JPS62204619A - Output signal stabilizing method for magnetic encoder - Google Patents
Output signal stabilizing method for magnetic encoderInfo
- Publication number
- JPS62204619A JPS62204619A JP61047761A JP4776186A JPS62204619A JP S62204619 A JPS62204619 A JP S62204619A JP 61047761 A JP61047761 A JP 61047761A JP 4776186 A JP4776186 A JP 4776186A JP S62204619 A JPS62204619 A JP S62204619A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic recording
- recording medium
- gap
- magnetoresistive element
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims description 6
- 230000000087 stabilizing effect Effects 0.000 title claims description 6
- 238000001514 detection method Methods 0.000 claims description 8
- 230000000737 periodic effect Effects 0.000 claims description 4
- 230000003068 static effect Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
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- Analogue/Digital Conversion (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は、磁気記録媒体から所定距離離れた位置に、
磁気記録媒体から受ける磁界の周期的変化に応じて抵抗
値が変化する磁気抵抗素子を備え、この磁気抵抗素子の
抵抗値変化に基づいて検出信号を出力する磁気エンコー
ダーにおいて、その出力信号を安定化させろための出力
信号安定化方法１こ関ずろ乙のである。[Detailed Description of the Invention] [Industrial Application Field] This invention provides a magnetic recording medium at a position a predetermined distance away from the magnetic recording medium.
Stabilizes the output signal in a magnetic encoder that is equipped with a magnetoresistive element whose resistance value changes according to periodic changes in the magnetic field received from a magnetic recording medium, and outputs a detection signal based on the change in the resistance value of this magnetoresistive element. This is the first method for stabilizing the output signal.
［従来の技術］
この種の磁気エンコーダーとしては、回転する磁気記録
媒体と対向する定位置に磁気抵抗素子を備えて、磁気記
録媒体の回転に伴って、磁気記録媒体に形成された所定
の着磁パターンの磁気スケールから、磁気抵抗素子に対
して周期的に変化す磁界を与えるように構成されたもの
が知られている。磁気抵抗素子は、磁界の周期的な変化
に応じてその抵抗値を変化させ、その抵抗値の変化に基
づいて検出信号を出力する。[Prior Art] This type of magnetic encoder is equipped with a magnetoresistive element at a fixed position facing a rotating magnetic recording medium, and as the magnetic recording medium rotates, a predetermined attachment formed on the magnetic recording medium is attached. A device is known that is configured to apply a periodically changing magnetic field to a magnetoresistive element based on a magnetic scale of a magnetic pattern. The magnetoresistive element changes its resistance value in response to periodic changes in the magnetic field, and outputs a detection signal based on the change in resistance value.
従来、このような磁気エンコーダーにあっては、磁気記
録媒体から所定距離離れた位置に、磁気抵抗素子が固定
的に備えられていた。そして、その固定的に備えた磁気
抵抗素子の抵抗１直変化に基づいて、検出信号が出力さ
れていた。Conventionally, in such a magnetic encoder, a magnetoresistive element has been fixedly provided at a position a predetermined distance away from a magnetic recording medium. Then, a detection signal is output based on a one-direction change in resistance of the fixedly provided magnetoresistive element.
［発明が解決しようとする問題点］
従来は、固定的に備えた磁気抵抗素子の抵抗値変化に基
づいて検出信号を出力しているため、次のような問題が
あった。[Problems to be Solved by the Invention] Conventionally, since a detection signal is output based on a change in the resistance value of a fixedly provided magnetoresistive element, the following problems have occurred.
すなわち、磁気記録媒体の反りなどによる磁気記録媒体
自体の位置変動によって、その磁気記録媒体と磁気抵抗
素子との間のギャップが変動し、その変動のために、磁
気抵抗素子が磁気記録媒体から受ける磁界の強さが大き
く変化して、出力信号に大きな振幅変動、波形歪が生じ
ていた。しかも、その波形歪の発生は精度を落とす原因
となり、高分解能化を図る上においての問題となってい
た。In other words, the gap between the magnetic recording medium and the magnetoresistive element changes due to positional fluctuations in the magnetic recording medium itself due to warping of the magnetic recording medium, and due to this fluctuation, the magnetoresistive element receives less force from the magnetic recording medium. The strength of the magnetic field changed significantly, causing large amplitude fluctuations and waveform distortion in the output signal. Moreover, the generation of waveform distortion causes a drop in accuracy, which poses a problem in achieving high resolution.
