JP2017030760A - Inspection device, inspection method, container with label, and shrink label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shrink label that is capable of reducing erroneous detection during inspection of a mounted state of the shrink label.SOLUTION: A cylindrical shrink label L put over a cup-like container from a bottom surface side and thermally shrunk by heating to be mounted to a side surface part and a bottom surface part of the cup-like container is formed in such a manner that an inspection mark 13 for inspection of a mounted state of the shrink label L, which becomes ring-shaped along a peripheral edge of the bottom surface part of the cup-like container, is provided at one end part in parallel to a label end surface, and further a designation mark 16 for designating a portion to be excluded from inspection during the inspection, which is a part of the inspection mark 13 in a peripheral direction, is provided. The portion designated by the designation mark 16 is excluded from an inspection target during the inspection of the mounted state of the shrink label L, and thus by designating a portion in which misalignment of the inspection mark 13 occurs by the designation mark 16, erroneous detection caused by the misalignment can be reduced.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an inspection apparatus and an inspection method for inspecting a mounting state of a shrink label attached to a cup-shaped container by heat shrinking in a radial direction of the cup-shaped container, for example, on a side surface and a bottom surface of the cup-shaped container. , Labeled containers and shrink labels.

  Conventionally, containers that can be filled with beverages or foods have been proposed. Such containers are usually fitted with a transparent or opaque label having a pattern representing the contents filled therein. An inspection device for inspecting whether the label is properly attached to the container has been developed.

  For example, there is a case in which a shrink label that is thermally contracted is attached to a so-called cup-shaped container in which the area of the bottom surface is smaller than the area of the opening surface, and in addition to the side surface of the cup-shaped container, the bottom surface is also covered. is there. As an inspection apparatus for cup-shaped containers (hereinafter referred to as “labeled containers”) equipped with such shrink labels, an inspection apparatus for inspecting the bottom surface of a labeled container has been developed (Patent Document 1, etc.) reference).

  The inspection apparatus described in Patent Document 1 images the bottom surface portion of a labeled container, and inspects the mounting state of the shrink label based on the shape of a ring-shaped inspection mark provided on the bottom surface portion. The inspection apparatus determines whether the mounted state is good or not based on whether or not the distance from the center of the bottom surface of the labeled container to the inspection mark is within a predetermined range.

Patent No. 4627257

  However, in the inspection apparatus described in Patent Document 1, even if the mounting state is appropriate, it may be determined that the mounting is defective. The shrink label before being mounted is a film in which a printed film is formed in a cylindrical shape. In the step of forming both sides of the film together to form a cylinder (center seal step), adjustment is made so that the axial shift of the bonded portion falls within a predetermined range. On the shrink label, an inspection mark that is ring-shaped along the periphery of the bottom surface when attached to the cup-shaped container is printed so as to be orthogonal to the attachment direction. In the center sealing process, even when the bonding is performed so that the axial displacement is within a predetermined range, the axial displacement may occur at the bonded portion of the inspection mark. In this case, even if the shrink label is properly attached, it may be determined that the attachment is defective because the distance from the center of the bottom surface of the labeled container to the inspection mark is outside a predetermined range.

  As the shrink label is made thinner and the diameter of the container with the label is increased (the shrink label is increased in size), a shift in the axial direction is likely to occur in the bonded portion of the inspection mark. In addition, as the standard of inspection by the inspection mark (allowable range of the distance from the center of the bottom surface of the labeled container to the inspection mark) becomes stricter, the possibility of erroneous detection increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an inspection apparatus and an inspection method that can reduce erroneous detection in an inspection of a shrink label mounting state. Moreover, it aims at providing the container with a label applied to the test | inspection apparatus, and the shrink label applicable to the container with a label.

  The shrink label provided by the first aspect of the present invention is covered with a cup-shaped container from the bottom surface side, and is heat-shrinked when heated to be attached to the side surface portion and the bottom surface portion of the cup-shaped container. A shrink label, which when attached to the cup-shaped container, has a ring-shaped inspection mark along the peripheral edge of the bottom surface portion of the cup-shaped container, and is provided at one end parallel to the label end surface. And a designation mark for designating a part of the inspection mark in the circumferential direction is further provided.

  In a preferred embodiment of the present invention, the shrink label has a cylindrical shape in which both side edges of the heat-shrinkable film are bonded to each other, and the designation mark designates a bonding position of the inspection mark. .

  In a preferred embodiment of the present invention, the designation mark has a linear shape extending in a direction substantially orthogonal to the inspection mark.

  In a preferred embodiment of the present invention, the designation mark is a symbol or character provided at a position adjacent to the inspection mark.

  In a preferred embodiment of the present invention, the designation mark is a portion printed on the inspection mark with an ink different from the ink on which the inspection mark is printed.

  In a preferred embodiment of the present invention, the designation mark is printed with ultraviolet light emitting ink.

  In a preferred embodiment of the present invention, the designation mark is a missing portion of the inspection mark.

  In a preferred embodiment of the present invention, the inspection mark is provided for inspecting the mounted state of the shrink label, and the designation mark designates a portion to be excluded from the inspection at the time of the inspection. belongs to.

  In a preferred embodiment of the present invention, a predetermined section in the circumferential direction based on the position of the inspection mark designated by the designation mark is a portion excluded from the inspection at the time of the inspection.

  In a preferred embodiment of the present invention, two specified marks are provided, and a predetermined interval in the circumferential direction with reference to an intermediate position between the positions of the inspection marks respectively specified by the two specified marks. Is a part excluded from the inspection at the time of the inspection.

  In a preferred embodiment of the present invention, two designation marks are provided, and a section between the positions of the inspection marks respectively designated by the two designation marks is excluded from the inspection at the time of the inspection. This is the part.

