JP6648537B2 - Waterproof electric wire and method of manufacturing the same - Google Patents

Description

The present invention relates to a method of manufacturing waterproofing electric wires.

  For example, an electric wire connected to an electronic device such as an electronic control device of an automobile is provided with a water-stopping material for blocking moisture that tends to enter the electronic device via a gap existing inside the insulator. . For example, the electric wire waterproof structure of Patent Literature 1 has a core wire welded portion obtained by removing a part of an insulator of a covered electric wire and then welding an exposed core wire. The gap existing in the core wire weld is filled with a low-viscosity water-stopping material.

JP 2013-109847 A

  However, when the core wire waterproof structure of Patent Document 1 is formed, it is necessary to remove the insulator by peeling the insulated wire. Since such a stripping process requires a relatively complicated work process, there is a need for a technique for stopping water from an insulated wire without performing a stripping process.

  In addition, the above core wire waterproof structure has a problem that it is difficult to control the size of the gap formed in the core wire welding part when welding the exposed core wire. Therefore, if the size of the gap formed in the core wire weld is excessively large or excessively small, the water-stopping material may not be sufficiently filled, and it may be difficult to close the gap.

The present invention has been made in view of such background, can stop water without the skinning process, seeks to provide a process for producing waterproof electric wire having an excellent water stopping performance.

One embodiment of the present invention is a preparation step of preparing an insulated wire having a conductor including a plurality of conductor strands and an insulator covering the conductor,
A swelling step of swelling a part of the insulator outward to form a swelling portion,
A gap expanding step of expanding a gap between the conductor wires in the bulging portion,
A water stopping step of filling a water stopping material into the hole of the through hole, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor strands through the through hole formed in the bulging portion; And a method for manufacturing a watertight electric wire.

The water-blocking electric wire obtained by the above manufacturing method has a water-blocking material filled in the hole of the through-hole, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor strands. I have. Therefore, the water-stopping material blocks the movement of the water that has entered the inside of the insulator from one end of the water-stopping wire, and prevents the water from reaching the other end of the water-stopping wire. can do. Further, the water blocking material can also prevent moisture from entering the inside of the insulator through the through hole. Therefore, the waterproof electric wire obtained by the above-mentioned manufacturing method has excellent waterproof performance.

In the above SL manufacturing method, after the above swelling step, in the gap enlargement process gaps between the conductive wires is expanded. Then, the gap between the conductor strands is widened, and then the water stopping step is performed, whereby the gap between the conductor strands can be easily closed with the water stopping material. As a result, the water stopping performance of the water stopping electric wire obtained by the above manufacturing method can be improved.

  In the above-mentioned manufacturing method, in the above-mentioned water stopping process, the above-mentioned swelling part is filled with the above-mentioned water stopping material via the above-mentioned penetration hole. Therefore, the insulated wire can be water stopped without peeling the insulator, and a water stopped wire can be manufactured.

FIG. 2 is a cross-sectional view of a main part of the waterproof electric wire according to the first embodiment. FIG. 4 is a cross-sectional view illustrating an example of a swelling step in the first embodiment. FIG. 7 is a cross-sectional view illustrating an example of a gap enlarging step in the first embodiment. FIG. 4 is a cross-sectional view illustrating an example of a water stopping process in the first embodiment. FIG. 13 is a side view illustrating an example of a step of enlarging a gap between stranded wires in the second embodiment.

The water stopping electric wire obtained by the above manufacturing method will be described. In the watertight electric wire, the conductor is constituted by a plurality of conductor strands. For example, the conductor can be configured as a stranded wire in which a plurality of conductor strands are twisted in the same direction, or a collective wire in which a plurality of conductor strands are bundled without being twisted. The conductor is preferably made of a stranded wire. In this case, in the gap enlarging step, the gap between the conductor strands can be easily enlarged by untwisting the conductor strands arranged in the bulging portion. As a result, the gap between the conductor strands can be more easily closed by the water-stopping material, and the water-stopping performance of the water-stopping electric wire can be further improved.

  The material of the insulator is not particularly limited as long as the insulator can form a bulged portion in the bulging step. As the insulator, for example, a thermoplastic resin such as a vinyl chloride resin, a polyethylene resin, and a polypropylene resin can be used. Since the thermoplastic resin can be easily softened by heating, the swelling portion can be easily formed in the swelling step. Therefore, in this case, the productivity of the watertight electric wire can be further improved.

