JPH07114846A - Lightning arrester unit, lightning insulator device provided with this unit and manufacture of lightning insulator device - Google Patents

Abstract

PURPOSE:To facilitate practice also on an existing insulator by preventing an insulator main unit from being damaged, even when a resistor element is damaged by receiving a lightning surge, so that supporting an electric wire insulated can be ensured and no large arranging space is required. CONSTITUTION:A lightning arrester unit 12 is constituted by arranging respectively the first/second electrodes 16, 18 on both ends of an insulating tube 13 having prescribed strength and by interposing a resistor element 20, having a non-linear voltage-current characteristic, between both electrodes 16, 18. A lightning insulator device is manufactured by arranging the lightning arrester unit 12 through space in the periphery of an insulator main unit 1, and in this condition, by mold coating rubber in a metal mold. The first aerial discharge distance G1 is formed between the first electrode 16 and an electric wire 6, and the second aerial discharge distance G2 is formed between the second electrode 18 and a base metal fixture 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightning protection unit used for insulating and supporting an electric line and protecting it from a lightning surge, a lightning protection insulator device including the lightning protection unit, and a method for manufacturing the lightning protection insulator device.

[0002]

2. Description of the Related Art Heretofore, as an insulator having this type of lightning protection function, there have been known those having a structure as shown in, for example, Japanese Utility Model Publication No. 64-5305 or Japanese Utility Model Publication No. 1-29934.

That is, in the former insulator, the insulator body is formed in a hollow shape, and a resistance element having a non-linear voltage-current characteristic is hermetically housed in the hollow portion. Further, in the latter insulator, a lightning protection unit in which a side portion of the insulator body is covered with rubber or the like and has a built-in resistance element is additionally provided in parallel at a predetermined interval.

[0004]

However, in the former conventional insulator, when an excessive lightning surge destroys the resistance element, a follow current flows in the insulator body, and due to high heat and pressure impact of the follow arc, the insulator body is damaged. At the same time, the wire was damaged, and at the same time, there was a problem that it caused a secondary disaster such as a fall of an electric wire. Therefore, there is also a problem that it is necessary to provide a mechanism for protecting the insulator body such as a pressure release mechanism.

Further, in the latter conventional insulator, since the lightning protection unit is arranged on the side of the insulator body, there is a problem that it occupies a space on the electric pole and is apt to hinder the work on the pole.

The present invention has been made by paying attention to the problems existing in the prior art. The purpose thereof is to provide a lightning protection unit and a lightning protection insulator including the lightning protection unit, which can avoid the possibility of damaging the insulation support of the electric wire without damaging the insulator main body even if the resistance element is destroyed due to a lightning surge. An object of the present invention is to provide a device and a method of manufacturing a lightning protection insulator device.

Another object of the present invention is to manufacture a lightning protection unit and a lightning protection device and a lightning protection device, which can be easily implemented on an existing insulator without requiring a large space for arrangement. To provide a method.

[0008]

In order to achieve the above-mentioned object, in the invention of the lightning protection unit according to claim 1, the first electrode is provided at each end of the cylindrical support having a predetermined strength. The second electrode is provided, and a resistance element having a non-linear voltage-current characteristic is sandwiched between the two electrodes.

Further, in the invention of the lightning arrester device including the lightning protection unit according to the second aspect, a cylindrical support having a predetermined strength is provided on the outer periphery of the elongated insulator through the rubber-like elastic body. And a first electrode and a second electrode are provided on both ends of the cylindrical support, respectively, and a resistance element having a non-linear voltage-current characteristic is sandwiched between the electrodes, and the outer circumference of these elements is The rubber-like elastic body is formed by molding.

Further, in the invention of the method for manufacturing a lightning arrester device according to the third aspect, the first electrode and the second electrode are arranged at both ends of the cylindrical support having a predetermined strength, and both electrodes are provided. A lightning protection unit in which a resistance element having a non-linear voltage-current characteristic is sandwiched therebetween is disposed on the outer circumference of a long insulator via a spacer, and then a gap between the insulator and the cylindrical support is formed. It is characterized in that the outer peripheral portion of the lightning protection unit is mold-coated with a rubber-like elastic body.

[0011]

In the lightning arrester device provided with the lightning protection unit of the present invention, the cylindrical support having a predetermined strength is arranged on the inner peripheral portion of the resistance element even if the resistance element is destroyed due to a lightning surge. The cylindrical support shields the impact due to the destruction. Therefore, the insulator main body located inside the tubular support body is not likely to be damaged, and thus it is possible to avoid the possibility of impairing the insulation support of the electric wire.

