JP4159201B2

JP4159201B2 - Water leak detection system

Info

Publication number: JP4159201B2
Application number: JP27526199A
Authority: JP
Inventors: 健荒井
Original assignee: Maeda Corp
Current assignee: Maeda Corp
Priority date: 1999-09-28
Filing date: 1999-09-28
Publication date: 2008-10-01
Anticipated expiration: 2019-09-28
Also published as: JP2001099741A

Description

【０００１】
【発明の属する技術分野】
本発明は、合成樹脂または合成ゴムシートあるいはアスファルトなどの絶縁性遮水膜を敷設して造成された管理型終末処分場等における漏水位置検出システムに関する。
【０００２】
【従来の技術】
従来、遮水膜を用いた人工的な管理型終末処分場においては、漏水が発生すると地下水汚染や公害問題等が発生するため、定期的に遮水膜の点検を行い、遮水膜に破損が生じていれば漏水箇所を検出して適当な補修を行う必要がある。
【０００３】
このような遮水膜の漏水発生位置を検出するために、次のような検出方式が採用されている。この検出方式では、遮水膜の下側に所定の間隔で複数の線状電極を平行に敷設し、遮水膜の上側には下側電極と交差する方向で所定の間隔で複数の線状電極を平行に敷設した電極配置構成を用いる。このような電極配置構成において、遮水膜上下の線状電極を電極セレクタを介して各々１本選択して上下の線状電極間に交流電源による通電を行い、上下の線状電極間に流れる電流を検出して、印加電圧の位相に同期した信号で位相検波を行う、そして、上下の線状電極の各々の交点における位相検波回路の出力電圧の比較から漏水発生位置を検出する。
【０００４】
以下に、この漏水発生位置検出方式の一例を、図３を参照して説明する。この例においては、遮水膜（しゃ水シート）１０の上側に線状電極１〜８が配置され、遮水膜１０の下側に、線状電極１〜８と交差する方向に線状電極Ａ〜Ｈがそれぞれ配置されている。第１の電極セレクタ８４には、上側の線状電極１〜８のうちの１本（図３では線状電極３）を選択すると残りの線状電極は全て共通に接続する機能を持つ電極セレクタが用いられている。第２の電極セレクタ８５も同様である。
【０００５】
発振器８１で作り出された信号波形は電力増幅回路８２で電力増幅される。電力増幅回路８２と上側の線状電極１〜８及び下側の線状電極Ａ〜Ｈとの間は、第１、第２の電極セレクタ８４、８５により、次のように接続される。
【０００６】
まず、下側の線状電極Ａ〜Ｈにおいては、第２の電極セレクタ８５で選択された１本の線状電極Ｃが電力増幅回路８２の出力側（交流電源）の一方に接続され、残りの線状電極Ａ、Ｂ、Ｄ〜Ｈは全て電力増幅回路８２の出力側の他方に直接接続される。
【０００７】
次に、上側の線状電極１〜８においては、電力増幅回路８２の出力側（交流電源）の他方に、第１の電極セレクタ８４で選択された１本の線状電極３が電流検出回路８３を介して接続され、残りの線状電極１、２、４〜８は全て電力増幅回路８２の出力側の他方に直接接続される。
【０００８】
その結果、上側の線状電極３と残りの全ての線状電極との間に電流が流れるが、電流検出回路８３では上側の線状電極３と下側において選択された線状電極Ｃとの間に流れる電流のみが検出される。位相検波回路８６は、電力増幅回路８２から出力される印加電圧に同期した位相で電流検出回路８３の位相検波を行う。この位相検波出力は、例えばＡ／Ｄコンバータでディジタル信号に変換され、パソコンのようなコンピュータ（何れも図示せず）に与えられ、画像表示される。
【０００９】
このような構成において、遮水膜１０に破損が無い場合、遮水膜１０の上下において選択された線状電極３、Ｃ間に流れる電流は遮水膜１０の容量成分を流れる電流となるため、電流の絶対値は小さい値となり、且つ電力増幅回路８２の印加電圧の位相に対しては進み位相となる。一方、遮水膜１０に破損が生じると、破損箇所の上下において選択された線状電極間には電流が流れ易い。このことから、遮水膜１０の上下の線状電極の組合せ交点が破損箇所に近い場合には電流の絶対値は大きくなり、且つ印加電圧の位相に近づく傾向を示す。このことから、上下の線状電極のそれぞれの交点について電流を測定することにより遮水膜１０の破損箇所を検出することが可能になる。
【００１０】
従来の検出方式の電流測定には位相検波回路８６が用いられており、電力増幅回路８２の出力に基づく印加電圧に同期した位相で電流検出回路８３の出力に対する位相検波が行われ交流電源との同期成分を抽出している。
【００１１】
【発明が解決しようとする課題】
ところで、このような漏水発生位置検出方式においては、線状電極に沿ってその周辺での電位分布が全体として一様であり、漏水位置付近の測定対象の電極部分のみ電位が変化している方が測定精度が向上する。即ち、電位が全体として一様であればあるほど、その一様な電位の中での微少な電位の変化も容易に検出可能となるからである。
【００１２】
この点、従来の漏水発生位置検出方式では、このように相互に間隔をおいて遮水膜の上下に複数配置した線状電極だけでは、その線状電極から離れるにしたがい急激に電位が低下するため、遮水膜の表裏で電位差が急激に小さくなる領域が形成され、その領域では測定される電流の大きさも小さくなる欠点がある。測定される電流が小さくとも、電流が精密に計測できれば問題とならないが、微少な漏水を検出する場合には、測定回路では除去しきれないノイズ等に信号が埋もれて検出できないケースも生じる。
【００１３】
