JPH069746B2 - Seam position detector - Google Patents
Seam position detectorInfo
- Publication number
- JPH069746B2 JPH069746B2 JP1142386A JP14238689A JPH069746B2 JP H069746 B2 JPH069746 B2 JP H069746B2 JP 1142386 A JP1142386 A JP 1142386A JP 14238689 A JP14238689 A JP 14238689A JP H069746 B2 JPH069746 B2 JP H069746B2
- Authority
- JP
- Japan
- Prior art keywords
- seam
- subject
- magnetic field
- magnetic
- support member
- 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 - Lifetime
Links
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- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
Description
【発明の詳細な説明】 <産業上の利用分野> 本発明は、熔接縫合線(シーム線)部をもつ電縫鋼管又
は鋼板のシーム位置を検出するシーム位置検出装置に関
する。Description: TECHNICAL FIELD The present invention relates to a seam position detecting device for detecting a seam position of an electric resistance welded steel pipe or a steel plate having a welded seam (seam line) portion.
<従来の技術> 電縫鋼管等において、そのシーム部、特にホワイトライ
ンと呼ばれるシーム線の位置を検出することは、その製
品の品質検査等にて必要事項である。特に超音波探傷や
ポストアニーリング(局部熱処理)等において、0.1
mm単位によるホワイトライン或はシーム部の正確な位置
検出が必要となる。<Prior Art> In an electric resistance welded steel pipe or the like, detecting the position of a seam portion, particularly a seam line called a white line is a necessary item in quality inspection of the product. Especially in ultrasonic flaw detection and post annealing (local heat treatment), 0.1
Accurate position detection of the white line or seam in mm is required.
シーム部はそれが熔接されてから、特にその部分を他の
部分と機械的な程度差や外観的な差を生じないよう加工
された場合には、簡単にシーム位置を正確に検出するこ
とは困難である。このため、従来はシーム位置の検出方
法として、光学的な検出法、電気抵抗による検出法、超
音波による検出法、磁気的検出法等が提案されている。
しかし、光学的な検出法では、シームの周辺部が機械的
加工による変色が少ないことがあり得ること、電気抵抗
による検出法では電気抵抗値変化がシーム部分のみと限
らぬこと、超音波による検出法では、超音波特性変化が
シーム位置にのみ限らないこと、磁気的検出法では磁力
線密度変化がシーム部分以外にも生ずること等から、
0.1mm単位でシーム位置を測定することは困難であっ
た。It is not easy to accurately detect the seam position after the seam is welded, especially when that part is machined so as not to cause a mechanical degree difference or appearance difference from other parts. Have difficulty. Therefore, conventionally, as a seam position detecting method, an optical detecting method, an electric resistance detecting method, an ultrasonic detecting method, a magnetic detecting method, and the like have been proposed.
However, in the optical detection method, the peripheral part of the seam may be less discolored due to mechanical processing.In the detection method by electric resistance, the electric resistance value change is not limited to only the seam part. In the method, the change in ultrasonic characteristics is not limited to the seam position, and in the magnetic detection method, the change in the magnetic force line density occurs not only in the seam portion, but
It was difficult to measure the seam position in units of 0.1 mm.
<発明が解決しようとする課題> 一般に、被検体である鋼管や鋼板の材料である鋼鉄は、
炭素とその他の各種元素を微量であるが含んでいる。例
えば、鋼管のシーム部はこれが製作されるとき、両側よ
り突当て面を電流等により高温熔解して合体し冷却固化
される。このとき鉄の熔解温度を越えるのは突当て面、
即ちシームであるが、その際シーム付近に存在する炭素
は酸化してガスとなり脱出する。又、冷却の遅れるのは
シーム部分であるので鉄より熔解温度の低い元素は偏折
してシーム部では減少する現象となる。このようなシー
ム部が被検体にある場合、磁力線を当てるとシーム部分
の周辺では磁力線集中が生じ、その磁力線分布が独特の
形状を呈することが発見された。本発明はシーム部での
磁気的特性がその他の部分に対して独特な変化をするこ
とに着目し、安定正確にシーム位置を検出する装置を提
供しようとするものである。<Problems to be Solved by the Invention> In general, steel that is a material of a steel pipe or a steel plate that is a subject is
It contains a small amount of carbon and various other elements. For example, when the seam portion of the steel pipe is manufactured, the abutting surfaces are melted at high temperature from both sides by an electric current or the like to be united and cooled and solidified. At this time, it is the abutting surface that exceeds the melting temperature of iron,
That is, it is a seam, but at that time, carbon existing in the vicinity of the seam is oxidized and becomes a gas to escape. Further, since the cooling is delayed at the seam portion, an element having a melting temperature lower than that of iron is unevenly distributed and the phenomenon is reduced at the seam portion. It has been discovered that when such a seam portion is present in the subject, when the magnetic force lines are applied, the magnetic force lines concentrate around the seam portion and the magnetic force line distribution has a unique shape. The present invention focuses on the fact that the magnetic characteristics at the seam portion change uniquely with respect to the other portions, and aims to provide a device for detecting the seam position stably and accurately.
