JPH02155453A - voice coil motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a voice coil motor suitable for head drive devices of various disk devices.

[Prior Art] A voice coil motor is often used as an active device for a magnetic head in a magnetic disk device such as a hard disk device, or as an active device for an optical pickup in an optical disk device.

FIG. 6(a) is a plan view showing a conventional example of such a voice coil motor, and FIG. 6(b) is a sectional view taken along the line A--A. In these figures, a voice coil motor 1 constitutes an active device of a magnetic head (not shown), and a top plate 101 and a bottom plate 102 are connected to side plates 103 and 1.
It is fixed via 04. On the inner surface of the upper plate 101,
Magnets 105 and 106 whose planes are substantially fan-shaped are fixed,
Similarly, on the inner surface of the bottom plate 102, magnets 107.10
8 is fixed. Top plate 101. The bottom plate 102 and the side plates 103 and 104 are each made of a magnetic material and form a magnetic circuit.

And magnets 105, 106 and magnet 107
, 108, the coil 10 is formed into a fan shape within the gap between the coils 10
9 are arranged. One end of this coil 109 is fixed to a support 110. The support body 110 is rotatably attached to a shaft 111 fixed to the device frame (not shown) via a bearing.

Further, a magnetic head (not shown) is fixed to the tip of the arm 112 fixed to the support 110.

The voice coil motor 1 configured as described above is, for example, as shown in FIG.
The bottom plate 102 is fixed on the base frame 201. In addition, in this case, the upper cover 202 of the box body 2
In order to prevent the upper cover 202 from being incompletely attached due to contact with the upper plate 101, a certain gap d is formed between the two.

[Problem to be solved by the invention, 1] Incidentally, in recent years, magnetic disk drives have been made smaller, but in the past, the above-mentioned parts were indispensable to configure the voice coil motor l. there were. In addition, in order to drive the magnetic head with constant torque over a certain range,
Magnets 105-108 required a certain surface area and thickness.

Therefore, in order to arrange the voice coil motor 1, a space with a height of h2 and a width of 1 or more in the moving direction of the coil 109 is required within the box body 2. The width of the sheath was also restricted, making it difficult to downsize the device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a voice coil motor that solves the above problems and allows the device to be made smaller.

[Means for Solving the Problems] For this purpose, the present invention directly fixes and supports a magnetic circuit member, which is a magnet or a magnetic material, on a device box body, and removes the supporting member, while also supporting the magnetic circuit member. This is characterized in that the box itself is made of a magnetic material and forms part of a magnetic circuit.

[Function] By directly fixing and supporting the magnetic circuit member to the device box, there is no need for a supporting member and there is no need to provide extra space, and the voice coil motor can be formed into a car shape. , it becomes possible to downsize the device. Moreover, by forming the box body from a magnetic material, an efficient magnetic circuit can be constructed.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cutaway perspective view of a cartridge type magnetic disk device according to an embodiment of the present invention, and FIG.
A vertical sectional view taken along the line B. In the figure,
The same reference numerals as in FIG. 6 indicate the same parts, and the box 2 of the magnetic disk device is formed of a base frame 201 and an upper cover 202 that covers the base frame 201 from above. Both the base frame 201 and the upper cover 202 are made of a magnetic material such as iron.

Inside the box body 2, there is a magnetic disk cartridge 3 at the front.
is attached, and a boil coil motor 4 is disposed at the rear. A magnetic disk 301 is housed inside the magnetic disk cartridge 3 .

In the boil coil motor 4, a substantially fan-shaped upper plate 401 made of a magnetic material is fixed to the lower surface of the upper cover 202, and on the upper surface of the base frame 201 opposite to this,
A bottom hole 402 made of the same material and having the same shape is fixed. Also,
Magnets 105 and 106 are fixed to the bottom surface of the top plate 401, and magnets 107 and 108 are fixed to the top surface of the bottom plate 402.
are each fixed.

Regarding the polarity of the magnets 105 and 107, the upper surfaces thereof are north poles, and the upper surfaces of magnets 106 and 108 are south poles. As a result, the gap between the magnets 105 and 107 forms a magnetic field of upward magnetic flux, and the gap between the magnets 106 and 108 forms a magnetic field of downward magnetic flux. Arm 112
A magnetic head 203 is fixed to the tip.

On the other hand, although not shown in Figure 1, there is a magnetic head 203 inside the box body 2.
Accordingly, a data processing circuit for recording and reproducing data on the magnetic disk 301, a head drive control circuit for driving the magnetic head 203, and the like are provided.

With this configuration, when recording and reproducing information, this magnetic disk device uses the head ridge movement section to move the coil 109.
A direct current is applied to the The magnetic field generates torque in the coil 109, drives the support 110 in a certain direction, and the magnetic head 203 moves toward the magnetic disk 309.
move onto the data track. Also, at this time, a predetermined servo control is executed to control the energizing current according to the moving position of the magnetic head 203, so that the magnetic head 203 is positioned at a desired track position and information is recorded and reproduced. Become.

As described above, in this embodiment, the upper plate 401 constituting the boil coil motor 4 is directly fixed to the upper cover 202, so while the gap d in FIG. 7 is eliminated, the upper plate 401 is supported. The side plate 103, 1, which is a member that was
04 is no longer necessary.

