JPH11260007A - Servo writing method and servo track writer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent recording of a servo signal from starting with a improper attitude of a flexible magnetic disk held by a spindle so as to prevent damage due to interference of a servo writer magnetic head and a magnetic disk or shell by detecting the attitude of the flexible magnetic disk prior to the recording of the servo signal. SOLUTION: A floppy disk F is set, and control means 17 causes a spindle 11b to rotate at a low speed. At this time, a magnetic head 18 for servo writing is retreated from the disk F. During this low-speed rotation, an optical sensor 14 measures the height of a surface of a hub 7 at constant time intervals so as to provide an attitude detecting means 16 with the measured data to determine the attitude of the hub 7. When the measured data varies during one rotation of the spindle 11b, the attitude detecting means 16 determines that the hub 7 is tilted, i.e., has an improper attitude. Furthermore, when the measured data has a constant value which exceeds an acceptable range, the hub 7 is determined to have an improper attitude in which the hub 7 is entirely floating above a receiving surface of the spindle 11b. The detection of the improper attitude is reported.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo write method and a servo track writer for recording a servo signal for accurately positioning a magnetic head of a floppy disk drive on a flexible magnetic disk medium.

[0002]

2. Description of the Related Art Heretofore, there has been provided a flexible magnetic disk medium in which magnetic layers are formed on both sides of a disk-shaped base made of a flexible polyester sheet or the like and signals can be magnetically recorded on the magnetic layers using a magnetic head. ing.

[0003] This flexible magnetic disk medium is usually provided as a floppy disk in which a hard center core (hereinafter also referred to as a hub) is mounted at the center of a disk and substantially the entirety is housed in a shell of plastic or the like. Because of their advantages such as easy handling and low cost, they are mainly used as recording media for computers. Zip, Hi among such floppy disks
In high-density floppies such as FD (high-density area of 200 TPI or more), it is necessary to position the magnetic head by closed loop control. For this control, concentric servo signals are recorded in advance on a flexible magnetic disk medium. Is required.

Here, as a method of recording a servo signal on a flexible magnetic disk medium, a method of recording a servo signal on a flexible magnetic disk medium alone before being housed in a shell or a state of attaching a hub to the center of the disk medium, There is a method in which disk media with a hub is housed in a shell.However, since careful handling is not required, it is easy to handle.From the viewpoint of reducing dropout, the latter, that is, a servo write in the shell, is used. Is preferably performed.

FIG. 2 shows an example of a servo track writer for recording this servo signal.

[0006] The illustrated servo track writer 10 uses a hub 11, which is fixed to the center of a magnetic disk medium 6 of a floppy disk F, to apply a magnetic force to a hub 11 provided by a hub chuck 12 provided above the spindle 11.
The magnetic disk medium 6 rotates with the rotation of the spindle 11, and the servo write magnetic heads 18, which are installed vertically facing each other so as to sandwich the floppy disk F, rotate during this rotation. The servo signal is recorded on the disk medium 6.

The servo write magnetic head 18 is mounted on a linear guide 20 provided on a guide 19a on a base 19 so as to reciprocate toward the center of the spindle 11, and is loaded at a predetermined position by a load mechanism (not shown). You. Further, a laser length measuring device 25 for detecting the position of the servo write magnetic head 18 is provided. A reflector 21 is installed on the linear guide 20, and a laser beam is emitted from the laser transducer 26 of the laser length measuring device 25 to the reflector 21 via the half mirror 27, and the reflected light is incident on the receiver 28 via the half mirror 27. The position is detected based on the length measurement. Then, the servo write magnetic head 18 is positioned and the actuator is driven in accordance with the length measurement.

A clock signal hard disk 13 is installed on the spindle 11 coaxially with the floppy disk F, and a clock signal is recorded and reproduced on the hard disk 13 by a reference clock head 15. As the clock signal hard disk 13 and the reference clock head 15, those of a known hard disk device can be applied.

Note that a two-dot chain line in the figure indicates a shell for accommodating the magnetic disk medium 6 on which the hub 7 is mounted.

[0010]

When a servo signal is recorded on a magnetic disk medium by the servo track writer, the hub fixed to the center of the magnetic disk medium is accurately positioned at a proper holding position with respect to the spindle. May not be chucked.

