JPH0194258A - Diagnostic apparatus - Google Patents
Diagnostic apparatusInfo
- Publication number
- JPH0194258A JPH0194258A JP62253373A JP25337387A JPH0194258A JP H0194258 A JPH0194258 A JP H0194258A JP 62253373 A JP62253373 A JP 62253373A JP 25337387 A JP25337387 A JP 25337387A JP H0194258 A JPH0194258 A JP H0194258A
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric element
- calibration
- wave
- amplitude
- detecting
- 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
- 230000006866 deterioration Effects 0.000 claims abstract description 17
- 230000035945 sensitivity Effects 0.000 claims abstract description 15
- 238000001514 detection method Methods 0.000 claims description 30
- 238000003745 diagnosis Methods 0.000 abstract description 25
- 238000000034 method Methods 0.000 abstract 1
- 230000007423 decrease Effects 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000010356 wave oscillation Effects 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
この発明は、ＡＥセンサを使用して設備などの診断を行
なう診断装置に関する。なお、この明細書において、Ａ
Ｅという用語はアコースティックエミッション（Ａｃｏ
ｕｓｔｉｃ Ｅｍｉｓｓｉｏｎ）の略語として用いられ
る。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a diagnostic device that diagnoses equipment using an AE sensor. In addition, in this specification, A
The term E stands for acoustic emission (Aco
It is used as an abbreviation for ``ustic emission''.
従来技術とその問題点
ＡＥセンサは、物体から発生するＡＥ波を音響−電気変
換素子である圧電素子によって検出するものであり、Ａ
Ｅ波によって物体内の欠陥の有無がわかるため、設備診
断などに使用されている。Prior art and its problems AE sensors detect AE waves generated from an object using a piezoelectric element, which is an acoustic-electric conversion element.
E-waves can be used to detect defects in objects, so they are used for equipment diagnosis.
ところで、ＡＥセンサは使用により感度が劣化するため
、これを定期的に校正する必要があり、ＡＥセンサを用
いた診断装置では、従来、ＡＥセンサを設備から回収し
て校正している。Incidentally, since the sensitivity of the AE sensor deteriorates with use, it is necessary to periodically calibrate it. Conventionally, in a diagnostic apparatus using an AE sensor, the AE sensor is collected from the equipment and calibrated.
このため、ＡＥセンサの校正時には診断を長く中断しな
ければならず、たとえば発電機用軸受の診断などのよう
に診断を中断できないものについては問題がある。For this reason, when calibrating the AE sensor, the diagnosis must be interrupted for a long time, which poses a problem in cases where diagnosis cannot be interrupted, such as diagnosis of generator bearings.
この発明は、上記の問題を解決し、校正時にも診断を長
く中断する必要のない診断装置を提供することにある。The present invention solves the above problems and provides a diagnostic device that does not require long interruptions in diagnosis even during calibration.
問題点を解決するための手段
この発明による診断装置は、ＡＥ波検出用圧電素子の他
に校正時に模擬ＡＥ波を発振するための校正用圧電素子
が設けられたＡＥセンサと、校正時にＡＥセンサの校正
用圧電素子よりＡＥ波を発振し検出用圧電素子でそのＡ
Ｅ波を検出して検出用圧電素子の感度の劣化を検定する
手段とを備えているものである。Means for Solving the Problems A diagnostic device according to the present invention includes an AE sensor that is provided with a piezoelectric element for calibrating in addition to a piezoelectric element for detecting AE waves and a piezoelectric element for oscillating a simulated AE wave during calibration; The piezoelectric element for calibration oscillates an AE wave, and the piezoelectric element for detection detects the AE wave.
The apparatus is equipped with means for detecting E waves and verifying deterioration in sensitivity of the detection piezoelectric element.
作 用
校正時には、設備運転状態で、ＡＥセンサを設備に取付
けたまま、校正用圧電素子より所定の振幅の模擬ＡＥ波
を発振し、検出用圧電素子でその模擬ＡＥ波を検出して
、検出用圧電素子の感度の劣化を検定する。検出用圧電
素子の感度が劣化していれば、これにより検出した模擬
ＡＥ波の振幅が小さくなる。したがって、検出用圧電素
子で検出した模擬ＡＥ波の振幅により感度の劣化を判断
することができる。検出用圧電素子と校正用圧電素子は
同じ条件で使用されるため、大体同じように劣化する。During operational calibration, while the equipment is in operation, the piezoelectric element for calibration oscillates a simulated AE wave of a predetermined amplitude with the AE sensor attached to the equipment, and the piezoelectric element for detection detects the simulated AE wave. Verify the deterioration of the sensitivity of the piezoelectric element. If the sensitivity of the detection piezoelectric element is degraded, the amplitude of the detected simulated AE wave will become smaller. Therefore, deterioration in sensitivity can be determined based on the amplitude of the simulated AE wave detected by the detection piezoelectric element. Since the detection piezoelectric element and the calibration piezoelectric element are used under the same conditions, they deteriorate in roughly the same way.
