JP2001249085A - Method and apparatus for inspecting sewer pipe - Google Patents
Method and apparatus for inspecting sewer pipeInfo
- Publication number
- JP2001249085A JP2001249085A JP2000059108A JP2000059108A JP2001249085A JP 2001249085 A JP2001249085 A JP 2001249085A JP 2000059108 A JP2000059108 A JP 2000059108A JP 2000059108 A JP2000059108 A JP 2000059108A JP 2001249085 A JP2001249085 A JP 2001249085A
- Authority
- JP
- Japan
- Prior art keywords
- electromagnetic wave
- sewer
- frequency
- signal
- abnormality
- 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
- Sewage (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、電磁波を用いて上
下水等の管渠に生じる異常を検出する管渠検査方法及び
その装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewer inspection method and apparatus for detecting an abnormality occurring in a sewer such as water supply and drainage using electromagnetic waves.
【０００２】[0002]
【従来の技術】上下水等の管渠では管内に異物が入り込
んだり、管が破損する等の敷設異常が発生する場合があ
る。これらの異常検査を実施する場合、大口径の管であ
れば人間が管内を探索することが可能であるが、人間が
入ることのできる大口径管渠は実際には少数であり、大
多数の管渠は人間による探索を行うことができない。そ
のため、小口径管渠を点検する場合、現在は管内を洗浄
した後、テレビカメラを搭載した小型の管内走行車を用
いて管内を撮影しながら点検する方法が主に用いられて
いる。しかし、この方法では、まず管内を洗浄する必要
がある上、その後の管内撮影検査にかかる労力が大き
く、検査に要する小口径管渠のうちごく一部しか検査が
行われていないのが現状である。2. Description of the Related Art In a sewer such as water supply and sewerage, there is a case where a laying abnormality such as entry of foreign matter into the pipe or breakage of the pipe occurs. When conducting these abnormal inspections, it is possible for humans to search inside the pipe if it is a large-diameter pipe, but the number of large-diameter pipes that humans can enter is actually small, Sewers cannot be searched by humans. For this reason, when inspecting a small-diameter sewer, a method is currently mainly used in which the inside of a pipe is washed and then inspected while photographing the inside of the pipe using a small in-pipe traveling vehicle equipped with a television camera. However, in this method, it is necessary to first clean the inside of the pipe, and the labor involved in the subsequent inspection of the inside of the pipe is large, and at present, only a small portion of the small-diameter sewer required for the inspection is inspected. is there.
【０００３】そこで、長距離、広範囲の検査を短時間で
実施する方法として電磁波を用いた管渠検査方法が提唱
されており、この種の従来方法としては、例えば、図９
（以下、これを第１の従来技術と言う）や出典特開平１
０−５４７０２号公報（以下、これを第２の従来技術と
言う）に記載されたものがある。これらの従来方法で
は、共に管内に電磁波を送信し、敷設異常を反映した受
信情報を基に異常の検出・診断を行っている。[0003] Therefore, a sewer inspection method using electromagnetic waves has been proposed as a method for performing a long-distance, wide-area inspection in a short time. As a conventional method of this kind, for example, FIG.
(Hereinafter, this is referred to as the first prior art)
Japanese Patent Application Laid-Open No. 0-54702 (hereinafter referred to as a second prior art) is available. In these conventional methods, both transmit an electromagnetic wave to the inside of the pipe, and detect and diagnose an abnormality based on received information reflecting the laying abnormality.
【０００４】図９の第１の従来技術を説明する。この従
来技術は、地下埋設管渠を測定対象とし、測定対象管渠
３１に電磁波送信手段３３並びに電磁波受信手段３５を
挿入して電磁波の送・受信を行っている。電磁波送・受
信手段３３，３５以外の高周波発生手段３２、信号解析
手段３６及び出力手段３７は測定対象管渠３１の外に配
置し、管渠内反射物３４で反射して電磁波受信手段３５
で受信された受信信号から得られる情報を信号解析手段
３６で解析し、出力手段３７からの出力をみて管渠検査
を行っている。[0004] A first prior art of FIG. 9 will be described. In this prior art, an electromagnetic wave transmitting means 33 and an electromagnetic wave receiving means 35 are inserted into a measurement target culvert 31 to transmit and receive electromagnetic waves. The high-frequency generating means 32, the signal analyzing means 36 and the output means 37 other than the electromagnetic wave transmitting / receiving means 33 and 35 are arranged outside the measuring pipe 31 and are reflected by the reflector 34 in the pipe and reflected by the electromagnetic wave receiving means 35.
The information obtained from the received signal is analyzed by the signal analyzing means 36, and the output from the output means 37 is checked to check the sewerage.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、上記従
来技術が提唱された段階では、管内の電磁波伝搬の様相
がわかっておらず、また使用する電磁波の周波数や装置
のブロック構成等の具体的方法が確立されていなかっ
た。However, at the stage when the above-mentioned prior art was proposed, the manner of electromagnetic wave propagation in the pipe was not known, and the specific method such as the frequency of the electromagnetic wave to be used and the block configuration of the device was not known. Had not been established.
【０００６】まず、第１の問題点として、従来は管渠を
導波管と見なしており、管の口径で決まる遮断周波数よ
り高い周波数を用いれば測定を行えると考えていた。し
かしながら実際の管渠、特にヒューム管における管内周
波数特性は導波管とは大きく異なる。仮に円筒形の管渠
を円形導波管と見なした場合、遮断周波数より高い周波
数を持つ電磁波が管内を伝搬することができる。理論に
よれば光速度をｃ、管内の半径をａとした場合、円形導
波管の遮断周波数ｆ0 は次式で表される。First, as a first problem, a pipe is conventionally regarded as a waveguide, and it has been thought that measurement can be performed by using a frequency higher than a cutoff frequency determined by the pipe diameter. However, the frequency characteristics in an actual pipe, especially in a fume pipe, are significantly different from those of a waveguide. If a cylindrical conduit is regarded as a circular waveguide, an electromagnetic wave having a frequency higher than the cutoff frequency can propagate in the tube. According to the theory, when the light speed is c and the radius in the tube is a, the cutoff frequency f 0 of the circular waveguide is expressed by the following equation.
【０００７】 ｆ0 ＝ｃ／３．４１３ ａ …（１） ここで、管の口径即ち直径が１５０ｍｍの場合を計算す
ると遮断周波数ｆ0 は１．１７ＧＨｚとなり、それ以上
の周波数であれば管内を減衰することなく伝搬すること
ができることになる。しかし、実際の管渠は導波管とは
大きく異なる特性を示すことが本発明に関する研究過程
で明らかとなった。F 0 = c / 3.413 a (1) Here, when the caliber of the tube, that is, the diameter is 150 mm, is calculated, the cutoff frequency f 0 is 1.17 GHz. It can be propagated without attenuation. However, it has been clarified in the course of the research relating to the present invention that an actual sewer exhibits characteristics significantly different from those of a waveguide.
【０００８】実際のヒューム管内にマイクロ波帯（Ｘバ
ンド）、ミリ波帯（Ｒバンド）の電磁波を伝搬させた場
合の管内減衰特性を図１０にまとめて示す。ヒューム管
はＪＩＳ Ａ ５３０３ Ｂ型管、呼び径１５０ｍｍを使
用している。呼び径は管の内径に等しい。図１０から明
らかなように、内径１５０ｍｍのヒューム管では、１０
ＧＨｚ以下の電磁波は直ぐに減衰してしまい、遠方まで
伝搬することはない。この傾向は低周波側ほど顕著であ
る。これに対し遮断周波数の約１０倍である１２ＧＨｚ
付近から電磁波の減衰率は低下し、これにより高周波側
では遠方まで伝搬するようになる。ヒューム管の検査も
しくは診断等に電磁波を用いる場合、遮断周波数に近い
周波数の電磁波を用いても直ぐに減衰してしまい、ごく
短距離の検査しか行うことができない。一例をあげる
と、呼び径１５０ｍｍのヒューム管に１０ＧＨｚのマイ
クロ波を送信して実際に測定を行ったが、この場合の最
大検査距離はたかだか５ｍ程度である。FIG. 10 shows the attenuation characteristics in a tube when electromagnetic waves in the microwave band (X band) and the millimeter wave band (R band) are propagated in an actual fume tube. The fume pipe uses a JIS A 5303 B type pipe with a nominal diameter of 150 mm. The nominal diameter is equal to the inner diameter of the tube. As is clear from FIG. 10, in a fume tube having an inner diameter of 150 mm, 10
Electromagnetic waves below GHz are immediately attenuated and do not propagate far. This tendency is more remarkable on the lower frequency side. On the other hand, 12 GHz which is about 10 times the cutoff frequency
From the vicinity, the attenuation rate of the electromagnetic wave decreases, so that the electromagnetic wave propagates far away on the high frequency side. When an electromagnetic wave is used for inspection or diagnosis of a fume tube, even if an electromagnetic wave having a frequency close to the cutoff frequency is used, it is immediately attenuated, and only a very short distance inspection can be performed. To give an example, a 10 GHz microwave was transmitted to a fume tube with a nominal diameter of 150 mm to actually measure, but the maximum inspection distance in this case was at most about 5 m.
