JPH0739923B2 - Magnetic detector - Google Patents
Magnetic detectorInfo
- Publication number
- JPH0739923B2 JPH0739923B2 JP28351486A JP28351486A JPH0739923B2 JP H0739923 B2 JPH0739923 B2 JP H0739923B2 JP 28351486 A JP28351486 A JP 28351486A JP 28351486 A JP28351486 A JP 28351486A JP H0739923 B2 JPH0739923 B2 JP H0739923B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- saturable
- magnetic detector
- output voltage
- detector
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000006073 displacement reaction Methods 0.000 claims description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 14
- 238000010586 diagram Methods 0.000 description 14
- 229910052742 iron Inorganic materials 0.000 description 7
- 230000004907 flux Effects 0.000 description 6
- 230000005389 magnetism Effects 0.000 description 5
- 230000005284 excitation Effects 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 238000001514 detection method Methods 0.000 description 3
- 229910000889 permalloy Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、エレベータなど各種の搬送車を所定の位置に
高精度で且つ滑らかに停止させるのに必要な位置検出な
どに用いる磁気検出器に関するものである。Description: TECHNICAL FIELD The present invention relates to a magnetic detector used for position detection and the like required to stop various transport vehicles such as an elevator at a predetermined position with high accuracy and smoothly. It is a thing.
本発明は、発磁体と可飽和コイルを有する磁気検出器に
おいて、発磁体として１対の磁石片を対向させた構造の
ものを使用することにより、磁気検出器の発磁体に対す
る相対的変位方向と直角な方向の位置ずれが検出器の性
能に影響しないようにしたものである。According to the present invention, in a magnetic detector having a magnetizer and a saturable coil, by using a magnetizer having a structure in which a pair of magnet pieces are opposed to each other, the relative displacement direction of the magnetometer with respect to the magnetizer is determined. This is to prevent misalignment in the perpendicular direction from affecting the performance of the detector.
磁気検出器に用いる可飽和コイルは、パーマロイの如き
可飽和コアに巻線を施したもので既に公知である。可飽
和コイルは、そのＢ−Ｈ特性が未飽和領域で直線性が良
く、飽和領域で平坦であり、且つヒステリシスが小さ
く、温度特性が大変良いという特徴をもっている。この
パーマロイのコアを高周波励磁により常に飽和させてお
くと、外部磁界が加わったとき、コア内部の磁束密度の
変化量が外部磁界に直線的に比例して変化する。第12図
は、外部磁界がないときのコイルの磁界の向き及びその
大きさ並びにそのときのコアの磁束密度の変化量を示
す。即ち、コアの磁束密度は、励磁により０からBs（飽
和磁束密度）まで変化している。第13図は、外部磁界が
加わったときの様子を示すもので、コアの磁束密度はBe
xからBsまで変化する。コアに巻線されたコイルは、励
磁に用いられると同時にそのインダクタンスの変化を取
出すのに用いられる。コイルのインダクタンスは、単位
時間当たりの磁束の変化に比例するから、この場合、コ
イルのインダクタンスが外部磁界に比例して変化するこ
とになる。コアの励磁方向と外部磁界の方向が同じであ
れば、インダクタンスは増大し、逆であれば減少する。
このような原理に基いて磁気を検出するために、パーマ
ロイ・コアに巻線を施した可飽和コイル、コアを励磁す
るための発振回路、直流電圧を取出すための検波整流回
路より構成したものが磁気検出器である。The saturable coil used in the magnetic detector is a well-known saturable core such as permalloy having a winding. The saturable coil is characterized in that its BH characteristic has good linearity in the unsaturated region, is flat in the saturated region, has a small hysteresis, and has very good temperature characteristic. When the core of this permalloy is always saturated by high-frequency excitation, when an external magnetic field is applied, the amount of change in the magnetic flux density inside the core changes linearly in proportion to the external magnetic field. FIG. 12 shows the direction and magnitude of the magnetic field of the coil when there is no external magnetic field, and the amount of change in the magnetic flux density of the core at that time. That is, the magnetic flux density of the core changes from 0 to Bs (saturation magnetic flux density) due to excitation. Fig. 13 shows the situation when an external magnetic field is applied. The magnetic flux density of the core is Be
It varies from x to Bs. The coil wound around the core is used not only for excitation but also for extracting the change in its inductance. Since the inductance of the coil is proportional to the change of the magnetic flux per unit time, in this case, the inductance of the coil changes in proportion to the external magnetic field. If the excitation direction of the core and the direction of the external magnetic field are the same, the inductance increases, and if they are opposite, the inductance decreases.
