JPH01235811A - Potentiometer - Google Patents
PotentiometerInfo
- Publication number
- JPH01235811A JPH01235811A JP6146888A JP6146888A JPH01235811A JP H01235811 A JPH01235811 A JP H01235811A JP 6146888 A JP6146888 A JP 6146888A JP 6146888 A JP6146888 A JP 6146888A JP H01235811 A JPH01235811 A JP H01235811A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- members
- potentiometer
- molding method
- powder
- 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 claims abstract description 120
- 239000000843 powder Substances 0.000 claims abstract description 19
- 238000000465 moulding Methods 0.000 claims abstract description 16
- 239000011230 binding agent Substances 0.000 claims abstract description 9
- 230000005294 ferromagnetic effect Effects 0.000 claims description 10
- 230000004907 flux Effects 0.000 claims description 4
- 238000000034 method Methods 0.000 abstract description 16
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 10
- 230000035699 permeability Effects 0.000 abstract description 9
- 239000000463 material Substances 0.000 abstract description 6
- 238000000748 compression moulding Methods 0.000 abstract description 5
- 239000003302 ferromagnetic material Substances 0.000 abstract description 5
- 229910052742 iron Inorganic materials 0.000 abstract description 5
- 238000001125 extrusion Methods 0.000 abstract description 2
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 239000006247 magnetic powder Substances 0.000 abstract 1
- 230000005389 magnetism Effects 0.000 abstract 1
- 230000001590 oxidative effect Effects 0.000 abstract 1
- 238000005096 rolling process Methods 0.000 description 11
- BGPVFRJUHWVFKM-UHFFFAOYSA-N N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] Chemical compound N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] BGPVFRJUHWVFKM-UHFFFAOYSA-N 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 238000010273 cold forging Methods 0.000 description 1
- 239000010960 cold rolled steel Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
Landscapes
- Transmission And Conversion Of Sensor Element Output (AREA)
Abstract
Description
【発明の詳細な説明】
〔概要〕
磁石によって発生した磁界が磁性部材から漏洩する漏洩
磁界を磁気センサにて検出し、該磁性部材または該磁気
センサの少なくとも一方が該磁性部材の長さ方向に移動
することにより、アナログ出力で絶対位置を測定可能な
漏洩磁界型ポテンショメータに関し、
製品間における出力特性のばらつきを減少せしめ、位置
検出の精度および信頼性の改善を目的とし、
該磁性部材が、加圧成形法により強磁性体粉末をバイン
ダで機械的および磁気的に結合してなることを特徴とし
構成する。[Detailed Description of the Invention] [Summary] A magnetic sensor detects a leakage magnetic field generated by a magnet leaking from a magnetic member, and at least one of the magnetic member or the magnetic sensor extends in the length direction of the magnetic member. With respect to leakage magnetic field type potentiometers that can measure absolute position with analog output by moving, the magnetic member is It is characterized in that it is made by mechanically and magnetically bonding ferromagnetic powder with a binder using a compression molding method.
本発明はアナログ出力で絶対位置を測定可能なポテンシ
ョメータ、特に磁石と磁性部材を用いて構成した閉磁路
構造体における磁性部材の改良に関する。The present invention relates to a potentiometer capable of measuring absolute position with an analog output, and particularly to improvements in a magnetic member in a closed magnetic circuit structure constructed using a magnet and a magnetic member.
本出瀬人は、漏洩磁界を発生する閉磁路構造体と該漏洩
磁界を検出する磁気センサとを具え、直線上における絶
対位置を非接触に測定できるポテンショメータ（特願昭
６０−２０２８３２）および、回転角度を非接触に測定
できる回転ポジショナ（特願昭６１−２９２５８７）を
提案した。Seito Hondade has disclosed a potentiometer that is equipped with a closed magnetic circuit structure that generates a leakage magnetic field and a magnetic sensor that detects the leakage magnetic field, and is capable of non-contact measurement of an absolute position on a straight line (Japanese Patent Application No. 202832/1983); We proposed a rotary positioner (Japanese Patent Application No. 61-292587) that can measure the rotation angle without contact.
第１図は特願昭６０−２０２８３２のポテンショメータ
の構成例の平面図、第２図は特願昭６１−２９２５８７
の回転ポジショナの構成例の平面図である。Figure 1 is a plan view of an example of the configuration of a potentiometer in Japanese Patent Application No. 60-202832, and Figure 2 is in Japanese Patent Application No. 61-292587.
