JP3523797B2 - Magnetic encoder - Google Patents
Magnetic encoderInfo
- Publication number
- JP3523797B2 JP3523797B2 JP01533999A JP1533999A JP3523797B2 JP 3523797 B2 JP3523797 B2 JP 3523797B2 JP 01533999 A JP01533999 A JP 01533999A JP 1533999 A JP1533999 A JP 1533999A JP 3523797 B2 JP3523797 B2 JP 3523797B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- thin film
- giant magnetoresistive
- dispersed
- magnetoresistive material
- 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 - Fee Related
Links
- 230000005291 magnetic effect Effects 0.000 title claims description 160
- 239000010409 thin film Substances 0.000 claims description 55
- 239000000463 material Substances 0.000 claims description 47
- 238000001514 detection method Methods 0.000 claims description 30
- 239000000758 substrate Substances 0.000 claims description 16
- 239000006249 magnetic particle Substances 0.000 claims description 15
- 239000010408 film Substances 0.000 claims description 10
- 229910052802 copper Inorganic materials 0.000 claims description 7
- 239000011159 matrix material Substances 0.000 claims description 6
- 229910052737 gold Inorganic materials 0.000 claims description 4
- 229910052697 platinum Inorganic materials 0.000 claims description 4
- 229910052709 silver Inorganic materials 0.000 claims description 4
- 230000000694 effects Effects 0.000 description 15
- 239000010949 copper Substances 0.000 description 9
- 230000035945 sensitivity Effects 0.000 description 7
- 229910052742 iron Inorganic materials 0.000 description 5
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 230000003287 optical effect Effects 0.000 description 4
- 239000000428 dust Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 229910052759 nickel Inorganic materials 0.000 description 3
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910052703 rhodium Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910019230 CoFeSiB Inorganic materials 0.000 description 1
- 229910000976 Electrical steel Inorganic materials 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910000808 amorphous metal alloy Inorganic materials 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000005292 diamagnetic effect Effects 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 239000003302 ferromagnetic material Substances 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 229910001172 neodymium magnet Inorganic materials 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 230000005298 paramagnetic effect Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 229910000889 permalloy Inorganic materials 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
- 229910000938 samarium–cobalt magnet Inorganic materials 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000005469 synchrotron radiation Effects 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
Landscapes
- Hall/Mr Elements (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
- Measuring Magnetic Variables (AREA)
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、磁気式エンコーダ
に関し、さらに詳しくは、基板上に磁性粒子分散型巨大
磁気抵抗材料の薄膜を形成した磁気検出素子を用いるこ
とによって、小型かつ高感度、高出力、高分解能を有す
る磁気式エンコーダに関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic encoder, and more particularly to a magnetic encoder, in which a thin film of a magnetic particle-dispersed giant magnetoresistive material is formed on a substrate, whereby a small size and high sensitivity and The present invention relates to a magnetic encoder having an output and high resolution.
【０００２】[0002]
【従来の技術】従来のエンコーダは、磁気式と光学式に
大別される。従来、磁気式エンコーダでは、位置信号と
して等間隔に着磁された複数の磁極を有する磁気記録媒
体の移動に伴って周期的に現れる磁気パターンの検出素
子として、磁気抵抗効果センサ（特開昭５９−１４７２
１３号、特開平２−１９５２８４号、特開平７−１３９
９６６号）やホールセンサなどの磁気センサが用いられ
ており、また、磁気抵抗効果素子としては例えばＮｉＦ
ｅ合金（特開平２−１９５２８４号）などが用いられて
いる。2. Description of the Related Art Conventional encoders are roughly classified into magnetic type and optical type. Conventionally, in a magnetic encoder, a magnetoresistive effect sensor (Japanese Patent Laid-Open No. Sho 59-59) is used as a detection element for a magnetic pattern which appears periodically with the movement of a magnetic recording medium having a plurality of magnetic poles magnetized at equal intervals as position signals. -1472
No. 13, JP-A-2-195284, JP-A-7-139.
966), a Hall sensor, or other magnetic sensor is used, and the magnetoresistive element is, for example, NiF.
For example, an e-alloy (Japanese Patent Laid-Open No. 2-195284) is used.
【０００３】一方、光学式エンコーダでは、レーザー光
を光源とし、検出器として光センサを用いており、光源
と検出器の間に回折格子を設け、回折した光を回折格子
後方に設けた検出器によって観察し、回折光の強度変化
によって精密な位置を検出するものがある。On the other hand, in an optical encoder, a laser beam is used as a light source and an optical sensor is used as a detector. A diffraction grating is provided between the light source and the detector, and the diffracted light is provided behind the diffraction grating. There is a method in which a precise position is detected by observing the light and changing the intensity of the diffracted light.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、磁気検
出素子としてホールセンサを使用したエンコーダでは、
ホール素子が４端子構造を持つことから微細・小型化が
困難なため、μｍオーダーでの高分解能が得られないと
いう問題がある。また、半導体を使用しているため、高
周波の磁界変化に対して応答性が得られない、高温下で
使用できないといった問題がある。However, in the encoder using the Hall sensor as the magnetic detection element,
Since the Hall element has a four-terminal structure, it is difficult to miniaturize and miniaturize it, and there is a problem that high resolution in the μm order cannot be obtained. In addition, since a semiconductor is used, there are problems that it is not responsive to changes in high-frequency magnetic field and cannot be used at high temperatures.
【０００５】一方、磁気抵抗効果センサを用いたもので
は、小型化は可能であるが、数十Ｏｅ以上の高磁界に対
する応答性がなく、外部から磁界を印加された場合、測
定が困難となる問題がある。そのため、数百Ｏｅ以上の
高磁界を有するモータなどの回転センサとしての使用
や、鋼材の側での使用など、高磁界の影響を受けるよう
な環境で使用する場合、磁気シールドが必要となり、装
置が大きくなるという問題がある。On the other hand, a device using a magnetoresistive effect sensor can be miniaturized, but has no responsiveness to a high magnetic field of several tens Oe or more, and measurement is difficult when a magnetic field is applied from the outside. There's a problem. Therefore, when used as a rotation sensor of a motor having a high magnetic field of several hundreds of Oe or more, or when used in an environment that is affected by a high magnetic field such as on the steel material side, a magnetic shield is required, and the device is There is a problem that becomes large.
