JPH07332913A - Magnetic positional sensor - Google Patents
Magnetic positional sensorInfo
- Publication number
- JPH07332913A JPH07332913A JP13211894A JP13211894A JPH07332913A JP H07332913 A JPH07332913 A JP H07332913A JP 13211894 A JP13211894 A JP 13211894A JP 13211894 A JP13211894 A JP 13211894A JP H07332913 A JPH07332913 A JP H07332913A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- magnetic path
- coil
- coils
- path forming
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、直線移動あるいは回転
移動する可動部材の位置を検出できる磁気式位置センサ
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic position sensor capable of detecting the position of a movable member which moves linearly or rotationally.
【０００２】[0002]
【従来の技術】従来、かかる磁気式位置センサとして、
自動車等のスロットル開度を検出するスロットルポジシ
ョンセンサ（Throttle Position Senser）が知られてい
る。一例を示すと、例えば、特公昭５５−１３２８６及
び特公昭５５−９８１８に開示されているものがある。
これらは、可動磁心と固定磁心とが３つの対向部で結合
し、２つの閉回路を構成している。可動磁心の変位によ
り対向部面積が変化し、各閉磁路の磁気抵抗による各コ
イルのインダクタンス変化を検出して、可動磁心の位置
信号を検出するものである。2. Description of the Related Art Conventionally, as such a magnetic position sensor,
A throttle position sensor (Throttle Position Sensor) that detects a throttle opening degree of an automobile or the like is known. For example, there are those disclosed in Japanese Patent Publication No. 55-13286 and Japanese Patent Publication No. 55-9818.
In these, the movable magnetic core and the fixed magnetic core are coupled at three facing portions to form two closed circuits. The area of the facing portion changes due to the displacement of the movable magnetic core, and the change in the inductance of each coil due to the magnetic resistance of each closed magnetic circuit is detected to detect the position signal of the movable magnetic core.
【０００３】しかし、可動磁心と固定磁心で作られる２
つの閉回路は、対向部面積以外に、そのギャップ長の影
響を受けることになり、固定磁心が可動磁心に対して変
位する時に、両磁心のギャップ長を一定に維持するため
には、両磁心の対向面の平行度を高精度に製造する必要
があるため製造コストが高くなるという問題がある。ま
た、ホール素子を利用した磁気式位置センサがある。例
えば特開平５−２６６１０号公報に開示されているよう
なものである。However, it is made of a movable magnetic core and a fixed magnetic core.
The two closed circuits will be affected by the gap length in addition to the area of the facing part, and in order to keep the gap length of both cores constant when the fixed core is displaced with respect to the movable core, Since it is necessary to manufacture the facing surfaces in parallel with high precision, there is a problem that the manufacturing cost becomes high. There is also a magnetic position sensor that uses a Hall element. For example, it is as disclosed in Japanese Patent Laid-Open No. 5-26610.
【０００４】かかるセンサの構造は、スロットルバルブ
に連動して回転するスロットルシャフトと一体的に回動
するように、その回転面上に一対の永久磁石を対向配置
し、さらに、この一対の永久磁石間でスロットルシャフ
トの軸線上に一つのホール素子を配置したものとなって
いる。これによれば、一対の永久磁石がスロットルシャ
フトの回転軸を挟んで磁気回路を形成する。そして、そ
の形成された磁気回路の磁界方向は、スロットルシャフ
トの回転角度に応じて変化することになる。従って、か
かる一対の永久磁石間に設けられたホール素子を通過す
る磁束の変化を検出して、スロットルの開度を検出でき
るというものである。The structure of such a sensor is such that a pair of permanent magnets are arranged facing each other on the surface of rotation so as to rotate integrally with a throttle shaft that rotates in conjunction with a throttle valve. One Hall element is arranged on the axis of the throttle shaft between them. According to this, the pair of permanent magnets form a magnetic circuit with the rotary shaft of the throttle shaft interposed therebetween. Then, the magnetic field direction of the formed magnetic circuit changes according to the rotation angle of the throttle shaft. Therefore, the opening of the throttle can be detected by detecting the change in the magnetic flux passing through the Hall element provided between the pair of permanent magnets.
【０００５】また、シャフトの回転軸を中心とする円弧
上に沿って一対の円弧状永久磁石を並設し、これら円弧
状永久磁石から回転軸の軸線方向に離間した位置に一つ
のホール素子を配置して、かかる一対の円弧状永久磁石
によって形成される磁気回路の磁界の方向を検出するこ
とにより、アイドル運転状態を検出できるというもので
ある。Further, a pair of arc-shaped permanent magnets are arranged in parallel along an arc centered on the rotation axis of the shaft, and one Hall element is provided at a position separated from these arc-shaped permanent magnets in the axial direction of the rotation axis. By arranging and detecting the direction of the magnetic field of the magnetic circuit formed by the pair of arc-shaped permanent magnets, the idle operating state can be detected.
