JPH01202669A - Magnetic differential type tachometer - Google Patents
Magnetic differential type tachometerInfo
- Publication number
- JPH01202669A JPH01202669A JP2787788A JP2787788A JPH01202669A JP H01202669 A JPH01202669 A JP H01202669A JP 2787788 A JP2787788 A JP 2787788A JP 2787788 A JP2787788 A JP 2787788A JP H01202669 A JPH01202669 A JP H01202669A
- Authority
- JP
- Japan
- Prior art keywords
- teeth
- rotor
- stator
- magnetic
- stators
- 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
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 60
- 239000011295 pitch Substances 0.000 claims description 15
- 230000004907 flux Effects 0.000 claims description 14
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 238000001514 detection method Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 9
- 239000010409 thin film Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 2
- 230000000644 propagated effect Effects 0.000 description 2
- 239000003302 ferromagnetic material Substances 0.000 description 1
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- Transmission And Conversion Of Sensor Element Output (AREA)
Abstract
Description
【発明の詳細な説明】
〔概 要〕
回転数に対応した磁気的変化を検出する磁気差動型回転
計に関し、
低速から高速まで広範囲にわたって変化する車輪の回転
数を、高精度で検出すると共に安定した信号を出力でき
る回転計の提供を目的とし、永久磁石が内挿され回転軸
方向に磁化された回転子と、回転子のＮ極から出た磁束
をＳ極に戻すようにその外周に配置され、回転子と磁気
的に結合された一対の半円弧状固定子と、対向する固定
子９間に嵌挿された１乃至２個の磁電変換素子からなり
、少なくとも回転子の一方の磁極側に等ピンチで多数個
の外歯を形成すると共に、一対の固定子にそれぞれ外歯
と対向する多数個の内歯を形成し、且つ一方の固定子に
形成された内歯が外歯と対向した時に、他方の固定子に
形成された内歯が外歯と半ピンチずれるように構成する
。[Detailed Description of the Invention] [Summary] Regarding a magnetic differential type tachometer that detects magnetic changes corresponding to the rotation speed, the present invention relates to a magnetic differential type tachometer that detects magnetic changes corresponding to the rotation speed. The aim is to provide a tachometer that can output a stable signal.The rotor has a permanent magnet inserted in it and is magnetized in the direction of the rotating shaft, and a magnet is placed on the outer periphery of the rotor so that the magnetic flux emitted from the north pole of the rotor is returned to the south pole. Consisting of a pair of semicircular arc-shaped stators arranged and magnetically coupled to the rotor, and one or two magnetoelectric transducers inserted between the opposing stators 9, at least one magnetic pole of the rotor A large number of external teeth are formed on the sides with equal pinches, and a large number of internal teeth are formed on each of the pair of stators, each facing the external teeth, and the internal teeth formed on one stator are connected to the external teeth. When facing each other, the internal teeth formed on the other stator are configured to be shifted by half a pinch from the external teeth.
本発明は自動車等に組み込み回転数を検知するセンサに
係り、特に回転数に対応した磁気的変化を検出する磁気
差動型回転計に関する。The present invention relates to a sensor installed in an automobile or the like to detect rotation speed, and more particularly to a magnetic differential type tachometer that detects magnetic changes corresponding to rotation speed.
近年、モートロニクス技術の進歩に伴って操作を一層容
易にするため、制御系に各種のセンサやコンピュータを
組み込んだ自動車が実用化されている。かかる用途に用
いられる例えば走行速度計は従来のものと異なり、低速
から高速まで広範囲にわたって変化する車輪の回転数を
、高精度で検出すると共に安定した信号を出力できるこ
とが要求される。そこで最新のエレクトロニクス技術を
応用した各種センサが開発されている。In recent years, with advances in motorronics technology, automobiles have been put into practical use that incorporate various sensors and computers into their control systems in order to make operations easier. For example, traveling speedometers used in such applications are different from conventional ones and are required to be able to detect wheel rotation speeds that vary over a wide range from low speeds to high speeds with high precision and to output stable signals. Therefore, various sensors that apply the latest electronics technology are being developed.
第５図は従来の溝付回転子型回転計の原理を示す図、第
６図は従来の着磁回転子型回転計の原理を示す図である
。FIG. 5 is a diagram showing the principle of a conventional grooved rotor type tachometer, and FIG. 6 is a diagram showing the principle of a conventional magnetized rotor type tachometer.