  The labeled container provided by the second aspect of the present invention is a labeled container in which a shrink label is attached by heat shrinking to the side surface and the bottom surface of the cup-shaped container, and the bottom surface is provided with the bottom surface. A ring-shaped inspection mark along the periphery of the part and a designation mark for designating a part of the inspection mark in the circumferential direction are formed.

  The inspection apparatus provided by the third aspect of the present invention inspects the mounted state of the shrink label on the cup-shaped container in the labeled container formed by thermally shrinking the shrink label on the side surface and bottom surface of the cup-shaped container. In the inspection apparatus, the bottom surface portion of the labeled container is for specifying a ring-shaped inspection mark along the periphery of the bottom surface portion and a part of the inspection mark in the circumferential direction. A designated mark is formed, an imaging unit that images the bottom surface of the labeled container, an image processing unit that extracts an outline shape of the inspection mark from an image captured by the imaging unit, and the image processing Determining means for determining whether or not the shrink label is attached based on the contour shape of the inspection mark extracted by the means, , When determination of the mounted state, said the portion specified by the specified mark, and performing discrimination and excluded from inspection.

  The inspection method provided by the fourth aspect of the present invention is to inspect the attached state of the shrink label on the cup-shaped container in the labeled container formed by thermally shrinking the shrink label on the side surface and bottom surface of the cup-shaped container. An inspection method for specifying a ring-shaped inspection mark along a peripheral edge of the bottom surface portion and a part of the inspection mark in the circumferential direction on the bottom surface portion of the labeled container. A first step of imaging the bottom surface of the labeled container, and a second step of extracting the contour shape of the inspection mark from the image captured in the first step. And a third step of determining whether or not the shrink label is attached based on the contour shape of the inspection mark extracted in the second step. In the third step, Serial upon determination of the mounted state, said the portion specified by the specified mark, and performing discrimination and excluded from inspection.

  According to the present invention, it is possible to exclude a portion specified by the designation mark from the inspection target in the inspection of the mounted state of the shrink label by the inspection mark. Therefore, if the bonding portion of the inspection mark is designated by the designation mark, it is possible to reduce erroneous detection based on the axial deviation of the bonding portion.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

It is a lineblock diagram showing an outline of an inspection device concerning this embodiment. It is a figure for demonstrating the container with a label which concerns on this embodiment. It is a figure which shows a state when a shrink label is inserted by the cup-shaped container. It is a figure for demonstrating the formation method of a shrink label. It is a figure which shows a state when a shrink label adheres to a cup-shaped container. It is a figure which shows an example of the image imaged with an imaging device. It is a figure for demonstrating the case where the distance of the point in image data and the image center is calculated. It is a figure which shows the graph showing the distance from the image center of image data. It is a figure which shows the graph showing the distance from the image center of image data, and shows when the image data is out of a predetermined allowable range. It is a figure which shows an example in the state in which the shrink label is not suitably mounted | worn with respect to the cup-shaped container. It is a figure for demonstrating the defect discrimination | determination in an image processing apparatus when the designation | designated mark is not provided and the axial shift | offset | difference arises in the bonding part by the center sealing process. It is a figure for demonstrating the modification of the designation | designated mark which concerns on this invention. It is a figure explaining the mounting | wearing process in which a shrink label is mounted | worn with respect to a cup-shaped container. It is a figure which shows a mode when an image processing apparatus takes in an image.

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

  FIG. 1 is a configuration diagram illustrating an outline of an inspection apparatus according to the present embodiment. This inspection apparatus 1 is for inspecting the quality of the mounted state of the mounted shrink label L with respect to the labeled container A which is an object to be inspected. That is, the inspection device 1 inspects whether or not the shrink label L attached to the labeled container A is properly attached without being deviated from the normal position.

  As shown in FIG. 1, the inspection device 1 is imaged by an illumination device 2 for irradiating light to the labeled container A, an imaging device 3 for imaging the labeled container A, and the imaging device 3. The image processing apparatus 4 processes the converted image as image data, and determines whether the shrink label L is attached or not, and the display apparatus 5 for displaying an imaging screen of the imaging apparatus 3.

  Although the details will be described later, for example, the inspection device 1 is provided on a transport line 6 for mounting a shrink label L on the cup-shaped containers C while sequentially transporting the plurality of cup-shaped containers C at a predetermined interval. The image processing apparatus 4 is connected to a conveyance control device 7 that comprehensively controls various devices (described later) installed on the conveyance line 6. When the image processing device 4 detects the labeled container A in which the shrink label L is not properly attached, the image processing device 4 outputs the content to the transport control device 7. The conveyance control device 7 performs control for removing the defective labeled container A from the conveyance line 6 based on the output from the image processing device 4. The labeled container A is transported on the transport line 6 in a posture opposite to the posture normally used, that is, with the bottom surface portion 11 facing upward.

  The illuminating device 2 irradiates, for example, white light on the bottom surface portion 11 of the labeled container A from above, and from a fluorescent lamp formed in a substantially donut shape having a diameter larger than the diameter of the labeled container A. Become. In addition, the illuminating device 2 is not restricted to a fluorescent lamp, For example, the illuminating device in which several LED was arranged may be sufficient.

  In the illumination device 2, when the labeled container A transported on the transport line 6 passes below the illumination device 2, the center of the substantially donut-shaped illumination device 2 is approximately the center of the bottom surface portion 11 of the labeled container A. It is arranged at the matching position. Therefore, the illuminating device 2 can irradiate light uniformly to one surface of the bottom face part 11 of the labeled container A. The lighting device 2 is controlled by the image processing device 4 to turn on and off (normally on).

