JPH07229955A - Increment magnetic permeability measuring apparatus for magnetic steel plate - Google Patents
Increment magnetic permeability measuring apparatus for magnetic steel plateInfo
- Publication number
- JPH07229955A JPH07229955A JP2389394A JP2389394A JPH07229955A JP H07229955 A JPH07229955 A JP H07229955A JP 2389394 A JP2389394 A JP 2389394A JP 2389394 A JP2389394 A JP 2389394A JP H07229955 A JPH07229955 A JP H07229955A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- steel plate
- magnetic steel
- steel sheet
- magnetic field
- 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.)
- Granted
Links
Landscapes
- Measuring Magnetic Variables (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は大型の磁性鋼板の増分
透磁率の計測装置に関し、例えば磁気シールドルームに
使用するＰＣパーマロイ板などの大型の磁性鋼板の増分
透磁率を原板のまま計測できる計測装置に関するもので
ある。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for measuring the incremental magnetic permeability of a large magnetic steel plate, which is capable of measuring the incremental magnetic permeability of a large magnetic steel plate such as a PC permalloy plate used in a magnetically shielded room as it is. It relates to the device.
【０００２】[0002]
【従来の技術】磁気シールドルームの変動磁場のシール
ド性能は、側壁に使用される磁性鋼板の増分透磁率によ
り決まる。したがって鋼板の製造工程に於ける増分透磁
率の計測、管理はきわめて重要である。これに対して、
鋼板の透磁率の計測、管理は従来ＪＩＳＣ２５３１に定
める方法により行われてきた。これは製品鋼板の同じ製
造過程をたどった小リング片により初透磁率を計測する
ものである。2. Description of the Related Art The shielding performance of a magnetically shielded room against fluctuating magnetic fields is determined by the incremental permeability of magnetic steel sheets used for the side walls. Therefore, it is extremely important to measure and control the incremental magnetic permeability in the steel plate manufacturing process. On the contrary,
The measurement and management of the magnetic permeability of a steel sheet have been conventionally performed by the method specified in JISC2531. This is to measure the initial permeability by a small ring piece that follows the same manufacturing process of the product steel sheet.
【０００３】しかしながら、ＪＩＳＣ２５３１の方法に
は次の問題点がある。 １）直流の磁気シールド性能を決定する初透磁率の計測
法であり、増分透磁率の定量評価ではない。 ２）小リング片は大型鋼板と熱処理時の雰囲気条件が異
なり、透磁率が一致しないことがある。 一方、小型鋼板を計測する方法としては従来よりａエプ
スタイン試験法、ｂ単板試験法がある。しかしながら、
本方法は小型鋼板サンプルの計測を前提としており、大
型鋼板の計測を行なうにあたっては次の問題点がある。 ａ）の方法は複数の鋼板サンプルを井形に組んで計測す
るために大きな場所が必要であり、鋼板の個別管理がで
きない。 ｂ）の方法はヨークを組み合わせて計測するために装置
が重くなり、また大型鋼板とヨークのギャップ管理が困
難となる。However, the method of JIS C2531 has the following problems. 1) This is a measurement method of the initial magnetic permeability that determines the DC magnetic shield performance, not a quantitative evaluation of the incremental magnetic permeability. 2) The small ring pieces may have different magnetic permeability from the large steel plate due to different atmospheric conditions during heat treatment. On the other hand, as a method for measuring a small steel plate, there are conventionally an apstein test method and a b single plate test method. However,
This method is premised on the measurement of a small steel plate sample, and has the following problems when measuring a large steel plate. The method of a) requires a large space to measure a plurality of steel plate samples by forming them in a well shape, and thus individual management of steel plates cannot be performed. In the method of b), since the measurement is performed by combining the yokes, the apparatus becomes heavy, and it becomes difficult to manage the gap between the large steel plate and the yokes.
【０００４】[0004]
【発明が解決しようとする課題】この発明はかかる問題
点を解決するためになされたもので、磁性鋼板を励磁用
コイルの内部に挿入して交流を通電し、該磁性鋼板の表
面から夫々異なった距離に配置された少なくとも２個の
磁界検出器により磁界の強さを計測し、磁束検出用コイ
ルにより鋼板を透過する磁束を検出し、磁性鋼板近傍の
磁界の強さは磁性鋼板表面からの距離の１次関数となる
ことを利用して、磁界検出器の出力信号と磁束検出用コ
イルの出力信号とに基づいて増分透磁率を求めることに
より、ヨークなどを伴わない単純な装置で、大型の磁性
鋼板の増分透磁率を原板のまま計測することができる磁
性鋼板の増分透磁率計測装置を得ることを目的とする。SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a magnetic steel sheet is inserted into an exciting coil to energize an alternating current, and the surface of the magnetic steel sheet is different from each other. The strength of the magnetic field is measured by at least two magnetic field detectors arranged at different distances, and the magnetic flux that passes through the steel plate is detected by the magnetic flux detection coil. By utilizing the fact that it is a linear function of the distance, the incremental magnetic permeability is obtained based on the output signal of the magnetic field detector and the output signal of the magnetic flux detection coil. It is an object of the present invention to obtain an incremental magnetic permeability measuring device for a magnetic steel sheet capable of measuring the incremental magnetic permeability of the magnetic steel sheet as it is.
【０００５】[0005]
【課題を解決するための手段】この発明に係る磁性鋼板
の増分透磁率計測装置は、磁性鋼板を内部に挿入して交
流を通電し、磁界を発生させる励磁用コイルと、磁性鋼
板と励磁用コイルの間において、該磁性鋼板の一方の面
から夫々異なった距離に配置された少なくとも２個の磁
界検出器と、磁性鋼板内を透過する磁束を検出するため
に磁性鋼板と交叉して配置された磁束検出用コイルと、
前記複数の磁界検出器の出力信号から磁性鋼板内の磁界
の強さを求め、その値と磁束検出用コイルの出力信号か
ら得られる磁性鋼板内を透過する磁束の磁束密度とから
該磁性鋼板の増分透磁率を求める演算装置とを備えたも
のである。SUMMARY OF THE INVENTION An incremental magnetic permeability measuring apparatus for a magnetic steel sheet according to the present invention includes an exciting coil for inserting a magnetic steel sheet inside to energize an alternating current to generate a magnetic field, a magnetic steel sheet and an exciting coil. Between the coils, at least two magnetic field detectors are arranged at different distances from one surface of the magnetic steel plate, and are arranged so as to intersect with the magnetic steel plate to detect the magnetic flux passing through the magnetic steel plate. Magnetic flux detection coil,
Obtain the strength of the magnetic field in the magnetic steel sheet from the output signals of the plurality of magnetic field detectors, from the value and the magnetic flux density of the magnetic flux passing through the magnetic steel sheet obtained from the output signal of the magnetic flux detection coil of the magnetic steel sheet And an arithmetic unit for obtaining the incremental magnetic permeability.
