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JP2019138900A - Defect inspection device for steel plate and defect inspection method for steel plate - Google Patents

Defect inspection device for steel plate and defect inspection method for steel plate Download PDF

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JP2019138900A
JP2019138900A JP2019004072A JP2019004072A JP2019138900A JP 2019138900 A JP2019138900 A JP 2019138900A JP 2019004072 A JP2019004072 A JP 2019004072A JP 2019004072 A JP2019004072 A JP 2019004072A JP 2019138900 A JP2019138900 A JP 2019138900A
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steel plate
steel sheet
light source
defect inspection
defect
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JP6822494B2 (en
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貴彦 板垣
Takahiko ITAGAKI
貴彦 板垣
恒治 澤村
Koji Sawamura
恒治 澤村
腰原 敬弘
Takahiro Koshihara
敬弘 腰原
辰哉 江橋
Tatsuya Ehashi
辰哉 江橋
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JFE Steel Corp
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Abstract

To provide a defect inspection device for a steel plate and a defect inspection method for a steel plate, capable of highly accurately detecting a surface defect, even when the type of a steel plate P is changed so as to greatly change a surface property like a GA steel plate and a GI steel plate.SOLUTION: A defect inspection device for a steel plate 1 according to an embodiment of the present invention is a defect inspection device for a steel plate which irradiates the surface of the steel plate P with illumination light from a light source 2, photographs the surface image of the steel plate P irradiated with the illumination light by an imaging apparatus 3, and detects the surface defect of the steel plate P on the basis of the luminance value of the surface image and includes a gloss meter 4 which measures the glossiness of the steel plate P and a control device 5 which adjusts the position and/or angle of at least one of the light source 2 and the imaging apparatus 3 according to the glossiness of the steel plate P measured by the gloss meter 4.SELECTED DRAWING: Figure 3

Description

本発明は、鋼板の欠陥検査装置及び欠陥検査方法に関する。   The present invention relates to a steel sheet defect inspection apparatus and defect inspection method.

従来の鋼板の欠陥検査方法として、特許文献1には、鋼板の法線に対して光源と撮像装置とを同じ側に配置し、光源から鋼板に照明光を照射し、照明光の反射光を撮像装置で撮影することによって得られた鋼板の画像を所定の輝度閾値で切り出すことにより、表面欠陥を検出する方法が開示されている。特にこの方法は、合金化処理を施した合金化溶融亜鉛めっき鋼板特有の表面性状に起因する地合ノイズを抑制するため、鋼板の法線に対して光源と撮像装置とを同じ側に配置していることに特徴がある。また、特許文献2には、光源と撮像装置とを反対側に配置する正反射ないしは準正反射の光学系をとり、光沢度に応じて撮像装置の受光光量を調整するために撮像装置の位置を変えることで、入射角度を変化させる方法が開示されている。   As a conventional steel sheet defect inspection method, Patent Document 1 discloses that a light source and an imaging device are arranged on the same side with respect to a normal line of a steel plate, illuminate the steel plate from the light source, and reflect the reflected light of the illumination light. A method of detecting a surface defect by cutting out an image of a steel plate obtained by photographing with an imaging device with a predetermined luminance threshold is disclosed. In particular, in this method, the light source and the imaging device are arranged on the same side with respect to the normal line of the steel sheet in order to suppress formation noise caused by the surface properties unique to the alloyed hot-dip galvanized steel sheet. There is a feature. Japanese Patent Application Laid-Open No. 2004-228561 employs a specular or quasi-regular reflection optical system in which a light source and an imaging device are arranged on the opposite side, and the position of the imaging device to adjust the amount of light received by the imaging device in accordance with the glossiness. A method of changing the incident angle by changing the angle is disclosed.

