JPH10176970A - Detecting device for leak place - Google Patents

Detecting device for leak place

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Publication number
JPH10176970A
JPH10176970A JP35260996A JP35260996A JPH10176970A JP H10176970 A JPH10176970 A JP H10176970A JP 35260996 A JP35260996 A JP 35260996A JP 35260996 A JP35260996 A JP 35260996A JP H10176970 A JPH10176970 A JP H10176970A
Authority
JP
Japan
Prior art keywords
sound
leak
sound wave
point
correlation function
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
Application number
JP35260996A
Other languages
Japanese (ja)
Inventor
Shigeru Makino
繁 牧野
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
RES KK
Original Assignee
RES KK
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by RES KK filed Critical RES KK
Priority to JP35260996A priority Critical patent/JPH10176970A/en
Publication of JPH10176970A publication Critical patent/JPH10176970A/en
Pending legal-status Critical Current

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Abstract

PROBLEM TO BE SOLVED: To provide a device which can be used easily by everybody and by which the leak place of a fluid can be inspected and detected surely. SOLUTION: A leak-place detecting device is constituted as a movable probe 10 which supports two or more sound-wave detectors by keeping a constant distance. Output signals from the sound-wave detectors 11a, 11b are passed through an adaptive filter, they are converted into digital signals by an A/D converter, a cross-correlation function is numerically calculated by a DSP on the basis of the digital signals, and the direction of a leak point is judged so as to be displayed on an LED display 14. The cross-correlation function is computed by an FFT method, the Blackman-Chewkey method or the like. When the sound-wave detectors are brought into contact with a pipe or a can body having a leak, an LED display device in a direction close to a leak point is turned on, and the probe is moved to the direction. When an LED device in the center is turned on, it indicates that a leak point exists between the sound- wave detectors.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、気体、液体等の流
体配管もしくは缶体の検査に用いる、漏洩箇所検査、発
見装置に関する。配管もしくは缶体は、露出しているも
の、地中等に埋設されたものいずれでも良い。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting and finding leaking points used for inspecting fluid pipes or can bodies of gas, liquid, or the like. The pipe or the can body may be exposed or buried underground.

【0002】[0002]

【従来の技術】従来、配管の漏洩箇所を検査し発見する
ためには、主として、石鹸水を刷毛で塗布して泡の発生
を見る方法、水中において、空気等の気体を圧力をかけ
て注入し、泡の発生を見る方法が行なわれてきた。しか
し、このような方法は非常に手間がかかる上、熟練が必
要で、機械化は容易ではない。
2. Description of the Related Art Conventionally, in order to inspect and find a leak point in a pipe, a method of applying soap water with a brush to see the generation of bubbles, and injecting a gas such as air into water under pressure. Then, a method of observing the generation of bubbles has been used. However, such a method is very labor-intensive, requires skill, and is not easy to mechanize.

【0003】漏洩音を捕える方法も存在するが(例え
ば、特開昭66−66128号、特開平1−59028
号など)、この方法は一般に漏洩の有無を検知するのみ
であり、漏洩箇所を調べることはできない。一方、漏洩
箇所を双曲線の漸近線の交点として推定する方法が、特
開昭59−5951号に記載されているが、音波の到達
時間差を測定する方法が不明確であり、交点を求めるに
も作図等の手作業を要するもので、実施化が困難であ
る。さらに、特開昭62−297741号には相互相関
関数を用いる方法が提案されているが、適用出来るのは
細管での固定式検出に限られ、従来法を置き換えるには
至っていない。
There are methods for capturing leaked sound (for example, see JP-A-66-66128 and JP-A-1-59028).
This method generally only detects the presence or absence of a leak, and cannot check the location of the leak. On the other hand, a method of estimating a leak point as an intersection of an asymptote of a hyperbola is described in JP-A-59-5951, but the method of measuring the difference in arrival time of sound waves is unclear, and it is also necessary to find the intersection. It requires manual work such as drawing and is difficult to implement. Further, Japanese Patent Application Laid-Open No. Sho 62-297741 proposes a method using a cross-correlation function, but applicable only to fixed detection using a thin tube, and has not yet replaced the conventional method.

