JP3070274B2 - Servo track writing method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo track writing apparatus for writing servo information by forming servo tracks on a servo surface of a disk medium, and in particular, to eliminate the influence of wind pressure generated as the disk medium rotates. Thus, the present invention relates to a servo track writing method and apparatus capable of writing high-quality servo information.

2. Description of the Related Art A magnetic disk device reads servo information written on a servo track formed on a servo surface of a disk medium, positions a data head on a cylinder designated by a host device based on the servo information, and reads the data. Is being written or read.

In recent years, there has been a strong demand for increasing the capacity of a magnetic disk drive, and the track spacing has been reduced, so that high-quality servo information has been demanded. Vibrates when the actuator positioned at the servo track receives wind pressure accompanying the rotation of the disk medium.

[0004] When such vibrations occur, the quality of servo information is remarkably deteriorated. Therefore, it is necessary to prevent the actuator from being affected by wind pressure.

[0005]

2. Description of the Related Art Conventionally, a magnetic disk device, which is a product, is used, and the amount of movement of an actuator for carrying a servo head of the magnetic disk device is measured by a laser displacement meter to control the servo track following of the servo head. The method of writing servo information and the product uses only a disk medium and a spindle motor, uses a dedicated servo track writing device, measures the amount of movement of the actuator of this servo track writing device with a laser displacement meter, and There is a method in which servo information is written by controlling the servo track following of a head attached to the tip of the disk.

[0006]

As described above, the amount of movement of an actuator of a magnetic disk device, which is a conventional product, is detected by a laser displacement meter, and the servo head is controlled so as to follow a servo track, or a dedicated servo track is used. The amount of movement of the actuator of the servo track writing device is detected by a laser displacement meter, and the head is controlled so as to follow the servo track. However, all of these actuators are protected from wind pressure caused by rotation of the disk medium. Absent.

Accordingly, these actuators vibrate under the influence of wind pressure generated as the disk medium rotates. From the servo information written to the servo track by this vibration, since the head does not accurately follow the track indicated by the laser displacement meter, servo information that meanders from an ideal servo track can be obtained. However, there is a problem that the quality is deteriorated.

In view of the above problems, the present invention provides an arm cover that covers the arm portion of the actuator in a non-contact manner, and moves the arm cover in accordance with the movement of the actuator, so that the wind hitting the arm portion of the actuator can be prevented. The purpose is to prevent the actuator from vibrating.

[0009]

FIG. 1 is a diagram for explaining the principle of the present invention. The servo track writing device includes a cover 6 that covers the arm 3 of the actuator 2 in a non-contact manner with the actuator 2 so that the arm 3 of the actuator 2 does not receive the wind pressure generated by the rotation of the disk medium 5. Moving means 7 for moving the cover 6 according to the amount of movement of the arm 3 of the actuator 2, and by detecting the position of the actuator 2, the head 4 attached to the tip of the arm 3 of the actuator 2 Control is performed so as to follow a predetermined track of the disk medium 5, and servo information is written to the track.

At this time, the cover 6 is attached to the actuator 2
Arm 3 of the actuator 2 so as not to contact
The cover 6 is moved in the same direction as the moving direction. That is, when the arm 3 of the actuator 2 is rotated about the rotation axis, the cover 6 is moved linearly. When the arm 3 of the actuator 2 is rotated about the rotation axis, the cover 6 is also moved. When the arm 3 of the actuator 2 is moved linearly by rotating about the rotation axis, the cover 6 is also moved linearly.

[0011]

With the above construction, the actuator 6 does not vibrate because the cover 6 prevents the wind pressure generated by the rotation of the disk medium 5 from rotating the arm 3 of the actuator 2.

Therefore, the head 4 attached to the tip of the arm 3 can normally follow a predetermined track based on the position signal detected by the laser displacement meter 1. Therefore, high-quality servo information can be written on the servo surface of the disk medium 5.

[0013]

FIG. 2 is a block diagram of a circuit showing an embodiment of the present invention. When the disk assembly having the disk medium 5 mounted on the spindle motor 14 is set in the servo track writing device, the control circuit 8 loads the clock head 13 and the servo head 4 to predetermined positions on the disk medium 5, and 14 is driven to rotate the disk medium 5.

Next, when the control circuit 8 sends clock information to the clock head 13 and writes the clock information to the disk medium 5, the control circuit 8 reads this clock information and checks the rotation fluctuation of the disk medium 5.

If the fluctuation of the rotation of the disk medium 5 does not reach the predetermined value, the clock information is again sent to the clock head 13 for writing, and read again to check the rotation fluctuation of the disk medium 5.

If the clock information is normally written,
The control circuit 8 drives the VCM 12 from the position of the actuator 2 detected by the laser displacement meter 1 via a VCM (voice coil motor) drive circuit 9, and positions the servo head 4 attached to the tip of the arm 3 of the actuator 2. Then, the servo information is sent to the servo head 4 in synchronism with the clock information read by the clock head 13, and the servo information is written to all the tracks on the servo surface of the disk medium 5.