この発明は、このような問題を解決して、出力信号を安
定化させることを目的としている。The present invention aims to solve such problems and stabilize the output signal.
［問題点を解決するための手段］
この発明の磁気エンコーダーの出力信号安定化方法は、
磁気記録体から所定圧Ｍ離れた位置に、磁気記録媒体か
ら受ける磁界の周期的変化に応じて抵抗値が変化する磁
気抵抗素子を備え、この磁気抵抗素子の抵抗値変化に基
づいて検出信号を出力する磁気エンコーダーにおいて、
前記磁気記録媒体と前記磁気抵抗素子との間のギャップ
を検出し、
そのギャップの検出信号に基いて、前記磁気記録媒体と
磁気抵抗素子との間のギャップを一定に保つように前記
磁気抵抗素子の位置を前記磁気記録媒体との対向方向に
沿って調整することを特徴としている。[Means for solving the problem] The method for stabilizing the output signal of a magnetic encoder according to the present invention is as follows:
A magnetoresistive element whose resistance value changes according to periodic changes in the magnetic field received from the magnetic recording medium is provided at a position a predetermined pressure M away from the magnetic recording medium, and a detection signal is generated based on the resistance value change of this magnetoresistive element. A magnetic encoder that outputs detects a gap between the magnetic recording medium and the magnetoresistive element, and maintains a constant gap between the magnetic recording medium and the magnetoresistive element based on a detection signal of the gap. The magnetic recording medium is characterized in that the position of the magnetoresistive element is adjusted along the direction facing the magnetic recording medium.
［作用］
この発明の磁気エンコーダーの出力信号安定化方法は、
磁気記録媒体と磁気抵抗素子との間のギャップの変動に
応じて磁気抵抗素子の位置を調整ずろことにより、磁気
記録媒体と磁気抵抗素子との間のギャップを常に一定に
保って、磁気記録媒体から磁気抵抗素子への磁界の強さ
が磁気記録媒体の位置変動によって変化することを未然
に回避する。[Function] The method for stabilizing the output signal of a magnetic encoder of the present invention is as follows:
By adjusting the position of the magnetoresistive element according to changes in the gap between the magnetic recording medium and the magnetoresistive element, the gap between the magnetic recording medium and the magnetoresistive element is always kept constant, and the magnetic recording medium This prevents the strength of the magnetic field from changing to the magnetoresistive element from changing due to positional fluctuations of the magnetic recording medium.
［実施例］
以下、この発明の一実施例を第１図に基づいて説明する
。[Example] Hereinafter, an example of the present invention will be described based on FIG. 1.
本実施例はロータリーエンコーダーへの適応例であり、
図中１は検出対象となる磁気記録円板（磁気記録媒体）
である。磁気記録円板１はシャフト２に取り付けられて
いて、そのシャフト２と共に図中の上下方向の軸線を中
心として回転する。この磁気記録円板ｌの下面には、そ
の周方向に沿って所定の着磁パターンの磁気スケールが
形成されている。一方、磁気記録円板ｌの磁気スケール
との対向する位置には磁気抵抗素子３が備えられている
。この磁気抵抗素子３は、磁気記録円板ｌの回転に伴っ
てその磁気スケールから周期的に変化する磁界を受け、
その磁界の変化に応じて抵抗値を変化させる。This example is an example of application to a rotary encoder.
1 in the figure is the magnetic recording disk (magnetic recording medium) to be detected.
It is. The magnetic recording disk 1 is attached to a shaft 2, and rotates together with the shaft 2 about an axis in the vertical direction in the figure. A magnetic scale with a predetermined magnetization pattern is formed on the lower surface of the magnetic recording disk l along its circumferential direction. On the other hand, a magnetoresistive element 3 is provided on the magnetic recording disk l at a position facing the magnetic scale. This magnetoresistive element 3 receives a magnetic field that changes periodically from its magnetic scale as the magnetic recording disk l rotates.