In order to detect magnetism based on such a principle, a saturable coil wound around a permalloy core, an oscillator circuit for exciting the core, and a detection rectifier circuit for extracting a DC voltage are used. It is a magnetic detector.
本発明者は、さきに、発磁体と可飽和コイルを有し各種
の搬送車の位置検出や無人搬送車の誘導などに用いうる
磁気検出器を発明し、特願昭61−16340号（特公平６−2
5641号）として出願した。第９図はその基本的構成を示
す図、第10図はその動作を示す出力電圧曲線図である。
第９図において、L1,L2,L3,L4は磁気センサを構成する
可飽和コイル、Ｍは発磁体、Ｗは発磁体の移動方向の
幅、OSCは高周波（例えば50kHz）パルス発振器、Ｒｓは
直列抵抗、D1及びD2はダイオード、R1及びR2は出力抵
抗、C1,C2及びC3は平滑容量を示す。第10図は、発磁体
Ｍと磁気検出器の磁気センサとの間隔ｄを可変として発
磁体Ｍを幅Ｗの方向（Ｘ方向）に移動させたときの出力
電圧を示し、間隔ｄが増加すると、出力電圧は減少して
いる。The present inventor has previously invented a magnetic detector having a magnetizing body and a saturable coil, which can be used for position detection of various transport vehicles and guidance of unmanned transport vehicles. Fair 6-2
No. 5641) was filed. FIG. 9 is a diagram showing its basic configuration, and FIG. 10 is an output voltage curve diagram showing its operation.
In FIG. 9, L 1 , L 2 , L 3 , and L 4 are saturable coils forming a magnetic sensor, M is a magnet, W is the width of the magnet in the moving direction, and OSC is a high-frequency (eg, 50 kHz) pulse oscillator. , R s is a series resistance, D 1 and D 2 are diodes, R 1 and R 2 are output resistances, and C 1 , C 2 and C 3 are smoothing capacitors. FIG. 10 shows the output voltage when the distance d between the magnetic body M and the magnetic sensor of the magnetic detector is variable and the magnetic body M is moved in the width W direction (X direction). , The output voltage is decreasing.
上記の磁気検出器では発磁体Ｍとして矩形状の一様な厚
さの磁石板を鉄板に貼り付けたものを使用している。磁
石板のＸ方向の長さＷは、磁気センサと関連して適当に
定める。第11図は発磁体Ｍと磁気検出器との相対的位置
関係を示すもので、同図Ａは平面図、同図Ｂは側面図で
ある。磁気検出器が上記のような発磁体に対向してＸ方
向に移動するとき、磁気検出器の位置がＹ又はＺ方向に
変動すると、磁気検出器の出力に影響する。発磁体の方
が移動しても、同様である。第11図の場合、発磁体Ｍの
Ｙ方向の長さＬを充分大きく取れば、中心から±L/4の
範囲ではＹ方向のずれに関係なく一定の出力を生ずる
が、Ｚ方向の取付間隔ｄが変化すると、第10図に示すよ
うに出力電圧が大きく変化して好ましくない。In the above-mentioned magnetic detector, as the magnetizer M, a rectangular magnet plate having a uniform thickness is attached to an iron plate. The length W of the magnet plate in the X direction is appropriately determined in relation to the magnetic sensor. FIG. 11 shows the relative positional relationship between the magnetic generator M and the magnetic detector. FIG. 11A is a plan view and FIG. 11B is a side view. When the position of the magnetic detector moves in the Y or Z direction when the magnetic detector moves in the X direction facing the above-mentioned magnetism generating body, the output of the magnetic detector is affected. The same is true even if the magnetized body moves. In the case of FIG. 11, if the length L of the magnet M in the Y direction is made sufficiently large, a constant output is produced in the range of ± L / 4 from the center regardless of the deviation in the Y direction. If d changes, the output voltage changes greatly as shown in FIG. 10, which is not preferable.
したがつて、本発明の目的は、上述のような磁気検出器
が相対的にＸ方向に移動するときＹ又はＺ方向に位置が
多少変動しても或る区間内では出力に影響しないように
磁気検出器を改良することである。Therefore, an object of the present invention is to prevent the output from being influenced within a certain section even if the position of the magnetic detector as described above moves in the Y or Z direction to some extent when the magnetic detector relatively moves in the X direction. It is to improve the magnetic detector.
