JPWO2018158824A1 - Container inspection apparatus and container inspection method - Google Patents

Abstract

The inspection device 1 includes a light emitting unit 20 having a light emitting surface 22, an imaging unit 40 disposed opposite to the light emitting unit 20 with the container 10 interposed therebetween, a determining unit 52 for determining whether there is a defect, and a light emitting unit 20. A first light restricting section 24 disposed on the container 10 side. The first light restricting unit 24 includes a light transmitting unit 244 and a light reducing unit 242 extending in the horizontal direction X along the light emitting surface 22. The first light restricting section 24 arranges the light transmitting sections 244 and the dimming sections 242 alternately in the vertical direction Y.

Description

  The present invention relates to a container inspection device and a container inspection method.

  As a method of detecting a thin bubble that is extremely rarely generated on the inner surface of a container, particularly a glass bottle, there is an inspection method proposed by the present applicant earlier (Patent Document 1).

  Thin bubbles are generated on the inner surface of the glass bottle and are formed by a very shallow depression with respect to the inner surface and a thin glass film covering the depression. In this inspection method, in order to detect thin bubbles, light is transmitted only through the slits and passes through the thin bubbles by using a striped filter in which a plurality of horizontally long slits are provided on the opaque plate at a certain interval vertically. The image is taken as an image in which the width of light and dark is compressed vertically by the light.

  Even with such a method, it is possible to detect thin bubbles, but it is possible to detect shadows due to thin bubbles, joints between light and dark due to uneven thickness of glass bottles, and joints between glass bottles (mold joints at molds). It is difficult to determine the difference between light and dark due to the difference in level). For this reason, even non-defective glass bottles are often determined to be defective, and a reduction in the non-defective product rate is desired.

  In addition, the present applicant has proposed an inspection apparatus that detects defects such as wrinkles of a glass bottle using a light control film (Patent Document 2). With this inspection device, it was difficult to detect a thin bubble in an extremely shallow depression on the inner surface.

Japanese Patent Publication No. 7-11490 JP 2013-134185 A

  An object of the present invention is to provide a container inspection apparatus and an inspection method capable of inspecting for the presence or absence of a defect such as a thin bubble having an unclear outline.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following aspects or application examples.

[Application Example 1]
The container inspection device according to this application example is:
A light emitting unit having a light emitting surface for irradiating the container with light,
An imaging unit arranged opposite to the light emitting unit with a container interposed therebetween,
A determining unit that determines the presence or absence of a defect based on the image of the container captured by the imaging unit;
A light restricting unit disposed on the container side of the light emitting unit,
Including
The light restricting unit includes a light transmitting unit and a light reducing unit extending in a horizontal direction along the light emitting surface,
The light transmitting portion and the light reducing portion are alternately arranged in the vertical direction,
The light transmitting unit transmits light emitted from the light emitting unit to the container side,
The light reducing unit includes a plurality of blinds extending in the horizontal direction in the vertical direction, and limits an incident angle of the light emitted from the light emitting unit with respect to the vertical direction.

  According to this application example, it is possible to inspect the presence or absence of a defect such as a thin bubble whose contour is unclear due to a change in luminance in the vertical direction of the container surface due to the light transmitting portion and the light reducing portion.

[Application Example 2]
In the container inspection device according to this application example,
The light reducing unit may be disposed on a light emitting surface of the light emitting unit, and may have a height from the light emitting surface of 0 mm to 100 mm.

  According to this application example, it is possible to suppress the shadow of the seam in the captured image and enhance the shadow of a defect such as a thin bubble having an unclear outline.

[Application Example 3]
In the container inspection device according to this application example,
The width of the light transmitting portion in the vertical direction may be 3 mm to 6 mm.

  According to this application example, it is possible to recognize a shadow of a defect contour such as a thin bubble having an unclear contour.

[Application Example 4]
In the container inspection device according to this application example,
The dimming part can be formed by stacking a plurality of light control films.

  According to this application example, by enhancing the intensity of light in the vertical direction on the surface of the container, the contour of a defect such as a thin bubble having an unclear contour can be enhanced.

[Application Example 5]
In the container inspection device according to this application example,
The light restricting unit is a first light restricting unit disposed at a position corresponding to a region below the predetermined height position of the container in the vertical direction,
On the container side of the light emitting unit, at a position corresponding to an area above the predetermined height position, further includes a second light restricting unit that reduces a transmission amount of light emitted from the light emitting unit,
The second light restricting unit may be disposed at a predetermined interval in the horizontal direction.

  According to this application example, the lower region of the container where defects such as thin bubbles having an unclear contour are likely to occur and the upper region where such defects are unlikely to occur are inspected by different optical systems. In addition, it is possible to eliminate the influence of unevenness in thickness and seams, to easily outline a defect such as a thin bubble, and to suppress the load of image processing.

[Application Example 6]
In the container inspection device according to this application example,
The determination unit recognizes at least one detection object from the captured image, and sets the vertical inspection region extending in the vertical direction and the horizontal inspection region extending in the horizontal direction in a predetermined range including the recognized detection object. However, when two or more detection objects are included in the vertical inspection area and the horizontal inspection area, it can be determined as a defect.