第５図（ａ）に示す従来の溝付回転子型回転計は回転子
１とそれに対向するセンサ部２からなり、強磁性体を用
いて形成された回転子１はその周囲に、ピッチの等しい
多数個（例えば７２個）の溝１１を具えている。またセ
ンサ部２は強磁性体からなるヨーク２１と永久磁石２２
とセンスコイル２３とで構成され、回転子１に対向する
ヨーク２１の先端には溝１１と幅の等しい溝２４が形成
されている。The conventional grooved rotor type tachometer shown in FIG. 5(a) consists of a rotor 1 and a sensor section 2 facing it. An equal number of grooves 11 (for example, 72 grooves) are provided. Furthermore, the sensor section 2 includes a yoke 21 made of a ferromagnetic material and a permanent magnet 22.
and a sense coil 23, and a groove 24 having the same width as the groove 11 is formed at the tip of the yoke 21 facing the rotor 1.
回転子１が回転して溝１１が溝２４と対向する位置に来
た時と溝２４から外れた時とで、永久磁石２２から出て
ヨーク２１の内部を伝播する磁束が変化し、第５図世）
に示す如く磁束の変化即ち回転子の回転速度に対応した
交流電圧が、ヨーク２１または永久磁石２２に巻回され
たセンスコイル２３に発生する。When the rotor 1 rotates and the groove 11 comes to a position facing the groove 24 and when it comes out of the groove 24, the magnetic flux that comes out of the permanent magnet 22 and propagates inside the yoke 21 changes, and the fifth world)
As shown in FIG. 2, an alternating current voltage corresponding to the change in magnetic flux, that is, the rotational speed of the rotor, is generated in the sense coil 23 wound around the yoke 21 or the permanent magnet 22.
同図において実線は高速回転時を示し破線は低速回転時
を示す。In the figure, solid lines indicate high-speed rotation, and broken lines indicate low-speed rotation.
一方第６図（ａ）に示す従来の着磁回転子型回転計は回
転子３とセンサ部４からなり、回転子３として用いられ
ているリング状の永久磁石は、円周に沿ってＮ極とＳ極
が交互に並ぶように着磁されている。また回転子３に対
向しその磁界を検出するセンサ部４として、ブリッジ状
の磁気抵抗素子４１を含むハイブリッドＩＣが用いられ
ている。On the other hand, the conventional magnetized rotor type tachometer shown in FIG. It is magnetized so that the poles and S poles are arranged alternately. A hybrid IC including a bridge-shaped magnetoresistive element 41 is used as a sensor section 4 that faces the rotor 3 and detects its magnetic field.
第６図世）はかかる着磁回転子型回転計の動作を説明す
るための図で、■に示す如く回転子３の回転に伴ってＮ
極とＳ極が交互にセンサ部を通過し、それに対応した信
号■が磁気抵抗素子４１から出力される。磁気抵抗素子
４１の出力信号は比較器４２においてパルス信号■に変
換され、磁界の変化即ち回転子の回転速度に対応したパ
ルス信号■が出力端子４３から出力される。Figure 6) is a diagram for explaining the operation of such a magnetized rotor type tachometer.
The poles and the S poles alternately pass through the sensor section, and a corresponding signal (2) is output from the magnetoresistive element 41. The output signal of the magnetoresistive element 41 is converted into a pulse signal (2) by a comparator 42, and the pulse signal (2) corresponding to a change in the magnetic field, that is, the rotational speed of the rotor is outputted from an output terminal 43.
従来の溝付回転子型回転計は構成が簡単で信頼性が高く
、センスコイルの巻数を増大させることによって増幅器
が無くても大出力が得られる。しかし出力電圧が磁束の
変化量に比例するため低速回転時の出力電圧が小さ（、
例えば５１ｖ／ｈ以下の速度が検出できないという問題
があった。The conventional grooved rotor type tachometer has a simple structure and high reliability, and by increasing the number of turns of the sense coil, a large output can be obtained without an amplifier. However, since the output voltage is proportional to the amount of change in magnetic flux, the output voltage at low speed rotation is small (,
For example, there was a problem that speeds below 51 v/h could not be detected.