【０００６】また、光学式エンコーダでは、μｍオーダ
ーでの高分解能は得られるものの、埃、オイルミストな
どの汚れが付着した時に検出感度が低下し、また高温、
放射光などの環境下では測定が困難になるといった問題
がある。さらに、検出にレーザー光源、回折格子といっ
た精密機器を用いており、装置自体が大きくかつ高価な
ものになるといった問題がある。In addition, although the optical encoder can obtain high resolution on the order of μm, its detection sensitivity decreases when dirt such as dust or oil mist adheres, and high temperature,
There is a problem that measurement becomes difficult in an environment such as synchrotron radiation. Further, since precision equipment such as a laser light source and a diffraction grating is used for detection, there is a problem that the apparatus itself becomes large and expensive.
【０００７】従って、本発明の目的は、磁気検出素子の
微細・小型化、高磁界中での磁気測定、高周波対応が可
能であり、また、温度変化による出力変化が小さく、し
かも汚れなどの影響を受けない高感度、高出力、高分解
能の安価な磁気式エンコーダを提供することにある。Therefore, an object of the present invention is to enable miniaturization and miniaturization of a magnetic detection element, magnetic measurement in a high magnetic field, high frequency compatibility, small output change due to temperature change, and influence of dirt and the like. It is to provide an inexpensive magnetic encoder with high sensitivity, high output, and high resolution that is not affected by the problem.
【０００８】[0008]
【課題を解決するための手段】前記目的を達成するため
に、本発明によれば、等間隔に着磁された複数の磁極を
有する磁気記録媒体と、該磁気記録媒体の磁気パターン
を検出する磁気検出素子を有する磁気検出器とを備え、
該磁気検出素子を上記磁気記録媒体の磁界が作用する範
囲内で相対移動自在に対向して配設してなる磁気式エン
コーダであって、上記磁気検出素子が、電気伝導性マト
リックス中に磁性粒子を分散させた構造を有する磁性粒
子分散型巨大磁気抵抗材料の薄膜を用いた巨大磁気抵抗
素子であって、基板上に直接又は絶縁層を介して形成さ
れた磁性粒子分散型巨大磁気抵抗材料の薄膜及びその一
方の端部に電気的に接続された第一の電極薄膜と、これ
ら磁性粒子分散型巨大磁気抵抗材料の薄膜及び第一の電
極薄膜の上部に絶縁層を介して形成され、かつ上記磁性
粒子分散型巨大磁気抵抗材料の薄膜の他方の端部に電気
的に接続された第二の電極薄膜とからなる積層膜、ある
いは、基板上に直接又は絶縁層を介して形成された上記
第二の電極薄膜と、該第二の電極薄膜の上部に絶縁層を
介して形成された上記磁性粒子分散型巨大磁気抵抗材料
の薄膜及び第一の電極薄膜とからなる積層膜であること
を特徴とする磁気式エンコーダが提供される。好適な態
様によれば、上記磁気検出器は、上記磁気検出素子と、
該磁気検出素子に定電流又は定電圧を与える手段と、上
記磁気検出素子が発生する電流又は電圧を検出する手段
とを有する。In order to achieve the above object, according to the present invention, a magnetic recording medium having a plurality of magnetic poles magnetized at equal intervals and a magnetic pattern of the magnetic recording medium are detected. A magnetic detector having a magnetic detection element,
A magnetic encoder in which the magnetic detection elements are arranged so as to be relatively movable within a range in which a magnetic field of the magnetic recording medium acts, wherein the magnetic detection elements are magnetic particles in an electrically conductive matrix. A giant magnetoresistive element using a thin film of a magnetic particle-dispersed giant magnetoresistive material having a structure in which is dispersed, which is formed directly or through an insulating layer on a substrate.
Of Magnetic Particle Dispersed Giant Magnetoresistive Material and Its One
The first electrode thin film electrically connected to one end, and
From a magnetic particle-dispersed giant magnetoresistive material and a first electrode.
It is formed on top of the ultra-thin film via an insulating layer and
Electricity is applied to the other end of the thin film of particle-dispersed giant magnetoresistive material.
A laminated film consisting of electrically connected second electrode thin films,
Or directly above the substrate or through an insulating layer
A second electrode thin film and an insulating layer on top of the second electrode thin film
The magnetic particle-dispersed giant magnetoresistive material formed through
There is provided a magnetic encoder, which is a laminated film including the thin film of 1. and the first electrode thin film . According to a preferred embodiment, the magnetic detector and the magnetic detection elements,
It has means for applying a constant current or constant voltage to the magnetic detection element, and means for detecting the current or voltage generated by the magnetic detection element.
【０００９】前記磁気検出素子は、急激な磁界の変化に
よるリード線からの誘導起電力によるノイズを低減し、
センサ部分の磁界のみを検出する構造とするために、磁
性粒子分散型巨大磁気抵抗材料の薄膜の両端に電気的に
接続された２本のセンサリードを絶縁層を介して積層成
膜した配線構造とする。すなわち、基板上に直接又は絶
縁層を介して形成された磁性粒子分散型巨大磁気抵抗材
料の薄膜及びその一方の端部に電気的に接続された第一
の電極薄膜（センサリード）と、これら磁性粒子分散型
巨大磁気抵抗材料の薄膜及び第一の電極薄膜の上部に絶
縁層を介して形成され、かつ上記磁性粒子分散型巨大磁
気抵抗材料の薄膜の他方の端部に電気的に接続された第
二の電極薄膜（センサリード）とからなる積層膜、ある
いは、基板上に直接又は絶縁層を介して形成された上記
第二の電極薄膜と、該第二の電極薄膜の上部に絶縁層を
介して形成された上記磁性粒子分散型巨大磁気抵抗材料
の薄膜及び第一の電極薄膜とからなる積層膜の構造とす
る。[0009] The magnetic sensing element is to reduce noise by induced electromotive force from the lead by sudden magnetic field changes in,
A wiring structure in which two sensor leads electrically connected to both ends of a thin film of a magnetic particle-dispersed giant magnetoresistive material are laminated and deposited via an insulating layer in order to provide a structure for detecting only the magnetic field of the sensor portion. And That is , a thin film of a magnetic particle-dispersed giant magnetoresistive material formed on a substrate directly or via an insulating layer and a first electrode thin film (sensor lead) electrically connected to one end of the thin film, The magnetic particle-dispersed giant magnetoresistive material thin film and the first electrode thin film are formed above the thin film via an insulating layer and electrically connected to the other end of the magnetic particle-dispersed giant magnetoresistive material thin film. A laminated film including a second electrode thin film (sensor lead), or the second electrode thin film formed on the substrate directly or via an insulating layer, and an insulating layer on the second electrode thin film. And a first electrode thin film and a thin film of the above-mentioned magnetic particle-dispersed giant magnetoresistive material formed through the structure.
