JPS63201976A - magnetic disk device - 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 magnetic disk device that linearly moves an actuator assembly that supports a magnetic head.

[Prior Art] As shown in FIG. 4, a conventional magnetic disk device of this type includes a holding mechanism 2 that holds a magnetic disk 1, an actuator assembly 4 that supports a magnetic head 3, and the actuator assembly. It is equipped with a drive mechanism 5 for linearly moving the solid body 4, a base 6 as a fixing member for fixing the drive mechanism 5 and the holding mechanism 2, and a housing 8 in which the base 6 is disposed via a vibration damping member 7. It is composed of

The holding mechanism 2 includes a spindle motor and a mounting member for mounting the magnetic disk 1 on the spindle of the motor, and rotates the magnetic disk 1 by driving the spindle motor. The actuator assembly 4 includes a head arm 42 to which the magnetic head 3 is attached via an elastic arm member 41 to one end, and a carriage 44 to which the other end of the head arm 42 is attached and which can run on a traveling guide 43. have. The drive mechanism 5 includes a base 6
a permanent magnet 51 fixed to the actuator assembly 4;
A moving coil 52 attached to a carriage 44 constitutes a voice coil motor, and a magnetic circuit is formed by the permanent magnet 51 and the moving coil 52, so that the moving coil 52 moves linearly. .

The base 6 has a hollow shape, and a spindle motor of the holding mechanism 2 and a permanent magnet 51 of the drive mechanism 5 are fixed to the inner bottom of the base 6. The housing 8 has a hollow shape large enough to surround the base 6, and the base 6 is disposed at a predetermined position inside the housing 8 via a vibration damping member 7. The vibration damping member 7 is made of an elastic body such as rubber.

In the magnetic disk device, when the magnetic disk 1 is rotated by the holding mechanism 2, a magnetic circuit is formed between the permanent magnet 51 and the moving coil 52 of the drive mechanism 5, and the moving coil 52 moves, thereby moving the actuator assembly 4 in a straight line. move it,
In this manner, the magnetic head 3 scans the magnetic disk 1 in the radial direction to write and read data. Also.

When a reaction force is generated on the base 6 when the actuator assembly 4 is driven, or when an external force is applied to the housing 8 in the moving direction of the actuator assembly 4 or in the same direction, the resulting vibrations are absorbed by the vibration damping member 7. Attenuation by the spring force reduces vibrations to the base 6 and prevents the positioning accuracy of the magnetic head 3 from deteriorating. Therefore, the vibration generated in the base 6 is suppressed as much as possible by setting the spring constant and damping coefficient of the vibration damping member 7 so as not to resonate with other parts.

In addition, related to this type of device.

For example, Japanese Unexamined Patent Publication No. 59-210577 can be cited.

[Problems to be Solved by the Invention] By the way, in the prior art in which the actuator assembly 4 moves linearly as shown above, the base 6 as a fixed member
When an external force acts on either of the housing 8 and the housing 8 in the same direction as the movement direction of the actuator assembly 4, compared to a so-called swing type in which the actuator assembly rotates around a fulcrum, the following There is a problem to mention.

In other words, in the case of a swing type, even if vibration occurs in the base due to the drive of the actuator assembly, it is a rotational vibration, so the vibration is made so that the nodes of the vibration coincide with the center of rotation of the actuator assembly. By selecting the position and spring constant of the damping member, vibration can be suppressed to a level that satisfies the specifications without any problems.

However, in the prior art, since the actuator assembly 4 is linearly driven, linear vibration occurs in the base 6. Therefore, even if the spring constant and damping coefficient of the vibration damping member 7 and the mounting position are changed, It was not possible to position the magnetic head with high precision to a level that satisfied the specifications, and as a result, the recording density was increased.

There is a problem that it cannot support high-speed access.

