JPH09236642A - Magnetic substance detecting device - Google Patents
Magnetic substance detecting deviceInfo
- Publication number
- JPH09236642A JPH09236642A JP8045699A JP4569996A JPH09236642A JP H09236642 A JPH09236642 A JP H09236642A JP 8045699 A JP8045699 A JP 8045699A JP 4569996 A JP4569996 A JP 4569996A JP H09236642 A JPH09236642 A JP H09236642A
- Authority
- JP
- Japan
- Prior art keywords
- coil
- open ends
- core
- magnetic substance
- magnetic
- 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
- Measuring Magnetic Variables (AREA)
- Geophysics And Detection Of Objects (AREA)
- Inspection Of Paper Currency And Valuable Securities (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は紙葉類等の印刷に使
用されるインキに含まれる微量の磁性体を検知する磁性
体検出装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic substance detecting device for detecting a very small amount of magnetic substance contained in ink used for printing paper sheets and the like.
【０００２】[0002]
【従来の技術】紙葉類の印刷に使用されるインキに含ま
れる磁性体を検知することにより紙葉類を識別する方法
は広く知られている。従来、この紙葉類の印刷に使用さ
れた磁性体の検知装置には、Ｓ字型のコアの中央部に一
次巻線を設け、微小な間隙に設定した２箇所の開口部側
のそれぞれに２次巻線を巻いて一方の開口部上に紙葉類
を通過させ、２つの２次巻線の誘起電圧の差を出力とす
る差動巻線形トランス方式や、巻線を設けた環状のコア
の一部に微小な間隙を設けて間隙上を磁性体が通過する
際の環状コアのインピーダンスの変化を検出する方式等
がある。2. Description of the Related Art A method of identifying a paper sheet by detecting a magnetic substance contained in ink used for printing the paper sheet is widely known. Conventionally, in a magnetic substance detection device used for printing paper sheets, a primary winding is provided in the center of an S-shaped core, and two openings are provided on each side of the opening, which are set to have a minute gap. A differential winding type transformer system in which a secondary winding is wound and paper sheets are passed through one of the openings to output the difference between the induced voltages of the two secondary windings, or a circular winding with a winding is provided. There is a method in which a minute gap is provided in a part of the core and a change in impedance of the annular core is detected when a magnetic material passes through the gap.
【０００３】また、磁性体に対して非接触な状態で検知
する方式としては、特開昭５９−１４１０５８号公報に
開示されたように、２個のコの字形のコアを間隙をもっ
て対向させ、各々のコアに巻線を巻いて直列に接続し
て、間隙間を磁性体が通過する際のインピーダンスの変
化を検出する方法がある。As a method for detecting the magnetic substance in a non-contact state, as disclosed in JP-A-59-141058, two U-shaped cores are made to face each other with a gap, There is a method in which a winding is wound around each core and connected in series to detect a change in impedance when a magnetic body passes through a gap.
【０００４】[0004]
【発明が解決しようとする課題】差動巻線型トランス方
式や環状コアインピーダンス方式では、コアの間隙上を
磁性体が接触しながら通過する時に検出信号が最大とな
り、コアと磁性体の距離が離れると信号出力は急激に減
少する。従って磁性体が揺動しながら通過すると検出信
号も変動してしまう。また、コアの間隙以上にコアと磁
性体の距離が離れてしまうと検出信号はほとんど零にな
ってしまう。In the differential winding type transformer system and the annular core impedance system, the detection signal becomes maximum when the magnetic material passes through the gap of the core while coming into contact with the core, and the distance between the core and the magnetic material increases. And the signal output decreases sharply. Therefore, when the magnetic body passes while swinging, the detection signal also fluctuates. Further, if the distance between the core and the magnetic body is larger than the gap between the cores, the detection signal becomes almost zero.
【０００５】このように、コアと磁性体との距離の影響
を受け易く、また紙葉類を高速搬送する場合には紙葉類
の振動も激しくなるため安定した検出信号を得ることが
困難である。As described above, the distance between the core and the magnetic material is easily affected, and when the paper sheet is conveyed at a high speed, the vibration of the paper sheet becomes severe and it is difficult to obtain a stable detection signal. is there.