【0004】[0004]

【発明が解決しようとする課題】従って、本発明は、前
記したような従来技術の問題点を解決し、だれでも容易
に使用でき、かつ確実に流体の漏洩箇所を検査、発見し
うる装置を提供することを課題とする。
SUMMARY OF THE INVENTION Accordingly, the present invention solves the above-mentioned problems of the prior art, and provides an apparatus which can be easily used by anyone and which can surely inspect and find a leaking portion of a fluid. The task is to provide.

【0005】[0005]

【課題を解決するための手段】上記課題を解決するた
め、本発明によれば、2個以上の音波検出器を一定距離
を保って支持する可動式プローブとして構成され、漏洩
箇所から伝播する漏洩音を検出する音波検出器と、該音
波検出器の出力を、同時もしくは既知の時間差をもって
ADコンバータでサンプリングし、その相互相関関数を
数値計算することによって、配管もしくは缶体の漏洩点
の方向を判定し、表示する手段とを有することを特徴と
する漏洩箇所検出装置が提供される。
According to the present invention, there is provided a movable probe which supports two or more sound wave detectors at a predetermined distance, and transmits a leak from a leak location. A sound wave detector that detects sound and the output of the sound wave detector are sampled simultaneously or with a known time difference by an AD converter, and the cross-correlation function is numerically calculated to determine the direction of the leak point of the pipe or can body. And a means for determining and displaying the information.

【0006】さらに本発明によれば、3個以上の音波検
出器を相互に一定距離を保って支持する可動式プローブ
として構成され、漏洩箇所から伝播する漏洩音を検出す
る音波検出器と、該音波検出器の出力を、同時もしくは
既知の時間差をもってADコンバータでサンプリング
し、その相互相関関数を数値計算することによって、各
検出器から漏洩点までの距離差を算出し、配管もしくは
缶体の漏洩点の方向及び位置を、該音波検出器位置を焦
点とする双曲線の交点として判定し、表示する手段とを
有することを特徴とする漏洩箇所検出装置が提供され
る。
According to the present invention, there is further provided a sound probe configured as a movable probe for supporting three or more sound wave detectors at a certain distance from each other, and detecting a sound leaking from a leak location. The output of the sound wave detector is sampled by an AD converter at the same time or with a known time difference, and the cross-correlation function is numerically calculated to calculate the difference in the distance from each detector to the leak point. Means for determining and displaying the direction and position of a point as an intersection of a hyperbola having the position of the sound wave detector as a focal point, and displaying the leaked point.

【0007】また、好適な態様においては、上記に加え
て、相互相関関数を検出する前処理として、あらかじめ
各検出器の出力信号に対して適用するために、最大エン
トロピー法の予測誤差フィルタを用いた適応フィルタを
さらに設け、精度を向上する。ここで用いる音波検出器
は、加速度センサ、マイクロホン等を使用し、露出した
配管もしくは缶体については、直接接触させる。地中等
に埋設された配管もしくは缶体については、地表に音波
検出器を接触させる。さらに、本発明の好適な態様で
は、音波検出器を音波発信器として兼用し、音波検出器
の互いの相対的距離を校正する。
In a preferred embodiment, in addition to the above, a prediction error filter of a maximum entropy method is used as a pre-process for detecting a cross-correlation function in order to apply the cross-correlation function to an output signal of each detector in advance. The added adaptive filter is further provided to improve the accuracy. As the sound wave detector used here, an acceleration sensor, a microphone, or the like is used, and the exposed pipe or can body is brought into direct contact. For pipes or cans buried underground or the like, an acoustic wave detector is brought into contact with the surface of the ground. Further, in a preferred aspect of the present invention, the sound wave detector is also used as a sound wave transmitter, and the relative distance between the sound wave detectors is calibrated.

【0008】[0008]

【発明の実施の形態と作用】配管端を密閉し、空気又は
水等の流体を圧入した時、配管に漏洩箇所があれば、そ
の位置より流体が漏れ、漏洩音を発生する。今、図1の
ように漏洩点、検出点x、検出点yが位置しているとす
る。金属中の音速は約5km/sなので、検出点yで
は、検出点xに比べて約10μs遅れてほぼ同様の音波
を検出するはずである。
DESCRIPTION OF THE PREFERRED EMBODIMENTS When the end of a pipe is sealed and a fluid such as air or water is press-fitted, if there is a leak in the pipe, the fluid leaks from that location, generating a leak sound. Now, it is assumed that the leak point, the detection point x, and the detection point y are located as shown in FIG. Since the speed of sound in metal is about 5 km / s, almost the same sound wave should be detected at the detection point y about 10 μs later than the detection point x.

