JPH0793733A - Hard disk device - Google Patents

Abstract

PURPOSE:To directly record the data on an inductive head without mechanical motive operation by beforehand shifting a reproducing on-track position of an information identification field to an inner peripheral side. CONSTITUTION:Every track is constituted of a first servo signal field 1, a second servo signal field 2, the information identification fields 3-9 and data fields 14-16. A line where positional error signals obtained from the first, the second servo signal fields 1, 2 become minimum corresponds to the outermost peripheral cylinder (0), and passes through the just center of the cylinder (O) information identification field 9. The information identification data 9 of the cylinder (0) and the shift amount 18 of the data exist between with the center 20 of the data field of the cylinder (0), and the direction is formed shifted to the inner peripheral side viewing from the data field. In the cylinder (k) in the vicinity of the center, the shift exists between the data field 13 and the information identification field 13 also, and in the cylinder (n) in the vicinity of the inner periphery, the information identification field 3 and the data field 10 are constituted on one straight line.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard disk drive, and more particularly to a recording in which a recording operation by a thin film inductive head and a reproducing operation by a magnetoresistive effect head are separated and a thin film inductive head and a magnetoresistive effect head are combined. The present invention relates to a hard disk device using a reproduction-separated composite head.

[0002]

2. Description of the Related Art As a recording / reproducing separated type head for high-density recording / reproducing, a conventional thin film inductive head is optimized in a recording mode, and a magnetoresistive effect for optimizing a reproducing function is provided in the vicinity of the head. A so-called composite type head in which heads are arranged is known.

On the other hand, from the viewpoint of the device system, a compact and high-speed hard disk device is required. In the current mainstream compact hard disk drive having a 3.5-inch form factor or less, a rotary positioning mechanism that can reduce the influence of inertia is used as a head positioning mechanism.

In a hard disk drive having a rotary type positioning mechanism, since the access locus of the head is arcuate, a so-called yaw angle, which is a skew with respect to the recording track of the magnetic head slider, is generated from the inner circumference to the outer circumference. Due to this yaw angle, off-track occurs during recording and reproduction.

When the yaw angle increases, the effective track width decreases, and in particular, the flying height of the magnetic head slider that flies over the magnetic disk by the principle of the air bearing decreases. For this reason, there is a limit to the size of the magnetic head slider, and it is considered that a desirable limit is about 15 ° to 20 °.

In particular, when the contact start / stop at the time of starting / stopping is performed, it is said that the yaw angle of the magnetic head slider in the contact start / stop field is as small as possible from the viewpoint of tribology. The maximum yaw angle is often given at the outermost track of the track in connection with the flying height design.

In the recording / reproducing separated type head, since there is a distance between the recording and reproducing heads, the on-track position between recording and reproducing differs especially under the condition that the yaw angle becomes large. In other words, the servo system has to perform positioning on the same target recording track with respect to dedicated heads during recording and during reproduction.
For that purpose, at least it is necessary to clarify, before the head access command, whether to record or reproduce on the target track.

[0008]

The conventional recording / reproducing separated type magnetic head has the following problems because the recording head and the reproducing head are physically separated from each other.

[1] Since the recording gap position and the reproducing position are separated by a level of approximately 10 μm and outside, an error occurs in the time axis position from the rotation synchronization information provided on the track. In a high-density hard disk, the bit length is 1 μm or less, so the distance between the two heads cannot be ignored, and some correction or adjustment algorithm is required.

[2] Since the off-track at the time of recording / reproducing due to the yaw angle, the device controller may be provided with a function for identifying them. However, when performing continuous recording / reproducing operations on the same track. Must be re-positioned, and if the off-track is large, it is difficult to correct the off-track in time, which causes an increase in error or a decrease in throughput.

Further, in the reproducing and recording operations for the sector on the track, the off-track between the thin film inductive head and the magnetoresistive head due to the yaw angle causes a problem in sector identification. That is, since the head for reproducing data is always the magnetoresistive head, whereas the head for recording is the thin film inductive head, the adjacent recording field, the information identification field, is reproduced by the magnetoresistive head. Immediately afterwards, it is necessary to record in the data field. At this time, when the yaw angle is large, the magnetic center of the magnetoresistive effect head and the magnetic center of the thin film inductive head, that is, the geometric center, are offset, so the information identification field for identifying the target cylinder, head number, and sector number. Must be played exactly, and for that
The problem is to minimize the magnetic center offset amount of the thin film inductive head.

However, by simply minimizing the magnetic center offset amount of the thin film inductive head in the outermost track where the yaw angle is generally the maximum, the offset in the track width direction of the information identification field with respect to the data field is obtained. Becomes large, and it becomes difficult to recognize the information identifier and reproduce the data when reproducing.

