JPS5920100B2 - Electromagnetic induction flaw detection method - Google Patents
Electromagnetic induction flaw detection methodInfo
- Publication number
- JPS5920100B2 JPS5920100B2 JP3439979A JP3439979A JPS5920100B2 JP S5920100 B2 JPS5920100 B2 JP S5920100B2 JP 3439979 A JP3439979 A JP 3439979A JP 3439979 A JP3439979 A JP 3439979A JP S5920100 B2 JPS5920100 B2 JP S5920100B2
- Authority
- JP
- Japan
- Prior art keywords
- flaw
- signal
- electromagnetic induction
- flaw detection
- detection method
- 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
Links
Landscapes
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Description
【発明の詳細な説明】
本発明は金属線材などの傷を電磁誘導により探知する方
法に関し、傷の有無を正しく検知するようにしたもので
ある。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting flaws in metal wires or the like by electromagnetic induction, and is designed to accurately detect the presence or absence of flaws.
電磁誘導による探傷方法は、従来より知られている。Flaw detection methods using electromagnetic induction have been known for a long time.
これは、発振器１から所定周波数の信号を発生させ、走
行する金属線材などの試料２に傷があると平衡装置３の
サーチコイル４に信号が誘起され、これにより平衡装置
３のバランスがくずれて同装置３の出力に所定の信号が
発生するようにし、この信号を増幅器５で増幅し、ＡＭ
ｊｉ＄Ｑ波器６で検波し、更にそれを増幅器Ｔで増幅し
て記録計８に記録するようにしたものである。This is done by generating a signal at a predetermined frequency from an oscillator 1, and when there is a scratch on a running sample 2 such as a metal wire, a signal is induced in the search coil 4 of the balance device 3, which causes the balance device 3 to become unbalanced. A predetermined signal is generated at the output of the device 3, and this signal is amplified by the amplifier 5.
The signal is detected by a Q wave detector 6, amplified by an amplifier T, and recorded by a recorder 8.
ところで、従来は操業のスタート前に、傷擬似信号発生
器９からレベル設定器１０で設定された所定レベルの傷
擬似信号を発生させ、これを分圧してサーチコイル４に
加えながらゲイン調整器１１を調整して、増幅器１の出
力信号のレベルが予め定めた一定値と同じになるように
している。By the way, conventionally, before the start of operation, a flaw simulating signal of a predetermined level set by a level setter 10 is generated from a flaw simulating signal generator 9, and while the voltage is divided and applied to the search coil 4, the flaw simulating signal is generated by a gain adjuster 11. is adjusted so that the level of the output signal of the amplifier 1 is the same as a predetermined constant value.
しかし、一旦調整して操業を開始すると、あとは操業が
終るまで再調整しないため、雰囲気温度、それに湿度、
時間の経過などにより探傷装置の特性などが変化し、増
幅器Ｔの出力が、サーチコイル４に入つた傷信号に正確
に対応しなくなることがある。これでは高精度の探傷を
行ない得ないという欠点があつた。本発明は、このよう
な欠点を解消するため、操業を開始してからでも、探傷
装置を適時自動調整し得るようにしたものである。However, once the adjustment is made and operation begins, it is not readjusted until the operation is finished, so the atmospheric temperature, humidity, etc.
As the characteristics of the flaw detection device change over time, the output of the amplifier T may no longer accurately correspond to the flaw signal input to the search coil 4. This method had the disadvantage that high-precision flaw detection could not be performed. In order to eliminate such drawbacks, the present invention is capable of automatically adjusting the flaw detection device in a timely manner even after the start of operation.
以下本発明の一例を図面に基づき詳記する。An example of the present invention will be described in detail below based on the drawings.
試料２を走行させ、その傷に基づく信号変化を平衡装置
３のサーチコイル４で検出し、これを増幅器５、ＡＭ検
波器６、増幅器７の測定系により検出するのは従来と同
じである。本発明では、傷擬似信号発生器９からの傷擬
似信号を平衡装置３から測定系に入れると共に差動増幅
器１２にも人れ、一方同増幅器１２には増幅器Ｔの出力
信号をも人れて、差動増幅器１２から、両信号の差に応
じた正・負電圧による差信号を取出す。The sample 2 is run, and the search coil 4 of the balance device 3 detects a signal change due to the scratch, and this is detected by the measurement system of the amplifier 5, AM detector 6, and amplifier 7, as in the conventional case. In the present invention, the flaw simulating signal from the flaw simulating signal generator 9 is input to the measurement system from the balance device 3 and also to the differential amplifier 12, while the output signal of the amplifier T is also input to the differential amplifier 12. , a differential signal is extracted from the differential amplifier 12 based on positive and negative voltages corresponding to the difference between the two signals.
