JP6357362B2 - Container mouth inspection device and inspection method - Google Patents

Description

  The present invention relates to an inspection apparatus and an inspection method for inspecting a mouth portion of a container.

  In order to inspect whether the mouth portion of the container is formed in a regular shape or is free of defects such as a chip, a method is known in which an image of the mouth portion is captured by a camera and the image is processed (the following patents). Reference 1). In such a conventional inspection method, it is possible to perform an inspection process for finding defects or irregularities in the screw or top surface of the container mouth in a transport process in which a plurality of containers are continuously transported by a transport means such as a conveyor. This enables efficient and highly accurate inspection. An inspection apparatus for executing such an inspection method includes an illumination unit that irradiates light to the mouth of the container, a camera that images the mouth of the container from above, and an arithmetic process that performs image processing on an image captured by the camera. Means are provided.

Japanese Patent No. 4986255

  As a form of the mouth portion of the container, there is one in which a screw is provided on the outer periphery of the mouth portion and an annular bead is provided below the screw. In the mouth portion of such a container, the bead has a larger outer diameter than the outer diameter of the thread. When inspecting the container mouth part of this form by the above-described conventional method, the bead appears in the image of the container mouth imaged from above the container by the camera, and the bead appears outside the outer edge of the screw. There arises a problem that an image of a certain screw or top surface cannot be clearly captured.

  In particular, in some glass bottles, the beginning of threading of the mouth stands 90 ° from the outer periphery when viewed from above, and the mouth of such a bottle is prone to chipping at the beginning of threading. Although an inspection is performed with an image viewed from above the bottle, since the beginning of threading overlaps with the bead under the screw and appears, there is a problem that the chipping cannot be clearly determined.

  This invention makes it an example of a subject to cope with such a problem. That is, the object of the present invention is to enable high-accuracy inspection by clearly capturing images of the container mouth screw and the top surface for the container mouth portion having a bead below the screw. It is.

  In order to achieve such an object, the present invention includes the following configurations among several inventions described in the specification.

An inspection device comprising an illuminating means for irradiating light to a container mouth and a camera for imaging the container mouth from above, and inspecting the container mouth by an image taken by the camera, wherein the camera is located under the container mouth An imaging optical system capable of performing close-up imaging in which the outer bead is hidden by the outer peripheral edge of the container mouth , and the imaging optical system connects the upper outer periphery of the bead and the outer peripheral edge of the screw in the container mouth. A container mouth portion inspection apparatus having an angle of view larger than an angle formed by a pair of symmetrical lines with respect to a central axis of the portion.

An inspection method in which a container mouth is imaged from above with a camera, and the container mouth is inspected by an image captured by the camera, such that the bead below the container mouth is hidden by the outer periphery of the container mouth by the camera. the proximity imaging have rows, the imaging optical system of the camera, angle larger than that formed by symmetrical pair of lines to a central axis of the container mouth portion connecting the outer periphery of the screw in the upper end outer peripheral edge and the container mouth portion of said bead A container mouth inspection method characterized by having an angle of view .

  In the present invention having such a feature, since the bead is concealed by the outer peripheral edge of the container mouth portion with respect to the container mouth portion having a bead provided below the screw, the screw of the container mouth portion can be performed. High-precision inspection can be realized by clearly capturing images on the top and top.

It is explanatory drawing which showed the structural example of the container opening part test | inspection apparatus which concerns on one Embodiment of this invention. It is explanatory drawing which shows the principal part of the container opening part inspection apparatus which concerns on embodiment of this invention, (a) has shown embodiment of this invention, (b) has shown the prior art example. The image of the container mouth part imaged by the container mouth part inspection apparatus which concerns on embodiment of this invention is shown, (a) shows the image imaged by the container mouth part inspection apparatus which concerns on embodiment of this invention (B) shows an image captured by a conventional container mouth inspection device. It is explanatory drawing which showed the example of installation of the imaging optical system in the container opening part inspection apparatus which concerns on embodiment of this invention ((a), (b) is the side view seen from two orthogonal directions).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing a configuration example of a container mouth portion inspection apparatus according to an embodiment of the present invention. The container mouth inspection device 1 includes an illumination unit 2, a camera 3, and an inspection unit 4.

  The illumination means 2 irradiates light to the container mouth part M, and scatters the light emitted from the light source part 2A and the light source part 2A disposed on the container mouth part M along the outer periphery of the container mouth part M. A scattering plate is provided. The center of the light source part 2A arranged in an annular shape is arranged coaxially with the central axis O of the container mouth part M, so that the entire circumference of the container mouth part M is illuminated uniformly.

  The camera 3 images the container mouth M from above, and its optical axis is arranged coaxially with the central axis O of the container mouth M. The camera 3 includes an imaging optical system 30 that forms an image of a planar image of the container mouth M on an imaging surface of an imaging element (not shown) and an imaging device 31 that incorporates the imaging element described above.

  The inspection unit 4 receives an image signal picked up by the camera 3 and inspects the thread defect of the container mouth M by performing image processing on the image signal. For example, the inspection unit 4 includes an arithmetic processing unit such as a PC. be able to. Here, the container mouth portion M to be inspected is provided with a bead M1 below, and a screw M2 is provided on the upper outer periphery of the bead M1. In particular, it is effective for inspecting the mouth of a bottle where the threading start point as viewed from above stands close to 90 °.

