JPH02189811A - Conductor - Google Patents

Abstract

PURPOSE:To obtain such a conductor as being lightweight and having a small coefficient of thermal expansion, great tensile strength and god conductivity by coating the surface of its core made of carbon fiber with a metal coat of good conductivity. CONSTITUTION:A conductor 1 comprises a core 2 coated on its surface with a copper coat 4 by plating, the core 2 being formed by stranding of plural pieces of PAN type carbon fiber 3 formed from acrylic fiber obtained by spinning of polyacrylonitrile as raw material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a conductive wire used as a winding of an electric machine, a power transmission line, a power distribution line, an indoor electric wire, or a power supply line of various devices.

[Conventional technology]

Conventional conductor wires include bare copper wire, tin-plated copper wire, nickel-plated copper wire, tS+ core copper core high wire, and aluminum wire. Copper wires have excellent conductivity and are easy to align. Copper wire has strong tensile strength, tin-coated copper wire prevents oxidation of the copper wire and at the same time soldering improves performance, and aluminum wire is extremely lightweight.

[Problems to be Solved by the Invention] However, since all of these conductive wires are formed only of metal, they have a large coefficient of thermal expansion.

Therefore, for example, if a magnet wire whose outer periphery is insulated with resin is wound in a coil around a core with a low coefficient of thermal expansion, the magnet wire with a high coefficient of thermal expansion will separate from the core due to repeated heating and cooling. There was a problem that the coils would separate and the winding state of the coil would become loose.

Therefore, the main object of the present invention is to reduce the coefficient of thermal expansion of the conducting wire, and in addition, it is also an object of the present invention to reduce the weight of the conducting wire and increase its tensile strength.

[Means to solve the problem]

In order to solve this problem, the conductive wire according to the present invention is characterized in that the surface of a core material made of carbon fiber is coated with a metal film having good conductivity.

[Function] The conductive wire of the present invention is made of light, strong, and conductive carbon fiber as a core material, and its surface is coated with a highly conductive metal film, so it has strong tensile strength even though it is thin. ,
Furthermore, it is extremely lightweight and has excellent conductivity.

Note that if a plurality of these conductive wires are twisted together, the tensile strength will be further increased.

Furthermore, since the carbon fiber that forms the core material of the conducting wire has a very small coefficient of thermal expansion, even when the conducting wire is used as a magnet wire, problems such as loosening of the winding will not occur.

[Example] Hereinafter, an example of the present invention will be specifically described based on the drawings.

FIG. 1 is a sectional view showing an example of a conductive wire according to the present invention, and FIGS. 2 and 3 are a front view and a plan view of an electroplating apparatus for manufacturing the conductive wire.

The conducting wire 1 shown in FIG. 1 has a core material 2 made of three PAN-based carbon fibers with a wire diameter of 10 μm or less made from an acrylic wire spun using polyacrylonitrile as a raw material.
A copper coating is applied to the surface by the plating apparatus shown in FIGS. 2 and 3.

The apparatus shown in FIGS. 2 and 3 includes a pretreatment washing tank 5 for washing the surface of the core material 2 unwound from a feeding device such as a recoiler, and a plating bath 5 for cleaning the surface of the core material 2 that has been pretreated. A coating tank 6 that is immersed in a bath to form a copper film 4 on its surface, a post-processing washing tank 7 that washes the surface of the copper film 4 formed by the bath, and a drying and removal of the washing water. It is composed of a drying device 8.

The plating tank 6 has conductor rollers 9A and 9 for cathode electrodes made of copper that supply power by contacting the core material 2 made of conductive carbon fiber 3.3- on the entry and exit sides of the plating tank 6.
Guide rollers 10A and IOB are provided to immerse the core material 2, which is conveyed by passing a rack between the conductor rollers 9A and 9B, into the bath of the plating tank 6.

The guide rollers IOA and IOB, which are immersed in the plating bath, and their rotating shafts 11 are both molded from corrosion-resistant resin.

Moreover, in the mesogi tank 6, there is a guide roller 10A.

A pair of anode electrodes 12.12 formed of phosphorous copper plates are provided on both left and right sides of the core material 2 passing between the IOBs.

