JP4028091B2

JP4028091B2 - Manufacturing method of electric wire with water stop

Info

Publication number: JP4028091B2
Application number: JP17437198A
Authority: JP
Inventors: 光吉田代
Original assignee: THE FURUKAW ELECTRIC CO., LTD.
Current assignee: THE FURUKAW ELECTRIC CO., LTD.
Priority date: 1998-06-22
Filing date: 1998-06-22
Publication date: 2007-12-26
Anticipated expiration: 2018-06-22
Also published as: JP2000011771A

Description

【０００１】
【発明の属する技術分野】
本発明は、例えば自動車のワイヤーハーネス等に用いられる止水部付き電線の製造方法に関するものである。
【０００２】
【従来の技術】
自動車のワイヤーハーネス等に用いられる電線は通常、複数本の素線を撚り合わせた撚線導体の外周に、熱可塑性樹脂の絶縁被覆を施した構成となっている。このような電線の場合、撚線導体の素線の間や、撚線導体と絶縁被覆の間に隙間があるため、雨水などがかかると、電線端部の端子取り付け部や中間部の分岐接続部などから電線内に水が浸入することがある。電線内に浸入した水は、上記の隙間を通って電線長さ方向に伝わって、いわゆる水走り現象をおこし、広範囲にわたって撚線導体や端子部品を腐食させたり、接触不良を生じさせたりする原因となる。
【０００３】
そこで電線内の水走りを防止するために、撚線導体の外周に長さ方向に間欠的に止水材を配した上で絶縁被覆を施した止水機能付きの電線が提案されている（特開平９−３３０６２２号公報）。この電線は、内部に水が浸入すると、前記止水材が水を吸収して膨張し、電線内部の隙間を塞ぐことにより、水走りを防止するものである。
【０００４】
この電線の場合、止水材を配した部分は、絶縁被覆を剥いでも止水材が残っていて導体が完全に露出しないので、端子の取り付けなどの電気的接続を行うことは好ましくない。このため絶縁被覆の表面に、止水材を配した位置に対応する印をつけておき、止水材のある位置では絶縁被覆の剥ぎ取りを行わないようにしている。
【０００５】
【発明が解決しようとする課題】
従来提案されている止水機能付き電線は、撚線導体の外周に付着させた止水材を水で膨張させて電線内の隙間を埋めようとするものであるが、このような構造では、止水材が電線の長さ方向あるいは径方向に膨張してしまい、膨張した止水材が必ずしも撚線導体内の素線間の隙間に入り込むとは限らないので、撚線導体内の素線間の隙間が通水路として残る可能性があり、止水効果が不十分である。
またこの電線を製造するには、撚線導体上に絶縁被覆を押出被覆する工程で、導体に止水材を付着させる作業と、絶縁被覆に印を付ける作業を行わなければならないため、製造が面倒である。また押出速度が低くなるため、生産効率が低下するという問題がある。
【０００６】
本発明の目的は、上記のような問題点に鑑み、止水効果が確実で、製造も容易な止水部付き電線の製造方法を提供することにある。
【０００７】
削除
【０００８】
削除
【０００９】
【課題を解決するための手段】
本発明に係る止水部付き電線の製造方法は、撚線導体の外周に熱可塑性樹脂よりなる絶縁被覆を施した電線を用意し、この電線の絶縁被覆を適当な長さ毎に切断すると共に絶縁被覆の切断面間に間隔をあけ、これによって撚線導体が露出したところに液状の止水用樹脂を供給して、液状の止水用樹脂で撚線導体の外周面を覆うと共に撚線導体の素線間の隙間を埋め、その後、絶縁被覆の切断面の間隔を狭めることにより撚線導体の外周面に付着していた止水用樹脂を絶縁被覆の切断面ではさみつけ、その状態で止水用樹脂を固化させると共に絶縁被覆の切断面に接着させることを特徴とするものである。
【００１０】
なおこの製造方法において、止水用樹脂を供給するときは、絶縁被覆の切断面間に間隔をあけた区間で、撚線導体の撚りを弛ませて素線間の隙間を広げるようにすると、素線間の隙間に、より確実に止水用樹脂を充填することができる。
【００１１】
【発明の実施の形態】
以下、本発明の実施形態を図面を参照して詳細に説明する。
図１（ａ）〜（ｃ）は本発明の製造方法により製造された止水部付き電線の一例を示す。図において１は複数本の銅またはアルミ素線１ｓを撚り合わせた撚線導体、２はその上に押出被覆された熱可塑性樹脂よりなる絶縁被覆である。
【００１２】
この電線では、撚線導体１は長さ方向に連続しているが、絶縁被覆２は適当な長さ毎に切断されて長さ方向に不連続になっている。絶縁被覆２が切断された箇所では、撚線導体１の素線１ｓ間の隙間、撚線導体１の外周面および絶縁被覆２の切断面間の隙間が止水用樹脂３で埋められ、止水部を構成している。また止水用樹脂３は絶縁被覆２の切断面に接着している。止水用樹脂３としては、絶縁被覆２と接着性のある熱可塑性樹脂または熱硬化性樹脂が使用される。
【００１３】
この止水部付き電線は上記のように、長さ方向に適当な間隔をおいて、撚線導体１の素線１ｓ間の隙間、撚線導体１の外周面および絶縁被覆２の切断面の間を埋める止水用樹脂３によって止水部が形成されているため、電線端部または中間部の絶縁被覆２が剥ぎ取られた部分から水が浸入したとしても、その近くの止水部によって水走りが阻止され、障害が広範囲に広がることがない。
【００１４】
またこの止水部付き電線の外観は、適当な長さ毎に切断された絶縁被覆２が止水用樹脂３によって接続された形態となっているため、止水部とそうでない部分との区別がはっきりしており、端子などを接続するときは、止水部を避けて絶縁被覆２の剥ぎ取りを行うことにより、確実な電気的接続を行うことができる。
