JPH03256211A - Deterioration deciding system for magnetic head - Google Patents

Deterioration deciding system for magnetic head

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Publication number
JPH03256211A
JPH03256211A JP5399990A JP5399990A JPH03256211A JP H03256211 A JPH03256211 A JP H03256211A JP 5399990 A JP5399990 A JP 5399990A JP 5399990 A JP5399990 A JP 5399990A JP H03256211 A JPH03256211 A JP H03256211A
Authority
JP
Japan
Prior art keywords
magnetic head
test
disk
inspected
magnetic
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.)
Granted
Application number
JP5399990A
Other languages
Japanese (ja)
Other versions
JP2529891B2 (en
Inventor
Sakae Ayabe
栄 綾部
Hiroshi Tanabe
田部 博
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi High Tech Corp
Original Assignee
Hitachi Electronics Engineering Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi Electronics Engineering Co Ltd filed Critical Hitachi Electronics Engineering Co Ltd
Priority to JP2053999A priority Critical patent/JP2529891B2/en
Publication of JPH03256211A publication Critical patent/JPH03256211A/en
Application granted granted Critical
Publication of JP2529891B2 publication Critical patent/JP2529891B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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  • Measuring Magnetic Variables (AREA)
  • Digital Magnetic Recording (AREA)
  • Manufacturing Of Magnetic Record Carriers (AREA)

Abstract

PURPOSE:To prevent working efficiency from falling by writing/reading successively a test signal to/from the track of a disk to be inspected by a magnetic head under the control of a microprocessor, and inspecting a recording meadium by detecting the error of a head signal. CONSTITUTION:Every time a test for S-pieces of the tracks of the disk to be inspected is finished, a reference disk is replaced, and mean read-out voltages V(1), V(2)... for replacement numbers 1, 2... are calculated successively, and is recorded in a memory. If the ratio of the fall of the voltage V is made (k), (k) is calculated by an expression I. The ratio (k) for the number 1, 2,... is either equal to a definite decimal or smaller than it, and it is considered that the performance of the magnetic head falls gradually because of using frequency. This fall is corrected by a correction factor set specially in the microprocessor beforehand. When V(m) falls steeply as shown in a figure, since the ratio (k) for V(m-1) is larger than K, it is decided that the magnetic head is deteriorated, and after the magnetic head is replaced by the good one, the test is started again.

Description

【発明の詳細な説明】 [産業上の利用分野] この発明は、磁気ヘッドの劣化を判定する方式に関し、
詳しくは磁気ディスクサーテイファイヤによる磁気ディ
スクの検査中に、磁気ヘッドの劣化を判定する方式であ
る。
[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for determining deterioration of a magnetic head.
Specifically, this is a method for determining deterioration of a magnetic head while inspecting a magnetic disk using a magnetic disk certifier.

[従来の技術] 情報の記録媒体として多用されているハード磁気ディス
クは、少産り程において磁気ディスクサーfイファイヤ
(以下単にサーテイファイヤという)により記録媒体の
品質が検査される。検査においては適当な周波数のテス
ト信号がトラックに書き込まれ、これを読み出して各種
の項目について検査が行われる。トラック数が多いので
検査は長時間を必要とし、これを短縮するために媒体エ
リアを2分割し、表裏の両面を並列に検査する方式が行
われている。
[Prior Art] Hard magnetic disks, which are frequently used as information recording media, are inspected for quality by a magnetic disk surifier (hereinafter simply referred to as a certifier) when they are produced in small quantities. In the inspection, a test signal of an appropriate frequency is written on the track, which is read out and inspected for various items. Since the number of tracks is large, inspection requires a long time, and in order to shorten this time, a method is used in which the medium area is divided into two and both the front and back sides are inspected in parallel.