これらが劣化すると、校正用圧電素子に同じ振幅の電気
信号を印加してもこれから発生する模擬ＡＥ波の振幅は
劣化の分だけ小さくなり、さらにこの模擬ＡＥ波を検出
した検出用圧電素子の出力の振幅も劣化の分だけ小さく
なる。このため、検出用圧電素子の劣化の度合をほぼ２
倍の感度でとらえることができる。When these deteriorate, even if an electrical signal of the same amplitude is applied to the calibration piezoelectric element, the amplitude of the simulated AE wave that will be generated will become smaller by the amount of deterioration, and the output of the detection piezoelectric element that detected this simulated AE wave will be reduced by the amount of deterioration. The amplitude also decreases by the amount of deterioration. Therefore, the degree of deterioration of the detection piezoelectric element can be reduced to approximately 2
It can be captured with twice the sensitivity.
実施例
以下１、図面を参照して、この発明を設備診断に用いら
れる診断装置に適用したいくつかの実施例を説明する。EMBODIMENTS In the following, some embodiments in which the present invention is applied to a diagnostic device used for equipment diagnosis will be described with reference to the drawings.
第１図は、第１実施例を示す。FIG. 1 shows a first embodiment.
設備診断装置はＡＥセンサ（１０）を備えており、ＡＥ
センサ（１０）のケース（１１）内には、設備診断のた
めにＡＥ波を検出するＡＥ波検出用圧電素子（１２）の
他に、校正時に模擬ＡＥ波を発振するための校正用圧電
素子（１３）が収容されている。The equipment diagnostic device is equipped with an AE sensor (10),
Inside the case (11) of the sensor (10), in addition to an AE wave detection piezoelectric element (12) that detects AE waves for equipment diagnosis, there is also a calibration piezoelectric element that oscillates a simulated AE wave during calibration. (13) is accommodated.
検出用圧電素子（１２）は、切換スイッチ（１４）を介
して診断部（１５）および校正部（１６）に接続されて
いる。校正用圧電素子（１３）は、ＡＥ波発振用の発振
器（１７）に接続されている。The detection piezoelectric element (12) is connected to a diagnostic section (15) and a calibration section (16) via a changeover switch (14). The calibration piezoelectric element (13) is connected to an oscillator (17) for AE wave oscillation.
設備運転中、通常、切換スイッチ（１４）は、第１図に
実線で示すように、診断部（１５）側に切換えられてお
り、診断部（１５）は検出用圧電素子（１２）で検出さ
れたＡＥ波により設備の診断を行なう。このとき、発振
器（１７）は作動しておらず、校正用圧電素子（１３）
から模擬ＡＥ波は発振されない。During equipment operation, the selector switch (14) is normally switched to the diagnostic section (15) side, as shown by the solid line in Fig. 1, and the diagnostic section (15) detects the detection using the piezoelectric element (12). The equipment is diagnosed using the generated AE waves. At this time, the oscillator (17) is not operating, and the piezoelectric element for calibration (13)
Therefore, no simulated AE wave is generated.
