 3 and the movable contact 4 becomes enormous.
The arc-extinguishing gas 1 becomes hot and, as a result, becomes extremely high in pressure. Since the arc-extinguishing gas 1 having a high pressure becomes a gas flow A toward the fixed contact 3 side and a gas flow B toward the hollow portion 4b of the movable contact 4, the arc is blown to the arc and discharged.
The flow velocity is also high, and the arc is extinguished well.

However, when the small current is cut off, the arc energy of the arc generated between the fixed contact 3 and the movable contact 4 is minute, and the arc-extinguishing gas 1 does not have a high pressure. As a result, the gas flow of the arc extinguishing gas 1 depends only on the gas pressure by the puffer device 5. Therefore, as described above, the gas flow A toward the fixed contactor 3 side and the hollow portion of the movable contactor 4
When the gas flow B is divided into the gas flow B toward 4b, the flow velocities of the gas flows A and B are reduced, so that the arc does not act effectively.

"Means for solving the problem" The present invention forms both a gas flow toward the fixed contact side and a gas flow toward the hollow portion of the movable contact in the case of large current interruption, while in the case of small current interruption The object of the present invention is to solve the above-mentioned drawbacks of the prior art by forming only the gas flow toward the fixed contact side, and the pressure of the gas flow toward the hollow part inside the hollow part of the movable contact. If the value is less than a certain value, the hollow portion is closed, and if it is more than a certain value, a valve device is provided.

"Operation" When the large current is cut off, the arc-extinguishing gas has a high pressure, so the pressure of the gas flow toward the hollow part of the movable contact also becomes a high pressure above a certain value, and the valve device operates to move the movable contact. A gas flow is formed towards the hollow part of the. Therefore, both the gas flow toward the fixed contact side and the gas flow toward the hollow portion of the movable contact are formed, and arc extinguishing is effectively performed.

On the other hand, in the case of a small current interruption, the arc-extinguishing gas does not have a high pressure, so the pressure of the gas flow toward the hollow portion of the movable contact is less than a certain value. Therefore, since the valve device does not operate, the hollow portion of the movable contact is closed by this valve device,
No gas flow is formed towards this hollow. As a result, only the gas flow toward the fixed contact is formed, so that the flow velocity of this gas flow can be maintained at a predetermined value, and the small current cutoff can be effectively performed.

"Embodiment" Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. It should be noted that the same parts as those of the above-mentioned conventional technique are denoted by the same reference numerals and the description thereof will be omitted. Further, FIG. 1 shows a closed state, FIG. 2 shows a state in which a large current is being interrupted, and FIG. 3 shows a state in which a small current is being interrupted.

In these drawings, a valve that closes the hollow portion 4b of the movable contactor 4 when the pressure of the gas flow B toward the hollow portion 4b is less than a certain value and opens when the pressure of the gas flow B toward the hollow portion 4b is more than a certain value. A device 10 is provided. That is, in the valve device 10, the valve 12 is locked to the other end of the spring 11 having one end fixed, and the valve 12 is configured to be movable left and right with the discharge port 4a interposed therebetween. When the pressure of the gas flow B toward the hollow portion 4b is less than a certain value, the spring 11 is in the extended state and the valve 12 is located on the left side of the discharge port 4a to close the hollow portion 4b and the gas flow B When the pressure of exceeds a certain value, the spring 11
Is configured so that the valve 12 is located on the right side of the discharge port 4a to form a flow path from the hollow portion 4b to the discharge port 4a.

Next, the operation of the above embodiment will be described.

When the movable contactor 4 is moved to the right by an operation mechanism (not shown) in the closed state of FIG. 1, the arc-extinguishing gas 1 in the puffer chamber 8 is compressed by the puffer device 5 in exactly the same manner as the above-mentioned conventional technique. It flows out from the air supply port 6a. Then, the arc-extinguishing gas 1 passes through the insulating nozzle 9 and is divided into a gas flow A toward the fixed contact 3 side and a gas flow B toward the hollow portion 4b of the movable contact 4.