i2図(a)〜(d)は、エリア2分割両面並列検査方
式によるサーテイファイヤのmsと検査シーケンスの1
例を示す。図(a)、(b)において、被検杏の磁気デ
ィスク(以ドljに検査ディスクという)1の記録媒体
の範囲は外周エリアlaと内周エリアlbに2分割され
、谷エリアの両面に対してそれぞれ磁気ヘッド部2−1
.2−2が設けられる。各磁気ヘッド部2の磁気ヘッド
(HI)t 、 HD2 )2a−1および磁気ヘッド
(Hl)1 、 HD2 ) 2a2はそれぞれキャリ
1フ機構2b−11よび2b−2により、外周エリア1
aおよび内周エリア1bの111!I tfoのトラッ
クを7−りする。図(c)はサーテイファイヤθ)−/
 I+、、、り構bkを小ず1.8磁′べ(ヘッド2;
1に対し’L’ I!き込み−r” 7ゾJ 11 、
!:l’jき込み制御回路3c、および読み出しアンプ
3bとエラー検出回路3dよりなる同一の検関部3がそ
れぞれ接続される。マイクロプロセッサ4の制御により
、検査ディスク1を同転してトラックシーク機構6によ
り各エリアのトラックがシークされ、コントローラ5の
制御により、シークされた各トラックに対するテスH,
i’yの、呻き込み/読み出しが111列に行われる。
i2 Figures (a) to (d) show the ms of the certifier and test sequence 1 using the two-area two-sided parallel test method.
Give an example. In Figures (a) and (b), the range of the recording medium of the test apricot's magnetic disk (hereinafter referred to as the test disk) 1 is divided into an outer circumferential area la and an inner circumferential area lb, and on both sides of the valley area. For each magnetic head section 2-1
.. 2-2 is provided. The magnetic head (HI) t , HD2 ) 2a-1 and the magnetic head (Hl) 1 , HD2 ) 2a2 of each magnetic head section 2 are connected to the outer peripheral area 1 by carrier mechanisms 2b-11 and 2b-2, respectively.
a and 111 in inner area 1b! Download the Itfo track. Figure (c) shows the certifier θ)−/
I+,..., structure bk with a small size 1.8 magnetic head (head 2;
'L' I for 1! Kikomi-r” 7zo J 11,
! :l'j reading control circuit 3c, and the same checking section 3 consisting of a read amplifier 3b and an error detection circuit 3d are connected to each other. Under the control of the microprocessor 4, the test disk 1 is rotated simultaneously and the track in each area is sought by the track seek mechanism 6, and under the control of the controller 5, the test H,
i'y is read/written in column 111.

サーテイファイヤにおいては、まずテスF 4J? ”
:の彼+t’6値を検出して媒体の記録P1・能が計測
され、さらにデス14,1号のエラーに関するテストが
行われる。図(d)はエラーテストに対するシーケンス
を示す。別途にえられる検査ディスクの回転角度の基準
点をボすインデックス(INI)EX)信号により、検
査ディスクの1回転ごとに、各エリアの両面のトラック
がシークされ、谷トラックに対して谷、自:き込み制御
回路3cによりテスト(,1号が鮮き込まれる。ついで
エラー検出1す1路3dにより次の項り、Iが検査され
る。図小の)Hi均電ハ1jlll ’Mにおいてはテ
スト4+jS’Jの波高植を検出してその平均?h 1
1’をマイクロプロセッサ4によりC?出する。この平
均電比を基準イ1αとして符号のミッシング(Mis)
エラーテスト、およびモジュレーンヨ7 (MOD)テ
ストが行われる。これが終了するとテス) 4:1号が
消失され、続いて符号の湧き出しくEXT)エラーがテ
ストされる。以−ににより1トラツクのテストが終了し
、次のトラックが町1次にシークされて1・、記のシー
ケンスが繰り返され、すべてのトラックがテストされる
Regarding Certifier, first of all, Tess F 4J? ”
The recording P1/performance of the medium is measured by detecting the +t'6 value of :, and a test regarding the error of No. 14, 1 is further performed. Figure (d) shows the sequence for error testing. Each rotation of the test disk, tracks on both sides of each area are sought, and the tracks on both sides of each area are sought by the separately obtained index (INI) signal that marks the reference point of the rotation angle of the test disk. : The writing control circuit 3c writes a test (No. 1 is written.Then, the error detection 11 path 3d checks the next item, I. Is it the average of test 4+jS'J wave height detection? h1
1' by microprocessor 4. put out Missing sign (Mis) using this average electric ratio as a reference i1α
An error test and a Modulane Yo7 (MOD) test are performed. Once this is done, the code 4:1 is erased and the code is subsequently tested for errors. This completes the test of one track, the next track is sought after the first track, and the sequence 1., is repeated, and all tracks are tested.

