Film package inspection device and film package inspection method

Abstract

To detect the turning-up of a film in a film package in which an article is packaged with a translucent film with high accuracy.SOLUTION: A film package inspection device 1 includes: a light irradiation unit 2 that has a first linear polarizing plate 22, emits linearly polarized light through the first linear polarizing plate 22, and irradiates a film package PK with the linearly polarized light; imaging means 3 that has a second linear polarizing plate 31 disposed at a position facing the light irradiation unit 2 with the film package PK interposed therebetween in an emission direction L1 of the light irradiation unit 2, suppresses passage of the linearly polarized light, and captures an image of the film package PK through the second linear polarizing plate 31; and a detection processing unit 4 that detects film curling of the film package by detecting an image portion of a curled film of the film package PK in the image.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a film package inspection apparatus and a film package inspection method for inspecting film packaging defects of a translucent film package in which an article is packaged with a translucent film.

Background Art

[0002] In recent years, in factory production lines, logistics warehouses, etc., many film packages in which the packaged items are packaged with a translucent film, such as integrated carton packages, are handled. Conventionally, methods for inspecting packaging defects of such film packages using imaging means such as optical sensors and cameras have been proposed (for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in recent years, as an aspect of packaging defects of film packages, "film curling (lifting)" in which the translucent film to be used for packaging the packaged item is in a state of being lifted from the packaged item due to "tearing" or the like has become a problem. In film curling, since the curled film portion is present away from the surface of the packaged item, for example, in the inspection methods using optical sensors and the conventional inspection methods using imaging by reflected light disclosed in Patent Documents 1 and 2, it is difficult to stably detect, and a method capable of detecting film curling with high accuracy has been demanded.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a film-packaged product inspection apparatus and a film-packaged product inspection method capable of detecting film curling in a film-packaged product in which an article is packaged with a translucent film with high accuracy.

Means for Solving the Problems

[0006] A film-packaged product inspection apparatus according to an aspect of the present disclosure is a film-packaged product inspection apparatus for detecting film curling in a film-packaged product in which an article is packaged with a translucent film, having a first linear polarizing plate, emitting linearly polarized light through the first linear polarizing plate, and irradiating the linearly polarized light onto the film-packaged product; an imaging means disposed at a position facing the light irradiation unit with the film-packaged product interposed therebetween in the emission direction of the light irradiation unit, having a second linear polarizing plate that suppresses the passage of the linearly polarized light, and imaging an image of the film-packaged product through the second linear polarizing plate; and a detection processing unit that detects film curling of the film-packaged product by detecting an image portion of the curled film of the film-packaged product in the image.

Effects of the Invention

[0007] According to an aspect of the present disclosure, it is possible to provide a film-packaged product inspection apparatus and a film-packaged product inspection method capable of detecting film curling in a film-packaged product in which an article is packaged with a translucent film with high accuracy.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0009] ≪Outline of Embodiments for Carrying Out the Present Invention≫ Hereinafter, the film-packaged product inspection apparatus and the film-packaged product inspection apparatus according to the embodiments in the present disclosure will be described. Note that, in the present disclosure, "film curling (warping)" refers to a state in which a translucent film covering the object to be packaged floats from the surface of the object to be packaged due to "tearing" or the like and does not completely cover the object to be packaged. Here, if there is "film curling" in the translucent film covering the object to be packaged, the object to be packaged is not blocked from the external atmosphere and is in a state of communicating with the external atmosphere through the location of "film curling", so it is determined as "packaging defect".

[0010] ​The film-packaged product inspection apparatus according to an embodiment of the present disclosure is a film-packaged product inspection apparatus that detects film curling of a film-packaged product in which an article is packaged with a translucent film, and has a first linear polarizing plate, emits linearly polarized light through the first linear polarizing plate, and irradiates the linearly polarized light onto the film-packaged product; an imaging unit that is disposed at a position facing the light irradiation unit with the film-packaged product interposed therebetween in the emission direction of the light irradiation unit, has a second linear polarizing plate that suppresses passage of the linearly polarized light, and captures an image of the film-packaged product through the second linear polarizing plate; and a detection processing unit that detects film curling of the film-packaged product by detecting an image portion of the curled film of the film-packaged product in the image.

[0011] With such a configuration, among the linearly polarized light emitted from the light irradiation unit, after passing through the first linear polarizing plate, the linearly polarized light is disrupted by the curled portion of the translucent film, and an image captured based on a component in a direction parallel to the polarization axis of the second linear polarizing plate, which is generated by light scattering, can be detected with high accuracy as an image portion indicating the curled film portion from the film-packaged product based on a high density difference from the surroundings. As a result, it is possible to provide a film-packaged product inspection apparatus that stably detects film curling in a film-packaged product with high accuracy.