この点の解決手段として、遮水膜の上下の線状電極の配置本数を増やし、線状電極相互の間隔を小さくすることが考えられる。しかし、この方法では、線状電極の配置本数を増やすのに比例して必要な設備コスト並びに施工コスト等が増大する新たな問題が生じる。
【００１４】
よって、本発明の課題は、遮水膜の下側の線状電極と交差する線状電極のみを増設する工夫を凝らすことで、必要な設備コストや施工コストを抑制しつつ、電位分布の変化を全体として小さくし、これにより漏水発生位置検出のための測定精度を向上させることができる技術を提供することにある。
【００１５】
【課題を解決するための手段】
本発明の第１の手段は、敷設された遮水膜の上側に平行に所定の間隔で並べられた複数の上側線状電極と、前記遮水膜の下側に平行に前記上側線状電極と交差するように所定の間隔で並べられた複数の下側線状電極と、選択接続手段により選択された上下の線状電極間に流れる電流を検出する電流検出回路と、その電流検出回路の出力から印加電圧の位相と同相の電流を抽出する位相検波回路とを含み、上下の線状電極の各々の交点における位相検波回路の出力電圧の比較から漏水発生位置を検出する漏水位置検出システムにおいて、
前記遮水膜の下側に、前記下側線状電極と交差しかつ上側線状電極と上下方向に重ならないように所定の間隔で並べられた複数の増設線状電極が配置され、それら増設線状電極と前記下側線状電極との交差部分に電気的短絡を防止する絶縁体が配置され、前記下側線状電極は前記選択接続手段を介して交流電源の一方に接続され、増設線状電極を含む残りの線状電極は交流電源の他方に接続されている構成とした。
【００１６】
この第１の手段によれば、遮水膜の下側に、下側線状電極と交差しかつ上側線状電極と上下方向に重ならないように所定の間隔で並べた複数の増設線状電極を配置したことで、下側線状電極に対して上側線状電極と増設線状電極の両方が交差する形態となる。これにより、電極どうしの交差部分が多くなり、その分、全体としての電位分布の変化がより小さくなる。換言すれば、下側線状電極に沿ってその周辺の電位差がより小さくなる。したがって、電位変化に基づく漏水発生位置の検出が容易となり、測定精度が向上する。また、遮水膜の下側にのみ下側線状電極に交差する増設線状電極を複数設けるだけであるため、上下の線状電極数を全体的に増やす対策に比べて設備コスト及び施工コストの上昇を抑制することができる。
【００１７】
本発明の第２の手段においては、各増設線状電極が、互いに平行に延びる上側線状電極相互の中間部分にそれぞれ位置しかつ上側線状電極と平行に配置されている構成とした。このようにすることで、下側線状電極に対して上側線状電極と増設線状電極が交互にかつほぼ等間隔で交差する形態となる。これにより、電位分布の変化をより小さくしかもほぼ一様にすることができ、測定精度をさらに向上させることができる。
【００１８】
本発明の第３の手段においては、絶縁体は、下側線状電極と増設線状電極との交差部分において、少なくとも一方の線状電極を被覆する絶縁被覆により形成されている構成とした。このように絶縁被覆とすることで、絶縁体を位置決めして設けることができる。したがって、電気的短絡防止効果を確実に発揮させることができる他、別部材として絶縁体を配置するよりも施工性が良くなる。
【００１９】
本発明の第４の手段は、遮水膜を敷設して造成された管理型終末処理場において、前記遮水膜の上側に平行に所定の間隔で並べられた複数の上側線状電極と、前記遮水膜の下側に平行に前記上側の線状電極と交差するように所定の間隔で並べられた複数の下側線状電極と、交流電源と、前記複数の上側線状電極の１本を選択すると共に、前記複数の下側線状電極の１本を選択し、選択した下側線状電極のみを交流電源の一方に接続し、他の線状電極はすべて交流電源の他方に接続するための選択接続手段と、交流電源の一方に接続された下側線状電極と、反対側において選択された１本の上側線状電極との間に流れる電流を検出するための電流検出回路と、この電流検出回路の出力を受けて検波を行う検波手段を含み、上側及び下側の複数の線状電極を順次選択して遮水膜の破損による漏水発生位置に近い線状電極の組合せになった際に前記検波手段の出力が他の電極組合せの値よりも上昇又は下降することから漏水発生位置を検出する処理回路と、前記遮水膜の下側に、前記下側線状電極と交差しかつ上側線状電極と上下方向に重ならないように所定の間隔で並べられた複数の増設線状電極と、それら増設線状電極と前記下側線状電極との交差部分にそれぞれ設けられ、各交差部分における電気的短絡を防止するための絶縁体とを備え、前記各増設線状電極は交流電源の他方にそれぞれ接続されている構成とした。
【００２０】
このような構成によれば、交流電源の一方に接続された１本の下側線状電極と交流電源の他方に接続された他のすべての線状電極との間に電流が流れるが、電流測定は遮水膜を介して反対側において選択された１本の上側線状電極だけに対して行われる構成となる。このことから、交流電源の一方に接続された下側状電極と電流測定が行われる反対側の上側線状電極との交差部分付近に限定された電流測定が行われるため、遮水膜の破損を検出する精度は向上する。これに加えてさらに、下側線状電極と交差する複数の増設線状電極を配置していることで、これらの増設線状電極が電場制御作用を発揮し、下側線状電極に沿ってその周辺の電位分布の変化がより小さくなる。したがって、電位変化に基づく漏水発生位置の検出が容易となり、測定精度が格段に向上する。
【００２１】
【発明の実施の形態】
以下、本発明の好適な実施の形態について図面を参照して詳細に説明する。
図１は、本発明の実施の形態の構成を示すブロック図である。従来と同様、遮水膜（しゃ水シート）１０の上に上側線状電極１〜８が配置され、遮水膜１０の下に、上側線状電極１〜８と交差する方向に下側線状電極Ａ〜Ｈがそれぞれ配置されている。
【００２２】
