JPH0568044U - Gas circuit breaker - Google Patents

Abstract

(57) [Summary] [Structure] In a gas circuit breaker that combines the self-extinguishing action utilizing the expansion of gas in the boost chamber due to arc energy and the arc rotation extinguishing action due to the magnetic field generated by the coil, The outer wall of is used as a piston and a cylinder is provided on the side of the movable contact, thereby adding an arc extinguishing action by the suction puffer. [Effect] Self-extinguishing, arc rotation, suction puffer 3
By utilizing two arc-extinguishing functions, stable breaking performance from large current to small current can be obtained. Further, since the suction puffer is used only in the small current region, the suction puffer may have a small capacity, and even if the suction puffer is added, the increase in energy for driving the circuit breaker slightly increases. It can only be done.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a gas circuit breaker, and more particularly to a technique for improving arc extinguishing performance of a gas circuit breaker.

[0002]

[Prior Art]

 As arc extinguishing technology for gas circuit breakers, arc rotating type self-extinguishing gas circuit breakers and suction puffer self-extinguishing type gas circuit breakers have been conventionally known. These will be described with reference to FIGS. 2 and 3.

FIG. 2 is a sectional view of an arc rotating type self-extinguishing type gas circuit breaker. When the gas circuit breaker is in the conducting state, the fixed contact 2 and the movable contact 4 are in contact with each other, as shown in the figure.

At the time of interruption, the movable contactor 4 moves downward in the drawing by an operating mechanism (not shown). When the movable contactor 4 and the fixed contactor 2 are separated from each other, the current is commutated from the fixed contactor 2 and transferred to the runner 6 through the coil 5, and an arc is generated between the runner 6 and the movable contactor 4. Occur. Then, the arc is rotationally driven at high speed around the shaft 12 by the magnetic field generated by the current flowing through the coil 5. The rotation of the arc relatively blows gas onto the arc, and the arc rotation extinguishing action is performed by the cooling effect of the arc.

Further, inside the booster chamber 1, the nozzle 3 is closed by a movable contactor 4 and sealed. The gas pressure inside the booster chamber 1 rises as the arc rotates inside the sealed booster chamber 1. After that, when the movable contactor 4 moves further downward and exits from the pressure-increasing chamber 1, the high-pressure gas is ejected to the outside through the nozzle 3 formed at the tip of the outer wall 13 of the pressure-increasing chamber. The self-extinguishing function of extinguishing the arc between the movable contactor 4 and the movable contactor 4 is performed. In addition, 15 and 16 are fixed electrodes.

FIG. 3 shows a suction puffer type self-extinguishing type gas circuit breaker. The figure shows the energized state. In the energized state, the fixed contact 4 and the movable contact 2 are in contact with each other.

At the time of interruption, the movable contactor 4 moves downward in the figure by an operating mechanism (not shown). When the movable contactor 4 and the fixed contactor 2 are separated from each other, an arc is generated between the contactors, and the arc increases the gas pressure inside the pressure-increasing chamber 1. On the other hand, due to the downward movement of the movable contactor 4, the outer circumference of the suction piston 7 provided integrally with the movable contactor 4 comes into contact with the inner circumference of the suction cylinder 8 provided in the outer shell container 9, and the suction pack Acting as a fan, the gas pressure in the outer shell container 9 is lowered. When the movable contact 4 further moves downward and the tip of the movable contact 4 is disengaged from the nozzle 3, the high pressure gas pressure in the pressurizing chamber 1 is ejected through the nozzle 3 into the low pressure outer shell container 9. The high-pressure gas passes between the nozzle 3 and the movable contact 4 at high speed, and extinguishes an arc between the fixed contact 2 and the movable contact 4.

[0008]

[Problems to be solved by the device]

 Among the above two conventional examples, in the arc rotating type self-extinguishing type gas circuit breaker of FIG. 2, extinguishing is mainly performed by self-extinguishing for large current, and for medium current, The arc is mainly extinguished by arc rotation. On the other hand, when the small current is cut off, the effect of boosting the gas in the booster chamber cannot be fully obtained, and therefore arc extinguishing by self-extinguishing is insufficient. Further, the magnetic field generated by the current flowing through the coil 5 is also weak, and the arc extinction for small current due to arc rotation becomes insufficient. Therefore, it is difficult for this arc-rotating self-extinguishing type gas circuit breaker to obtain sufficient arc extinguishing performance when breaking a small current.

