JPH0273574A - Coil assembly for positioning carriage of magnetic disk device - Google Patents

Abstract

PURPOSE:To enhance the radiating effect for the heat of a coil by forming coil bobbins out of metallic material, keeping insulatability, sandwiching a coil between the coil bobbins, bonding and fixing it. CONSTITUTION:Coil bobbins 12 and 13 are formed out of the metallic material, the storage part for a coil 11 is recessed and formed, and a slit 14 for eddy current is formed in a part corresponding to a coil sandwiching part. By fixing a coil assembly 10, whose coil bobbins are formed out of the metallic material, on the side of a housing having a magnetic head with screws, etc., like this, the heat by the rise of the temperature of the coil 11 is transmitted from the coil 11 to the coil bobbins 12 and 13 with large thermal conductivity, to the housing, and radiated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement of a coil assembly suitable for use in a positioning carriage of a magnetic disk device.

[Conventional technology]

Conventionally, in the positioning carriage of this type of magnetic disk drive, as soon as there is a request to read specific information on the magnetic disk, the movable head must be rapidly positioned in the radial direction of the magnetic disk so as to minimize the read time. Must be.

4 and 5(a) and 5(b) show a positioning carriage in a rotary type magnetic disk drive as a conventional example, and in these figures, reference numeral 1 in FIG. 4 is a magnetic head. These magnetic helads 1 are attached to the tip of an arm 3 extending from the housing 2. 4 is a bearing 5a.

The rotating shaft 4 rotatably supports the housing 2 via a pair of bases 6a.

It is supported between 6b. Then, the magnetic disk 1 is moved to an appropriate position on a magnetic disk (not shown), and magnetic data is written and read as the magnetic disk rotates.

A voice coil motor coil assembly (hereinafter referred to as a coil assembly) 7 is provided in a part of the pair of bases 6a and 6b. This coil assembly 7 is shown in FIG. 5(a).
, (b), it consists of a coil 7a and a coil bobbin 7b, and by extending the current to the coil 7a, the permanent magnet assembly 8 and the coil 7a interposed between the bases 6a and 6b. A force is generated between the two, and the magnetic helad 1 is rotationally displaced by this force. Here, in the coil assembly 7 used as a positioning carriage in such a conventional device, the coil bobbin 7b is generally used.
The coil 7a is made of a synthetic resin material such as phenol resin, and the coil 7a is made of AM or Cu wire.

[W1B to be Solved by the Invention] By the way, in the above-mentioned conventional device, in the coil assembly 7 for the positioning carriage, in order for the magnetic helad 1 to perform a rapid operation in response to a command such as a call, it is usually necessary to
A fairly large current of about 5 A was applied. For this reason, the temperature of the coil 7a rises rapidly when energized, and the temperature of the coil bobbin 7b also rises accordingly.As a result, the amount of elongation between the coil 7a and the coil bobbin 7b increases due to the difference in linear expansion coefficients. Because of the difference, a problem may arise in which the coil 7a peels off from the coil bobbin 7b.

Further, since the material of the coil bobbin 7b is a synthetic resin material, gas is generated due to the above-mentioned heat, which may have a serious effect on the magnetic head and the magnetic disk that is the recording medium.

The present invention has been made in view of the above circumstances, and provides a coil assembly for a positioning carriage of a magnetic disk device, which can eliminate the conventional problems caused by heat generation due to energization as described above. The purpose is to obtain.

[Means to solve the problem]

In order to meet such demands, the coil assembly for a positioning carriage for magnetic disk storage according to the present invention has a coil bobbin made of a metal material, and a state in which the coil is sandwiched between the coil bobbin while maintaining an insulated state. These are then fixed with adhesive.

[Effect]

According to the present invention, a coil assembly is formed by sandwiching and adhesively fixing a coil between coil bobbins made of a metal material while maintaining an insulated state.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

1(a), (b), (c) and FIG. 2 show an embodiment of a coil assembly for a positioning carriage of a magnetic disk device according to the present invention, and in these figures, the above-mentioned Components that are the same as or correspond to those in FIGS. 4 and 5 are given the same numbers and their explanations will be omitted.

Now, according to the present invention, the coil bobbin 12 is used as a coil assembly lO for a positioning carriage of a magnetic disk device.
．． 13 is made of a metal material, and the coil 11 is sandwiched between the coil bobbins 12 and 13 while maintaining an insulated state, and is then assembled with adhesive and fixed. .

