JP2008304306A - Device and method for inspecting defects - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for inspecting defects appropriately detecting defects on the surface of a band body such as a thin steel plate to be inspected for a defect, by accurately specifying the position of the edge of the band body. <P>SOLUTION: The defect-inspecting device inspects defects on the surface of the band body 1, by irradiating slit light onto an irradiated area 400 crossing the moving band body 1 in the width direction. The defect-inspecting device 100 is constituted of a lighting means 110 for irradiating the irradiated area with a first slit light, emitted in a first direction 311 inclined by a first predetermined angle of θ1 to one side of the band body in the width direction with respect to the moving direction V of the band body, and a second slit light, emitted in a second direction 321 inclined by a second predetermined angle of θ2 to the other side of the band body in the width direction, with respect to the moving direction of the band body; an imaging means 120 for imaging the reflected lights of the first and second slit lights in the irradiated area and then outputting an image of the irradiated area; and an image processing means 130 for specifying the position of both edges of the band body 1 in the width direction in the image of the irradiated area, based on the intensity of the reflected light imaged by the imaging means. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a band-shaped body wrinkle inspection apparatus and a wrinkle inspection method, and more particularly to a technique for suitably performing a wrinkle inspection by detecting the edge position of a band-shaped body with high accuracy.

  For example, in the manufacture of thin steel sheets and the like in the steel industry, one item that represents the product quality of the manufactured thin steel sheets is required to have as few wrinkles on the surface of the thin steel sheets as possible. However, for example, in the manufacturing process of a thin steel plate, if foreign matter adheres to the rolling roll of the production line, roll wrinkles may be formed on the thin steel plate due to the foreign matter. Moreover, when the rolling roll vibrates minutely, fine horizontal stripes (chatter marks) may be formed on the surface of the steel sheet due to the vibration. In addition, if the surface of the hot-rolled roll is rough, the surface scale of the thin steel sheet will not be generated uniformly, and a fine rough surface will be formed even after cold rolling. There is (scale 疵). Such a surface shape defect of a thin steel plate is collectively referred to herein as a flaw.

  Once such wrinkles occur, similar wrinkles are repeatedly generated on the surface of the thin steel sheet until the roll is replaced or the manufacturing process is improved. Such wrinkles become a factor that significantly deteriorates the product quality of the thin steel sheet.

  Therefore, development of a wrinkle inspection device for detecting wrinkles of such a thin steel plate has been made. A conventional wrinkle inspection device irradiates light on the surface of a thin steel plate to be passed in a steel plate manufacturing process, and inspects wrinkles on the surface based on an image signal obtained by imaging the reflected light with an imaging device. .

  However, in the conventional wrinkle inspection device, the thin steel plate is passed as a long strip in the production line direction, so that light is diffusely reflected at the edge of the strip or irradiated to wrinkles and dirt on the roll outside the strip. When the reflected light is reflected, the reflected light is erroneously detected as a wrinkle of the thin steel plate, so-called edge false detection occurs, and as a result, the non-defective product is judged to be defective. was there.

  Therefore, in Patent Documents 1 to 4, inventions have been developed for a wrinkle inspection device that detects wrinkles of a thin steel plate while detecting an edge portion of the thin steel plate of a belt-like body.

JP-A-8-292160 JP 2005-265825 A Japanese Patent Laid-Open No. 11-237220 JP 2002-174599 A

  However, even with the conventional wrinkle inspection devices such as the above-mentioned Patent Documents 1 to 4, the wrinkle is appropriately removed due to the meandering and vibration of the thin steel plate to be passed through, or the influence of the inspection environment such as dirt and wrinkles on the roll. The possibility of not being detected still existed. This conventional wrinkle inspection apparatus will be described more specifically with reference to FIGS.

(Conventional bag inspection device 10)
FIG. 12 is a perspective view showing a schematic configuration of a conventional wrinkle inspection device 10.
As shown in FIG. 12, a conventional wrinkle inspection device 10 includes a light source 11 that irradiates light to an inspection target and an imaging device 12 that images light reflected by the inspection target, and includes a roll 2 and a roll 3. In the meantime, the flaw of a strip-shaped inspection object (hereinafter referred to as “steel plate 1”) such as a thin steel plate to be passed is inspected.

  According to the conventional wrinkle inspection device 10, the light emitted from the light source 11 is reflected by the steel plate 1 and imaged by the imaging device 12. Therefore, when the steel plate 1 has wrinkles or the like, the brightness of the image captured by the imaging device 12 is reflected by the reflected light from the wrinkles, so that wrinkles can be detected.

  Moreover, according to the conventional wrinkle inspection apparatus 10, the light deviated from the steel plate 1 passes through the side of the steel plate 1 and is not reflected by the steel plate 1 and the rolls 2, 3 etc. It is possible to prevent light from being reflected by dirt or the like and misinterpreting the reflected light as wrinkles.

  However, when vibration occurs in the steel plate 1 in the passing plate, the light reaching the imaging device 12 changes, causing a problem that the detection signal is changed to deteriorate the inspection performance of the eyelid.

  On the other hand, since the wrinkle inspection apparatus disclosed in Patent Documents 1 and 2 inspects the wrinkles of the steel plate 1 that passes through the roll, the vibration of the steel plate 1 can be suppressed, and such wrinkle inspection performance. Can be prevented. The conventional wrinkle inspection apparatus 20 disclosed in Patent Document 1 and the conventional wrinkle inspection apparatus 30 disclosed in Patent Document 2 will be described with reference to FIGS.

(Conventional bag inspection device 20)
FIG. 13 is a perspective view showing a schematic configuration of a conventional wrinkle inspection device 20.
As shown in FIG. 13, a conventional wrinkle inspection device 20 includes a light source 21 that irradiates a steel plate 1 on a roll 4 with light such as a laser beam, and an imaging device 22 that images light reflected by the steel plate 1 and the roll 4. . Furthermore, according to the conventional wrinkle inspection apparatus 20, the roll 4 is colored so that a brightness difference is created between the reflected light of the surface of the roll 4 and the reflected light of the steel plate 1.

  According to the conventional wrinkle inspection device 20, there is a difference in brightness between the reflected light from the steel plate 1 and the reflected light from the roll 4. Therefore, in the image captured by the imaging device 22, the reflected light from the steel plate 1 is reflected. Only the intensity is emphasized, and it is possible to prevent the reflected light from the roll 4 or the like from being mistakenly recognized as a wrinkle of the steel plate 1.

  However, according to the conventional wrinkle inspection apparatus 20, since it is necessary to color, it is necessary to select the material of the roll 4 as a material which can mix a pigment etc. In other words, it is necessary to select a soft material that is easy to wear, such as urethane or rubber, instead of a hard material having wear resistance such as steel. As a result, the roll 4 may be worn out and the life of the apparatus may be shortened, and dust such as iron powder is likely to be pushed between the roll 4 and the steel plate 1, so that the steel plate is pressed. It was difficult to get rid of the possible causes.

(Conventional wrinkle inspection device 30)
FIG. 14 is a side view showing a schematic configuration of a conventional wrinkle inspection device 30.
As shown in FIG. 14, the conventional wrinkle inspection device 30 includes a light source 31 that irradiates light on the steel plate 1 on the roll 2, an imaging device 32 that images light reflected by the steel plate 1 and the roll 2, and the roll 2. And an edge detector 33 that is disposed upstream of the sheet passing direction and detects the edge of the steel plate 1. As this edge detector 33, Patent Document 3 discloses an edge detection light projector 34 and an edge detection light receiver 35 arranged with the steel plate 1 interposed therebetween.

  According to the conventional wrinkle inspection device 30, first, the edge of the steel plate 1 is detected by the edge detector 33. That is, the edge detector 33 receives light that passes through the side of the light projected from the edge detection projector 34 without being shielded by the steel plate 1 by the edge detection light receiver 35, thereby receiving the light from the steel plate 1. Edge information is detected and edge position information is generated.

  Further, the conventional wrinkle inspection device 30 irradiates light from the light source 31 to the steel plate 1 on the roll 2 on the downstream side in the sheet passing direction of the edge detector 33, and reflects the reflected light from the steel plate 1 and the roll 2 to the imaging device 32. Take an image. Then, based on the edge position information from the edge detector 33, the captured image of the imaging device 32 is processed to detect wrinkles so that the reflected light from outside the steel plate 1 is not determined to be wrinkles. Therefore, according to the conventional wrinkle inspection device 30, the outer edge of the steel plate 1 can be removed from the inspection target under appropriate conditions, and wrinkles can be detected appropriately.