一方従来の着磁回転子型回転計は回転数に関係なく出力
電圧が得られ、低速から高速まで広範囲にわたって変化
する車輪の回転数を、高精度で検出すると共に安定した
信号を出力できるが、円周に沿ってＮ極とＳ極が交互に
配列されたリング状の永久磁石は着磁が困難で、しかも
分解能を高めるには細密ピッチでＮ極とＳ極を配列する
必要があり、着磁が益々困難になって高価になるという
問題があった。On the other hand, conventional magnetized rotor type tachometers can obtain an output voltage regardless of the rotation speed, and can detect the wheel rotation speed, which changes over a wide range from low speed to high speed, with high precision and output a stable signal. Ring-shaped permanent magnets with north and south poles arranged alternately along the circumference are difficult to magnetize, and in order to improve resolution it is necessary to arrange the north and south poles at a fine pitch. The problem was that magnets were becoming increasingly difficult and expensive.
第１図は本発明になる磁気差動型回転計の原理を示す斜
視図である。なお全図を通し同じ対象物は同一記号で表
している。FIG. 1 is a perspective view showing the principle of a magnetic differential type tachometer according to the present invention. The same objects are represented by the same symbols throughout the figures.
上記課題は永久磁石５１が内挿され回転軸方向に磁化さ
れた回転子５と、回転子５のＮ極から出た磁束をＳ極に
戻すようにその外周に配置され、回転子５と磁気的に結
合された一対の半円弧状固定子６と、対向する固定子６
の間に嵌挿された１乃至２個の磁電変換素子７からなり
、少なくとも回転子５の一方の磁極側に等ピッチで多数
個の外歯５２を形成すると共に、一対の固定子６にそれ
ぞれ外歯５２と対向する多数個の内歯６１を形成し、且
つ一方の固定子６に形成された内歯６１が外歯５２と対
向した時に、他方の固定子６に形成された内歯６１が外
歯５２と半ピッチずれるように、構成されてなる本発明
の磁気差動型回転計によって解決される。The above problem is solved by the rotor 5 having a permanent magnet 51 inserted therein and magnetized in the direction of the rotation axis, and the permanent magnet 51 being placed on the outer periphery of the rotor 5 so as to return the magnetic flux emitted from the north pole of the rotor 5 to the south pole. A pair of semicircular arc-shaped stators 6 coupled together and opposing stators 6
A large number of external teeth 52 are formed at equal pitches on at least one magnetic pole side of the rotor 5, and a plurality of external teeth 52 are formed on each of the pair of stators 6. A large number of internal teeth 61 are formed facing the external teeth 52, and when the internal teeth 61 formed on one stator 6 are opposed to the external teeth 52, the internal teeth 61 formed on the other stator 6 are This problem is solved by the magnetic differential type tachometer of the present invention, which is configured such that the outer teeth 52 are shifted by half a pitch.
第１図において永久磁石が内挿され回転軸方向に磁化さ
れた回転子と、回転子のＮ極から出た磁束をＳ極に戻す
ようにその外周に配置され、回転子と磁気的に結合され
た一対の半円弧状固定子と、対向する固定子の間に嵌挿
された１乃至２個の磁電変換素子からなり、少なくとも
回転子の一方の磁極側に等ピッチで多数個の外歯を形成
すると共に、一対の固定子゛にそれぞれ外歯と対向する
多数個の内歯を形成し、且つ一方の固定子に形成された
内歯が外歯と対向した時に、他方の固定子に形成された
内歯が外歯と半ピッチずれるよう構成することによって
、低速から高速まで広範囲にわたって変化する車輪の回
転数を、高精度で検出すると共に安定した信号を出力で
きる着磁回転子型回転計の長所と、構成が簡単で溝のピ
ンチを細分化することにより分解能を高めることのでき
る、比較的安価な溝付回転子型回転計の長所を兼ね具え
た回転計を実現することができる。In Figure 1, a permanent magnet is inserted and magnetized in the direction of the rotation axis, and a permanent magnet is placed on the outer periphery of the rotor so as to return the magnetic flux emitted from the north pole to the south pole, and is magnetically coupled to the rotor. It consists of a pair of semicircular arc-shaped stators and one or two magnetoelectric transducers inserted between the opposing stators, and a large number of external teeth are arranged at equal pitches on at least one magnetic pole side of the rotor. At the same time, a plurality of internal teeth facing the external teeth are formed on each of the pair of stators, and when the internal teeth formed on one stator face the external teeth, the other stator By configuring the formed internal teeth to be offset by half a pitch from the external teeth, a magnetized rotor-type rotation can detect the wheel rotation speed, which varies over a wide range from low speed to high speed, with high precision and output a stable signal. It is possible to realize a tachometer that combines the advantages of a relatively inexpensive grooved rotor type tachometer, which has a simple configuration and can improve resolution by dividing the pinch of the groove into smaller pieces. .
