JPS6143781B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic disk storage device, and more particularly to a magnetic disk storage device that can attenuate mechanical resonance of a head positioning mechanism and stabilize a servo system.

One of the requirements for the moving part of a servo-controlled, voice coil motor type magnetic head actuator (hereinafter simply referred to as an actuator), which is generally used in magnetic disk storage devices, is to increase the bandwidth of the position servo loop. The goal is to create a structure that can be made as wide as possible. The first purpose of doing this is to reduce the time (settling time) required for the actuator to completely settle to a predetermined track position after a seek operation, and the second purpose is to This is to maintain high positioning accuracy even if there is vibration caused by internal force (reaction force of the actuator itself).

Now, when designing a structure with the required broadband vibration characteristics in this way, the resonance point that becomes a problem is, for example, 2 KHz or higher, which is high for a mechanical structure of this level. In addition, since there are many elements that make up a vibration system and they are connected in a complex three-dimensional manner, it is extremely difficult to design by hand calculation. Even if the solution is solved by .etc., more experimental approaches are required. Furthermore, mechanical vibration systems designed in this way also have variations in characteristics due to manufacturing and assembly variations, such as variations in screw tightening force, which may require reassembly or parts replacement during the manufacturing process. Occurs often. As described above, conventional magnetic disk storage devices suffer from difficulties in vibration-proof design, assembly and component variations.
It was not possible to set mechanical resonance characteristics, and it was difficult to maintain high positioning accuracy.

As a way to solve this problem, Utility Model 54-130408
As shown in the above publication, it has been proposed to mount a damping mass of a constant mass on a voice coil motor of a magnetic disk device equipped with a linear actuator so that it can move freely. However, this damping mass can only be used with linear actuators, and since the damping mass and voice coil motor frequently operate in three-dimensional directions while in frictional contact, dust is generated and the disk is damaged. Prepare for the possibility of adversely affecting the recording surface.

An object of the present invention is to eliminate the above-mentioned problems, and to provide a magnetic disk storage device that can attenuate the mechanical resonance of the head positioning system, absorb manufacturing variations, and obtain stable characteristics. The goal is to provide the following.

A feature of the present invention is that a damping mechanism consisting of a plurality of damping balls arranged in a closed space is provided on the voice coil motor of a magnetic disk storage device, and the base is elastically held via a damper. This is to absorb vibrations caused by the actuator.

An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a magnetic disk storage device equipped with a linear actuator, which is an embodiment of the present invention.

As shown in the figure, the magnetic disk storage device according to the present invention includes a base that supports a disk disk 4 fixed to a spindle 5 and a voice coil motor (consisting of a coil bobbin 7 and a magnet 6) that linearly drives a carriage 8. 1 is configured to be vibrationally independent from the main base 2 by a damper 3. Furthermore, a damping mechanism 10 is mounted on the base 1 to absorb vibrations of the base 1.

The principle of the damping mechanism 10 in this embodiment is, as shown in FIG. 2, composed of a damping mass 30 having a predetermined mass, a spring 10a holding the damping mass 30, a dash pot 10b, and a friction damper 10c. Further, these damping mechanisms are covered with a dustproof cover 40. As a result, the drive generated in the base 1 and transmitted to the damping mass 30 is absorbed by the spring 10a, the dart pot 10b, and the friction damper 10c. The first specific example of this damping mechanism is shown in the third example.
As shown in the figure.

The damping mechanism 10 shown in FIG. 3 is configured such that a hollow cylindrical damping mass 30a, which is covered with a dustproof cover 40 and closed at one end, is mounted on the base 1 with a screw 20 via a spring 10a. . This damping mass 30a is connected to the spring 10a.
It is movable in the vertical direction with damping properties, and is also movable in the lateral direction through the hole 31 having a diameter that is larger than the diameter of the screw 20.

As a second specific example of the damping mechanism 10,
As shown in FIG. 4, a convex damping mass 30
screws 20 are attached to both ends of b through springs 10a. In this case as well, the hole in the damping mass 30b through which the screw 20 passes is given a sufficient diameter so that the damping mass 30b can move laterally. This damping mechanism is also covered by a dustproof cover.

Furthermore, as a third specific example of the damping mechanism, as shown in FIG. It consists of a damping mass 30c attached to the other end of the spring 10a'.

In addition, the damping mechanism shown in FIG. 6a is such that a damper 10b' made of rubber or the like is provided on the upper part of the leaf spring 10a' to strengthen the damping property.
The damping mechanism shown in FIG. 1 has an additional leaf spring 10c' attached to the attachment portion of the leaf spring 10a' to the base 1 to enhance frictional damping properties. The mass of the damping mass is suitably about 1/3 of the mass of the magnet 6, or about 4 times the mass of the movable part.