[解決しようとする課題] さて、1.記の媒体検査においてはコ然、磁気6111
1体の機能、性能に異常がないことが前提である。しか
し、多数のトラックまたは検査ディスク数に対してテス
トを市ねるときは、その使用頻度により磁気へノド2a
は性能が漸次に低下する。
[Problem to be solved] Now, 1. Of course, in the media inspection described above, magnetic 6111
The premise is that there is no abnormality in the function or performance of the unit. However, when testing a large number of tracks or disks to be tested, depending on the frequency of use, it is necessary to
performance gradually decreases.

また、テスト中にキャリッジ機構の動作不良や接合デ5
fスクの表面の異常などにより急激に劣化する場合があ
る。↑11能低下に対しては、ある描度の範囲ではY・
め袖+E係数を設定して読み出し電比が61口1され、
劣化に対しては磁気ヘッドを交換することが’4jわれ
でいる。以1“、に対する従来の判定方法は、検査ディ
スクごとに、その検査初期におけるテスト(+’j ”
’Jの・11均、涜み出し電11(を判定〕人準とし、
テストの追打に従って検査ディスクの適当な枚数ごとの
〜11均読み出し電I「をこの判定基準と比較し、両者
の差か 定の範囲内にあるか内かにより、劣化を判定す
るものであった。しかしながら、このような判定方法は
的確でない。その理由は各検査ディスクには11己録↑
牛能にバラツキがあり、また、検査初期における磁気ヘ
ッドが裏金であるとの保+tiEがないので、上記の判
定μ中は妥当ではない。
Also, during the test, malfunctions of the carriage mechanism and joint defects were detected.
It may deteriorate rapidly due to an abnormality on the surface of the f-screen. ↑11 Regarding the decline in ability, Y・
By setting Mesode + E coefficient, the readout electric ratio is 61 units,
In response to deterioration, we have always replaced the magnetic head. The conventional judgment method for ``1'' is based on the test (+'j ''
'J's 11th uniform, 11th yen,
The deterioration is determined by comparing the ~11-yen readout voltage I'' for each appropriate number of test disks with this judgment standard according to the additional hits of the test, and determining whether the difference between the two is within a certain range or not. However, this method of judgment is not accurate.The reason is that each test disk contains 11 self-records↑
Since there are variations in performance and there is no guarantee that the magnetic head is a back metal at the initial stage of the test, the above judgment μ is not valid.

一方、最近使用されている薄膜ヘッドはやや脆刺である
ので、上記した理由により検査中に急激に劣化する事態
がしばしば発生している。このような劣化した磁気ヘッ
ドによる検査データは信頼tILが低くて再検査を必要
とするが、劣化が速やかに検出されないために、再検査
のロスが大きくて検査効率が低下する弊害があった。
On the other hand, since the thin film heads used recently are somewhat brittle, they often deteriorate rapidly during inspection due to the above-mentioned reasons. Inspection data from such deteriorated magnetic heads has a low reliability tIL and requires re-examination, but since the deterioration is not detected promptly, re-examination losses are large and inspection efficiency is reduced.

この発明は以上に鑑みてなされたもので、サーテイファ
イヤに山、しい判定j、I: ’/’を設定し、磁気ヘ
ッドの劣化を的確、かつ速やかに判定し、劣化が発生し
たときは、直ちに磁気ヘッドを交換して検査ロスを最小
限にとどめるための磁気ヘッドの劣化判定方式を提供す
ることを目的とするものである。
This invention was made in view of the above, and sets a mountain, a correct judgment j, I: '/' in the certifier, accurately and promptly judges the deterioration of the magnetic head, and when deterioration occurs, It is an object of the present invention to provide a method for determining deterioration of a magnetic head so that the magnetic head can be replaced immediately and inspection loss can be minimized.