【００１０】また、前記のような磁気検出素子が前記磁
気記録媒体における磁極間距離の１／２の間隔で２つ以
上形成された磁気検出器を用いることが好ましい。この
ような構成とすることにより、２つ以上の巨大磁気抵抗
素子の差動信号を回転角もしくは移動量として検出する
ことができ、また、回転駆動する励磁コイルなどの外部
磁界の影響を低減することができる。このような２つ以
上の巨大磁気抵抗素子は同一基板に形成することもでき
る。例えば、基板上に平行に離間して成膜された一対の
細長い第一の電極薄膜とこれにそれぞれ電気的に接続さ
れた磁性粒子分散型巨大磁気抵抗材料の薄膜を覆うよう
に絶縁層を積層し、該絶縁層上にさらに平行に離間して
一対の細長い第二の電極薄膜を上記磁性粒子分散型巨大
磁気抵抗材料の端部にそれぞれ電気的に接続するように
成膜する。Further, it is preferable to use a magnetic detector in which two or more magnetic detection elements as described above are formed at an interval of ½ of the distance between magnetic poles in the magnetic recording medium. With such a configuration, the differential signals of two or more giant magnetoresistive elements can be detected as a rotation angle or a movement amount, and the influence of an external magnetic field such as an exciting coil that is rotationally driven can be reduced. be able to. Two or more such giant magnetoresistive elements may be formed on the same substrate. For example, an insulating layer is laminated so as to cover a pair of elongated first electrode thin films that are formed in parallel on a substrate and are separated from each other, and a thin film of a magnetic particle dispersion type giant magnetoresistive material electrically connected to each of them. Then, a pair of elongated second electrode thin films are formed on the insulating layer so as to be spaced apart from each other in parallel so as to be electrically connected to the ends of the magnetic particle-dispersed giant magnetoresistive material.
【００１１】前記巨大磁気抵抗材料としては、電気伝導
性マトリックス中に磁性粒子を分散させた構造、好まし
くはＡｇ、Ｃｕ、Ａｕ、Ｐｔのうち少なくとも１種の元
素からなる電気伝導性マトリックス中に、Ｆｅ、Ｃｏ、
Ｎｉのうち少なくとも１種の元素からなる磁性粒子を、
好ましくは５〜５５％の原子比率で分散させた構造を有
する磁性粒子分散型（グラニュラー型）巨大磁気抵抗材
料を用いる。さらに、前記磁気記録媒体の等間隔に着磁
された複数の磁極は、高保磁力を有する磁石からなるこ
とが好ましい。The giant magnetoresistive material has a structure in which magnetic particles are dispersed in an electrically conductive matrix, preferably an electrically conductive matrix composed of at least one element selected from Ag, Cu, Au and Pt. Fe, Co,
Magnetic particles composed of at least one element of Ni,
Preferably Ru with a magnetic particle-dispersed (granular type) giant magnetoresistive material having a structure in which are dispersed at an atomic ratio of 5 to 55%. Further, it is preferable that the plurality of magnetic poles magnetized at equal intervals in the magnetic recording medium are magnets having a high coercive force.
【００１２】[0012]
【発明の実施の形態】前記のように、本発明の磁気式エ
ンコーダは、磁気検出素子が磁性粒子分散型の巨大磁気
抵抗材料（巨大磁気抵抗効果を有する材料をいう）の薄
膜を用いた巨大磁気抵抗素子からなるため、磁気検出素
子の微細・小型化、高磁界中での磁界測定、高周波対応
が可能であり、また、温度変化による出力変化が小さ
く、しかも汚れなどの影響を受けない高感度、高出力、
高分解能の磁気式エンコーダを提供することが可能とな
る。上記巨大磁気抵抗材料は、磁性粒子分散型巨大磁気
抵抗効果材料からなり、少なくとも５ｋＨｚ以上の交流
磁界を信号として読み取ることができる。BEST MODE FOR CARRYING OUT THE INVENTION As described above, in the magnetic encoder of the present invention, the magnetic detection element is a giant magnetic resistance dispersed giant magnetic resistance material (referred to as a material having a giant magnetoresistance effect). Since it consists of a magnetoresistive element, it is possible to miniaturize and miniaturize the magnetic detection element, measure the magnetic field in a high magnetic field, and support high frequencies.Also, the output change due to temperature change is small and it is not affected by dirt etc. Sensitivity, high output,
It is possible to provide a high resolution magnetic encoder. The giant magnetoresistance material can be read magnetic particles dispersed giant magneto-resistive materials or Rannahli, an AC magnetic field over at least 5kHz as a signal.
【００１３】ここで巨大磁気抵抗（Giant Magnetoresis
tance,ＧＭＲ）効果とは、エイ．イー．ベルコウィッツ
（A.E. Berkowitz）ら、Phys. Rev. Lett. 68 (1992),
3745頁やジェイ．キュー．ズィエ（J.Q. Xiao）ら、Phy
s. Rev. Lett. 68 (1992), 3749頁に報告されている磁
性粒子分散型磁気抵抗効果を指す。これらの材料の磁気
抵抗効果は、潟岡ら「まてりあ」第３３巻第２号、１９
９４年、１６５頁に解説されているように、磁性体（析
出粒子もしくは多層膜）の磁化と伝導を担う電子のスピ
ン依存散乱によるとされている。従って、磁性体として
Ｃｏ、Ｎｉ、Ｆｅやそれらの合金を用いているので、少
なくとも３００℃まで磁化変化が無く、大きな磁気抵抗
効果が得られる。Here, Giant Magnetoresis
tance, GMR) effect, E. AE Berkowitz et al., Phys. Rev. Lett. 68 (1992),
Page 3745 and Jay. queue. JQ Xiao et al., Phy
s. Rev. Lett. 68 (1992 ), refers to a magnetic particle-dispersed magnetoresistive effect reported in the pages 3749. The magnetoresistive effect of these materials is described in "Materia", Vol.