  The imaging device 3 is constituted by, for example, a CCD camera, and the imaging direction is determined in a direction in which the central hollow portion of the illumination device 2 formed in a substantially donut shape is looked at, that is, the imaging direction is substantially vertical. It is arranged to face. Thus, the imaging device 3 can reliably image the bottom surface portion 11 of the labeled container A by determining the imaging direction.

  The image processing device 4 processes an image picked up by the image pickup device 3, converts an image pickup signal (analog signal) output from the image pickup device 3 into a digital signal, and then a predetermined image memory (not shown). The image data as a digital signal is stored in the image data, and predetermined digital signal processing such as filter processing is performed on the image data. Further, the image processing device 4 determines whether or not the shrink label L is properly attached to the labeled container A based on the image data subjected to predetermined digital signal processing. This determination process will be described later. When a defective labeled container A to which the shrink label L is not properly attached is detected based on the image data, the image processing device 4 outputs the content to the transport control device 7.

  The display device 5 is for displaying the imaging state of the labeled container A, and is used when the user wants to visually observe the bottom surface portion 11 of the labeled container A. In addition, the display device 5 can also check whether the imaging device 3 and the like are in their original locations as necessary. That is, the display device 5 can confirm whether or not the center of the bottom surface portion 11 of the labeled container A coincides with the imaging center of the imaging device 3.

  The conveyance control device 7 controls the operation of each device (described later) installed on the conveyance line 6 in an integrated manner. The transport control device 7 is configured by a microcomputer including, for example, a CPU, a ROM, a RAM, and the like.

  When the conveyance control device 7 receives information from the image processing device 4 that, for example, a labeled container A to be removed from the conveyance line 6 has been detected, the conveyance control device 7 removes the container at the timing when it is conveyed to the position of the container removal device described later. The apparatus is operated to remove the labeled container A to be removed from the transfer line 6.

  FIG. 2 is a view for explaining a labeled container A applied to the inspection apparatus 1. Fig.2 (a) is a perspective view, and the bottom face part 11 of the labeled container A is represented facing upward. FIG. 2B is a view as seen from the bottom surface portion 11 side. In addition, the shape represented in FIG. 2, the magnitude | size and thickness of each part, those relative ratios, etc. differ from an actual dimension. For example, the inspection mark 13 and the designation mark 16 are written thicker than actual ones. The same applies to the other drawings.

  The container A with a label is a container in which a liquid such as drinking water or liquor, or a solid such as a cup noodle or miso soup can be stored. The labeled container A is formed in a substantially cup shape with one surface (the lower end surface shown in FIG. 2A) opened, and the material thereof is formed of, for example, a synthetic resin. Normally, a lid (not shown) is attached to the lower end opening surface of the labeled container A, and this lid is used by being attached to and detached from the labeled container A by the user as necessary. Moreover, the container A with a label may be used as a cup with the lower end opening surface still opened.

  A shrink label L provided so as to cover them is attached to a part of the side surface portion 12 and the bottom surface portion 11 of the labeled container A. That is, as shown in FIG. 3, this labeled container A is a cup-shaped container C with a substantially cylindrical shrink label L attached thereto. The inner diameter of the shrink label L is substantially the same as or slightly larger than the outer diameter of the lower end opening surface of the cup-shaped container C.

  The shrink label L is made of, for example, a polyester resin or a polystyrene resin, and is formed of a transparent or translucent film having a thickness of about 20 to 80 μm. As shown in FIG. 4, the shrink label L is formed by laminating both side edges of a long film into a substantially cylindrical shape and cutting it so as to be orthogonal to the long direction.

  FIG. 4A shows a long film on which predetermined printing has been performed. The film is printed with a strip-shaped inspection mark 13 extending in a direction orthogonal to the longitudinal direction and a linear designation mark 16 orthogonal to the inspection mark 13 apart from printing of the description of the product. Yes. The designation mark 16 is arranged at the boundary between the inspection mark 13 and the margin 17. Details of the inspection mark 13 and the designation mark 16 will be described later.

  FIG. 4B shows the other side edge portion (FIG. 4A) on the inner surface side of the marginal portion 17 which is a transparent portion of one side edge portion of the long film shown in FIG. These show the state formed in the substantially cylindrical shape by bonding the left edge part). The overlapping part of the margin part 17 and the other side edge part bonded to this becomes a bonding part. Since the margin part 17 is transparent in the pasted part, the printing of the other side edge part pasted on the inside is shown through. The inspection mark 13 is a bonded portion, and one end and the other end are connected to each other, and the inspection mark 13 has a ring shape continuous over the entire circumference of a long film formed in a cylindrical shape. Further, the designation mark 16 is a display for designating a bonded portion in the inspection mark 13.

  FIG. 4C shows a state in which the long film formed in a cylindrical shape shown in FIG. 4B is cut for each predetermined length to form a shrink label L. FIG. First, the long film may be cut into predetermined lengths, and the cut film may be formed into a cylindrical shape. The shrink label L generated in this way is inserted and inserted from the bottom surface side of the cup-shaped container C (see FIG. 3) in a label insertion step described later.

After the shrink label L is inserted into the cup-shaped container C, it is thermally shrunk in the radial direction of the cup-shaped container C in a shrinking process described later, whereby the side surface portion 12 and the bottom surface portion 11 of the cup-shaped container C. It is attached in close contact with a part of the surface. For example, the height H of the shrink label L shown in FIG. 3 is formed longer than the height H ₀ of the cup-shaped container C, and when the shrink label L is attached to the cup-shaped container C, the shrink label L is In addition to being in close contact with the side surface portion 12 of the cup-shaped container C, it is bent at the upper peripheral edge of the cup-shaped container C and is in close contact with the bottom surface portion 11 of the cup-shaped container C as shown in FIG.