【０００６】また上述した特開昭５９−１４１０５８号
公報に開示された非接触検知方式では、コの字形コアの
対向部のどちらか或は両方に磁性体がある場合に検出信
号が得られる。しかし磁性体の量が同じ場合、対向部の
両方に磁性体があるときの検出信号は対向部の片方にの
み磁性体がある場合の倍の大きさとなるなど、磁性体の
量の特定は困難であった。また、磁性体が対向部のどち
らかにあっても検出信号が得られるため場所の特定は出
来なかった。さらには周波温度の変化によりコアの透磁
率が変わるため検出信号が変動しやすかった。In the non-contact detection method disclosed in Japanese Patent Laid-Open No. 59-141058, a detection signal is obtained when a magnetic material is present in either or both of the facing portions of the U-shaped core. However, when the amount of magnetic material is the same, the detection signal when there is a magnetic material in both facing parts is twice as large as when there is a magnetic material in only one facing part, making it difficult to specify the amount of magnetic material. Met. In addition, it was not possible to specify the location because the detection signal was obtained even if the magnetic material was in either of the facing portions. Further, the magnetic permeability of the core changes with the change of frequency temperature, so that the detection signal is easily changed.
【０００７】そこで本発明では、コアと磁性体との距離
が変動しても検出信号の変動が少なく、磁性体の量に比
例した検出信号が得られ、場所の特定が可能で、温度変
化にも安定な磁性体検出装置の提供を目的とする。Therefore, according to the present invention, even if the distance between the core and the magnetic material varies, the variation of the detection signal is small, a detection signal proportional to the amount of the magnetic material can be obtained, the location can be specified, and the temperature can be changed. Another object is to provide a stable magnetic substance detection device.
【０００８】[0008]
【課題を解決するための手段】上記の目的を達成するた
めに本発明においては、２つの異なる長さの開放端を有
し、その長い開放端同志および短い開放端同志を所定間
隙をもって対向させてなる一対のコアと、前記長い開放
端同志を直列に接続してなる第１のコイルと、前記短い
開放端同志を直列に接続してなる第２のコイルと、前記
第１のコイルからの検出信号と前記第２のコイルからの
検出信号とを処理する処理回路とを具備してなる磁性体
検出装置とした。In order to achieve the above object, the present invention has two open ends having different lengths, and the long open end and the short open end are opposed to each other with a predetermined gap. From a pair of cores, a first coil formed by connecting the long open ends to each other in series, a second coil formed by connecting the short open ends to each other in series, and The magnetic substance detection device is provided with a processing circuit for processing the detection signal and the detection signal from the second coil.
【０００９】なお、前記コアはアモルファス箔を積層し
て構成されていることが好ましい。また、前記コアの前
記開放端間の距離ｗを前記コアの厚さの２倍以上に設定
すること、前記コアの前記開放端の長さの差Ｐを前記長
い開放端同志の隙間Ｇの１／３以上に設定すること、前
記コアの前記開放端の間隔ｄを前記長い開放端同志の間
隙Ｇの１／２以上に設定することがそれぞれ好ましい。It is preferable that the core is formed by laminating amorphous foils. Further, the distance w between the open ends of the core is set to be twice or more the thickness of the core, and the difference P in the length of the open ends of the core is set to 1 of the gap G between the long open ends. It is preferable to set it to / 3 or more, and to set the distance d between the open ends of the core to 1/2 or more of the gap G between the long open ends.
【００１０】また、上記のように構成された磁性体検出
装置を、その各コアの開放端を結ぶ線が略平行となるよ
うに複数個並設して磁性体検出装置を形成してもよい。
その際、前記コア同志の間隔ｓを、前記長い開放端同志
の間隔Ｇ以上に設定することが好ましい。Further, a plurality of magnetic substance detecting devices configured as described above may be arranged side by side so that the lines connecting the open ends of the respective cores are substantially parallel to each other to form the magnetic substance detecting device. .
At that time, it is preferable to set the interval s between the cores to be equal to or more than the interval G between the long open ends.
【００１１】このように構成された本発明によれば、コ
アの開放端を対向させて各々の開放端のコイルを直列に
接続しているため、間隙内での磁性体の位置によるコイ
ルのインピーダンス値の変動は小さく非接触での検知が
可能である。また、コアの長い開放端を対向させた間隙
部は磁性体に感応して検出信号を出力するが、短い開放
端を対向させた間隙部は間隔が大きいため磁性体にはわ
ずかしか感応しない。したがって、対向するコイル同志
のインピーダンスの差を検出することにより温度による
変動が相殺され、磁性体の量に比例した信号を得ること
ができる。According to the present invention thus constructed, the open ends of the cores are opposed to each other and the coils at the open ends are connected in series. Therefore, the impedance of the coil depending on the position of the magnetic substance in the gap. The fluctuation of the value is small and it is possible to detect without contact. Further, the gap portion with the long open end of the core facing is sensitive to the magnetic substance and outputs a detection signal, but the gap portion with the short open end facing is very sensitive to the magnetic substance because the gap is large. Therefore, by detecting the difference in impedance between the coils facing each other, the variation due to temperature is offset, and a signal proportional to the amount of magnetic material can be obtained.