Another means for minimizing the off-track due to such a yaw angle is to design the distance between the gap of the thin film inductive head and the magnetoresistive head as small as possible. . However, this distance also has its lower limit in order to improve the recording characteristics of the thin film inductive head and the shield characteristics of the magnetoresistive effect head. Especially, the higher the track density, the more the off-track in the information identification field. The quantity will be significant.

An object of the present invention is to minimize the off-track amount between recording / reproducing operations due to the yaw angle by the track layout, regardless of the distance between the thin film inductive head and the magnetoresistive head. An object of the present invention is to provide a hard disk device having a composite head structure capable of minimizing the off-track without sacrificing the device track capacity.

[0015]

The gist of the present invention for achieving the above object lies in the following item 8.

[1] A hard disk device having a magnetic head slider provided with a composite type head composed of a thin film inductive head for recording data and a magnetoresistive head for reproducing data. With respect to the center of the data field in the track width direction of the formed track, the center in the track width direction of the information identification field for identifying cylinder information or sector information is (1) Shifted to the outer cylinder side as seen from the field, (2) Near the outermost cylinder, shifted to the inner cylinder side seen from the data field,
(3) Further, in the intermediate cylinder located between the innermost peripheral cylinder and the vicinity of the outermost peripheral cylinder, the shift amount of the center of the data field near the outermost peripheral cylinder and the vicinity of the innermost peripheral cylinder. A hard disk drive characterized by being determined by interpolation based on a linear approximation using the amount of shift of the center of the data field.

[2] In the vicinity of the innermost cylinder, the shift amount of the center of the data field and the shift amount of the information identification field are set to zero, and the data field and the information identification field are aligned. Formed,
In the vicinity of the outermost cylinder, the information identification field is shifted toward the inner cylinder as seen from the data field, and in the intermediate cylinder, the shift amount of the center of the data field near the outermost cylinder and the maximum The amount of shift of the information identification field in the intermediate cylinder is determined based on interpolation based on linear approximation using the amount of shift of the center of the data field near the inner cylinder. Hard disk device described in.

[3] (1) Near the innermost peripheral cylinder, the center in the track width direction of the information identification field is shifted to the outer peripheral cylinder side when viewed from the data field, and (2) the outermost peripheral cylinder. In the vicinity, the shift amount in the information identification field and the shift amount in the data field are zero, and the information identification field and the data field are formed in a straight line, (3) In the intermediate cylinder, The intermediate cylinder based on an interpolation amount based on the linear approximation using the shift amount of the center of the information identification field near the outermost cylinder and the shift amount of the center of the information identification field near the innermost cylinder. [1] characterized in that the amount of shift of the information identification field in Hard disk device described in.

[4] The absolute value of the shift amount of the information identification field near the innermost peripheral cylinder is equal to the absolute value of the shift amount of the information identification field near the outermost cylinder, The value of the shift amount is a magnetic center offset amount of the thin film inductive head in the track width direction between the geometric center of the thin film inductive head in the recording track width direction and the magnetic center of the magnetoresistive head in the recording track width direction. The hard disk device according to the above [3], wherein the hard disk device is determined from the value of 1/2 of the above.

[5] sin (P1) which is the sine of the yaw angle P1 of the magnetic head slider in the recording data field on the innermost track and sin of the magnetic head slider in the recording data field on the outermost track. A track between the angular offset value P which is 1/2 of the sum of the sine of the yaw angle P2 and sin (P2), the recording gap position of the thin film inductive head and the center position of the magnetoresistive head film thickness. The hard disk drive according to [4], wherein a value of the magnetic center offset amount of the thin film inductive head is formed to be equal to the product S · P of the separation distance S in the circumferential direction.

[6] A servo surface dedicated to the positioning servo is provided as a magnetic pattern on the magnetic disk, and servo signal fields are formed at equal intervals on the servo surface.
The track center position of the servo signal field having the smallest position error signal detected by the servo head on the servo surface and the track center position of the information identification field are formed to coincide with each other. ] The hard disk device described in.

[7] One-phase servo signal fields for head positioning are formed on the data recording surface at equal pitches in the track direction, and the track center of the servo signal field where the position error signal of the servo signal field is minimized. The hard disk drive according to [6], wherein the position and the track center position of the information identification field are formed to coincide with each other.

[8] The shift amount of the center of the information identification field in the track width direction, which is interpolated based on the linear approximation, is approximated to the linear approximation in a plurality of data recording zones divided based on the recording / reproducing frequency. The hard disk device according to the above [1], wherein the median value of the shift amount interpolated based on the above is a constant value.