At this time, the control circuit 8 drives the stepping motor 11 via the stepping motor driving circuit 10 to move the cover 6 based on the position of the actuator 2 detected by the laser displacement meter 1 and to move the arm 3 of the actuator 2 And the cover 6 are moved so as not to contact with each other.

That is, there is a gap of about 1 to 5 mm in the seek direction between the tip of the arm 3 in the head 4 mounting direction and the cover 6, whereas the feed pitch of the arm 3 is several tens μm.
Very small with below.

When writing servo information, the position of the head 4 mounted on the arm 3 is detected by the laser displacement meter 1 as described above, and the actuator 2 is moved one track at a time. .

Therefore, by calculating the moving distance of the cover 6,
When the cover 6 is moved by the step motor 11, there is a sufficient margin for an error in the movement amount and a time delay, and the arm 3 does not come into contact with the cover 6.

When the writing of the servo information is completed, the control circuit 8 checks the accuracy of the servo information read by the servo head 4, and if not, writes the servo information again. When the servo information is normally written, the control circuit 8 stops the spindle motor 14.

The VCM 12 and the step motor 11
Is driven in the same manner as described above, and the actuator 2 and the cover 6 are driven.
Are simultaneously moved to unload the servo head 4 and the clock head 13 as well.

At this point, the disk assembly on which the servo information has been written is removed from the servo track writing device. 3 to 5 are diagrams for explaining a configuration example of the present invention.

FIG. 3 shows a case where the arm 3 of the actuator 2 rotates about the rotation shaft 15 and the cover 6 moves linearly. FIG. 4 shows a case where the arm 3 of the actuator 2 rotates about the rotation shaft 15. 5 shows a case where the arm 3 of the actuator 2 moves linearly and the cover 6 also moves linearly.

In FIG. 3, the clock head 13 is mounted on a surface plate 19 of a servo track writing device by a mounting table 20, and is not moved after being positioned at a predetermined position on the disk medium 5, so that it is fixedly loaded. Is done.

The VCM 12 comprises a movable coil 17 and a fixed coil 16 and is stored inside a magnetic circuit 21. The magnetic circuit 21 is mounted on a surface plate 19. The movable coil 17 is attached to the actuator 2.

The rotary shaft 15 of the actuator 2 is connected to the actuator support arm 2 attached to the magnetic circuit 21.
The head 4 attached to the end 2 of the arm 2 of the actuator 2 is held at a predetermined height from the surface plate 19.

The cover driving device 23 attached to the surface plate 19 comprises the step motor 11, a rack constituting a part of the cover 6, and a roller for holding the rack. Thus, it is formed so as to cover the arm 3 of the actuator 2.

As described above, the actuator 2 has the VC
The movable coil 17 of M12 is attached, and VCM1
The movable coil 17 is driven by the magnetic field formed by the driving current sent from the VCM driving circuit 9 shown in FIG. 2 to the moving coil 17 placed in the magnetic field formed by the two fixed coils 16. Accordingly, the servo head 4 attached to the tip of the arm 3 is moved in the direction of the arrow A or B in the direction of the arrow A or B around the rotation shaft 15.

At this time, a pulse current is supplied to the step motor 11 from the step motor drive circuit 10 shown in FIG. 2, and a gear attached to the rotating shaft of the step motor 11 To rotate together, the cover 6 is moved linearly in the direction of arrow C or D.

That is, when the arm 3 rotates in the direction of arrow A, the cover 6 moves in the direction of arrow C. Therefore, the arm 3 of the actuator 2 is prevented from being affected by the wind pressure due to the rotation of the disk medium 5 by the cover 6 and the arm 3 vibrates because the cover 6 does not contact the arm 3. And the servo head 4 can write high-quality servo information.

The disk assembly is a disk medium 5
The spindle motor 14 is attached to the surface plate 19 by the spindle support arm 24, and is removed from the surface plate 19 when servo information is written.

In FIG. 4, a gear 18 meshing with a gear of a step motor 11 is attached to the rotating shaft 15 so that the cover 6 rotates about the rotating shaft 15. Is installed.

As shown in FIG. 3, the actuator 2 rotates in the direction of the arrow A or B about the rotation shaft 15, so that the servo head 4 attached to the tip of the arm 3 is rotated.
Also moves in the direction of arrow A or B.

At this time, since the step motor 11 rotates as in FIG. 3, the cover 6 also rotates in the same direction as the rotation direction of the arm 3. Therefore, the arm 3 of the actuator 2
The cover 6 prevents the disk medium 5 from being affected by the wind pressure caused by the rotation of the disk medium 5, and the cover 6
Does not contact the arm 3, the arm 3 does not vibrate, and the servo head 4 can write high-quality servo information.

The method of mounting the actuator 2, the step motor 11, the clock head 13, and the disk assembly on the surface plate is the same as in FIG. In FIG. 5, the actuator 2 is a moving coil 17 of the VCM 12.
Is linearly driven in the direction of arrow C or D by the magnetic field of the fixed coil 16, so that the servo head 4 attached to the tip of the arm 3 also moves linearly in the direction of arrow C or D.

