JP2014164823A - Wiring harness - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring harness that is able to prevent adhesion of moisture to a portion of contact with an electric wire without using a resin material and is able to simplify a manufacturing process.SOLUTION: A wiring harness 1 comprises an electric wire 10 and a crimped terminal 20. The electric wire 10 has: an insulation covered part 12 in which a core wire is covered with an insulator; and a core wire exposed part 11 in which part of the core wire is exposed from the leading end of the insulation covered part 12. The crimped terminal 20 has: a box part 21, which is located at a leading end part 20A thereof; and a crimped part 22, which is located at a trailing end part 20B and into which the electric wire 10 can be inserted. The crimped part 22 includes: a covered crimped part 24 which is open in the trailing end part 20B and is crimped to the insulation covered part 12; and a core wire crimped part 23 which is crimped to the core wire exposed part 11. The covered crimped part 24 is provided with first and second projection parts 25A, 25B projecting inside in a radial direction.

Description

  The present invention relates to a wire harness used in an automobile or the like.

  Conventionally, in the fields of automobiles, OA equipment, home appliances, and the like, wire harnesses in which conductive wires having excellent electric conductivity are used as power lines and signal lines are known. The wire harness includes a crimp terminal that is attached to an electric wire and used for connection to other devices. The electric wire has a covering portion coated with an insulator and an exposed portion of the conductor portion where the core wire is exposed from the tip of the covering portion, and the crimping terminal is crimped to each of the covering portion and the exposed portion, thereby providing conductivity. The wire harness is configured. From the viewpoint of weight reduction, an electric wire using aluminum as a core wire material is attracting attention. As the crimp terminal, copper having excellent electrical characteristics is often used.

  For example, when moisture adheres to a contact portion of different metals such as aluminum and copper, so-called galvanic corrosion may occur due to a difference in standard electrode potential. In particular, since the standard electrode potential difference between aluminum and copper is large, corrosion on the aluminum side, which is electrically base, proceeds. For this reason, the connection state between the core wire and the crimp terminal becomes unstable, and there is a risk that an increase in contact resistance or an increase in electrical resistance due to a decrease in the wire diameter, or a disconnection, leading to malfunction of an electrical component or a malfunction.

  Among such wire harnesses in contact with different types of metals, there is one in which a resin material is filled so as to cover a connection portion between an electric wire and a crimp terminal (Patent Document 1). By filling the resin material, moisture is prevented from adhering to the contact portion between the electric wire and the crimp terminal.

JP 2004-111058 A

  However, in the method of Patent Document 1, since the resin material must be separately filled, the manufacturing process becomes complicated, and accordingly, the management in the manufacturing process becomes complicated. In addition, the cost of the entire wire harness increases due to the complexity of the process. Therefore, a water stop method that does not use a resin material is desired.

  The present invention has been made in view of such a problem, and can prevent moisture from adhering to a contact portion with an electric wire without using a resin material, and can simplify the manufacturing process. An object is to provide a simple wire harness.

  In order to achieve the above-described object, the present invention provides an electric wire having an insulating coating portion in which a conductive core wire is covered with an insulator, a core wire exposed portion in which the core wire is exposed from a longitudinal end of the insulating coating portion, and the insulating coating. A wire harness including a coated crimping portion to be crimped to a portion and a crimp terminal having a core wire crimping portion to be crimped to the core wire exposed portion, wherein the core wire crimping portion and the coated crimping portion have the electric wire in the longitudinal direction. The crimp terminal has a hollow shape that is watertight in the circumferential direction, the crimp terminal is located on the opposite side of the core crimp part, and the hollow inner surfaces are water-tight with each other. A sealing portion; and two protruding strips provided in the covering crimping portion and projecting inward in the radial direction and spaced apart in the longitudinal direction. The spacing dimension of the protruding strip in the longitudinal direction is the insulator. Thickness of A wire harness, characterized in that less than 5 times the size.

  The protruding line portion may be provided in an annular shape in the circumferential direction of the covering crimping portion.

  The core wire may be made of an aluminum material, and the core wire crimping portion may be made of a copper material.

  According to the present invention, the core wire crimping portion of the crimp terminal is crimped to the core exposed portion of the electric wire, the coating crimping portion is crimped to the insulating coating portion, and further, two protruding strips are provided on the coating crimping portion, and the separation dimension thereof However, since the thickness is 5 times or less of the thickness of the insulator, it is possible to reliably prevent moisture from entering and prevent moisture from adhering to the contact portion between the electric wire and the crimp terminal. Furthermore, since the intrusion of moisture can be prevented only by providing the ridges, there is no need to use a separate resin material or the like, and the cost increase correspondingly can be suppressed.

