JP2017067730A - Inspection system and inspection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection system, etc., with which it is possible to suitably inspect a laminate workpiece.SOLUTION: While a laminate workpiece 20 is conveyed, a red inspection light is radiated from a lighting device 7a at the side thereof in a direction approximately parallel to the laminate surface, and the inspection light reflected along a conveyance path is received and photographed by a photographing device 5. In addition, a blue inspection light is radiated from a lighting device 7b to the laminate surface, and the inspection light regular-reflected from the laminate surface is received by the photographing device 5. Furthermore, a green inspection light is radiated to the laminate surface by a lighting device 7c, and the inspection light diffusion-reflected from the laminate workpiece 20 is received by the photographing device 5. The laminate workpiece 20 is inspected using the red, blue, and green components of the image obtained by photographing the laminate workpiece 20 this way.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an inspection system for inspecting a laminated product.

  The laminating apparatus is an apparatus that superimposes a web-like base material and a resin film while carrying them, and adheres (laminates) the resin film on the base material. Examples of such a laminating apparatus are described in Patent Documents 1 and 2.

  The product after being laminated (laminated product) is inspected for defects such as wrinkles for quality control and the like. Conventionally, a laminating apparatus has been visually inspected by dedicated inspection personnel.

JP 2011-201316 JP 2014-46675 A

  However, with the inspection method by visual inspection, the production speed can only be increased to about 20 m / min, the production speed of the product is slow, and defects are overlooked.

  This invention is made | formed in view of said problem, and it aims at providing the test | inspection system etc. which can perform the test | inspection of a laminated product suitably.

  A first invention for solving the above-described problem is an inspection system for inspecting a laminated product obtained by laminating a base material, and laminating from a side in a conveying direction of the laminated product being conveyed. A first illumination that irradiates inspection light in a direction substantially parallel to the surface, and an imaging device that receives and inspects the inspection light from the first illumination reflected along the transport direction from the laminate surface, It is an inspection system characterized by having.

The inspection light of the first illumination is preferably red.
The inspection system of the first invention further includes a second illumination that irradiates the laminate surface with a blue inspection light, and the imaging device includes the second illumination that is regularly reflected from the laminate surface. It is desirable to further receive the inspection light.
Moreover, it has 3rd illumination which irradiates the green test | inspection light with respect to the said laminate surface, and the said imaging device further receives the test | inspection light from the said 3rd illumination diffusely reflected from the said laminate processed material. Is desirable.

  The second invention is an inspection method for inspecting a laminated product obtained by laminating on a substrate, and the first illumination illuminates the laminate surface from the side in the conveying direction of the laminated product being conveyed. An inspection method in which inspection light is irradiated in a substantially parallel direction, and an imaging device receives the inspection light from the first illumination reflected from the laminate surface along the transport direction and performs imaging. is there.

  In the present invention, during the conveyance of the laminate processed product, the inspection light in the direction substantially parallel to the laminate surface is irradiated from the side, and the inspection light reflected along the conveyance direction is received by the imaging device to perform imaging. Further, wrinkles and the like in the conveying direction that are most likely to occur during laminating appear bright on the image. Therefore, by applying a technique such as image processing to the image and automatically detecting defects such as wrinkles, the laminated product can be inspected more accurately than the conventional visual inspection, and the production speed is increased. be able to.

  Further, by using high-intensity red inspection light as the above-described inspection light, wrinkles and the like are likely to appear on the image, and a more accurate inspection can be performed. In addition, by simultaneously irradiating blue inspection light and green inspection light, it is possible to inspect a plurality of types of defects related to laminated products using the red component, blue component, and green component of a color image captured by a single imaging device. An inspection system that can be performed separately and can detect these multiple types of defects separately can be constructed in a small space.

  In the present invention, the blue inspection light is applied to the laminate surface, and the inspection light that is specularly reflected from the laminate surface is received by the above-described imaging device, so that when the laminate surface has scratches or the like, an image of the blue component is obtained. Appears as a dark area above. Therefore, defects such as scratches on the laminated product can be suitably detected based on this image. Blue inspection light with a short wavelength has the characteristic of being easily reflected on the surface, and reacts most sensitively to changes in the reflection characteristics of the laminate surface, so it exhibits performance in the inspection of scratches on the laminate surface.

