JPS642227B2 - - Google Patents
Info
- Publication number
- JPS642227B2 JPS642227B2 JP56086491A JP8649181A JPS642227B2 JP S642227 B2 JPS642227 B2 JP S642227B2 JP 56086491 A JP56086491 A JP 56086491A JP 8649181 A JP8649181 A JP 8649181A JP S642227 B2 JPS642227 B2 JP S642227B2
- Authority
- JP
- Japan
- Prior art keywords
- conductor
- buried
- line
- magnetic field
- measured
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000004020 conductor Substances 0.000 claims description 66
- 238000005259 measurement Methods 0.000 claims description 35
- 239000002131 composite material Substances 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 10
- 238000009434 installation Methods 0.000 claims description 2
- 238000001514 detection method Methods 0.000 description 30
- 238000010586 diagram Methods 0.000 description 10
- 230000007246 mechanism Effects 0.000 description 9
- 238000009933 burial Methods 0.000 description 6
- 238000012545 processing Methods 0.000 description 5
- 230000000630 rising effect Effects 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 230000005674 electromagnetic induction Effects 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000009412 basement excavation Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V3/00—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
- G01V3/02—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with propagation of electric current
- G01V3/06—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with propagation of electric current using ac
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Geology (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- Geophysics (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Geophysics And Detection Of Objects (AREA)
Description
【発明の詳細な説明】
この発明はガス導管、水道管、電力ケーブル、
パイプライン等の地下埋設導体の埋設位置検出方
法に関する。[Detailed Description of the Invention] This invention relates to gas pipes, water pipes, power cables,
This invention relates to a method for detecting the buried position of underground conductors such as pipelines.
地下に埋設されているガス管や水道管などの埋
設位置を地表上から検出する計測技術は掘削工事
や建設工事などの際に管体の破損を避けるために
必要不可欠となつている。従来このような地下埋
設導体の検出方法としては電磁誘導を使用したも
のが知られている。これは第１図に示すように送
信器１および受信器２を設け、上記送信器１を接
地するとともにリード線３，４を介して埋設導体
５に接続して閉ループを形成し、その閉ループに
送信器１から交流電流を流すことによつて埋設導
体５の周囲に交番磁界Ｈを発生させ、その交番磁
界をコイルを有する検知棒６で検知して上記受信
器２に入力するようにした直接通電方式といわれ
るものである。これは埋設導体５に流れる交流電
流によつて発生する交番磁界が埋設導体５を中心
に同心円状になるものと仮定し、磁界の方向が検
知棒６内のコイルと平行になると検知コイルに発
生する誘導起電力がゼロになることを利用したも
ので、検知棒６を90゜にして誘導起電力がゼロと
なる地点を捜し、その地点を埋設導体５の真上と
仮定し、また検知棒６を45゜に傾けて誘導起電力
がゼロとなる地点を捜し、その両地点間距離と角
度45゜から三角法により埋設導体５の埋設深さを
検出するようにしている。しかし実際は埋設導体
５と接地ラインとの間に大地の静電容量を介して
帰路電流が流れるため発生する交番磁界は埋設導
体を中心とした同心円状になることはない。この
ためこの方法ではかならず測定誤差が生じ、その
誤差も場合によつては20〜50％にもなり、埋設位
置を精度よく計測することが求められるものには
使用することができない欠点があつた。 Measurement technology that detects the location of gas pipes, water pipes, etc. buried underground from above the ground has become essential to avoid damage to pipe bodies during excavation and construction work. Conventionally, a method using electromagnetic induction is known as a method for detecting such underground conductors. As shown in Fig. 1, a transmitter 1 and a receiver 2 are provided, and the transmitter 1 is grounded and connected to a buried conductor 5 via lead wires 3 and 4 to form a closed loop. An alternating magnetic field H is generated around the buried conductor 5 by passing an alternating current from the transmitter 1, and the alternating magnetic field is detected by a detection rod 6 having a coil and inputted to the receiver 2. This is called the energizing method. This assumes that the alternating magnetic field generated by the alternating current flowing through the buried conductor 5 is concentric with the buried conductor 5, and when the direction of the magnetic field becomes parallel to the coil in the detection rod 6, it is generated in the detection coil. This method takes advantage of the fact that the induced electromotive force becomes zero when the detection rod 6 is turned to 90 degrees, searches for a point where the induced electromotive force becomes zero, assumes that point is directly above the buried conductor 5, and 6 is tilted at 45 degrees to find a point where the induced electromotive force becomes zero, and the buried depth of the buried conductor 5 is detected by trigonometry from the distance between the two points and the 45 degree angle. However, in reality, since a return current flows between the buried conductor 5 and the ground line via the ground capacitance, the generated alternating magnetic field does not form concentric circles around the buried conductor. For this reason, this method always has a measurement error, and in some cases, the error is as high as 20 to 50%, making it unsuitable for applications that require accurate measurement of buried locations. .