【０００９】第２の問題点として、第２の従来技術では
管渠を電波漏洩のある伝送路と仮定するか、あるいは導
波管と仮定するなどして議論を行っているが、当時は管
渠内の電磁波伝搬特性に不明な点が多く、電磁波の使用
法が明確化されていなかった。しかし、その後の測定に
より管渠内の電磁波伝搬特性は導波管や伝送線の理論か
ら導かれる結果とはかなり異なっていることが判明して
きた。先に述べたヒューム管内における電磁波減衰はそ
の最も顕著な例である。遮断周波数より遥かに高い周波
数でも大きな減衰が生じることは導波管の理論では説明
することができない。また従来は、管渠を一種の伝送線
と考えていたため、管のひび割れ等も検査対象としてい
るが、実際に測定対象となる物体は電磁波波長よりも寸
法の大きいものであり、小さなひび割れは現実には測定
困難である。また、本発明に関わる研究の過程でヒュー
ム管の接続部も殆ど観測されないことが判明している。
そして管内異物等による反射電磁波を受信する方法が管
内検査方法として最も適していることが判明した。そこ
で、反射計測方式を基本として管渠検査に適した測定方
式と装置構成を明らかにすることが本発明の目的の１つ
である。[0009] As a second problem, in the second prior art, discussions have been made assuming that a sewer is a transmission line with radio wave leakage or a waveguide. There are many unclear points about the electromagnetic wave propagation characteristics in the culvert, and the usage of electromagnetic waves has not been clarified. However, subsequent measurements have revealed that the electromagnetic wave propagation characteristics in the sewer differ significantly from the results derived from the theory of waveguides and transmission lines. The aforementioned electromagnetic wave attenuation in the fume tube is the most prominent example. The fact that significant attenuation occurs at frequencies much higher than the cut-off frequency cannot be explained by waveguide theory. In the past, pipes were considered as a kind of transmission line, so cracks in pipes were also inspected.However, the actual object to be measured was larger than the wavelength of electromagnetic waves, and small cracks were Is difficult to measure. In the course of the research relating to the present invention, it has been found that the connection of the fume tube is hardly observed.
And it turned out that the method of receiving the reflected electromagnetic wave by the foreign substance in a pipe | tube is the most suitable as a pipe | tube inspection method. Therefore, it is an object of the present invention to clarify a measuring method and a device configuration suitable for sewer inspection based on a reflection measuring method.
【００１０】第３の問題点として、実際に管渠内部に対
して電磁波の送・受信を行う場合の装置構成の問題があ
る。従来は管渠を導波管と見なした場合の遮断周波数以
上であれば使用可能であると考えられていた。そしてア
ンテナ等の送・受信手段のみを管内に挿入し、その他の
機構は管渠の外に配置する構成をとっていた。しかしな
がら、第１の問題点で述べたとおり、実際には遮断周波
数よりも十分に高い周波数の電磁波を用いなければ遠方
までの測定は行うことができない。すると送・受信手段
と他の機構を接続する信号線に低周波用の電線を用いる
ことができなくなり、高周波用同軸ケーブルを使用する
必要が生じる。マイクロ波帯の信号を伝送する場合はマ
イクロ波用の高周波ケーブルを使用すればある程度の距
離を伝送させることが可能であるが、３０ＧＨｚ以上の
ミリ波帯の信号を伝送するためには導波管やマイクロス
トリップ線路、ＮＲＤガイドなどケーブルとは異なる技
術が必要となる。これらは全て固定された伝送路であ
り、曲げることは困難であるからミリ波帯を用いる場合
は従来の構成を採用すること自体が困難となる。[0010] As a third problem, there is a problem in the device configuration when electromagnetic waves are actually transmitted / received to / from the inside of a sewer. Conventionally, it has been considered that the sewer can be used if the cutoff frequency is equal to or higher than the cutoff frequency when the sewer is regarded as a waveguide. Then, only the transmitting / receiving means such as an antenna is inserted into the pipe, and the other mechanisms are arranged outside the sewer. However, as described in the first problem, measurement to a distant place cannot be performed unless an electromagnetic wave having a frequency sufficiently higher than the cutoff frequency is actually used. Then, a low-frequency electric wire cannot be used as a signal line connecting the transmission / reception means and another mechanism, and it becomes necessary to use a high-frequency coaxial cable. When transmitting signals in the microwave band, it is possible to transmit a certain distance by using a high-frequency cable for microwaves. However, in order to transmit signals in the millimeter wave band of 30 GHz or more, a waveguide is used. And a technique different from a cable such as a microstrip line and an NRD guide. Since these are all fixed transmission lines and are difficult to bend, it is difficult to adopt the conventional configuration itself when using the millimeter wave band.
【００１１】また、第４の問題点として、電磁波には偏
波の性質があるため、方向性を持つ物体はその方向によ
り検出感度が大きく異なる。例として管内異物として金
属線が置かれた場合を考え、直線偏波した電磁波を送信
して金属線が検出できるかどうかを考察する。金属線の
向きが偏波方向と等しい場合は電磁波と金属線の相互作
用は最大となり、強い反射が得られるため金属線は容易
に検出される。しかし金属線と偏波の向きが互いに垂直
である場合、金属線は電磁波と相互作用しないため反射
が起こらない。この問題を解決するためには測定対象物
の向きに電磁波の偏波方向を合わせる機構を装置に付加
する必要がある。As a fourth problem, since electromagnetic waves have the property of polarization, the sensitivity of an object having directionality varies greatly depending on the direction. As an example, consider a case where a metal wire is placed as a foreign substance in a pipe, and consider whether a metal wire can be detected by transmitting a linearly polarized electromagnetic wave. When the direction of the metal wire is equal to the polarization direction, the interaction between the electromagnetic wave and the metal wire is maximized, and strong reflection is obtained, so that the metal wire is easily detected. However, when the metal wire and the polarization direction are perpendicular to each other, no reflection occurs because the metal wire does not interact with the electromagnetic wave. In order to solve this problem, it is necessary to add a mechanism for adjusting the polarization direction of the electromagnetic wave to the direction of the object to be measured.
【００１２】本発明は、上記に鑑みてなされたもので、
長距離の管渠でも一度に検査することができ、長距離の
管渠でも管渠内の異常発生位置を特定することができ、
高周波における伝送路減衰を低減させることができ、ま
た長距離の管渠内で方向性を持つ被検査物を確実に検出
することができる管渠検査方法及びその装置を提供する
ことを目的とする。The present invention has been made in view of the above,
Even long-distance culverts can be inspected at once, and even in long-distance culverts, it is possible to identify the location of abnormalities in the culvert,
It is an object of the present invention to provide a sewer inspection method and apparatus capable of reducing transmission line attenuation at high frequencies and reliably detecting a test object having directionality in a long sewer. .
【００１３】[0013]
【課題を解決するための手段】上記課題を解決するため
に、請求項１記載の管渠検査方法は、電磁波を用いて上
下水等の管渠に生じた異常を検出する管渠検査方法にお
いて、前記電磁波の周波数を、前記管渠を導波管と見な
した場合の遮断周波数に対して１０倍以上としたことを
要旨とする。この構成により、管渠内に入射された電磁
波は殆ど減衰することなく遠方まで伝搬し、被検査物で
反射した電磁波を受信し、信号解析を行うことで管渠内
に生じた異常が検出される。管渠特にヒューム管を検査
対象とした場合、管渠を導波管と見なしたときの遮断周
波数に対し１０倍以下の周波数を持つ電磁波は、管渠内
で急速に減衰し、遠方まで伝搬しない。According to a first aspect of the present invention, there is provided a sewer inspection method for detecting an abnormality in a sewer such as water supply and drainage using electromagnetic waves. The gist of the invention is that the frequency of the electromagnetic wave is at least 10 times the cutoff frequency when the conduit is regarded as a waveguide. With this configuration, the electromagnetic wave incident into the sewer propagates to the distant place with almost no attenuation, receives the electromagnetic wave reflected by the test object, and performs signal analysis to detect abnormalities that occurred in the sewer. You. When inspecting sewers, especially fume pipes, electromagnetic waves having a frequency less than 10 times the cutoff frequency when the sewer is regarded as a waveguide are rapidly attenuated in the sewer and propagate to distant places. do not do.
