JPS63106979A - Magnetic disk device - Google Patents

Abstract

(57) [Abstract] 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, and particularly to a magnetic disk device for preventing off-track of a magnetic head when performing high-density recording.

[Conventional technology]

In a movable head type magnetic disk drive, a magnetic head is positioned at a desired track on a magnetic disk surface by servo control. Note that herein, the servo head and the data head will be collectively referred to as a magnetic head. An access mechanism is composed of a head mechanism section that supports the magnetic head and a drive mechanism section that moves it back and forth and fixes it. The function of the access mechanism is to precisely position the magnetic head at the desired position in the shortest possible time, and for this purpose the drive mechanism includes a voice coil (linear motor) motor (also called an actuator).
is often used. That is, when there is a request to retrieve specific information on the magnetic disk surface, the magnetic head needs to move rapidly in the radial direction of the magnetic disk in order to shorten the retrieval time. Therefore, a relatively high output voice coil motor is used as a head driving voice coil motor for moving and positioning the magnetic head.

However, when the high-output voice coil motor fixed to the base performs rapid operation in response to a calling command, the rapid acceleration/deceleration control generates a balance machine, which causes the carriage supporting the magnetic head to vibrate, and the base The magnetic disk also vibrates, causing the magnetic disk drive to go off-track.

Furthermore, the frame on which the magnetic head assembly is mounted also vibrates due to this reaction force, causing discomfort to the user.

This problem is becoming increasingly important as recording density increases. Conventionally, a disk device described in Japanese Patent Publication No. 51-48049 has been known as a device for improving such problems of vibration and balance generation. With this device,
The magnetic circuit part of the voice coil motor is made into a movable structure to absorb the balance.

In other words, the voice coil motor is provided with two running paths,
One is mechanically coupled to the transducer support to form a movable transport assembly and the other is coupled to the stator of the motor to form a stationary mounting structure. In addition, a balance absorber is provided to stop residual crawling motion of the stator.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional technology, since the device has a movable structure for heavy objects, the device becomes large and complicated, and sufficient consideration is not given to dust generated from the movable parts. Furthermore, since the magnetic circuit moves, the relative relationship between the magnetic disk and the magnetic head is different, making it difficult to accurately position the magnetic head.

SUMMARY OF THE INVENTION An object of the present invention is to solve these conventional problems and provide a magnetic disk device that can absorb vibrations generated during acceleration and deceleration of a voice coil motor and has a compact and highly reliable structure.

[Means for solving problems]

To achieve the above object, a magnetic disk device of the present invention includes a magnetic head for writing and reading information on a magnetic disk, and a voice coil motor for moving and positioning the magnetic head. ,
The present invention is characterized in that the magnetic disk, the magnetic head, and the voice coil motor are fixed to a base, and the base is attached and fixed to the chassis with a spring made of a superelastic alloy in the same direction as the moving direction of the voice coil motor.

[For production]

In the present invention, the magnetic circuit that receives a reaction force and the base are fixed to the voice coil motor, which is the original movable part, and the entire magnetic disk device is made of superelastic alloy in the same direction as the voice coil motor. Secure it to the chassis with the spring. When the actuator suddenly accelerates or decelerates, the reaction force is first generated in the magnetic circuit section, and this is transmitted to the base that is connected and fixed to the magnetic circuit section.
The entire device is subjected to a reaction force. This reaction force causes the entire device to move in a direction opposite to the direction of movement of the actuator. This movement is absorbed by a spring that utilizes the plastic deformation region characteristics of a superelastic alloy (for example, a Ni-Ti alloy).

〔Example〕

EMBODIMENT OF THE INVENTION Below, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a characteristic diagram of the superelastic alloy used in the present invention. Superelastic alloys (e.g. N i -T i )
has the characteristics of the stress/strain curve as shown in FIG. 2.The properties of the zero elastic region 10 are the same as those of general metals, but the feature of this material is the plastic region 11. In other words, in the case of general metals, when the strain (load) is increased to the plastic region,
Although the strain remains, in a superelastic alloy, as shown in FIG. 2, when the load is removed, the deformation strain disappears and the alloy returns to its original state. In other words, if this alloy is used in the plastic range, it will result in a spring that has a very small spring constant and generates sufficient force. As described above, by using this as a spring for absorbing the movement of the device, it becomes possible to suppress the movement of the disk device at a low resonance frequency, so that the reaction force of the movement of the voice coil motor can be absorbed.

FIG. 1 is a cross-sectional structural diagram of the inside of a magnetic disk device showing an embodiment of the present invention. 1 is a chassis that supports a magnetic disk device; 2 is a superelastic alloy spring used in this embodiment; 3 is a base that fixes a voice coil motor, a magnetic disk, and a magnetic head; 4 is a magnetic disk disk; 5 is a chassis that supports a magnetic disk device;
1 is a magnetic head attached to the carriage, 6 is a magnetic circuit inserted into the middle of the voice coil motor 7, 8 is a coil of the voice coil motor 7, and 9 is a guide means for moving the base 3.

Magnetic disk drive [i! 3 is freely attached to the moving direction of the voice coil motor 7 by a guide means (roller) 9, and is fixed to the chassis 1 with a superelastic alloy spring 2.

In a magnetic disk device, a magnetic head 5 is attached to a voice coil motor 7, and the magnetic head 5 is linearly driven by the voice coil motor 7 and a magnetic circuit 6 in order to randomly access the magnetic disk 4 on which data is written. . When the voice coil motor 7 is driven toward the center of the magnetic disk 4, the base 3 moves in the opposite direction, compressing the superelastic spring on the magnetic circuit 6 side and extending the spring on the magnetic disk side. Since the spring 2 attempts to return to its original state, the magnetic disk becomes an initial state and is ready for primary driving.

Conventionally, a vibration-absorbing movable structure was provided inside the device, but in this embodiment, a vibration-absorbing movable structure is provided outside the device, so there are no problems such as dust generation, and reliability is improved. A high quality magnetic disk device can be realized.

〔Effect of the invention〕

As explained above, according to the present invention, since the magnetic disk device is fixed with a superelastic alloy spring in the moving direction of the voice coil motor, it is possible to absorb vibrations generated during acceleration and deceleration of the voice coil motor. It is possible to realize a very small and inexpensive high-density magnetic disk device.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional structural diagram of a magnetic disk device showing an embodiment of the present invention, and FIG. 2 is a characteristic diagram of a superelastic alloy used in the present invention.

Claims (1)

[Claims] 1. In a magnetic disk device equipped with a magnetic head that writes and reads information on a magnetic disk, and a voice coil motor that moves and positions the magnetic head, the magnetic disk, the magnetic head, and the voice coil motor are combined. A magnetic disk drive, characterized in that it is fixed to a base, and the base is attached and fixed to a chassis with a spring made of a superelastic alloy in the same direction as the moving direction of the voice coil motor.