Further, this lightning protection unit is arranged on the outer peripheral portion of the insulator body with a spacer interposed therebetween, and in this state, the rubber-like elastic body is covered with the mold, whereby the insulator body is easily manufactured. Since this lightning protection unit is mounted so as to surround the insulator body, it does not require a large arrangement space and can be easily implemented on an existing insulator.

[0013]

Embodiments (First Embodiment) Embodiments embodying the present invention in a lightning protection unit, a lightning protection insulator device and a method for manufacturing the same, which are used in a non-ceramic insulator as an electric wire support insulator, will be described below with reference to FIGS.

As shown in FIG. 1, an insulator main body 1 made of FRP (glass fiber reinforced plastic), which constitutes an elongated insulator, is composed of a cylindrical body portion, and an FRP reinforcement member is provided on the outer periphery of the upper end thereof. The layer 2 is fixed. The reinforcing layer 2 has a male screw portion on the outer periphery thereof, and a metal wire support 3 is screwed and fixed to the male screw portion. The electric wire support 3 includes a large-diameter collar portion 4 and an annular electric wire groove 5, and an electric wire 6 as a power applying portion is fixed to the electric wire groove 5 by a bind wire or the like. An insulating cover C for insulation protection is attached to the upper end of the insulator body 1.

The base metal fitting 8 as the grounding portion is the insulator body 1
It is screwed and fixed to the male screw portion of the reinforcing layer 7 fixed to the outer periphery of the lower end of the base metal fitting 8, and a pin metal fitting 9 is provided at the lower portion of the base metal fitting 8 so as to project therefrom. The insulator body 1 is installed on a utility pole (not shown) by tightening and fixing the pin fitting 9 to the ground fitting 11 such as a braid with a nut 10.

The lightning protection unit 12 is attached and fixed to the intermediate portion of the insulator body 1 in a close contact state. That is, FRP
The insulating cylinder 13 as a cylindrical support having a predetermined strength is formed by the internal insulation that constitutes a part of the insulating coating layer 14 made of ethylene-propylene copolymer rubber (EPR) on the outer peripheral surface of the insulator body 1. It is arranged via the layer 15. The lightning protection unit 12 is tightly fixed to the insulator main body 1 to shield the insulator main body 1 from the lightning protection unit 12.

The tip of the first electrode 16 is bent upward, and is fixed by screwing a nut 17 onto the upper end of the insulating cylinder 13. Then, a predetermined first air discharge distance G1 is formed between the tip of the first electrode 16 and the electric wire 6 as the power applying unit. A tip of the second electrode 18 is bent downward, and a nut 19 is screwed to the lower end of the insulating cylinder 13 to fix the second electrode 18. Then, the second electrode 18
A predetermined second air discharge distance G2 is formed between the tip of the base metal member 8 and the base metal fitting 8.

As shown in FIGS. 2 and 3, zinc oxide (Zn
O), which has a non-linear voltage-current characteristic
Are formed in an arc shape and are sandwiched and held between the first and second electrodes 16 and 18 so as to face each other.

As shown in FIG. 1, the insulating coating layer 14 is integrally molded with the internal insulating layer 15 by the EPR so as to cover the insulating cylinder 13, the resistance element 20, and the like. The insulation strengthening layer 21 is formed in the gap between the insulating cylinder 13 and the resistance element 20 during molding. The cylindrical fold 22 is formed under the insulating coating layer 14 and covers the second electrode 18 extending downward.

As shown in FIG. 3, a pair of upper and lower spacers 23 made of foamed rubber have an arc shape and are fixed to the upper and lower ends of the inner peripheral surface of the insulating cylinder 13 so as to face each other. The inner diameter of the spacer 23 is set to be substantially the same as the diameter of the insulator body 1. When the lightning protection unit 12 is mounted on the outer circumference of the insulator body 1, the lightning protection unit 12 can be positioned.

Next, a method of manufacturing the lightning protection insulator device, that is, a method of mounting the lightning protection unit 12 on the insulator body 1 will be described. As shown in FIG. 4, first, with the base metal fitting 8 not attached to the insulator body 1, the lightning protection unit 12 configured as described above is inserted from the lower portion of the insulator body 1. At this time, the inner diameters of the spacers 23 provided above and below the inner peripheral portion of the lightning protection unit 12 are formed to be substantially the same as the diameter of the insulator main body 1, and the lightning protection unit 12 is positioned with respect to the insulator main body 1.

