JPH058487B2 - - Google Patents
Info
- Publication number
- JPH058487B2 JPH058487B2 JP14681984A JP14681984A JPH058487B2 JP H058487 B2 JPH058487 B2 JP H058487B2 JP 14681984 A JP14681984 A JP 14681984A JP 14681984 A JP14681984 A JP 14681984A JP H058487 B2 JPH058487 B2 JP H058487B2
- Authority
- JP
- Japan
- Prior art keywords
- servo
- head
- data
- position information
- information
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000005415 magnetization Effects 0.000 claims description 13
- 230000004907 flux Effects 0.000 claims description 5
- 230000010363 phase shift Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 230000002411 adverse Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/48—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
- G11B5/58—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B5/596—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on disks
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/12—Formatting, e.g. arrangement of data block or words on the record carriers
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明は、磁気デイスク装置に関し、特に磁気
デイスクから再生したサーボ信号をもとに、磁気
ヘツド位置を制御するトラツク追従制御方式を用
いた磁気デイスク装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a magnetic disk device, and in particular to a magnetic disk device that uses a track following control method to control the position of a magnetic head based on a servo signal reproduced from a magnetic disk. It is related to the device.
従来、磁気デイスク装置は、サーボ情報読出用
のサーボヘツドでサーボデイスクに記録されてい
るポジシヨン情報のＮ・Ｓ極の変化を検出するこ
とにより、ヘツドがデータデイスクのトラツク中
央となるように、トラツク追従制御を行つてい
る。
Conventionally, magnetic disk drives track-follow so that the head is at the center of the data disk track by detecting changes in the north and south poles of position information recorded on the servo disk using the servo head for reading servo information. It's under control.
ポジシヨン情報となるＮ・Ｓ極は、相互に１ト
ラツクずれた位置に磁化されて、書込まれてい
る。しかし、その書込間隔には、データヘツドが
データデイスクにデータを書込むときの磁気反転
間隔が考慮されていないことから、データ書込時
にデータヘツドから発生する磁束がサーボヘツド
に磁気的干渉を及ぼす量が大きい場合、ある特定
のデータパターンにおいて、トラツク追従制御に
乱れが生じてしまうという問題がある。特に、５
インチデイスクのようにデイスク円板の径が小さ
くなると、この傾向が顕著である。 The N and S poles serving as position information are magnetized and written at positions shifted by one track from each other. However, because the write interval does not take into account the magnetic reversal interval when the data head writes data to the data disk, the magnetic flux generated from the data head when writing data causes magnetic interference with the servo head. When the amount is large, there is a problem in that track following control is disturbed in a certain data pattern. In particular, 5
This tendency becomes more noticeable when the diameter of the disc becomes smaller, such as an inch disc.
本発明の目的は、このような従来の問題を解決
し、簡単で安価な方法により、データヘツドから
サーボヘツドへの磁気的干渉に強いサーボ信号を
得て、安定なトラツク追従制御ができる磁気デイ
スク装置を提供することにある。
The object of the present invention is to solve these conventional problems and to provide a magnetic disk device that can obtain a servo signal that is resistant to magnetic interference from a data head to a servo head using a simple and inexpensive method, and that can perform stable track following control. Our goal is to provide the following.
上記目的を達成するため、本発明の磁気デイス
ク装置は、ポジシヨン情報が書込まれたサーボデ
イスクと、該サーボデイスクからポジシヨン情報
を読出すサーボヘツドと、データ情報の記録・再
生を行なうデータヘツドとを備えた磁気デイスク
装置において、前記サーボヘツドで読出すポジシ
ヨン情報の間隔が、前記データヘツドによる最高
周波数データ情報記録時の磁化反転間隔の偶数倍
となるように、前記ポジシヨン情報を間歇的に記
録し、前記データヘツドによる最高周波数データ
情報記録時に、前記データヘツドから発生する磁
束が、前記サーボヘツドが前記ポジシヨン情報か
ら検出したサーボ信号の電圧波形に同相に重畳さ
れることに特徴がある。
In order to achieve the above object, the magnetic disk device of the present invention includes a servo disk on which position information is written, a servo head that reads position information from the servo disk, and a data head that records and reproduces data information. In the magnetic disk device equipped with the above, the position information is intermittently recorded so that the interval of the position information read by the servo head is an even multiple of the magnetization reversal interval when the highest frequency data information is recorded by the data head, The present invention is characterized in that when the data head records the highest frequency data information, the magnetic flux generated from the data head is superimposed in phase on the voltage waveform of the servo signal detected by the servo head from the position information.
