JPH0449211B2 - - Google Patents

Description

Detailed Description of the Invention [Problems of Background Art] (Field of Industrial Application) The present invention relates to a circuit breaker in which the connection structure of bushing conductors on the fixed side of the circuit breaker is improved.

(Prior Art) In recent years, the trend of increasing power demand and concentration of power consumption in cities has become stronger year by year. Moreover, the supply of electric power corresponding to such demand is required to be highly reliable and economical, and power transmission systems are becoming more complex and larger in capacity. On the other hand, due to the shortage of land for substations in cities, there is a need to downsize substations, and closed gas switchyards, in which disconnectors, busbars, etc. are insulated with SF ₆ gas, are becoming popular. In a closed gas switchyard, the reliability of circuit breakers, which are important equipment in the switchyard, is required.
There is a need for miniaturization. Furthermore, it is desired to shorten the recovery time in the event of an accident and shorten the power outage time during periodic inspections.

An example of a conventional circuit breaker used in such a closed gas switchyard is shown in FIG. That is,
The main interrupting part of the circuit breaker is housed in a tank 1 filled with an insulating arc-extinguishing gas such as SF ₆ gas. This main interrupting section is composed of a fixed side contact section 2 and a movable side contact section 3, and the fixed side contact section 2 and the movable side contact section 3 are arranged opposite to each other with an insulating cylinder 4 in between. . This insulating tube 4 is made of an organic compound such as epoxy resin, and has inferior strength compared to metal, so it is screwed into the fixed side support flange 5 and the movable side support flange 6, and is attached to these support flanges. It is connected to the fixed side contact part 2 and the movable side contact part 3 via 5 and 6.

The fixed side contact part 2 includes a fixed arc electrode 7 provided at the center, a fixed main current-carrying contact 8 provided on the outer periphery of this fixed arc electrode 7, and further, their base ends supported by a fixed electrode support 9. It is configured,
This fixed electrode support 9 is detachably connected to the fixed side support flange 5. A bushing conductor 12 housed in the center of the insulator tube 11 is connected to the base end of the fixed electrode support 9 via a connecting conductor 10 . This bushing conductor 12 is supported by an upper flange 13 of the insulator pipe 11, and an overhead wire (not shown) is connected to this upper flange 13. In addition,
The current path of this circuit breaker is from the bushing conductor 12 to the connection conductor 1 from the overhead wire connected to the upper flange 13 insulated from the tank 1 by the insulator pipe 11.
0 to the fixed side contact portion 2.

On the other hand, the movable side connecting portion 3 has a puffer cylinder 15 connected to a drive mechanism (not shown) via an operating rod 14, and a puffer piston 16 fixed inside the puffer cylinder 15. A puffer chamber 17 is formed, and this puffer chamber 17 serves as a gas pressure chamber into which arc-extinguishing gas can enter and exit. Said puffer cylinder 1
At the center of the tip of 5, there is a movable arc electrode 18 that contacts the fixed arc electrode 7;
An insulating nozzle 19 and a movable current-carrying contact 20 are provided so as to surround it. Furthermore, a conductor energizing contact 25 is disposed on the outer periphery of the puffer cylinder 15 to establish electrical contact between the puffer cylinder 15 and a conductor connecting portion 22, which is housed in an insulator tube 23. It is connected to the external overhead wire via a central conductor that is not

Such a breaking operation of the circuit breaker is performed from the closed state of the movable side contact portion 3 and the fixed side contact portion 2 to the closed state of the movable side contact portion 3 and the fixed side contact portion 2.
moves to the right in the figure, and first, the fixed main current-carrying contact 8 and the movable main current-carrying contact 20 are separated, then the fixed arc electrode 7 and the movable arc electrode 18 are separated, and the circuit breaker is in the open state. Become. At this time, the puffer cylinder 15 also moves together with the movable contact portion 3, so
The SF ₆ gas in the puffer chamber 17, which is the space between the puffer piston 16 and the fixed puffer piston 16, is blown through the insulating nozzle 19 onto the arc generated between the fixed arc electrode 7 and the movable arc electrode 18. , the interruption is completed by the extinction of the arc.