【0009】相互相関関数は、下記式(1)で定義され
ている。
The cross-correlation function is defined by the following equation (1).

【数1】 ここで、上線は時間的平均を表わしている。これは、ラ
グτずらして変量x(t)とy(t)を見た場合、どの
程度相似形になっているかを示す尺度と考えることが出
来る。検出点x、検出点yで検出した音波について計算
すれば、当然ラグτ=10μsにピークを持つ曲線とな
る。この様子を図2に示す。
(Equation 1) Here, the upper line represents the temporal average. This can be considered as a scale indicating how similar the variables x (t) and y (t) are when viewed with the lag τ shifted. If calculation is performed on the sound waves detected at the detection points x and y, a curve having a peak at lag τ = 10 μs is obtained. This is shown in FIG.

【0010】一方、自己相関関数は、下記式(2)で定
義されている。
On the other hand, the autocorrelation function is defined by the following equation (2).

【数2】 これは、ラグτずらして変量x(t)をそれ自身に重ね
たとき、どの程度相似形になっているか、言い換えれば
ラグτの周期性を持っているかどうかを示す尺度と考え
ることが出来る。
(Equation 2) This can be considered as a measure indicating how similar the variable x (t) is when the variable x (t) is overlapped with itself by shifting the lag τ, in other words, whether or not the lag τ has periodicity.

【0011】もし、漏洩音に周期性があれば、前述の相
互相関関数はτ=10μs以外にも、その周期Tに対し
τ=(10+T)μsのピークを生じるが、通常、漏洩
音に周期性はなく、その自己相関関数はラグτ=0の近
傍以外に大きな値を持たない。このような信号は白色雑
音と呼ばれる。よって、検出点x,yの相互相関関数に
生じるピークは、それぞれの検出点から漏洩点までの距
離差により、音波の到達時間差を生じた結果を反映する
と考えることが出来る。このことから逆に、漏洩音の有
無より、漏洩自体の有無を判定し、同時に各検出点の相
互相関関数のピークにより、漏洩点までの距離差及び方
向を判定する事ができる。
If the leaked sound has periodicity, the above cross-correlation function produces a peak of τ = (10 + T) μs with respect to the period T in addition to τ = 10 μs. The autocorrelation function does not have a large value except in the vicinity of the lag τ = 0. Such a signal is called white noise. Therefore, it can be considered that the peak generated in the cross-correlation function of the detection points x and y reflects the result of the difference in the arrival time of the sound wave due to the distance difference from each detection point to the leak point. Conversely, the presence or absence of the leak itself can be determined from the presence or absence of the leak sound, and at the same time, the distance difference and the direction to the leak point can be determined by the peak of the cross-correlation function of each detection point.

【0012】検出点が2点の場合、配管表面を展開し平
面とみなした状態では、その2点への距離差が等しくな
る双曲線上のどこかに漏洩点がある事がわかる。これを
検出点を結ぶ線分の垂直二等分線を境界線として、どち
らの検出点側にあるか、或いは、その垂直二等分線の近
辺にあるか判定し表示するのは、数学的にきわめて容易
である。
When the number of detection points is two, it can be seen that there is a leak point somewhere on the hyperbola where the distance difference between the two points is equal when the pipe surface is expanded and regarded as a plane. Using the vertical bisector of the line connecting the detection points as a boundary line, it is mathematically necessary to determine which detection point is closer to or near the vertical bisector, and display it. It is very easy.

【0013】検出点が3点以上ある場合、2点で考えた
時の双曲線が3以上になる。漏洩点は、それぞれの検出
点間から求めた双曲線が同時に交差する点と特定される
ので、高精度に位置を判定できる。図3に、この様子を
図示する。実際は、双曲線を方程式として表し、2つの
双曲線毎に組にして、連立方程式を解くことになるが、
その手法は極く一般に知られたもので、CPU等を用い
れば簡単に数値解を得られる。こうして得られた平面座
標を、表示器に表示する。
When there are three or more detection points, the hyperbola when considering two points is three or more. Since the leak point is specified as a point where the hyperbolas obtained from the respective detection points simultaneously intersect, the position can be determined with high accuracy. FIG. 3 illustrates this state. Actually, the hyperbola is represented as an equation, and a set of two hyperbolas is set to solve the simultaneous equations.
The method is very generally known, and a numerical solution can be easily obtained by using a CPU or the like. The plane coordinates thus obtained are displayed on a display.

