JPH08249964A - Insulator with built-in arrester - Google Patents

Abstract

PURPOSE: To prevent damage to an insulating covering body caused by arc jet during discharge and prevent drop in dynamic current cut-off function of a non-linear resistance element caused by effective shunt current of surge current caused by contamination of the surface of the insulating covering body. CONSTITUTION: A discharge end part 35a of an arrester 30 embedded in an insulating covering body 20 covering an insulator main body 10 is positioned within a circular groove 23b in the bottom of a cylinder 23 arranged in the insulating covering body 20, and a discharge arc is diffused in the circular groove 23b to make temporarily stay. Discharge arc released to the outside is reduced, damage and contamination of the surface of the insulating covering body 20 caused by exposure to the arc are prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention protects an electric line system by insulating and supporting electric wires such as transmission and distribution lines and discharging a lightning surge that has entered the electric line to the ground to interrupt the subsequent flow. The present invention relates to an insulator with a built-in arrester.

[0002]

2. Description of the Related Art As one type of insulator, an actual Kaihei 6-310
As disclosed in Japanese Patent Laid-Open No. 32, No. 32, the outer periphery of an insulator body having a predetermined length is covered with an insulating coating, and a non-linear resistance element forming a lightning arrester is embedded in the insulation coating to provide the same non-linear resistance. There is a lightning arrester built-in type insulator in which a discharge end connected to an element is exposed to the outside from the insulating cover. The insulator is installed on the utility pole with the electric wire support part facing up or sideways to insulate and support the transmission and distribution lines, and discharge the lightning surge that has entered the electric line by the lightning arrester to the ground to interrupt the subsequent flow. It is a thing.

[0003]

In the insulator, when a flashover occurs due to a lightning surge entering the electric line, the discharge end connected to the non-linear resistance element captures this discharge. In this case, since the insulator is installed on the overhead electric line and the surface of the insulating coating is soiled, the arc jet of the discharge from the discharge end protruding from the insulating coating spreads on the surface of the insulating coating. There is a possibility that the insulating coating may be damaged or that a surge current may be shunted to the dirty surface of the insulating coating to reduce the follow current blocking function of the non-linear resistance element.

Further, when the insulator is installed in an area with a high discharge frequency, the non-linear resistance element deteriorates quickly and the follow current blocking function of the element deteriorates early, so that the discharge arc increases. Dissolution of metal or evaporation of metal occurs at the discharge end, and molten metal or metal vapor adheres to the surface of the insulation coating to damage the surface of the insulation coating or reduce the electrical insulation function of the surface of the insulation coating. There is a risk.

Therefore, an object of the present invention is to protect the surface of the insulating cover from the arc jet from the discharge end in this type of surge arrester built-in type insulator, so that the electrical insulation function of the insulator is sufficiently long-term. It is intended to maintain and stabilize the protection capability of the electric line system against lightning surges.

[0006]

According to the present invention, an insulator main body having a predetermined length is covered with an insulating coating, and a non-linear resistance element constituting a lightning arrester is embedded in the insulating coating. A lightning arrester built-in type insulator in which a discharge end connected to a linear resistance element is exposed to the outside from the insulating coating, wherein the lightning arrester built-in insulator has the insulating coating opened to one end side of the insulator body. A bottomed cylindrical body that extends concentrically with the insulator body; and an annular groove that is open at one end of the insulator body at the bottom of the insulator body and is centered on the insulator body,
The discharge end projects from the bottom of the annular groove and is located in the annular groove.

Further, according to the present invention, the outer periphery of the insulator main body having a predetermined length is covered with an insulating coating, and the non-linear resistance element constituting the lightning arrester is embedded in the insulation coating to form the non-linear resistance element. A lightning arrester built-in type insulator in which a discharge end to be connected is exposed to the outside from the insulating coating, wherein the lightning arrester built-in type insulator has the insulating coating opened to each end side of the insulator body. A pair of bottomed cylindrical bodies that extend concentrically with the main body, and annular grooves that are open at each end side of the insulator main body at the bottom of each of the cylindrical bodies and are centered on the insulator main body are provided. The discharge end portions are respectively projected from the bottom portion of and are located in the respective annular grooves.

In the arrester with a built-in arrester according to the present invention, the peripheral surface of the annular groove of the insulating coating is covered with a conductive coating, and the insulating coating has an annular shape facing the opening of the cylindrical body. A mode in which a fold portion is formed, or the like can be adopted.

[0009]

In the insulator with a built-in arrester having such a structure, an annular groove provided at the bottom of the cylindrical body in which the discharge end connected to the non-linear resistance element is provided in the insulating cover is provided. The discharge arc from the discharge end once stays in the annular groove and is diffused in the cylinder and the opening of the cylinder because it is located inside the cylinder and does not protrude from the bottom of the cylinder. Released from the department. For this reason, damage and contamination of the surface of the insulating coating are reduced. Further, when metal dissolution, metal evaporation, etc. occur at the discharge end, the dissolved metal, evaporated metal, etc. once stay in the annular groove and diffuse,
It is discharged into the cylinder and to the outside through the opening of the cylinder. For this reason, damage to the insulating coating body due to molten metal, evaporated metal, or the like is reduced, and deterioration of the electrical insulating function of the insulating coating body is suppressed to maintain the same function for a long period of time.