この発明はこのような欠点を除去するために為
されたもので、地下埋設導体の埋設位置を精度良
く測定することができ、しかも測定に必要なスペ
ースが少なくてよく実用性が高い地下埋設導体の
埋設位置検出方法を提供することを目的とする。 This invention was made in order to eliminate these drawbacks, and it is possible to accurately measure the buried position of an underground conductor, and moreover, it requires less space for measurement and is highly practical. The purpose of this invention is to provide a method for detecting the buried position of
この発明は電磁誘導型直接通電方式をその基本
としつつ帰路電流用線路を設けて帰路電流の経路
を明確にするとともに、その帰路電流用線路の敷
設位置を変えたときの導体と線路から発生する磁
界の合成磁界の方向の変化を導体の片側面外側に
位置する地表上の垂直方向又は水平方向にずれた
２点において計測することにより導体の埋設位置
を検出するものである。 This invention is based on an electromagnetic induction type direct energization method, and also provides a return current line to clarify the path of the return current, and also to reduce the amount of electricity generated from the conductor and line when the return current line is relocated. The buried position of the conductor is detected by measuring changes in the direction of the composite magnetic field at two points on the ground surface located outside one side of the conductor and shifted in the vertical or horizontal direction.
次にこの発明の検出原理について述べる。第２
図に示すように互に距離Ｌだけ離れた線路l1，l2
に互に等しくかつ方向の異なる交流電流が流れた
場合に、線路l1からｘ方向に距離Ｘ、ｙ方向に距
離Ｙ離れたＰ点の磁界の強さＨのｘ成分、ｙ成分
は次式で与えられることが知られている。 Next, the detection principle of this invention will be described. Second
As shown in the figure, the lines l 1 and l 2 are separated by a distance L from each other.
When alternating currents that are equal and have different directions flow through the lines, the x and y components of the magnetic field strength H at point P , which is a distance X in the x direction and a distance Y in the y direction from the line l1, are calculated by the following equations. It is known that it is given by
HX＝−１／2π（Ｙ／R1−Ｌ＋Ｙ／R2）……(1)
HY＝１／2π（Ｘ／R1−Ｘ／R2） ……(2)
但し、R1＝X2＋Y1、R2＝X2＋（Ｌ＋Ｙ）2
Ｉは電流値
そしてＰ点における磁界の方向θは
θ＝tan-1（Hy／Hx） ……(3)
となる。これは換言すればＰ点の座標（Ｘ、Ｙ）
及びＰ点の磁界の方向θを計測すれば線路l1，l2
間の距離Ｌを求めることができる。したがつて第
３図に示すように埋設導体１１に枝管１２や防食
用ターミナル１３等を使用して地表上に配置され
る帰路電流用線路１４および増幅機能付発信器１
５を接続して閉ループを形成すれば導体１１と線
路１４は往復電流路となる。したがつて図中Ｐ点
における磁界方向を計測すれば前記(1)、(2)、(3)式
によつて帰路電流用線路１４と埋設導体１１との
距離、すなわち導体１１の埋設深さＤを求めるこ
とができる。特に第２図におけるＹが「０」、即
ち磁界の計測点Ｐが地表面にある場合、上記第(3)
式は
θ＝tan-1（Ｌ／Ｘ） ………（3a）
となる。つまり、この式は合成磁界のベクトルの
向きが埋設された導体から計測点Ｐに向つた方向
であることを表わしている。しかるに、合成磁界
の方向に対して180゜の方向でかつ帰路電流線路の
真下に埋設導体が位置することがわかる。 H _ _ _ _ _ _ X 2 +Y 1 , R 2 =X 2 +(L+Y) 2 I is the current value, and the direction θ of the magnetic field at point P is θ=tan -1 (H y /H x )...(3). In other words, the coordinates of point P (X, Y)
And if the direction θ of the magnetic field at point P is measured, the lines l 1 , l 2
The distance L between them can be found. Therefore, as shown in FIG. 3, a return current line 14 and an amplification function oscillator 1 are installed on the ground surface using branch pipes 12, anti-corrosion terminals 13, etc. on the buried conductor 11.