第１の電極セレクタ８４には、上側線状電極１〜８のうちの１本（図１では線状電極３）を選択すると残りの上側線状電極は全て共通に接続する機能を持つ電極セレクタが用いられている。第２の電極セレクタ８５も同様である。
【００２３】
発振器８１で作り出された信号波形は電力増幅回路８２で電力増幅される。電力増幅回路８２と上側線状電極１〜８及び下側線状電極Ａ〜Ｈとの間は、第１、第２の電極セレクタ８４、８５により、次のように接続される。
【００２４】
まず、下側線状電極Ａ〜Ｈにおいては、第２の電極セレクタ８５で選択された１本の線状電極Ｃが電力増幅回路８２の出力側の一方に接続され、残りの線状電極Ａ、Ｂ、Ｄ〜Ｈは全て電力増幅回路８２の出力側の他方に直接接続される。
【００２５】
次に、上側線状電極１〜８においては、電力増幅回路８２の出力側の他方に、第１の電極セレクタ８４で選択された１本の上側線状電極３が電流検出回路８３を介して接続され、残りの上側線状電極１、２、４〜８はすべて電力増幅回路８２の出力側の他方に直接接続される。
【００２６】
本実施の形態では、上側線状電極１〜８の配置と下側線状電極Ａ〜Ｈの配置については従来と同様の構成としているが、遮水シートの下側に、下側線状電極Ａ〜Ｈと交差しかつ上側線状電極１〜８と上下方向に重ならないように所定の間隔で並べた複数の増設線状電極１１〜１９を配置している。これらの増設線状電極１１〜１９は、互いに平行に延びる上側線状電極１〜８相互の中間部分にそれぞれ位置しかつ上側線状電極と平行に配置されている。
【００２７】
即ち、図１に示す例では、上側線状電極１〜８と増設線状電極１１〜１９とが下側線状電極Ａ〜Ｈに対して等間隔で交互に交差する形態としている。下側線状電極Ａ〜Ｈにに対する増設線状電極１１〜１９の交差部分には絶縁体３０が設けられている。そして、各増設線状電極１１〜１９は電力増幅回路８２の出力側の他方にそれぞれ接続されている。
【００２８】
その結果、下側線状電極Ｃと残りの全ての線状電極との間に電流が流れるが、電流検出回路８３では下側線状電極Ｃと、選択された上側線状電極３との間に流れる電流のみが検出される。位相検波回路８６は、交流電源８２から出力される印加電圧に同期した位相で電流検出回路８３の位相検波を行う。この位相検波出力は、例えばＡ／Ｄコンバータでディジタル信号に変換され、パソコンのようなコンピュータ（何れも図示せず）に与えられ、画像表示される。
【００２９】
各増設線状電極１１〜１９と、下側線状電極Ａ〜Ｈとの交差部分に設ける絶縁体３０は、各交差部分における増設線状電極と下側線状電極との電気的短絡を防止するためのものである。したがって、短絡防止機能を発揮できればこの絶縁体３０の形状や材質等は特に限定されないが、好ましい態様として、下側線状電極Ａ〜Ｈと増設線状電極１１〜１９との交差部分において、何れか一方の線状電極を被覆する絶縁被覆により形成することができる。
【００３０】
ここでは、図２に示すように下側線状電極Ａ〜Ｈに対して絶縁被覆してなる絶縁体３０が設けられている。この絶縁体３０は、増設線状電極の直径よりも長く形成されている。なお、交差部分が互いに位置ずれしないように、必要に応じて双方を結束する方法を採用することもできる。その場合には、絶縁体３０の長さはさらに短くすることができる。
【００３１】
増設線状電極１１〜１９は、図２に示すように遮水膜１０の下でかつ下側線状電極Ａ〜Ｈの上に配置している。勿論、この増設線状電極１１〜１９は、遮水膜１０の下でかつ下側線状電極Ａ〜Ｈの下に配置することもできるが、図示例のように遮水膜１０の直下に配置する方が好ましい配置関係となる。その理由は、増設線状電極Ａ〜Ｈと上側線状電極１〜８は、電力増幅回路８２の出力側の他方にそれぞれ接続されて同電位となる電極群であるため、上下方向に離す配置とするよりもできるだけ接近させる形態とする方がより一様な電位分布を形成する上で好ましいからである。
【００３２】
この増設線状電極の具体的構成については、電位分布の変化が小さくなるように電場制御を行うという考え方からすれば種々の態様が考えられるが、図１に示すように上側線状電極と平行で、各上側線状電極間の中間に位置するように配置するのが電位分布の変化を全体として小さくかつ一様にする上で好ましい。
【００３３】
また、こうした配置とすることで、従来と比べて格段に電場が制御されると共に、この増設線状電極の存在が測定を阻害するのを未然に防ぐことができる。即ち、これらの増設線状電極が上側線状電極と上下方向で重なっている場合には、電流測定電極となる上側線状電極の周辺にある漏水周辺で、遮水膜１０の上下が同一電位となり、漏水を確認することができなくなる場合があるからである。
【００３４】
また、図示例のように商用交流電源による電圧を線状電極に直接印加するのに代えて、オシレータ等の発振器８１、電力増幅回路８２を用いた場合、高周波成分や自然電流成分をカットして測定安定性を高めることができる。
【００３５】
このような構成において、遮水膜１０に破損が無い場合、遮水膜１０の上下において選択された線状電極３、Ｃ間に流れる電流は遮水膜１０の容量成分を流れる電流となるため、電流の絶対値は小さい値となり、且つ電力増幅回路８２による印加電圧の位相に対しては進み位相となる。一方、遮水膜１０に破損が生じると、破損箇所の上下において選択された線状電極間には電流が流れ易い。このことから、遮水膜１０の上下の線状電極の組合せ交点が破損箇所に近い場合には電流の絶対値は大きくなり、且つ印加電圧の位相に近づく傾向を示す。このことから、上下の線状電極のそれぞれの交点について電流を測定することにより遮水膜１０の破損箇所を検出することが可能になる。
【００３６】
本実施の形態によれば、遮水膜１０の下側に、下側線状電極Ａ〜Ｈと交差しかつ上側線状電極１〜８と上下方向に重ならないように所定の間隔で並べた複数の増設線状電極１１〜１９を配置したことで、下側線状電極に対して上側線状電極と増設線状電極の両方が交差する形態となる。これにより、電極どうしの交差部分が多くなり、その分、全体としての電位分布の変化がより小さくなる。換言すれば、下側線状電極Ａ〜Ｈに沿ってその周辺の電位差がより小さくなる。したがって、電位変化に基づく漏水発生位置の検出が容易となり、その分、測定精度が向上する。