【００１４】請求項２記載の管渠検査装置は、電磁波を
用いて上下水等の管渠に生じた異常を検出する管渠検査
装置において、前記管渠を導波管と見なした場合の遮断
周波数に対し１０倍以上の周波数を持つ電磁波を発生す
る高周波発生手段と、この高周波発生手段で発生した電
磁波に変調情報を加える変調手段と、前記管渠内に前記
変調情報を加えた電磁波を送信する送信手段と、前記管
渠内の異物又は敷設異常等により反射された電磁波を受
信する受信手段と、この受信手段の受信信号を検波して
検波信号とする検波手段と、前記検波信号に対し送信電
磁波に与えた前記変調情報を基に信号解析を行うことに
より異常検出を行う信号解析手段とを有することを要旨
とする。この構成により、管渠内に変調情報を加えた電
磁波を入射させることで、反射電磁波を検波した検波信
号には被検査物までの距離を反映した情報が含まれる。
このため、検波信号を信号解析することにより被検査物
までの距離、即ち管渠内の異物又は敷設異常等の異常発
生位置を特定することが可能となる。According to a second aspect of the present invention, there is provided a sewer inspection apparatus for detecting an abnormality generated in a sewer such as water supply and sewerage using electromagnetic waves, wherein the sewer is regarded as a waveguide. High frequency generating means for generating an electromagnetic wave having a frequency 10 times or more higher than the cutoff frequency, modulating means for adding modulation information to the electromagnetic wave generated by the high frequency generating means, and electromagnetic wave obtained by adding the modulation information to the inside of the pipe. Transmitting means for transmitting, receiving means for receiving electromagnetic waves reflected by foreign matter or laying abnormality in the sewer, detecting means for detecting a received signal of the receiving means to make a detected signal, and detecting the detected signal. On the other hand, the gist of the present invention is to include signal analysis means for detecting an abnormality by performing a signal analysis based on the modulation information given to the transmission electromagnetic wave. With this configuration, the electromagnetic wave to which the modulation information is added is incident on the inside of the pipe, and the detection signal obtained by detecting the reflected electromagnetic wave includes information reflecting the distance to the inspection object.
Therefore, by analyzing the detected signal, it is possible to specify the distance to the inspection object, that is, the position where an abnormality such as a foreign substance in the sewer or a laying abnormality occurs.
【００１５】請求項３記載の管渠検査装置は、上記請求
項２記載の管渠検査装置において、前記変調手段は、周
波数制御手段であり、前記管渠内に送信する電磁波に周
波数変調を加え、前記信号解析手段は検波信号に対して
周波数解析を行うことにより異常検出を行うことを要旨
とする。この構成により、管渠内に入射させる電磁波の
変調方式を周波数変調としたとき、反射電磁波を検波す
ることで送信電磁波と受信電磁波の周波数差が得られ、
この周波数差から電磁波が送信されてから被検査物で反
射されて受信されるまでの時間が求められる。この時間
に電磁波速度を乗じて２で割ることにより被検査物まで
の距離、即ち管渠内の異物又は敷設異常等の異常発生位
置を特定することが可能となる。According to a third aspect of the present invention, there is provided the sewer inspection apparatus according to the second aspect, wherein the modulating means is a frequency control means, and applies frequency modulation to an electromagnetic wave transmitted into the sewer. The gist of the invention is that the signal analysis means performs an abnormality detection by performing a frequency analysis on the detected signal. With this configuration, when the modulation method of the electromagnetic wave to be incident into the sewer is frequency modulation, the frequency difference between the transmitted electromagnetic wave and the received electromagnetic wave is obtained by detecting the reflected electromagnetic wave,
From this frequency difference, the time from when the electromagnetic wave is transmitted to when it is reflected by the inspection object and received is obtained. By multiplying this time by the electromagnetic wave velocity and dividing by two, it is possible to specify the distance to the inspection object, that is, the position where an abnormality such as a foreign matter in the sewer or an abnormal installation is found.
【００１６】請求項４記載の管渠検査装置は、上記請求
項２記載の管渠検査装置において、前記変調手段は、ス
イッチ手段であり、前記管渠内に送信する電磁波として
振幅変調を加えたパルス波を用い、前記信号解析手段は
検波信号を時間解析することにより異常検出を行うこと
を要旨とする。この構成により、電磁波の変調方式を振
幅変調として管渠内にパルス波を入射させたとき、送信
パルス波が発生してから受信パルス波が観測されるまで
の時間を測定し、この時間に電磁波速度を乗じて２で割
ることにより被検査物までの距離、即ち管渠内の異物又
は敷設異常等の異常発生位置を特定することが可能とな
る。According to a fourth aspect of the present invention, there is provided the sewer inspection apparatus according to the second aspect, wherein the modulating means is a switch means, and amplitude modulation is applied as an electromagnetic wave to be transmitted into the sewer. The gist is that the signal analysis means performs an abnormality detection by performing a time analysis of the detection signal using a pulse wave. With this configuration, when a pulse wave is incident on a sewer with the modulation method of the electromagnetic wave as amplitude modulation, the time from the generation of the transmission pulse wave to the observation of the reception pulse wave is measured. By multiplying by the speed and dividing by 2, it is possible to specify the distance to the object to be inspected, that is, the position where an abnormality such as a foreign substance in the sewer or a laying abnormality occurs.
【００１７】請求項５記載の管渠検査装置は、上記請求
項２記載の管渠検査装置において、前記高周波発生手段
を前記送信手段の近傍に配置するか、前記検波手段を前
記受信手段の近傍に配置するか、又は前記高周波発生手
段を前記送信手段の近傍に配置するとともに前記検波手
段を前記受信手段の近傍に配置するかの少なくとも何れ
かの構成としてなることを要旨とする。この構成によ
り、高周波発生手段と送信手段間、又は受信手段と検波
手段間の高周波の流れる伝送線が短縮され、高周波にお
ける伝送路での減衰が低減する。また短縮された高周波
伝送路を固定線路で構成することでミリ波帯の電磁波を
適用することも可能となる。According to a fifth aspect of the present invention, there is provided the sewer inspection apparatus according to the second aspect, wherein the high-frequency generating means is disposed near the transmitting means or the detecting means is disposed near the receiving means. Or the high frequency generating means is arranged near the transmitting means and the detecting means is arranged near the receiving means. With this configuration, the transmission line through which the high frequency flows between the high frequency generation means and the transmission means or between the reception means and the detection means is shortened, and the attenuation of the high frequency transmission line is reduced. Further, by forming the shortened high-frequency transmission line with a fixed line, it becomes possible to apply an electromagnetic wave in the millimeter wave band.
【００１８】請求項６記載の管渠検査装置は、上記請求
項２記載の管渠検査装置において、前記送信手段と前記
受信手段は、前記電磁波の送・受信方向を回転軸とする
回転手段に取り付けてなることを要旨とする。この構成
により、方向性を持つ被検査物に対して電磁波の偏波方
向を調節することが可能となり、電磁波の反射が大きく
なる回転角度を見つけることで被検査物がどの方向に置
かれた場合でも検出が可能となる。According to a sixth aspect of the present invention, there is provided the sewer inspection apparatus according to the second aspect, wherein the transmitting means and the receiving means include a rotating means having a transmitting / receiving direction of the electromagnetic wave as a rotation axis. The gist is to be attached. With this configuration, it is possible to adjust the polarization direction of the electromagnetic wave with respect to the test object having directionality, and in which direction the test object is placed by finding the rotation angle at which the reflection of the electromagnetic wave increases But detection is possible.
【００１９】請求項７記載の管渠検査装置は、上記請求
項６記載の管渠検査装置において、前記回転手段は回転
角制御機能付き回転手段であり、この回転角制御機能付
き回転手段による前記送信手段及び受信手段の回転角度
の制御時に受信強度の最大点を検出する受信強度測定手
段を設けてなることを要旨とする。この構成により、検
査時に送・受信手段の回転角を受信強度に応じて自動制
御することが可能となり、方向性を持つ被検査物を自動
的に検出することが可能となる。According to a seventh aspect of the present invention, there is provided the sewer inspection apparatus according to the sixth aspect, wherein the rotating means is a rotating means having a rotation angle control function. The gist of the invention is to provide a reception intensity measuring unit for detecting a maximum point of the reception intensity when controlling the rotation angles of the transmission unit and the reception unit. With this configuration, it is possible to automatically control the rotation angle of the transmission / reception means at the time of inspection according to the reception intensity, and it is possible to automatically detect an object to be inspected having directivity.
