JPS6010250Y2 - Insulator with built-in lightning arrester - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an insulator with a built-in lightning arrester that prevents an insulated wire from melting due to arc current caused by lightning surges or follow-on current.

In order to modernize and make power distribution equipment safer, distribution lines are being insulated, and this project is nearing completion nationwide.

When a lightning surge enters such an insulated wire, the insulation is destroyed at the damaged location, especially near the insulator, and follow-on arcs are concentrated at the insulation breakdown point, causing damage and melting of the distribution line. do.

To prevent this, lightning arresters have been installed at important points, but wire breaks have occurred at the pillars where lightning arresters are not installed between the pillars where lightning arresters are installed.

This also applies even if an overhead ground wire is installed.

Therefore, in order to completely eliminate this type of damage and melting of distribution lines, each company must install lightning arresters.

However, installing lightning arresters at each company is difficult because they must be placed in combination with supporting insulators and lead wires must be attached separately.
This is economically expensive and aesthetically undesirable.

In view of the above, the present invention has been developed to provide an insulator with a built-in lightning arrester, which simplifies the relatively difficult installation process by integrating the lightning arrester and the insulator, in order to accurately prevent the damage and melting of the covered distribution line mentioned above. It provides:

Also, Utility Model Publication No. 55-22923 and Utility Model Publication No. 32-38
The insulator described in the 3rd report is one that clamps the wire between the insulator and the wire locking device, and as a means of fixing the wire locking device to the insulator, a bolt is driven directly into the insulator (screwing). )
things are being done.

However, if the insulator and the metal fixture (bolt) are in contact with each other, there is a problem that the contact part of the insulator is easily damaged by the metal fixture when external force (tension, torsion force, impact) is applied. be.

Due to damage, cracks, etc. occurring in the contact area,
This often results in the insulator falling off or being destroyed.

If the insulator has a built-in lightning arrester, the lightning arrester will be exposed to the outside air, resulting in problems such as deterioration of characteristics.

In addition, as an insulator with a built-in lightning arrester, the above Jikosho 32-3
In addition to Publication No. 83, there are those described in Japanese Utility Model Publication No. 49-22332, and in all of these, the internal space of the insulator has a sealed structure, which prevents condensation inside the space due to fluctuations in external temperature. I can't.

For this reason, there is a risk that the characteristics of the lightning arrester built into the insulator may deteriorate early.

That is, the insulator with a built-in lightning arrester according to the present invention has an insulator having a hollow portion penetrating in the axial direction, and a wire holding device that is fixed to the upper end opening of the insulator by cementing. an upper metal fitting that holds the insulator; a lower metal fitting that is fixed to the lower end opening of the insulator by cementing and has a bolt that projects downward; and a lower metal fitting that is housed in the hollow part of the insulator without contacting the inner wall of the insulator. a lightning arrester set having an electrode at its upper end electrically connected to the electric wire via the upper metal fitting, and an electrode at its lower end electrically connected to the lower metal fitting and the bolt; A vent hole that penetrates the insulator and communicates the hollow part of the insulator with the outside, It is characterized by having

The insulator with built-in lightning arrester of the present invention will be described in detail below with reference to the accompanying drawings.

The attached drawing shows an embodiment of the present invention, which shows a distribution line 1 from which the insulation coating has been stripped over a required length, a wire holder 2 that fixedly holds the distribution line 1, and a wire holder 2 that fixedly supports the wire holder 2. It has an upper metal fitting 3 and a bolt 5a attached to the cross arm 4, and a ventilation hole 5b passing through the center (-in the example, about 57177Iφ,
A lower metal fitting 5 having a length of about 13 cm and a space of about 3 cm, an insulator 6 located between the upper metal fitting 3 and the lower metal fitting 5 and having a hollow part 6a, and an insulator 6 in the hollow part 6a. The spring holder connected to the lower hardware 5 is received by the spring 7, and the lightning arrester set holder connected to the upper hardware 3 is pushed up toward the conductor 3a by the spring 7.
(In the - example, the lightning arrester set 8 was arranged in the hollow part 6a to form a remaining space of about 20 CI) and the loose rubber bushings inserted between the upper bottom surface of the insulator 6 and the upper and lower metal fittings 3 and 5, respectively. 9, 10, cementing 11 mainly made of, for example, epoxy resin, which adheres the insulator 6 and the upper and lower metal fittings 3, 5, respectively, and dirt provided in the ventilation hole 5b.
A ventilating backing 12 that prevents insects from entering, a labyrinth path 13 made of, for example, vinyl chloride resin and having a spring holder located in the portion 5c, and a ground side electrode of the lightning arrester set 8 and the lower metal fitting 5 are connected. In order to do this, the spring receiver has a lead conductor 14 provided in the portion 5c.

The lightning arrester set 8 located inside the hollow part 6a of the insulator 6 has a series air gap and a lightning arrester element having excellent follow-current characteristics such as ZnO (zinc oxide), and has connection electrodes 8 on the top and bottom.
A and 8b are exposed and are integrally formed into a sealed structure using, for example, epoxy or rubber.

One of the electrodes 8a is connected to the distribution line 1 through the conductor 3a and the upper metal fitting 3, the other electrode 8b is connected to the lead conductor 14, and the spring receiver is connected to the part 5c, the lower metal fitting 5 and the arm 4. is grounded through.