以下、本発明の実施例を図面により説明する。
第１図は本発明の一実施例を説明するための図で
あり、同図ａはサーボデイスク上のサーボ情報の
磁化パターンを示し、同図ｂはサーボヘツドの出
力であるサーボ信号を示し、同図ｃはデータ記録
時に発生する磁化反転信号を示し、また同図ｄは
データ記録時に発生するノイズがサーボ信号に重
畳した場合の波形を示している。
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram for explaining one embodiment of the present invention. FIG. 1a shows a magnetization pattern of servo information on a servo disk, FIG. Figure c shows a magnetization reversal signal generated during data recording, and Figure d shows a waveform when noise generated during data recording is superimposed on the servo signal.
サーボヘツドが検出するポジシヨン情報からヘ
ツドの位置決めに変換を行うには、まず、サーボ
ヘツドが相互に１トラツクずれた位置にＮ極およ
びＳ極それぞれの磁化で書き込まれているボジシ
ヨン情報（第１図ａ参照）を読み出してサーボ信
号を生成し、次に、そのサーボ信号の隣接するピ
ーク電圧の差を監視し、差が零となるようにヘツ
ドの位置を制御する。データ記録時にデータヘツ
ドから発生される磁束は、サーボヘツドに対し
て、ノイズとなつて影響を及ぼす。しかし、サー
ボヘツドがポジシヨン情報から検出したサーボ信
号の電圧波形に対し、同相に重畳するノイズは、
隣接するピーク電圧が互いに打ち消し合う。しか
し、反対の逆相に重畳するノイズは隣接するピー
ク電圧が互いに差を広げてしまうことになる。 To convert the position information detected by the servo head into head positioning, first, the servo head first converts the position information (see Figure 1a), which is written with the magnetization of the north and south poles at positions shifted by one track from each other. ) to generate a servo signal, then monitor the difference between adjacent peak voltages of the servo signal, and control the position of the head so that the difference becomes zero. The magnetic flux generated from the data head during data recording affects the servo head as noise. However, the noise superimposed in the same phase on the voltage waveform of the servo signal detected by the servo head from the position information is
Adjacent peak voltages cancel each other out. However, noise superimposed on the opposite phase increases the difference between adjacent peak voltages.
このことは、ポジシヨン情報の読み出しの間隔
が、データヘツドのデータ記録時に生ずる磁化反
転間隔の奇数倍のときに、磁束はサーボ信号の逆
相で生じる。そのため、重畳したノイズが隣接す
るピーク電圧の値を変動させ、ヘツドの位置制御
に乱れとなつて現われる。 This means that when the position information read interval is an odd number multiple of the magnetization reversal interval that occurs when data is recorded in the data head, the magnetic flux is generated in the opposite phase of the servo signal. Therefore, the superimposed noise causes the values of adjacent peak voltages to vary, resulting in disturbances in head position control.