以下添付図により本発明の実施例について詳細社説明す
る。第２図は本発明の原理における動作の説明図、第３
図は本発明の実施例を示す斜視図、第４図は実施例にお
ける動作の説明図である。Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Figure 2 is an explanatory diagram of the operation according to the principle of the present invention, Figure 3
The figure is a perspective view showing an embodiment of the present invention, and FIG. 4 is an explanatory diagram of the operation in the embodiment.
第２図（ａｌは本発明になる回転計の原理を示す模式図
で、簡略化のためそれぞれの構成部品における内部抵抗
を無視し、回転子５と固定子６との間の磁気抵抗をＲ１
、Ｒ２、固定子６とＳ極との間の磁気抵抗をそれぞれＲ
３とすると、その磁気回路は第２図（ｂ）に示す等価回
路で表すことができる。FIG. 2 (al is a schematic diagram showing the principle of the tachometer according to the present invention. For simplicity, the internal resistance in each component is ignored, and the magnetic resistance between the rotor 5 and stator 6 is R1.
, R2, the magnetic resistance between the stator 6 and the S pole is R
3, the magnetic circuit can be represented by the equivalent circuit shown in FIG. 2(b).
図において回転子５の外歯が左側の固定子６の内歯と対
向している時、回転子５と左側の固定子６との間の磁気
抵抗Ｒ１は最小になり、回転子５の外歯が右側の固定子
６の内歯と半ピッチずれていて、回転子５と右側の固定
子６との間の磁気抵抗Ｒ２は最大になる０図示省略され
ているか外歯が移動し右側の固定子６の内歯と対向して
いる時、その外歯が左側の固定子６の内歯と半ピンチず
れているため、磁気抵抗Ｒ１は最大になり磁気抵抗Ｒ２
は最小になる。In the figure, when the external teeth of the rotor 5 are opposed to the internal teeth of the left stator 6, the magnetic resistance R1 between the rotor 5 and the left stator 6 is minimum, and the external teeth of the rotor 5 are opposite to the internal teeth of the left stator 6. The teeth are shifted by half a pitch from the internal teeth of the right stator 6, and the magnetic resistance R2 between the rotor 5 and the right stator 6 becomes maximum 0. When facing the internal teeth of the stator 6, the external teeth are shifted by half a pinch from the internal teeth of the left stator 6, so the magnetic resistance R1 becomes maximum and the magnetic resistance R2
becomes the minimum.
即ち可変抵抗器の摺動子が回転子５の移動に伴って、点
ａと点すの間を絶えず往復していると見なすことができ
、摺動子が点ａに位置するときは点Ｃにおける電位が点
ｄに比べて高く、摺動子が点すに位置するときは点ｄに
おける電位が点Ｃに比べて高（なる。In other words, the slider of the variable resistor can be considered to be constantly reciprocating between point a and point C as the rotor 5 moves, and when the slider is located at point a, it is at point C. The potential at point d is higher than point d, and when the slider is located at point d, the potential at point d is higher than point C.
この電位差に相当する磁位差が磁気抵抗素子等の磁電変
換素子７で検出され、外歯が左側の固定子６の内歯と対
向している時に磁電変換素子７から、例えば第２図（Ｃ
）に示す如く正電位の信号が出力されるものとすると、
外歯が右側の固定子６の内歯と対向している時は負電位
の信号が出力される。かかる出力信号の電圧は固定子間
の磁界の大きさにより決まり、回転子の移動速度、即ち
回転数によって変動することは無い。A magnetic potential difference corresponding to this potential difference is detected by a magnetoelectric transducer 7 such as a magnetoresistive element, and when the outer tooth is facing the inner tooth of the left stator 6, a magnetic potential difference corresponding to this potential difference is detected by the magnetoelectric transducer 7, for example, as shown in FIG. C
) Assuming that a positive potential signal is output as shown in
When the external teeth are opposed to the internal teeth of the right stator 6, a negative potential signal is output. The voltage of this output signal is determined by the magnitude of the magnetic field between the stators, and does not vary with the moving speed of the rotor, ie, the rotational speed.