  According to this application example, a detection object whose outline is divided into a plurality of parts and recognized can also be determined as a defect.

[Application Example 7]
In the container inspection device according to this application example,
The determination unit recognizes at least one detection object from the captured image, and determines a defect based on an area related to the detection object when the shape of the recognized detection object is a ring-shaped detection object or an arc-shaped detection object. Can be determined.

  According to this application example, a detection object having an annular contour or a detection object having an arc-shaped contour can also be determined as a defect.

[Application Example 8]
In the container inspection device according to this application example,
The determination unit recognizes at least one detected object from the captured image, and determines a defect when a predetermined range including the recognized detected object includes a portion having a brightness equal to or higher than a predetermined threshold. can do.

  According to this application example, it is possible to determine even a detection object including a place where the contour is bright and a place where the contour is dark as a defect.

[Application Example 9]
The container inspection method according to this application example is as follows.
The light emitted from the light emitting unit and the light passing through the dimming unit that limits the incident angle of the light from the light emitting unit with respect to the vertical direction by the blind extending in the horizontal direction, and alternately in the container in the vertical direction. And irradiate
An image of the container is captured by an imaging unit arranged opposite to the light emitting unit with the container interposed therebetween,
It is characterized in that bubbles on the inner surface of the container are determined as defects.

  According to this application example, it is possible to inspect the presence or absence of a defect such as a thin bubble whose contour is unclear due to a change in luminance in the vertical direction of the container surface due to the light transmitting portion and the light reducing portion.

  The present invention can provide a container inspection apparatus and an inspection method capable of inspecting for the presence or absence of a defect such as a thin bubble having an unclear outline.

FIG. 1 is a side view of the container inspection device. FIG. 2 is a front view of the light emitting unit, the first light limiting unit, and the second light limiting unit. FIG. 3 is a diagram showing the containers and their images side by side. FIG. 4 is an enlarged sectional view of a thin bubble. FIG. 5 is an enlarged view of A in FIG. FIG. 6 is a diagram for explaining the form of the outline of a thin bubble in a captured image. FIG. 7 is a diagram illustrating an inspection mode in the determination unit. FIG. 8 is a flowchart of the container inspection method.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, all of the configurations described below are not necessarily essential components of the invention.

  The container inspection apparatus according to the present embodiment has a light-emitting unit having a light-emitting surface that irradiates light to the container, an imaging unit disposed opposite to the light-emitting unit with the container interposed therebetween, and an image captured by the imaging unit. A determining unit that determines the presence or absence of a defect based on an image of the container; and a light limiting unit disposed on the container side of the light emitting unit, wherein the light limiting unit extends in a horizontal direction along the light emitting surface. Including a light transmitting part and a light reducing part, the light transmitting part and the light reducing part are alternately arranged in a vertical direction, and the light transmitting part transmits light emitted from the light emitting part to a container side. The light reduction unit includes a plurality of blinds extending in the horizontal direction in the vertical direction, and limits an incident angle of light with respect to the vertical direction, of light emitted from the light emitting unit. .

1. Outline of Container Inspection Apparatus An outline of the container inspection apparatus 1 will be described with reference to FIGS. FIG. 1 is a side view of the inspection device 1 (hereinafter, referred to as “inspection device 1”) of the container 10, and FIG. 2 is a front view of the light emitting unit 20, the first light limiting unit 24, and the second light limiting unit 26. FIG. 3 is a diagram showing the containers and their images side by side.

  As shown in FIGS. 1 to 3, the inspection apparatus 1 includes a light emitting unit 20 having a light emitting surface 22 for irradiating the container 10 with light, and an imaging unit arranged to face the light emitting unit 20 with the container 10 interposed therebetween. 40, a determination unit 52 that determines the presence or absence of a defect based on the image 80 (FIG. 3) of the container 10 captured by the imaging unit 40, and a first light restricting unit 24 arranged on the container 10 side of the light emitting unit 20. ,including.

  The first light restricting unit 24 is arranged at a position corresponding to the area 13a below a predetermined height position H1 (FIG. 3) in the vertical direction Y of the container 10. The inspection device 1 can further include a second light restricting unit 26. The second light restricting unit 26 is disposed on the container 10 side of the light emitting unit 20 and at a position corresponding to the region 13b above the predetermined height position H1. The lower region 13a of the container where defects such as thin bubbles with unclear contours are likely to occur and the upper region 13b where such defects are unlikely to occur are formed by different optical systems (the first light restricting portion 24 and the second Inspection by the light restricting unit 26) eliminates the influence of unevenness in the thickness and seams, makes it easier to outline a defect such as a thin bubble, and suppresses the load of image processing. Therefore, if the load on the control unit 50 does not matter, the first light restricting unit 24 may be arranged so as to correspond to the entire container 10. In addition, a defect is mentioned later.