【００１２】[0012]
【発明の実施の形態】以下、図面を参照して本発明の実
施例を詳細に説明する。図１は、本発明の一実施例に係
る磁性体検出装置の構成図である。1 は検出部で、この
検出部1 はＪ字形のコア2,5 と、コイル3,4,6,7 とから
構成されている。また8 は磁性体粉末等を含んだ磁性イ
ンキで印刷された紙葉類である。BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a configuration diagram of a magnetic body detection device according to an embodiment of the present invention. Reference numeral 1 is a detection unit, which is composed of J-shaped cores 2, 5 and coils 3, 4, 6, 7. Further, 8 is a paper sheet printed with a magnetic ink containing magnetic powder and the like.
【００１３】コア2,5 は、本実施例ではアモルファス箔
を積層して構成されている。コア2の長い開放端2aには
コイル3 が、短い開放端2bにはコイル4 がそれぞれ巻回
されており、もう一方のコア5 の長い開放端5a付近には
コイル6 が、短い開放端5b付近にはコイル7 がそれそれ
巻回されている。In this embodiment, the cores 2 and 5 are formed by laminating amorphous foils. The coil 3 is wound around the long open end 2a of the core 2, and the coil 4 is wound around the short open end 2b.The coil 6 is wound around the long open end 5a of the other core 5, and the short open end 5b is wound around it. Coil 7 is wound around in the vicinity.
【００１４】コア2 とコア3 の長い開放端2a,5a 同志
と、短い開放端2b,5b 同志とは、所定間隙をもって対向
配置されており、長い開放端2a,5a に巻装したコイル3,
6 を直列に接続してコイル100 が構成され、短い開放端
2b,5b に巻装したコイル4,7 を直列に接続してコイル20
0 が構成される。The long open ends 2a and 5a of the core 2 and the core 3 and the short open ends 2b and 5b of the core 2 and the core 3 are arranged to face each other with a predetermined gap, and the coils 3 and 5 wound around the long open ends 2a and 5a.
Coil 100 is constructed by connecting 6 in series and has a short open end.
Connect coils 4 and 7 wound around 2b and 5b in series to
0 is configured.
【００１５】コイル100 を付勢した際にコイル3,4 に発
生する磁力線は、コア2,5 の対向する間隙内では例えば
矢印Ａの方向に一致させてある。コイル200 においても
同様に、コア2 の開放端2bとコア5 の開放端5b間の磁力
線の方向は矢印Ｂの方向に一致させてある。また、矢印
Ａと矢印Ｂが反対向きになるようにして、コア2 とコア
5 で構成する２箇所の間隙を含む環状磁路内で磁力線の
方向が同一となるように設定する。The magnetic lines of force generated in the coils 3 and 4 when the coil 100 is energized are aligned in the direction of arrow A, for example, in the gaps between the cores 2 and 5 facing each other. Similarly, in the coil 200, the direction of the line of magnetic force between the open end 2b of the core 2 and the open end 5b of the core 5 is aligned with the direction of arrow B. Also, make sure that arrow A and arrow B are in opposite directions,
Set so that the directions of the lines of magnetic force are the same in the annular magnetic path that includes the two gaps formed by 5.
【００１６】コア2 とコア5 の間隙内に磁性体粉等を含
む磁性インキで印刷された紙葉類８が挿入されると、間
隙内の磁力線の分布が変化するためコイル100 およびコ
イル200 のインピーダンスが変化する。但し、開放端2
b,5b の間隙は開放端2a,5a 間の間隙Ｇに比して広いた
め、紙葉類8 による磁力線の変化量は少なく、コイル20
0 のインピーダンスの変化も小さい。したがって、紙葉
類8 の磁気インキは開放端2a,5a の間隙Ｇ内にある部分
がコイル100 によって検知される。When a paper sheet 8 printed with a magnetic ink containing magnetic powder or the like is inserted into the gap between the core 2 and the core 5, the distribution of magnetic lines of force in the gap changes, so that the coil 100 and the coil 200 are separated. Impedance changes. However, open end 2
Since the gap between b and 5b is wider than the gap G between the open ends 2a and 5a, the amount of change in the lines of magnetic force due to the paper sheet 8 is small and the coil 20
The change in impedance at 0 is also small. Therefore, the magnetic ink of the paper sheet 8 is detected by the coil 100 at the portion in the gap G between the open ends 2a and 5a.