[0024]

In the hard disk device of the present invention, the rotary head positioning mechanism used in a small hard disk device of 3.5 inches or less causes a problematic yaw angle, which is caused by the distance between the recording head and the reproducing head. Compensate for geometric off-track generation.

The sector information identifier (recognition information) during the recording operation of the recording sector is accurately reproduced. Further, even when recording and reproduction are continuously performed on the same track, the correction operation amount of the off-track is minimized to avoid a decrease in the off-track margin.

The formation is performed by shifting the information identification field near the innermost peripheral cylinder to the outer peripheral cylinder side as seen from the data field. In the vicinity of the outermost cylinder, the information identification field is shifted to the inner cylinder side as viewed from the data field. And in those intermediate cylinders,
These intermediate shifts are given by the amount of interpolation based on the linear approximation.

As a result, when there is a geometrical off-track between the recording and reproducing near the outermost circumference and the information identifier and the data field are always formed in a straight line, 2 μm.
Reduce off-track in the information identifier part reaching
Achieves highly accurate determination in the recording sector.

Further, the amount of the shift is calculated as the sum of the sine of the yaw angle at the outermost circumference and the sine of the yaw angle at the innermost circumference.
The magnetic center position of each of the thin film inductive head and the magnetoresistive head in the track width direction is configured so as to have a value obtained by multiplying the amount corresponding to the separation distance.

Then, the amount corresponding to 1/2 thereof is set as the shift amount, and the off-track between recording and reproduction at the outermost circumference is set to about 1/4 of the conventional method. On the other hand, the off-track becomes almost zero in the vicinity of the central cylinder, the off-track increases in the direction opposite to the track width direction toward the innermost circumference, and the maximum value becomes almost equal to the off-track in the outermost circumference.

As a result, on the entire cylinder surface, the maximum off-track amount of the hard disk drive is about 0.5 micron as calculated in the above case.

That is, since the maximum off-track amount is small, it is possible to reproduce the sector information identifier during recording and reproduction with almost no off-track, and as a result, even when the yaw angle is large, a reproduction error occurs. Can be greatly improved.

[0032]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 13 is a view for explaining the head mechanism in the recording / re-separation type hard disk device according to the present invention.

The composite head 103 in which the thin film inductive head and the magnetoresistive effect head are integrated is formed on one end surface of the ABS surface 104 which is the air bearing surface of the magnetic head slider 37.

FIG. 14 is a diagram showing a detailed composite head structure.

The thin film inductive head is composed of an upper pole 105 of the thin film inductive head and a lower pole 106 of the thin film inductive head existing through the recording gap.
It is composed of

The magnetoresistive effect head 29 is sandwiched by a magnetoresistive effect upper shield 107 and a magnetoresistive effect lower shield 108 to reduce magnetic noise, and the magnetoresistive effect head and the thin film inductive head are made of alumina or the like. By the protective layer 109 constituted,
It is formed on one end surface of the ABS surface 104.

FIG. 15 is a diagram for explaining how the thin film inductive head, which is a recording head, and the magnetoresistive head, which is a reproducing head, are separated in the composite head.

The distance between the thin film inductive head gap 27 and the magnetoresistive head 29 along the recording track is represented by a separation distance (S) 33.

FIG. 7 is a diagram for explaining the generation of the head yaw angle of the hard disk drive having the rotary type head positioning mechanism used in this embodiment.

The magnetic head slider 37 is configured to rotate about the pivot 38 via an actuator mechanism (not shown).

When the head is positioned on the innermost circumferential cylinder 35, the longitudinal direction of the magnetic head slider 37 is located between the geometrical tangential direction of the innermost circumferential cylinder 35 and the innermost circumferential cylinder yaw angle (P1). Holds 102.

The outermost cylinder 36 also has an outermost cylinder yaw angle (P2) 101. The yaw angle here is assumed to be measured clockwise from the tangent line of the track, and is in accordance with the general convention of having positive and negative signs.

FIG. 9 is a diagram for explaining the head-off track caused during recording / reproduction by the yaw angle of the magnetic head slider described in FIG. In the figure, the traveling direction of the disc is also indicated by an arrow.

FIG. 9 shows a situation where the head is just positioned in the outermost peripheral cylinder 36 in FIG. 7 as if the head is looking up from the disk surface. The direction is drawn opposite to FIG. 7.

The center of the data track passes exactly through the center of the thin film inductive head 26 in the recording track width direction,
It is parallel to the disc running direction. However, in FIG. 9, since the outermost peripheral cylinder yaw angle 101 exists, the thin film inductive head 26 is just on track.
In this case, the center of the magnetoresistive head 29 is not on the data track center 28, and an off-track component is generated.