本発明は、１対の磁石片を同一又は平行な面内において
対向させた構造の発磁体を使用することにより、上記の
問題点を大幅に改善することができた。According to the present invention, the above-mentioned problems can be remarkably improved by using a magnetizing body having a structure in which a pair of magnet pieces are opposed to each other in the same or parallel plane.
実測により、上記構造の発磁体を用いると、Ｙ及びＺ変
位の或る範囲内で出力電圧の変動が少ないことが認めら
れた。From the actual measurement, it was confirmed that the fluctuation of the output voltage was small within a certain range of the Y and Z displacements when the magnetic body having the above structure was used.
第１図は本発明に用いる発磁体の第１の例を示すもの
で、同図Ａは平面図、同図Ｂは側面図である。本例は、
鉄板又は鉄枠の両端に短冊状の磁石片（例えばゴム磁
石）を図示のように貼り付ける。すなわち、１対の磁石
片M1,M2を同一面上に対向して配置する。この場合、磁
気検出器はＹ方向の磁界ＨＹを検出することになる。FIG. 1 shows a first example of a magnetizing material used in the present invention. FIG. 1A is a plan view and FIG. 1B is a side view. In this example,
Strip-shaped magnet pieces (for example, rubber magnets) are attached to both ends of the iron plate or the iron frame as illustrated. That is, the pair of magnet pieces M 1 and M 2 are arranged so as to face each other on the same surface. In this case, the magnetic detector will detect the magnetic field H Y in the Y direction.
第３図は、第１図の発磁体が生ずる磁界ＨＹの実測例を
示すものである。使用した発磁体の寸法は、長さＬ及び
幅Ｗが共に80ミリ、磁石片の幅が15ミリで厚さが２ミリ
である。この図より、Ｙ変位が±10ミリ、ｄが10〜25ミ
リの範囲では磁界ＨＹの変化はかなり少なくなつている
ことが判る。ここで、エレベータの場合を考えると、エ
レベータはロープで吊り下げられているので水平面（YZ
面）での揺れが避けられないが、Ｙ及びＺ方向の揺れ許
容値を±10ミリとすれば、発磁体の生ずる磁界がこの範
囲でほぼ一定（不変）であればよいことになる。FIG. 3 shows an example of actual measurement of the magnetic field H Y generated by the magnetism generating body shown in FIG. Regarding the size of the magnetized body used, the length L and the width W are both 80 mm, the width of the magnet piece is 15 mm, and the thickness is 2 mm. From this figure, it can be seen that the change in the magnetic field H Y is considerably small when the Y displacement is ± 10 mm and d is in the range of 10 to 25 mm. Considering the case of an elevator, the elevator is suspended by a rope, so the horizontal plane (YZ
It is inevitable that the magnetic field generated by the magnet will be constant (invariant) within this range if the permissible value of fluctuation in the Y and Z directions is ± 10 mm.
第４図は、Ｙ変位を０としｄを10〜35ミリの範囲で変え
たときの出力電圧を示すもので、ｄ＝10〜25ミリの範囲
では出力が殆ど変わらないことが判る。FIG. 4 shows the output voltage when Y displacement is set to 0 and d is changed in the range of 10 to 35 mm, and it can be seen that the output hardly changes in the range of d = 10 to 25 mm.
第５図は、ｄ＝20（一定）としＹ変位を０〜±15ミリの
範囲で変えたときの出力電圧を示すもので、この範囲で
は出力電圧が殆ど不変である。すなわち、第１図の発磁
体による改善効果が明らかである。FIG. 5 shows the output voltage when d displacement is 20 (constant) and the Y displacement is changed in the range of 0 to ± 15 mm, and the output voltage is almost unchanged in this range. That is, the improvement effect by the magnetism generating body of FIG. 1 is clear.
なお、第１図には、鉄板（又は鉄枠）にゴム磁石を貼り
付けた発磁体の例を示したが、非磁性体の板（又は枠）
を用いてもよい。Note that FIG. 1 shows an example of a magnetizing body in which a rubber magnet is attached to an iron plate (or an iron frame), but a nonmagnetic plate (or frame) is shown.
May be used.