  However, according to this conventional wrinkle inspection device 30, due to the limitation of the space where the device is arranged, a distance of about several meters exists between the edge detector 33 and the roll 2, while the steel plate 1 to be passed is In some cases, meanders of several to several tens of millimeters. Therefore, when the meandering of the steel plate 1 is large, there may be a difference between the edge position information by the edge detector 33 and the edge position in the image actually captured by the imaging device 32. The conventional wrinkle inspection device 30 has not yet completely eliminated the possibility that the reflected light from the edge portion is erroneously recognized as wrinkles or the edge portion becomes a dead zone.

(Measurement example using a conventional wrinkle inspection device)
On the other hand, as another wrinkle inspection device capable of detecting an edge, the above-mentioned Patent Document 4 obtains information such as the plate width of the steel plate 1 for each coil, determines an allowable range where the edge exists, There has been disclosed a wrinkle inspection apparatus capable of specifying an inspection object in an image captured by an imaging apparatus by executing a complicated process for detecting an edge position. However, as shown in FIG. 15, when there is little difference between the reception intensity of the reflected light from the roll 2 and the reception intensity of the reflected light from the steel plate 1 in the measurement result, the edge portion of the steel plate 1 is accurately recognized. It becomes difficult. This will be described below with reference to FIG.

FIG. 15 is a graph showing an example of measurement results obtained by a conventional wrinkle inspection apparatus.
The measurement results shown in FIG. 15 are reflected from, for example, the steel plate 1 to be inspected and the roll 2 outside the inspection target by projecting light from the light source 31 as in the conventional wrinkle inspection device 30 shown in FIG. The imaging result when light is imaged by the imaging device 32 is shown.

  In FIG. 15, the horizontal axis (x-axis) indicates the coordinate in the width direction of the steel sheet 1, and the vertical axis indicates the signal intensity of the reflected light imaged by the imaging device 32. More specifically, the signal intensity in the range of x = 0 to x1 indicates reflected light from the roll 2, the signal intensity in the range of x = x1 to x2 indicates reflected light from the steel plate 1, and x> The signal intensity in the range of x1 indicates the reflected light from the roll 2. That is, the positions x = x1 and x2 correspond to the edge portion of the steel plate 1.

  As shown in FIG. 15, when x = x1, an increase in signal intensity corresponding to the edge portion is measured, and in the range of x = x1 to x2 (steel plate 1), the peak A2 of the signal strength from the ridge on the steel plate 1 ~ A4 is measured. However, in the range of x = 0 to x1 (roll 2), the peak A1 of the signal intensity due to the wrinkles and dirt of the roll 2 is measured, and even in the range of x> x2 (roll 2), the wrinkles and dirt of the roll 2 are measured. The peak A5 of the signal intensity due to the above is measured.

  Therefore, in order to identify the edge of the steel plate 1 and specify the inspection range (x = x1 to x2), even if the threshold ThB is provided for the signal intensity, the edge from the edge (x = x1, x2) of the steel plate 1 Since there is little difference between the signal intensity and the intensity from the surface of the roll 2 and the peaks A1 and A5 due to wrinkles and dirt on the roll 2, the peak A1 and the like may be erroneously recognized as the edge of the steel sheet 1. There was sex. Further, when dirt or the like adheres to the vicinity of the edge portion of the steel plate 1, the signal intensity of the reflected light from the dirt may be erroneously recognized as an edge. Even with the inspection apparatus, it may be difficult to accurately recognize the edge portion of the steel plate 1.

  As described above, even with the conventional wrinkle inspection devices such as Patent Documents 1 to 4 described above, it has been possible to accurately recognize the edge of the steel plate 1 and specify the inspection range without being affected by the measurement environment. There wasn't. Therefore, in order to detect wrinkles more accurately, it is possible to detect the edge without being affected by the measurement environment such as vibration and meandering of the steel sheet 1 and more accurately determine the inspection target range for detecting wrinkles. The development of a possible sputum inspection device was expected.

  Therefore, the present invention has been made in view of the above problems, and the object of the present invention is to accurately identify the position of the edge of a strip-like body such as a thin steel plate to be inspected for scissors, The purpose is to properly detect wrinkles on the body surface.

  In order to solve the above-described problems, according to an aspect of the present invention, there is provided a wrinkle inspection apparatus that inspects wrinkles on the surface of a band by irradiating a band-shaped light to an irradiation region that crosses the moving band in the width direction. The first strip light emitted in the first direction inclined by a predetermined first angle to one side in the width direction of the strip with respect to the moving direction of the strip, and the strip in the moving direction of the strip Illuminating means for irradiating the irradiation area with the second band-like light emitted in the second direction inclined by a predetermined second angle to the other side in the width direction, and the first and second band-like lights in the irradiation area An image that identifies the position of both edges in the width direction of the band in the image of the irradiation region based on the intensity of the reflected light imaged by the imaging unit and the imaging unit that captures the reflected light of the image and outputs the image of the irradiation region A wrinkle inspection device comprising a processing means.

  According to this configuration, the first belt-shaped light and the second belt-shaped light are irradiated to the irradiation region that crosses the belt-shaped body in the width direction of the belt-shaped body by the illumination unit. At this time, since the first strip light is emitted in the first direction inclined by the first angle θ1 to one side in the width direction of the strip with respect to the moving direction of the strip, the first strip light is incident in the horizontal direction at the first angle θ1. At an angle, it enters the irradiated area. Then, since the second strip light is emitted in the second direction inclined by the second angle θ2 to the other side in the width direction of the strip with respect to the moving direction of the strip, the horizontal incident angle of the second angle θ2. Then, it enters the irradiation area. Therefore, the first strip light is scattered by the edge on one side of the strip, and the second strip light is scattered by the edge on the other side of the strip. The reflected light including the light scattered by both edges can be imaged by the imaging means. At this time, since the intensity of the reflected light imaged by the imaging means includes scattered light from both edges, the scattered light from both edges included in the intensity of the reflected light imaged by the imaging means by the image processing means. Thus, the positions of both edges of the belt-like body can be specified. Therefore, it is possible to prevent the reflected light from both edges of the belt-like body from being erroneously detected as wrinkles.

  The illuminating means includes a plurality of first optical fibers arranged in the width direction of the strip and emitting light from the light source in the first direction, and the light from the light source arranged in the width direction of the strip in the second direction. And a plurality of second optical fibers that emit light. According to this configuration, the first strip light can be emitted in the first direction by the plurality of first optical fibers arranged in the width direction, and the first optical fibers arranged in the width direction can be emitted by the plurality of second optical fibers arranged in the width direction. The second strip light can be emitted in two directions. Therefore, it is possible to irradiate the irradiation region with the first band-shaped light at the incident angle of θ1 in the horizontal direction and to irradiate the irradiation region with the second band-shaped light at the incident angle in the horizontal direction of θ2.

  The illumination unit may include a prism sheet that refracts the strip light from the light source in the first direction and the second direction to emit the first strip light and the second strip light. According to this configuration, the strip light from the light source can be refracted in the first direction by the prism sheet, and the first strip light can be emitted, and the strip light from the light source can be refracted in the second direction. The second belt-like light can be emitted. Therefore, it is possible to irradiate the irradiation region with the first band-shaped light at the incident angle of θ1 in the horizontal direction and to irradiate the irradiation region with the second band-shaped light at the incident angle in the horizontal direction of θ2.

  The illuminating means is arranged in the width direction of the band and emits the first band light in the first direction, and the first LED array arranged in the width direction of the band and emits the second band light in the second direction. 2 LED arrays. According to this configuration, the first LED array arranged in the width direction can emit the first strip light in the first direction, and the second LED array arranged in the width direction can emit the second strip in the second direction. Light can be emitted. Therefore, it is possible to irradiate the irradiation region with the first band-shaped light at the incident angle of θ1 in the horizontal direction and to irradiate the irradiation region with the second band-shaped light at the incident angle in the horizontal direction of θ2.