【００２０】[0020]
【発明の実施の形態】以下、本発明の実施の形態を図面
に基づいて説明する。Embodiments of the present invention will be described below with reference to the drawings.
【００２１】図１は、本発明の第１の実施の形態を示す
図である。本実施の形態では、測定対象管渠１の検査に
用いる電磁波発生装置として測定対象管渠１を導波管と
見なした場合の遮断周波数に対して１０倍以上の周波数
を持つ電磁波を発生する高周波発生手段２を用いてい
る。これをアンテナ等の電磁波送信手段３により測定対
象管渠１に対して電磁波を送信し、管渠内反射物（被検
査物）４により反射されて戻ってくる反射波を電磁波受
信手段５で受信する。受信された受信信号は信号解析手
段６によって解析され、出力手段７により出力されるよ
うになっている。出力手段７としては、コンピュータ等
のディスプレイや液晶表示等の表示手段が主に用いられ
るが、表示を行う代わりに外部と検査情報のやりとりを
行う通信手段を用いてもよい。FIG. 1 is a diagram showing a first embodiment of the present invention. In the present embodiment, an electromagnetic wave having a frequency that is 10 times or more as high as a cutoff frequency when the measurement target sewer 1 is regarded as a waveguide is used as an electromagnetic wave generator used for inspection of the measurement target sewer 1. High frequency generating means 2 is used. The electromagnetic wave is transmitted to the measurement target sewer 1 by an electromagnetic wave transmitting means 3 such as an antenna, and the reflected wave reflected by the reflected object (inspection object) 4 in the sewer and returned is received by the electromagnetic wave receiving means 5. I do. The received signal is analyzed by the signal analyzing means 6 and output by the output means 7. As the output means 7, a display such as a computer or a liquid crystal display is mainly used, but a communication means for exchanging inspection information with the outside instead of displaying the information may be used.
【００２２】本実施の形態によれば、電磁波の周波数を
測定対象管渠１を導波管と見なした場合の遮断周波数に
対して１０倍以上としたことにより、測定対象管渠１内
に入射された電磁波は殆どが減衰することなく遠方まで
伝搬する。そして遠方の被検査物４に反射された反射波
を受信することができるため、長距離の管渠を一度に検
査することができる。管渠特にヒューム管を測定対象と
した場合、管渠を導波管と見なした場合の遮断周波数に
対して１０倍以下の周波数を持つ電磁波は管渠内で急速
に減衰し、遠方まで伝搬することができない。According to the present embodiment, the frequency of the electromagnetic wave is set to be at least 10 times the cutoff frequency when the culvert 1 to be measured is regarded as a waveguide. Most of the incident electromagnetic wave propagates far away without being attenuated. Since a reflected wave reflected by the distant inspection object 4 can be received, a long distance sewer can be inspected at a time. When measuring sewers, especially fume pipes, electromagnetic waves having a frequency less than 10 times the cut-off frequency when the sewer is regarded as a waveguide are rapidly attenuated in the sewer and propagate far away. Can not do it.
【００２３】図２には、本発明の第２の実施の形態を示
す。本実施の形態では、高周波発生手段２に変調手段８
を設け、測定時は電磁波に対し時間的に振幅又は周波数
変調を加え、電磁波送信手段３により測定対象管渠１内
に送信する。送信された電磁波は測定対象管渠１内を伝
搬する途中に異物や敷設異常等の被検査物４がある場合
は反射を受ける。反射波は測定対象管渠１内を戻り電磁
波受信手段５により受信されて受信信号となる。受信信
号は検波手段９で検波されて検波信号となった後、信号
解析手段６により解析され、その結果が出力手段７によ
り出力される。本実施の形態では電磁波に振幅変調又は
周波数変調を加えたことにより、検波信号には反射波が
反射された被検査物４の位置情報が含まれている。信号
解析手段６はこの性質を利用して検波信号を解析し、被
検査物４までの距離を求めることができる。これによ
り、管渠異常が発生している位置を特定することが可能
となる。FIG. 2 shows a second embodiment of the present invention. In this embodiment, the modulating means 8
In the measurement, the electromagnetic wave is temporally subjected to amplitude or frequency modulation, and is transmitted by the electromagnetic wave transmitting means 3 into the measurement target sewer 1. The transmitted electromagnetic wave is reflected when there is an inspection object 4 such as a foreign substance or an abnormal installation in the course of propagating in the measurement target sewer 1. The reflected wave returns inside the measuring pipe 1 and is received by the electromagnetic wave receiving means 5 to become a received signal. The received signal is detected by the detection means 9 to become a detection signal, which is then analyzed by the signal analysis means 6, and the result is output by the output means 7. In the present embodiment, the amplitude modulation or the frequency modulation is applied to the electromagnetic wave, so that the detection signal includes the position information of the inspection object 4 where the reflected wave is reflected. The signal analyzing means 6 can analyze the detection signal by utilizing this property and determine the distance to the object 4 to be inspected. This makes it possible to specify the position where the sewer abnormality has occurred.
【００２４】なお、図２では、電磁波送信手段３と電磁
波受信手段５を個別に設けているが、方向性結合器を用
いることにより両者を同一手段で行うことができる。図
３にその構成の一例を示す。電磁波送信と電磁波受信は
単一の電磁波送・受信手段２１で行い、送・受信信号は
方向性結合器の一種であるサーキュレータ２２により分
離され、高周波発生手段２で発生した送信電磁波はサー
キュレータ２２を通った後、電磁波送・受信手段２１へ
と進み測定対象管渠１内に送信される。被検査物４で反
射した反射電磁波は電磁波送・受信手段２１からサーキ
ュレータ２２を通り検波手段９へと進む。本構成によ
り、図２の構成と同様の作用、効果を得ながら、さらに
電磁波送・受信手段２１である送・受信アンテナを同一
のものとすることができる。このため、装置を小型化
し、またアンテナを１個減らすことができるため安価に
構成することができる。また、図３では方向性結合器と
してサーキュレータ２２を用いているが、方向性結合作
用を持つものであれば何でもよく、例えばアイソレータ
を複数個組み合わせたもの等を用いてもよい。In FIG. 2, the electromagnetic wave transmitting means 3 and the electromagnetic wave receiving means 5 are separately provided, but both can be performed by the same means by using a directional coupler. FIG. 3 shows an example of the configuration. Electromagnetic wave transmission and electromagnetic wave reception are performed by a single electromagnetic wave transmission / reception unit 21, transmission / reception signals are separated by a circulator 22 which is a type of directional coupler, and transmission electromagnetic waves generated by the high frequency generation unit 2 are transmitted to the circulator 22. After passing, it proceeds to the electromagnetic wave transmission / reception means 21 and is transmitted into the measurement target sewer 1. The reflected electromagnetic wave reflected by the inspection object 4 travels from the electromagnetic wave transmitting / receiving unit 21 through the circulator 22 to the detecting unit 9. With this configuration, the same operation and effect as the configuration of FIG. 2 can be obtained, and the same transmission / reception antenna as the electromagnetic wave transmission / reception means 21 can be used. Therefore, the device can be reduced in size and the number of antennas can be reduced by one, so that the device can be configured at a low cost. Although the circulator 22 is used as a directional coupler in FIG. 3, any circulator having a directional coupling action may be used. For example, a combination of a plurality of isolators may be used.
【００２５】図４には、本発明の第３の実施の形態を示
す。本実施の形態では、高周波発生手段として周波数制
御機能付き発信器１０を用いている。これは周波数制御
可能なものであればどのような方式であってもよいが、
電圧制御発信器（ＶＣＯ）が最も一般的である。周波数
制御機能付き発信器１０には周波数制御手段１１が取り
付けられており、変調を目的とした周波数制御を行う。
周波数制御機能付き発信器１０にＶＣＯを用いる場合は
周波数制御手段１１として関数電圧発生器を用いればよ
い。送信電磁波と被検査物４で反射された受信電磁波は
検波手段９により検波され、送信電磁波と受信電磁波の
周波数差分が検波信号として取り出される。検波信号は
周波数解析手段１２により周波数解析され、その結果が
出力手段７により出力される。FIG. 4 shows a third embodiment of the present invention. In the present embodiment, the transmitter 10 with a frequency control function is used as the high frequency generating means. This may be any method that can control the frequency,
Voltage controlled oscillators (VCOs) are the most common. A frequency control means 11 is attached to the transmitter 10 having a frequency control function, and performs frequency control for modulation.
