JPH06275140A - Tree-proof insulated wire - Google Patents

Abstract

PURPOSE:To detect the degree of damage caused by contact between an insulated wire and trees by providing a damage detection layer of the color phase different from that of an abrasion-proof layer, on the inner circumferential part or on the intermediate part of the abrasion-proof layer on the outside of a main insulator layer. CONSTITUTION:A damage detection layer of the color phase which is different from that of an abrasion-proof layer is provided on the inner circumferential part or on the intermediate part of the abrasion-proof layer provided on the outside of a main insulator layer, to provide a tree-proof insulated electric wire. For example, a conductor 1, a main insulator layer (ex. polyethylene) 2, a damage detection layer (ex. high density polyethylene) 3, and an abrasion- proof layer 4 are provided in this order. For the abrasion-proof layer 4, black high density polyethylne, high desity crosslinked-polyethylene and the like are used in consideration of the contact between the layer and a tree. In this structure, when the damage detection layer 3 and the abrasion-proof layer 4 are formed of the same material except for the color phase, since the abrasion-proof property is maintained even when the damage detection layer 3 is exposed, no damage is given to the main insulator layer 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tree-resistant insulated wire capable of detecting damage caused by contact of an overhead distribution line with a tree.

[0002]

2. Description of the Related Art Overhead distribution lines installed near trees are
In contact with trees, the insulator may be scraped off by vibration due to wind, etc., resulting in a ground fault through the trees and a power failure. For this reason, conventionally, grown trees have been cut so that they do not come into contact with electric wires, or electric poles have been relocated to prevent them from contacting.

[0003]

However, cutting the grown trees not only costs a lot of money, but also leads to environmental damage, and there is a problem that it is difficult to move utility poles due to soaring land prices.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and provides a tree-resistant insulated wire capable of detecting the degree of damage due to contact of the insulated wire with a tree.
This is because a damage detection layer having a hue different from that of the wear resistant layer is provided on the inner peripheral portion or the middle portion of the wear resistant layer provided outside the main insulator layer.

[0005]

In the above tree-resistant insulated wire of the present invention,
Even if the wire contacts the tree and damages the wear-resistant layer, the damage detection layer with a different hue from the wear-resistant layer is exposed before the quality of the wire falls below the required quality, and the damage level of the wire can be detected. , It is possible to determine the appropriate replacement time.

[0006]

EXAMPLE FIG. 1 is a cross-sectional view of a specific example of the tree-resistant insulated wire of the present invention. In the drawings, 1 is a conductor, 2 is a main insulator layer such as polyethylene or cross-linked polyethylene, and 3 is a damage detection layer such as high-density polyethylene or high-density cross-linked polyethylene, and has a hue different from that of the wear-resistant layer 4 applied thereon. Have. 4 is a wear-resistant layer applied on the damage detection layer 3, and in consideration of contact with trees, black high-density polyethylene, high-density cross-linked polyethylene, etc. having excellent damage resistance, wear resistance, and tracking resistance are used. used.

In the above structure, when the damage detection layer 3 is formed of the same material as the wear resistant layer 4 except for the hue,
Even if the damage detection layer 3 is exposed, the main insulator layer 2 is not damaged because it has abrasion resistance.

FIG. 2 is a cross-sectional view of another embodiment of the tree-resistant insulated wire of the present invention. In the drawing, the same reference numerals as those in FIG. 1 represent the same parts. In this example, the damage detection layer 3 is provided in the middle portion of the wear resistant layer 4, and the wear resistant layer 4 ′ also exists inside the damage detection layer 3. In this structure, since the abrasion-resistant layer 4 ′ also exists inside the damage-detecting layer 3, the damage-detecting layer 3 does not particularly require abrasion resistance, and if only the hue differs from the abrasion-resistant layer 4, the material May use tape or the like.

[0009]

As described above, according to the tree-resistant insulated electric wire of the present invention, even if the outermost wear-resistant layer is damaged due to the electric wire coming into contact with the tree, the quality of the electric wire does not fall below the required quality. By exposing the damage detection layers having different hues, it is possible to detect the damage degree of the electric wire, and it is possible to replace the wire at an appropriate time.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a specific example of a tree-resistant insulated wire of the present invention.

FIG. 2 is a cross-sectional view of another specific example of the tree-resistant insulated wire of the present invention.

[Explanation of symbols]

 1 conductor 2 main insulator layer 3 damage detection layer 4 wear-resistant layer 4'inner layer wear-resistant layer

Front page continuation (72) Inventor Junji Taniguchi 3-3-22 Nakanoshima, Kita-ku, Osaka City Kansai Electric Power Co., Inc. (72) Inventor Ichiro Kitamura 3-3-22 Nakanoshima, Kita-ku, Osaka City Kansai Electric Power Co. In-house (72) Inventor Fumihiko Yoshimura 1-3-3 Shimaya, Konohana-ku, Osaka City Sumitomo Electric Industries, Ltd. Osaka Works (72) Inventor Michio Uchino 1-3-3 Shimaya, Konohana-ku, Osaka City Sumitomo Denki Industry Co., Ltd.Osaka Works

Claims (1)

[Claims] 1. A tree-resistant insulated wire, characterized in that a damage detection layer having a hue different from that of the wear-resistant layer is provided on an inner peripheral portion or an intermediate portion of the wear-resistant layer provided outside the main insulating layer.