なお１個の磁電変換素子７を対向する固定子の一方の隙
間に装着し、磁位差を検出することは可能であるが磁気
的ノイズの影響を受けやすい。かかる場合は磁電変換素
子７を対向する固定子の両方の隙間にそれぞれ装着し、
２個の磁電変換素子７を差動的に動作させることによっ
て磁気的ノイズを排除することができる。Although it is possible to install one magnetoelectric conversion element 7 in a gap between opposing stators and detect the difference in magnetic potential, it is susceptible to magnetic noise. In such a case, the magnetoelectric transducer 7 is installed in each gap between the opposing stators,
Magnetic noise can be eliminated by differentially operating the two magnetoelectric conversion elements 7.
第３図は本発明の一実施例で回転子５の一方の磁極側に
外歯５２が形成されており、他方の磁極側に外歯５２に
対し半ピッチずれた外歯５３が形成されている。一対の
固定子６には外歯５２．５３と対向し得る内歯６２がそ
れぞれ形成されており、一方の固定子６に形成された内
歯６２が外歯５２と対向した時に、他方の固定子６に形
成された内歯６２が外歯５２と半ピッチずれ、一方の固
定子６に形成された内歯６２が外歯５３と対向した時に
、他方の固定子６に形成された内歯６２が外歯５３と半
ピッチずれるように構成されている。FIG. 3 shows an embodiment of the present invention in which external teeth 52 are formed on one magnetic pole side of the rotor 5, and external teeth 53 shifted by a half pitch from the external teeth 52 are formed on the other magnetic pole side. There is. The pair of stators 6 are each formed with internal teeth 62 that can oppose the external teeth 52 and 53, and when the internal teeth 62 formed on one stator 6 oppose the external teeth 52, the other stator When the internal teeth 62 formed on the child 6 are shifted by half a pitch from the external teeth 52 and the internal teeth 62 formed on one stator 6 face the external teeth 53, the internal teeth formed on the other stator 6 62 is configured to be shifted by a half pitch from the external teeth 53.
第４図（ａ）に示す如く左側の固定子６に形成された内
歯６２が外歯５２と対向し、右側の固定子６に形成され
た内歯６２が外歯５３と対向している場合、Ｎ極から出
た磁束は外歯５２から左側の固定子６に形成された内歯
６２を経由し、更に右側の固定子６に形成された内歯６
２と外歯５３を経てＳ極に戻る。As shown in FIG. 4(a), the internal teeth 62 formed on the left stator 6 face the external teeth 52, and the internal teeth 62 formed on the right stator 6 face the external teeth 53. In this case, the magnetic flux emitted from the N pole passes from the external teeth 52 to the internal teeth 62 formed on the left stator 6, and then to the internal teeth 6 formed on the right stator 6.
2 and the external tooth 53 to return to the S pole.
固定子５が移動し右側の固定子６に形成された内歯６２
が外歯５２と対向し、左側の固定子６に形成された内歯
６２が外歯５３と対向している場合、Ｎ極から出た磁束
は外歯５２から右側の固定子６に形成された内歯６２を
経由し、更に左側の固定子６に形成された内歯６２と外
歯５３を経てＳ極に戻る。When the stator 5 moves, the internal teeth 62 formed on the right stator 6
If the inner teeth 62 formed on the left stator 6 face the outer teeth 53, the magnetic flux emitted from the N pole is formed from the outer teeth 52 to the right stator 6. It returns to the S pole via the internal teeth 62 formed on the left side stator 6, and further via the internal teeth 62 and external teeth 53 formed on the left stator 6.
このように固定子５が半ピッチ移動する毎に磁束の方向
を、図の左上から右下へ、或いは右上から左下へ矢示の
如く変化させる方法は、磁電変換素子７としてバーバー
ポール型の磁気抵抗素子を用いる場合に特に有効である
。In this way, the direction of the magnetic flux is changed from the upper left to the lower right in the figure, or from the upper right to the lower left as shown by the arrows, every time the stator 5 moves by half a pitch. This is particularly effective when using a resistance element.
