JPH09161249A - Magnetic disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic disk device capable of detecting a position signal from data information and performing high speed and precise seek operation and track follow-up operation. SOLUTION: An azimuth head is a composite magnetic head provided with recording exclusive elements 2a, 2b and reproducing exclusive elements 1a, 1b. An AGC/track code recording area 8 consists of an AGC setting part 3 deciding an amplification factor of a regenerative output of a reproducing head, an erase part 4, a track code part 5 coding a track number and recording it and a mark part 6. A data information recording area 9 records the same data making an azimuth angle at an angle positive/negative different from each other on a pair of half tracks respectively. When the head traverses the data, a phase difference occurs between regenerative outputs of the reproducing elements 1a, 1b, and by combining the phase difference signal and the track number, the position signal continuous to all tracks is obtained. The head is positioned based on the position signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and more particularly to a magnetic disk device for detecting a track position by using information written in a data track.

[0002]

2. Description of the Related Art In a magnetic disk device, a servo surface servo system has been conventionally known which positions a data head which moves integrally with a servo head based on a position signal from a dedicated servo surface. This method is suitable for head positioning of a magnetic disk drive that requires high speed and high accuracy because it can obtain a substantially continuous position signal. However, as described above, the data head is positioned only by the position signal of the servo surface. However, there is a drawback that the track position of the data head cannot be correctly detected due to the positional deviation between the servo head and the data head caused by mechanical vibration, thermal expansion, or the like.

On the other hand, there is known a data surface servo system in which a position signal is recorded at a predetermined interval at the head of each sector on the data surface and the data head is positioned based on the position signal. Although this method solves the drawbacks of the servo surface servo method, it cannot secure a sufficient signal band because the position signal is discrete. For this reason, the gain of the control system cannot be increased, and as a result, high-speed and highly accurate positioning cannot be achieved.

The above-mentioned servo surface servo system and data surface servo system have their respective drawbacks. To eliminate these drawbacks, for example, as described in Japanese Patent Laid-Open No. 62-298015, data It is conceivable to use the data itself written in the track as position information.

[0005]

The technique disclosed in Japanese Patent Laid-Open No. 62-298015 among the above-mentioned prior arts prevents magnetic interference between tracks, that is, crosstalk, by the magic mass recording, and further sets the azimuth angle. The two recording / reproducing heads are used to position the heads by using the data of the adjacent recording tracks.

However, this prior art does not disclose a specific method of generating a position signal.

Although it is good to detect the position information and position the head while reading the data, there is a problem in how to detect the position information when writing the data.

Further, although it is good to perform the track following operation on the target track, the seek operation for moving the head to the target track does not have a track number recorded therein, so that there is a problem in high-speed positioning operation. was there.

The present invention has been made in view of the above circumstances, and provides a magnetic disk device capable of detecting a position signal from data information and performing high-speed and highly-accurate seek operation and track following operation. The purpose is to

[0010]

In order to achieve the above object, the magnetic disk device of the present invention has a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles with different recording tracks, respectively. It has a V-shaped recording / reproducing separation type head which is formed in a letter shape and is provided adjacent to the same head, and the head is positioned on an arbitrary track of the magnetic disk by a positioning mechanism to store data. A magnetic disk device for recording / reproducing is characterized in that data is recorded on one recording track of the magnetic disk by a V-shaped magnetization pattern, and a position signal indicating a track position is obtained from the magnetization pattern on which the data is recorded.

Further, in the magnetic disk device of the present invention, a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles having different recording tracks are respectively formed in a V shape, and these are adjacent to each other and are the same. In a magnetic disk device that has a V-shaped recording / reproducing separation type head provided on the head and records / reproduces data by positioning the head on an arbitrary track of the magnetic disk by a positioning mechanism, The recording tracks are characterized by forming an area having the same azimuth angle and an area having different azimuth angles with respect to the adjacent recording tracks.