In the actual magnetoresistive effect head, the geometrical magnetoresistive effect head position and the magnetic magnetoresistive effect head apparent position are different, and this is referred to as a magnetoresistive effect head magnetic position 30 in FIG. Shows. The distance between the geometrical magnetoresistive head 29 and the magnetic position of the magnetoresistive head corresponds to the magnetic center of the magnetoresistive head and the magnetic center offset amount 32 of the thin film inductive head. It is known that it mainly depends on the height of the magnetoresistive film viewed from the ABS surface.

Thus, although the magnetic center of the magnetoresistive effect head is different from the geometrical magnetoresistive effect head position, as is apparent from FIG.
In general, the magnetoresistive head magnetic center 31 does not match. Even if they can be matched, the thin film inductive head and the magnetoresistive head change the yaw angle while maintaining the positional relationship as it is, so that at other cylinder positions with respect to the data track center 28. It is obvious that the off-track of the magnetoresistive head occurs.

FIG. 8 is a diagram for explaining the reproduction output characteristics of the magnetoresistive effect head in wide recording and narrow reproduction. By defining the magnetoresistive effect head magnetic center 31 at the center of the maximum output section 34, the following will be described. Shall be explained.

FIG. 1 is a diagram for explaining a data forming pattern according to the first embodiment of the present invention. It will be described that FIG. 1 can quantitatively improve the problem of head-off track between recording and reproduction described above. Here, the track layout on the entire surface of the disk will be described for three typical places.

In FIG. 1, the cylinder number is shown, and the cylinder number is the cylinder (0) in accordance with the general convention. Here, three tracks near the innermost circumferential cylinder n, near the central cylinder k, and near the outermost circumferential cylinder (0) are shown as representatives.

The vicinity of the innermost peripheral cylinder n includes the innermost peripheral cylinder n, and the information identifier and the shift amount of data are judged by the positioning resolution of the head positioning servo with respect to the deviation of the writing position of the magnetization pattern. However, they may be combined as a uniform amount. In this embodiment, a range of about 10 cylinders is used. The central cylinder k and the outermost peripheral cylinder (O) are also central cylinders.
k means a range of about 10 cylinders including the outermost peripheral cylinder (O).

Each track is composed of a first servo signal field, a second servo signal field, an information identification field and a data field.

The information identification field is constructed for the purpose of identifying cylinder information or sector information.

Focusing on the outermost cylinder (0), the line on which the position error signal obtained from the first servo signal field 1 and the second servo signal field 2 is the smallest corresponds to the cylinder (0). , It passes exactly through the center of the information identification field 9 of the outermost cylinder (0).

Between the data field center 20 of the outermost cylinder (0), which is the center of the data field 16 of the outermost cylinder (0), there is an information identifier of the outermost cylinder and a shift amount 18 of data, The direction is configured such that the information identification field is closer to the inner circumference side when viewed from the data field.

Focusing on the cylinder k near the center, there is also a gap between the data field 13 of the center cylinder and the information identification field 6 near the center cylinder, and the data field center 202 of the center cylinder and the information identification of the center cylinder are identified. The shift of the center of the field 6 is the information identifier of the central cylinder and the shift amount 201 of the data, and the information identifier is also shifted to the inner peripheral side when viewed from the data. In the cylinder n near the inner circumference, the information identification field 3 of the innermost cylinder n and the data field 10 of the inner cylinder n are arranged on a straight line.

Track pitch 6.2 μm, recording track width 6.2 μm, magnetoresistive head track width 3.6 μm
m, the separation distance between the thin film inductive head gap and the magnetoresistive head is 7.4 μm, the slider yaw angle is 0 ° near the innermost track, and the yaw angle is 15 ° near the outermost track. Will be explained.

Here, referring to FIG. 9 again, it is apparent that the off-track direction of the magnetoresistive effect head with respect to the thin film inductive head is the inner cylinder side direction.

FIG. 10 shows a thin film inductive head 26.
And the magnetoresistive head magnetic center 31 are on a straight line, and the off-track amount in the outermost cylinder in that case is the separation distance (S) 33 shown in FIG.
Is multiplied by the sine of the outermost cylinder yaw angle 101. According to the previous case, this quantity is about 2 microns.
That is, the reproduction center of the magnetoresistive head, that is, the magnetic center is shifted by 2 microns toward the inner circumference side from the center of the recording data field by the thin film inductive head 26.

The above is the description of the off-track at the outermost circumference.

Generally, in a magnetic disk device, the yaw angle is the largest at the outermost circumference and is often zero at the innermost circumference.
Therefore, when the composite head structure as shown in FIG. 10 is adopted, the magnetic centers of the thin film inductive head and the magnetoresistive head coincide with each other on the track at the innermost circumference, and show the maximum deviation at the outermost circumference. .

