JPH0552584A - Magnetic encoder - Google Patents

Magnetic encoder

Info

Publication number
JPH0552584A
JPH0552584A JP21694291A JP21694291A JPH0552584A JP H0552584 A JPH0552584 A JP H0552584A JP 21694291 A JP21694291 A JP 21694291A JP 21694291 A JP21694291 A JP 21694291A JP H0552584 A JPH0552584 A JP H0552584A
Authority
JP
Japan
Prior art keywords
magnetic
mask member
permanent magnet
pitch
moving body
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
Application number
JP21694291A
Other languages
Japanese (ja)
Inventor
Tetsuya Ito
哲也 伊東
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.)
Toshiba Corp
Original Assignee
Toshiba Corp
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 Toshiba Corp filed Critical Toshiba Corp
Priority to JP21694291A priority Critical patent/JPH0552584A/en
Publication of JPH0552584A publication Critical patent/JPH0552584A/en
Pending legal-status Critical Current

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  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Transmission And Conversion Of Sensor Element Output (AREA)

Abstract

PURPOSE:To improve resolutions sufficiently even in miniaturization as a whole. CONSTITUTION:A rotary disc 11 as moving body made up of a disc-shaped mask member 14 and a disc-shaped permanent magnet 15 integrated. The permanent magnet 15 is magnetized in a single pole in the axial direction thereof and a pair of magnetic poles is provided on the surface and back thereof differing in polarity. The mask member 14 comprises a soft magnetic body and a plurality of slits 14a are formed on the outer peripheral part thereof in a ring at a specified pitch. With such an arrangement, at the mask member 14, the slit 14a as a magnetic shielding section with a large magnetic reluctance and a magnetic path section 14b (a part between the slits 14a) with a small magnetic reluctance are formed alternately along the direction of rotation of the rotary disc 11. A magnetic pole 12 is formed on the outer peripheral part of the rotary disc 11 having a magnetic field from the permanent magnet 15 varying in intensity alternately along the direction of movement thereof.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、回転運動或は直線運動
される移動体の変位に応じた信号を磁気センサを利用し
て得るようにした磁気式エンコーダ、特には小形化が必
要な用途に好適する磁気式エンコーダに関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic encoder adapted to obtain a signal corresponding to a displacement of a moving body which is rotated or linearly moved by using a magnetic sensor, and in particular, an application requiring miniaturization. The present invention relates to a magnetic encoder suitable for.

【0002】[0002]

【従来の技術】例えば磁気式ロータリエンコーダにおい
ては、磁極列を備えた回転体の変位を磁気センサにより
検出する構成とされるものであり、その一例を図4に示
す。
2. Description of the Related Art For example, a magnetic rotary encoder has a structure in which the displacement of a rotating body having a magnetic pole array is detected by a magnetic sensor, an example of which is shown in FIG.

【0003】即ち、図4(a)において、軸1aを中心
に回転する回転ディスク1は、少なくとも外周縁部が磁
性体により形成されており、その縁部を所定ピッチにて
交互に異なる極性に着磁することによって複数個の磁極
2が形成されている。磁気センサ3は、磁極2の着磁ピ
ッチと同一ピッチの感磁パターンを備えた強磁性体磁気
抵抗素子或は半導体磁気抵抗素子より成るもので、前記
磁極2の回転軌跡に対してその軸方向から近接対向する
ように配置される。
That is, in FIG. 4 (a), at least the outer peripheral edge portion of a rotary disk 1 which rotates about a shaft 1a is formed of a magnetic material, and the edge portions thereof are alternately arranged at a predetermined pitch and have different polarities. A plurality of magnetic poles 2 are formed by magnetizing. The magnetic sensor 3 is composed of a ferromagnetic magnetoresistive element or a semiconductor magnetoresistive element having a magnetic sensitive pattern having the same pitch as the magnetizing pitch of the magnetic pole 2, and its axial direction with respect to the rotation locus of the magnetic pole 2. Are arranged so as to closely face each other.