FIG. 2 is a plan view of a configuration example of a rotational positioner.
第１図において、ポテンショメータｌは互いに平行な２
枚の磁性部材２，３の両端間に磁石４．５を配設してな
り、一対の磁性部材２．３と極性が逆向きである一対の
磁石４，５とは、閉磁路構造体６を構成している。In FIG. 1, two potentiometers l are parallel to each other.
A pair of magnets 4.5 are arranged between both ends of the magnetic members 2, 3, and the pair of magnets 4, 5 whose polarity is opposite to that of the pair of magnetic members 2.3 is the closed magnetic circuit structure 6. It consists of
このようなポテンショメータ１は、磁石４．５から発生
する磁束が主に磁性部材２，３を通り、磁性部材２，３
から図中に矢印で示すような漏洩磁界Ｍが発生する。漏
洩磁界Ｍは磁石４または５に近づくに従って強く、かつ
、磁石４，５の極性によって右半分と左半分とで向きが
逆方向になり、中央位置で最小となる。In such a potentiometer 1, the magnetic flux generated from the magnet 4.5 mainly passes through the magnetic members 2 and 3.
A leakage magnetic field M is generated as shown by the arrow in the figure. The leakage magnetic field M becomes stronger as it approaches the magnet 4 or 5, and is opposite in direction between the right half and the left half depending on the polarity of the magnets 4 and 5, and becomes minimum at the center position.
そこで、閉磁路構造体６の内側に配設した磁気センサ７
を磁性部材２，３の長さ方向に可動式にすれば、該長さ
方向に磁気センサ７の位置をアナログ式、かつ、非接触
に検出することができる。Therefore, the magnetic sensor 7 disposed inside the closed magnetic path structure 6
If it is movable in the length direction of the magnetic members 2 and 3, the position of the magnetic sensor 7 can be detected in the length direction in an analog and non-contact manner.
第２図において、回転ポジショナ（回転型ポテンショメ
ータ）１１は、円環形状の磁性部材１２の一部に磁石１
３を設けた閉磁路構造体１４と、閉磁路構造体１４から
の漏洩磁界を検知する磁気センサ１５と、閉磁路構造体
１４に対しその内側に対向する円環形状の磁性部材１６
を配設し、閉磁路構造体１４および磁性体１６の中心軸
Ｃと同軸に支持された回転軸１７に一端を固着したアー
ム１８の他端に、磁気センサ１５を固着してなる。In FIG. 2, a rotary positioner (rotary potentiometer) 11 has a magnet 1 attached to a part of an annular magnetic member 12.
3, a magnetic sensor 15 for detecting a leakage magnetic field from the closed magnetic path structure 14, and an annular magnetic member 16 facing inside the closed magnetic path structure 14.
A magnetic sensor 15 is fixed to the other end of an arm 18 which has one end fixed to a rotating shaft 17 coaxially supported with the central axis C of the closed magnetic path structure 14 and the magnetic body 16.
このような回転ポジショナ１１は、磁石１３から発生す
る磁束は主に磁性部材１２を通り、磁性部材１２から図
中に矢印で示すような漏洩磁界Ｍが発生する。漏洩磁界
Ｍは磁石１３に近づ（に従って強く、磁石１３から最も
離れた位置で最小となる。In such a rotary positioner 11, the magnetic flux generated from the magnet 13 mainly passes through the magnetic member 12, and a leakage magnetic field M is generated from the magnetic member 12 as shown by the arrow in the figure. The leakage magnetic field M becomes stronger as it approaches the magnet 13, and becomes minimum at a position farthest from the magnet 13.
そこで、閉磁路構造体１４と磁性部材１６とを固定し回
転軸１７を回転させたとき、回転軸１７の回転角度は、
磁性部材１２の長さ方向に移動する磁気センサ１５の出
力によってアナログ式、かつ、非接触に検出することが
できる。Therefore, when the closed magnetic circuit structure 14 and the magnetic member 16 are fixed and the rotating shaft 17 is rotated, the rotation angle of the rotating shaft 17 is
The output of the magnetic sensor 15 that moves in the length direction of the magnetic member 12 allows for analog and non-contact detection.