  Here, as shown in FIG. 1, the container 10 is inspected in an upright state, that is, in a state where the axis 12 is along the vertical direction Y. The vertical direction Y is a direction of gravity, and the horizontal direction X is a direction orthogonal to the vertical direction Y.

  The inspection device 1 includes a rotation support unit 30 that supports the container 10 while rotating the container 10 around the axis 12, and a side roller 32 that rotates the container 10 while contacting the side surface of the container 10. Although the side roller 32 is illustrated as being between the container 10 and the imaging unit 40 in FIG. 1, the side roller 32 is for convenience of description of the side roller 32, and the side roller 32 is It is placed in a position that does not interfere with shooting.

  The container 10 is a glass bottle and is transparent or translucent. The translucency is such a degree of transparency that a defect on the inner surface 15 of the container 10 can be determined by light from the light emitting unit 20 transmitted through the container 10. The container 10 is, for example, circular in cross section. The cross-sectional shape of the container 10 may be polygonal.

  The predetermined height position H1 differs depending on the type of the container 10, the state of molding, and the like. The predetermined height position H1 may be a so-called settle line. The settle line is a part where the wall thickness changes at the boundary between the part that is in contact with the mold and the part that is not in contact with the mold due to the settle blow for forming the mouth. The settle line is formed in the horizontal direction X of the container 10. The predetermined height position H1 can be set at the boundary between the lower region 13a of the container 10 where the thin bubbles 18 are easily generated and the upper region 13b of the container 10 where the thin bubbles 18 are unlikely to be generated.

  The inspection device 1 uses the light transmitted through the container 10 to image the body 13 of the container 10 with the imaging unit 40, and detects a portion darker than the surroundings in the captured image 80 (FIG. 3) as a detection object in the container 10. This is a light transmission type inspection apparatus 1.

2. 3. Defects A defect to be detected by the inspection apparatus 1 will be described with reference to FIGS. FIG. 4 is an enlarged sectional view of the thin bubble 18. In FIG. 4, the light transmission amount is represented by the thickness of the arrow.

  As shown in FIG. 3, when the body 13 of the container 10 is imaged by the imaging unit 40, an image 80 is obtained. In the image 80, for example, the seam 16, the thin bubble 18, and the meat unevenness 19 can be confirmed as detection objects. The seam 16 is not a defect, and the step of the seam of the mold for molding the container 10 appears in the image 80 as a dark line along the vertical direction Y. The thin bubble 18 is a defect that rarely occurs at a position below the predetermined height position H1 of the container 10. The thickness unevenness 19 is not a defect but a dark portion that is caused by a change in the thickness of the body 13 of the container 10. There are also other drawbacks such as burns.

  The thin bubbles 18 may be generated below the predetermined height position H1 of the container 10 and on the inner surface 15 of the container 10. The thin foam 18 is generated due to a difference in ease of elongation due to a temperature difference of the parison in the molding process of the container 10. The thin bubble 18 is a hollow bubble having a very shallow concave portion (for example, a depth of 100 μm or less from the inner surface 15) and has a substantially circular contour. Therefore, in the image 80, the outline of the thin bubble 18 appears slightly darker than the surroundings. However, since the brightness is almost the same as that of the joint 16 and the unevenness 19 of the thickness, it is difficult to distinguish the outline. The inspection device 1 must be able to discriminate between the thin bubbles 18 and the non-defective parts such as the seams 16 and uneven meat 19.

  However, if only the filter as in the conventional patent document 1 is used, the seam 16 is determined as a defect when the thin bubble 18 is to be detected, and the container 10 which is originally a good product may be excluded as a defective product. The same applies to the method of Patent Document 2. This is because the change in brightness between the thin bubble 18 and the surroundings is small, and there is not much difference in brightness between the thin bubble 18 and the seam 16 which is not a defect.

3. Light-Emitting Unit The light-emitting unit 20 will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the light emitting unit 20 is a light source that illuminates the container 10. The light emitting unit 20 is a surface light source that has a light emitting surface 22 on the container 10 side and can illuminate the container 10 from the opposite side of the imaging unit 40. The light emitting unit 20 is set to have a size capable of illuminating the entirety of the largest container 10 to be inspected by the inspection device 1.

  As shown in FIG. 2, the light emitting section 20 has a rectangular light emitting surface 22 on the container 10 side, and substantially the entire surface emits light. The light emitting unit 20 is disposed so as to face the container 10 and the imaging unit 40, and light transmitted through the container 10 reaches the imaging unit 40.

  As the light source of the light emitting section 20, a known light source such as an LED or an organic EL can be used. The light emitting unit 20 is diffuse illumination, and when LEDs are used, uniform light can be applied to the container 10 using a diffusion plate on the front surface (light emitting surface 22) of the light source. As the diffusion plate, a known diffusion plate that diffuses light from a light source such as an LED and emits the light to the outside can be used. By diffusing the light by the diffusion plate, it is possible to reduce unevenness in a portion where no light source exists when a large number of light sources are used.

  On the light emitting surface 22, a light limiting section is provided.