  In addition, while moving the band, the imaging unit images the reflected light of the first and second band lights in the irradiation region a plurality of times, and the image processing unit adds the intensities of the captured plurality of reflected lights. And based on the intensity | strength of the added reflected light, you may pinpoint the position of the both edges of the width direction of the strip | belt shaped object in the image of an irradiation area | region. According to this configuration, when the strip is moving, the imaging unit captures the reflected light from the irradiation region a plurality of times, and the image processing unit adds the intensities of the plurality of reflected lights captured. Both edges of the band can be determined from the added intensity. Therefore, it is possible to increase the intensity of light from both edges of the belt-like body, and to specify the positions of both edges more accurately and easily.

  Moreover, in order to solve the above-mentioned problem, according to another aspect of the present invention, a wrinkle inspection is performed in which a band-shaped light is irradiated to an irradiation region that traverses a moving band-shaped body in the width direction to inspect a wrinkle on the surface of the band-shaped body A first band-shaped light emitted in a first direction inclined by a predetermined first angle to one side of the width direction of the band-shaped body with respect to the moving direction of the band-shaped body; and the moving direction of the band-shaped body The second band-shaped light emitted in the second direction inclined by a predetermined second angle to the other side in the width direction of the band-shaped body is irradiated to the irradiation area, and the first band-shaped light and the second band-shaped light in the irradiation area are irradiated. The image of the reflected light is output and an image of the irradiated area is output, and the positions of both edges in the width direction of the band-like body in the image of the irradiated area are specified by predetermined image processing based on the intensity of the captured reflected light A wrinkle inspection method is provided. According to this configuration, since the intensity of the reflected light imaged in the imaging step includes the scattered light from both edges of the band-like body, the positions of both edges can be specified by the scattered light.

  Further, while moving the band, the reflected light of the first band light and the second band light in the irradiation area is imaged a plurality of times, and the intensities of the plurality of reflected light images are added, and the added reflected light intensity is added. Based on this, the positions of both edges in the width direction of the band in the image of the irradiation area may be specified.

  As described above, according to the present invention, it is possible to accurately detect the position of the edge of a band-shaped body such as a thin steel plate to be inspected for wrinkles, and to appropriately detect wrinkles on the surface of the band-shaped body.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<First Embodiment>
In view of the above problems, as a result of earnest research on a wrinkle inspection apparatus capable of detecting wrinkles while more accurately detecting edges, wrinkles according to the first embodiment of the present invention conceived by the present inventor The inspection apparatus 100 will be described with reference to FIGS.

(1. Configuration of the eyelid inspection apparatus 100)
First, with reference to FIGS. 1-3, the whole structure of the wrinkle inspection apparatus 100 which concerns on this embodiment is demonstrated. FIG. 1 is an explanatory diagram for explaining the outline of a wrinkle inspection apparatus 100 according to this embodiment. FIG. 2 is an explanatory diagram for explaining the outline of the eyelid inspection apparatus 100 according to the present embodiment from above. FIG. 3 is an explanatory diagram illustrating an outline of the eyelid inspection apparatus 100 according to the present embodiment from the side. 2 and FIGS. 4, 5, 10, and 11 to be described later, the x, y, and z axes shown in FIGS. 1 and 3 are rotated about (90-α) degrees around the x axis for convenience of explanation. The axis is shown.

  The scissors inspection device 100 inspects the scissors on the surface of the steel sheet 1 using light when the steel sheet 1, which is an example of a strip-like body to be inspected, passes over the roll 2. The inspection object of the wrinkle inspection apparatus 100 is not limited to such an example, and may be a belt-like body that passes through any belt-like shape such as paper or a resin plate.

  The wrinkle inspection device 100 can detect wrinkles without being affected by vibration of the steel plate 1 or the like by inspecting the steel plate 1 supported by the roll 2 as described above. As shown in FIGS. 1 to 3, the steel plate 1 will be described below assuming that the steel plate 1 is passed in the moving direction V and folded by the roll 2. However, the present invention is not limited to such an example, and the wrinkle inspection apparatus 100 can inspect the steel plate 1 in any state, but for example, inspects the steel plate 1 in a state supported by the roll 2 or the like. It is particularly effective in cases.

  As shown in FIGS. 1 to 3, the eyelid inspection device 100 includes an illumination device 110, an imaging device 120, an image processing device 130, and a display device 140. Hereinafter, each configuration and their arrangement will be described.

(1-1. Lighting device 110)
The illumination device 110 is an example of illumination means, and irradiates the steel plate 1 supported by the roll 2 with two strip lights having a predetermined wavelength. The position where the strip light is irradiated is referred to as an irradiation region 400. In addition, the band-shaped light refers to light that is longer in the width direction (x-axis direction in FIG. 2) of the steel plate 1 than in the moving direction V of the steel plate 1 (for example, the y-axis direction in FIG. 2). In other words, the strip-shaped light refers to, for example, light irradiated on the irradiation region 400 of the steel plate 1 across the steel plate 1 in the width direction.

  In order to irradiate the irradiation region 400 with the band-shaped light, the illumination device 110 is arranged so that the irradiation port 110 </ b> A (the portion from which the light is emitted) faces the irradiation region 400. More specifically, the illuminating device 110 is disposed so as to irradiate the band-shaped light from a direction having an inclination of the angle α upstream of the moving direction V with respect to the normal line 210 in the irradiation region 400. In other words, the illuminating device 110 is disposed on a first vertical line 220 that forms an angle α with respect to the normal 210 among lines perpendicular to the width direction of the steel plate 1 (the x-axis direction in FIG. 2). The illuminating device 110 irradiates the irradiation region 400 of the steel plate 1 with strip-shaped light so that the incident angle in the vertical direction is α. This vertical incident angle α is defined as a vertical incident angle α (see FIG. 3).

  The vertical incident angle α depends on the shape of the wrinkle to be inspected and the roughness of the surface of the steel plate 1, but is preferably set to about 15 to 70 degrees, for example. If α is set to less than 15 degrees, it is necessary to increase the optical path length in order to secure the arrangement space for the illumination device 110 and the imaging device 120, making it difficult to adjust the optical system, and if α is set to be greater than 70 degrees. , The ratio of the intensity change of the reflected light due to wrinkles is reduced, so that wrinkles are difficult to detect. Further, if the vertical incident angle α is reduced within a range of about 15 to 70 degrees, it is difficult to be adversely affected by the roughness of the steel sheet surface, and if it is increased, detection of minute irregularities is facilitated.

  As illustrated in FIGS. 1 to 3, the illumination device 110 includes a light source 111, an optical fiber bundle 112, and an optical fiber unit 113.

  The light source 111 is a strip-shaped light source that irradiates the irradiation region 400, and supplies emitted light to the optical fiber bundle 112. The light source 111 can use any light source that emits light of any wavelength, but more preferably, for example, a light source that emits near-infrared visible light so as to easily detect wrinkles on the surface of the steel plate 1. Can be used. Further, as the light source 111, for example, a fluorescent lamp, an incandescent lamp, a discharge lamp, or the like can be used. By using a fluorescent lamp, an incandescent lamp, a discharge lamp, or the like, the lighting device 110 can be easily and inexpensively created. However, it goes without saying that the present invention is not limited to such a configuration.

  The optical fiber bundle 112 propagates light emitted from the light source 111 to the optical fiber unit 113. Therefore, one end of the optical fiber bundle 112 is connected to the light source 111 and the other end is connected to a plurality of optical fibers constituting the optical fiber unit 113.

  The optical fiber unit 113 propagates the light emitted from the light source 111 through the optical fiber bundle 112 and emits the light as two strip-shaped lights. Here, the two strip-shaped lights are referred to as a first strip-shaped light and a second strip-shaped light.

