JPH0581847A - Method of operating magnetic disk device and magnetic disk device - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to a magnetic disk device used as an external storage device of a computer system, wherein a magnetic head records or reproduces information without floating from the magnetic disk, and further recording is performed. The purpose is to increase the density. [Structure] A magnetic disk 12 whose surface is coated with a lubricant,
A magnetic head 13 for recording and reproducing information on and from the magnetic disk 12, a shroud 16 for accommodating the magnetic disk 12 and the magnetic head 13, and a temperature inside the shroud 16 for the lubricant applied to the magnetic disk 12. The cooling device 17 for maintaining the temperature below the freezing point of 5 ° C. and above the freezing point of 5 ° C., and the magnetic head 13.
It has a head arm 14 and a rotary actuator 15 that support the surface of the rotating magnetic disk 12 so as to come into contact with the lubricant, and the lubricant is solidified so that it contacts the magnetic head 13 when recording or reproducing information. By melting the lubricant by the frictional heat generated by the magnetic head 13, the magnetic head 13 slides on the surface of the magnetic disk 12 through the melted liquid lubricant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of operating a magnetic disk device used as an external storage device of a computer system and a magnetic disk device.

With the enormous amount of information processing by computer systems, the capacity and size of magnetic disk devices have been increasing, and along with this, there has been a demand for higher density recording of magnetic disk devices. Has been done.

[0003]

2. Description of the Related Art In a conventional magnetic disk device, information is recorded and reproduced while a magnetic head is levitated from the surface of the magnetic disk. It is essential to reduce the flying height (gap) from the magnetic head.

However, as the flying height of the magnetic head is reduced, the magnetic head is more likely to come into contact with the surface of the magnetic disk, and damage caused by these contacts, so-called head crash, is more likely to occur.

In order to prevent the occurrence of head crush as much as possible, in the conventional CSS type magnetic disk device, a lubricant is applied to the surface of the magnetic disk to prevent the magnetic head from starting and stopping. The shock between and is moderated.

[0006]

However, in the conventional magnetic disk apparatus, there is a limit to reducing the flying height of the magnetic head in order to prevent the occurrence of head crash, and it is intended to increase the recording density. There was a limit above.

Further, since the magnetic head is levitated, there is a problem that there is a high possibility that a head crash will occur due to mechanical shock or electrical / thermal fluctuation applied to the magnetic disk device.

In view of the above problems, it is an object of the present invention to record or reproduce information without the magnetic head floating above the magnetic disk, and to further increase the recording density.

[0009]

In order to solve the above-mentioned problems, the operating method according to the first aspect of the present invention provides a magnetic disk 12 having a surface coated with a lubricant 31, as shown in FIGS. A method of operating a magnetic disk device, comprising: a magnetic head 13 for recording and reproducing information on the magnetic disk 12;
The lubricant 31 applied to the surface of the magnetic head 13 is kept solidified by being held in an atmosphere at a temperature below its freezing point, and the magnetic head 13 rotates the surface of the magnetic disk 12 at the time of recording or reproducing information. The magnetic head 13 is slid on the surface of the magnetic disk 12 through the lubricant which is melted into a liquid state by melting the lubricant 31 due to the frictional heat caused by the contact.

In the operating method according to the second aspect of the present invention, the lubricant 31 applied to the magnetic disk 12 is held in an atmosphere at a temperature below the freezing point and at least 5 degrees lower than the freezing point.

A magnetic disk device 1, 1a according to a third aspect of the present invention includes a shroud 16 for accommodating the magnetic disk 12 and the magnetic head 13, and the shroud 16.
Temperature adjusting devices 17, 19 for maintaining the internal temperature at a temperature below the freezing point of the lubricant 31 applied to the magnetic disk 12 and above the freezing point of 5 degrees.
And head supporting members 14 and 15 for supporting the magnetic head 13 so as to come into contact with the lubricant 31 on the surface of the rotating magnetic disk 12.

In the magnetic disk device 1, 1a according to the fourth aspect of the present invention, while the head support members 14, 15 are not maintaining the shroud 16 at a predetermined temperature by the temperature adjusting devices 12, 19, The magnetic head 1
3 is operated so as to hold the magnetic disk 3 in a non-contact state from the lubricant 31 applied to the magnetic disk 12.

[0013]

The temperature inside the shroud 16 is maintained at a predetermined temperature by the temperature adjusting devices 12 and 19, whereby the lubricant 31 is solidified.