【０００６】これらの磁気式位置センサはいずれも、一
つの磁気回路内に一つのホール素子を配置して、かかる
磁気回路内の磁界の変化等を検出する構造となってい
る。しかし、磁気位置センサにホール素子等を用いる場
合には、その温度特性により出力ドリフトが生じるので
温度補償のための温度補償回路等が必要になるという欠
点がある。Each of these magnetic position sensors has a structure in which one Hall element is arranged in one magnetic circuit to detect changes in the magnetic field in the magnetic circuit. However, when a Hall element or the like is used for the magnetic position sensor, there is a disadvantage that a temperature compensating circuit or the like for temperature compensation is required because an output drift occurs due to its temperature characteristic.
【０００７】[0007]
【発明が解決しようとする課題】上記従来技術の問題点
等に鑑み、本願発明の目的とするところは、加工精度を
要求しない簡素な構成で、かつ耐久性があり、雰囲気温
度あるいはセンサを構成する磁性材料のインダクタンス
特性等の影響を受けることがなく、回動移動あるいは直
線移動等の変位位置を小規模な回路で高精度に検出でき
る磁気式位置センサを提供することにある。In view of the above-mentioned problems of the prior art, the object of the present invention is to provide a simple structure which does not require processing accuracy and is durable, and to configure an ambient temperature or a sensor. It is an object of the present invention to provide a magnetic position sensor that can detect a displacement position such as a rotational movement or a linear movement with high precision by a small-scale circuit without being affected by the inductance characteristic of the magnetic material.
【０００８】[0008]
【課題を解決するための手段】本発明の磁気式位置セン
サは、少なくとも１つの第１閉磁路を形成する第１の磁
路形成手段と、前記第１の磁路形成手段に対して非接触
で所定範囲に亘って相対的に移動可能であって前記第１
閉磁路を２つの閉磁路に分岐する分岐磁路を形成する第
２の磁路形成手段と、前記所定範囲を挟む位置にて前記
第１閉磁路に鎖交する２つの第１及び第２コイルと、前
記分岐磁路に鎖交する１つの第３コイルと、前記３つの
うち１つのコイルを交流励磁し、他の２つのコイルに発
生する起電力を検出して前記第２の磁路形成手段の位置
信号を発生する位置信号発生手段と、を有する磁気式位
置センサであって、前記位置信号発生手段は、前記他の
２つのコイルの検出起電力の加算値に応じて、前記１つ
のコイルに流れる励磁電流を制御し、前記他の２つのコ
イルの少なくとも一方の出力を検出出力とすることを特
徴とするものである。A magnetic position sensor according to the present invention comprises a first magnetic path forming means forming at least one first closed magnetic path, and a non-contact with the first magnetic path forming means. Is relatively movable over a predetermined range, and
Second magnetic path forming means for forming a branch magnetic path for branching the closed magnetic path into two closed magnetic paths, and two first and second coils interlinking with the first closed magnetic path at positions sandwiching the predetermined range. And one third coil interlinking with the branch magnetic path and one of the three coils are AC-excited, and electromotive force generated in the other two coils is detected to form the second magnetic path. A position signal generating means for generating a position signal of the means, the position signal generating means, wherein the position signal generating means corresponds to the one of the one of the other coils depending on an added value of the detected electromotive force of the other two coils. The exciting current flowing through the coil is controlled, and the output of at least one of the other two coils is used as a detection output.
【０００９】[0009]
【作用】このような特徴を有する本発明の磁気式位置セ
ンサによれば、センサ内に配置された３つのコイルの１
つを励磁し、第２の磁路形成手段の位置に対応した他の
２つのコイルに生じる起電力を検出する。その両検出出
力の加算値と基準値を比較して差信号を得る。かかる差
信号により前記１つのコイルを励磁する励磁電流を調整
することにより、前記他の２つのコイルの起電力の加算
値が常に一定になるように前記１つのコイルに流れる励
磁電流を制御するものである。また、他の２つのコイル
の起電力の加算値が常に一定であるので、第２の磁路形
成手段の位置は、一方のコイルの起電力に比例すること
になる。従って、１つのコイルの起電力を検出すること
により正確に第２の磁路形成手段の位置を検出すること
が可能となる。According to the magnetic position sensor of the present invention having such a feature, one of the three coils arranged in the sensor is used.
One of them is excited, and the electromotive force generated in the other two coils corresponding to the position of the second magnetic path forming means is detected. A difference signal is obtained by comparing the added value of both detection outputs with the reference value. By adjusting the exciting current that excites the one coil by such a difference signal, the exciting current flowing through the one coil is controlled so that the added value of the electromotive forces of the other two coils is always constant. Is. Further, since the added value of the electromotive forces of the other two coils is always constant, the position of the second magnetic path forming means is proportional to the electromotive force of one coil. Therefore, the position of the second magnetic path forming unit can be accurately detected by detecting the electromotive force of one coil.