  As shown in FIG. 2, the first band-shaped light is a substantially parallel band-shaped light emitted in the first direction 311 from the optical fiber unit 113. The first direction 311 is a direction inclined by θ1 from the moving direction V of the steel plate 1 to one side in the width direction. In other words, the first direction 311 is a direction inclined by a first angle θ1 (hereinafter referred to as “θ1”) in a substantially horizontal direction from the first vertical line 220 perpendicular to the irradiation region 400. That is, the first belt-like light is emitted from the optical fiber unit 113 in the first direction 311 inclined by θ1 in the substantially horizontal direction from the moving direction V of the steel plate 1. Then, the first belt-like light is irradiated to the irradiation region 400 at a horizontal incident angle inclined by θ1 from the moving direction V to one side (one edge side) in the width direction (x-axis direction) of the steel plate 1. The

  Here, the substantially horizontal direction refers to the vertical direction that is the direction of the inclination of the incident angle α with respect to the normal 210 of the light from the illumination device 110 shown in FIG. It means the direction of inclination of the incident angle in the horizontal direction. As described above, the incident angle α is referred to as a vertical incident angle, and the incident angle θ1 and an incident angle θ2 described later are referred to as a horizontal incident angle.

  As shown in FIG. 2, the second band-shaped light is a substantially parallel band-shaped light emitted in the second direction 321 from the optical fiber unit 113. The second direction 321 is a direction inclined by a second angle θ2 (hereinafter referred to as “θ2”) from the moving direction V of the steel plate 1 to the other side in the width direction. In other words, the second direction 321 is a direction inclined by θ2 in the substantially horizontal direction from the first vertical line 220 perpendicular to the irradiation region 400. That is, the first belt-like light is emitted from the optical fiber unit 113 in the first direction 311 inclined by θ1 in the substantially horizontal direction from the moving direction V of the steel plate 1. Then, the first strip-shaped light is irradiated to the irradiation region 400 at a horizontal incident angle inclined by θ2 from the moving direction V to the other side (the other edge side) in the width direction (x-axis direction) of the steel plate 1. The

  It is desirable that the horizontal incident angle θ1 of the first strip light and the horizontal incident angle θ2 of the second strip light are set substantially equal. By setting the horizontal incident angle in this way, the intensity ratio of the reflected light of the first strip light and the second strip light can be made equal. Can be easily detected.

  Further, θ1 and θ2 are preferably set within a range of about 30 degrees to 60 degrees, for example. If θ1 and θ2 are set to less than 30 degrees, the scattered light from the edge of the steel sheet 1 is reduced, making it difficult to determine the edge. If θ1 and θ2 are set to be greater than 60 degrees, chatter marks, lateral folding, etc. The intensity of the reflected light from the wrinkles extending in the width direction of the steel plate 1 is reduced, making it difficult to detect such wrinkles. Further, if θ1 and θ2 are increased within a range of about 30 to 60 degrees, the specular reflection component can be removed, and the intensity of scattered light from the edge can be increased.

The optical fiber unit 113 will be described with further reference to FIGS.
FIG. 4 is an explanatory diagram for explaining the outline of the optical fiber unit 113 according to the present embodiment. FIG. 5 is an explanatory diagram for explaining an outline of the optical fiber unit 113 according to the present embodiment from above.

  As illustrated in FIG. 4, the optical fiber unit 113 includes a plurality of first optical fibers 114 and a plurality of second optical fibers 115. A plurality of first optical fibers 114 and second optical fibers 115 are each arranged in the width direction (x-axis direction) of the steel plate 1, and the arrangement of the first optical fibers 114 and the arrangement of the second optical fibers 115 are alternately performed. They are stacked in the z-axis direction. Then, as shown in FIG. 5, the first optical fibers 114 are arranged with an inclination of θ1 in the width direction with respect to the first vertical line 220, respectively, and emit light in the first direction 311. 115 are arranged with an inclination of θ 2 in the width direction with respect to the first vertical line 220, respectively, and emit light in the second direction 321.

  With such a configuration, the first optical fiber 114 can emit the first band-like light in the first direction 311 inclined by θ1 to one side in the width direction (x-axis direction) from the moving method V of the steel plate 1, The second optical fiber 115 can emit the second band-like light in the second direction 321 inclined by θ2 from the moving method V of the steel sheet 1 to the other side in the width direction (x-axis direction). And such an optical fiber unit 113 can make the position where two strip | belt-shaped light is radiate | emitted substantially the same. That is, the first strip light and the second strip light can be superimposed and emitted. Therefore, since the optical path of the first strip light and the optical path of the second strip light can be in the same plane, the vertical angle of the reflected light varies depending on the optical path difference in the vertical direction and the difference in the optical path direction. Can be prevented. Thus, since the difference in the angle of the reflected light in the vertical direction can be reduced and the reflected light other than the eyelids and edges can be propagated in the same plane, the reflected light from the first strip light and the second strip light can be transmitted. The intensity ratio with the reflected light can be made substantially constant, and edge determination and wrinkle detection can be facilitated.

  On the other hand, if there is a vertical optical path difference between the first strip light and the second strip light, the imaging device 120 images both the reflected light of the first strip light and the reflected light of the second strip light. This makes it difficult to determine the edge. However, by using the optical fiber unit 113 described above, the wrinkle inspection apparatus 100 according to the present embodiment can determine the edge. However, the illuminating device 110 is not limited to such an example, and for example, an illuminating device such as a second embodiment and a third embodiment described later can be used. Any illumination device that can similarly irradiate the second strip light can be used.

(1-2. Imaging Device 120)
Reference is again made to FIGS.
The imaging device 120 is an example of an imaging unit, and images reflected light that is reflected from the irradiation region 400 of the steel plate 1 and the roll 2 by the first strip light and the second strip light emitted from the illumination device 110. In order to image the reflected light, the imaging device 120 is arranged so that the incident port 120A for reflected light (for example, the lens or the like when the imaging device 120 includes a lens) faces the irradiation region 400. . More specifically, the imaging device 120 is arranged so as to capture the reflected light in a direction having an inclination of the angle β on the downstream side of the moving direction V with respect to the normal line 210 in the irradiation region 400. In other words, the imaging device 120 is disposed on the second vertical line 230 that forms an angle β with respect to the normal 210 among the lines perpendicular to the irradiation region 400. And the imaging device 120 images the reflected light reflected on the irradiation area 400 of the steel plate 1 and the roll 2 on the second vertical line 230. Thereafter, the imaging device 120 outputs the captured image of the irradiation region 400 to the image processing device 130.

  This angle β is preferably set so as to satisfy a range of ± 5 degrees with respect to the vertical incident angle α. If β deviates from this range, the intensity of the reflected light from the surface of the steel plate 1 cannot be imaged properly, and soot detection becomes difficult.

  As the imaging device 120, any imaging device capable of imaging reflected light and outputting the intensity of the reflected light as data to the image processing device 130 can be used. A case of being constituted by an image pickup device such as a CCD or CMOS will be described. In addition, the imaging device 120 may include a predetermined lens system in order to facilitate imaging with the imaging element and appropriately capture reflected light.

  1 to 3 show one imaging device 120 for convenience of explanation, a plurality of imaging devices 120 may be arranged in parallel in the width direction (x-axis direction) of the steel plate 1. Thus, by using a plurality of imaging devices 120, it is possible to improve the resolution of wrinkle detection with respect to the inspection width.

(1-3. Image Processing Device 130)
The image processing device 130 is an example of an image processing unit, and an image of the irradiation region 400 picked up by the imaging device 120 is input. The image of the irradiation region 400 is subjected to predetermined image processing, and the surface of the steel plate 1 is processed. Detects wrinkles. At this time, the captured image includes not only the intensity of the reflected light from the irradiation area 400 of the steel plate 1 but also the intensity of the reflected light from the irradiation area 400 of the roll 2. Therefore, the image processing apparatus 130 determines the edge of the steel plate 1 in the image of the irradiation region 400 based on the input image, and from the inspection target range in which the wrinkle is to be inspected from the determined edge, that is, from the steel plate 1. The reflected light is discriminated. Then, the image processing device 130 detects wrinkles on the surface of the steel plate 1 based on the reflected light from the steel plate 1. Thereafter, the image processing apparatus 130 outputs the detected wrinkle information and the image captured by the imaging apparatus 120 to the display apparatus 140.

The configuration of the image processing apparatus 130 will be described with reference to FIG.
FIG. 6 is an explanatory diagram for explaining the outline of the image processing apparatus 130 according to the present embodiment. As illustrated in FIG. 6, the image processing apparatus 130 includes an image acquisition unit 1301, an addition processing unit 1303, an average processing unit 1305, a differentiation processing unit 1307, an edge determination unit 1309, a storage unit 1311, and a shading correction. A unit 1313, a cocoon candidate extraction unit 1315, a cocoon determination unit 1317, and an output unit 1319.