Further, in the suction puffer type self-extinguishing gas circuit breaker of FIG. 3, the large current is interrupted mainly by self-extinguishing. In the region of medium current or less, the effect of boosting the gas in the booster chamber by using the arc energy is insufficient, so arc is mainly extinguished by the suction puffer. For this reason, the suction puffer must be quite large in order to extinguish an arc at a medium current or less. Along with this, a large amount of operating energy is required to drive the suction puffer. This has a negative effect on the fact that the operating force, which is a feature of the self-extinguishing type gas circuit breaker, is reduced.

An object of the present invention is to obtain a stable arc extinguishing performance from a large current to a small current by efficiently utilizing the arc extinguishing function of self-extinguishing arc, rotary arc and suction puffer. Still another object of the present invention is to reduce the operating force at the time of shutting off and to simplify the structure of the piston / cylinder of the suction puffer.

The above and other objects and novel characteristics of the present invention will be apparent from the following description of the present specification and the accompanying drawings.

[0012]

[Means for Solving the Problems]

 The outline of the present invention is that in an arc rotary self-extinguishing type gas circuit breaker, the outer wall of the pressurizing chamber is used as a piston, and a suction puffer is formed together with a cylinder provided on the movable contact side.

[0013]

[Action]

 According to the above means, the extinction of large current and medium current is performed by self-extinguishing and arc rotation, and the extinction of small current is performed by the suction puffer. The fact that the small current is extinguished by this suction buffer does not simply extend the current cutoff range by adding a conventionally known suction buffer, but the suction puffer extinguishes the small current. Since only a small amount of puffer action needs to be loaded, the structure can be smaller than a normal suction puffer. As a result, the increase in the operating force of the circuit breaker will be small.

Hereinafter, the configuration of the present invention will be described together with an embodiment.

[0015]

【Example】

 FIG. 1 shows a cross section of one embodiment of the present invention. In the figure, 1 is a pressure raising chamber, 2 is a fixed contactor, 3 is a nozzle, 4 is a movable contactor, 5 is a coil, and 6 is a runner. These are arc extinguishing functions by arc rotation described so far. And self-extinguishing.

In the present example, a part of the outer circumference of the outer wall 13 of the pressurizing chamber 1 forms the piston 7. Further, a cylinder 8 is formed integrally with the movable contactor 4. When the movable contact 4 moves downward, the outer circumference of the piston 7 and the inner circumference of the cylinder 8 come into contact with each other, and when the movable contact 4 further moves downward, the piston 7 and the cylinder 8 contact the outer circumference of the piston 7. The gas pressure in the space formed by the inner circumference of the linder 8 is reduced to form a suction puffer.

Further, in this example, the suction cylinder 8 is provided with an opening 17, and the opening 17 is closed by a check valve 10 urged by a spring 11. The check valve 10 is configured to release the internal pressure to the outside of the cylinder 8 when the pressure inside the suction puffer increases.

Further, in the present example, the cylinder 8 is made of the same material as the movable contactor 4, and contacts with the fixed contactor 14 so that a part of the energizing current can flow as the movable contactor. Function.

Next, the operation of this example will be described.

In the energized state shown, the fixed contacts 2 and 14 contact the movable contact 4 and the suction cylinder 8 to energize them.

At the time of interruption, the movable contactor 4 moves downward in the figure by an operation mechanism (not shown). When the movable contactor 4 separates from the fixed contactor 2, the electric current commutates from the fixed contactor 2 and moves to the runner 6 through the coil 5, and an arc is generated between the runner 6 and the movable contactor 4. To do. Then, the arc is rotationally driven at high speed around the shaft 12 by the magnetic field generated by the current flowing through the coil 5. The rotation of the arc inside the booster chamber 1 raises the gas pressure inside the booster chamber 1. In addition, the rotation of the arc relatively blows gas onto the arc to extinguish the arc due to the cooling effect of the arc.

On the other hand, when the movable contact 4 is moved downward, the inner periphery of the cylinder 8 provided integrally with the movable contact 4 comes into contact with the outer periphery of the piston 7 formed on the outer wall 13 of the pressure raising chamber, and suction is performed. It operates as a puffer to reduce the gas pressure in the space surrounded by the piston 7 and the cylinder 8. After that, when the movable contactor 4 moves further downward and escapes to the outside of the pressure-increasing chamber 1, the gas is passed through the nozzle 3 formed at the tip of the outer wall 13 of the pressure-increasing chamber into the space surrounded by the piston 7 and the cylinder 8. Flows out, and an arc extinguishing action is performed to blow out the arc between the runner 6 and the movable contactor 4.

