JPH0213277B2 - - Google Patents
Info
- Publication number
- JPH0213277B2 JPH0213277B2 JP58153492A JP15349283A JPH0213277B2 JP H0213277 B2 JPH0213277 B2 JP H0213277B2 JP 58153492 A JP58153492 A JP 58153492A JP 15349283 A JP15349283 A JP 15349283A JP H0213277 B2 JPH0213277 B2 JP H0213277B2
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- signal
- reactance
- voltage comparator
- 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.)
- Expired - Lifetime
Links
- 238000001514 detection method Methods 0.000 claims description 17
- 239000000696 magnetic material Substances 0.000 claims description 7
- 239000000126 substance Substances 0.000 claims description 7
- 239000000843 powder Substances 0.000 description 20
- 239000012530 fluid Substances 0.000 description 7
- 239000003990 capacitor Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 230000010355 oscillation Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000005669 field effect Effects 0.000 description 2
- 230000007257 malfunction Effects 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 230000001052 transient effect Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V3/00—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
- G01V3/08—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices
- G01V3/081—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices the magnetic field is produced by the objects or geological structures
Landscapes
- Remote Sensing (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Geology (AREA)
- Environmental & Geological Engineering (AREA)
- Electromagnetism (AREA)
- General Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- Geophysics (AREA)
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
- Geophysics And Detection Of Objects (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明は粉体または流動体等に含まれる微少磁
性体の検知で粉体または流動体の近接有無を検知
することのできる微少磁性体検知装置に関するも
のである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a micromagnetic material detection device that can detect the presence or absence of a powder or fluid in the vicinity by detecting a micromagnetic material contained in the powder or fluid. It is something.
従来例の構成とその問題点
従来のリアクタンスを用いた発振式の磁性体検
知装置では、粉体または流動体中に含まれる微少
磁性体の検知により、粉体または流動体の近接有
無等の検知に使用することは非常に困難とされて
いた。すなわち、微少量の検知を行うために高感
度検知の必要があり、そのため各種の問題点が解
決されていないのが現状である。Configuration of conventional example and its problems In the conventional oscillation type magnetic material detection device using reactance, it is possible to detect the proximity of powder or fluid by detecting minute magnetic material contained in powder or fluid. It was said to be extremely difficult to use. That is, in order to detect minute amounts, high-sensitivity detection is required, and as a result, various problems remain unsolved.
たとえば、従来のリアクタンス変化を用いた発
振方式の磁性体検知装置では、被検知物中に設け
たリアクタンスで発振させた発振周波数と、基準
となる固定発振周波数との差の周波数検知構成で
微少磁性体検知を行なつていた。 For example, in a conventional magnetic material detection device that uses an oscillation method that uses reactance change, it detects minute magnetism by detecting the difference between the oscillation frequency oscillated by a reactance installed in the object to be detected and a fixed oscillation frequency that serves as a reference. It was performing body detection.
上記従来例では、回路構成が複雑となり、回路
コストが非常に高価であるため実用的でない。 In the conventional example described above, the circuit configuration is complicated and the circuit cost is very high, so it is not practical.
また、リアクタンスのインピーダンス変換方式
による磁性体検知装置があるが、この方式は微少
磁性体検知を行うために交流駆動と、連続的にア
ナログ検知を行つていることにより、Ｓ／Ｎ比が
悪く、誤動作し易く、ノイズに弱いなどの欠点を
有していた。 There is also a magnetic material detection device that uses a reactance impedance conversion method, but this method has a poor S/N ratio because it uses AC drive and continuous analog detection to detect minute magnetic materials. It had drawbacks such as being prone to malfunction and being sensitive to noise.
発明の目的
本発明は粉体または流動体等に含まれる微少磁
性体の有無の検知を、高精度に、しかもＳ／Ｎ比
が大きく、回路構成が簡単かつローコストで行え
る微少磁性体検知装置を提供することを目的とす
る。Purpose of the Invention The present invention provides a micromagnetic material detection device that can detect the presence or absence of micromagnetic materials contained in powders, fluids, etc. with high precision, a large S/N ratio, a simple circuit configuration, and low cost. The purpose is to provide.