【0014】次に、漏洩点が、同時に複数存在する場合
について説明する。別の漏洩点から発生した漏洩音は、
互いに独立の白色雑音であり、それぞれの漏洩音を単独
に捉え、これを基に計算した相互相関関数は、どこにも
大きな値を持たない。すなわち、各検出点の相互相関関
数に生じる複数のピークは、複数の漏洩点からそれぞれ
の検出点までの距離差による到達時間の差によって生じ
るもので、互いに干渉を与えない。漏洩点が複数存在す
る場合でも、それぞれの検出点間から求めた双曲線が同
時に交差する点を選べば、実在しうる点を同時に判定す
る事ができる。
Next, a case where a plurality of leak points exist at the same time will be described. Leakage sound generated from another leak point,
The cross-correlation functions are independent white noises, and each leaked sound is captured independently, and the cross-correlation function calculated based on these noises has no large value anywhere. That is, the plurality of peaks generated in the cross-correlation function of each detection point are caused by differences in arrival time due to the difference in distance from the plurality of leak points to each detection point, and do not interfere with each other. Even when there are a plurality of leak points, if a point where the hyperbolas obtained from the respective detection points intersect at the same time is selected, it is possible to determine the points that can actually exist at the same time.

【0015】これまでは説明を簡単にするため、漏洩点
より検出点まで音波が直進するものとして扱ってきた。
実際には、配管もしくは缶体等において、音波が、漏洩
点から検出点に伝播する経路は複数存在し、その経路長
は一般に異なる。また配管端で反射もある。このため単
純に各検出点の相互相関関数を計算してしまうと、偽の
漏洩点を検出してしまう。漏洩音は白色雑音である事を
前提としたが、複数の経路や反射がある場合、検出点に
現れる音波は、漏洩点での音波を、経路差による時間差
eをずらして加え合わせたものとなり、その自己相関
関数は、τ=0以外に、τ=te にもピークを生じるた
めである。
Until now, for simplicity, it has been assumed that the sound wave travels straight from the leak point to the detection point.
Actually, in a pipe, a can, or the like, there are a plurality of paths through which sound waves propagate from a leak point to a detection point, and the path lengths are generally different. There is also reflection at the pipe end. Therefore, if the cross-correlation function of each detection point is simply calculated, a false leak point will be detected. Those leaked sound has been assumed to be a white noise, if there are multiple paths and reflections, waves appearing in detection points, in which the sound waves at the leakage point, the combined added by shifting the time difference t e by the path difference next, the autocorrelation function, in addition to tau = 0, to tau = t e is to produce a peak.

【0016】この問題を解決するには、一般にエコーキ
ャンセルと言われる、適応フィルタの応用技術を利用す
る。適応フィルタの構成法は様々なものが提唱されてお
り、もちろん本発明に組み合わせることも可能だが、漏
洩音は白色雑音である事が分かっているので、もっとも
単純に、検出点に現れる音波を白色雑音に戻すフィルタ
を構成できれば良い。これは最大エントロピー法(MEM
- Maximum Entropy Method) によって得られる予測誤差
フィルタにほかならない。相互相関関数は、このフィル
タに検出器の信号を通したものの出力を使って計算すれ
ばよい。
In order to solve this problem, an applied technique of an adaptive filter, which is generally called echo cancellation, is used. A variety of adaptive filter configuration methods have been proposed and can be combined with the present invention. Of course, since it is known that the leaked sound is white noise, the simplest method is to convert the sound wave that appears at the detection point into white noise. It suffices if a filter that restores noise can be configured. This is the maximum entropy method (MEM
-It is nothing but a prediction error filter obtained by the Maximum Entropy Method). The cross-correlation function may be calculated using the output of the filter passed through the detector signal.