As explained on page 165 in 1994, it is said to be due to spin-dependent scattering of electrons responsible for the magnetization and conduction of the magnetic substance (precipitated particles or multilayer film). Therefore, since Co, Ni, Fe, or an alloy thereof is used as the magnetic substance, there is no change in magnetization up to at least 300 ° C., and a large magnetoresistive effect can be obtained.
【００１４】前記磁性粒子分散型巨大磁気抵抗材料は、
Ａｇ、Ｃｕ、Ａｕ等の電気伝導性材料もしくは非磁性
（常磁性、反磁性）材料中に最大長径が約５〜５００ｎ
ｍのＦｅ、Ｃｏ、Ｎｉ等の強磁性粒子が分散した材料か
らなる。 The magnetic particle-dispersed giant magnetoresistive material comprises
The maximum major axis in an electrically conductive material such as Ag, Cu, Au or a non-magnetic (paramagnetic, diamagnetic) material is about 5 to 500 n.
m of Fe, Co, ing of a material ferromagnetic particles are dispersed such as Ni.
【００１５】これらの材料の特徴として、数ｋＯｅ以上
の磁界においても、磁気抵抗変化があるため、モータ内
にセンサを配してもロータの回転に伴う磁界変化を測定
することができる。それに加えて、これらの材料は配線
がホール素子の半分の２本で済むために、配線が簡単で
小型化が容易である。つまり、磁気式エンコーダに要求
される「高磁界特性」、「高周波特性」、「耐磁界外
乱」、「小型化」の要件を備えている。A characteristic of these materials is that even in a magnetic field of several kOe or more, there is a change in magnetic resistance. Therefore, even if a sensor is provided in the motor, it is possible to measure the change in magnetic field due to rotation of the rotor. In addition, these materials require only two wires, which is half of the Hall element, so that the wiring is simple and the miniaturization is easy. That is, the magnetic encoder has the requirements of "high magnetic field characteristics", "high frequency characteristics", "magnetic field resistance disturbance", and "miniaturization".
【００１６】従来知られている巨大磁気抵抗材料のうち
でも、磁気式エンコーダに利用するためには、磁性粒子
分散型巨大磁気抵抗材料を用いることが好ましい。これ
は、超巨大磁気抵抗効果の場合、温度特性をよくするた
めに高温（７００〜９００℃）で熱処理を必要とするた
め、作製プロセスが難しいこと、また電気抵抗が数ｋΩ
と高いため電気を流しにくいためである。Among known giant magnetoresistive materials, it is preferable to use a magnetic particle dispersion type giant magnetoresistive material for use in a magnetic encoder. This is because the super giant magnetoresistive effect requires a heat treatment at a high temperature (700 to 900 ° C.) in order to improve the temperature characteristics, which makes the manufacturing process difficult and has an electric resistance of several kΩ.
Because it is expensive, it is difficult to pass electricity.
【００１７】磁性粒子分散型巨大磁気抵抗材料は、好ま
しくは、一般式：ＮＭ100-XＴＭX（但し、ＮＭはＡｇ、
Ｃｕ、Ａｕ、Ｐｔのうち少なくとも１種の元素、ＴＭは
Ｆｅ、Ｃｏ、Ｎｉのうち少なくとも１種の元素であり、
ｘは原子％で５≦ｘ≦５５、好ましくは１０≦ｘ≦３
５）で示される組成を有する。上記一般式で示される組
成の磁性粒子分散型巨大磁気抵抗材料において、非磁性
材料ＮＭは最大２０ａｔ％まで、好ましくは１０ａｔ％
以下の範囲内でＡｌ、Ｔｉ、Ｐｄ、Ｒｈなど他の元素の
１種以上を含むことができる。これらの元素は、磁気抵
抗効果を低下させ、感度を低くするが、反面、Ａｌ、Ｔ
ｉは磁気抵抗効果の温度依存性を小さくし、一方、Ｐ
ｄ、Ｐｔ、Ｒｈは電気抵抗を増大させることで、配線を
含むセンサ全体の磁気抵抗効果を大きくする効果があ
る。また、強磁性材料ＴＭはＦｅ、Ｃｏ、Ｎｉ以外にＣ
ｒ、Ｍｎなどの元素を最大５ａｔ％までの範囲内で含む
ことができる。特にＣｒ、Ｍｎは磁気抵抗効果を減少さ
せるが、磁性粒子の粗大化を防ぎ、耐熱性を上げること
ができる。The magnetic particle-dispersed giant magnetoresistive material is preferably of the general formula: NM 100-X TM X (where NM is Ag,
At least one element of Cu, Au and Pt, TM is at least one element of Fe, Co and Ni,
x is atomic% and 5 ≦ x ≦ 55, preferably 10 ≦ x ≦ 3
It has a composition shown in 5). In the magnetic particle-dispersed giant magnetoresistive material having the composition represented by the above general formula, the nonmagnetic material NM can be up to 20 at%, preferably 10 at%.
One or more of other elements such as Al, Ti, Pd, and Rh can be included within the following range. These elements lower the magnetoresistive effect and lower the sensitivity, but on the other hand, Al, T
i reduces the temperature dependence of the magnetoresistive effect, while P
By increasing the electric resistance, d, Pt, and Rh have the effect of increasing the magnetoresistive effect of the entire sensor including the wiring. Further, the ferromagnetic material TM is C in addition to Fe, Co and Ni.
Elements such as r and Mn can be contained within the range of up to 5 at%. In particular, Cr and Mn reduce the magnetoresistive effect, but can prevent coarsening of the magnetic particles and increase the heat resistance.