【００３７】
また、遮水膜１０の下側にのみ下側線状電極Ａ〜Ｈに交差する増設線状電極１１〜１９を複数設けるだけであるため、上下の線状電極数を全体的に増やす対策に比べて設備コスト及び施工コストの上昇を抑制することができる。
【００３８】
なお、上記実施の形態では、管理型終末処理場に適用した場合に好適な例を述べたが、水槽、貯水池等の遮水膜を対象として適用することもできる。
【００３９】
【発明の効果】
以上のように、本発明に係る漏水位置検出システムによれば、遮水膜の下側の線状電極と交差する線状電極のみを増設する工夫を凝らすことで、必要な設備コストや施工コストを抑制しつつ、電位分布の変化を全体として小さくし、これにより漏水発生位置検出のための測定精度を格段に向上させることができる。したがって、微小な遮水膜の損傷を通過してくる電流も確実に測定することが可能となる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る漏水位置検出システムの構成を示すブロック図である。
【図２】本発明の実施の形態に係る下側線状電極と増設線状電極との交差部分の構成を示す図１の円Ａ部の拡大断面図である。
【図３】従来の漏水位置検出システムのブロック図である。
【符号の説明】
１〜８上側線状電極
Ａ〜Ｈ下側線状電極
１０遮水膜（遮水材料）
１１〜１９増設線状電極
３０絶縁体
８１発振器
８２電力増幅回路（交流電源）
８３電流検出回路
８４第１の電極セレクタ
８５第２の電極セレクタ
８６位相検波回路[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water leak position detection system in a managed terminal disposal site or the like constructed by laying an insulating water shielding film such as a synthetic resin, a synthetic rubber sheet, or asphalt.
[0002]
[Prior art]
Conventionally, in an artificially managed end-of-use disposal site that uses a water-blocking membrane, groundwater contamination and pollution problems will occur if water leaks, so the water-blocking membrane is regularly inspected and damaged. If this occurs, it is necessary to detect the location of the water leak and perform appropriate repairs.
[0003]
In order to detect the water leakage occurrence position of such a water shielding film, the following detection method is adopted. In this detection method, a plurality of linear electrodes are laid in parallel at a predetermined interval on the lower side of the water shielding film, and a plurality of linear electrodes are arranged on the upper side of the water shielding film at a predetermined interval in a direction intersecting with the lower electrode. An electrode arrangement configuration in which electrodes are laid in parallel is used. In such an electrode arrangement configuration, one linear electrode above and below the water shielding film is selected via the electrode selector, energized by an AC power source between the upper and lower linear electrodes, and flows between the upper and lower linear electrodes. A current is detected, phase detection is performed with a signal synchronized with the phase of the applied voltage, and a leakage occurrence position is detected from a comparison of output voltages of the phase detection circuit at each intersection of the upper and lower linear electrodes.
