JPH0135443Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lightning arrester for low-voltage power distribution in which a fuse is inserted into non-linear resistance porcelain mainly made of zinc oxide.

Further, the lightning arrester according to the present invention is installed on a power distribution line, and when lightning current flows, it effectively discharges to the ground through the ground side terminal so as not to affect equipment on the side of the power distribution line.

Furthermore, the present invention is particularly capable of replacing lightning arresters for power distribution, which were conventionally formed by inserting a fuse into a combination of an arc-extinguishing gap and a characteristic element made of silicon carbide, with non-linear resistance porcelain mainly made of zinc oxide. This invention relates to the improvement of lightning arresters by utilizing their excellent nonlinearity and surge absorption characteristics.

In other words, this lightning arrester is used when the non-linear resistance porcelain is short-circuited due to an accident or deterioration.
A fuse is inserted to prevent high voltage from being applied to the distribution line side, causing accidents such as burning out the distribution line or blowing out the high-voltage fuse, and at the same time as the short circuit, the line side and the ground side are separated by the force of the spring, and the power is distributed. It protects between the lines.

When installing such a lightning arrester on a power distribution line for the first time, or when replacing one that has been damaged by a short circuit as mentioned above, it is desirable to be able to do it easily, as the work must be done at height, and it is important that there is little risk of electric shock. be.

However, the line-side connector to which the lightning arrester is attached is connected parallel to the line, and the surge arrester is also attached parallel to the distribution line, so when actually installing it, the connecting conductor between the lightning arrester and the connector must be bent. The work was dangerous because it took time and the risk of electric shock increased as the work had to be done while doing other things.

In view of these points, an object of the present invention is to provide a lightning arrester that can be installed and removed more easily and safely.

According to the present invention, this object is achieved in the lightning arrester by forming a threaded portion on the line side terminal and coupling the L-shaped connecting conductor with an insulating coating.

One embodiment will be described below with reference to the drawings.

FIG. 1 shows a lightning arrester according to the present invention, and FIG. 2 is a diagram showing this lightning arrester installed on a power distribution line. The main body of this lightning arrester 30 includes a non-linear resistance ceramic 1 mainly made of zinc oxide, which is held between a line side terminal copper plate 2 and a copper disk 4, and a resin ring 9 attached to the copper disk 4.
The ground side terminal boards 10 are installed facing each other via
A grounding conductor 3 is connected to the grounding terminal plate 10, and a conductive cap 7 is connected to the copper disc 4.
and are connected and held by a connecting body, which is a fuse 5. This fuse 5 is made of a rod-shaped or plate-shaped metal having a higher resistance value than copper, and one end is vertically fitted into the center hole 6 of the copper disk 4 and soldered thereto, and the other end is connected to the top of the cap 7. Part 8
Welded in. This cap 7 is received by the ground side terminal plate 10 at its skirt portion and is also electrically connected, so that it can be grounded through the ground side conductor 3.

The resin ring 9 is made of a resin material with good arc-extinguishing performance such as urea, melamine, or diuracon, and is interposed between the ground side terminal plate 10 and the copper disk 4 with an arc-extinguishing gap in between, thereby preventing the influence of arcs. I'm doing less. Furthermore, a spring 11 is provided inside the cap 7 fixed by the ground side terminal plate 10 and the fuse 5. When the fuse 5 or the solder 13 is blown, the elastic force of the spring 11 is compressed and the cap 7 is pushed outward. In addition to reducing the adverse effects of extrusion and arcing, by removing the cap 7 from the main body of the lightning arrester 30, melting of the fuse 5 or the solder 13 can be easily confirmed from the ground.

It is desirable to tie a shorting piece 12 such as copper foil to the spring 11 to short-circuit the ground side terminal plate 10 and the cap 7 to eliminate the influence of reactance due to the spring. The line-side terminal plate 2, the nonlinear resistance ceramic 1, and the copper disk 4 are formed of insulating resin 15 into a bell shape. The ground side terminal plate 10 is also connected to the ground side conductor 3 and is partially embedded in the insulating resin molding 15 so that the elastic force of the spring 11 can be maintained. An insulating cylinder 22 is fitted into the cap 7, and a string 20 is tied to prevent it from falling to the ground.