【0017】これまでの説明において、各音波検出器の
信号は、同時にサンプリングされることを前提としてい
たが、既知の時間差があっても、最終的に得られた計算
結果についてこの時間差を補正することにより、同時に
サンプリングされたのと同一の結果が得られるのは明ら
かである。この事実は、実現に当たりサンプルホールド
回路もしくはADコンバータを音波検出器の数だけ用意
しなくても、マルチプレクサによって、1台のADコン
バータを各音波検出器につなぎかえ、時分割的に信号を
取り込むことが出来るわけであり、装置の簡略化に貢献
する。
In the above description, it has been assumed that the signals of the respective sound wave detectors are sampled at the same time. Even if there is a known time difference, the time difference is corrected with respect to the finally obtained calculation result. Obviously, this gives the same result as being sampled simultaneously. The fact is that even if the sample-and-hold circuits or AD converters are not prepared by the number of sound wave detectors in realization, one AD converter is connected to each sound wave detector by a multiplexer and signals are captured in a time-division manner. This contributes to simplification of the device.

【0018】本発明において、距離差は、音波の到達時
間の差として測定されることは前述した。音速は媒体、
温度により一般に異なる値となる。すなわち、これまで
述べた方法によると、音速の変化は、推定した漏洩点の
方向に対し大きな影響はないが、その距離には誤差を生
じることになる。この問題は、次に述べる方法をこれま
で述べた方法に組み合わせることにより、解決すること
が出来る。
As described above, in the present invention, the distance difference is measured as a difference between arrival times of sound waves. Sound speed is medium,
The value generally varies depending on the temperature. That is, according to the method described so far, the change in the sound speed does not greatly affect the estimated direction of the leak point, but causes an error in the distance. This problem can be solved by combining the method described below with the method described above.

【0019】本発明に用いる音波検出器は、具体的に
は、固体中を伝播する音波を捉え易いよう工夫された圧
電素子、ダイナミックマイク等を用いる。これらは、逆
に電力を外部から供給すると、音波発信器として作用す
る。そこで、複数個の音波検出器より1個を順次選択
し、これを音波発信器として使い、識別容易な信号を音
波として発生させる。残りの音波検出器で、この音波を
捉え、発信した信号との相互相関関数を求めれば、音波
発信器からの到達時間に対応するラグにピークを生じる
ので、音速を求めることが出来る。求めた音速によっ
て、漏洩音の音速の変化による距離の誤差を校正するこ
とができる。好適な信号としては、疑似ランダム信号の
M系列信号が挙げられる。M系列信号は、白色雑音と等
価な数学的性質を持つため、漏洩音と同様の処理が出
来、かつ、漏洩音自身と干渉しないため、漏洩音が既に
生じている実測定状態でも、音速を測定できる。また、
M系列信号は、0,1のいずれかの状態をとる二値信号
であるため、駆動用パワーアンプは直線性が不要で、簡
便かつ安価に製作できる。こうして、漏洩点からの音波
を捉える動作と、音速を測定する動作を適宜切り換えな
がら行えば、音速による誤差を取り除き、漏洩点の位置
を高精度に判定できる。
As the sound wave detector used in the present invention, specifically, a piezoelectric element, a dynamic microphone, or the like designed to easily catch sound waves propagating in a solid is used. On the contrary, when electric power is supplied from the outside, they function as sound wave transmitters. Therefore, one is sequentially selected from a plurality of sound wave detectors, and this is used as a sound wave transmitter to generate easily identifiable signals as sound waves. If the remaining sound wave detector captures the sound wave and calculates a cross-correlation function with the transmitted signal, a peak occurs at a lag corresponding to the arrival time from the sound wave transmitter, so that the sound speed can be obtained. The error of the distance due to the change in the sound speed of the leaked sound can be calibrated based on the obtained sound speed. An example of a suitable signal is an M-sequence signal of a pseudo-random signal. Since the M-sequence signal has mathematical properties equivalent to white noise, the same processing as leaked sound can be performed, and since it does not interfere with the leaked sound itself, the sound speed can be reduced even in an actual measurement state where leaked sound has already occurred. Can be measured. Also,
Since the M-sequence signal is a binary signal that takes one of the states 0 and 1, the driving power amplifier does not require linearity and can be manufactured simply and inexpensively. In this way, if the operation of capturing the sound wave from the leak point and the operation of measuring the sound speed are appropriately switched, the error due to the sound speed can be removed, and the position of the leak point can be determined with high accuracy.