【００１０】[0010]
【実施例】以下、本願発明に係わる磁気式位置センサの
実施例を第１図に示す。本図に示される実施例において
は、第１の磁路形成手段は、半円環状磁性部材１ａ及び
半円環状磁性部材１ａの両脚部間に架設された棒状磁性
部材１ｂとからなる。第２の磁路形成手段は、コイル４
が巻回された磁性部材７及び磁路部材５から構成されて
いる。磁性部材７及び磁路部材５は、半円環状磁性部材
１ａ及び棒状磁性部材１ｂによって囲まれる空間内に配
置されている。磁性部材７の一端は棒状磁性部材１ｂと
当接又は固着している。また、磁性部材７と棒状磁性部
材１ｂとは一体に成型されることも考えられる。磁路部
材５は回動シャフト６にネジ等の結合手段８により結合
されており、磁路部材５は回動シャフト６に担持されて
半円環状磁性部材１ａの半円周内で回動運動を行う。磁
性部材７の他端は磁路部材５の回転中心部と当接してい
る。半円環状磁性部材１ａの曲率半径よりも磁路部材５
の回動半径は小さく設定され、それら曲率の中心と回動
の中心とは一致している。また、半円環状磁性部材１ａ
には一対のコイル２、３が巻回配置されている。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a magnetic type position sensor according to the present invention is shown in FIG. In the embodiment shown in this figure, the first magnetic path forming means is composed of a semi-annular magnetic member 1a and a rod-shaped magnetic member 1b which is installed between both legs of the semi-annular magnetic member 1a. The second magnetic path forming means is the coil 4
Is composed of a magnetic member 7 and a magnetic path member 5 that are wound. The magnetic member 7 and the magnetic path member 5 are arranged in a space surrounded by the semi-annular magnetic member 1a and the rod-shaped magnetic member 1b. One end of the magnetic member 7 is in contact with or fixed to the rod-shaped magnetic member 1b. It is also conceivable that the magnetic member 7 and the rod-shaped magnetic member 1b are integrally molded. The magnetic path member 5 is connected to the rotating shaft 6 by a connecting means 8 such as a screw, and the magnetic path member 5 is carried by the rotating shaft 6 and is rotated within the semicircle of the semicircular magnetic member 1a. I do. The other end of the magnetic member 7 is in contact with the center of rotation of the magnetic path member 5. The magnetic path member 5 is larger than the radius of curvature of the semi-annular magnetic member 1a.
The turning radius of is set to be small, and the center of curvature and the center of turning match. Also, the semi-annular magnetic member 1a
A pair of coils 2 and 3 is wound around the coil.
【００１１】以上のような構成から成る磁気式位置セン
サによれば、コイル４を図示しない交流電源にて励磁す
るとコイル４からでた磁束は、磁路部材５を通り、磁路
部材５と半円環状磁性部材１ａとのギャップを通過して
半円環状磁性部材１ａに入り、２つの磁束に分岐されコ
イル２、３を夫々経由し、棒状磁性部材１ｂを通り、再
びコイル４に戻り２つの閉磁路を形成する。この磁束の
方向は励磁電流の方向に応じて変化する。このように２
分された閉磁路において、コイル２、３の出力電圧を検
出すれば磁路部材５の位置すなわち回転角度を検出する
ことができる。According to the magnetic position sensor having the above structure, when the coil 4 is excited by the AC power supply (not shown), the magnetic flux generated from the coil 4 passes through the magnetic path member 5 and the magnetic path member 5 It passes through the gap with the annular magnetic member 1a, enters the semi-annular magnetic member 1a, is branched into two magnetic fluxes, passes through the coils 2 and 3, respectively, passes through the rod-shaped magnetic member 1b, and returns to the coil 4 again. Form a closed magnetic circuit. The direction of this magnetic flux changes according to the direction of the exciting current. 2 like this
In the divided closed magnetic path, the position of the magnetic path member 5, that is, the rotation angle can be detected by detecting the output voltage of the coils 2 and 3.
【００１２】また、本実施例に係る磁気式位置センサの
具体的応用については、回動シャフトを例えば内燃機関
のスロットルバルブに連結することにより、スロットル
ポジションセンサを得ることができる。以上の実施例等
に係る磁気式位置センサは、さらに、自動工作機械、自
動搬送機械等における位置検出手段としても用いること
ができ、工場の自動化（ＦＡ）等においても好ましく適
用できるものである。Further, regarding a specific application of the magnetic position sensor according to this embodiment, a throttle position sensor can be obtained by connecting a rotating shaft to, for example, a throttle valve of an internal combustion engine. The magnetic position sensor according to the above-described embodiments and the like can be further used as a position detecting means in an automatic machine tool, an automatic carrier machine, or the like, and can be preferably applied to factory automation (FA) or the like.
【００１３】次に、上記した実施例等に係わる磁気式位
置センサの動作原理を図２の概念図に基づいて説明す
る。図１と同等部分は同一符号を付し、同一部材の説明
は省略する。図２において、磁束の流れを矢印で表す。
コイル４を図示しない交流電源にて励磁すると磁束が発
せられる。コイル４から発した磁束はギャップ９、磁路
部材５、及びギャップ１０を通過して半円環状磁性部材
１ａに入り磁束は２つに分岐され、コイル２、３を夫々
経由し、棒状磁性部材１ｂを通り、コイル４に再び戻
り、２つの閉磁路Ｓ１及びＳ２が夫々形成される。Next, the operation principle of the magnetic type position sensor according to the above-described embodiment will be described with reference to the conceptual diagram of FIG. The same parts as those in FIG. 1 are designated by the same reference numerals, and the description of the same members will be omitted. In FIG. 2, the flow of magnetic flux is represented by an arrow.