第２図は、本発明に用いうる発磁体の第２の例を示すも
ので、同図Ａは平面図、同図Ｂは側面図である。本例
は、断面コ字形の鉄枠に上記と同様な磁石片を貼り付け
たもので、１対の磁石片M1,M2を互いに平行な面内に対
向させて配置している。本例は、形状が平面的な第１図
の例より扱いにくいが、発磁体の性能からみるとこちら
の方が勝れている。FIG. 2 shows a second example of a magnetic body that can be used in the present invention. FIG. 2A is a plan view and FIG. 2B is a side view. In this example, a magnet piece similar to the above is attached to an iron frame having a U-shaped cross section, and a pair of magnet pieces M 1 and M 2 are arranged to face each other in parallel planes. This example is more difficult to handle than the example of FIG. 1 in which the shape is flat, but this is superior from the viewpoint of the performance of the magnetic body.
第６図は、第２図の発磁体が生ずる磁界ＨＹの状態を示
すものである。この場合の発磁体の寸法は、長さＬが10
0ミリ、幅Ｗが80ミリ、鉄枠の高さＨが40ミリ、磁石片
の幅が15ミリである。FIG. 6 shows the state of the magnetic field H Y generated by the magnetism generating body shown in FIG. In this case, the length of the magnetized body is 10
The width is 0 mm, the width W is 80 mm, the height H of the iron frame is 40 mm, and the width of the magnet piece is 15 mm.
第７図は、Ｙ＝０としｄを10〜40ミリの範囲で変えたと
きの出力電圧を示すもので、ｄ＝20〜35ミリの範囲では
殆ど出力に差がない。FIG. 7 shows the output voltage when Y = 0 and d is changed in the range of 10 to 40 mm, and there is almost no difference in the output in the range of d = 20 to 35 mm.
第８図は、エレベータの停止位置制御に適した磁気検出
器の出力特性を示すもので、直線から若干ずれた形状を
している。第９図（従来）の可飽和コイルは４個であつ
たが、可飽和コイルの数を増加することにより所望の形
状の出力電圧曲線を得ることが可能である。同図に示す
ような出力特性を得るためには、長さ500ミリの磁気検
出器が必要になるが、可飽和コイル４個では実現が難し
く、８個の可飽和コイルを４個ずつ組にして良好な結果
を得た。また、可飽和コイルの間隔は一定でなく、発磁
体の幅より狭い間隔でよいこともある。FIG. 8 shows the output characteristic of a magnetic detector suitable for elevator stop position control, and has a shape slightly deviated from a straight line. Although the number of saturable coils in FIG. 9 (conventional) is four, an output voltage curve having a desired shape can be obtained by increasing the number of saturable coils. To obtain the output characteristics shown in the figure, a magnetic detector with a length of 500 mm is required, but it is difficult to realize with four saturable coils, and eight saturable coils are grouped in groups of four. And obtained good results. In addition, the space between the saturable coils is not constant, and the space may be smaller than the width of the magnet.
以上説明したとおり、本発明によれば、磁気検出器の発
磁体に対する相対的変位方向と直角な方向に位置ずれが
生じても、磁気検出器の性能に影響せず、また、可飽和
コイルの数を増加することにより希望する関数形の出力
電圧を得ることができるので、エレベータ等の如く昇降
の際に揺れが避けられず且つ直線より若干ずれた出力特
性曲線が好ましい搬送車の停止制御用の位置検出器とし
て最適である。As described above, according to the present invention, even if the positional deviation occurs in the direction perpendicular to the relative displacement direction of the magnetic detector with respect to the magnet body, the performance of the magnetic detector is not affected, and the saturable coil Since it is possible to obtain the desired function output voltage by increasing the number, it is necessary to control the stop of the transport vehicle, such as an elevator, where swaying is inevitable when going up and down and an output characteristic curve that is slightly deviated from the straight line is preferable. It is most suitable as a position detector.