【０００６】また、磁界検出器は磁性鋼板の両側に夫々
少なくとも２個ずつ配置するものである。Further, at least two magnetic field detectors are arranged on each side of the magnetic steel plate.
【０００７】さらに、磁性鋼板を内部に挿入して交流を
通電し、磁界を発生させる励磁用コイルと、磁性鋼板と
励磁用コイルの間において、該磁性鋼板の表面から垂直
方向に移動可能に配置された磁界検出器と、磁性鋼板内
を透過する磁束を検出するために磁性鋼板と交叉して配
置された磁束検出用コイルと、磁界検出器を移動させて
磁性鋼板の表面からの距離が夫々異なった少なくとも２
個所で得られる該磁界検出器の出力信号から磁性鋼板内
の磁界の強さを求め、その値と磁束検出用コイルの出力
信号から得られる磁性鋼板内を透過する磁束の磁束密度
とから該磁性鋼板の増分透磁率を求めるものである。Further, a magnetic steel plate is inserted inside to energize an alternating current to generate a magnetic field, and between the magnetic steel plate and the exciting coil is arranged so as to be vertically movable from the surface of the magnetic steel plate. The magnetic field detector, the magnetic flux detecting coil arranged to intersect with the magnetic steel plate to detect the magnetic flux passing through the magnetic steel plate, and the distance from the surface of the magnetic steel plate by moving the magnetic field detector. At least two different
The strength of the magnetic field in the magnetic steel sheet is obtained from the output signal of the magnetic field detector obtained at the location, and the magnetic field is determined from the value and the magnetic flux density of the magnetic flux passing through the magnetic steel sheet obtained from the output signal of the magnetic flux detection coil. This is to obtain the incremental magnetic permeability of the steel sheet.
【０００８】また、励磁用コイルにより発生させる磁界
の強さは１０-2Ｏｅ以下とするものである。The strength of the magnetic field generated by the exciting coil is set to 10 -2 Oe or less.
【０００９】さらに、励磁用コイルの長さを磁性鋼板の
長さと同等又はこれをより大きくし、磁界検出器及び磁
束検出用コイルを、磁性鋼板の長手方向を３等分したそ
の中央部内に配置し、磁界検出器は磁性鋼板と励磁用コ
イルとの間の磁性鋼板側の３分の１の空間内に配置する
ものである。Further, the length of the exciting coil is made equal to or longer than the length of the magnetic steel plate, and the magnetic field detector and the magnetic flux detecting coil are arranged in the central portion of the magnetic steel plate divided into three equal parts in the longitudinal direction. However, the magnetic field detector is arranged in the space of one-third of the magnetic steel sheet side between the magnetic steel sheet and the exciting coil.
【００１０】[0010]
【作用】この発明においては、磁性鋼板を励磁用コイル
の内部に挿入して交流を通電し、磁界を発生させ、磁性
鋼板の一方の面から夫々異なった距離に配置された少な
くとも２個の磁界検出器の出力信号、あるいは磁界検出
器を移動させて磁性鋼板の表面からの距離が夫々異なっ
た少なくとも２個所で得られる磁界検出器の出力信号か
ら磁性鋼板内の磁界の強さを求め、その値と磁束検出用
コイルの出力信号から得られる磁性鋼板内を透過する磁
束の磁束密度とから増分透磁率を求めるから、大型の磁
性鋼板の増分透磁率を原板のまま計測することができ
る。According to the present invention, the magnetic steel sheet is inserted into the exciting coil, an alternating current is applied to generate a magnetic field, and at least two magnetic fields are arranged at different distances from one surface of the magnetic steel sheet. The strength of the magnetic field in the magnetic steel sheet is calculated from the output signal of the detector or the output signal of the magnetic field detector obtained by moving the magnetic field detector at at least two locations at different distances from the surface of the magnetic steel sheet. Since the incremental magnetic permeability is obtained from the value and the magnetic flux density of the magnetic flux passing through the magnetic steel sheet obtained from the output signal of the magnetic flux detecting coil, the incremental magnetic permeability of a large magnetic steel sheet can be measured as the original plate.
【００１１】また、磁界検出器は磁性鋼板の両側に夫々
少なくとも２個ずつ配置することにより、磁性鋼板の厚
さ方向に磁界分布の偏差が生じた場合、その偏差を検出
できる。Further, by arranging at least two magnetic field detectors on each side of the magnetic steel plate, when a magnetic field distribution deviation occurs in the thickness direction of the magnetic steel plate, the deviation can be detected.
【００１２】さらに、励磁用コイルにより発生させる磁
界の強さは１０-2Ｏｅ以下とすることにより、磁気シー
ルドルームが設置される場所、例えば大都市の病院等に
おける微弱な磁気雑音に対する特性がわかる。Further, by setting the strength of the magnetic field generated by the exciting coil to 10 -2 Oe or less, the characteristics against weak magnetic noise in a place where a magnetic shield room is installed, for example, in a hospital in a big city can be known. .
【００１３】また、磁界検出器及び磁束検出用コイル
を、磁性鋼板の長手方向を３等分したその中央部分内に
配置し、磁界検出器は磁性鋼板と励磁用コイルとの間の
磁性鋼板側の３分の１の空間内に配置することにより、
磁界検出器の設置される位置が磁性鋼板の長手方向中央
からずれていても増分透磁率の計測ができる。Further, the magnetic field detector and the magnetic flux detecting coil are arranged in the central portion of the magnetic steel plate which is divided into three equal parts in the longitudinal direction, and the magnetic field detector is located on the magnetic steel plate side between the magnetic steel plate and the exciting coil. By arranging it in the space of 1/3 of
Even if the position where the magnetic field detector is installed is displaced from the longitudinal center of the magnetic steel sheet, the incremental permeability can be measured.
