WO2019102980A1

WO2019102980A1 - Braided wire and wire harness

Info

Publication number: WO2019102980A1
Application number: PCT/JP2018/042758
Authority: WO
Inventors: 健介山田
Original assignee: 株式会社オートネットワーク技術研究所; 住友電装株式会社; 住友電気工業株式会社
Priority date: 2017-11-23
Filing date: 2018-11-20
Publication date: 2019-05-31
Also published as: JP2019096493A

Abstract

Provided are a braided wire (1) that can suppress strand breakage due to vibration, and a wire harness (3) that uses the same. The braided wire (1) has a plurality of strands (2) that are braided together. The shape of the braided wire (1) is cylindrical. The strands (2) are constructed from aluminum wire or aluminum alloy wire. When viewed in a cross-section that is perpendicular to a strand axis (20), the outer shape of each strand (2) has a pair of substantially parallel straight sections (21a), (21b).

Description

Braided wire and wire harness

The present invention relates to a braided wire and a wire harness.

BACKGROUND Conventionally, a braided wire formed by weaving a plurality of strands into a tubular shape is used in a wire harness used for a vehicle such as an automobile. For example, as described in Patent Document 1, a copper-based wire such as a bare soft copper wire, an oxygen-free soft copper wire, or a tin-plated soft copper wire has been used as a wire forming a braided wire of this type.

In recent years, in order to reduce the weight of the wire harness and the like, it has been studied to use an aluminum-based wire made of aluminum or an aluminum alloy instead of the copper-based wire.

JP, 2015-18756, A

However, in the case of a braided wire made of an aluminum-based wire, due to the vibration applied at the time of use such as when the vehicle is running, the wires are rubbed to locally destroy the oxide film, resulting in abrasion corrosion where the aluminum is abraded. When abrasion occurs, the wire wear progresses and may eventually break.

The present invention has been made in view of the above background, and an object of the present invention is to provide a braided wire capable of suppressing the breakage of a strand due to vibration and a wire harness using the same.

One aspect of the present invention is a tubular braided wire having a plurality of braided strands,
The wire is made of aluminum wire or aluminum alloy wire,
The outer shape of the wire is a braided wire having a pair of substantially parallel linear portions when viewed in a cross section perpendicular to the wire axis.

Another aspect of the present invention is a wire harness having the above-mentioned braided wire.

In the above-mentioned braided wire, the wire constituting the braided wire is composed of an aluminum wire or an aluminum alloy wire, and when viewed in a cross section perpendicular to the wire axis, the wire has a pair of straight portions having a substantially parallel outer shape of the wire. doing. In the case of a braided wire in which the outer shape of the strand is circular, the strands are in point contact with each other in the braided portion of the strand, whereas in the braided wire, the strands are in surface contact with each other in the braided portion of the strand. Therefore, according to the said braided wire, the stress by the vibration concerning the contact part of strands can be relieved, and a disconnection of a strand can be controlled.

The wire harness has the braided wire. Therefore, in the above-mentioned wire harness, even when vibration is loaded, disconnection of the strands of wire in the braided wire is suppressed. So, according to the said wire harness, the shield reliability by a braided wire can be improved.

FIG. 1 is an external view schematically showing a braided wire of Example 1; It is the figure which showed typically the II-II line cross section in FIG. It is the figure which showed typically the cross section perpendicular | vertical to the strand axis | shaft of the strand which comprises the braided wire of Example 1. FIG. It is the figure which showed typically the wire harness of Example 1, and the application example of the said wire harness.

In the braided wire, a plurality of strands are braided into a tubular shape. The wires are made of aluminum wires or aluminum alloy wires.

As an aluminum alloy, 1000 series Al alloy, 3000 series Al alloy, 5000 series Al alloy, 6000 series Al alloy, 7000 series Al alloy etc. can be illustrated, for example. In addition, as an aluminum alloy, for example, 0.1% to 1.5% of Mg, 0.03% to 2.0% of Si, 0.05% or more of Cu in mass% An example is an aluminum alloy having a chemical composition which contains 0.5% or less, the balance is Al and unavoidable impurities, and the mass ratio Mg / Si of Mg and Si is 0.8 or more and 3.5 or less. it can. The aluminum alloy having the above-mentioned chemical composition can have a tensile strength of 200 MPa or more and a conductivity of 50% IACS or more. Therefore, when the aluminum alloy having the above chemical composition is used, the strength and conductivity of the wire are enhanced, and a braided wire which can easily suppress breakage of the wire due to vibration can be obtained while securing good shielding performance. . The chemical composition may further contain at least one element of Fe: 0.1% to 1.0% and Cr: 0.01% to 0.5% by mass%. it can. Moreover, the said chemical composition can further contain at least 1 element of Ti: 500 ppm or less and B: 50 ppm or less by a mass ratio.

