JPS6020708B2 - edge detector - Google Patents
edge detectorInfo
- Publication number
- JPS6020708B2 JPS6020708B2 JP54055127A JP5512779A JPS6020708B2 JP S6020708 B2 JPS6020708 B2 JP S6020708B2 JP 54055127 A JP54055127 A JP 54055127A JP 5512779 A JP5512779 A JP 5512779A JP S6020708 B2 JPS6020708 B2 JP S6020708B2
- Authority
- JP
- Japan
- Prior art keywords
- coil
- ferrite
- inductance
- edge
- detection coil
- 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
Landscapes
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
- Geophysics And Detection Of Objects (AREA)
Description
【発明の詳細な説明】
この発明は、渦電流の効果を利用した銅板等のエッジ検
出器に係り、特に温度、磁界等の外乱の影響を極度に軽
減する構造に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an edge detector such as a copper plate that utilizes the effect of eddy current, and particularly to a structure that extremely reduces the effects of disturbances such as temperature and magnetic fields.
従来渦電流の効果を利用した磁性金属のエッジ検出器は
し所定の巻数を施した検出コイルと基準コイルを夫々別
個の被巻回体に巻回して個々のケースに収納し、検出コ
イル側から一定距離に保持された鋼板エッジ部通過部に
向って磁遠を発し、鋼板のエッジ部と検出コイルの対向
面積によって変化する、渦電流に寄与する磁束の本数に
よって、検出コイルのィンダクタンスが、変化するわけ
であるが、このィンダクタンスと基準コイルからの定ィ
ンダクタンスとの位相差の変化を電圧変化、もしくは電
流変化に変換してその程度により鋼板のエッジ部の位置
を検出するものである。しかし該エッジ検出器において
例えば熱間圧延直後の厚板に対して内部欠陥を検出する
場合に採用するエッジ検出器は、雰囲気が高温、多湿、
干渉又は鋼板の残留磁界と条件が悪い。特に温度に対し
ては、前述の様な検出方法においては各コイルを巻回す
る被巻回体が別体なため材質も均一でなく従って該被巻
回体（フェライト）コイル、モールド材の温度による収
縮、膨張状態が異なり、そのまま出力特性に影響する度
合が異なる欠点があつナこ。この様な欠点は測定精度を
低下せしめ信頼性に乏しいものであった。Conventional edge detectors made of magnetic metal that utilize the effect of eddy currents have a detection coil and a reference coil with a predetermined number of turns each wound around separate bodies and housed in individual cases. The inductance of the detection coil is determined by the number of magnetic fluxes that contribute to the eddy current, which emit magnetic flux toward the steel plate edge passing portion held at a constant distance, and change depending on the facing area of the steel plate edge and the detection coil. However, the change in the phase difference between this inductance and the constant inductance from the reference coil is converted into a voltage change or current change, and the position of the edge of the steel plate is detected based on the degree of change. . However, the edge detector used when detecting internal defects in a thick plate immediately after hot rolling, for example, is difficult to use when the atmosphere is high temperature and humid.
Poor conditions with interference or residual magnetic field of steel plate. In particular, regarding temperature, in the above-mentioned detection method, the material to be wound around each coil is different, and the material is not uniform. The contraction and expansion states are different, and the disadvantage is that the degree to which it directly affects the output characteristics varies. Such drawbacks lowered measurement accuracy and resulted in poor reliability.
この発明はこの欠点を解消するためになされたもので、
検出精度を向上せしめ信頼性の高いエッジ検出器を提供
するものである。以下、この発明の実施例を第１図によ
り説明する。This invention was made to eliminate this drawback.
The present invention provides a highly reliable edge detector with improved detection accuracy. An embodiment of the invention will be described below with reference to FIG.
第１図はステンレス製の上端開放型の収納容器４内にセ
ットした検出器８の内部構造を示す。１は中央上・下部
夫々にコイル巻回用突条ｌａ，ｌｂを設けたＷ型のフェ
ライトであり、このフヱラィトーの上部の突条ｌａに検
出コイル２を巻回し、下部の突条ｌｂに基準コイル３を
巻回する。FIG. 1 shows the internal structure of a detector 8 set in a stainless steel container 4 with an open top. Reference numeral 1 is a W-shaped ferrite with protrusions la and lb for coil winding provided at the top and bottom of the center, respectively.A detection coil 2 is wound around the protrusion la at the top of this ferrite, and a reference is set around the protrusion lb at the bottom. Wind coil 3.