【0020】[0020]

【実施例】以下、実施例を示して本発明についてさらに
具体的に説明する。 実施例1 図4は本発明を2検出点で実施した場合のプローブ10
(漏洩箇所検出装置)の例である。図中、符号11a,
11bは音波検出器、14は判定結果を表示する表示器
で本実施例ではLED(発光ダイオード)を用いてい
る。図5は、この実施例でのブロック図である。音波検
出器11a,11bからの出力信号は適応フィルタを通
した後、ADコンバータ12によってデジタル信号に変
換し、これをDSP(デジタルシグナルプロセッサ)1
3により前記したように相互相関関数を数値計算し、漏
洩点の方向を判定し、表示器14に表示する。適応フィ
ルタは、MEMを用いて計算する。また、相互相関関数
は、FFT法、ブラックマン−チューキィ(Blackman-T
ukey)法等で計算する。これらの計算は、すべてDSP
等の高速CPUによりデジタル演算として実現される。
音波検出器11a,11bを漏洩がある配管もしくは缶
体に接触させると、漏洩点に近い方向のLEDが点灯す
るので、プローブ10をその方向へ移動する。中央のL
EDが点灯すれば、音波検出器の間に漏洩点があること
を示す。
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. Embodiment 1 FIG. 4 shows a probe 10 when the present invention is implemented at two detection points.
It is an example of a (leakage point detection device). In the figure, reference numerals 11a,
Reference numeral 11b denotes a sound wave detector, and reference numeral 14 denotes a display for displaying a determination result. In this embodiment, an LED (light emitting diode) is used. FIG. 5 is a block diagram in this embodiment. Output signals from the sound wave detectors 11a and 11b pass through an adaptive filter, and are converted into digital signals by an AD converter 12, which converts the signals into a DSP (digital signal processor) 1
As described above, the numerical value of the cross-correlation function is calculated by 3 and the direction of the leak point is determined and displayed on the display 14. The adaptive filter is calculated using MEM. The cross-correlation function can be calculated by the FFT method or the Blackman-Tulky method.
ukey) calculation. These calculations are all performed by the DSP
Is realized as a digital operation by a high-speed CPU.
When the sound wave detectors 11a and 11b are brought into contact with a leaking pipe or can body, an LED in a direction near the leak point is turned on, and the probe 10 is moved in that direction. Central L
When the ED lights up, it indicates that there is a leak point between the sound wave detectors.

【0021】実施例2 図6は、本発明を3検出点において実施した例のプロー
ブ20である。本実施例では符号21a,21b,21
cが音波検出器、26は判定結果を表示する表示器で本
実施例ではグラフィックLCD(液晶表示装置)を用い
ている。ブロック図は、図7に示す。図中、21a,2
1b,21cは音波検出器、22a,22b,22cは
DSPで制御されるアナログスイッチ、23はADコン
バータ、24はDSP、25は1つの音波検出器を音波
発信器として利用するときの駆動用パワーアンプ、26
は表示器であるグラフィックLCDユニットを表わす。
音波検出器21a,21b,21cを漏洩がある配管も
しくは缶体に直接接触させるか、これが埋設された地表
に接触させると、LCD表示器26に相対的な距離と方
向が矢印で表示されるので、プローブ20をその方向へ
移動し、漏洩点を探索する。本実施例では同時に複数の
漏洩点があっても、分離して表示できる。また、音波検
出器を音波発信器と兼用し、該音波発信器から発信され
た音波信号に基づき音速を測定しつつ、漏洩点を判定す
るため、音速による誤差は生じず、高精度の判定が可能
である。
Embodiment 2 FIG. 6 shows a probe 20 in which the present invention is implemented at three detection points. In this embodiment, reference numerals 21a, 21b, 21
c is a sound wave detector, and 26 is a display for displaying the determination result. In this embodiment, a graphic LCD (liquid crystal display) is used. The block diagram is shown in FIG. In the figure, 21a, 2
1b and 21c are sound wave detectors, 22a, 22b and 22c are analog switches controlled by a DSP, 23 is an AD converter, 24 is a DSP, and 25 is driving power when one sound wave detector is used as a sound wave transmitter. Amplifier, 26
Represents a graphic LCD unit as a display.
If the sound wave detectors 21a, 21b and 21c are brought into direct contact with the leaking pipe or can body or with the buried ground surface, the relative distance and direction are indicated by arrows on the LCD display 26. The probe 20 is moved in that direction to search for a leak point. In this embodiment, even if there are a plurality of leak points at the same time, they can be displayed separately. In addition, since the sound wave detector is also used as a sound wave transmitter, and the sound point is measured based on the sound wave signal transmitted from the sound wave transmitter and the leak point is determined, an error due to the sound speed does not occur. It is possible.