In the above-mentioned braided wire, the plurality of strands constituting the braided wire may be composed of aluminum wires or aluminum alloy wires of the same material, or aluminum wires or aluminum alloy wires of different materials. It is also good. According to the former configuration, in the entire braided wire, variations in bending characteristics of the strands are less likely to occur, and the bending characteristics are easily made uniform. Therefore, according to the configuration of the former, even in the case where bending and distortion are repeatedly received, it is difficult to generate a portion which is easily broken locally, and it becomes easy to suppress the breakage of the wire due to the vibration.

In the above-mentioned braided wire, an aluminum wire or an aluminum alloy wire may have a chemical conversion film, an alumite film (anodic oxide film), a rust preventive film, etc. on the surface. According to this configuration, the friction coefficient of the surface of the wire is reduced compared to the bare aluminum-based wire, and the slipperiness of the wires is easily improved, so that the above-described abrasion corrosion due to the vibration is easily suppressed.

Here, in the above-mentioned braided wire, the outer shape of the strand has a pair of substantially parallel linear portions when viewed in a cross section perpendicular to the strand axis. In the above, “substantially parallel” means not only when the pair of linear portions is completely parallel but also, for the one linear portion of the pair of linear portions, the other linear portion is −10 The case of being inclined at an inclination angle of 10 degrees or more is also included.

The strands in the braided wire can be formed, for example, by compressing and flattening a strand having a circular outer shape in a cross section perpendicular to the strand axis.

In the braided wire, the wire has a ratio of a distance between a pair of straight portions to a cross-sectional area of a cross section perpendicular to the wire axis (<distance between a pair of straight portions> / <a wire cross section perpendicular to the wire axis The cross-sectional area of ( ¹ ) can be 5 mm ^-1 or more and 20 mm ^-1 or less. According to this configuration, when forming a strand by compressing and flattening the strand whose outer shape is circular, a corner that may damage the adjacent strand at both ends of the pair of linear portions to be formed It is hard to form the corner where it stood. Moreover, according to the above configuration, the length of the pair of linear portions is not too short, and the pair of flat surfaces is reliably formed on the outer surface of the strand by the compression. Therefore, according to the above configuration, surface contact between the strands of wire can be ensured in the braided portion of the strand, and a braided wire that can easily obtain the effect of suppressing wire breakage can be obtained. As for the distance between a pair of linear portions, ten perpendiculars perpendicular to one linear portion are drawn at equal intervals on one linear portion, and these perpendiculars are respectively cut off by a pair of linear portions. It is taken as the average value of perpendicular length.

The ratio of the distance between a pair of linear portions to the cross-sectional area of the cross section perpendicular to the strand axis is preferably 5 in view of facilitating the formation of corner portions that may damage the adjacent strands described above. .5mm ^-1 or more, more preferably, ^{6 mm -1} or more, more preferably, 6.5 mm ^-1 or higher, even more preferably, it may be 6.7 mm ^-1 or higher. The ratio of the distance between the pair of linear portions to the cross-sectional area of the cross section perpendicular to the strand axis is preferably 19 mm ^-1 or less, from the viewpoint of promoting surface contact between the strands in the braided portion of the strand. More preferably, it can be 18 mm ⁻¹ or less, more preferably 17 mm ¹ or less, and even more preferably 16 mm ¹ or less.

The said braided wire WHEREIN: The external shape of a strand can be set as the structure which has a pair of circular arc-shaped part which connects between the edge parts of the same side in a pair of linear part. According to this configuration, it is easy to suppress damage between adjacent strands. Therefore, according to this configuration, it is possible to obtain a braided wire that is advantageous for suppressing disconnection due to vibration.

In the above-mentioned braided wire, it is good for the outline of a strand to be, for example, a rounded rectangular shape. According to this configuration, it is ensured that the outer shape of the strand has the pair of linear portions and the pair of arc-shaped portions. Therefore, the effect mentioned above can be made reliable. The rounded rectangular shape can also be referred to as a track shape used in athletics and the like.

In the above-mentioned braided wire, the breaking rate of the wire is preferably 30% or less, more preferably 25% or less, still more preferably 20% or less, from the viewpoint of improving the applicability to the vibration site in the vehicle. It is good. In addition, the measuring method of the disconnection rate of the strand in a braided wire is later mentioned by an experiment example.