When recording or reproducing information, the magnetic head 13 comes into contact with the lubricant 31 on the surface of the rotating magnetic disk 12, and the lubricant 31 is melted by frictional heat generated by the contact. As a result, the magnetic head 13 slides on the surface of the magnetic disk 12 through the lubricant that has been melted and turned into a liquid state.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional front view showing a main part of a magnetic disk device 1 according to the present invention. The magnetic disk device 1 includes a spindle 1 that is rotationally driven by a motor (not shown).
1, a plurality of magnetic disks 12 mounted on the spindle 11, a magnetic head 13 for recording and reproducing information on each magnetic disk 12, a head arm 14 for supporting each magnetic head 13, and a head arm 14. Supporting rotary actuator 15, shroud 1
6, a cooling device 17, a sensor 18, a control device (not shown), and the like.

The shroud 16 houses and seals the magnetic disk 12, the magnetic head 13 and the like. The temperature inside the shroud 16 is detected by a sensor 18, and the cooling device 17 keeps the temperature T1 within a certain range. Is adjusted.

The cooling device 17 is provided with a supply port 23 and a discharge port 24 for circulating the cooling water, and the cooling water supplied from the supply port 23 is the heat provided inside the cooling device 17. Cool the air through the exchanger. The air inside the shroud 16 is sucked through the suction port 21, the air is cooled and dried through the heat exchanger, and is blown out through the blowing port 22. The air blown out from the air outlet 22 recirculates inside the shroud 16 and maintains the temperature around the magnetic disk 12 at a temperature T1 in a certain range.

As will be described later, the temperature T1 is set in a range of T2-5 <T1 <T2 with reference to the freezing point T2 of the lubricant applied to the surface of the magnetic disk 12.

Further, the rotary actuator 15 is
The magnetic head 13 rotates to rotate the magnetic disk 12 by itself.
It is possible to perform a head seek by moving in the radial direction of the
The magnetic head 13 is held in a non-contact state with the surface of the magnetic disk 12 in a state where the range has not reached.

FIG. 2 shows a magnetic disk 12 and a magnetic head 1.
3 is an enlarged perspective view, and FIG. 3 is an enlarged cross-sectional view showing a contact state between the magnetic disk 12 and the magnetic head 13. The magnetic head 13 includes an electromagnetic conversion element 41 based on thin film technology and a slider 42 that holds the electromagnetic conversion element 41.

The slider 42 is supported by the head arm 14, and when the magnetic disk device 1 is stopped and the inside of the shroud 16 has not reached the set temperature T1 range, the magnetic head 13 moves to the surface of the magnetic disk 12. It is held so as to be in a non-contact state by withdrawing from (the surface of the lubricant 31), but in a state where it is held in the set temperature T1 range, it is kept in contact with the surface of the magnetic disk 12, and The head arm 1 prevents the magnetic disk 12 from flying even if an air flow or an air layer is generated by the rotation of the magnetic disk 12.
A suitable load is applied by 4.

The slider 42 itself is also shaped so that the angle of entry of the air flow is small so that it is difficult for the slider 42 to fly. A slider rail is formed in a portion that comes into contact with the lubricant 31.

On the surface of the magnetic disk 12, the freezing point is T
The lubricant 31 of 2 is applied thinly. During operation of the magnetic disk device 1, the magnetic disk 12 and the lubricant 31 are held in the temperature atmosphere of the temperature T1 described above by the cooling device 17, so that the lubricant 31 is solidified.

When the lubricant 31 is solidified, the magnetic head 13 comes into contact with the surface of the lubricant 31a, and then the magnetic disk 12 rotates. Therefore, the magnetic head 1
When information is recorded on or reproduced from the magnetic disk 12, the magnetic head 13 (or the slider 42) comes into contact with the lubricant 31a on the surface of the rotating magnetic disk 12, and lubricates by frictional heat generated by the contact. The agent 31a is melted, whereby the magnetic head 13 slides on the surface of the magnetic disk 12 through the lubricant 31a which has been melted into a liquid state.

Further, even when the head seek is performed, the portion of the lubricant 31a which is in contact with the magnetic head 13 is melted by frictional heat, so that the magnetic disk 12 is magnetized via the lubricant 31a in the liquid state. It slides on the surface of the disk 12 and moves.

In any case, when the magnetic head 13 passes over the magnetic disk 12, the portion of the lubricant 31a which is actually in contact with the magnetic head 13 is melted, and after the magnetic head 13 passes, the shroud is shrouded. Temperature T1 in 16
As a result, the lubricant 31a is solidified again and returns to the state before the passage.

Therefore, information is recorded or reproduced while the magnetic head 13 is in contact with the magnetic disk 12, so that the electromagnetic conversion characteristics of the electromagnetic conversion element 41 are improved and the recording density can be greatly increased. it can. Moreover, since the magnetic head 13 is in contact with the molten lubricant 31a, the sliding contact with the magnetic disk 12 is smooth, the magnetic disk 12 and the magnetic head 13 are not damaged, and a head crash occurs. Does not occur.