  The water blocking material is filled in the through holes, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor wires. Here, the gap between the outer surface of the conductor and the insulator refers to a gap formed between the insulator and the conductor element arranged at the outermost periphery among the plurality of conductor elements constituting the conductor.

  The water stopping material may be filled over the entire length of the water stopping electric wire in the axial direction, or may be filled only in a part in the axial direction. From the viewpoint of reducing the usage of the water-stopping material, it is preferable that the water-stopping material is filled only in a part of the water-stopping electric wires in the axial direction. In this case, it is possible to reduce the usage amount of the water stopping material as compared with the case where the water stopping material is filled over the entire length of the water stopping electric wire. In addition, if at least a part of the water-blocking electric wire in the axial direction is filled with the water-blocking material, it is possible to block the movement of the moisture that has entered the inside of the insulator.

  In addition, it is preferable that the water-stopping wire has a terminal connection portion to which a terminal is connected at both ends, and the water-stopping material is filled at least in a part between the terminal connection portions. That is, it is preferable that the terminal connection portion is not filled with the water blocking material. In this case, in the operation of attaching the terminal to the waterproof electric wire, the terminal connection portion can be easily peeled. Therefore, the workability of attaching the terminal to the water stopping electric wire can be further improved.

  When the water-stop wire has terminal connection portions at both ends, only a portion between the terminal connection portions is filled with the water-stopping material from the viewpoint of further reducing the usage of the water-stopping material. Is more preferable.

  Examples of the water-stopping material include thermoplastic resins such as thermoplastic acrylic resins, thermoplastic elastomers such as acrylic elastomers, thermosetting resins such as thermosetting silicone resins and epoxy resins, and thermosetting resins such as thermosetting silicone rubbers. It is possible to use a curable elastomer, a moisture-curable resin such as a moisture-curable silicone resin, a moisture-curable elastomer such as a moisture-curable silicone rubber, a UV-curable resin such as a UV-curable acrylic resin, and a UV-curable elastomer. it can.

  As the water stopping material, it is preferable to use a thermosetting resin or a thermosetting elastomer which exhibits a liquid state in an uncured state. Such a water-stopping material can be easily filled into the bulging portion through the through-hole of the insulator in the water-stopping step. In addition, the liquid thermosetting resin can easily close the gap between the outer surface of the conductor and the insulator and the gap between the conductor strands. After filling the uncured thermosetting resin in the through holes, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor strands, the thermosetting resin is cured. Thereby, the insulated wire can be more easily stopped.

  As the water blocking material, it is more preferable to use a thermosetting resin or a thermosetting elastomer having high adhesiveness to an insulator or a conductor strand. Specifically, it is more preferable to use heat-curable silicone rubber, heat-curable silicone resin, and epoxy resin as the water-stopping material. In this case, it is possible to more effectively suppress the entry of moisture into the interface between the water-stopping material and the insulator or the interface between the water-stopping material and the conductor strand. As a result, the water stopping performance of the water stopping electric wire can be further improved.

  As described above, the water stopping electric wire can be manufactured by sequentially performing the preparation step, the bulging step, the gap enlarging step, and the water stopping step.

  In the above-described preparation step, an insulated wire having a conductor composed of a plurality of conductor strands and an insulator covering the conductor is prepared. As described above, it is preferable to prepare an insulated wire having an insulator made of a thermoplastic resin from the viewpoint of easily forming the bulging portion in the bulging step.

  In the bulging step, a part of the insulator is bulged outward to form a bulged portion. As a method of swelling the insulator, for example, a method of swelling a part of the insulator by making the pressure inside the insulator relatively higher than the pressure outside the insulator can be used. That is, for example, by sending compressed air or the like from the end of the insulated wire to the inside of the insulator, a part of the insulator can be expanded. Alternatively, a part of the insulator may be expanded by reducing the pressure outside the insulator while maintaining the pressure inside the insulator. Further, a part of the insulator can be expanded by sucking the insulator from the outside.