[0004]
Below, an example of this water leak generation | occurrence | production position detection system is demonstrated with reference to FIG. In this example, the linear electrodes 1 to 8 are arranged on the upper side of the water shielding film (water shielding sheet) 10, and the linear electrodes are arranged on the lower side of the water shielding film 10 in a direction intersecting with the linear electrodes 1 to 8. A to H are arranged. For the first electrode selector 84, when one of the upper linear electrodes 1 to 8 (the linear electrode 3 in FIG. 3) is selected, the remaining linear electrodes have a function of commonly connecting them. Is used. The same applies to the second electrode selector 85.
[0005]
The signal waveform produced by the oscillator 81 is power amplified by the power amplification circuit 82. The power amplifier circuit 82 is connected to the upper linear electrodes 1 to 8 and the lower linear electrodes A to H by the first and second electrode selectors 84 and 85 as follows.
[0006]
First, in the lower linear electrodes A to H, one linear electrode C selected by the second electrode selector 85 is connected to one of the output sides (AC power supply) of the power amplifier circuit 82, and the rest The linear electrodes A, B, and D to H are all directly connected to the other output side of the power amplifier circuit 82.
[0007]
Next, in the upper linear electrodes 1 to 8, one linear electrode 3 selected by the first electrode selector 84 is connected to the other of the output side (AC power supply) of the power amplification circuit 82 and the current detection circuit. The remaining linear electrodes 1, 2, 4 to 8 are all directly connected to the other output side of the power amplifier circuit 82.
[0008]
As a result, a current flows between the upper linear electrode 3 and all the remaining linear electrodes. However, in the current detection circuit 83, the upper linear electrode 3 and the lower selected linear electrode C are connected to each other. Only the current flowing between them is detected. The phase detection circuit 86 performs phase detection of the current detection circuit 83 with a phase synchronized with the applied voltage output from the power amplification circuit 82. This phase detection output is converted into a digital signal by an A / D converter, for example, and is supplied to a computer (not shown) such as a personal computer and displayed as an image.
[0009]
In such a configuration, when there is no breakage in the water shielding film 10, the current flowing between the linear electrodes 3 and C selected above and below the water shielding film 10 becomes a current flowing through the capacitive component of the water shielding film 10. The absolute value of the current is a small value and is a leading phase with respect to the phase of the voltage applied to the power amplifier circuit 82. On the other hand, when the water shielding film 10 is damaged, current easily flows between the linear electrodes selected above and below the damaged portion. From this, when the combined intersection of the upper and lower linear electrodes of the water-shielding film 10 is close to the damaged portion, the absolute value of the current increases and tends to approach the phase of the applied voltage. From this, it becomes possible to detect the damaged part of the water-shielding film 10 by measuring the current at the intersections of the upper and lower linear electrodes.
[0010]
A phase detection circuit 86 is used for current measurement of the conventional detection method, and phase detection is performed on the output of the current detection circuit 83 in a phase synchronized with the applied voltage based on the output of the power amplification circuit 82, and the AC power supply is connected. Synchronous components are extracted.
[0011]
[Problems to be solved by the invention]
By the way, in such a water leak occurrence position detection method, the potential distribution around the linear electrode is uniform as a whole, and the potential changes only in the electrode part to be measured near the water leak position. However, the measurement accuracy is improved. That is, the more uniform the potential is, the easier it is to detect a slight potential change in the uniform potential.
[0012]
In this regard, in the conventional water leak occurrence position detection method, the potential drops rapidly as the distance from the linear electrode increases as the distance from the linear electrode increases. Therefore, a region where the potential difference is rapidly reduced is formed between the front and back surfaces of the water-shielding film, and there is a disadvantage that the magnitude of the current to be measured is reduced in that region. Even if the measured current is small, there is no problem if the current can be measured accurately. However, when a minute water leak is detected, there may be a case where the signal is buried in noise that cannot be removed by the measurement circuit and cannot be detected.
[0013]
As a means for solving this problem, it is conceivable to increase the number of linear electrodes arranged above and below the water shielding film and to reduce the distance between the linear electrodes. However, with this method, a new problem arises in which the necessary equipment cost and construction cost increase in proportion to the increase in the number of linear electrodes.
[0014]
Therefore, the problem of the present invention is to change the potential distribution while suppressing necessary equipment cost and construction cost by elaborating the idea of adding only the linear electrode that intersects the linear electrode on the lower side of the water shielding film. It is to provide a technique capable of improving the measurement accuracy for detecting a leakage occurrence position.
[0015]
[Means for Solving the Problems]
The first means of the present invention includes a plurality of upper linear electrodes arranged at predetermined intervals in parallel to the upper side of the laid water barrier film, and the upper linear electrode in parallel to the lower side of the water barrier film. A plurality of lower linear electrodes arranged at predetermined intervals so as to intersect with each other, a current detection circuit for detecting a current flowing between the upper and lower linear electrodes selected by the selective connection means, and an output of the current detection circuit A phase detection circuit that extracts a current in phase with the phase of the applied voltage from the water leakage position detection system for detecting the water leakage occurrence position from the comparison of the output voltage of the phase detection circuit at each intersection of the upper and lower linear electrodes,
A plurality of additional linear electrodes arranged at a predetermined interval so as to cross the lower linear electrode and not overlap with the upper linear electrode in the vertical direction are arranged below the water shielding film, and the additional lines An insulator for preventing an electrical short circuit is disposed at the intersection of the lower electrode and the lower linear electrode, and the lower linear electrode is connected to one of the AC power sources via the selective connection means, and the additional linear electrode The remaining linear electrodes including are connected to the other side of the AC power source.