[課題を解決するためのp段コ この発明は、マイクロプロセッサの制御のもとに、磁気
ヘッドにより被検査ディスクのトラックに対して逐次テ
スト信号の書き込み/読み出しを4iい、読み出しされ
たテスト(it S’jのエラーを検出5− 6 して記録媒体を検査するサーテイファイヤにおける磁気
ヘッドの劣化判定方式である。検査ディスクの適当な個
数のトラックに対するテストの終了ごとに、検査ディス
クに代わって、標準的な記録性能をイ]する基準磁気デ
ィスク(以ド単に基準ディスクという)を置き換えて判
定基準とする。置き換えられたJ、U +′v’ディス
クの1トラツクに対するテスト信弓の・1ノ均読み出し
電IIを算出して逐次比較し、これが−一定の小さい比
率で低下するときは仙用類度による磁気ヘッドの性能の
低下と判定し、大きい比ヰ(て急激に低トシたとき磁気
ヘッドか劣化したと判定するものである。
[P-stage method for solving the problem] This invention sequentially writes/reads test signals to and from tracks of a disk to be inspected using a magnetic head under the control of a microprocessor, and reads out test signals ( This is a method for determining the deterioration of a magnetic head in a certifier that detects errors in S'j and inspects recording media.After each test on an appropriate number of tracks on a test disk, a Then, a reference magnetic disk (hereinafter simply referred to as the reference disk) with standard recording performance is replaced as the judgment standard. 1 average readout voltage II is calculated and compared successively, and when it decreases at a certain small ratio, it is determined that the performance of the magnetic head has deteriorated due to the sensitivity level, and it is determined that the performance of the magnetic head has decreased due to the sensitivity level. It is determined that the magnetic head has deteriorated.

[作用] 以トのこの発明による磁気ヘッドの劣化判定方式におい
ては、検査ディスクの適当な個数のトラックに対するテ
ストの終了ごとに、基準ディスクが置き換えられ、その
1トラツクに対してテスト(;i’ シづのテスト(5
弓の平均読み出し電圧が逐次比較される。これが一定の
小さい比率で低下するときは使用頻度による磁気ヘッド
のI’l−能低下と判定し、また大きい比率で急激に低
下したときは磁気ヘッドが劣化したものと判定する。基
準ディスクは標準的な記録性能を有するので、磁気ヘッ
ドは常にIFシい判定)λ準により劣化が的確に判定さ
れるとともに、置き換えのサイクルを適切に設定するこ
とにより、検査中に発生した磁気ヘッドの劣化が速やか
に検出され、直ちに検りを中11−シて磁気ヘッドを交
換することができるので、I11検杏のロスが最小限に
とどめられる。
[Operation] In the magnetic head deterioration determination method according to the present invention described above, each time a test is completed on an appropriate number of tracks on the test disk, the reference disk is replaced, and the test (;i' Shizuno test (5
The average readout voltage of the bow is successively compared. When this decreases at a small constant rate, it is determined that the I'l-performance of the magnetic head has deteriorated due to the frequency of use, and when it rapidly decreases at a large rate, it is determined that the magnetic head has deteriorated. Since the reference disk has standard recording performance, the magnetic head is always tested for deterioration using the IF standard (λ standard), and by setting the replacement cycle appropriately, Since deterioration of the head is quickly detected and the magnetic head can be replaced immediately after inspection, the loss of I11 inspection can be minimized.