  Further, as shown in FIG. 3, for example, a heat-sensitive adhesive 14 made of a solution mainly composed of a heat-adhesive resin is applied to the inside of the lower end of the shrink label L in advance. The shrink label L is heat-shrinked and comes into close contact with the cup-shaped container C. However, the heat-sensitive adhesive 14 can make the shrink label L adhere to the cup-shaped container C more reliably.

  On one side of the shrink label L, a portion La (see FIG. 3) extending from the central portion to the lower portion of the shrink label L, that is, a portion that is in close contact with the side surface portion 12 of the cup-shaped container C, represents a predetermined content representing the contained contents. The design is printed. Further, on one side of the shrink label L, an upper portion Lb (see FIG. 3) of the shrink label L, that is, a portion that is in close contact with the bottom portion 11 of the cup-shaped container C, has a belt-like shape along the periphery of the bottom portion 11. An inspection mark 13 is printed. By attaching the shrink label L to the cup-shaped container C, the inspection mark 13 becomes a ring shape at the bottom surface portion 11.

  The inspection mark 13 is used to determine whether or not the shrink label L is properly attached to the cup-shaped container C after the shrink label L is attached to the cup-shaped container C. As shown in FIG. 2B, the inspection mark 13 is composed of a plurality of concentric rings. The plurality of rings of the inspection mark 13 have different hues and are adjacent to each other. The first ring 13a disposed on the outermost side, the second ring 13b disposed on the inner side, and the innermost ring are disposed on the innermost side. It consists of a third ring 13c. In FIG. 2 (b), there is a film portion 15 on which the inspection mark 13 is not printed in the portion inside the third ring 13c, and the bottom portion 11 of the cup-shaped container C is exposed inside the portion. Yes.

  The width of each of the rings 13a to 13c is set to, for example, about 1 to 5 mm so that the imaging device 3 can capture an image, and the hue of the first ring 13a is, for example, white, and the second ring 13b is For example, it is black, and the third ring 13c is white, for example. In this way, by providing the inspection marks 13 in which the rings 13a to 13c are configured with colors having greatly different hues, for example, the black second ring 13b is in contrast to the white first ring 13a and the third ring 13c. To be clearly identified and reliably identified.

  That is, the labeled container A is imaged by the imaging device 3 from the bottom surface portion 11 side, whereby the inspection mark 13 printed on the shrink label L is also imaged. The captured image of the inspection mark 13 is output to the image processing device 4 for image processing, but the black second ring 13b is clearer than the white first ring 13a and the third ring 13c. In the image processing apparatus 4, the contour shape of the second ring 13b can be properly recognized as image data.

  Note that the inspection mark 13 is not limited to the combination of three colors such as white, black, and white as described above, but in the color scheme that can determine the mounting state of the shrink label L, that is, in the image captured by the imaging device 3. If a density difference is generated, various color combinations can be applied. The white, black, and white color schemes are for facilitating discrimination in the imaging device 3 and the image processing device 4 by making the black color of the second ring 13b stand out. Therefore, for example, even when the white color of the first ring 13a and the third ring 13c is gray and the black color of the second ring 13b is difficult to distinguish visually, the imaging performance of the imaging device 3 is high and the second ring 13b is If it is discriminable, such a color scheme may be used.

  Further, the color scheme such as white, black, white, and the like, when the labeled container A is imaged by the imaging device 3, the labeled container A is transparent, for example, so that the labeled line A can be seen through the transport line 6 and the labeled container. This is to prevent the color of the jig member 22 (described later) holding A from being indistinguishable. Therefore, for example, if the transport line 6 and the jig member 22 are white, the inspection mark may be provided with one black ring, for example. Further, if the entire labeled container A is, for example, white, the inspection mark may be provided with one black ring, for example.

  In addition, a linear designation mark 16 orthogonal to the inspection mark 13 is printed on the shrink label L (see FIG. 4C). The designation mark 16 is the same black as the second ring 13b of the inspection mark 13 so as to be clear with respect to the white first ring 13a and the third ring 13c. Note that the color of the designation mark 16 may not be the same color as the second ring 13b of the inspection mark 13. The designation mark 16 is for designating a part in the circumferential direction of the inspection mark 13. In the inspection using the inspection mark 13, the portion specified by the designation mark 16 in the inspection mark 13 is excluded from the inspection target.

  Note that the inspection mark 13 and the designation mark 16 may be printed with UV ink, for example, instead of printing with black or the like. The UV ink can be defined as a paint containing a pigment that emits and emits light by, for example, ultraviolet rays. However, the UV ink is not limited to UV ink as long as it emits and emits light by an electromagnetic wave in a region other than visible light. Absent. In this case, the imaging device 3 needs to be an imaging device capable of sensing UV ink.

  FIG. 6 is a diagram illustrating an example of images of the inspection mark 13 and the designation mark 16 captured by the imaging device 3. In the image of the inspection mark 13 and the designation mark 16 by the imaging device 3, as described above, the density of the second ring 13b and the designation mark 16 is higher than that of the first ring 13a and the third ring 13c. Since the density rapidly changes at the boundary between the designation mark 16 and the first ring 13a and the third ring 13c, the second ring 13b and the designation mark 16 are clearly expressed. It should be noted that in the image captured by the imaging device 3 (image output to the display device 5), the lower peripheral edge of the labeled container A and the peripheral edge of the bottom surface portion 11 are difficult to be displayed due to the irradiation condition by the illumination device 2 and the like. ing.