Further, in the lightning arrester built-in insulator, since the surface of the insulating coating is prevented from being soiled and moistened around the disposing portion of the discharge end, the discharge arc spreads to the surface of the insulating coating. And the shunting of surge current are reduced, and the deterioration of the blocking function of the continuous current of the nonlinear resistance element is reduced.
This function is stably maintained for a long period of time.

In the lightning arrester built-in type insulator, if the peripheral surface of the annular groove of the insulating coating is covered with a conductive coating, the current accumulated in the annular groove is effectively dispersed and the insulating coating is formed. It is possible to prevent local discharge on the body surface. Further, in the lightning arrester built-in type insulator, if the insulating cover is formed with an annular fold facing the opening of the cylinder, it is possible to prevent wind and rain from being blown into the cylinder, and the discharge end, the annular groove, and It is possible to prevent the inner peripheral wall of the cylindrical body from being soiled or wetted.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the drawings. FIG. 1 shows a lightning arrester built-in insulator according to the present invention. The insulator comprises an insulator body 10 and an insulating cover 2.
0 and a lightning arrester 30. The insulator main body 10 is a rod-shaped member having a predetermined length and formed of fiber-reinforced plastic having long fibers as a reinforcing member. The upper and lower ends of the rod portion 11 are provided with cylindrical connecting metal fittings 12, 13. ing. Each of the connecting fittings 12 and 13 penetrates the rod portion 11 in the radial direction and is integrated with the rod portion 11 when the insulator main body 10 is molded.

In forming the insulator main body 10, as shown in FIG. 5, both connecting metal fittings 1 are first arranged at a predetermined interval.
The long fibers are repeatedly wound around the annular recesses 12a and 13a in the central portions of the Nos. 2 and 13 and held in a bundle, and the bundle of fiber groups 14
The thermosetting resin 15 is impregnated in and cured. As a result, the insulator main body 10 having the connecting fittings 12 and 13 penetrating through the upper and lower ends of the rod portion 11 is formed. Glass fiber or the like is used as the long fiber, and unsaturated polyester resin, epoxy resin or the like is used as the thermosetting resin.

The insulating cover 20 is made of an electrically insulating elastic member such as silicon rubber, ethylene propylene rubber, butadiene styrene rubber, etc., and is used for all of the insulator body 10 except the open ends of the metal fittings 12, 13. Is provided with a cylindrical covering portion 21 for covering the outer peripheral surface thereof, and the covering portion 21 is provided with a cylindrical embedded portion 22 on the outer periphery of the central portion in the longitudinal direction, and at each end portion of the embedded portion 22 in the longitudinal direction. The bottomed tubular portions 23 and 24 extending toward the respective end sides of the portion 21 are provided, and a plurality of pleats 25a, 25b, 26a and 26b are provided on the outer periphery of the covering portion 21 at a position separated from the tubular portions 23 and 24. Has been formed. These parts 21 to 26 are integrally formed.

As shown in FIGS. 1, 2 and 4, the arrester 30 is a pair of non-linear resistance elements 3 each having an arc shape and a predetermined length.
1, 32, a pair of electrode plates 33, 34 for sandwiching the both non-linear resistance elements 31, 32 on the same circumference by sandwiching them at their both ends, and an outer surface of each electrode plate 33, 34. It is composed of a plurality of projecting discharge ends 35a and 35b. The lightning arrester 30 is embedded in the embedded portion 22 of the insulating cover 20, and each of the nonlinear resistance elements 31,
32 is located concentrically with respect to the insulator body 10.

In the insulator, however, the cylindrical bodies 23 and 24 of the insulating coating 20 are open toward the respective end portions of the coating portion 21 and gradually expand to extend to the bottom portions 23a and 2 thereof.
4a includes annular grooves 23b and 24b centered on the covering portion 21.
Are formed. In each of the annular grooves 23b and 24b, the outer peripheral edge portion has a tapered shape that expands outward,
Their peripheral surfaces are covered with conductive coatings 23c and 24c. Each discharge end portion 35a, 35 forming the lightning arrester 30
b projects from the bottom portions 23a, 24a of the cylindrical bodies 23, 24 and is located in the annular grooves 23b, 24b. Each pleated portion 25a, 25b, 26a, 2 provided on the insulating cover 20
The pleats 25b and 26b on the central side of 6b are located opposite the openings of the cylinders 23 and 24, respectively.

In the thus-configured insulator with a lightning arrester, the connecting pin 1 having one end inserted through the connecting fitting 12
6 is connected to a strap 17 on the utility pole side, and an electric wire clamp (not shown) is connected to the other end side via a connecting metal fitting 13. Used for holding electric wires. In addition, in such a usage state, the insulator has the following operational effects.