【0004】他の構成例を示す図4(b)において、軸
4aを中心に回転する回転ドラム4は、少なくとも外周
端面部が磁性体により形成されており、その端面部を所
定ピッチにて交互に異なる極性に着磁することによって
複数個の磁極5が形成されており、この場合、磁気セン
サ3は、磁極5の回転軌跡に対してその径方向から近接
対向するように配置される。また、磁気センサ3に代え
て、磁性体と検出コイルとを組み合わせて成る磁気ヘッ
ドを使用することも行われる。
In FIG. 4 (b) showing another configuration example, at least the outer peripheral end face of a rotary drum 4 rotating about a shaft 4a is formed of a magnetic material, and the end face portions thereof are alternately arranged at a predetermined pitch. A plurality of magnetic poles 5 are formed by magnetizing the magnetic poles with different polarities. In this case, the magnetic sensor 3 is arranged so as to closely oppose the rotational trajectory of the magnetic pole 5 in the radial direction. Further, instead of the magnetic sensor 3, a magnetic head formed by combining a magnetic body and a detection coil may be used.

【0005】[0005]

【発明が解決しようとする課題】上記のように構成され
たロータリエンコーダを小形化する場合には、回転ディ
スク1の磁極2或は回転ドラム4の磁極5の着磁ピッチ
を微細に設定する必要がある。しかしながら、実際に
は、着磁ヘッドの寸法上の制約などから、上記のように
着磁ピッチを微細に設定することは非常に困難であり、
結果的にロータリエンコーダとしての分解能が低くなる
という欠点があった。
In miniaturizing the rotary encoder constructed as described above, it is necessary to finely set the magnetizing pitch of the magnetic pole 2 of the rotary disk 1 or the magnetic pole 5 of the rotary drum 4. There is. However, in practice, it is very difficult to finely set the magnetizing pitch as described above, due to the dimensional restrictions of the magnetizing head,
As a result, there is a drawback that the resolution as a rotary encoder is lowered.

【0006】本発明は上記事情に鑑みてなされたもので
あり、その目的は、全体を小形化した場合でも分解能を
十分に向上させることができる磁気式エンコーダを提供
するにある。
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a magnetic encoder capable of sufficiently improving the resolution even when the overall size is reduced.

【0007】[0007]

【課題を解決するための手段】本発明は上記目的を達成
するために、複数個の磁極を備えた移動体及び上記磁極
群の移動軌跡と対向配置された磁気センサを備えた磁気
式エンコーダにおいて、前記移動体の磁極を、磁気抵抗
が大なる磁気遮断部及び磁気抵抗が小なる磁気通路部を
当該移動体の移動方向に沿った状態で交互に有するマス
ク部材と、このマスク部材と一体的に設けられた永久磁
石とを備えた構成としたものである。
In order to achieve the above object, the present invention provides a magnetic encoder having a moving body having a plurality of magnetic poles and a magnetic sensor arranged so as to face the movement locus of the magnetic pole group. A mask member having alternating magnetic poles of the moving body in a state in which a magnetic blocking portion having a large magnetic resistance and a magnetic path portion having a small magnetic resistance are arranged along the moving direction of the moving body; And a permanent magnet provided in the.

【0008】[0008]

【作用】磁気抵抗が大なる磁気遮断部及び磁気抵抗が小
なる磁気通路部を移動体の移動方向に沿った状態で交互
に有するマスク部材が設けられる結果、その移動体に
は、永久磁石からの磁界がその移動方向に沿って交互に
強弱変化する磁極が形成される。このように形成される
磁極のピッチを微細に設定する場合には、永久磁石の着
磁ピッチを微細に設定する必要はなく、マスク部材に設
ける磁気遮断部及び磁気通路部の配列ピッチを微細に設
定するだけで良くなる。従って、全体を小形化した場合
でも、磁極ピッチを微細に設定することが可能となっ
て、分解能の向上を実現できる。
As a result, the mask member having the magnetic interruption portion having the large magnetic resistance and the magnetic passage portion having the small magnetic resistance alternately provided along the moving direction of the moving body is provided. Of the magnetic field of which the strength of the magnetic field of the magnetic field alternately changes along the moving direction. When the pitch of the magnetic poles formed in this way is finely set, it is not necessary to finely set the magnetizing pitch of the permanent magnets, and the array pitch of the magnetic blocking portions and the magnetic passage portions provided on the mask member is finely set. Just set it up. Therefore, even when the entire size is reduced, the magnetic pole pitch can be set finely and the resolution can be improved.

【0009】[0009]

【実施例】以下、本発明をロータリエンコーダに適用し
た第1実施例について図1、図2を参照しながら説明す
る。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is applied to a rotary encoder will be described below with reference to FIGS.