Ionic dissociation (CuSO4→Cu"+504"-) occurs in the copper sulfate solution that serves as the plating bath, and a direct current is applied to this solution using the core material 2 that becomes the cathode electrode and the anode electrode 12.12. When an electric field is applied, ion conduction occurs, and Cu'' approaches the electrode interface of the core material 2 made of carbon fibers 3, and is precipitated as a metal on the surface of the core material 2 by a partial cathode reaction, resulting in a good electrical conductivity. A copper coating 4 is formed.

The manufacturing method is shown in Table 1. and Table 2. When the process was carried out according to the bath composition and working conditions not shown in Table 3, a conductive wire 1 with excellent quality characteristics as shown in Table 3 was obtained.

<Table 1. 〉“Bath composition”〈Table 2. 〉“Working conditions”〈Table 3. > As is clear from these results, the conducting wire 1 according to the present invention has
If you compare it with an annealed copper wire with the same outer diameter,
Although it has the disadvantage of a decrease in electrical conductivity, it has various excellent advantages such as a tensile strength that is several times higher, a coefficient of linear expansion that is significantly lower, and a weight that is significantly reduced.

In addition, a core material 2 made by twisting a plurality of carbon fibers 3.
When using copper coating 4, some unevenness will occur on the surface of the conductive wire 1, and the smoothness of the surface will be slightly impaired. After mild cold working, the outer diameter is as shown in Table 3.
When the wire is drawn from 0.35 mm to 0.34 mm as shown in Figure 1, the tensile strength is increased.

It is possible to eliminate irregularities and smooth the surface without significantly changing properties such as electrical conductivity or coefficient of thermal expansion, and at the same time, the gloss of the copper coating 4 plated on the surface is also improved.

Further, the present invention is not limited to the case where a metal coating such as a copper coating 4 is coated on the surface of the core material 2 made of a plurality of carbon fibers 3.3- twisted together; The surface of the material may be coated with a metal film, or
The core material may be formed by twisting a plurality of carbon fibers coated with a metal film in this manner.

Further, the carbon fiber 3 is not limited to the PAN type, but may be a bi'f-type carbon fiber made by spinning P-y- to 41i.

Furthermore, the plating bath is not limited to a copper sulfate bath, but may also be a sulfated copper bath, a cyanide copper bath, or a bright birophosphate copper bath having excellent rehering action.

Furthermore, the present invention performs electroless plating in which the copper coating 11M4 can be obtained by immersing the core material 2 in a plating bath containing copper ions and a reducing agent, for example, instead of electroplating that requires an external power source. Good too.

Furthermore, the conductive wire 1 coated with the copper sheath 4 etc. by this electroless plating is further coated with copper, nickel or glue.
If electroplating is applied using Munato's plating solution, the appearance and physical properties will be significantly improved.

In addition, when electroless plating is performed, the surface of the core material 2 or the carbon fiber 3 serving as the core material is subjected to a chemical etching treatment in advance to increase the adhesion of the plating film and to impart hydrophilicity ζ1, and further, Catalytic nuclei required for the initial deposition of electroless plating (
A catalyst treatment is applied to form a catalyst (Pd, Ag, Au, etc.).

Further, in the conductor wire according to the present invention, an insulating coating made of vinyl chloride resin or the like is applied to the outer periphery of the conductor wire 1 whose surface is coated with a metal coating such as a copper coating 4 on the surface of the core material 2 by electroplating or electroless meso-coating. This includes those that have been applied.

〔Effect of the invention〕

As mentioned above, since the conductive wire according to the present invention uses carbon fiber as its core material, the coefficient of thermal expansion is very small.
In addition, it has excellent effects such as high tensile strength, light weight, and good conductivity, making it extremely useful as a conductive wire for voice coils.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a conductive wire according to the present invention, and FIGS. 2 and 3 are a front view and a plan view of an electroplating apparatus for manufacturing the conductive wire. Explanation of symbols 1-conducting wire, 2-core material, 3-carbon fiber, 4-copper coating (metal coating).

Claims (4)

[Claims] (1) A conductive wire characterized in that the surface of a core material (2) made of carbon fiber (3) is coated with a highly conductive metal film (4). (2) The conducting wire according to claim 1, wherein the core material is formed by twisting a plurality of carbon fibers. (3) A conductor wire characterized by being made by twisting together a plurality of carbon fiber core materials whose surfaces are coated with a highly conductive metal film. (4) The conductive wire according to any one of claims 1 to 3, wherein the outer periphery is coated with an insulating coating.