[0016]
According to this first means, a plurality of additional linear electrodes arranged at predetermined intervals so as to intersect the lower linear electrode and not to overlap the upper linear electrode in the vertical direction are provided below the water shielding film. By arrange | positioning, it becomes a form where both an upper side linear electrode and an extension linear electrode cross | intersect with respect to a lower side linear electrode. As a result, the number of crossing portions between the electrodes increases, and the change in the potential distribution as a whole becomes smaller accordingly. In other words, the potential difference around the lower linear electrode becomes smaller. Therefore, it becomes easy to detect the water leakage occurrence position based on the potential change, and the measurement accuracy is improved. In addition, since only a plurality of additional linear electrodes crossing the lower linear electrode are provided only on the lower side of the water shielding film, the equipment cost and the construction cost can be reduced compared with the measure for increasing the number of upper and lower linear electrodes as a whole. The rise can be suppressed.
[0017]
In the second means of the present invention, each additional linear electrode is positioned in an intermediate portion between the upper linear electrodes extending in parallel with each other and arranged in parallel with the upper linear electrode. By doing in this way, it becomes a form which an upper side linear electrode and an extension linear electrode cross | intersect with a substantially equal space | interval with respect to a lower side linear electrode. As a result, the change in potential distribution can be made smaller and substantially uniform, and the measurement accuracy can be further improved.
[0018]
In the third means of the present invention, the insulator is formed by an insulating coating that covers at least one of the linear electrodes at the intersection of the lower linear electrode and the additional linear electrode. By using the insulating coating in this way, the insulator can be positioned and provided. Therefore, the electrical short-circuit prevention effect can be surely exhibited, and the workability is improved as compared with the case where an insulator is provided as a separate member.
[0019]
According to a fourth means of the present invention, in a managed terminal treatment plant constructed by laying a water shielding film, a plurality of upper linear electrodes arranged in parallel at a predetermined interval above the water shielding film; A plurality of lower linear electrodes arranged at a predetermined interval so as to intersect the upper linear electrode parallel to the lower side of the water shielding film, an AC power supply, and one of the plurality of upper linear electrodes And selecting one of the plurality of lower linear electrodes, connecting only the selected lower linear electrode to one side of the AC power source, and connecting all the other linear electrodes to the other side of the AC power source. A current detection circuit for detecting a current flowing between the selective connection means, the lower linear electrode connected to one of the AC power supplies, and the one upper linear electrode selected on the opposite side, and Including detection means for receiving the output of the current detection circuit, and detecting a plurality of upper and lower sides When the electrode is selected in sequence and the combination of linear electrodes close to the position of leakage due to breakage of the water shielding film, the output of the detection means rises or falls below the value of the other electrode combination, resulting in water leakage. A processing circuit for detecting a position, and a plurality of additional linear lines arranged below the water shielding film and arranged at predetermined intervals so as to intersect the lower linear electrode and not to overlap the upper linear electrode in the vertical direction Each of the additional linear electrodes is provided with an insulator for preventing an electrical short circuit at each of the intersections. It was set as the structure connected to the other of each.
[0020]
According to such a configuration, a current flows between one lower linear electrode connected to one of the AC power supplies and all other linear electrodes connected to the other of the AC power supply. Is configured to be performed only on one upper linear electrode selected on the opposite side through the water shielding film. Because of this, the current measurement limited to the intersection between the lower electrode connected to one side of the AC power source and the upper linear electrode on the opposite side where current measurement is performed is performed, so that the water shielding film is damaged. The accuracy of detecting is improved. In addition to this, by arranging a plurality of additional linear electrodes intersecting with the lower linear electrode, these additional linear electrodes exert an electric field control action, and the periphery along the lower linear electrode. The change in the potential distribution becomes smaller. Therefore, it becomes easy to detect the water leakage occurrence position based on the potential change, and the measurement accuracy is remarkably improved.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing the configuration of the embodiment of the present invention. As in the prior art, the upper linear electrodes 1 to 8 are arranged on the water shielding film (water shielding sheet) 10, and the lower linear shape is formed below the water shielding film 10 in the direction intersecting with the upper linear electrodes 1 to 8. Electrodes A to H are arranged respectively.
[0022]
The first electrode selector 84 has a function of selecting one of the upper linear electrodes 1 to 8 (the linear electrode 3 in FIG. 1) and connecting the remaining upper linear electrodes in common. Is used. The same applies to the second electrode selector 85.
[0023]
The signal waveform produced by the oscillator 81 is power amplified by the power amplification circuit 82. The power amplification circuit 82 is connected to the upper linear electrodes 1 to 8 and the lower linear electrodes A to H by the first and second electrode selectors 84 and 85 as follows.