  The image acquisition unit 1301 acquires an image of the irradiation region 400 imaged by the imaging device 120 and outputs the acquired image to the addition processing unit 1303 and the shading correction unit 1313. The addition processing unit 1303 adds the intensity of the reflected light captured to the plurality of captured images, and outputs the added intensity to the average processing unit 1305. In addition, the addition process part 1303 can make easy the detection of the edge of the steel plate 1 by adding about 2-5 images, for example.

  The average processing unit 1305 averages the intensity of the reflected light added by the addition processing unit 1303 and outputs the averaged intensity of the reflected light to the differentiation processing unit 1307. More specifically, the averaging processing unit 1305 can perform averaging by dividing the intensity of the added reflected light by the number of added images, for example.

  The differentiation processing unit 1307 differentiates the intensity of the reflected light averaged by the averaging processing unit 1305 and outputs the intensity of the reflected light subjected to the differentiation process to the edge determination unit 1309. Thus, the edge of the steel plate 1 can be further easily detected by differentiating the intensity of the reflected light.

  The edge determination unit 1309 determines the edge of the steel plate 1 from the intensity of the reflected light that has been subjected to differentiation processing by the differentiation processing unit 1307, and identifies the position of the edge. At this time, the edge determination unit 1309 acquires a predetermined threshold value predetermined in the storage unit 1311, determines an edge based on the threshold value, and specifies the position of the edge.

  For example, the image processing apparatus 130 further includes an input / output unit (not shown), and the storage unit 1311 receives this predetermined threshold value and other threshold values for wrinkle determination described later from the input / output unit (not shown) or the like. Information necessary for determining the bag or the wrinkle may be received and stored in advance, and the information stored in the storage unit 1311 may be appropriately changed via the input / output unit. Then, the edge determination unit 1309 detects the edge position of the steel plate 1 and outputs the edge position information to the shading correction unit 1313 and the wrinkle candidate extraction unit 1315.

  The shading correction unit 1313 acquires the image captured by the image acquisition unit 1301 and the position of the edge of the steel sheet 1 determined by the edge determination unit 1309. Then, the shading correction unit 1313 averages the intensity of the reflected light between the edges of the steel plate 1 in the image by performing shading correction, and outputs the image subjected to the shading correction to the eyelid candidate extraction unit 1315. The shading correction is a process for correcting unevenness of brightness due to the characteristics of the optical system and the imaging system so that the captured image becomes a uniform brightness (intensity) image. Various methods can be used.

  The wrinkle candidate extraction unit 1315 and the wrinkle determination unit 1317 detect wrinkles on the surface of the steel plate 1. For this purpose, the eyelid candidate extraction unit 1315 acquires the edge position determined by the edge determination unit 1309 and the image subjected to the shading correction by the shading correction unit 1313. Then, the wrinkle candidate extraction unit 1315 identifies the reflected light of the wrinkle from the intensity of the reflected light between the edges of the steel plate 1 in the shading-corrected image and extracts it as a wrinkle candidate. Thereafter, wrinkle candidate extraction unit 1315 outputs wrinkle candidate information and the shading-corrected image to wrinkle determination unit 1317.

  At this time, the wrinkle candidate extraction unit 1315 may detect, for example, a sudden increase or decrease in strength and extract it as a wrinkle candidate on the surface of the steel sheet 1, or detect a peak from a profile of a change in strength, You may extract as a wrinkle candidate of the surface of the steel plate 1. FIG. Then, wrinkle candidate extraction unit 1315 may output the position of the wrinkle candidate and the intensity of reflected light around this position to wrinkle determination unit 1317 as information on the wrinkle candidate, for example.

  The wrinkle determination unit 1317 acquires information on the wrinkle candidate and the shading-corrected image from the wrinkle candidate extraction unit 1315, and determines whether or not the wrinkle candidate is a harmful wrinkle and the type of the wrinkle. At this time, the wrinkle determination unit 1317 acquires information necessary for determining another predetermined threshold value or wrinkle predetermined in the storage unit 1311, and the wrinkle candidate is harmful based on the threshold value and the information. It is determined whether or not it is a bag and the type of bag. Then, wrinkle determination unit 1317 outputs information of the determination result and the image subjected to shading correction to output unit 1319. Note that the determination result information includes data such as the type, position, size, and degree of harmfulness of the eyelids.

  In this way, by detecting the wrinkles after determining the wrinkle candidates, the reflected light from the wrinkles that is acceptable in terms of manufacturing quality and luminance unevenness due to the characteristics of the optical system and the imaging system that cannot be corrected by the shading correction are eliminated. , And can be determined as a bag.

  The output unit 1319 obtains the information on the wrinkle determination result and the shading-corrected image from the wrinkle determination unit 1317, superimposes the information on the wrinkle determination result on the shading-corrected image, and outputs it to the display device 140 and the like. To do. At this time, for example, the output unit 1319 may mark the position of the eyelid or color the intensity of the eyelid so that the position of the eyelid can be recognized in this image. Further, the output unit 1319 may output a predetermined warning display superimposed on an image, for example, when there is a wrinkle determined to be harmful, or may output a warning sound at the same time.

  As described above, each component of the image processing device 130 has been described. The image processing device 130 is configured by, for example, a computer that realizes the functions of the above-described components, and includes an arithmetic device such as a CPU (Central Processing Unit), and the like. A storage device may be provided. Further, the storage device may be, for example, a magnetic storage device such as a hard disk, an optical storage device, a magneto-optical storage device, or a semiconductor memory such as a ROM (Read Only Memory) or a RAM (Radom Access Memory). Each component included in the image processing device 130 is configured to realize its function by the CPU and the storage device using the program recorded in the storage device. Alternatively, it may be configured by dedicated hardware.

(1-4. Display device 140)
The display device 140 acquires an image on which the information on the determination result of the eyelid is superimposed from the image processing device 130 and displays the image.
The configuration of the eyelid inspection apparatus 100 has been described above.

(2. Operation and measurement example of the eyelid inspection apparatus 100)
Next, operations and measurement examples of the eyelid inspection apparatus 100 will be described with reference to FIGS. FIG. 7 is an explanatory diagram for explaining the operation of the eyelid inspection apparatus 100 according to the present embodiment. 8 and 9 are graphs showing measurement examples of the eyelid inspection apparatus 100 according to the present embodiment.

(2-1. Illumination step S101 and imaging step S103)
First, the illumination device 110 irradiates the irradiation area 400 of the steel plate 1 with the first band light and the second band light (illumination step, S101). Then, the imaging device 120 captures the reflected light in the irradiation region 400 of the first strip light and the second strip light (imaging step, S103).

The flow of light at this time will be described in detail with reference to FIGS. 1 to 3 again.
As shown in FIG. 2, the first strip light is tilted by θ1 in the substantially horizontal direction from the moving direction V of the steel sheet 1, and is emitted in a first direction 311 where the incident angle in the vertical direction is α as shown in FIG. More specifically, as shown in FIG. 2, the first parallel light 315 emitted from the position L1 of the optical fiber unit 113 propagates in a direction parallel to the first direction 311 and is emitted from the position L2. The first parallel light propagates in the first direction 311, and the first parallel light 312 emitted from the position L 3 propagates in a direction parallel to the first direction 311. That is, the first parallel light between the first parallel light 315 and the first parallel light 312 emitted from between the position L1 and the position L3 of the optical fiber unit 113 is the first strip light in the first direction 311. Propagate.

  On the other hand, the second parallel light is emitted in the second direction 321 in which the inclination angle θ2 is substantially horizontal from the moving direction V of the steel plate 1 as shown in FIG. 2 and the vertical incident angle is α as shown in FIG. The More specifically, as shown in FIG. 2, the second parallel light 322 emitted from the position L1 of the optical fiber unit 113 propagates in a direction parallel to the second direction 321 and is emitted from the position L2. The second parallel light propagates in the second direction 321 and the second parallel light 325 emitted from the position L3 propagates in a direction parallel to the first direction 311. That is, the second parallel light between the second parallel light 322 and the second parallel light 325 emitted from between the position L1 and the position L3 of the optical fiber unit 113 is the second strip light in the second direction 321. Propagate.