If the conductor 11 and the line 14 are connected to form a closed loop, the conductor 11 and the line 14 become a reciprocating current path. Therefore, if the direction of the magnetic field at point P in the figure is measured, the distance between the return current line 14 and the buried conductor 11, that is, the buried depth of the conductor 11, can be determined by equations (1), (2), and (3) above. D can be found. In particular, when Y in Figure 2 is "0", that is, the magnetic field measurement point P is on the ground surface, the above (3)
The formula is θ=tan -1 (L/X) (3a). In other words, this equation indicates that the direction of the vector of the composite magnetic field is the direction from the buried conductor to the measurement point P. However, it can be seen that the buried conductor is located at a direction of 180° to the direction of the composite magnetic field and directly below the return current line.
このように本発明における第１の特徴は帰路電
流用線路を設けることにより帰路電流の経路を明
確にして導体１１の埋設深さを検出するようにし
たことである。 As described above, the first feature of the present invention is that by providing a return current line, the path of the return current is made clear and the buried depth of the conductor 11 is detected.
前記(1)、(2)、(3)式によつて埋設導体１１の埋設
深さを正確に検出するには帰路電流用線路１４が
埋設導体１１の真上に位置する必要があり、これ
がずれると誤差が生じる。例えば第４図に示すよ
うに埋設導体１１の中心から横に２ｍ離れた位置
の真上になる地表上を測定点P0とし、線路１４
が導体１１の真上になる地表上の点より測定点
P0側に20mm（＋20mm）ずれた位置に配置された
ときの埋設深さＤと誤差ΔDとの関係を示すと第
５図のグラフのようになり、また非測定点側に
20mm（（−20mm）ずれた位置に配置されたときの
埋設深さＤと誤差ΔDとの関係を示すと第５図の
グラフのようになる。本発明における第２の特
徴はこの誤差を利用したことである。この点につ
いて以下第６図及び第７図を用いて詳細に説明す
る。なお、以下の説明においては簡単のために第
２図におけるＹを「０」、即ち磁界の計測点Ｐを
地表面にあるものとして説明する。Ｙ≠０の場合
は、式が複雑になり数値計算が必要となるが結論
は変わらない。又、測定において実際の埋設導体
の位置は不明であるので、常に埋設導体が帰路電
流線路の真下にあるものと仮定して測定を行なう
こととする。しかるに、上述したようにこのよう
な条件の下に測定を行えば、合成磁界の方向に対
して180゜の方向でかつ帰路電流線路の真下に埋設
導体が位置するものとして埋設導体の位置測定が
できる。第６図に示すように深さD0の位置に埋
設した導体１１の真上として仮定した地表上の
O′点の片側におけるP1，P2の２点を測定点とし、
そのO′点から距離ａの位置に線路１４を配置し、
その線路１４が導体１１の真上に位置するＯ点よ
りも距離ｌだけ離れ、かつP1点がＯ点よりもl1離
れているとともにP2点がＯ点よりもl2離れている
とするとP1点、P2点における磁界方向θ10、θ20は
θ10＝tan-1l1・ｌ＋D0 2／D0（l1−ｌ） ……(4)
θ20＝tan-1l2・ｌ＋D0 2／D0（l2−ｌ） ……(5)
となり、P1点、P2点における測定埋設深さDp1、
Dp2は
Dp1＝（l1−ｌ）tanθ10 ……(6)
Dp2＝（l2−ｌ）tanθ20 ……(7)
となる。 In order to accurately detect the buried depth of the buried conductor 11 using equations (1), (2), and (3) above, the return current line 14 must be located directly above the buried conductor 11. If it deviates, an error will occur. For example , as shown in FIG.
The measurement point is from the point on the ground surface where is directly above the conductor 11.
The relationship between the burial depth D and the error ΔD when placed at a position shifted by 20 mm (+20 mm) toward the P 0 side is shown in the graph in Figure 5.
The relationship between the burial depth D and the error ΔD when placed at a position shifted by 20 mm ((-20 mm) is shown in the graph in Figure 5. The second feature of the present invention is to utilize this error. This point will be explained in detail below using Figs. 6 and 7. In the following explanation, for the sake of simplicity, Y in Fig. 2 is set to "0", that is, the measurement point of the magnetic field. We will explain P as being on the ground surface.If Y≠0, the formula becomes complicated and numerical calculations are required, but the conclusion remains the same.Also, since the actual location of the buried conductor is unknown during measurement, , the buried conductor is always assumed to be directly below the return current line.However, if measurements are made under these conditions as described above, the direction of the combined magnetic field is 180°. The position of the buried conductor can be measured assuming that the buried conductor is located directly below the return current line in the direction of on the ground
Two points P 1 and P 2 on one side of point O′ are the measurement points,
Place the track 14 at a distance a from the point O',
If the line 14 is separated by a distance l from the point O located directly above the conductor 11, and the point P1 is separated by l1 from the point O, and the point P2 is separated by l2 from the point O. Then, the magnetic field directions θ 10 and θ 20 at points P 1 and P 2 are θ 10 = tan -1 l 1 · l + D 0 2 /D 0 (l 1 - l) ...(4) θ 20 = tan -1 l 2・l+D 0 2 /D 0 (l 2 −l) ...(5), and the measured burial depth D p1 at point P 1 and point P 2 ,
D p2 becomes D p1 = (l 1 - l) tan θ 10 ... (6) D p2 = (l 2 - l) tan θ 20 ... (7).