  In addition, by illuminating the laminate surface with green inspection light and receiving the inspection light diffusely reflected from the laminated product with the above photographing device, the image of the substrate of the laminated product can be inspected from the image by the green component. it can. The wavelength of the green inspection light is relatively close to that of white light, and a highly accurate pattern inspection close to that when white light is used is possible. In addition, it is possible to align with the reference image based on the pattern and eliminate the influence of meandering of the laminated product, so that not only the defects of the pattern but also the positions of the defects such as wrinkles and scratches are accurate. It is possible to obtain a highly accurate inspection by correcting the position.

  INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an inspection system or the like that can suitably inspect a laminated product.

Diagram showing inspection system 1 The figure which shows arrangement | positioning of the imaging device 5 and illumination 7a-7c The figure which shows the laminated product 20 Examples of images 40a-40c The figure which shows the mode of the inspection light 71a The figure which shows the mode of the inspection light 71b Flow chart showing the inspection method Diagram showing inspection system 1a

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
(1. Inspection system 1)
FIG. 1 is a diagram showing an inspection system 1 according to the first embodiment of the present invention. An inspection system 1 shown in FIG. 1 is provided in a laminating apparatus (not shown) in a conveyance path for conveying a laminated product 20 after being laminated, and automatically in-line inspects the laminated product 20 being conveyed. Is to do.

  The inspection system 1 includes a control device 3, an imaging device 5, illuminations 7 a to 7 c, an alarm device 9, an operation device 11, and the like, and inspects a laminate workpiece 20 that is transported in the direction indicated by arrow A by the transport roller 30. Do.

  FIG. 1 shows the arrangement of the photographing device 5 and the illuminations 7a to 7c when viewed from the side in the conveying direction of the laminated product 20. 2A and 2B are views of the arrangement of the photographing device 5 and the illuminations 7a to 7c as viewed from above the laminated product 20 and from the rear in the transport direction (see arrow B in FIG. 1).

  As shown in FIG. 3, the laminated product 20 is obtained by forming a transparent laminate layer 23 on a web-like base material 21 by sticking a web-like resin film such as polypropylene. Hereinafter, the surface on which the laminate layer 23 is formed in the laminate product 20 is referred to as a laminate surface, and in the following description, the laminate surface is the top surface of the laminate product 20. The laminated product 20 is, for example, a bookbinding cover, and a pattern is formed on the base material 21 by printing or the like. However, the laminated product 20 is not limited to this.

  The control device 3 controls the photographing device 5 and the illuminations 7a to 7c to photograph the laminated product 20 being conveyed, and inspects the laminated product 20 from the photographed image. In the present embodiment, as an inspection of the laminated product 20, detection of wrinkles and scratches on the laminate surface, inspection of the pattern of the base material 21, and the like are performed. The control device 3 includes a PLC (programmable logic controller) that controls the photographing device 5 and the like, and a computer that performs image processing of a photographed image.

  The photographing device 5 photographs the laminate processed product 20 under the control of the control device 3 and is disposed above the laminate surface. The photographing device 5 is composed of, for example, a 3CCD color line camera and a three-plate camera lens, and receives light of three colors of RGB by three image sensors per pixel. The photographing range by the photographing device 5 is a line shape along the width direction of the laminated product 20, and this photographing range is indicated by C in FIGS. 1, 2A, and 2B. The width direction of the laminated product 20 is a direction orthogonal to the conveyance direction of the laminated product 20 (see arrow A in FIGS. 1 and 2A).

  The illuminations 7a to 7c irradiate the photographing range C on the laminate surface with inspection light, and respectively use red (R), blue (B), and green (G) monochromatic light as inspection light.

  The illumination 7a is disposed on the side of the laminate workpiece 20 in the conveying direction, and irradiates red monochromatic light in a direction substantially parallel to the laminate surface along the longitudinal direction of the photographing range C on the laminate surface. The imaging device 5 performs imaging by receiving inspection light reflected along the transport direction in plan view from the laminate surface. An LED (Light Emitting Diode) light source with high directivity is used as the illumination 7a. In this embodiment, as shown in FIG. 5A described later, the inspection light is irradiated in a direction slightly inclined (for example, about 1 to 2 °) with respect to the laminate surface.

