JP2008091283A - Electric wire, and wire harness using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric wire for a wire harness capable of increasing tensile strength without increasing the diameter of a twisted-wire conductor, hardly causing deterioration of conductivity, and facilitating disposal when it becomes a waste material. <P>SOLUTION: This electric wire has the twisted wire conductor 4 composed by twining a plurality of peripheral strands 3 around a center strand 2, and a resin coating 5 arranged around the twisted-wire conductor. In the electric wire, the diameter of the center strand 2 is 0.09-0.3 mm; the diameter D of the twisted-wire conductor 4 is 0.28-0.6 mm; the center strand 2 is formed of a hard Cu-Ag alloy wire; and the peripheral strand 3 is formed of a soft or hard Cu-Sn alloy wire. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric wire suitable for a wire harness and a wire harness using the electric wire.

  A wiring harness in which a large number of electric wires are bundled is used for in-vehicle wiring of an automobile. As an electric wire used for a wire harness, a wire formed by twisting a plurality of copper strands into a stranded conductor, and applying a resin coating to the stranded conductor is common. A typical example is shown in FIG. In this electric wire 1, six outer peripheral wires 3 are twisted around a central strand 2 to form a stranded conductor 4, and a resin coating 5 is applied around the stranded conductor 4. The center wire 2 and the outer peripheral wire 3 are both made of the same material, and copper or copper alloy is used. The center wire 2 and the outer peripheral wire 3 have the same diameter.

  A pressure contact terminal is often used for electrical connection of such electric wires. An example is shown in FIG. The press contact terminal 6 is formed with a slot 7 into which the electric wire 1 is pushed into a hard metal plate. Both sides of the slot 7 are blades 8, and the distance S between the blades 8 is set smaller than the diameter D of the stranded conductor 4 of the electric wire 1. For this reason, when the electric wire 1 is pushed into the slot 7, the resin coating 5 is cut by the blade 8, and the blade 8 bites into the stranded conductor 4, so that an electrical connection state can be easily obtained.

  By the way, in the electric wire for motor vehicles, there exists a need to use properly what differs in tensile strength according to a use. However, since the diameter of the stranded wire conductor is determined step by step according to the standard, the electric wire for automobiles has the same electrical performance, but the diameter is one step or two steps when higher tensile strength is required. It was common to deal with the use of the thick stranded conductor above. However, using a thick stranded wire conductor goes against the trend of reducing the diameter and weight of automobile wires.

  Therefore, in order to increase the tensile strength without changing the diameter of the stranded wire conductor, in Patent Document 1, a stainless steel wire is used as the central strand, and a stranded wire conductor formed by twisting copper or a copper alloy wire around it. An electric wire using a wire has also been proposed.

JP 2005-158450 A

  However, although a stranded wire conductor using a stainless steel wire as the center strand and twisted copper or copper alloy wire around it can certainly increase the tensile strength without increasing the diameter, the stainless steel wire Therefore, the electrical resistance as a stranded wire conductor is high, and it is difficult to obtain sufficient conductive performance. Moreover, since the stainless steel wire and the copper or copper alloy wire are mixed and twisted, there is a problem that it is difficult to separate and collect the stainless steel wire and the copper or copper alloy wire when the electric wire becomes waste.

  Accordingly, an object of the present invention is to use an electric wire that can increase the tensile strength without increasing the diameter of the stranded wire conductor, has little decrease in conductivity, and can be easily treated when it becomes waste. Is to provide a wire harness.

In order to achieve this object, an electric wire according to the present invention comprises a stranded conductor formed by twisting a plurality of outer peripheral strands around a central strand, and a resin coating provided around the stranded conductor. An electric wire having
The diameter of the central strand is 0.09 to 0.3 mm, the diameter of the stranded conductor is 0.28 to 0.6 mm,
The central strand is made of a hard Cu—Ag alloy wire, and the outer peripheral strand is made of a soft or hard Cu—Sn alloy wire.

  The wire harness according to the present invention is characterized in that a plurality of electric wires configured as described above are assembled.

  A hard (not annealed) Cu—Ag alloy wire has a conductivity of about 80% of that of an annealed copper wire, and has a tensile strength of 3 to 5 times that of an annealed copper wire. Further, a soft (annealed) or hard (not annealed) Cu—Sn alloy wire has an electrical conductivity of 50 to 70% of that of an annealed copper wire, and has a tensile strength of 2 to 2. There are about 5 times, and it is softer than Cu-Ag alloy wire, and the biting property of the blade of a press-contact terminal is also favorable. Therefore, the stranded wire conductor using a Cu-Ag alloy wire for the center wire and the Cu-Sn alloy wire for the outer peripheral wire greatly reduces the conductive performance compared to the stranded wire conductor in which all the strands are annealed copper wires. In addition, a high tensile strength can be obtained, and the biting property of the blade of the press contact terminal is good. Furthermore, since the entire stranded conductor is made of a copper-based alloy, it is easy to recover useful metals when the electric wire becomes waste.