At this time, when the breaking current is large, the gas flow B toward the hollow portion 4b of the movable contact 4 becomes extremely high due to the arc generated between the fixed contact 3 and the movable contact 4 as described above, The pressure becomes a certain value or more. As a result,
The valve 12 of the valve device 10 is pressed and the spring 11 contracts, the valve 10 moves to the right of the discharge port 4a, and a flow path from the hollow portion 4b of the movable contact 4 to the discharge port 4a is formed.

Therefore, the gas flow A toward the fixed contactor 3 side and the gas flow B toward the hollow portion 4b of the movable contactor 4 are formed, and the arc-extinguishing gas 1 is generated between the fixed contactor 3 and the movable contactor 4. Since it is blown onto the arc, it is well extinguished.

On the other hand, when the breaking current is a small current, the pressure of the gas flow B toward the hollow portion 4b of the movable contactor 4 is small and less than a certain value, so the valve 12 of the valve device 10 is discharged by the spring force of the spring 11.
Do not move to the right of 4a. Therefore, the hollow portion 4b remains in the closed state. As a result, since the arc-extinguishing gas 1 forms only the gas flow A toward the fixed contactor 3, the flow velocity of the gas flow A is not reduced and the fixed contactor 3 and the movable contactor 4 are not reduced.
It is satisfactorily extinguished by being blown to the arc generated between and.

Although the valve device 10 is composed of the spring 11 and the valve 12 in the above-mentioned embodiment, the valve 2 is cut in the central portion 13 as shown in FIG.
Alternatively, the valve device 20 may be configured by an elastic body having the above, and the valve device 20 may be disposed on the left side of the discharge port 4a. In this case as well, the gas flow B
When the pressure is less than a certain value, the notch 13 of the valve 22 is closed, and when the pressure is not less than the certain value, the notch 13 is opened. Therefore, the same operation and effect as in the above-described embodiment can be obtained.

[Advantage of Invention] As described above in detail with the embodiments, according to the present invention,
In the case of a large current interruption, both a gas flow toward the fixed contact side and in the hollow part of the movable contact are formed, and in the case of a small current interruption only the gas flow toward the fixed contact side is formed. Therefore, it is possible to obtain a puffer type gas circuit breaker capable of handling a large current cutoff and a small current cutoff.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is a cross-sectional view of a closed state, FIG. 2 is a cross-sectional view of a state during a large current interruption, and FIG. 3 is a small current interruption. Sectional view of the state of No. 4,
4A and 4B are a front view and a side sectional view of a valve device showing another embodiment, and FIG. 5 is a sectional view showing a conventional technique. In the figure, 1 is an arc-extinguishing gas 2 is a container 3 is a fixed contact 4 is a movable contact 4a is a discharge port 4b is a hollow part 5 is a puffer device 6 is a cylinder 7 is a piston 9 is an insulating nozzle 10, 20 is a valve device is there.

Claims (3)

[Scope of utility model registration request] 1. A container filled with a single-pressure arc-extinguishing gas, a movable contact having a fixed contact that can be opened and a hollow portion having a discharge port, and a piston and a cylinder. It is equipped with a puffer device that interlocks with the contactor to compress the arc-extinguishing gas, and an insulating nozzle that guides the arc-extinguishing gas from the puffer device and surrounds the movable contact, and is sprayed from the puffer device. An arc-extinguishing gas is formed in an arc generated between the movable contact and the fixed contact by forming a gas flow toward the fixed contact and a gas flow toward the hollow portion of the movable contact. In the case of spraying, provided in the hollow portion of the movable contactor is a valve device that closes the hollow portion when the pressure of the gas flow toward the hollow portion is less than a certain value, and opens when the pressure is a certain value or more. Characterized by File type gas circuit breaker. 2. A utility model registration claim characterized in that the valve device comprises a valve movable in the hollow portion across the discharge port and a spring having the valve locked at one end and fixed at the other end. A puffer type gas circuit breaker according to claim 1. 3. The puffer according to claim 1, wherein the valve device is made of an elastic body which is arranged closer to the movable contact than the discharge port and has a notch in the central portion. Shaped gas circuit breaker.