JPH06231937A - Flat-wire coil - Google Patents

Abstract

PURPOSE:To realize uniform thickness, to improve dimensional accuracy, to improve driving force and operational accuracy and to realize resistance to insert molding by winding flat wire by a specified method. CONSTITUTION:A flat-wire coil 1 is formed of an upper coil 1a and a lower coil 1b formed by winding an insulated flat wire 2 so that a cross sectional contour thereof forms a square. The upper coil 1a and the lower coil 1b are constituted of one flat wire 2 provided with a folded part 3 at an inner peripheral side of the coil. Both end parts 4a, 4b of the flat wire 2 project to an outer peripheral side of the coil 1, the flat wire 2 is wound not to deviate in a width direction and the folded part 3 does not project to both side surfaces of the flat wire 1. Thereby, it is possible to acquire a coil having a uniform thickness, high dimensional accuracy and enough strength.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rectangular wire coil formed by winding an insulating coated rectangular wire, and more particularly to a rectangular wire coil useful as a movable coil for moving a magnetic field detector of a hard disk.

[0002]

2. Description of the Related Art As a movable coil for moving an actuator or a carriage used in a magnetic disk device equipped with a magnetic head, an air-core coil formed by winding several layers of electric wire having a circular section has been generally used. Has been used for. In such a conventional coil, an electric wire coated with a fixing adhesive is wound into a predetermined size and further pressed to be fixed.

However, in such a conventional movable coil, there is a drawback that the wound electric wire is misaligned and the thickness of the coil is apt to become uneven, resulting in poor dimensional accuracy.

By the way, such a movable coil is usually incorporated in an actuator or a carriage, and the actuator or the carriage is operated by interaction with an electromagnet or a permanent magnet arranged in the vicinity of the movable coil. Therefore, the smaller the gap between the movable coil and the magnet, the more efficiently the driving force can be obtained.

However, if the thickness of each coil is not uniform as in the above-mentioned conventional moving coil, the gap between the moving coil and the magnet cannot be made very small, and there is a limit to the improvement of the driving force. Further, since the conventional moving coil cannot obtain sufficient dimensional accuracy, it is not sufficient to improve the operating accuracy of the actuator or the carriage by the moving coil.

Further, when the movable coil is incorporated in the actuator or the carriage by insert molding, the conventional movable coil has a problem that the coil is deformed by the pressure of filling the thermoplastic resin and the parallelism cannot be maintained.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and has a uniform thickness and a high dimensional accuracy, and the driving force and operation accuracy when operating an actuator or the like. It is an object of the present invention to provide a coil useful as a movable coil, which can improve the above-mentioned property and can sufficiently endure insert molding.

[0008]

As a result of intensive studies to achieve the above object, the present inventors have used a strip-shaped conductor wire (a rectangular wire) instead of the conventionally used electric wire, and The inventors have found that a coil capable of solving the above problems can be obtained by winding in a specific method, and have reached the present invention.

That is, the flat wire coil according to the present invention is a flat wire coil formed by winding a flat wire which has been insulation-coated.
It is characterized in that the rectangular wire is wound so that both ends thereof are located on the outer peripheral side of the coil and both side surfaces of the coil are not uneven.

[0010]

The flat wire can be wound accurately without being displaced laterally like a conventional electric wire, so that a coil having a uniform thickness can be easily and surely obtained. Therefore, the rectangular wire coil of the present invention has a high dimensional accuracy, and when it is incorporated in an actuator or a carriage and arranged close to the magnet, the gap between the coil and the magnet can be made extremely small.

Further, since both ends of the rectangular wire are on the outer peripheral side of the coil, it is easy to connect with a power source or the like when used as a movable coil.

Furthermore, since the rectangular wire has a particularly strong strength in the width direction, the rectangular wire coil of the present invention does not deform even when it is incorporated into an actuator or a carriage by insert molding.

[0013]

EXAMPLES The present invention will be described in more detail based on the following examples, but the examples are not intended to limit the scope of the present invention but show preferred modes of the present invention.

FIG. 1 is a perspective view showing a preferred example of the rectangular wire coil of the present invention. 2 and 3 are similar to FIG.
FIG. 3 is a perspective view showing a state in the middle of manufacturing the rectangular wire coil. 1-3, 1 is a rectangular wire coil, 1a is an upper coil, 1b is a lower coil, 2 is a rectangular wire, 3
Is a folded portion, and 4a and 4b are both ends of a rectangular wire.

The flat wire coil 1 of the present invention shown in FIG. 1 is a coil of two upper and lower layers obtained by winding a flat wire 2 having an insulating coating (not shown) so as to have a quadrangular cross section, that is, an upper coil. 1a and the lower coil 1b, and the upper coil 1a and the lower coil 1b are the folded portions 3 on the inner circumference side of the coil.
It is composed of one rectangular wire 2 through. In the flat wire coil 1 configured as described above, both ends of the flat wire 2
4a and 4b are exposed on the outer peripheral side of the coil. Also, the rectangular wire 2
Is wound so that it does not shift in the width direction, and the folded-back portion 3 and the like do not project on both side surfaces (upper surface and lower surface) of the rectangular wire coil 1, so both side surfaces are flat and the coil 1 has a uniform thickness. Is.