[実施例コ 第1図はこの発明による磁気ヘッドの劣化判定方式の原
理を示す回線図である。被検査ディスクのS個のトラッ
クに対するテストが終了するごとに基準ディスクが置き
換えられ、その置き換え番号1.2.3・・・・・・に
対する平均読み出し電Jfv(1)T V (2) +
 v (3)・・・・・・が逐次算出されてメモリに記
憶される。電圧Vの低下の比率をkとすると、kは−・
般に、[v (n−1)−v (n)]/ v (n−
1))により求められる。図においては、番号1,2.
3に対する比率には−一定の小数Kに等しいか、または
より小さく、使用頻度により磁気ヘッドの性能が漸次低
下したものとする。これに対しては、別途マイクロプロ
センサにrめ設定された補正係数により補11:、され
る。ここでは補11:、方法の説明を着略する。
[Example 1] FIG. 1 is a circuit diagram showing the principle of a magnetic head deterioration determination method according to the present invention. Each time the test on S tracks of the disk under test is completed, the reference disk is replaced, and the average read voltage Jfv (1) T V (2) + for the replacement number 1.2.3...
v (3)... are sequentially calculated and stored in the memory. If the rate of decrease in voltage V is k, then k is -・
In general, [v (n-1)-v (n)]/v (n-
1)). In the figure, numbers 1, 2.
It is assumed that the ratio to 3 is equal to or smaller than a certain decimal number K, and that the performance of the magnetic head gradually deteriorates depending on the frequency of use. This is compensated for by a correction coefficient that is separately set to the microprocessor sensor. Here, supplement 11: The explanation of the method will be omitted.

次に、l!’I /I<のようにv (m)が急激に低
下したときは、v(m−1)に対する比率kかKより人
きいので磁気ヘッドが劣化したものと判定し、良品の磁
気ヘッドに交換してテストが再開される。
Next, l! When v(m) suddenly decreases as shown in 'I/I<, the ratio k to v(m-1) is higher than K, so it is determined that the magnetic head has deteriorated, and the magnetic head is replaced with a good one. It will be replaced and the test will be restarted.

以トにおいて、)J(Qディスクの置き換えのサイクル
は知いはと劣化が速やかに検出されるが、反面、置き換
えとテスト信号の書き込み/読み出しなとに時間かかか
って検査効率が低下するので、磁気ヘッドの性能の低下
、または劣化の実情に合わせて適当なトラック数Sを選
定する。また、小定数には数Sに関係するが、夫績デー
タにより例えば1〜2%とする。なお、士、記の基準デ
ィスクに対するテスト信号の許き込み/読み出し、およ
び・II4均読6出し化バーの算出なとは、検査ディス
クに列する場合と同様に、第3図(C)、(d)の検聞
部3とマイクロプロセッサ4により1J゛われる。
In the following, the cycle of replacing the )J(Q disk) allows for rapid detection of deterioration, but on the other hand, it takes time to replace and write/read test signals, reducing inspection efficiency. , select an appropriate number of tracks S according to the actual situation of performance decline or deterioration of the magnetic head.Furthermore, the small constant is related to the number S, but is set to, for example, 1 to 2% depending on performance data. The acceptance/reading of the test signal for the standard disc described in , and the calculation of the ・II4 uniform readout bar are performed in the same manner as in the case of arraying on the test disc, as shown in FIG. The processing time is 1J by the inquest section 3 and microprocessor 4 in d).