【0022】[0022]

【発明の効果】以上にように、本発明により、だれでも
容易にかつ確実に漏洩箇所を検知し特定できる装置が提
供される。本発明の漏洩箇所検出方式は装置化が容易
で、当業者であれば誰でも簡単に具現化し、製品化でき
る。本発明は、従来方法及び装置では実現不能な配管等
の漏洩箇所検出装置を提供することによって、産業上、
漏洩箇所検出の労力と危険を減少するのみならず、流体
配管もしくは缶体からの流体流出事故の防止や資源の節
約に多大に貢献することができる。
As described above, according to the present invention, there is provided an apparatus capable of easily and surely detecting and specifying a leak location. The leak location detection method of the present invention is easy to implement as a device, and any person skilled in the art can easily realize and commercialize it. Industrial Applicability The present invention provides an apparatus for detecting a leak point such as a pipe which cannot be realized by a conventional method and apparatus, and
This not only reduces the labor and danger of leak point detection, but also greatly contributes to prevention of fluid outflow accidents from fluid pipes or can bodies and resource saving.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の作用を説明するための漏洩点と2つの
検出点の配置例を示す模式図である。
FIG. 1 is a schematic diagram showing an example of the arrangement of a leak point and two detection points for explaining the operation of the present invention.

【図2】相互相関関数の変位の経時変化と相関関数曲線
との関係を示すグラフである。
FIG. 2 is a graph showing a relationship between a temporal change in displacement of a cross-correlation function and a correlation function curve.

【図3】検出点が3点の場合の各点への距離差が等しく
なる双曲線を表わすグラフである。
FIG. 3 is a graph showing a hyperbola in which the distance difference to each point is equal when the number of detected points is three.

【図4】本発明の漏洩箇所検出装置を2検出点で実施し
た実施例のプローブの概略構成図である。
FIG. 4 is a schematic configuration diagram of a probe of an embodiment in which the leakage point detection device of the present invention is implemented at two detection points.

【図5】本発明の漏洩箇所検出装置を2検出点で実施し
た実施例のブロック図である。
FIG. 5 is a block diagram of an embodiment in which the leakage point detection device of the present invention is implemented at two detection points.

【図6】本発明の漏洩箇所検出装置を3検出点で実施し
た実施例のプローブの概略構成図である。
FIG. 6 is a schematic configuration diagram of a probe of an embodiment in which the leakage point detection device of the present invention is implemented at three detection points.

【図7】本発明の漏洩箇所検出装置を3検出点で実施し
た実施例のブロック図である。
FIG. 7 is a block diagram of an embodiment in which the leakage point detection device of the present invention is implemented at three detection points.

【符号の説明】[Explanation of symbols]

10,20 プローブ(漏洩箇所検出装置) 11a,11b,21a,21b,21c 音波検出器 12,23 ADコンバータ 13,24 DSP 14 表示器(LED) 25 駆動用パワーアンプ 26 表示器(グラフィックLCD) 10, 20 Probe (leakage point detecting device) 11a, 11b, 21a, 21b, 21c Sound wave detector 12, 23 AD converter 13, 24 DSP 14 Display (LED) 25 Driving power amplifier 26 Display (graphic LCD)

Claims (4)