又突条ｌｂ側にはフェライト板１′を係合させて基準コ
イル３の磁路を形成させるとともに、このフェライト板
１′と前記変形フェライト１と各コイル２，３は各収納
容器４内に図示の如く防水性、断熱性、絶縁性、耐衝撃
性の充填材６を充填して位置固定セットする。第２図は
前記第１図の検出器８を鋼板７のエッジ通下部の直下に
設置したものであり鋼板のエッジの形状変形、もしくは
幅方向移動による検出器８上面直上の進入量変化を検出
コイル２からのィンダクタンスの変化と基準コイル３か
らの基準ィンダクタンスとによって検出するものである
。Further, a ferrite plate 1' is engaged with the projection lb side to form a magnetic path for the reference coil 3, and this ferrite plate 1', the deformed ferrite 1, and each coil 2, 3 are placed in each storage container 4. As shown in the figure, a waterproof, heat-insulating, insulating, and impact-resistant filler 6 is filled and set in a fixed position. Figure 2 shows the detector 8 shown in Figure 1 installed directly below the edge passage portion of the steel plate 7, and detects changes in the amount of penetration directly above the top surface of the detector 8 due to deformation of the edge of the steel plate or movement in the width direction. This is detected based on the change in inductance from the coil 2 and the reference inductance from the reference coil 3.
第３図は鋼板エッジの進入量とそれに伴う検出コイル２
と基準コイル３からのインダクタンスの位相差の出力特
性例を示す。前記検出コイル２と同定数に巻かれた基準
コイル３は鋼板７のエッジ検出に使用するための基準ィ
ンダクタンスを出力するものである。即ち、本例では鋼
板７のエッジが検出コイル２直上の中心に位置する特に
同コイル２から得るィンダクタンスと同等のィンダクタ
ンスを発信させ、これと検出コイル２からのィンダクタ
ンスと比較しての位相差の程度によって検出コイル２直
上への鋼板７のエッジの進入量を検出するものである。
而して検出器８の周囲の雰囲気の温度が変化した場合、
各コイル２，３導線の収縮膨張が当然有り、例えば基準
コイル３のコイル定数をＬｏ，、温度をＴ、温度係数を
ａ，、とすると、基準コイル定数功，はＬｏ，（１十ａ
，Ｔ）に変化する。この変化は検出コイル２においても
コイル定数をＬｏ２温度係数をａ２とすると、検出コイ
ル定数凶２はＬ妙（１十ａ２Ｔ）の変化がある。コイル
の配置上ａ，とａ２は多少異るがほぼａ，＝ａ２となり
両コイルのインピーダンス変化を電圧に変換にした後、
差動入力増幅に入れた場合、変化分の増減値は消去され
る出力が得られる。例として、基準コイル３と検出コイ
ル２を巻回するフェラィトーが一体構造となっている時
と、別構造となっている時との温度変化による各コイル
からのィンダクタンスの変化分の差を計算する。Figure 3 shows the intrusion amount of the steel plate edge and the accompanying detection coil 2.
An example of the output characteristic of the phase difference between the inductance and the reference coil 3 is shown. The detection coil 2 and the reference coil 3 wound in an identified number of coils output a reference inductance for use in edge detection of the steel plate 7. That is, in this example, the edge of the steel plate 7 is located at the center directly above the detection coil 2, and in particular, transmits an inductance equivalent to the inductance obtained from the coil 2, and compares this with the inductance from the detection coil 2. The amount of intrusion of the edge of the steel plate 7 directly above the detection coil 2 is detected based on the degree of phase difference.
Therefore, if the temperature of the atmosphere around the detector 8 changes,
Naturally, there is contraction and expansion of the conductors of each coil 2 and 3. For example, if the coil constant of the reference coil 3 is Lo, the temperature is T, and the temperature coefficient is a, the reference coil constant is Lo, (10a
, T). This change also occurs in the detection coil 2, where the coil constant is Lo2 and the temperature coefficient is a2, the detection coil constant 2 changes by L (10a2T). Due to the arrangement of the coils, a and a2 are slightly different, but approximately a, = a2, and after converting the impedance change of both coils into voltage,
When inputted into a differential input amplification, an output is obtained in which the increase/decrease value of the change is canceled. As an example, calculate the difference in the change in inductance from each coil due to temperature changes when the ferrite coils around the reference coil 3 and detection coil 2 have an integrated structure and when they have separate structures. do.