As a result, the space required within the box body 2 to arrange the boil coil motor 4 is reduced by the above-mentioned gap d and the thickness of the side plates 103 and 104, such as height h2 and width V2. Accordingly, it becomes possible to form the device thinner, narrower in width, and smaller in size.

Now, FIG. 3 shows another embodiment of the present invention. In the above embodiment, the magnets 105 and 106 are fixed to the upper cover 202 through the upper plate 401, and the magnets 107 and 108 are fixed to the base frame 2 through the bottom hole 402.
However, as shown in the figure, each magnet 105 to 108 is fixed to the base frame 20.
1 and the upper cover 202, respectively.

With this configuration, the height of the required space inside the box body 2,
Thus, it is possible to further reduce the thickness by the thickness of the top plate 401 and the bottom plate 402.

Further, FIG. 4 shows another embodiment, in which two magnets 113 and 114 are provided, while
The thickness of each magnet 105 to 108 in Fig. 3 is a
In this case, the thickness of the magnets 113 and 114 is 2
It is set to a.

As a result, it is possible to theoretically apply a magnetic flux of the same intensity to the coil 109 as in the case of FIG.
A voice coil motor equivalent to that of the above embodiment can be constructed in a space with the same height as that of the above embodiment.

Next, FIG. 5 shows still another embodiment of the present invention. In FIG. and an upper cover 502, in which a linear motor 6, which is a type of voice coil motor, is disposed as a head operating device.

The traveling body 601 connects the magnetic head 20 via an arm 602.
3 is fixed and is slidably disposed in the theta direction of the magnetic disk 301. Coils 602 and 603 are fixed to both sides of the traveling body 601. Each coil 6
02,603 is a base frame 501 and an upper cover 50
It is fitted into H-shaped yokes 604 and 605 that are fixed to 2.

Furthermore, magnets 6 are located at the positions of the yokes 604 and 605 of the base frame 501 and the upper cover 502, respectively.
06 to 609 are fixed. In addition, in the same figure,
Magnet 607 is not shown.

Since the base frame 501 and the upper cover 502 are made of magnetic material, these members and the yoke 604
, 605 and the magnets 606 to 609 form a magnetic circuit.

With this configuration, the magnetic head 203 moves onto a predetermined track on the magnetic disk 301 by energizing the coils 602 and 603. Then, the energizing current is adjusted by predetermined servo control, the magnetic head 203 is positioned at a fixed position, and information is recorded and reproduced.

In this way, in this embodiment, the base frame 501 and the upper cover 502 are made of magnetic material, and the yoke 60 is attached to them.
4, 605 and magnets 606 to 609 are directly fixed to form the linear motor 5.

This eliminates the need to separately provide a yoke for fixing the magnets 606 to 609 and its supporting member.
The space required for arranging the linear motor 5 can be reduced, and the device can be downsized.

Note that in each of the above embodiments, the base frame 201.5
01 and the upper covers 202, 502 are made of magnetic material, but the coil 109°6 can be made of magnetic material.
02.603, so it does not necessarily have to be a magnetic material.

In addition, in FIG. 5, the yokes 604 and 605 are formed in an H shape to support the insertion portions of the coils 602 and 603, but the insertion portions are directly connected to the base frame 5.
01 or the upper cover 502 to support it, it can be made even smaller.

[Effects of the Invention] As described above, according to the present invention, the magnetic circuit member, which is a magnet or a magnetic material, is directly fixed to and supported by the device box, which eliminates the need for supporting members and saves unnecessary parts. This eliminates the need for additional space and allows the voice coil motor to be formed into a car shape, making it possible to downsize the device. On the other hand, by forming the box body from a magnetic material, it is possible to create an efficient magnetic circuit. Can be configured.

[Brief explanation of the drawing]

FIG. 1 is a cutaway perspective view of a magnetic disk device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line B-B in FIG.
3 is a vertical cross-sectional view of a magnetic disk device according to another embodiment of the present invention, FIG. 4 is a vertical cross-sectional view of a magnetic disk device according to another embodiment of the present invention, and FIG. 5 is a vertical cross-sectional view of a magnetic disk device according to another embodiment of the present invention. FIG. 6 is a plan view of a conventional voice coil motor and a vertical sectional view taken along the line A-A, and FIG. 7 is a vertical sectional view of a magnetic disk device according to another embodiment. It is a sectional view showing an arrangement state. 1... Voice coil motor, 2, 5... Box body, 3.
... Magnetic disk cartridge, 4... Voile coil motor, 6... Linear motor, 101,401...
・Top plate, 102,402... Bottomless, 105-108,
113,114,606-609...Magne! -1
109,602,603-:Iil, 201,501-
...Base 7L/-m, 202.502...Top cover, 601...Traveling body, 604,605...Yoke. Figure 1 Figure 3 Figure 2 Figure 4---1--1-Wx-← Figure 6Q-Figure

Claims (2)

[Claims] (1) Electricity is applied to a coil disposed inside the box of various devices in the gap of a magnetic circuit composed of a magnetic circuit member made of a magnet or magnetic material, and the coil is moved by electromagnetic force in a direction that crosses the magnetic flux. 1. A voice coil motor for moving a voice coil motor, characterized in that the magnetic circuit member is directly fixed to and supported by the box body, and a member for supporting the magnetic circuit member is removed. (2) The voice coil motor according to claim 1, wherein the box body is formed of a magnetic material and constitutes a part of the magnetic circuit.