Referring again to FIG. 1, the information identification field near the outermost circumference is seen from the data field,
It has been shifted to the inner side. In order to recognize the information identification field, it is important to make the magnetoresistive effect head on-track as much as possible on the information identification field.In the information recording operation, immediately after the information identification field is recognized by the magnetoresistive effect head, Since data must be recorded at predetermined positions and the time between them must be very short, movement compensation cannot be performed mechanically.

However, in the structure of this embodiment, since the reproduction on-track position of the information identification field is shifted to the inner circumference side in advance, even if the yaw angle is large, there is no mechanical movement operation, and the magnetic field is generated. It is possible to recognize the information identifier with the resistance effect head and immediately record the data with the thin film inductive head.

As described above, the yaw angle changes depending on the cylinder position. Therefore, the amount of shift between the information identification field and the data field needs to be variable for each cylinder position.

FIG. 4 corresponds to FIG. 1 in the first embodiment and shows the information identifier and the amount of data shift for each cylinder position.

Correction is made for each cylinder by an amount obtained by linearly interpolating the information identifier of the outermost peripheral cylinder and the shift amount 18 of data, and the information identifier of the innermost cylinder which is zero here and the shift amount of data. Is running.

The shift amount in the cylinder i is specified by the amount indicated by 25.

It is obvious that the above-mentioned shift amount variation between the adjacent cylinders is extremely small due to the increase in the number of cylinders and the miniaturization of the track pitch. Therefore, a perfect linear interpolation amount is shown here. , It suffices that adjustments are made to match the shift amount defined by the interpolated shift amount based on this linear approximation, and there is a fixed shift amount for each of multiple data zones. Is also good. In that case, it is clear from the gist of the present invention that the average shift amount for each of the plurality of data zones may be used as the representative value.

FIG. 2 is a diagram for explaining the data forming pattern of the second embodiment of the present invention.

Here, focusing on the innermost cylinder n,
The line on which the position error signal obtained from the first servo signal field 1 and the second servo signal field 2 is the smallest corresponds to the cylinder n, which passes through just the center of the information identification field 3 of the innermost circumferential cylinder n. There is.

Data field 10 of innermost circumferential cylinder n
The information identifier of the innermost cylinder and the shift amount 17 of the data exist between the center of the data field 19 of the innermost cylinder n and the amount of shift 17 of the data. It is composed in a shape that the fields are close together.

Focusing on the cylinder k near the center, there is also a gap between the data field 13 of the center cylinder and the information identification field 6 near the center cylinder, and the data field center 202 of the center cylinder and the information identification of the center cylinder are identified. The shift of the center of the field 6 is the information identifier of the central cylinder and the shift amount 201 of the data, and the information identifier is also shifted to the outer peripheral side when viewed from the data. In the outermost cylinder (0), the information identification field 9 of the outermost cylinder (0) and the outer cylinder (0)
The data fields 16 of are arranged in a straight line.

Track pitch 6.2 μm, recording track width 6.2 μm, magnetoresistive head track width 3.6 μm
m, the separation distance between the thin film inductive head gap and the magnetoresistive head is 7.4 μm, the slider yaw angle is 0 ° near the innermost track, and the yaw angle is 15 ° near the outermost track. Will be explained.

Here, referring again to FIG. 9, it is apparent that the off-track direction of the magnetoresistive head with respect to the thin film inductive head is the inner cylinder side direction.

Magnetic Center of Magnetoresistive Head If the composite head is constructed so that the magnetic center 31 of the magnetoresistive head coincides with the center 28 of the data track by the magnetic center offset amount 32 of the thin film inductive head, the thin film is formed at the outermost circumference. Obviously, there is no off-track between the inductive head and the magnetoresistive head.

In FIG. 11, in order to realize such an effect, the thin film inductive head 26 and the magnetic center 31 of the magnetoresistive effect head are set so as to be offset in the outer cylinder direction by the magnetic center offset amount of the magnetoresistive effect head. FIG.

The off-track amount in the outermost cylinder in this case can be zero as described above, but if the head moves to the inner circumference as it is, the separation distance (S) 33 shown in FIG. It is easily conceivable that the magnetic position of the magnetoresistive head shifts toward the outer circumference in the innermost circumference by an amount obtained by multiplying the sine of the outermost cylinder yaw angle 101. According to the previous case, this quantity is about 2 microns.

That is, in the innermost circumference, the center of reproduction by the magnetoresistive head, that is, the magnetic center is shifted by 2 microns toward the outer circumference side with respect to the center of the recording data field by the thin film inductive head 26. The above is the description of the off-track embodiment in the innermost circumference.

