JPH0520235U - Gas circuit breaker - Google Patents

Abstract

(57) [Summary] [Purpose] To enhance the rotational driving force of the arc and improve the breaking performance in the small and medium current range. [Structure] An annular fixed contactor 5 and a vertically movable pipe-shaped movable contactor 10 which comes into contact with and separates from the fixed contactor 5 are arranged in an upper portion and a lower portion in a shutoff portion outer cylinder 1 in which an insulating gas is filled,
An annular drive coil 7 is arranged outside the fixed contact 5, and an annular arc runner 8 connected to the fixed contact 5 via the coil 7 is provided below the drive coil 7, and the movable contact is also provided. An auxiliary coil 11 for generating a magnetic field in the same direction as the magnetic field of the drive coil 7 between the arc runner 8 and the movable contact 10 when an arc is generated is formed at the upper end of 10.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a gas circuit breaker for extinguishing an arc generated by the separation of a fixed contact and a movable contact from each other by rotating and driving the arc by a magnetic field.

[0002]

[Prior Art]

Conventionally, the arc rotary type gas circuit breaker is configured as shown in FIG. 4 when the self-expansion effect is also used. That is, the insulating partition plate 2 is disposed in the shut-off portion outer cylinder 1 in which an insulating gas such as SF ₆ gas is sealed to form the booster chamber 3, and the connecting conductor 4 is provided above the booster chamber 3. The conductive support tube 6 is fixed by bolts, and the fixed contactor 5 made of a tulip-shaped contactor is supported and connected to the connection conductor 4 and fixed to the outside of the tip of the fixed contactor 5 simultaneously with the connection conductor 4. A ring-shaped drive coil 7 is disposed through the above, and a ring-shaped arc runner 8 made of a copper plate or the like is attached to the inner peripheral surface and the lower surface thereof.

Further, a hemispherical nozzle portion 9 projecting upward is integrally formed in a central portion of the partition plate 2, and a pipe-shaped movable contact 10 is vertically moved in an opening transparently provided in the central portion. The fixed contact 5 is contacted with and separated from the fixed contact 5. It should be noted that one end of the drive coil 7 is connected to the fixed contact 5 via the support cylinder 6 and the connecting conductor 4, and the other end is connected to the arc runner 8. Then, 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 5, the movable contact 10 is separated from the fixed contact 5, and an arc is generated between the two contactors 5, 1. Occurs.

In a large current region, the heat of this arc heats and decomposes the insulating gas in the arc space to form hot gas, which increases in pressure, and along with this, the hot gas spreads in the outer peripheral direction, Due to the gas flow due to this diffusion, a high-density insulating gas (cold gas) in the pressurizing chamber 3 is pushed into the outer peripheral portion to accumulate pressure.

After that, when the arc current starts to decrease toward the current zero point, the generated pressure force in the arc space decreases, so that the hot gas is discharged through the inside of the movable contact 10 and the pressure chamber is increased. The cold gas pushed into the outer periphery of 3 is pushed back into the arc space, and this gas is guided to the arc space and blown to the arc near the current zero point, and the arc is extinguished.

On the other hand, in the medium and small current region, a large pressure accumulating effect due to the arc energy cannot be expected, but the arc generated by the separation of both the contactors 5, 10 moves from the fixed contactor 5 as the movable contactor 10 moves. In order to shift the arcing point to the arc runner 8, an arc current is introduced to the coil 7, and a magnetic field generated by the coil 7 is generated between the arc runner 8 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, the arc rotates at high speed on the arc runner 8 in the atmosphere of the insulating gas, and the arc is rapidly cooled and extinguished. To arc.

Even in the large current region, a part of the arc generated at the time of opening is transferred from the fixed contact 5 to the arc runner 8 and the arc is driven to rotate by the magnetic field generated by the coil 7. Heating and decomposition are promoted and the pressure accumulation effect is enhanced.

[0009]

[Problems to be solved by the device]

 In the conventional gas circuit breaker described above, the arc generated by the separation of the contacts 5 and 10 is transferred to the arc runner 8 to drive the drive coil 7 to rotate and extinguish the arc by its magnetic field. However, there is no magnetic field until the arc moves to the arc runner 8, and there is no extinction ability, so there is a drawback that the arc time becomes long.

Further, even after the arc moves to the arc runner 8, the magnetic field is weak at the position away from the arc runner 8, that is, the movable contact 10 side, and the arc foot on the movable contact 10 side hardly rotates. The arc cooling effect in this portion cannot be expected so much, and in addition, there is a drawback that the movable contact 10 is greatly damaged.

The present invention has been made in view of the above problems of the conventional technology. The purpose of the present invention is to strengthen the magnetic field on the movable contact side to increase the arc rotation force. It is to provide a gas circuit breaker that can be turned on.

[0012]

[Means for Solving the Problems]

 In order to achieve the above object, in the gas circuit breaker of the present invention, an annular fixed contact is provided in an upper part and a lower part in an outer cylinder of a breaking part in which an insulating gas is sealed, and vertically movable so as to be connected to and separated from the fixed contact. The pipe-shaped movable contact is placed, the annular drive coil is placed outside the fixed contact, and the annular arc runner connected to the fixed contact via this coil is provided under the drive coil. In addition, an auxiliary coil is formed at the upper end of the movable contactor to generate a magnetic field in the same direction as the magnetic field of the drive coil between the arc runner and the movable contactor when an arc occurs.