  In the gap expanding step, the gap between the conductor strands in the bulging portion is expanded. For example, when the conductor is a stranded wire, one end of the swelling portion in the axial direction is fixed, and the other end is twisted in the circumferential direction to untwist the conductor wire in the swelling portion, thereby obtaining a conductor wire. The gap between them can be expanded. Further, when the conductor is a collective wire, the gap between the conductor wires can be expanded by compressing and compressing the bulging portion in the axial direction to flex the conductor wire. As described above, from the viewpoint of more easily expanding the gap between the conductor strands, it is preferable that the conductor be formed of a stranded wire.

  In the water stopping step, first, a through-hole is formed in the bulging portion so as to penetrate from the outer peripheral surface to the inner peripheral surface of the insulator. Next, the water blocking material is filled into the bulging portion through the through hole. At this time, by filling the waterproofing material until the inside of the bulging portion and the inside of the through hole are filled, the inside of the through hole, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor strands Can be filled with a waterproof material.

  In the water stopping step, after the filling of the water stopping material is completed, an operation of narrowing a gap between the conductor wires in the bulging portion and compressing the bulging portion may be performed. By performing these operations, the water-stopping material is brought into close contact with the inner surface of the swollen portion and the conductor strand, and moisture is formed at the interface between the water-stopping material and the insulator and at the interface between the water-stopping material and the conductor strand. Intrusion can be more effectively suppressed. As a result, the water stopping performance of the water stopping electric wire can be further improved.

  In the water stopping process, when the gap between the conductor strands is reduced and the bulging portion is compressed as described above, the filling of the water stopping material is stopped before the inside of the bulging portion and the inside of the through hole are filled. You may. By compressing the bulging portion, a water-stopping material can be filled in the hole of the through-hole, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor wires.

  The compression of the bulging portion can be performed in various modes. For example, by compressing the bulging portion from the entire circumference in the circumferential direction, the outer diameter of the bulging portion can be easily brought close to the outer diameter of the surrounding portion. In this case, the ease of handling of the waterproof electric wire can be made equal to that of a normal insulated electric wire.

(Example 1)
For the embodiment of the manufacturing method of the waterproofing conductive line will be described with reference to FIG. As shown in FIG. 1, the waterproof electric wire 1 includes a conductor 2 including a plurality of conductor strands 21, an insulator 3 covering the conductor 2, a through hole 31 penetrating the insulator 3, and a through hole 31. In the hole, there is a gap 30 between the outer surface of the conductor 2 and the insulator 3 and a waterproof material 4 filled in the gap 20 between the conductor strands 21.

  The water stopping electric wire 1 of the present example includes a preparation step of preparing an insulated wire 10 having a conductor 2 composed of a plurality of conductor strands 21 and an insulator 3 covering the conductor 2, and removing a part of the insulator 3 A bulging step of forming the bulging portion 32 by bulging inward (see FIG. 2); a gap expanding step of expanding the gap 20 between the conductor wires 21 in the bulging portion 32 (see FIG. 3); A stopper for filling the water-stopping material 4 into the gap 30 between the outer surface of the conductor 2 and the insulator 3 and the gap 20 between the conductor strands 21 through the through-hole 31 formed in the portion 32. It can be manufactured by the method for manufacturing the water-stop electric wire 1 having a water process (see FIG. 4).

  Hereinafter, a detailed configuration of the waterproof wire 1 will be described in detail together with a method of manufacturing the same.

  In the preparation step, an insulated wire 10 having a conductor 2 composed of a plurality of conductor strands 21 and an insulator 3 covering the conductor 2 is prepared. The conductor 2 in the waterstop wire 1 of the present example is a collective line in which seven conductor wires 21 are bundled. The insulator 3 is made of a thermoplastic resin.

  In the swelling step, as shown in FIG. 2, the swelling portion 32 is formed by swelling a part of the insulator 3 radially outward. The swelling step includes, for example, a wire holding hole 51 having the same inner diameter as the outer diameter of the insulated wire 10 and a cavity 52 formed at an intermediate portion of the wire holding hole 51 and having an inner diameter larger than the outer diameter of the insulated wire 10. Can be performed as follows using the mold 5 having the following.

  First, the insulated wire 10 is inserted into the wire holding hole 51 and the cavity 52 of the mold 5. Next, the mold 5 is heated to soften the insulator 3. Thereafter, the insulator 3 in the cavity 52 can be bulged radially outward by sucking the insulator 3 from the outside in the radial direction (arrow 100 in FIG. 2). After that, by taking out the insulated wire 10 from the mold 5, the bulging portion 32 corresponding to the shape of the cavity 52 can be formed.

