JPS5858407A - Detecting circuit for projection of magnetic disc - Google Patents
Detecting circuit for projection of magnetic discInfo
- Publication number
- JPS5858407A JPS5858407A JP15627181A JP15627181A JPS5858407A JP S5858407 A JPS5858407 A JP S5858407A JP 15627181 A JP15627181 A JP 15627181A JP 15627181 A JP15627181 A JP 15627181A JP S5858407 A JPS5858407 A JP S5858407A
- Authority
- JP
- Japan
- Prior art keywords
- floating head
- projections
- changing
- magnetic disc
- floating
- 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.)
- Pending
Links
Landscapes
- Length Measuring Devices Characterised By Use Of Acoustic Means (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は浮動ヘッドと回転する磁気ディスク上の突起と
の衝突により発生する弾性波により突起の数と大きさを
検出する磁気ディスクの突起検出回路に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a protrusion detection circuit for a magnetic disk that detects the number and size of protrusions using elastic waves generated by a collision between a floating head and a protrusion on a rotating magnetic disk.
従来は浮動ヘッドの浮上高さの突起の有無しか判別でき
ず、高さの異なる突起の数を知るには浮動ヘッドの浮上
量を変える必要があシ、浮上量を変えるには浮動ヘッド
を変えるか又は磁気ディスクの回転数を変えるという手
間がかかりた・
本発明の目的は浮動ヘッド又は磁気ディスクの回転数を
変えることなしに、振幅弁別器のしきい値のみを変える
ことにより1.突起の高さ別の頻度分布を得ることにあ
る。Previously, it was only possible to determine the presence or absence of protrusions at the flying height of the floating head; to determine the number of protrusions of different heights, it was necessary to change the flying height of the floating head; to change the flying height, change the floating head. 1. The purpose of the present invention is to change only the threshold value of the amplitude discriminator without changing the rotation speed of the floating head or the magnetic disk. The objective is to obtain the frequency distribution according to the height of the protrusions.
本発明の磁気ディスクの突起検出回路は、浮動へ゛ラド
と回転する磁気ディスク上の突起との衝突によシ発生す
る弾性波を検出する検出素子を浮動ヘッドに設け、この
検出素子からの出力を振幅弁別器に入力し、設定しきい
値との゛比較。The protrusion detection circuit for a magnetic disk of the present invention includes a floating head equipped with a detection element that detects an elastic wave generated by a collision between a floating helad and a protrusion on a rotating magnetic disk, and an output from this detection element. Input to amplitude discriminator and compare with set threshold.
により突起の数と大きさを検出することを*Wとするも
のである。The number and size of protrusions are detected by *W.
第1図は本発明の原理説明図である。浮動ヘッド1と回
転する磁気ディスク2上の突起3〜6との衝突によシ発
生する検出素子信号波形は第1図(b)のようになる。FIG. 1 is a diagram explaining the principle of the present invention. The detection element signal waveform generated by the collision between the floating head 1 and the protrusions 3 to 6 on the rotating magnetic disk 2 is as shown in FIG. 1(b).
この信号のピーク値は浮動ヘッド1の浮上量と突起3〜
6の高さに応じて変化したものが得られる。この浮上量
と突起為さによる検出信号のピーク値は予めデータとし
て用意しておき、それに基づき第1図Φ)の人、B10
のようにしきい値を設定する。それぞれのしきい値を越
えた検出信号に対して第1図(C)(d) (e)のよ
うにパルス成形を行ない、このパルスをカウントする。The peak value of this signal is the flying height of the floating head 1 and the protrusion 3~
6 can be obtained depending on the height. The peak value of the detection signal based on the flying height and protrusion is prepared in advance as data, and based on this data, the person Φ) in Figure 1, B10
Set the threshold as follows. The detection signals exceeding the respective thresholds are subjected to pulse shaping as shown in FIGS. 1(C), (d), and (e), and the pulses are counted.
これにより突起の大き′さと数を知ることができる。This allows us to know the size and number of protrusions.
(C)はしきい傭人を越えたもの(浮上量6以上)が1
個、(d)はしきい値Bを越えたもの(浮上量β〜a)
が2個、(e)はしきい値Cを越えたもの(浮上量β〜
a)が4個あった場合を示している。(C) Those exceeding the threshold (surfacing height 6 or more) are 1
(d) exceeds the threshold B (flying height β ~ a)
(e) exceeds the threshold value C (flying height β ~
The case where there are four a) is shown.
この発明により浮動ヘッド又は磁気ディスクの回転数を
変えることなしに、振幅弁別器のしきい値のみを変える
ことにより、突起の高さ別の制度分布を得ることができ
、る。According to the present invention, by changing only the threshold value of the amplitude discriminator without changing the number of rotations of the floating head or magnetic disk, it is possible to obtain a precision distribution according to the height of the protrusion.
第1図は本発明の原理説明図であり、(a)は浮動ヘッ
ドと磁気ディスク突起を示す図、Φ)線検出信号波形と
しきい植を示す図、(C) (d) (@)はしきい値
を越えた信号に対して成形されたパルスを示す図である
。
A、8%0・・・・・・・・・しきい値1・・・・・・
浮動ヘッド 2・・・・・・磁気ディスクS〜6・・
・・・・突起FIG. 1 is a diagram explaining the principle of the present invention, (a) is a diagram showing a floating head and a magnetic disk protrusion, (C) (d) (@) is a diagram showing a Φ) line detection signal waveform and a threshold. FIG. 3 shows a pulse shaped for a signal that exceeds a threshold; A, 8%0...Threshold 1...
Floating head 2...Magnetic disk S~6...
····protrusion
Claims (1)
より発生する弾性波を検出する検出素子を浮動ヘッドに
設け、この検出素子からの出力を振幅弁別器に入力し、
突起の大きさに対応した設定しきい値との比較により突
起の数と大きさを検出することを特徴とする磁気ディス
クの突起検出回路・A detection element is provided on the floating head to detect an elastic wave generated by a collision between the floating head and a protrusion on a rotating magnetic disk, and the output from this detection element is input to an amplitude discriminator.
A protrusion detection circuit for a magnetic disk, which detects the number and size of protrusions by comparing them with a set threshold value corresponding to the size of the protrusions.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP15627181A JPS5858407A (en) | 1981-10-02 | 1981-10-02 | Detecting circuit for projection of magnetic disc |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP15627181A JPS5858407A (en) | 1981-10-02 | 1981-10-02 | Detecting circuit for projection of magnetic disc |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5858407A true JPS5858407A (en) | 1983-04-07 |
Family
ID=15624158
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP15627181A Pending JPS5858407A (en) | 1981-10-02 | 1981-10-02 | Detecting circuit for projection of magnetic disc |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5858407A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61151456A (en) * | 1984-12-25 | 1986-07-10 | Fujitsu Ltd | Method for testing magnetic disk medium |
JPH03230320A (en) * | 1990-02-05 | 1991-10-14 | Fuji Electric Co Ltd | Method for removing projection on disk surface of disk memory device |
-
1981
- 1981-10-02 JP JP15627181A patent/JPS5858407A/en active Pending
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61151456A (en) * | 1984-12-25 | 1986-07-10 | Fujitsu Ltd | Method for testing magnetic disk medium |
JPH0240971B2 (en) * | 1984-12-25 | 1990-09-14 | Fujitsu Ltd | |
JPH03230320A (en) * | 1990-02-05 | 1991-10-14 | Fuji Electric Co Ltd | Method for removing projection on disk surface of disk memory device |
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