  In the image processing device 4, an image picked up by the image pickup device 3 is input and subjected to analog-digital conversion, and then the converted digital signal is temporarily stored in an image memory (not shown) as image data (pixel data). . Thereafter, by processing the image data stored in the image memory, the contour shapes of the inspection mark 13 and the designation mark 16 are extracted. That is, extraction of pixel data constituting the second ring 13b and the designation mark 16 is performed over the entire circumference of the bottom surface portion 11 of the labeled container A based on the density difference.

  In the extraction of the pixel data, as shown in FIG. 6, the pixel data constituting the second ring 13b and the designation mark 16 may be extracted within the range of the portion B represented by a substantially arc shape. . More specifically, among the pixel data stored in the image memory, for example, an angle α ° around the image center O from a reference line K (for example, a line along a direction orthogonal to the conveyance direction of the labeled container A). The pixel data constituting the second ring 13b and the designation mark 16 may be extracted from the pixel data in the range of the portion B represented by the substantially arc shape up to (in the case of the entire circumference, α = 360). °).

  For example, when the pixel data constituting the second ring 13b and the designation mark 16 has a lower level as the level density of the pixel data is higher, all pixel data over the entire circumference of the second ring 13b is set as a predetermined threshold value. By comparison, pixel data lower than the threshold is extracted as pixel data constituting the second ring 13b or the designation mark 16. Note that when the level density of the pixel data is higher, the higher the level, the lower the pixel data that is higher than the threshold value is extracted as the pixel data constituting the second ring 13b or the designation mark 16. Needless to say.

When the pixel data constituting the second ring 13b and the designation mark 16 is extracted, the coordinates (orthogonal coordinates) of the pixel position of the pixel data are converted into the coordinates of the polar coordinates. In addition, as shown in FIG. 7, in the conversion from the orthogonal coordinates to the polar coordinates, when the coordinates of the point P with respect to the coordinate center O are (x, y), the distance D is calculated by √ (x ² + y ² ), The angle θ is calculated by cos ⁻¹ (y / D). Therefore, in FIG. 6, if the pixel position of the image center O is (xo, yo) and the pixel position of arbitrary pixel data (point P) constituting the second ring 13b is (xp, yp), the distance D is , √ [(xp−xo) ² + (yp−yo) ² ], and the angle θ is calculated by cos ⁻¹ [(yp−yo) / D].

  In the image processing device 4, the pixel data of the second ring 13 b from which the contour shape has been extracted has an angle θ from the reference line K on the horizontal axis and a distance from the image center O on the vertical axis, as shown in FIG. 8. It is represented on the graph indicated by D. Hereinafter, the graph is referred to as a “polar coordinate graph”.

  At this time, pixel data of a part of the circumferential direction of the second ring 13b of the inspection mark 13 designated by the designation mark 16 is excluded and is not represented on the graph. That is, the pixel data in the section is masked. FIG. 8 shows a section in which the area indicated by M is masked. A section to be masked is designated by a designation mark 16.

Based on the contour shape of the designated mark 16 registered in advance, the image processing apparatus 4 uses the pattern matching to align the front / rear and top / bottom positions, and then extracts the designated mark from the pixel data stored in the image memory by angle extraction by edge detection. 16 is searched. The image processing apparatus 4 has a circumferential position of the second ring 13b designated by the detected designation mark 16 (a position where the designation mark 16 and the second ring 13b intersect. Hereinafter, it is referred to as a “designated position”). Is identified. Then, pixel data located in a predetermined section centered on the designated position in the circumferential direction of the second ring 13b is masked. Specifically, the angle θ ₀ corresponding to the designated position is calculated, the distance D in the range of θ ₀ −θ ′ ≦ θ ≦ θ ₀ + θ ′ is not calculated, and is not displayed on the polar graph. The section to be masked changes in accordance with θ ′, and the section to be masked increases as θ ′ increases. Since the masked pixel data is not represented on the polar coordinate graph (see the area M shown in FIG. 8), the masked pixel data is not subject to discrimination described later.

  In the image processing device 4, based on the polar coordinate graph, it is determined whether or not the distance D from the image center O at the point P on the second ring 13b is within a predetermined allowable width W (see FIG. 8). . That is, as shown in FIG. 9, when the distance D ′ from the image center O at the point P ′ is small and deviates from the allowable width W (when the distance D ′ is equal to or less than the lower limit value defining the allowable width W). Alternatively, although not shown, when the distance D is large and deviates from the allowable width W (when the distance D is equal to or greater than the upper limit value defining the allowable width W), the image processing apparatus 4 determines that it is defective.

  That is, the shrink label L is heat-shrinked and is in close contact with the side surface portion 12 of the cup-shaped container C, and is bent at the peripheral edge portion of the bottom surface portion 11 (see FIG. 5), and is also in close contact with the bottom surface portion 11. At this time, when the shrink label L is not properly attached to the cup-shaped container C, for example, the shrink label L is shallowly attached to the cup-shaped container C (attached toward the bottom surface portion 11 side). In some cases, as shown in FIG. 10A, the diameter of the inspection mark 13 is smaller than that of the regular inspection mark.

  Further, for example, when the shrink label L is deeply attached to the cup-shaped container C (attached to the opening side), as shown in FIG. 10B, the diameter of the inspection mark 13 is a regular inspection. It becomes larger than that of the mark for use. Alternatively, for example, when the shrink label L is distorted and attached to the cup-shaped container C, as shown in FIG. 10C, the inspection mark 13 does not become a perfect circle, for example, has a substantially elliptical shape, and It will be biased towards either rim. The form in which the inspection mark 13 deviates from the regular inspection mark is not limited to these forms.