  Moreover, since the protruding portion is provided in a ring shape in the circumferential direction of the insulating coating portion, it can be kept watertight in the entire circumferential direction.

  ADVANTAGE OF THE INVENTION According to this invention, the adhesion of the water | moisture content to a contact part with an electric wire can be prevented without using a resin material, and the wire harness which can aim at the simplification of a manufacturing process can be provided.

The exploded perspective view of a wire harness. The perspective view of the wire harness after crimping | compression-bonding. III-III sectional view taken on the line of FIG. FIG. 4 is a partially enlarged view in the vicinity of the coated crimping portion of FIG. 3, and is a cross-sectional view when an electric wire insulator is also cut. Outline explanatory drawing of an experimental method.

  FIG. 1 is an exploded perspective view of the wire harness 1 and shows a state before the crimping portion 22 is crimped. The wire harness 1 has a longitudinal direction X and a width direction Y orthogonal to the longitudinal direction X, and includes an electric wire 10 and a crimp terminal 20. The electric wire 10 includes an insulation coating portion 12 in which a conductive core wire 16 is covered with an insulator 15 and a core wire exposure portion 11 in which a part of the core wire 16 is exposed from the distal end in the longitudinal direction X of the insulation coating portion 12. The core wire 16 is made of an aluminum-based material such as aluminum or an aluminum alloy, and more specifically, is formed by twisting a plurality of aluminum alloy wires or the like.

  The crimp terminal 20 extends in the longitudinal direction X, and is a crimp that allows insertion of a male connector (not shown) located at the front end 20A in the longitudinal direction X and a wire 10 located at the rear end 20B. Part 22. The box portion 21 includes an elastic contact piece 21A that comes into contact with the insertion tab of the male connector.

  The crimping part 22 includes a core crimping part 23 and a covering crimping part 24. The core wire crimping part 23 is located between the covering crimping part 24 and the box part 21. The cover crimping part 24 has a hollow cross section extending in the longitudinal direction X so that the electric wire 10 can be inserted from the rear end part 20B while opening to the rear end part 20B. The crimping terminal 20 is formed by punching a copper alloy strip such as brass whose surface is tin-plated into a flattened terminal shape (not shown), and then forming a box portion 21 of a hollow quadrangular prism body and a crimping portion 22 of a hollow cylindrical body. It is formed by bending into a three-dimensional terminal shape composed of Furthermore, between the box part 21 and the crimping | compression-bonding part 22, the sealing part 26 which made the hollow inner surface contact mutually watertight is provided. The sealing portion 26 is formed by bringing the inner surfaces of the crimping portion 22 into contact with each other and being joined in a watertight manner. As such a joining method, for example, pressure bonding or laser welding can be used.

  The crimping part 22 is joined in a watertight manner by a joining part 29 extending in the longitudinal direction X. Specifically, the end portions of the copper alloy strip punched into the terminal shape can be butted together so as to form a hollow shape, and the joined portion 29 can be formed by welding such as laser welding.

  The covering crimping portion 24 is provided with a first protruding strip portion 25A and a second protruding strip portion 25B. The first and second ridge portions 25 </ b> A and 25 </ b> B are each formed in an annular shape that is continuous in the circumferential direction of the crimping portion 22. The first ridges 25A and the second ridges 25B are provided apart in the longitudinal direction X.

  FIG. 2 shows the crimping terminal 20 with the core wire crimping portion 23 and the covering crimping portion 24 crimped radially inward after inserting the electric wire 10, and FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. . The electric wire 10 is inserted so that the core wire exposed portion 11 of the electric wire 10 is located in the core wire crimping portion 23 and the insulating coating portion 12 is located in the covering crimping portion 24. The dimension in the longitudinal direction X of the crimping part 22 is larger than the dimension in the longitudinal direction X of the core wire exposed part 11. Therefore, when the electric wire 10 is inserted into the crimping portion 22, the core wire exposed portion 11 and the insulating coating portion 12 are positioned to face the inner periphery of the crimping portion 22.

  By crimping the crimping part 22 with the core wire exposed part 11 and the insulation coating part 12 inserted into the crimping part 22, the core wire crimping part 23 and the core wire 16 of the core wire exposing part 11 are crimped and insulated from the coating crimping part 24. The insulator 15 of the covering portion 12 is pressure bonded.