The wire harness has the braided wire. Specifically, the wire harness may be configured such that at least a harness end is covered by the braided wire. At the end of the harness, the wires of the wire harness are often exposed. According to the above configuration, even if the wire is exposed at the end of the harness, the wire can be covered with the braided wire, and the wire of the braided wire is unlikely to be broken due to rubbing of the wires due to vibration. Therefore, according to the above configuration, it is possible to obtain a wire harness having a high reliability of shielding by a braided wire.

The wire harness may be configured to be connected to the vibration site outside of the vehicle. As a vehicle, a car, a train, a train, a motorcycle, etc. can be illustrated, for example. According to the above configuration, even when the braided wire vibrates repeatedly due to the vibration of the vibrating portion, the wire of the braided wire is hard to break, and therefore, a wire harness for a vehicle having high reliability of shielding by the braided wire can be obtained.

Specifically, the wire harness includes an electric wire, a protective material covering the outer periphery of the electric wire, a connector connected to the electric wire exposed from the protective material at the harness end, an end of the protective material and an end of the connector And the braided wire covering the outer periphery of the electric wire exposed from the protective material. In addition, as a protective material, a metal pipe etc. can be illustrated, for example. According to this configuration, when the connector of the wire harness is connected to the vibrating portion, even if the braided wire vibrates repeatedly due to the vibration of the vibrating portion, the strands of the braided wire are less likely to be broken. High quality wire harness can be obtained. In addition, as a vibration part, an engine of vehicles, such as a motor vehicle, a door opening and closing part (bending part), a motor, a battery, etc. can be illustrated.

In addition, each structure mentioned above can be combined arbitrarily as needed, in order to acquire each effect mentioned above etc., etc. FIG.

Hereinafter, the braided wire and wire harness of an Example are demonstrated using drawing.

Example 1
The braided wire of Example 1 will be described with reference to FIGS. 1 to 3. FIG. As shown in FIGS. 1 to 3, the braided wire 1 of the present example has a plurality of braided wires 2. The shape of the braided wire 1 is cylindrical. In addition, in FIG. 2, each strand 2 is abbreviate | omitted.

The strands 2 are made of an aluminum wire or an aluminum alloy wire. As shown in FIG. 3, the outer shape of the strand 2 includes a pair of substantially parallel

linear portions

21 a and 21 b when viewed in a cross section perpendicular to the strand axis 20. Moreover, in this example, the external shape of the strand 2 has a pair of arc-shaped

parts

22a and 22b which connect between the edge part of the same side in a pair of

linear parts

21a and 21b. The strands 2 are formed by compressing and flattening a strand (not shown) having a circular outer shape when viewed in a cross section perpendicular to the strand axis. Specifically, the outer shape of the strand 2 is a rounded rectangular shape. In the present example, the width w of the strands 2 shown in FIG. 3 can be, for example, 0.78 mm, and the height h of the strands 2 can be, for example, 0.26 mm.

Next, the wire harness of Example 1 will be described with reference to FIG. As shown in FIG. 4, the wire harness 3 of this example has the braided wire 1 of this example.

In this example, specifically, the wire harness 3 includes the electric wire 31, the protective material 32 covering the outer periphery of the electric wire 31, and the connector 33 connected to the electric wire 31 exposed from the protective material 32 at the harness end 30. A braided wire 1 is fixed to the end of the protective material 32 and the end of the connector 33 and covers the outer periphery of the electric wire 31 exposed from the protective material 32. In FIG. 4 an example is shown in which both harness ends 30 are covered by the braided wire 1. The protective material 32 is specifically a metal pipe.

In this example, the connector 33 on the one harness end 30 side is connected to the engine of the automobile which is the first vibration portion 4. Further, the connector 33 on the other harness end 30 side is connected to the battery of the automobile which is the second vibrating portion 5. In addition, the wire harness 3 of this example is a wire harness for underfloors arranged outside the car. The braided wire 1 is fixed to the end of the protective material 32 by caulking the ring member 34. The braided wire 1 is fixed to the end of the connector 33 by being tightened by a band member 35.

Hereinafter, samples of braided wire were prepared and evaluated. The experimental example will be described.

<Example of experiment>
An Al alloy wire (diameter: 0.26 mm) made of an aluminum alloy whose outer shape of the wire is a circular shape in cross section perpendicular to the wire axis was prepared. Aluminum alloy contains, by mass%, 0.1% to 1.5% of Mg, 0.03% to 2.0% of Si, 0.05% to 0.5% of Cu, the balance Is composed of Al and unavoidable impurities, and has a chemical composition in which the mass ratio Mg / Si of Mg and Si is 0.8 or more and 3.5 or less.