【００１７】もし、紙葉類8 が矢印Ｃの方向に移動すれ
ば、紙葉類8 の移動方向に分布する磁気インキは開放端
2a,5a の間隙内での磁気インキ量の変化に伴うコイル10
0 のインピーダンスの変化として検知できる。If the paper sheet 8 moves in the direction of arrow C, the magnetic ink distributed in the moving direction of the paper sheet 8 will have an open end.
Coil 10 with changes in the amount of magnetic ink in the gap 2a, 5a
It can be detected as a change in impedance of 0.
【００１８】一方、検出部1 の周囲温度が変化するとコ
ア2 およびコア5 の透磁率が変化し、コイル100 および
コイル200 のインピーダンスが変化する。コイル100 と
コイル200 との周囲温度は概略同一であることから、温
度変化によるインピーダンスの増減の方向も同じであ
る。従ってコイル100 とコイル200 のインピーダンスの
差をとれば、温度によるインピーダンスの変化分は消去
され磁性体によるインピーダンスの変化分のみを取り出
すことができる。On the other hand, when the ambient temperature of the detecting section 1 changes, the magnetic permeability of the cores 2 and 5 changes, and the impedances of the coils 100 and 200 change. Since the ambient temperatures of the coil 100 and the coil 200 are substantially the same, the directions of increase and decrease in impedance due to temperature changes are also the same. Therefore, if the difference in impedance between the coil 100 and the coil 200 is taken, the change in impedance due to temperature is erased and only the change in impedance due to the magnetic material can be extracted.
【００１９】次に、開放端2a,5a 間の間隙Ｇ内で紙葉類
8 の位置変化による影響について述べる。紙葉類8 が間
隙Ｇの中間にある場合はコイル3 とコイル6 のインピー
ダンスの変化量が同じであるが紙葉類8 が開放端2aに近
づくとコイル3 のインピーダンスは増大しコイル6 のイ
ンピーダンスは減少する。また紙葉類8 が開放端5aに近
づくとコイル6 のインピーダンスは増大しコイル3 のイ
ンピーダンスは減少する。しかしコイル100 はコイル3
とコイル6 を直列に接続しているため、２つのコイル3,
6 のインピーダンスの増加量と減少量とが打ち消し合
い、結果として変化量は小さくなる。従って、紙葉類8
が開放端2a,5a の間隙Ｇ間内で揺動しても検出信号への
影響は小さい。Next, in the gap G between the open ends 2a and 5a, the paper sheets are
The effects of position changes in 8 are described below. When the paper sheet 8 is in the middle of the gap G, the change amounts of the impedances of the coil 3 and the coil 6 are the same, but when the paper sheet 8 approaches the open end 2a, the impedance of the coil 3 increases and the impedance of the coil 6 increases. Decreases. When the paper sheet 8 approaches the open end 5a, the impedance of the coil 6 increases and the impedance of the coil 3 decreases. But coil 100 is coil 3
And the coil 6 are connected in series, the two coils 3,
The increase and decrease of impedance of 6 cancel each other out, resulting in a smaller change. Therefore, paper sheets 8
Even if oscillates within the gap G between the open ends 2a and 5a, the influence on the detection signal is small.
【００２０】以上、検出部1 の構成とその動作について
述べたが、開放端2b,5b の間隙内の磁力線の方向が矢印
Ｂと反対の場合や、開放端2a,5a の間隙Ｇ内でのコイル
3,6の磁力線の方向と開放端2b,5b の間隙内でのコイル
4,7 の磁力線の方向とが互いに反対向きの場合でも、本
発明の効果が維持されることは言うまでもない。The structure of the detector 1 and its operation have been described above. When the direction of the magnetic lines of force in the gap between the open ends 2b and 5b is opposite to the arrow B or in the gap G between the open ends 2a and 5a. coil
Coil in the direction of magnetic field lines 3 and 6 and in the gap between open ends 2b and 5b
It goes without saying that the effect of the present invention is maintained even when the directions of the magnetic lines of force 4 and 7 are opposite to each other.