When the coil 4 is excited by an AC power supply (not shown), a magnetic flux is generated. The magnetic flux generated from the coil 4 passes through the gap 9, the magnetic path member 5, and the gap 10 and enters the semi-annular magnetic member 1a, and the magnetic flux is branched into two, passes through the coils 2 and 3, respectively, and passes through the rod-shaped magnetic member. After passing through 1b and returning to the coil 4, two closed magnetic paths S1 and S2 are formed respectively.
【００１４】この時、２つの閉磁路Ｓ１及びＳ２を通る
磁束の大きさは、磁路部材５の位置に応じて変化する。
例えば、磁路部材５がコイル３側に回転すればコイル３
に鎖交する磁束の大きさが増加し、その分コイル２に鎖
交する磁束の大きさが減少する。一方、磁路部材５がコ
イル２側に回転すれば、上記現象と逆の現象が生じるこ
とになる。At this time, the magnitude of the magnetic flux passing through the two closed magnetic paths S1 and S2 changes according to the position of the magnetic path member 5.
For example, if the magnetic path member 5 rotates to the coil 3 side, the coil 3
The magnitude of the magnetic flux linked to the coil 2 increases, and the magnitude of the magnetic flux linked to the coil 2 decreases accordingly. On the other hand, if the magnetic path member 5 rotates toward the coil 2, a phenomenon opposite to the above phenomenon will occur.
【００１５】従って、かかるコイル２、３の起電力を検
出することにより、磁性部材１に対する磁路部材５の位
置すなわち回転角を求めることができる。以下、この検
出原理を図２の概念図に基づいて詳述する。磁路部材５
の回動中心Ｏから半円環状磁性部材１ａに対し垂下した
線と半円環状磁性部材１ａとが交差する点をＣとする。
Ｏ−Ｃ線と磁路部材５とが為す角をα（ここで、αの単
位をラジアンとする）とする。半円環状磁性部材１ａ及
び棒状磁性部材１ｂにおいて磁束が通る全経路長を２Ｌ
とし、磁性部材７、磁路部材５の長さをＬ1、Ｌ2とし、
磁路部材５の回動半径をｒとし、磁束の通過する断面積
を全てＳとし、磁性部材７、磁路部材５の磁界の強さを
Ｈ0、Ｈ3とし、ギャップ９、１０の磁界の強さをＨ9、
Ｈ10とし、ギャップ９、１０の長さをＬ9、Ｌ10とし、
閉磁路Ｓ１、Ｓ２の磁界の強さを夫々Ｈ1、Ｈ2とし、コ
イル４で発生する起磁力をＮiとするとアンペアの周積
分の定理より閉磁路Ｓ１、Ｓ２には、それぞれ下記数式
１、数式２の関係がある。Therefore, by detecting the electromotive force of the coils 2 and 3, the position of the magnetic path member 5 with respect to the magnetic member 1, that is, the rotation angle can be obtained. Hereinafter, this detection principle will be described in detail based on the conceptual diagram of FIG. Magnetic path member 5
Let C be a point where a line hanging down from the rotation center O of the semicircular magnetic member 1a intersects the semicircular magnetic member 1a.
The angle formed by the OC line and the magnetic path member 5 is α (here, the unit of α is radian). In the semi-annular magnetic member 1a and the rod-shaped magnetic member 1b, the total path length through which the magnetic flux passes is 2L.
And the lengths of the magnetic member 7 and the magnetic path member 5 are L1 and L2,
Let r be the turning radius of the magnetic path member 5, S be all the cross-sectional areas through which the magnetic flux passes, the magnetic field strengths of the magnetic member 7 and the magnetic path member 5 be H0 and H3, and the magnetic field strengths of the gaps 9 and 10. H9,
H10 and the lengths of the gaps 9 and 10 are L9 and L10,
Assuming that the magnetic field strengths of the closed magnetic paths S1 and S2 are H1 and H2, respectively, and the magnetomotive force generated in the coil 4 is Ni, the closed magnetic paths S1 and S2 are respectively represented by the following formula 1 and formula 2 from the Ampere's circumferential integral theorem. Have a relationship.
【００１６】[0016]
【数１】Ｈ0・Ｌ1＋Ｈ9・Ｌ9＋Ｈ3・Ｌ2＋Ｈ10・Ｌ10＋
Ｈ1（Ｌ＋ｒ・α）＝Ｎi[Equation 1] H0 ・ L1 + H9 ・ L9 + H3 ・ L2 + H10 ・ L10 +
H1 (L + r ・ α) = Ni
【００１７】[0017]
【数２】Ｈ0・Ｌ1＋Ｈ9・Ｌ9＋Ｈ3・Ｌ2＋Ｈ10・Ｌ10＋
Ｈ2（Ｌ−ｒ・α）＝Ｎi 上記数式１及び２において、共通項を削除するために、
（上記数式１）−（上記数式２）なる演算をなし、その
結果をαについてまとめると下記数式３の関係が導き出
される。[Equation 2] H0 ・ L1 + H9 ・ L9 + H3 ・ L2 + H10 ・ L10 +
H2 (Lr.alpha.) = Ni In order to eliminate the common term in the above equations 1 and 2,
The relation of the following mathematical formula 3 is derived by performing the operation of (the above mathematical formula 1)-(the above mathematical formula 2) and summing up the results with respect to α.