(Problems to be Solved by the Invention) By the way, in the circuit breaker as described above, since high-temperature arcs are generated in the fixed arc electrode 4 and the movable arc electrode 18, measures such as using heat-resistant materials are not taken. ing. However, due to the high heat, the re-arc electrodes 7, 18 become fatigued and damaged. In addition, the fixed main current-carrying contact 8 and the movable main current-carrying contact 20 open before both arc electrodes 7 and 18, so although they are minute compared to both arc electrodes 7 and 18, they are still subject to wear and tear due to arcing. do. Therefore, it is necessary to regularly inspect these contacts and replace worn parts to maintain the breaking performance of the circuit breaker. There is a need to replace these contacts in as short a time as possible to minimize the time the circuit breaker is down.

By the way, when considering the replacement or inspection work of the fixed arc electrode 7 and the movable arc electrode 18, first, the connecting conductor 10 and the bushing conductor 1
2 from the fixed contact part 2, the fixed side contact part 2 having the fixed arc electrode 7 and the fixed main energizing contact 8 is taken out of the tank 1. After replacing or inspecting the fixed arc electrode 7 and the fixed main current-carrying contact 8, the fixed side contact part 2 is returned to the tank 1, and the connecting conductor 10 and the bushing conductor 12 are
will be installed. In this way, contact replacement or inspection work always involves the work of attaching and detaching the bushing conductor 12 from the fixed contact part 2, but since this bushing conductor 12 is fixed to the insulator pipe 11 via the upper flange 13, the bushing conductor 12 In order to pull it up, it is necessary to disconnect the upper flange 13 and the insulator tube 11. Since this insulator tube 11 is made of a material that is brittle against impacts, etc., the bushing conductor 1
If excessive force is applied to the bushing conductor 12, it may break, so the bushing conductor 12 needs to be attached and detached carefully. Moreover, the bushing conductor 12 is long and heavy, so handling it requires excessive effort and time. The long time it takes to attach and detach the bushing conductor 12 increases the time required to replace or inspect the contacts, which means that the power outage time becomes longer, and the longer the power outage time, the greater the social impact.

Furthermore, in a circuit breaker configured to attach and detach the bushing conductor 12 in this way, the connecting conductor 10 was required between the bushing conductor 12 and the main interrupting part.
This increased the number of parts, took time to assemble, and reduced reliability.

Furthermore, the hot gas heated by the heat generated by the arc contains metal vapor in which metal powder is dissolved due to wear between members during the interrupting operation, so that the dielectric strength of the circuit breaker generally decreases. especially,
The hot gas flows into the insulator tube 11 from behind the fixed side contact part 2.
If it flows inside, the dielectric strength inside the insulator tube 11 decreases,
The reliability of the circuit breaker decreased.

The present invention was proposed to solve the problems of conventional circuit breakers as described above, and its purpose is to shorten the time for inspecting or replacing contacts by improving the mounting position of the bushing conductor. The object of the present invention is to reduce the number of parts, eliminate the influence of hot gas, and provide a reliable circuit breaker.

[Structure of the Invention] (Means for Solving the Problems) The circuit breaker of the present invention has a bushing conductor connection portion formed on the fixed side support flange of the insulating tube, and a locking portion provided at the base end of the bushing conductor. , this bushing conductor is connected to the conductor connection portion of the fixed side support flange of the insulating tube.

Note that the conductor connection portion is preferably formed integrally with the fixed side support flange.

(Function) In the circuit breaker of the present invention, by connecting the bushing conductor to the bushing conductor connection part formed on the fixed side support flange, the bushing conductor can be removed from the bushing conductor connection part when inspecting or replacing the contacts of the main interrupting part. The fixed side contact part can be attached and detached to inspect or replace the contact without removing it.

(Example) Next, an example of the circuit breaker of the present invention will be described with reference to FIG.

Note that the same parts as those in the prior art are given the same reference numerals and the description thereof will be omitted.

*Configuration of Example* In FIG. 1, the bushing conductor 12 is connected to the fixed side support flange 5 of the insulating cylinder 4. That is, the conductor connection portion 31 of the bushing is integrally molded on the fixed side support flange 5. The conductor connection portion 31 is formed in a convex shape, and the protrusion direction is provided at the same angle as the mounting angle of the bushing conductor 12. That is, a taper perpendicular to the bushing conductor 12 is formed on the surface of the fixed side support flange 5, and the conductor connection portion 31 is provided perpendicularly thereto. On the other hand, the bushing conductor 12 is formed with a locking part 32 in which the base end or the entire bushing conductor 12 is hollow, and the inner peripheral surface of the locking part 32 conducts current between the outer peripheral surface of the conductor connection part 31. They are face-to-face fitted.