[0024]
First, in the lower linear electrodes A to H, one linear electrode C selected by the second electrode selector 85 is connected to one of the output sides of the power amplifier circuit 82, and the remaining linear electrodes A, B and D to H are all directly connected to the other output side of the power amplifier circuit 82.
[0025]
Next, in the upper linear electrodes 1 to 8, one upper linear electrode 3 selected by the first electrode selector 84 is connected to the other output side of the power amplifier circuit 82 via the current detection circuit 83. The remaining upper linear electrodes 1, 2, 4 to 8 are all directly connected to the other output side of the power amplifier circuit 82.
[0026]
In the present embodiment, the arrangement of the upper linear electrodes 1 to 8 and the arrangement of the lower linear electrodes A to H are the same as the conventional configuration, but the lower linear electrode A to the lower side of the water shielding sheet. A plurality of additional linear electrodes 11 to 19 that are arranged at a predetermined interval so as to cross H and not to overlap the upper linear electrodes 1 to 8 in the vertical direction are arranged. These additional linear electrodes 11 to 19 are respectively located in the middle portions of the upper linear electrodes 1 to 8 extending in parallel with each other and arranged in parallel to the upper linear electrodes.
[0027]
That is, in the example shown in FIG. 1, the upper linear electrodes 1 to 8 and the additional linear electrodes 11 to 19 alternately intersect the lower linear electrodes A to H at equal intervals. An insulator 30 is provided at the intersection of the additional linear electrodes 11 to 19 with respect to the lower linear electrodes A to H. Each of the additional linear electrodes 11 to 19 is connected to the other output side of the power amplifier circuit 82.
[0028]
As a result, a current flows between the lower linear electrode C and all the remaining linear electrodes. In the current detection circuit 83, a current flows between the lower linear electrode C and the selected upper linear electrode 3. Only current is detected. The phase detection circuit 86 performs phase detection of the current detection circuit 83 at a phase synchronized with the applied voltage output from the AC power supply 82. This phase detection output is converted into a digital signal by an A / D converter, for example, and is supplied to a computer (not shown) such as a personal computer and displayed as an image.
[0029]
The insulator 30 provided at the intersection of each of the additional linear electrodes 11 to 19 and the lower linear electrodes A to H is for preventing an electrical short circuit between the additional linear electrode and the lower linear electrode at each of the intersections. belongs to. Therefore, the shape and material of the insulator 30 are not particularly limited as long as the short-circuit prevention function can be exhibited. However, as a preferable aspect, any one of the crossing portions between the lower linear electrodes A to H and the additional linear electrodes 11 to 19 can be used. It can form by the insulation coating which coat | covers one linear electrode.
[0030]
Here, as shown in FIG. 2, an insulator 30 is provided which is provided with an insulating coating on the lower linear electrodes A to H. The insulator 30 is formed longer than the diameter of the additional linear electrode. It is also possible to employ a method of binding both parts as necessary so that the intersecting portions are not displaced from each other. In that case, the length of the insulator 30 can be further shortened.
[0031]
As shown in FIG. 2, the extended linear electrodes 11 to 19 are disposed below the water shielding film 10 and above the lower linear electrodes A to H. Of course, the additional linear electrodes 11 to 19 can be arranged under the water shielding film 10 and under the lower linear electrodes A to H, but are arranged directly under the water shielding film 10 as shown in the drawing. It is preferable to do this. The reason is that the extended linear electrodes A to H and the upper linear electrodes 1 to 8 are connected to the other of the output sides of the power amplifier circuit 82 and have the same potential. This is because it is preferable to make the configuration as close as possible to form a more uniform potential distribution.
[0032]
With regard to the specific configuration of the additional linear electrode, various modes can be considered from the viewpoint that electric field control is performed so that the change in potential distribution becomes small. However, as shown in FIG. 1, it is parallel to the upper linear electrode. Therefore, it is preferable to arrange the electrodes so as to be positioned between the upper linear electrodes in order to make the change in potential distribution small and uniform as a whole.
[0033]
In addition, with such an arrangement, the electric field is significantly controlled as compared with the conventional case, and the presence of the additional linear electrode can be prevented from obstructing the measurement. That is, when these additional linear electrodes overlap with the upper linear electrodes in the vertical direction, the upper and lower sides of the water shielding film 10 are at the same potential around the water leakage around the upper linear electrodes serving as current measuring electrodes. This is because there is a case where water leakage cannot be confirmed.
[0034]
Also, instead of directly applying the voltage from the commercial AC power source to the linear electrode as shown in the example, when using the oscillator 81 such as an oscillator and the power amplification circuit 82, the high frequency component and the natural current component are cut off. Measurement stability can be improved.
[0035]
In such a configuration, when there is no breakage in the water shielding film 10, the current flowing between the linear electrodes 3 and C selected above and below the water shielding film 10 becomes a current flowing through the capacitive component of the water shielding film 10. The absolute value of the current is a small value, and is a leading phase with respect to the phase of the voltage applied by the power amplifier circuit 82. On the other hand, when the water shielding film 10 is damaged, current easily flows between the linear electrodes selected above and below the damaged portion. From this, when the combined intersection of the upper and lower linear electrodes of the water-shielding film 10 is close to the damaged portion, the absolute value of the current increases and tends to approach the phase of the applied voltage. From this, it becomes possible to detect the damaged part of the water-shielding film 10 by measuring the current at the intersections of the upper and lower linear electrodes.