[0012] In another aspect, in the aspect described above, the film-packaged product has a rectangular parallelepiped shape, and the detection processing unit may be configured to detect film curling on the outer surface of the film-packaged product by detecting an image portion of the curled film on the outer surface of the film-packaged product that faces the surrounding space and is parallel to the emission direction.

[0013] With such a configuration, it is possible to detect film curling on the outer surface of the film-packaged product by detecting an image portion of the curled film on the outer surface of the film-packaged product that faces the surrounding space and is parallel to the emission direction.

[0014] In another aspect, in any of the aspects described above, the detection processing unit may be configured to detect, based on the image, a package image region and an adjacent image region adjacent to the package image region, and detect, as an image portion of the curled film of the film package, a region having a luminance equal to or higher than a predetermined luminance and an area equal to or larger than a predetermined area in the adjacent image region.

[0015] With such a configuration, it is possible to specifically detect an image portion of the curled film on the outer surface of the film package parallel to the emission direction.

[0016] In another aspect, in any of the aspects described above, the detection processing unit may be configured to detect the orientation of the film package by detecting the shape and / or orientation of an image portion of the outer surface of the film package on the side opposite to the imaging means.

[0017] With such a configuration, when the shape and / or orientation of the film package is not normal, it is possible to determine that there is a packaging defect due to the film package being tilted or having the wrong orientation.

[0018] In another aspect, in any of the aspects described above, further provided is an illumination means for irradiating light onto the outer surface of the film package on the side opposite to the imaging means from an angle different from the emission direction, and the imaging means may be configured to capture an image of the film package by reflected light from the illumination means.

[0019] With such a configuration, the detection processing unit can perform a process of specifying a package image region based on the obtained image of the package and detecting film curling of the package.

[0020] In another aspect, the film package inspection method according to the embodiment is a film package inspection method for detecting film curling of a film package in which an article is packaged with a translucent film, the method including: a step of emitting linearly polarized light through a first linear polarizer and irradiating the linearly polarized light onto the film package; a step of imaging an image of the film package through a second linear polarizer that suppresses passage of the linearly polarized light from a position facing the light irradiation unit across the film package in the emission direction of the light irradiation unit; and a step of detecting film curling of the film package by detecting an image portion of the curled film of the film package in the image.

[0021] In another aspect, in any of the aspects described above, the film package is in a rectangular parallelepiped shape, and in the step of detecting the film curling, the film curling on the outer surface of the film package facing the surrounding space and parallel to the emission direction is detected by detecting an image portion of the curled film of the outer surface of the film package.

[0022] In another aspect, in any of the aspects described above, in the detecting step, based on the image, a package image region and an adjacent image region adjacent to the package image region are detected, and a region having a luminance equal to or higher than a predetermined luminance and an area equal to or larger than a predetermined area in the adjacent image region is detected as an image portion of the curled film of the film package.

[0023] With such a configuration, it is possible to realize a film package inspection method capable of stably detecting film curling in the package PK with high accuracy.

[0024] ≪Embodiment≫ The configuration of the film package inspection apparatus 1 according to the embodiment will be described with reference to the drawings. Here, in this specification, the X direction, Y direction, and Z direction in each figure may be the width direction, depth direction, and height direction, respectively, and the positive direction of the height direction may be the "up" direction and the negative direction may be the "down" direction.

[0025] Also, the scale of the members in each drawing is not necessarily the same as the actual one. Also, for the sake of easy understanding, illustrations such as covers may be omitted. Also, for example, some members, conveying paths, etc. may be illustrated schematically or approximately. Also, in this specification, the symbol "~" used when indicating a numerical range includes the numerical values at both ends thereof. Also, the materials, numerical values, etc. described in this embodiment are merely examples of preferable ones and are not limited thereto. Also, appropriate changes can be made without departing from the scope of the technical idea of the present disclosure. Also, combinations of some of the configurations with other embodiments are possible as long as no contradiction occurs.

[0026] <Configuration of Film Packaging Product Inspection Device 1> The configuration of the film packaging product inspection device 1 will be described with reference to the drawings. Fig. 1(a) is a plan view schematically showing the configuration of the film packaging product inspection device 1 (hereinafter sometimes referred to as "inspection device 1") according to the embodiment, (b) is a front view, and Fig. 2 is a side sectional view.

