JPH1062359A - Method and device for inspecting defect - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly detect a defect present in a glass bottle mouth part by rotating a translucent vessel to be inspected around the axial line, emitting an illuminating light from just above to provide a reflected image from the obliquely upper part, and judging the presence of the defect on the basis of the reflected image. SOLUTION: This inspecting device has a bottle rotating device for rotating a glass bottle W around its axial line Cw . The projecting surface 13 of a light source 14 above the glass bottle W is set concentrically with the axial line of the glass bottle W. An image pickup camera 15 for taking the image of the mouth part WO of the glass bottle W is arranged obliquely above the glass bottle W. The reflected image of the mouth part WO taken by the image pickup camera 15 is read into an image processing device 16, and the presence of a hair crack is judged by a defect judging device 170. The reflected image of the mouth part WO taken by the image pickup camera 15 is shown as a bright part Ip . In case of a hair crack laid along the circumferential direction of the mouth part WO, a random unstable bright part Iu by the hair crack WC is generated in the reflected light from the light source 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defect inspection method and apparatus for optically and efficiently inspecting a light-transparent bottle for damage along a longitudinal or circumferential direction.

[0002]

2. Description of the Related Art In glass bottles for storing alcoholic beverages such as beer, or liquid seasonings such as soy sauce, especially in the mouth portion sealed with a crown or the like, there is a possibility that defects such as chipping or cracking may occur due to opening of the bottle. Is very high. For this reason,
When reusing such a glass bottle, it is necessary to inspect the mouth for any defects such as chipping or cracks.

Usually, when such a glass bottle is inspected for defects, not only is the reliability of the inspection result extremely high, but also a large number of glass bottles must be automatically processed. Must be completed in an extremely short time, specifically, about 300 to 500 milliseconds.

In recent years, cracks formed in the mouth of a glass bottle,
That is, hair cracks are problematic due to the difficulty of detection, and as a defect inspection apparatus for such hair cracks, for example, besides JP-A-62-69154 and JP-A-2-257044, JP-A-3-1
No. 35376 is well known.

A bottle defect inspection apparatus disclosed in Japanese Patent Application Laid-Open No. 62-69154 illuminates a bottle illuminator with a circular illuminator from directly above a bottle jar, and uses an imaging device arranged above the center of the ring illuminator to perform bottle illuminating. Hair cracks along the circumferential direction of the mouth are detected by image processing.

A bottle inspection apparatus disclosed in Japanese Patent Application Laid-Open No. 2-257044 projects illumination light from a pair of light sources to a bottle screw portion from obliquely above the bottle screw portion. The hair crack along the circumferential direction of the portion is detected by image processing using a television camera via a light-shielding reflector.

Further, Japanese Patent Application Laid-Open No. 3-135376 discloses that an illumination light from a light source is obliquely projected onto a mouth portion of a glass bottle, and transmitted light refracted at the mouth portion is transmitted through the mouth portion. The image is observed with a monitor camera, and the presence or absence of a hair crack at the mouth along the longitudinal direction of the glass bottle is determined using an image processing device.

[0008]

SUMMARY OF THE INVENTION Japanese Patent Application Laid-Open No. 62-6915
In the bottle defect inspection apparatus disclosed in Japanese Patent Application Publication No. 4 (1999) -1995, the image incident on the imaging device has an annular bright portion corresponding to the bottle portion in the center of the visual field, so that the hair crack is buried in this bright portion. Thus, there is a possibility that a small hair crack cannot be detected.

[0009] Further, a hair crack present in the inside of a bottle that becomes a blind spot or in a constricted portion cannot be detected from the imaging device located above the center. Furthermore, since both the light source and the imaging device are arranged above the bottle, it is difficult to detect the arc rack along the vertical direction due to the angle of reflection of light.

Further, the bottle inspection apparatus disclosed in Japanese Patent Application Laid-Open No. 2-257044 has a drawback that the equipment cost increases because it is necessary to prepare a pair of light sources and use a light-shielding reflector. Furthermore, since the bright portion of the bottle screw portion is shielded by using the light-shielding reflector, the detection region of the hair crack is substantially narrowed, and the inspection time is prolonged. In addition, the amount of light applied to the bottle changes depending on the positional relationship between the pair of light sources and the bottle, so that the amount of light reflected from the hair crack also changes. Therefore, depending on the combination of the rotation position of the arc rack and the amount of reflected light, the arc rack may not be detected. Further, since both the light source and the imaging device are arranged above the bottle, it is difficult to detect the arc rack along the vertical direction from the relationship of the light reflection angle.