Further, the labyrinth path 13 has a first path leading to the ventilation hole 5b.
The opening 13a has an opening 13a and a second opening 13b communicating with the hollow portion 6a, and a detour extending in a spiral shape is formed between the first and second openings 13a and 13b.

The detour has a predetermined volume and has the same effect on breathing as the vent hole 5b, which will be described later, has, so if it is provided, the diameter of the vent hole 5b can be reduced to about 3rrrln.

In the above configuration, the port) 5 connected to the lower hardware 5
After attaching the insulator with a built-in lightning arrester according to the present invention to the power distribution network, the insulator with a built-in lightning arrester according to the present invention is installed in the power distribution network by attaching the wire 1 to the cross arm 4 of each company and holding the wire 1 with the insulation coating stripped over the required length using the wire holding tool 2. be able to.

In this case, it is desirable to prevent electric shock and maintain waterproofness by placing a cover made of a molded product such as rubber over the portion of the electric wire 1 from which the insulation coating has been removed.

By installing insulators with built-in lightning arresters in each company, even if a lightning surge enters, it can be reliably discharged to the ground through the lightning arrester set, thereby preventing damage to electric wires and melting accidents.

According to the insulator with a built-in lightning arrester according to the present invention explained above,
The following advantages can be mentioned.

(1) Since general standard insulators can be used depending on the voltage class, manufacturing is easy and manufacturing costs can be reduced.

In particular, in the 6KV class, it was necessary to use a special material, porcelain, to prevent damage to the insulator due to creeping arcs caused by impact current or follow-on current. ), and there are no restrictions on manufacturing.

(2) It is possible to provide a predetermined value for the mechanical stress generated by holding electric wires by appropriately selecting the thickness of the insulator, the shape and thickness of the upper and lower hardware, the adhesive area, etc. can.

(3) The daily temperature difference is up to 20℃ throughout the year,
The daily respiratory rate in this state is about 14% at most.

As in the previous example, if the remaining space is 20C711, even without a labyrinth path, the maximum breathing volume will be about 3crl and the ventilation hole will be 5TIr! In the case of 11φ, the outside air taken in remains in the vent hole 5C of the lower metal fitting 5 and does not enter the inside.

In addition, if a labyrinth path is provided as in the above-mentioned embodiment, even if the ventilation hole is reduced to 2 to 37F + 771φ, approximately 15% of the intake air can be absorbed within the path. Even if heavy breathing of the order of 30% occurs, the intake air will remain within the path and outside air will not be able to reach the parts of the arrester set.

(4) According to the experimental values mentioned in (3) above, large seasonal temperature changes can occur even if the air in the remaining space is slightly replaced, because this replacement occurs little by little during daily breathing, so condensation does not occur. It will dry the next day, and any negative effects on the interior due to condensation can be ignored.

Moreover, since this is done in the lower part of the remaining space, it does not affect the sealed lightning arrester set installed in the upper part at all.

(5) Furthermore, even if some dew condensation occurs, the lightning arrester set has a sealed structure, so it will not deteriorate.

(6) Since the lightning arrester set is supported and fixed so as not to come into contact with the inner surface of the insulator, uneven potential distribution or poor creeping insulation can be prevented.

(7) Since the lightning arrester set is manufactured separately with various performance values such as discharge starting voltage set to predetermined values and is incorporated, there is no need for adjustment, etc., and uniformity of performance and reliability can be achieved.

(8) Since the cross arm serves as a common conductor on the grounding side and the connection line from the ground can be connected to any point on the cross arm, the grounding work is greatly simplified.

As explained above, according to the insulator with a built-in lightning arrester according to the present invention, since the lightning arrester and the insulator are integrated, it is possible to accurately prevent damage and melting of the covered distribution line.

[Brief explanation of drawings]

The accompanying drawings are cross-sectional views showing one embodiment of the present invention. 1... Electric wire, 2... Electric wire holding tool, 3.
...Upper hardware, 3a...Surge arrester set receiver is conductor, 4...Archive arm, 5...Lower hardware, 5a...Bolt part , 5b...Vent hole, 5c...Spring holder, 6...
Insulator, 6a...Hollow part, 7...Spring, 8...Surge arrester set, 9, 10...
...Buffer rubber bushing, 11...Cementing, 12...Vent backing, 13...
- Labyrinth path, 13a, 13b...opening, 14...lead conductor.

Claims (1)

[Claims for Utility Model Registration] An insulator having a hollow portion penetrating in the axial direction, and an upper portion that is fixed to the upper end opening of the insulator by cementing and that clamps the electric wire between the electric wire holding tool. a metal fitting; a lower metal fitting fixed to the lower end opening of the insulator by cementing and having a bolt protruding downward; A lightning arrester set having an electrode at an upper end electrically connected to the electric wire via the upper metal fitting, and an electrode at the lower end thereof electrically connected to the lower metal fitting and the bolt; The vent hole communicates the hollow part of the insulator with the outside, and the vent hole has a labyrinth path with a volume exceeding the annual maximum daily respiration volume of the hollow part of the insulator. An insulator with a built-in lightning arrester.