  FIG. 2 is an explanatory view showing the main part of the container mouth inspection apparatus according to the embodiment of the present invention, wherein (a) shows an embodiment of the present invention and (b) shows a conventional example. . As shown in FIG. 2A, the camera 3 of the container mouth inspection apparatus 1 according to the embodiment of the present invention can perform close-up imaging in which the bead M1 below the container mouth M is hidden by the outer periphery of the container mouth M. An imaging optical system 30 is provided. More specifically, the imaging optical system 30 includes a pair of lines S1 and S1 that are symmetrical with respect to the central axis O of the container mouth M that connects the upper outer periphery P1 of the bead M1 and the outer periphery P2 of the screw M2 in the container mouth M. Has an angle of view larger than the angle formed by. The imaging optical system 30 can be configured by a wide-angle lens having a relatively short focal length.

  Fig.3 (a) has shown the image which imaged the container mouth part M from the top with the camera 3 in embodiment of this invention. The bead M1 is not shown outside the screw M2. By obtaining such an image, the top surface of the container mouth M and the outer edge of the screw M2 can be clearly imaged.

  In contrast, FIG. 2B shows a camera 3J of a conventional container mouth portion inspection device. This camera 3J uses an imaging optical system 30J having a long focal length and a narrow angle of view compared to the imaging optical system 30 applied to the camera 3 of the container mouth inspection device 1 according to the embodiment of the present invention. . When the container mouth M is imaged from above with such a camera 3J, an image in which the bead M1 is captured outside the screw M2 is captured as shown in FIG. 3B. According to such an image, the outer edge of the screw M2 overlaps with the bead M1, and it is difficult to clearly grasp the outer edge of the screw M2 to be inspected.

  FIG. 4 is an explanatory view showing an installation example of an imaging optical system in the container mouth inspection apparatus according to the embodiment of the present invention ((a) and (b) are side views as seen from two orthogonal directions. ). Here, the imaging device 31 includes a solid-state imaging device (CCD) 31A having a length of 3.6 mm and a width of 4.8 mm, and a camera 3 including an imaging optical system 30 including a wide-angle lens having a focal length of 4 mm. The distance from the imaging surface of the element 31A to the top surface of the container mouth M is 73.5 mm, the distance from the rear end of the imaging optical system 30 to the top surface of the container mouth M is 56 mm, and the mouth outer diameter is 24.5 mm. An image of the container mouth M having a bead outer diameter of 31 mm and a distance of 11 mm from the top surface where the screw M2 is formed to the bead M1 was taken.

  The vertical angle of view shown in FIG. 4 (a) is 28 ° because the image width at the top surface position of the container mouth M is 33.2 mm, and the horizontal angle shown in FIG. 4 (b). The angle of view in the direction was 37 ° because the image width at the top position of the container mouth M was 44.3 mm. When the container mouth M was imaged in close proximity at such an angle of view, the bead M1 was hidden by the outer peripheral edge of the container mouth M, and an image that clearly captured the image of the screw M2 and the top surface could be obtained.

  According to the container mouth portion inspection apparatus and the container mouth portion inspection method using the same according to the embodiment of the present invention having such a feature, the bead M1 below the container mouth portion M is moved by the camera 3 to the outer peripheral edge of the container mouth portion M. By performing close-up imaging so as to be hidden, the image of the screw M2 of the container mouth M and the top surface can be clearly captured, and a highly accurate inspection can be realized.

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and the design can be changed without departing from the scope of the present invention. Is included in the present invention. In addition, the above-described embodiments can be combined by utilizing each other's technology as long as there is no particular contradiction or problem in the purpose and configuration.

1: container mouth inspection device, 2: illumination means, 2A: light source unit, 3: camera,
4: inspection unit, 30: imaging optical system, 31: imaging device, 31A: solid-state imaging device,
M: Container mouth, M1: Bead, M2: Screw, O: Center axis

Claims (2)

An inspection device comprising an illumination means for irradiating light to a container mouth and a camera for imaging the container mouth from above, and inspecting the container mouth by an image captured by the camera,
The camera includes an imaging optical system capable of proximity imaging in which a bead below the container mouth is hidden by the outer periphery of the container mouth ,
The imaging optical system has an angle of view larger than an angle formed by a pair of symmetrical lines with respect to a central axis of the container mouth part connecting an outer peripheral edge of an upper end of the bead and an outer peripheral edge of a screw in the container mouth part. Container mouth inspection device. An inspection method in which a container mouth is imaged with a camera from above, and the container mouth is inspected with an image captured by the camera,
Bead of the container mouth subordinate side by the camera have line closer to the camera so as to be hidden by the outer peripheral edge of the container opening,
The imaging optical system of the camera has an angle of view larger than an angle formed by a pair of symmetrical lines with a central axis of the container mouth portion connecting the outer periphery of the upper end of the bead and the outer periphery of the screw in the container mouth portion. container mouth portion inspection method characterized by there.

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