検出用圧電素子（１２）の校正を行なう場合、設備運転
状態で、ＡＥセンサ（１０）を設備に取付けたまま、切
換スイッチ（１４）を第１図に鎖線で示すように校正部
（１６）側に切換え、発振器（１７）を作動させて校正
用圧電素子（１３）から模擬ＡＥ波を発振する。なお、
発振器（１７）からは、模擬ＡＥ波の振幅が設備から発
生するＡＥ波の振幅より大きくなるような一定振幅の電
圧信号を校正用圧電素子（１３）に出力する。そして、
校正部（１６）は、検出用圧電素子（１２）で検出した
模擬ＡＥ波の振幅の大きさが所定の基準値より小さけれ
ば、検出用圧電素子（１２）の感度が劣化したと判断す
る。When calibrating the detection piezoelectric element (12), while the equipment is in operation, with the AE sensor (10) attached to the equipment, move the changeover switch (14) to the calibration part (16) as shown by the chain line in Figure 1. side, and activates the oscillator (17) to oscillate a simulated AE wave from the piezoelectric element for calibration (13). In addition,
The oscillator (17) outputs a voltage signal with a constant amplitude such that the amplitude of the simulated AE wave is larger than the amplitude of the AE wave generated from the equipment to the piezoelectric element for calibration (13). and,
The calibration unit (16) determines that the sensitivity of the detection piezoelectric element (12) has deteriorated if the magnitude of the amplitude of the simulated AE wave detected by the detection piezoelectric element (12) is smaller than a predetermined reference value.
検出用圧電素子（１２）の感度が劣化すれば、これによ
り検出した模擬ＡＥ波の振幅は小さくなる。したがって
、検出用圧電素子（１２）で検出した模擬ＡＥ波の振幅
により感度の劣化を判断することができる。検出用圧電
素子（１２）と校正用圧電素子（１３）は同一のケース
（１１）に収容されて同じ条件で使用されるため、検出
用圧電素子（１２）が劣化していれば、校正用圧電素子
（１３）も大体同じように劣化している。このため、発
振器（１７）から校正用圧電素子（１３）に同じ振幅の
電圧信号を印加してもこれから発生する模擬ＡＥ波の振
幅は劣化の分だけ小さくなり、さらにこの模擬ＡＥ波を
検出した検出用圧電素子（１２）の出力の振幅も劣化の
分だけ小さくなる。したがって、２つの圧電素子（１２
） （ｍの劣化の度合を合わせたほぼ２倍の感度で検出
用圧電素子（１２）の劣化の度合をとらえることができ
、精度が良い。If the sensitivity of the detection piezoelectric element (12) deteriorates, the amplitude of the detected simulated AE wave will become smaller. Therefore, deterioration in sensitivity can be determined based on the amplitude of the simulated AE wave detected by the detection piezoelectric element (12). The detection piezoelectric element (12) and the calibration piezoelectric element (13) are housed in the same case (11) and used under the same conditions, so if the detection piezoelectric element (12) has deteriorated, the calibration piezoelectric element (12) The piezoelectric element (13) has also deteriorated in roughly the same way. For this reason, even if a voltage signal of the same amplitude is applied from the oscillator (17) to the piezoelectric element for calibration (13), the amplitude of the simulated AE wave that will be generated will be smaller by the amount of deterioration, and furthermore, this simulated AE wave will be detected. The amplitude of the output of the detection piezoelectric element (12) also decreases by the amount of deterioration. Therefore, two piezoelectric elements (12
) (The degree of deterioration of the detection piezoelectric element (12) can be detected with a sensitivity that is approximately twice as high as the degree of deterioration of m, and the accuracy is good.
この診断装置の場合、設備運転状態で検出用圧電素子（
１２）の校正ができる。しかも、校正は、ＡＥセンサ（
１０）を設備に取付けたまま短時間でできるので、校正
時にも設備診断を長く中断する必要がない。In the case of this diagnostic device, the detection piezoelectric element (
12) can be calibrated. Moreover, the calibration is performed using the AE sensor (
10) can be done in a short time while it is attached to the equipment, so there is no need to interrupt equipment diagnosis for a long time during calibration.
第２図は第２実施例を示し、第１実施例と同じ部分には
同一の符号を付している。FIG. 2 shows a second embodiment, in which the same parts as in the first embodiment are given the same reference numerals.
第２実施例の場合、第１実施例の診断部（１５）と校正
部（１６）のかわりに、設備診断と定期的な校正を自動
的に行なう校正機能付診断部（ＩＢ）が設けられ、これ
に検出用圧電素子（１２）および発振器（１７）が接続
されている。In the case of the second embodiment, a diagnosis section with a calibration function (IB) that automatically performs equipment diagnosis and periodic calibration is provided in place of the diagnosis section (15) and calibration section (16) of the first embodiment. , to which a detection piezoelectric element (12) and an oscillator (17) are connected.
診断部（１８）は、通常、検出用圧電素子（１２）で検
出されたＡＥ波により設備診断を行い、定期的に、発振
器（１７）により校正用圧電素子（１３）から模擬ＡＥ
波を発振させて、第１実施例の場合と同様に校正を行な
う。The diagnosis section (18) normally performs equipment diagnosis using the AE waves detected by the detection piezoelectric element (12), and periodically generates simulated AE waves from the calibration piezoelectric element (13) using the oscillator (17).