4. Light Limiting Unit The first light limiting unit 24 and the second light limiting unit 26, which are light limiting units, will be described with reference to FIGS. In FIG. 2, the container 10 indicated by a broken line is for explaining the positional relationship between the first light restricting unit 24 and the second light restricting unit 26. FIG. 5 is an enlarged view of A in FIG.

4-1. First Light Limiting Unit As shown in FIGS. 1, 2 and 5, the first light limiting unit 24 is located at a position corresponding to an area 13a below a vertical predetermined height position H1 (FIG. 3) of the container 10. Placed in This is for surely detecting the thin bubbles 18 that tend to be generated below the container 10. The first light restricting unit 24 includes a light transmitting unit 244 and a light reducing unit 242 that extend in the horizontal direction X along the light emitting surface 22. The first light restricting unit 24 arranges the light transmitting units 244 and the light reducing units 242 alternately in the vertical direction Y. This is because the first light restricting unit 24 transmits the light diffused and emitted in the horizontal direction X from the light emitting surface 22 toward the container 10 and restricts the light diffused and emitted in the vertical direction Y.

  The light transmitting unit 244 transmits light emitted from the light emitting unit 20. The light transmission part 244 is a slit. The light transmitting portion 244 has nothing to block the light from the light emitting surface 22. In order to eliminate the shadow of the joint 16, the container 10 can be illuminated with sufficient horizontal light transmitted through the light transmitting portion 244.

  As shown in FIG. 5, the dimming unit 242 includes a plurality of blinds 243 extending in the horizontal direction X in the vertical direction Y, and adjusts the incident angle of the light with respect to the vertical direction Y in the light emitted from the light emitting unit 20. Restrict. The blind 243 is formed so as to extend in the horizontal direction X and the thickness direction of the dimming unit 242. Of the diffused light on the light emitting surface 22, light along the blinds 243 is preferentially transmitted through the dimming unit 242. Therefore, the diffused light on the light emitting surface 22 is narrowed down by the light reducing portion 242, and in particular, transmission of light diffused in the vertical direction Y is restricted. The blind 243 extends, for example, in a direction orthogonal to the light emitting surface 22. Therefore, the dimming unit 242 transmits the light in the horizontal direction X emitted from the light emitting surface 22 preferentially.

  As described above, the change in the luminance in the vertical direction Y of the inner surface 15 of the container 10 due to the light transmitting part 244 and the light reducing part 242 is a stripe pattern having a gradual change in luminance as shown in the image 80 in FIG. appear. Then, due to the change in the luminance in the vertical direction Y, a defect such as the thin bubble 18 having an unclear outline can be confirmed in the image 80, and the presence or absence of the defect can be determined in the inspection device 1.

  In addition, since light diffused in the horizontal direction X reaches the container 10 sufficiently by the light transmitting portions 244 and the light reducing portions 242 alternately arranged in the vertical direction Y, the dark seam 16 caused by the level difference in the horizontal direction appears on the image 80. Is less likely to appear (the change in luminance is smaller). If the unevenness 19 also appears as a change in the thickness in the horizontal direction, it is less likely to appear as a dark portion in the image 80 (the change in luminance is reduced).

  The dimming unit 242 is disposed on the light emitting surface 22 of the light emitting unit 20 and has a height from the light emitting surface 22 of 0 mm to 100 mm. Since the dimming unit 242 has a predetermined thickness, it is possible to suppress the shadow of the seam 16 and enhance the shadow of a defect such as the thin bubble 18 whose outline is unclear in the captured image 80. it can. The height of the light reducing portion 242 from the light emitting surface 22 may be further 0 to 100 mm.

  The dimming unit 242 is formed by stacking a plurality of light control films. By emphasizing the intensity of light in the vertical direction Y of the inner surface 15 of the container 10, the outline of a defect such as a thin bubble 18 whose outline is unclear can be emphasized. FIG. 5 shows an example in which two light control films each having a thickness of 0.5 mm are overlapped in the thickness direction and bonded. A commercially available light control film can be used. For example, “LIGHT CON FILM 60DEG 12 × 11” manufactured by 3M can be adopted.

  The width of the light transmitting portion 244 in the vertical direction Y may be 3 mm to 6 mm. When the inventors examined a variety of samples of thin bubbles 18, the width was appropriate for recognizing shadows of defective contours such as thin bubbles 18 with unclear contours.

  In a later-described image processing unit 53, a portion corresponding to the lower region 13 a in the image 80 is subjected to a difference process in the horizontal direction X and a difference process in the vertical direction Y, so that a stripe pattern formed by the dimming unit 242 and the light transmitting unit 244. The dark portion of the seam 16 and the unevenness 19 can be removed, and the shadow of the outline of the thin bubble 18 can be left.

  As shown in FIG. 2, the first light restricting section 24 is provided with a plurality of (three in FIG. 2) slits at predetermined intervals on a thin sheet in which two light control films are bonded together. 242 and light transmitting portions 244 are provided alternately. The first light restricting portion 24 has elongated holes 246 extending in the vertical direction Y at both ends in the width direction (horizontal direction X), and is fixed to the light emitting portion 20 by bolts 28. The first light restricting unit 24 is movable in the vertical direction Y along the long hole 246, and can be adjusted in position according to the height of the container 10.