【００２１】また、コア2,5 はアモルファス箔以外の磁
性材料で構成することも可能であるが、アモルファス箔
のような高透磁率の材料を用いることにより、磁力線の
広がりを小さくできるためコア開放部の対向間隙Ｇを大
きくすることができる。Although the cores 2 and 5 can be made of a magnetic material other than the amorphous foil, the use of a material having a high magnetic permeability such as the amorphous foil can reduce the spread of the magnetic force lines and thus open the core. The facing gap G of the part can be increased.
【００２２】図２はコア2 の外形を示す斜視図である。
コア2 の幅ｗは厚さｔの２倍以上に大きく設定して紙葉
類8 の移動方向と直交する方向に一定の幅を持たせ、厚
さｔを薄くして磁力線の厚みを小さくし移動方向の磁性
体の分布の変化を精度良く検出するものである。コイル
3,4 は開放端2a,2b に近い位置に設置されており、開放
端部の磁力線の変動を感度よく検出することができるよ
うになっている。開放端2a,2b の間隔ｄは図１の開放端
2a,5a の間隙距離Ｇ以上にすることが開放端2bの影響を
小さくできるため望ましいが、実験の結果では間隔ｄ＝
Ｇ／２でも磁性体の検知が可能であった。紙葉類8 が開
放端2a上にあっても開放端2bのコイル4は紙葉類8 の磁
性体に感応しないのが望ましいため、コア2 の開放端2
a,2b の差Ｐは間隙Ｇ以上が好ましいが、実験の結果で
はＰ＝Ｇ／３としてもコイル4 の影響は見られなかっ
た。FIG. 2 is a perspective view showing the outer shape of the core 2.
The width w of the core 2 is set to be twice as large as the thickness t or more so as to have a constant width in the direction orthogonal to the moving direction of the paper sheet 8, and the thickness t is reduced to reduce the thickness of the magnetic force line. The change in the distribution of the magnetic material in the moving direction is detected with high accuracy. coil
3 and 4 are installed close to the open ends 2a and 2b, and it is possible to detect the fluctuation of the magnetic field lines at the open ends with high sensitivity. The distance d between the open ends 2a and 2b is the open end in FIG.
It is desirable to set the gap distance G of 2a, 5a or more to the extent that the influence of the open end 2b can be reduced.
The magnetic substance could be detected even in G / 2. Even if the paper sheet 8 is on the open end 2a, it is desirable that the coil 4 of the open end 2b should not be sensitive to the magnetic material of the paper sheet 8, so the open end 2 of the core 2
The difference P between a and 2b is preferably equal to or larger than the gap G, but the experimental result shows that the effect of the coil 4 is not found even if P = G / 3.
【００２３】図３は、図１に示した検出部1 の信号処理
回路を示すブロック図である。13は検出部1 のコイル10
0,200 を構成要素としたブリッジ回路で、R1,R2 はブリ
ッジ回路構成用の辺抵抗、VR1,VR2 はブリッジ回路のバ
ランス調整用の可変抵抗器である。また、14は発振回路
でブリッジ回路を付勢する15は差動アンプ、16は位相同
期検波回路、17は位相設定回路、18はフィルタ回路であ
る。FIG. 3 is a block diagram showing a signal processing circuit of the detector 1 shown in FIG. 13 is the coil 10 of the detector 1
A bridge circuit with 0,200 components, R1 and R2 are side resistors for bridge circuit construction, and VR1 and VR2 are variable resistors for balancing the bridge circuit. Further, 14 is an oscillating circuit for activating the bridge circuit, 15 is a differential amplifier, 16 is a phase synchronous detection circuit, 17 is a phase setting circuit, and 18 is a filter circuit.
【００２４】ブリッジ回路13では、差動アンプ15の出力
波形の振幅が出来るだけ小さくなるようにVR1,VR2 を調
整しておく。コイル100 のインピーダンスが変化すると
差動アンプ15の出力波形と振幅が変化する。位相同期検
波回路16は位相設定回路17で設定された位相のもとで差
動アンプ15からの信号を検波整流する。位相設定回路17
は発振回路14からの入力波形に対して設定された位相だ
けずれた信号を位相同期検波回路16に送るもので、設定
位相は、例えば検出部1 内に検出対象が置かれたときに
ブリッジ回路13の出力が最大になるように設定する。ま
た、この位相設定においては、検出信号に対し有害とな
る雑音成分が最小となるようにしてもよい。低域通過用
のフィルタ回路18は位相同期検波回路16で検波された信
号を高周波成分を除去する。また、フィルタ回路18に
は、出力信号の電圧レベルを変える機能を持たせてもよ
い。In the bridge circuit 13, VR1 and VR2 are adjusted so that the amplitude of the output waveform of the differential amplifier 15 is as small as possible. When the impedance of the coil 100 changes, the output waveform and amplitude of the differential amplifier 15 change. The phase synchronous detection circuit 16 detects and rectifies the signal from the differential amplifier 15 based on the phase set by the phase setting circuit 17. Phase setting circuit 17
Is a signal sent to the phase-coherent detection circuit 16 with a phase offset from the input waveform from the oscillation circuit 14, and the set phase is, for example, a bridge circuit when a detection target is placed in the detection unit 1. Set the output of 13 to the maximum. Further, in this phase setting, the noise component harmful to the detection signal may be minimized. The low-pass filter circuit 18 removes high-frequency components from the signal detected by the phase-locked detection circuit 16. Further, the filter circuit 18 may have a function of changing the voltage level of the output signal.