‘１｝ 一体構造の時
ィンダクタンスの変化分
＝い，（１十ａ，Ｔ）‐Ｌｏ２（１十ａ２Ｌ）＝Ｌ０，
一Ｌｏ２十Ｌｏ，ａ，Ｔ，一Ｌ０２ａ２Ｔ２＝い，‐Ｌ
ｏ２十Ｌｏ，ａ，Ｔ，‐凶２ａ２Ｔ，・・・・…“■（
一体構造のためＴ，＝Ｔ２）【２１ 別構造の時
ィンダクタンスの変化分
＝い，（１十ａ，Ｔ，）‐Ｌｏ２（１十ａ２Ｔ２）＝い
，‐Ｌｏ２十Ｌｏ，ａ，Ｔ，−山２をＴ２・・，．・・
…■（別構造のためＴ，‐羊Ｔ２）故に（１｝，ｔ２｝
のィンダクタンスの変化分の差は■‐■＝ゆ２ａ２Ｌ‐
Ｌｏ２ａ２Ｔ，：凶２ａ２（Ｌ‐Ｔ，）
………■■式より別構造の時が一体構造の時より山２ａ
２（Ｔ２一Ｔ，）だけ温度変化による影響をうけやすい
ことがわかる。'1} Change in inductance in integral structure = I, (10a, T) - Lo2 (10a2L) = L0,
1Lo20Lo,a,T,1L02a2T2=I,-L
o20Lo,a,T,-Ku2a2T,..."■(
Because of the integral structure, T, = T2) [21 Change in inductance of separate structure = I, (10a, T,) -Lo2 (10a2T2) = I, -Lo20Lo,a,T, - Mountain 2 is T2...・・・
...■ (T due to different structure, -sheep T2) Therefore (1}, t2}
The difference in inductance change is ■-■=yu2a2L-
Lo2a2T,: evil 2a2 (L-T,)
……■■Formula, when the structure is different, when it is an integral structure, it is mountain 2a.
2 (T2 - T,) is easily affected by temperature changes.
例へば、鉄鋼ラインではＴ，＝２５℃（常温）Ｌ土４０
０ｏｏである変化分は３７丸ｏ２ａ２となり無視できな
く、一体構造の時が非常に有利である。本発明はこの知
見にもとずし、てなされたものである。For example, on a steel line, T = 25℃ (room temperature) L soil 40
The variation of 0oo becomes 37 circles o2a2, which cannot be ignored, and the integral structure is very advantageous. The present invention has been made based on this knowledge.
即ち、検出コイル２と、基準コイル３を一体構造の変化
フェライト１の突条ｌａ，ｌｂに巻回することにより該
変形フェライト１に変化が起きても検出コイル２基準コ
イル３共同様な熱影響をうけるのでそのィンダクタソス
の変化分を消去することができる。又、磁界に対しても
一体構造の変形フェライト１を使用し基準コイル３側は
該フェライト板１′を配置して閉ループにし更にステン
レス等の非磁性材料で作成した該収納容器４内に密閉シ
ールドされているため、基準コイル３は底面、側面から
の外部磁界の影響はうけない。That is, by winding the detection coil 2 and the reference coil 3 around the protrusions la and lb of the deformed ferrite 1, which has an integral structure, even if a change occurs in the deformed ferrite 1, the detection coil 2 and the reference coil 3 will not be affected by the same heat. Therefore, the change in inductor sos can be eliminated. In addition, a deformed ferrite 1 with an integrated structure is used to withstand magnetic fields, and the ferrite plate 1' is placed on the reference coil 3 side to create a closed loop, and a hermetically sealed shield is placed in the storage container 4 made of a non-magnetic material such as stainless steel. Therefore, the reference coil 3 is not affected by external magnetic fields from the bottom or side surfaces.
故に測定精度を向上することができる。図中５は各コイ
ル２，３に接続する導線を被覆し、収納容器４の一側に
密閉シールド接続せしめたケーブルである。Therefore, measurement accuracy can be improved. In the figure, reference numeral 5 denotes a cable that covers the conductive wires connected to each of the coils 2 and 3 and connects it to one side of the storage container 4 with a hermetically shielded shield.
なお以上の実施例は、一枚の鋼板端の検出について述べ
たが、検出器を倣い台車に積載し、鋼板の両端に各々１
ケ以上取付ることにより、高温材、もしくは磁気分の多
く含んだ鋼板の幅を非接触で検出することもできる。In the above embodiment, the detection of the edge of one steel plate was described, but the detector was loaded on a tracing trolley, and one detector was installed at each end of the steel plate.