  Instead of the above method, the inside of the insulator 3 is pressurized while keeping the inside of the cavity 52 at atmospheric pressure, or the inside of the cavity 52 is depressurized while keeping the inside of the insulator 3 at atmospheric pressure. Also, the bulging portion 32 corresponding to the shape of the cavity 52 can be formed.

  After the bulging portion 32 is formed, a gap expanding step of expanding the gap 20 between the conductor wires 21 in the bulging portion 32 is performed. In the case where the conductor 2 is a collective wire as in the present example, for example, as shown in FIG. 3, the bulging portion 32 is compressed in the axial direction of the insulated wire 10 (arrow 101), so that the conductor strand 21 is formed. It can be deflected (arrow 102). As a result, the gap 20 between the conductor strands 21 can be expanded.

  After expanding the gap 20 between the conductor strands 21, a water stopping step of filling the water stopping material 4 in the bulging portion 32 is performed. The water-stopping material 4 of the present embodiment is made of a thermosetting resin 41 which is in a liquid state in an uncured state. In the water stopping step, for example, a through-hole 31 is formed by inserting a nozzle (not shown) of the discharge device into the bulging portion 32. Then, the uncured thermosetting resin 411 is discharged from the nozzle to fill the gap 30 between the outer surface of the conductor 2 and the insulator 3 and the gap 20 between the conductor strands 21 with the thermosetting resin 411. Can be.

  In this example, after filling the inside of the bulging portion 32 with the thermosetting resin 411, as shown in FIG. 4, an operation of narrowing the gap 20 between the conductor wires 21 in the bulging portion 32 is performed, and then the bulging portion is expanded. An operation of compressing the protrusion 32 from the entire circumference in the circumferential direction is performed.

  Specifically, the gap 20 between the conductor strands 21 in a state where the thermosetting resin 411 is filled can be narrowed by pulling the bulging portion 32 from both sides in the axial direction of the insulated wire 10 (arrow 103). it can. Thereafter, the outer diameter of the bulging portion 32 can be reduced by compressing the bulging portion 32 from the entire circumference in the circumferential direction (arrow 104). At this time, the work of compressing the bulging portion 32 may be performed in a state where the insulator 3 is heated and softened.

  Then, after wiping out the thermosetting resin 411 flowing out of the through-hole 31 with the compression of the bulging portion 32, the thermosetting resin 411 existing in the bulging portion 32 is cured. As described above, the waterproof electric wire 1 can be obtained.

  The waterproof electric wire 1 of the present embodiment has the waterproof material 4 filled in the through hole 31, the gap 30 between the outer surface of the conductor 2 and the insulator 3, and the gap 20 between the conductor strands 21. ing. Therefore, the movement of moisture that has entered the inside of the insulator 3 can be blocked by the waterproof material 4. Further, since the water blocking material 4 is also filled in the holes of the through holes 31, it is possible to prevent moisture from entering the inside of the insulator 3 from the through holes 31. Therefore, the insulated wire 10 has excellent water stopping performance.

  Further, in the manufacturing method of this example, after performing the bulging step, the gap 20 between the conductor strands 21 is expanded in the gap expanding step. Then, the gap 20 between the conductor strands 21 can be easily closed by the water blocking material 4 by performing the water stopping process after expanding the gap 20 between the conductor strands 21. As a result, the water stopping performance of the insulated wire 10 can be improved.

  In the manufacturing method of this example, the uncured thermosetting resin 411 is filled in the bulging portion 32 through the through hole 31 in the water stopping process. Therefore, the insulated wire 10 can be stopped without performing the peeling process of the insulator 3, and the water stopped wire 1 can be manufactured.

  Further, in the manufacturing method of this example, in the water stopping step, after the filling of the thermosetting resin 411 is completed, the gap between the conductor wires 21 in the bulging portion 32 is reduced and the bulging portion 32 is compressed. I do. Therefore, the water-stopping material 4 is brought into close contact with the inner surface of the bulging portion 32 and the conductor strands 21, and the moisture between the water-stopping material 4 and the insulator 3 and the interface between the water-stopping member 4 and the conductor strands 21 are reduced. Can be more effectively suppressed from entering. As a result, the water stopping performance of the water stopping wire 1 can be further improved.