Here, in this embodiment, among the coil bobbins 12.1, the pobbin 13 is formed into a substantially shallow dish shape, and the coil 11 housing portion is formed in a recessed manner.
3 is fixed to the side of the housing 2 having the magnetic helad l with screws or the like. Furthermore, a slit 14 is formed in a portion of the coil bobbin 12, 13 corresponding to the portion where the coil 11 is sandwiched, and this slit 14 is a cutout for preventing eddy current.

In such a configuration, when the coil assembly 10 is rapidly moved by a read or write command to the magnetic head 1, a large current flows through the coil 11 as described above.
This causes the temperature of the coil 11 to rise rapidly, but since the coil bobbin 12 and 13 are made of a metal material such as aluminum, the thermal conductivity is several hundred times higher than that of conventional synthetic resin materials. Largely, this results in heat generation being transmitted to the coil 11, the coil bobbin 12, 13 and the housing 2, and the heat being dissipated.

In addition, since the coil 11 is sandwiched between the coil bobbins 12 and 13 and fixed with adhesive, it exhibits approximately twice the heat conduction compared to conventional one-sided bonding.
The heat dissipation effect is high, and since these materials are metal materials having approximately the same coefficient of thermal expansion, there is no problem of peeling occurring at the bonded part. According to .13, it is also possible to suppress the generation of gas as in the conventional case.

Of course, what should be noted here is that the surface of the coil bobbin 12, 13 made of metal material should be insulated with hard alumite or the like to ensure insulation between it and the coil 11. With such a configuration, it is possible to ensure an appropriate and reliable insulation state, while preventing the coil wire material from being damaged by external physical forces, resulting in excellent strength.

3(a), (b), and (c) show another embodiment of the present invention. In this embodiment, a coil bobbin 15 having a substantially U-shaped cross section is used.
In addition, while the upper and lower surfaces of the coil 11 are adhesively fixed to the bobbin 15 side, a part of the coil 11 is exposed to the outside. It will be easily understood that approximately the same effect can be obtained. Here, reference numeral 16 in the figure is a cutout window.

Note that the present invention is not limited to the structure of the embodiment described above, and the shape, structure, etc. of each part of the magnetic disk device may be modified or changed as appropriate, and various modifications may be considered. The coil bobbin shape is only exemplified as a double coil bobbin shape, and the point is that the bobbin is made of a metal material and may be configured so that the coil can be covered from both sides, and various modifications can be considered.

〔Effect of the invention〕

As explained above, according to the coil assembly for the positioning carriage of a magnetic disk drive according to the present invention, the coil bobbin is formed of a metal material, and the coil is sandwiched between the coil bobbins while maintaining insulation properties. As the structure is simple and inexpensive, it has an excellent heat dissipation effect against the heat generated when the coil is energized, and also prevents peeling between the coil and the coil bobbin. It has various excellent effects, such as being able to prevent gas generation due to heat generation and damage to coils, etc.

[Brief Description of the Drawings] Figures (a), (b), and (c) are a schematic plan view, a front view, and a front view of an embodiment of a coil assembly for a positioning carriage of a magnetic disk device according to the present invention. The side view and FIG. 2 are schematic diagrams showing a schematic configuration of a magnetic disk device implementing a coil assembly according to the present invention. FIGS. 3(a), (b), and (c) are schematic diagrams showing another embodiment of the present invention, FIG. 4 is a schematic configuration diagram illustrating a conventional magnetic disk device, and FIG. 5(a), (b) is a schematic plan view and a front view illustrating a conventional coil assembly. 1...Magnetic head, 2...Housing, 3...
... Arm, 4 ... Rotating shaft, 10 ... Coil assembly, 11 ... Coil, 12, 13; 15 ...
Coil bobbin, 14...slit, 16...notch window. Figure 1 (a) 1 Figure 1 (b) 1 convex Figure 2 (C) Figure 3 (a) Figure 3 (C) Figure 3 (b)] 1 Figure 4 a 6a 5 Figure (a) b

Claims (1)

[Claims] In a coil assembly for a positioning carriage of a magnetic disk device, which has a coil for driving an arm that supports a magnetic head and a coil bobbin that supports the same, the coil bobbin is formed of a metal material, and the coil is insulated by the coil bobbin. A coil assembly for a positioning carriage of a magnetic disk device, characterized in that the coil assembly is adhesively fixed while being sandwiched in a sandwich-like state.