A wave is oscillated and calibration is performed in the same manner as in the first embodiment.
第３図は第３実施例を示し、第１実施例と同じ部分には
同一の符号を付している。FIG. 3 shows a third embodiment, in which the same parts as in the first embodiment are given the same reference numerals.
第３実施例の場合、第１実施例の診断部（１５）と校正
部（１Ｂ）のかわりに、設備診断と校正に切換えられる
校正機能付診断部（１９）が設けられ、これに検出用圧
電素子（１２）が接続されている。In the case of the third embodiment, a diagnosis section (19) with a calibration function that can be switched to equipment diagnosis and calibration is provided in place of the diagnosis section (15) and calibration section (1B) of the first embodiment. A piezoelectric element (12) is connected.
また、校正用圧電素子（１３）が切換スイッチ（２０）
を介して診断部（１９）および発振器（１７）に接続さ
れている。In addition, the piezoelectric element for calibration (13) is connected to the changeover switch (20).
It is connected to the diagnostic section (19) and the oscillator (17) via.
通常は、切換スイッチ（２０）が第３図に実線で示すよ
うに診断部（１９）側に切換えられるとともに、診断部
（１９）が診断側に切換えられており、診断部（１９）
は２つの圧電素子（１２）（１３）の差動出力により設
備診断を行なう。Normally, the changeover switch (20) is switched to the diagnostic section (19) side as shown by the solid line in Fig. 3, and the diagnostic section (19) is also switched to the diagnostic side.
performs equipment diagnosis using differential outputs of two piezoelectric elements (12) and (13).
校正時には、切換スイッチ（２０）が第３図に鎖線で示
すように発振器（１７）側に切換えられるとともに、診
断部（１９）が校正側に切換えられ、診断部（１９）は
検出用圧電素子（１２）で検出された模擬ＡＥ波の振幅
により校正を行なう。During calibration, the changeover switch (20) is switched to the oscillator (17) side as shown by the chain line in Fig. 3, and the diagnostic section (19) is switched to the calibration side, and the diagnostic section (19) connects the piezoelectric element for detection. Calibration is performed using the amplitude of the simulated AE wave detected in (12).
第３実施例の診断装置のＡＥセンサ（１０）は、通常、
２つの圧電素子（１２）（１３）により差動型ＡＥセン
サとして動作し、ノイズを除去することができる。The AE sensor (10) of the diagnostic device of the third embodiment usually includes:
The two piezoelectric elements (12) and (13) operate as a differential AE sensor and can remove noise.
第４図は第４実施例を示し、第１実施例と同じ部分には
同一の符号を付している。FIG. 4 shows a fourth embodiment, in which the same parts as in the first embodiment are given the same reference numerals.
第４実施例の場合、第１実施例の診断部（１５）と校正
部（１６）のかわりに、設備診断と定期的な校正を自動
的に行なう校正機能付診断部（２１）が設けられ、これ
に検出用圧電素子（１２）、校正用圧電素子（１３）お
よび発振器（１７）がそれぞれ接続されている。In the case of the fourth embodiment, a diagnosis section with a calibration function (21) that automatically performs equipment diagnosis and periodic calibration is provided in place of the diagnosis section (15) and calibration section (16) of the first embodiment. , to which a detection piezoelectric element (12), a calibration piezoelectric element (13), and an oscillator (17) are respectively connected.
診断部（２１）は、通常、２つの圧電素子（１２）（１
３）の差動出力により設備診断を行ない、定期的に、発
振器（１７）により校正用圧電素子（１３）から模擬Ａ
Ｅ波を発振させて、第１実施例の場合と同様に校正を行
なう。The diagnostic section (21) usually includes two piezoelectric elements (12) (1
Equipment diagnosis is performed using the differential output of 3), and the oscillator (17) periodically generates a simulated A
E-wave is oscillated and calibration is performed in the same manner as in the first embodiment.
