JPS62274511A - Lightningproof insulator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention Object of the Invention (Field of Industrial Application) This invention relates to a lightning insulator with a power transmission line support function used in a power transmission line.

(Prior art) As a conventional lightning insulator for power transmission lines, for example,
There was one disclosed in Publication No. 736.

As shown in FIG. 8, this lightning insulator has a short cylindrical non-linear resistance element in the middle of an elongated reinforced plastic body 42 which is penetrated through a cylindrical insulator 41 and has both ends protruding from both ends of the insulator 41. 43 are loosely fitted in an appropriate number, and both ends of the reinforced plastic body 42 are closed with cap fittings 45 and 46, and a non-linear resistance element is loosely fitted in the reinforced plastic body 42 within the insulator 41. 43
is held between the cap fittings 45 and 46 via an elastic body 47.

(Problem to be Solved by the Invention) However, since the conventional lightning insulator has a plurality of non-linear resistance elements 43 stacked in series without any gaps, the insulator 4
1 with a rubber mold, it is difficult for rubber to enter between the non-linear resistance element 43 and the reinforced plastic 42, resulting in poor production efficiency, and the non-linear resistance element 43
There is a problem in that when an abnormal current flows due to a lightning strike and a flash short circuit occurs on the inner surface of the element, the internal pressure increases and the nonlinear resistance element 43 is easily damaged.

Structure of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, the first invention provides a method in which a central hole of a group of vertically long cylindrical non-linear resistance elements in which cylindrical non-linear resistance elements are connected in series is provided. An injection/pressure release path passes through the tension-resistant insulation rod, connects gripping fittings to both upper and lower ends of the cough-resistant tension insulation rod, and communicates the inside and outside of the non-linear resistance element group with the connecting portion of the non-linear resistance element. An annular spacer with a ring-shaped spacer is interposed therebetween, the tension-resistant insulating rod, the non-linear resistance element group, and the spacer are integrally contained in a rubber mold, and an arcing ring is provided on each of the gripping metal fittings. ing.

In a second invention, in order to solve the above problem, a tension insulating rod is passed through the center hole of a vertically long cylindrical nonlinear resistance element group in which cylindrical nonlinear resistance elements are connected in series, and the tension insulating rod is Grip fittings are connected to both upper and lower ends of the non-linear resistance element, and an annular spacer provided with an injection/pressure release path that communicates the inside and outside of the non-linear resistance element group is interposed in the connection part of the non-linear resistance element. On the outer periphery of the linear resistance element group, a tension-resistant insulating cylinder is provided with a large number of injection/pressure release holes approximately evenly spaced with slight gaps on the outer periphery of the non-linear resistance element group using the gripping metal fittings. , the tensile insulating rod, the group of non-linear resistance elements, and the spacer are integrally enclosed in a rubber mold, and furthermore, arcing rings are provided on each of the gripping metal fittings.

(Function) Since the first invention employs the above means, it functions as follows.

During rubber molding, the rubber enters the gap between the outer circumferential surface of the tension-resistant insulating rod and the inner circumferential surface of the nonlinear resistance element group from the injection pressure path of the spacer, so that charging of the rubber is performed easily and quickly. Rubber molding becomes easier. In addition, even if an abnormal current flows through the non-linear resistance element group due to a lightning strike and the internal pressure increases, the pressure escapes to the outside from the injection/pressure relief path of the spacer, so pressure relief is performed smoothly and the non-linear Damage to the resistance element group is prevented.

In addition to the effects of the first invention described above, the second invention can improve safety by preventing the non-linear resistance element group from scattering even in the unlikely event that the non-linear resistance element group is damaged due to the tension-resistant insulating tube. .

(Example) Hereinafter, an example embodying the present invention will be described based on FIGS. 1 to 7.

As shown in FIG. 7, a lightning insulator 4 is swingably attached to the hanging fitting 2 of the steel tower 1 via a connecting pin 3. Also, a connecting pin 5 and a hanging metal fitting 6 are provided at the lower end of the lightning insulator 4.
The power line is gripped through the