Further, in the magnetic disk device of the present invention, a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles having different recording tracks are respectively formed in V-shape, and these are adjacent to each other and are the same. In a magnetic disk device that has a V-shaped recording / reproducing separation type head provided on the head and records / reproduces data by positioning the head on an arbitrary track of the magnetic disk by a positioning mechanism, The recording areas are formed so that areas having the same azimuth angle and areas having different azimuth angles with respect to the adjacent recording tracks are alternately arranged at a constant interval.

Further, in the magnetic disk apparatus of the present invention, at least the recording area used for automatic gain adjustment and the track number are identified in the area where the azimuth angle is equal to the adjacent recording tracks for each recording track of the magnetic disk. And a recording area used for.

Further, in the magnetic disk device of the present invention, a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles having different recording tracks are formed in V-shape, respectively, and these are adjacent to each other and are the same. In the magnetic disk device, which has a V-shaped recording / reproducing separation type head provided on the head and which records / reproduces data by positioning the head on an arbitrary track of the magnetic disk by a positioning mechanism, the pair of reproductions It has a phase difference detecting means for detecting a phase difference of the reproduction output of the dedicated element, and a control means for positioning the head at the track center so that the phase difference detected by the phase difference detecting means becomes zero. And

Further, in the magnetic disk device of the present invention, a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles having different recording tracks are formed in a V shape, respectively, and these are adjacent to each other and are the same. In the magnetic disk device, which has a V-shaped recording / reproducing separation type head provided on the head and which records / reproduces data by positioning the head on an arbitrary track of the magnetic disk by a positioning mechanism, the pair of reproductions Phase difference detection means for detecting the phase difference of the reproduction output of the dedicated element, track number detection means for detecting the track number based on the reproduction output of any one of the pair of reproduction-only elements, and the phase difference detection means A position signal generator that generates a position signal that changes substantially linearly with respect to the track position by combining the detected phase difference signal and the track number. And having means, and control means for controlling so as to move the head on the basis of the position signal to a target track.

Further, in the magnetic disk device of the present invention, a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles having different recording tracks are formed in V-shape, respectively, and these are adjacent to each other and are the same. In a magnetic disk device having a V-shaped recording / reproducing separated head provided on the head, and recording / reproducing data by positioning the head on an arbitrary track of the magnetic disk by a positioning mechanism, the magnetic disk is adjacent to the magnetic disk. Track position obtained by positioning the head at the center between the two tracks, recording data on the adjacent two tracks in a V-shaped magnetization pattern at a constant cycle, and reproducing the magnetization pattern recording the data. The head is positioned based on a position signal indicating

Further, in the magnetic disk device of the present invention, when reproducing the position information, the pair of read-only elements simultaneously reproduce signals, and when reproducing data information, the pair of read-only elements are independent. When reproducing the data information and recording the data information, the pair of recording-only elements independently records the data information.

Further, in the magnetic disk apparatus of the present invention, the head is constructed such that two V-shaped holes are provided in the slider, a reproducing element is provided in one of the holes, and a recording element is provided in the other. To do.

[0019]

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

FIG. 1 is a configuration diagram of a magnetic recording pattern on a magnetic disk surface by a magnetic disk device according to the present invention. In the present invention, the magnetic head is formed in a V shape,
Recording-only elements 2a and 2b and playback-only elements 1a and 1
A composite magnetic head provided with b is used. For example, a magnetic induction type element is used as a recording-only element, and the element 2a and the element 2b are paired at a constant azimuth angle to record data.

The read-only element is, for example, an MR (Magneto-Resistive) head utilizing the magnetoresistive effect or a GMR.
A (Giant-Magneto-Resistive) head is used, and the element 1a and the element 1b are paired to reproduce data at a constant azimuth angle. The advantage of the MR head is that a reproduction output that does not depend on the peripheral speed of the disk can be obtained, and by separating the recording head and the reproduction head, each head can be optimized.

According to the present invention, the magnetic recording pattern is recorded in each sector of the AGC / track code recording area 8 and the data information recording area 9 with the disk surface as the center of rotation of the spindle motor. In the figure, the data tracks are described from the first track 10 to the third track 12. Data information recording area 9 in each track
Are divided into half tracks, and the same data in which the azimuth angles are formed at positive and negative angles are recorded.