<課題を解決するための手段> 本発明はシーム部をもつ被検体の表面から隔てられた位
置に置いたほぼ分布一様な密度の磁力線源の一方の極の
上面に透磁率の高い材料からなり、左右端を下方に折り
曲げた折り曲げ部を有する支持部材を設け、前記磁力線
源の他方の極の下面に非磁性体からなる支持体を設け、
該支持体の下面に被検体の表面に接触又は近接して磁力
線密度検出素子を取付け、該検出素子をシーム線に直角
の方向に移動させ磁力線密度の変化を検出すると共に、
該検出出力を電気的判定回路に入力し、シーム位置を検
出しようとするものである。<Means for Solving the Problems> The present invention uses a material having a high magnetic permeability on the upper surface of one pole of a magnetic field source having a substantially uniform density placed at a position separated from the surface of a subject having a seam portion. A support member having a bent portion in which the left and right ends are bent downward, and a support made of a non-magnetic material is provided on the lower surface of the other pole of the magnetic force source.
A magnetic field line density detection element is attached to the lower surface of the support in contact with or close to the surface of the subject, and the change in magnetic field line density is detected by moving the detection element in the direction perpendicular to the seam line,
The detection output is input to an electrical determination circuit to detect the seam position.
また、本発明は磁力線源の被検体の表面の距離は、磁力
線源の幅と同等か、若しくはこれより大となるよう構成
したものであり、更に、磁力線源の側面と、支持部材の
折り曲げ部の間隔は、磁力線源の極面と被検体の表面と
の距離より大となるようにし、また、支持部材の左右長
さは、被検査体の半径より大で、且つ支持部材の厚さは
少なくとも被検体の厚さ以上としたものである。Further, the present invention is configured such that the distance of the surface of the subject of the magnetic field source is equal to or larger than the width of the magnetic field source, and further, the side surface of the magnetic field source and the bent portion of the supporting member. Is larger than the distance between the pole surface of the magnetic field source and the surface of the subject, and the left and right lengths of the support member are larger than the radius of the object to be inspected and the thickness of the support member is At least the thickness of the subject is set.
<作 用> 本発明はシーム位置を検出するに、検出部を固定し被検
体を回転させるか、或は被検体を固定し検出部を同軸に
移動させるかして、磁力線密度検出器がシーム線の上部
を通過するようにして磁力線源より磁力線を当てると、
シーム付近での電気的出力が他の部分と相違した独特の
変化をなし、これを検出し電気的判定回路に入力するこ
とによりシーム位置が正確に検出できる。<Operation> To detect the seam position, the magnetic field line density detector determines whether the seam position is fixed by rotating the subject and rotating the subject, or by fixing the subject and moving the detector coaxially. When applying a magnetic force line from the magnetic force source so that it passes through the upper part of the line,
The electrical output near the seam makes a unique change that is different from other parts, and by detecting this and inputting it to the electrical determination circuit, the seam position can be accurately detected.
<実施例> 以下、本発明の実施例を図示の図面に従って説明すれば
次の通りである。<Example> The following will describe an example of the present invention with reference to the accompanying drawings.