【００１８】[0018]
【数３】 ここでＨ2＋Ｈ1＝const（constは定数）とすると下記数
式４が導出される。[Equation 3] Here, if H2 + H1 = const (const is a constant), the following Equation 4 is derived.
【００１９】[0019]
【数４】 コイル２、３に生じる交流電圧Ｖ1及びＶ2は、Ｈ1及び
Ｈ2に比例するので下記数式５が導かれる。[Equation 4] Since AC voltages V1 and V2 generated in the coils 2 and 3 are proportional to H1 and H2, the following formula 5 is derived.
【００２０】[0020]
【数５】 ここで、上記数式５をαについて整理すると、下記数式
６が導かれる。[Equation 5] Here, by rearranging the above Equation 5 with respect to α, the following Equation 6 is derived.
【００２１】[0021]
【数６】 α＝（２Ｌ／ｒ・const）・（Ｖ2−const／２） 上記数式３より明かな如くＶ1及びＶ2を検出することで
磁路部材５の回転角を得ることができる。さらに、（Ｖ
1＋Ｖ2）を一定に制御できれば、磁路部材５の回転角は
上記数式６より明らか如くＶ2のみで正確に表すことが
可能となる。## EQU00006 ## .alpha. = (2L / r.const) .multidot. (V2-const / 2) The rotational angle of the magnetic path member 5 can be obtained by detecting V1 and V2, as is clear from the above mathematical expression 3. Furthermore, (V
If 1 + V2) can be controlled to be constant, the rotation angle of the magnetic path member 5 can be accurately represented only by V2, as is clear from the above equation (6).
【００２２】次に、図３に、上記図１のコイル４を励磁
してコイル２，３に生じる起電力に基づいて、磁路部材
５の位置を示す位置信号を発生する位置信号発生回路の
実施例を示す。図３の位置信号発生回路は、電圧検出回
路１１，１２、加算回路１３、制御回路１４、及び励磁
回路１５から構成されている。次に、かかる位置信号検
出回路の動作を説明する。コイル４を励磁回路１５にて
交流励磁すると、コイル２，３には起電力が生じる（図
１参照）。このコイル２，３の出力は電圧検出回路１
１，１２にそれぞれ入力し、電圧Ｖ１，Ｖ２が検出され
る。この検出電圧Ｖ１及びＶ２は加算回路１３で加算さ
れＶ３となる。この加算回路１３の出力Ｖ３は制御回路
１４の一方に入力され、他方には基準電圧Ｖrefが入力
される。この制御回路１４ではＶ３と基準電圧Ｖrefと
の差に応じた差信号Ｓ１が生成され励磁回路１５に供給
される。この差信号Ｓ１によりコイル４に印加する励磁
電圧を制御して、コイル４に流れる励磁電流を制御する
ものである。Next, FIG. 3 shows a position signal generation circuit for generating a position signal indicating the position of the magnetic path member 5 based on the electromotive force generated in the coils 2 and 3 by exciting the coil 4 of FIG. An example is shown. The position signal generating circuit shown in FIG. 3 is composed of voltage detection circuits 11 and 12, an adding circuit 13, a control circuit 14, and an exciting circuit 15. Next, the operation of the position signal detection circuit will be described. When the coil 4 is AC-excited by the excitation circuit 15, an electromotive force is generated in the coils 2 and 3 (see FIG. 1). The outputs of the coils 2 and 3 are the voltage detection circuit 1
1 and 12, respectively, and the voltages V1 and V2 are detected. The detection voltages V1 and V2 are added by the adder circuit 13 to become V3. The output V3 of the adder circuit 13 is input to one of the control circuits 14, and the reference voltage Vref is input to the other. In the control circuit 14, a difference signal S1 corresponding to the difference between V3 and the reference voltage Vref is generated and supplied to the exciting circuit 15. The difference signal S1 controls the exciting voltage applied to the coil 4 to control the exciting current flowing in the coil 4.
【００２３】この位置信号発生回路では、２つのコイル
の出力電圧の加算値Ｖ３を常に一定にすることが可能と
なる。上記数式６より磁路部材５の位置は、一方のコイ
ルの出力電圧に比例するので、Ｖ１のみを検出して磁路
部材５の位置を検出することができる。換言すれば、複
数の検出コイルのうち１つのコイルの電圧を検出して比
検出部材の位置の検出が可能となる。In this position signal generating circuit, the added value V3 of the output voltages of the two coils can be kept constant. Since the position of the magnetic path member 5 is proportional to the output voltage of one coil according to the above formula 6, the position of the magnetic path member 5 can be detected by detecting only V1. In other words, the position of the ratio detection member can be detected by detecting the voltage of one of the plurality of detection coils.