At this time, as described above, the step motor 11 is rotated by the pulse current supplied from the step motor drive circuit 10 in FIG. 2, and the gear attached to the rotation shaft of the step motor 11 is provided on the cover 6. The cover 6 is moved linearly in the direction of arrow C or D in order to rotate while meshing with the rack.

Therefore, the arm 3 of the actuator 2 is
The cover 6 prevents the disk medium 5 from being affected by wind pressure caused by rotation, and the cover 6 does not come into contact with the arm 3, so that the arm 3 does not vibrate and the servo head 4 has a high quality. Good servo information can be written.

The method of mounting the actuator 2, the step motor 11, the clock head 13, and the disk assembly on the surface plate is the same as in FIG. FIG. 6 is a flowchart illustrating the operation of FIG.

The servo track writing device includes a step
When the disc assembly is set in (1), step (2)
To load the clock head 13 and the servo head 4,
In step (3), the spindle motor 14 is rotated. Then, in step (4), a reference write for writing clock information to the disk medium 5 is executed.

In step (5), a reference read for checking the written clock information is performed. In step (6), it is checked whether the clock information is normal.
If the rotation fluctuation is not normal, the process returns to step (4). If normal, the format write is executed in step (7).

That is, the servo head 4 is positioned by the laser displacement meter 1, and the servo information is written to all the tracks on the servo surface of the disk medium 5 while adjusting the timing with the clock information. At this time, the cover 6 is also moved based on the position information of the actuator 2 sent from the laser displacement meter 1.

Then, in step (8), it is checked whether the verification is successful. That is, the accuracy of the written servo information is checked, and if it is not possible, the process returns to step (7). If the accuracy of the servo information is good, the rotation of the spindle motor 14 is stopped in step (9). After that, the unloading of the clock head 13 and the servo head 4 is executed in step (10). At this time, the cover 6 is also moved at the same time.

Then, in step (11), removal of the disk assembly is recognized.

[0045]

As described above, according to the present invention, it is possible to write high-quality servo information in order to prevent the arm of the actuator from vibrating under the influence of the wind pressure accompanying the rotation of the disk medium.

[Brief description of the drawings]

FIG. 1 illustrates the principle of the present invention.

FIG. 2 is a block diagram of a circuit showing one embodiment of the present invention.

FIG. 3 illustrates a configuration example of the present invention (part 1).

FIG. 4 illustrates a configuration example of the present invention (part 2).

FIG. 5 illustrates a configuration example of the present invention (part 3).

FIG. 6 is a flowchart for explaining the operation of FIG. 2;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laser displacement meter 2 actuator 3 arm 4 servo head 5 disk medium 6 cover 7 moving means 8 control circuit 9 VCM drive circuit 10 step motor drive circuit 11 step motor 12 VCM 13 clock head 14 spindle motor 15 rotation axis 16 fixed coil 17 movable Coil 18 Gear 19 Surface plate 20 Mounting table 21 Magnetic circuit 22 Actuator support arm 23 Cover drive 24 Spindle support arm

Claims (5)

(57) [Claims] An arm (3) of the actuator (2) is not in contact with the actuator (2) so as not to receive a wind pressure generated by rotation of the disk medium (5). A cover (6) for covering the arm (3);
Moving means (7) for moving the actuator (6) in accordance with the amount of movement of the arm (3) of the actuator (2), and by detecting the position of the actuator (2),
The head (4) attached to the tip of the arm (3) of (2)
In a servo track writer for controlling to follow a predetermined track of the disk medium (5) and writing servo information to the track, the cover (6) is prevented from contacting the actuator (2). A servo track writing method, wherein the cover (6) is moved in the same direction as the movement direction of the arm (3) of the actuator (2). 2. The servo track writing device according to claim 1, wherein when the arm (3) of the actuator (2) is rotated about a rotation axis, the cover (6) is moved linearly. 2. The servo track writing method according to claim 1, wherein: 3. The servo track writing device, wherein when the arm (3) of the actuator (2) is rotated about a rotation axis, the cover (6) is also rotated about the rotation axis. Claim 1 characterized by the following:
The servo track writing method described. 4. The servo track writing device according to claim 1, wherein, when the arm (3) of the actuator (2) is moved linearly, the cover (6) is also moved linearly. Item 7. The servo track writing method according to Item 1. 5. A head (4) attached to a tip of an arm (3) of the actuator (2) follows a predetermined track of a disk medium (5) by detecting a position of the actuator (2). A servo track writing device for writing servo information to the track, wherein the arm (3) of the actuator (2) controls the wind pressure generated with the rotation of the disk medium (5). So as not to receive
Non-contact with the actuator (2)
A cover (6) for covering the arm (3) of (2), and a moving means (7) for moving the cover (6) according to the amount of movement of the arm (3) of the actuator (2). The servo track writing is characterized in that the cover (6) is moved in the same direction as the movement direction of the arm (3) of the actuator (2) so that the cover (6) does not contact the actuator (2). apparatus.