One end of an L-shaped conductor 16 bent into an L-shape in the middle is screwed into the top of the line-side terminal plate 2 on the opposite side to the surface in contact with the non-linear resistance ceramic 1 by means of a screw coupling means, and is screwed into the top part by a nut 19. Fixed.
The other end of this conductor 16 is connected to the distribution line L ₁ shown in FIG.
By simply screwing into the connector 50 with an insulating cover connected in parallel to L ₂ , L ₃ , and G and fixing it with a nut, a connection with excellent workability and safety can be achieved.

With this configuration, when an abnormal voltage such as a lightning current that exceeds the normal line-to-line lightning voltage occurs between the line and the ground, a part of the impact energy is converted into Joule heat in the nonlinear resistance ceramic 1. The remaining amount is discharged to the ground through the grounding conductor 3. However, if the non-linear resistance porcelain 1 is destroyed due to an accident or deterioration and causes a short circuit, it will have a serious effect on the equipment on the distribution line side, so the main body of the lightning arrester 30 must be replaced, but it is easy to do from the outside. Since this cannot be confirmed, a fuse is attached to the main body of the lightning arrester 30 as described above, and when the fuse 5 melts due to overcurrent during the short circuit, the cap 7 is separated by the force of the spring to prevent the adverse effects of the arc. At the same time, short-circuit destruction of the non-linear resistance ceramic 1 can be easily discovered.

This L-shaped conductor 16 is covered with an insulating rubber coating 17 except for the screw portion, but the L-shaped conductor 16 is also covered with an insulating rubber coating 17.
6 and the connection part of the lightning arrester 30 body with an insulating rubber cover 1
4 is desirable since it will be extremely favorable from the standpoint of work safety.

Rubber coating 17 of L-shaped conductor 16 and rubber cover 1
4 may be made of the same insulating material, and it is desirable that they overlap at the boundary 18 to ensure perfect insulation.

By doing the above, it is possible to obtain a lightning arrester that can be easily and safely installed and replaced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of a lightning arrester according to the present invention, and FIG. 2 is a diagram showing this lightning arrester installed on a power distribution line. 1...Non-linear resistance porcelain, 5...Fuse, 7...
... Cap, 11 ... Spring, 16 ... L-shaped connecting conductor, 14 ... Insulating rubber cover, 17 ... Insulating rubber coating.

Claims (1)

[Claims for Utility Model Registration] 1. A line side terminal is connected to one side of non-linear resistance porcelain mainly made of zinc oxide, a metal plate is installed on the other side to sandwich the non-linear resistance porcelain, and the metal plate A grounding side terminal is installed through an insulating resin so as to face each other with an arc extinguishing gap in between, and the non-linear resistance ceramic, line side terminal, metal plate and grounding side terminal are fixed together with an insulating resin, and the internal The spring end located on the opening side of the conductive cap-shaped body housing the spring is brought into contact with the ground side terminal, and the temperature between the top of the cap-shaped body and the metal plate is increased and The connecting body, each having a portion that melts and separates due to an overcurrent, is connected against the force of a spring housed inside the cap-shaped body, and the ground side terminal and the metal plate are connected by the connecting body, the spring, and the cap-shaped body. A line connector that is electrically connected through a body, and has a structure in which a spring and a cap-like body are separated from the ground side terminal when the connecting body is fused and separated, and is connected in parallel to a distribution line. 1. A lightning arrester for power distribution, characterized in that a threaded portion is formed on the line-side terminal, and an L-shaped connecting conductor with an insulating coating is coupled to the threaded portion of the line-side terminal. 2 Utility Model Registration Scope of Claims 1. The lightning arrester for power distribution, characterized in that a cover made of insulating rubber is provided at the connection portion between the L-shaped connecting conductor and the lightning arrester main body.