4-2. Second Light Limiting Unit As shown in FIG. 2, two second light limiting units 26 are arranged at predetermined intervals at positions corresponding to the area 13b above the predetermined height position H1. This is because a very shallow thin bubble 18 such as the lower region 13a is not generated. As long as the second light restricting section 26 has a predetermined interval through which light from the light emitting section 20 can be transmitted, the two may be connected or may be formed integrally.

  The two second light restricting units 26 reduce the transmission amount of light emitted from the light emitting unit 20. The two second light restricting units 26 are arranged at predetermined intervals in the horizontal direction X. Since the bubbles on the inner surface 15 generated in the upper region 13b are not extremely shallow thin bubbles 18, they can be detected even by the structure of the second light restricting unit 26. The predetermined interval in the horizontal direction X is smaller than the width in the horizontal direction X of the region 13b above the body portion 13. In an image processing unit 53 to be described later, a portion corresponding to the upper region 13b in the image 80 is subjected to difference processing in the vertical direction Y, so that a dark portion of the seam 16 and the flesh unevenness 19 can be removed.

  As the second light restricting unit 26, a light shielding plate can be used. As the light shielding plate, a thin metal plate, for example, an iron plate can be used.

  The second light restricting unit 26 is fixed to the light emitting unit 20 with a bolt 28 at an end of the light emitting unit 20 in the horizontal direction X. The second light restricting portion 26 has two long holes 264 at the top and bottom, and can be moved in the vertical direction Y by loosening the bolt 28, and the position can be adjusted according to the height of the container 10.

5. Rotation Support Section As shown in FIG. 1, the rotation support section 30 and the side rollers 32 rotate the container 10 around the axis 12. The rotation support 30 supports the bottom 14 of the container 10. The axis 12 is an imaginary line serving as a rotation center axis around which the container 10 rotates.

  The rotation support section 30 may be a member for transporting the container 10 to a predetermined position to be inspected shown in FIGS. 1 and 2 while supporting the container 10. In this case, the container 10 is sequentially and intermittently conveyed to a predetermined position where the container 10 is inspected by the rotation support unit 30, and the container 10 is rotated about the axis 12 when the container 10 is disposed at the predetermined position.

  The rotation support unit 30 transmits the driving force of the motor 60 to the rotation support unit 30 and the side rollers 32 via the belt 35 and the like according to a command from the rotation control unit 62, and rotates. When the container 10 is transported to the position to be inspected, the rotation support unit 30 performs a predetermined amount of rotation at a predetermined speed. The predetermined amount of rotation is an amount sufficient to image the entire circumference of the container 10. The predetermined amount of rotation is set to 1.2 rotations or more so that one image data can grasp the entire detection object. The amount of rotation of the rotation support unit 30 is calculated by the control unit 50 based on the output of the rotation detection unit 54. The rotation detection unit 54 can be a rotary encoder attached directly or indirectly to the motor 60.

6. Imaging Unit As shown in FIG. 1, the imaging unit 40 is arranged to face the light emitting unit 20 with the container 10 interposed therebetween. The imaging unit 40 is arranged to photograph the surface of the container 10 on the axis 12. The imaging unit 40 can photograph at least a part to be inspected of the container 10, and is arranged here so that the entire body 13 in the vertical direction Y of the container 10 is within the field of view of the imaging unit 40.

  The imaging unit 40 can capture an image including the detection object (including the thin bubble 18) by the light of the light emitting unit 20 transmitted through the container 10. As the imaging unit 40, for example, a known line sensor camera can be used. The imaging unit 40 captures an image in accordance with the rotation speed of the rotation support unit 30 based on the output of the rotation detection unit 54, so that even if the rotation speed changes for some reason, the image 80 is not affected.

  The imaging unit 40 photographs the entire circumference of the body 13, sends the data to the image processing unit 53 of the control unit 50, and performs predetermined processing on the image 80. As shown in FIG. 3, in the image 80 before the image processing, a stripe pattern extending in the horizontal direction X appears at a portion corresponding to the area 13 a below the trunk 13. This is the effect of the dimming unit 242 and the light transmitting unit 244 of the first light restricting unit 24 shown in FIGS.

  The portion corresponding to the lower region 13 a in the image 80 irradiates the body 13 with a large amount of light diffused in the horizontal direction X by the first light restricting unit 24, and the light diffused in the vertical direction Y is below the body 13. , The shadow of the joint 16 hardly appears in the image 80. The seam 16 and the uneven spot 19 in the upper region 13b corresponding to the second light restricting portion 26 not having the structure like the first light restricting portion 24 appear in the image 80.