By attaching more than 1000 yen, it is also possible to detect the width of high-temperature materials or steel plates containing a large amount of magnetic content without contact.
更に、本発明は、渦電流効果の原理を使用している為鋼
板に限らず、導電性を有する材料において、その材料端
の変位検出することもできる。以上で述べた実施例では
一体物の変形フェライトに検出コイル２と基準コイル３
を対向巻回して、ステンレスケースにセット収納すると
いう単純構造であるため非常に小型、軽量に製作するこ
とができあらゆるシステムに組み込むことができる。Furthermore, since the present invention uses the principle of the eddy current effect, it is possible to detect displacement at the edge of a material not only a steel plate but also a conductive material. In the embodiment described above, the detection coil 2 and the reference coil 3 are integrated into the deformed ferrite body.
Because it has a simple structure of winding oppositely and storing it as a set in a stainless steel case, it can be made extremely compact and lightweight and can be incorporated into any system.
更に単純構造のため安価に製作することができる。以上
のように、この発明に係るエッジ検出器は鋼板のエッジ
を非接触でしかも雰囲気温度に影響されず精度よく検出
することが出来る。Furthermore, because of its simple structure, it can be manufactured at low cost. As described above, the edge detector according to the present invention can accurately detect the edge of a steel plate in a non-contact manner and without being affected by ambient temperature.
第１図はこの発明の一実施例を示す構造図、第２図は鋼
板に第１図に示す検出器を設置した時の状態図、第３図
は第２図に示す検出器の出力特性を示す特性図である。
図中、１は変形フェライト、１′はフェライト板、２は
検出コイル、３は基準コイル、４はステンレス外箱であ
る。５はケーブル、６は充填材である。
なお、図中同一符号は同一又は相当部分を示す。第１図
第２図
第３図Fig. 1 is a structural diagram showing an embodiment of the present invention, Fig. 2 is a state diagram when the detector shown in Fig. 1 is installed on a steel plate, and Fig. 3 is the output characteristics of the detector shown in Fig. 2. FIG. In the figure, 1 is a deformed ferrite, 1' is a ferrite plate, 2 is a detection coil, 3 is a reference coil, and 4 is a stainless steel outer box. 5 is a cable, and 6 is a filler. Note that the same reference numerals in the figures indicate the same or equivalent parts. Figure 1 Figure 2 Figure 3
Claims (1)
ジを検出するものにおいて、収納容器内に上・下それぞ
れに３個の突条部を有する一体物の■型フエライトを収
納し、このフエライトの一方の中央突条部に検出コイル
を巻回して上記圧延板を介する磁路を形成すると共に、
上記フエライトの他方の突条部にフエライト板を係合さ
せ且つ他方の中央突条部に基準コイルを巻回して上記フ
エライト板を介する磁路を形成し、上記基準コイルの基
準インダクタンスに対する上記検出コイルのインダクタ
ンス変化を検出するようにしたエツジ検出器。1. In the device for detecting the edge of the above-mentioned rolled plate installed opposite to the hot rolled plate, an integral ■-shaped ferrite having three protrusions on each of the upper and lower sides is housed in the storage container, A detection coil is wound around one central protrusion of this ferrite to form a magnetic path through the rolled plate, and
A ferrite plate is engaged with the other protrusion of the ferrite, and a reference coil is wound around the other central protrusion to form a magnetic path through the ferrite plate, and the detection coil corresponds to the reference inductance of the reference coil. An edge detector designed to detect changes in inductance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP54055127A JPS6020708B2 (en) | 1979-05-04 | 1979-05-04 | edge detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP54055127A JPS6020708B2 (en) | 1979-05-04 | 1979-05-04 | edge detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS55147373A JPS55147373A (en) | 1980-11-17 |
| JPS6020708B2 true JPS6020708B2 (en) | 1985-05-23 |
Family
ID=12990088
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP54055127A Expired JPS6020708B2 (en) | 1979-05-04 | 1979-05-04 | edge detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6020708B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992014145A1 (en) * | 1991-02-04 | 1992-08-20 | Nkk Corporation | Magnetic inspecting method and device therefor |
-
1979
- 1979-05-04 JP JP54055127A patent/JPS6020708B2/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992014145A1 (en) * | 1991-02-04 | 1992-08-20 | Nkk Corporation | Magnetic inspecting method and device therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55147373A (en) | 1980-11-17 |
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