  The illumination 7b is disposed above the laminate surface, that is, on the same side as the imaging device 5 with respect to the laminate surface, and emits blue inspection light along the transport direction in plan view. The illumination 7b is arranged so that the inspection light that has been specularly reflected in the imaging range C on the laminate surface is in a positional relationship where it is received by the imaging device 5. As the illumination 7b, line illumination using LED as a light source is used, and the long axis direction of the illumination 7b is arranged in accordance with the width direction of the laminate workpiece 20 as shown in FIG.

  The illumination 7c is also arranged on the same side as the imaging device 5 with respect to the laminate surface, and irradiates green inspection light from directly above the imaging range C toward the laminate surface. The imaging device 5 receives the inspection light diffusely reflected from the laminated product 20. As the illumination 7 c, diffusive line illumination using an LED as a light source is used, and the long axis direction of the illumination 7 c is arranged in accordance with the width direction of the laminated product 20 as in the illumination 7 b.

  Although not particularly illustrated, the photographing device 5, the illuminations 7a to 7c, and the like are disposed in a dark room, and the laminated product 20 is photographed in a state where external light is blocked.

  The alarm device 9 is a device that issues an alarm when a defect in the laminated product 20 is detected, and is a lamp such as a buzzer or Patlite (registered trademark), for example.

  The operation device 11 performs various operations related to the inspection system 1. It is also possible to provide a monitor as the operation device 11 to display a defect detection result and to perform various operations using the touch panel of the monitor.

(2. Image of laminated product 20)
The photographing device 5 is a line camera, and obtains a photographed image by continuously photographing the above-described line-shaped photographing range C of the laminate processed product 20 being conveyed.

  The captured image is corrected in size according to the line speed of the laminating apparatus, and the R value (red component), B value (blue component), and G value (green component) of each pixel of the captured image are extracted. Thus, three images 40a, 40b, and 40c illustrated in FIGS. 4A, 4B, and 4C are obtained. Hereinafter, these may be referred to as R image 40a, B image 40b, and G image 40c. In addition, the horizontal direction of each image 40a-40c of FIG. 4 (a)-(c) respond | corresponds to the conveyance direction of the laminate processed material 20. FIG.

  As shown in FIG. 4 (a), in the R image 40a, wrinkles 231 in the conveyance direction of the laminated product 20 appear brighter than other portions.

  This is because, as shown in FIG. 5 (a), the red inspection light 71a from the illumination 7a is directed in a different direction from the imaging device 5 on the normal laminated surface, but the laminated surface as shown in FIG. 5 (b). If there is a wrinkle 231, the inspection light 71 a hits the protruding portion of the wrinkle 231 and is diffusely reflected, and a part of it is reflected along the transport direction and received by the photographing device 5. 5A and 5B are views of the state of the inspection light 71a seen from the same direction as in FIG. 2B, and FIG. 5C shows the state of FIG. 5B in FIG. It is the figure seen from the same direction as (a). In FIGS. 5A to 5C, the illuminations 7b and 7c are not shown.

  The red inspection light 71a has a wavelength longer than that of blue and green and has a high light intensity, so that these differences are clearly apparent even with a small wattage. In general, the higher the height of the wrinkles 231 is, the higher the luminance on the image 40a is. In addition to the wrinkles 231, protrusions and deposits appear brightly on the R image 40a. As shown in FIG. 4 (a), if there is a bright portion in a streak shape, it can be identified as a wrinkle 231;

  On the other hand, as shown in FIG. 4B, in the B image 40b, the scratch 232 on the laminate surface appears darker than other portions.

  This is because, as shown in FIG. 6 (a), the blue inspection light 71b emitted from the illumination 7b is specularly reflected and directed to the photographing device 5 on the normal laminating surface, but as shown in FIG. 6 (b), the lamination is performed. This is because if there is a scratch 232 on the surface, the inspection light 71b is diffusely reflected by the depression, and the amount of light received by the photographing device 5 is reduced. 6A and 6B show the state of the inspection light 71b as seen from the same direction as in FIG. 1, and the illuminations 7a and 7c are not shown. Moreover, about the site | part which cannot adhere a laminate with the powder adhering to a paper (base material 21), it becomes a reflection of a film itself, and it can catch a lamination adhesion defect by becoming brighter.

  The blue inspection light 71b has a shorter wavelength than red and green and has a characteristic of being easily reflected on the surface. Therefore, since it is the most sensitive to the change in the reflection characteristics of the laminate surface, specular reflection light from the laminate surface is received by the photographing device 5, and the luminance due to the gloss of the surface is extracted from the B image 40b. There is a possibility that this luminance is affected by the pattern of the base material 21. With respect to this, the influence of the pattern can be excluded by performing correction by a pattern obtained from the G image 40c described later.