【0010】図1において、移動体たる回転ディスク1
1は、軸11aを中心に回転するように設けられ、その
外周縁部には複数個の磁極12が後述する手段によって
環状に形成されている。磁気センサ13は、具体的には
示さないが、所定ピッチの蛇行形状の感磁パターンを有
した周知構成の磁気抵抗素子より成るもので、磁極12
の回転軌跡に対してその軸方向から近接対向するように
配置されている。
In FIG. 1, a rotary disk 1 as a moving body.
1 is provided so as to rotate around a shaft 11a, and a plurality of magnetic poles 12 are formed in an annular shape on the outer peripheral edge portion by means described later. Although not specifically shown, the magnetic sensor 13 is composed of a well-known magnetic resistance element having a meandering magnetic sensing pattern of a predetermined pitch, and the magnetic pole 12
Are arranged so as to closely face each other in the axial direction with respect to the rotation locus.

【0011】上記回転ディスク11は、図2にも示すよ
うに、円板状のマスク部材14と、このマスク部材14
の裏側に配置された円板状の永久磁石15とを一体化し
た構成となっている。
As shown in FIG. 2, the rotary disk 11 has a disc-shaped mask member 14 and the mask member 14.
The disk-shaped permanent magnet 15 arranged on the back side of the is integrated.

【0012】この場合、永久磁石15は、その軸方向に
単極着磁され、以て表裏に異なる極性の一対の磁極を備
えた構成となっている。また、マスク部材14は、軟質
磁性体より成るもので、その外周縁部には、複数個のス
リット14aが所定ピッチ(前記磁気センサ13の感磁
パターンのピッチと同一ピッチ若しくは整数倍ピッチ)
にて環状配置となるように形成されている。これによ
り、マスク部材14には、磁気抵抗が大なる磁気遮断部
としてのスリット14aと磁気抵抗が小なる磁気通路部
14b(各スリット14a間の部分)とが、回転ディス
ク11の回転方向に沿った状態で交互に形成されること
になる。このようにして回転ディスク11の外周縁部
に、永久磁石15からの磁界がその移動方向に沿って交
互に強弱変化する磁極12が形成されるものである。
尚、上記スリット14aは、所謂ホト・エッチング・プ
ロセスにより形成される。
In this case, the permanent magnet 15 is magnetized in a single pole in the axial direction, and thus has a pair of magnetic poles of different polarities on the front and back sides. Further, the mask member 14 is made of a soft magnetic material, and a plurality of slits 14a are formed at a predetermined pitch (the same pitch as the magnetic sensitive pattern pitch of the magnetic sensor 13 or an integral multiple pitch) on the outer peripheral edge thereof.
Are formed so as to have an annular arrangement. As a result, the mask member 14 has a slit 14a as a magnetic blocking portion having a large magnetic resistance and a magnetic passage portion 14b having a small magnetic resistance (a portion between the slits 14a) along the rotation direction of the rotating disk 11. It will be formed alternately in the closed state. In this way, the magnetic poles 12 are formed on the outer peripheral edge of the rotating disk 11 so that the magnetic field from the permanent magnets 15 alternately changes in strength along the moving direction thereof.
The slit 14a is formed by a so-called photo etching process.

【0013】以上のような構成においては、回転ディス
ク11が回転すると、磁極12から磁気センサ13に作
用する磁界が周期的に変化するようになり、磁気センサ
13からは、磁極12の配列ピッチに応じて変化する検
知信号が出力されることになる。
In the above structure, when the rotary disk 11 rotates, the magnetic field acting on the magnetic sensor 13 from the magnetic pole 12 changes periodically, and the magnetic sensor 13 changes the arrangement pitch of the magnetic poles 12. A detection signal that changes accordingly is output.

【0014】上記した本実施例によれば、磁極12のピ
ッチを微細に設定する場合には、永久磁石15の着磁ピ
ッチを微細に設定する必要は全くなく、マスク部材14
に設けるスリット14aの配列ピッチを微細に設定する
だけで良くなる。この場合、上記スリット14aは、ホ
ト・エッチング・プロセスにより形成されるものである
から、その配列ピッチひいては磁極12のピッチを正確
且つ微細に設定することが可能となり、出力信号の分解
能の向上を実現できるようになる。
According to the present embodiment described above, when the pitch of the magnetic poles 12 is set finely, it is not necessary to set the magnetization pitch of the permanent magnets 15 finely, and the mask member 14 is used.
It suffices to set the arrangement pitch of the slits 14a provided in the above minutely. In this case, since the slits 14a are formed by the photo etching process, it is possible to accurately and finely set the array pitch, and thus the pitch of the magnetic poles 12, and to improve the resolution of the output signal. become able to.