[0027] (Overall Configuration) The inspection device 1 is an inspection device for inspecting packaging defects in the film packaging product PK conveyed by the conveying means TM in a factory production line, a logistics warehouse, or the like. The inspection device 1 can detect "film winding", which is one aspect of the packaging defects in the film packaging product PK.

[0028] Here, "film curling" is a form of film packaging defect in a film packaging product PK where a part of the translucent film for packaging the object to be packaged is curled. As described above, it refers to a state where the translucent film covering the object to be packaged has lifted from the surface of the object to be packaged due to "tearing" or the like and does not completely cover the object to be packaged. Also, in "film curling", it suffices that the translucent film is in a state of lifting from the surface of the object to be packaged, and it is not necessary for the translucent film to be curled and turned inside out. Here, if there is "film curling" in the translucent film covering the object to be packaged, the object to be packaged is not blocked from the external atmosphere and is in a state of communicating with the external atmosphere through the "film curling" part, so it is determined to be "packaging defect".

[0029] As shown in FIG. 1, the inspection device 1 includes a light irradiation unit 2 that irradiates light onto the film packaging product PK transferred by the transfer means TM, an imaging means 3 that captures an image of the film packaging product PK, and a detection processing unit 4 that detects packaging defects of the film packaging product PK based on the obtained image. Further, it may be configured to include an illumination means 5 that irradiates light (L3) from an angle different from that of the light irradiation unit 2 onto the outer surface of the film packaging product PK on the side opposite to the imaging means 3, and to detect film curling of the film packaging product PK using the reflected light from the illumination means 5.

[0030] (Configuration overview of each part) Hereinafter, the configuration overview of each part in the inspection device 1 will be described. The film packaging product PK to be inspected by the inspection device 1 (hereinafter sometimes referred to as "packaging product PK") refers to a package in which an object to be packaged, such as a carton CT (packaging box) containing an article, is packaged with a translucent film. The object to be packaged includes not only regular objects with a fixed shape such as rigid bodies, but also irregular objects such as pillow packages having flexibility and a changing shape. The article may be of any type and use, such as a product, an intermediate product, or a member.

[0031] In this embodiment, as an example, the packaged product PK is an integrated carton formed by shrink-wrapping a plurality of one-stage rectangular parallelepiped cartons arranged side by side and / or stacked and arranged side by side with a light-transmitting film. Among the outer surfaces of such a packaged product PK, according to the inspection device 1, it is possible to detect film wrinkling on the outer surface of the packaged product PK facing the surrounding space and parallel to a predetermined direction.

[0032] For the light-transmitting film, for example, a polyester resin film, a polystyrene resin film, a polypropylene resin film, a polyvinyl chloride resin film, a polyolefin resin film, etc. can be used, and light-transmitting films made of other resins or materials can be widely used.

[0033] The conveying means TM is, for example, a conveyor for loading and conveying (T1) the packaged product PK to carry it into the process. Examples of the conveying means TM include various conveyors. Further, a passage detection means PS for detecting the passage of the packaged product PK may be arranged on the conveying path of the conveying means TM. For the passage detection means PS, for example, an optical sensor can be used.

[0034] The light irradiation unit 2 is a light-emitting unit that irradiates the packaged product PK with linearly polarized light. In this example, the light irradiation unit 2 is arranged on the back side (negative Y-axis direction) of the packaged product PK loaded on the conveying means TM and is configured to irradiate linearly polarized light toward the back surface of the packaged product PK (the surface opposite to the light irradiation unit 2). Here, in this specification, the light emission direction of the light from the light irradiation unit 2 is defined as the emission direction L1.

[0035] The light irradiation unit 2 includes a light-emitting unit 21 that emits light and a linear polarizing plate 22 (first linear polarizing plate) arranged in front of the emission direction L1 of the light-emitting unit 2 (in this example, the positive Y-axis direction).

[0036] For the light emitting unit 21, for example, a surface emitting LED light having a planar light emitting region may be used. The light emitting region of the light emitting unit 21 is set to an area and a position capable of irradiating light to a detection region R1 that is equal to or greater than the width of the carton CT included in the packaged product PK in the X direction and equal to or greater than the overall height of the carton CT in the Z direction. By using a device having a planar light emitting region for the light emitting unit 21, uniform linearly polarized light can be irradiated to the entire detection region R1, and the detectable detection region R1 can be expanded to simultaneously inspect the entire carton CT. In the inspection apparatus 1, as an example, a configuration using a surface emitting type white LED light is adopted.