第1図は本発明の概略的構成を示すもので、1は検出
部、2は検出部の出力によりシーム位置を正確に判定す
る電子回路、3は被検体である電縫鋼管の断面を示し、
4はシーム位置を示すものである。FIG. 1 shows a schematic configuration of the present invention. Reference numeral 1 is a detection unit, 2 is an electronic circuit for accurately determining a seam position based on the output of the detection unit, and 3 is a cross section of an electric resistance welded steel pipe as a subject. ,
Reference numeral 4 indicates a seam position.
検出部1の詳細は第2図に示され、磁力線源である幅広
の永久磁石5の一方の極(図示ではN極)の上面に透磁
率の高い材料(例えば電気鉄)よりなる直線状の支持部
材6が左右端を下方に折曲げた折曲げ部7を備えて固定
され、又他方の極(図示ではS極)の下面には非磁性体
よりなる支持体8を介してホール素子からなる磁力線密
度検出素子9が被検体3の表面に接触又は近接して設け
られ、これらの検出部1は図示しないが被検体3をまた
ぐようにして支持され、場合により支持体1は被検体3
の周りを回転若しくは移動する機構を備える。これらの
機構は公知の手段で実施できるものであり、本発明では
特に限定しない。The details of the detection unit 1 are shown in FIG. 2, and a linear shape made of a material having high magnetic permeability (for example, electric iron) is formed on the upper surface of one pole (N pole in the drawing) of the wide permanent magnet 5 which is a magnetic field line source. The support member 6 is fixed by being provided with a bent portion 7 in which the left and right ends are bent downward, and the Hall element is connected to the lower surface of the other pole (S pole in the figure) through a support body 8 made of a non-magnetic material. The magnetic field line density detection element 9 is provided in contact with or close to the surface of the subject 3, and these detection units 1 are supported so as to straddle the subject 3 (not shown).
It has a mechanism to rotate or move around. These mechanisms can be implemented by known means and are not particularly limited in the present invention.
次に検出部1において、被検体3の表面の磁力線密度分
布が永久磁石5に拘束されず変化し得るためには、永久
磁石5の極面と被検体3の表面の距離Lは永久磁石5の
幅Sに対して等しいか、又はこれより大な程度であるこ
とが望ましい。又、被検体3を通過しない漏洩磁力線を
減少するために、永久磁石5の側面5′と支持部材6の
折曲げ部との間隔Rは前記した永久磁石5の極面と被検
体3の表面との距離Lより大であるのが望ましい。Next, in the detection unit 1, in order that the magnetic field line density distribution on the surface of the subject 3 may change without being constrained by the permanent magnet 5, the distance L between the pole face of the permanent magnet 5 and the surface of the subject 3 is set to the permanent magnet 5. It is desirable that the width is equal to or larger than the width S of the above. Further, in order to reduce the leakage magnetic field lines that do not pass through the subject 3, the distance R between the side surface 5 ′ of the permanent magnet 5 and the bent portion of the support member 6 is set to the above-mentioned polar surface of the permanent magnet 5 and the surface of the subject 3. It is desirable that the distance L be larger than the distance L.
又、被検体3に広く磁力線10を供給し、且つ磁路が被検
体3より磁気減衰を小とするため、支持部材6の左右長
(2×w)は被検体3の半径より大であり、支持部材6
の厚さはTは少なくとも被検体3の厚さ以上であること
が望ましい。又、支持部材6は直線状でなくても第3図
の図示の如く、湾曲した形状であっても磁路としては問
題がなく、更に磁気的減衰を減ずるよう支持部材6の両
端の折曲げ部7を先端が被検体3の周面に沿った形状と
することもできる。Further, since the magnetic field lines 10 are widely supplied to the subject 3 and the magnetic path makes the magnetic attenuation smaller than that of the subject 3, the lateral length (2 × w) of the support member 6 is larger than the radius of the subject 3. , Support member 6
As for the thickness T, it is desirable that T is at least not less than the thickness of the subject 3. Further, even if the support member 6 is not linear, as shown in FIG. 3, even if the support member 6 has a curved shape, there is no problem as a magnetic path, and bending of both ends of the support member 6 is performed to further reduce magnetic attenuation. The tip of the portion 7 may be shaped so as to follow the peripheral surface of the subject 3.