従来のポテンショメータにおいて、漏洩磁界を発生させ
る磁性部材には、５Ｏ３−４３０等の磁性ステンレス板
または５ＰＣＣ−１５等の冷間圧延鋼板を用いていた。In conventional potentiometers, a magnetic stainless steel plate such as 5O3-430 or a cold rolled steel plate such as 5PCC-15 has been used as a magnetic member that generates a leakage magnetic field.
透磁率μが比較的低い１００〜２００程度であるこれら
の磁路材板は、何れも圧延により製造されたものであり
、その透磁率μは圧延条件によってばらつきが生じると
共に、圧延方向によっても異なるため、かかる磁路材板
から切り出した磁性部材に透磁率μのばらつきが避は難
いという問題点があった。These magnetic path material plates, which have a relatively low magnetic permeability μ of about 100 to 200, are all manufactured by rolling, and the magnetic permeability μ varies depending on the rolling conditions and also varies depending on the rolling direction. Therefore, there is a problem in that it is difficult to avoid variations in magnetic permeability μ in magnetic members cut out from such magnetic path material plates.
第３図は圧延により製造された強磁性板から切り出した
磁性部材を組み込んだ従来の回転型ポテンショメータの
漏洩磁界と磁気センサの回転角度との関係を示す図であ
る。ただし、漏洩磁界は磁気センサの出力より算出した
値である。FIG. 3 is a diagram showing the relationship between the leakage magnetic field of a conventional rotary potentiometer incorporating a magnetic member cut out from a ferromagnetic plate manufactured by rolling and the rotation angle of a magnetic sensor. However, the leakage magnetic field is a value calculated from the output of the magnetic sensor.
第３図において、閉磁路構造体１４の中心と磁石１３の
中心とを結ぶ方向を磁性部材１２の形状方向Ａとしたと
き、図中の実線は強磁性板の圧延方向Ｂと磁性部材の形
状方向Ａとが一致する閉磁路構造体１４の漏洩磁界の測
定値をプロットし繋いだもの、図中の破線は強磁性板の
圧延方向Ｂと磁性部材の形状方向Ａとが９０度である閉
磁路構造体１４の漏洩磁界の測定値をプロットし繋いだ
ものである。In FIG. 3, when the direction connecting the center of the closed magnetic circuit structure 14 and the center of the magnet 13 is defined as the shape direction A of the magnetic member 12, the solid line in the figure indicates the rolling direction B of the ferromagnetic plate and the shape of the magnetic member. The measured values of the leakage magnetic field of the closed magnetic circuit structure 14 whose direction A coincides with the direction A are plotted and connected, and the broken line in the figure shows the closed magnetic field where the rolling direction B of the ferromagnetic plate and the shape direction A of the magnetic member are 90 degrees. The measured values of the leakage magnetic field of the path structure 14 are plotted and connected.
第３図から明らかなように、実線で示す漏洩磁界特性と
破線で示す漏洩磁界特性とは、圧延方向Ｂ方向によって
透磁率μが一致せず、最大で１０％程度の差が生じる。As is clear from FIG. 3, the leakage magnetic field characteristics shown by the solid line and the leakage magnetic field characteristics shown by the broken line do not match in magnetic permeability μ depending on the rolling direction B, and there is a difference of about 10% at maximum.
また、圧延加工された強磁性板はその圧延方向によって
透磁率μが異なると共に、圧延温度等の制御し難い圧延
条件によっても差が生じる。Further, the magnetic permeability μ of a rolled ferromagnetic plate differs depending on the rolling direction, and also varies depending on rolling conditions such as rolling temperature, which are difficult to control.
本発明は、ポテンショメータに使用する漏洩磁界発生用
磁性部材の透磁率μを一定化せしめ、磁気センサからの
出力特性を安定にすることを目的とする。An object of the present invention is to make constant the magnetic permeability μ of a magnetic member for generating a leakage magnetic field used in a potentiometer, and to stabilize output characteristics from a magnetic sensor.