For example, in the method of positioning the magnetic disk medium by the center pin of the spindle and the center hole of the hub, as shown in FIG. 3A, the flange of the center hole is hooked on the center pin and the hub is inclined with respect to the spindle. In some cases, or the whole hub may stop in a state of floating from the hub receiving surface of the spindle as shown in FIG.
Attempting to write servo signals with these chucking abnormalities may cause the magnetic head of the servo writer to interfere with the magnetic disk media or shell, causing damage to either, and also cause a 3.5-inch 2MB. A combination of a directional hub such as a floppy disk and a hub chuck (a hub receiving surface and a magnet for suction) may damage the drive pin.

Further, there is another problem that the contact of the magnetic head with the front and back surfaces of the magnetic disk medium becomes uneven, and it is impossible to record a servo signal with high quality.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a servo write method and a servo track writer that record a high-quality servo signal while holding a flexible magnetic disk in a proper posture. It is the purpose.

[0014]

SUMMARY OF THE INVENTION A servo write method and a servo track writer according to the present invention detect the attitude of a held flexible magnetic disk medium prior to recording of a servo signal.

That is, the servo write method of the present invention
The center core (hub) fixed to the center of the flexible magnetic disk medium is held on the spindle, and this spindle is rotated to rotate the flexible magnetic disk medium together with the spindle. During the rotation period, servo signals are sent to the flexible magnetic disk medium. In the servo write method for recording, if the flexible magnetic disk medium is not housed in the shell prior to the recording of the servo signal, the posture of the center core or the posture of the flexible magnetic disk medium in the state of being held on the spindle, or the flexible magnetic disk medium When the disk medium is stored in the shell, the posture of the center core, the posture of the flexible magnetic disk medium itself, or the posture of the shell in the state of being held on the spindle is detected. It is characterized in.

Here, "prior to recording the servo signal"
This means that during the period before the servo signal is recorded, it may be before or after rotation of the magnetic disk medium. Therefore, the detection of the attitude of the magnetic disk medium or the like may be performed before or after the rotation of the magnetic disk medium as long as the servo signal is not recorded.

When the posture is detected after the rotation, the rotation period is divided into at least two stages having different rotation speeds.
During the period in which the rotational speed is relatively low among these two stages, the posture is detected, and based on the detection result of the normal posture, the period shifts to the period relatively higher than the low period, It is preferable to record the servo signal during the high-speed period in order to secure the posture detection accuracy and the servo write processing speed.

On the other hand, when the detection is performed before the rotation, the rotation of the flexible magnetic disk medium may be started based on the detection result of the normal posture.

As a result of this posture detection, the normal posture, that is, the magnetic disk medium or the like does not interfere with the magnetic head or the like of the servo writer at the time of recording the servo signal, and is correctly positioned at the regular holding position which does not cause the damage. When it is detected that the posture is in the arranged state, the servo signal may be recorded thereafter, and when it is detected that the posture is abnormal, an algorithm that performs the holding operation again may be used. An algorithm for notifying the operator or the like of the abnormal posture may be used.

As a method of detecting the posture, an optical detection method, an electrical detection method, a mechanical detection method, or the like can be employed. Specifically, the posture can be detected by measuring the absolute height of the hub (center core), the pressure distribution on the hub receiving surface, the gap between the hub receiving surface and the hub, and the like.

Note that the method of detecting the attitude by measuring the pressure distribution on the hub receiving surface can be performed before the rotation of the disk medium, while the other detection methods reduce the number of detection points and rotate the disk medium. Alternatively, measurement may be performed many times, or detection may be performed before rotation by providing a large number of detection points (at least three points in order to uniquely define a plane).

According to the servo track writer of the present invention, a center core fixed to the center of a flexible magnetic disk medium is held on a spindle by holding means.
In a servo track writer for rotating the spindle to rotate the flexible magnetic disk medium together with the spindle and recording a servo signal on the flexible magnetic disk medium by a servo signal recording means during the rotation period, the flexible magnetic disk medium has a shell. When stored in the spindle, the attitude of the center core or the attitude of the flexible magnetic disk medium itself held in the spindle,
Alternatively, when the flexible magnetic disk medium is housed in a shell, an attitude detecting means for detecting the attitude of the center core, the attitude of the flexible magnetic disk medium itself, or the attitude of the shell in a state of being held by a spindle is provided. It is characterized by comprising.

