JPH05182831A - Thin film coil and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a thin film coil having a high volumetric ratio, excellent efficiency and an excellent yield and a manufacturing method thereof. CONSTITUTION:An aluminum plate is used and the aluminum plate is subjected to electrolytic oxidation treatment in the shape of coil, thereby forming an insulation portion 2 with alumite and the rest is a thin film coil which serves as a conductor portion of the coil. This construction makes it possible to provide a thin film coil which is high in terms of its volumetric ratio and conversion efficiency and excellent in terms of its yield.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film coil used for a stator of a small motor for driving a tape of a tape recorder, a video tape recorder or the like.

[0002]

2. Description of the Related Art In recent years, thin film coils used for stators of small motors have been changed from so-called plated coils to coils formed by winding fine magnet wire having a circular cross section.

As shown in FIG. 6, a plating coil which constitutes a stator portion of a small motor generally used in a tape recorder, a video tape recorder, etc., has a thickness of about 50 μm formed by plating a copper plate 24 with a partial copper. In general, two thin film coils 12 are laminated with an electrically insulating adhesive 25 to have a thickness of 100 μm, and further, the above coils are laminated as needed to form a coil according to a required current capacity.

The structure of a conventional thin-film coil will be described below with reference to the drawings. As shown in FIG. 6, the copper-plated copper wire 11 formed by pattern-plating copper on the copper plate 24 has a cross section of about 50 μm in both the horizontal and vertical directions. For example, in a motor used for a stator of a small tape drive motor used in a tape recorder called a headphone stereo, the required current capacity cannot be obtained with one layer of the plating coil, and the plating coil is coated with the electrically insulating adhesive 25. 12
Are laminated so as to face each other in two layers to form a coil 12, and two more coils 12 are laminated to form a unit 13 which is attached to a film 14. Further, a coil, which is the same as the unit 13 and is laminated by four layers, is electrically shifted by 90 ° and is attached to the opposite side of the film 14 (not shown) to form the stator 15 shown in FIG. 7. A magnet 16 is fixed to a yoke 17 so as to face the stator 15, and the yoke 17 is fixed to a shaft 18. The shaft 18 is rotatably assembled between a thrust bearing 19 and a radial bearing 20.

When the small motor having the above structure is energized, the rotor 21 is rotated by the magnetic force generated in the stator 15, and the torque is transmitted to the tape drive gear (not shown) via the belt 23 set on the drive pulley 22. It

[0006]

With such a conventional plated coil, the manufacturing method is difficult and the defective rate is high. In particular, in a plating coil that forms a conductive part having a width of 50 μm and an insulating part having a width of 50 μm, a rare short circuit due to contact between the conductive parts during the plating growth process or a foreign substance in the plating solution is deposited on the conductive part to cause a short circuit. In some cases, the cutting rate is high and the defective rate is as high as 20 to 60%. Therefore, mass productivity is significantly reduced, and the unit price per unit is increased. In addition, the cross-sectional shape of the plating coil tends to widen upward, and the space between the conductive part and the insulating part must be set based on the above-mentioned cross-sectional shape. There was a problem that could not be improved.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a thin-film coil having a low defect rate and excellent productivity, which replaces the conventional plated coil.

[0008]

In order to achieve the above object, the present invention comprises a conductive portion formed of an aluminum plate,
A thin film coil is mainly composed of an insulating portion formed by electrolytically oxidizing the aluminum plate into a coil shape.

Further, a resist resin is pattern-printed on the aluminum side of a clad plate obtained by laminating an aluminum plate and a copper plate, the exposed aluminum portion is electrolytically oxidized to alumite, and then the resist resin and the copper plate are removed by pickling to remove the portion. The thin film coil is manufactured by forming an aluminum plate that is anodized.

[0010]

According to this structure, since the insulating portion is formed in the conductor by chemical formation, there is no problem that the conductor grows and comes into contact with the coil, and the coil is short-circuited. A thin film coil can be provided. Further, according to this manufacturing method, it is possible to easily manufacture a small-sized and lightweight thin-film coil having a low defect rate in the manufacturing process and excellent productivity.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A thin film coil according to an embodiment of the present invention will be described below with reference to the drawings. 1 to 5 show the structure of the thin film coil of this embodiment. As shown in FIG.
Is aluminum, and the insulating portion 2 between the conductive portion 1 and the conductive portion 1 is
Is composed of anodized aluminum.