【００２４】さらに、本願発明によれば、二つのコイル
に出力電圧の加算値が一定になるようにコイル４に印加
する励磁電圧を制御しているので、経時変動等の影響を
受けることなく、常に高精度なセンサ出力が得られる。
尚、上記実施例では、Ｖ１を位置信号としたがＶ２を位
置信号としても良い。次に、図３の位置信号発生回路の
具体的電気回路例を図４に示す。Further, according to the present invention, since the excitation voltage applied to the coil 4 is controlled so that the added value of the output voltages to the two coils becomes constant, there is no influence of time-dependent changes, etc. Highly accurate sensor output is always obtained.
Although V1 is used as the position signal in the above embodiment, V2 may be used as the position signal. Next, FIG. 4 shows a specific example of an electric circuit of the position signal generating circuit of FIG.
【００２５】図４（ａ）に示す電圧検出回路はコイル２
の出力電圧を検出する電圧検出回路１１の具体例であ
る。かかる電圧検出回路は、増幅部、整流部、平滑部か
らなり、実効電圧を検出するものである。コイル２の出
力電圧は抵抗Ｒ１〜Ｒ６で決まる増幅率で増幅される。
ダイオードＤ１及びＤ２は整流作用をなし、コンデンサ
Ｃ１及びＣ２は平滑化を行う。尚、Ｒ８はオフセット調
整用である。かかる電圧検出回路の出力はＶ１となる。
コイル３の出力電圧を検出する電圧検出回路１２につい
ても同じ構成の回路を用いることが出来る。The voltage detection circuit shown in FIG.
It is a specific example of the voltage detection circuit 11 that detects the output voltage of the. The voltage detection circuit includes an amplification section, a rectification section, and a smoothing section, and detects the effective voltage. The output voltage of the coil 2 is amplified with an amplification factor determined by the resistors R1 to R6.
The diodes D1 and D2 have a rectifying function, and the capacitors C1 and C2 perform smoothing. R8 is for offset adjustment. The output of the voltage detection circuit is V1.
The voltage detection circuit 12 that detects the output voltage of the coil 3 may have the same configuration.
【００２６】図４（ｂ）に示す回路は図３の加算回路１
３及び制御回路１４に対応する。電圧検出回路１１，１
２の検出出力Ｖ１，Ｖ２が夫々入力し、合流点で加算さ
れＶ３となり、増幅器ＯＰ３の正相入力端子に入力す
る。逆相入力端子にはＧＮＤ、電源ＶＥＥ及び抵抗Ｒ１
１，１２で決まる基準電圧Ｖrefが入力し、Ｖ３とＶref
との電圧差を時間積分した差信号Ｓ１が出力される。The circuit shown in FIG. 4B is the adder circuit 1 of FIG.
3 and the control circuit 14. Voltage detection circuit 11, 1
The two detection outputs V1 and V2 are respectively input, added at the confluence point to become V3, and input to the positive phase input terminal of the amplifier OP3. GND, power supply VEE and resistor R1 are provided at the negative phase input terminal.
The reference voltage Vref determined by 1 and 12 is input, and V3 and Vref
A difference signal S1 obtained by time-integrating the voltage difference between and is output.
【００２７】図３の励磁回路１５を、図４（Ｃ）の発振
回路と図４（ｄ）のドライバー回路とによって構成す
る。図４（Ｃ）の発振回路は方形波出力Ｓ２を生成する
回路であり、コンデンサＣ４、抵抗Ｒ１６、Ｒ１７によ
って方形波出力Ｓ２の周期が決まる。図４（ｄ）のドラ
イバ回路には、図３（ｄ）の発振回路で生成された方形
波出力Ｓ２、及び制御回路１４で生成された差信号Ｓ１
が夫々入力する。方形波出力Ｓ２はトランジスタＴ１を
所定の周期でＯＮ／ＯＦＦさせ、コイル４のＡ２端子に
は方形波電圧が印加される。また、差信号Ｓ１はトラン
ジスタＴ１をＯＮ／ＯＦＦさせコイル４のＡ１端子に印
加する方形波電圧を調整して、コイル４に印加する方形
波電圧の振幅を制御する。The exciting circuit 15 shown in FIG. 3 is composed of the oscillator circuit shown in FIG. 4C and the driver circuit shown in FIG. 4D. The oscillator circuit of FIG. 4C is a circuit that generates a square wave output S2, and the cycle of the square wave output S2 is determined by the capacitor C4 and the resistors R16 and R17. The driver circuit of FIG. 4D includes a square wave output S2 generated by the oscillator circuit of FIG. 3D and a difference signal S1 generated by the control circuit 14.
Respectively input. The square wave output S2 turns on / off the transistor T1 at a predetermined cycle, and a square wave voltage is applied to the A2 terminal of the coil 4. Further, the difference signal S1 controls the amplitude of the square wave voltage applied to the coil 4 by turning on / off the transistor T1 and adjusting the square wave voltage applied to the A1 terminal of the coil 4.