(Example 2)
This example is an example of a gap enlarging step when a stranded wire is used as the conductor 202. As shown in FIG. 5, the waterproof electric wire (not shown) of the present embodiment has a conductor 202 formed of a stranded wire in which a plurality of conductor strands 21 are twisted in the same direction.

  The waterproof electric wire of this example can be manufactured by the following method, for example. First, in a preparation step, an insulated wire 12 having a conductor 202 formed of a stranded wire and an insulator 3 covering the conductor 202 is prepared. Subsequently, the bulging portion 32 can be formed by performing the bulging step in the same manner as in the first embodiment.

  In the gap enlarging step, one end 321 of the bulging portion 32 in the axial direction of the insulated wire 12 is fixed, and the other end 322 is twisted in the circumferential direction to untwist the conductor strand 21 arranged in the bulging portion 32. (Arrow 105). Thereby, the gap 20 between the conductor strands 21 can be expanded. Thereafter, a water stopping step is performed in the same manner as in Example 1, whereby a water stopping electric wire can be manufactured.

  In the water stopping step, by twisting the bulging portion 32 in the direction opposite to the gap enlarging step, the conductor strands 21 can be twisted again, and the gap 20 between the conductor strands 21 can be narrowed. Others are the same as the first embodiment. Note that among the reference numerals used in FIG. 5, the same reference numerals as those used in FIG. 1 to FIG. 4 represent the same components and the like as those in the first embodiment unless otherwise specified.

  As in the present example, the insulated wire 12 having the conductor 202 formed of a stranded wire can make the gap 20 between the conductor wires 21 easier by untwisting the conductor wires 21 arranged in the bulging portion 32. Can be expanded. In this case, it is also easy to twist the conductor strands 21 inside the bulging portion 32 again. Therefore, by using the insulated wire 12 having the conductor 202 composed of a stranded wire, the workability of the gap enlarging step can be further improved, and the productivity of the watertight wire can be further improved. In addition, the same functions and effects as those of the first embodiment can be obtained.

The manufacturing method of the waterproofing conductive line is not intended to be limited to the aspects of Examples 1 and 2 described above, it can be changed as appropriate configuration within a range not to impair the purpose. For example, in the first embodiment, an example in which the gap 20 between the conductor strands 21 in the bulging portion 32 is reduced and the bulging portion 32 is compressed in the water stopping process has been described, but these operations are not performed. Alternatively, the thermosetting resin 41 may be cured.
A reference form of the waterproof wire according to the present invention is shown below.
[Item 1]
A conductor comprising a plurality of conductor strands;
An insulator covering the conductor;
A through hole penetrating the insulator;
A water stopping electric wire having a water stopping material filled in a hole of the through hole, a gap between the outer surface of the conductor and the insulator, and a gap between the conductor strands.
[Item 2]
A conductor consisting of a plurality of conductor strands;
An insulator covering the conductor;
A through hole penetrating the insulator;
It is made of a thermosetting resin or a thermosetting elastomer, and has a water blocking material filled in the through hole, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor strands. Is a still water wire.
[Item 3 ]
The waterstop wire according to the above items 1 and 2 , having a terminal connection portion to which a terminal is connected at both ends, and the waterstop material is filled in at least a part between the terminal connection portions. .

DESCRIPTION OF SYMBOLS 1 Water stopping electric wire 10, 12 Insulated electric wire 2, 202 Conductor 20 Gap 21 Conductor wire 3 Insulator 30 Gap 31 Through hole 32 Swelling part 4 Water stopping material

Claims (2)

A preparing step of preparing an insulated wire having a conductor composed of a plurality of conductor strands and an insulator covering the conductor,
A swelling step of swelling a part of the insulator outward to form a swelling portion,
A gap expanding step of expanding a gap between the conductor wires in the bulging portion,
A water stopping step of filling a water stopping material into the hole of the through hole, the gap between the outer surface of the conductor and the insulator, and the gap between the conductor strands through the through hole formed in the bulging portion; And a method for manufacturing a waterproof electric wire. The method for manufacturing a water-stop electric wire according to claim 1 , wherein in the water stopping step, a gap between the conductor wires in the bulging portion is narrowed and the bulging portion is compressed.

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