上記目的は本発明によれば、磁石によって発生した磁束
が磁性部材から漏洩する漏洩磁界を磁気センサにて検出
し、該磁性部材または該磁気センサの少なくとも一方が
該磁性部材の長さ方向に移、動するポテンショメータに
おいて、
該磁性部材が、加圧成形法により強磁性体粉末をバイン
ダで機械低および磁気的に結合してなることを特徴とす
る構成とし、達成される。According to the present invention, the above object is to detect a leakage magnetic field in which magnetic flux generated by a magnet leaks from a magnetic member using a magnetic sensor, and at least one of the magnetic member or the magnetic sensor moves in the length direction of the magnetic member. In the moving potentiometer, the magnetic member is formed by mechanically and magnetically bonding ferromagnetic powder with a binder using a pressure molding method.
圧延加工より加工条件の管理が容易であり、透磁率μに
方向性がない加圧成形法を利用して構成した上記手段、
即ち、加圧成形法により強磁性体粉末をバインダで結合
した磁性部材を使用して閉磁路構造体を構成したことに
より、磁気センサで検出される該閉磁路構造体の漏洩磁
界は、製品間のばらつきが減少するため、ポテンショメ
ータの性能が向上される。The above-mentioned means is configured using a pressure forming method in which the processing conditions are easier to control than in rolling processing, and the magnetic permeability μ has no directionality;
In other words, by constructing a closed magnetic circuit structure using a magnetic member in which ferromagnetic powder is bonded with a binder using a pressure molding method, the leakage magnetic field of the closed magnetic circuit structure detected by a magnetic sensor is reduced between the products. The performance of the potentiometer is improved because the variation in is reduced.
以下に、前出の第１図と第２図を用いて本発明の実施例
によるポテンショメータの構成を説明する。The configuration of a potentiometer according to an embodiment of the present invention will be explained below using FIGS. 1 and 2 mentioned above.
本発明のポテンショメータは、第１図および第２図に示
す磁性部材２，３．１２．１６が、加圧成形法によって
強磁性体粉末を、バインダで機械的および磁気的に結合
させたものであり、強磁性体材料である純鉄等の磁性体
の微粉末の表面を酸化させ一部分（中心部）のみに磁性
を具えた鉄シンター材粉末の加圧成形または、純鉄等の
磁性体の微粉末の表面に非磁性であるアルミニウム等を
被着させた粉末の加圧成形あるいは、純鉄等の磁性体の
微粉末とアルミニウムや合成樹脂等の非磁性の微粉末と
を混合しそれを加圧成形したものである。In the potentiometer of the present invention, the magnetic members 2, 3, 12, and 16 shown in FIGS. 1 and 2 are made by mechanically and magnetically bonding ferromagnetic powder with a binder using a pressure molding method. The surface of fine powder of magnetic material such as pure iron, which is a ferromagnetic material, is oxidized to make only a part (center) magnetic. Pressure molding of iron sinter material powder, or Pressure molding of powder with non-magnetic aluminum, etc. coated on the surface of fine powder, or mixing fine powder of magnetic material such as pure iron with non-magnetic fine powder such as aluminum or synthetic resin. It is pressure molded.
なお、前記粉体材料を所望の磁性部材２．３，１２゜１
６にする加圧成形には、例えばＨＩＣ法（ｈｏｔｉｓｏ
ｓｔａｔｉｃ ｐｒｅｓｓｉｎｇＨ高温等方圧縮成形高
温等方圧縮注形法ｏｌｄ １ｓｏｓｔａｔｉｃ ｐｒｅ
ｓｓｉｎｇ；冷間等方圧縮成形法）、押出しプレス成形
法、熱間鍛造法、冷間鍛造法が利用される。Note that the powder material is used as a desired magnetic member 2.3, 12°1
For example, the HIC method (hotiso
static pressing H high temperature isostatic compression molding high temperature isostatic compression molding method old 1sostatic pre
ssing (cold isostatic compression molding method), extrusion press molding method, hot forging method, and cold forging method.
このようにして形成された磁性部材２．３．１２．１６
を組み込んだポテンショメータは、従来のポテンショメ
ータと同じく磁気センサの直線上における絶対位置く直
線的移動距離）および、回転円上における絶対位置く回
転角度）が検出されることになり、磁性部材２．３．１
２からの漏洩磁界は、磁性部材２，３．１２．１６の透
磁率μが強磁性粉末とバインダおよび成形条件を同一に
したとき一定化されることになり、その製品間のばらつ
きは２％以下にできる。Magnetic member 2.3.12.16 thus formed
Like conventional potentiometers, a potentiometer incorporating a magnetic sensor detects the absolute position (linear movement distance) on a straight line and the absolute position (rotation angle) on a rotating circle, and the magnetic member 2.3 .1
The leakage magnetic field from 2 becomes constant when the magnetic permeability μ of magnetic member 2, 3, 12, 16 is made the same as the ferromagnetic powder, binder, and molding conditions, and the variation between products is 2%. You can do the following.