【００２５】図４は検出部1 の信号処理回路の他の実施
例を示すブロック図である。19は検出部1 のコイル100,
200 を構成要素とするブリッジ回路でR1,R2 はブリッジ
回路構成用の辺抵抗、VR1 はブリッジ回路のバランス調
整用の可変抵抗器である。20は矩形波発振回路、21は差
動アンプ、22,23 はサンプルホールド回路、24は周波数
低減回路、25は差動アンプ、26はフィルタ回路である。
矩形発振回路20の出力波形を周波数低減回路24で例えば
１／100 の周波数の矩形波に低減してブリッジ回路19を
付勢する。ブリッジ回路19はVR1 により差動アンプ21の
出力振幅が最適な状態になるよう調整しておく。周波数
低減回路24は例えば10進カウンタ回路等により構成し
て、低減波形を発生すると共にカウントパルス結果を出
力する機能を利用して、位相設定をパルスのカウント数
で行い、設定位相に相当するタイミングでサンプリング
パルスをサンプルホールド回路22,23 に出力する。差動
アンプ21の正側の波形をサンプルホールド回路22でサン
プルし次のサンプリングパルスまでサンプルした電圧を
ホールドする。負側の波形のサンプリングはサンプルホ
ールド回路23で行い同様にサンプリングした電圧をホー
ルドする。差動アンプ25で正側、負側のサンプル電圧を
例えば正側にのみ極性変換し、低減通過用のフィルタ回
路26により高周波成分を除去して信号を出力する。ま
た、フィルタ回路26には、出力信号の電圧レベルを変え
る機能を持たせても良い。FIG. 4 is a block diagram showing another embodiment of the signal processing circuit of the detector 1. 19 is the coil 100 of the detector 1,
In the bridge circuit consisting of 200, R1 and R2 are side resistors for bridge circuit configuration, and VR1 is a variable resistor for adjusting the balance of the bridge circuit. Reference numeral 20 is a rectangular wave oscillation circuit, 21 is a differential amplifier, 22 and 23 are sample hold circuits, 24 is a frequency reduction circuit, 25 is a differential amplifier, and 26 is a filter circuit.
The output waveform of the rectangular oscillator circuit 20 is reduced to a rectangular wave having a frequency of, for example, 1/100 by the frequency reduction circuit 24, and the bridge circuit 19 is energized. The bridge circuit 19 is adjusted by VR1 so that the output amplitude of the differential amplifier 21 is in an optimum state. The frequency reduction circuit 24 is composed of, for example, a decimal counter circuit, and uses the function of generating a reduced waveform and outputting the count pulse result, and the phase is set by the pulse count number, and the timing corresponding to the set phase is set. Outputs the sampling pulse to the sample and hold circuits 22 and 23. The positive side waveform of the differential amplifier 21 is sampled by the sample hold circuit 22, and the sampled voltage is held until the next sampling pulse. The sampling of the negative waveform is performed by the sample hold circuit 23, and the sampled voltage is held in the same manner. The differential amplifier 25 polarizes the positive and negative sample voltages only to, for example, the positive side, and a reduction pass filter circuit 26 removes high frequency components and outputs a signal. Further, the filter circuit 26 may have a function of changing the voltage level of the output signal.
【００２６】図５は、図１に示した検出部1 を複数個並
べてなる磁性体検出装置を示す側面図である。なお、上
述した実施例と同一構成要素には同一符号を付して重複
する説明を省略する。FIG. 5 is a side view showing a magnetic substance detecting device in which a plurality of detecting portions 1 shown in FIG. 1 are arranged. In addition, the same components as those in the above-described embodiment are designated by the same reference numerals, and duplicate description will be omitted.