  Since the covering crimping portion 24 is provided with the first and second projecting strip portions 25A and 25B, when the crimping portion 22 is caulked, the first and second projecting strip portions 25A and 25B are used to The part is crimped with a stronger force than the other parts.

  FIG. 4 is an enlarged perspective view of the first and second ridge portions 25A and 25B. The distance D1 between the first ridge portion 25A and the second ridge portion 25B is not more than five times the dimension D2 in the thickness direction of the insulator 15 of the electric wire 10. The separation dimension D1 is measured between the inner ends of the first and second protruding strip portions 25A and 25B facing each other. In addition, the thickness dimension D2 of the insulator 15 refers to a dimension at a portion not subjected to the pressing action at the crimping portion 22. Specifically, it is the thickness dimension of the insulator 15 in the exposed portion that is not inserted into the crimping portion 22. In other words, it is the thickness dimension of the insulator 15 before crimping.

<Experimental example>
In the wire harness 1 as described above, air was sent from the insulation coating portion 12 of the electric wire 10 toward the crimp terminal 20, and an experiment was conducted as to whether air leaks from the rear end portion 20B. FIG. 5 shows an outline of the experimental method. In the experiment, the crimp terminal 20 that crimped the electric wire 10 was put in a water tank 41 containing water, and pressurized air was sent from the end of the electric wire 10 toward the crimp terminal 20 by the regulator 42. Pressurized air was discharged at 50 kpa for 30 seconds.

  As the wire harness 1, controls, samples 1 to 4 were prepared, and the number of each sample was n = 10. The control is a wire harness using the crimp terminal 20 in which the protruding crimp part is not provided in the coated crimp part 24. Sample 1 is a wire harness using a crimp terminal 20 in which the distance D1 between the two ridges 25A and 25B is eight times the thickness D2 of the insulator 15. Sample 2 is a wire harness using a crimp terminal 20 having a separation dimension D1 that is six times the thickness dimension D2 of the insulator 15. Sample 3 is a wire harness using a crimp terminal 20 having a separation dimension D1 that is five times the thickness dimension D2 of the insulator 15. Sample 4 is a wire harness using a crimp terminal 20 in which the separation dimension D1 is four times the thickness dimension D2 of the insulator 15. Sample 3 and sample 4 are wire harnesses according to this embodiment. Moreover, about the control | contrast, the wire harness heated for 24 hours at 120 degreeC and the wire harness which does not perform such a heating were prepared. In Samples 1 to 4, a wire harness heated at 120 ° C. for 24 hours and 120 hours and a wire harness without such heating were prepared. The wire harness 1 may be used in a high-temperature environment, and particularly when used in such a high-temperature environment, the elasticity of the insulator 15 is reduced, and the crimping portion 22 and the insulating coating portion 12 are separated. There exists a tendency for the crimping force between to fall. In this experiment, it is possible to confirm the durability of the use of the wire harness 1 in a high temperature environment.

  As shown in Table 1, enter “N” for those where there was no air leakage from the rear end 20B of the crimp terminal 20, and if there was a leak, enter the pressure at the time of leakage. doing. Air leakage was performed by visually checking the bubbles.

  In the control in which no ridges were provided, no air leakage was observed when no heat treatment was performed, but in the 24-hour heat treatment, air leakage was confirmed at 1 KPa or less. In Samples 1 to 4, no air leakage was confirmed when no heat treatment was performed.

  In sample 1, in the heat treatment for 24 hours, no air leakage was confirmed in 7 samples, but air leakage was confirmed at a pressure of 30 KPa for one and two for 20 KPa. In the heat treatment for 120 hours, air leakage was confirmed at a pressure of 1 to 3 KPa in all cases.

  In sample 2, in the heat treatment for 24 hours, no air leakage was confirmed in eight samples, but one was confirmed to be air leakage at a pressure of 40 KPa and one was 50 KPa. In the heat treatment for 120 hours, no air leakage was confirmed in the five samples, but air leakage was confirmed in the remaining five samples at a pressure of 5 to 30 KPa.

  In Sample 3 and Sample 4, no air leakage was observed in either the 24-hour heat treatment or the 120-hour heat treatment. Therefore, the separation dimension D1 of the first and second protrusions 25A, 25B is not more than 5 times the thickness dimension D2 of the insulator 15, so that the wire harness 1 is used in a high temperature environment. It has also been proved that the inside of the crimp terminal 20, particularly the inside of the core wire crimp part 23, can be kept watertight. By setting the spacing dimension D1 to be not more than 5 times the thickness dimension D2 of the insulator 15, the insulator 15 may enter the spacing portion in the longitudinal direction X of the first and second protrusions 25A and 25B. It is assumed that the water tightness is improved.