  Then, the first strip light and the second strip light are reflected on the surface (x1 to x2) of the steel plate 1 in the irradiation region 400, and a part of the reflected light propagates toward the imaging device 120. At the same time, the first strip light and the second strip light are reflected by the surface of the roll 2 in the irradiation region 400, and a part of the reflected light propagates toward the imaging device 120.

  That is, as shown in FIG. 1, the first parallel light 312 propagating in the first direction 311 is reflected at the position x3 of the irradiation region 400 and propagates in the direction of the imaging device 120 as reflected light 313. The second parallel light 322 propagating in the second direction 321 is reflected at the position x0 of the irradiation region 400 and propagates in the direction of the imaging device 120 as reflected light 323. The first strip light and the second strip light are similarly reflected at the irradiation region 400 and propagated in the direction of the imaging device 120 as reflected light. As a result, most of the reflected light of the first strip light or the second strip light between x0 and x3 on the irradiation region 400 propagates in the direction of the imaging device 120. Then, the reflected light propagated in the direction of the imaging device 120 reaches the imaging device 120 and is captured as an image. The imaged light includes scattered light from the ridges on the surface of the steel plate 1.

  At this time, since the first strip light propagates in the direction inclined in the first edge direction (first direction 311) of the steel plate 1 located at the position x2, it is scattered at the first edge, and the scattered light is imaged. It can propagate in the direction of the device 120. And since the 2nd strip | belt-shaped light propagates in the direction (2nd direction 321) inclined in the 2nd edge direction of the steel plate 1 located in the position x1, it is scattered in a 2nd edge and the said scattered light is an imaging device. It can propagate in 120 directions. Therefore, the image captured by the imaging device 120 can include more scattered light from the first edge or the second edge. As a result, the edge of the steel plate 1 can be easily determined.

An example of scattered light from the first edge and the second edge is shown in FIG.
8A shows the signal intensity obtained by imaging the reflected light by the first band light, FIG. 8B shows the signal intensity obtained by imaging the reflected light by the second band light, and FIG. 8C shows the first intensity. The signal intensity which imaged the reflected light by strip | belt-shaped light and 2nd strip | belt-shaped light is shown.

  In FIG. 8, the horizontal axis (x axis) indicates the coordinate in the width direction of the steel sheet 1, and the vertical axis indicates the signal intensity of the reflected light imaged by the imaging device 120. More specifically, the signal intensity in the range of x = 0 to x1 indicates reflected light from the roll 2, the signal intensity in the range of x = x1 to x2 indicates reflected light from the steel plate 1, and x> The signal intensity in the range of x1 indicates the reflected light from the roll 2. That is, the positions x = x1 and x2 correspond to the edge portion of the steel plate 1. The graph axes and the like are the same in FIG.

  As shown in FIG. 8A, at x = x2, the peak E2 of the signal intensity due to the scattered light of the first strip light at the first edge of the steel plate 1 is measured. And as shown to (B), the peak E1 of the signal strength by the scattered light of the 2nd strip | belt-shaped light in the 2nd edge of the steel plate 1 is observed in x = x1. The signal strengths of the peaks E1 and E2 are larger than the signal strength peaks A1 to A5 due to wrinkles on the surface of the steel plate 1 or wrinkles on the roll 2.

  Further, as shown in FIG. 8C, since the image captured by the imaging device 120 includes both the first strip light and the second strip light, the signal intensity of (A) and the signal of (B). It is a value obtained by adding the intensity. Therefore, since the peak E2 of the scattered light from the first edge and the peak E3 of the scattered light from the second edge are larger than the other peaks A1 to A5, the position of the edge of the steel plate 1 can be easily determined. Can do.

The light flow has been described in detail above.
As shown in FIG. 7, the above-described imaging is performed a plurality of times, and the above-described illumination and imaging are repeatedly performed until the number of images to be captured becomes n or more (S105). After the number of captured images reaches n, the following processing is performed on the n captured images.

(2-2. Addition processing step S107, Average processing step S109)
The plurality of captured images are added by the addition processing unit 1303 (S107) and averaged by the average processing unit 1305 (S109). An example of the added and averaged image is shown in FIG. FIG. 9 shows an example of an image obtained by adding and averaging the image shown in FIG. 8C and another captured image.

  The scattered light from the edge of the steel plate 1 is captured in all of the plurality of images, whereas the reflected light from the wrinkles and dirt is the predetermined image because the steel plate 1 moves in the moving direction V. It can only be captured. Therefore, as shown in FIG. 9, the signal intensities E1 and E2 from the edge do not change much compared to (C) in FIG. 8, whereas the signal intensities A1 to A5 from other wrinkles and dirt are Compared with FIG. 8C, it decreases overall. Therefore, by performing the addition process and the average process in this way, it is possible to easily determine the edge in the subsequent process.

(2-3. Differential processing step S111)
The added and averaged image may be subjected to differentiation processing by the differentiation processing unit 1307 (S111). By differentiating the intensity in this way, the change in intensity can be emphasized, so that the edge can be detected more easily.

(2-4. Edge determination step S113)
The edge determination unit 1309 determines an edge from the signal intensity of the differentiated image, and specifies the position of the edge (S113). More specifically, for example, as illustrated in FIG. 9, the edge determination unit 1309 uses a predetermined threshold ThA stored in the storage unit 1311 to determine that the signal intensity exceeding the threshold ThA is an edge. Then, the position of the edge may be specified. At this time, since the addition process and the averaging process are performed, the intensity difference between the threshold ThA and the other peaks A1 to A5 can be made larger than the intensity difference shown in FIG. Therefore, it is possible to prevent the edge from being erroneously determined by imaging relatively strong reflected light from the ridges of the steel plate 1 or the roll 2. For convenience of explanation, FIG. 9 shows an example in which an edge is determined based on a threshold value ThA for an image before being subjected to differentiation processing, but the edge is also determined by setting a predetermined threshold value in the case of differentiation processing. can do. Since the edge determination after the differentiation process is performed in the same manner, it is omitted here.

(2-5. Shading correction step S115)
Then, the shading correction unit 1313 performs shading correction on the signal intensity between the positions of both edges (for example, x = x1 to x2) in the image captured by the imaging device 120 (for example, FIG. 8) (S115). ). By performing the shading correction in this manner, luminance unevenness due to the characteristics of the optical system and the imaging system can be corrected, so that detection of wrinkles can be facilitated in subsequent processing.

  Next, in the wrinkle detection step, wrinkles on the surface of the steel plate 1 are detected from the shading-corrected image. This wrinkle detection step includes the following wrinkle candidate extraction step S117 and wrinkle determination step S119.

(2-6. Candidate candidate extraction step S117)
The wrinkle candidate extraction unit 1315 extracts the wrinkle candidate of the steel sheet 1 from the shading-corrected image (S117). At this time, the wrinkle candidate extraction unit 1315 extracts wrinkle candidates for the signal strength between edges (for example, x = x1 to x2). That is, for example, as shown in FIG. 8C, the wrinkle candidate extracting unit 1315 can extract the signal intensity peaks A2 to A4 and the like as the wrinkle candidates on the surface of the steel sheet 1, and the roll 2 It is possible to prevent the peaks A1, A5, and the like due to wrinkles and dirt from being erroneously extracted as being wrinkle candidates.

(2-7. Wrinkle determination step S119, display step S121)
The wrinkle determination unit 1317 determines whether the wrinkle candidate is a harmful wrinkle and the type of the wrinkle (S119). Then, the output unit 1319 superimposes and outputs the determination result information and the captured image, and the display device 140 displays the image on which the determination result information is superimposed (S121).

(3. Effects of the eyelid inspection apparatus 100)
The configuration, operation, and measurement example of the wrinkle inspection apparatus 100 according to the present embodiment have been described above.
According to the wrinkle inspection device 100, the first strip light and the second strip light are irradiated on the steel plate 1 with the first strip light propagating in the first direction 311 and the second strip light propagating in the second direction 321. Since the reflected light is imaged, the intensity of scattered light from both edges of the steel plate 1 can be increased. Therefore, it is possible to easily determine the edge of the steel plate 1 and, as a result, it is possible to specify a range in which wrinkles are detected, thereby preventing the wrinkles and dirt of the roll 2 from being erroneously detected as wrinkles. It is possible to reliably detect wrinkles on the surface of the steel plate 1.