  As described above, when the shrink label L is not properly attached to the cup-shaped container C, the inspection mark 13 becomes smaller, larger, or distorted than the regular inspection mark. The shape changes. In such a case, the point P in the pixel data of the second ring 13b from which the contour shape has been extracted falls outside the allowable width W, and the image processing apparatus 4 uses the shrink label L in the labeled container A. It is determined that the cup-shaped container C is not properly mounted, and the labeled container A is detected as a defective product. Therefore, by performing image processing on the image of the inspection mark 13 on the bottom surface portion 11 of the labeled container A, whether or not the shrink label L is attached to the cup-shaped container C based on the changing shape of the inspection mark 13 is determined. Can be detected easily and reliably.

  Further, when the image processing apparatus 4 determines a defect, the masked portion of the second ring 13b is excluded from the determination target. That is, for the pixel data of the masked portion, the distance D from the image center O is not calculated, and it is not determined whether or not it is within the allowable width W (see FIG. 8).

  FIG. 11 is a diagram for explaining defect determination in the image processing apparatus 4 when the designation mark 16 is not provided and an axial shift occurs in the bonded portion in the center sealing process.

  FIG. 11A shows a state in which the labeled container A, to which the shrink label L having a shift in the axial direction at the bonded portion is mounted, is viewed from the bottom surface portion 11 side. As shown in the figure, the inspection mark 13 is also displaced at the bonded portion.

  FIG. 11B shows a partially enlarged view of a polar coordinate graph created by imaging the bottom surface portion 11 of the labeled container A shown in FIG. 11A and performing image processing with the image processing device 4. In FIG.11 (b), the vicinity of the part applicable to a bonding part is expanded. At the point P shown in the figure, the distance D (distance from the center of the image) is small and is below the lower limit value that defines the allowable width W and deviates from the allowable width W. Therefore, in this case, even if the shrink label L is appropriately attached to the cup-shaped container C in the labeled container A, the labeled container A is determined as a defective product.

  However, if the designation mark 16 is provided and the bonded portion of the inspection mark 13 is designated, the region M shown in FIG. 11B is masked. Therefore, since the point P that will deviate from the allowable width W is excluded from the discrimination target, the labeled container A is not discriminated as a defective product.

  The larger the section to be masked, the more the false detection based on the axial displacement of the bonded part can be reduced, but conversely, even when the shrink label L is not properly attached, it is determined that it is appropriate. This is likely to cause false detection (false detection of mounting failure). For example, when the section to be masked is the area M shown in FIG. 9, it can be determined that the shrink label L is not properly mounted in the portion that has not been masked. However, if the section for masking is the region M ′ shown in FIG. 9, it is impossible to determine that the shrink label L is not properly attached in the portion that is not masked. Therefore, the section for masking needs to be set in consideration of the balance between the reduction of erroneous detection based on the axial deviation of the bonded portion and the reduction of erroneous detection of mounting failure.

  According to the present embodiment, the designation mark 16 designates a bonded portion in the inspection mark 13 (second ring 13b). Pixel data of a part of the circumferential direction of the inspection mark 13 (second ring 13b) designated by the designation mark 16 is masked and excluded from the inspection target in the mounting state inspection. That is, the vicinity of the bonded portion of the inspection mark 13 (second ring 13b) is not an inspection target in the mounted state. Therefore, although the shrink label L is properly attached, it is possible to reduce erroneous detection that it is determined that the attachment is defective due to the shift of the bonded portion in the center seal process.

  In the image processing described above, the discrimination processing is performed using the pixel data of the entire circumference of the inspection mark 13 in the image of the bottom surface portion 11 of the labeled container A, but as described above, from the reference line K A substantially arc-shaped portion B up to a predetermined angle α ° may be extracted and converted into pixel data for image processing. According to this image processing, there is an advantage that the control becomes easier as compared with the case where the entire circumference of the inspection mark 13 is converted into image data. However, in this case, it is necessary to be able to determine whether or not the shrink label L is appropriately attached to the labeled container A only by the substantially arc-shaped portion B.

  Further, the condition that the labeled container A is defective is not limited to the above-described condition. For example, among the pixel data of the second ring 13b from which the contour shape is extracted, pixel data of a predetermined ratio has the allowable width W. It may be a case where it comes off.

  In the above-described image processing, the determination is made based on whether or not the distance D from the image center O is within the allowable width W, but the present invention is not limited to this. For example, you may make it discriminate | determine based on the distance of the 2nd ring 13b and the periphery of the bottom face part 11 of the container A with a label. Further, the model image of the second ring 13b when the shrink label L is properly attached and the image of the second ring 13b imaged by the imaging device 3 are overlapped, and based on the area of the overlapping area. The determination may be made.

  In the image processing described above, the distance D is not calculated in the section where masking is performed, but the distance D is calculated for all sections, and the distance D is not referred to in the section where masking is performed in the wearing state inspection. (Or, it is not determined whether or not it is within the range of the allowable width W).

  The designation mark 16 is not limited to a line segment intersecting with the second ring 13b, and may be any mark that can designate the circumferential position of the inspection mark 13 (second ring 13b). For example, as shown in FIG. 12A, the designation mark 16 may have a linear shape protruding only on the first ring 13a side, or conversely, a linear shape protruding only on the third ring 13c side. The designation mark 16 may be a symbol such as a triangle (see FIG. 12B) or a round shape, or may be a character (see FIG. 12C). Alternatively, a missing portion (outlined portion) may be provided in the second ring 13b and used as the designation mark 16 (see FIG. 12D). Alternatively, a part of the second ring 13b may be provided with a different color portion, which may be used as the designation mark 16. Further, printing with UV ink may be added to a part of the second ring 13b to make it a designated mark 16, or the designated mark 16 may be printed with UV ink. In this case, since it cannot be seen with the naked eye, the designation mark 16 can be provided so as not to be noticed by the consumer. Also, as shown in FIG. 12 (e), two designation marks 16 may be provided to designate the intermediate position.