When a VCO is used for the transmitter 10 with a frequency control function, a function voltage generator may be used as the frequency control means 11. The transmitting electromagnetic wave and the receiving electromagnetic wave reflected by the inspection object 4 are detected by the detecting means 9, and the frequency difference between the transmitting electromagnetic wave and the receiving electromagnetic wave is extracted as a detection signal. The detected signal is subjected to frequency analysis by the frequency analysis means 12, and the result is output by the output means 7.
【００２６】本実施の形態では、送信電磁波に対して周
波数変調を行っているため、受信電磁波の周波数は送信
電磁波の周波数と変調分だけ異なる。ここで、周波数を
時間に対して単調増加又は単調減衰させるように周波数
変調している場合、送信電磁波と受信電磁波の周波数差
が大きいほど管渠内反射物までの距離が遠いことがわか
る。特に周波数の時間変化が一定である場合には送信電
磁波と受信電磁波の周波数差と管渠内反射物までの距離
は比例するため、距離の測定を行うことが可能となる。
そのため送信電磁波と受信電磁波の周波数差を測定すれ
ば電磁波が管内異物等の被検査物４により反射され受信
されるまでの時間を求めることができ、この時間に電磁
波速度を乗じて２で割れば、反射物までの距離を算出す
ることができる。In this embodiment, since the transmission electromagnetic wave is frequency-modulated, the frequency of the reception electromagnetic wave differs from the frequency of the transmission electromagnetic wave by the amount of modulation. Here, in the case where the frequency is modulated so that the frequency is monotonically increased or attenuated with respect to time, it can be understood that the greater the frequency difference between the transmitted electromagnetic wave and the received electromagnetic wave, the longer the distance to the reflector in the sewer. In particular, when the time change of the frequency is constant, the frequency difference between the transmitted electromagnetic wave and the received electromagnetic wave is proportional to the distance to the reflection object in the sewer, so that the distance can be measured.
Therefore, if the frequency difference between the transmitted electromagnetic wave and the received electromagnetic wave is measured, the time until the electromagnetic wave is reflected and received by the inspection object 4 such as a foreign substance in the pipe can be obtained, and this time is multiplied by the electromagnetic wave speed and divided by 2. And the distance to the reflecting object can be calculated.
【００２７】本実施の形態における検波手段９の詳細に
ついて説明を加える。本実施の形態では周波数差を求め
るため送信電磁波と受信電磁波を直接、検波手段９に加
える。この場合の検波手段９としては通常ミキサと呼ば
れる素子が用いられ、送信電磁波と受信電磁波の積が求
められる。周波数の異なる２成分を乗じると２つの周波
数の和成分と差成分が得られるが、本実施の形態で必要
なのは差成分であるため検波手段９に低周波透過フィル
タを用いて周波数の高い和成分を除去する。こうして得
られた検波信号を周波数解析手段１２により周波数解析
し、検波信号の周波数及びその強度を求める。ここで、
検波信号の周波数は送信電磁波と受信電磁波の周波数差
であり、この周波数差から電磁波が送信されてから管内
の被検査物４で反射されて受信されるまでの時間を求め
ることができ、これに電磁波速度を乗じて２で割ること
により被検査物４までの距離を求めることができる。ま
た、検波信号の強度は管内の被検査物４からの反射強度
に比例するため、検波信号強度から被検査物４の大きさ
や向き、材質などを推定することができる。The details of the detection means 9 in this embodiment will be described. In the present embodiment, the transmission electromagnetic wave and the reception electromagnetic wave are directly applied to the detection means 9 to obtain the frequency difference. In this case, an element usually called a mixer is used as the detection means 9, and the product of the transmission electromagnetic wave and the reception electromagnetic wave is obtained. When the two components having different frequencies are multiplied, a sum component and a difference component of the two frequencies can be obtained. However, since the difference component is required in the present embodiment, a sum component having a high frequency can be obtained by using a low-frequency transmission filter for the detecting means 9. Is removed. The detection signal thus obtained is subjected to frequency analysis by the frequency analysis means 12 to determine the frequency of the detection signal and its intensity. here,
The frequency of the detection signal is the frequency difference between the transmitted electromagnetic wave and the received electromagnetic wave, and from this frequency difference, the time from when the electromagnetic wave is transmitted to when it is reflected by the inspection object 4 in the tube and received can be obtained. By multiplying by the electromagnetic wave velocity and dividing by 2, the distance to the inspection object 4 can be obtained. Further, since the intensity of the detection signal is proportional to the reflection intensity from the inspection object 4 in the tube, the size, direction, material, and the like of the inspection object 4 can be estimated from the detection signal intensity.
【００２８】図５には、本発明の第４の実施の形態を示
す。本実施の形態では、高周波発生手段２にスイッチ手
段１３を設けることにより振幅変調を行い、測定対象管
渠１内にパネル波を送信する構成をとっている。送信電
磁波と受信電磁波は各検波手段９により検波された後、
時間計測手段１４により比較される。時間計測手段１４
では送信パルスが発生してから被検査物４で反射された
受信パルスが発生するまでの時間を計測する。送信電磁
波をパルス波としたことにより、電磁波はパルスが発生
している間だけ伝搬し、管内異物等の被検査物４により
反射された後、測定対象管渠１内を戻り受信される。送
信パルスが発生してから受信パルスが観測されるまでの
時間は電磁波が測定対象管渠１内を往復する時間そのも
のであり、これに電磁波速度を乗じて２で割ることによ
り被検査物４までの距離を求めることができる。また受
信パルスの強度は被検査物４による反射強度に比例す
る。よって時間計測手段１４に受信波の振幅測定機能を
持たせることにより被検査物４の反射強度を測定し、反
射物となっている管内異常の程度を知ることができる。FIG. 5 shows a fourth embodiment of the present invention. In the present embodiment, a configuration is adopted in which amplitude modulation is performed by providing switch means 13 in high-frequency generation means 2 and a panel wave is transmitted into culvert 1 to be measured. After the transmission electromagnetic wave and the reception electromagnetic wave are detected by each detection means 9,
The time is compared by the time measurement unit 14. Time measuring means 14
Then, the time from the generation of the transmission pulse to the generation of the reception pulse reflected by the object 4 is measured. Since the transmission electromagnetic wave is a pulse wave, the electromagnetic wave propagates only while the pulse is being generated, is reflected by the inspection object 4 such as a foreign substance in the pipe, and then returns inside the measurement target culvert 1 to be received. The time from the generation of a transmission pulse to the observation of a reception pulse is the time required for the electromagnetic wave to reciprocate in the measurement target sewer 1 and is multiplied by the electromagnetic wave velocity and divided by 2 to the test object 4. Can be obtained. The intensity of the received pulse is proportional to the intensity of the reflection from the object 4. Therefore, by providing the time measuring means 14 with the function of measuring the amplitude of the received wave, the reflection intensity of the inspection object 4 can be measured, and the degree of an abnormality in the tube serving as the reflection object can be known.
【００２９】図６には、本発明の第５の実施の形態を示
す。本実施の形態では、高周波発生手段２を電磁波送信
手段３の近傍に配置するか、検波手段９を電磁波受信手
段５の近傍に配置するか、又は高周波発生手段２を電磁
波送信手段３の近傍に配置するとともに検波手段９を電
磁波受信手段５の近傍に配置するかの少なくとも何れか
の構成として一体化し、高周波ユニット１５を構成して
いる。検査時は、この高周波ユニット１５を管内に挿入
し、測定実施時には高周波ユニット１５に制御信号を与
えて検波信号を取り出した後に信号解析手段６を用いて
信号解析を行い、出力手段７により表示を行うようにし
ている。FIG. 6 shows a fifth embodiment of the present invention. In the present embodiment, the high-frequency generating means 2 is arranged near the electromagnetic wave transmitting means 3, the detecting means 9 is arranged near the electromagnetic wave receiving means 5, or the high-frequency generating means 2 is arranged near the electromagnetic wave transmitting means 3. The high-frequency unit 15 is configured by integrating the detection means 9 and / or the detection means 9 in the vicinity of the electromagnetic wave reception means 5. At the time of inspection, the high-frequency unit 15 is inserted into a tube. At the time of measurement, a control signal is given to the high-frequency unit 15 to extract a detection signal, and then the signal is analyzed using the signal analysis means 6. I'm trying to do it.