特開2012−103017号公報JP 2012-103017 A 特開平11−248642号公報Japanese Patent Laid-Open No. 11-248642

特許文献1に記載の鋼板の欠陥検査方法では、鋼板の品種に応じて表面粗さや光沢度が変化した場合、表面欠陥からの反射光の輝度と健全部からの反射光の輝度との差が小さくなり、表面欠陥を検出できなくなることがある。具体的には、合金化処理を施した溶融亜鉛めっき鋼板(GA鋼板)と合金化処理を施していない溶融亜鉛めっき鋼板(GI鋼板)とでは表面粗さや光沢度が異なるために、固定された光源や撮像装置の配置ではドロスブツ欠陥を検出することができない。また、特許文献2には光沢度に応じて撮像装置の受光光量を調整するために入射角度を変える方法が開示されているが、光量を調整するために入射角度を変えるのみであるため、GA鋼板特有の表面性状に起因する地合ノイズを抑制できず、結果としてドロス欠陥等を検出できない。   In the defect inspection method for a steel sheet described in Patent Document 1, when the surface roughness and the glossiness change according to the type of the steel sheet, the difference between the brightness of the reflected light from the surface defect and the brightness of the reflected light from the healthy part is It may become small and surface defects cannot be detected. Specifically, the hot-dip galvanized steel sheet (GA steel sheet) subjected to the alloying treatment and the hot-dip galvanized steel sheet (GI steel sheet) not subjected to the alloying treatment were fixed because of different surface roughness and glossiness. The dross defect cannot be detected by the arrangement of the light source and the imaging device. Patent Document 2 discloses a method of changing the incident angle in order to adjust the amount of light received by the imaging device in accordance with the glossiness. However, since only the incident angle is changed in order to adjust the amount of light, the GA The formation noise caused by the surface properties peculiar to the steel sheet cannot be suppressed, and as a result, dross defects or the like cannot be detected.

本発明は、上記課題に鑑みてなされたものであって、その目的は、鋼板の品種がGA鋼板とGI鋼板のように大きく表面性状が変わるような変化をした場合であっても表面欠陥を精度よく検出可能な鋼板の欠陥検査装置及び欠陥検査方法を提供することにある。   The present invention has been made in view of the above-mentioned problems, and its purpose is to eliminate surface defects even when the type of steel sheet has undergone a large change in surface properties, such as a GA steel sheet and a GI steel sheet. An object of the present invention is to provide a defect inspection apparatus and defect inspection method for a steel sheet that can be detected with high accuracy.

本発明に係る鋼板の欠陥検査装置は、光源から鋼板の表面に照明光を照射し、照明光が照射された前記鋼板の表面画像を撮像装置により撮影し、前記表面画像の輝度値に基づいて前記鋼板の表面欠陥を検出する鋼板の欠陥検査装置であって、前記鋼板の光沢度を測定する光沢度計と、前記光沢度計によって測定された前記鋼板の光沢度に応じて前記光源及び前記撮像装置の少なくとも一方の位置及び/又は角度を調整する制御装置と、を備えることを特徴とする。   The steel sheet defect inspection apparatus according to the present invention irradiates the surface of the steel sheet with illumination light from a light source, takes a surface image of the steel sheet irradiated with the illumination light with an imaging device, and based on the luminance value of the surface image A steel sheet defect inspection apparatus for detecting surface defects of the steel sheet, a gloss meter for measuring the gloss level of the steel sheet, the light source and the light source according to the gloss level of the steel sheet measured by the gloss meter And a control device that adjusts the position and / or angle of at least one of the imaging devices.

本発明に係る鋼板の欠陥検査方法は、光源から鋼板の表面に照明光を照射し、照明光が照射された前記鋼板の表面画像を撮像装置により撮影し、前記表面画像の輝度値に基づいて前記鋼板の表面欠陥を検出する鋼板の欠陥検査方法であって、前記鋼板の光沢度を測定する測定ステップと、前記測定ステップにおいて測定された前記鋼板の光沢度に応じて前記光源及び前記撮像装置の少なくとも一方の位置及び/又は角度を調整する制御ステップと、を含むことを特徴とする。   The defect inspection method for a steel sheet according to the present invention irradiates the surface of the steel sheet with illumination light from a light source, takes a surface image of the steel sheet irradiated with the illumination light with an imaging device, and based on the luminance value of the surface image A steel plate defect inspection method for detecting a surface defect of the steel plate, wherein the measuring step of measuring the glossiness of the steel plate, and the light source and the imaging device according to the glossiness of the steel plate measured in the measuring step And a control step of adjusting the position and / or angle of at least one of the above.

