JPH0575935U - Gas circuit breaker - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a gas circuit breaker that prevents the arc from spreading in the outer peripheral direction during arc rotation and has improved breaking performance. [Structure] An annular fixed contactor 4 is provided in a pressure-increasing chamber 2 in which an insulating gas is filled, an annular drive coil 6 is provided outside the fixed contactor 4, and a cylindrical shape is provided inside the drive coil 6. -Shaped arc runner 7 is attached integrally, and fixed contactor 4
The movable contactor 1 whose upper end contacts and separates from the fixed contactor 4 below
0 is provided so as to be movable up and down, and an annular insulating nozzle 9 is integrally attached to the lower end portion of the arc runner 7, which is disposed in the lower portion of the pressure boosting chamber 2 and through which the movable contact 10 is detachably inserted.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a self-expanding gas circuit breaker.

[0002]

[Prior Art]

 Conventionally, a gas circuit breaker utilizing the self-expansion effect is configured as shown in FIG. 2, for example. That is, a booster chamber 2 is formed inside a cylindrical conductive terminal block 1 having a lid and having an upper terminal, and a tulip-shaped fixed contact is provided in the booster chamber 2 via a contact table 3 fixed to the terminal block 1. The child 4 is disposed, and an annular drive coil 6 is provided outside the lower portion of the fixed contactor 4 via a cylindrical conductor 5 fixed to the contactor stand 3, and the inner circumference and the lower surface of the drive coil 6 are provided. An annular arc runner 7 is integrally provided. One end of the drive coil 6 is electrically connected to the fixed contact 4 via the tubular conductor 5 and the contact base 3, and the other end is connected to the arc runner 7.

Further, a supporting cylinder 8 is fixed to the outer peripheral portion of the lower end of the terminal block 1, an insulating nozzle 9 is attached to the inside of the supporting cylinder 8, and the supporting cylinder 8 is inserted below the fixed contact 4 inside the nozzle 9 so as to be freely inserted and removed. A movable contact 10 in the form of a pipe that comes in contact with and separates from the fixed contact 4 is provided so as to be movable up and down.

It should be noted that the contact base 3 has a vertical gas flow hole 11 whose lower end opens inside the fixed contact 4, and a cross-shaped communication hole 1 whose upper end opens to the outer periphery of the contact base 3. 2 is formed. In addition, the above-mentioned structure is housed in a circuit breaker pole that is filled with an insulating gas such as SF ₆ gas.

Then, when the movable contact 10 is moved downward from the throwing state in which the movable contact 10 is in contact with the fixed contact 4 as shown by the broken line in FIG. 2, the movable contact 10 is opened from the fixed contact 4. An arc is generated between the contactors 4 and 10 when separated.

In a large current region, the heat of this arc heats and decomposes the insulating gas in the arc space to form hot gas, and the pressure rises. As shown by the arrow, the high-density insulating gas in the booster chamber 2, that is, cold gas, diffuses upward and in the outer peripheral direction and is pushed into the booster space outside the nozzle 9 to accumulate pressure.

After that, when the movable contact 10 comes out of the tip of the nozzle 9, the accumulated gas in the boosting space is blown to the arc space as shown by the solid arrow in the figure, and the gas is blown to the arc. It cools and extinguishes.

On the other hand, in the medium and small current regions, the large boosting effect as described above cannot be expected, but the arc generated by the separation of the contacts 4 and 10 is generated as the movable contact 10 moves. Since the arc point is transferred from the fixed contactor 4 to the arc runner 7, an arc current is introduced to the coil 6, and a magnetic field is generated between the arc runner 7 and the movable contact 10.

Therefore, an electromagnetic force, that is, a rotating force according to Fleming's left-hand rule, acts on the arc, and the arc rotates at high speed around the lower end of the hollow portion of the arc runner 7 in the insulating gas atmosphere, and the arc rapidly moves. It cools and extinguishes. Even in the above-mentioned large current region, a part of the arc is transferred to the arc runner 7, so that the arc is rotated to accelerate the heating and decomposition of the insulating gas and enhance the self-expansion effect.

[0010]

[Problems to be solved by the device]

 However, in the above-described conventional gas circuit breaker, when the arc generated when the contacts 3 and 10 are separated is transferred to the arc runner 7 and rotated by the coil magnetic field, the arc runner 7 has a structure due to the structure of the arc runner 7. The legs of the upper arc tend to spread from the inner peripheral portion to the outer peripheral portion as they rotate, and in particular the thermal expansion effect of the hot gas by the arc tends to promote the spread of the arc in the outer peripheral direction.

Therefore, as a result of the arc spreading to the outer peripheral portion where the magnetic field is weak and the orthogonal component of the magnetic flux with respect to the arc is small, the arc does not rotate at high speed, the arc time is long, and the breaking performance deteriorates.

The present invention has been made in view of such problems of the conventional technique, and the purpose thereof is to reliably prevent the arc from spreading in the outer peripheral direction and to improve the breaking performance. It is to provide a gas circuit breaker that can be improved.

[0013]

[Means for Solving the Problems]

 In order to achieve the above object, in the gas circuit breaker of the present invention, an annular fixed contactor disposed in a booster chamber containing an insulating gas, and an annular magnetic field generator provided outside the annular fixed contactor. An arc runner integrated with the magnetic field generator, a movable contactor that is vertically movable below the fixed contactor and has an upper end part that contacts and separates from the fixed contactor, and is installed in the lower part of the booster chamber. It is equipped with an annular insulating nozzle with a movable contact inserted through it inside and out, and the arc runner is cylindrically arranged and placed inside the magnetic field generator.The nozzle is integrated with the lower end of the arc runner. It is attached to.