【特許請求の範囲】[Claims] 【請求項1】 2個以上の音波検出器を一定距離を保っ
て支持する可動式プローブとして構成され、漏洩箇所か
ら伝播する漏洩音を検出する音波検出器と、該音波検出
器の出力を、同時もしくは既知の時間差をもってADコ
ンバータでサンプリングし、その相互相関関数を数値計
算することによって、配管もしくは缶体の漏洩点の方向
を判定し、表示する手段とを有することを特徴とする漏
洩箇所検出装置。
1. A sound probe that is configured as a movable probe that supports two or more sound wave detectors at a fixed distance, detects a sound leaking from a leak location, and outputs an output of the sound wave detector. Means for sampling at the same time or with a known time difference by an AD converter, and calculating the cross-correlation function thereof to determine the direction of the leak point of the pipe or can body, and displaying the leak point. apparatus.
【請求項2】 3個以上の音波検出器を相互に一定距離
を保って支持する可動式プローブとして構成され、漏洩
箇所から伝播する漏洩音を検出する音波検出器と、該音
波検出器の出力を、同時もしくは既知の時間差をもって
ADコンバータでサンプリングし、その相互相関関数を
数値計算することによって、各検出器から漏洩点までの
距離差を算出し、配管もしくは缶体の漏洩点の方向及び
位置を、該音波検出器位置を焦点とする双曲線の交点と
して判定し、表示する手段とを有することを特徴とする
漏洩箇所検出装置。
2. A sound wave detector configured to support three or more sound wave detectors at a certain distance from each other and detect a leaked sound propagating from a leak location, and an output of the sound wave detector. Is sampled by an AD converter at the same time or with a known time difference, and the cross-correlation function is numerically calculated to calculate the distance difference from each detector to the leak point, and the direction and position of the leak point of the pipe or can body And a means for determining and displaying an intersection of hyperbolas having the position of the sound wave detector as a focal point.
【請求項3】 相互相関関数を計算する前処理として各
検出器の出力信号に対して適用するために、最大エント
ロピー法の予測誤差フィルタを用いた適応フィルタをさ
らに備える請求項1又は2に記載の漏洩箇所検出装置。
3. The adaptive filter according to claim 1, further comprising an adaptive filter using a prediction error filter of a maximum entropy method, for applying the cross-correlation function to the output signal of each detector as a pre-process for calculating the cross-correlation function. Leakage point detection device.
【請求項4】 音波検出器を音波発信器として兼用し、
音波検出器の互いの相対的距離を校正することを特徴と
する請求項1乃至3のいずれか一項に記載の漏洩箇所検
出装置。
4. A sound wave detector also serving as a sound wave transmitter,
The leak location detecting device according to claim 1, wherein a relative distance between the acoustic wave detectors is calibrated.
JP35260996A 1996-12-16 1996-12-16 Detecting device for leak place Pending JPH10176970A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP35260996A JPH10176970A (en) 1996-12-16 1996-12-16 Detecting device for leak place

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP35260996A JPH10176970A (en) 1996-12-16 1996-12-16 Detecting device for leak place

Publications (1)

Publication Number Publication Date
JPH10176970A true JPH10176970A (en) 1998-06-30

Family

ID=18425219

Family Applications (1)

Application Number Title Priority Date Filing Date
JP35260996A Pending JPH10176970A (en) 1996-12-16 1996-12-16 Detecting device for leak place

Country Status (1)

Country Link
JP (1) JPH10176970A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002340723A (en) * 2001-05-18 2002-11-27 High Pressure Gas Safety Institute Of Japan Method for sensing gas leakage
JP2008292338A (en) * 2007-05-25 2008-12-04 Mori Engineering:Kk Leakage detector
WO2013145492A1 (en) * 2012-03-30 2013-10-03 日本電気株式会社 Leak detection method, water leakage detection method, leak detection device, and water leakage detection device
WO2020095538A1 (en) * 2018-11-08 2020-05-14 株式会社日立製作所 Water leakage detection method, water leakage detection system, and sensor terminal used in same
CN111465373A (en) * 2017-12-22 2020-07-28 科洛普拉斯特公司 Ostomy system and monitoring device with angular leak detection

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002340723A (en) * 2001-05-18 2002-11-27 High Pressure Gas Safety Institute Of Japan Method for sensing gas leakage
JP2008292338A (en) * 2007-05-25 2008-12-04 Mori Engineering:Kk Leakage detector
WO2013145492A1 (en) * 2012-03-30 2013-10-03 日本電気株式会社 Leak detection method, water leakage detection method, leak detection device, and water leakage detection device
JP2013210347A (en) * 2012-03-30 2013-10-10 Nec Corp Leakage detection method, water leakage detection method, leakage detector and water leakage detector
CN111465373A (en) * 2017-12-22 2020-07-28 科洛普拉斯特公司 Ostomy system and monitoring device with angular leak detection
WO2020095538A1 (en) * 2018-11-08 2020-05-14 株式会社日立製作所 Water leakage detection method, water leakage detection system, and sensor terminal used in same
JP2020076646A (en) * 2018-11-08 2020-05-21 株式会社日立製作所 Water leakage detection method, water leakage detection system, and sensor terminal used therefor

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