本発明に係る鋼板の欠陥検査装置及び欠陥検査方法によれば、鋼板の品種がGA鋼板とGI鋼板のように大きく表面性状が変わるような変化をした場合であっても表面欠陥を精度よく検出することができる。   According to the defect inspection apparatus and defect inspection method for a steel sheet according to the present invention, surface defects can be accurately detected even when the type of the steel sheet undergoes a large change in surface properties, such as a GA steel sheet and a GI steel sheet. can do.

図1は、照明角度及びカメラ角度を変更した時のGA鋼板の微小欠陥部の検出状況の一例を示す図である。FIG. 1 is a diagram illustrating an example of a detection state of a minute defect portion of a GA steel sheet when the illumination angle and the camera angle are changed. 図2は、GI鋼板の表面画像の一例を示す図である。FIG. 2 is a diagram illustrating an example of a surface image of a GI steel plate. 図3は、本発明の一実施形態である鋼板の欠陥検査装置の構成を示す模式図である。FIG. 3 is a schematic diagram showing the configuration of a steel sheet defect inspection apparatus according to an embodiment of the present invention. 図4は、図3に示す鋼板の欠陥検査装置の変形例の構成を示す模式図である。FIG. 4 is a schematic diagram illustrating a configuration of a modification of the steel sheet defect inspection apparatus illustrated in FIG. 3. 図5は、GI鋼板の黒斑点欠陥の検出をした際のS/N比の一例を示す図である。FIG. 5 is a diagram illustrating an example of the S / N ratio when black spot defects of a GI steel sheet are detected.

本発明の発明者らは、実験によりGA鋼板及びGI鋼板の表面性状の違いを検討した。その結果、図1に示すように、GA鋼板の場合、正反射では微細欠陥を検出することが難しく、表面の反射光の微細な変化を捉えるためには後方拡散光を撮影する方法が有利であることがわかった。具体的には、図1に示す例では、照明角度αが−60〜−80°の範囲内にあり、且つ、カメラ角度βが−60〜−20°の範囲内にあるときに、GA鋼板特有の表面性状に起因する地合ノイズを抑制することができ、表面画像のS/N比≒3と他の部分より高く良好となり、精度よく欠陥を検出できていることがわかった。以上のように、GA鋼板では欠陥サンプルの法線に対して光源とカメラが同じ側に配置された場合に有利であることがわかった。これに対して、GI鋼板では、GA鋼板と同様に後方拡散光を撮影した場合、表面の光沢度が高いために照明光の多くが前方に反射し、後方拡散光が少なくなることによって表面画像が全体的に暗くなることがわかった。またその一方で、図2に示すように、GI鋼板では、ダル目(調質圧延の際にロールから転写された鋼板表面の凹凸)のエッジ部の表面画像に部分的に後方拡散光が増加して明るくなっている領域(図2において破線で囲った領域)があることがわかった。このため、同じ光学系を用いてGA鋼板及びGI鋼板の表面欠陥を検査した場合、ダル目のエッジ部を表面欠陥と認識することによって表面欠陥の過検出が多くなり、表面欠陥を精度高く検出することが困難になることがわかった。   The inventors of the present invention examined the difference in surface properties between the GA steel sheet and the GI steel sheet through experiments. As a result, as shown in FIG. 1, in the case of GA steel sheet, it is difficult to detect fine defects by regular reflection, and in order to capture minute changes in reflected light on the surface, a method of photographing back diffused light is advantageous. I found out. Specifically, in the example shown in FIG. 1, when the illumination angle α is in the range of −60 to −80 ° and the camera angle β is in the range of −60 to −20 °, the GA steel plate. It was found that the formation noise caused by the specific surface property can be suppressed, the S / N ratio of the surface image is approximately 3 and higher than other portions, and the defect can be detected with high accuracy. As described above, it was found that the GA steel plate is advantageous when the light source and the camera are arranged on the same side with respect to the normal line of the defective sample. On the other hand, in the GI steel sheet, when the back diffused light is photographed in the same manner as the GA steel sheet, since the glossiness of the surface is high, most of the illumination light is reflected forward, and the back diffused light is reduced to reduce the surface image. Turned out to be totally dark. On the other hand, as shown in FIG. 2, in the GI steel sheet, the back diffused light partially increases in the surface image of the edge part of the dull eye (the unevenness of the steel sheet surface transferred from the roll during the temper rolling). As a result, it was found that there was a bright area (area surrounded by a broken line in FIG. 2). For this reason, when surface defects of GA steel plates and GI steel plates are inspected using the same optical system, the surface defects are detected with high accuracy by recognizing the edge portions of the dull eyes as surface defects. I found it difficult to do.