Also in the structure of this embodiment, since the reproduction on-track position of the information identification field is shifted to the outer circumference side in advance in the innermost circumference, the mechanical movement is performed even if the yaw angle is zero. It becomes possible to recognize the information identifier by the magnetoresistive head and immediately record the data by the thin film inductive head without any operation.

Even in this case, the yaw angle changes depending on the cylinder position, as described above. Therefore, the amount of shift between this information identification field and the data field is
Similarly, it is necessary to be variable for each cylinder position.

FIG. 5 corresponds to FIG. 2 in the second embodiment and shows the information identifier and the amount of data shift for each cylinder position. As is apparent, for each cylinder, the information identifier of the innermost circumferential cylinder and the shift amount 17 of the data, and the information identifier of the outermost circumferential cylinder and the shift amount of the data, which are zero here, are linearly interpolated. Is being corrected.

It is obvious that the above-mentioned shift amount variation between the adjacent cylinders is extremely small due to the reduction of the track pitch and the like. Therefore, although a perfect linear interpolation amount is shown here, this linear approximation is performed. It is obvious that the adjustment should be performed so as to match the shift amount defined by the linear interpolation amount interpolated based on the above.

FIG. 3 is a diagram for explaining the data forming pattern of the third embodiment of the present invention.

Here, focusing on the innermost cylinder n,
The line on which the position error signal obtained from the first servo signal field 1 and the second servo signal field 2 is the smallest corresponds to the cylinder n, which also passes through the center of the information identification field 3 of the innermost cylinder n. ing.

Data field 10 of innermost circumferential cylinder n
The information identifier of the innermost cylinder and the shift amount 17 of the data exist between the center of the data field 19 of the innermost cylinder n and the amount of shift 17 of the data. It is composed in a shape that the fields are close together.

Focusing on the cylinder (0) near the outermost circumference, the data field 1 of the outermost cylinder (0) is also obtained.
6 also exists between the information identification field 9 of the outermost cylinder (0), the center field of the data field 20 of the outermost cylinder (0) and the center of the information identification field 9 of the outermost cylinder (0) , The information identifier of the outermost cylinder (0) and the shift amount 18 of the data, which is the information identifier shifted toward the inner circumference side as viewed from the data. In the cylinder k near the center, the information identification field 6 near the center cylinder and the data field 13 near the center cylinder are arranged on a straight line.

Here, the description will be further added based on the above-mentioned representative numerical example. Here, referring to FIG. 9 again, it is apparent that the off-track direction of the magnetoresistive head with respect to the thin film inductive head is the inner cylinder side direction.

Magnetic Center of Magnetoresistive Head The magnetic center offset 31 of the thin film inductive head does not cause the magnetic center 31 of the magnetoresistive head to coincide with the center 28 of the data track 28. Obviously, the off-track between the thin film inductive head and the magnetoresistive head is smaller than the 2 micron of the first embodiment.

The off-track amount in the outermost cylinder in this case is the separation distance (S) 3 shown in FIG.
3 multiplied by the sine of the outermost cylinder yaw angle 101, and
It can take any value between zero.

At the innermost circumference, the magnetic position of the magnetoresistive head shifts to the outer circumference side, and the value of the magnetic resistance head also shifts to the separation distance (S) 33 shown in FIG.
Any value between zero and the amount multiplied by the sine of 1 can be taken.

Therefore, the absolute value of the shift amount of the information identification field near the innermost circumferential cylinder and the absolute value of the shift amount near the outermost circumferential cylinder are made equal, and the shift amount is the geometric center in the recording track width direction. And the magnetic center in the track width direction between the magnetic center of the magnetoresistive head and the magnetic center in the recording track width direction, a value of 1/2 of the magnetic center offset amount of the thin film inductive head in the track width direction is used to identify the most information. The amount of field and data shift can be reduced, and the off-track of the magnetoresistive head can be minimized not only when recording but also when recognizing the information identifier during reproduction.

This is clear when the information identifier and the absolute value of the shift amount of data in FIG. 6 are compared with FIG. 4 or FIG.

Therefore, in FIG. 6, the shift amounts 17 and 18 have the same absolute value. Furthermore, its absolute value is
From the magnetic positional relationship between the thin film inductive head and the magnetoresistive head in the track direction in the composite cormorant head, Sin (P1), which is the sine of the yaw angle P1 in the innermost track, and the yaw angle P2 in the outermost track.
The angular offset value P defined by 1/2 of the sum of Sin (P2), which is the sine of, and the separation distance S, which is the distance between the thin film inductive head gap and the magnetoresistive effect head film thickness center, S · P Is equal to

The angle offset value P of the magnetic disk device used in this example was examined. The change in the yaw angle from the innermost circumference to the outermost circumference is preferably 10 to 25 degrees, and thus the angle offset value P is 0.175 to 0.423.