バーバーポール型の磁気抵抗素子は第４図（ｂ）に示す
如（、つづら折れ状のパターンを有するパーマロイ（Ｆ
ｅ−Ｎｉ）等からなる磁性薄膜７１と、その上に一定間
隔で斜めに付着形成されたＡｕ等の導電性薄膜７２から
なり、磁性薄膜７１は一軸異方性を与えるため矢印Ｍ方
向に予め磁化されている。図において磁束が左上から右
下に伝播される磁界はＨｅｘ方向のベクトルとＭ方向の
ベクトルを有し、磁束が右上から左下に伝播される磁界
は）Ｉｅｘと反対方向のベクトルとＭ方向のベクトルを
有する。The barber pole type magnetoresistive element is shown in Figure 4(b).
The magnetic thin film 71 consists of a magnetic thin film 71 made of e-Ni, etc., and a conductive thin film 72 of Au etc. deposited diagonally at regular intervals thereon. It is magnetized. In the figure, the magnetic field in which the magnetic flux is propagated from the upper left to the lower right has a vector in the Hex direction and a vector in the M direction, and the magnetic field in which the magnetic flux is propagated from the upper right to the lower left has a vector in the opposite direction to Iex and a vector in the M direction. has.
バーバーポール型の磁気抵抗素子はＨｅｘ方向の磁界が
印加された時に、第４図（Ｃ）に示す如く正方向の電圧
が出力されるものとすると、逆方向の磁界が印加された
時に負方向の電圧が出力され、その際同時に矢印Ｍ方向
の磁界を印加すると破線で示す如く出力曲線の直線性が
改善される。即ち磁束の方向が左上から右下へ、或いは
右上から左下へ変化する上記実施例は、Ｍ方向のベクト
ルが常に印加されるため直線性の優れた出力信号を得る
ことができる。If a barber pole type magnetoresistive element outputs a voltage in the positive direction as shown in Figure 4 (C) when a magnetic field in the Hex direction is applied, then when a magnetic field in the opposite direction is applied, it outputs a voltage in the negative direction. If a magnetic field in the direction of arrow M is applied at the same time, the linearity of the output curve is improved as shown by the broken line. That is, in the embodiments described above in which the direction of the magnetic flux changes from the upper left to the lower right or from the upper right to the lower left, a vector in the M direction is always applied, so that an output signal with excellent linearity can be obtained.
このように永久磁石が内挿され回転軸方向に磁化された
回転子と、回転子のＮ極から出た磁束をＳ極に戻すよう
にその外周に配置され、回転子と磁気的に結合された一
対の半円弧状固定子と、対向する固定子の間に嵌挿され
た１乃至２個の磁電変換素子からなり、少なくとも回転
子の一方の磁極側に等ピッチで多数個の外歯を形成する
と共に、一対の固定子にそれぞれ外歯と対向する多数個
の内歯を形成し、且つ一方の固定子に形成された内歯が
外歯と対向した時に、他方の固定子に形成された内歯が
外歯と半ピッチずれるよう構成することによって、低速
から高速まで広範囲にわたって変化する車輪の回転数を
、高精度で検出すると共に安定した信号を出力できる着
磁回転子型回転計の長所と、構成が簡単で溝のピッチを
細分化することにより分解能を高めることのできる、比
較的安価な溝付回転子型回転計の長所を兼ね具えた回転
計を実現することができる。In this way, a permanent magnet is inserted into the rotor and magnetized in the direction of the rotation axis, and a permanent magnet is placed on the outer periphery of the rotor so as to return the magnetic flux emitted from the N pole of the rotor to the S pole, and is magnetically coupled to the rotor. It consists of a pair of semicircular arc-shaped stators and one or two magnetoelectric conversion elements inserted between the opposing stators, and a large number of external teeth are arranged at equal pitches on at least one magnetic pole side of the rotor. At the same time, a plurality of internal teeth facing the external teeth are formed on each of the pair of stators, and when the internal teeth formed on one stator face the external teeth, the internal teeth formed on the other stator are formed. By configuring the internal teeth to be offset by half a pitch from the external teeth, this magnetized rotor-type tachometer is capable of detecting the wheel rotation speed, which varies over a wide range from low to high speeds, with high precision and outputting a stable signal. It is possible to realize a tachometer that has the advantages of a relatively inexpensive grooved rotor type tachometer, which has a simple configuration and can improve resolution by subdividing the pitch of the grooves.
上述の如く本発明によれば低速から高速まで広範囲にわ
たって変化する車輪の回転数を、高精度で検出すると共
に安定した信号を出力できる磁気差動型回転計を提供す
ることができる。As described above, according to the present invention, it is possible to provide a magnetic differential tachometer that can accurately detect the rotational speed of a wheel, which varies over a wide range from low speed to high speed, and can output a stable signal.
