JP3603162B2

JP3603162B2 - Bare wire insulation cover and insulation structure

Info

Publication number: JP3603162B2
Application number: JP2002036238A
Authority: JP
Inventors: 滋宏津田; 秀樹齊藤
Original assignee: Sumiden Transmission and Distribution Systems Products Corp
Current assignee: Sumiden Transmission and Distribution Systems Products Corp
Priority date: 2002-02-14
Filing date: 2002-02-14
Publication date: 2004-12-22
Anticipated expiration: 2022-02-14
Also published as: JP2003244829A

Description

【０００１】
【発明の属する技術分野】
本発明は、ジャンパー線など、裸線の絶縁カバーと裸線の絶縁構造に関するものである。特に、鳥・樹木などの接触による地絡事故を防止することができる裸線の絶縁カバーに関するものである。
【０００２】
【従来の技術】
一般に、架空送電線のジャンパー装置は、図５に示すように、鉄塔３１からアーム材３２を伸ばし、このアーム材３２の端部に碍子３と引留めクランプ２を介して本線４が架設されている。そして、ジャンパー線１は碍子５に吊設されると共に、供給側と需要側の両方の本線４をつなぐように設けられている。この本線４およびジャンパー線１は、鋼心アルミ撚線（ＡＣＳＲ）や硬銅撚線（ＨＤＣＣ）などが用いられ、通常、絶縁被覆がされない裸電線である。そのため、カラスなどの鳥がジャンパー線１に止まって翼を広げた際、鉄塔３１のアーム材３２に触れることや、営巣材として針金などをくわえてアーム材３２に止まった際、針金の先がジャンパー線１に触れることで地絡事故が起こることがある。この対策として、アーム材３２やジャンパー線１に絶縁カバーを被せて被覆を施すことが行われている。
【０００３】
この絶縁カバーの一例を図３に示す。この絶縁カバー２０は渦巻き状の巻き癖をもったシート状のもので、その内面に渦巻きの軸方向に伸びる突条２１を具えている。この絶縁カバー２０は、巻き癖を開いてジャンパー線の外周に巻き付けて使用される。絶縁カバーの材質には絶縁性に優れるエチレンプロピレンゴムが用いられている。絶縁カバー内面に設けられた半円状の突条により、ジャンパー線の径方向への沿面距離をかせぐことができる。
【０００４】
一般にジャンパー線は垂れ下がった状態に鉄塔から支持されているため、このような屈曲部に上記の絶縁カバー２０を用いる場合、図４に示すように、ある程度の長さの絶縁カバー２０を複数並列してジャンパー線１の外周を覆う。そして、絶縁カバー２０のつなぎ目はジョイントカバー２２で覆うと共に、ジャンパー線沿いの複数個所を離散的に締付バンド２３で止めることによりカバーの固定を行っている。
【０００５】
【発明が解決しようとする課題】
しかし、上記の絶縁カバーには、次のような問題があった。
▲１▼ジャンパー線への取り付け・取り外しが行い難い。
渦巻き状の巻き癖が設けられていると、ジャンパー線への装着時、一旦巻き癖を最内周の巻き始めまで解かなければならず、装着作業が面倒である。もちろん、経時劣化や損傷などのため絶縁カバーを取り替える際にも巻き癖を解く必要があり、やはり作業性に欠けると言う問題がある。
【０００６】
▲２▼ジャンパー線の屈曲に沿って絶縁カバーの装着が行い難い。