Furthermore, another specific example of the damping mechanism will be explained using FIG. 7. This damping mechanism has an inner diameter of 17 mm, for example, at the base end of the magnetic disk storage device.
A cylindrical hole with a height of 70 mm is provided, a plurality of lead balls 14 (damping balls) each having a diameter of 3 mm (approximately 150 g) are inserted into the hole, and a dustproof cover 13 covers the hole. The vibration motion is absorbed by the movement of the lead ball 14 within the hole.

The operation of an embodiment of the present invention based on the above configuration will be described in detail below. The vibration of the voice coil motor that occurs when the magnetic disk storage device shown in FIG.
Absorbed by 0.

This vibration absorption is achieved by, for example, damping masses 30a and 30b shown in FIGS. 3 and 4, which move behind the movement of the magnet 6 due to inertia force, and furthermore, move back and forth and left and right due to frictional force. This is achieved by moving up and down against the force of a spring with a striking action.

Further, in the damping mechanism shown in FIGS. 5 and 6, the excitation motion is absorbed by the movement of a damping mass 30c provided at the end of the leaf spring 10a'. Incidentally, since the hole in the leaf spring 10a' that is screwed to the base 1 by the screw 21 is sufficiently larger than the diameter of the screw 21, the leaf spring 10a' can move to some extent in the front, back, left and right directions.

Therefore, the excitation action of the magnet 6 is canceled out, making it possible to maintain high head positioning accuracy.

In the description of the embodiments of the present invention, a linear actuator type magnetic disk storage device has been described, but the present invention provides the damping mechanism at the base end of a rotary actuator type magnetic disk storage device. It can be carried out even if it is difficult.

Furthermore, by mounting the damping mechanism on the rotary actuator, the vibration motion of the actuator can be absorbed. This will be explained below using FIGS. 8 to 10. The rotary actuator type magnetic disk storage device shown in the figure includes a voice coil motor consisting of a magnet 6 and a coil bobbin 7, a head arm 9 to which the voice coil motor is connected, and a head arm 9.
and a carriage block 12 rotatably supporting a voice coil motor and a voice coil motor. Further, a damping mechanism 10 is provided on the carriage block 12 of each rotary actuator to absorb the vibration motion of the actuator. This damping mechanism 1
The specific structure of 0 is as described above in FIGS. 3 to 7.

The disk disk 4 is accessed by the rotary actuator by applying electric power to the coil bobbin 7 and driving the voice coil motor to rotate the head arm 9 about the rotation axis. In this case, vibrations generated by the rotary actuator are absorbed by the movement of damping masses 30a, 30b, and 30c in the damping mechanism 10 provided on the carriage block 12, making it possible to perform highly accurate head positioning. can. In this case, dust particles generated due to, for example, frictional contact between the base 1 and the damping mass are blocked by the cover 40 that covers the damping mass.

When the damping mechanism including lead balls shown in FIG. 7 is mounted on an actuator, it is constructed by including a plurality of lead balls 14, which are damping balls, in a box-shaped container 90, as shown in FIG. 11.

As described above, according to the present invention, a magnetic disk storage device with high positioning accuracy can be provided by absorbing the vibrations generated by the actuator by the damping mechanism provided on the base or carriage block.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a magnetic disk storage device as an embodiment of the present invention, and FIG. 2 is a diagram showing the principle of the damping mechanism shown in FIG. 1. 3 to 7 are diagrams showing embodiments of the damping mechanism according to the present invention,
8 to 10 are diagrams showing a rotary actuator type magnetic disk storage device which is another embodiment of the present invention. FIG. 11 is a diagram showing an embodiment of the damping mechanism. Explanation of symbols, 1... Base, 2... Main base, 3... Damper, 4... Disk, 5...
Spindle, 6... Magnet, 7... Voice coil, 8... Carriage, 9... Head arm,
10... Damping mechanism, 10a... Spring, 10
b and 10c...damper, 40...dustproof cover, 20, 21, 22...screw, 30, 30a,
30b, 30c...damping mass, 13...dustproof cover, 14...lead ball.

Claims (1)

[Claims] 1. In a magnetic disk storage device in which a rotationally driven disk disk and a linear actuator for accessing the magnetic head to the disk disk are integrally mounted on a base, a voice coil constituting the linear actuator A magnetic disk storage device characterized in that a damping mechanism comprising a plurality of damping balls arranged in a closed space is provided on the motor, and the base is elastically held via a damper.