*Operation of the embodiment* In this embodiment configured as described above, the fixed side bushing conductor 12 is attached to the conductor connection part 31 provided on the fixed side support flange 5, so that the fixed arc electrode 7 and When replacing or inspecting the fixed main energizing contact 8, remove the fixed side contact part 2 having the fixed arc electrode 7 and the fixed main energizing contact 8 from the fixed side support flange 5, take it out of the tank 1, and remove the fixed arc electrode 7 and the fixed main energizing contact 8 from the tank 1. Inspect the electrode 7 and fixed main energizing contact 8 and replace if damaged.
The process is completed by attaching the fixed side contact portion 2 again. That is, for this work, the bushing conductor 15
This can be done with the bushing conductor 12 attached to the fixed side support flange 5, and the work of attaching and detaching the bushing conductor 12 is completely eliminated.

*Effects of the Example* In the circuit breaker of this example, there is no need to work on the bushing conductor 12 when replacing and inspecting the fixed arc electrode 7 and the fixed main current-carrying contact 8, so the time required for attaching and detaching the bushing conductor is reduced. This saves time and reduces work time. In addition, since the conductor connection portion 31 of the bushing conductor 12 is integrated with the fixed support flange 5, the number of parts can be reduced.
This reduces assembly time and improves reliability.
Furthermore, since the bushing conductor 12 is connected to the fixed side support flange 5 of the insulating tube 4, the exhaust port 40 of the hot gas caused by the arc is placed closer to the end of the tank than the attachment point of the insulator tube 11. Hot gas will no longer flow into the insulator tube 11, and there will be no fear that the dielectric strength within the insulator tube 11 will decrease, thereby improving reliability.

Furthermore, by making the conductor connection part 31 cylindrical, making a part of the bushing conductor 12 hollow, and making an electrical connection between the outer periphery of the conductor connection part 31 and the inner periphery of the bushing conductor, it is possible to make a relatively large ceramic pipe. It became possible to absorb dimensional tolerances in this part, making assembly work easier.

In addition, a bushing conductor 1 is provided on the surface of the support flange 5.
By providing a taper perpendicular to 2, the conductor connection portion 31 of the bushing can be easily attached.

[Effects of the Invention] As described above, according to the present invention, the fixed-side bushing conductor is disposed in the conductor connection portion formed on the fixed-side support flange of the insulating tube, so that the locking portion of the bushing conductor is connected to the conductor. The fixed contact part can be attached and detached from the support flange while connected to the connection part, and the work of attaching and detaching the bushing conductor is omitted, which greatly reduces the work required for inspection and eliminates power outages associated with work. This has the effect of shortening the time.

Note that by integrally forming the conductor connection portion with the support flange, the number of parts is reduced, so assembly time can be shortened and reliability can also be improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the breaking section of the circuit breaker of the present invention, and FIG. 2 is a sectional view of the breaking section of a conventional circuit breaker. DESCRIPTION OF SYMBOLS 1...Tank, 2...Fixed side contact part, 3...Movable side contact part, 4...Insulating cylinder, 5...Fixed side support flange, 6
...Movable side support flange, 7...Fixed arc electrode, 8
...Fixed main current-carrying contact, 9...Fixed electrode support, 10...
Connection conductor, 11, 23... Insulator pipe, 12... Bushing conductor, 13... Upper flange, 14... Operation rod,
15... puffer cylinder, 16... puffer piston, 17... puffer chamber, 18... movable arc electrode,
19... Insulating nozzle, 20... Movable main energizing contact, 2
1... Conductor energizing contact, 22, 31... Conductor connection part,
32...Locking part.

Claims (1)

[Scope of Claims] 1. A fixed side contact part and a movable side contact part are provided facing each other with an insulating tube in between, in a metal container filled with an arc-extinguishing gas, and the fixed side contact part side end of the insulating tube is In the circuit breaker, a metal support flange is installed at the base end of the bushing conductor, and a conductor connection part of the bushing conductor is formed on the support flange, and a metal support flange is installed at the base end of the bushing conductor. A circuit breaker characterized in that a locking portion is provided, and the locking portion of the bushing conductor is connected to the conductor connection portion. 2. The circuit breaker according to claim 1, wherein the conductor connection portion is integrally formed with the support flange.