上記のように、従来の絶縁カバーの形状は何重にも巻かれた渦巻き状になっているため屈曲性に乏しく、屈曲したジャンパ線の全長を単一の絶縁カバーで覆うことが非常に難しい。そのため、複数の絶縁カバーを用いなければならない上、ジョイントカバーも必要となり、部品点数の増大、取り付け作業の煩雑化の要因となっていた。
【０００７】
▲３▼ジャンパー線への装着時の外径が大きくなり、風圧荷重も大きくなる。
ジャンパー線の径方向への沿面距離をかせぐために、カバー内面に突条が設けられている。その結果、絶縁カバー装着時の外径が大きくなり、絶縁カバーで覆ったジャンパー線の風圧荷重が非常に大きくなってしまうと言う問題が生じる。
【０００８】
従って、本発明の主目的は、鳥・樹木などの接触による地絡事故を防止でき、取り付け・取り外しが容易にできる裸線の絶縁カバーを提供することにある。
【０００９】
本発明の他の目的は、裸線の屈曲に沿って装着ができる裸線の絶縁カバーを提供することにある。
【００１０】
また、本発明の他の目的は、絶縁カバー装着時の外径を極力小さくできる裸線の絶縁カバーを提供することにある。
【００１１】
さらに、本発明の別の目的は、鳥・樹木などの接触による地絡事故を防止でき、着脱が容易な裸線の絶縁構造を提供することにある。
【００１２】
【課題を解決するための手段】
本発明は、絶縁カバーの形状に工夫を施すことで上記の目的を達成する。
【００１３】
すなわち、本発明裸線の絶縁カバーは、裸線の外周を覆う絶縁カバーであって、この絶縁カバーは長尺のシート状で、その両側縁には裸線の外径よりも小さい径の巻き癖が設けられ、前記巻き癖を開いた際、裸線の外周に前記絶縁カバーを渦巻き状に装着できるような復元力が得られる弾性材で構成されたことを特徴とする。
【００１４】
従来の渦巻き状の絶縁カバーでは、取り付け・取り外し作業性に欠けることは既に述べた。本発明では、長尺のシート状の絶縁カバーにおいて、幅方向の両側縁に円弧状の巻き癖を設け、中間部は裸線の外径よりも大きい径の円弧または実質的に直線状に構成している。この構成により、カバー両側縁の巻き癖は渦巻き状のように何重にも重なっているわけではなく、比較的容易に巻き癖を解くことができる。また、絶縁カバーの幅方向中間部は実質的に開かれているため、この開口部から容易に裸線へのはめ込みを行うことができる。
【００１５】
この絶縁カバーの材質は、ＪＩＳＫ６３０１「加硫ゴム物理試験方法」のスプリング式硬さ試験（Ａ型）で測定した値が７５°以下のものが好適である。特に、６５°以下、さらには５５°以下が一層好ましい。もちろん、４５°以下の低硬度材料でも利用できる。硬度の高い材料を用いたときは絶縁カバーの厚みを薄くすれば良く、硬度の低い材料を用いた場合は同厚みを厚くしても良い。より具体的には、フッ素ゴム、シリコーンゴム、ウレタンゴム、エチレンプロピレンゴム、クロロプレンゴムの少なくとも１種が挙げられる。特に、耐熱性や電気絶縁性の点でシリコーンゴム、フッ素ゴムが好ましい。これらのゴムであれば可撓性に富み、容易に巻き癖を解くことができると共に、屈曲した裸線に沿って絶縁カバーを装着することができる。従って、複数の絶縁カバーを裸線の長手方向に並列して装着する必要がなく、ジョイントカバーも不要となる。なお、裸線の屈曲径が小さい場合、複数の絶縁カバーを並列して用いても良いことは言うまでもない。
【００１６】
この絶縁カバーは、裸線に巻き付けた際、要求される耐電圧特性を有する厚みが得られるような厚みを選択する。絶縁カバーの厚みとして、例えば、送電電圧７７ｋＶ（対地間電圧４４．５ｋＶ、対地間電圧：交流三相三線式の場合、線間電圧の１／√３）の裸電線に対しては、４．０ｍｍ〜８．０ｍｍ程度、特に好ましくは４．０ｍｍ程度の厚さが適する。送電電圧６６ｋＶ（対地間電圧３８．１ｋＶ）の裸電線に対しては、３．０ｍｍ〜６．０ｍｍ程度、特に好ましくは３．０ｍｍ程度の厚さが適する。
