JP5390898B2 - Polymer lightning insulator - Google Patents

Description

  The present invention relates to a polymer lightning insulator in which an insulating rod member is provided on the outer peripheral portion of a laminated non-linear resistance element, for example, a zinc oxide element, both ends are fixed by a terminal metal fitting, and is covered with a polymer jacket. The present invention relates to a polymer lightning insulator with improved bending rigidity and improved explosion-proof performance.

Non-linear resistance elements (lightning protection elements) stacked inside a cylindrical insulator (cylindrical FRP), stacked at both ends with terminal fittings, and coated with a resin such as silicone rubber or EP rubber Lightning protection insulators are known.
In order to simplify the structure and facilitate assembly, an insulating rod member (FRP rod) is provided on the outer periphery of the non-linear resistance element (lightning protection element) instead of the FRP cylinder, and is covered with a polymer jacket. A polymer lightning insulator is known (see Patent Document 1).
The polymer lightning insulator is made of a rubber material, so that the mechanical strength is maintained mainly by an FRP rod or a cylindrical FRP which is an internal insulating member.
In particular, when fixing with a rod-like FRP, it is desired to make the FRP as thin as possible, but if it is made thin, sufficient rigidity cannot be obtained. Further, as shown in Patent Document 1, a method for improving rigidity using a metallic fixed spacer is also considered, but the explosion-proof performance is not sufficient.

JP 2002-151309 A

Polymer lightning insulators that use cylindrical insulators (cylindrical FRP) have had to be equipped with a pressure relief mechanism to release the internal pressure rise during pressure relief, and the structure and processing have become complicated. Since the polymer lightning insulator that shares the strength with FRP (FRP rod) does not need to be provided with a pressure release mechanism in particular, it is lighter and more compact than those using a cylindrical insulator. However, the bending rigidity is slightly weak, and the outer jacket is torn and released during explosion protection.
In order to improve the bending rigidity, it is conceivable to increase the size of the insulating rod member, but the weight increases or the size increases. Further, for example, as shown in Patent Document 1, it is conceivable to provide a reinforcing rib composed of a metal plate 5. However, in this configuration, since the metal plate 5 protrudes in the radial direction from the lightning protection element, there is a problem that the arc running on the surface of the lightning protection element passes through the metal plate 5 and the explosion-proof performance is lowered. That is, in order to improve the explosion-proof performance while improving the bending rigidity, it is not sufficient to simply include the reinforcing rib.
The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a polymer lightning insulator with improved explosion-proof performance while improving bending rigidity.

As a method of improving bending rigidity and improving explosion-proof performance without increasing the size of the insulating rod member that shares mechanical strength, a conductive member having a diameter not exceeding the zinc oxide element diameter between the non-linear resistance elements and the above A member made of an insulating rib having a diameter larger than the element diameter is provided.
That is, a conductive member for conductive passage (metal fixed spacer) is sandwiched between stacked nonlinear resistance elements, for example, zinc oxide elements. This conductive member (metal fixed spacer) has a diameter slightly smaller than (or does not exceed the element diameter) the element diameter.
Further, a rib made of an insulating material and having a diameter larger than that of the element is provided on the outer peripheral side of the spacer, a through hole is provided in the rib, the insulating rod member is passed through, and the rib is sandwiched by the element or the spacer. Fix with the compression force of.

By comprising in this way, compared with the conventional no rib, bending rigidity can be improved, without enlarging the conventional insulation rod member. In addition, the metal spacer does not protrude to the outer peripheral side of the element, and the rib is formed of an insulating material, so that the arc path generated on the surface of the metallic spacer in contact with the element can be interrupted. It is compact, and the explosion-proof performance can be improved.
The metal fixing spacer may be composed of a plurality of members, and the spacer may be fixed with the rib made of the insulating material sandwiched between the ribs made of the insulating material and the metal fixing spacer. You may use the composite integrally molded rib integrally molded.
Furthermore, when a plurality of spacers are used, electrical contact can be improved by sandwiching a conductive sheet between the spacers.

Polymer lightning insulators that share the strength with insulating rod members do not require a special pressure release mechanism to release the internal pressure rise during pressure release, and the structure is such that the jacket is broken, and the productivity is good. However, although it depends on the shape and design, the bending rigidity is slightly weak.
In the present invention, an insulation having a metal fixed spacer having a diameter not exceeding the diameter of the non-linear resistance element and a through-hole having a diameter larger than the non-linear resistance element diameter and through which the insulating rod member passes is provided. Since a member composed of a cylindrical rib is inserted, the bending rigidity can be improved and the extension of the arc generated on the metallic rib surface in contact with the element during pressure release can be suppressed. A polymer lightning arrester with excellent performance can be obtained.