【００１４】[0014]
実施例１．先ず、この発明の原理について説明する。図
１はこの発明の実施例１における励磁部及びセンサ部を
示す正面図、図２は図１のＡ−Ａ線断面図である。図に
おいて、１は増分透磁率が計測される大型の磁性鋼板
（以下、単に鋼板と記す）で、例えばＰＣパーマロイの
原板である。２は被試験材である鋼板を交流で励磁する
励磁用コイルで、鋼板１を内部に挿入して励磁するのに
充分な横断面（長手方向に直交する断面）と長さを有
し、かつ横断面が方形のコイルである。方形のコイルに
したのは、鋼板１の幅方向に均一な磁界を発生させるた
めである。従って、鋼板１は、方形のコイルの内部中央
に、方形のコイルの幅Ｗ方向の導線が鋼板１に平行とな
るように、挿入して計測する。３は鋼板内を透過する磁
束を検出するために鋼板１と交叉して配置された磁束検
出用コイル、４ａ，４ｂは磁界検出器で、ガウスメータ
等の磁力計である。２個の磁力計は鋼板１の表面、即ち
一方の面から異なる位置の磁界の強さを計測するもので
ある。そして、励磁用コイル２により励磁部が構成さ
れ、磁束検出用コイル３及び磁力計４ａ，４ｂによりセ
ンサ部が構成されている。Example 1. First, the principle of the present invention will be described. 1 is a front view showing an exciting unit and a sensor unit in Embodiment 1 of the present invention, and FIG. 2 is a sectional view taken along line AA of FIG. In the figure, 1 is a large magnetic steel plate (hereinafter, simply referred to as a steel plate) whose incremental magnetic permeability is measured, and is, for example, a PC permalloy original plate. Reference numeral 2 denotes an exciting coil that excites a steel sheet as a material to be tested with an alternating current, and has a transverse section (cross section orthogonal to the longitudinal direction) and a length that are sufficient for exciting the steel sheet 1 by inserting it inside, and The coil has a rectangular cross section. The rectangular coil is used to generate a uniform magnetic field in the width direction of the steel plate 1. Therefore, the steel plate 1 is inserted and measured in the center of the inside of the rectangular coil so that the conductor in the width W direction of the rectangular coil is parallel to the steel plate 1. Reference numeral 3 denotes a magnetic flux detecting coil arranged to intersect with the steel plate 1 to detect the magnetic flux passing through the steel plate, and 4a and 4b are magnetic field detectors, which are magnetometers such as Gauss meters. The two magnetometers measure the strength of the magnetic field at different positions from the surface of the steel plate 1, that is, one surface. The exciting coil 2 constitutes an exciting section, and the magnetic flux detecting coil 3 and the magnetometers 4a and 4b constitute a sensor section.
【００１５】磁力計４ａ，４ｂ及び磁束検出コイル３
は、励磁用コイル２に挿入された鋼板１の長手方向中央
に配置され、かつ、磁力計４ａと４ｂは鋼板１の表面、
即ち一方の面から夫々異なった距離に配置されている。
また、励磁用コイル１、磁束検出用コイル３及び磁力計
４ａ，４ｂは夫々上述の位置を保って周知の手段により
固定されている。励磁用コイル２は、巻枠に巻かれてお
り、その外形寸法は、長さＬ＝１８００ｍｍ、幅Ｗ＝８
５０ｍｍ、高さＨ＝４００ｍｍである。鋼板１は、幅Ｗ
＝６００ｍｍ、厚さＴ＝１．２ｍｍ、長さＬは励磁コイ
ル２の長さと同等又はこれより小である。Magnetometers 4a and 4b and magnetic flux detecting coil 3
Is arranged at the center in the longitudinal direction of the steel plate 1 inserted in the exciting coil 2, and the magnetometers 4a and 4b are the surface of the steel plate 1,
That is, they are arranged at different distances from one surface.
The exciting coil 1, the magnetic flux detecting coil 3, and the magnetometers 4a and 4b are fixed by known means while maintaining the above positions. The exciting coil 2 is wound on a winding frame, and the outer dimensions thereof are length L = 1800 mm and width W = 8.
The height is 50 mm and the height H is 400 mm. Steel plate 1 has a width W
= 600 mm, thickness T = 1.2 mm, and length L is equal to or smaller than the length of the exciting coil 2.
【００１６】上記のように構成して、鋼板１を励磁コイ
ル２の内部に挿入して交流を通電し、微弱な磁界を発生
させ、磁力計４ａ，４ｂにより磁界を測定し、磁束検出
用コイル３の出力信号に基づいて磁束密度を求め増分透
磁率を計測するのであるが、最大の問題点は、被試験材
である鋼板を含む磁路に大ギャップが存在するため鋼板
端部に反磁界が発生し、表面も含めた鋼板内部と鋼板の
表面（以下、鋼板面と記す）近傍とで磁界の強さが異な
ることである。そこで、発明者は磁場解析及び実験によ
り下記の事実を確認した。即ち、「励磁用コイル中心部
において鋼板面近傍の磁界の強さは、鋼板面からの距離
の１次関数となり鋼板面及び鋼板内部にて最小とな
る。」With the above construction, the steel plate 1 is inserted into the exciting coil 2 to pass an alternating current to generate a weak magnetic field, and the magnetic field is measured by the magnetometers 4a and 4b to detect the magnetic flux. The magnetic flux density is calculated based on the output signal of No. 3, and the incremental magnetic permeability is measured. Occurs, and the strength of the magnetic field differs between the inside of the steel sheet including the surface and the vicinity of the surface of the steel sheet (hereinafter referred to as the steel sheet surface). Therefore, the inventor confirmed the following facts by magnetic field analysis and experiments. That is, "the strength of the magnetic field in the vicinity of the steel plate surface at the center of the exciting coil is a linear function of the distance from the steel plate surface and is minimum on the steel plate surface and inside the steel plate."