次に作用を説明すると、第2図の状態において、仮りに
シーム4が被検体3にないとすると、永久磁石5の発生
する磁力線10は磁路である支持部材6、折曲げ部7、空
気、被検体3を通過し、第4図のように分布する。ここ
で、磁力線源である永久磁石5の表面が幅広く、且つ被
検体3と隔てられているので、支持体8の先端の磁力線
密度検出素子9の前後において該検出素子9を通過する
磁力線密度は特に集中しない。更に、被検体3の内部の
原因により検出素子9の表面で磁力線10が集中しようと
することに対して特に拘束がない。Next, the operation will be described. In the state of FIG. 2, assuming that the seam 4 is not present in the subject 3, the magnetic force lines 10 generated by the permanent magnet 5 are the magnetic flux, the supporting member 6, the bent portion 7, and the air. , Passes through the subject 3 and is distributed as shown in FIG. Here, since the surface of the permanent magnet 5 which is the magnetic field line source is wide and is separated from the subject 3, the magnetic field line density passing through the detection element 9 before and after the magnetic field line density detection element 9 at the tip of the support 8 is I don't concentrate. Further, there is no particular restriction on the concentration of the magnetic force lines 10 on the surface of the detection element 9 due to the inside of the subject 3.
又、測定時にシーム4部が第2図で符号4にて示す位置
にあると、その部分の周辺では磁力線集中が生じ、その
磁力線密度分布は第5図に示す富士山型の形状を呈す
る。第5図に於て、縦軸は透磁率、横軸はシーム線に直
角方向の寸法を示す。又、第5図の符号Mで示す陥没部
はシーム位置、Hはシーム形成時に熔解され高温になっ
た熱影響部の範囲を示す。Further, when the seam 4 portion is located at the position indicated by reference numeral 4 in FIG. 2 during the measurement, the magnetic force line concentration occurs around the portion, and the magnetic force line density distribution has the shape of Mt. Fuji shown in FIG. In FIG. 5, the vertical axis represents the magnetic permeability, and the horizontal axis represents the dimension perpendicular to the seam line. Further, the depressed portion indicated by the symbol M in FIG. 5 indicates the seam position, and H indicates the range of the heat-affected zone which has been melted to a high temperature during seam formation.
いま、第2図の状態において、検出部1は固定し、被検
体3を図上左方向に回転させるか、又は被検体3を固定
して検出部1と被検体3と同軸に右方向に移動させ、磁
力線密度検出素子9がシーム線4の上部を通過するよう
にする。測定においてはこの回転、移動により検出素子
9はそれを貫通する磁力線密度を電気的に検出するか
ら、その回転又は移動に伴なうシーム4付近での電気的
出力は前述した第5図の波形となる。Now, in the state of FIG. 2, the detection unit 1 is fixed and the subject 3 is rotated leftward in the figure, or the subject 3 is fixed and the detection unit 1 and the subject 3 are coaxially moved rightward. It is moved so that the magnetic force line density detection element 9 passes above the seam line 4. In the measurement, this rotation and movement causes the detection element 9 to electrically detect the magnetic flux density penetrating therethrough. Therefore, the electrical output near the seam 4 accompanying the rotation or movement is the waveform shown in FIG. Becomes
かくして、磁力線密度検出素子9が検出する電気的出力
はシーム4以外の場所で常に一定であるとは言えず、被
検体3である鋼管材料内部での透磁率の部分的変動、鋼
材加工の時発生する部分的帯磁、周辺での磁性体の近
接、或いは局部的な加工傷等で出力変化があり得る。Thus, it cannot be said that the electrical output detected by the magnetic force line density detection element 9 is always constant at a place other than the seam 4, and the partial change of the magnetic permeability inside the steel pipe material which is the subject 3 is caused when the steel material is processed. There may be a change in output due to partial magnetization generated, proximity of magnetic material in the periphery, or local processing scratches.