この差信号をサーボアンプ１３により増幅し、その出力
によりサーボモータ等の駆動体１４を前記正・負電圧に
対応させて正・逆回転させ、ゲイン調整器１１を差動増
幅器１２の出力が零になるよう自動的に調整するように
したものである。従つて、本発明では、増幅器７からの
出力信号が傷擬似信号発生器９から出力される信号レベ
ルと常に同一となるよう増幅レベルが調整されるため、
操業中の雰囲気温度や湿度、時間経過などによる探傷装
置の特性変化が補正され、特性変化Ｖこ伴なう誤差が生
じない。なお、傷擬似信号及び増幅器７の出力信号を差
動増幅器１２に入れるには、連動スイツチ１５，１６，
１７を手動或は自動的にオンする。This difference signal is amplified by the servo amplifier 13, and its output causes the driver 14, such as a servo motor, to rotate in positive and reverse directions in accordance with the positive and negative voltages, and the gain adjuster 11 is adjusted so that the output of the differential amplifier 12 is zero. It is automatically adjusted so that Therefore, in the present invention, since the amplification level is adjusted so that the output signal from the amplifier 7 is always the same as the signal level output from the flaw simulating signal generator 9,
Changes in the characteristics of the flaw detection device due to atmospheric temperature and humidity during operation, the passage of time, etc. are corrected, and errors associated with changes in characteristics do not occur. Incidentally, in order to input the flaw simulating signal and the output signal of the amplifier 7 to the differential amplifier 12, interlocking switches 15, 16,
17 manually or automatically.
本発明は叙上のように、スイツチ１５，１６，１７をオ
ンするだけで、温・湿度や経時変化などによる探傷装置
の特性変化を自動的に補正できるため操業中であつても
調整できる。As described above, in the present invention, by simply turning on the switches 15, 16, and 17, changes in characteristics of the flaw detection apparatus due to temperature, humidity, changes over time, etc. can be automatically corrected, so adjustments can be made even during operation.
従つて、増幅器７の出力信号は、平衡装置３に入る傷信
号に正確に対応することになり、高精度の探傷を行うこ
とができる。Therefore, the output signal of the amplifier 7 accurately corresponds to the flaw signal entering the balance device 3, and highly accurate flaw detection can be performed.
図は本発明の一実施例を示すプロツク図である。
１は発振器、２は試料、３は平衡装置、４はサーチコイ
ル、５は増幅器、６はＡＭ検波器、７は増幅器、９は傷
擬似信号発生器。The figure is a block diagram showing one embodiment of the present invention. 1 is an oscillator, 2 is a sample, 3 is a balance device, 4 is a search coil, 5 is an amplifier, 6 is an AM detector, 7 is an amplifier, and 9 is a flaw simulating signal generator.
Claims (1)
より検出し、この信号を検波して傷の有無を検出するよ
うにした電磁誘導探傷方法において、傷擬似信号発生器
からの適宜レベルの傷擬似信号を平衡装置から測定系に
入れ、測定系から出力される傷擬似信号と傷擬似信号発
生器からの傷擬似信号とを比較し、その差出力により駆
動体を動作させて両信号の差が０になるよう測定系の検
波出力信号を自動調整するようにした電磁誘導探傷方法
。1 In an electromagnetic induction flaw detection method in which a signal induced when a sample has a flaw is detected by a balance device, and this signal is detected to detect the presence or absence of flaws, an appropriate level of signal from a flaw simulating signal generator is detected. The flaw simulating signal is input from the balance device into the measurement system, the flaw simulating signal output from the measuring system is compared with the flaw simulating signal from the flaw simulating signal generator, and the difference output is used to operate the driver to detect both signals. An electromagnetic induction flaw detection method that automatically adjusts the detection output signal of the measurement system so that the difference is zero.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3439979A JPS5920100B2 (en) | 1979-03-26 | 1979-03-26 | Electromagnetic induction flaw detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3439979A JPS5920100B2 (en) | 1979-03-26 | 1979-03-26 | Electromagnetic induction flaw detection method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS55126854A JPS55126854A (en) | 1980-10-01 |
| JPS5920100B2 true JPS5920100B2 (en) | 1984-05-10 |
Family
ID=12413098
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3439979A Expired JPS5920100B2 (en) | 1979-03-26 | 1979-03-26 | Electromagnetic induction flaw detection method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5920100B2 (en) |
-
1979
- 1979-03-26 JP JP3439979A patent/JPS5920100B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55126854A (en) | 1980-10-01 |
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