JPH0731135B2 - Defect detection device for bottle body - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention is directed to defects in the body of a bottle, such as bubbles and transparent foreign matter generated in the wall thickness, sticking (notches or protrusions), seams, and burns on the outer surface of the body, inner surface of the body. The present invention relates to a device for optically detecting a body wire (convex stripes) generated on a wire or a protrusion due to unmelted matter.

2. Description of the Related Art As a device of this type, the present applicant has already proposed a device described in Japanese Patent Laid-Open No. 63-109352. This device projects divergent projection light onto the body of a rotating bottle, and the transmitted light from the body of the bottle is received by two rows of light receiving element groups arranged on the screen, and the first row of light receiving element group is received. Delays the electric signal from to match the phase with the electric signal from the light receiving element group in the second row,
Both electric signals are subtracted, and the presence or absence of a defect is determined from the subtraction result, that is, the difference in brightness.

[Problems to be Solved by the Invention]

The glass bottle manufacturing process includes a manufacturing process often applied to a wide-mouthed bottle called a press and plow and a manufacturing process often applied to a narrow-mouthed bottle called a blow-and-blow. However, the above-mentioned conventional method makes clear the difference in light and darkness of transmitted light due to the defect generated on the uniform wall surface of the inner and outer walls of the bottle manufactured by the press and blow process with good cylindricity. Although it can be detected, it is practically impossible to apply it to a bottle having a large irregularity on the inner surface called a settle line, which is peculiar to a bottle manufactured by a blow and blow process. It is an object of the present invention to enable accurate and accurate detection of defects such as those mentioned at the beginning that occur in the body of a bottle manufactured in a blow and blow process.

[Means for Solving the Problems]

The bottle body defect detecting apparatus according to the present invention comprises a bottle rotating means 2 for rotating a bottle 1 and a strip-shaped light on a rotating bottle body 1a.
A pair of projecting parts 7 for projecting 11 and an inspection site of the bottle body part 1a
The image pickup device camera 4 is directed to the image pickup device 13, and the light blocking member 16 is disposed between the image pickup device camera 4 and the bottle 1 in the vicinity of the inspection site 13. The light-shielding member 16 has a vertically long thin light-transmitting portion 14 in the visual field of the image pickup device camera 4 that allows refraction / scattered light that has passed through the inspection region 13 of the bottle body 1a to pass therethrough. Each light projecting unit 7 has an optical fiber array 8 in which a large number of optical fibers are arranged vertically in order to make the light from the light source 6 into a thin vertically elongated band light in the axial direction of the bottle 1, and this optical fiber array 8
It has a mirror 9 for reflecting the band-shaped light from and directing it to the inspection site 13 of the bottle body 1a, and a cylindrical lens 10 for making the light from the mirror 9 focus at the inspection site 13 of the bottle body 1a. . The band-shaped light 11 from the pair of light projecting portions 7 is once transmitted through the bottle body portion 1a, passes through the inside of the bottle, and intersects the inspection site 13 at an angle θ, and is the same as the visual field center line 12 of the image pickup device camera 4. The angle is adjusted by the mirror 9 so that the angle becomes θ / 2.

[Action]

The operation of the above configuration is as follows. The band-shaped light projected from the outside of the field of view of the imaging device to the bottle body is
In the normal case where there is no defect, the light passes through the bottle body as it is with almost no refraction or scattering, so the transmitted light is blocked by the light blocking member and does not enter the imaging device. However, if there are structural defects such as bubbles or burns on the bottle body, the light will be refracted there, and if there are surface defects such as scratches or stains, the light will be scattered there. Light enters the image sensor camera through the light transmitting portion of the member, and a defect is detected. Since the two strips of light pass through the body of the rotating bottle while intersecting at a predetermined angle, the defects in the body of the bottle extend over a long range in the vertical direction and are not affected by the directionality of the refracted light due to the defects. Can be detected. Also, since these strips of light will enter the bottle from somewhere on the bottle body and will pass through the inspection area of the bottle body again, if there is a defect in the first light entering part of the bottle body. Will be refracted first there, but since there are almost no defects at the same time in the light-incident part of the two strips of light, there are more than a predetermined number of defects to be detected.
It is possible to detect accurately without being affected by small (allowable range) defects in the light incident part or seams generated by molding. By placing a light-shielding member having a vertically long thin light-transmitting part in the vicinity of the inspection part of the bottle body, the inspection field of view of the image sensor camera was limited to a narrow range of the bottle body. Refracted light due to a step or the like can be removed, and only the defect to be detected can be accurately and accurately detected by removing excess light.