前述の本発明によるポテンショメータにおいて、磁性部
材２，３．１２の漏洩磁界は、使用した粉体材料とその
成形方法および成形条件を同一にしたとき同一特性とな
り、製品間における漏洩磁界のばらつきは、従来の１０
％から２％以下に減少する。その結果、ポテンショメー
タの性能と信幀性を向上し、磁気センサの出力特性を位
置情頼に較正することが容易となった効果を有する。In the aforementioned potentiometer according to the present invention, the leakage magnetic fields of the magnetic members 2, 3, 12 have the same characteristics when the powder materials used, the molding method, and the molding conditions are the same, and the variations in the leakage magnetic fields between products are as follows: Conventional 10
% to less than 2%. As a result, the performance and reliability of the potentiometer are improved, and the output characteristics of the magnetic sensor can be easily calibrated based on position information.
第１図はリニアポテンショメータの構成例を示す平面図
、
第２図は回転型ポテンショメータの構成例を示す平面図
、
第３図は従来の回転型ポテンショメータの漏洩磁界の特
性図、
である。
図中において、
１．１１はポテンショメータ、
２．３．１２は磁性部材、
５．１３は磁石、
７．１５は磁気センサ、
Ｍは漏洩磁界、
を示す。
ワ０ア圧ぐテン゛ンヨメータのオ糞戚イタ”ｊ乏ホ了手
ｌｒ］第 １ 図
口転型ポテンツヨメータめ万愚へ４ダ′」と示Ｊ平面図
第 ２ Ｄ口FIG. 1 is a plan view showing an example of the configuration of a linear potentiometer, FIG. 2 is a plan view showing an example of the configuration of a rotary potentiometer, and FIG. 3 is a characteristic diagram of leakage magnetic field of a conventional rotary potentiometer. In the figure, 1.11 is a potentiometer, 2.3.12 is a magnetic member, 5.13 is a magnet, 7.15 is a magnetic sensor, and M is a leakage magnetic field.゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛゛〕〔〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕〕
Claims (1)
（２、３、１２）から漏洩する漏洩磁界（Ｍ）を磁気セ
ンサ（７、１５）にて検出し、該磁性部材（２、３、１
２）または該磁気センサ（７、１５）の少なくとも一方
が該磁性部材（２、３、１２）の長さ方向に移動するポ
テンショメータにおいて、 該磁性部材（２、３、１２）が、加圧成形法により強磁
性体粉末をバインダで機械的および磁気的に結合してな
ることを特徴とするポテンショメータ。[Claims] The leakage magnetic field (M) in which the magnetic flux generated by the magnets (4, 5, 13) leaks from the magnetic members (2, 3, 12) is detected by the magnetic sensor (7, 15). Magnetic member (2, 3, 1
2) or a potentiometer in which at least one of the magnetic sensors (7, 15) moves in the length direction of the magnetic member (2, 3, 12), wherein the magnetic member (2, 3, 12) is formed by pressure molding. A potentiometer characterized in that it is made by mechanically and magnetically bonding ferromagnetic powder with a binder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6146888A JPH01235811A (en) | 1988-03-15 | 1988-03-15 | Potentiometer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6146888A JPH01235811A (en) | 1988-03-15 | 1988-03-15 | Potentiometer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01235811A true JPH01235811A (en) | 1989-09-20 |
Family
ID=13171910
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6146888A Pending JPH01235811A (en) | 1988-03-15 | 1988-03-15 | Potentiometer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01235811A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2022502996A (en) * | 2018-10-04 | 2022-01-11 | カッツフォース インコーポレイテッドCutsforth, Inc. | Systems and methods for monitoring the condition of one or more components of an electrical machine |
-
1988
- 1988-03-15 JP JP6146888A patent/JPH01235811A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2022502996A (en) * | 2018-10-04 | 2022-01-11 | カッツフォース インコーポレイテッドCutsforth, Inc. | Systems and methods for monitoring the condition of one or more components of an electrical machine |
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