【００３０】本実施の形態では、高周波ユニット１５に
加える制御信号と、受信電磁波を検波して得られる検波
信号は送信電磁波よりも十分低い低周波とすることがで
きるため、制御信号と検波信号の伝送に用いる線路は低
周波用電線を用いることができる。一方、高周波発生手
段２と電磁波送信手段３間、又は電磁波受信手段５と検
波手段９間の高周波の流れる伝送線は短縮され、従来の
ように高周波伝送線を引き回すことがなくなる。この結
果、高周波における伝送路での減衰を低減することが可
能となる。また従来はミリ波帯での実現が困難であった
が、本実施の形態であれば高周波伝送路をユニット内の
固定線路で構成することができるため容易に実現するこ
とができる。In this embodiment, the control signal applied to the high-frequency unit 15 and the detection signal obtained by detecting the reception electromagnetic wave can be set to a sufficiently low frequency lower than the transmission electromagnetic wave. As a transmission line, a low-frequency electric wire can be used. On the other hand, the transmission line through which the high frequency flows between the high frequency generation means 2 and the electromagnetic wave transmission means 3 or between the electromagnetic wave reception means 5 and the detection means 9 is shortened, and the high frequency transmission line is not routed as in the related art. As a result, it is possible to reduce attenuation in a transmission line at a high frequency. Conventionally, it has been difficult to realize the high-frequency transmission line in the millimeter wave band. However, in the present embodiment, the high-frequency transmission line can be easily realized because the high-frequency transmission line can be configured by a fixed line in the unit.
【００３１】なお、本実施の形態では送信部と受信部を
全て一体化しているが、高周波発生手段２又は検波手段
９の何れか一方に何らかの制約がある場合は片方だけを
一体化する場合も考えられる。例えば、高い出力を有す
る電磁波を用いれば、より遠方の反射物検出を行った
り、またより微小な反射物の検出を行うことが可能とな
る。しかし高出力の高周波発生手段は大概大型であり、
アンテナ等の送信手段と一体化することが困難となるこ
とが考えられる。この場合は、受信部のみを一体化する
方式が実用的と考えられる。送信部を延長することによ
り減衰を生じるが、これは高周波発生手段の出力を予め
高く設定しておけばよい。In the present embodiment, the transmitting section and the receiving section are all integrated. However, if there is some restriction on either the high-frequency generating means 2 or the detecting means 9, only one of them may be integrated. Conceivable. For example, if an electromagnetic wave having a high output is used, it is possible to detect a farther-reflecting object or to detect a finer reflecting object. However, high-power high-frequency generators are generally large,
It may be difficult to integrate with a transmitting means such as an antenna. In this case, a system in which only the receiving unit is integrated is considered to be practical. Attenuation is caused by extending the transmission unit. This can be achieved by setting the output of the high-frequency generation means to be high in advance.
【００３２】図７には、本発明の第６の実施の形態を示
す。本実施の形態では、電磁波送信手段３、電磁波受信
手段５を回転手段１６に取り付け、電磁波の送・受信方
向を軸として回転できるようにしてある。測定を行う
際、被検査物４に方向性がある場合は電磁波の偏波方向
と被検査物４の向きの違いにより反射が得られにくくな
る場合がある。管内の被検査物４がどちらを向いている
かは当然ながら不明であるから、たまたま電磁波の偏波
方向と被検査物４の向きが反射が小さくなる関係であっ
た場合にはかなり大きな被検査物４であっても検出でき
ない可能性がある。そこで、測定中、受信信号が小さい
と考えられる場合は電磁波送・受信手段３，５を回転さ
せる。もし上記のように、たまたま電磁波の偏波方向と
被検査物４の向きが反射が小さくなる関係であった場
合、電磁波送・受信手段３，５の回転により電磁波の偏
波角度が変化し、電磁波の偏波方向と被検査物４の向き
が揃えば反射強度が増加する。この結果、方向性を持つ
被検査物４を確実に検出することができる。FIG. 7 shows a sixth embodiment of the present invention. In the present embodiment, the electromagnetic wave transmitting means 3 and the electromagnetic wave receiving means 5 are attached to the rotating means 16 so that the electromagnetic wave transmitting means 3 and the electromagnetic wave receiving means 5 can be rotated about the transmission / reception direction of the electromagnetic wave. When the measurement is performed, if the test object 4 has directionality, it may be difficult to obtain reflection due to a difference between the polarization direction of the electromagnetic wave and the direction of the test object 4. It is of course unknown which direction the test object 4 in the tube faces, so if the incident direction of the electromagnetic wave and the direction of the test object 4 happen to have a relationship in which the reflection becomes small, the test object 4 is considerably large. There is a possibility that even 4 is not detected. Therefore, if the received signal is considered to be small during the measurement, the electromagnetic wave transmitting / receiving means 3 and 5 are rotated. If, as described above, the direction of polarization of the electromagnetic wave and the direction of the inspection object 4 happen to be in a relationship in which the reflection is small, the polarization angle of the electromagnetic wave changes due to the rotation of the electromagnetic wave transmitting / receiving means 3 and 5, If the polarization direction of the electromagnetic wave is aligned with the direction of the inspection object 4, the reflection intensity increases. As a result, it is possible to reliably detect the inspection object 4 having directionality.
【００３３】図８には、本発明の第７の実施の形態を示
す。本実施の形態では、電磁波送信手段３、電磁波受信
手段５を制御機能付き回転手段１７に取り付け、電磁波
の送・受信方向を軸として回転角度を制御できるように
してある。また受信強度測定手段１８により受信信号の
強度を測定する。この受信強度測定手段１８は単独で持
つ必要はなく、第１〜第６の実施の形態における信号解
析手段の中や検波手段の中で実現させてもよい。さらに
回転角度制御手段１９が受信強度測定手段１８が測定し
た受信強度が最大となるように電磁波送・受信手段３，
５の回転角度を自動的に制御する。FIG. 8 shows a seventh embodiment of the present invention. In the present embodiment, the electromagnetic wave transmitting means 3 and the electromagnetic wave receiving means 5 are attached to the rotating means 17 with a control function so that the rotation angle can be controlled with the transmission / reception direction of the electromagnetic wave as an axis. The received signal strength is measured by the received signal strength measuring means 18. The reception intensity measuring means 18 does not need to be provided independently, and may be realized in the signal analyzing means or the detecting means in the first to sixth embodiments. Further, the electromagnetic wave transmission / reception means 3 and the rotation angle control means 19 are controlled so that the reception intensity measured by the reception intensity measurement means 18 is maximized.
5 is automatically controlled.
【００３４】本実施の形態では、電磁波送・受信手段
３，５の向き並びに電磁波の偏波方向は被検査物４の向
きに対して反射が最大となる角度に制御される。このた
め測定中人力で電磁波送・受信手段３，５を回転する必
要がなくなり、方向性を持つ被検査物４の検出を確実に
するとともに省力化の効果がある。In this embodiment, the directions of the electromagnetic wave transmitting / receiving means 3 and 5 and the direction of polarization of the electromagnetic wave are controlled to an angle at which the reflection becomes maximum with respect to the direction of the inspection object 4. Therefore, there is no need to manually rotate the electromagnetic wave transmitting / receiving means 3 and 5 during the measurement, so that it is possible to reliably detect the inspection object 4 having directivity and to save labor.
【００３５】[0035]
【発明の効果】以上説明したように、請求項１記載の管
渠検査方法によれば、電磁波の周波数を、管渠を導波管
と見なした場合の遮断周波数に対して１０倍以上とした
ため、管渠内に入射した電磁波は殆ど減衰することなく
遠方まで伝搬し、遠方の被検査物で反射した電磁波を受
信することができて、長距離の管渠でも一度で検査する
ことができる。As described above, according to the pipe inspection method of the first aspect, the frequency of the electromagnetic wave is at least 10 times the cutoff frequency when the pipe is regarded as a waveguide. Therefore, the electromagnetic wave incident into the sewer propagates to the distant place with almost no attenuation, and the electromagnetic wave reflected by the distant inspection object can be received, so that even a long distance sewer can be inspected at one time. .