[0037] The linearly polarized light plate 22 is a linearly polarized light plate having a polarization axis in an arbitrary one direction in the plane (in this example, in the X-Z plane). When the light emitted from the light emitting unit 21 passes through the linearly polarized light plate 22, the component vibrating in the direction parallel to the polarization axis is emitted in the emission direction L1, and the back surface of the packaged product PK is irradiated with linearly polarized light.

[0038] The imaging means 3 is an imaging unit that is arranged at a position facing the light irradiation unit 2 with the packaged product PK interposed therebetween in the emission direction L1 and captures an image of the packaged product PK from a direction opposite to the emission direction L1. In this example, the imaging means 3 is arranged on the front surface (positive Y-axis direction) side of the packaged product PK loaded on the conveying means TM, and adopts a configuration of capturing an image of the front surface, which is the outer surface of the packaged product PK on the side opposite to the imaging means 3.

[0039] As shown in FIGS. 1(a) and 2, the imaging means 3 includes a linearly polarized light plate 31 and an imaging element 33.

[0040] The linear polarizing plate 31 is arranged in front of the emission direction L1 (in the positive Y-axis direction) and is arranged parallel to the linear polarizing plate 22 in a cross-sectional view, and the directions of the polarization axes of the linear polarizing plate 22 and the linear polarizing plate 31 are different. For example, the polarization axis of the linear polarizing plate 31 may be arranged to be orthogonal to the polarization axis of the linear polarizing plate 22 in the plane (in the X-Z plane in this example). Therefore, the linearly polarized light vibrating in the direction parallel to the polarization axis of the linear polarizing plate 22, which is emitted from the light irradiation unit 2 in the emission direction L1, is blocked or suppressed from passing by the linear polarizing plate 31. And, among the scattered light generated after passing through the linear polarizing plate 22, only the component vibrating in the direction parallel to the polarization axis of the linear polarizing plate 31 passes through the linear polarizing plate 31 and reaches the imaging element 33.

[0041] The imaging element 33 is arranged in front of the emission direction L1 of the linear polarizing plate 31 (in the positive Y-axis direction) and images an image based on the linearly polarized light emitted through the linear polarizing plate 31. For the imaging element 33, for example, a camera using a CCD (Charge Coupled Device) image sensor may be used.

[0042] Furthermore, the imaging means 3 may include an optical member 32 such as a lens for condensing light (L2) onto the light receiving surface of the imaging element 33 between the linear polarizing plate 31 and the imaging element 33. In this example, the optical axis CL passing through the centers of the optical member 33 and the imaging element 33 is parallel to the emission direction L1 and is configured to pass through the center of the light emitting region of the light emitting unit 21.

[0043] The detection processing unit 4 is a processing unit that is electrically connected to the passage detection means PS and the imaging means 3, acquires an image from the imaging element 33 based on the passage timing of the packaged product PK, and performs a process of detecting film winding of the packaged product PK based on the image. The detection processing unit 4 is realized, for example, as a computer including a general CPU (Central Processing Unit), a RAM (Random Access Memory), and a program executed by these. The detection processing unit 4 reads a control program related to the detection process from a storage device or the like into the RAM and executes it, thereby realizing a function related to the detection process of film winding in the packaged product PK.

[0044] Specifically, the detection processing unit 4 detects, as an image portion indicating the film-wrapped portion of the package PK, an image captured by the imaging element 3 based on a component in a direction parallel to the polarization axis of the linear polarizing plate 31 that is generated by the wrapped portion of the translucent film after passing through the linear polarizing plate 22 among the linearly polarized light emitted from the light irradiation unit 2, thereby detecting film wrapping of the package PK. Details of the processing method will be described later.

[0045] Furthermore, the detection processing unit 4 may detect the orientation of the package PK by detecting the shape and / or orientation of the image portion on the front surface of the package PK. Details of the processing method in the detection processing unit 4 will be described later.

[0046] The illumination means 5 is illumination for irradiating light (L3) onto the front surface, which is the outer surface on the side opposite to the imaging means 3 of the package PK, from an angle different from that of the light irradiation unit 2. By providing the illumination means 5, the imaging means 3 acquires an image of the surface of the package PK on the side facing the imaging means 3 by the reflected light irradiated from the illumination means 5.