発明の構成
本発明は上記目的を達成するためにリアクタン
ス素子に直流電圧を印加し、その時直流印加によ
るリアクタンスの過渡電流変化を、直流印加電圧
と同期させて検出保持するように構成したもので
ある。Structure of the Invention In order to achieve the above object, the present invention is configured to apply a DC voltage to a reactance element, and detect and hold a transient current change in the reactance due to the DC application in synchronization with the applied DC voltage. .
すなわち、本発明は、少なくとも磁気回路中の
一部に空間をもつリアクタンス素子と抵抗素子と
からなる２組の直列接続体と、この２組の直列接
続体それぞれに同時に直流電圧を印加する直流電
圧印加手段と、前記直列接続体それぞれのリアク
タンス素子と抵抗素子との接続点のそれぞれの二
電圧を比較する電圧比較器と、この電圧比較器の
出力信号を直流電圧印加手段の信号と同期させて
検出保持する手段とを有し、一方のリアクタンス
素子の磁気回中の空間に被検知物を包囲させて、
被検知物の微少磁性体の有無を検知するように構
成したものである。 That is, the present invention provides two series-connected bodies each consisting of a reactance element and a resistance element each having a space in at least a part of the magnetic circuit, and a DC voltage that simultaneously applies a DC voltage to each of the two series-connected bodies. an applying means, a voltage comparator for comparing two voltages at the connection points between the reactance element and the resistance element of each of the series connected bodies; and an output signal of the voltage comparator is synchronized with a signal of the DC voltage applying means. and detecting and holding means, and surrounding the object to be detected in the space of the magnetic circuit of one of the reactance elements,
It is configured to detect the presence or absence of a minute magnetic substance in an object to be detected.
実施例の説明
まず、少なくとも磁路中の１部に空間をもつリ
アクタンス素子の一例として、第１図Ａ，Ｂにそ
の構成図を示す。DESCRIPTION OF THE EMBODIMENTS First, as an example of a reactance element having a space in at least a part of the magnetic path, a configuration diagram thereof is shown in FIGS. 1A and 1B.
第１図の１はフエライトなどにより両端に鍔を
もつたＨ形の磁性体のコアーであり、このコアー
１にはコイル２が巻回され、このコイル２の両端
にはリード線３が接続され、かつコイル２の外周
には保護シール４が巻回されている。 1 in Fig. 1 is an H-shaped magnetic core with flanges at both ends made of ferrite, etc. A coil 2 is wound around this core 1, and lead wires 3 are connected to both ends of this coil 2. , and a protective seal 4 is wound around the outer periphery of the coil 2.
第２図は本発明の応用例を示すものである。 FIG. 2 shows an example of application of the present invention.
第２図は、粉体中に含まれる微少磁性体の検知
を行うことを利用した粉体のレベルチエツカーで
ある。 FIG. 2 shows a powder level checker that utilizes the detection of minute magnetic substances contained in powder.
５は粉体を収納する容器である。６は粉体であ
る。７は第１図で示したリアクタンス素子L1で
ある。８，９は粉体６のレベルを示す。１０はリ
アクタンス７L1の保持体である。 5 is a container for storing powder. 6 is powder. 7 is the reactance element L1 shown in FIG. 8 and 9 indicate the level of powder 6. 10 is a holder having a reactance of 7L1 .