【００１８】[0018]
【実施例】以下、本発明の磁気式エンコーダについて添
付図面を参照しながら説明する。図１は、本発明の磁気
検出器の磁気検出素子１の一実施例を示す平面図、図２
はそのII−II線断面図である。図１及び図２において、
符号３は前記したような磁性粒子分散型巨大磁気抵抗材
料よりなる薄膜（センサ素子）を示している。図１及び
図２に明瞭に示されているように、基板２の上には細長
い銅製の第一電極薄膜４が形成され、該第一電極薄膜４
の先端部に上記巨大磁気抵抗材料の薄膜３が配設されて
いる。上記巨大磁気抵抗材料薄膜３及び第一電極薄膜４
の上には、これらを覆うようにＡｌ2Ｏ3製の絶縁層５が
積層されている。但し、第一電極薄膜４の後端部はリー
ド線接続のために露出している。該絶縁層５の上には、
上記第一電極薄膜４と整合する位置に、上記巨大磁気抵
抗材料薄膜３と電気的に接続されるように細長い銅製の
第二電極薄膜６が形成されている。DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic encoder of the present invention will be described below with reference to the accompanying drawings. 1 is a plan view showing an embodiment of a magnetic detection element 1 of a magnetic detector of the present invention, FIG.
Is a sectional view taken along line II-II. 1 and 2,
Reference numeral 3 indicates a thin film (sensor element) made of the above-mentioned giant magnetic resistance material in which magnetic particles are dispersed. As shown clearly in FIGS. 1 and 2, an elongated copper first electrode thin film 4 is formed on a substrate 2, and the first electrode thin film 4 is formed.
The thin film 3 of the giant magnetoresistive material is disposed at the tip of the. The giant magnetoresistive material thin film 3 and the first electrode thin film 4
An insulating layer 5 made of Al 2 O 3 is laminated on the above so as to cover them. However, the rear end of the first electrode thin film 4 is exposed for connecting the lead wire. On the insulating layer 5,
An elongated copper second electrode thin film 6 is formed at a position aligned with the first electrode thin film 4 so as to be electrically connected to the giant magnetoresistive material thin film 3.
【００１９】前記巨大磁気抵抗材料薄膜３の形状は、長
さ５ｍｍ以下、幅０．５ｍｍ以下の矩形状が適当であ
る。前記電極薄膜４、６は、Ａｌ、Ｃｕ、Ｃｒ、Ｔａも
しくはＭｏ又はそれらの合金等の導電性材料から作製で
きるが、これらの中でもＣｕが好ましい。また、前記絶
縁層５としては、Ａｌ2Ｏ3、ＳｉＯ2、ＭｇＯ等を用い
ることができる。絶縁層５の厚さは０．５ｎｍ以上、
１，０００ｎｍ以下が適当であり、好ましくは１０ｎｍ
以上、１００ｎｍ以下がよい。別の好適な態様によれ
ば、前記基板２として、又はその裏側にケイ素鋼板やパ
ーマロイ、ＣｏＦｅＳｉＢアモルファス合金等の軟磁性
体を取り付けたものを用いる。このように軟磁性体を利
用して磁束を収束させることにより、さらに感度が向上
し、従って検出器の設置場所の制約が緩和される。
A suitable shape of the giant magnetoresistive material thin film 3 is a rectangular shape having a length of 5 mm or less and a width of 0.5 mm or less. The electrode thin films 4 and 6 can be made of a conductive material such as Al, Cu, Cr, Ta or Mo or an alloy thereof, and Cu is preferable among them. Further, as the insulating layer 5, Al 2 O 3 , SiO 2 , MgO or the like can be used. The thickness of the insulating layer 5 is 0.5 nm or more,
1,000 nm or less is suitable, preferably 10 nm
As described above, 100 nm or less is preferable. According to another preferred mode, a soft magnetic material such as a silicon steel plate, permalloy, or CoFeSiB amorphous alloy is attached as the substrate 2 or on the back side thereof. By thus concentrating the magnetic flux using the soft magnetic material, the sensitivity is further improved, and therefore, the restriction on the installation location of the detector is alleviated.
【００２０】図３は、本発明の磁気検出素子をロータリ
ーエンコーダに応用した例の概略基本構成を示してい
る。図３において、符号１０はモータ等の回転駆動源１
３の回転軸１２に取り付けられた回転ドラム状の磁気記
録媒体であり、その外周面に永久磁石が、円周方向にＮ
Ｓ極１１が等間隔に出現するように固着されている。磁
極としては強力磁石（ＳｍＣｏ，ＮｄＦｅＢなどの希土
類磁石）を用いることが好ましい。磁気検出素子１ａ
は、上記磁気記録媒体１０と対向するように、かつ、Ｎ
Ｓ極による磁界が作用する範囲内に所定の間隙を介して
配設されており、電源１７からリード線１４を介して定
電流又は定電圧が与えられている。なお、図３に示す磁
気検出素子１ａは、絶縁層を介して基板上に積層された
上下の電極薄膜の下端部が二股状に拡げられた構造を有
するが、その基本的な構造は前記図１及び図２に示すも
のと同様である。FIG. 3 shows a schematic basic configuration of an example in which the magnetic detection element of the present invention is applied to a rotary encoder. In FIG. 3, reference numeral 10 is a rotary drive source 1 such as a motor.
3 is a rotating drum-shaped magnetic recording medium attached to the rotating shaft 12 of No. 3, in which a permanent magnet is provided on the outer peripheral surface thereof in a circumferential direction of N.
The S poles 11 are fixed so that they appear at equal intervals. It is preferable to use a strong magnet (rare earth magnet such as SmCo or NdFeB) as the magnetic pole. Magnetic detection element 1a
So as to face the magnetic recording medium 10 and N
It is arranged with a predetermined gap in the range where the magnetic field by the S pole acts, and a constant current or a constant voltage is applied from the power supply 17 through the lead wire 14. The magnetic sensing element 1a shown in FIG. 3 has a structure in which the lower end portions of the upper and lower electrode thin films laminated on the substrate via an insulating layer are spread in a bifurcated shape. 1 and that shown in FIG.