[0047] Thereby, the detection processing unit 4 specifies an image region corresponding to the package in the image of the package PK based on a clear image captured under the reflected light from the illumination means 5 with a different illumination angle with respect to the emission direction L1. At the same time, the detection processing unit 4 detects an image portion corresponding to the film-wrapped portion of the package PK based on an image including a high contrast captured based on the linearly polarized light irradiated from the rear of the package PK by the light irradiation unit 2. That is, according to the apparatus 1, in addition to the linearly polarized light irradiated from the rear of the package PK by the light irradiation unit 2, by effectively utilizing the reflected light irradiated from an angle different from that of the light irradiation unit 2, the film wrapping of the package PK can be detected with higher accuracy.

[0048] <Operation of the inspection apparatus 1> Hereinafter, the operation of the inspection apparatus 1 having the above configuration will be described. FIG. 3 is a flowchart showing an outline of the detection processing operation in the inspection apparatus 1. FIGS. 4(a) and 4(b) are diagrams for explaining an outline of image acquisition in the inspection apparatus 1.

[0049] First, as shown in FIG. 3, in the inspection apparatus 1, the detection processing unit 4 acquires an image of a detection target area R1 including the packaged product PK conveyed by the conveying means TM from the imaging means 3 with the light irradiation unit 2 being irradiated (step S1).

[0050] In the inspection apparatus 1, by detecting an image portion of the film that is wrinkled on the outer surface of the packaged product PK facing the surrounding space and parallel to the emission direction L1 among the outer surfaces of the packaged product PK, film wrinkling on the outer surface of the packaged product PK is detected.

[0051] As shown in FIG. 4(a), when the packaged product PK is in a shape where the single - layer cartons CT(1) to (5) are arranged side by side on the conveying means TM, the imaging means 3 is set to acquire images of the detection target areas R1(1) to (5) divided corresponding to the cartons CT(1) to (5). Similarly, when the double - stacked cartons CT(1) to (5) are arranged side by side on the conveying means TM, as shown in FIG. 4(b), the imaging means 3 is set to acquire images of the detection target areas R1(1) to (5). The detection processing unit 4 calculates the time when the cartons CT(1) to (5) pass through the detection target areas R1(1) to (5) based on a signal from the passage detection means PS, and acquires an image of the detection target areas R1(1) to (5) at that time from the imaging means 3.

[0052] Next, for each image of the detection target areas R1(1) to (5), a package image area RP is specified (step S2). FIG. 5 is a schematic diagram of an image corresponding to the detection target area R1(1) imaged by the imaging means 3. As shown in FIG. 5, the shape and / or orientation of an image portion PRI such as a front printed display in the image PKI of the packaged product PK is detected, for example, by pattern matching or the like, to specify the package image area RP in the image PKI of the packaged product PK.

[0053] At this time, the surface of the packaging product PK facing the imaging means 3 is irradiated (L3) by the reflected light emitted from the illumination means 5, so that the imaging means 3 can always acquire a clear image even in, for example, a dark environment. As a result, the detection processing unit 4 can accurately identify the package image area RP in the package product image PKI based on the clear images of the detection areas R1(1) to (5) imaged under the reflected light.

[0054] Next, an adjacent image area with respect to the package image area RP is set (step S3). At this time, as shown in FIG. 5, when the detection area is the detection area R1(1) located at the end of the package PK in the X direction, the adjacent image areas RA are set in front of and above the package image area RP. Similarly, the same applies to the case of the detection area R1(5) located at the end of the package PK in the X direction. On the other hand, when the detection area is the detection areas R1(2) to (4) located inside the package PK in the X direction, the adjacent image area RA above the package image area RP is set.

[0055] Next, for each image of the detection areas R1(1) to (5), the image elements included in the set adjacent image area RA are detected (step S4). Specifically, it is detected whether there is an area having a predetermined area or more and a predetermined luminance or more in the adjacent image area RA. If it exists, it is detected as an image portion indicating the film portion curled from the packaging product PK assuming that there is a high-luminance image area RH of the package PK. And in this case, it is determined as a packaging defect due to film curling, which is one aspect of the packaging defect in the packaging product PK.

[0056] In this way, when there is a portion of the light-transmissive film curled adjacent to the packaging product PK, the linearly polarized light emitted from the light irradiation unit 2 has its polarization disrupted and the light is scattered by the curled portion of the light-transmissive film. As a result, the component in the direction parallel to the polarization axis of the linear polarizing plate 31 passes through the linear polarizing plate 31 and is imaged as an image by the imaging means 3.

[0057] Next, based on the detection results of the shape and / or orientation of the image portion PRI such as the front printed display in the image PKI of the packaged product PK in step S3, for each image of the inspection regions R1(1) to (5), the correctness of the shape and / or orientation of the packaged product PK is determined (step S4). If it is not normal, it is determined that there is a packaging defect due to the packaged product PK being toppled or having the wrong orientation, and the process ends.