It is a figure which shows the structure of the polymer lightning arrester of the Example of this invention. It is a figure which shows the structural example of metal fixing spacers and insulating ribs. It is a figure which shows an example of the attachment space | interval of an insulating rib. It is a figure which shows the example of arrangement | positioning of the insulation rib when one end is fixed and a bending load is added to the other.

FIG. 1 is a diagram showing the structure of a polymer lightning insulator according to an embodiment of the present invention, in which FIG. 1 (a) is a cross-sectional view taken along a plane passing through the central axis in the longitudinal direction, and FIG. A-A cross-sectional view of (), (c-1), (c-1) is a configuration example of parts of the rib portion.
In the figure, a non-linear resistance element 6 (for example, a zinc oxide element) laminated with a spring 2 and a metal spacer 7 are disposed between the end unmetals 1a and 1b, and both ends are located on the outer peripheral side of the end fitting part 1a. , 1b are provided, and the whole is molded with a jacket rubber 8 such as silicone rubber.
The insulating rod member 3 is, for example, a glass fiber, a polyester fiber, a polyamide fiber, a Kevlar fiber or the like crosslinked with an insulating organic material such as an epoxy resin, a polyethylene resin, or a polyester resin, and serves as a strength sharing material for a polymer lightning insulator. It is used.

The insulating rod member 3 sharing these strengths is fastened so as to surround the non-linear resistance element 6 with the end fittings 1a and 1b. In this embodiment, the insulating bar member 3 is interposed between the non-linear resistance elements 6. The metal fixed spacer 5 made of metal (for example, aluminum, copper, iron, etc.) and having a diameter slightly smaller than the diameter of the non-linear resistance element 6 (or not exceeding the element diameter), and insulation larger in diameter than the element diameter (For example, FRP, epoxy, bakelite, etc.) cylindrical insulating ribs 4 are provided. The insulating ribs 4 are formed by the metal fixing spacer 5 or the metal fixing spacer 5 and the non-linear resistance element 6. It is pinched and fixed by.
For example, as shown in FIG. 1C-1, the insulating rib 4 has a disk shape in which an annular hole 41 is provided in the center portion, and a through hole 42 through which the insulating rod member 3 passes is provided. It has been. The metal fixing spacer 5 includes first and second spacers 5a and 5b made of metal. The metal fixing spacers 5a and 5b are provided at the center of the disc-shaped insulating rib 4. A convex portion 51 that enters the inner diameter of the hole 41 is provided.

The insulating rib 4 and the first and second spacers 5a and 5b made of metal are formed in the hole 41 provided in the central portion of the disc-shaped insulating rib 4 as shown in FIG. The metal spacers 5a and 5b are inserted between the non-linear resistance elements 6 in a state in which the convex portions 51 are fitted. The surfaces of the metal spacers 5a and 5b on the convex portion 51 side are in contact with each other to maintain conductivity, and the surfaces on the back surface side of the convex portion 51 are in contact with non-linear resistance elements.
Further, as shown in FIG. 1B, the insulating rod member 3 having both ends fixed by the terminal metal fittings 1a and 1b penetrates through the through holes 42 provided in the insulating rib 4.

In this manner, a member constituted by the metal fixed spacer 5 smaller than the diameter of the element 6 and the cylindrical insulating rib 4 having a diameter larger than the diameter of the element 6 is inserted between the non-linear resistance elements 6. Since the insulating rod member 3 is passed through the through hole of the insulating rib 4, the bending rigidity can be improved, the extension of the arc generated on the surface of the metal spacer can be suppressed, and the explosion-proof performance can be improved. .
In order to further improve the explosion-proof performance, the outer peripheral surface of the metallic fixed spacer 5 (the surface not in contact with the non-linear resistance element 6 or other metallic fixed spacer) may be coated with an insulating material such as glass or epoxy. Good. Thereby, the extension of the arc generated on the surface can be suppressed and the characteristics can be improved.

