JP2003303402A - Information recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the reliability of a magnetic disk device. <P>SOLUTION: In a magnetic disk device provided with an air pressure detection section, a magnetic disk, and a magnetic head slider, the data area of the magnetic disk is limited based on the detected information of the air pressure detection section. The writing operation of a magnetic head in a data area in which contact between the magnetic head slider and the magnetic disk is easy is prevented, and thus the reliability of the magnetic disk device is improved. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording device.

[0002]

2. Description of the Related Art A magnetic disk apparatus records information on a magnetic disk or a magnetic disk while a magnetic head slider having a magnetoresistive effect element (MR element) mounted thereon is levitated above the surface of the magnetic disk. It is a device for reading the information stored in.

The magnetic head slider flies over the surface of the magnetic disk at intervals of about 10 to 20 nm, and is designed so that the magnetic head slider and the magnetic disk do not come into contact with each other in a general use environment. In the actual manufacturing, the magnetic head slider is confirmed by the flying height measuring device whether or not the set flying height is maintained.

Also, in the magnetic disk, it has been confirmed by an inspection device equipped with a head with a contact detection sensor that no protrusion having a height higher than a preset height is present in the surface of the magnetic disk. This set height is usually one of the flying heights of the magnetic head slider.
/ 2, specifically 7 to 10 nm.

The flying height of these magnetic disks may change when the atmospheric pressure changes, and a magnetic disk device which takes measures against the change is proposed in Japanese Patent Laid-Open Nos. 6-150522 and 2001-283549. Has been done.

[0006]

With the increase in recording density,
The flying height of the magnetic head slider of the magnetic disk device is 1
It is becoming as narrow as 0 to 20 nm. The flying height is determined by the viscosity and velocity of the air flow generated when the magnetic disk rotates. Since the magnetic disk device rotates while maintaining a certain number of rotations, the flying height of the magnetic head slider is lower on the inner peripheral side than on the outer peripheral side by the speed.

On the other hand, on the magnetic disk side, the actual allowable contact height is 7 to 10n due to the undulations and surface roughness of the disk.
It is about m. Further, since the magnetic head slider and the magnetic disk are process products, there are some manufacturing variations. Therefore, the margin of contact between the magnetic head slider and the magnetic disk is only about several nm.

A personal computer equipped with a magnetic disk device has been used in various environments because of its rapid miniaturization and generalization. Notebook PCs are often used in airplanes and are also actively used in high altitude areas.

In an airplane or in a high altitude area, the atmospheric pressure is lower than that in a flat environment. When the altitude increases by 1000 m, the atmospheric pressure decreases by about 0.1 atm (about 100 hPa). When the atmospheric pressure decreases, the viscosity of the air flow decreases, so that the flying height of the magnetic head slider decreases. In the case of the magnetic head slider currently used, it has been confirmed that the flying height decreases by 0.7 to 1 nm as the altitude increases by 1000 m.

If the magnetic disk device has a contact allowance margin of only about 2 to 3 nm due to variations in manufacturing and is used in a high altitude environment, the head flying height is reduced and the magnetic head slider and the magnetic disk are likely to come into contact with each other. Become. In particular, even in a flatland environment, the contact rate is high on the inner circumference side where the flying height is originally low.

When the magnetic head slider contacts the magnetic disk, the magnetic head slider vibrates. This vibration causes a so-called misalignment in which writing cannot be performed at a predetermined track position particularly when writing a record.

An object of the present invention is to easily avoid the contact problem of the information recording apparatus due to the pressure drop in a high altitude environment and improve the reliability of the apparatus.

[0013]

The basic feature of the information recording apparatus according to the present invention is to limit the recordable data area area of the disc based on the detection information of the atmospheric pressure detecting section. An information recording device by grasping the advanced use environment based on the detection information of the atmospheric pressure detection unit and avoiding the write / read head write operation in the data area where the write / read head slider and the disk easily come into contact with each other. The reliability of can be improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1A and 1B are schematic views of the inside of a magnetic disk device, and FIG. 2 is a schematic view for explaining how a magnetic head slider flies over a magnetic disk.
FIG. 3 is a detailed view of the magnetic disk device, and FIG. 4 shows a situation in which the usable data area of the magnetic disk is limited by atmospheric pressure in the magnetic disk device having a pressure sensor.