Then, in that state, it is placed in a mold (not shown), rubber of EPR is injected, and a rubber layer is molded. As a result, as shown in FIG. 1, the inner insulating layer 15 is formed in the gap between the insulator body 1 and the insulating cylinder 13, and the outer periphery of the other insulator body 1 and the lightning protection unit 12 are formed.
An insulating coating layer 14 is formed on the outer periphery of the.

Next, the base metal fitting 8 is screwed onto the lower end portion of the insulator main body 1, and the pin metal fitting 9 is fastened and fixed to the grounding metal fitting 11 by the nut 10, whereby the insulator main body 1
Is supported on a utility pole (not shown), and a lightning protection insulator device is manufactured.

Next, the operation of the lightning arrester device having the lightning protection unit 12 constructed as described above will be described.
Now, in the lightning arrester device of this embodiment, when a lightning surge enters the electric wire 6, this lightning surge flashes over the first air discharge distance G1 from the electric wire 6 to the resistance element 20 via the first electrode 16. Flowing. After that, flashover occurs from the tip of the second electrode 18 through the second air discharge distance G2, and discharge is performed through the base metal fitting 8 and the ground metal fitting 11. Therefore, the voltage rise of the line is suppressed, and the follow-up current is blocked by the resistance element 20 and the air discharge distances G1 and G2.

The lightning protection unit 12 of this embodiment is mounted on the outside of the insulator body 1 in close contact with it, and the resistance element 2
An insulating cylinder 13 having a required rigidity is arranged inside 0. Therefore, even if the resistance element 20 is destroyed by an excessive lightning surge, the insulating cylinder 13 shields the high heat and pressure shock of the follower arc. Moreover, the resistance element 20
Is in a state of being enclosed in the insulating coating layer 14 made of an elastic rubber layer, the follower arc is diffused to the outer peripheral region of the insulator body 1, and is shielded and relaxed by the insulating coating layer 14. Therefore, the insulator body 1 is not likely to be damaged, and the insulation and support of the electric wire 6 can be prevented from being hindered.

In addition, in this embodiment, since the lightning protection unit 12 is concentrically mounted on the outer periphery of the insulator body 1, a large space for the lightning protection unit 12 is required on the side of the insulator body 1. Not. As a result, it is possible to easily mount the lightning protection unit 12 even on an existing insulator. (Second Embodiment) Next, a second embodiment of the present invention embodied in a lightning arrester unit, a lightning arrester device and a method for manufacturing the same, which are used in a non-ceramic insulator as a tension insulator device, will be described with reference to FIG. In this embodiment, the parts different from the first embodiment will be mainly described.

As shown in this figure, a cap metal fitting 26 having a mounting hole 25 is screwed and fixed to one end of the insulator body 1, and an electric wire (not shown) is mounted and supported on the mounting metal fitting 26. The other cap fitting 28 having the support hole 27 is screwed and fixed to the other end of the insulator body 1, and is attached and supported by the support arm of the electric pole. The insulating coating layer 14 has a plurality of cap portions 29 formed in an annular shape on the outer periphery of the lightning protection unit 12 and the outer periphery of the insulator body 1.

The first air discharge distance G1 is formed between the first electrode 16 and the inner end of the cap metal fitting 26, and the second air discharge distance G2 is between the second electrode 18 and the other cap metal fitting 28. It is formed between the ends.

When a lightning surge enters the tension insulator device of this embodiment, the lightning surge flows from the cap fitting 26 to the first electrode 16 through the first air discharge distance G1. Further, the lightning surge current passes through the resistance element 20 to the second
Flashover occurs from the tip of the electrode 18 through the second air discharge distance G2, and discharge is performed through the cap fitting 28.
Therefore, the voltage rise of the line is suppressed, and the follow-up current is blocked by the resistance element 20 and the air discharge distances G1 and G2. (Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIGS.

As shown in FIGS. 7 and 8, the plate-shaped first electrode 32 in the lightning protection unit 12 of this embodiment is disposed at one end of the resistance element 20, and is provided in a bowl-shaped washer 33 such as a coil spring. The elastic body 34 is stored. The nut 35 formed in a tray shape is screwed into the insulating cylinder 13, and the washer 33 is housed in the recess thereof. Then, the metal screws 36 and 37 screwed to the nut 35 are tightened until the washer 33 contacts the first electrode 32, and the resistance element 20 is sandwiched between the first electrode 32 and the second electrode 18. There is.