Furthermore, in order to solve the above problem, it is conceivable to increase the weight of the permanent magnet 51, base 6, etc. of the drive mechanism 5 to reduce the reaction force itself against the base 6 that is generated when the actuator assembly 4 is driven. But if you do that,
There is a problem that the drive mechanism becomes large and is restricted under the demand for miniaturization.

In view of the problems of the prior art, it is an object of the present invention to reliably reduce vibration and position a magnetic head with high precision without increasing the size of the drive mechanism or fixing member, thereby achieving high recording density and high-speed access. An object of the present invention is to provide a magnetic disk device that can respond to miniaturization and miniaturization.

[Means for Solving the Problems] In the present invention, when the inner wall of the casing comes into contact with the fixing member and an external force acts on either the fixing member or the casing in the direction of movement of the actuator assembly. A friction surface is provided that can suppress the relative displacement between one side and the other.

[Operation] When a reaction force is generated in the drive mechanism due to the driving of the core actuator assembly, the force is transmitted to the fixed member, which may cause the fixed member to vibrate and reduce the positioning accuracy of the magnetic head.

However, as described above, when the fixing member comes into contact with the inner wall surface of the casing and an external force is applied to either the fixing member or the casing, the relative displacement between one and the other can be suppressed. Since the friction surface is provided, the fixed member vibrates while rubbing against the friction surface of the casing, and the amount of displacement of the fixed member is suppressed, thereby damping the vibration of the fixed member. .

On the other hand, when an external force acts on the casing in the same direction as the movement direction of the actuator assembly, the fixed member vibrates through the casing, but the friction surface of the casing rubs against the fixed member and vibrates. , the vibration of the housing can be damped by suppressing the amount of displacement of the housing.

As a result, vibrations can be damped by the friction surface, and the friction surface and the vibration damping member disposed within the housing work together to achieve a remarkable vibration damping effect.

Vibrations occurring in the fixed member can be reliably reduced, and the magnetic head can be positioned with high precision. Furthermore, since it is sufficient to simply form a friction surface on the inner wall of the casing, there is no need to increase the size of the drive mechanism or fixing member. Therefore, it has the effect of being able to sufficiently cope with higher recording density, higher speed access, and smaller size.

[Examples] Examples of the present invention will be described below with reference to the accompanying drawings. 1st
The figure is a cross-sectional side view showing one embodiment of the present invention, and FIG. 2 is an explanatory side view showing the basic principle of the present invention.

As shown in FIG. 1, the magnetic disk device of the embodiment includes a holding mechanism 2 that holds a magnetic disk 1, an actuator assembly 4 that supports a magnetic head 3, and a drive mechanism that linearly moves the actuator assembly 4. 5, a base 6 as a fixing member for fixing the drive mechanism 5 and the holding mechanism 2, and a casing 8 in which the base 6 is disposed via a vibration damping member 7. This point is similar to the conventional example.

One difference between the present invention and the conventional example is this.

As shown in FIG. 2, when the base 6 comes into contact with the inner wall of the casing 8 and an external force is applied to either the base 6 or the casing 8 along the moving direction X of the actuator assembly 4. The point is that a friction surface 9 is formed that can suppress the relative displacement amount between the base 6 and the housing 8.

That is, as shown in FIG. 1, the friction surface 9 is formed on the inner wall of the bottom of the housing 8 to protrude upward with a certain length and width so as to come into contact with the bottom surface of the base 6.
It forms a flat surface along the bottom of the. When the drive of the actuator assembly 4 generates a reaction force on the permanent magnet 51 of the drive mechanism 5, and linear vibration occurs in the base 6, the base 6 vibrates while rubbing against the friction surface 9.

When linear vibration is generated by suppressing the amount of displacement of the base 6 and applying an external force to the housing 8 in the moving direction or the same direction as the actuator assembly 4, the friction surface 9 will rub against the base 6. At the same time, it vibrates and suppresses the amount of displacement of the casing 8, thus reducing vibrations generated in the base 6 via the permanent magnet 51 of the drive mechanism 5 or the casing 8. Therefore, the friction surface 9 has an appropriate frictional force so as to suppress the amount of relative displacement between the casing 8 and the base 6 in response to vibrations of either one of them.