【００２７】本実施例において10はコア2,5 を支える支
持具で非磁性体から構成される。検出部1 の間隔Ｓは、
隣接する検出部1 同志の干渉を小さくするため、コア2
とコア5 との間隙Ｇに対し同じかそれ以上に設定するこ
とが望ましい。In the present embodiment, 10 is a supporting member for supporting the cores 2 and 5, which is made of a non-magnetic material. The interval S between the detectors 1 is
Adjacent detectors 1 Core 2 to reduce mutual interference
It is desirable to set the gap G between the core 5 and the core 5 to be equal to or more than that.
【００２８】図６は図５に示した磁性体検出装置の斜視
図で、支持具9 は検出部支持端11に固定されるものであ
る。なお、本発明は上記実施例に限定されるものではな
く、その主旨を逸脱しない範囲で種々変形して実施する
ことが可能である。例えば、コアはＪ字形の場合につい
て説明したが、コアの開放端の磁性体の差を検出信号と
するのであれば、コアをＵ字形としても良い。また、図
１に示した検出部1 の実施例において、コア2,5 それぞ
れに励磁用コイルを設けて直列に接続してコイル3 と
し、このコイル3 を付勢してコイル100 とコイル200 の
出力の差を差動アンプにより得るか、コイル100 とコイ
ル200 とを差動接続して誘起電圧の差として位相同期検
波することによっても同様な結果が得られる。FIG. 6 is a perspective view of the magnetic substance detecting device shown in FIG. 5, in which the supporting member 9 is fixed to the detecting portion supporting end 11. The present invention is not limited to the above embodiments, and various modifications can be carried out without departing from the spirit of the present invention. For example, the case where the core is J-shaped has been described, but the core may be U-shaped if the difference between the magnetic bodies at the open ends of the core is used as the detection signal. Further, in the embodiment of the detecting unit 1 shown in FIG. 1, each of the cores 2 and 5 is provided with an exciting coil and connected in series to form a coil 3, and this coil 3 is energized to make the coil 100 and the coil 200 Similar results can be obtained by obtaining the output difference by a differential amplifier or by differentially connecting the coil 100 and the coil 200 and performing phase-coherent detection as the difference in induced voltage.
【００２９】[0029]
【発明の効果】以上説明したように本発明によれは、コ
アと磁性体との距離が変動しても検出信号の変動が少な
く、磁性体の量に比例した検出信号が得られ、場所の特
定が可能で、温度変化にも安定な磁性体検出装置が提供
される。As described above, according to the present invention, even if the distance between the core and the magnetic material varies, the variation of the detection signal is small, and the detection signal proportional to the amount of the magnetic material can be obtained. Provided is a magnetic substance detection device that can be specified and that is stable against temperature changes.
【図１】本発明の一実施例に係る磁性体検出装置の構成
図。FIG. 1 is a configuration diagram of a magnetic body detection device according to an embodiment of the present invention.
【図２】コアの外形を示す斜視図。FIG. 2 is a perspective view showing the outer shape of a core.
【図３】検出部の信号処理回路を示すブロック図。FIG. 3 is a block diagram showing a signal processing circuit of a detection unit.
【図４】検出部の信号処理回路の他の実施例を示すブロ
ック図。FIG. 4 is a block diagram showing another embodiment of the signal processing circuit of the detection unit.
【図５】図１に示した検出部を複数個並べてなる磁性体
検出装置を示す側面図。5 is a side view showing a magnetic body detection device in which a plurality of detection units shown in FIG. 1 are arranged.
【図６】図５に示した磁性体検出装置の斜視図。FIG. 6 is a perspective view of the magnetic body detection device shown in FIG.
1 …検出部 2,5 …コア 3,4,6,7,100,200 …コイル 8 …紙葉類 9,10…支持具 13,19 …ブリッジ回路 14…発振回路 15,21,25…差動アンプ 16…位相同期検波回路 17…位相設定回路 18,26 …フィルタ回路 1… Detector 2,5… Core 3,4,6,7,100,200… Coil 8… Paper sheets 9,10… Supporting device 13,19… Bridge circuit 14… Oscillation circuit 15,21,25… Differential amplifier 16… Phase synchronous detection circuit 17 ... Phase setting circuit 18, 26 ... Filter circuit
Claims (7)
い開放端同志および短い開放端同志を所定間隙をもって
対向させてなる一対のコアと、 前記長い開放端同志を直列に接続してなる第１のコイル
と、 前記短い開放端同志を直列に接続してなる第２のコイル
と、 前記第１のコイルからの検出信号と前記第２のコイルか
らの検出信号とを処理する処理回路と、 を具備してなることを特徴とする磁性体検出装置。1. A pair of cores having two open ends having different lengths, the long open end and the short open end being opposed to each other with a predetermined gap, and the long open end being connected in series. A first coil, a second coil in which the short open ends are connected in series, and a process of processing a detection signal from the first coil and a detection signal from the second coil. A magnetic substance detection device comprising: a circuit.