FIG. 12 is a diagram for explaining the positional relationship between servo surface servo signals and each recording field when the third embodiment is applied to a magnetic disk device having a servo surface. Servo surface servo signal a shown at 21, servo surface servo signal b shown at 22, servo surface servo signal c shown at 23,
Although each of the servo surface servo signals d shown in 24 exists on a dedicated surface different from the data surface, they are dealt with in the same diagram here for convenience.

Here, it is understood that the servo signals a to d on the servo surface are formed at equal pitches, which is different from the track pitch of the data field on the data surface. However, since the pitch of the servo surface servo signal is the same pitch as that of the servo signal field and the information identification field of the data surface, it is clear that head positioning can be achieved by minimizing each position error signal, which is easy to realize. is there.

This structure is an embodiment of the present invention which has a magnetic recording surface dedicated to servo and is effective for a servo surface servo type hard disk drive in which positioning information is read by a servo head installed on the magnetic recording surface. However, as described in the first to third embodiments, it goes without saying that the effect of the present invention can be obtained by the servo signal of only the data surface without being aware of the servo surface. It is possible enough.

Further, in the embodiments of the present invention, the composite head having the magnetoresistive effect shield is referred to as the composite head, but the existence of the magnetoresistive effect shield is not the gist of the present invention, and for example, the composite head having no upper shield exists. The present invention is effective even when a head or the like is used.

[0100]

In a hard disk drive using a composite head in which a thin film inductive head and a magnetoresistive effect head are integrated, a recording data surface is recorded according to the relative positional relationship between the thin film inductive head and the magnetoresistive effect head of the composite type head in the track width direction. In general, the relative position relationship between the information identification field and the data field is not formed on the same line, but is formed by shifting the information identification field from the data field at the outermost circumference, the innermost circumference, or both. And in the innermost intermediate cylinder, by configuring to interpolate the shift amount of both of them,
It is possible to suppress the head slider yaw caused by the off-track during the recording / reproducing operation due to the yaw angle, and to suppress the reduction in the recognition rate of the information identification field due to the off-track between both heads during the data recording.

Further, by ensuring a sufficient off-track margin, it is possible to obtain a hard disk drive having a small device error rate and excellent throughput.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of a track layout according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a track layout according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of a track layout according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating an information identifier and a shift amount of data in the embodiment shown in FIG.

FIG. 5 is a diagram for explaining the information identifier and the shift amount of data in the embodiment shown in FIG.

FIG. 6 is a diagram for explaining the information identifier and the amount of data shift in the embodiment shown in FIG.

FIG. 7 is a diagram illustrating generation of a head yaw angle in the hard disk device used in the embodiment.

FIG. 8 is a diagram for explaining the magnetic center in the magnetoresistive head used in the example based on off-track.

FIG. 9 is a diagram illustrating the occurrence of relative off-track between the thin film inductive head and the magnetoresistive effect head in the outermost peripheral cylinder used in the example.

FIG. 10 is a diagram illustrating a configuration of a composite head using the embodiment of FIG.

11 is a diagram illustrating the configuration of a composite head using the embodiment of FIGS. 2 and 3. FIG.

FIG. 12 is a diagram illustrating an embodiment in which a servo surface servo system is applied to the present invention.

FIG. 13 is a diagram illustrating a configuration of a composite head used in an example.

FIG. 14 is a diagram illustrating in detail the configuration of the composite head used in the example.

FIG. 15 is a diagram defining a separation distance between recording / reproducing heads in the composite head used in the example.

[Explanation of symbols]

1 First Servo Signal Field 2 Second Servo Signal Field 3 Information Discrimination Field of Innermost Cylinder n 4 Information Discrimination Field of n-1 Cylinder 5 Information Discrimination Field of n-2 Cylinder 6 Information Discrimination Field of Central Cylinder 7 (2) Information identification field of cylinder 8 (1) Information identification field of cylinder 9 Information identification field of outermost cylinder (0) 10 Data field of innermost cylinder n 11 n-1 Data field of cylinder 12 n-2 Cylinder data field 13 Data field near the central cylinder 14 (2) Cylinder data field 15 (1) Cylinder data field 16 Outermost cylinder (0) data field 17 Outermost cylinder information identifier and data shift Quantity 18 outermost circumference Information identifier and data shift amount 19 of the innermost cylinder data field center 20 outermost cylinder data field center 21 servo surface servo signal a 22 servo surface servo signal b 23 servo surface servo signal c 24 servo surface servo signal d 25 Information identifier of cylinder i and shift amount of data 26 Thin film inductive head 27 Thin film inductive head gap 28 Data track center 29 Magnetoresistive head 30 Magnetoresistive head magnetic position 31 Magnetoresistive head Magnetic center 32 Magnetoresistive effect Head magnetic center offset amount 33 Separation distance (S) 34 Maximum output part 35 Innermost peripheral cylinder 36 Outermost cylinder 37 Magnetic head slider 38 Pivot 39 Thin film inductive geometric center 101 Outermost cylinder yo Angle 102 Innermost cylinder yaw angle 103 Composite head 104 ABS surface 105 Thin film inductive head upper pole 106 Thin film inductive head lower pole 107 Magnetoresistive effect head upper shield 108 Magnetoresistive effect head lower shield 109 Protective layer 201 Central cylinder information identifier and data Shift amount 202 Center of the central cylinder data field