On the other hand, in the apparatus disclosed in Japanese Patent Application Laid-Open No. 3-135376, the relative positional relationship for reflected light from a hair crack existing at the mouth of a glass bottle to enter a monitor camera is limited. Therefore, it is difficult to rotate the glass bottle at a high speed for inspection, and a lot of time is required for the processing. For this reason, the inspection time for each glass bottle is prolonged, and it is not very practical as a glass bottle defect inspection apparatus that requires high-speed and large-volume processing. In addition, since the image incident on the image processing apparatus is transmitted light from a glass bottle, the entire field of view is too bright, and as in the bottle defect inspection apparatus disclosed in Japanese Patent Application Laid-Open No. 62-69154, the image is minute. There is a possibility that it may be difficult to detect an unusual hair crack.
In addition, the positional relationship between the light source, the bottle, and the imaging device is such that the vertical arc rack is arranged so that the amount of reflected light is best reflected toward the imaging device. The amount of reflected light from the hair crack along the circumferential direction hardly reaches the imaging device, and it is difficult to detect the hair crack along the circumferential direction of the mouth.

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a defect inspection method and apparatus capable of quickly and reliably detecting the presence or absence of a hair crack in a mouth portion of a glass bottle at low cost.

[0013]

According to a first aspect of the present invention, there is provided:
Rotating the light-transmissive container to be inspected around its axis; projecting illumination light onto the container to be inspected from directly above the container to be inspected; and rotating the container to be inspected from obliquely above the container to be inspected. And a step of judging the presence or absence of a defect in the container to be inspected based on the reflection image of the container to be inspected.

According to a second aspect of the present invention, there is provided a light source which is positioned above a light-transmissive container to be inspected carried into an inspection area and projects illumination light downward onto the container to be inspected; An imaging optical system arranged obliquely above the inspection container to obtain a reflection image of the container to be inspected, container rotation means for rotating the container to be inspected one or more rotations around the axis thereof in the inspection region, and the imaging optical system And a determining means for detecting the presence or absence of a defect in the container to be inspected based on a reflected image from the inspection container.

According to the present invention, the container to be inspected carried into the inspection area is rotated around its axis by the container rotating means. The inspection container is irradiated with illumination light from a light source directly below, and a reflected image thereof is captured by an imaging optical system.
Based on the reflection image obtained by the imaging optical system, the determination means detects the presence or absence of a defect in the container to be inspected. The reflection image is in a state where the reflected light of the container to be inspected floats in a predetermined region in a dark visual field. When there is a defect in the container to be inspected, the reflected light floats out of the predetermined area in addition to the reflected light floating in the predetermined area.

On the other hand, according to a third aspect of the present invention, a step of rotating a light-transmitting container to be inspected around its axis and a step of projecting illumination light onto the container to be inspected from obliquely below the container to be inspected. Obtaining a reflection image of the container to be inspected from obliquely above the container to be inspected, and determining the presence or absence of a defect in the container to be inspected based on the reflection image of the container to be inspected. The feature lies in the defect inspection method.

According to a fourth aspect of the present invention, there is provided a light source positioned obliquely below a light-transmitting container to be inspected carried into an inspection area and projecting illumination light obliquely upward onto the container to be inspected; An imaging optical system arranged obliquely above the container to be inspected to obtain a reflection image of the container to be inspected, container rotating means for rotating the container to be inspected one or more rotations around its axis in the inspection area, and A defect inspection apparatus comprising: a determination unit configured to detect the presence or absence of a defect in the container to be inspected based on a reflection image from an optical system.

According to the present invention, the container to be inspected carried into the inspection area is rotated around its axis by the container rotating means. The container to be inspected is irradiated with illumination light from a light source obliquely upward, and a reflected image thereof is captured by an imaging optical system. Based on the reflection image obtained by the imaging optical system, the determination means detects the presence or absence of a defect in the container to be inspected. The reflection image is in a state where the reflected light of the container to be inspected floats in a predetermined region in a dark visual field. When there is a defect in the container to be inspected, the reflected light floats out of the predetermined area in addition to the reflected light floating in the predetermined area.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a defect inspection method according to a first embodiment of the present invention, illumination light is projected from a light source having an annular light projection surface coaxial with an axis of a container to be inspected. Alternatively, the defect of the container to be inspected may be a hair crack generated along the circumferential direction of the mouth.