[0058] Here too, since the surface of the packaged product PK facing the imaging means 3 is illuminated (L3) by the reflected light emitted from the illumination means 5, the imaging means 3 can always acquire a clear image. As a result, the detection processing unit 4 can determine the correctness of the shape and / or orientation of the packaged product PK with high accuracy based on the clear image captured under the reflected light.

[0059] <Evaluation Test> Hereinafter, an evaluation test for film curl detection was conducted using a non-defective sample without film curl and a defective packaged product sample with film curl by the inspection apparatus 1 according to the embodiment. The results will be described below.

[0060] (Test Results) FIG. 6 is a schematic diagram showing the result of the evaluation test by the film packaged product inspection apparatus 1 and an image of a non-defective product without film curl as an inspection target. FIGS. 7 and 8 are schematic diagrams showing the results of the evaluation test by the film packaged product inspection apparatus 1 and images of defective packaged products with film curl as inspection targets. FIG. 7 shows the case where the film packaged products are arranged in a single row in a carton, and FIG. 8 is a schematic diagram of an image in the case where the film packaged products are arranged in two rows in a carton.

[0061] When the inspection target is a non-defective product without film curling, as shown in Fig. 6, it can be seen that there is no high-brightness image area RH in the adjacent image area RA around the package image area RP in the image acquired by the inspection device 1. That is, when the inspection target is a non-defective product without film curling, the linearly polarized light emitted in the emission direction L1 from the light irradiation unit 2 is blocked or suppressed from passing by the linear polarizing plate 31, and no light reaches the imaging means 3. Therefore, the image is displayed in black in the adjacent image area RA.

[0062] On the other hand, when there is film curling in the inspection target, as shown in Figs. 7 and 8, it can be seen that a high-brightness image area RH is clearly displayed in white in the black image of the adjacent image area RA on the side of the package image area RP in the acquired image. That is, when there is film curling in the inspection target, the linearly polarized light emitted from the light irradiation unit 2 has its polarization disrupted and the light is scattered by the curled part of the translucent film. As a result, the component in the direction parallel to the polarization axis of the linear polarizing plate 31 that is generated passes through the linear polarizing plate 31 and is imaged by the imaging means 3, and is clearly displayed in white as a high-brightness image area RH in the black image in the adjacent image area RA where no light reaches in the case of non-defective products. Based on this high contrast with the surrounding area, the detection processing unit 4 can detect the image part with film curling in the adjacent image area RA with higher accuracy.

[0063] From the above results, it was confirmed that according to the inspection device 1, the detection of film curling in the package PK in which the object to be packaged is packaged with a translucent film can be stably performed with high accuracy.

[0064] <Summary> As described above, the inspection apparatus 1 includes a light irradiation unit 2 that has a first linear polarizing plate 22, emits linearly polarized light through the first linear polarizing plate 22, and irradiates the linearly polarized light onto the packaged product PK; an imaging unit 3 that is disposed at a position facing the light irradiation unit 2 with the packaged product PK sandwiched therebetween in the emission direction L1 of the light irradiation unit 2, has a linear polarizing plate 31 that blocks or suppresses the passage of linearly polarized light, and captures an image of the film-packaged PK product through the second linear polarizing plate 31; and a detection processing unit 4 that detects film curling of the film-packaged product by detecting an image portion of the curled film of the packaged product PK in the image. Further, the linear polarizing plate 31 may be configured such that the polarization axis and the direction of the polarization axis of the linear polarizing plate 22 are different in a plane parallel to the linear polarizing plate 22.

[0065] As described above, in the inspection of packaging defects of film-packaged products, in the detection of film curling where the translucent film curls from the object to be packaged, since the curled film portion is present away from the surface of the object to be packaged, in the conventional inspection methods using a light sensor that is local and has a low margin for detection, or an inspection method using imaging with reflected light, it is difficult to stably perform the inspection, and a method capable of inspecting film curling with high accuracy has been demanded.

[0066] On the other hand, according to the inspection apparatus 1, with the above-described configuration, among the linearly polarized light emitted from the light irradiation unit 2, after passing through the linear polarizing plate 22, the linearly polarized light is disrupted by the curled portion of the translucent film, and an image captured by the imaging element 33 based on the component in the direction parallel to the polarization axis of the linear polarizing plate 31 generated by the scattering of light can be detected with high accuracy as an image portion indicating the film portion curled from the packaged product PK based on a high contrast with the surroundings. As a result, film curling in the packaged product PK can be stably detected with high accuracy.

