JP2003331672A - Manufacturing method for rectangular insulated wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a rectangular insulated wire of which the conductor surface is not exposed by forming a uniform coating throughout its entire surface including the corners after baking without drastic changing in such a method so as to coat an insulating coating material on the outer surface of a rectangular wire and bake it, thus repeating them more than once. <P>SOLUTION: This manufacturing method for a rectangular insulated wire includes following processes: a rolling process f1 for forming a rectangular conductor by pressing a circular wire; a plasma treatment process f2 for improving wettability on the entire surface or at the selectively only corners of the rectangular conductor; and the coating/baking process of a coating material/an ultraviolet radiation process f3 in which the coating/baking of an insulating coating material on the outside of the rectangular conductor completed the plasma treatment are repeated more than once. In the process f3, wettability on the entire or at the selectively only corners of a thin insulating coating formed intermediate is improved by irradiating ultraviolet radiation there, thereby the rectangular insulated wire having excellent insulating characteristics is manufactured. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a rectangular insulated wire. More specifically, the voice coil of the speaker,
Small motor coil for video tape recorder (VTR), choke coil, linear voice coil for optical pickup,
The present invention relates to a method of manufacturing a rectangular insulated wire used for a motor coil for a floppy disk, a noise filter and the like.

[0002]

2. Description of the Related Art A method of manufacturing a flat insulated wire is a method of rolling a round conductor having a circular cross section into a flat conductor, and applying an insulating paint to the outer periphery of the flat conductor by baking according to a conventional method. Is applied and baked, and then rolled to transform into a rectangular insulated wire.

[0003]

In any of the above-described methods for manufacturing a rectangular insulated wire, there are the following problems. That is, in the former method, when the insulating paint is applied and baked on the outer periphery of the rectangular conductor, its fluidity increases as the temperature of the paint increases, and the film at the corners after baking becomes thin to obtain a film with a uniform thickness. Is difficult. Therefore, when a flat insulated wire having a thin film on the corners and a conductor surface exposed is used for the coil winding of an electric device, it causes insulation failure and significantly reduces the reliability of the device. On the other hand, in the latter method,
Although it is possible to obtain a film having a uniform thickness, there is a problem of deterioration in characteristics due to work hardening of the conductor by rolling and work deterioration of the insulating film. The work-hardened conductor can be softened by heat treatment, but the work-deteriorated film has poor thermal shock resistance and cracks or peeling may occur. This phenomenon becomes more remarkable as the thickness-width ratio of the rectangular insulated wire increases.
When the rolling ratio is higher than the above, innumerable cracks and peeling occur, the conductor surface is exposed, and the insulation characteristics are significantly deteriorated.
Therefore, it cannot be applied to the coil.

The present invention has been made in order to solve the various problems of the above-mentioned prior art, and is the first conventional method, which is a rectangular insulated wire in which an insulating paint is applied and baked on the outer periphery of a rectangular conductor a plurality of times. An object of the present invention is to provide a method for producing a rectangular insulated wire in which a uniform film is formed over the entire surface including a corner after baking without exposing the conductor surface without making a drastic change in the production method. To do.

[0005]

As a first aspect of the present invention, the present invention provides a rectangular insulated wire in which an insulating paint having a predetermined coating thickness is formed by coating and baking an insulating paint a plurality of times on the outer periphery of a rectangular conductor. A rolling step of rolling a circular conductor having a circular cross-section into a rectangular conductor; and plasma for plasma-treating the rectangular conductor to improve the wettability of the entire conductor or selectively the corner portion of the conductor. A treatment step; and applying an insulating coating to the outer periphery of the plasma-treated rectangular conductor a plurality of times to form an insulating coating of a predetermined coating thickness During coating and baking, a thin insulating coating is formed on the outside of the rectangular conductor A coating application baking / ultraviolet irradiation treatment step for improving the wettability of the entire intermediate body or selectively the corner portions of the intermediate body by irradiating the body (hereinafter abbreviated as intermediate body) with ultraviolet rays;
The method for producing a rectangular insulated electric wire is characterized by producing a rectangular insulated electric wire having excellent insulation properties by In the method of manufacturing a flat insulated wire according to the first aspect, by performing the plasma treatment step, the wettability of the entire flat conductor or selectively the flat conductor corner is improved, so that the affinity between the conductor corner and the paint is improved. It becomes large, and film forming properties are imparted to the corner portions of the conductor. Next, in the paint coating baking / ultraviolet irradiation treatment step, the intermediate body is subjected to ultraviolet ray irradiation treatment to improve the wettability of the entire surface of the intermediate body or selectively the corner portions of the intermediate body without damaging the insulating film. As a result, an insulating film with excellent adhesion is uniformly formed over the entire surface including the corners,
The conductor surface is not exposed, and it is possible to manufacture a flat insulated wire having excellent insulation properties.