第３図は本発明の微少磁性体検知装置の構成例
である。第３図の１１は電圧比較器であり、この
電圧比較器１１は、リアクタンス１２と抵抗素子
１３との直列接続体LR1およびリアクタンス素子
１４と抵抗素子１５との直列接続体LR2に直流電
圧印加を行うための手段である。１６は直列接続
体LR1およびLR2の接続点のおのおの二電圧Ｃ，
Ｅを比較するための電圧比較器である。Ｆは電圧
比較器１６の出力信号である。コンデンサ１７，
抵抗器１８，整流器１９，電圧比較器２０は直列
接続体LR1，LR2に直流電圧印加直後、同期検知
信号Ｇを得るための手段である。γe1，γe2は入
力信号Ａ電圧の約1/2に選ぶとよい。２１は電圧
比較器１６によつて得られた出力Ｆと、前記によ
つて得られた同期信号Ｇとで同期検知を行うため
の信号保持回路である。 FIG. 3 shows an example of the configuration of the minute magnetic substance detection device of the present invention. Reference numeral 11 in FIG. 3 is a voltage comparator, and this voltage comparator 11 supplies a DC voltage to a series connection body LR 1 of a reactance 12 and a resistance element 13 and a series connection body LR 2 of a reactance element 14 and a resistance element 15. This is a means for applying the voltage. 16 is the two voltages C at each connection point of the series connection bodies LR 1 and LR 2 ,
This is a voltage comparator for comparing E. F is the output signal of the voltage comparator 16. capacitor 17,
The resistor 18, the rectifier 19, and the voltage comparator 20 are means for obtaining the synchronization detection signal G immediately after applying a DC voltage to the series-connected bodies LR 1 and LR 2 . γe 1 and γe 2 are preferably selected to be approximately 1/2 of the input signal A voltage. 21 is a signal holding circuit for detecting synchronization between the output F obtained by the voltage comparator 16 and the synchronization signal G obtained above.
次に動作について説明する。各それぞれの動作
信号のタイムチヤートは第４図に示す通りであ
る。まず、第３図を参照し、直流印加電圧手段と
して別に設けてなる発振何の出力Ａにより、コン
デンサ１７および電圧比較器１１の入力に信号Ａ
を入力する。電圧比較器１１の出力にはＡ信号の
反転したＢ信号を得る。直列接続体LR1，LR2に
はＢ信号の波形で示される直流電圧が印加され
る。そして、第２図で示した粉体レベルチエツカ
ーに本発明を応用した場合、第３図のリアクタン
ス素子１２は、第２図のリアクタンス素子として
用いる。次に、粉体６のレベルが第２図の８の
時、直列接続体LR1，LR2の接続点の電圧はそれ
ぞれ電圧Ｃ，Ｅとなる。その時の第３図のリアク
タンス素子１２，抵抗素子１３，リアクタンス素
子１５の数値常数は、例えば13＝21KΩ，15＝
2.0KΩ，12＝1mH，14＝1mHである。 Next, the operation will be explained. The time chart of each operation signal is as shown in FIG. First, referring to FIG. 3, a signal A is applied to the input of the capacitor 17 and the voltage comparator 11 by the output A of an oscillating device separately provided as a DC applied voltage means.
Enter. The voltage comparator 11 outputs a B signal which is an inversion of the A signal. A DC voltage represented by the waveform of the B signal is applied to the series connected bodies LR 1 and LR 2 . When the present invention is applied to the powder level checker shown in FIG. 2, the reactance element 12 shown in FIG. 3 is used as the reactance element shown in FIG. Next, when the level of the powder 6 is 8 in FIG. 2, the voltages at the connection points of the series connected bodies LR 1 and LR 2 become voltages C and E, respectively. At that time, the numerical constants of reactance element 12, resistance element 13, and reactance element 15 in FIG. 3 are, for example, 13=21KΩ, 15=
2.0KΩ, 12=1mH, 14=1mH.
そして、電圧Ｃ，Ｅを電圧比較器１６で比較す
ることにより出力信号Ｆが得られる。 Then, by comparing the voltages C and E with a voltage comparator 16, an output signal F is obtained.
そして第３図のコンデンサ１７，抵抗器１８と
によつて形成される時定数回路と整流器１９と電
圧比較器２０とにより、入力信号Ａはパルス同期
信号Ｇとして電圧比較器２０の出力信号（第４図
参照）として得られる
今、粉体レベルは８であるので、リアクタンス
素子１２のリアクタンスは低くなり、電圧レベル
Ｅは電圧レベルＣより下がり、電圧比較器１６の
出力信号Ｆは下がり、信号保持回路２１は同期信
号Ｇで信号Ｆを保持し、出力信号Ｈは低レベルと
なる。 The time constant circuit formed by the capacitor 17 and resistor 18 shown in FIG. Since the powder level is now 8, the reactance of the reactance element 12 is low, the voltage level E is lower than the voltage level C, the output signal F of the voltage comparator 16 is lowered, and the signal is maintained. The circuit 21 holds the signal F with the synchronization signal G, and the output signal H becomes a low level.