【００２１】このような構成において、磁気記録媒体１
０を回転させると、着磁された磁気パターンに対応して
磁気検出素子１ａに加わる磁界が周期的に変化する。こ
の変化は磁気検出素子１ａにより磁気抵抗の変化として
検出され、電流変化又は電圧変化の出力信号が得られる
ことになる。この出力信号は増幅回路１５により増幅し
て制御系１６に送られる。このようにして、磁気記録媒
体１０の回転角もしくは移動量や回転速度を検出するこ
とができる。In such a structure, the magnetic recording medium 1
When 0 is rotated, the magnetic field applied to the magnetic detection element 1a changes periodically corresponding to the magnetized magnetic pattern. This change is detected by the magnetic detection element 1a as a change in magnetic resistance, and an output signal of current change or voltage change is obtained. This output signal is amplified by the amplifier circuit 15 and sent to the control system 16. In this way, the rotation angle, the movement amount, or the rotation speed of the magnetic recording medium 10 can be detected.
【００２２】なお、図３は本発明の磁気検出素子をロー
タリーエンコーダに応用した場合の概略的な基本構成を
示しており、エンコーダの構成自体は従来公知の種々の
形態を採用できることは言うまでもない。例えば、前記
した特開昭５９−１４７２１３号、特開平２−１９５２
８４号、特開平７−１３９９６６号等に記載されている
ような態様で磁気記録媒体の表面にアブソリュート相、
インクリメンタル相を形成することができる。It should be noted that FIG. 3 shows a schematic basic structure when the magnetic detection element of the present invention is applied to a rotary encoder, and it goes without saying that the structure itself of the encoder can adopt various conventionally known forms. For example, JP-A-59-147213 and JP-A-2-1952 mentioned above.
No. 84, JP-A-7-139966, etc., and an absolute phase on the surface of the magnetic recording medium,
An incremental phase can be formed.
【００２３】図４は、本発明の磁気検出素子をリニアエ
ンコーダに応用した例の概略基本構成を示している。こ
のリニアエンコーダにおいては、表面に所定のパターン
でＮＳ極１１ａが形成され、移動対象物１８に固定され
た細長いプレート状の磁気記録媒体１０ａが用いられて
いる以外、他の構成は基本的には前記ロータリーエンコ
ーダの場合と同様である。この場合にも、磁気検出素子
１ａは、磁気記録媒体１０ａと対向するようにその近傍
に配置されている。FIG. 4 shows a schematic basic configuration of an example in which the magnetic detecting element of the present invention is applied to a linear encoder. In this linear encoder, the NS pole 11a is formed in a predetermined pattern on the surface, and the elongated plate-shaped magnetic recording medium 10a fixed to the moving object 18 is used, and other configurations are basically the same. This is similar to the case of the rotary encoder. Also in this case, the magnetic detection element 1a is arranged in the vicinity of the magnetic recording medium 10a so as to face the magnetic recording medium 10a.
【００２４】以下、本発明の効果を具体的に確認した実
施例を示す。磁性粒子分散型巨大磁気抵抗材料は、Ａｇ
ターゲットもしくはＣｕターゲット上にＣｏチップもし
くはＮｉ0.66Ｃｏ0.18Ｆｅ0.16合金チップを均等に配し
た複合ターゲットを用いて作製した。成膜条件及び熱処
理条件は以下のとおりである。
成膜方法：ＲＦマグネトロンスパッタ
基板：Ｓｉウェーハ
基板温度：１００℃
雰囲気：Ａｒ０．６Ｐａ
スパッタ電力：１００Ｗ
薄膜組成：Ａｇ70Ｃｏ30、Ａｇ75（Ｎｉ0.66Ｃｏ0.18Ｆ
ｅ0.16）25の２種
膜厚：１０〜５００ｎｍ
熱処理：
温度：２００℃
時間：０．５時間
雰囲気：真空中
膜厚１０ｎｍでの磁気抵抗効果：１０ｋＯｅの磁界で約
１０％の磁気抵抗比（ＭＲ比）が得られた。なお、この
磁気抵抗比は、下記式により求めた値である。 ＭＲ比
（％）＝（Ｒ（０）−Ｒ（Ｈ））／Ｒ（０）×１００
Ｒ（０）：磁界がないときの電気抵抗
Ｒ（Ｈ）：磁界が印加されたときの電気抵抗Examples in which the effects of the present invention have been specifically confirmed will be shown below. The magnetic particle-dispersed giant magnetoresistive material is Ag
It was produced using a composite target in which Co chips or Ni 0.66 Co 0.18 Fe 0.16 alloy chips were evenly arranged on the target or Cu target. Film forming conditions and heat treatment conditions are as follows. Film forming method: RF magnetron sputter substrate: Si wafer substrate temperature: 100 ° C. atmosphere: Ar 0.6 Pa Sputtering power: 100 W Thin film composition: Ag 70 Co 30 , Ag 75 (Ni 0.66 Co 0.18 F
e 0.16 ) 25 two kinds Film thickness: 10-500 nm Heat treatment: Temperature: 200 ° C. Time: 0.5 hour Atmosphere: Magnetoresistance effect in vacuum film thickness of 10 nm: Magnetoresistance ratio of about 10% in a magnetic field of 10 kOe ( The MR ratio) was obtained. The magnetic resistance ratio is a value obtained by the following formula. MR ratio (%) = (R (0) −R (H)) / R (0) × 100 R (0): Electric resistance when no magnetic field is applied R (H): Electric resistance when a magnetic field is applied
【００２５】上記の方法により、ガラス基板上に巨大磁
気抵抗材料の薄膜を長さ０．５ｍｍ、幅０．１ｍｍの矩
形状に成膜し、厚さを１０ｎｍ〜５００ｎｍまで調整
し、センサの抵抗として２Ωから５０Ωまで変え、また
Ｃｕ電極もしくは銀ペーストにより電極を作製し、磁気
検出素子を作製した。約１ｍｍ厚さの磁石板（表面磁界
５００Ｏｅ）をＮＳ極が交互になるように積み重ね、１
０枚おきに１ｋΩの磁石を挟んだものを磁気記録媒体と
し、これを上記磁気検出素子と対向させて移動させるこ
とにより、磁気記録媒体の位置変化だけでなく、絶対位
置が検出でき、また１５０℃の温度条件下でも検出可能
であることを確認した。According to the above method, a thin film of a giant magnetoresistive material is formed on a glass substrate in a rectangular shape having a length of 0.5 mm and a width of 0.1 mm, and the thickness is adjusted to 10 nm to 500 nm, and the resistance of the sensor is adjusted. Was changed from 2Ω to 50Ω, and an electrode was prepared with a Cu electrode or silver paste to prepare a magnetic detection element. A magnet plate (surface magnetic field 500 Oe) with a thickness of about 1 mm is stacked so that the NS poles alternate, 1
A magnetic recording medium having a 1 kΩ magnet sandwiched between every two sheets is used as a magnetic recording medium, and the magnetic recording medium is moved so as to face the magnetic detecting element, whereby not only the position change of the magnetic recording medium but also the absolute position can be detected. It was confirmed that detection was possible even under the temperature condition of ° C.