As a second aspect, the present invention is a method of manufacturing a flat insulated wire, wherein the flat conductor is copper, aluminum or copper clad aluminum. In the manufacturing method of the second aspect, as the rectangular conductor, copper, aluminum,
Alternatively, copper clad aluminum can be preferably used.

As a third aspect, the present invention resides in a method for producing a rectangular insulated wire, wherein the wettability of the entire surface or corners of the plasma-treated rectangular conductor is 60 mN / m or more in surface tension.
In the manufacturing method of the third aspect, the wettability of the entire surface or the corner portion of the plasma-treated flat rectangular conductor is 60 mN / m in terms of surface tension.
As described above, the wettability of the entire surface or the corner portion of the rectangular conductor can be further improved, and particularly the affinity between the conductor corner portion and the insulating coating can be increased, and sufficient film forming property can be imparted to the conductor corner portion. .

As a fourth aspect of the present invention, the lamp used for the ultraviolet irradiation treatment is a low-pressure ultraviolet lamp, and the wavelengths emitted from the lamp are 184.9 nm and 253.7.
It is a method for producing a flat insulated wire having a peak of nm. In the method of manufacturing a flat insulated wire according to the fourth aspect, a low-pressure ultraviolet lamp is preferable as the lamp used for the ultraviolet irradiation treatment, and the wavelength emitted from the lamp is 184.9n.
Those having a peak at m, 253.7 nm are preferable.

A fifth aspect of the present invention is a method for producing a flat insulated wire, wherein the wettability of the entire surface or corners of the ultraviolet-irradiated intermediate is 50 dyne / cm ² or more in terms of solid surface tension. In the method for producing a flat insulated wire according to the fifth aspect, since the wettability of the entire surface or the corner portion of the intermediate body subjected to the ultraviolet irradiation treatment is 50 dyne / cm ² or more in terms of solid surface tension, the entire surface or the corner portion of the intermediate body is obtained. The wettability of the intermediate product can be further improved, and particularly, the affinity between the corner portion of the intermediate body and the insulating coating can be increased, and the film forming property is sufficiently imparted to the corner portion of the intermediate body.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The contents of the present invention will be described below in more detail with reference to the embodiments shown in the drawings. The present invention is not limited to this. FIG. 1 is a chart showing one embodiment of a method for manufacturing a rectangular insulated wire of the present invention.

-First Embodiment (Example 1) -A method for manufacturing a rectangular insulated wire of Example 1 will be described with reference to the chart of FIG. First, a round copper wire (φ0.70 mm) was rolled to manufacture a rectangular conductor having a conductor thickness of 0.30 mm and a conductor width of 1.30 mm. (Rolling step f1) After annealing the above rectangular conductor, plasma treatment was performed on the entire surface of the rectangular conductor using a plasma irradiator ST-7000 (product name manufactured by Keyence Corporation). (Plasma treatment process f2) Next, using an electrothermal baking furnace with a linear speed of 8 m / min and a furnace temperature of 360 ° C, polyurethane insulation paint WD4307-30%
In the process of coating and baking (Hitachi Chemical Co., Ltd. product) multiple times, an ultraviolet surface modifier SSP-8 (product name of Sen Engineering Co., Ltd.) was used for the intermediate product with a film thickness of 0.004 mm on the rectangular conductor. Then, the corners of the intermediate body were selectively subjected to ultraviolet irradiation treatment, and further subjected to ultraviolet irradiation treatment and coating baking a plurality of times so that the coating thickness became 0.012 mm, to produce a rectangular insulated wire. (Paint coating baking / UV irradiation processing step f
3) During the production of the flat insulated wire, a sample of the flat conductor subjected to the plasma treatment was sampled and the wettability of the whole flat conductor and the corner portion was measured. The surface tension was 60 mN / m or more. Further, when a sample of the intermediate body subjected to the ultraviolet irradiation treatment was taken and the wettability of the entire surface and corner portions of the intermediate body was measured, the solid surface tension was 50 dyne / cm ² or more. The lamp used for the ultraviolet irradiation treatment is a low-pressure ultraviolet lamp, and the wavelength of light emitted from the lamp is 184.9n.
m, 253.7 nm has a peak.