FIG. 2 shows a configuration example of the metal fixing spacer 5 and the insulating rib 4. This figure is a cross-sectional view taken along a plane passing through the central axis.
FIG. 4A shows an example in which a cylindrical insulating rib 4 and a single metal fixing spacer 5 are combined. The conductive metal fixing spacer 5 is connected to the inner side of the cylinder of the insulating cylindrical rib 4. A conductive convex portion 51 that enters the inner diameter of the hole 41 is provided, and the convex portion 51 is fitted into a hole inside the insulating cylindrical rib 4 and inserted between the non-linear resistance elements 6. .
The surface on the convex portion 51 side is in contact with one non-linear resistance element 6, the surface on the back side of the convex portion 51 is in contact with the other non-linear resistance element 6, and the non-linear resistance element 6 is The conductive spacers 5 are stacked while maintaining electrical conductivity through the metal fixed spacers 5.
In this case, the contact area of the end face of the non-linear resistance element 6 becomes small and the current density of the element becomes high, so that there is a problem that the element is damaged.

In order to solve this problem, as shown in FIG. 2B, the insulating rib 4 and the three metal fixing spacers 5 are combined, and the first metal made into the inner diameter of the cylinder of the insulating cylindrical rib 4 is used. The fixing spacer 5b is fitted into the inner hole of the insulating cylindrical rib 4, and the insulating rib 4 is fixed by the second and third metal fixing spacers 5a and 5c so as to come into contact with both surfaces of the metal fixing spacer 5b. And the first metal fixed spacer 5b may be sandwiched.
In this case, there is a problem that the number of parts is increased and the metal fixing spacers 5a to 5c and the rib 4 are easily displaced from the center.
Further, as shown in FIG. 2 (c), the convex portion 51 of the first metal fixing spacer 5a is fitted into the hole 41 inside the cylinder of the insulating rib 4, and the disc-shaped second metal. A configuration is also conceivable in which the fixed spacer 5b is overlapped so as to contact the surface of the first metal fixed spacer 5a on the convex portion 51 side. Also in this case, there are problems that the number of parts increases and misalignment is likely to occur as described above.

In order to solve the problem that the misalignment is likely to occur, as shown in FIG. 1, the structure is sandwiched between the two convex metal fixing spacers 5a and 5b that enter the inner diameter of the cylindrical insulating rib 4. However, in order to improve the contact between the convex metal fixed spacers 5a and 5b and the contact with the element 6, as shown in FIG. It is desirable to put between. Examples of the conductive sheet 9 include soft metals such as lead, gold, silver, copper, tin, metal foil, and conductive resin sheets.
That is, as shown in (d-2), the conductive sheet 9 is inserted between the metal fixed spacers 5a and 5b, and the insulating rib 4 is sandwiched between the metal fixed spacers 5a and 5b from above and below. Thereby, contact resistance can be reduced.
Furthermore, it is also conceivable that the metal spacer 5 and the cylindrical insulating rib 4 are integrally formed to have a shape as shown in FIGS. In this case, there is a problem that the number of parts is reduced but the cost is increased.

Here, as shown in FIG. 3, the insulating ribs 4 may be inserted, for example, at intervals of 60 mm or more between the non-linear resistance elements 6, but if they are attached at a very short interval, there is a problem in productivity, preferably 200 About 1 piece should be arranged at intervals of ~ 500 mm.
Also, for example, when one end of a polymer lightning insulator is fixed and a bending load is applied to the other, as shown in FIG. Can also be improved. In particular, when the load is not unidirectional, it is preferable that the insulating ribs 4 are evenly arranged.

DESCRIPTION OF SYMBOLS 1a, 1b Terminal metal fitting 2 Spring 3 Insulating rod member 4 Insulating rib 5 Metal fixing spacer 6 Nonlinear resistance element 7 Metal spacer 8 Jacket rubber 9 Conductive sheet

Claims (3)

In the polymer lightning insulator, which is provided with an insulating rod member on the outer peripheral portion of the laminated non-linear resistance element, both ends thereof are fixed with terminal fittings, and covered with a polymer jacket,
Between the non-linear resistance elements, a metal fixed spacer having a diameter not exceeding the diameter of the element, and an insulating cylindrical rib having a through hole larger than the non-linear resistance element diameter and through which the insulating rod member passes. A polymer lightning insulator characterized by inserting a member to be configured and allowing the insulating rod member to penetrate the through hole. 2. The polymer lightning insulator according to claim 1, wherein the metal fixing spacer includes a plurality of members, and the spacer is fixed with the rib made of the insulating material interposed therebetween.   The polymer lightning insulator according to claim 2, wherein a soft conductive sheet is sandwiched between the plurality of spacers.

Images