第2図はこの発明による磁気ヘッドの劣化判定方式の実
施例におけるフローチャートを示す。サーテイファイヤ
に対して、基準ディスクが置き換えて装着され■、磁気
ヘッドによりその適当なlトラックに対してテスト信号
の書き込み/読み出しを行い、マイクロプロセッサによ
り・V6読み出し電圧v(n)  (最初はn=1とす
る)を算出する■。ついで削口の平均読み出し電EEv
(n−1)をメモリより読み出して■、比”*(k =
 [v (n−1)−v (n)]/ v (n−1)
が計算されて■、 定の小数にと比較され■、kがKよ
り小さいかまたは等しいときは使用頻度による磁気ヘッ
ドの性能低下とされ、v (n)をメモリに記憶する■
。次に、被検査ディスクを装着して所定のテストを行い
■、所定のS個のトラックに対するテストが終了したか
合かを判定し■、終了したときはステップは■に戻って
再び基準ディスクが置き換えられ、以ド同様の処理が繰
り返される。■の比較において、比埠くkがKより人き
いときは、磁気ヘッドが劣化したものとして良品の磁気
ヘッドに交換され、■に反って1〇− 1〕1ノ記と同様な処即がなされる。
FIG. 2 shows a flowchart in an embodiment of a method for determining deterioration of a magnetic head according to the present invention. A reference disk is installed in place of the certifier, and the magnetic head writes/reads test signals to/from appropriate tracks, and the microprocessor reads the V6 read voltage v(n) (initially n = 1)). Next, the average readout voltage EEv of the kuguchi
(n-1) is read from the memory and the ratio ”*(k =
[v (n-1)-v (n)]/v (n-1)
is calculated and compared to a constant decimal number. If k is less than or equal to K, it is assumed that the performance of the magnetic head has deteriorated due to the frequency of use, and v (n) is stored in memory.
. Next, the disk to be inspected is installed and a predetermined test is performed.■ It is determined whether the test for the predetermined S number of tracks has been completed.When the test is completed, the step returns to ■ and the reference disk is checked again. It is replaced and the same process is repeated. In the comparison of (■), if k is higher than K, the magnetic head is assumed to be deteriorated and replaced with a good magnetic head, and contrary to (■), the same treatment as in 10-1] No. 1 It will be done.

[発明の効果コ 以上の説明により明らかなように、この発明による磁気
ヘッドの劣化判定方式においては、判定)、(〜(とじ
て標専゛的な、1己録tI:能をイfするJ、Lηミ磁
気ディスクが、被検間の磁気ディスクの検量中に適当な
サイクルで磁気ディスクサーテイファイヤに置き換えて
装着され、その1トラツクに対するナス14,1号の・
1く均読み出し電1.1・が逐次比較され、この比二令
(を 定の小数に比較して、td、lxcヘッドの1/
1゛能低下と劣化がそれぞれ的確、かつ速やかに判定さ
れるもので、検在中に磁気ヘッドの劣化が判定されたと
きは、直ちにMAを中11・して磁気ヘッドを真品に交
換することにより、再検査のロスが最小限にとどめられ
、磁気ディスクサーテイファイヤのイ17頼性の同1.
と稼働効率の低下の防+lに寄′jする効果には大きい
ものがある。
[Effects of the Invention] As is clear from the above explanation, in the magnetic head deterioration determination method according to the present invention, A J, Lη magnetic disk is installed in place of a magnetic disk certifier at an appropriate cycle during calibration of the magnetic disk between tests, and the Nasu No. 14, 1 magnetic disk for one track is installed.
1 average readout voltage 1.1.
1. Performance loss and deterioration are determined accurately and quickly, and if deterioration of the magnetic head is determined during inspection, immediately perform MA 11 and replace the magnetic head with a genuine one. This minimizes the loss of re-inspection and improves the reliability of the magnetic disk certifier.
This has a significant effect on preventing a decline in operating efficiency.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は、この発明による磁気へノドの劣化判定方式の
判定原裡の説明間、第2図はこの発明による磁気ヘッド
の劣化判定方式の実施例におけるフローチャート、第3
図(a ) 、 (b ) 、 (c )および(d)
は、磁気ディスクサーテイファイヤの概餅とエラーテス
トシーケンスの説明間である。 1・・・被検査磁気ディスク(検査ディスク)、2・・
・磁気ヘッド部、   2a・・・磁気ヘッド、2b・
・・キャリッジ機構、3・・・検査部、3a・・・δき
込みアンプ、3b・・・読み出しアンプ、3c・・・書
き込み制御回路、3d・・・エラー検出回路、4・・・
マイクロプロセッサ、5・・・コントローラ、6・・・
トラックシーク機構、 ■〜■・・・フローチャートのステップ番号。
FIG. 1 is an explanation of the determination source of the magnetic head deterioration determination method according to the present invention, FIG. 2 is a flowchart of an embodiment of the magnetic head deterioration determination method according to the present invention, and FIG.
Figures (a), (b), (c) and (d)
This is a general description of the magnetic disk certifier and an explanation of the error test sequence. 1... Magnetic disk to be inspected (test disk), 2...
・Magnetic head part, 2a...Magnetic head, 2b・
... Carriage mechanism, 3... Inspection section, 3a... δ reading amplifier, 3b... Read amplifier, 3c... Write control circuit, 3d... Error detection circuit, 4...
Microprocessor, 5... Controller, 6...
Track seek mechanism, ■~■...Step number of flowchart.