したがつて、本発明では、第１図ａに示すサー
ボ信号になるポジシヨン情報をサーボデイスク上
に書込むとき、第１図ｃに示すデータヘツドのデ
ータ磁化反転間隔（t2）の奇数倍となる位置を避
けて書き込むことにより、ノイズによる悪影響を
防止している。サーボ情報を第１図ａに示すよう
な磁化パターンに書き込んで、矢印２の方向にサ
ーボデイスクを回転したとき、サーボヘツド１
は、同期情報パターン３、奇数標準ポジシヨン情
報４、偶数標準ポジシヨン情報５、奇数移相位置
誤差情報６、偶数移相位置誤差情報７を読み出し
て、同図ｂに示すようなサーボ信号を出力する。
上記の読み出しが安定動作となるように、サーボ
ヘツド１は、奇数トラツク１２と偶数トラツク１
１の境界線上に追従制御されている。同図ａの同
期情報パターン３は同期合わせに、奇数および偶
数標準ポジシヨン情報（正規位置誤差情報とも呼
ばれる）４，５はヘツドの位置制御に、また奇数
および偶数移相位置誤差情報６，７はシーク時の
速度制御に、それぞれ使用される。 Therefore, in the present invention, when writing the position information that becomes the servo signal shown in FIG. 1a onto the servo disk, the position information that becomes the servo signal shown in FIG . By writing in such a way as to avoid the negative effects of noise, the negative effects of noise are prevented. When servo information is written in the magnetization pattern shown in Figure 1a and the servo disk is rotated in the direction of arrow 2, servo head 1
reads the synchronization information pattern 3, odd standard position information 4, even standard position information 5, odd phase shift position error information 6, and even phase shift position error information 7, and outputs a servo signal as shown in b of the same figure. .
In order to perform the above read operation stably, the servo head 1 has an odd number track 12 and an even number track 1.
Tracking control is performed on the boundary line of 1. Synchronization information pattern 3 in figure a is used for synchronization, odd and even standard position information (also called regular position error information) 4 and 5 are used for head position control, and odd and even phase shift position error information 6 and 7 are used for head position control. Each is used to control the speed when seeking.
第１図ｃの波形は、データヘツドにおける最高
周波数データ記録時の磁化反転信号である。同図
ｂのサーボ信号における奇数標準ポジシヨン情報
４の読み出しピーク値８と偶数標準ポジシヨン情
報５の読み出しピーク値の時間差t1は、同図ｃに
示す磁化反転間隔t2の偶数値６倍である。つま
り、奇数および偶数標準ポジシヨン情報４，５を
サーボデイスク上に書込むときには、デイスクの
回転速度をもとにして、上記のt1となるような位
置に書き込む。また、データヘツドの書き込みデ
ータがMFM（Modified Frequency
Modulation）データコードの場合には、最高周
波数、その1/2または2/3倍の周期数がデータ周期
数になることから、どの場合にも磁化反転１０ま
た１０′の回数が、偶数回あるいはその近傍にな
るようなt1を選ぶ。そうすることによつて、デー
タヘツドからサーボヘツド１のサーボ信号への干
渉が、第１図ｄに示すように、同相なノイズとな
ることから、V1（プラス方向に重畳したノイズ）
あるいはV2（マイナス方向に重畳したノイズ）の
分がサーボ信号の波形に重畳され、隣接するピー
ク電圧値の差には変動が生じないので、ヘツド位
置を決定するための悪影響とはならない。すなわ
ち、奇数および偶数標準ポジシヨン情報４，５の
書き込み位置の関係を、データ記録時の磁化反転
間隔の偶数あるいはその近傍の値にすることによ
り、データ記録時にサーボヘツド１に及ぼすノイ
ズ量に関係なく、良好なサーボ信号を常時得るこ
とができるので、安定なトラツク追従動作が可能
である。 The waveform in FIG. 1c is a magnetization reversal signal when recording data at the highest frequency in the data head. The time difference t 1 between the readout peak value 8 of the odd standard position information 4 and the readout peak value of the even standard position information 5 in the servo signal shown in b of the same figure is 6 times the even value of the magnetization reversal interval t 2 shown in c of the same figure. . That is, when writing the odd-number and even-number standard position information 4, 5 on the servo disk, the information is written at a position corresponding to the above-mentioned t1 based on the rotational speed of the disk. Also, the data written to the data head is written using MFM (Modified Frequency).
Modulation) In the case of a data code, the data cycle number is the highest frequency and 1/2 or 2/3 times the highest frequency, so in any case, the number of magnetization reversals 10 or 10' is an even number or Choose t 1 that is close to that. By doing so, the interference from the data head to the servo signal of servo head 1 becomes in-phase noise as shown in Figure 1d, so V 1 (noise superimposed in the positive direction)
Alternatively, V 2 (noise superimposed in the negative direction) is superimposed on the waveform of the servo signal, and the difference between adjacent peak voltage values does not change, so it does not have an adverse effect on determining the head position. In other words, by setting the relationship between the writing positions of the odd and even standard position information 4 and 5 to an even number or a value close to the magnetization reversal interval during data recording, regardless of the amount of noise exerted on the servo head 1 during data recording, Since a good servo signal can always be obtained, stable track following operation is possible.