  The section in which masking is performed is not limited to the case where the position designated by the designation mark 16 is set as the center. For example, a section where masking is performed may be set in one direction from the position designated by the designation mark 16. In addition, as shown in FIG. 12E, two designation marks 16 may be provided, and a section between positions designated by the two designation marks 16 may be set as a section where masking is performed. .

  Next, the mounting process in which the shrink label L is mounted on the cup-shaped container C will be described with reference to the schematic diagram shown in FIG.

  The cup-shaped container C is attached with the shrink label L in the procedure shown in FIG. In this mounting step, a transport conveyor 21 is used for sequentially transporting the plurality of cup-shaped containers C at a constant transport speed and at a predetermined interval. The transport conveyor 21 is configured to transport the cup-shaped containers C in a row continuously, and the transport conveyor 21 is provided with a plurality of jig members 22 for fitting and holding the cup-shaped containers C. The jig member 22 is formed in a substantially truncated cone shape so that the cup-shaped container C can be easily held, and has a flange portion 22 a that abuts and supports the cup-shaped container C on the lower periphery. In addition, although not shown in figure, the conveyance conveyor 21 is formed in cyclic | annular form, for example.

  This mounting step is a container fitting step (see FIGS. 13A and 13B) in which the cup-shaped container C is fitted into the jig member 22 in the conveyance path from the upstream side to the downstream side of the conveyance conveyor 21. A label insertion process for inserting the shrink label L into the cup-shaped container C (see FIG. 13C), a shrinking process for thermally shrinking the shrink label L and closely contacting the cup-shaped container C (see FIG. 13D) , An inspection process for inspecting the mounting state of the shrink label L on the cup-shaped container C (see FIG. 13E), and a defect removal process for removing the defective labeled container A from the conveyor 21 (FIG. 13F). And a discharging process (not shown) for discharging the non-defective labeled container A from the conveyor 21.

  In the cup-like container C (the container A with label) in which the shrink label L is heat-shrinked and attached in the label insertion process and the shrinking process, the attached state of the shrink label L is inspected in the inspection process. When A is detected, it is removed from the conveyor 21 in the defect removal step. On the other hand, when a non-defective labeled container A is detected in the inspection process, it is discharged from the transport conveyor 21 to the next process (not shown) (for example, a packing process) in the discharge process. Hereinafter, the mounting process of the shrink label L will be described with reference to the schematic diagram shown in FIG.

  First, the cup-shaped container C to which the shrink label L is not attached is sequentially supplied to the jig member 22 provided on the conveyor 21 in the container insertion process shown in FIGS. The cup-shaped container C supplied to the jig member 22 in the container insertion process is transported by the transport conveyor 21, and the shrink label L is inserted in the label insertion process shown in FIG.

  In the label insertion process, after the shrink label L is inserted into the cup-shaped container C, a pressing mechanism for pressing the shrink label L downward and securely inserting the shrink label L into the cup-shaped container C. May be provided.

  The cup-shaped container C in which the shrink label L is inserted in the label insertion process is further conveyed by the conveyor 21 and the shrink label L is brought into close contact in the contraction process shown in FIG. That is, in the shrinking process, hot air is applied to the rotating mechanism (not shown) that rotates the jig member 22 while being conveyed, and the cup-shaped container C that is held by the jig member 22 and into which the shrink label L is inserted. A hot air heater (steam heater, not shown) or the like is provided.

  The hot air heater is heated by supplying hot air with the heat gun 16. The heat gun 16 moves upward while supplying hot air. Moreover, the cup-shaped container C hold | maintained at the jig member 22 rotates because the jig member 22 rotates with a rotation mechanism. Thereby, the shrink label L inserted in the cup-shaped container C is heated from the lower part to the upper part by the heat gun 16 while rotating. Therefore, the shrink label L is gradually heated from the lower part of the side part 12 of the cup-shaped container C to the bottom part 11 through the upper part, and is thermally contracted.

  The figure shown in FIG.13 (d) has shown the state which the shrink label L in the side part 12 of the cup-shaped container C is heated, and is thermally contracted. In FIG. 13D, the heat gun 16 is described as being provided in front of and behind the cup-shaped container C in the conveying direction of the cup-shaped container C, but actually, the heat gun 16 is orthogonal to the conveying direction. The hot air is supplied from the left and right sides of the cup-shaped container C.

  Since the heat-sensitive adhesive 14 is preliminarily applied to the inside of the lower end of the shrink label L, the shrink label L is more reliably cupped by the heat-sensitive adhesive 14 when thermally contracted in the shrinking process. In close contact with the container C.

  The cup-shaped container C (labeled container A) to which the shrink label L is in close contact in the shrinking process is inspected for the mounting state of the shrink label L on the cup-shaped container C in the inspection process shown in FIG. That is, it is inspected whether or not the shrink label L that is in close contact with the cup-shaped container C is attached without being displaced in the contraction process. In the inspection process, the above-described inspection device 1 (see FIG. 1) is provided, and the bottom surface portion 11 of the labeled container A is irradiated with light by the illumination device 2 and imaged by the imaging device 3.

  Here, since the labeled container A is continuously transported by the transport conveyor 21, when the center of the bottom portion 11 of the labeled container A coincides with the imaging center of the imaging apparatus 3, the label is labeled by the imaging apparatus 3. It is necessary to image the attached container A and the image processing apparatus 4 captures the image.