ここで、機械的駆動装置により検出部1と被検体3を相
対的に連続回転させ、被検体3の全周にわたる検出素子
9の電気的出力の例を第6図に示す。第6図において、
符号11で示す波形部分はシーム部における出力である
が、このシーム部波形11はその他の場合における電気的
出力波形とその形態特徴に大きな相違があることが判明
する。即ち、第1の特徴は、シーム部波形11における1
振幅Aは最大であり、その他の場所においてはその電気
的出力は大であっても1振幅としてはシーム部波形11よ
りいずれも小さい。第2の特徴は、シーム部波形11はシ
ーム部の局所で発生するのでその周辺から急激に拡大変
化し、その傾斜角は大きい。第3の特徴は、シーム部波
形11はシーム4線をほぼ中心として左右対照的である
が、その他の場所の波形は不定である。従って、被検体
3の全周にわたり検出素子9の出力を取出した結果で、
上記した第1、第2、第3の特徴を合わせもつ場所を見
出すことで、シーム位置が確定される。Here, FIG. 6 shows an example of the electrical output of the detection element 9 over the entire circumference of the subject 3 when the detection unit 1 and the subject 3 are relatively continuously rotated by the mechanical drive device. In FIG.
The waveform portion indicated by reference numeral 11 is the output at the seam portion, but it is found that this seam portion waveform 11 has a great difference in the morphological characteristics from the electrical output waveform in other cases. That is, the first feature is that 1 in the seam waveform 11
The amplitude A is the maximum, and the electric output is large in other places, but is smaller than the seam waveform 11 as one amplitude. The second characteristic is that the seam portion waveform 11 is generated locally at the seam portion, so that the seam portion waveform abruptly expands and changes from its periphery, and its inclination angle is large. The third feature is that the seam portion waveform 11 is symmetrical with the seam 4 line as the center, but the waveforms at other locations are indefinite. Therefore, as a result of extracting the output of the detection element 9 over the entire circumference of the subject 3,
The seam position is determined by finding a place having the above-mentioned first, second, and third features together.
尚、被検体3の全周の測定をし、シーム部波形11を予備
的に検出記憶した上で、次に記憶したシーム部波形11の
場所を改めて測定し、シーム位置を高精度で指定しても
よい。このように、1回全周の測定をした後、シーム部
波形11部分のみの測定をし直す場合に、検出部1の本体
はほぼシーム部波形11の位置に固定し、磁力線密度検出
素子9のみを微少寸法だけ左右に機械的に揺動させる方
式によてもよい。In addition, after measuring the entire circumference of the subject 3 and detecting and storing the seam portion waveform 11 in advance, the location of the next stored seam portion waveform 11 is measured again and the seam position is designated with high accuracy. May be. As described above, when the seam waveform 11 is measured again after the entire circumference is measured once, the main body of the detection unit 1 is fixed substantially at the seam waveform 11, and the magnetic field line density detection element 9 is used. It is also possible to use a method in which the chisel is mechanically oscillated to the right and left by a minute dimension.
以上のように被検体3の全周にわたり、磁力線密度検出
素子9の電気的出力を取り出して、シーム部波形11にお
けるシーム位置を検出するのに第1図に示す電子回路2
が用いられる。この電子回路2の動作は第7図に示す
が、これは判定の動作を各個に区分して示したもので、
この各動作の順番は限定されない。又場合により不作
用、除外できるものもある。In order to detect the seam position in the seam portion waveform 11 by taking out the electrical output of the magnetic force line density detection element 9 over the entire circumference of the subject 3 as described above, the electronic circuit 2 shown in FIG.
Is used. The operation of the electronic circuit 2 is shown in FIG. 7, which shows the judgment operation divided into individual parts.
The order of each operation is not limited. In some cases, it may be ineffective or may be excluded.
このようにして前記したシーム部波形11の第1、第2、
第3の特徴を合せもつ波形11を見出した後、その中央部
分で生ずる減少の最低値の位置Mを検出すれば、ここが
シーム位置を示すことになる。被検体3の材料、種類に
よっては中央部分の減少がなく、最高値がシーム位置を
示すことがあるが、これらは被検体3の全周の測定の
際、どのような判定をすればシーム位置であるかの判定
機能をもたせればよい。又、波形の両側の最大値Hの位
置から熱影響部の位置と幅を知ることができる。In this way, the first, second, and
After finding the waveform 11 having the third characteristic, if the position M of the minimum value of the decrease occurring in the central portion is detected, this indicates the seam position. The maximum value may indicate the seam position depending on the material and type of the object 3 to be measured, but the maximum value may indicate the seam position. It suffices to have a function for determining whether or not Further, the position and width of the heat-affected zone can be known from the positions of the maximum value H on both sides of the waveform.