この測定を線路１４の敷設位置を変化させてす
なわち距離ａを変化させて複数回行なう。例えば
実際の深さが2.0ｍでOO′間の距離が0.1ｍのとき
においてａを0.2ｍ〜−0.3ｍにして測定点P1，P2
において測定した埋設深さの変化をグラフに示す
と第７図に示すようなグラフ○イ、○ロが得られた。
このことから両測定点P1，P2において測定した
埋設深さがDp1＝Dp2となる交点Ｃにおいて真の
深さ2.0ｍが得られることがわかる。すなわちグ
ラフ○イ、○ロの交点ＣはDp1＝Dp2のときであるか
ら上記(4)、(5)、(6)、(7)の各式より
l1・ｌ＋D0 2＝l2・ｌ＋D0 2
ｌ（l1−l2）＝Ｏ ……(8)
ここでl1≠l2であるから上記(8)式が成り立つた
めにはｌ＝Ｏである。このときDp1＝Dp2＝D0と
なる。したがつてグラフの交叉点Ｃは埋設物の水
平、垂直位置となる。なお、グラフ○ハはP2′点に
おいて測定した埋設深さであり、またグラフ○ニは
P1′点において測定した埋設深さである。 This measurement is performed multiple times by changing the laying position of the line 14, that is, by changing the distance a. For example, when the actual depth is 2.0 m and the distance between OO' is 0.1 m, set a to 0.2 m to -0.3 m and measure points P 1 and P 2
When the changes in the buried depth measured in the above are shown in a graph, graphs ○A and ○B as shown in FIG. 7 were obtained.
From this, it can be seen that a true depth of 2.0 m is obtained at the intersection C where the buried depth measured at both measurement points P 1 and P 2 is D p1 =D p2 . In other words, the intersection C of graphs ○A and ○B is when D p1 = D p2 , so from the above equations (4), (5), (6), and (7), l 1 · l + D 0 2 = l 2・l+D 0 2 l(l 1 −l 2 )=O (8) Here, since l 1 ≠ l 2 , l=O in order for the above equation (8) to hold true. At this time, D p1 =D p2 =D 0 . Therefore, the intersection point C of the graph is the horizontal and vertical position of the buried object. In addition, graph ○C is the burial depth measured at point P 2 ′, and graph ○D is the burial depth measured at point P 2 ′.
This is the burial depth measured at point P 1 ′.
このように本発明によれば、地下に埋設された
導体１１と略平行するように帰路電流用線路１４
を地表上に配設して導体１１及び線路１４を対向
辺とする方形状の閉ループを形成し、この閉ルー
プに交流電流を通流させて交番磁界を発生させ、
導体１１による磁界と線路１４による磁界との合
成磁界の方向を導体１１の片側に位置する地表上
の２点P1，P2（又はP1′，P2′）において計測し、
導体１１が線路１４の真下にあると仮定して合成
磁界の方向の計測値より導体１１の埋設深さを測
定し、この合成磁界の方向の計測と埋設深さの測
定とを線路１４の配設位置を変化させて複数回行
い、このときの２点P1，P2（又はP1′，P2′）にお
ける埋設深さの各測定値が一致する値の線路１４
の位置及び導体１１の埋設深さの計測値から導体
１１の地下埋設位置が正確に検出できる。 As described above, according to the present invention, the return current line 14 is arranged substantially parallel to the conductor 11 buried underground.
is arranged on the ground surface to form a rectangular closed loop with the conductor 11 and the line 14 as opposite sides, and an alternating current is passed through this closed loop to generate an alternating magnetic field,
The direction of the composite magnetic field of the magnetic field due to the conductor 11 and the magnetic field due to the line 14 is measured at two points P 1 and P 2 (or P 1 ′, P 2 ′) on the ground surface located on one side of the conductor 11,
Assuming that the conductor 11 is located directly below the line 14, the buried depth of the conductor 11 is measured from the measured value of the direction of the composite magnetic field, and the measurement of the direction of the composite magnetic field and the measurement of the buried depth are combined with the direction of the line 14. The line 14 was measured several times by changing the installation position, and each measurement value of the buried depth at the two points P 1 and P 2 (or P 1 ′, P 2 ′) coincided with each other.