【００１５】
なお止水部とそうでない部分との区別をより明確にするためには、図１に示すように止水用樹脂３の外径を絶縁被覆２の外径より大きくして、止水部を竹の節のようにするとか、止水用樹脂３の色を絶縁被覆２の色と異ならせるようにするとよい。
【００１６】
次に本発明に係る止水部付き電線の製造方法の一実施形態を図２（ａ）〜（ｄ）を参照して説明する。
この製造方法では、まず図２（ａ）に示すように、撚線導体１に熱可塑性樹脂よりなる絶縁被覆２を施した電線４を用意する。この電線４は通常の押出被覆工程で高速で製造することができる。この電線４を長さ方向に間欠的に走行させ、走行が停止したときに、定位置に設置されている切り込み刃５で、（ｂ）のように絶縁被覆２に切り込みを入れると共に、その両側の絶縁被覆２を第一のチャック６Ａと第二のチャック６Ｂでそれぞれ把持する。切り込み刃５は、撚線導体１に傷をつけないように、撚線導体１の外径より若干大きい内径の半円形の刃形に形成されている。またチャック６Ａ、６Ｂは把持した絶縁被覆２がずれないように、内周面に凹凸をつけておくとよい。
【００１７】
次に第一のチャック６Ａをその位置に固定したまま、切り込み刃５と第二のチャック６Ｂを第一のチャック６Ａから離れる方向に移動させ、（ｃ）に示すように絶縁被覆２の切断面間に間隔をおける。これによって撚線導体１が露出するから、この状態でノズル７から液状の止水用樹脂３ｅを供給し、止水用樹脂３ｅで撚線導体１の外周面を覆うと共に、撚線導体の素線１ｓ間の隙間を埋める。撚線導体１内の素線１ｓ間の隙間に止水用樹脂３ｅを十分に入り込ませるためには、第一のチャック６Ａまたは第二のチャック６Ｂを撚線導体１の撚りが弛む方向に回転させて、各素線１ｓ間の隙間を広げるようにするとよい。なお第一のチャック６Ａまたは第二のチャック６Ｂを撚線導体１の撚りが弛む方向に回転させたときは、その後に逆方向に回転させて元の状態にもどす。
【００１８】
次に、ノズル７および切り込み刃５を後退させた後、（ｄ）に示すように第二のチャック６Ｂを第一のチャック６Ａに接近する方向に移動させ、撚線導体１の外周面に付着している止水用樹脂３ｅを、絶縁被覆２の切断面ではさみつける。ここまでの作業は液状の止水用樹脂３ｅが固化しないうちに行う。その後、第一のチャック６Ａと第二のチャック６Ｂを開放し、電線４を１ピッチだけ長さ方向に走行させると（ａ）の状態にもどる。絶縁被覆２の切断面ではさみつけられた止水用樹脂３ｅは時間の経過によって固化し、絶縁被覆２の切断面に接着する。このような工程を繰り返すことにより、図１のような止水部付き電線を製造することができる。
【００１９】
なお第二のチャック６Ｂを移動させる場合、絶縁被覆２をたるませた後の引き戻しを容易にするため、図３に示すように第二のチャック６Ｂから離れたところに移動しない第三のチャック６Ｃを設置しておいて、第二のチャック６Ｂと同時に開閉を行うようにするとよい。
また上記の実施形態では、切り込み刃の片側のチャックのみを電線の長さ方向に移動させたが、両側のチャックを移動させるようにすることもできる。
【００２０】
【発明の効果】
以上説明したように本発明によれば、適当長さ毎に絶縁被覆を切断し、そこに撚線導体の素線間の隙間、撚線導体の外周面および絶縁被覆の切断面間の隙間を埋めるように止水用樹脂をつめて止水部を形成しているため、止水効果の確実な止水部付き電線を製造することができる。また止水部は撚線導体に絶縁被覆を施して電線とした後に形成できるため、製造が容易であり、かつ絶縁被覆の押出速度を低下させることがないので、生産性も良好である。
【図面の簡単な説明】
【図１】本発明の製造方法により製造された止水部付き電線の一例を示すもので、（ａ）は一部切開側面図、（ｂ）は（ａ）のｂ−ｂ線断面図、（ｃ）は（ａ）のｃ−ｃ線断面図。
【図２】（ａ）〜（ｄ）は本発明に係る止水部付き電線の製造方法の一実施形態を示す一部切開側面図。
【図３】本発明に係る止水部付き電線の製造方法の他の実施形態を示す一部切開側面図。
【符号の説明】
１：撚線導体
１ｓ：素線
２：絶縁被覆
３：止水用樹脂
３ｅ：液状の止水用樹脂
４：電線
５：切り込み刃
６Ａ、６Ｂ：チャック
７：ノズル[0001]
BACKGROUND OF THE INVENTION
The present invention relates to, for example, production side of the water stopper with wire used for automobile wire harnesses, etc. method.
[0002]
[Prior art]
An electric wire used for an automobile wire harness or the like usually has a configuration in which an insulation coating of a thermoplastic resin is applied to the outer periphery of a stranded wire conductor obtained by twisting a plurality of strands. In the case of such electric wires, there is a gap between the strands of the stranded conductor or between the stranded conductor and the insulation coating. Water may enter the electric wire from some parts. The water that has penetrated into the electric wire travels in the length direction of the electric wire through the gaps, causing the so-called water running phenomenon, and corroding the stranded wire conductor and terminal parts over a wide range and causing poor contact It becomes.