Here, the detection of the attitude of the magnetic disk medium or the like by the attitude detecting means may be performed before or after the rotation of the magnetic disk medium, as long as the servo signal is not recorded. When the detection is performed after the rotation, the rotation speed of the spindle is made variable in at least two different stages, and the posture detecting means detects the posture during the relatively low period of the two stages. And the spindle shifts to a period relatively higher than the low-speed period based on the detection result of the normal posture by the posture detection unit, and the servo signal recording unit during the high-speed period. The apparatus further includes control means for controlling the attitude detection means, the spindle and the servo signal recording means, so that the servo signal is recorded.
This is preferable for securing the attitude detection accuracy and the servo write processing speed.

On the other hand, when the detection is performed before the rotation, the spindle starts the rotation based on the result of the detection of the normal posture by the posture detecting means, and after the rotation, the servo signal recording means starts the rotation. What is necessary is just to further include control means for controlling the attitude detecting means, the spindle and the servo signal recording means so as to record the servo signal.

The result of the posture detection by the posture detecting means is that the posture is normal, that is, the magnetic disk medium or the like does not interfere with the magnetic head of the servo writer or the like when recording the servo signal. If the posture is correctly positioned in the position,
After that, the servo signal is recorded, and when it is detected that the posture is abnormal, the holding operation may be performed again or the operator may be notified of the abnormal posture. Good.

As the attitude detecting means, optical detecting means,
Electric detection means or mechanical detection means can be employed. Specifically, a method for detecting the attitude by measuring the absolute height of the hub (center core), the pressure distribution on the hub receiving surface, the gap between the hub receiving surface and the hub, or the like can be applied. .

In the method of measuring the pressure distribution on the hub receiving surface, the detection can be performed before the rotation of the disk medium. In the other method, the number of measurement is measured many times while rotating the disk medium with the number of detection points reduced. Alternatively, it is also possible to detect before rotation by providing a large number of detection points (at least three points to uniquely define a plane).

[0028]

The servo write method and the servo track writer of the present invention detect the attitude of a flexible magnetic disk medium held on a spindle or the like for recording a servo signal before recording the servo signal. It is possible to prevent the recording operation of the servo signal from being started while the posture of the disk medium is abnormal, thereby causing the magnetic head of the servo writer, the magnetic disk medium or the shell to interfere with any one of these. Can be prevented from being damaged.

Furthermore, since the magnetic head is evenly applied to the front and back surfaces of the magnetic disk medium, the quality of the recorded servo signal can be improved.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a servo writer which is an example of a servo track writer for performing the servo write method of the present invention.

The illustrated servo writer 10 has a spindle 11b which is rotationally driven by control means 17 which will be described in detail later.
At the upper end surface of the spindle 11b, it protrudes into a center hole of a hub (center core) 7 fixed to the center of a flexible magnetic disk medium 6 accommodated in a shell (shown by a two-dot chain line) of the floppy disk F. A center pin is provided, and this upper end surface is formed as a receiving surface of the hub 7. The receiving surface has a diameter smaller than that of the hub 7, and a step is formed outside the receiving surface, and a hub chuck 12 for chucking by a magnetic attraction force or the like is provided.

It is preferable to use an air spindle for the spindle 11b in order to reduce runout. With the rotation of the spindle 11b, the floppy disk F chucked on the hub chuck 12 is maintained at a predetermined rotation.

The rotation speed of the spindle 11b can be made variable, and can be switched between a low speed and a high speed by a control signal of the control means 17.

Outside the hub chuck 12, two optical sensors 14 fixed to a surface plate 40, which will be described later, are provided, each of which measures the height from its installation position to the hub 7 by a distance. , And based on a plurality of measurement data measured while the hub 12 is rotating, the posture detecting means 16
Calculates the holding posture of the hub 7 (the inclination and height of the spindle 11b with respect to the hub receiving surface).

The spindle 11b has a floppy disk F
A clock signal hard disk 13 is installed coaxially with
A clock signal is recorded and reproduced on the hard disk 13 by the reference clock head 15. A known hard disk device can be applied to the clock signal hard disk 13 and the reference clock head 15.

Spindle 11b, reference clock head 15
Is mounted on a surface plate 40, on which a magnetic head 18 for servo write is further disposed so as to face up and down so as to sandwich the floppy disk F. The magnetic head 18 for servo write is mounted on a guide 19 a on a base 19 by a spindle 11.
The linear guide 20 is attached to a linear guide 20 that is reciprocally movable toward the center of b, and is loaded at a predetermined position by a loading mechanism (not shown).