【００１７】
渦巻き状に巻き付けた絶縁カバーの重なり程度は、二重程度が好ましい。二重巻きで十分な絶縁特性が得られる程度の絶縁カバーの厚さを選択すれば、装着作業も行いやすく、外径もあまり大きくなることはない。ただし、巻き始めと巻き終わりの個所は３重に重なる。この３重の重なり部は、裸線の中心角９０°程度の範囲とすれば好適である。
【００１８】
また、カバーの両側縁はテーパ状に形成しておくことが好ましい。後述するように、この絶縁カバーは裸線への装着時、裸線の外周に渦巻き状に巻き付けて装着される。そのため、両側縁がテーパ状に形成されていれば、絶縁カバーの重複部で段差を生じにくく、裸線と絶縁カバーとの間に空隙が発生して絶縁特性が低下することも回避できる。
【００１９】
特に、カバー両側縁をテーパ形状とした場合、両側縁のテーパ形状が同一であることが望ましい。絶縁カバーが裸線に装着された場合、一方の側縁が径方向の内側（巻き始め）、他方の側縁が径方向の外側（巻き終わり）となる。両側縁のテーパ形状が同一であれば、巻き付け時に絶縁カバーの巻き付け向きを気にする必要は無く、いずれの側縁を巻き始めとしても同一形状の装着形状を得ることができる。
【００２０】
本発明絶縁カバーの被覆対象である裸線には、ジャンパー線や送電線本線があげられる。より具体的にはＡＣＳＲ、ＴＡＣＳＲ、ＧＳＴＡＣＳＲなどがあげられる。送電線本線に本発明カバーを適用する場合、本線が樹木や構造物などと接近している箇所に適用することが好ましい。
【００２１】
また、本発明裸線の絶縁構造は、上記裸線の絶縁カバーで裸線の外周を渦巻き状に被覆したことを特徴とする。この構成により、裸線の外周を確実に絶縁被覆することができ、鳥・樹木などの接触による地絡事故を防止することができる。
【００２２】
【発明の実施の形態】
以下、本発明の実施の形態を説明する。
図１は本発明絶縁カバーの部分斜視図、図２は本発明絶縁カバーでジャンパー線を覆った状態を示す断面図である。
【００２３】
この絶縁カバー１０は、図１に示すように、長尺のシート状のものであり、中間部１１がジャンパー線の外径よりも若干大きな径の円弧（または平面）で形成され、両側縁部１２にはジャンパー線の外径よりも小さい巻き癖が形成されている。この巻き癖は、装着性を考慮すると、数周重なって巻き込まれているものではなく、１．５周未満の巻き込み量であるものが好適である。より好ましくは１周未満の巻き込み量とする。両側縁の巻き癖の曲げ径サイズの一例としては、１８．２ｍｍφのＡＣＳＲ用絶縁カバーの場合、約１５ｍｍφである。
【００２４】
また、絶縁カバー１０の材料は、巻き癖を開いた際、ジャンパー線の外周に絶縁カバー１０を渦巻き状に装着できるような復元力を得るため、ＪＩＳＫ６３０１「加硫ゴム物理試験方法」のスプリング式硬さ試験（Ａ型）で測定したゴム硬度が約５５°のシリコーンゴムとした。シリコーンゴムは可撓性にすぐれ、容易に巻き癖を開くことができ、かつ屈曲したジャンパー線に沿って被覆を行うことができる。そして、両側縁部１２を除く絶縁カバー１０の厚みは、必要耐電圧特性が得られるように約３ｍｍとした。
【００２５】
絶縁カバーの両側縁部１２は、同一形状のテーパ状に形成されている。これは、両側縁がテーパ状に形成されていれば、絶縁カバーの重複部で段差を生じにくく、ジャンパー線と絶縁カバー１０との間に空隙が発生して絶縁特性が低下することを回避するためである。
【００２６】
本発明絶縁カバーで被覆を行う代表的なジャンパー線の種類、外径、断面積および絶縁カバーの幅との関係を表１に示す。表１において、「ＳＡＣＳＲ」は小サイズ鋼心アルミより線である。
【００２７】
【表１】