In the defect inspection apparatus according to the second aspect of the present invention, the light source may have a light projection surface formed in an annular shape coaxial with the axis of the container to be inspected.

In the defect inspection method according to the third aspect of the present invention, it is preferable that the axis of the container to be inspected, the axis of the illumination light, and the axis in the observation direction for obtaining a reflected image are on the same plane. The defect of the container to be inspected may be a hair crack generated at the mouth along the axis.

In the defect inspection apparatus according to the fourth aspect of the present invention, it is desirable that the axis of the container to be inspected, the axis of the illumination light, and the axis of the imaging optical system are on the same plane.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the defect inspection apparatus according to the present invention capable of realizing the defect inspection method according to the present invention is applied to the inspection of a hair crack generated along the circumferential direction at the mouth of a glass bottle is shown in FIGS. This will be described in detail with reference to FIG.

As shown in FIG. 1 showing a schematic configuration of the present embodiment and FIG. 2 showing a plan configuration thereof, on the outer peripheral side of a turning table 11 which is turned intermittently by a driving device (not shown), a barrel of a glass bottle W is provided. part W semicircular notches 12 corresponding to _B are formed at equal intervals. This turn table 11 is set and the unloading position (not shown) with the load position (not shown) of the glass bottle W and the inspection position P _C, the glass bottle W before inspecting the notches 12 in the loading position (not shown) carried is carried by the conveyor through the inspection position P _C, the glass bottle W of tested held in the notches 12 in the unloading position is carried out by the carry-out conveyor (not shown). A guide member (not shown) is provided on the outer peripheral side of the turntable 11 from the carry-in position to the carry-out position, facing the outer periphery of the turntable 11 with a predetermined gap therebetween. , it is intermittently conveyed to the unloading position via the test position P _C from the loading position in a sandwich state between the out portion 12 cut with the guide member.

[0025] wherein the test position P _C, bottle rotating device (not shown) for rotationally driving the glass bottle W in the axial C _W around is provided, the glass bottle W in the inspection position P _C
Is rotated one or more revolutions around its axis C _W.

[0026] Above the glass bottle W in the inspection position P _C, is arranged a light source 14 having an annular light projection surface 13, the light projection surface 13 of the light source 14, the axis C _W of the glass bottle W And are set coaxially. In addition, inspection position P _C
An obliquely upper portion of the glass bottle W is provided with an imaging camera 15 for imaging the mouth W _O of the glass bottle W, and a reflected image of the mouth W _O captured by the imaging camera 15 is subjected to image processing. Read into the device 16 and the defect determination device 17
The presence / absence of a hair crack is determined.

As shown in FIG. 3, which schematically shows an example of the above-mentioned reflection image, the reflection image of the mouth W _O captured by the imaging camera 15 is a pair of arc-shaped mouths W in a dark visual field. strong reflected light from _O appears as a bright portion I _P.
Pair of bright portions I _P is used as the position correction information of the glass bottle W in performing the image processing by the image processing apparatus 16.

[0028] If the hair cracks along its circumference in the mouth portion W _O of the glass bottle W is present, as shown in FIG. 4 such was extracted enlarged mouth portion W _O of the glass bottle W, a light source 14 projection light from, and thus be strongly reflected at portions of the hair cracks W _C. Therefore, in the field of view of the imaging camera 15, a random irregular bright part I _U is generated due to hair cracks W _C that moves with the rotation of the glass bottle W in addition to the pair of the bright portions I _P. Defect determination unit 17, when detecting the presence of the amorphous bright part I _U determines that there is a defect in the glass bottle W.

[0029] In this embodiment, the light source 14 having an annular light projection surface 13 is disposed to the axis C _W coaxial glass bottle W, or the light source 14 to the light projection surface 13 becomes uniform light diffusing surface If it is, anything other than a ring can be adopted without any problem.

Further, in the above embodiment, since the projecting illumination light from just above the glass bottle W, as shown in FIG. 4, the circumferential hair cracks W _C is the mouth portion W _O of the glass bottle W when present in the direction, although large reflection light from hair cracks W _C is likely to occur, if the hair cracks W _C is present in the axial C _W direction of the mouth portion W _O of the glass bottle W, It becomes difficult to reflect this efficiently.