【００２６】[0026]
【発明の効果】以上のように、本発明の磁気式エンコー
ダは、磁気検出素子として磁性粒子分散型巨大磁気抵抗
材料を用いているため、高温下や粉塵環境下においても
使用でき、かつ小型で分解能の高い磁気式エンコーダを
安価に作製することが可能となった。また、高磁界環境
下でも磁気検出が可能であり、また検出磁界の発生源に
強力磁石を用いることによって、外部磁界（ノイズ）の
影響を受け難くなり、磁気シールドの必要がなく、高い
信頼性が得られる。さらに、高周波磁界の測定ができ、
また埃等の汚れが付着しても感度低下がない。従って、
ヒーター用、エンジン用等の各種ロータリーエンコー
ダ、リニアエンコーダとして有利に使用することができ
る。As is evident from the foregoing description, the magnetic encoder of the present invention, due to the use of magnetic particles dispersed giant magneto-resistive material as a magnetic sensor, it can be used at high temperatures or dust environment, and It has become possible to manufacture a compact magnetic encoder with high resolution at low cost. In addition, magnetic detection is possible even in a high magnetic field environment, and by using a strong magnet as the source of the detected magnetic field, it is less likely to be affected by external magnetic fields (noise), and there is no need for magnetic shielding, resulting in high reliability. Is obtained. Furthermore, high frequency magnetic field can be measured,
Further, even if dirt such as dust adheres, the sensitivity does not decrease. Therefore,
It can be advantageously used as various rotary encoders and linear encoders for heaters and engines.
【図１】本発明の磁気検出素子の一実施例を示す平面図
である。FIG. 1 is a plan view showing an embodiment of a magnetic detection element of the present invention.
【図２】図１のII−II線断面図である。FIG. 2 is a sectional view taken along line II-II in FIG.
【図３】本発明の磁気検出素子をロータリーエンコーダ
に応用した実施例を示す概略基本構成図である。FIG. 3 is a schematic basic configuration diagram showing an embodiment in which the magnetic detection element of the present invention is applied to a rotary encoder.
【図４】本発明の磁気検出素子をリニアエンコーダに応
用した実施例を示す概略基本構成図である。FIG. 4 is a schematic basic configuration diagram showing an embodiment in which the magnetic detection element of the present invention is applied to a linear encoder.
１，１ａ 磁気検出素子 ２ 基板 ３ 巨大磁気抵抗材料薄膜 ４ 第一電極薄膜 ５ 絶縁層 ６ 第二電極薄膜 １０，１０ａ 磁気記録媒体 １１，１１ａ ＮＳ極 １２ 回転軸 １３ 回転駆動源（モータ） １５ 増幅回路 １６ 制御系 １７ 電源 1,1a Magnetic detection element 2 substrates 3 Giant magnetoresistive material thin film 4 First electrode thin film 5 insulating layers 6 Second electrode thin film Magnetic recording medium 11,11a NS pole 12 rotation axes 13 Rotary drive source (motor) 15 Amplification circuit 16 Control system 17 power supply
───────────────────────────────────────────────────── フロントページの続き (72)発明者 三浦 由則 宮城県仙台市太白区茂庭台４丁目26番３ 号 (56)参考文献 特開 平９−292402（ＪＰ，Ａ) 特開 平８−264860（ＪＰ，Ａ) 特開 平７−77531（ＪＰ，Ａ) 特開 平８−184463（ＪＰ，Ａ) 特開 平９−159684（ＪＰ，Ａ) 特開 平10−10141（ＪＰ，Ａ) 特開 平10−227809（ＪＰ，Ａ) 特開 平10−163544（ＪＰ，Ａ) 特開 平４−280483（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) G01D 5/00 - 5/62 G01B 7/00 - 7/34 G01P 1/00 - 3/80 G01R 33/00 - 33/26 H01L 43/00 - 43/14 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor, Yunori Miura 4-26-3, Moiwadai, Taishiro-ku, Sendai-shi, Miyagi (56) References JP-A-9-292402 (JP, A) JP-A-8-264860 (JP, A) JP-A-7-77531 (JP, A) JP-A-8-184463 (JP, A) JP-A-9-159684 (JP, A) JP-A-10-10141 (JP, A) Kaihei 10-227809 (JP, A) JP 10-163544 (JP, A) JP 4-280483 (JP, A) (58) Fields investigated (Int.Cl. 7 , DB name) G01D 5 / 00-5/62 G01B 7/00-7/34 G01P 1/00-3/80 G01R 33/00-33/26 H01L 43/00-43/14
Claims (6)
磁気記録媒体と、該磁気記録媒体の磁気パターンを検出
する磁気検出素子を有する磁気検出器とを備え、該磁気
検出素子を上記磁気記録媒体の磁界が作用する範囲内で
相対移動自在に対向して配設してなる磁気式エンコーダ
であって、上記磁気検出素子が、電気伝導性マトリック
ス中に磁性粒子を分散させた構造を有する磁性粒子分散
型巨大磁気抵抗材料の薄膜を用いた巨大磁気抵抗素子で
あって、基板上に直接又は絶縁層を介して形成された磁
性粒子分散型巨大磁気抵抗材料の薄膜及びその一方の端
部に電気的に接続された第一の電極薄膜と、これら磁性
粒子分散型巨大磁気抵抗材料の薄膜及び第一の電極薄膜
の上部に絶縁層を介して形成され、かつ上記磁性粒子分
散型巨大磁気抵抗材料の薄膜の他方の端部に電気的に接
続された第二の電極薄膜とからなる積層膜、あるいは、
基板上に直接又は絶縁層を介して形成された上記第二の
電極薄膜と、該第二の電極薄膜の上部に絶縁層を介して
形成された上記磁性粒子分散型巨大磁気抵抗材料の薄膜
及び第一の電極薄膜とからなる積層膜であることを特徴
とする磁気式エンコーダ。1. A magnetic recording medium having a plurality of magnetic poles magnetized at equal intervals, and a magnetic detector having a magnetic detecting element for detecting a magnetic pattern of the magnetic recording medium. A magnetic encoder, which is arranged so as to be relatively movable within a range in which a magnetic field of a magnetic recording medium acts, wherein the magnetic detection element has a structure in which magnetic particles are dispersed in an electrically conductive matrix. a giant magneto-resistive element using a thin film of magnetic particles dispersed giant magnetoresistive material having
The magnetic field formed directly on the substrate or through an insulating layer.