【００２８】
このような絶縁カバーは、図５に示すジャンパー装置のジャンパー線の外周に巻き付けて利用する。ここでは鋼芯の外周にアルミ線を撚り合わせたＡＣＳＲをジャンパー線としている。巻き付ける際、両側縁部１２の巻き癖を解き、中間部１１の内面をジャンパー線１に接触させ、一方の側縁をジャンパー線の外周に巻き付ける。さらに、他方の側縁で一方の側縁を覆うように絶縁カバー１０を巻き付け、ジャンパー線の全周を絶縁カバー１０で被覆する。被覆後のジャンパー線の断面図は、図２に示すように、ジャンパー線１の外周に絶縁カバー１０が渦巻き状に被覆された状態となる。ここでは、絶縁カバー１０が二重となるように巻き付けている。ただし、巻き始めと巻き終わりは三重に重ねて巻き付けられている。
【００２９】
また、長さ２ｍのジャンパー線のサンプルに半径１０ｍの屈曲を与え、そのジャンパー線に上記絶縁カバーの装着を行ったところ、容易に装着を行うことができ、かつ絶縁カバーは屈曲したジャンパー線に沿って装着されていた。
【００３０】
このような絶縁カバーによれば、容易にジャンパー線への着脱ができ、かつ屈曲したジャンパー線にも沿って被覆を形成することができる。また、長尺のジャンパー線の全長にわたって単一の絶縁カバーで被覆を形成でき、部品点数の減少と取り付け作業性の改善効果が極めて大きい。
【００３１】
【発明の効果】
以上説明したように本発明絶縁カバーおよび絶縁構造によれば、以下の効果を奏することができる。
【００３２】
▲１▼本発明絶縁カバーは高い絶縁性を具え、かつ施工性が極めてよい。
▲２▼本発明絶縁カバーは装着性に優れ、気候・温度などによって剥離しにくい。
▲３▼既存のジャンパー線などの裸線に後付けすることも容易にできる。
▲４▼従来の絶縁カバーに比較して施工後の径がはるかに小さくでき、風圧荷重の増加を低減することができる。
▲５▼裸電線の曲線的な弛みに沿って連続的に施すことが可能である。
【図面の簡単な説明】
【図１】本発明絶縁カバーの部分斜視図である。
【図２】本発明絶縁カバーでジャンパー線を覆った状態を示す断面図である。
【図３】従来の絶縁カバーの断面図である。
【図４】図３の絶縁カバーをジャンパー線に装着した状態の説明図である。
【図５】ジャンパー線を含む架空送電線を鉄塔に配置した状態を表す説明図である。
【符号の説明】
１ジャンパー線
２引留めクランプ
３碍子
４本線
５碍子
１０絶縁カバー
１１中間部
１２側縁部
２０絶縁カバー
２１突条
２２ジョイントカバー
２３締付バンド
３１鉄塔
３２アーム材[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a bare wire insulation cover such as a jumper wire and a bare wire insulation structure. In particular, the present invention relates to a bare wire insulation cover that can prevent a ground fault due to contact with a bird or a tree.
[0002]
[Prior art]
In general, as shown in FIG. 5, the jumper device for an overhead transmission line extends an arm member 32 from a tower 31, and a main line 4 is installed at an end of the arm member 32 via an insulator 3 and a retaining clamp 2. I have. The jumper wire 1 is suspended from the insulator 5 and provided so as to connect the main wires 4 on both the supply side and the demand side. The main wire 4 and the jumper wire 1 are made of a steel core aluminum stranded wire (ACSR), a hard copper stranded wire (HDCC), or the like, and are usually bare electric wires without insulation coating. Therefore, when a bird such as a crow stops on the jumper wire 1 and spreads its wings, when the bird touches the arm member 32 of the tower 31 or stops on the arm member 32 with a wire or the like as a nesting material, the tip of the wire Touching the jumper wire 1 may cause a ground fault. As a countermeasure, an arm cover 32 and a jumper wire 1 are covered with an insulating cover.
[0003]
FIG. 3 shows an example of this insulating cover. The insulating cover 20 is a sheet having a spiral curl, and has a ridge 21 extending in the axial direction of the spiral on its inner surface. This insulating cover 20 is used by opening the winding habit and winding it around the outer periphery of the jumper wire. As the material of the insulating cover, ethylene propylene rubber having excellent insulating properties is used. The semicircular ridge provided on the inner surface of the insulating cover can increase the creepage distance in the radial direction of the jumper wire.
[0004]
In general, since the jumper wire is supported from a steel tower in a hanging state, when the insulating cover 20 is used in such a bent portion, a plurality of insulating covers 20 having a certain length are arranged in parallel as shown in FIG. Cover the outer periphery of the jumper wire 1. The joint of the insulating cover 20 is covered with the joint cover 22, and the cover is fixed by discretely stopping at a plurality of locations along the jumper line with the tightening band 23.
[0005]
[Problems to be solved by the invention]
However, the above-mentioned insulating cover has the following problems.
(1) It is difficult to attach / detach to jumper wires.
If a spiral curl is provided, the curl has to be once unraveled to the beginning of the innermost winding when mounting on the jumper wire, and the mounting operation is troublesome. Of course, it is necessary to remove the curl even when replacing the insulating cover due to deterioration with time or damage, and there is a problem that workability is also lacking.
[0006]
(2) It is difficult to attach the insulating cover along the bending of the jumper wire.
As described above, the conventional insulating cover has a spiral shape with multiple windings, so it has poor flexibility, and it is very difficult to cover the entire length of the bent jumper wire with a single insulating cover. . For this reason, a plurality of insulating covers must be used, and a joint cover is also required, which increases the number of parts and complicates the mounting operation.
[0007]