The magnetic disk device 10 comprises a magnetic head slider 12 and a magnetic disk 14. The pressure sensor 16 is attached to the circuit portion of the magnetic disk device 10. Since the pressure sensor 16 is installed under the magnetic disk 14, it is indicated by a dotted line.

The magnetic disk device 10 includes a magnetic disk 1
Spindle motor 18 for rotating 4, magnetic head slider 12 for recording and reproducing information on magnetic disk 14, and actuator unit 2 for moving magnetic head slider 12 in the radial direction of magnetic disk 10.
It has 0.

The magnetic head slider 12 is supported by a suspension 22. In addition, the actuator unit 20 includes a suspension 22 of the magnetic head slider 12.
And a voice coil motor 26 that gives a driving force to the carriage 24.

The magnetic signal read from the magnetic disk 14 by the magnetic head slider 12 is converted into an electric signal by the transducer 28 on the magnetic head slider 12 and processed by the signal processing unit 30. The voice coil motor 26 of the actuator unit 20 moves the magnetic head slider 12 to an arbitrary position in the radial direction of the magnetic disk 14 so as to move the actuator control unit 32.
Is controlled by.

A motor controller 34 is provided for keeping the number of rotations of the spindle motor 18 for rotating the magnetic disk 14 constant during recording and reproduction. The signal processing unit 30,
The actuator control unit 32 and the motor control unit 34 are
It is connected to a central control unit 36 for comprehensively controlling the entire apparatus.

FIG. 4 shows the magnetic disk 14 depending on the atmospheric pressure.
3 shows a specific example of limiting the available data area 38 of FIG. This example will be described by using a 2.5-inch magnetic disk device having a total capacity of 40 GB, in which two magnetic disks 14 are mounted.

The magnetic disk 14 is allocated with recording tracks of 33000 cylinders, and the outermost peripheral portion is 0 cy.
As l, the cylinder number is set to increase toward the inner peripheral side.

An area of 0 to 8 cyl at the outermost periphery is a management area 40, and here the magnetic disk device 1 is provided.
Management information of 0, specifically information such as model name and serial number, is recorded. The information recorded in the magnetic disk device 10 is written in the data area 38 after 9 cyl excluding the management area 40. In a normal flat environment, the entire data area 38 is used to read / write the recorded information.

FIG. 5 shows the flying distribution of the magnetic head slider 12. Magnetic head slider 12 and magnetic disk 10
The head flying height 42 increases as the relative speed to
Becomes higher. In the case of a magnetic head slider in the current flatland environment, the head flying height is 15 nm at the innermost side where it drops the most.
It is a degree.

When the atmospheric pressure decreases, the viscosity of the air flow 44 decreases, and the head flying height decreases. The amount of levitation reduction due to atmospheric pressure is 0.7 to 1.0 nm for an altitude of 1000 m.
Is. In addition, since there is almost no difference in the amount of levitation drop due to atmospheric pressure between the inner and outer circumferences, the levitation distribution in the highland environment is a distribution obtained by sliding the levitation distribution in the flatland environment in parallel, as shown in FIG. ing.

Generally, in the case of a 2.5-inch magnetic disk device,
Environmental specifications for altitude are 3000m. In comparison with a flatland environment, in an environment of an altitude of 3000 m, the head flying height is reduced by about 3 nm over the inner and outer circumferences on the magnetic disk surface. In consideration of variations in the product head flying height, it is expected that the head flying height will be 10 nm or less on the inner peripheral side where the flying height is the lowest.

In a flat environment, the magnetic head slider 1
The magnetic disk device 10 is shipped after confirming that the contact between the magnetic disk 14 and the magnetic disk 14 does not occur. Therefore, as a product, the flying height at the innermost position of the magnetic disk is the magnetic head slider 12 and the magnetic disk 14
Contact does not occur.

In order to avoid the contact state in the high altitude environment, the use area of the data area 38 may be limited so that the magnetic head slider 12 does not reach the innermost side of the magnetic disk.

In the present invention, the innermost circumferential side of 3000 cyl is set as the data restriction area 46. As shown in FIG. 5, this setting includes the flying height of the innermost circumferential position of the data area 38 in the flat environment and the data area 3 in the altitude of 3000 m.
This is based on the fact that the flying heights of the innermost peripheral positions of 8 are almost equal.

Next, the operation according to the present invention will be described. A pressure sensor 16 attached to the magnetic disk device 10 detects an altitude state in a use environment. In the present invention, when the environment corresponding to an altitude of 3000 m or higher, or the atmospheric pressure of 0.69 atm or less, the data area 4
It was set to give a switching instruction of 8.