  Moreover, in order to detect the wrinkles on the surface of the steel plate 1 by irradiating the steel strip 1 on the roll 2 with the first strip light and the second strip light and determining the edge of the steel plate 1 from the same reflected light, the steel plate 1 is detected. It is possible to prevent the inspection performance of the wrinkles from being deteriorated due to meandering, vibration, or the like.

  In addition, since the first band-shaped light and the second band-shaped light can be superimposed and irradiated by the optical fiber unit 113, reflection reflected by an optical path difference or an incident angle difference between the first band-shaped light and the second band-shaped light. It is possible to prevent the light intensity from changing. Therefore, the scattered light from both edges of the steel plate 1 can be imaged.

  Then, in order to add a plurality of captured images by the addition processing unit 1303, signal intensity (for example, E1, E2, etc.) due to scattered light from the edge of the steel plate 1, wrinkles of the steel plate 1, wrinkles of the roll 2, etc. The difference from the signal intensity (for example, A1 to A5, etc.) can be increased. Therefore, it is possible to prevent the signal intensity from the wrinkles of the steel plate 1 or the wrinkles of the roll 2 from being erroneously determined as the edge of the steel plate 1.

  Furthermore, since the 1st strip | belt-shaped light and the 2nd strip | belt-shaped light are irradiated from the diagonal direction by the illuminating device 110, the linear wrinkles etc. which extend in the moving direction V of the steel plate 1 can be detected effectively. In addition, since band-like light is emitted from the two directions of the first direction 311 and the second direction 321, it is possible to effectively detect wrinkles that are difficult to find depending on the light irradiation direction.

Second Embodiment
Next, a wrinkle inspection apparatus according to a second embodiment of the present invention will be described with reference to FIG.
FIG. 10 is an explanatory diagram illustrating an outline of the illumination device 510 included in the eyelid inspection apparatus according to the present embodiment. The eyelid inspection apparatus according to the present embodiment includes an illumination apparatus 510 instead of the illumination apparatus 110 among the structures included in the eyelid inspection apparatus 100 according to the first embodiment, and the other structures are the same. Therefore, below, the illuminating device 510 is demonstrated.

  The illumination device 510 included in the eyelid inspection device according to the present embodiment includes a light source 511 and a prism sheet 512 as shown in FIG.

  The light source 511 is a light source of band light that irradiates the irradiation region 400 as shown in FIG. 5A, and irradiates the prism sheet 512 with band light of parallel light that is long in the x-axis direction. The light source 511 can use a light source that emits light of any wavelength, but more preferably, a light source that emits near-infrared visible light so as to easily detect wrinkles on the surface of the steel plate 1. can do. As the light source 511, a fluorescent lamp, an incandescent lamp, a discharge lamp, or the like can be used. By using a fluorescent lamp, an incandescent lamp, a discharge lamp, or the like, the lighting device 510 can be easily and inexpensively manufactured. However, it goes without saying that the present invention is not limited to such a configuration.

  As shown in (A), the prism sheet 512 is irradiated with band-shaped light from a light source 511, and the band-shaped light is irradiated in the width direction (x-axis direction) with respect to the moving direction V (first vertical line 220) of the steel sheet 1. The light is refracted in a first direction 311 inclined by θ1 on one side and a second direction 321 inclined by θ2 on the other side in the width direction (x-axis direction). Then, the prism sheet 512 irradiates the irradiation region 400 with strip-shaped light (first strip-shaped light) refracted in the first direction 311 and strip-shaped light (second strip-shaped light) refracted in the second direction 321.

  For this purpose, the prism sheet 512 is formed in the shape shown in FIGS. (B) shows a plane when the prism sheet 512 is viewed in the y-axis direction, (C) is a cross-sectional view of the prism sheet 512 shown in (B), taken along line BB, and (D) is ( It is sectional drawing by CC line of the prism sheet 512 shown to B).

  The prism sheet 512 is formed longer in the x-axis direction than the z-axis direction, as shown in (B), and includes a first saw-shaped prism 512B shown in (C) and a second saw-shaped prism 512C shown in (D). Are alternately formed in the z-axis direction. The first saw-shaped prism 512B shown in (C) has a prism angle φ1, and the second saw-shaped prism 512C shown in (D) has a prism angle φ2. The prism angle φ1 is set corresponding to the emission angle θ1 of the first band light, and the prism angle φ2 is set corresponding to the emission angle θ2 of the second band light.

  The prism sheet 512 having such a configuration can refract the strip light from the light source 511 in the first direction 311 and the second direction 321 according to Snell's law.

  According to the present embodiment, in addition to the effects exhibited by the eyelid inspection apparatus 100 according to the first embodiment, the illumination apparatus 510 can be easily and inexpensively used by using the illumination apparatus 510 having the above-described configuration. Can be created.

<Third Embodiment>
Furthermore, with reference to FIG. 11, a wrinkle inspection apparatus according to a third embodiment of the present invention will be described.
FIG. 11 is an explanatory diagram for explaining an outline of the illumination device 610 included in the eyelid inspection device according to the present embodiment. The eyelid inspection apparatus according to the present embodiment includes an illumination apparatus 610 instead of the illumination apparatus 110 among the structures included in the eyelid inspection apparatus 100 according to the first embodiment, and the other structures are the same. Therefore, the lighting device 610 will be described below.

  As shown in FIG. 11, the illumination device 610 included in the wrinkle inspection device according to the present embodiment includes a first LED (light emitting diode) 611 and a second LED 612.

  The first LED 611 is disposed in the same manner as the first optical fiber 114 of the optical fiber unit 113 of the first embodiment, and the second LED 612 is disposed in the same manner as the second optical fiber 115. As shown in FIG. 11, a plurality of first LEDs 611 are arranged in an array in the x-axis direction to form a first LED array, and a plurality of second LEDs 612 are arranged in an array in the x-axis direction to form a second LED array. . Then, the first LED array and the second LED array are alternately stacked in the z-axis direction.

  Further, as shown in FIG. 11, each of the first LEDs 611 emits light in a first direction 311 inclined by θ1 to one side in the width direction (x-axis direction) from the moving direction V (first vertical line 220) of the steel plate 1. Each of the second LEDs 612 irradiates light in a second direction 321 inclined by θ2 from the moving direction V (first vertical line 220) of the steel plate 1 to the other side in the width direction (x-axis direction). Are arranged as follows.

  With this configuration, the first LED array irradiates the first strip light in the first direction 311, and the second LED array irradiates the second strip light in the second direction 321.

  The lighting device 610 includes a predetermined drive board and the like for driving the first LED 611 and the second LED 612. Since such an LED is driven by a general configuration, detailed description thereof is omitted here. .

  According to the present embodiment, in addition to the effect exhibited by the eyelid inspection apparatus 100 according to the first embodiment, by using the illumination device 610 having the above configuration, the first strip light and the second strip light can be obtained. Each parallelism can be improved. Moreover, the length of the 1st strip | belt-shaped light irradiated to the irradiation area | region 400 and the 2nd strip | belt-shaped light can be adjusted by driving several LED each separately. Therefore, when information such as the width of the steel plate 1 is acquired, the length of the first strip light and the second strip light is shortened by the amount irradiated to the roll 2 to reduce excessive reflected light from the roll 2. can do.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above embodiment, the eyelid inspection apparatus includes an illumination device, an imaging device, an image processing device, and a display device, but may further include a higher-level control device. In other words, in this case, the illumination of the illumination device, the imaging of the imaging device, the operation of the image processing device, and the display of the display device may be controlled by the control device. In addition, the control device acquires information such as the width and material of the steel plate 1, adjusts the length of the strip light of the lighting device, changes the number of images captured by the imaging device, and outputs this information to the image processing device. May be. Then, the image processing apparatus may perform the above operation using this information. Such a control device may be formed integrally with the image processing device.

  Moreover, the illuminating devices 110, 510, and 610 in the embodiment may include a condensing lens such as a rod lens. In this case, for example, the illumination device 110 may include a condensing lens at the light irradiation port 110 </ b> A, and the illumination device 510 collects light between the light source 511 and the prism sheet 512 or on the exit surface of the prism sheet 512. A lens may be provided, and the lighting device 610 may include a condensing lens at the light irradiation port. Thus, by providing a condensing lens, the condensing property of each of the first band-shaped light and the second band-shaped light can be improved, and the parallelism can be improved. And by improving parallelism in this way, the intensity | strength of the scattered light from the edge of the steel plate 1 and the reflected light from the wrinkle of the surface of the steel plate 1 can be strengthened.