In the AGC / track code recording area 8,
An AGC (automatic gain adjustment) setting unit 3 for determining the amplification factor of the reproduction output of the reproducing head, an erase unit 4 for identifying the AGC / track code recording area, a track code unit 5 for coding and recording a track number, and , A mark portion 6 for identifying the index or the sector.
Information is recorded in the AGC / track code recording area 8 by using the recording element 2a. In particular, the AGC setting unit 3
Records continuously across tracks. Conversely, the recording element 2b may be used to perform recording with an azimuth angle of opposite sign.

Further, as shown in FIG. 6, the read-only element 1
The AGC setting section a: 13 and the track code section a: 15 corresponding to a may be provided, and further, the AGC setting section b: 14 and the track code section b: 16 corresponding to the read-only element 1b may be provided. Thereby, the reliability of the reproduced signal can be improved.

FIG. 2 is a block diagram of a magnetic disk device according to the present invention. In this magnetic disk device, when a recording or reproducing command is sent from the central controller 21 (CPU) to the disk controller 22, the disk controller 22 instructs the microcomputer 23 to move the head to a target track. A magnetic disk 28 is attached to a shaft 30 driven by a spindle motor, and a head 31 floats above the disk surface with a slight gap. The head 31 has a head support system 32.
The head support system 32 is fixed to the voice coil motor 27. With the movement of the voice coil motor 27, the head 31 moves about the rotation shaft 33,
The disk 28 is moved from the outer circumference to the inner circumference or the opposite direction to read or write the data recorded on the track of the disk 28.

To record data on a target track, the data is written from the disk controller 22 to the write circuit 36.
After being sent to the write circuit 36 and subjected to code conversion by the write circuit 36, the same data is respectively written through the write amplifiers 34 and 35 by the recording elements 2a and 2b to generate a magnetic field at the same time to perform recording on the disk surface.

On the other hand, in reproducing the data from the target track, the change of the magnetic field is detected by the reproducing element 1a, and the amplitude of the output waveform of the AGC setting section 3 of FIG. It is fixed on the track.

On the other hand, the reproducing element 1b similarly detects the change in the magnetic field, sets the amplification factor of the reproduction output amplitude set by the AGC amplifier 39 by the AGC gain setting circuit 40 via the reading amplifier 38, and amplifies it. To do.

The data pulse generating circuit 41 is shown in FIG.
A peak pulse at the magnetization reversal point is generated for the waveform obtained by adding the reproduction output a: 50 of the reproduction element 1a and the reproduction output b: 51 of the reproduction element 1b. The VFO circuit 42 opens a discrimination window, and the data discrimination circuit 43 generates a reproduction code of 1,0.

In the phase difference detection circuit 45, the reproduction output a: 5
The phase difference between 0 and the reproduction output b: 51 is detected. In the present invention, this phase difference signal becomes the head position signal. This principle will be described later in detail. This position signal is converted to ADC: 46
Analog-to-digital conversion with the microprocessor 2
Capture with 3.

In the microprocessor 23, a control input for moving the head or causing the head to follow the center of the target track is generated in accordance with a command for moving the head to the target track sent from the disk controller 22. . When moving between tracks, the track number and phase difference detection circuit 45 obtained from the track code generation circuit 44
By superimposing the head position signals obtained from the above, continuous position signals are generated for all tracks, a speed signal is generated based on that signal, and speed feedback is used to move to the vicinity of the target track. To do. In the vicinity of the target track, the track tracking control is switched to, and the target track center is tracked by the position control so that the head position signal obtained from the phase difference detection circuit 45 becomes zero.

The DAC: 25 converts the control input from digital to analog and applies it to the VCM drive circuit 26,
The voice coil motor 27 is driven.

FIGS. 3, 4 and 5 are response waveforms of the reproduction output a: 50 of the reproduction element 1a and the reproduction output b: 51 of the reproduction element 1b when the head crosses the magnetic recording pattern of the present invention. Here, the pattern of the track code part is omitted.