【００２８】本実施例は、コイル４に印加する方形波電
圧の振幅を制御するものであるが、差信号Ｓ１によって
出力周波数が制御されるＶＣＯ出力によってコイル４を
励磁しても良い。かかる構成はコイル４に印加される方
形波電圧の周波数を制御するものである。また、ノコギ
リ波発生回路から出力されるノコギリ波と差信号Ｓ１と
をコンパレータに入力して、コンパレータから出力され
る方形波電圧にてコイル４を励磁しても良い。かかる構
成はコイル４に印加される方形波電圧のデューティ比を
制御するものである。Although the present embodiment controls the amplitude of the square wave voltage applied to the coil 4, the coil 4 may be excited by the VCO output whose output frequency is controlled by the difference signal S1. Such a configuration controls the frequency of the square wave voltage applied to the coil 4. Alternatively, the sawtooth wave output from the sawtooth wave generation circuit and the difference signal S1 may be input to the comparator to excite the coil 4 with the square wave voltage output from the comparator. Such a configuration controls the duty ratio of the square wave voltage applied to the coil 4.
【００２９】[0029]
【発明の効果】以上述べたように、本発明の磁気式位置
センサは、非接触型であるので耐久性があり、かつ構造
が簡単である。また、可動の磁性部材と固定の磁性部材
とのギャップは高精度である必要がないので加工が容易
である。更に、ホール素子等のかわりにコイルを用いて
いるため温度特性に大きく影響されることなく被検知対
象に連動する可動部材の位置を高精度に検出することが
可能である。更に、複数のコイルの出力電圧の加算値が
一定になるように制御し、かつ、１つのコイルの出力電
圧を検出して前記可動部材の位置を検出できるように回
路構成されているため、経時変動等の影響を受けること
なく簡単な回路構成で高精度な磁気式位置センサの出力
を得ることができる。As described above, the magnetic position sensor of the present invention is a non-contact type, so it is durable and has a simple structure. In addition, the gap between the movable magnetic member and the fixed magnetic member does not need to be highly accurate, so that processing is easy. Furthermore, since the coil is used instead of the Hall element or the like, it is possible to detect the position of the movable member that interlocks with the detection target with high accuracy without being greatly affected by the temperature characteristics. Furthermore, the circuit is configured so that the added value of the output voltages of the plurality of coils is controlled to be constant, and the output voltage of one coil can be detected to detect the position of the movable member. It is possible to obtain a highly accurate output of the magnetic position sensor with a simple circuit configuration without being affected by fluctuations and the like.
【図１】 本発明に係る磁気式位置センサの実施例を示
す図であり図４（ａ）はセンサの正面図、図４（ｂ）は
図４（ａ）のＢ−Ｂ線からみた断面図を夫々示す。FIG. 1 is a diagram showing an embodiment of a magnetic position sensor according to the present invention, FIG. 4 (a) is a front view of the sensor, and FIG. 4 (b) is a cross section taken along line BB of FIG. 4 (a). The figures are shown respectively.
【図２】 本発明に係る磁気式位置センサの原理を示す
概念図である。FIG. 2 is a conceptual diagram showing the principle of a magnetic position sensor according to the present invention.
【図３】 本発明に係る磁気式位置センサの位置信号発
生回路の構成を示すブロック図である。FIG. 3 is a block diagram showing a configuration of a position signal generating circuit of a magnetic position sensor according to the present invention.
【図４】 本発明に係る磁気式位置センサの位置信号発
生回路の具体例を示す電気回路図である。FIG. 4 is an electric circuit diagram showing a specific example of a position signal generating circuit of a magnetic position sensor according to the present invention.
１、７ 磁性部材 ２、３、４ コイル ９、１０ ギャップ ５ 磁路部材 ６ 回動シャフト Ｒ 電気抵抗 Ｃ コンデンサ ＯＰ オペアンプ Ｄ ダイオード ＶＣＣ、ＶＥＥ、ＶＤＤ 直流電源 1, 7 Magnetic member 2, 3, 4 Coil 9, 10 Gap 5 Magnetic path member 6 Rotating shaft R Electric resistance C Capacitor OP Operational amplifier D Diode VCC, VEE, VDD DC power supply
Claims (3)
第１の磁路形成手段と、前記第１の磁路形成手段に対し
て非接触で所定範囲に亘って相対的に移動可能であって
前記第１閉磁路を２つの閉磁路に分岐する分岐磁路を形
成する第２の磁路形成手段と、前記所定範囲を挟む位置
にて前記第１閉磁路に鎖交する２つの第１及び第２コイ
ルと、前記分岐磁路に鎖交する１つの第３コイルと、前
記３つのうち１つのコイルを交流励磁し、他の２つのコ
イルに発生する起電力を検出して前記第２の磁路形成手
段の位置信号を発生する位置信号発生手段と、を有する
磁気式位置センサであって、前記位置信号発生手段は、
前記他の２つのコイルの検出起電力の加算値に応じて、
前記１つのコイルに流れる励磁電流を制御することを特
徴とする磁気式位置センサ。1. A first magnetic path forming means that forms at least one first closed magnetic path, and is relatively movable over a predetermined range in a non-contact manner with respect to the first magnetic path forming means. Second magnetic path forming means for forming a branch magnetic path for branching the first closed magnetic path into two closed magnetic paths, and two first magnetic paths interlinking with the first closed magnetic path at positions sandwiching the predetermined range. And a second coil, one third coil interlinking with the branch magnetic path, and one of the three coils is AC-excited, and electromotive force generated in the other two coils is detected to detect the second coil. A position signal generating means for generating a position signal of the magnetic path forming means, and the position signal generating means,
According to the added value of the detected electromotive force of the other two coils,
A magnetic type position sensor characterized by controlling an exciting current flowing through the one coil.