【0015】図3には、上記第1実施例と同様の作用効
果を奏する本発明の第2実施例が示されており、以下こ
れについて異なる部分のみ説明する。
FIG. 3 shows a second embodiment of the present invention which has the same effects as the first embodiment, and only the different parts will be described below.

【0016】図3において、移動体たる回転ドラム16
は、軸16aを中心に回転するように設けられ、その外
周端面部には複数個の磁極17が一列状に形成されてお
り、磁気センサ13は、上記磁極17の回転軌跡に対し
てその径方向から近接対向するように配置されている。
In FIG. 3, a rotary drum 16 which is a moving body.
Are provided so as to rotate about a shaft 16a, and a plurality of magnetic poles 17 are formed in a line on the outer peripheral end face portion thereof. The magnetic sensor 13 has a diameter relative to the rotation locus of the magnetic pole 17. It is arranged so as to closely face and oppose from the direction.

【0017】回転ドラム16は、円板状の永久磁石18
と、この永久磁石18の外周端面部にこれを1周するよ
うに配置された環状のマスク部材19とを一体化した構
成となっている。この場合、永久磁石18は、その外周
端面部に同一の極性が現れるように単極着磁され、ま
た、マスク部材19は、軟質磁性体より成るもので、こ
れには、磁気遮断部としての複数個のスリット19a及
びこれらスリット19a間に位置した磁気通路部19b
を所定ピッチで形成することによって、永久磁石18か
らの磁界がその移動方向に沿って交互に強弱変化する磁
極17が形成されるものである。
The rotary drum 16 includes a disk-shaped permanent magnet 18
And an annular mask member 19 arranged around the outer peripheral end surface of the permanent magnet 18 so as to make one round. In this case, the permanent magnet 18 is unipolarly magnetized so that the same polarity appears on the outer peripheral end face portion thereof, and the mask member 19 is made of a soft magnetic material. A plurality of slits 19a and a magnetic path portion 19b located between these slits 19a
Are formed at a predetermined pitch to form the magnetic poles 17 in which the magnetic field from the permanent magnets 18 alternately changes in strength along the moving direction thereof.

【0018】尚、上記した各実施例では、軟質磁性体に
より形成したマスク部材14、19のスリット14a、
19aをホト・エッチング・プロセスにより形成する構
成としたが、これに限られるものではなく、微細な加工
が可能な手段であれば、プレス打ち抜き、レーザ加工に
よるダイレクトカットなどの手段を用いても良いもので
ある。また、例えばマスク部材としてプラスチック製シ
ートを設け、このシート上に磁性体製薄膜を印刷するこ
とによって、磁気抵抗が大なる磁気遮断部及び磁気抵抗
が小なる磁気通路部を交互に形成する構成とすることも
できる。さらに、永久磁石15、18は、必ずしも単極
着磁とする必要はなく、適宜の極数に着磁すれば良いも
のである。
In each of the above-mentioned embodiments, the slits 14a of the mask members 14 and 19 formed of a soft magnetic material,
Although 19a is formed by a photo etching process, the invention is not limited to this, and means such as press punching and direct cutting by laser processing may be used as long as it can perform fine processing. It is a thing. Further, for example, a plastic sheet is provided as a mask member, and a magnetic thin film is printed on the sheet to alternately form magnetic blocking portions having large magnetic resistance and magnetic passage portions having small magnetic resistance. You can also do it. Furthermore, the permanent magnets 15 and 18 do not necessarily need to be magnetized with a single pole, but may be magnetized with an appropriate number of poles.

【0019】その他、本発明は上記した各実施例に限定
されるものではなく、例えば磁気式リニアエンコーダに
適用しても良い等、その要旨を逸脱しない範囲で種々変
形して実施することができる。
In addition, the present invention is not limited to the above-described embodiments, but may be applied to a magnetic linear encoder, for example, and various modifications may be made without departing from the scope of the invention. ..