Thin film of magnetic particles dispersed giant magnetoresistive material and its one end
Electrode thin film electrically connected to the
Particle-dispersed giant magnetoresistive material thin film and first electrode thin film
Is formed on the upper part of the insulating layer through an insulating layer,
Electrically contact the other end of the thin film of diffused giant magnetoresistive material.
A laminated film consisting of a second electrode thin film continued, or
The second above formed directly on the substrate or through the insulating layer
An electrode thin film and an insulating layer on the upper part of the second electrode thin film
The formed thin film of the magnetic particle-dispersed giant magnetoresistive material
And a first electrode thin film, which is a laminated film .
と、該磁気検出素子に定電流又は定電圧を与える手段
と、上記磁気検出素子が発生する電流又は電圧を検出す
る手段とを有する請求項１に記載の磁気式エンコーダ。Wherein said magnetic detector, wherein with said magnetic sensing element, and means for providing a constant current or constant voltage to the magnetic sensing element, and means for detecting a current or voltage the magnetic detecting element is generated Item 1. The magnetic encoder according to Item 1.
おける磁極間距離の１／２の間隔で２つ以上形成された
磁気検出器を有する請求項１又は２に記載の磁気式エン
コーダ。3. A magnetic encoder according to claim 1 or 2 having a magnetic detector formed of two or more at half the spacing of the pole distance of the magnetic detection element is the magnetic recording medium.
が、Ａｇ、Ｃｕ、Ａｕ、Ｐｔのうち少なくとも１種の元
素からなる電気伝導性マトリックス中に、Ｆｅ、Ｃｏ、
Ｎｉのうち少なくとも１種の元素からなる磁性粒子を分
散させた構造を有する請求項１乃至３のいずれか一項に
記載の磁気式エンコーダ。4. The magnetic particle-dispersed giant magnetoresistive material comprises an electrically conductive matrix made of at least one element selected from Ag, Cu, Au, and Pt in an electrically conductive matrix.
Magnetic encoder according to any one of claims 1 to 3 having a structure obtained by dispersing magnetic particles consisting of at least one element selected and Ni.
ける含有割合が原子比率で５〜５５％である請求項４に
記載の磁気式エンコーダ。5. The magnetic encoder according to claim 4 , wherein the content ratio of the magnetic particles in the giant magnetoresistive material is 5 to 55% in atomic ratio.
複数の磁極が、高保磁力を有する磁石からなる請求項１
乃至５のいずれか一項に記載の磁気式エンコーダ。6. The magnetic poles magnetized at equal intervals in the magnetic recording medium are magnets having a high coercive force.
The magnetic encoder according to any one of items 1 to 5 .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01533999A JP3523797B2 (en) | 1999-01-25 | 1999-01-25 | Magnetic encoder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01533999A JP3523797B2 (en) | 1999-01-25 | 1999-01-25 | Magnetic encoder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000213957A JP2000213957A (en) | 2000-08-04 |
| JP3523797B2 true JP3523797B2 (en) | 2004-04-26 |
Family
ID=11886041
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01533999A Expired - Fee Related JP3523797B2 (en) | 1999-01-25 | 1999-01-25 | Magnetic encoder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3523797B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006292534A (en) * | 2005-04-11 | 2006-10-26 | Daido Steel Co Ltd | Rotor position detecting sensor for brushless motor |
| JP4739963B2 (en) | 2006-01-18 | 2011-08-03 | アルプス電気株式会社 | In-vehicle GMR angle sensor |
-
1999
- 1999-01-25 JP JP01533999A patent/JP3523797B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2000213957A (en) | 2000-08-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6285101B1 (en) | Rotational angle detector for brushless motor and brushless motor using the detector | |
| US6184680B1 (en) | Magnetic field sensor with components formed on a flexible substrate | |
| US6642714B2 (en) | Thin-film magnetic field sensor | |
| US6437558B2 (en) | Passive solid-state magnetic field sensors and applications therefor | |
| US6640652B2 (en) | Rotation angle sensor capable of accurately detecting rotation angle | |
| US6054226A (en) | Magnetoresistive element and magnetic detector and use thereof | |
| EP1400957A2 (en) | Spin-valve head containing partial current-screening-layer, production method of said head, and current-screening method | |
| EP1151482B1 (en) | Spin dependent tunneling sensor | |
| US6650112B2 (en) | Magnetics impedance element having a thin film magnetics core | |
| WO1995010123A1 (en) | Magneto-resistance device, and magnetic head employing such a device | |
| EP1198718A1 (en) | Passive solid-state magnetic field sensors and applications therefor | |
| JPS649649B2 (en) | ||
| JP3341237B2 (en) | Magnetic sensor element | |
| JP2000193407A (en) | Magnetic positioning device | |
| US6669787B2 (en) | Method of manufacturing a spin valve structure | |
| JP3523797B2 (en) | Magnetic encoder | |
| JP3731288B2 (en) | Multilayer magnetic field detector | |
| JP2000180524A (en) | Magnetic field sensor | |
| US6335578B1 (en) | Brushless DC motor | |
| JP3050094B2 (en) | Spin valve element | |
| JP3282444B2 (en) | Magnetoresistive element | |
| JP4237855B2 (en) | Magnetic field sensor | |
| Delooze et al. | AC biased sub-nano-tesla magnetic field sensor for low-frequency applications utilizing magnetoimpedance in multilayer films | |
| JPH10270775A (en) | Magneto-resistance effect element and revolution sensor using the same | |
| JP2004333217A (en) | Magnetic field detector |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20031226 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20040203 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20040209 |
|
| LAPS | Cancellation because of no payment of annual fees |