かくして、検出したシーム位置を記憶し、表示し、或い
は駆動部分に指令してその位置に停止させる等は前記の
判定検出回路の動作と共に、電子回路、コンピュータソ
フトにて容易に具体化することができる。Thus, the storage of the detected seam position, display, or command to the driving portion to stop at that position can be easily embodied by an electronic circuit or computer software together with the operation of the judgment detecting circuit. it can.
<発明の効果> 上述のように本発明ではシーム部をもつ被検体の表面か
ら隔てられた位置に置いたほぼ分布一様な密度の磁力線
源の一方の極の上面に透磁率の高い材料からなり、左右
端を下方に折り曲げた支持部材を設け、磁力線源より磁
力線を被検体に当て、該磁力線の存在する被検体の表面
又は表面に近接して非磁性体からなる支持体の下面に取
付けた磁力線密度検出素子を、シーム線に直角方向に移
動し、磁力線密度の変化を検出し、電気的判定回路に入
力してシーム位置を検出するようにしたことで、シーム
の正確な位置を確実に検出することができる。尚、磁力
線源の支持部材に折曲げ部を設けたことで、被検体に広
く磁力線を供給することができ、正確なシーム位置の検
出をすることができる。<Effects of the Invention> As described above, according to the present invention, a material having a high magnetic permeability is formed on the upper surface of one pole of the magnetic field source having a substantially uniform density placed at a position separated from the surface of the subject having the seam portion. Therefore, a supporting member whose right and left ends are bent downward is provided, and the magnetic force line is applied to the subject from the magnetic force source, and is attached to the surface of the subject where the magnetic force line exists or close to the surface and the lower surface of the non-magnetic support. The magnetic field line density detection element is moved in the direction perpendicular to the seam line to detect changes in the magnetic field line density and input it to the electrical judgment circuit to detect the seam position, ensuring accurate seam position. Can be detected. By providing the bent portion on the support member of the magnetic field source, the magnetic field can be widely supplied to the subject, and the seam position can be accurately detected.
更に、磁力線源である永久磁石の極面と被検体の表面の
距離を永久磁石の幅と同等か、それ以上の幅とすること
により、被検体の表面の磁力線密度分布が永久磁石に拘
束されずに変化させることができる。Furthermore, by setting the distance between the polar surface of the permanent magnet, which is the magnetic field source, and the surface of the subject to be equal to or greater than the width of the permanent magnet, the magnetic flux density distribution on the surface of the subject is constrained by the permanent magnet. Can be changed without.
また、磁力線源である永久磁石の側面と支持部材の折曲
げ部との間隔を永久磁石の極面と被検体の表面との距離
より大としたことにより、被検体を通過しない漏洩磁力
線を減少させることができる。In addition, the distance between the side surface of the permanent magnet, which is the source of magnetic force, and the bent portion of the support member is set to be larger than the distance between the pole surface of the permanent magnet and the surface of the subject, thereby reducing leakage magnetic field lines that do not pass through the subject. Can be made.
また、支持部材の左右長さを被検体の半径より大とし、
且つ支持部材の厚さを少なくとも被検体の厚さ以上とす
ることで、被検体に広く磁力線を供給し得、磁気減衰を
小さくすることができる。In addition, the left and right length of the support member is larger than the radius of the subject,
In addition, by setting the thickness of the support member to be at least the thickness of the subject, magnetic lines of force can be widely supplied to the subject, and magnetic attenuation can be reduced.
しかも、本発明はシーム部での磁力線密度分布が独特の
富士山型波形となって検出でき、この波形は他の場所で
の波形と区別できる特徴をもったものであることから、
電縫鋼管等の製作時に生ずる熱影響部の位置と幅、更に
はシームの正しい位置を検出することができる。Moreover, in the present invention, the magnetic field line density distribution at the seam can be detected as a unique Mt.Fuji waveform, and this waveform has a feature that it can be distinguished from waveforms at other locations.
It is possible to detect the position and width of the heat-affected zone, which is generated during the production of the electric resistance welded steel pipe, and the correct position of the seam.