The metal screw 36 on one side is the insulating coating layer 14
The discharge portion of the first electrode 32 protrudes further upward, and the first air discharge distance G1 is formed between the tip of the first electrode 32 and the charging portion.

As the elastic body 34, as shown in FIG. 9, a columnar body made of conductive rubber is used, or the washer 33 is omitted and a metal disc spring (not shown) is provided as a single body. The metal screws 36 and 37 may be used for tightening.

Now, in this embodiment, the lightning protection unit 12
The resistance element 20 is held between the first electrode 32 and the second electrode 18 by the elastic force of the elastic body 34. Therefore, when the ambient temperature changes or the temperature change in the insulating coating molding process, the thermal stress between the respective members is relieved, and the electrical contact is stably maintained.

The present invention is not limited to the above-described embodiments, but can be embodied by arbitrarily changing the configuration as described below, for example, within the scope not departing from the spirit of the invention. (A) As shown in FIG. 6, an annular rubber layer 30 made of foamed rubber is fixed to the inner peripheral portion of the insulating cylinder 13 without molding the insulating coating layer 14 as the lightning protection unit 12 as in the above embodiment. In addition, the outer periphery of the resistance element 20 and the like is coated with the coating layer 31 made of EPR rubber. (B) In the above embodiment, one of the pair of resistance elements 20 may be replaced with an insulating spacer or the resistance element 20 may be formed in an annular shape, depending on the discharge capacity. (C) Attach the lightning protection unit 12 of the present invention to the outer circumference of the porcelain insulator. (D) The spacer 23 should be formed in an annular shape, or provided at three or more upper and lower positions. (E) Providing the lightning protection unit 12 at the lower position of the insulator body 1.

[0035]

As described above in detail, according to the lightning protection unit of the present invention, the lightning protection insulator device including the lightning protection unit, and the method of manufacturing the same, the following excellent effects are exhibited. That is,
Even if the resistance element is damaged by a lightning surge in the lightning protection insulator device, it is possible to avoid the possibility of damaging the insulation support of the electric wire without damaging the insulator main body. In addition, the lightning protection unit does not require a large arrangement space and can be easily implemented on an existing insulator. In addition, the lightning protection insulator device is easily manufactured by mounting the lightning protection unit on the outer circumference of the insulator body via a spacer and then coating the rubber-like elastic body with the mold.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing a lightning arrester device of a first embodiment embodying the present invention.

FIG. 2 is a sectional view showing a lightning protection unit.

FIG. 3 is a plan view showing a lightning protection unit.

FIG. 4 is a partial cross-sectional view showing a state in which the lightning protection unit is attached to the insulator body.

FIG. 5 is a partial cross-sectional view showing a tension-resistant lightning arrester device according to a second embodiment of the present invention.

FIG. 6 is a sectional view of a lightning protection unit showing another example of the present invention.

FIG. 7 is a cross-sectional view of essential parts showing a lightning arrester device according to a third embodiment of the present invention.

8 is a partial cross-sectional view showing the main parts of FIG.

9 is a partial cross-sectional view of another example of the main part of FIG. 7.

[Explanation of Codes] 1 ... Insulator main body as elongated insulator, 12 ... Lightning protection unit, 13 ... Insulating cylinder as tubular support, 14 ... Insulating coating layer, 15 ... Internal insulating layer, 16 ... First Electrode, 18 ... Second
Electrode, 20 ... Resistance element, 32 ... First electrode, G1 ... First air discharge distance, G2 ... Second air discharge distance.

Claims (3)

[Claims] 1. A first electrode and a second electrode are arranged at both ends of a cylindrical support having a predetermined strength, and a resistance element having a non-linear voltage-current characteristic is sandwiched between the two electrodes. A lightning protection unit that is characterized. 2. A tubular support having a predetermined strength is provided on the outer periphery of a long insulator via a rubber-like elastic body, and a first electrode and a second electrode are provided at both ends of the tubular support, respectively. And a resistance element having a non-linear voltage-current characteristic is sandwiched between both electrodes, and a rubber-like elastic body is molded on the outer periphery of the resistance element. Insulator device. 3. A first electrode and a second electrode are arranged at both ends of a cylindrical support having a predetermined strength, and a resistance element having a non-linear voltage-current characteristic is sandwiched between the two electrodes. After arranging the lightning protection unit on the outer periphery of the elongated insulator via a spacer, the gap between the insulator and the cylindrical support and the outer periphery of the lightning protection unit are mold-coated with a rubber-like elastic body. And a method for manufacturing a lightning protection insulator device.