以下、図3,図4を参照して、上記知見に基づき想倒された、本発明の一実施形態である鋼板の欠陥検査装置の構成について説明する。   Hereinafter, with reference to FIG. 3 and FIG. 4, a configuration of a defect inspection apparatus for a steel sheet, which is an embodiment of the present invention, conceived based on the above knowledge will be described.

図3は、本発明の一実施形態である鋼板の欠陥検査装置の構成を示す模式図である。図3に示すように、本発明の一実施形態である鋼板の欠陥検査装置1は、矢印L方向に走行する鋼板Pの表面欠陥を検査する装置であり、光源2、撮像装置3、光沢度計4、及び制御装置5を備えている。なお、図3中、符号Xは、鋼板P表面の法線を示している。   FIG. 3 is a schematic diagram showing the configuration of a steel sheet defect inspection apparatus according to an embodiment of the present invention. As shown in FIG. 3, a steel sheet defect inspection apparatus 1 according to an embodiment of the present invention is an apparatus for inspecting a surface defect of a steel sheet P traveling in the direction of an arrow L, and includes a light source 2, an imaging device 3, and a glossiness. A total 4 and a control device 5 are provided. In FIG. 3, the symbol X indicates the normal line on the surface of the steel plate P.

光源2は、ストロボ光源、LED光源、メタルハライドランプ等の光源により構成され、鋼板Pの走行方向と直交する鋼板Pの幅方向に複数配置されている。光源2は、鋼板Pの表面に照明光を照射する。なお、ライトガイドを用いて照明光の形状を鋼板Pの幅方向に細長い形状にすることが望ましい。これにより、鋼板Pの幅方向にむらのない欠陥検査を行うことができる。   The light source 2 is composed of a light source such as a strobe light source, an LED light source, and a metal halide lamp, and a plurality of light sources 2 are arranged in the width direction of the steel plate P perpendicular to the traveling direction of the steel plate P. The light source 2 irradiates the surface of the steel plate P with illumination light. In addition, it is desirable to make the shape of illumination light long and narrow in the width direction of the steel plate P using a light guide. Thereby, a defect inspection without unevenness in the width direction of the steel sheet P can be performed.

撮像装置3は、1次元のリニアアレイカメラ、2次元のエリアセンサカメラ等の撮像装置により構成され、鋼板Pの幅方向に複数配置されている。撮像装置3は、照明光が照射された鋼板Pの表面画像を撮影し、撮影された表面画像の輝度データを図示しない画像処理装置に出力する。なお、カメラとしては、CCDカメラやCMOSカメラ等を利用できるが、必ずしもこれに限定されることはない。   The imaging device 3 is configured by an imaging device such as a one-dimensional linear array camera or a two-dimensional area sensor camera, and a plurality of imaging devices 3 are arranged in the width direction of the steel plate P. The imaging device 3 captures a surface image of the steel plate P irradiated with illumination light, and outputs luminance data of the captured surface image to an image processing device (not shown). As a camera, a CCD camera, a CMOS camera, or the like can be used, but is not necessarily limited thereto.

ここで、図示しない画像処理装置は、撮像装置3から出力された表面画像の輝度データに対してシェーディング補正処理、エッジ処理、フィルタリング処理等の処理を施した後、閾値処理により欠陥候補部を2値化してラベリングする。そして、画像処理装置は、欠陥候補部の面積、長さ、幅、縦横比等の特徴量を算出し、算出された特徴量に基づいて表面欠陥の種別や等級を判定する。種別や等級が判定された表面欠陥の情報は、図示しない集計用コンピュータに送信されてコイル毎に集計され、コイル内の欠陥種、等級毎の欠陥数、欠陥密度等によってコイルの合否が判定される。   Here, an image processing device (not shown) performs processing such as shading correction processing, edge processing, filtering processing, etc. on the luminance data of the surface image output from the imaging device 3, and then adds 2 defect candidate portions by threshold processing. Price and label. Then, the image processing apparatus calculates feature amounts such as the area, length, width, and aspect ratio of the defect candidate portion, and determines the type and grade of the surface defect based on the calculated feature amounts. The information on the surface defects for which the type and grade are determined is sent to a not-shown counting computer and totaled for each coil, and the pass / fail of the coil is determined by the defect type in the coil, the number of defects for each grade, the defect density, etc. The