The resistance value changes according to changes in the magnetic field.
本例の場合、磁気抵抗素子３は圧電素子４を介して定位
置に備えられており、その圧電素子４は、コントロール
回路５からの印加電圧に応じて磁気抵抗素子３を磁気記
録円板ｌとの対向方向、つまり図中の上下方向に変位さ
せる。圧電素子４は、例えば１０層の積層構造のもので
ある。コントロール回路５には、磁気記録円板！の上面
と所定の間隔を隔てて対向する固定電極６と、シャフト
２に接続された電極７が接続されており、コントロール
回路５は、これら両電極６．７間の静電容量を検出し、
その検出値に基づいて圧電素子４への印加電圧をコント
ロールする。In the case of this example, the magnetoresistive element 3 is provided at a fixed position via a piezoelectric element 4, and the piezoelectric element 4 moves the magnetoresistive element 3 to the magnetic recording disk in accordance with the applied voltage from the control circuit 5. , that is, in the vertical direction in the figure. The piezoelectric element 4 has a laminated structure of, for example, 10 layers. The control circuit 5 has a magnetic recording disk! A fixed electrode 6 facing the upper surface at a predetermined distance and an electrode 7 connected to the shaft 2 are connected, and the control circuit 5 detects the capacitance between these two electrodes 6 and 7.
The voltage applied to the piezoelectric element 4 is controlled based on the detected value.
電極６．７間の静電容量は、磁気記録円板ｌの」二面と
固定電極６との間のギャップの変動に応じて変化する。The capacitance between the electrodes 6 , 7 changes depending on the variation of the gap between the two sides of the magnetic recording disk l and the fixed electrode 6 .
このギャップの変動は、磁気記録円板ｌの下面と磁気抵
抗素子３との間のギャップの変動でもある。したがって
、コントロール回路５は、両電極６．７間の静電容量の
変化によって磁気記録円板ｌと磁気抵抗素子３との間の
ギャップを検出することになる。そして、コントロール
回路５は、その磁気記録円板ｌと磁気抵抗素子３との間
のギャップを常に一定に保つように、圧電素子４への印
加電圧を自動的にコントロールして、磁気抵抗素子３の
位置を調整する。このようにして、磁気記録円板１の下
面と磁気抵抗素子３との間のギャップを２〜５μｍの値
に保つ。This variation in the gap is also a variation in the gap between the lower surface of the magnetic recording disk l and the magnetoresistive element 3. Therefore, the control circuit 5 detects the gap between the magnetic recording disk l and the magnetoresistive element 3 based on the change in the capacitance between the electrodes 6.7. Then, the control circuit 5 automatically controls the voltage applied to the piezoelectric element 4 so as to keep the gap between the magnetic recording disk l and the magnetoresistive element 3 constant. Adjust the position. In this way, the gap between the lower surface of the magnetic recording disk 1 and the magnetoresistive element 3 is maintained at a value of 2 to 5 μm.
この結果、磁気抵抗素子３を固定的に備えた従来の場合
に最大波形歪１３％、最大振幅変動２０％であった出力
信号が、最大波形歪４％、最大振幅変動３％となって安
定化した。As a result, the output signal, which had a maximum waveform distortion of 13% and a maximum amplitude fluctuation of 20% in the conventional case with a fixed magnetoresistive element 3, became stable with a maximum waveform distortion of 4% and a maximum amplitude fluctuation of 3%. It became.
［発明の効果］
以上説明したように、この発明の磁気エンコーダーの出
力信号安定化方法は、磁気記録媒体と磁気抵抗素子との
間のギャップの変動に応じて磁気抵抗素子の位置を調整
することにより、磁気記録媒体と磁気抵抗素子との間の
ギャップを常に一定に保つから、磁気記録媒体から磁気
抵抗素子への磁界の強さが磁気記録媒体の位置変動によ
って変化することを未然に回避することができ、この結
果、出力信号の波形歪、振幅変動を抑えてそれを安定化
さＵ、高性能化、高分解能化を実現することができる。[Effects of the Invention] As explained above, the method for stabilizing the output signal of a magnetic encoder according to the present invention adjusts the position of the magnetoresistive element according to the variation in the gap between the magnetic recording medium and the magnetoresistive element. This keeps the gap between the magnetic recording medium and the magnetoresistive element constant, thereby preventing the strength of the magnetic field from the magnetic recording medium to the magnetoresistive element from changing due to positional changes in the magnetic recording medium. As a result, waveform distortion and amplitude fluctuations of the output signal can be suppressed and stabilized, and higher performance and resolution can be achieved.