-Comparative Example 1-Rolled copper wire (φ0.70 mm) has a conductor thickness of 0.30 mm and a conductor width.
Using a 1.30 mm flat conductor, after annealing, plasma treatment and ultraviolet irradiation treatment were not performed, and coating and baking were performed under the same conditions as in Example 1 except for the above, to produce a flat insulated wire.

-Characteristic Test- The flat insulated wires obtained in Example 1 and Comparative Example 1 were subjected to a pinhole test and a dielectric breakdown voltage test (metal cylinder method) according to JIS C3003 enamel copper wire and enamel aluminum wire test methods. I went. The results are shown in Table 1 below.

[0014]

[Table 1]

As is apparent from Table 1 above, the rectangular insulated wire obtained by the method for producing a rectangular insulated wire of the present invention is
It can be seen that, compared with the rectangular insulated wire of the comparative example, the pinhole and the dielectric breakdown voltage value are very excellent in spite of the thin insulating film thickness.

[0016]

According to the method for producing a rectangular insulated wire of the present invention, by rolling a round conductor into a rectangular conductor and then performing a plasma treatment, the entire rectangular conductor or selectively the rectangular conductor corner portion is wetted. Since the property is improved, the affinity between the corner of the conductor and the coating material is increased, and the film forming property is imparted to the corner of the conductor. Further, in the coating and baking step, the wettability of the entire surface of the intermediate body or selectively the corner portions is improved by irradiating the intermediate body with ultraviolet rays without hitting the insulating film. As a result, an insulating film having excellent adhesion is uniformly formed over the entire surface including the corners, the conductor surface is not exposed, and a flat insulated wire having excellent insulation properties can be obtained. Therefore, the reliability of the coil wound by using the flat insulated wire obtained by the present invention has also been greatly improved. Therefore, the present invention is extremely effective in contributing to the industry.

[Brief description of drawings]

FIG. 1 is a chart showing an embodiment of a method for producing a rectangular insulated wire of the present invention.

Claims (5)

[Claims] 1. A method for producing a rectangular insulated wire, which comprises applying an insulating coating to an outer periphery of a rectangular conductor a plurality of times and baking it to form an insulating coating having a predetermined coating thickness. A rolling step of rolling into a rectangular conductor; and a plasma processing step of plasma-treating the rectangular conductor to improve the wettability of the entire conductor surface or selectively the conductor corner portion;
And applying an insulating coating to the outer periphery of the plasma-treated flat rectangular conductor a plurality of times to form an insulating coating with a predetermined coating thickness. Is applied to the entire surface of the intermediate body or selectively to improve the wettability of the corners of the intermediate body. Method for manufacturing flat insulated wire. 2. The method for producing a rectangular insulated electric wire according to claim 1, wherein the rectangular conductor is copper, aluminum, or copper clad aluminum. 3. The method for producing a rectangular insulated wire according to claim 1, wherein the wettability of the entire surface or the corner portion of the plasma-treated flat conductor is 60 mN / m or more in terms of surface tension. 4. A low-pressure ultraviolet lamp is used as the lamp for the ultraviolet irradiation treatment, and the wavelengths emitted from the lamp have peaks at 184.9 nm and 253.7 nm. 3. The method for producing a flat insulated wire according to 3. 5. The flat angle according to claim 1, 2, 3 or 4, wherein the wettability of the entire surface or corners of the intermediate treated with ultraviolet irradiation is 50 dyne / cm ² or more in terms of solid surface tension. Insulated wire manufacturing method.