第１図は本発明になる磁気差動型回転計の原理を示す斜
視図、
第２図は本発明の原理における動作の説明図、第３図は
本発明の実施例を示す斜視図、第４図は実施例における
動作の説明図、第５図は従来の溝付回転子型回転計の原
理を示す図、
第６図は従来の着磁回転子型回転計の原理を示す図、
である。図において
５は回転子、 ６は固定子、
７は磁電変換素子、 ５１は永久磁石、５２．５３は外
歯、 ６１．６２は内歯、７１は磁性薄膜、
７２は導電性薄膜、をそれぞれ表す。
（ｂ）
水金ｅ月り原Ｊ里にあけ５重力ｆ′Ｆ巧言之ｅＨ図ｊｈ
２ 図
（１）ン
（Ｇ）−＠ｅｘ
突先！９すに六ける重力作り説ヨ月ｐり第４ 図Fig. 1 is a perspective view showing the principle of the magnetic differential type tachometer according to the present invention, Fig. 2 is an explanatory view of the operation based on the principle of the present invention, and Fig. 3 is a perspective view showing an embodiment of the present invention. Figure 4 is an explanatory diagram of the operation in the embodiment, Figure 5 is a diagram illustrating the principle of a conventional grooved rotor type tachometer, and Figure 6 is a diagram illustrating the principle of a conventional magnetized rotor type tachometer. be. In the figure, 5 is a rotor, 6 is a stator, 7 is a magnetoelectric conversion element, 51 is a permanent magnet, 52.53 is an external tooth, 61.62 is an internal tooth, 71 is a magnetic thin film,
72 represents a conductive thin film. (b) Wednesday, Friday, month, day, day, day, day, day, day, day, day, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year, year and year.
2 Figure (1)
(G)-@ex tip! Figure 4
Claims (1)
転子（５）と、該回転子（５）のＮ極から出た磁束をＳ
極に戻すようにその外周に配置され、該回転子（５）と
磁気的に結合された一対の半円弧状固定子（６）と、対
向する該固定子（６）の間に嵌挿された１乃至２個の磁
電変換素子（７）からなり、少なくとも該回転子（５）
の一方の磁極側に等ピッチで多数個の外歯（５２）を形
成すると共に、一対の該固定子（６）にそれぞれ該外歯
（５２）と対向する多数個の内歯（６１）を形成し、且
つ一方の該固定子（６）に形成された該内歯（６１）が
該外歯（５２）と対向した時に、他方の該固定子（６）
に形成された該内歯（６１）が該外歯（５２）と半ピッ
チずれるように、構成されてなることを特徴とする磁気
差動型回転計。The rotor (5) has a permanent magnet (51) inserted therein and is magnetized in the direction of the rotation axis, and the magnetic flux emitted from the N pole of the rotor (5) is
A pair of semicircular arc-shaped stators (6) are arranged on the outer periphery so as to return to the poles and are magnetically coupled to the rotor (5), and the rotor (5) is fitted between the opposing stators (6). It consists of one or two magnetoelectric transducers (7), and at least the rotor (5)
A large number of external teeth (52) are formed at equal pitches on one magnetic pole side of the stator (6), and a large number of internal teeth (61) facing the external teeth (52) are formed on each of the pair of stators (6). and when the internal teeth (61) formed on one stator (6) face the external teeth (52), the other stator (6)
A magnetic differential type tachometer characterized in that the inner teeth (61) formed on the outer teeth (61) are deviated by a half pitch from the outer teeth (52).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2787788A JPH01202669A (en) | 1988-02-09 | 1988-02-09 | Magnetic differential type tachometer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2787788A JPH01202669A (en) | 1988-02-09 | 1988-02-09 | Magnetic differential type tachometer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01202669A true JPH01202669A (en) | 1989-08-15 |
Family
ID=12233122
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2787788A Pending JPH01202669A (en) | 1988-02-09 | 1988-02-09 | Magnetic differential type tachometer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01202669A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02141616A (en) * | 1988-11-24 | 1990-05-31 | Copal Co Ltd | Apparatus for detecting relative displacement |
-
1988
- 1988-02-09 JP JP2787788A patent/JPH01202669A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02141616A (en) * | 1988-11-24 | 1990-05-31 | Copal Co Ltd | Apparatus for detecting relative displacement |
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