第１図はこの発明の一実施例を説明するための使用装置
の概略構成図である。
１・・・・・磁気記録円板（磁気記録媒体）、２・・・
・・シャフト、 ３・・・・・磁気抵抗素子、４・・
・・・・圧電素子、 ５・・・・・コントロール回路
、６．７・・・・・電極。FIG. 1 is a schematic diagram of an apparatus used for explaining an embodiment of the present invention. 1...Magnetic recording disk (magnetic recording medium), 2...
...Shaft, 3...Magnetic resistance element, 4...
... Piezoelectric element, 5 ... Control circuit, 6.7 ... Electrode.
Claims (1)
から受ける磁界の周期的変化に応じて抵抗値が変化する
磁気抵抗素子を備え、この磁気抵抗素子の抵抗値変化に
基づいて検出信号を出力する磁気エンコーダーにおいて
、 前記磁気記録媒体と前記磁気抵抗素子との間のギャップ
を検出し、 そのギャップの検出信号に基いて、前記磁気記録媒体と
磁気抵抗素子との間のギャップを一定に保つように前記
磁気抵抗素子の位置を前記磁気記録媒体との対向方向に
沿って調整することを特徴とする磁気エンコーダーの出
力信号安定化方法。[Claims] A magnetoresistive element whose resistance value changes in response to periodic changes in the magnetic field received from the magnetic recording medium is provided at a position a predetermined distance from the magnetic recording medium, A magnetic encoder that outputs a detection signal based on the magnetic recording medium and the magnetoresistive element detects a gap between the magnetic recording medium and the magnetoresistive element, and detects a gap between the magnetic recording medium and the magnetoresistive element based on the detection signal of the gap. A method for stabilizing an output signal of a magnetic encoder, comprising adjusting the position of the magnetoresistive element along a direction facing the magnetic recording medium so as to keep a constant gap.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61047761A JPS62204619A (en) | 1986-03-05 | 1986-03-05 | Output signal stabilizing method for magnetic encoder |
| DE8686810603T DE3686330T2 (en) | 1985-12-28 | 1986-12-18 | CONTACTLESS MARKING SENSOR. |
| EP86810603A EP0242492B1 (en) | 1985-12-28 | 1986-12-18 | An improved non-contact type pattern sensor |
| KR1019860011227A KR910006670B1 (en) | 1985-12-28 | 1986-12-24 | Untouching type pattern sensor improved |
| US07/271,388 US4944028A (en) | 1985-12-28 | 1988-11-10 | Non-contact type pattern sensor with variable clearance compensation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61047761A JPS62204619A (en) | 1986-03-05 | 1986-03-05 | Output signal stabilizing method for magnetic encoder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62204619A true JPS62204619A (en) | 1987-09-09 |
Family
ID=12784352
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61047761A Pending JPS62204619A (en) | 1985-12-28 | 1986-03-05 | Output signal stabilizing method for magnetic encoder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62204619A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02201116A (en) * | 1989-01-30 | 1990-08-09 | Okuma Mach Works Ltd | Rotation angle detector |
| JP2013200235A (en) * | 2012-03-26 | 2013-10-03 | Mitsubishi Electric Corp | Read head control mechanism and optical encoder |
-
1986
- 1986-03-05 JP JP61047761A patent/JPS62204619A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02201116A (en) * | 1989-01-30 | 1990-08-09 | Okuma Mach Works Ltd | Rotation angle detector |
| JP2013200235A (en) * | 2012-03-26 | 2013-10-03 | Mitsubishi Electric Corp | Read head control mechanism and optical encoder |
| EP2645068A3 (en) * | 2012-03-26 | 2017-01-18 | Mitsubishi Electric Corporation | Readhead control mechanism and optical encoder |
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