Claims (8)

[Claims] 1. A hard disk drive having a magnetic head slider provided with a composite type head comprising a thin film inductive head for recording data and a magnetoresistive head for reproducing data, the magnetic head slider being formed on the magnetic disk. The center in the track width direction of the information identification field for identifying cylinder information or sector information, etc. with respect to the center of the data field in the track width direction of the recorded track is (1) (2) In the vicinity of the outermost cylinder, it is shifted toward the inner cylinder as viewed from the data field. (3) Further, the innermost cylinder and the outermost cylinder are located near the outermost cylinder. In the intermediate cylinder located between, the data near the outermost cylinder Hard disk drive, characterized in that it is determined by the linear approximation to based interpolation using the amount of the center of the shift of the data fields of the central shift amount and near the innermost cylinder of the field. 2. Near the innermost peripheral cylinder, the shift amount of the center of the data field and the shift amount of the information identification field are zero, and the data field and the information identification field are formed in a straight line. In the vicinity of the outermost cylinder, the information identification field is shifted to the inner cylinder side when viewed from the data field, and in the intermediate cylinder, the shift amount of the center of the data field near the outermost cylinder and The amount of shift of the information identification field in the intermediate cylinder is determined based on interpolation based on a linear approximation using the amount of shift of the center of the data field near the innermost cylinder. 1. The hard disk device according to 1. (1) In the vicinity of the innermost peripheral cylinder, the center in the track width direction of the information identification field is shifted to the outer peripheral cylinder side when viewed from the data field, (2) in the vicinity of the outermost peripheral cylinder. Then, the shift amount in the information identification field and the shift amount in the data field are set to zero, and the information identification field and the data field are formed on a straight line. (3) In the intermediate cylinder, the maximum In the intermediate cylinder, based on an interpolation amount based on the linear approximation using the shift amount of the center of the information identification field near the outer cylinder and the shift amount of the center of the information identification field near the innermost cylinder. 2. The amount of shift of the information identification field is determined.
Hard disk device described in. 4. The absolute value of the shift amount of the information identification field near the innermost cylinder is equal to the absolute value of the shift amount of the information identification field near the outermost cylinder, and the shift of the information identification field is The value of the amount of the magnetic center offset amount of the thin film inductive head in the track width direction between the geometric center in the recording track width direction in the thin film inductive head and the magnetic center in the recording track width direction in the magnetoresistive effect head. The hard disk drive according to claim 3, wherein the hard disk drive is determined from a value of 1/2. 5. A yaw angle P1 of the magnetic head slider in the recording data field on the innermost track.
1 / the sum of sin (P1) which is the sine of sin (P1) and sin (P2) which is the sine of the yaw angle P2 of the magnetic head slider in the recording data field on the outermost track.
The angle offset value P which is 2 and the product S · P of the thin film inductive head and the separation distance S in the track circumferential direction between the recording gap position of the thin film inductive head and the central position of the magnetoresistive head film thickness are equal to the thin film. The hard disk drive according to claim 4, wherein the value of the magnetic center offset amount of the inductive head is formed. 6. A servo surface dedicated to positioning servo is provided as a magnetic pattern on a magnetic disk, servo signal fields are formed at equal intervals on the servo surface, and a position error signal detected by a servo head on the servo surface is minimum. 2. The track center position of the servo signal field and the track center position of the information identification field are formed so as to coincide with each other.
Hard disk device described in. 7. A track center position of the servo signal field in which one-phase servo signal fields for head positioning are formed on the data recording surface at equal pitches in the track direction and the position error signal of the servo signal field is minimized. 7. The hard disk device according to claim 6, wherein the track center position of the information identification field is formed to coincide with the track center position. 8. The amount of shift of the center of the information identification field in the track width direction interpolated based on the linear approximation is based on the linear approximation in a plurality of data recording zones divided based on the recording / reproducing frequency. 2. The hard disk device according to claim 1, wherein the median value of the shift amounts interpolated by the above is set to a constant value.