  As shown in FIG. 4C, in the G image 40c, a pattern 211 of the base material 21 of the laminated product 20 appears. The wavelength of the green inspection light is relatively close to that of white light, so that it is possible to obtain data close to the case where the image is taken under white light, and a general pattern inspection can be performed.

(2. Inspection method of laminated product 20)
Next, an inspection method for the laminated product 20 will be described with reference to FIG. FIG. 7 is a flowchart showing the inspection method, and each step is executed by the control device 3.

  In the present embodiment, as described above, the imaging device 5 controls the laminated product 20 under the control of the control device 3 in a state in which the laminating surface of the laminated product 20 being conveyed is irradiated with inspection light by the lights 7a to 7c. Shooting is performed (S1). The captured image is transmitted from the imaging device 5 to the control device 3, and the control device 3 receives and acquires the captured image.

  In the present embodiment, the control device 3 acquires the G image 40c from the captured image, compares the G image 40c with the reference image, aligns the pattern 211 (S2), and performs the G image 40c after alignment. The defect of the pattern 211 is detected by comparison with the reference image (S3). The defect of the pattern 211 is, for example, printing stain or missing printing, but is not limited thereto. The reference image is a G image obtained in advance for the laminate processed product 20 having no defect in the pattern 211 and is stored in the storage unit of the computer of the control device 3 or the like.

  In S2, for example, the image is corrected so that it matches the reference image by performing image position correction, expansion / contraction, etc., in units of finely divided images, and the influence of the position shift due to the behavior of the laminated product 20 such as meandering and vertical shift. Can be excluded. By using the information about the image correction, it is possible to obtain a correct position excluding the influence of the meandering of the laminate processed product 20 on the defects detected based on the images 40b and 40c in S4 and S5 described later.

  Further, the control device 3 detects a defect from the R image 40a (S4). As described above, since the wrinkles 231 and the like of the laminated product 20 appear brightly in the R image 40a, defects such as the wrinkles 231 can be detected using a known image processing method such as binarization. As described above, it can be determined whether the defect is a streak-like wrinkle 231 or other defects.

  Further, the control device 3 detects a defect from the B image 40b (S5). As described above, in the B image 40b, the scratch 232 portion of the laminated product 20 appears dark, so that the scratch 232 can be detected as a defect using a known image processing method such as binarization as described above. In addition, since the laminate adhesion failure portion as described above appears brighter, it is also possible to detect a laminate adhesion failure as a defect using a known image processing method such as binarization. As described above, when the influence of the picture 211 of the base material 21 appears in the B image 40b, the correction based on the picture 211 obtained from the G image 40c can be performed, and the influence of the picture 211 can be excluded.

  When a defect is not detected from any image (S6; NO), the control device 3 ends the process as it is, but when a defect is detected from any image (S6; YES), the alarm device 9 Is controlled to generate an alarm (S7).

  In S7, for example, depending on the inspection results of the images 40a to 40c, the type of alarm can be changed according to the type of defect such as wrinkles 231, scratches 232, and defects of the picture 211, or the paper can be automatically discharged according to the type of defect. . Similarly, depending on the defect type, it is possible to perform processing such as recording that a defect has been detected without warning.

  As described above, according to the present embodiment, the inspection light 71a is irradiated from the side of the laminated workpiece 20 in the direction substantially parallel to the laminate surface and reflected along the conveyance direction during the conveyance of the laminate processed product 20. When the photographing device 5 receives the light 71a and performs photographing, a portion such as a wrinkle 231 in the conveyance direction that is most likely to occur during laminating appears brightly on the image 40a. Accordingly, by applying a technique such as image processing to the image 40a and automatically detecting defects such as the wrinkles 231 or the like, the laminated product 20 can be inspected more accurately than the conventional visual inspection, and the laminating process can be performed. The production speed of the product 20 can be increased.

  Further, by using the high-intensity red inspection light 71a as the inspection light, wrinkles 231 and the like are likely to appear on the image 40a, and a more accurate inspection can be performed. Further, by simultaneously irradiating the blue inspection light 71b and the green inspection light, a plurality of types of defects relating to the laminate processed product 20 are caused by the red component, the blue component, and the green component of the color image photographed by one photographing apparatus 5. The inspection system 1 that can separately detect these plural types of defects can be constructed in a small space.