Therefore, the structure of the lightning insulator 4 will be explained in detail based on FIGS. 1 to 6. An elongated cylindrical tension insulating rod 7 made of reinforced plastic (FRP) has a cylindrical shape on the outer periphery at both upper and lower ends. The gripping fittings 8.9 are firmly caulked and fixed at their thin portions 8a, 9a. Between the gripping fittings 8 and 9 are a plurality of cylindrical nonlinear resistance elements 10 made of, for example, zinc oxide and having nonlinear voltage-current characteristics.
10 are interposed in a stacked state in series, forming a non-linear resistance element group 10A as a whole. As shown in FIGS. 2 and 4, a thin metallicon 11 is formed by metal spraying on both the upper and lower end surfaces of each non-linear resistance element 10 to 10, and between adjacent metallicons 11 and 11 are copper and aluminum, respectively. A spacer 12 having an annular shape and an upper and lower thin plate electrode 13 made of lead are interposed. The spacer 12 has a gap G between the outer peripheral surface of the tensile insulating rod 7 and the inner peripheral surface of the non-linear resistance element group 10A, and an injection/pressure release path a12a that serves as an injection/pressure release path that communicates with the outside. They are formed at multiple locations (four locations in this embodiment) so that they enter the gap G from the outside during molding of the rubber mold 21, which will be described later, and also ensure smooth pressure release when the pressure within the gap G increases. I'm trying to get it done. Furthermore, a seal ring 14 made of rubber is interposed between the non-linear resistance element 10 and the thin plate electrode 13 so as to surround the outer periphery of the metallicon 11.
1 and the thin plate electrode 13.

Furthermore, an upper electrode I5 and a lower electrode 16 are interposed between the spacer 12 joined to the non-linear resistance elements 10 at the uppermost and lowermost stages and the gripping fitting 8.9. A plurality of engagement recesses 1 formed in these upper and lower electrodes 15 and 16
A coiled compression spring 17.18 is interposed between 5a, 16a and the gripping metal fitting 8.9 to press each non-linear resistance element 10 to lO into contact with each other between the gripping metal fittings 8.9, An electrically conductive shunt 19 is attached to each compression spring 17,18.

The outer periphery of the non-linear resistance element group IOA is
A pressure-resistant insulating tube 2o, which is a main part of the second invention and has a cylindrical shape and has a large number of injection/pressure relief holes 20a having the same function as the pressure relief groove 12a, has a slight gap with the non-linear resistance element group IOA. The upper and lower electrodes 15.
The position is regulated by flange portions 15b and 16b integrally formed on the outer periphery of 16. A rubber mold 21 made of EPDM rubber is integrally formed on the outer periphery of the voltage-resistant insulating tube 20, and pleats 21a are formed on the outer periphery.

In addition, the gap G between the tensile insulating rod 7 and the non-linear resistance element group 10A
Also, the injection/pressure release hole 20a and the injection/pressure release groove 12 are also provided in the gap G'' between the non-linear resistance element group 10A and the voltage-resistant insulating cylinder 20.
The rubber mold 21 entered from a is filled. Before forming the rubber mold 21, an adhesive 22 is applied to the surfaces of the tension-resistant insulating rod 7, the non-linear resistance element group 10A, and the gripping metal 8°9, so that the adhesive 22 reacts when the rubber is vulcanized. This improves the adhesion effect.

A support arm 24 is fixed to the gripping metal fitting 8.9 by a pair of brackets 23, and a notched annular cutout is provided between the tips of the support arms to avoid corona in the air and corona inside the rubber mold 21 due to electric field concentration. arcing ring 2
5.26 is installed. Further, an auxiliary arcing ring 27.28 is supported by the support arm 24 and is disposed close to the compression spring 17.18 at a position corresponding to the compression spring 17.18.

Due to the unexpected lightning strike, the element becomes conductive and an abnormal current of the commercial frequency voltage is transmitted to the grip fitting 9 and the shunt 19.
When a high-temperature, high-pressure arc flows through the non-linear resistance element group 10A through the compression spring 17 and causes a short circuit, and a high-temperature, high-pressure arc blows out from the vicinity of the compression spring 17, 18, this arc is quickly removed by the auxiliary arcing rings 27 and 28. By quickly transferring the electricity to the arcing rings 25, 26, the time for applying electricity to the gripping metal fittings 8, 9 is shortened, and heating of the gripping metal fittings 8.9 is prevented, and the heat of the gripping metal fittings 8.9 is This is to suppress the reduction in the adhesion force due to caulking with the tension-resistant insulating rod 7 due to expansion.

Next, the operation of the lightning insulator constructed as described above will be explained.

Now, a surge current due to a lightning strike flows through the power transmission line, and when it enters the lower grip fitting 9 of the lightning insulator 4 through the hanging fitting 6, this current flows through the shunt 19, the lower electrode 16, and the upper part of the nonlinear resistance element group 10A1. It flows to the electrode 15 and the upper grip fitting 8, further passes through the hanging fitting 2, flows to the steel tower 1, and is grounded. Thereafter, the resulting follow-on current is quickly interrupted because the nonlinear resistance element 10 recovers its resistance value.

Now, in the first embodiment of the invention, each nonlinear resistance element lO~10
Since the spacer 12 having the injection/pressure release groove 12a is interposed between them, the rubber mold 21 is reliably filled into the gap between each member from the injection/pressure release groove 12a during molding of the rubber mold 21, and the spacer 12 that has the injection/pressure release groove 12a is inserted between the rubber molds 21 and 21. Even if an abnormal current due to a lightning strike that exceeds flows through the non-linear resistance element 10 and the element 10 becomes conductive, pressure can be smoothly released, so the element 10
damage can be suppressed.