イルを交流励磁する励磁手段と、前記他の２つのコイル
に生じる起電力を検出する検出手段と、前記検出手段の
検出起電力を加算する加算手段と、前記加算手段の加算
値と基準値とを比較して差信号を生成し、前記差信号に
応じて前記励磁手段の励磁電流を制御する制御手段と、
からなり、前記検出手段の前記他の２つのコイルの少な
くとも一方を前記第２の磁路形成手段の位置を表す検出
出力とする出力手段と、からなることを特徴とする磁気
式位置センサ。2. The position signal generating means adds an exciting means for exciting the one coil with an alternating current, a detecting means for detecting an electromotive force generated in the other two coils, and an electromotive force detected by the detecting means. And a control means for comparing the added value of the adding means with a reference value to generate a difference signal and controlling the exciting current of the exciting means according to the difference signal.
And a means for outputting at least one of the other two coils of the detecting means as a detection output indicating the position of the second magnetic path forming means.
一方に一端が固設した固定分岐磁性部材を更に含み、前
記可動分岐磁性部材は前記固定分岐磁性部材の他端の近
傍の回転中心軸の回りに回動自在であり、かつ前記対向
部の他方が前記可動分岐磁性部材の先端の可動軌跡に沿
って延在していることを特徴とする請求項１及び２のい
ずれか１記載の磁気式位置センサ。3. The second magnetic path forming means further includes a fixed branch magnetic member having one end fixed to one of the facing portions, and the movable branch magnetic member is near the other end of the fixed branch magnetic member. 3. The rotary unit according to claim 1, wherein the movable branch magnetic member is rotatable about a central axis of rotation and the other of the facing portions extends along a movable locus of a tip of the movable branch magnetic member. 1. The magnetic position sensor according to 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13211894A JPH07332913A (en) | 1994-06-14 | 1994-06-14 | Magnetic positional sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13211894A JPH07332913A (en) | 1994-06-14 | 1994-06-14 | Magnetic positional sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07332913A true JPH07332913A (en) | 1995-12-22 |
Family
ID=15073841
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13211894A Pending JPH07332913A (en) | 1994-06-14 | 1994-06-14 | Magnetic positional sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07332913A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08297007A (en) * | 1995-04-27 | 1996-11-12 | Mikuni Corp | Magnetic position sensor |
| JP2010164594A (en) * | 2003-02-21 | 2010-07-29 | Fisher Controls Internatl Llc | Magnetic position sensor including integrated hall effect switch |
-
1994
- 1994-06-14 JP JP13211894A patent/JPH07332913A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08297007A (en) * | 1995-04-27 | 1996-11-12 | Mikuni Corp | Magnetic position sensor |
| JP2010164594A (en) * | 2003-02-21 | 2010-07-29 | Fisher Controls Internatl Llc | Magnetic position sensor including integrated hall effect switch |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6291989B1 (en) | Differential magnetic position sensor with adaptive matching for detecting angular position of a toothed target wheel | |
| US8063628B2 (en) | Sensor device for an electric machine | |
| US5982171A (en) | Sensing device for detecting the angular displacement and relative position of a member of magnetic material | |
| US6674280B1 (en) | Position detection apparatus with distributed bridge sensor | |
| US20030102862A1 (en) | Self-induction-type position detector device for detecting object position | |
| JP2004028809A (en) | Actuator | |
| JP2001235307A (en) | Rotary type position detecting apparatus | |
| US6211588B1 (en) | Electromoter having a position sensor with a plurality of field sensitive elements on a semiconductor chip | |
| JP3605968B2 (en) | Rotation angle sensor | |
| US6874750B2 (en) | Electromagnetic actuator and valve driver and position or speed sensor comprising it | |
| JPH10332722A (en) | Rotational speed detector | |
| US6229231B1 (en) | Reciprocating motor having controllable rotor position | |
| WO2005040730A1 (en) | Rotation angle detection device | |
| JPH03233317A (en) | Rotation angle sensor | |
| JPH075189A (en) | Inductive sensor | |
| JPH07332913A (en) | Magnetic positional sensor | |
| US7323864B2 (en) | Absolute angular position sensor on 360 of a rotating element | |
| JP3183620B2 (en) | Rotation angle detector | |
| US5394042A (en) | Angular position homopolar reluctance sensor | |
| JP3161962B2 (en) | Rotation angle detector | |
| JPH07251305A (en) | Power tool with chuck device | |
| JP4336070B2 (en) | Rotary position detector | |
| JPH06221865A (en) | Measuring device for detecting rotating angle | |
| JPH08304011A (en) | Magnetic angle sensor | |
| GB2053487A (en) | Inductive differential position sensor |