  As described above, moisture is infiltrated from the rear end portion 20B to the box portion 21 side by setting the separation dimension D1 of the first and second protruding strip portions 25A, 25B to be not more than five times the thickness dimension D2 of the insulator 15. Can be surely prevented. That is, the core wire crimping part 23 can be kept watertight. Therefore, electrolytic corrosion due to contact between the core wire 16 and the crimp terminal 20 can be reliably prevented.

  In the insulation coating part 12, what is normally used in the field | area of this technique, such as the polyvinyl chloride (PVC) which has elasticity, and polyethylene, can be selected as the insulator 15 which covers the core wire 16. FIG.

  In the wire harness 1 as described above, the core wire 16 of the electric wire 10 is made of an aluminum-based material, and the core wire crimping portion 23 of the crimp terminal 20 is made of a copper-based material. Contact. There is a possibility of electrolytic corrosion due to moisture adhering at the part where the different metal contacts, but in this embodiment, it is possible to prevent the penetration of moisture into the crimping part 22 and thus prevent electrolytic corrosion. Can do. Further, according to this embodiment, even if a material normally used as the material of the insulator 15 is used, it is possible to reliably prevent moisture from entering the crimping portion 22.

  In this embodiment, the first and second convex strip portions 25A and 25B have the same radial dimension. However, they may have different dimensions. The electric wire 10 can be easily inserted by making the first ridge portion 25A located on the box portion 21 side larger than the second ridge portion 25B located on the rear end portion 20B side. In addition, by making the second ridge portion 25B larger than the first ridge portion 25A, it is possible to maintain the flexibility of the core wire exposed portion 11 and keep the crimped state against the core wire crimp portion 23.

  Although the cross-sectional shape of the 1st and 2nd protruding item | line parts 25A and 25B is made into the substantially rectangular shape, it is not restricted to this shape. For example, the cross-sectional shape may be a polygon such as a circle or a triangle. In addition, the cross-sectional shape of the radially inner portions of the first and second ridges 25A and 25B may be inclined to an axis extending in parallel with the longitudinal direction X. That is, you may incline so that the diameter may become large toward the rear end part 20B side from the front end part 20A side. By inclining in this way, when the electric wire 10 is inserted from the rear end 20B side, it is relatively easy to insert, but it is difficult to move in the opposite direction, and the inserted electric wire 10 can be made difficult to come off. Furthermore, the cross-sectional shape may differ between 1st protruding item | line part 25A and 2nd protruding item | line part 25B.

  As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs.

DESCRIPTION OF SYMBOLS 1 ... Wire harness 10 ... Electric wire 11 ... Core wire exposed part 12 ... Insulation coating | cover part 15 ... Insulator 16 ... Core wire 20 ... Crimp terminal 21 ... Box part 22 ... Crimp part 23 ... Core wire crimp part 24 ... Cover crimp part 25A ... 1st Convex section 25B ... Second convex section 26 ... Sealing section X ... Longitudinal direction

Claims (3)

An electric wire having an insulation coating portion in which a conductive core wire is coated with an insulator, and a core wire exposure portion in which the core wire is exposed from the longitudinal tip of the insulation coating portion, and a coating crimp portion and the core wire to be crimped to the insulation coating portion A wire harness including a crimp terminal having a core crimp part to be crimped to the exposed part,
The core wire crimping part and the covering crimping part have a hollow cross-sectional shape that allows the electric wire to be inserted in the longitudinal direction and is watertight in the circumferential direction,
The crimp terminal is located on the opposite side of the core crimp part from the coated crimp part, and a sealing part in which the hollow inner surfaces are water-tight with each other;
Provided with two protruding strips provided in the covering crimping portion and projecting inward in the radial direction and spaced apart in the longitudinal direction;
The wire harness according to claim 1, wherein a separation dimension of the protrusions in the longitudinal direction is not more than five times a thickness dimension of the insulator.   The wire harness according to claim 1, wherein the ridge portion is provided in an annular shape in a circumferential direction of the covering crimping portion.   The wire harness according to claim 1 or 2, wherein the core wire is made of an aluminum-based material, and the core wire crimping portion is made of a copper-based material.

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