JPH03283150A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To utilize the inner peripheral side of a magnetic disk effectively and to increase the capacity by setting the floating attitude of a slider freely. CONSTITUTION:Such a characteristic that the quantity of flotation of the slider 5 becomes larger at the outer periphery as the peripheral speed becomes faster is utilized. Then the yaw angle is set to, for example, 0 deg. on the basis of the innermost periphery of a data area and then the quantity of flotation on the inner peripheral side is set to a maximum value. Then the sufficient quantities of flotation with which no head crush occurs are obtained on the inner and outer peripheral sides. Consequently, the data area can be expanded to the inner peripheral side and an increase in the deviation in rotational track between the write head 10 and magnetic head 3 of a servo writer which accompanies the expansion is absorbed by an azimuth 22, so the capacity of a magnetic disk device can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a magnetic disk device, and particularly relates to writing and reading of servo data.

(Prior art) High-precision positioning is required for the magnetic head in a magnetic disk drive, but one side of a plurality of magnetic disks is used as a dedicated servo surface, and a position reference signal for positioning is written on this dedicated servo surface. Many of them employ a servo surface servo method in which the position reference signal is read out to control the positioning of the magnetic head. Additionally, there is a demand for lighter weight swing arms due to faster access times.

Here, a general magnetic disk device will be explained with reference to FIG.

A plurality of magnetic disks 1 are held by a rotating part of a spindle motor 2, and are rotationally driven in the direction of arrow A by a drive control part (not shown). A pair of magnetic heads 3 disposed facing each other on both sides of the magnetic disk 1 perform magnetic recording and reading on a recording layer formed on the surface of the magnetic disk 1. One surface of the plurality of magnetic disks l is a dedicated servo surface, on which a position reference signal for positioning is written by a servo writer of a separate device during the manufacturing process. This position reference signal is read by the magnetic head 3 facing the dedicated servo surface during operation of the magnetic disk device, and is used to write data.
The positioning of the reading magnetic head 3 is controlled based on the read position reference signal.

The magnetic head 3 is composed of a flexure 4 made of a leaf spring and a slider 5 fixed to one end of the flexure 4 and equipped with an electromagnetic transducer facing the magnetic disk 1, and fixed to a carriage 6 at the other end of the flexure 4. has been done. The carriage 6 is pivotally supported by a shaft 7, and V CM (Voice
Co11 Motor) 8 is rotatably driven in the direction of arrow B about the shaft 7 as a fulcrum.

Therefore, the magnetic head 3 is also rotatable in the direction of arrow B between the position shown by the solid line and the position shown by the dotted line in the figure along the surface of the magnetic disk l.

When the magnetic disk device operates, that is, when performing magnetic recording and reading, the magnetic disk 1 held by the rotating part of the spindle motor 2 rotates in the direction of arrow A.
The slider 5 floats as the magnetic disk l rotates.

When the rotation speed reaches a steady rotation speed, the carriage 8 becomes rotatable, and the VCM 8 positions the magnetic head 3 fixed to the carriage 6 to perform magnetic recording/reading in the data area 9 formed on the magnetic disk 1. Positioning control is performed based on position reference signals recorded on a dedicated servo surface.

By the way, FIG. 4 shows a simplified model of the relationship between the write head of a conventional servo writer and the magnetic head 3 of a magnetic disk device.As shown in FIG. is magnetic head 3
The slider 12 of the write head 10 of the servo writer and the slider 5 of the magnetic head 3 are also set to coincide with the axis 7 which is the rotation center of the servo writer. Therefore, the locus of rotation of the write head 1o of the servo writer from the innermost circumference to the outermost circumference of the data area 9 matches the rotation locus of the magnetic head 3, and the write head IO of the servo writer rotates on the magnetic disk 1. A position reference signal 13 is written in the rotation locus, and this position reference signal 13
is read by the magnetic head 3 facing the dedicated servo surface.

Further, when a rotating carriage is used, the slider 5 makes a certain angle (yaw angle) with the rotation tangent direction of the magnetic disk 1, but the yaw angle is set to 0° with the center 9a of the data area 9 as a reference. The circumferential side and outer circumferential side have positive and negative angles, respectively. Figure 5 shows the relationship between this yaw angle and the flying height of the slider 5.
As shown in the figure, the flying height is maximum at the center 9a of the data area 9 where the yaw angle is 01, and the flying height decreases toward the inner or outer circumference.

(Problem to be Solved by the Invention) As described above, the rotation center of the write head 10 of the servo writer is in the same position as the rotation center of the magnetic head 3 of the magnetic disk, and the rotation loci of each head are in the same position. Therefore, the position reference signal can be read by the magnetic head 3.

However, as disk devices become more compact and the rotation radius of the magnetic head 3 becomes smaller, the yaw angle is set to 00 at the center 9a of the data area 9. As the yaw angle increases, the flying height of the slider 5 decreases on the inner circumferential side, and there is a risk of a head crash, resulting in the problem that the inner circumferential side cannot be used effectively.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a magnetic disk device that can increase the capacity even if the disk device is downsized.