  In the present embodiment, the blue inspection light 71b is irradiated on the laminate surface, and the inspection light 71b specularly reflected from the laminate surface is received by the photographing device 5, so that if there is a scratch 232 or the like on the laminate surface, the image 40b Appears as a dark part, and a poorly bonded part of the laminate appears bright. Therefore, similarly to the above, it is possible to suitably detect defects such as scratches 232 and poor lamination adhesion based on the image 40b. The blue inspection light 71b having a short wavelength has a characteristic of being easily reflected on the surface, and reacts most sensitively to a change in the reflection characteristic of the laminate surface, and therefore exhibits performance in the inspection of the film surface condition such as a flaw 232 on the laminate surface.

  Further, the inspection surface 211 of the base material 21 of the laminated product 20 is inspected from the image 40c by irradiating the green inspection light onto the laminate surface and receiving the inspection light diffusely reflected from the laminated product 20 by the photographing device 5. Can do. The wavelength of the green inspection light is relatively close to that of white light, and a highly accurate pattern inspection close to that when white light is used is possible. In addition, since it is possible to perform alignment with the reference image based on the pattern 211 and eliminate the influence of the meandering of the laminated product 20, not only the defect of the pattern 211 but also the wrinkles 231, scratches 232, and the like described above. The position of the defect can also be obtained accurately, and a highly accurate inspection can be performed by correcting the position.

  However, the present invention is not limited to this. Hereinafter, another example of the present invention will be described as a second embodiment. The second embodiment will be described with respect to differences from the first embodiment, and the same points will be denoted by the same reference numerals in the drawings and the like, and the description thereof will be omitted.

[Second Embodiment]
FIG. 8 is a view showing an inspection system 1a according to the second embodiment in the same manner as FIG. As shown in the figure, this embodiment is different from the first embodiment in that the illuminations 7b and 7c are omitted. The illumination 7a ′ has the same arrangement as that of the illumination 7a, but white inspection light is used instead of red monochromatic light.

  Even in this inspection system 1a, it is possible to inspect the wrinkles 231 and the like of the laminated product 20 as in the first embodiment. In addition, the inspection of the scratch 232 and the like of the laminated product 20 described above can be performed using white light as inspection light with the same illumination arrangement as the illumination 7b. Similarly, the inspection of the pattern 211 of the laminated product 20 can also be performed using white light as inspection light with the same illumination arrangement as the illumination 7c.

  However, in this case, if three illuminations and the photographing device 5 are arranged as in the first embodiment, it is difficult to separate, for example, the pattern 211 and the scratch 232 in the image. For this reason, it is necessary to perform shooting at three locations by arranging each illumination and a set of imaging devices corresponding to each illumination at different positions, which requires a large space as an inspection system and is expensive.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

DESCRIPTION OF SYMBOLS 1, 1a; Inspection system 3; Control apparatus 5; Imaging | photography apparatus 7a, 7a ', 7b, 7c; Illumination 9; Alarm apparatus 11; Operation apparatus 20; Laminated product 21; 40b, 40c; Image 71a, 71b; Inspection light 211; Pattern 231; Wrinkle 232;

Claims (5)

An inspection system for inspecting a laminated product obtained by laminating a base material,
A first illumination for irradiating inspection light in a direction substantially parallel to the laminate surface from the side of the conveyance direction of the laminate workpiece being conveyed;
An imaging device that performs imaging by receiving inspection light from the first illumination reflected from the laminate surface along the conveyance direction;
An inspection system comprising:   The inspection system according to claim 1, wherein the inspection light of the first illumination is red. A second illumination for irradiating the laminate surface with blue inspection light;
The inspection system according to claim 2, wherein the imaging apparatus further receives inspection light from the second illumination that is regularly reflected from the laminate surface. A third illumination for irradiating the laminate surface with green inspection light;
The inspection system according to claim 3, wherein the imaging apparatus further receives inspection light from the third illumination diffusely reflected from the laminated product. An inspection method for inspecting a laminate processed by laminating on a base material,
With the first illumination, irradiate the inspection light in the direction substantially parallel to the laminate surface from the side in the transport direction of the laminate processed product being transported,
An inspection method, wherein the imaging device receives the inspection light from the first illumination reflected along the transport direction from the laminate surface and performs imaging.

Images