JPH052729A - Magnetic disk device format method and magnetic disk - Google Patents

Abstract

(57) [Summary] [Purpose] Make the hard disk format work by the disk drive alone. [Structure] A multi-gap head is used as the recording / reproducing head 303, and pit rows 304 and 306 are formed in advance at the outermost peripheral portion of the disc at the time of manufacturing the disc to serve as reference tracks. Set this reference track to the gap on the outer peripheral side.
Servo is applied while playing at 301, and at the same time, new formatting is performed at the gap 302 located inside. The operation is sequentially repeated toward the inner circumference to format the entire surface of the disk. [Effect] The format writing device becomes unnecessary and the required time can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device formatting method and a magnetic disk for writing a format signal by itself.

[0002]

2. Description of the Related Art In a magnetic disk drive having a high track density, position information written on the disk surface is read by a magnetic head and servo is applied in a closed loop to accurately position the magnetic head with respect to a track. A method of radially writing information about a track servo on a recording surface in correspondence with a recording sector, and recording data in a fan-shaped area sandwiched in a portion where the information about this servo is recorded (hereinafter referred to as a servo section) ( Sector servos are often used, especially in small disk drives.

This servo information is recorded using a magnetic head in the disk device manufacturing process. For this purpose, for example, in the drive manufacturing process, while the drive device (actual device) equipped with this disk is placed on the pedestal, the arm equipped with the head is mechanically moved from the outside to finely correspond to the track. Move the position,
The necessary servo information is written on the disk surface according to the movement.

The servo information relating to this position must not only indicate the position in the radial direction of the disk, but also strictly control the position in the direction along the circumference. Otherwise, when the head moves across the track at high speed, the servo signal loses regularity and causes errors.

FIG. 2 shows an example of a conventional format writing method based on this principle. In the figure,
200 is a drive base, 211 is a disk, 201 is a clock recording / reproducing head, and is supported by an arm 210.
The drive head 204 is supported by an arm 208. A reflection mirror 207 is temporarily fixed on the center of rotation of the arm. 2
Reference numeral 05 is a laser light source, and 206 is a photodetector.

The procedure for writing a servo signal according to this configuration is as follows.

(1) The reference clock and the servo signal are written on the outermost circumference of the disk 211 by using the clock signal read / write head 201 while referring to the rotation signal obtained from the rotary encoder incorporated in the spindle motor.

(2) While weakly energizing the voice coil motor 202, by gently pushing the arm 208 with the probe 203,
The magnetic head 204 is positioned slightly inside the track written in (1).

(3) While using the reproduction signal from the clock signal reading / writing head 201 as a reference clock, the signal reading / writing head 204 writes the servo signal over one revolution.

(4) The light emitted from the laser light source 205 is reflected by the reflection mirror 20.
Enter 7 to enter the optical sensor 206. If the optical sensor is made of CCD or the like so that the position can be detected, the rotation angle of the reflection mirror, that is, the position of the head 204 can be electrically known. By pushing the probe while electrically feeding back this, the head 204 can be sequentially positioned toward the inner circumference at a constant pitch for formatting.

Currently, most drives write servo information in the same or similar manner in principle.

[0012]

In the case of the conventional example, in order to move the head arm from the outside, this work must be performed with the cover of the drive removed.
That is, the work is performed in a clean room.

Therefore, when mass production is attempted by this method, (1) Since one drive is mounted on the servo track writer and writing is performed for each track, it takes 10 minutes or more.

(2) A large number of complicated and expensive servo track writers must be prepared. Such a problem occurs.

This in turn increases the manufacturing cost of the drive.

[0016]

A head having two recording / reproducing gaps arranged at a predetermined interval in the radial direction of a disk is prepared. In the outermost peripheral portion of the disc, a pit row is embedded over the entire periphery of the disc in the disc manufacturing process.

Each gap is connected to another recording / reproducing circuit. Since the magnetic recording film is also dented on the pit and the distance to the magnetic gap is increased, an electric signal corresponding to the pit can be obtained in the recording / reproducing coil of the magnetic path having the gap.

The reference clock signal is also reproduced while tracking is performed based on the reference servo signal obtained from the pit train, which is reproduced by the gap on the outer peripheral side. At this time, a predetermined servo signal and a reference clock signal are written in the gap on the inner circumference side.

Then, the head is slightly moved to the inner circumference side, servo is applied while the format signal recorded above is reproduced by the head located on the outer circumference side, and a new format signal is written by the head located on the inner circumference side. Perform.

This operation is sequentially repeated in the inner peripheral direction to format the entire surface of the disk.

[0021]

1 is a perspective view of a head according to the present invention. In the figure, 101 is a slider, 102 and 103 are thin film heads, and 104 and 105 are respective magnetic gaps. Ten
6 is a suspension that supports the head.

FIGS. 3a and 3b are enlarged views of the disk and the head as viewed from above in order to show how the format information is sequentially written using the magnetic head shown in FIG. 301 is an outer peripheral side gap and 302 is an inner peripheral side gap. 304 and 306 are pits (hollows) previously formed on the disc.

Such depressions may be formed, for example, by forming the disk substrate with resin, and the protrusions of the mold may be transferred during injection molding. If a magnetic metal thin film is formed on such a substrate by plating or sputtering, since these films are very thin, a dent appears even on the disk surface as it is. If a magnetic metal thin film with such a depression is previously magnetized with direct current, the total amount of magnetic flux that links the gap changes with time when the gap passes, and a read output corresponding to the depression is obtained. To be

The procedure of format writing by this head will be described below.

