JPH07249315A - Conductor for electric and electronic equipment with excellent bending resistance - Google Patents

Abstract

PURPOSE:To provide a conductor having relatively excellent electric properties and excellent in bending resistance by setting an elastic coefficient of a coaxially stranded core wire several times that of an outer layer wire. CONSTITUTION:A conductor 3 is coaxially stranded. An elastic coefficient of a core wire 1 is made 2.5 times or more that of an outer layer wire 2. In this conductor 3, an elemental wire of the outer layer wire is made of Cu or a Cu alloy excellent in conductivity while the core wire is made of metal selected from Mo and W, or an alloy composed of mainly Mo or W. As a result, it is possible to reduce a load of a conductive material as the outer layer wire with respect to extension generated when the conductor is bent so as to enhance bending resistance of the conductor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electronic equipment, measuring equipment,
The present invention relates to a conductor for electric and electronic equipment having excellent bending resistance, which can be used for medical equipment, information communication equipment, industrial robot equipment and the like.

[0002]

2. Description of the Related Art Conventionally, as a conductor for electric and electronic equipment, a stranded wire of pure copper which is concentrically twisted has been mainly used. However, although pure copper has good electrical properties such as conductivity, it has the drawback of poor mechanical properties such as tensile strength and flexibility.

In order to improve such defects in mechanical properties, copper alloys such as copper-tin alloys, copper-beryllium alloys and copper-silver alloys are sometimes used as conductors. However, such a copper alloy, when adding a large amount of elements to be added to improve mechanical properties,
It has a drawback that the electrical characteristics are significantly deteriorated.

[0004]

However, due to the remarkable progress, sophistication, and miniaturization of electric and electronic equipment in recent years, a wire rod having a smaller diameter than the wire rod for wiring, good electrical characteristics, and high reliability, That is, a conductor having higher flexibility has been desired.

An object of the present invention is to provide a conductor for electric / electronic equipment which has an outer diameter of the same level as that of a conventional wiring wire, has relatively good electric characteristics and is excellent in bending resistance. .

[0006]

MEANS FOR SOLVING THE PROBLEMS The conductor for electric / electronic equipment of the present invention is a metal wire in which the elastic modulus of the center line of the conductor for electric / electronic equipment twisted concentrically is 2.5 times or more the elastic modulus of the outer layer wire. It is characterized by

As the conductor used in the present invention, the outer layer wire is made of Cu or Cu alloy having excellent conductivity, and the center line is a metal selected from Mo or W, or the metal is the main component. It is desirable to use an alloy of

[0008]

As described above, the bending resistance of the conductor for electric and electronic equipment is improved by making the elastic coefficient of the concentric twisted center line 2.5 times or more the elastic coefficient of the outer layer wire. It is considered that the flexibility can be significantly improved by reducing the load burden of the conductive material that is the outer layer wire against the elongation that occurs when receiving the stress. In addition, the elastic coefficient of the center line is specified to be 2.5 times or more that of the outer layer,
If it is smaller than 2.5 times, the effect is small.

Furthermore, the reason why the outer layer wire is made of Cu or a Cu alloy is that it is
The center line is made of Mo or W, or an alloy of the metal, because the elastic modulus of Mo or W or the alloy of the metal is 2.
Since it is 5 times or more, not only the flexibility is improved,
The tensile strength of Mo or W or its alloy is 2
This is because the weight is extremely large, such as 00 kg weight / mm 2 or more, so that it has an advantage that the breaking load is significantly improved, particularly when the wire has a small diameter.

In addition, the elastic coefficient of the conductive material is 2. The elastic coefficient of not only the center line of the conductor twisted concentrically but also a part of the outer layer wire is 2.
The same effect can be obtained by using 5 times or more metal wires.

The conductor for electric and electronic equipment of the present invention is
Even if Sn, Ag, Ni, Au, or the like is plated, sufficient flexibility and electrical characteristics can be obtained.

[0012]

EXAMPLES Specific examples of the present invention will be described below. First, the wire rods shown in Table 1 were processed to a wire diameter of 40 μm,
Their electrical and mechanical properties were measured. The results are also shown in Table 1. These wire rods were configured as shown in Table 2 to form 7 concentric stranded wires, and the electrical resistance, breaking load and flexibility of these stranded wires were evaluated. For comparison, an annealed copper twisted wire (conventional example 15), a hard copper twisted wire (conventional example 16), a copper-tin alloy twisted wire (conventional example 17), and a copper-silver alloy twisted wire (conventional example 18) are similarly processed. The test was conducted.

[0013]

[Table 1]

[0014]

[Table 2]

Flexibility was evaluated by how many times bending stress was repeatedly applied to the twisted conductor to break the conductor twist. FIG. 2 is a schematic diagram for explaining the test method of this flexibility evaluation. Referring to FIG. 2, pass the conductor 3 between the two pulleys 4 and 5 and at the lower end of the conductor 3 50 g
Apply a load of 6. In this state, the upper end 3a of the conductor 3
Is gripped, and is first tilted to the pulley 4 side, then returned, and then tilted to the pulley 5 side. The radii of the pulleys 4 and 5 are 2 mm. In this way, the sample was bent a plurality of times, and the number of times of bending until the conductor 3 was broken was taken as the bending value.

As can be seen from Table 1, all of the sample Nos. 1 to 10 of the present invention according to the present invention have excellent characteristics in bending value. In addition, the strands of the conductor stranded wires of Inventive Example Nos. 1 to 10 were Sn
It was plated. When the same flexibility was evaluated for these as well, it was found that the flexibility was excellent similarly to the invention examples Nos. 1 to 10.

Further, a composite twisted wire having seven twists of the conductor twisted wires of Inventive Example Nos. 1 to 10 was manufactured, and the same flexibility was evaluated. As a result, it was found that the conductor twisted wire according to the present invention has excellent flexibility even in the state of being made into a composite twisted wire. Furthermore, when the conductor stranded wires of Inventive Examples Nos. 1 to 10 had 19 concentric strands and were evaluated for flexibility, it was found that the same effect was obtained.

[0018]

As described above, the conductor stranded wire according to the present invention is a conductor having excellent bending resistance and is excellent as a conductor for electric and electronic equipment.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating a concentric twisted conductor that is an embodiment of the present invention.

FIG. 2 is a schematic view showing a test state of flexibility with respect to a conductor in an example of the present invention.

[Explanation of symbols]

 1: Center line 2: Outer layer line 3: Conductor 3a: Upper end part 4, 5: Pulley 6: Load

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hajime Shiraishi 1-3-1 Shimaya, Konohana-ku, Osaka City, Osaka Prefecture Sumitomo Electric Industries, Ltd. Osaka Works

Claims (2)

[Claims] 1. A conductor for electric and electronic equipment, which is concentrically twisted, wherein the outer layer wire is made of copper or a copper alloy, and the elastic modulus of the center line is made 2.5 times or more the elastic coefficient of the outer layer wire. A characteristic conductor for electrical and electronic equipment with excellent bending resistance. 2. The electric conductor for electric and electronic equipment according to claim 1, wherein the center line of the twisted wire is made of Mo or W, or an alloy of the metals, and the electric resistance is excellent. Conductor for electronic equipment.