図面は本発明の実施例を示すもので、第1図は本発明の
概略した構成を示す説明図、第2図は検出部の拡大した
正面図、第3図は検出部の他の実施例を示す正面図、第
4図は磁力線分布を示す説明図、第5図はシーム部波形
を示す説明図、第6図は被検体の全周にわたる電気的出
力の波形を示す説明図、第7図は電子回路の動作を示す
説明図である。 1...検出部 2...電子回路 3...被検体 4...シーム位置 5...永久磁石 6...支持部材 8...支持体 9...磁力線密度検出素子 11...シーム部波形 12、13...永久磁石。The drawings show an embodiment of the present invention. FIG. 1 is an explanatory view showing a schematic configuration of the present invention, FIG. 2 is an enlarged front view of a detecting portion, and FIG. 3 is another embodiment of the detecting portion. FIG. 4 is an explanatory diagram showing a magnetic field line distribution, FIG. 5 is an explanatory diagram showing a seam waveform, and FIG. 6 is an explanatory diagram showing an electric output waveform over the entire circumference of the subject, The figure is an explanatory view showing the operation of the electronic circuit. 1. . . Detector 2. . . Electronic circuit 3. . . Subject 4. . . Seam position 5. . . Permanent magnet 6. . . Support member 8. . . Support 9. . . Magnetic field density detector 11. . . Seam waveform 12,13. . . permanent magnet.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭55−14145(JP,A) ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-55-14145 (JP, A)
Claims (4)
た位置に置いたほぼ分布一様な密度の磁力線源の一方の
極の上面に透磁率の高い材料からなり、左右端を下方に
折り曲げた折り曲げ部を有する支持部材を設け、前記磁
力線源の他方の極の下面に非磁性体からなる支持体を設
け、該支持体の下面に被検体の表面に接触又は近接して
磁力線密度検出素子を取付け、該検出素子をシーム線に
直角の方向に移動させ磁力線密度の変化を検出すると共
に、該検出出力を電気的判定回路に入力し、シーム位置
を検出することを特徴とするシーム位置検出装置。1. An upper surface of one pole of a magnetic field source having a substantially uniform distribution, which is placed at a position separated from the surface of a subject having a seam portion, is made of a material having high magnetic permeability, and its right and left ends are directed downward. A support member having a bent portion is provided, a support made of a non-magnetic material is provided on the lower surface of the other pole of the magnetic field source, and the magnetic field line density is detected by contacting or approaching the surface of the subject on the lower surface of the support. A seam position characterized by mounting an element, detecting the change in the magnetic force line density by moving the detection element in a direction perpendicular to the seam line, and inputting the detection output to an electrical determination circuit to detect the seam position. Detection device.
磁力線源の幅と同等か、若しくはこれより大となるよう
構成したことを特徴とする請求項1記載のシーム位置検
出装置。2. The distance between the polar surface of the magnetic field source and the surface of the subject is
The seam position detecting device according to claim 1, wherein the width is equal to or larger than the width of the magnetic field source.
の間隔は、磁力線源の極面と被検体の表面との距離より
大であることを特徴とする請求項1記載のシーム位置検
出装置。3. The seam position detection according to claim 1, wherein the distance between the side surface of the magnetic field source and the bent portion of the support member is larger than the distance between the polar surface of the magnetic field source and the surface of the subject. apparatus.
り大で、且つ支持部材の厚さは少なくとも被検査体の厚
さ以上であることを特徴とする請求項1記載のシーム位
置検出装置。4. The seam according to claim 1, wherein the lateral length of the support member is larger than the radius of the non-inspection body, and the thickness of the support member is at least the thickness of the inspection body or more. Position detection device.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1142386A JPH069746B2 (en) | 1989-06-05 | 1989-06-05 | Seam position detector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1142386A JPH069746B2 (en) | 1989-06-05 | 1989-06-05 | Seam position detector |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH038586A JPH038586A (en) | 1991-01-16 |
JPH069746B2 true JPH069746B2 (en) | 1994-02-09 |
Family
ID=15314158
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP1142386A Expired - Lifetime JPH069746B2 (en) | 1989-06-05 | 1989-06-05 | Seam position detector |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH069746B2 (en) |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5514145A (en) * | 1978-07-17 | 1980-01-31 | Nippon Kokan Kk <Nkk> | Weld seam center determining method |
-
1989
- 1989-06-05 JP JP1142386A patent/JPH069746B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPH038586A (en) | 1991-01-16 |
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