【００３６】請求項２記載の管渠検査装置によれば、電
磁波を用いて上下水等の管渠に生じた異常を検出する管
渠検査装置において、前記管渠を導波管と見なした場合
の遮断周波数に対し１０倍以上の周波数を持つ電磁波を
発生する高周波発生手段と、この高周波発生手段で発生
した電磁波に変調情報を加える変調手段と、前記管渠内
に前記変調情報を加えた電磁波を送信する送信手段と、
前記管渠内の異物又は敷設異常等により反射された電磁
波を受信する受信手段と、この受信手段の受信信号を検
波して検波信号とする検波手段と、前記検波信号に対し
送信電磁波に与えた前記変調情報を基に信号解析を行う
ことにより異常検出を行う信号解析手段とを具備させた
ため、反射電磁波を検波した検波信号には被検査物まで
の距離を反映した情報が含まれるので、この検波信号を
信号解析することで、長距離の管渠でも被検査物までの
距離、即ち管渠内の異物又は敷設異常等の異常発生位置
を特定することができる。According to a second aspect of the present invention, in a culvert inspection apparatus for detecting an abnormality generated in a culvert such as water and sewage using electromagnetic waves, the culvert is regarded as a waveguide. A high frequency generating means for generating an electromagnetic wave having a frequency ten times or more higher than a cutoff frequency in the case; a modulating means for adding modulation information to the electromagnetic wave generated by the high frequency generating means; and the modulation information being added to the inside of the pipe. Transmitting means for transmitting electromagnetic waves,
A receiving means for receiving an electromagnetic wave reflected by a foreign substance or a laying abnormality in the sewer, a detecting means for detecting a reception signal of the receiving means to make a detection signal, and applying the detection signal to a transmission electromagnetic wave. Since signal analysis means for performing abnormality detection by performing signal analysis based on the modulation information is provided, the detection signal obtained by detecting the reflected electromagnetic wave includes information reflecting the distance to the inspection object. By performing signal analysis on the detection signal, it is possible to specify the distance to the object to be inspected, that is, the position where an abnormality such as a foreign substance or a laying abnormality occurs in the conduit, even in a long distance conduit.
【００３７】請求項３記載の管渠検査装置によれば、前
記変調手段は、周波数制御手段であり、前記管渠内に送
信する電磁波に周波数変調を加え、前記信号解析手段は
検波信号に対して周波数解析を行うことにより異常検出
を行うようにしたため、反射電磁波を検波した検波信号
には、電磁波が送信されてから被検査物で反射されて受
信されるまでの時間を反映した情報が含まれるので、こ
の検波信号を周波数解析することで、長距離の管渠でも
被検査物までの距離、即ち管渠内の異物又は敷設異常等
の異常発生位置を特定することができる。According to a third aspect of the present invention, the modulating means is a frequency control means, which applies frequency modulation to an electromagnetic wave transmitted into the sewer, and the signal analyzing means applies a modulation to the detected signal. In order to detect abnormalities by performing frequency analysis, the detection signal that detects the reflected electromagnetic wave contains information that reflects the time from when the electromagnetic wave is transmitted to when it is reflected by the object and received. Therefore, by analyzing the frequency of the detected signal, it is possible to specify the distance to the object to be inspected, that is, the position where an abnormality such as a foreign matter in the sewer or a laying abnormality occurs even in a long sewer.
【００３８】請求項４記載の管渠検査装置によれば、前
記変調手段は、スイッチ手段であり、前記管渠内に送信
する電磁波として振幅変調を加えたパルス波を用い、前
記信号解析手段は検波信号を時間解析することにより異
常検出を行うようにしたため、反射電磁波を検波した検
波信号には、送信パルス波が発生してから被検査物で反
射された受信パルス波が観測されるまでの時間を反映し
た情報が含まれるので、この検波信号を時間解析するこ
とで、長距離の管渠でも被検査物までの距離、即ち管渠
内の異物又は敷設異常等の異常発生位置を特定すること
ができる。According to a fourth aspect of the present invention, the modulating means is a switch means, and a pulse wave subjected to amplitude modulation is used as an electromagnetic wave to be transmitted into the sewer, and the signal analyzing means is provided. Abnormality detection is performed by time analysis of the detection signal, so the detection signal that detects the reflected electromagnetic wave is generated from the time when the transmission pulse wave is generated until the time when the reception pulse wave reflected by the object is observed. Since information reflecting the time is included, the detected signal is analyzed with time to determine the distance to the object to be inspected even in a long-distance pipe, that is, an abnormality occurrence position such as a foreign substance in the pipe or a laying abnormality. be able to.
【００３９】請求項５記載の管渠検査装置によれば、前
記高周波発生手段を前記送信手段の近傍に配置するか、
前記検波手段を前記受信手段の近傍に配置するか、又は
前記高周波発生手段を前記送信手段の近傍に配置すると
ともに前記検波手段を前記受信手段の近傍に配置するか
の少なくとも何れかの構成としたため、高周波の流れる
伝送線が短縮されて、電磁波の周波数を、管渠を導波管
と見なした場合の遮断周波数に対し１０倍以上として
も、伝送路での減衰を低減させることができる。請求項
６記載の管渠検査装置によれば、前記送信手段と前記受
信手段は、前記電磁波の送・受信方向を回転軸とする回
転手段を取り付けたため、方向性を持つ被検査物に対し
電磁波の偏波方向を調節することができて、長距離の管
渠内で方向性を持つ被検査物がどの方向に置かれた場合
でも確実に検出することができる。According to the duct inspection apparatus of the fifth aspect, the high-frequency generating means is arranged near the transmitting means,
Because the detecting means is arranged in the vicinity of the receiving means, or the high-frequency generating means is arranged in the vicinity of the transmitting means and the detecting means is arranged in the vicinity of the receiving means. Even if the transmission line through which the high frequency flows is shortened, the attenuation of the transmission line can be reduced even if the frequency of the electromagnetic wave is 10 times or more the cutoff frequency when the conduit is regarded as a waveguide. According to the sewer inspection apparatus of claim 6, the transmitting means and the receiving means are provided with a rotating means having a transmitting / receiving direction of the electromagnetic wave as a rotation axis. Can be adjusted, and it is possible to reliably detect an object having directivity placed in any direction in a long-length sewer.
【００４０】請求項７記載の管渠検査装置によれば、前
記回転手段は回転角制御機能付き回転手段であり、この
回転角制御機能付き回転手段による前記送信手段及び受
信手段の回転角度の制御時に受信強度の最大点を検出す
る受信強度測定手段を設けたため、検査時に送・受信手
段の回転角を受信強度に応じて自動制御することができ
て、長距離の管渠でも方向性を持つ被検査物を確実かつ
自動的に検出することができる。According to a seventh aspect of the present invention, the rotating means is a rotating means having a rotation angle control function, and the rotating means having the rotation angle control function controls the rotation angles of the transmitting means and the receiving means. Sometimes the receiving intensity measuring means to detect the maximum point of the receiving intensity is provided, so that the rotation angle of the sending and receiving means can be automatically controlled according to the receiving intensity at the time of inspection, and it has directionality even for long distance pipes The inspection object can be detected reliably and automatically.
【図１】本発明の第１の実施の形態である管渠検査装置
のブロック図である。FIG. 1 is a block diagram of a sewer inspection apparatus according to a first embodiment of the present invention.
【図２】本発明の第２の実施の形態のブロック図であ
る。FIG. 2 is a block diagram of a second embodiment of the present invention.
【図３】上記第２の実施の形態の変形例を示すブロック
図である。FIG. 3 is a block diagram showing a modification of the second embodiment.
【図４】本発明の第３の実施の形態のブロック図であ
る。FIG. 4 is a block diagram of a third embodiment of the present invention.
【図５】本発明の第４の実施の形態のブロック図であ
る。FIG. 5 is a block diagram of a fourth embodiment of the present invention.
【図６】本発明の第５の実施の形態のブロック図であ
る。FIG. 6 is a block diagram of a fifth embodiment of the present invention.
【図７】本発明の第６の実施の形態のブロック図であ
る。FIG. 7 is a block diagram of a sixth embodiment of the present invention.
【図８】本発明の第７の実施の形態のブロック図であ
る。FIG. 8 is a block diagram of a seventh embodiment of the present invention.
【図９】従来の管渠検査装置のブロック図である。FIG. 9 is a block diagram of a conventional sewer inspection apparatus.
【図１０】ヒューム管内の電磁波減衰特性を示す特性図
である。FIG. 10 is a characteristic diagram showing electromagnetic wave attenuation characteristics in a fume tube.