【Example】

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 (plan view) shows a first embodiment of the present invention, in which a bottle 1
Is rotated by a drive wheel 2 which is a bottle rotating means while standing vertically at the inspection position. A light projector 3 is installed on one side of the bottle 1 and an image pickup device camera 4 as an image pickup device in which image pickup devices such as CCDs are arranged in a linear array or a matrix is installed on the other side. The image sensor camera 4 is provided with a lens 5 and images through the lens 5. The electric signal from the image pickup device group can be digitally processed by using a computer. The light projector 3 has a pair of light projecting portions 7 arranged in mutually opposite directions for projecting the light from the light source 6 into strip light. Each light projecting unit 7 has an optical fiber array 8 in which a large number of optical fibers are vertically arranged in order to make the light from the light source 6 into a vertically elongated strip-shaped light parallel to the center line of the bottle 1, and the direction of the band-shaped light. Mirror 9 for changing the direction and directing it to the inspection portion 13 of the body 1a of the bottle 1, and the cylindrical lens 10 for making the strip light from this mirror 9 focus at the inspection portion 13 of the bottle body 1a.
Composed of and. Although the two optical fiber arrays 8 are arranged apart from each other in the length direction in the figure, the light projecting device 3 can be miniaturized by disposing them so as to face each other so as to overlap each other. Two strips of light 11 from both light projecting units 7 are obliquely projected from the outside of the visual field of the image pickup device camera 4. That is, two strips of light
Reference numeral 11 indicates a point where the visual field center line 12 of the image pickup device camera 4 intersects with the bottle body 1a, that is, the inspection site 13 crosses each other at a predetermined angle θ, and the same angle (θ / 2 ) Is adjusted by the mirror 9. A first light shielding member 16 having vertically elongated slits 14 and 15 serving as a light transmitting portion is provided between the bottle 1 and the image pickup device camera 4.
And the second light shielding member 17 are arranged vertically. The first light blocking member 14 is installed near the inspection site 13 of the bottle body 1a, and the second light blocking member 14 is installed near the lens 5 of the image sensor camera 4. Moreover, these light shielding members 16 and 17
Are placed so that the centers of the slits 14 and 15 are located on the visual field center line 12. The slit 14 of the first light blocking member 16 is narrower than the slit 15 of the first light blocking member 17,
Further, on both side edges of the slit 14, lips 18 projecting toward the bottle 1 side are provided so as to be gradually narrowed. This lip 18 may be omitted. Therefore, the two strips of light 11 enter the rotating bottle 1 from a portion different from the inspection site 13, pass through the bottle 1, and cross and pass through the inspection site 13. When there is no defect in the bottle body 1a at this inspection site 13, two strips of light 11
Since the light passes through the bottle body 1a almost as it is, the transmitted light is shielded by the first light shielding member 16 out of the slit 14 of the first light shielding member 16. However, the bottle body 1a has bubbles as shown in FIG. 2, joint bite as shown in FIG. 3, sticking as shown in FIG. 4 (notches and protrusions on the outer surface), and as shown in FIG. If there are structural defects such as glassy stones and other foreign matter, inner body wires as shown in FIG. 6, and inner protrusions due to unmelted material as shown in FIG.
11 is greatly refracted and is scattered when the bottle body 1a has a surface defect such as dirt due to scratches, the refracted / scattered light 19 passes through the slit 14 of the first light shielding member 16. Then, of the transmitted light, only the light that has further passed through the slit 15 of the second light shielding member 17 is imaged by the image pickup device group of the image pickup device camera 4 through the lens 5.
In this case, since the bright part in the dark field of view is detected, the hardware of the detection circuit and the algorithm for determining the presence / absence of a defect can be simplified based on the amount of light. Therefore, if the light passing through the slit 14 of the first light shielding member 16 includes the light 20 having a relatively small refraction angle due to the molding joint as shown in FIG.
The second light blocking member 17 blocks the light. Angle above θ / 2
The refracted light 20 due to such a joint is the image sensor camera
Adjust so that light does not enter. Although the angle varies depending on the type of bottle 1, etc., about 11 degrees was preferable in the experiment. By using two strips of light 11 and projecting them at a predetermined angle θ so as to cross each other on the bottle body 1a, it is possible to detect without being influenced by the directionality of refracted light due to defects, and the following advantages There is. That is, the two strips of light 11 enter the bottle from the place where the bottle body 1a is present as described above, and the other portion of the bottle body 1a again, that is, the inspection site where the two strips of light 11 cross each other Since the light is transmitted through 13, if there is a defect in the first light incident part in the bottle body 1a, it will be refracted first and the irradiation light amount to the inspection site 13 will be reduced. Since there are almost no simultaneous defects in the 11 light incident parts,
It is possible to detect a predetermined or more defect to be detected without being affected by a small (allowable range) defect in the light incident portion or a seam. The first and second light blocking members 16 and 17 may be those in which a transparent portion serving as a light transmitting portion is provided in a part of an opaque plate. Further, even one light-shielding member can achieve the intended purpose, and there may be three or more, and the number thereof can be arbitrarily selected.