From the above, the axis C of the glass bottle W
If along the _W direction hair cracks W _C is present, another embodiment of the present invention which can favorably detected, will be described in detail with reference to FIGS.

As shown in FIG. 5 showing a schematic configuration of the present embodiment and FIG. 6 showing a plan configuration thereof, the outer periphery of a turning table 11 which is turned intermittently by a driving device (not shown) is provided with a barrel of a glass bottle W. part W semicircular notches 12 corresponding to _B are formed at equal intervals. The turntable 11 are set and the loading position and the test position P _C and unloading position of the glass bottle W, notches 1 in carrying position
2 glass bottle W before inspection is carried by the carrying conveyor (not shown), through the test position P _C, the glass bottle W of tested held in the notches 12 in the unloading position is carried out by out conveyor (not shown) You. Also, on the outer peripheral side of the turntable 11 from the carry-in position to the carry-out position,
A guide member (not shown) facing the outer periphery of the swivel table 11 with a predetermined gap therebetween is provided, and the glass bottle W is held between the guide member and the notch 12. It is conveyed intermittently in the unloading position from the loading position through the inspection position P _C.

[0033] wherein the test position P _C, bottle rotating device (not shown) for rotationally driving the glass bottle W in the axial C _W around is provided, the glass bottle W in the inspection position P _C
Is rotated one or more revolutions around its axis C _W.

[0034] On the side of the glass bottle W in the inspection position P _C, a light source 14 having a rectangular light projection surface 13 are arranged obliquely upward, a uniform diffused light from the light projection surface 13 is projected optical axis C _L of the light source 14 is in a state inclined relative to the horizontal plane. In addition, the obliquely above the glass bottle W in the inspection position P _C, is disposed an imaging camera 15 for imaging the mouth portion W _O of the glass bottle W, mouth W _O to be imaged by the imaging camera 15 Is read by the image processing device 16, and the presence / absence of a hair crack is determined by the defect determination device 17. Incidentally, the axis C _W of the glass bottle W in the inspection position P _C, the optical axis C of the light source 14
_L and the optical axis C _C of the imaging camera 15 are all set to be located on the same plane.

As shown in FIG. 7 to an example of the above-described reflected image represented schematically, mouth W _O of the reflection image captured by the imaging camera 15 is stronger from the mouth portion W _O in the central portion of the dark-field It reflected light appears substantially symmetrical as bright portion I _P. The bright portion I _P is used as the position correction information of the glass bottle W in performing the image processing by the image processing apparatus 16.

[0036] If a glass bottle W hair cracks W _C along its axial C _W direction to the mouth portion W _O are present, as shown in FIG. 8 mouth W _O was extracted expanding such a glass bottle W , projection light from a light source 14, so that the strongly reflecting at portions of hair cracks W _C. For this reason, in the field of view of the imaging camera 15, in addition to the brilliant part I _P , a random irregular brilliant part I _U due to the hair crack W _C moving with the rotation of the glass bottle W is generated. Defect determination device 17
When the presence of the irregular shaped luminous portion I _U is detected,
It is determined that the glass bottle W has a defect.

[0037]

According to the defect inspection method of the present invention, the light-transmissible container to be inspected is rotated around its axis, and the illumination light is projected from directly above the container to be inspected, and the illumination light is projected obliquely from above the container to be inspected. Since the presence / absence of a defect in the container to be inspected is determined by obtaining a reflection image of the container to be inspected, the presence / absence of a defect occurring along the circumferential direction of the container to be inspected is reliably detected quickly and at low cost. be able to.

Similarly, according to the defect inspection method of the present invention,
The light-transmissible container to be inspected is rotated about its axis, and illumination light is projected from obliquely below the container to be inspected, and a reflection image of the container to be inspected is obtained from obliquely above the container to be inspected, and the defect of the container to be inspected The presence / absence of the defect is determined, so that the presence / absence of a defect that occurs along the axial direction of the container to be inspected can be quickly and reliably detected at low cost.

According to the defect inspection apparatus of the present invention, the light source for projecting illumination light downward from above the light-transmissive container to be inspected carried into the inspection area, and the container to be inspected obliquely from above the inspected container. Imaging optical system for obtaining a reflected image of the container, container rotating means for rotating the container to be inspected one or more rotations around its axis in the inspection area, and detecting the presence or absence of a defect in the container to be inspected based on the reflected image from the imaging optical system The presence or absence of a defect occurring along the circumferential direction of the container to be inspected can be quickly and reliably detected at low cost.