In the thin film coil having this structure, the thickness of the insulating portion 2 is set larger than that of the conductive portion 1. In order to obtain this structure, first, as shown in FIG.
A different metal of the copper plate 4 and the copper plate 4 is prepared as the clad plate 5. Next, as shown in FIG. 2, pattern printing of the resist resin 6 is performed on the aluminum plate 3. At this time, the resist resin is also coated on the copper plate on the back side of the clad plate 5. The clad plate 5 treated in this way is energized in an alumite treatment liquid (for example, a 10% sulfuric acid aqueous solution) to perform an alumite treatment.

When the alumite treatment is performed, the insulating portion 2 grows vertically as alumite crystals in the depth direction of the aluminum plate as shown in FIG.
To form.

At this time, the alumite forming the insulating portion 2 vertically penetrates in the depth direction of the aluminum plate and at the same time, grows upward. After the alumite treatment, the resist resin 6 is removed by washing (FIG. 4). The copper plate 4 is also removed by a step such as pickling, and only the alumite-treated aluminum plate remains.

Therefore, the insulating portion 2 is convex upward from the surface of the aluminum plate because the alumite treatment vertically grows vertically on the aluminum plate. Two thin film coils are superposed on each other with the surfaces of the alumite-processed portions in contact with each other being in contact with each other (FIG. 5).

When two thin film coil units are stacked and abutted against each other, the insulating material resistance between the two thin film coils can be sufficiently secured in the alumite portion 2, so that even if the adhesive is 2 to 3 μm, sufficient electrical insulation is guaranteed. You can

[0017]

As is apparent from the above description of the embodiments, according to the present invention, the thin film coil formed by subjecting the aluminum plate to the alumite treatment has an applied current capacity due to the effective spacing of the insulating portion. Aluminum is 60% of copper
However, it is possible to form a sufficiently thin coil. Since the thin film coil is completed only by the alumite treatment as described above, it is possible to provide a thin film coil having a high yield and excellent productivity.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a thin film coil original plate according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a pattern printing process of the resist resin.

FIG. 3 is a cross-sectional view showing the alumite treatment process.

FIG. 4 is a cross-sectional view showing the structure of the thin film coil.

FIG. 5 is a cross-sectional view showing a state in which two thin film coils are laminated in layers.

FIG. 6 is a sectional view showing the structure of a conventional thin-film coil.

FIG. 7 is a cross-sectional view showing a configuration of a motor using the thin film coil.

[Explanation of symbols]

 1 Conductive Part 2 Insulating Part 3 Aluminum Plate 4 Copper Plate 5 Clad Plate 6 Resist Resin Layer

[Procedure amendment]

[Submission date] September 22, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

[0009] resist resin was pattern-printed on the aluminum side of the clad formed by laminating an aluminum plate and iron plate, aluminum exposed portion electrolytic oxidation by alumite reduction, then removed the resist resin and iron plate with a strong acid, partially A thin film coil is manufactured by forming an aluminum plate that has been anodized.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

In the thin film coil having this structure, the thickness of the insulating portion 2 is set larger than that of the conductive portion 1. In order to obtain this structure, first, as shown in FIG.
And providing a dissimilar metal of the iron plate 4 as a clad plate 5. Next, as shown in FIG. 2, pattern printing of the resist resin 6 is performed on the aluminum plate 3. Previously coated with a resist resin to the back side of the iron plate on at this time clad plate 5. The clad plate 5 treated in this way is energized in an alumite treatment liquid (for example, a 10% sulfuric acid aqueous solution) to perform an alumite treatment.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

At this time, the alumite forming the insulating portion 2 vertically penetrates in the depth direction of the aluminum plate and at the same time, grows upward. After the alumite treatment, the resist resin 6 is removed by washing (FIG. 4). Iron plate 4 is also removed in the process, such as a strong acid washing <br/>, only aluminum plate anodized remains.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] Explanation of code

[Correction method] Change

[Correction content]

[Description of symbols] 1 conductive portion second insulating portion 3 aluminum plate 4 iron plate 5 clad plate 6 resist resin layer

[Procedure correction 6]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (2)

[Claims] 1. A conductive portion formed of an aluminum plate,
A thin film coil mainly composed of an insulating portion formed by electrolytically oxidizing the aluminum plate into a coil shape. 2. A resist resin is pattern-printed on the aluminum side of a clad plate obtained by laminating an aluminum plate and a copper plate, the exposed aluminum portion is electrolytically oxidized to alumite, and then the resist resin and the copper plate are pickled to remove the portion. Of manufacturing a thin film coil for forming an aluminized aluminum plate.