  In the above embodiment, the horizontal incident angle θ1 of the first strip light and the horizontal incident angle θ2 of the second strip light are set to be approximately equal. However, the present invention is not limited to this example. It is not necessarily equal to θ2. As described above, since the coincidence between θ1 and θ2 is not required, the optical system of the illumination device can be easily adjusted.

  In the above-described embodiment, the image processing apparatus 130 determines the wrinkle through predetermined image processing such as the addition processing step S107 to the wrinkle determination step S119, and includes an image processing unit 1301 to an output unit 1319 for that purpose. However, the image processing for determining this wrinkle is not limited to such an example. The image processing performed by the image processing apparatus 130 can be configured in any way as long as it can determine wrinkles, and the configuration of the image processing apparatus 130 can be changed for that purpose.

  For example, the image processing apparatus 130 includes the addition processing unit 1303 and the average processing unit 1305. However, the image processing apparatus 130 is not limited to this example, and the addition processing unit 1303 and the average processing unit 1305 may not be provided. In this case, the edge of the steel plate 1 may be determined by performing subsequent processing based on the image acquired by the image acquisition unit 1301 to detect wrinkles on the surface of the steel plate 1.

  For example, in the above-described embodiment, the image processing apparatus 130 includes the average processing unit 1305. However, the image processing apparatus 130 is not limited to this example, and the average processing unit 1305 may not be included. In this case, the edge of the steel plate 1 may be determined by performing subsequent processing based on the image added by the addition processing unit 1303, and the wrinkles on the surface of the steel plate 1 may be determined.

  For example, in the above-described embodiment, the image processing apparatus 130 includes the differentiation processing unit 1307. However, the image processing device 130 is not limited to such an example, and may not include the differentiation processing unit 1307. In this case, based on the image added by the addition processing unit 1303 and averaged by the average processing unit 1305, the subsequent processing is performed to determine the edge of the steel plate 1 and to determine the surface wrinkles of the steel plate 1. May be.

  For example, in the above-described embodiment, the image processing apparatus 130 includes the shading correction unit 1313. However, the image processing apparatus 130 is not limited to this example, and the shading correction unit 1313 may not be provided. In this case, even if the surface of the steel plate 1 is determined by performing subsequent processing based on the image acquired by the image acquisition unit 1301 and the edge of the steel plate 1 determined by the edge determination unit 1309. Good.

  In the above embodiment, the steel plate 1 is passed in the moving direction V. However, the present invention is not limited to this example, and the present invention can also be applied to the stopped steel plate 1. In this case, it is also possible to measure by moving the illumination means and the imaging means relative to the steel plate 1.

It is explanatory drawing explaining the outline of the wrinkle inspection apparatus which concerns on 1st Embodiment of this invention. It is explanatory drawing explaining the outline of the wrinkle inspection apparatus which concerns on the same embodiment from upper direction. It is explanatory drawing explaining the outline of the wrinkle inspection apparatus which concerns on the same embodiment from a side surface. It is explanatory drawing explaining the outline of the optical fiber unit which concerns on the same embodiment. It is explanatory drawing explaining the outline of the optical fiber unit which concerns on the embodiment from upper direction. It is explanatory drawing explaining the outline of the image processing apparatus which concerns on the same embodiment. It is explanatory drawing explaining operation | movement of the wrinkle inspection apparatus which concerns on the same embodiment. It is a graph which shows the example of a measurement of the eyelid inspection device concerning the embodiment. It is a graph which shows the example of a measurement of the eyelid inspection device concerning the embodiment. It is explanatory drawing explaining the outline of the illuminating device which the eyelid inspection apparatus which concerns on 2nd Embodiment of this invention has. It is explanatory drawing explaining the outline of the illuminating device which the eyelid inspection apparatus which concerns on 3rd Embodiment of this invention has. It is a perspective view which shows schematic structure of the conventional wrinkle inspection apparatus. It is a perspective view which shows schematic structure of the conventional wrinkle inspection apparatus. It is a side view which shows schematic structure of the conventional wrinkle inspection apparatus. It is a graph which shows the example of the measurement result by the conventional wrinkle inspection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steel plate 2 Roll 100 Haze inspection apparatus 110 Illumination apparatus 110A Irradiation port 111 Light source 112 Optical fiber bundle 113 Optical fiber unit 114 1st optical fiber 115 2nd optical fiber 120 Imaging device 130 Image processing apparatus 140 Display apparatus 210 Normal line 220 1st Vertical line 230 Second vertical line 311 First direction 312, 315 First parallel light 313 Reflected light 321 Second direction 322, 325 Second parallel light 323 Reflected light 400 Irradiation area 510 Illuminating device 511 Light source 512 Prism sheet 512B First saw Prism 512C second sawtooth prism 610 illuminating device 611 first LED
612 Second LED
1301 Image acquisition unit 1303 Addition processing unit 1305 Average processing unit 1307 Differentiation processing unit 1309 Edge determination unit 1311 Storage unit 1313 Shading correction unit 1315 疵 candidate extraction unit 1317 疵 determination unit 1319 output unit

Claims (7)

A wrinkle inspection device that inspects wrinkles on the surface of the band-shaped body by irradiating a band-shaped light to an irradiation region crossing the moving band-shaped body in the width direction,
A first band light emitted in a first direction inclined by a predetermined first angle to one side in a width direction of the band with respect to the moving direction of the band, and the moving direction of the band Illuminating means for irradiating the irradiation region with second belt-like light emitted in a second direction inclined by a predetermined second angle on the other side in the width direction of the belt-like body;
An imaging means for imaging the reflected light of the first strip light and the second strip light in the irradiation region and outputting an image of the irradiation region;
Image processing means for specifying the positions of both edges in the width direction of the strip in the image of the irradiation area based on the intensity of the reflected light imaged by the imaging means;
A wrinkle inspection device comprising: The illumination means includes
A plurality of first optical fibers arranged in the width direction of the belt-like body and emitting light from a light source in the first direction;
A plurality of second optical fibers arranged in the width direction of the belt-like body and emitting light from the light source in the second direction;
The wrinkle inspection apparatus according to claim 1, comprising:   The illumination means includes a prism sheet that refracts the strip light from a light source in the first direction and the second direction to emit the first strip light and the second strip light. The wrinkle inspection apparatus according to claim 1. The illumination means includes
A first LED array arranged in the width direction of the strip and emitting the first strip light in the first direction;
A second LED array arranged in the width direction of the strip and emitting the second strip light in the second direction;
The wrinkle inspection apparatus according to claim 1, comprising: While moving the strip, the imaging means images the reflected light of the first strip light and the second strip light in the irradiation region a plurality of times,
The image processing means adds the intensities of the plurality of reflected lights that have been imaged, and identifies the positions of both edges in the width direction of the strip in the image of the irradiation region based on the intensities of the added reflected lights. The wrinkle inspection device according to any one of claims 1 to 4, wherein A wrinkle inspection method for inspecting wrinkles on the surface of the band-shaped body by irradiating a band-shaped light to an irradiation region crossing the moving band-shaped body in the width direction,
A first band light emitted in a first direction inclined by a predetermined first angle to one side in a width direction of the band with respect to the moving direction of the band, and the moving direction of the band Irradiating the irradiation area with a second band-shaped light emitted in a second direction inclined by a predetermined second angle on the other side in the width direction of the band-shaped body;
Imaging the reflected light of the first band light and the second band light in the irradiation area, and outputting an image of the irradiation area,
A wrinkle inspection method characterized by specifying the positions of both edges in the width direction of the belt-like body in the image of the irradiation region based on the intensity of the reflected light that has been picked up by predetermined image processing. While moving the band, the reflected light of the first band light and the second band light in the irradiation region is imaged a plurality of times,
Add up the intensities of the plurality of reflected lights that have been imaged,
The wrinkle inspection method according to claim 6, wherein the positions of both edges in the width direction of the belt-like body in the image of the irradiation region are specified based on the intensity of the added reflected light.

Images