以上説明したように、本発明によれば、簡単で
安価の方法により、データヘツドからサーボヘツ
ドへの磁気的干渉に強いサーボ信号が得られるの
で、安定なトラツク追従制御ができる。
As explained above, according to the present invention, a servo signal that is resistant to magnetic interference from the data head to the servo head can be obtained by a simple and inexpensive method, so that stable track following control can be performed.
第１図ａは本発明の一実施例であるサーボデイ
スク上のサーボ情報の磁化パターンを示す図、同
図ｂは、サーボ信号の波形を示す図、同図ｃはデ
ータ記録時の磁化反転信号波形を示す図、同ｄは
データ記録時のノイズがサーボ信号に重畳した場
合の波形図である。
１……サーボヘツド、２……デイスクの回転方
向、３……同期情報パターン、４……奇数標準ポ
ジシヨン情報、５……偶数標準ポジシヨン情報、
６……奇数移相位置誤差情報、７……偶数移相位
置誤差情報、８……奇数標準ポジシヨン情報の読
み出しピーク値、９……偶数標準ポジシヨン情報
の読み出しピーク値、１０，１０′……磁化反転、
１１……偶数トラツク、１２……奇数トラツク。
FIG. 1a is a diagram showing the magnetization pattern of servo information on a servo disk according to an embodiment of the present invention, FIG. 1b is a diagram showing the waveform of the servo signal, and FIG. FIG. 3D is a waveform diagram when noise during data recording is superimposed on the servo signal. 1... Servo head, 2... Disk rotation direction, 3... Synchronization information pattern, 4... Odd standard position information, 5... Even standard position information,
6... Odd number phase shift position error information, 7... Even number phase shift position error information, 8... Read peak value of odd number standard position information, 9... Read peak value of even number standard position information, 10, 10'... magnetization reversal,
11... Even numbered tracks, 12... Odd numbered tracks.
Claims (1)
と、該サーボデイスクからポジシヨン情報を読出
すサーボヘツドと、データ情報の記録・再生を行
なうデータヘツドとを備えた磁気デイスク装置に
おいて、前記サーボヘツドで読出すポジシヨン情
報の間隔が、前記データヘツドによる最高周波数
データ情報記録時の磁化反転間隔の偶数倍となる
ように、前記ポジシヨン情報を間歇的に記録し、
前記データヘツドによる最高周波数データ情報記
録時に、前記データヘツドから発生する磁束が、
前記サーボヘツドが前記ポジシヨン情報から検出
したサーボ信号の電圧波形に同相に重畳されるこ
とを特徴とする磁気デイスク装置。1 In a magnetic disk device comprising a servo disk on which position information is written, a servo head that reads position information from the servo disk, and a data head that records and reproduces data information, position information that is read by the servo head. the position information is intermittently recorded so that the interval is an even multiple of the magnetization reversal interval when the highest frequency data information is recorded by the data head;
When the data head records the highest frequency data information, the magnetic flux generated from the data head is
A magnetic disk device characterized in that the servo head is superimposed in phase with a voltage waveform of a servo signal detected from the position information.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14681984A JPS6126922A (en) | 1984-07-17 | 1984-07-17 | Magnetic disk device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14681984A JPS6126922A (en) | 1984-07-17 | 1984-07-17 | Magnetic disk device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6126922A JPS6126922A (en) | 1986-02-06 |
| JPH058487B2 true JPH058487B2 (en) | 1993-02-02 |
Family
ID=15416244
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14681984A Granted JPS6126922A (en) | 1984-07-17 | 1984-07-17 | Magnetic disk device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6126922A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07114011B2 (en) * | 1988-09-20 | 1995-12-06 | 富士通株式会社 | Servo signal writing method |
-
1984
- 1984-07-17 JP JP14681984A patent/JPS6126922A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6126922A (en) | 1986-02-06 |
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