(3) The outer diameter when mounted on the jumper wire increases, and the wind pressure load also increases.
A protrusion is provided on the inner surface of the cover to increase the creepage distance in the radial direction of the jumper wire. As a result, there arises a problem that the outer diameter when the insulating cover is attached becomes large, and the wind pressure load of the jumper wire covered with the insulating cover becomes extremely large.
[0008]
Accordingly, a main object of the present invention is to provide a bare wire insulating cover which can prevent a ground fault accident due to contact with a bird or a tree and can be easily attached and detached.
[0009]
It is another object of the present invention to provide a bare wire insulating cover that can be mounted along the bending of the bare wire.
[0010]
It is another object of the present invention to provide a bare wire insulating cover that can minimize the outer diameter when the insulating cover is attached.
[0011]
Still another object of the present invention is to provide a bare wire insulation structure which can prevent a ground fault accident due to contact with a bird or a tree and can be easily attached and detached.
[0012]
[Means for Solving the Problems]
The present invention achieves the above object by devising the shape of the insulating cover.
[0013]
That is, the bare wire insulation cover of the present invention is an insulation cover that covers the outer periphery of the bare wire, and the insulation cover is a long sheet-like shape, and has a smaller diameter than the outer diameter of the bare wire on both side edges. A habit is provided, and is formed of an elastic material capable of obtaining a restoring force such that the insulating cover can be spirally mounted on the outer periphery of the bare wire when the curl is opened.
[0014]
It has already been described that the conventional spiral insulating cover lacks the workability of attaching and detaching. According to the present invention, in the long sheet-shaped insulating cover, arc-shaped winding habits are provided on both side edges in the width direction, and the middle portion is formed into an arc having a diameter larger than the outer diameter of the bare wire or a substantially linear shape. are doing. With this configuration, the curl on both side edges of the cover does not overlap like a spiral, and the curl can be released relatively easily. In addition, since the widthwise middle portion of the insulating cover is substantially open, it is possible to easily fit the bare wire through the opening.
[0015]
As the material of the insulating cover, those having a value measured by a spring hardness test (A type) of JIS K 6301 “Vulcanized rubber physical test method” of 75 ° or less are preferable. In particular, it is more preferably 65 ° or less, further preferably 55 ° or less. Of course, a material having a low hardness of 45 ° or less can be used. When a material having a high hardness is used, the thickness of the insulating cover may be reduced, and when a material having a low hardness is used, the thickness may be increased. More specifically, at least one of fluorine rubber, silicone rubber, urethane rubber, ethylene propylene rubber, and chloroprene rubber is used. In particular, silicone rubber and fluorine rubber are preferable in terms of heat resistance and electrical insulation. With these rubbers, the rubber is rich in flexibility, the curl can be easily released, and the insulating cover can be attached along the bent bare wire. Therefore, it is not necessary to mount a plurality of insulating covers in parallel in the longitudinal direction of the bare wires, and a joint cover is not required. When the bending diameter of the bare wire is small, it goes without saying that a plurality of insulating covers may be used in parallel.
[0016]
The thickness of the insulating cover is selected so as to obtain a thickness having required withstand voltage characteristics when wound around a bare wire. As the thickness of the insulating cover, for example, for a bare electric wire having a transmission voltage of 77 kV (voltage to ground: 44.5 kV, voltage to ground: 1 / √3 of the line voltage in the case of an AC three-phase three-wire system), 4. A thickness of about 0 mm to 8.0 mm, particularly preferably about 4.0 mm is suitable. For a bare electric wire having a transmission voltage of 66 kV (voltage to ground: 38.1 kV), a thickness of about 3.0 mm to 6.0 mm, particularly preferably about 3.0 mm is suitable.
[0017]