１ 測定対象管渠 ２ 高周波発生手段 ３ 電磁波送信手段 ４ 管渠内反射物（被検査物） ５ 電磁波受信手段 ６ 信号解析手段 ８ 変調手段 ９ 検波手段 １０ 周波数制御機能付き発信器 １２ 周波数解析手段 １３ スイッチ手段 １４ 時間計測手段 １６ 回転手段 １７ 制御機能付き回転手段 １８ 受信強度測定手段 １９ 回転角度制御手段 DESCRIPTION OF SYMBOLS 1 Measurement target sewer 2 High frequency generation means 3 Electromagnetic wave transmission means 4 Reflection object in a sewer (test object) 5 Electromagnetic wave reception means 6 Signal analysis means 8 Modulation means 9 Detection means 10 Transmitter with frequency control function 12 Frequency analysis means 13 Switch means 14 Time measurement means 16 Rotation means 17 Rotation means with control function 18 Reception intensity measurement means 19 Rotation angle control means
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ テーマコート゛(参考） Ｇ０１Ｎ 22/00 Ｇ０１Ｎ 22/00 Ｓ ──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. 7 Identification symbol FI Theme coat ゛ (Reference) G01N 22/00 G01N 22/00 S
Claims (7)
異常を検出する管渠検査方法において、前記電磁波の周
波数を、前記管渠を導波管と見なした場合の遮断周波数
に対して１０倍以上としたことを特徴とする管渠検査方
法。1. A sewer inspection method for detecting an abnormality in a sewer such as water supply and sewerage using an electromagnetic wave, wherein the frequency of the electromagnetic wave is set to a cutoff frequency when the sewer is regarded as a waveguide. A sewer inspection method characterized in that the number is 10 times or more.
異常を検出する管渠検査装置において、前記管渠を導波
管と見なした場合の遮断周波数に対し１０倍以上の周波
数を持つ電磁波を発生する高周波発生手段と、この高周
波発生手段で発生した電磁波に変調情報を加える変調手
段と、前記管渠内に前記変調情報を加えた電磁波を送信
する送信手段と、前記管渠内の異物又は敷設異常等によ
り反射された電磁波を受信する受信手段と、この受信手
段の受信信号を検波して検波信号とする検波手段と、前
記検波信号に対し送信電磁波に与えた前記変調情報を基
に信号解析を行うことにより異常検出を行う信号解析手
段とを有することを特徴とする管渠検査装置。2. A sewer inspection apparatus for detecting an abnormality generated in a sewer such as water supply and sewerage by using an electromagnetic wave. High-frequency generating means for generating an electromagnetic wave having: a modulating means for adding modulation information to the electromagnetic wave generated by the high-frequency generating means; a transmitting means for transmitting the electromagnetic wave with the modulation information added to the inside of the sewer; Receiving means for receiving an electromagnetic wave reflected by a foreign matter or a laying abnormality in the apparatus, a detecting means for detecting a signal received by the receiving means to obtain a detection signal, and the modulation information given to the transmission electromagnetic wave with respect to the detection signal And a signal analyzing means for performing an abnormality detection by performing a signal analysis based on the signal.
り、前記管渠内に送信する電磁波に周波数変調を加え、
前記信号解析手段は検波信号に対して周波数解析を行う
ことにより異常検出を行うことを特徴とする請求項２記
載の管渠検査装置。3. The modulation means is a frequency control means, and applies frequency modulation to an electromagnetic wave transmitted into the sewer,
3. The sewer inspection apparatus according to claim 2, wherein the signal analysis unit detects an abnormality by performing frequency analysis on the detected signal.
前記管渠内に送信する電磁波として振幅変調を加えたパ
ルス波を用い、前記信号解析手段は検波信号を時間解析
することにより異常検出を行うことを特徴とする請求項
２記載の管渠検査装置。4. The modulation means is a switch means,
3. The sewer inspection apparatus according to claim 2, wherein an amplitude-modulated pulse wave is used as the electromagnetic wave to be transmitted into the sewer, and the signal analysis unit detects an abnormality by performing a time analysis on the detection signal. .
傍に配置するか、前記検波手段を前記受信手段の近傍に
配置するか、又は前記高周波発生手段を前記送信手段の
近傍に配置するとともに前記検波手段を前記受信手段の
近傍に配置するかの少なくとも何れかの構成としてなる
ことを特徴とする請求項２記載の管渠検査装置。5. The method according to claim 1, wherein the high-frequency generating means is arranged near the transmitting means, the detecting means is arranged near the receiving means, or the high-frequency generating means is arranged near the transmitting means. 3. The sewer inspection apparatus according to claim 2, wherein at least one of the detection means and the reception means is arranged near the reception means.
磁波の送・受信方向を回転軸とする回転手段に取り付け
てなることを特徴とする請求項２記載の管渠検査装置。6. A sewer inspection apparatus according to claim 2, wherein said transmission means and said reception means are attached to a rotation means having a transmission / reception direction of said electromagnetic wave as a rotation axis.
手段であり、この回転角制御機能付き回転手段による前
記送信手段及び受信手段の回転角度の制御時に受信強度
の最大点を検出する受信強度測定手段を設けてなること
を特徴とする請求項６記載の管渠検査装置。7. The receiving means for detecting a maximum point of the receiving intensity when the rotating means having a rotation angle control function controls the rotation angles of the transmitting means and the receiving means. 7. The sewer inspection apparatus according to claim 6, further comprising a measuring means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000059108A JP2001249085A (en) | 2000-03-03 | 2000-03-03 | Method and apparatus for inspecting sewer pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000059108A JP2001249085A (en) | 2000-03-03 | 2000-03-03 | Method and apparatus for inspecting sewer pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2001249085A true JP2001249085A (en) | 2001-09-14 |
Family
ID=18579607
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2000059108A Pending JP2001249085A (en) | 2000-03-03 | 2000-03-03 | Method and apparatus for inspecting sewer pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2001249085A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008224666A (en) * | 2007-03-08 | 2008-09-25 | Tohoku Univ | Microwave measurement system of piping thickness reduction |
| KR20190040032A (en) * | 2016-08-22 | 2019-04-16 | 바스프 에스이 | And apparatus for detecting sediments in a pipe system of an apparatus |
-
2000
- 2000-03-03 JP JP2000059108A patent/JP2001249085A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008224666A (en) * | 2007-03-08 | 2008-09-25 | Tohoku Univ | Microwave measurement system of piping thickness reduction |
| KR20190040032A (en) * | 2016-08-22 | 2019-04-16 | 바스프 에스이 | And apparatus for detecting sediments in a pipe system of an apparatus |
| JP2019525192A (en) * | 2016-08-22 | 2019-09-05 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Method and apparatus for identifying deposits in a piping system of a mechanism |
| JP7073344B2 (en) | 2016-08-22 | 2022-05-23 | ビーエーエスエフ ソシエタス・ヨーロピア | Methods and equipment for identifying deposits in the mechanism's piping system |
| US11579098B2 (en) | 2016-08-22 | 2023-02-14 | Basf Se | Method and apparatus for detecting deposits in a pipe system of an apparatus |
| KR102536058B1 (en) * | 2016-08-22 | 2023-05-24 | 바스프 에스이 | Method and apparatus for detecting deposits in a pipe system of a device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0745841B1 (en) | A method and apparatus for inspecting a pipe using electromagnetic radiation | |
| US5773984A (en) | Method of inspecting abnormality occurring inside pipe and apparatus for practicing the method | |
| JP2007327883A (en) | Approach detection system | |
| US7852091B2 (en) | Microwave determination of location and speed of an object inside a pipe | |
| Yoshida et al. | Microwave time-domain analysis for non-destructive inspection of FRPM pipelines using electro-optic sensor | |
| EP0629837B1 (en) | Method of measuring inner diameter of pipe | |
| WO1994017373A1 (en) | Procedure for determining material flow rate | |
| JP2001249085A (en) | Method and apparatus for inspecting sewer pipe | |
| KR101670488B1 (en) | System and method for gathering underground facilities information using tube type insertion device | |
| JP3400255B2 (en) | Piping equipment abnormality detection method and abnormality diagnosis device | |
| JP2008224666A (en) | Microwave measurement system of piping thickness reduction | |
| JP2004077475A (en) | Road surface condition determination method and device | |
| JP2019052866A (en) | Tubular body inspection method | |
| JPH10105878A (en) | Traffic signal controller | |
| JPH1010173A (en) | Method and apparatus for evaluating characteristics of antenna | |
| JPH04215046A (en) | Detecting method for internal residue in steel pipe | |
| WO2011131992A1 (en) | An electromagnetic sensor | |
| JPH0634754A (en) | Radar equipment | |
| JPH074941A (en) | Inside-of-tube inspection apparatus | |
| JPH0961377A (en) | Method for inspecting buried metal pipe with electromagnetic wave | |
| JP3132970B2 (en) | Robot position detection device in metal tube | |
| KR101235593B1 (en) | Apparatus for measuring length of a pipe in air conditioning system | |
| GB2137449A (en) | Target detection systems | |
| JPH075123A (en) | Method for inspecting inside of pipe | |
| RU2213292C1 (en) | Method of location of leak and estimation of its size in underwater pipe line |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20050712 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20050912 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20051129 |