次に第２図で示した粉体６のレベルが９の場
合、リアクタンス素子１２のリアクタンスが増加
し、電圧ベルＥは電圧レベルＣより上がり、電圧
比較器１６の検出信号Ｈは高レベルとなり、同期
信号Ｇにより信号保持回路２１の出力信号Ｈは高
レベル信号となる。この時の信号Ａ，Ｂ，Ｃ，
Ｅ，Ｆ，Ｇ，Ｈを、第４図のタイミングチヤート
で示す。 Next, when the level of the powder 6 shown in FIG. 2 is 9, the reactance of the reactance element 12 increases, the voltage level E rises above the voltage level C, and the detection signal H of the voltage comparator 16 becomes high level. The synchronization signal G causes the output signal H of the signal holding circuit 21 to become a high level signal. At this time, the signals A, B, C,
E, F, G, and H are shown in the timing chart of FIG.
すなわち、第２図で示した粉体６のレベルが、
リアクタンス素子７を基準に高いか低いかのレベ
ルを判定することができるのである。 That is, the level of the powder 6 shown in FIG.
It is possible to determine whether the level is high or low based on the reactance element 7.
このように本発明は、粉体または流動体等の微
少磁性体の検知で、残量検知等の応用ができるも
のである。 As described above, the present invention can be applied to detection of a minute magnetic material such as a powder or a fluid, and to detect the remaining amount.
上述の本発明の実施例は一例であつて、限定さ
れないことは勿論である。例えば、信号保持手段
において、第５図の実施例でも同様の効果を示
す。第５図は、電界効果トランジスタ２２とコン
デンサ２３とにより、比較検出信号Ｆを同期信号
Ｇで同期させて信号保持させることができる。ま
た、上記実施例は粉体を用いたが流動体でも同様
の効果が得られる。 It goes without saying that the embodiments of the present invention described above are merely examples, and are not limited thereto. For example, in the signal holding means, the embodiment shown in FIG. 5 exhibits similar effects. In FIG. 5, a comparison detection signal F can be synchronized with a synchronization signal G and held by a field effect transistor 22 and a capacitor 23. Further, although powder was used in the above embodiment, the same effect can be obtained using a fluid.
発明の効果
以上のように本発明によれば、２組からなるリ
アクタンス素子と抵抗素子との過渡電流変化によ
るおのおのの接続点の電位比較および印加電圧と
の同期検出保持により、従来と比較してＳ／Ｎ比
が非常に優れ、誤動作がないとともに、外来イノ
ズに対して強く、しかも高感度であり、ローコス
ト化等が実現できるものである。また、本発明は
構成が非常に簡単であり、温度変化に対して、２
組の直列接続体で温度補償ができ、非常に安定性
に優れた微少磁性体の検知ができる。Effects of the Invention As described above, according to the present invention, by comparing the potential at each connection point due to transient current changes between two sets of reactance elements and resistance elements, and by detecting and maintaining synchronization with the applied voltage, compared to the conventional method, It has an extremely excellent S/N ratio, does not malfunction, is resistant to foreign noise, has high sensitivity, and can be realized at low cost. In addition, the present invention has a very simple structure, and is resistant to temperature changes.
Temperature compensation can be performed by connecting a pair of devices in series, and minute magnetic substances can be detected with extremely high stability.
本発明は以上のように種々の利点をもち、産業
的価大なるものである。 As described above, the present invention has various advantages and is of great industrial value.