The degree of overlap between the spirally wound insulating covers is preferably about double. If the thickness of the insulating cover is selected such that sufficient insulation characteristics can be obtained by double winding, mounting work is easy and the outer diameter does not become too large. However, the winding start and winding ends overlap three times. It is preferable that the three overlapping portions have a central angle of the bare line of about 90 °.
[0018]
Preferably, both side edges of the cover are formed in a tapered shape. As will be described later, when the insulating cover is attached to a bare wire, the insulating cover is wound around the bare wire in a spiral shape and attached. Therefore, if both side edges are formed in a tapered shape, a step is unlikely to occur at the overlapping portion of the insulating cover, and it is possible to avoid the occurrence of a gap between the bare wire and the insulating cover and the deterioration of the insulating characteristics.
[0019]
In particular, when both side edges of the cover are tapered, it is preferable that both side edges have the same tapered shape. When the insulating cover is attached to the bare wire, one side edge is radially inward (start of winding) and the other side edge is radially outward (end of winding). If the tapered shape of both side edges is the same, there is no need to worry about the winding direction of the insulating cover at the time of winding, and the same mounting shape can be obtained even when starting to wind either side edge.
[0020]
The bare wire to be covered by the insulating cover of the present invention includes a jumper wire and a transmission line. More specifically, there are ACSR, TACSR, GSTACSR and the like. When applying the cover of the present invention to a main line of a transmission line, it is preferable to apply the cover to a place where the main line is close to a tree or a structure.
[0021]
Further, the insulation structure of the bare wire according to the present invention is characterized in that the outer periphery of the bare wire is spirally covered with the insulation cover for the bare wire. With this configuration, the outer periphery of the bare wire can be reliably insulated and covered, and a ground fault due to contact with a bird or a tree can be prevented.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a partial perspective view of the insulating cover of the present invention, and FIG. 2 is a sectional view showing a state where a jumper wire is covered with the insulating cover of the present invention.
[0023]
As shown in FIG. 1, the insulating cover 10 is in the form of a long sheet, and the intermediate portion 11 is formed by an arc (or a plane) having a diameter slightly larger than the outer diameter of the jumper wire. 12, a winding habit smaller than the outer diameter of the jumper wire is formed. In consideration of the mountability, the winding habit is preferably not wound around several turns, but preferably has a winding amount of less than 1.5 turns. More preferably, the winding amount is less than one round. An example of the bending diameter size of the curl on both side edges is about 15 mmφ in the case of an ACSR insulating cover of 18.2 mmφ.
[0024]
Further, the material of the insulating cover 10 is JIS K 6301 “Physical Test Method for Vulcanized Rubber” in order to obtain a restoring force that allows the insulating cover 10 to be spirally mounted on the outer periphery of the jumper wire when the curl is opened. Silicone rubber having a rubber hardness of about 55 ° measured by a spring hardness test (A type) was used. Silicone rubber is excellent in flexibility, can easily open a curl, and can be coated along a bent jumper wire. The thickness of the insulating cover 10 excluding the side edges 12 was set to about 3 mm so as to obtain necessary withstand voltage characteristics.
[0025]
Both side edges 12 of the insulating cover are formed in a tapered shape having the same shape. This is because if the both side edges are formed in a tapered shape, a step is unlikely to occur at the overlapping portion of the insulating cover, and a gap between the jumper wire and the insulating cover 10 is prevented from deteriorating the insulating characteristics. That's why.
[0026]
Table 1 shows the relationship among the types, outer diameters, cross-sectional areas, and widths of typical jumper wires covered with the insulating cover of the present invention. In Table 1, "SACSR" is a small-sized steel core aluminum stranded wire.
[0027]
[Table 1]