FIG. 3 shows reproduction outputs of the reproduction elements 1a and 1b when the reproduction element is located at the center of the n track. At this time, the AGC setting section 3 sets the AGC gain setting only to the reproduction output a. Appears, and the data information recording area 9 outputs a waveform in which the phases of the reproduction outputs of the reproducing element 1a and the reproducing element 1b are completely the same. Therefore, the head position signal output from the phase difference detection circuit 45 in FIG. 2 becomes zero.

FIG. 4 shows reproduced waveforms of the reproducing elements 1a and 1b when the reproducing elements 1a and 1b are deviated by ¼ track in the negative direction with respect to the track center.
When the head reaches the data information recording area, the reproducing output of the reproducing element 1a becomes maximum first, and then the reproducing element 1b.
The playback output of is maximized. The output of the phase difference detection circuit 45 then produces a positive phase difference signal.

On the contrary, FIG. 5 shows that the reproducing elements 1a and 1b are ¼
The reproduced waveforms of the reproducing elements 1a and 1b in the case of being displaced in the plus direction with respect to the track center by the track amount are shown. When the head reaches the data information recording area, the reproduction output of the reproduction element 1b becomes maximum first, and then the reproduction output of the reproduction element 1a becomes maximum. The output of the phase difference detection circuit 45 then produces a negative phase difference signal. Based on the above principle, it is possible to generate a linear position signal in the track.

As described above, according to the embodiment of the present invention, the track number obtained from the track code generation circuit 44 and the head position signal from the phase difference detection circuit 45 are overlapped, so that the continuous position can be obtained for all tracks. Generate a signal. This principle is shown in FIG. In the figure, of the head position signals obtained from the phase difference detection circuit 45, the position signals on even-numbered tracks are inverted to generate continuous track position signals. A continuous position signal is obtained by adding the track number obtained from the track code generation circuit 44 to this in-track continuous position signal. A track seek operation and a track following operation are performed using this continuous position signal.

The track seek operation may be performed by using a continuous position signal, and the track following operation may be performed by using a continuous track hitting position signal to perform head positioning.

If the data recording method is the 1-7 code, the maximum number of data that does not cause magnetization reversal is 7. For example, if the data is recorded at 50 MHz, the output sampling of the phase difference detection circuit is 16.6 MHz at the minimum and 50 MHz at the maximum. In the ordinary sector servo system, the maximum sampling frequency of the control system is considered to be 20 KHz in consideration of the recording efficiency of the disk surface.

On the other hand, according to the present invention, since the sampling frequency is 16.6 MHz at the minimum, there is a difference of 1000 times in the sampling frequency. Therefore, a plurality of, for example, 100 phase difference signals may be smoothed and output as position signals.

As a result, the noise component contained in the position signal is reduced and the detection accuracy is improved. Therefore, highly accurate track following operation becomes possible.

FIG. 8 is a structural diagram of a magnetic recording pattern on a magnetic disk surface by the magnetic disk device according to the present invention. The difference from the configuration of FIG. 1 is that a servo unit 18 is provided in the sector information. Reproduction-only elements 1a, 1b
Is an AGC setting unit 3, a track code unit 5, a servo unit 1
After passing through 8, the track is positioned in the center between the 3rd and 4th tracks in the figure, and thereafter, data is recorded and reproduced in the data information storage area 9.

Data recording is performed by recording-only elements 2a and 2
Record independently with b. In FIG. 8, the recording-only element 2a records on three tracks, and the recording-only element 2b records on four tracks. Similarly, read-only elements 1a and 1b
Also reproduces data independently. With this configuration, the data recording area can be substantially doubled.

FIG. 9, FIG. 10 and FIG. 11 show an example of an embodiment of a method of manufacturing a magnetic head. 9 is an external view as seen from the lower surface of the slider, FIG. 10 is an external view as seen from the upper surface, and FIG. 11 is a sectional view of the slider.