As the loading mechanism, a known technique such as ramp loading is adopted.

Further, a laser length measuring device 25 for detecting the position of the servo write magnetic head 18 is provided. A reflector 21 is installed on the linear guide 20, and a half mirror 27 is provided from a laser transducer 26 of a laser length measuring device 25.
The reflector 21 is irradiated with a laser beam via the optical disc, and the reflected light is incident on the receiver 28 via the half mirror 27, and the position is detected by measuring the length. The positioning of the servo write magnetic head 18 and the driving of the actuator are performed according to the length measurement.

In the servo write magnetic head 18, a slider 32 having a head core having a plurality of head gaps is fixed to the tip of a suspension 31.

The control means 17 controls the attitude detection means 16, the spindle 11b and the magnetic head 18 for servo writing.
The control means 17 controls the rotation speed of the spindle 11b, and causes the attitude detection means 16 to detect the holding attitude of the hub 7 during the low-speed rotation. Based on the detection result that the head is in the normal posture, the rotation speed of the spindle 11b is switched to the high speed side, and a servo signal is recorded by the servo write magnetic head 18 during the high speed rotation period.
Control these.

During the period before the spindle 11b rotates and during the low-speed rotation, the servo write magnetic head 18 is moved by the unload mechanism to the floppy disk F.
And is guided to a position where recording is performed on the magnetic disk medium 6 during the high-speed rotation of the spindle 11b.

Here, the result of the detection of the posture by the posture detecting means 16 is "normal posture" when the magnetic disk medium 6 or the shell (shown by a two-dot chain line) is recorded when the servo signal is recorded.
Does not interfere with the magnetic head 18 for servo writing, and the posture in a state where the hub 7 is disposed in a regular holding position (a state in which the hub 7 is evenly placed on the entire receiving surface of the spindle 11b) so as not to cause the damage. means.

On the other hand, if the posture detection result by the posture detecting means 16 is an abnormal posture, the notifying means (not shown) indicates that the posture of the hub 7 is not in the normal posture. It notifies the operator or the like that the recording of the servo signal by the head 18 is not performed. In response to this notification, the operator may correct the attitude of the floppy disk F. Of course, instead of applying such a notifying means, if the posture detection result by the posture detecting means 16 is an abnormal posture, the floppy disk F may be automatically reset. Good.

Here, "in an abnormal posture" means a posture that does not correspond to the normal posture.

The optical sensor 14 has a function of measuring the height of the hub 7. Instead, a light projector and a light receiver for receiving light from the light projector are installed in the horizontal direction. A gap between the receiving surface of the spindle 7 and the receiving surface of the spindle 11 may be detected, or a surface shake due to light shielding may be detected.

Further, instead of such an optical sensor,
An electric sensor, a mechanical sensor, or the like may be applied.

Next, the operation of the servo writer will be described.

First, the floppy disk F is set on the servo writer 10. This setting is for hub 7
Center hole of the spindle 11b protrudes into the center pin of the spindle 11b, and the hub 7 is arranged so as to contact the receiving surface of the spindle 11b.

Here, the setting may become abnormal. That is, the hub 7 rides on the center pin, and the whole floppy disk is inclined.

Next, under the control of the spindle 11b by the control means 17, the spindle 11b is rotated at a constant low speed. Then, the hub 7 and the magnetic disk medium 6 of the floppy disk F chucked to the spindle 11b rotate together with the spindle 11b. At this time, the servo write magnetic head 18 is
Have been evacuated.

Next, during this low-speed rotation period, the optical sensor
The height of the surface of the hub 7 on which the rotating member 14 rotates is measured at regular time intervals, and the measured data is input to the posture detecting means 16. The attitude detecting means 16 determines the attitude of the hub 7 based on the obtained data.

Here, for example, when the hub 7 rides on the center pin and the whole of the floppy disk is inclined, the measurement data of the optical sensor 14 does not show a constant value and one cycle of rotation of the spindle 11b takes one cycle. It fluctuates in proportion. The attitude detecting means 16 can determine from this fluctuating data that the attitude of the hub 7 is inclined. Even if the data shows a constant value, if the value is larger than the allowable range, the entire hub 7 is
It is determined that it is in a state of being raised from the receiving surface of 11b by a certain height (an aspect of an abnormal state).

As described above, the attitude detecting means 16 obtains the attitude of the hub 7 and inputs the detection result indicating whether the hub 7 is in the normal attitude or the abnormal attitude to the control means 17.