The underground position of the conductor 11 can be accurately detected from the measured value of the position and the buried depth of the conductor 11.
次にこの発明の実施例について図面を参照して
説明する。 Next, embodiments of the invention will be described with reference to the drawings.
第８図に示すように導体１１が埋設されている
地表上に帰路電流用線路１４を配設し、その線路
１４の一端を立上げ線１６を介して上記導体１１
の一端側に接続するとともにその線路１４の他端
を送信装置１７および立上げ線１８を介して上記
導体１１の他端側に接続し閉ループを形成してい
る。前記送信装置１７は第９図に示すように発信
器１９から信号を電力増幅器２０を介して増幅さ
せ、その増幅した信号を線路１４および立上げ線
１６を介して導体１１に供給している。同時に線
路１４に流れる電流値を電流測定器２１によつて
計測し、一定値以上の電流値となるよう電力増幅
器２０の増幅率を調整する。地表上のP1点およ
びこのP1点よりもｈｍ高いP2点をそれぞれ測定
点とし、その測定点には第１０図に示す検出装置
２２を設置する。この検出装置２２は所定の間隔
をあけて対向立設された支持部２３ａ，２３ｂを
有する治具２４の上記支持部２３ａ，２３ｂの上
方に軸受２５ａ，２５ｂを設け、その軸受２５
ａ，２５ｂ間に円柱状の保持機構２６を回転自在
に設けている。そして前記保持機構２６に検出コ
イル２７を取付けている。前記検出コイル２７か
ら発生する誘導起電力信号は信号増幅器２８を介
して演算処理装置２９に入力している。また前記
検出コイル２７の地表に対する傾きはジヨイント
機構３０を介して前記保持機構２６とその同軸上
に結合した高精度角度計３１によつて測定され前
記演算処理装置２９に入力される。前記検出装置
２２は検出コイル２７を保持機構２６を滑らかに
低速度で回転させることによつて少しずつ傾かせ
検出コイル２７に発生する誘導起電力が最小にな
つたときの検出コイル２７の傾きθを高精度角度
計３１から得るようにしている。そして演算処理
装置２９によつて角度θと測定点P1，P2の地表
上の座標（Ｘ、Ｙ）とからDp1，Dp2を算出する
ようにしている。 As shown in FIG. 8, a return current line 14 is arranged on the ground surface where the conductor 11 is buried, and one end of the line 14 is connected to the conductor 11 through the rising line 16.
The line 14 is connected to one end of the conductor 11, and the other end of the line 14 is connected to the other end of the conductor 11 via a transmitting device 17 and a rising line 18 to form a closed loop. As shown in FIG. 9, the transmitting device 17 amplifies a signal from a transmitter 19 via a power amplifier 20, and supplies the amplified signal to the conductor 11 via a line 14 and a rising line 16. At the same time, the current value flowing through the line 14 is measured by the current measuring device 21, and the amplification factor of the power amplifier 20 is adjusted so that the current value is equal to or higher than a certain value. A point P1 on the ground surface and a point P2 hm higher than the point P1 are defined as measurement points, and a detection device 22 shown in FIG. 10 is installed at the measurement points. This detection device 22 includes bearings 25a and 25b provided above the support portions 23a and 23b of a jig 24 having support portions 23a and 23b facing each other at a predetermined interval.
A cylindrical holding mechanism 26 is rotatably provided between a and 25b. A detection coil 27 is attached to the holding mechanism 26. The induced electromotive force signal generated from the detection coil 27 is input to an arithmetic processing unit 29 via a signal amplifier 28. Further, the inclination of the detection coil 27 with respect to the ground surface is measured by a high-precision angle meter 31 coaxially connected to the holding mechanism 26 via a joint mechanism 30, and is input to the arithmetic processing unit 29. The detection device 22 tilts the detection coil 27 little by little by rotating the holding mechanism 26 smoothly at a low speed, so that the inclination θ of the detection coil 27 is determined when the induced electromotive force generated in the detection coil 27 is minimized. is obtained from a high-precision angle meter 31. Then, the arithmetic processing unit 29 calculates D p1 and D p2 from the angle θ and the coordinates (X, Y) of the measurement points P 1 and P 2 on the earth's surface.