されていることを特徴とする請求項１記載の磁性体検出
装置。2. The magnetic substance detection device according to claim 1, wherein the core is formed by laminating amorphous foils.
アの厚さの２倍以上に設定してなることを特徴とする請
求項１記載の磁性体検出装置。3. The magnetic substance detection device according to claim 1, wherein the distance w between the open ends of the core is set to be twice or more the thickness of the core.
記長い開放端同志の隙間Ｇの１／３以上に設定してなる
ことを特徴とする請求項１記載の磁性体検出装置。4. The magnetic material detection according to claim 1, wherein the difference P in length of the open ends of the core is set to be 1/3 or more of the gap G between the long open ends. apparatus.
い開放端同志の間隙Ｇの１／２以上に設定してなること
を特徴とする請求項１記載の磁性体検出装置。5. The magnetic substance detection device according to claim 1, wherein the gap d between the open ends of the core is set to be 1/2 or more of the gap G between the long open ends.
コアの開放端を結ぶ線が略平行となるように複数個並設
してなることを特徴とする磁性体検出装置。6. A magnetic substance detecting device according to claim 1, wherein a plurality of magnetic substance detecting devices are arranged side by side so that lines connecting the open ends of the respective cores are substantially parallel to each other.
同志の間隔Ｇ以上に設定してなることを特徴とする請求
項６記載の磁性体検出装置。7. The magnetic substance detecting device according to claim 6, wherein the distance s between the cores is set to be equal to or more than the distance G between the long open ends.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8045699A JPH09236642A (en) | 1996-03-04 | 1996-03-04 | Magnetic substance detecting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8045699A JPH09236642A (en) | 1996-03-04 | 1996-03-04 | Magnetic substance detecting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09236642A true JPH09236642A (en) | 1997-09-09 |
Family
ID=12726631
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8045699A Pending JPH09236642A (en) | 1996-03-04 | 1996-03-04 | Magnetic substance detecting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09236642A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7012424B2 (en) | 2004-02-27 | 2006-03-14 | Kabushiki Kaisha Toshiba | Magnetic material detecting apparatus |
| JP2006309339A (en) * | 2005-04-26 | 2006-11-09 | Toshiba Corp | Noncontact-type magnetic body sensing device |
| JP2014134448A (en) * | 2013-01-10 | 2014-07-24 | Kyushu Univ | Magnetic property measuring device, magnetic property measuring probe, and magnetic property measuring method |
| JP6940910B1 (en) * | 2021-07-01 | 2021-09-29 | 株式会社沖縄計測 | Magnetic Tomography System and Magnetic Tomography Method |
| JP6940911B1 (en) * | 2021-07-01 | 2021-09-29 | 株式会社沖縄計測 | Magnetic Tomography System and Magnetic Tomography Method |
-
1996
- 1996-03-04 JP JP8045699A patent/JPH09236642A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7012424B2 (en) | 2004-02-27 | 2006-03-14 | Kabushiki Kaisha Toshiba | Magnetic material detecting apparatus |
| JP2006309339A (en) * | 2005-04-26 | 2006-11-09 | Toshiba Corp | Noncontact-type magnetic body sensing device |
| JP2014134448A (en) * | 2013-01-10 | 2014-07-24 | Kyushu Univ | Magnetic property measuring device, magnetic property measuring probe, and magnetic property measuring method |
| JP6940910B1 (en) * | 2021-07-01 | 2021-09-29 | 株式会社沖縄計測 | Magnetic Tomography System and Magnetic Tomography Method |
| JP6940911B1 (en) * | 2021-07-01 | 2021-09-29 | 株式会社沖縄計測 | Magnetic Tomography System and Magnetic Tomography Method |
| JP2023007073A (en) * | 2021-07-01 | 2023-01-18 | 株式会社沖縄計測 | Magnetic survey system and magnetic survey method |
| JP2023007072A (en) * | 2021-07-01 | 2023-01-18 | 株式会社沖縄計測 | Magnetic survey system and magnetic survey method |
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