[0003]
Therefore, in order to prevent water running in the electric wire, an electric wire with a water stopping function has been proposed in which an insulating coating is applied to the outer periphery of the stranded wire conductor after intermittently providing a water stopping material in the length direction ( JP-A-9-330622). In this electric wire, when water enters the inside, the water stop material absorbs the water and expands to close a gap inside the electric wire, thereby preventing water running.
[0004]
In the case of this electric wire, since the water stop material remains in the portion where the water stop material is disposed and the conductor is not completely exposed even if the insulation coating is peeled off, it is not preferable to perform electrical connection such as terminal attachment. For this reason, a mark corresponding to the position where the water blocking material is disposed is provided on the surface of the insulating coating so that the insulating coating is not peeled off at a position where the water blocking material is present.
[0005]
[Problems to be solved by the invention]
The conventionally proposed electric wire with a water stop function is to expand the water stop material attached to the outer periphery of the stranded conductor with water to fill the gap in the electric wire, but in such a structure, The waterproofing material expands in the length direction or radial direction of the electric wire, and the expanded waterproofing material does not necessarily enter the gap between the strands in the stranded wire conductor. The gap between them may remain as a water passage, and the water stop effect is insufficient.
In addition, in order to manufacture this electric wire, in the process of extrusion coating the insulation coating on the stranded conductor, it is necessary to perform a work of attaching a water stop material to the conductor and a work of marking the insulation coating. It is troublesome. Moreover, since extrusion speed becomes low, there exists a problem that production efficiency falls.
[0006]
SUMMARY OF THE INVENTION In view of the problems as described above, a reliable water stopping effect, also prepared to provide a preparation how easy water stopper with wire.