【００１７】以下、本事実を大型計算機を使用した磁場
解析計算にて明らかにする。解析は図１及び図２に示す
装置の１／１０のモデルを前提とし、鋼板の幅方向の磁
場分布がほぼ一様であるとして積分要素法解析計算のう
ちベクトルポテンシャル法（Ａ−φ法）２次元線形静磁
場解析を用いた。対称性を考えて、図３に示す模型の１
／４の部分（第１象限）について解析した。コイル２ａ
（第１象限）は紙面上から下に向う方向に電流が流れて
いる。対象軸Ｘは磁位の固定境界、対象軸Ｚは磁位の自
由境界、その他の境界（−で示される部分）は積分境界
とする。μΔ（比透磁率）を１０，０００で計算した結
果を図４に示す。図４からわかるように、磁界の強さ
（Ｘ方向成分）は、鋼板（ＰＣパーマロイ）１ａの表面
から直線で変化し、鋼板内では一定の値である。なお、
鋼板１の長さＬ方向をＸ軸、幅Ｗ方向をＹ軸、鋼板に垂
直方向をＺ軸とする。実験結果については後述する。Hereinafter, this fact will be clarified by a magnetic field analysis calculation using a large-scale computer. The analysis is based on the model of 1/10 of the apparatus shown in FIGS. 1 and 2, and the vector potential method (A-φ method) of the integral element method analysis calculation assuming that the magnetic field distribution in the width direction of the steel sheet is almost uniform. Two-dimensional linear static magnetic field analysis was used. Considering the symmetry, 1 of the model shown in FIG.
The / 4 portion (first quadrant) was analyzed. Coil 2a
In the (first quadrant), an electric current flows from the top to the bottom of the drawing. The target axis X is a fixed boundary of the magnetic potential, the target axis Z is a free boundary of the magnetic potential, and the other boundaries (portions indicated by-) are integration boundaries. FIG. 4 shows the result of calculation of μΔ (relative magnetic permeability) at 10,000. As can be seen from FIG. 4, the strength of the magnetic field (X-direction component) changes linearly from the surface of the steel plate (PC permalloy) 1a and has a constant value within the steel plate. In addition,
The length L direction of the steel sheet 1 is the X axis, the width W direction is the Y axis, and the direction perpendicular to the steel sheet is the Z axis. The experimental results will be described later.
【００１８】そして、上記の解析結果に基づいて、鋼板
面からの距離を変えて鋼板面近傍の２点の磁界の強さ
（交流分）を計測し、その値と２点の距離から鋼板面上
の磁界の強さを計算する方法を導いた。図５は鋼板面上
及び内部の磁界の強さを求める方法の原理を説明する説
明図で、図５（ａ）は鋼板１に対し磁力計４ａ，４ｂを
配置する位置を示す図であり、図５（ｂ）は上記解析結
果に基づいた鋼板面近傍の磁界の強さ（Ｘ方向成分）は
鋼板面からの距離の１次関数となることを示すグラフで
ある。なお、（ａ）図の磁力計４ａ，４ｂの位置Ｚ1 ，
Ｚ2 と（ｂ）図の縦軸のＺ1，Ｚ2 とは対応している。
ここで、 Ｚ1 ：鋼板面と磁力計１との距離 Ｚ2 ：鋼板面と磁力計２との距離 Ｈ1 ：磁力計１の計測データ（磁界の強さ） Ｈ2 ：磁力計２の計測データ（磁界の強さ） とすると、鋼板からｚのところにある点の磁界の強さＨ
（ｚ）は （Ｈ（ｚ）−Ｈ1 ）／（ｚ−ｚ1 ）＝（Ｈ2 −Ｈ1 ）／（ｚ2 −ｚ1 ） …（１） であらわせる。鋼板面上（ｚ＝０）の磁界の強さは、 Ｈ（０）＝（−ｚ1 ・Ｈ2 ＋ｚ2 ・Ｈ1 ）／（ｚ2 −ｚ1 ） …（２） である。一方、 τ：鋼板の厚さ ｗ：鋼板の幅 Ｖ：磁束検出用コイルの出力 ｎ：磁束検出用コイルの巻き数 とすれば、鋼板の内部を透過する磁束の磁束密度はThen, based on the above analysis results, the magnetic field strength (AC component) at two points near the steel plate surface is measured while changing the distance from the steel plate surface, and the value and the distance between the two points are used to measure the steel plate surface. The method of calculating the above magnetic field strength is derived. FIG. 5 is an explanatory view for explaining the principle of the method for obtaining the strength of the magnetic field on the steel plate surface and inside, and FIG. 5 (a) is a view showing the positions where the magnetometers 4a, 4b are arranged on the steel plate 1, FIG. 5B is a graph showing that the magnetic field strength (X-direction component) near the steel plate surface based on the above analysis results is a linear function of the distance from the steel plate surface. The position Z 1 of the magnetometers 4a and 4b in FIG.
Z 2 corresponds to Z 1 and Z 2 on the vertical axis in FIG.
Here, Z 1 : distance between the steel plate surface and the magnetometer 1 Z 2 : distance between the steel plate surface and the magnetometer 2 H 1 : measurement data of the magnetometer 1 (magnetic field strength) H 2 : measurement of the magnetometer 2 Given the data (magnetic field strength), the magnetic field strength H at the point z from the steel plate
(Z) can be expressed by (H (z) -H 1) / (z-z 1) = (H 2 -H 1) / (z 2 -z 1) ... (1). The strength of the magnetic field on the steel plate surface (z = 0) is H (0) = (− z 1 · H 2 + z 2 · H 1 ) / (z 2 −z 1 ) ... (2). On the other hand, τ is the thickness of the steel plate, w is the width of the steel plate, V is the output of the coil for detecting magnetic flux, and n is the number of turns of the coil for detecting magnetic flux.
【００１９】[0019]
【数１】 これより増分透磁率μΔは、 μΔ＝Ｂ／Ｈ（０） …（４） で求まる。以上のことから、この発明は少なくとも２個
の磁力計で鋼板近傍の２点の磁界の強さを計測し、その
情報を演算装置で処理して鋼板面、つまり鋼板内の磁界
の強さを求め、同時に計測した鋼板の磁束密度との比を
とることにより増分透磁率を計測するものである。[Equation 1] From this, the incremental magnetic permeability μΔ is obtained by μΔ = B / H (0) (4). From the above, the present invention measures the strength of the magnetic field at two points near the steel plate with at least two magnetometers and processes the information by a computing device to determine the strength of the magnetic field in the steel plate, that is, in the steel plate. The incremental magnetic permeability is measured by calculating the ratio with the magnetic flux density of the steel sheet obtained and measured at the same time.