[0013]

[Action]

 In the gas circuit breaker configured as described above, when the movable contact is separated from the fixed contact at the time of interruption, an arc is generated between the fixed contact and the upper end of the movable contact at this time. An arc current flows through the auxiliary coil at the upper end, and a magnetic field is generated at the upper end of the movable contact at the same time as the opening, and the foot of the arc on the movable contact side is rotated.

After that, when the arc moves from the fixed contact to the arc runner, an arc current also flows in the drive coil, a magnetic field is generated by the drive coil, and a rotating force acts on the entire arc. The direction of the magnetic field due to the drive coil and the direction of the magnetic field due to the drive coil are in the same direction between the arc runner and the movable contact, and the magnetic fields generated by both act on the arc. It rotates and completes extinguishing in a short time.

[0015]

【Example】

 Examples will be described with reference to FIGS. 1 to 3. In these drawings, the same reference numerals as those used above indicate the same or corresponding ones, and the difference from the prior art is that the auxiliary coil 11 is integrally formed at the upper end of the pipe-shaped movable contact 10. That is, as shown in FIG. 2, two horizontal cuts 11a from the left side and two horizontal cuts 11b from the right side are formed alternately at the upper end of the movable contactor 10. Two vertical cuts 11c from the front and two vertical cuts 11d from the back are alternately formed between the cuts 11a and 11b, and an auxiliary coil 11 having 2 to 3 turns is formed in series on the movable contact 10. It is a thing.

In this case, the winding direction of the auxiliary coil 11 is set so that the direction of the magnetic field generated when a current flows through the auxiliary coil 11 is the same between the arc runner 8 and the movable contact 10 with respect to the direction of the magnetic field generated by the drive coil. Has been done. At the time of closing, the peripheral surface of the movable contactor 10 immediately below the auxiliary coil 11 comes into contact with the fixed contactor 5, and the auxiliary coil 11 is not driven.

In such a configuration, when the movable contact 10 is moved downward from the closed state and separated from the fixed contact 5, an arc is generated between both contacts 5 and 10 via the auxiliary coil 11. It is generated, an arc current flows through the auxiliary coil 11, a magnetic field is generated by the auxiliary coil 11, and the legs of the arc on the movable contact 10 side rotate on the upper surface of the auxiliary coil 11 by the electromagnetic force of this magnetic field.

After that, when the arc moves from the fixed contact 5 to the arc runner 8 in accordance with the downward movement of the movable contact 10, the arc current is also introduced to the drive coil 7, and the magnetic field generated by the drive coil 7 becomes the arc. At this time, as shown in FIG. 3, the combined (addition) magnetic field of the magnetic field of the drive coil 7 and the magnetic field of the auxiliary coil 11 acts on the arc between the arc runner 8 and the auxiliary coil 11, so that the arc is strong. Rotational force works, the arc rotates at high speed, and is instantly cooled and extinguished.

In the above-described embodiment, the auxiliary coil 11 is formed only by the cuts 11a to 11d from the four sides for easy processing, but the horizontal cut position may be changed or the spiral cuts may be formed. By forming the, it is possible to obtain an auxiliary coil capable of generating a more effective magnetic field.

[0020]

[Effect of the device]

 Since the present invention is configured as described above, it has the following effects. An auxiliary coil is formed on the upper end of the pipe-shaped movable contactor, and when an arc is generated, a magnetic field is generated between the arc runner and the movable contactor in the same direction as the direction of the magnetic field by the drive coil. The generated arc can be rotationally driven by a strong synthetic magnetic field generated by both coils, increasing the arc's rotating force and extinguishing ability, and it is possible to move the arc that was only rotating on the conventional arc runner. Since the contact side can also be rotationally driven, the cooling effect of the arc is significantly improved, and the breaking performance in the small and medium current range that depends on the arc rotating effect is improved and stabilized.

Moreover, since the magnetic field generated by the auxiliary coil is generated at the same time as the arc is generated, the arc time can be shortened as compared with the conventional case, and the arc can be rotated at a high speed even on the movable contact side, so that the wear of the movable contact is reduced. A significant reduction effect is obtained. Furthermore, since a magnetic field can be generated on both the fixed contact side and the movable contact side to extinguish the arc, the structure is more advantageous in terms of insulation performance than the conventional structure, and the one with the same size as the conventional one has a higher rated voltage. It can be applied to.

[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 perspective view of an auxiliary coil of the embodiment.

FIG. 3 is an explanatory diagram of a magnetic field generated in the example.

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

 1 Blocking Part Outer Cylinder 5 Fixed Contact 7 Drive Coil 8 Arc Lanna 10 Movable Contact 11 Auxiliary Coil

Claims (1)

[Scope of utility model registration request] 1. An annular fixed contactor and a vertically movable pipe-shaped movable contactor which is brought into contact with and separated from the fixed contactor are provided in an upper portion and a lower portion of an outer cylinder of a shutoff portion in which an insulating gas is filled. A gas circuit breaker, wherein an annular drive coil is arranged outside the fixed contact, and an annular arc runner connected to the fixed contact via the coil is provided under the drive coil. A gas circuit breaker in which an auxiliary coil is formed at the upper end of the movable contactor and the direction of the magnetic field by the auxiliary coil and the direction of the magnetic field by the drive coil are the same between the arc runner and the movable contactor when an arc occurs. ..