[0007]
Delete [0008]
Delete [0009]
[Means for Solving the Problems]
The method for producing an electric wire with a water stop according to the present invention prepares an electric wire having an insulation coating made of a thermoplastic resin on the outer periphery of a stranded wire conductor, and cuts the insulation coating of the electric wire every appropriate length. A space is provided between the cut surfaces of the insulation coating, whereby a liquid water-stopping resin is supplied to the exposed portion of the stranded wire conductor to cover the outer peripheral surface of the stranded wire conductor with the liquid water-stopping resin and the stranded wire. The gap between the conductor wires is filled, and then the gap between the cut surfaces of the insulation coating is narrowed so that the water-stopping resin adhering to the outer peripheral surface of the stranded wire conductor is sandwiched between the cut surfaces of the insulation coating. The water-stopping resin is solidified and adhered to the cut surface of the insulating coating.
[0010]
In this manufacturing method, when supplying the water-stopping resin, in a section where there is a gap between the cut surfaces of the insulation coating, the twist of the stranded conductor is loosened to widen the gap between the strands. It is possible to more reliably fill the gap between the strands with the water-stopping resin.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Fig.1 (a)-(c) shows an example of the electric wire with a water stop part manufactured by the manufacturing method of this invention. In the figure, 1 is a stranded wire conductor formed by twisting a plurality of copper or aluminum strands 1s, and 2 is an insulation coating made of a thermoplastic resin extrusion-coated thereon.
[0012]
In this electric wire, the stranded conductor 1 is continuous in the length direction, but the insulating coating 2 is cut at appropriate lengths to be discontinuous in the length direction. At locations where the insulation coating 2 is cut, the gaps between the strands 1 s of the stranded conductor 1, the gap between the outer peripheral surface of the stranded wire conductor 1 and the cut surface of the insulation coating 2 are filled with the water-stopping resin 3, Consists of water. Further, the water stop resin 3 is adhered to the cut surface of the insulating coating 2. As the water stop resin 3, a thermoplastic resin or a thermosetting resin having an adhesive property with the insulating coating 2 is used.
[0013]
As described above, the electric wire with the water stop portion is provided with a gap between the strands 1 s of the stranded wire conductor 1, the outer peripheral surface of the stranded wire conductor 1, and the cut surface of the insulating coating 2 at an appropriate interval in the length direction. Since the water stop portion is formed by the resin 3 for water stop filling the gap, even if water enters from the portion where the insulating coating 2 at the end of the electric wire or the intermediate portion is peeled off, Water running is prevented and obstacles do not spread over a wide area.
[0014]
Moreover, since the external appearance of this electric wire with a water stop part becomes the form where the insulation coating 2 cut | disconnected for every appropriate length was connected with the resin 3 for water stop, the distinction between a water stop part and the part which is not so When connecting terminals and the like, reliable electrical connection can be achieved by stripping off the insulating coating 2 while avoiding the water stop portion.
[0015]
In order to make the distinction between the water stop portion and the other portions clearer, the outer diameter of the water stop resin 3 is made larger than the outer diameter of the insulating coating 2 as shown in FIG. It is good to make it like a bamboo node, or to make the color of the water-stopping resin 3 different from the color of the insulating coating 2.
[0016]
Next, one Embodiment of the manufacturing method of the electric wire with a water stop part which concerns on this invention is described with reference to Fig.2 (a)-(d).
In this manufacturing method, first, as shown in FIG. 2A, an electric wire 4 is prepared in which a stranded conductor 1 is provided with an insulating coating 2 made of a thermoplastic resin. The electric wire 4 can be manufactured at a high speed by a normal extrusion coating process. When the electric wire 4 is intermittently traveled in the length direction and the travel stops, the notch blade 5 installed at a fixed position is used to cut the insulating coating 2 as shown in FIG. The insulating coating 2 is gripped by the first chuck 6A and the second chuck 6B. The cutting blade 5 is formed in a semicircular blade shape having an inner diameter slightly larger than the outer diameter of the stranded wire conductor 1 so as not to damage the stranded wire conductor 1. The chucks 6A and 6B are preferably provided with irregularities on the inner peripheral surface so that the gripped insulating coating 2 is not displaced.