Note that in FIGS. 1 and 2, the same parts as in the conventional example are given the same reference numerals.

Next, the operation of the magnetic disk device of the embodiment will be described.

When a reaction force is generated in the drive mechanism 5 due to the drive of the actuator assembly 4, vibration is generated in the base 6, which may reduce the positioning accuracy of the magnetic head 3. However, the base 6 is in contact with the inner wall of the casing 8, and the base 6
Since a friction surface 9 that can suppress the relative displacement between the base 6 and the housing 8 is provided, the base 6 vibrates while rubbing against the friction surface 9, and the displacement of the base 6 is suppressed. By doing so, vibrations occurring in the base 6 can be damped.

In some cases, when an external force acts on the housing 8 in the moving direction of the actuator assembly 4 or in the same direction as the actuator assembly 4, the base 6
There is a risk that vibration will occur and the positioning accuracy of the magnetic head 3 will decrease. However, the vibration of the housing 8 and the base 6 can be damped by suppressing the amount of displacement of the housing 8 because the housing 8 vibrates while rubbing against the base 6 due to its friction surface 9. .

As a result, vibrations can be damped by the friction surface 9, and the friction surface 9 and the vibration damping member 7 disposed within the housing 8 together provide a significant vibration damping effect, so that the actuator assembly 4 Even if an external force acts in the same direction as the moving direction X of the magnetic head 5, the vibration generated in the base 6 can be reliably reduced, and the magnetic head can be positioned with high precision.

Further, since it is sufficient to form the friction surface 9 on the inner wall portion of the housing 8, it is not necessary to make the drive mechanism 5 or the base 6 large.

Note that FIG. 3 is an explanatory diagram comparing the vibration waveforms of the embodiment of the present invention and the conventional example. In the same figure.

A shows the vibration waveform of the embodiment, B shows the vibration waveform of the conventional example,
From this figure, the vibration damping effect of the example is clear.

[Effects of the Invention] As described above, according to one aspect of the present invention, a friction surface is provided on the inner wall of the casing that comes into contact with the fixing member and can suppress the relative displacement between the fixing member and the casing. , when an external force is generated on either the fixed member or the housing in the same direction as the moving direction of the actuator assembly, the vibration generated in the fixed member can be damped by the friction surface, and the friction surface and the vibration damping member are Together, they have a remarkable vibration damping effect, can reliably reduce the vibration of the fixed member, and can position the magnetic head with high precision, making it possible to support higher recording density, faster access, and miniaturization. . −

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional side view showing one embodiment of the present invention. Fig. 2 is an explanatory diagram showing the basic principle of the present invention, Fig. 3 is an explanatory diagram comparing the vibration waveforms of an embodiment of the present invention and a conventional example, and Fig. 4 is a cross-sectional side view showing an example of a conventional configuration. It is a diagram. DESCRIPTION OF SYMBOLS 1... Magnetic disk, 2... Holding mechanism, 3... Magnetic head, 4... Actuator assembly, 5... Drive mechanism, 6... Base (fixing member), 7... Vibration damping member, 8... Housing, 9... Friction surface.

Claims (1)

[Claims] 1. A holding mechanism that holds a magnetic disk, an actuator assembly that supports a magnetic head, a drive mechanism that linearly moves the actuator assembly, a fixing member that fixes the drive mechanism and the holding mechanism, and a fixing member that fixes the drive mechanism and the holding mechanism. In a magnetic disk drive including a casing disposed inside the casing via a vibration damping member, the actuator assembly is in contact with a fixing member on the inner wall of the casing and is attached to either the fixing member or the casing. A magnetic disk drive characterized by being provided with a friction surface capable of suppressing the relative displacement between one side and the other when an external force is applied in the direction of movement.