The prepared Al alloy wire is compressed by a roller made of cemented carbide W to obtain three types of flattened Al alloy wires (1), (2) and (3) having a compression ratio of 30%, 50% and 70%. The Each flattened Al alloy wire had a rounded rectangular shape when viewed in a cross section perpendicular to the wire axis. In the flattened Al alloy wire (1) having a compression rate of 30%, the ratio of the distance between the pair of linear portions to the cross-sectional area of the cross section perpendicular to the strand axis was 16.01 mm ⁻¹ . Further, in the flattened Al alloy wire (2) having a compression rate of 50%, the ratio of the distance between the pair of linear portions to the cross-sectional area of the cross section perpendicular to the strand axis was 11.49 mm ⁻¹ . In addition, the ratio of the distance between the pair of linear portions to the cross-sectional area of the cross section perpendicular to the strand axis was 6.78 mm ⁻¹ for the flattened Al alloy wire (3) having a compression ratio of 70%. The compression ratio (%) is a value calculated from 100 × (distance between a pair of linear portions after compression) / (wire diameter before compression).

A braided wire of Sample 1 was obtained by knitting a plurality of flattened Al alloy wires (1) into a tubular shape. A braided wire of Sample 2 was obtained by knitting a plurality of flattened Al alloy wires (2) into a tubular shape. A braided wire of Sample 3 was obtained by knitting a plurality of flattened Al alloy wires (3) into a tubular shape. Further, a braided wire of Sample 4 was obtained by braiding a plurality of Al alloy wires (wire diameter: 0.34 mm) having a circular outer shape before flattening and compression treatment with the above-mentioned rollers to obtain a tubular shape. In each of the produced braided wires, the number of strikes was 44 and the number of holdings was 4.

(Vibration test)
The breaking rate was determined when the braided wire was vibrated one million times with a constant strain (specifically, a strain with a curvature variation ΔK = 0.0056). In addition, the disconnection rate was calculated | required from the formula of 100x (the number of unbroken wire strands) / (the number of all wire strands). The case where the wire breakage rate is 10% or less is regarded as “A” as being excellent in the wire wire breakage suppressing effect due to the vibration. When the wire breakage rate is more than 10% and 30% or less, the wire breakage due to vibration can be suppressed as "B". When the wire breakage rate exceeds 30%, "C" is determined as wire breakage due to vibration can not be suppressed.

As a result of the vibration test, the breaking rate of the braided wire of sample 1 is 18%, the judgment is "B", the breaking rate of the braided wire of sample 2 is 9%, and the judgment is "A", sample 3 The breaking rate in the braided wire of the invention was 21%, the judgment was "B", the breaking rate in the braided wire of the sample 4 was 32.5%, and the judgment was "C".

From the above results, in the braided wire having a plurality of strands composed of Al wires or Al alloy wires, when viewed from the cross section perpendicular to the strand axis, the strand has a pair of substantially parallel linear portions It was confirmed that the wire breakage can be suppressed by adopting the configuration, even if vibration is repeatedly applied in a strained state. This is because the strands come into surface contact with each other at the braided portion of the strands, so that the stress due to the vibration applied to the contact portion between the strands is relaxed.

As mentioned above, although the Example of this invention was described in detail, this invention is not limited to the said Example and an experiment example, A various change is possible within the range which does not impair the meaning of this invention.

Claims

A tubular braided wire having a plurality of braided strands,
The wire is made of aluminum wire or aluminum alloy wire,
The outer shape of the strand has a pair of substantially parallel linear portions when viewed in a cross section perpendicular to the strand axis.
The braided wire according to claim 1 , wherein a ratio of a distance between the pair of linear portions to a cross-sectional area of a cross section perpendicular to the wire axis is 5 mm -1 or more and 20 mm -1 or less.
The braided wire according to claim 1 or 2, wherein the outer shape of the wire has a pair of arc-shaped portions connecting between the ends on the same side of the pair of linear portions.
The braided wire according to any one of claims 1 to 3, wherein an outer shape of the strand is a rounded rectangular shape.
A wire harness comprising the braided wire according to any one of claims 1 to 4.
The wire harness according to claim 5, wherein at least an end of the harness is covered by the braided wire.
An electric wire, a protective material covering the outer periphery of the electric wire, a connector connected to the electric wire exposed from the protective material at the end of the harness, and an end of the protective material fixed to the end of the connector The wire harness according to claim 5 or 6, further comprising: the braided wire covering the outer periphery of the electric wire exposed from the protective material.
The wire harness according to any one of claims 5 to 7, which is configured to be connected to the vibration site outside the vehicle in a vehicle.