  The image processing unit 53 performs a known gradation conversion process on the image 80 in the vertical direction Y so as to eliminate the stripe pattern by the first light restricting unit 24, and performs the joint 16 of the upper region 13 b and the unevenness 19 of the flesh 19. A known gradation conversion process in the horizontal direction X can be performed so as to eliminate the shadow. As the gradation conversion processing, for example, a shading correction processing, a processing of performing gradation conversion based on a difference from a reference image, a dynamic threshold value method (dynamic binarization processing), and the like can be adopted. As the gradation conversion processing, for example, real-time shading correction by Keyence Corporation can be adopted. The real-time shading correction refers to correcting a change in the background brightness of image data that may occur due to the illumination state of the container 10 to be inspected. For example, when brightness unevenness such that a portion corresponding to the bottom portion 14 in the image 80 is darker than the body portion 13 occurs, correction is performed by real-time shading correction so that the overall brightness becomes uniform on average.

  Therefore, the presence / absence of the thin bubble 18 can be detected more accurately while accurately distinguishing the thin bubble 18 from the seam 16 and the meat unevenness 19.

7. Determination Unit As shown in FIG. 1, the determination unit 52 is a part of the control unit 50. Therefore, the control unit 50 instructs the subsequent processing of the inspected container 10 based on the determination result of the determination unit 52. The determination unit 52 may be provided separately from the control unit 50. In that case, the determination result of the determination unit 52 is notified to the control unit 50.

  The determination unit 52 will be described in more detail with reference to FIGS. FIG. 6 is a diagram for explaining aspects of the outlines 18a to 18d of the thin bubbles 18 in a captured image, and FIG. 7 is a diagram for explaining an inspection mode in the determination unit 52. 6 and 7 show outlines 18a to 18d of the thin bubbles 18 after the image 80 of FIG. 3 is subjected to the difference processing in the vertical direction Y and the horizontal direction X by the image processing unit 53.

  As a result of inspecting many containers 10, it was confirmed that there were four types of contours 18a to 18d. FIG. 6 schematically shows an annular contour 18a, a divided contour 18b, an arc-shaped contour 18c, and a bright portion 18d. The determination unit 52 has an inspection method for recognizing the four types of contours 18a to 18d as defects (thin bubbles 18).

  Based on the image data after the image processing, the determination unit 52 recognizes a portion darker than the surroundings as a detection object by, for example, shading of brightness, and performs all the following determination processing for each of the detection objects. Then, the container 10 determined to have a defect by the determination unit 52 is determined to be defective, and the control unit 50 guides the container 10 to the discharge line.

7-1. Annular contour The annular contour 18a at the upper left of FIG. 6 is a detected object in which the recognized shapes of the detected objects are connected in an annular shape. As illustrated in FIG. 7, the determination unit 52 recognizes at least one detection object from the captured image 80 (FIG. 3), and detects the detection object when the recognized detection object is a ring-shaped detection object. A defect can be determined based on the area relating to the body. By making such a determination, it is possible to determine a detection object having the annular contour 18a as a defect and determine the container 10 having the defect as a defective product.

  When the detection object has the annular contour 18a, an inspection area 81 including the entire annular contour 18a is set, and the area of the annular contour 18a inside the inspection area 81 and the area surrounded by the annular contour 18a are set. When the area obtained by adding the area of the range is equal to or larger than a predetermined threshold value, the annular contour 18a is determined to be a defect, and the container 10 is determined to be defective. When it is determined whether or not a defect (thin bubble) is present only by the area of the annular contour 18a, it is possible to determine that even a small-sized detection object based on the flesh unevenness 19 remaining even after image processing is a defect. This is to prevent this.

7-2. Divided Contours The two types of divided contours 18b in the middle part of FIG. 6 are the detected objects in which the shape of the recognized object is divided into a plurality of shapes and recognized. The left divided contour 18b is divided into two, and the right divided contour 18b is divided into four. Since such a division cannot be recognized as the annular contour 18a, a process different from that of 7-1 is required.

  As illustrated in FIG. 7, the determination unit 52 recognizes at least one detection object (the divided contour 18b) from the captured image 80 (FIG. 3), and vertically determines a predetermined range including the recognized detection object. A vertical inspection area 82 extending in the direction Y and a horizontal inspection area 84 extending in the horizontal direction X are set, and the vertical inspection area 82 and the horizontal inspection area 84 include two or more detection objects (divided contours 18b). In this case, it can be determined as a defect. A detected object whose outline has been divided and recognized can also be determined as a defect.

  In the vertical inspection area 82, for example, the width in the horizontal direction X is set according to the width in the horizontal direction X of one divided contour 18b, and the height in the vertical direction Y is three divided contours 18b. Set according to height.

  The horizontal inspection area 84 has a height in the vertical direction Y set according to one divided contour 18b, and a width in the horizontal direction X set according to the width of three divided contours 18b.

7-3. Arc-shaped contour The arc-shaped contour 18c on the lower left side of FIG. 6 is a detected object whose shape of the detected object is an arc. Such an arc-shaped contour 18c requires a different process from that of 7-1 and 7-2.

  As illustrated in FIG. 7, the determination unit 52 recognizes at least one detection object from the captured image 80 (FIG. 3), and, when the shape of the recognized detection object is an arc-shaped detection object, determines the detection object ( A defect can be determined based on the area of the arcuate contour 18c). By making such a determination, the detection object having the arc-shaped contour 18c can be determined as a defect, and the container 10 having the defect can be determined as a defective product.