このように構成された本発明実施例装置を使用
して例えば第１１図に示すように地表GH上に立
設された金属フエンスＦから距離ｄ＝3085mm離れ
た地表点下ｘ＝1803mmの深さに直径300mmで長さ
60ｍの鋼管Ｓを埋設して実験を行なつた結果鋼管
Ｓの水平位置については＋６cmの誤差が生じ、垂
直位置については1840mmで＋37mmの誤差が生じ
た。これを第１図に示す従来方式で行なつたとこ
ろ水平位置で＋430mmの誤差が生じこのため垂直
位置ではさらに誤差が生じ測定が困難になつた。
このように鋼管の埋設位置（水平位置と垂直位
置）をかなり高い精度で測定することができる。
また測定点P1，P2としては埋設導体１１の片側
のみに設定することができ、したがつて導体１１
が道路際のように他の片側に測定点を設置するの
が困難なスペース的に限られた場所に埋設されて
いても充分に測定することができ実用性を向上で
きる。さらに測定点を導体１１の片側にしたこと
により、導体１１が例えば車道と歩道の境目近く
に埋まつていたり、フエンスの近くに埋まつてい
たりした場合に、車道側やフエンスの反対側に測
定点を設ける事無く測定ができる。実際の埋設管
はこのような場所に埋設されることが多いので、
これは極めて有用である。 For example, as shown in FIG. 11, using the device according to the embodiment of the present invention configured as described above, a distance d = 3085 mm from the metal fence F erected on the ground surface GH is placed at a depth of x = 1803 mm below the ground surface. Diameter 300mm in length
As a result of conducting an experiment with a 60 m steel pipe S buried, an error of +6 cm occurred in the horizontal position of the steel pipe S, and an error of +37 mm in the vertical position at 1840 mm. When this was done using the conventional method shown in FIG. 1, an error of +430 mm occurred in the horizontal position, which caused an even greater error in the vertical position, making measurement difficult.
In this way, the buried position (horizontal and vertical position) of the steel pipe can be measured with fairly high accuracy.
Moreover, the measurement points P 1 and P 2 can be set only on one side of the buried conductor 11, so that the measurement points P 1 and P 2 can be set only on one side of the buried conductor 11.
Even if the sensor is buried in a space-limited location where it is difficult to install a measuring point on the other side, such as near a road, sufficient measurements can be made, and practicality can be improved. Furthermore, by setting the measurement point to one side of the conductor 11, if the conductor 11 is buried near the boundary between the road and the sidewalk, or buried near the fence, the measurement point will be measured on the road side or the opposite side of the fence. Measurement can be performed without setting up points. Actual buried pipes are often buried in places like this, so
This is extremely useful.
なお、前記実施例では測定点P1，P2を同一垂
直面内に設けたものについて述べたがかならずし
もこれに限定されるものではなく、同一水平面内
又は垂直面と水平面との組合わせた位置に設けて
もよい。 In the above embodiment, the measurement points P 1 and P 2 were provided in the same vertical plane, but the measurement points are not limited to this, and the measurement points P 1 and P 2 may be located in the same horizontal plane or in a combination of the vertical plane and the horizontal plane. may be provided.
なお、前記実施例では測定点P1，P2のそれぞ
れに第１０図に示す検出装置２２を設置したもの
について述べたが、かならずしもこれに限定され
るものではなく、例えば第１２図に示すように１
対の検出コイル３７１，３７２を有する検出位置
３２を使用すれば上記各検出コイル３７１，３７
２でP1点、P2点の磁界の方向を同時に計測する
ことができ作業能率の向上が図れる。前記検出装
置３２は所定の間隔をあけて対向立設された支持
部３３１，３３２を有する治具３４の上記支持部
３３１，３３２の上方および下方に軸受３５１，
３５２，３５３，３５４を設け、軸受３５１，３
５２間に円柱状の保持機構３６１を回転自在に設
けるとともに軸受３５３，３５４間に円柱状の保
持機構３６２を回転自在に設けている。前記各保
持機構３６１，３６２に前記検出コイル３７１，
３７２をそれぞれ取付けている。そして前記検出
コイル３７１，３７２から発生する誘導起電力信
号を信号増幅器３８を介して演算処理装置３９に
入力している。前記各保持機構３６１，３６２は
それぞれ歯車４０，４１を介して駆動装置４２に
連続され、前記検出コイル３７１，３７２を駆動
装置４２によつて同相で同一面内で回転するよう
にしている。検出コイル３７１，３７２の回転角
は駆動装置４２とジヨイント機構４３を介して接
続されている高精度角度計４４によつて測定され
前記演算処理装置３９に入力される。このような
検出装置３２を使用すれば同一水平面内あるいは
同一垂直面内の２点において同時に測定ができ、
作業能率が約２倍に改善できる。 In the above embodiment, the detection device 22 shown in FIG. 10 was installed at each of the measurement points P 1 and P 2 , but the detection device 22 shown in FIG. 10 is not necessarily limited to this. to 1
If the detection position 32 having a pair of detection coils 371, 372 is used, each of the detection coils 371, 37
2, the direction of the magnetic field at point P1 and point P2 can be measured simultaneously, improving work efficiency. The detection device 32 includes bearings 351, which are disposed above and below the support portions 331, 332 of the jig 34, which has support portions 331, 332 that are erected facing each other at a predetermined interval.