[0017]
Next, the cutting blade 5 and the second chuck 6B are moved away from the first chuck 6A while the first chuck 6A is fixed in that position, and the cut surface of the insulating coating 2 is removed as shown in FIG. Leave an interval in between. As a result, the stranded wire conductor 1 is exposed. In this state, a liquid water-stopping resin 3e is supplied from the nozzle 7, and the water-stopping resin 3e covers the outer peripheral surface of the stranded wire conductor 1 and Fill gaps between lines 1s. In order to allow the water-stopping resin 3e to sufficiently enter the gap between the strands 1s in the stranded wire conductor 1, the first chuck 6A or the second chuck 6B is rotated in a direction in which the twist of the stranded wire conductor 1 is loosened. It is preferable to widen the gap between the strands 1s. When the first chuck 6A or the second chuck 6B is rotated in the direction in which the twist of the stranded conductor 1 is loosened, the first chuck 6A or the second chuck 6B is then rotated in the opposite direction to return to the original state.
[0018]
Next, after the nozzle 7 and the cutting blade 5 are retracted, the second chuck 6B is moved in the direction approaching the first chuck 6A as shown in FIG. The water-stopping resin 3e is sandwiched between the cut surfaces of the insulating coating 2. The operations so far are performed before the liquid water-stopping resin 3e is solidified. Thereafter, the first chuck 6A and the second chuck 6B are opened, and when the electric wire 4 runs in the length direction by one pitch, the state returns to (a). The water-stopping resin 3e sandwiched between the cut surfaces of the insulating coating 2 is solidified over time and adheres to the cut surface of the insulating coating 2. By repeating such a process, the electric wire with a water stop part like FIG. 1 can be manufactured.
[0019]
When the second chuck 6B is moved, the third chuck 6C that does not move away from the second chuck 6B as shown in FIG. 3 in order to facilitate pull-back after the insulating coating 2 is slackened. May be installed and opened and closed simultaneously with the second chuck 6B.
In the above-described embodiment, only the chuck on one side of the cutting blade is moved in the length direction of the electric wire, but the chucks on both sides can be moved.
[0020]
【The invention's effect】
As described above, according to the present invention, the insulation coating is cut for each appropriate length, and the gap between the strands of the stranded wire conductor, the gap between the outer peripheral surface of the stranded wire conductor and the cut surface of the insulation coating is provided there. Since the water stop portion is formed by filling the water stop resin so as to be buried, it is possible to manufacture an electric wire with a water stop portion with a reliable water stop effect. Further, since the water stop portion can be formed after applying an insulation coating to the stranded conductor to form an electric wire, manufacturing is easy, and the extrusion rate of the insulation coating is not reduced, and the productivity is also good.
[Brief description of the drawings]
FIG. 1 shows an example of an electric wire with a water stop produced by the production method of the present invention, wherein (a) is a partially cutaway side view, (b) is a cross-sectional view taken along the line bb of (a), (C) is the cc sectional view taken on the line of (a).
FIGS. 2A to 2D are partially cutaway side views showing an embodiment of a method for manufacturing an electric wire with a water stop according to the present invention.
FIG. 3 is a partially cutaway side view showing another embodiment of the method for manufacturing a wire with a water stop according to the present invention.
[Explanation of symbols]
1: Stranded wire conductor 1s: Wire 2: Insulation coating 3: Water stop resin 3e: Liquid water stop resin 4: Electric wire 5: Cutting blade 6A, 6B: Chuck 7: Nozzle

Claims

Prepare an electric wire with an insulation coating made of thermoplastic resin on the outer periphery of the stranded wire conductor, cut the insulation coating of this wire into appropriate lengths and leave a space between the cut surfaces of the insulation coating, thereby twisting Supply the liquid water-stopping resin where the wire conductor is exposed, cover the outer peripheral surface of the stranded wire conductor with the liquid water-stopping resin, and fill the gaps between the strands of the stranded wire conductor, and then insulation coating By narrowing the gap between the cut surfaces, the water-stopping resin adhering to the outer peripheral surface of the stranded wire conductor is sandwiched between the cut surfaces of the insulation coating, and in that state the water-stopping resin is solidified and the cut surface of the insulation coating The manufacturing method of the electric wire with a water stop part characterized by making it adhere to.

2. The method for producing an electric wire with a water stop portion according to claim 1, wherein when the water stop resin is supplied, the twist of the stranded wire conductor is loosened to widen a gap between the strands.