[0036]
According to the present embodiment, a plurality of lines arranged at predetermined intervals below the water shielding film 10 so as to intersect the lower linear electrodes A to H and not to overlap the upper linear electrodes 1 to 8 in the vertical direction. Since the additional linear electrodes 11 to 19 are arranged, both the upper linear electrode and the additional linear electrode intersect with the lower linear electrode. As a result, the number of crossing portions between the electrodes increases, and the change in the potential distribution as a whole becomes smaller accordingly. In other words, the potential difference around the lower linear electrodes A to H becomes smaller. Therefore, it becomes easy to detect the water leakage occurrence position based on the potential change, and the measurement accuracy is improved accordingly.
[0037]
Further, since only a plurality of additional linear electrodes 11 to 19 intersecting with the lower linear electrodes A to H are provided only on the lower side of the water shielding film 10, compared with a measure for increasing the number of upper and lower linear electrodes as a whole. Thus, increase in equipment cost and construction cost can be suppressed.
[0038]
In addition, in the said embodiment, although the example suitable when applied to a management type | mold terminal treatment plant was described, it can also apply to water-impervious films, such as a water tank and a reservoir.
[0039]
【The invention's effect】
As described above, according to the water leakage position detection system according to the present invention, necessary equipment costs and construction costs can be obtained by elaborating the idea of adding only the linear electrodes that intersect the linear electrodes on the lower side of the water shielding film. As a whole, the change in the potential distribution is reduced, and the measurement accuracy for detecting the water leakage occurrence position can be remarkably improved. Therefore, it is possible to reliably measure the current passing through the damage of the minute water shielding film.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a water leakage position detection system according to an embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of a circle A portion in FIG. 1 showing a configuration of an intersecting portion between a lower linear electrode and an additional linear electrode according to the embodiment of the present invention.
FIG. 3 is a block diagram of a conventional water leakage position detection system.
[Explanation of symbols]
1-8 Upper linear electrode A-H Lower linear electrode 10 Water shielding film (water shielding material)
11 to 19 Additional linear electrode 30 Insulator 81 Oscillator 82 Power amplification circuit (AC power supply)
83 Current detection circuit 84 First electrode selector 85 Second electrode selector 86 Phase detection circuit

Claims

A plurality of upper linear electrodes arranged at a predetermined interval in parallel with the upper side of the laid water barrier film, and at a predetermined interval so as to intersect the upper linear electrode in parallel with the lower side of the water barrier film. A plurality of lower linear electrodes arranged, a current detection circuit for detecting a current flowing between the upper and lower linear electrodes selected by the selective connection means, and a current in phase with the phase of the applied voltage from the output of the current detection circuit In the water leakage position detection system for detecting the water leakage occurrence position from the comparison of the output voltage of the phase detection circuit at each intersection of the upper and lower linear electrodes,
A plurality of additional linear electrodes arranged at a predetermined interval so as to cross the lower linear electrode and not overlap with the upper linear electrode in the vertical direction are arranged below the water shielding film, and the additional lines An insulator for preventing an electrical short circuit is disposed at the intersection of the lower electrode and the lower linear electrode, and the lower linear electrode is connected to one of the AC power sources via the selective connection means, and the additional linear electrode The remaining linear electrode including is connected to the other side of the AC power supply, the water leakage position detection system.

The water leakage position detection system according to claim 1, wherein each of the additional linear electrodes is located in an intermediate portion between the upper linear electrodes extending in parallel with each other and arranged in parallel with the upper linear electrode.

3. The water leakage position detection system according to claim 1, wherein the insulator is formed by an insulating coating that covers at least one of the linear electrodes at an intersection between the lower linear electrode and the additional linear electrode.

In the management-type terminal treatment plant constructed by laying a water shielding film,
A plurality of upper linear electrodes arranged at predetermined intervals in parallel with the upper side of the water shielding film;
A plurality of lower linear electrodes arranged at a predetermined interval so as to intersect the upper linear electrode in parallel with the lower side of the water shielding film;
AC power supply,
Select one of the plurality of upper linear electrodes, select one of the plurality of lower linear electrodes, connect only the selected lower linear electrode to one of the AC power supplies, and select the other linear electrode Are all selective connection means for connecting to the other of the AC power source,
A current detection circuit for detecting a current flowing between a lower linear electrode connected to one side of the AC power source and one upper linear electrode selected on the opposite side;
It includes detection means that receives the output of this current detection circuit and performs detection, and selects a plurality of upper and lower linear electrodes in sequence, resulting in a combination of linear electrodes that are close to the location of water leakage due to damage to the water shielding film. A processing circuit for detecting a leakage occurrence position because the output of the detection means rises or falls below the value of the other electrode combination when
A plurality of additional linear electrodes arranged below at a predetermined interval so as not to cross the lower linear electrode and overlap the upper linear electrode in the vertical direction below the water shielding film,
Provided respectively at the intersection of the additional linear electrode and the lower linear electrode, and comprises an insulator for preventing an electrical short circuit at each intersection,
Each of the additional linear electrodes is connected to the other side of the AC power supply, and the water leakage position detection system.