352, 353, 354 are provided, and bearings 351, 3 are provided.
A cylindrical holding mechanism 361 is rotatably provided between the bearings 353 and 354, and a cylindrical holding mechanism 362 is rotatably provided between the bearings 353 and 354. The detection coil 371,
372 are installed respectively. The induced electromotive force signals generated from the detection coils 371 and 372 are input to the arithmetic processing unit 39 via the signal amplifier 38. The holding mechanisms 361 and 362 are connected to a drive device 42 via gears 40 and 41, respectively, and the detection coils 371 and 372 are rotated by the drive device 42 in the same phase and within the same plane. The rotation angles of the detection coils 371 and 372 are measured by a high-precision angle meter 44 connected to a drive device 42 via a joint mechanism 43, and are input to the arithmetic processing device 39. If such a detection device 32 is used, it is possible to simultaneously measure two points within the same horizontal plane or the same vertical plane.
Work efficiency can be approximately doubled.
また、前記実施例においては１本の帰路電流用
線路１４を設け、その線路１４を少しずつずらせ
る方式をとつたがかならずしもこれに限定される
ものではなく例えば第１３図に示すようにｎ本の
線路１４−１，１４−２，………１４−ｎを距離
ｔずつ離して配設し、その各線路の両端を留具４
５，４６によつて１束に束ね、その束ねた一方を
立上げ線１６に接続し、他方を切換装置４７を介
して送信装置１７に接続してもよい。こうするこ
とによつて計測の都度線路の配設位置をずらせる
ような面倒な作業がなく切換装置４７を操作すれ
ばよくさらに作業性を向上することができる。 Further, in the embodiment described above, one return current line 14 was provided and the line 14 was shifted little by little, but the present invention is not limited to this. For example, as shown in FIG. The tracks 14-1, 14-2, ......14-n are arranged at a distance t apart, and both ends of each track are connected to the fasteners 4.
5 and 46, one end of the bundle may be connected to the rising line 16, and the other end may be connected to the transmitting device 17 via the switching device 47. By doing so, there is no need for troublesome work such as shifting the arrangement position of the line every time a measurement is made, and all that is required is to operate the switching device 47, and the workability can be further improved.
以上詳述したようにこの発明によれば、地下に
埋設された導体と略平行するように帰路電流用線
路を地表上に配設して導体及び線路を対向辺とす
る方形状の閉ループを形成し、この閉ループに交
流電流を通流させて交番磁界を発生させ、導体に
よる磁界と線路による磁界との合成磁界の方向を
導体の片側に位置する地表上の２点において計測
し、導体が線路の真下にあると仮定して合成磁界
の方向の計測値より導体の埋設深さを測定し、こ
の合成磁界の方向の計測と埋設深さの測定とを線
路の配設位置を変化させて複数回行い、このとき
の２点における埋設深さの各測定値が一致する値
の線路の位置及び導体の埋設深さの計測値から導
体の地下埋設位置を検出するようにしているの
で、導体の地下埋設位置を高精度に測定すること
ができ、しかも測定に必要なスペースを少なくす
ることができて実用性を向上できる地下埋設導体
の埋設位置検出方法を提供できるものである。 As detailed above, according to the present invention, the return current line is arranged on the ground surface so as to be substantially parallel to the conductor buried underground, thereby forming a rectangular closed loop with the conductor and the line as opposite sides. Then, an alternating current is passed through this closed loop to generate an alternating magnetic field, and the direction of the composite magnetic field of the magnetic field due to the conductor and the magnetic field due to the line is measured at two points on the earth's surface located on one side of the conductor. The buried depth of the conductor is measured from the measured value of the direction of the composite magnetic field, assuming that the conductor is directly under The buried position of the conductor is detected from the measured value of the buried depth of the conductor and the position of the line where the measured values of the buried depth at the two points match. An object of the present invention is to provide a method for detecting the buried position of an underground conductor, which can measure the underground buried position with high precision, and can also reduce the space required for measurement, thereby improving practicality.