[0014]

[Action]

 According to the above configuration, since the arc runner is cylindrical and the nozzle is integrally attached to this lower end, the arc generated when the movable contact inserted inside the nozzle and the fixed contact are separated from each other Even after the transition, this arc can be confined in the inner circumference of the arc runner, and the arc rotates at high speed on the inner circumference surface of the arc runner under the influence of the magnetic field generated by the magnetic field generator.

Moreover, since the arc runner and the nozzle are integrated, the pressure inside the arc runner is rapidly increased, and the pressure becomes extremely high. The spraying effect is enhanced.

[0016]

【Example】

 An example will be described with reference to FIG. Note that the same reference numerals as those used in the related art indicate the same or corresponding ones. A tulip-shaped fixed contactor 4 connected to the terminal block 1 via a contactor base 3 is provided in a pressure-increasing chamber 2 formed inside a conductive terminal block 1, and a tubular shape is provided outside the fixed contactor 4. An annular drive coil 6 supported by the contactor base 3 via a conductor 5 is provided, and a cylindrical arc runner 7 is integrally provided inside the drive coil 6 and insulated at the lower end of the arc runner 7. The sex nozzle 9 is integrally attached by screwing or the like.

A flange portion that closes the lower end of the booster chamber 2 is integrally formed on the outer periphery of the upper portion of the nozzle 9, whereby a booster space is formed in the outer peripheral portion of the booster chamber 2, and the booster space is gas-circulated in the arc space. The holes 11 and the communication holes 12 communicate with each other.

In the gas circuit breaker having such a configuration, when the movable contact 10 is moved downward from the closed state in which the movable contact 10 is in contact with the fixed contact 4 as shown by the broken line in FIG. At the same time when the contact 10 is separated from the fixed contact 4, an arc is generated between the contacts 4 and 10.

In the large current region, the hot gas diffuses in the outer peripheral direction and upward as the pressure in the arc space increases due to the arc. In this case, since the arc runner 7 and the nozzle 9 are integrated, The internal pressure is much higher than before.

After that, when the movable contact 10 comes out of the small diameter portion of the nozzle 9, the pressure gas inside the arc runner 7 and the nozzle 9 is blown onto the movable contact 10, and further, in the pressure rising space outside the coil 6. Cold gas is also blown into the arc space through both holes 12 and 11, and the arc is extinguished.

On the other hand, in the medium and small current region, the arc moves from the fixed contact 4 to the arc runner 7 as the movable contact 10 moves downward, and the inner peripheral surface of the arc runner 7 is moved by the coil magnetic field generated by the excitation of the coil 6. Rotate. In this case, since the arc is confined inside this by the arc runner 7 and the nozzle 9, the arc does not spread in the outer peripheral direction, and the arc is rotated at a high speed under the strong magnetic field of the coil 6 and extinguished. ..

Further, even in this small and medium current region, the pressure inside the arc runner 7 and the nozzle 9 becomes sufficiently high, so that the effect of blowing gas to the arc is obtained, and the arc is extinguished quickly.

By thus forming the arc runner 7 in a cylindrical shape and attaching the nozzle 9 integrally to the lower end of the arc runner 7, it is possible to prevent the spread of the arc when the arc is rotated, and also to make a large self-expansion. The effect can be expected and the cutoff performance is dramatically improved. In addition, the nozzle 9 can be attached very easily as compared with the conventional one in which the support cylinder is used.

[0024]

[Effect of the device]

 Since the present invention is configured as described above, it has the following effects. A cylindrical arc runner is integrally provided on the inner circumference of the annular magnetic field generator provided outside the fixed contact, and an annular insulating nozzle through which the movable contact is detachably inserted is integrally provided at the lower end of this arc runner. Since the arc generated when mounting and separating both contacts is confined inside the arc runner and nozzle, it is possible to prevent the arc from spreading to the outside during arc rotation and at the same time enhance the self-expansion effect of the arc. Therefore, it is possible to improve the shutoff performance. Moreover, it is not necessary to use a separate component for mounting the nozzle, and the nozzle can be easily mounted.

[Brief description of drawings]

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

FIG. 2 is a cross-sectional view showing a conventional gas circuit breaker.

[Explanation of symbols]

 2 Booster chamber 4 Fixed contact 6 Drive coil 7 Arc runner 9 Insulating nozzle 10 Moving contact

Claims (1)

[Scope of utility model registration request] 1. An annular fixed contact arranged in a pressure-increasing chamber filled with an insulating gas, an annular magnetic field generator provided outside the fixed contact, and integrally provided in the magnetic field generator. Arc runner, a movable contactor that is vertically movable below the fixed contactor and has an upper end portion that comes into contact with and separates from the fixed contactor, and the movable contactor that is disposed in the lower portion of the booster chamber is provided inside. In a gas circuit breaker comprising an annular insulating nozzle that is inserted and removed freely, the arc runner is formed into a cylindrical shape and is arranged on the inner circumference of the magnetic field generator, and the nozzle is integrated with the lower end of the arc runner. A gas circuit breaker characterized by being attached to.