An example of the lubricant 31 is ethyl pentadecanoate. Ethyl pentadecanoate has a freezing point T2 of 14 degrees Celsius, and the temperature at which the coefficient of friction with the magnetic head 13 begins to decrease is 5 degrees lower than the freezing point T2. Therefore, the temperature T1 falls within the range of 9 to 14 degrees Celsius. It is preferable to set. However, it is more preferable to set the temperature in the range of 11 to 14 degrees Celsius in order to melt the lubricant 31 even with a slight temperature rise.

Rotating magnetic disk 12 (lubricant 31)
Due to the contact between the magnetic head 13 and the magnetic head 13, a temperature rise of about 1.5 degrees is actually measured. Ethyl pentadecanoate begins to liquefy at a temperature that is 2 to 3 degrees lower than the freezing point T2 and the coefficient of friction with the magnetic head 13 decreases, so if the atmospheric temperature in the shroud 16 is maintained as described above,
The contact sliding of the magnetic head 13 becomes smooth.

FIG. 4 is a sectional front view showing a main part of a magnetic disk device 1a according to another embodiment of the present invention. 4, parts having the same functions as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

In the magnetic disk device 1a, the shroud 1
A cooling container 19 is further provided on the outer periphery of 6, and a cooling water flow passage 20 is provided between them. Supply port 25
The cooling water supplied from the cooling water flows through the flow passage 20 and is discharged from the discharge port 26, while cooling the shroud 16 and keeping the inside of the shroud 16 within the set temperature T1 range.

Although the cooling water is used for cooling in the above-mentioned embodiments, other refrigerants may be used. Lubricant 31
Various materials other than ethyl pentadecanoate may be used. In that case, if the temperature T1 is higher than room temperature due to the freezing point T2 of the lubricant 31, heating is performed instead of cooling. Further, both the cooling device and the heating device may be used together.

In the above-described embodiments, a desiccant or a dedicated drying device may be used to dry the air inside shroud 16. Others, magnetic disk drive 1, 1
The configuration of a can be modified in various ways other than the above.

[0034]

According to the present invention, it is possible to further increase the recording density by recording or reproducing information without the magnetic head flying above the magnetic disk.

[Brief description of drawings]

FIG. 1 is a sectional front view showing a main part of a magnetic disk device according to the present invention.

FIG. 2 is an enlarged perspective view showing a magnetic disk and a magnetic head.

FIG. 3 is an enlarged cross-sectional view showing a contact state between a magnetic disk and a magnetic head.

FIG. 4 is a sectional front view showing a main part of a magnetic disk device of another embodiment according to the present invention.

[Explanation of symbols]

 1, 1a Magnetic disk device 12 Magnetic disk 13 Magnetic head 14 Head arm (head support member) 15 Rotary actuator (head support member) 17 Cooling device (temperature adjusting device) 19 Cooling container (temperature adjusting device) 31, 31a Lubricant

Claims (4)

[Claims] 1. A magnetic disk (12) having a surface coated with a lubricant (31), and a magnetic head (13) for recording and reproducing information on the magnetic disk (12). A method of operating a magnetic disk device comprising: a lubricant (31) applied to the magnetic disk (12).
Is kept in an atmosphere at a temperature below its freezing point to be solidified, and when recording or reproducing information, the magnetic head (13)
Is contacted with a lubricant (31) on the surface of the rotating magnetic disk (12), and the lubricant (31) is melted by frictional heat generated by the contact, whereby the magnetic head (13) is melted and the liquid A method of operating a magnetic disk device, comprising sliding on the surface of the magnetic disk (12) through the lubricant in the state described above. 2. The lubricant (31) applied to the magnetic disk (12) is kept in an atmosphere having a temperature below the freezing point and at a temperature 5 degrees lower than the freezing point or above. 2. A method of operating the magnetic disk device according to 1. 3. A magnetic disk (1) having a surface coated with a lubricant.
A magnetic disk device (1) (1a) comprising a magnetic head (13) for recording and reproducing information on and from the magnetic disk (12), 12) and the magnetic head (13)
And a temperature in the shroud (16) that is less than or equal to the freezing point of the lubricant (31) applied to the magnetic disk (12) and 5 degrees lower than the freezing point. And a head support member for supporting the magnetic head (13) in contact with the lubricant (31) on the surface of the rotating magnetic disk (12). A magnetic disk drive comprising (14, 15). 4. The head support member (14, 15) is maintained while the shroud (16) is not kept at a predetermined temperature by the temperature adjusting device (17) (19).
The magnetic disk drive according to claim 3, wherein the magnetic head (13) is operated so as to be kept in a non-contact state from the lubricant (31) applied to the magnetic disk (12).