第１図は従来例を示す概略構成図、第２図〜第
７図はこの発明の原理を説明するためのもので、
第２図は基本原理を示す図、第３図は斜視図、第
４図は誤差発生を説明するための図、第５図は第
４図の場合の誤差結果を示すグラフ、第６図は検
出原理を説明するための概略図、第７図は第６図
による検出結果の一例を示すグラフ、第８図〜第
１１図はこの発明の実施例を示すもので、第８図
は斜視図、第９図は送信装置を示すブロツク図、
第１０図は検出装置の概略構成図、第１１図は実
験例を示す概略図、第１２図はこの発明の他の実
施例を示す検出装置の概略構成図、第１３図はこ
の発明の他の実施例を示す部分概略図である。
１１……埋設導体、１４……帰路電流用線路、
１７……送信装置、２２……検出装置。
FIG. 1 is a schematic configuration diagram showing a conventional example, and FIGS. 2 to 7 are for explaining the principle of this invention.
Figure 2 is a diagram showing the basic principle, Figure 3 is a perspective view, Figure 4 is a diagram to explain error occurrence, Figure 5 is a graph showing error results in the case of Figure 4, and Figure 6 is A schematic diagram for explaining the detection principle, FIG. 7 is a graph showing an example of the detection result according to FIG. 6, FIGS. 8 to 11 show examples of the present invention, and FIG. 8 is a perspective view. , FIG. 9 is a block diagram showing the transmitting device,
FIG. 10 is a schematic configuration diagram of a detection device, FIG. 11 is a schematic diagram showing an experimental example, FIG. 12 is a schematic configuration diagram of a detection device showing another embodiment of the present invention, and FIG. 13 is a schematic diagram of a detection device other than this invention. FIG. 2 is a partial schematic diagram showing an embodiment of the invention. 11... Buried conductor, 14... Return current line,
17... Transmitting device, 22... Detecting device.
Claims (1)
路電流用線路を地表上に配設して上記導体及び線
路を対向辺とする方形状の閉ループを形成し、こ
の閉ループに交流電流を通流させて交番磁界を発
生させ、上記導体による磁界と上記線路による磁
界との合成磁界の方向を上記導体の片側に位置す
る前記地表上の２点において計測し、上記導体が
上記線路の真下にあると仮定して上記合成磁界の
方向の計測値より上記導体の埋設深さを測定し、
この合成磁界の方向の計測と上記埋設深さの測定
とを上記線路の配設位置を変化させて複数回行
い、このときの上記２点における上記埋設深さの
各測定値が一致する値の上記線路の位置及び上記
導体の埋設深さの計測値から上記導体の地下埋設
位置を検出するようにしたことを特徴とする地下
埋設導体の埋設位置検出方法。1 A return current line is laid out on the ground surface so as to be approximately parallel to the conductor buried underground to form a rectangular closed loop with the conductor and line as opposing sides, and an alternating current is passed through this closed loop. to generate an alternating magnetic field, and the direction of the composite magnetic field of the magnetic field by the conductor and the magnetic field by the line is measured at two points on the ground surface located on one side of the conductor, and the conductor is directly below the line. Assuming that, the buried depth of the conductor is measured from the measured value of the direction of the composite magnetic field,
The measurement of the direction of the composite magnetic field and the measurement of the buried depth are performed multiple times by changing the installation position of the line, and each measurement value of the buried depth at the two points at this time is the same value. A method for detecting a buried position of an underground conductor, characterized in that the underground position of the conductor is detected from measured values of the position of the line and the buried depth of the conductor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56086491A JPS57200802A (en) | 1981-06-05 | 1981-06-05 | Method for detecting buried position of underground buried conductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56086491A JPS57200802A (en) | 1981-06-05 | 1981-06-05 | Method for detecting buried position of underground buried conductor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57200802A JPS57200802A (en) | 1982-12-09 |
| JPS642227B2 true JPS642227B2 (en) | 1989-01-17 |
Family
ID=13888449
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56086491A Granted JPS57200802A (en) | 1981-06-05 | 1981-06-05 | Method for detecting buried position of underground buried conductor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57200802A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2608618B2 (en) * | 1990-05-09 | 1997-05-07 | 株式会社フジクラ | Metal long object buried position measuring device |
| JP6167530B2 (en) * | 2013-01-23 | 2017-07-26 | 日立金属株式会社 | Measuring device and method for manufacturing differential signal transmission cable |
| CN103837900B (en) * | 2013-09-09 | 2016-08-31 | 北京鼎臣超导科技有限公司 | A kind of buried cable localization method based on Vector Magnetic Field detection and device |
| JP6292998B2 (en) * | 2014-06-24 | 2018-03-14 | 日鉄住金パイプライン＆エンジニアリング株式会社 | Pipe locating method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57190284A (en) * | 1981-05-20 | 1982-11-22 | Nippon Kokan Kk <Nkk> | Detection of buried position of underground conductor |
-
1981
- 1981-06-05 JP JP56086491A patent/JPS57200802A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57200802A (en) | 1982-12-09 |
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