(1) The magnetic head 301 located on the outer peripheral side passes through the pit rows 304 and 306. The pit string 304 is a clock signal for creating timing, and the pit string 306 is a wobble pit for applying tracking servo. Detecting and tracking a position error by using such wobble pits is normally used in a disk device.

(2) At this time, the gap 302 located on the inner peripheral side
Magnetically records the clock signal 308 and the wobble signal 307.

(3) Next, the head is moved to the inner circumference by an amount equivalent to about one track pitch, and the gap 301 is drawn by servo over the track written using the gap 302. Figure 3b illustrates this. While rotating the disc 3 times in this state, using the gap 302,
Clock signal 305 and wobble signal 307 for servo
Write.

Writing a "wobble" signal can be accomplished by moving the entire head by applying a predetermined amount of offset set to the position error signal obtained by the gap 401. Hereinafter, such an operation is sequentially repeated until the innermost circumference. Note that 305 is a portion for writing user data, and nothing is recorded at this point.

FIG. 4 is a simplified block diagram showing how the above thin film magnetic head is connected to a circuit. The recording / reproducing circuits are independently provided so that the two magnetic poles can simultaneously record and reproduce independently. The servo circuits may be independent or may be shared and switched.

FIG. 5 illustrates a method of dealing with a case where two gaps are separated by a track distance or more.

In this example, the two gaps are attached to the head 503 at a distance of 4 times the track pitch. Therefore, pits for 4 tracks are created in advance. That is, while the gap 501 reproduces the outermost pit rows 504-1 and 506-1, the gap 502 magnetically records the format. Then, head 1
Move to the inner side of the track, and pit row 504 with gap 501
-Record the format magnetically in the gap 502 while playing -2 to 506-2.

Then, after repeating the same operation twice,
While the format signals 508 and 507 are reproduced in the gap 501, the format is magnetically recorded in the gap 502. Hereinafter, the same thing is repeated.

As the means for realizing the multi-gap (or the multi-gap head), the one formed by the thin film process is the most suitable, but the one by the conventional type machining is also possible. Further, the magnetic recording means may be either perpendicular recording or longitudinal recording.

Further, it is usual that the reference track is first recorded on the outermost circumference and then moved to the inner circumference side, but it is also possible to start from the inner circumference side and proceed to the outer circumference side.

Since the work of forming pits and grooves in the resin substrate by injection molding is a technique that has been put to practical use in optical disks, there is no problem. Even when using a metal substrate, it is possible to form pits by means of photochemical etching or the like.

[0036]

As described above, according to the present invention, the information on the track position is embedded at the same time when the substrate is formed, so that a special writing device or process is unnecessary.

By writing servo signals with the write head on the basis of pit reproduction signals, all track signals can be written by the drive alone. Therefore, since the servo track writer is unnecessary and the work performed in the clean room can be largely omitted, the throughput can be improved, the assembly time can be shortened, and the manufacturing cost can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of an example of a thin film magnetic head according to the present invention.

FIG. 2 is a diagram showing an example of a conventional format writing method.

FIG. 3 is an enlarged view of the disk and the head as seen from above to show how the format information is sequentially written in the magnetic disk device according to the present invention.

FIG. 4 is a simplified block diagram showing how a magnetic head connects to a circuit.

FIG. 5 is a diagram schematically showing another embodiment of the present invention.

[Explanation of symbols]

101 slider 104 Gap 105 gap 101 slider 301 Outer side gap 302 inner gap 304 pit row 306 pit row 303 head 307 format signal 308 format signal 501 outer circumference gap 502 inner gap 503 head 504-1 format signal 506-1 format signal

Claims (2)

[Claims] 1. A magnetic head having two recording / reproducing gaps arranged at a predetermined distance in the radial direction of the disc is used, and a pit which is regularly repeated on the disc substrate is provided at the outermost periphery of the disc. A method of formatting a magnetic disk device, which comprises forming a column and writing a format signal on the entire surface of the disk by the following procedure. (A) Tracking servo is applied while reproducing the pit row in the gap located on the outer circumference side, and at the same time, a new format signal is written in the gap located on the inner circumference side. (B) Move the head slightly inward,
The servo is applied while reproducing the format signal recorded by means of the head located on the outer circumference side, and the head located on the inner circumference side newly writes the format signal. (C) The above operation (b) is sequentially repeated in the inner circumferential direction to format the entire surface of the disc. 2. A magnetic head having two recording / reproducing gaps arranged at a predetermined distance in the radial direction of the disc is used, and a pit which is regularly repeated on the disc substrate is provided at the outermost periphery of the disc. A magnetic disk which is used to write a format signal on the entire surface of the disk by forming a row and forming a row of pits which are regularly repeated on the outermost circumference of the disk substrate. (A) Tracking servo is applied while reproducing the pit row in the gap located on the outer circumference side, and at the same time, a new format signal is written in the gap located on the inner circumference side. (B) Move the head slightly inward,
The servo is applied while reproducing the format signal recorded by means of the head located on the outer circumference side, and the head located on the inner circumference side newly writes the format signal. (C) The above operation (b) is sequentially repeated in the inner circumferential direction to format the entire surface of the disc.