【００２０】図６はこの発明の実施例１による増分透磁
率計測装置の構成図である。図６において、２は励磁コ
イル、３は磁束検出用コイル、４ａ，４ｂは磁力計であ
り、図１及び図２に示すものを構成図として示したもの
である。なお、鋼板１は図示を省略してある。５は励磁
用交流を発生する発振器、６は発振器５の出力を増幅し
て励磁用コイル２へ出力する増幅器、７は比例・積分演
算プロセッサ、８は加減乗除演算プロセッサである。FIG. 6 is a block diagram of an incremental magnetic permeability measuring apparatus according to Embodiment 1 of the present invention. In FIG. 6, 2 is an exciting coil, 3 is a magnetic flux detecting coil, 4a and 4b are magnetometers, and the one shown in FIGS. 1 and 2 is shown as a configuration diagram. The steel plate 1 is not shown. Reference numeral 5 is an oscillator that generates an alternating current for excitation, 6 is an amplifier that amplifies the output of the oscillator 5 and outputs it to the excitation coil 2, 7 is a proportional / integral arithmetic processor, and 8 is an add / subtract / multiply / divide arithmetic processor.
【００２１】次に、動作を説明する。励磁用コイル２
は、増幅器６の出力により励磁を行う。周波数は被試験
材である鋼板１に渦電流が発生しない範囲であり、１ｍ
ｍ厚さのＰＣパーマロイの場合は０．１〜１０Ｈｚ程度
である。周波数の下限は０．１Ｈｚとする。これは、磁
気シールドルームの主な用途としては医療用で人体から
発生する磁場の強さの測定を行う場の提供であり、この
ようなシールドルームに使用する材料を評価するために
は、人体から発生する磁場の周波数帯に対応した０．１
Ｈｚ程度における増分透磁率がわかればよいからであ
る。なお、現在の測定器の性能等からすると、０．０１
Ｈｚ位迄の範囲で測定が可能である。磁界の強さは、１
０-2Ｏｅ以下で計測を行う。これは、都市に於ける磁気
変動のレベルが１０-3Ｏｅのオーダであることによる。
即ち、上述の人体から発生する磁場の強さの測定を行う
ための磁気シールドルームが、都市の病院に設置された
場合のことを考えると１０-3Ｏｅクラスの磁気雑音をシ
ールドする必要がある。従って、材料としてのＰＣパー
マロイも１０-3Ｏｅクラスの微弱な磁界での特性を評価
する必要がある。以上のことから磁界の強さは１０-2Ｏ
ｅ以下とする。一方、鋼板１を完全に励磁するために励
磁コイル２の長さは鋼板の長さより小さくならないよう
にする。Next, the operation will be described. Excitation coil 2
Excites with the output of the amplifier 6. The frequency is the range where eddy current is not generated in the steel plate 1 as the material under test, and is 1 m.
In the case of PC permalloy having a thickness of m, the frequency is about 0.1 to 10 Hz. The lower limit of the frequency is 0.1 Hz. This is to provide a place to measure the strength of the magnetic field generated by the human body for medical purposes as the main application of the magnetically shielded room.To evaluate the materials used in such a shielded room, 0.1 corresponding to the frequency band of the magnetic field generated from
This is because it is sufficient to know the incremental magnetic permeability at about Hz. In addition, from the current performance of measuring instruments, etc., 0.01
It is possible to measure in the range up to Hz. The strength of the magnetic field is 1
Measurement is performed at 0 -2 Oe or less. This is because the level of magnetic fluctuations in cities is on the order of 10 -3 Oe.
That is, considering the case where the above-mentioned magnetic shield room for measuring the strength of the magnetic field generated from the human body is installed in a city hospital, it is necessary to shield the magnetic noise of 10 −3 Oe class. . Therefore, it is necessary to evaluate the characteristics of PC permalloy as a material in a weak magnetic field of 10 −3 Oe class. From the above, the magnetic field strength is 10 -2 O
e or less. On the other hand, in order to completely excite the steel sheet 1, the length of the exciting coil 2 should not be smaller than the length of the steel sheet.
【００２２】周波数、磁界の強さは増幅器６の前段にあ
る発振器５にて調整する。磁力計４ａ，４ｂ及び磁束検
出用コイル３の出力信号は比例・積分演算プロセッサ７
で処理される。磁力計４ａ，４ｂの２信号は比例演算に
より磁界の強さＨ1 ，Ｈ2 の値に変換され加減乗除演算
プロセッサ８に送られる。磁束検出用コイル３の出力信
号は積分演算により磁束密度Ｂの値に変換され加減乗除
算演算プロセッサ８に送られる。加減乗除演算プロセッ
サ８には、予め磁力計４ａ，４ｂの位置Ｚ1 ，Ｚ2 の情
報がインプットされており、式（２）に基づいて鋼板面
上の磁界の強さが計算され、式（４）に基づいて増分透
磁率μΔが計算され出力される。The frequency and the strength of the magnetic field are adjusted by the oscillator 5 in front of the amplifier 6. The output signals of the magnetometers 4a and 4b and the magnetic flux detecting coil 3 are proportional / integral arithmetic processors 7
Is processed in. The two signals of the magnetometers 4a and 4b are converted into the values of the magnetic field strengths H 1 and H 2 by the proportional calculation and sent to the addition / subtraction / multiplication / division calculation processor 8. The output signal of the magnetic flux detecting coil 3 is converted into a value of the magnetic flux density B by integral calculation and sent to the addition / subtraction / multiplication / division calculation processor 8. Information on the positions Z 1 and Z 2 of the magnetometers 4a and 4b is input to the addition / subtraction / multiplication / division calculation processor 8 in advance, and the strength of the magnetic field on the steel plate surface is calculated based on the equation (2) to obtain the equation ( Based on 4), the incremental magnetic permeability μΔ is calculated and output.
【００２３】実施例２．上記実施例１は、磁力計４ａ，
４ｂ及び磁束検出用コイル３を鋼板１の長手方向中央に
配置したものであるが、中央からずれた位置に配置して
も計測は可能である。実施例２は磁力計及び磁束検出用
コイルを鋼板の長手方向を３等分したその中央部内に配
置し、磁力計を鋼板と励磁用コイルとの間の鋼板側の３
分の１の空間内に配置するものである。以下、図２と同
じ位置で断面した図７を用いて説明する。図７は励磁コ
イル内の高さ方向、つまり鋼板面に垂直方向の磁界分布
を知るための実験を説明する説明図で、（ａ）は１個の
磁力計４の位置を変えて磁界の強さを計測する構成を示
す図、（ｂ）は鋼板１の一部を励磁用コイル２から出し
て計測する状態を示し、（ｃ）は鋼板１を励磁用コイル
２の中央におき、鋼板１の長手方向端部近傍の磁界を計
測する状態を示す図である。Example 2. In the first embodiment, the magnetometer 4a,
4b and the magnetic flux detecting coil 3 are arranged at the center of the steel plate 1 in the longitudinal direction, but measurement is possible even if they are arranged at positions deviated from the center. In the second embodiment, the magnetometer and the magnetic flux detecting coil are arranged in the central portion of the steel plate which is divided into three equal parts in the longitudinal direction, and the magnetometer is provided on the steel plate side between the steel plate and the exciting coil.