[0067] Further, by using a light emitting device having a planar light emitting region for the light emitting unit 21, it is possible to irradiate the entire inspection region R1 with uniform linearly polarized light and expand the detectable inspection region R1 to simultaneously inspect the entire carton CT.

[0068] In the inspection device 1, the packaged product PK has a rectangular parallelepiped shape, and the detection processing unit 4 may be configured to detect film curling of the packaged product PK by detecting an image portion of the curled film on the outer surface of the packaged product PK that faces the surrounding space and is parallel to the emission direction L1.

[0069] With such a configuration, by detecting an image portion of the curled film on the outer surface of the packaged product PK that faces the surrounding space and is parallel to the emission direction L1 among the outer surfaces of the packaged product PK, film curling on the outer surface of the packaged product PK can be detected.

[0070] Further, the detection processing unit 4 may be configured to detect a package image region RP and an adjacent image region RA adjacent thereto based on the image, and detect a region having a predetermined luminance or more and a predetermined area or more in the adjacent image region RA as an image portion of the curled film of the packaged product PK.

[0071] With such a configuration, an image portion of the curled film on the outer surface of the packaged product PK parallel to the emission direction L1 can be specifically detected.

[0072] In the inspection device 1, the detection processing unit 4 may be configured to detect the orientation of the packaged product PK by detecting the shape and / or orientation of an image portion of the outer surface of the packaged product PK on the side opposite to the imaging means 3.

[0073] With such a configuration, when the shape and / or orientation of the packaged product PK is not regular, it can be determined that there is a packaging defect due to the packaged product PK falling over or being in the wrong direction.

[0074] Further, the inspection device 1 may further include an illumination means 5 that irradiates light (L3) onto the outer surface of the packaged product PK on the side opposite to the imaging means 3 from an angle different from the emission direction L1, and the imaging means 3 may be configured to acquire an image PKI of the packaged product PK by the reflected light from the illumination means 5.

[0075] With such a configuration, the detection processing unit 4 identifies the package image area RP based on a clear image PKI of the packaged product PK captured under the reflected light from the illumination means 5 with different illumination angles with respect to the emission direction L1, and also, based on an image including a high contrast captured based on the linearly polarized light irradiated from behind the packaged product PK by the light irradiation unit 2, can detect an image portion RH corresponding to the film portion curled from the packaged product PK. Thereby, it is possible to perform a process of detecting film curling of the packaged product PK with higher accuracy.

[0076] ≪Modification Example≫ Although the film packaged product inspection apparatus and the film packaged product inspection method according to the embodiment have been described, the present disclosure is not limited to the above embodiments except for its essential characteristic components. For example, forms obtained by applying various modifications conceivable by those skilled in the art to the embodiment, and forms realized by arbitrarily combining the components and functions in each embodiment without departing from the spirit of the present invention are also included in the present disclosure. Hereinafter, a modification example will be described as an example of such a form.

[0077] (1) In the inspection apparatus 1 according to the embodiment, a configuration using a surface-emitting type white LED light for the light emitting unit 21 in the light irradiation unit 2 was shown. However, the light emitting unit 21 may use other light emitting devices, and light other than white light may also be used.

[0078] (2) In the inspection apparatus 1 according to the embodiment, the light irradiation unit 2 is configured to irradiate light in the horizontal direction toward the packaged product PK loaded on the conveying means TM. However, in the inspection apparatus 1, as long as it is configured to detect film curling on the outer surface of the packaged product PK that faces the surrounding space and is parallel to the light irradiation direction according to the inspection apparatus 1, the direction in which the light irradiation unit 2 irradiates light toward the packaged product PK is not limited to the above. For example, by arranging the light irradiation unit 2 and the imaging means 3 across the conveying means TM composed of a translucent member and irradiating light in the vertical direction for detection, film curling of the packaged product PK on the front and back surfaces of the packaged product PK may be detected.

[0079] (3) One aspect of the present disclosure is not limited to the above-described embodiments, and the following cases are also included in one aspect of the present disclosure. For example, one aspect of the present disclosure also includes a case where all or part of the control unit of the film packaging product inspection apparatus is configured by a computer system including a recording medium such as a microprocessor, ROM, RAM, a hard disk unit, and the like. When the microprocessor operates according to the computer program, the control method of each film packaging product inspection apparatus achieves its function. Further, part or all of the functions of the control method of the film packaging product inspection apparatus may be realized by a processor such as a CPU executing a program.