The rectangular wire coil 1 is obtained, for example, as follows. That is, as shown in FIG.
The upper coil 1a is formed by winding so as not to shift in the width direction and to have a rectangular cross-sectional shape. Next, the rectangular wire 2 inside the upper coil 1a is folded back at a right angle, and the rectangular wire 2 is folded again at a right angle in the lateral direction as shown in FIG. 3 (folded portion 3). In this way, the rectangular wire 2 inside the upper coil 1a is displaced parallel to the lower side of the upper coil 1a. Then, the flat wire 2 is wound so that the flat wire 2 is not displaced in the width direction and has a quadrangular cross-sectional shape to form the lower coil 1b.
Is obtained.

The rectangular wire coil 1 thus obtained
Are fixed by a fixing adhesive or the like as necessary. The fixing may be performed by winding a rectangular wire and then applying an adhesive resin or the like to fix it, or by winding a rectangular wire to which an adhesive resin or the like is applied in advance and then fixing it. Further, the insulation coating of the rectangular wire may be performed with an insulating adhesive resin or the like.

The method of winding the flat wire in the flat wire coil of the present invention is not particularly limited to the above-described method, and the flat wire is placed on both side surfaces of the coil so that both ends thereof are located on the outer peripheral side of the coil. May be wound so that no unevenness occurs.
The cross-sectional shape of the flat wire coil of the present invention is preferably a quadrangular shape as shown in FIG. 1, but the shape is not limited to this and other shapes such as a circular shape and a triangular shape may be used. Further, the structure of the folded portion is not particularly limited to the above.

Further, in this embodiment, the rectangular wire coil composed of the upper and lower two layers of coils is exemplified, but the number of layers is not limited to two.
Further, the structure may be such that the number of layers is increased. In addition, when connecting each layer via a folding | turning part as mentioned above, an even number of layers is preferable.

Next, the case where the rectangular wire coil 1 of the present invention as described above is used as a movable coil of an actuator will be described.

An example of a swing type actuator in which the rectangular wire coil 1 of the present invention is incorporated as a movable coil is shown in FIG.
Shown in. Further, FIG. 5 shows a state in which the movable coil of the swing type actuator is arranged between the magnets. Figure 4-
In FIG. 5, 1 is a movable coil (rectangular wire coil), 5 is an arm, 6 is a yoke, 7 is a pillar, 8 is a permanent magnet, 9 is a void portion, and 10 is an axis.

The swing type actuator shown in FIG. 4 has an arm 5 made of aluminum die cast or the like.
And a movable coil (rectangular wire coil) 1. When the movable coil 1 is fixed to the arm 5, an adhesive is used, or it is joined by insert molding with a thermoplastic resin. Even in the case of insert molding, the rectangular wire coil of the present invention is not deformed by the pressure of filling the thermoplastic resin.

The moving coil 1 is, as shown in FIG.
When the movable coil 1 is energized by being disposed in the space 9 sandwiched between the permanent magnets 8 indicated by the yoke 6 and the support 7, a driving force around the shaft 10 acts on the movable coil 1 to cause the shaft 10 to move.
Swing around.

Since the rectangular wire coil 1 of the present invention has a uniform thickness and high dimensional accuracy as described above, the movable coil 1
The gap between the permanent magnet 8 and the permanent magnet 8 can be made sufficiently small. Therefore, in the actuator using the rectangular wire coil 1 of the present invention, the above-mentioned driving force can be efficiently obtained, and the operation accuracy is improved.

[0025]

As is apparent from the above description, the rectangular wire coil of the present invention has a uniform thickness and high dimensional accuracy. Further, the rectangular wire coil of the present invention has a strength sufficient to withstand insert molding when it is integrated with other members.
Therefore, by using the rectangular wire coil of the present invention as a movable coil for operating an actuator or the like, it is possible to make the gap between the movable coil and the magnet very narrow, thereby improving the driving force and the operating accuracy. It can be greatly improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a preferred example of a rectangular wire coil of the present invention.

FIG. 2 is a perspective view showing a state in the middle of manufacturing the rectangular wire coil of FIG.

FIG. 3 is a perspective view showing the next state of FIG. 2 in manufacturing the rectangular wire coil of FIG. 1.

FIG. 4 is a schematic plan view showing an example of a swing type actuator in which the rectangular wire coil of the present invention is incorporated as a movable coil.

5 is a schematic cross-sectional view showing a state where a movable coil of the swing type actuator of FIG. 4 is arranged between magnets.

[Explanation of symbols]

1: Flat wire coil (moving coil), 1a: Upper coil, 1
b: lower coil, 2: rectangular wire, 3: folded portion, 4a, 4
b: both ends of the rectangular wire, 5: arm, 6: yoke, 7: strut, 8: permanent magnet, 9: void, 10: axis.

Claims (2)

[Claims] 1. A rectangular wire coil formed by winding an insulating coated rectangular wire, wherein the rectangular wire has concavities and convexities such that both ends thereof are on the outer peripheral side of the coil and both side surfaces of the coil are uneven. A rectangular wire coil characterized by being wound so as not to occur. 2. The rectangular wire coil according to claim 1, wherein the rectangular wire is wound so as to have a rectangular cross section.