In these figures, a slider 70 is provided with a through hole 77 for reproduction and a through hole 78 for recording in a V-shape to form a so-called planar type head element. Around the holes 77 and 78, yokes 71 and 72 are made of permalloy or the like, respectively.

An MR element 75 is used as the reproducing element, and a magnetic induction type coil 76 is used as the recording element. 74 is a spacer for separating the recording element and the reproducing element. For example, when reproducing data information on the disk surface, the through hole (gap) 77 detects the magnetic field on the disk surface and changes the resistivity in the MR element 75. Yoke 7 for MR element
A constant current is supplied to each of the reproducing element 1a and the reproducing element 1b from the electrode 73 above 1, and the change in resistance can be detected as a change in voltage.

On the other hand, in order to record data information on the disk surface, a voltage is applied to the electrode 73 on the yoke 72 to generate a magnetic field in the coil 76. This magnetic field is recorded on the disk surface through the yoke 72. Further, in FIG. 11, M
Although the R element 75 and the magnetic induction coil 76 are formed on the same plane, they may be laminated.

Although the horizontal magnetization method has been described as an example, the present invention is not limited to this method and can be applied to, for example, a vertical magnetization method.

Although the present embodiment is premised on positioning the head by digital control, it is also possible to construct a control filter for phase control by an analog circuit without using a microprocessor. It is possible.

In addition to the magnetic disk device, the present invention uses the magnetization pattern used in the present invention,
It is also possible to apply it to a positioning device of another storage medium device.

[0051]

As described above, according to the present invention, since the data itself recorded on the data track can be used as the track position signal, the servo information dedicated to the track position detection is recorded as in the conventional case. You don't need the area to do it.

Furthermore, according to the present invention, since the magnetic pattern is provided with the AGC setting area, a stable reproduction signal is obtained, and since the track code portion is provided, a linear continuous signal is generated when the head moves between tracks. Is obtained.

As described above, according to the present invention, it is possible to increase the storage capacity of a storage medium such as a magnetic disk and to improve the accuracy and speed of head positioning.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an example of a magnetic recording pattern on a disk surface by a magnetic disk device according to the present invention.

FIG. 2 is a block diagram showing an example of an embodiment of a magnetic disk device according to the present invention.

FIG. 3 is a waveform diagram showing a reproduced waveform of a head by the magnetic disk device according to the present invention.

FIG. 4 is a waveform diagram showing a reproducing waveform of a head by the magnetic disk device according to the present invention.

FIG. 5 is a waveform diagram showing a reproduced waveform of a head by the magnetic disk device according to the present invention.

FIG. 6 is a configuration diagram showing another example of the magnetic recording pattern on the disk surface by the magnetic disk device according to the present invention.

FIG. 7 is an explanatory diagram showing a principle of generating a continuous position signal in the magnetic disk device according to the present invention.

FIG. 8 is a configuration diagram showing another example of the magnetic recording pattern on the disk surface by the magnetic disk device according to the present invention.

FIG. 9 is an external view of the head of the magnetic disk device according to the present invention as seen from the lower surface of the slider.

FIG. 10 is an external view of the head of the magnetic disk device according to the present invention, as viewed from the lower surface of the slider.

FIG. 11 is a cross-sectional view of the slider of the head portion of the magnetic disk device according to the present invention.

[Explanation of symbols]

 1a reproducing element 1b reproducing element 2a recording element 2b recording element 3 AGC setting section 4 erase section 5 track code section 6 mark section 8 AGC / track code recording area 9 data information recording area 10 tracks 11 tracks 12 tracks 13 AGC setting section a 14 AGC setting section b 15 Track code section a 16 Track code section b 18 Servo section 21 CPU 22 Disk controller 23 Microcomputer 28 Disk 34 Writing amplifier 35 Writing amplifier 36 Writing circuit 37 Reading amplifier 38 Reading amplifier 39 AGC amplifier 40 AGC gain setting circuit 41 data pulse generation circuit 44 track code generation circuit 45 phase difference detection circuit 50 reproduction output a 51 reproduction output b 70 slider 71 reproducing element yoke 72 recording element Child yoke 73 Electrode 75 MR element 76 Magnetic induction coil 77 Reproduction through hole 78 Recording through hole