光沢度計4は、鋼板Pの表面の光沢度を測定し、測定された光沢度を示す電気信号を制御装置5に出力する。   The gloss meter 4 measures the gloss level of the surface of the steel sheet P and outputs an electrical signal indicating the measured gloss level to the control device 5.

制御装置5は、光沢度計4から出力された電気信号に基づいて、鋼板Pの表面に対する光源2及び撮像装置3の少なくとも一方の位置及び/又は角度を調整する。光源2及び撮像装置3の位置及び角度は、撮像装置3が後方散乱光を受光可能な位置及び角度と撮像装置3が正反射光を受光可能な位置及び角度との範囲内で調整可能となっている。   The control device 5 adjusts the position and / or angle of at least one of the light source 2 and the imaging device 3 with respect to the surface of the steel plate P based on the electrical signal output from the gloss meter 4. The positions and angles of the light source 2 and the imaging device 3 can be adjusted within the range between the position and angle at which the imaging device 3 can receive backscattered light and the position and angle at which the imaging device 3 can receive regular reflection light. ing.

このような構成を有する鋼板の欠陥検出装置1では、制御装置5が、鋼板Pの表面の光沢度に応じて鋼板Pの表面に対する光源2及び撮像装置3の少なくとも一方の位置及び/又は角度を調整するので、鋼板Pの品種がGA鋼板とGI鋼板のように大きく表面性状が変わるような変化をした場合であってもS/N比が良好な鋼板Pの表面画像を撮影して、鋼板Pの表面欠陥を精度よく検出することができる。   In the defect detection device 1 for a steel plate having such a configuration, the control device 5 determines the position and / or angle of at least one of the light source 2 and the imaging device 3 with respect to the surface of the steel plate P according to the glossiness of the surface of the steel plate P. Since the adjustment is made, the surface image of the steel sheet P with a good S / N ratio is taken even if the type of the steel sheet P has changed such as a GA steel sheet and a GI steel sheet that have a large change in surface properties. P surface defects can be detected with high accuracy.

なお、上記実施形態では、鋼板Pの表面の光沢度に応じて光源2及び撮像装置3の少なくとも一方の位置及び/又は角度を制御することとしたが、図4(a),(b)に示すように、光源2a及び光源2bの2つの光源を用意し、鋼板Pの表面の光沢度に応じて点灯する光源を切り換えてもよい。具体的には、光沢度が高い鋼板(例えばGI鋼板)を検査する場合、図4(a)に示すように、光源2aを消灯して光源2bを点灯することによって撮像装置3で正反射光を撮影する。一方、光沢度が低い鋼板(例えばGA鋼板)を検査する場合には、図4(b)に示すように、光源2aを点灯して光源2bを消灯することによって撮像装置3で後方拡散光を撮影する。これにより、鋼板Pの品種がGA鋼板とGI鋼板のように大きく表面性状が変わるような変化をした場合であっても、S/N比が良好な鋼板Pの表面画像を撮影し、鋼板Pの表面欠陥を精度よく検出することができる。   In the above embodiment, the position and / or angle of at least one of the light source 2 and the imaging device 3 is controlled in accordance with the glossiness of the surface of the steel plate P. FIGS. 4 (a) and 4 (b). As shown, two light sources, a light source 2a and a light source 2b, may be prepared and the light source to be turned on may be switched according to the glossiness of the surface of the steel plate P. Specifically, when inspecting a steel sheet with high glossiness (for example, a GI steel sheet), as shown in FIG. 4A, the light reflected on the imaging device 3 is turned off by turning off the light source 2a and turning on the light source 2b. Shoot. On the other hand, when inspecting a steel sheet with low glossiness (for example, a GA steel sheet), as shown in FIG. 4B, the imaging device 3 emits back diffused light by turning on the light source 2a and turning off the light source 2b. Take a picture. As a result, even if the type of the steel plate P has changed such as a GA steel plate and a GI steel plate with a large change in surface properties, a surface image of the steel plate P with a good S / N ratio is taken, and the steel plate P It is possible to accurately detect surface defects.