In the range of level ground environment to altitude of 3000 m,
The writing / reading operation of the recorded information is performed in the entire area of the data area 38. When the environment is at an altitude of 3000 m or higher, the recording information is written / read in the data area (high altitude environment) 48 excluding the data restriction area 46.

Magnetic head slider 12 and magnetic disk 1
When 4 touches, the magnetic head slider 12 vibrates, and in many cases, particularly during writing operation, the vibration causes off-track. On the other hand, the read operation can be performed without any problem. In the present invention, regarding the operation of the data restricted area 46 in the highland environment, the write operation is prohibited and the read operation is enabled.

In the present invention, the central control unit 36 limits writing to the data area 38 of the magnetic disk 14 depending on the atmospheric pressure detected by the pressure sensor 16. The inner side of the magnetic disk 14 where the flying height of the magnetic head slider 12 becomes low is set as a data restricted area 46.

As described above, according to the present invention, by writing the magnetic head in the data area where the magnetic head slider and the magnetic disk are easily contacted by grasping the advanced use environment based on the detection information of the atmospheric pressure detecting section. By avoiding the operation, the reliability of the magnetic disk device can be improved.

In the present invention, as shown in FIG. 6, a mode changeover switch 50 may be mounted on the magnetic disk device 10. When the user's use environment is known to be a highland environment in advance, the mode changeover switch 50 is set to the highland side from the beginning to limit the area of the data area 38.

That is, when used in a highland environment,
The mode selector switch 50 is switched to the HIGH side, and when used in a normal environment, it is switched to the NORNMAL side. These switching can be performed manually.

Although the present invention mainly focuses on self-setting of the magnetic disk device itself, it can be applied even after the magnetic disk device 10 is mounted on a personal computer. The altitude setting program may be set on the personal computer side, and the environment mode of the magnetic disk device 10 may be switched from the host side.

[0038]

According to the present invention, by limiting the data area area of the magnetic disk based on the detection information of the atmospheric pressure detecting section, the magnetic field in the data area where the magnetic head slider and the magnetic disk are easily contacted with each other. The write operation of the head can be avoided, and the reliability of the magnetic disk device can be improved.

[Brief description of drawings]

1A and 1B are schematic views of the inside of a magnetic disk device.

FIG. 2 is a schematic diagram for explaining how a magnetic head flies over a magnetic disk.

FIG. 3 is a detailed view of a magnetic disk device.

FIG. 4 is a diagram illustrating area setting of a magnetic disk.

FIG. 5 is a diagram for explaining changes in the head flying height when the pressure changes.

FIG. 6 is a diagram showing a magnetic disk device with a mode changeover switch.

[Explanation of symbols]

10 ... Magnetic disk device, 16 ... Pressure sensor, 14 ... Magnetic disk, 38 ... Data area, 46 ... Data restricted area, 48 ... Data area (highland environment), 40 ... Management area, 12 ... Magnetic head slider, 42 ... Head Flying height, 50 ... Mode switch.

Claims (5)

[Claims] 1. A magnetic disk device comprising an atmospheric pressure detecting section for detecting atmospheric pressure, a magnetic disk for recording information, and a magnetic head slider movable on the magnetic disk, based on detection information of the atmospheric pressure detecting section. And a recordable data area area of the magnetic disk is limited. 2. The magnetic disk device according to claim 1,
5 to 20% of the innermost circumference of the data area of the magnetic disk
Is set as the data area limited area, and the information write operation is not performed in the data area limited area. 3. The magnetic disk device according to claim 1,
5 to 20% of the innermost circumference of the data area of the magnetic disk
Is set as the data area restricted area, and the information writing operation in the data area restricted area is not performed in a usage environment at an altitude of 3000 m or higher. 4. An atmospheric pressure detector for detecting atmospheric pressure, a disc for recording information, and a write / read head slider movable on the disc, wherein the disc has a first area and a second area. The information recording apparatus is characterized in that the first area is always writable with information, and the second area is restricted from being writable based on the detection information of the atmospheric pressure detection unit. 5. An atmospheric pressure detecting unit for detecting atmospheric pressure, a disk having a plurality of areas for recording information, and a write / read head slider movable on the disk, wherein the plurality of areas of the disk are An information recording apparatus, wherein writing of information can be selected based on the detection information of the atmospheric pressure detection unit.