[0080] Also, the order in which the above steps are executed is for illustrative purposes to specifically describe the present invention, and other orders may be possible. Also, part of the above steps may be executed simultaneously (in parallel) with other steps.

[0081] ≪Supplementary Explanation≫ All of the embodiments described above show preferred specific examples of the present invention. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, processes, order of processes, etc. shown in the embodiments are examples and are not intended to limit the present invention. Also, among the components in the embodiments, those not described in the independent claims indicating the highest-level concept of the present invention are described as optional components constituting a more preferred form.

[0082] Also, the order in which the above method is executed is for illustrative purposes to specifically describe the present invention, and other orders may be possible. Also, part of the above method may be executed simultaneously (in parallel) with other methods.

[0083] Also, for ease of understanding of the invention, the scales of the components in each of the figures cited in the above embodiments may be different from the actual ones. Also, the present invention is not limited by the descriptions of the above embodiments and can be appropriately changed without departing from the gist of the present invention. Furthermore, at least a part of the functions of each embodiment and its modifications may be combined.

Industrial Applicability

[0084] The film package inspection apparatus and the film package inspection method according to one aspect of the present disclosure can be suitably used as inspection means for a film package in which a package object such as a carton containing an article is wrapped with a translucent film and carried out from a factory production line, a logistics warehouse, or the like.

Description of Symbols

[0085] 1 Film package inspection apparatus 2 Light irradiation means 21 Light emitting part 22 Linear polarizing plate (first linear polarizing plate) 3 Imaging means 31 Linear polarizing plate (second linear polarizing plate) 32 Optical member 33 Image sensor 4 Detection processing unit 5 Illumination means PK Film package CT Carton TM Conveying means RI(1)~(5) Inspection area PKI Image of the package PRI Image part such as printed display RP Package image area RA Adjacent image area RH High-brightness image area

Claims

1. A film package inspection apparatus for detecting film curling of a film package in which an article is packaged with a translucent film, comprising: a light irradiation unit having a first linear polarizer, emitting linearly polarized light through the first linear polarizer, and irradiating the linearly polarized light onto the film package; an imaging means disposed at a position opposite to the light irradiation unit across the film package in the emission direction of the light irradiation unit, having a second linear polarizer that suppresses the passage of the linearly polarized light, and imaging an image of the film package through the second linear polarizer; a detection processing unit that detects film curling of the film package by detecting an image portion of the curled film of the film package in the image; and a film package inspection apparatus.

2. Based on the image, the detection processing unit detects a package image region and an adjacent image region adjacent to the package image region, and detects, as an image portion of the curled film of the film package, a region in the adjacent image region having a luminance equal to or higher than a predetermined luminance and an area equal to or larger than a predetermined area. The film package inspection apparatus according to claim 1.

3. The detection processing unit detects film curling on the outer surface of the film package by detecting an image portion of the curled film on the outer surface of the film package facing the surrounding space and parallel to the emission direction. The film package inspection apparatus according to claim 1.

4. The detection processing unit detects the orientation of the film package by detecting the shape and / or orientation of an image portion of the outer surface of the film package on the side opposite to the imaging means. The film package inspection apparatus according to claim 3.

5. Furthermore, it includes an illumination means for irradiating light onto the outer surface of the side of the film package opposite to the imaging means from an angle different from the emission direction, and the imaging means images the film package by reflected light from the illumination means. The film package inspection apparatus according to claim 3.

6. A film package inspection method for detecting film curling of a film package in which an article is packaged with a translucent film, comprising: a step of emitting linearly polarized light through a first linear polarizer and irradiating the linearly polarized light onto the film package; A step of imaging an image of the film-wrapped product through a second linear polarizing plate that suppresses the passage of the linearly polarized light from a position facing the light irradiation unit across the film-wrapped product in the emission direction of the light irradiation unit; A step of detecting film curling of the film-wrapped product by detecting an image portion of the curled film of the film-wrapped product in the image; having A film-wrapped product inspection method.

7. In the detecting step, by detecting an image portion of the curled film on the outer surface of the film-wrapped product that faces the surrounding space and is parallel to the emission direction, film curling on the outer surface of the film-wrapped product is detected The film-wrapped product inspection method according to claim 6.

8. In the detecting step, based on the image, a package image region and an adjacent image region adjacent to the package image region are detected, A region having a luminance equal to or higher than a predetermined luminance and an area equal to or larger than a predetermined area in the adjacent image region is detected as an image portion of the curled film of the film-wrapped product The film-wrapped product inspection method according to claim 6.

Images