It is to be placed in one-half the space. Hereinafter, a description will be given with reference to FIG. 7 which is a cross section at the same position as in FIG. FIG. 7 is an explanatory diagram for explaining an experiment for knowing the magnetic field distribution in the height direction inside the exciting coil, that is, in the direction perpendicular to the steel plate surface. FIG. 7A shows the strength of the magnetic field by changing the position of one magnetometer 4. The figure which shows the structure which measures height, (b) shows the state which takes out a part of steel plate 1 from the coil 2 for excitation, and (c) puts the steel plate 1 in the center of the coil 2 for excitation, and shows the steel plate 1. FIG. 5 is a diagram showing a state in which a magnetic field near the end in the longitudinal direction of is measured.
【００２４】実験１は、（ｂ）図に示すように鋼板１を
励磁用コイル２から２５０ｍｍだけ出し、励磁用コイル
の端から２００ｍｍの所で、１個の磁力計４をＺ方向に
位置を変えて計測した。その結果を図８に示す。実験２
は、（ｃ）図に示すように、鋼板１の端部のＺで示す位
置において、１個の磁力計をＺ方向に位置を変えて計測
した。その計測結果を図９に示す。実験１及び２何れの
場合も、鋼板１からの距離が９０ｍｍまでは磁界分布に
直線性があるが、９０〜２００ｍｍの所では非線形にな
る。この結果に基づいて、鋼板１からの距離が９０ｍｍ
までの範囲に磁力計を置けば、磁力計の鋼板１の長手方
向に対する位置は中央からずれても直線性が得られるこ
とがわかる。In Experiment 1, as shown in FIG. 2 (b), the steel plate 1 was moved out from the exciting coil 2 by 250 mm, and one magnetometer 4 was positioned in the Z direction at a position 200 mm from the end of the exciting coil. I changed and measured. The result is shown in FIG. Experiment 2
Was measured by changing the position of one magnetometer in the Z direction at the position indicated by Z at the end of the steel plate 1 as shown in FIG. The measurement result is shown in FIG. In both Experiments 1 and 2, the magnetic field distribution has linearity up to a distance of 90 mm from the steel plate 1, but becomes non-linear at a location of 90 to 200 mm. Based on this result, the distance from the steel plate 1 is 90 mm
It is understood that if the magnetometer is placed in the range up to, linearity can be obtained even if the position of the magnetometer with respect to the longitudinal direction of the steel plate 1 deviates from the center.
【００２５】そこで、実施例２は、安全性を考慮して、
鋼板１と励磁用コイル２との間の鋼板側の３分の１の空
間内の位置に磁力計４ａ，４ｂを配置し、長手方向の位
置は、鋼板の長手方向を３等分したその中央部内に配置
するものである。この実施例２によれば、磁力計を配置
する上で、鋼板の長手方向については、必ずしも中央に
配置しなくてよいから、装置を製作する上で有利であ
る。Therefore, in the second embodiment, in consideration of safety,
Magnetometers 4a and 4b are arranged at positions within a third space between the steel plate 1 and the excitation coil 2 on the steel plate side, and the longitudinal position is the center of the longitudinal direction of the steel plate divided into three equal parts. It is to be placed in the department. According to the second embodiment, in disposing the magnetometer, the longitudinal direction of the steel plate does not necessarily have to be arranged in the center, which is advantageous in manufacturing the device.
【００２６】実施例３．上記実施例２の実験結果によれ
ば、磁界検出器は１個であってもよい。この場合は、磁
界検出器を鋼板１の表面、即ち一方の面から垂直方向に
移動させ、鋼板１からＺ1 の距離において得られる出力
信号と、鋼板１からＺ2 の距離において得られる出力信
号とに基づいて、比例・積分演算プロセッサ７により比
例演算して磁界の強さＨ1 及びＨ2 を求めれば、実施例
１と同様に増分透磁率を求めることができる。Example 3. According to the experimental result of the above-mentioned Example 2, the number of magnetic field detectors may be one. In this case, the surface of the steel sheet 1 and the magnetic field detector, i.e. is moved in a vertical direction from the one surface, and an output signal obtained at a distance from the steel plate 1 of Z 1, the output signal obtained at a distance from the steel plate 1 Z 2 Based on the above, if the proportional / integral calculation processor 7 calculates proportionally the magnetic field strengths H 1 and H 2 , the incremental magnetic permeability can be calculated as in the first embodiment.
【００２７】実施例４．実施例１及び２では、磁力計は
鋼板の片側に２個配置しているが、磁力計を鋼板の両側
に２個ずつ配置すれば、鋼板の両面における磁界の強さ
Ｈu （０），Ｈd （０）を計測できる。実施例３による
と鋼板の厚さ方向に磁界分布の偏差が生じた場合に、そ
の検出と補正（平均処理）が可能である。Example 4. In Examples 1 and 2, two magnetometers are arranged on one side of the steel plate. However, if two magnetometers are arranged on both sides of the steel plate, the magnetic field strengths Hu (0) on both sides of the steel plate, H d (0) can be measured. According to the third embodiment, when there is a deviation in the magnetic field distribution in the thickness direction of the steel sheet, it can be detected and corrected (average processing).
【００２８】実施例５．実施例１〜３では、磁界検出器
として磁力計を用いているが、磁力計のかわりに、ピッ
クアップコイル（空心コイル）を用い、比例・積分演算
プロセッサ７で積分処理を行ってＨ1 ，Ｈ2 を計算して
もよい。Example 5. In Examples 1 to 3, a magnetometer is used as the magnetic field detector. However, instead of the magnetometer, a pickup coil (air core coil) is used, and the proportional / integral calculation processor 7 performs integration processing to obtain H 1 , H 2. You may calculate 2 .