[0028]
Such an insulating cover is used by being wound around the outer periphery of a jumper wire of the jumper device shown in FIG. Here, an ACSR in which an aluminum wire is twisted around the outer periphery of a steel core is used as a jumper wire. At the time of winding, the curl of the side edges 12 is released, the inner surface of the intermediate portion 11 is brought into contact with the jumper wire 1, and one side edge is wound around the outer periphery of the jumper wire. Further, the insulating cover 10 is wound so that the other side edge covers one side edge, and the entire circumference of the jumper wire is covered with the insulating cover 10. As shown in FIG. 2, the cross-sectional view of the jumper wire after the covering is such that the insulating cover 10 is spirally covered on the outer periphery of the jumper wire 1. Here, the insulating cover 10 is wound so as to be double. However, the winding start and the winding end are wound in three layers.
[0029]
In addition, when a sample of a jumper wire having a length of 2 m was bent with a radius of 10 m and the above-mentioned insulating cover was mounted on the jumper wire, the mounting could be easily performed, and the insulating cover could be attached to the bent jumper wire. Was fitted along.
[0030]
According to such an insulating cover, it is possible to easily attach / detach to / from the jumper wire and to form a coating along the bent jumper wire. In addition, the covering can be formed with a single insulating cover over the entire length of the long jumper wire, so that the number of parts is reduced and the mounting workability is greatly improved.
[0031]
【The invention's effect】
As described above, according to the insulating cover and the insulating structure of the present invention, the following effects can be obtained.
[0032]
{Circle around (1)} The insulating cover of the present invention has a high insulating property and has extremely good workability.
{Circle around (2)} The insulating cover of the present invention is excellent in mounting properties and is hard to peel off due to climate, temperature and the like.
(3) It can be easily attached to an existing bare wire such as a jumper wire.
{Circle over (4)} The diameter after construction can be made much smaller than that of a conventional insulating cover, and the increase in wind pressure load can be reduced.
{Circle around (5)} It is possible to apply the wire continuously along the curved slack of the bare wire.
[Brief description of the drawings]
FIG. 1 is a partial perspective view of the insulating cover of the present invention.
FIG. 2 is a cross-sectional view showing a state in which a jumper wire is covered by an insulating cover of the present invention.
FIG. 3 is a sectional view of a conventional insulating cover.
FIG. 4 is an explanatory view showing a state where the insulating cover of FIG. 3 is mounted on a jumper wire.
FIG. 5 is an explanatory diagram showing a state in which an overhead transmission line including a jumper wire is arranged on a steel tower.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 jumper wire 2 retaining clamp 3 insulator 4 main wire 5 insulator 10 insulating cover 11 intermediate portion 12 side edge 20 insulating cover 21 ridge 22 joint cover 23 fastening band 31 steel tower 32 arm material

Claims

An insulating cover for covering the outer periphery of the bare wire,
This insulation cover is a long sheet,
The central portion in the width direction is constituted by an arc or a substantially flat surface having a diameter larger than the outer diameter of the bare wire,
On both side edges of this central part, a winding habit of a diameter smaller than the outer diameter of the bare wire is formed less than 1.5 turns ,
An insulating cover for a bare wire, characterized in that it has a thickness having required withstand voltage characteristics when the winding cover is opened and the insulating cover is spirally mounted on the outer periphery of the bare wire.

The insulation of the bare wire according to claim 1, wherein the cover has a value measured by a spring-type hardness test (A type) of JIS K 6301 "Vulcanized rubber physical test method" of 75 ° or less. cover.

2. The bare wire insulating cover according to claim 1, wherein the cover is made of at least one of fluorine rubber, silicone rubber, urethane rubber, ethylene propylene rubber, and chloroprene rubber.

2. The bare wire insulating cover according to claim 1, wherein both side edges of the cover are formed in a tapered shape.

The insulated cover for bare wires according to claim 4, wherein the tapered shapes of the both side edges are the same.

An insulation structure for a bare wire, wherein the outer circumference of the bare wire is spirally covered with the insulation cover for a bare wire according to claim 1.