  When the detection object has the arc-shaped contour 18c, the circumscribed inspection area 85 circumscribing the arc-shaped contour 18c is set, and the area ratio of the area of the arc-shaped contour 18c to the area of the circumscribed inspection area 85 is equal to or more than a predetermined threshold. In this case, the arc-shaped contour 18c is determined to be a defect, and the container 10 is determined to be defective. When it is determined whether or not a defect (thin bubble) is present only by the area of the arc-shaped contour 18c, it is possible to determine that even a small-sized detection object based on the flesh unevenness 19 remaining even after image processing is a defect. This is to prevent this.

7-4. Bright part A bright part 18d on the lower right side of FIG. 6 is a part having a luminance equal to or higher than a predetermined threshold value near a detection object (for example, an annular contour 18a).

  As illustrated in FIG. 7, the determination unit 52 recognizes at least one detection object (for example, the annular contour 18a) from the captured image 80 (FIG. 3), and sets a predetermined range including the recognized detection object in a predetermined range. When a portion having a brightness equal to or higher than the predetermined threshold (the bright portion 18d) is included, the container 10 can be determined to be defective. Even a detection object including a place where the contour is bright and a place where the contour is dark can be determined as a defect. This is because dirt or the like has only a dark portion, but in the case of a shape like the thin bubble 18, there may be a bright portion 18 d, so that the thin bubble 18 can be recognized as a thin bubble 18 even if its outline is small.

  The type of the detection object may be the divided outline 18b or the arc-shaped outline 18c.

8. Inspection Method In the inspection method of the container 10 according to the present embodiment, the light emitted from the light emitting unit 20 and the blind 243 extending in the horizontal direction X limit the incident angle of the light from the light emitting unit 20 with respect to the vertical direction Y. The light passing through the dimming unit 242 is alternately irradiated to the container 10 in the vertical direction Y, and the image 80 of the container 10 is captured by the imaging unit 40 arranged to face the light emitting unit 20 with the container 10 interposed therebetween. It is characterized in that an image is taken and bubbles on the inner surface 15 of the container 10 are determined as defects.

  According to the method of inspecting the container 10, the presence or absence of a detection object such as a thin bubble 18 whose contour is unclear can be inspected by a change in luminance in the vertical direction of the container surface due to the light transmitting portion and the light reducing portion.

  An inspection method employing the inspection device 1 will be described with reference to FIGS. FIG. 8 is a flowchart of the method of inspecting the container 10.

  S10: The control unit 50 issues a command to the rotation control unit 62 to drive the motor 60 to rotate the rotation support unit 30 and the side rollers 32 at a predetermined speed. The container 10 conveyed to the inspection position starts rotating around the axis 12 due to the rotation of the rotation support portion 30 and the side roller 32.

  S20: The control unit 50 instructs the imaging unit 40 to start imaging. The imaging unit 40 calculates the rotation angle of the container 10 based on the output from the rotation detection unit 54 in accordance with a command from the control unit 50, and photographs the entire circumference of the trunk 13.

  S30: The control unit 50 instructs the image processing unit 53 to store the image 80 in a storage unit (not shown). The image processing unit 53 stores the image 80 of at least one round (for example, 1.5 rounds) of the container 10.

  S40: The control unit 50 causes the determination unit 52 to determine the presence or absence of the detected object in the stored image 80. As a result of the determination, when there is no detected object in the image 80, the processing of the determination unit 52 ends, and the container 10 is transported to the next process as a non-defective product. In addition, as a result of the determination, when there is a detected object in the image 80, the following four inspection algorithms are executed.

  S50 (first inspection algorithm): the determination unit 52 recognizes at least one detection object from the captured image 80, and the shape of the recognized detection object is an annularly connected detection object (annular contour 18a). Then, the detection object is determined to be a defect based on the area of the detection object. The details of the inspection have been described in the section 7-1 and will not be repeated.

  S60 (second inspection algorithm): the determination unit 52 recognizes at least one detection object (divided contour 18b) from the captured image 80, and moves in the vertical direction Y to a predetermined range including the recognized detection object. When a vertical inspection area 82 extending and a horizontal inspection area 84 extending in the horizontal direction X are set, and the vertical inspection area 82 and the horizontal inspection area 84 include two or more detection objects (divided contours 18b), The detected object is determined as a defect. The details of the inspection have been described in the section 7-2, and will not be repeated.

  S70 (third inspection algorithm): The determination unit 52 recognizes at least one detection object from the captured image 80 (FIG. 3), and, if the shape of the recognized detection object is an arc-shaped detection object, determines the detection object. The detected object is determined to be a defect based on the area related to the (arc-shaped contour 18c). The details of the inspection have been described in the section 7-3, and will not be repeated.

  S80 (fourth inspection algorithm): The determining unit 52 recognizes at least one detection object (for example, the annular contour 18a) from the captured image 80, and sets a predetermined threshold in a predetermined range including the recognized detection object. If a portion having a brightness equal to or greater than the value (the bright portion 18d) is included, the detected object is determined to be a defect. The details of the inspection have been described in the section 7-4, and will not be repeated.