(1) In this insulator, when a flashover occurs between the connecting fittings 12 and 13 due to a lightning surge that has entered the electric line, this discharge is in the middle of the discharge path.
The non-linear resistance elements 31 and 32 are captured via 5a and 35b. Since the discharge ends 35a and 35b are located in the respective annular grooves 23b and 24b, the arc jet of the discharge once diffuses and stays along the circumferential surfaces of the annular grooves 23b and 24b. Therefore, the bottom portion 23 of the tubular body 23, 24
The forward arc density of a and 24a is reduced, and
The arc exposure in the inner and outer regions of 3, 24 is reduced, and the damage to the insulating cover 20 is prevented.

(2) In the insulator, the non-linear resistance elements 31 and 32 are deteriorated due to the increase in the discharge frequency, the discharge arc is increased, and metal dissolution and metal evaporation occur at the discharge ends 35a and 35b. Also, the molten metal and the evaporated metal are in the annular groove 23.
The annular groove 2 is diffused and temporarily stays in b and 24b.
The scattering of 3b, 24b to the outside is reduced, and the cylindrical bodies 23, 2
It is possible to prevent deterioration of the electrical insulation function of the insulating cover 20 due to metal damage and stains in the inner and outer regions of 4.

(3) In the insulator, the discharge end portion 35
Since the a and 35b are located in the annular grooves 23b and 24b and are surrounded by the circumferential surfaces of the grooves 23b and 24b, the surface of the insulating coating body 20 that is close to the discharge ends 35a and 35b. Since the contamination and wetting of the non-linear resistance elements 31 and 32 due to the contamination of the insulating coating 20 and the spread of the arc jet to the wetting surface and the shunting of the discharge current are prevented from being reduced.

(4) In the insulator, the insulating coating 2
Since the fold portions 25b and 26b facing the openings of the tubular bodies 23 and 24 are provided in the covering portion 21 of 0, the tubular bodies 23 and
The blowing of wind and rain into the inside 24 is reduced, and the discharge end 35
Around the a and 35b, fouling and wetting are suppressed, and the electric insulation function and the follow current interruption function of the non-linear resistance elements 31 and 32 are prevented from being deteriorated.

(5) In the insulator, the annular groove 23
Since the peripheral surfaces of b and 24b are coated with the conductive coatings 23c and 24c, the discharge current accumulated in the annular grooves 23b and 24b is effectively dispersed, and local discharge in the insulating coating 20 is prevented. To be done.

(6) In the insulator, the insulating coating 2
The cylinders 23 and 24 provided in 0 are the power-supply side of the insulator body 10,
Each discharge end 35 has an opening on the ground side.
The arc inducing property of the discharge from a and 35b is improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a lightning arrester built-in insulator according to an embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view of a portion with a built-in arrester in the insulator.

FIG. 3 is an enlarged cross-sectional view of the insulator seen in the direction of arrow 3-3 in FIG.

FIG. 4 is an enlarged cross-sectional view of the same insulator as seen in the direction of arrow 4-4 in FIG.

FIG. 5 is an explanatory view showing a method for forming an insulator main body that constitutes the same insulator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Insulator main body, 11 ... Rod part, 12, 13 ... Connection metal fittings, 20 ... Insulating coating, 21 ... Covering part, 22 ... Embedded part,
23, 24 ... Cylindrical body, 23a, 24a ... Bottom part, 23b, 2
4b ... annular groove, 23c, 24c ... conductive coating, 25a,
25b ... folds, 26a, 26b ... folds, 30 ... lightning arresters, 31, 32 ... non-linear resistance elements, 33, 34 ... electrode plates, 35a, 35b ... discharge ends.

Claims (4)

[Claims] 1. A discharge end in which an outer periphery of an insulator body having a predetermined length is covered with an insulating coating, and a non-linear resistance element forming a lightning arrester is embedded in the insulation coating and connected to the non-linear resistance element. In a lightning arrester built-in insulator in which a portion is exposed to the outside from the insulating coating, the insulating coating has a bottomed cylindrical body that opens at one end of the insulator main body and extends concentrically with the insulator main body, An annular groove that is open at one end of the insulator body at the bottom of the cylinder and is centered on the insulator body;
A lightning arrester built-in insulator, wherein the discharge end projects from the bottom of the annular groove and is located in the annular groove. 2. A discharge end in which an outer periphery of an insulator body having a predetermined length is covered with an insulating coating and a non-linear resistance element forming a lightning arrester is embedded in the insulation coating and connected to the non-linear resistance element. In a lightning arrester built-in insulator whose part is exposed to the outside from the insulating coating, a pair of bottomed cylindrical bodies in which the insulating coating opens toward each end of the insulator body and extends concentrically with the insulator body And an annular groove that is open at each end of the insulator body at the bottom of each of the cylinders and is centered on the insulator body, and the discharge end projects from the bottom of each of the annular grooves. An insulator with a built-in arrester characterized by being located in an annular groove. 3. The arrester with a built-in arrester according to claim 1 or 2, wherein the peripheral surface of the annular groove is covered with a conductive film. 4. The arrester with a built-in arrester according to claim 1, 2 or 3, wherein the insulating cover has an annular fold facing the opening of the tubular body. Type insulator.