【００２９】[0029]
【発明の効果】この発明は以上説明したとおり、磁性鋼
板を励磁用コイルの内部に挿入して交流を通電し、磁界
を発生させ、磁性鋼板の一方の面から夫々異なった距離
に配置された少なくとも２個の磁界検出器の出力信号、
あるいは磁界検出器を移動させて磁性鋼板の表面からの
距離が夫々異なった少なくとも２個所で得られる磁界検
出器の出力信号から磁性鋼板内の磁界の強さを求め、そ
の値と磁束検出用コイルの出力信号から得られる磁性鋼
板内を透過する磁束の磁束密度とから増分透磁率を求め
るから、大型の磁性鋼板の増分透磁率を原板のまま計測
することができる。従って、 １）特に、磁気シールドルームなどに使用する大型磁性
板の増分透磁率計測が可能となり、従来の試験サンプル
片による計測に置ける代替計測のずれ、即ちサンプルと
実際の製品との間の特性の差が無くなる。 ２）単板試験法、エプスタイン試験法のような装置の大
型化、重量化、ギャップ管理の困難性の問題が解消す
る。As described above, according to the present invention, a magnetic steel plate is inserted into an exciting coil, an alternating current is applied to generate a magnetic field, and the magnetic steel plates are arranged at different distances from one surface of the magnetic steel plate. Output signals of at least two magnetic field detectors,
Alternatively, by moving the magnetic field detector, the strength of the magnetic field in the magnetic steel plate is obtained from the output signal of the magnetic field detector obtained at at least two locations at different distances from the surface of the magnetic steel plate, and the value and the coil for magnetic flux detection are obtained. Since the incremental magnetic permeability is obtained from the magnetic flux density of the magnetic flux that passes through the magnetic steel plate obtained from the output signal of, the incremental magnetic permeability of the large magnetic steel plate can be measured as the original plate. Therefore, 1) In particular, it becomes possible to measure the incremental permeability of a large magnetic plate used in a magnetically shielded room, etc., and the deviation of the alternative measurement in the measurement by the conventional test sample piece, that is, the characteristic between the sample and the actual product. The difference between 2) The problems of large size, heavy weight, and difficulty of gap management such as the single plate test method and the Epstein test method are solved.
【００３０】また、磁界検出器は磁性鋼板の両側に夫々
少なくとも２個ずつ配置することにより、磁性鋼板の厚
さ方向に磁界分布の偏差が生じた場合、その偏差を検出
できる。従って、厚さ方向の磁界分布の偏差の有無の評
価ができる。Further, by disposing at least two magnetic field detectors on each side of the magnetic steel sheet, when the magnetic field distribution has a deviation in the thickness direction of the magnetic steel sheet, the deviation can be detected. Therefore, it is possible to evaluate whether or not there is a deviation in the magnetic field distribution in the thickness direction.
【００３１】さらに、励磁用コイルにより発生させる磁
界の強さは１０-2Ｏｅ以下とすることにより、磁気シー
ルドルームが設置される場所、例えば都市の病院等にお
ける微弱な磁気雑音に対する特性がわかる。従って、微
弱な磁気雑音をシールドする磁気シールドルームの材料
として適しているか否かの評価ができる。Further, by setting the strength of the magnetic field generated by the exciting coil to 10 -2 Oe or less, the characteristics against a weak magnetic noise in a place where the magnetic shield room is installed, for example, in a hospital in a city can be known. Therefore, it is possible to evaluate whether or not it is suitable as a material for a magnetically shielded room that shields weak magnetic noise.
【００３２】また、磁界検出器及び磁束検出用コイル
を、磁性鋼板の長手方向を３等分したその中央部内に配
置し、磁界検出器は磁性鋼板と励磁用コイルとの間の磁
性鋼板側の３分の１の空間内に配置することにより、磁
界検出器の設置される位置が磁性鋼板の長手方向中央か
らずれていても増分透磁率の計測ができる。従って、磁
界検出器を配置する上で寸法的な余裕があるから、装置
を製作する上で有利である。Further, the magnetic field detector and the magnetic flux detecting coil are arranged in the central portion of the magnetic steel plate, which is divided into three equal parts in the longitudinal direction, and the magnetic field detector is located on the magnetic steel plate side between the magnetic steel plate and the exciting coil. By arranging in the space of 1/3, the incremental magnetic permeability can be measured even if the position where the magnetic field detector is installed deviates from the longitudinal center of the magnetic steel sheet. Therefore, there is a dimensional margin in arranging the magnetic field detector, which is advantageous in manufacturing the device.
【図１】この発明の実施例１における励磁部及びセンサ
部を示す正面図である。FIG. 1 is a front view showing an excitation unit and a sensor unit according to a first embodiment of the present invention.
【図２】図１のＡ−Ａ線断面図である。FIG. 2 is a sectional view taken along the line AA of FIG.
【図３】解析のための模型を示す説明図である。FIG. 3 is an explanatory diagram showing a model for analysis.
【図４】解析結果の一例を示す線図である。FIG. 4 is a diagram showing an example of an analysis result.
【図５】鋼板面上及び内部の磁界の強さを求める方法の
原理を説明する説明図である。FIG. 5 is an explanatory diagram illustrating the principle of a method for obtaining the strengths of magnetic fields on and inside a steel plate.
【図６】この発明の実施例１による増分透磁率計測装置
の構成図である。FIG. 6 is a configuration diagram of an incremental magnetic permeability measuring apparatus according to the first embodiment of the present invention.
【図７】鋼板面に垂直方向の磁界分布を知るための実験
を説明する説明図である。FIG. 7 is an explanatory diagram illustrating an experiment for knowing a magnetic field distribution in a direction perpendicular to a steel plate surface.
【図８】実験１の結果を示す線図である。FIG. 8 is a diagram showing the results of Experiment 1.
【図９】実験２の結果を示す線図である。9 is a diagram showing the results of Experiment 2. FIG.