Claims (9)

[Claims] 1. A V-shape in which a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles with different recording tracks are formed in V-shapes, and these are adjacently provided in the same head. In a magnetic disk device that has a recording / reproducing separated type head, and records / reproduces data by positioning the head on an arbitrary track of a magnetic disk by a positioning mechanism, a V-shaped recording track is formed on one recording track of the magnetic disk. A magnetic disk device characterized in that data is recorded by a magnetization pattern, and a position signal indicating a track position is obtained from the magnetization pattern in which the data is recorded. 2. A V-shape in which a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles with different recording tracks are formed in V-shapes and these are adjacently provided in the same head. Type recording / reproducing separated type head, in which the head is positioned on an arbitrary track of a magnetic disk by a positioning mechanism to record / reproduce data, a recording track adjacent to each recording track of the magnetic disk A magnetic disk drive characterized in that a region having an equal azimuth angle and a region having a different azimuth angle are formed with respect to. 3. A V-shape in which a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles with different recording tracks are formed in V-shapes and these are adjacently provided in the same head. Type recording / reproducing separated type head, in which the head is positioned on an arbitrary track of a magnetic disk by a positioning mechanism to record / reproduce data, a recording track adjacent to each recording track of the magnetic disk On the other hand, the magnetic disk device is characterized in that the recording areas are formed such that areas having the same azimuth angle and areas having different azimuth angles are alternately arranged at a constant interval. 4. A recording area used for automatic gain adjustment and a recording area used for discriminating a track number are at least provided in an area having the same azimuth angle with respect to the adjacent recording tracks for each recording track of the magnetic disk. 4. The magnetic disk device according to claim 1, further comprising: 5. A V-shape in which a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles with different recording tracks are formed in V-shapes and these are adjacently provided in the same head. A recording / reproducing separated type head, and recording / reproducing data by positioning the head on an arbitrary track of a magnetic disk by a positioning mechanism, the position of reproduction output of the pair of reproduction-only elements A magnetic disk device comprising: a phase difference detecting means for detecting a phase difference; and a control means for positioning the head at the track center so that the phase difference detected by the phase difference detecting means becomes zero. 6. A V-shape in which a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles with different recording tracks are formed in V-shapes, and these are adjacently provided in the same head. A recording / reproducing separated type head, and recording / reproducing data by positioning the head on an arbitrary track of a magnetic disk by a positioning mechanism, the position of reproduction output of the pair of reproduction-only elements A phase difference detecting means for detecting a phase difference, a track number detecting means for detecting a track number based on a reproduction output of any one of the pair of read-only elements, and a phase difference signal detected by the phase difference detecting means. Position signal generating means for generating a position signal that changes substantially linearly with respect to the track position by combining with the track number; Magnetic disk apparatus characterized by a control means for controlling to move the head to the target track. 7. A V-shape in which a pair of read-only elements and a pair of write-only elements corresponding to two azimuth angles with different recording tracks are formed in V-shapes and these are adjacently provided in the same head. Type recording / reproducing separated type head, in which the head is positioned on an arbitrary track of the magnetic disk by a positioning mechanism to record / reproduce data, a center between two adjacent tracks of the magnetic disk Position the head on the
A magnetic disk device characterized in that data is recorded at a constant cycle in a letter-shaped magnetization pattern, and a head is positioned based on a position signal indicating a track position obtained by reproducing the magnetization pattern recording the data. 8. When reproducing the position information, the pair of read-only elements simultaneously reproduce signals, and when reproducing data information, the pair of read-only elements independently reproduce data information, 8. The magnetic disk device according to claim 7, wherein when the data information is recorded, the pair of write-only elements independently record the data information. 9. The head according to claim 1, wherein the slider is provided with two V-shaped holes in a slider, one of which is provided with a reproducing element and the other of which is provided with a recording element. The magnetic disk device described.