In the present example, when the breaking current is a large current or a medium current, the arc is extinguished by self-extinguishing and the arc rotation as in the conventional case. That is, when the breaking current is a large current, the gas boosting effect inside the booster chamber 1 is sufficiently obtained, and the self-extinguishing action of blowing this gas to the arc is performed. In the medium current range, the gas is boosted by the arc energy, and the arc rotation by the coil adds the cooling effect of the arc to interrupt the current.

At the time of shutting off the large current and the medium current, the high-pressure gas discharged from the pressurizing chamber 1 is jetted into the space formed by the cylinder 8 and the piston 7 of the suction puffer. When the pressure in this space becomes high, the check valve 10 opens, so that the ejection of high-pressure gas is not hindered. Therefore, the addition of the suction puffer does not reduce the ability to extinguish large or medium currents.

Next, when the breaking current is a small current, the self-extinguishing action by boosting the gas and the extinguishing action by arc rotation become insufficient. When the breaking current is a small current, the gas pressure in the space formed by the cylinder 8 and the piston 7 decreases due to the piston 7 and the cylinder 8, and the gas in the pressurizing chamber 1 is sucked into the space through the nozzle 3. At the time of arcing, the arc is extinguished by the suction puffer by blowing gas against the arc. During this operation, the check valve 10 closes the opening 17 of the cylinder 8 with the spring 11, so that the suction action is reliably performed.

Since this suction puffer only needs to extinguish a small current, its puffer action may be small, and the suction puffer may have a small capacity. As a result, the increase in operating force due to the addition of the suction puffer can be reduced.

Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the above-mentioned embodiments and can be variously modified without departing from the scope of the invention. Nor.

[0028]

[Effect of the device]

 The present invention efficiently utilizes the three arc extinguishing functions of self-extinguishing arc, arc rotation, and suction puffer to obtain stable breaking performance from large current to small current.

Further, since the suction puffer is used only in the small current region, the suction puffer may have a small capacity, and even if the suction puffer is added, the energy for driving the circuit breaker is not increased. The increase will be a small increase.

Since the piston of the suction puffer is formed by using the outer wall of the pressurizing chamber, the structure of the suction puffer is simple and small.

Furthermore, by utilizing the cylinder of the suction puffer as the movable contactor, it is possible to increase the current carrying capacity without increasing the size of the device.

Further, by providing a check valve in the cylinder of the suction puffer, it is possible to surely perform the suction puffer action and prevent obstruction of the gas flow at the time of interrupting a large current and a medium current. Is.

[Brief description of drawings]

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

FIG. 2 is a sectional view of a conventional arc rotary type self-extinguishing type gas circuit breaker.

FIG. 3 is a cross-sectional view of a conventional suction puffer type self-extinguishing type gas circuit breaker.

[Explanation of symbols]

1 ... Pressure rising chamber, 2 ... Fixed contact, 3 ... Nozzle, 4 ... Movable contact, 5 ... Coil, 6 ... Runner, 7 ... Piston, 8 ...
Cylinder, 9 ... Outer shell container, 10 ... Check valve, 11 ... Spring, 12 ... Central shaft, 13 ... Pressure chamber outer wall, 14 ... Fixed contact.

Claims (3)

[Scope of utility model registration request] 1. A fixed contact, a coil and a runner are provided inside the boost chamber, and the arc is rotated by a self-extinguishing action utilizing expansion of gas inside the boost chamber by arc energy and a magnetic field generated by the coil. In a gas circuit breaker that also uses an arc rotation extinguishing action to be driven, a piston is provided on the outer wall of the booster chamber, and a cylinder is provided on the movable contact side so that a suction puffer is formed by the piston and the cylinder. Characteristic gas circuit breaker. 2. The gas circuit breaker according to claim 1, wherein the cylinder is provided with a check valve. 3. The gas circuit breaker according to claim 1, wherein the cylinder is made of a conductive material to form a movable contactor, and a fixed contactor is provided on the fixed side for contacting the movable contactor.