発明の効果
この発明の診断装置によれば、上述のように、設備運転
状態で、しかもこれを設備に取付けたまま、短時間で校
正ができ、校正時にも設備診断を長く中断する必要がな
い。また、検出用圧電素子の劣化の度合をほぼ２倍の高
感度でとらえることができ、通常は、検出用圧電素子の
他に校正用圧電素子も使用してＡＥセンサを差動型ＡＥ
センサとして動作させることもできる。Effects of the Invention According to the diagnostic device of the present invention, as described above, it is possible to perform calibration in a short time while the equipment is in operation and while it is attached to the equipment, and there is no need to interrupt equipment diagnosis for a long time during calibration. . In addition, it is possible to detect the degree of deterioration of the detection piezoelectric element with almost twice the sensitivity, and normally a calibration piezoelectric element is used in addition to the detection piezoelectric element to convert the AE sensor into a differential type AE sensor.
It can also be operated as a sensor.
第１図はこの発明の第１実施例を示す診断装置の構成図
、第２図はこの発明の第２実施例を示す第１図相当の図
面、第３図はこの発明の第３実施例を示す第１図相当の
図面、第４図はこの発明の第４実施例を示す第１図相当
の図面である。
（１０）・・・ＡＥセンサ、（１２）・・・ＡＥ波検出
用圧電素子の（１３）・・・校正用圧電素子、（１５）
・・・診断部、（１６）・・・校正部、（１７）・・・
発振器、（１ｇ） （１９） （２１）・・・校正機能
付診断部。
以 上
第４図Fig. 1 is a block diagram of a diagnostic device showing a first embodiment of the present invention, Fig. 2 is a drawing corresponding to Fig. 1 showing a second embodiment of the invention, and Fig. 3 is a third embodiment of the invention. FIG. 4 is a drawing corresponding to FIG. 1 showing a fourth embodiment of the present invention. (10)...AE sensor, (12)...piezoelectric element for AE wave detection, (13)...piezoelectric element for calibration, (15)
...Diagnosis section, (16)...Calibration section, (17)...
Oscillator, (1g) (19) (21)...Diagnostic section with calibration function. Above Figure 4
Claims (1)
するための校正用圧電素子が設けられたＡＥセンサと、
校正時にＡＥセンサの校正用圧電素子よりＡＥ波を発振
し検出用圧電素子でそのＡＥ波を検出して検出用圧電素
子の感度の劣化を検定する手段とを備えている診断装置
。an AE sensor provided with a piezoelectric element for calibration for oscillating a simulated AE wave during calibration in addition to the piezoelectric element for detecting the AE wave;
A diagnostic device comprising means for oscillating an AE wave from a piezoelectric element for calibration of an AE sensor during calibration, detecting the AE wave with a piezoelectric element for detection, and verifying deterioration in sensitivity of the piezoelectric element for detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62253373A JPH0194258A (en) | 1987-10-06 | 1987-10-06 | Diagnostic apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62253373A JPH0194258A (en) | 1987-10-06 | 1987-10-06 | Diagnostic apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0194258A true JPH0194258A (en) | 1989-04-12 |
Family
ID=17250454
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62253373A Pending JPH0194258A (en) | 1987-10-06 | 1987-10-06 | Diagnostic apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0194258A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006511802A (en) * | 2002-12-20 | 2006-04-06 | メディ−フィジックス・インコーポレイテッド | Calibration of polarization measuring station |
| WO2018081035A1 (en) * | 2016-10-25 | 2018-05-03 | Fisher Controls International Llc | Acoustic emission sensors with integral acoustic generators |
| WO2018118204A1 (en) * | 2016-12-21 | 2018-06-28 | Fisher Controls International Llc | Methods and apparatus to verify operation of acoustic emission sensors |
| US10161912B2 (en) | 2016-01-11 | 2018-12-25 | Fisher Controls International Llc | Methods and apparatus to test acoustic emission sensors |
| US10345273B2 (en) | 2016-01-11 | 2019-07-09 | Fisher Controls International Llc | Methods and apparatus to verify operation of acoustic emission sensors |
| CN110118829A (en) * | 2019-06-27 | 2019-08-13 | 中国工程物理研究院化工材料研究所 | A kind of test macro and method of the amplitude-frequency characteristic of acoustic emission sensor |
-
1987
- 1987-10-06 JP JP62253373A patent/JPH0194258A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006511802A (en) * | 2002-12-20 | 2006-04-06 | メディ−フィジックス・インコーポレイテッド | Calibration of polarization measuring station |
| US10161912B2 (en) | 2016-01-11 | 2018-12-25 | Fisher Controls International Llc | Methods and apparatus to test acoustic emission sensors |
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