【The invention's effect】

The present invention has the following effects. Since the two strips of light pass through the inspection part of the rotating bottle body while intersecting at a predetermined angle, the defects in the bottle body are extended in the longitudinal direction and the direction of the refracted light due to the defect is changed. It can be detected without being affected. If there is a defect in the first light incident part of the bottle barrel, the band-shaped light will be refracted first there, but since there is almost no simultaneous defect in the two light-incident parts of the band-shaped light, it is detected. It is possible to detect a predetermined or more defect to be detected without being affected by a small (allowable range) defect in the light incident portion or a seam generated by molding. By placing a light-shielding member having a vertically long thin light-transmitting part in the vicinity of the inspection part of the bottle body, the inspection field of view of the image sensor camera was limited to a narrow range of the bottle body. Refracted light due to a step or the like can be removed, and only the defect to be detected can be accurately and accurately detected by removing excess light. It is possible to project thin vertically elongated strip-shaped light from the optical fiber array of the light transmitting portion onto the inspection portion of the bottle body with good directivity by the mirror and the cylindrical lens. By using an optical fiber array in which a large number of optical fibers are arranged vertically, it is possible to make a strip-shaped light with an even amount of light in the vertical direction, and to make the light projecting portion generate little heat and have a large amount of light. The band-shaped light from the optical fiber array is adjusted by the mirror so as to be directed to the inspection part of the bottle body, and the focus is adjusted by the cylindrical lens, so that the pair of light projecting parts are
It can be placed as close as possible to the bottle transport line, even in small installation locations. Not only defects of bottles manufactured by press and plow but also defects of bottles manufactured by blow and blow, and defects with a large refractive index such as bubbles and sharp projections with unevenness can be detected. . Since the bright portion in the dark field of view is detected as a defect, the hardware of the detection circuit and the determination algorithm for the presence / absence of a defect can be simply determined by the amount of light.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of an embodiment of the present invention, FIGS.
The figures are sectional views showing the modes of defects in the bottle body, respectively.
The drawing is a cross-sectional view showing a seam formed by molding. 1 ... Bottle, 1a ... Bottle body, 2 ... Drive wheel (bottle rotating means), 4 ... Image sensor camera, 6 ... Light source, 7 ... Projector, 8 ... Optical fiber array, 9 ...... Mirror, 10 …… Cylindrical lens, 11 …… Band light, 13
…… Inspection site, 14 …… Slit (translucent part), 16 …… Shading member.

Claims (1)

[Claims] 1. A bottle rotating means 2 for rotating a bottle 1, and a pair of light projecting portions 7 for projecting a band-shaped light 11 on a rotating bottle body 1a.
And an image pickup device camera 4 directed to the inspection portion 13 of the bottle body 1a, and a light shielding member 16 arranged in the vicinity of the inspection portion 13 between the image pickup device camera 4 and the bottle 1. The light-shielding member 16 has a vertically long thin light-transmitting portion 14 in the visual field of the image pickup device camera 4, which transmits refracted / scattered light that has passed through the inspection portion 13 of the bottle body portion 1a. An optical fiber array 8 in which a large number of optical fibers are arranged vertically in order to make the light from the light source 6 into a vertically elongated strip-shaped light in the axial direction of the bottle 1, and the strip-shaped light from the optical fiber array 8 is reflected to reflect the strip-shaped light. Examination site 13 of part 1a
Mirror 9 that is directed to and the light from mirror 9
1a has a cylindrical lens 10 for focusing at the inspection site 13, and the band-shaped light 11 from the pair of light projecting units 7 once passes through the bottle body 1a and passes through the bottle to pass the inspection site 13. The device for detecting a defect in a bottle body is characterized in that the mirror 9 is adjusted so as to intersect with the above at an angle θ and to have the same angle θ / 2 with respect to the center line 12 of the visual field of the image pickup device camera 4. .