Similarly, according to the defect inspection apparatus of the present invention,
A light source for projecting illumination light from obliquely below the light-transmissive container to be inspected carried into the inspection region, an imaging optical system for obtaining a reflection image of the inspected container from obliquely above the inspected container, and Since the container rotating means for rotating the inspection container one or more rotations around its axis and the judging means for detecting the presence or absence of a defect in the inspection container based on the reflected image from the imaging optical system are provided, the axial direction of the inspection container Can be quickly and reliably detected at low cost.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a schematic structure of an embodiment of a defect inspection apparatus according to the present invention.

FIG. 2 is a plan view of the embodiment shown in FIG.

FIG. 3 is a schematic diagram illustrating an example of a reflection image in the embodiment illustrated in FIGS. 1 and 2.

FIG. 4 is an enlarged enlarged view of a mouth of a glass bottle.

FIG. 5 is a conceptual diagram showing a schematic structure of another embodiment of the defect inspection apparatus according to the present invention.

6 is a plan view of the embodiment shown in FIG.

FIG. 7 is a schematic diagram illustrating an example of a reflection image in the embodiment illustrated in FIGS. 5 and 6.

FIG. 8 is an enlarged enlarged view of the mouth of the glass bottle.

[Explanation of symbols]

11 turntable 12 notch 13 light projecting surface 14 light source 15 imaging camera 16 image processing apparatus 17 defect detection device W glass bottle W _B torso W _O port portion W _C hair crack P _C inspecting position C _W axis C of the glass bottle optical axis I _P bright portion I _U irregular bright portion of the optical axis C _C imaging camera _L source

Claims (10)

[Claims] 1. A step of rotating a light-transmissive container to be inspected around its axis, a step of projecting illumination light onto the container to be inspected from directly above the container to be inspected, and an obliquely upward direction of the container to be inspected. A step of obtaining a reflection image of the container to be inspected from the apparatus; and a step of determining the presence or absence of a defect in the container to be inspected based on the reflection image of the container to be inspected. 2. The defect inspection method according to claim 1, wherein the illumination light is projected from a light source having an annular light projection surface coaxial with an axis of the container to be inspected. . 3. The defect inspection method according to claim 1, wherein the defect of the container to be inspected is a hair crack generated along a circumferential direction of a mouth portion. 4. A light source positioned above a light-transmissive container to be inspected carried into the inspection area and projecting illumination light downward on the container to be inspected, and a light source disposed obliquely above the container to be inspected. An imaging optical system for obtaining a reflection image of the container to be inspected, container rotating means for rotating the container to be inspected one or more rotations around the axis thereof in the inspection area, and an imaging system based on the reflection image from the imaging optical system. A defect inspection apparatus comprising: a determination unit configured to detect the presence or absence of a defect in an inspection container. 5. The defect inspection apparatus according to claim 4, wherein the light source has a light projection surface formed in an annular shape coaxial with an axis of the container to be inspected. 6. A step of rotating a light-transmissive container to be inspected around its axis, a step of projecting illumination light onto the container to be inspected from an oblique lower side of the container to be inspected, and an obliquely upward direction of the container to be inspected. A step of obtaining a reflection image of the container to be inspected from the apparatus; and a step of determining the presence or absence of a defect in the container to be inspected based on the reflection image of the container to be inspected. 7. The defect inspection method according to claim 6, wherein an axis of the container to be inspected, an axis of the illumination light, and an axis in an observation direction for obtaining a reflected image are on the same plane. . 8. The defect inspection method according to claim 6, wherein the defect of the container to be inspected is a hair crack generated at a mouth of the container along the axis. 9. A light source positioned obliquely below a light-transmissive container to be inspected carried into an inspection area and projecting illumination light obliquely upward to the inspected container, and disposed obliquely above the inspected container. An imaging optical system that obtains a reflection image of the container to be inspected, a container rotating unit that rotates the inspection container one or more rotations around its axis in the inspection area, and a reflection image from the imaging optical system. A defect inspection apparatus comprising: a determination unit configured to detect presence / absence of a defect in the inspected container. 10. The defect inspection apparatus according to claim 9, wherein an axis of the container to be inspected, an axis of the illumination light, and an axis of the imaging optical system are on the same plane.