  In addition, the electric wire according to the present invention can suppress an increase in diameter even when high tensile strength is required, and the diameter of the stranded wire conductor can be reduced if the tensile strength requirements are approximately the same. Therefore, by using this electric wire for the wire harness, the wire harness can be reduced in diameter and weight.

  1 to 4 each show an embodiment of an electric wire according to the present invention. In the figure, 1 is an electric wire, 4 is a stranded conductor formed by twisting a plurality of peripheral strands 3 around a central strand 2, and 5 is a resin coating provided around the stranded conductor 4.

The twisted conductor 4 of the electric wire 1 in FIG. 1 is obtained by twisting six outer strands 3 having the same diameter as the center strand 2 around the center strand 2.
The stranded conductor 4 of the electric wire 1 in FIG. 2 is formed by twisting the outer peripheral wires 3 having a diameter smaller than that of the central strand 2 around the central strand 2 so that the strands are adjacent to each other. .
The stranded conductor 4 of the electric wire 1 shown in FIG. 3 is formed by twisting around the central strand 2 so that the eight peripheral strands 3 having a smaller diameter than the central strand 2 are adjacent to each other. .
The stranded conductor 4 of the electric wire 1 in FIG. 4 is obtained by twisting around the central strand 2 so that five outer peripheral strands 3 larger in diameter than the central strand 2 are adjacent to each other. is there.

  In any of the electric wires 1, the diameter of the central strand 2 is 0.09 to 0.3 mm, the diameter D of the stranded conductor 4 is 0.28 to 0.6 mm, the central strand 2 is made of a hard Cu-Ag alloy wire, The strand 3 is comprised with the soft or hard Cu-Sn alloy wire.

  In the present invention, a hard Cu—Ag alloy wire is used as the central strand 2 because the Cu—Ag alloy wire has a conductivity of about 80% of that of an annealed copper wire and has a tensile strength of 3 to 3 of that of an annealed copper wire. Since there are five times as much, compared to the case of using a stainless steel wire, a sufficient amount of current can be passed through the center wire, and the tensile strength can be increased while maintaining good conductivity as the stranded wire conductor 4. Because. Specifically, the tensile strength of the annealed copper wire is generally 190 MPa, while the tensile strength of the Cu—Ag alloy wire is 580 to 1150 MPa with the same diameter.

  The reason why the Cu-Sn alloy wire is used as the outer peripheral wire 3 is that the soft or hard Cu-Sn alloy wire has a conductivity of 50 to 70% of that of the annealed copper wire, but the tensile strength is 2 ~ 2.5 times, the tensile strength can be increased without substantially impairing the conductivity of the stranded wire conductor 4, and it is softer than the Cu-Ag alloy wire and harder than the annealed copper wire. This is because the bite property of the blade is good and the stability of the bite state is also good.

Therefore, the stranded wire conductor 4 using a Cu—Ag alloy wire for the central strand 2 and a Cu—Sn alloy wire for the outer peripheral strand 3 should have a large diameter without substantially impairing conductivity. The tensile strength can be increased, and the diameter can be reduced if the tensile strength requirements are similar. Specifically, for example, a breaking strength of 70 N or more can be secured with a diameter of about 0.5 mm, and the diameter can be reduced to 0.13 mm ² size. Therefore, by using the electric wire according to the present invention, the wire harness can be reduced in diameter and weight, and in response to the demand for downsizing of the control circuit accompanying downsizing of electrical equipment etc., wiring in a narrower space is possible. Become.

Sectional drawing which shows one Embodiment of the electric wire which concerns on this invention. Sectional drawing which similarly shows other embodiment Sectional drawing which shows other embodiment similarly Sectional drawing which shows other embodiment similarly The front view which shows the state which connected the conventional electric wire to the press-contact terminal.

Explanation of symbols

1: Electric wire 2: Center wire 3: Outer peripheral wire 4: Twisted wire conductor 5: Resin coating 6: Pressure contact terminal 7: Slot 8: Blade

Claims (2)

An electric wire having a stranded conductor formed by twisting a plurality of peripheral strands around a central strand, and a resin coating provided around the stranded conductor,
The diameter of the central strand is 0.09 to 0.3 mm, the diameter of the stranded conductor is 0.28 to 0.6 mm,
The electric wire according to claim 1, wherein the central strand is made of a hard Cu-Ag alloy wire, and the outer peripheral wire is made of a soft or hard Cu-Sn alloy wire. A wire harness formed by collecting a plurality of the electric wires according to claim 1.

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