第１及び第２図はそれぞれ本発明に用いられる発磁体の
第１及び第２の例を示す図、第３図は第１図の発磁体が
生ずる磁界ＨＹを示す実測図、第４図は第１図の発磁体
を用いＹを０、ｄを可変としたときの出力電圧曲線図、
第５図は第１図の発磁体を用いｄを一定、Ｙを可変とし
たときの出力電圧曲線図、第６図は第２図の発磁体が生
ずる磁界ＨＹを示す実測図、第７図は第２図の発磁体を
用いＹ＝０、ｄを可変としたときの出力電圧曲線図、第
８図はエレベータの停止位置制御に適した出力電圧曲線
図、第９図は前の磁気検出器の基本構成図、第10図は第
９図の磁気検出器の出力電圧曲線図、第11図は第９図の
発磁体と磁気検出器の相対的位置関係を示す図、第12図
は可飽和コイルの特性を示す図（その１）、第13図は可
飽和コイルの特性を示す図（その２）である。 M1,M2……１対の磁石片、Ｍ……発磁体、Ｗ……発磁体
の幅、L1,L2,L3,L4……可飽和コイル、Ｒｓ……抵抗、O
SC……発振器、（D1,D2,R1,R2,C1,C2,C3）……差動出力
取出し手段。FIGS. 1 and 2 are diagrams showing first and second examples of a magnetic body used in the present invention, and FIG. 3 is an actual measurement diagram showing a magnetic field H Y generated by the magnetic body of FIG. 1, and FIG. Is an output voltage curve diagram when Y is 0 and d is variable using the magnetizer of FIG.
FIG. 5 is an output voltage curve diagram when d is constant and Y is variable using the magnetic body of FIG. 1, and FIG. 6 is an actual measurement diagram showing a magnetic field H Y generated by the magnetic body of FIG. Fig. 8 is an output voltage curve diagram when Y = 0 and d is variable using the magnetizer of Fig. 2, Fig. 8 is an output voltage curve diagram suitable for elevator stop position control, and Fig. 9 is the previous magnetic field. Fig. 10 is a basic configuration diagram of the detector, Fig. 10 is an output voltage curve diagram of the magnetic detector of Fig. 9, and Fig. 11 is a diagram showing the relative positional relationship between the magnetizer and the magnetic detector of Fig. 9, Fig. 12. Is a diagram showing the characteristics of the saturable coil (No. 1), and FIG. 13 is a diagram showing the characteristics of the saturable coil (No. 2). M 1 , M 2 ...... a pair of magnet pieces, M ...... magnetizer, W …… magnetizer width, L 1 , L 2 , L 3 , L 4 …… saturable coil, R s …… resistance, O
SC: Oscillator, (D 1 , D 2 , R 1 , R 2 , C 1 , C 2 , C 3 ): Differential output extraction means.
Claims (1)
て対向させた構造の発磁体と、 この発磁体の幅以上の区間にわたり直線上に配列した偶
数個の可飽和コイルと、 これらの可飽和コイルを２組に分け各組の可飽和コイル
にそれぞれ抵抗を介して高周波電圧を供給する発振器
と、 上記各抵抗に生じる電圧を整流して差動的に取出す手段
とを具え、 上記発磁体が上記可飽和コイルに対して相対的に変位し
たとき、変位方向と直角な方向の位置ずれに無関係な所
望の出力電圧を生じることを特徴とする磁気検出器。1. A magnetizing body having a structure in which a pair of magnet pieces are opposed to each other in the same or parallel plane, and an even number of saturable coils arranged in a straight line over a section equal to or larger than the width of the magnetizing body. The saturable coils of 2 are divided into two sets, and each set of saturable coils is supplied with a high frequency voltage via a resistor, and a means for rectifying the voltage generated in each of the resistors to differentially extract the voltage. A magnetic detector characterized in that, when a magnetized body is displaced relative to the saturable coil, a desired output voltage is produced irrespective of displacement in a direction perpendicular to the displacement direction.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28351486A JPH0739923B2 (en) | 1986-11-28 | 1986-11-28 | Magnetic detector |
| US07/006,439 US4788498A (en) | 1986-01-28 | 1987-01-23 | Magnetic detector for an unmanned vehicle control system |
| CA000528250A CA1265596A (en) | 1986-01-28 | 1987-01-27 | Magnetic detector |
| EP87300744A EP0242940B1 (en) | 1986-01-28 | 1987-01-28 | Magnetic detector |
| DE8787300744T DE3777435D1 (en) | 1986-01-28 | 1987-01-28 | MAGNETIC DETECTOR. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28351486A JPH0739923B2 (en) | 1986-11-28 | 1986-11-28 | Magnetic detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63135806A JPS63135806A (en) | 1988-06-08 |
| JPH0739923B2 true JPH0739923B2 (en) | 1995-05-01 |
Family
ID=17666524
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28351486A Expired - Lifetime JPH0739923B2 (en) | 1986-01-28 | 1986-11-28 | Magnetic detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0739923B2 (en) |
-
1986
- 1986-11-28 JP JP28351486A patent/JPH0739923B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63135806A (en) | 1988-06-08 |
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