なお、複数の光源を異なる角度で配置し、鋼板Pの表面の光沢度に応じて照明光を照射する光源を複数の光源の中で切り換えるようにしてもよい。また同様に、複数の撮像装置を異なる角度で配置し、鋼板Pの表面の光沢度に応じて鋼板Pの表面の画像を撮影する撮像装置を複数の撮像装置の中で切り換えるようにしてもよい。   Note that a plurality of light sources may be arranged at different angles, and the light source that emits the illumination light may be switched among the plurality of light sources in accordance with the glossiness of the surface of the steel plate P. Similarly, a plurality of imaging devices may be arranged at different angles, and the imaging device that captures an image of the surface of the steel plate P according to the glossiness of the surface of the steel plate P may be switched among the plurality of imaging devices. .

図5は、GI鋼板において、検出対象の表面欠陥である黒斑点欠陥について光源及び撮像装置の角度を変えて検出実験を行った結果を示す図であり、表中の数字は表面画像のS/N比(N=3σ)を示している。また、図5中の領域R1は図1に示すGA鋼板の例における光源及び撮像装置の角度の好適範囲を示し、図5中の領域R2は図5に示すGI鋼板の例における光源及び撮像装置の角度の好適範囲を示す。図5に示すように、GI鋼板では、照明角度が+10〜+40°の範囲内にあり、且つ、撮像装置の角度(カメラ角度)が−10〜−50°の範囲内にあるときに表面画像のS/N比が高くなり、欠陥を良好に検出できることが確認された。特に照明角度30°及びカメラ角度30°の正反射、及びカメラ角度に対して照明角度が±10°以内の概正反射では、表面画像のS/N比が良好であることが確認された。このことから、光沢度が通常40GU以下の範囲内にあるGA鋼板を検査する際は後方拡散光で撮影する光学系を採用し、光沢度が通常50GU以上200GU以下の範囲内にあるGI鋼板を検査する際には正反射又は概正反射で撮影する光学系を採用することにより、GA鋼板及びGI鋼板のどちらについても表面欠陥を精度よく検出できることが確認された。以上のように、あらかじめ光沢度を測定することにより、適正なカメラ角度、照明角度を選択できることがわかった。   FIG. 5 is a diagram showing the results of a detection experiment performed on a GI steel sheet by changing the angles of the light source and the imaging device for black spot defects, which are surface defects to be detected, and the numbers in the table indicate the S / S of the surface image. The N ratio (N = 3σ) is shown. Further, a region R1 in FIG. 5 shows a preferable range of angles of the light source and the imaging device in the example of the GA steel plate shown in FIG. 1, and a region R2 in FIG. 5 shows the light source and the imaging device in the example of the GI steel plate shown in FIG. The preferred range of the angle is shown. As shown in FIG. 5, in the GI steel sheet, the surface image is obtained when the illumination angle is in the range of +10 to + 40 ° and the angle of the imaging device (camera angle) is in the range of −10 to −50 °. It was confirmed that the S / N ratio was high and defects could be detected well. In particular, it was confirmed that the S / N ratio of the surface image was good in the regular reflection at an illumination angle of 30 ° and a camera angle of 30 ° and the approximate regular reflection with an illumination angle within ± 10 ° with respect to the camera angle. For this reason, when inspecting GA steel sheets whose glossiness is usually in the range of 40 GU or less, an optical system for photographing with backward diffused light is used, and GI steel sheets whose glossiness is normally in the range of 50 GU or more and 200 GU or less are adopted. It was confirmed that surface defects can be detected with high accuracy in both the GA steel plate and the GI steel plate by employing an optical system for photographing with specular reflection or approximate specular reflection when inspecting. As described above, it was found that an appropriate camera angle and illumination angle can be selected by measuring the glossiness in advance.