【0020】[0020]

【発明の効果】本発明によれば以上の説明によって明ら
かなように、移動体の磁極を、磁気抵抗が大なる磁気遮
断部及び磁気抵抗が小なる磁気通路部を当該移動体の移
動方向に沿った状態で交互に有するマスク部材と、この
マスク部材と一体的に設けられた永久磁石とを備えた構
成としたので、全体を小形化した場合でも磁極ピッチを
微細に設定することが可能になり、以て出力信号の分解
能を十分に向上させ得るという優れた効果を奏するもの
である。
According to the present invention, as is clear from the above description, the magnetic poles of the moving body are provided with the magnetic interruption portion having a large magnetic resistance and the magnetic passage portion having a small magnetic resistance in the moving direction of the moving body. Since the mask member and the permanent magnet that are provided integrally with the mask member are provided alternately along each other, the magnetic pole pitch can be set finely even when the entire size is reduced. Therefore, the excellent effect that the resolution of the output signal can be sufficiently improved is exhibited.

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

【図1】本発明の第1実施例を示す斜視図FIG. 1 is a perspective view showing a first embodiment of the present invention.

【図2】要部を分解した状態で示す斜視図FIG. 2 is a perspective view showing a main part in an exploded state.

【図3】本発明の第2実施例を示す斜視図FIG. 3 is a perspective view showing a second embodiment of the present invention.

【図4】従来例を示す斜視図FIG. 4 is a perspective view showing a conventional example.

【符号の説明】[Explanation of symbols]

図中、11は回転ディスク(移動体)、12は磁極、1
3は磁気センサ、14はマスク部材、14aはスリット
(磁気遮断部)、14bは磁気通路部、15は永久磁
石、16は回転ドラム(移動体)、17は磁極、18は
永久磁石、19はマスク部材、19aはスリット(磁気
遮断部)、19bは磁気通路部を示す。
In the figure, 11 is a rotating disk (moving body), 12 is a magnetic pole, 1
3 is a magnetic sensor, 14 is a mask member, 14a is a slit (magnetic blocking part), 14b is a magnetic passage part, 15 is a permanent magnet, 16 is a rotating drum (moving body), 17 is a magnetic pole, 18 is a permanent magnet, and 19 is A mask member, 19a is a slit (magnetic blocking portion), and 19b is a magnetic passage portion.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 複数個の磁極を備えた移動体と、前記磁
極群の移動軌跡と対向するように配置された磁気センサ
とを備えた磁気式エンコーダにおいて、前記移動体の磁
極を、磁気抵抗が大なる磁気遮断部及び磁気抵抗が小な
る磁気通路部を当該移動体の移動方向に沿った状態で交
互に有するマスク部材と、このマスク部材と一体的に設
けられた永久磁石とを備えた構成としたことを特徴とす
る磁気式エンコーダ。
1. A magnetic encoder comprising: a moving body having a plurality of magnetic poles; and a magnetic sensor arranged so as to face a movement locus of the magnetic pole group. A mask member that alternately has a large magnetic blocking portion and a magnetic passage portion that has a small magnetic resistance in a state along the moving direction of the moving body, and a permanent magnet integrally provided with the mask member. A magnetic encoder characterized by being configured.
JP21694291A 1991-08-28 1991-08-28 Magnetic encoder Pending JPH0552584A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP21694291A JPH0552584A (en) 1991-08-28 1991-08-28 Magnetic encoder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP21694291A JPH0552584A (en) 1991-08-28 1991-08-28 Magnetic encoder

Publications (1)

Publication Number Publication Date
JPH0552584A true JPH0552584A (en) 1993-03-02

Family

ID=16696351

Family Applications (1)

Application Number Title Priority Date Filing Date
JP21694291A Pending JPH0552584A (en) 1991-08-28 1991-08-28 Magnetic encoder

Country Status (1)

Country Link
JP (1) JPH0552584A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6160499A (en) * 1997-04-16 2000-12-12 Kabushiki Kaisha Yaskawa Denki Magnetic encoder apparatus
JP2013238485A (en) * 2012-05-15 2013-11-28 Asahi Kasei Electronics Co Ltd Encoder and actuator using the same
WO2013176104A1 (en) * 2012-05-22 2013-11-28 三菱電機株式会社 Magnetic rotation angle detector
WO2017206496A1 (en) * 2016-06-01 2017-12-07 江苏森尼克电子科技有限公司 Magnetic encoder and magnetic conductive code disc thereof, and manufacturing method for magnetic conductive code disc
DE102019112423A1 (en) * 2019-05-13 2020-11-19 RUAG Space Germany GmbH ENCODER

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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