  FIG. 14 is a diagram showing a state when the image processing device 4 captures an image. The labeled container A is conveyed and the center of the bottom surface portion 11 of the labeled container A and the display center (imaging) of the display device 5 are illustrated. It is shown that the image processing apparatus 4 captures an image when it corresponds to the imaging center of the apparatus 3. That is, FIG. 14A shows a state in which the labeled container A is not within the display range S of the display device 5 (within the imaging range of the imaging device 3), and FIG. FIG. 14C shows a state where the container A has been transported and has entered the display range S of the display device 5, and FIG. 14C shows that the labeled container A is further transported and enters the display range S of the display device 5. The state when the center of the bottom face part 11 of the labeled container A and the display center of the display device 5 coincide is shown.

  A position sensor (not shown) for detecting a state when the center of the bottom surface portion 11 of the labeled container A and the display center of the display device 5 coincide with each other is provided at an appropriate position on the conveyor 21. Based on the output of the position sensor, the image processing device 4 captures an image captured by the imaging device 3 when the center of the bottom surface portion 11 of the labeled container A matches the display center of the display device 5. I have to.

  The image captured by the image processing device 4 is converted into image data and then subjected to image processing, and it is determined whether or not the shrink label L is properly attached to the cup-shaped container C. When a defective labeled container A to which the shrink label L is not properly attached is detected based on the image data, the image processing device 4 outputs the content to the transport control device 7.

  Of the labeled containers A picked up by the imaging device 3 and transported by the transport conveyor 21, the labeled containers A determined to be defective by the image processing device 4 are transport conveyors in the defect removal step shown in FIG. 21 is removed. That is, when the conveyance control device 7 receives from the image processing device 4 that the labeled container A to be removed from the conveyance conveyor 21 has been detected, the jig member 22 holding the labeled container A removes the container. The container removing device is operated at the timing when it is transported to the position of the device (not shown), and the defective labeled container A is removed from the transport conveyor 21. The container removing device includes, for example, a suction device for sucking the labeled container A held by the jig member 22.

  On the other hand, among the labeled containers A picked up by the image pickup device 3 and transferred by the transfer conveyor 21, the labeled containers A that are not determined to be defective by the image processing device 4 are not removed by the container removing device and are discharged. At the conveyor conveyor 21.

  Of course, the scope of the present invention is not limited to the embodiment described above. For example, in the above-described embodiment, the substantially cylindrical container A is exemplified as the labeled container A. However, the present invention is not limited to this, and for example, a rectangular labeled container A may be employed. In this case, as a determination criterion in the determination process of whether or not it is defective, a determination criterion corresponding to the rectangular labeled container A may be adopted.

  The inspection apparatus, inspection method, labeled container, and shrink label according to the present invention are not limited to the above-described embodiments. The specific configuration of each part of the inspection apparatus, the labeled container, and the shrink label according to the present invention can be varied in design in various ways.

DESCRIPTION OF SYMBOLS 1 Inspection apparatus 2 Illumination apparatus 3 Imaging apparatus 4 Image processing apparatus 5 Display apparatus 6 Conveyance line 7 Conveyance control apparatus 11 Bottom face part 12 Side face part 13 Inspection mark 13a 1st ring 13b 2nd ring 13c 3rd ring 14 Thermosensitive adhesive 15 Film part 16 Designation mark 17 Margin part 21 Conveyor 22 Jig member A Labeled container C Cup-shaped container L Shrink label W Allowable width

Claims (5)

A cylindrical shrink label that is put on the cup-shaped container from the bottom surface side and is thermally contracted by being heated and attached to the side surface and the bottom surface of the cup-shaped container,
When attached to the cup-shaped container, an inspection mark that is ring-shaped along the periphery of the bottom surface of the cup-shaped container is provided in parallel with the label end surface at one end,
A designation mark for designating a part of the inspection mark in the circumferential direction is further provided.
Shrink label characterized by that. A cylindrical shape in which both side edges of the heat-shrinkable film are bonded together,
The designation mark designates a bonding position of the inspection mark,
The shrink label according to claim 1. A container with a label on which a shrink label is attached by heat shrinking to the side and bottom of the cup-shaped container,
A ring-shaped inspection mark along the periphery of the bottom surface portion and a designation mark for designating a part of the inspection mark in the circumferential direction are formed on the bottom surface portion.
A labeled container characterized by that. In the labeled container formed by thermally shrinking the shrink label on the side surface and the bottom surface of the cup-shaped container, an inspection device for inspecting the mounting state of the shrink label on the cup-shaped container,
A ring-shaped inspection mark along the periphery of the bottom surface portion and a designation mark for designating a part of the inspection mark in the circumferential direction are formed on the bottom surface portion of the labeled container. And
Imaging means for imaging the bottom surface of the labeled container;
Image processing means for extracting the contour shape of the inspection mark from the image picked up by the image pickup means;
Based on the contour shape of the inspection mark extracted by the image processing unit, a determination unit that determines whether the shrink label is attached or not;
With
The determination means, when determining the mounting state, the portion specified by the specification mark is excluded from the inspection target, and determination is performed.
Inspection apparatus characterized by that. In the labeled container formed by thermally shrinking the shrink label on the side surface and the bottom surface of the cup-shaped container, an inspection method for inspecting the mounting state of the shrink label on the cup-shaped container,
A ring-shaped inspection mark along the periphery of the bottom surface portion and a designation mark for designating a part of the inspection mark in the circumferential direction are formed on the bottom surface portion of the labeled container. And
A first step of imaging the bottom surface of the labeled container;
A second step of extracting a contour shape of the inspection mark from the image captured in the first step;
A third step of determining whether or not the shrink label is attached based on the contour shape of the inspection mark extracted in the second step;
With
In the third step, when determining the mounting state, the part specified by the specification mark is excluded from the inspection target, and determination is performed.
Inspection method characterized by that.

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