  S90: If the determination unit 52 determines that the detected object is a defect in any of the first inspection algorithm to the fourth inspection algorithm, the discharging process (S100) is executed, and if it is determined that the detected object is not a defect, Terminates the processing of the determination unit 52, and the control unit 50 conveys the container 10 to the next step.

  S100: The control unit 50 discharges the defective container 10 determined by the determination unit 52 to have a defect from a discharge unit (not shown) different from the transport path to the next process.

  The present invention is not limited to the embodiments described above, and various modifications are possible. For example, the invention includes substantially the same configuration as the configuration described in the embodiment (for example, a configuration having the same function, method, and result, or a configuration having the same object and effect). The invention also includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. Further, the invention includes a configuration having the same operational effects as the configuration described in the embodiment or a configuration capable of achieving the same object. Further, the invention includes a configuration obtained by adding a known technique to the configuration described in the embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Inspection apparatus, 10 ... Container, 11 ... Mouth, 12 ... Axis, 13 ... Trunk, 13a ... Lower area, 13b ... Upper area, 14 ... Bottom part, 15 ... Inner surface, 16 ... Seam, 18 ... thin bubble, 18a ... annular contour, 18b ... divided contour, 18c ... arcuate contour, 18d ... bright part, 19 ... flesh unevenness, 20 ... light emitting part, 22 ... light emitting surface, 24 ... first light limiting part 242: dimming part, 243: blind, 244: light transmitting part, 246: long hole, 26: second light restricting part, 264: long hole, 28: bolt, 30: rotation support part, 32: side roller, 35 belt, 40 imaging unit, 50 control unit, 52 determination unit, 53 image processing unit, 54 rotation detection unit, 60 motor, 62 rotation control unit, 80 image, 81 inspection area, 82 vertical inspection area 84 horizontal inspection area 85 circumscribed inspection area H1 ... predetermined height position, H2 ... height, W ... width

Claims (9)

A light emitting unit having a light emitting surface for irradiating the container with light,
An imaging unit arranged opposite to the light emitting unit with a container interposed therebetween,
A determining unit that determines the presence or absence of a defect based on the image of the container captured by the imaging unit;
A light restricting unit disposed on the container side of the light emitting unit,
Including
The light restricting unit includes a light transmitting unit and a light reducing unit extending in a horizontal direction along the light emitting surface,
The light transmitting portion and the light reducing portion are alternately arranged in the vertical direction,
The light transmitting unit transmits light emitted from the light emitting unit to the container side,
The light reducing unit includes a plurality of blinds extending in the horizontal direction in the vertical direction, and of the light emitted from the light emitting unit, limits an incident angle of the light with respect to the vertical direction. Container inspection equipment. In claim 1,
The apparatus for inspecting a container, wherein the dimming unit is disposed on a light emitting surface of the light emitting unit, and has a height from the light emitting surface of 0 mm to 100 mm. In claim 1 or 2,
The container inspection apparatus according to claim 1, wherein the width of the light transmitting portion in the vertical direction is 3 mm to 6 mm. In any one of claims 1 to 3,
The said dimming part is formed by laminating a plurality of light control films, The container inspection apparatus characterized by the above-mentioned. In any one of claims 1 to 4,
The light restricting unit is a first light restricting unit disposed at a position corresponding to a region below the predetermined height position of the container in the vertical direction,
On the container side of the light emitting unit, at a position corresponding to an area above the predetermined height position, further includes a second light restricting unit that reduces a transmission amount of light emitted from the light emitting unit,
The two second light restricting units are arranged at a predetermined interval in the horizontal direction, and the container inspection apparatus is characterized in that: In any one of claims 1 to 5,
The determination unit recognizes at least one detection object from the captured image, and sets the vertical inspection region extending in the vertical direction and the horizontal inspection region extending in the horizontal direction in a predetermined range including the recognized detection object. A container inspection apparatus characterized in that when two or more detection objects are included in the vertical inspection area and the horizontal inspection area, a defect is determined. In any one of claims 1 to 6,
The determination unit recognizes at least one detection object from the captured image, and determines a defect based on an area related to the detection object when the shape of the recognized detection object is a ring-shaped detection object or an arc-shaped detection object. A container inspection device, characterized in that: In any one of claims 1 to 7,
The determination unit recognizes at least one detected object from the captured image, and determines a defect when a predetermined range including the recognized detected object includes a portion having a brightness equal to or higher than a predetermined threshold. A container inspection device, characterized in that: The light emitted from the light emitting unit and the light passing through the dimming unit that limits the incident angle of the light from the light emitting unit with respect to the vertical direction by the blind extending in the horizontal direction, and alternately in the container in the vertical direction. And irradiate
An image of the container is captured by an imaging unit arranged opposite to the light emitting unit with the container interposed therebetween,
A method for inspecting a container, wherein a bubble on the inner surface of the container is determined as a defect.