Claims (1)

【特許請求の範囲】[Claims] (1)マイクロプロセッサの制御のもとに、磁気ヘッド
により被検査磁気ディスクのトラックに逐次テスト信号
の書き込み/読み出しを行い、該読み出しされたテスト
信号のエラーを検出して記録媒体を検査する磁気ディス
クサーティファイヤにおいて、上記被検査磁気ディスク
の適当な個数のトラックに対するテストの終了ごとに、
上記被検査の磁気ディスクに代わって、標準的な記録性
能を有する基準磁気ディスクを置き換えて判定基準とし
、該置き換えられた各基準磁気ディスクの1トラックに
対するテスト信号の平均読み出し電圧をそれぞれ算出し
て逐次比較し、該平均読み出し電圧が、一定の小さい比
率で低下するときは使用頻度による該磁気ヘッドの性能
低下と判定し、大きい比率で急激に低下したとき該磁気
ヘッドが劣化したと判定することを特徴とする、磁気ヘ
ッドの劣化判定方式。
(1) Under the control of a microprocessor, a magnetic head sequentially writes/reads test signals to/from the tracks of a magnetic disk to be inspected, detects errors in the read test signals, and inspects the recording medium. In the disk certifier, each time a test is completed on an appropriate number of tracks on the magnetic disk to be inspected,
In place of the magnetic disk to be inspected, a reference magnetic disk having standard recording performance is used as a judgment standard, and the average read voltage of the test signal for one track of each replaced reference magnetic disk is calculated. When the average read voltage decreases at a small constant rate by successive comparison, it is determined that the performance of the magnetic head has deteriorated due to the frequency of use, and when the average read voltage decreases rapidly at a large rate, it is determined that the magnetic head has deteriorated. A magnetic head deterioration determination method characterized by:
JP2053999A 1990-03-06 1990-03-06 Deterioration determination method for magnetic head Expired - Lifetime JP2529891B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2053999A JP2529891B2 (en) 1990-03-06 1990-03-06 Deterioration determination method for magnetic head

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2053999A JP2529891B2 (en) 1990-03-06 1990-03-06 Deterioration determination method for magnetic head

Publications (2)

Publication Number Publication Date
JPH03256211A true JPH03256211A (en) 1991-11-14
JP2529891B2 JP2529891B2 (en) 1996-09-04

Family

ID=12958305

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2053999A Expired - Lifetime JP2529891B2 (en) 1990-03-06 1990-03-06 Deterioration determination method for magnetic head

Country Status (1)

Country Link
JP (1) JP2529891B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998001104A1 (en) * 1996-07-08 1998-01-15 Daikin Industries, Ltd. Cosmetic preparations containing fluorinated oils
KR100640627B1 (en) * 2005-01-06 2006-10-31 삼성전자주식회사 Method for tuning a MR head skew of HDD using CSM test
US7288935B2 (en) 2005-04-15 2007-10-30 Hitachi Global Storage Technologies Netherlands Bv System, method, and apparatus for dynamic electrical testing of workpieces by multiplexing test sites with shared electronics

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998001104A1 (en) * 1996-07-08 1998-01-15 Daikin Industries, Ltd. Cosmetic preparations containing fluorinated oils
US6136331A (en) * 1996-07-08 2000-10-24 Daikin Industries Ltd Cosmetic preparations containing fluorinated oils
KR100640627B1 (en) * 2005-01-06 2006-10-31 삼성전자주식회사 Method for tuning a MR head skew of HDD using CSM test
US7288935B2 (en) 2005-04-15 2007-10-30 Hitachi Global Storage Technologies Netherlands Bv System, method, and apparatus for dynamic electrical testing of workpieces by multiplexing test sites with shared electronics

Also Published As

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