以上、本発明者らによってなされた発明を適用した実施の形態について説明したが、本実施形態による本発明の開示の一部をなす記述及び図面により本発明は限定されることはない。すなわち、本実施形態に基づいて当業者等によりなされる他の実施の形態、実施例、及び運用技術等は全て本発明の範疇に含まれる。   The embodiment to which the invention made by the present inventors is applied has been described above, but the present invention is not limited by the description and the drawings that constitute a part of the disclosure of the present invention. That is, other embodiments, examples, operational techniques, and the like made by those skilled in the art based on this embodiment are all included in the scope of the present invention.

1 鋼板の欠陥検査装置
2,2a,2b 光源
3 撮像装置
4 光沢度計
5 制御装置
P 鋼板
DESCRIPTION OF SYMBOLS 1 Steel plate defect inspection device 2, 2a, 2b Light source 3 Imaging device 4 Gloss meter 5 Control device P Steel plate

Claims (2)

光源から鋼板の表面に照明光を照射し、照明光が照射された前記鋼板の表面画像を撮像装置により撮影し、前記表面画像の輝度値に基づいて前記鋼板の表面欠陥を検出する鋼板の欠陥検査装置であって、
前記鋼板の光沢度を測定する光沢度計と、
前記光沢度計によって測定された前記鋼板の光沢度に応じて前記光源及び前記撮像装置の少なくとも一方の位置及び/又は角度を調整する制御装置と、
を備えることを特徴とする鋼板の欠陥検査装置。
A steel plate defect in which illumination light is irradiated from the light source to the surface of the steel sheet, a surface image of the steel sheet irradiated with the illumination light is photographed by an imaging device, and a surface defect of the steel sheet is detected based on a luminance value of the surface image An inspection device,
A gloss meter for measuring the gloss of the steel sheet;
A control device that adjusts the position and / or angle of at least one of the light source and the imaging device according to the gloss level of the steel sheet measured by the gloss meter;
A defect inspection apparatus for steel sheet, comprising:
光源から鋼板の表面に照明光を照射し、照明光が照射された前記鋼板の表面画像を撮像装置により撮影し、前記表面画像の輝度値に基づいて前記鋼板の表面欠陥を検出する鋼板の欠陥検査方法であって、
前記鋼板の光沢度を測定する測定ステップと、
前記測定ステップにおいて測定された前記鋼板の光沢度に応じて前記光源及び前記撮像装置の少なくとも一方の位置及び/又は角度を調整する制御ステップと、
を含むことを特徴とする鋼板の欠陥検査方法。
A steel plate defect in which illumination light is irradiated from the light source to the surface of the steel sheet, a surface image of the steel sheet irradiated with the illumination light is photographed by an imaging device, and a surface defect of the steel sheet is detected based on a luminance value of the surface image An inspection method,
A measuring step for measuring the glossiness of the steel sheet;
A control step of adjusting the position and / or angle of at least one of the light source and the imaging device according to the glossiness of the steel sheet measured in the measurement step;
A method for inspecting a defect of a steel sheet, comprising:
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111113410A (en) * 2019-12-05 2020-05-08 珠海格力电器股份有限公司 Robot motion control method for visual adaptive detection, computer readable storage medium and robot
JP2022023825A (en) * 2020-07-27 2022-02-08 Jfeスチール株式会社 Flaw inspection apparatus
JPWO2022030083A1 (en) * 2020-08-06 2022-02-10

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111113410A (en) * 2019-12-05 2020-05-08 珠海格力电器股份有限公司 Robot motion control method for visual adaptive detection, computer readable storage medium and robot
CN111113410B (en) * 2019-12-05 2021-11-30 珠海格力电器股份有限公司 Robot motion control method for visual adaptive detection, computer readable storage medium and robot
JP2022023825A (en) * 2020-07-27 2022-02-08 Jfeスチール株式会社 Flaw inspection apparatus
JP7493163B2 (en) 2020-07-27 2024-05-31 Jfeスチール株式会社 Defect inspection device
JPWO2022030083A1 (en) * 2020-08-06 2022-02-10
WO2022030083A1 (en) * 2020-08-06 2022-02-10 Jfeスチール株式会社 Metal strip surface inspection device, surface inspection method, and manufacturing method

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