１ 磁性鋼板 ２ 励磁用コイル ３ 磁束検出用コイル ４ａ，４ｂ 磁界検出器 ５ 発振器 ６ 増幅器 ７ 比例・積分演算プロセッサ ８ 加減乗除演算プロセッサ 1 Magnetic Steel Plate 2 Excitation Coil 3 Magnetic Flux Detection Coil 4a, 4b Magnetic Field Detector 5 Oscillator 6 Amplifier 7 Proportional / Integral Calculation Processor 8 Addition / Decrement / Division Calculation Processor
Claims (5)
し、磁界を発生させる励磁用コイルと、 前記磁性鋼板と励磁用コイルの間において、該磁性鋼板
の一方の面から夫々異なった距離に配置された少なくと
も２個の磁界検出器と、 前記磁性鋼板内を透過する磁束を検出するために前記磁
性鋼板と交叉して配置された磁束検出用コイルと、 前記複数の磁界検出器の出力信号から前記磁性鋼板内の
磁界の強さを求め、その値と前記磁束検出用コイルの出
力信号から得られる前記磁性鋼板内を透過する磁束の磁
束密度とから該磁性鋼板の増分透磁率を求める演算装置
とを備えた磁性鋼板の増分透磁率計測装置。1. An exciting coil that inserts a magnetic steel sheet inside to pass an alternating current to generate a magnetic field, and between the magnetic steel sheet and the exciting coil, different distances from one surface of the magnetic steel sheet. At least two magnetic field detectors arranged on the magnetic steel plate, a magnetic flux detecting coil arranged so as to intersect with the magnetic steel plate for detecting a magnetic flux passing through the magnetic steel plate, and outputs of the plurality of magnetic field detectors. The strength of the magnetic field in the magnetic steel sheet is obtained from the signal, and the incremental magnetic permeability of the magnetic steel sheet is obtained from the value and the magnetic flux density of the magnetic flux passing through the magnetic steel sheet obtained from the output signal of the magnetic flux detection coil. An incremental magnetic permeability measuring device for magnetic steel sheets, which comprises a computing device.
夫々少なくとも２個ずつ配置することを特徴とする請求
項１記載の磁性鋼板の増分透磁率計測装置。2. The incremental magnetic permeability measuring apparatus for a magnetic steel sheet according to claim 1, wherein at least two magnetic field detectors are arranged on each side of the magnetic steel sheet.
し、磁界を発生させる励磁用コイルと、 前記磁性鋼板と励磁用コイルの間において、該磁性鋼板
の表面から垂直方向に移動可能に配置された磁界検出器
と、 前記磁性鋼板内を透過する磁束を検出するために前記磁
性鋼板と交叉して配置された磁束検出用コイルと、 前記磁界検出器を移動させて前記磁性鋼板の表面からの
距離が夫々異なった少なくとも２個所で得られる該磁界
検出器の出力信号から前記磁性鋼板内の磁界の強さを求
め、その値と前記磁束検出用コイルの出力信号から得ら
れる前記磁性鋼板内を透過する磁束の磁束密度とから該
磁性鋼板の増分透磁率を求める演算装置とを備えた磁性
鋼板の増分透磁率計測装置。3. A magnetic steel sheet is inserted inside to energize an alternating current to generate a magnetic field, and between the magnetic steel sheet and the exciting coil, the magnetic steel sheet is movable vertically from the surface of the magnetic steel sheet. A magnetic field detector arranged, a magnetic flux detecting coil arranged so as to intersect with the magnetic steel plate in order to detect a magnetic flux passing through the magnetic steel plate, and a surface of the magnetic steel plate by moving the magnetic field detector. From the output signal of the magnetic field detector obtained at least at two different distances from the magnetic steel sheet, and the magnetic steel sheet obtained from the value and the output signal of the magnetic flux detecting coil. An incremental magnetic permeability measuring apparatus for a magnetic steel sheet, comprising: an arithmetic unit for obtaining the incremental magnetic permeability of the magnetic steel sheet from the magnetic flux density of the magnetic flux passing through the inside.
の強さは１０-2Ｏｅ以下であることを特徴とする請求項
１、２又は３の何れかに記載の磁性鋼板の増分透磁率計
測装置。4. The incremental magnetic permeability measuring device for a magnetic steel sheet according to claim 1, wherein the strength of the magnetic field generated by the exciting coil is 10 −2 Oe or less. .
の長さと同等又はこれより大きくし、前記磁界検出器及
び磁束検出用コイルを、前記磁性鋼板の長手方向を３等
分したその中央部分内に配置し、前記磁界検出器は前記
磁性鋼板と励磁用コイルとの間の磁性鋼板側の３分の１
の空間内に配置することを特徴とする請求項１、２、３
又は４の何れかに記載の磁性鋼板の増分透磁率計測装
置。5. The length of the exciting coil is made equal to or longer than the length of the magnetic steel plate, and the magnetic field detector and the magnetic flux detecting coil are divided into three parts in the longitudinal direction of the magnetic steel plate. The magnetic field detector is arranged in a portion, and the magnetic field detector is a third of the magnetic steel sheet side between the magnetic steel sheet and the exciting coil.
It arrange | positions in the space of Claim 1, 2, 3 characterized by the above-mentioned.
Or the incremental magnetic permeability measuring apparatus of the magnetic steel plate in any one of 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6023893A JP3019714B2 (en) | 1994-02-22 | 1994-02-22 | Measuring device for incremental permeability of magnetic steel sheet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6023893A JP3019714B2 (en) | 1994-02-22 | 1994-02-22 | Measuring device for incremental permeability of magnetic steel sheet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07229955A true JPH07229955A (en) | 1995-08-29 |
| JP3019714B2 JP3019714B2 (en) | 2000-03-13 |
Family
ID=12123139
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6023893A Expired - Lifetime JP3019714B2 (en) | 1994-02-22 | 1994-02-22 | Measuring device for incremental permeability of magnetic steel sheet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3019714B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020052615A (en) * | 2000-12-26 | 2002-07-04 | 이구택 | Method for testing the permeability of Non-magnet austenitic stainless steel |
| JP2013238453A (en) * | 2012-05-14 | 2013-11-28 | Nippon Soken Inc | Magnetic sensor |
| CN109342979A (en) * | 2018-11-05 | 2019-02-15 | 镇江苏润电子科技有限公司 | Magnet steel Gauss amount detecting device and method |
| JP2020118454A (en) * | 2019-01-18 | 2020-08-06 | 日本製鉄株式会社 | Magnetic characteristics measurement system |
-
1994
- 1994-02-22 JP JP6023893A patent/JP3019714B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020052615A (en) * | 2000-12-26 | 2002-07-04 | 이구택 | Method for testing the permeability of Non-magnet austenitic stainless steel |
| JP2013238453A (en) * | 2012-05-14 | 2013-11-28 | Nippon Soken Inc | Magnetic sensor |
| CN109342979A (en) * | 2018-11-05 | 2019-02-15 | 镇江苏润电子科技有限公司 | Magnet steel Gauss amount detecting device and method |
| JP2020118454A (en) * | 2019-01-18 | 2020-08-06 | 日本製鉄株式会社 | Magnetic characteristics measurement system |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3019714B2 (en) | 2000-03-13 |
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