第１図Ａ，Ｂは本発明の微少磁性体検知装置に
用いるリアクタンス素子の一実施例の上面図と正
面図、第２図は同リアクタンス素子の応用例を示
す概略構成図、第３図は本発明の微少磁性体検知
装置の一実施例を示す電気的回路図、第４図は各
部の電圧波形による動作タイムチヤート、第５図
は信号保持手段の一実施例を示す電気的回路図で
ある。
１……コアー、２……コイル、３……リード
線、４……保護シール、５……粉体収納容器、６
……粉体、７……リアクタンス素子、８，９……
粉体のレベル、１０……保持体、１１……電圧比
較器、１２……リアクタンス素子、１３……抵抗
素子、１４……リアクタンス素子、１５……抵抗
素子、１６……電圧比較器、１７……コンデン
サ、１８……抵抗器、１９……整流器、２０……
電圧比較器、２１……信号保持回路、２２……電
界効果トランジスタ、２３……コンデンサ。
1A and 1B are top and front views of an embodiment of a reactance element used in the minute magnetic substance detection device of the present invention, FIG. 2 is a schematic configuration diagram showing an application example of the reactance element, and FIG. 3 is a FIG. 4 is an electrical circuit diagram showing an embodiment of the minute magnetic substance detection device of the present invention, FIG. 4 is an operation time chart based on voltage waveforms of each part, and FIG. 5 is an electrical circuit diagram showing an embodiment of the signal holding means. be. 1... Core, 2... Coil, 3... Lead wire, 4... Protective seal, 5... Powder storage container, 6
...Powder, 7...Reactance element, 8,9...
Powder level, 10... Holder, 11... Voltage comparator, 12... Reactance element, 13... Resistance element, 14... Reactance element, 15... Resistance element, 16... Voltage comparator, 17 ... Capacitor, 18 ... Resistor, 19 ... Rectifier, 20 ...
Voltage comparator, 21... signal holding circuit, 22... field effect transistor, 23... capacitor.
Claims (1)
アクタンス素子と抵抗素子とからなる２組の直列
接続体と、この２組の直列接続体それぞれに同時
に直流電圧を印加する直流電圧印加手段と、前記
直列接続体それぞれのリアクタンス素子と抵抗素
子との接続点のそれぞれの二電圧を比較する電圧
比較器と、この電圧比較器の出力信号を前記直流
電圧印加手段の信号と同期させて検出保持する手
段とを有し、前記電圧比較器により検出した信号
を検出保持させ、かつ一方のリアクタンス素子の
磁気回路中の空間に被検知物を包囲させ、被検知
物の微少磁性体の有無を検知するように構成した
ことを特徴とする微少磁性体検知装置。1. Two sets of series connected bodies each consisting of a reactance element and a resistance element having a space in at least a part of the magnetic circuit, a DC voltage applying means for simultaneously applying a DC voltage to each of the two sets of series connected bodies, and the above-mentioned A voltage comparator that compares two voltages at the connection points between the reactance element and the resistance element of each series connection body, and means for detecting and holding the output signal of the voltage comparator in synchronization with the signal of the DC voltage applying means. and detects and holds the signal detected by the voltage comparator, surrounds the object to be detected in the space in the magnetic circuit of one of the reactance elements, and detects the presence or absence of minute magnetic material in the object to be detected. A minute magnetic substance detection device characterized by having the following configuration.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58153492A JPS6044883A (en) | 1983-08-22 | 1983-08-22 | Apparatus for detecting minute magnetic body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58153492A JPS6044883A (en) | 1983-08-22 | 1983-08-22 | Apparatus for detecting minute magnetic body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6044883A JPS6044883A (en) | 1985-03-11 |
| JPH0213277B2 true JPH0213277B2 (en) | 1990-04-03 |
Family
ID=15563742
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58153492A Granted JPS6044883A (en) | 1983-08-22 | 1983-08-22 | Apparatus for detecting minute magnetic body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6044883A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5959737U (en) * | 1982-10-12 | 1984-04-19 | タキロン株式会社 | Green onion cultivation equipment |
| JPH0724502B2 (en) * | 1989-04-25 | 1995-03-22 | 鐘淵化学工業株式会社 | Cultivation method of soft white onion |
| JPH06289146A (en) * | 1992-02-17 | 1994-10-18 | Tatsuo Miyagawa | Foreign matter detecting device |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5313942A (en) * | 1976-07-23 | 1978-02-08 | Nippon Signal Co Ltd:The | Magnetic detector |
| JPS57179682A (en) * | 1981-04-30 | 1982-11-05 | Toshiba Corp | Metal detector |
-
1983
- 1983-08-22 JP JP58153492A patent/JPS6044883A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5313942A (en) * | 1976-07-23 | 1978-02-08 | Nippon Signal Co Ltd:The | Magnetic detector |
| JPS57179682A (en) * | 1981-04-30 | 1982-11-05 | Toshiba Corp | Metal detector |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6044883A (en) | 1985-03-11 |
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