[Structure of the Invention] (Means and Effects for Solving the Problems) In order to achieve the above object, the present invention provides a magnetic head equipped with a slider that is rotatably driven by a rotary carriage and floats as a magnetic disk rotates. A magnetic disk device that controls the position of a magnetic head by reading servo data recorded on the servo surface of the magnetic disk, the servo writer having a rotation radius larger than the rotation radius of the magnetic head. a magnetic disk on which data is recorded; a means for reading the servo data with the magnetic head having a slider set with reference to a yaw angle at the innermost circumference of the data area of the magnetic disk; Since the structure is equipped with a position control means for controlling the position of the magnetic head based on the magnetic head, the flying posture of the slider can be freely set, so that the inner circumferential side of the magnetic disk can be effectively utilized. Large capacity can be achieved.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. Note that the same parts as in FIGS. 3 and 4 are given the same reference numerals, and detailed explanation thereof will be omitted.

FIG. 1 is a diagram showing the relationship between a write head of a servo writer and a magnetic head of a magnetic disk device according to an embodiment of the present invention, and FIG. 2 is a diagram showing the relationship between a slider and a flying height according to an embodiment of the present invention. It is a figure showing a relationship.

As shown in Figure 1, the writing head 1 of the servo writer
0 rotation center 20 is the axis 7 which is the rotation center of the magnetic head 3.
The write head 10 of the servo writer has a rotation radius larger than that of the magnetic head 3, and is set at a position farther from the magnetic disk 1 than the rotation axis 7 of the magnetic head 3. Therefore, the rotation locus of the write head 10 of the servo writer is closer to a straight line than the rotation locus of the magnetic head 3, and does not match the rotation locus of the magnetic head 3.

Further, a position reference signal 21, which is servo data, is recorded on the rotation locus of the write head 10 of the servo writer, and is read by the magnetic head 3. The discrepancy in the rotation locus is caused by providing the azimuth 22 on the write head IO of the servo writer and the magnetic head 3, and because the peripheral speed becomes faster on the outer circumferential side, the recording width becomes larger, so that the recorded data falls within the reading range of the magnetic head 8. By setting this, erroneous reading by the magnetic head 3 is prevented.

Furthermore, the flying height of the slider 5 is determined by utilizing the characteristic that the peripheral speed increases and the outer circumference increases as shown in FIG. By setting the yaw angle to, for example, 0° with the innermost circumference of the data area 9 as a reference, as shown in Figure 2 (B), the flying height on the inner circumference side will be maximized. is set to FIG. 2(C) shows a composite of these flying heights, and a sufficient flying height is obtained on the inner and outer circumferential sides so that no head crash occurs. Therefore, the data area 9 can be expanded to the inner circumferential side, and the increase in the deviation in the rotation loci of the servo data writing head 10 and the magnetic head 3 due to the expansion is absorbed by the azimuth 22, so that the size of the magnetic disk device can be reduced. Capacity can be increased.

Next, the operation of the present invention having the above configuration will be explained.

First, in the manufacturing stage of a magnetic disk device, a position reference signal 21, which is servo data, is recorded by a write head 12 of a servo writer having a long rotation radius.

Subsequently, during the operation of the magnetic disk device, that is, when writing and reading data, the slider 5 floats and the position reference signal 21 is read out by the magnetic head 3, which has a short rotation radius and a different rotation locus. Azimuth 22
Since the recording width is large at the outer periphery where the deviation becomes large and is set within the reading range of the magnetic head 3, misreading does not occur.

Then, the position of the magnetic head 3 to a desired track is controlled based on the read position reference signal 21.

In this way, even if the data area 9 is expanded to the inner circumferential side, stable writing and reading of servo data is performed, so that writing and reading of data is also stable.

In the above embodiment, the yaw angle at the innermost circumference is set to 09, but the yaw angle is not limited to this, and may be set to an appropriate angle depending on the specifications of the magnetic disk device.

Furthermore, it goes without saying that the present invention is not limited to the above embodiments, and can be modified in various ways without departing from the gist of the present invention.

[Effects of the Invention] As detailed above, according to the magnetic disk device of the present invention, the flying height of the slider can be freely adjusted by setting the flying height as the innermost periphery of the data area and setting the yaw angle appropriately. In addition, since the data area can be expanded toward the inner circumference, the capacity of the magnetic disk device can be increased.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the relationship between the write head of a servo writer and the magnetic head of a magnetic disk device according to an embodiment of the present invention, and FIG. 2 is a diagram showing the relationship between the slider and the flying height according to an embodiment of the present invention. 3 is a diagram showing the configuration of a general magnetic disk device, FIG. 4 is a diagram showing the relationship between the write head of a conventional servo writer and the magnetic head of a magnetic disk device, and FIG. 5 is a diagram showing the configuration of a conventional magnetic disk device. FIG. 4 is a diagram showing the relationship between the amount and the yaw angle. 1...Magnetic disk, 3...Magnetic head, 5...
Slider, 6... Carriage, 9... Data area, 10... Magnetic head of servo writer, 12... Slider of servo writer, 21... Position reference signal (servo data), 22... Azimuth.

Claims (1)

[Claims] A magnetic disk device that controls the position of the magnetic head by reading servo data recorded on the servo surface of the magnetic disk using a magnetic head equipped with a slider that is rotatably driven by a rotating carriage and floats as the magnetic disk rotates. A magnetic disk with servo data recorded on the servo surface by a servo writer having a rotation radius larger than the rotation radius of the magnetic head, and a yaw angle at the innermost circumference of the data area of the magnetic disk with the servo data as a reference. A magnetic disk device comprising: means for reading with the magnetic head having a set slider; and position control means for controlling the position of the magnetic head based on the read servo data.