In this first embodiment of the invention, the gripping fittings 8.
The rubber mold 21 is formed so as to extend over a part of the outer periphery of the non-linear resistance element 9. In this case, since the entire rubber mold 21 is enclosed, the airtightness is improved and the non-linear resistance element l
Deterioration of O due to moisture can be suppressed.

In addition, in the second embodiment of the invention, the voltage-resistant insulating cylinder 20 having a large number of injection/pressure release holes 20a on the average is arranged around the outer periphery of the non-linear resistance elements 10 to 10, so that the number of non-linear resistance elements lO to
Even if 10 is about to explode and scatter, the voltage-resistant insulating tube 20 can prevent it from scattering, and the injection/pressure release hole 2Qa can suppress pressure rise to prevent damage to the voltage-resistant insulating tube 20 itself.

Note that the present invention can also be embodied as follows.

(1) Injection/pressure release groove 12a formed in the spacer 12
Instead, an injection/pressure release hole (the path shown in the figure) may be provided through the hole.

(2) The nonlinear resistance element 10 is formed into an elliptical cylinder shape.

Effects of the Invention As detailed above, the first invention makes it possible to reliably and easily integrally mold the rubber mold on the outer periphery of the tension insulating rod and the non-linear resistance element, and on the gaps between the respective members, and also solves the problem beyond expectations. Even when the non-linear resistance element becomes conductive due to an excessive lightning strike, the pressure can be easily released, preventing damage to the non-linear resistance element, and increasing safety.

In addition to the effects of the first invention, the second invention has the effect that even if the non-linear resistance element attempts to blow up or fail, it can be prevented by the voltage-resistant insulating tube.

[Brief explanation of the drawing]

Fig. 1 is a folded sectional view showing an embodiment of the present invention, Fig. '82 is an enlarged longitudinal sectional view showing the state of the joint of a non-linear resistance element before rubber molding, and Fig. 3 shows a non-linear resistance element and a non-linear resistance element. FIG. 4 is an enlarged exploded perspective view of the joint between the spacer, thin plate electrode, and non-linear resistance element; 5th FyJ shows the upper and lower electrodes. FIG. 6 is an enlarged perspective view, FIG. 6 is a perspective view of only the voltage-resistant insulating tube, FIG. 7 is a front view showing the usage state of the lightning insulator, and FIG. 8 is a longitudinal sectional view showing a conventional example. 4...Lightning insulator, 7...Tension-resistant insulation rod, 8(9)...
・Upper (lower) grip ■5.10...Non-linear resistance element, lOA...Non-linear resistance element group, 12...Spacer as injection/pressure release path, 14...Seal ring, 15
(16)... Upper (lower) electrode, 20... Voltage-proof insulating cylinder, 2Qa... Injection/pressure release hole, 21... Rubber mold, 25° 26... Arcing ring.

Claims (1)

[Scope of Claims] 1. A tension insulating rod is passed through the center hole of a group of vertically elongated cylindrical nonlinear resistance elements in which cylindrical nonlinear resistance elements are connected in series, and both upper and lower ends of the tension insulating rod are provided. Connect the gripping fittings to each,
An annular spacer provided with an injection/pressure release path communicating between the inside and outside of the non-linear resistance element group is interposed in the connection part of the non-linear resistance element, and the tension-resistant insulating rod, the non-linear resistance element group, and the spacer are connected to each other. A lightning insulator, characterized in that it is integrally enclosed by a rubber mold, and further that arcing rings are provided on each of the gripping metal fittings. 2. The lightning insulator according to claim 1, wherein the rubber mold is provided so as to extend over a part of the outer periphery of the gripping metal fitting. 3. The lightning insulator according to claim 1, wherein the gripping metal fitting is caulked and fixed to the outer periphery of the end of the tension insulating rod. 4. The lightning insulator according to claim 1, wherein a seal ring is interposed between the non-linear resistance element and the spacer to prevent the rubber mold from entering between them. 5. A tension insulating rod is passed through the center hole of a vertically elongated cylindrical non-linear resistance element group in which cylindrical non-linear resistance elements are connected in series, and grip fittings are attached to the upper and lower ends of the tension insulating rod, respectively. connect,
An annular spacer provided with an injection/pressure release path communicating between the inside and outside of the non-linear resistance element group is interposed in the connection portion of the non-linear resistance element group, and the gripping fitting is provided on the outer periphery of the non-linear resistance element group. A tension insulating cylinder having a large number of injection/pressure release holes approximately evenly spaced with some gaps is arranged on the outer circumferential surface of the non-linear resistance element group, and the tension insulating rod, the non-linear resistance element group, and a spacer are integrally enclosed by a rubber mold, and further, arcing rings are provided on each of the gripping metal fittings.