The control means 17 receives the result of the detection by the attitude detecting means 16, and when the result of the detection is "unusual attitude", the notifying means (not shown) informs the operator that the holding attitude of the floppy desk F is not normal. If the detection result is "normal posture", the notifying means (not shown) notifies the operator that the holding posture of the floppy disk F is not normal, and the rotation of the spindle 11b is increased. Further, the loading mechanism controls the servo write magnetic head 18 to approach the floppy disk F from the retracted state, and records a servo signal on the magnetic disk medium 6.

When the recording of the servo signal is completed, the magnetic head 18 is returned to the retracted state again, the rotation of the spindle 11b is stopped, and the recording of the servo signal is completed.

As described above, according to the servo writer 10 of the present embodiment, prior to the recording of the servo signal, the attitude of the hub 7 of the floppy disk F held on the spindle 11b for recording the servo signal is detected. As a result, it is possible to prevent the recording operation of the servo signal from starting while the attitude of the floppy disk F is in an abnormal state, whereby the magnetic head 18 interferes with the magnetic disk medium 6 or the shell, and Either one can be prevented from being damaged.

Further, since the magnetic head 18 can secure a uniform gap on the front and back of the magnetic disk medium 6, the quality of the recorded servo signal can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a servo writer which is an embodiment of a servo track writer of the present invention.

FIG. 2 shows a conventional servo track writer.

FIG. 3 is a diagram showing a problem in a conventional servo track writer.

[Explanation of symbols]

 6 Flexible magnetic disk media 7 Hub (center core) 10 Servo writer 11b Spindle 12 Hub chuck 13 Hard disk for clock signal 14 Optical sensor 15 Head for reference clock 16 Attitude detecting means 17 Control means 18 Magnetic head for servo write 20 Linear guide 25 Laser measurement Long container 31 Suspension 32 Slider 40 Surface plate F Floppy disk

Claims (6)

[Claims] 1. A center core fixed to a center portion of a flexible magnetic disk medium is held by a spindle, and the spindle is rotated to rotate the flexible magnetic disk medium together with the spindle. In a servo write method of recording a servo signal on a disk medium, prior to recording the servo signal, the attitude of the center core or the attitude of the flexible magnetic disk medium in a holding state on the spindle, or the flexible magnetic disk medium is a shell. A servo write method for detecting the attitude of the center core, the attitude of the flexible magnetic disk medium, or the attitude of the shell when the information is stored in the medium. 2. The method according to claim 1, wherein the posture of the flexible magnetic disk medium is detected before the rotation of the flexible magnetic disk medium, and the rotation of the flexible magnetic disk medium is started based on a detection result of a normal posture. The servo write method described. 3. The rotation period is divided into at least two stages having different rotation speeds, and the posture is detected during a period in which the rotation speed is relatively low among the two stages. 2. The servo writing method according to claim 1, wherein a transition is made to a period relatively higher than the low-speed period, and the servo signal is recorded during the high-speed period, according to the detection result of the presence. 4. A center core fixed to the center of the flexible magnetic disk medium is held by a spindle by holding means, and the spindle is rotated to rotate the flexible magnetic disk medium together with the spindle. In a servo track writer for recording a servo signal on the flexible magnetic disk medium by servo signal recording means, the attitude of the center core or the attitude of the flexible magnetic disk medium in the held state, or the flexible magnetic disk medium is a shell. And a posture detecting means for detecting the posture of the center core, the posture of the flexible magnetic disk medium, or the posture of the shell. Kkuraita. 5. The posture detecting means detects the posture before rotation of the flexible magnetic disk medium,
The attitude detection means, based on the detection result of the normal attitude by the attitude detection means, the spindle starts the rotation, and after the rotation, the servo signal recording means performs the recording of the servo signal, 5. The servo track writer according to claim 4, further comprising control means for controlling said spindle and said servo signal recording means. 6. The method according to claim 6, wherein the rotation speed of the spindle is variable in at least two different stages, and the posture detecting means detects the posture during a relatively low period of the two stages. The spindle shifts to a period relatively higher than the low-speed period based on the detection result of the normal posture by the posture detection unit, and the servo signal recording unit performs during the high-speed period. 5. The servo track writer according to claim 4, further comprising control means for controlling said attitude detecting means, said spindle and said servo signal recording means so as to record said servo signal.