JPH043820B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a bottle opening inspection device, and more specifically, a bottle opening inspection device that illuminates a bottle conveyed on a straight line from the side and inspects the bottle opening. The present invention relates to an inspection device that inspects defects such as chips and burrs (cracks formed inside glass) by capturing an image from the top surface and processing the image.

[Conventional technology]

Conventionally, this type of inspection equipment has either placed a photo sensor near the bottle mouth and rotated the bottle at the sensor position to inspect the entire surface of the bottle, or illuminated the bottle mouth in a ring shape from the top of the top, and There are known devices in which an image is captured from the upper part of the top surface using a television camera or the like, and an inspection is performed based on the captured image.

[Problem that the invention seeks to solve]

However, the former device requires a mechanism to rotate the bottles, and has the problem of slow processing speed (approximately 150 BPM [bottles/min]). Further, there are also problems such as the need for time and effort in switching the rotation and conveyance mechanism, adjusting the sensor position, etc. for each type of bottle.

On the other hand, the latter device has the following problems.
In other words, the top surface of the bottle mouth is not necessarily smooth;
Furthermore, since many of them have a certain curvature, it is difficult to uniformly illuminate the entire top surface, and therefore it is difficult to inspect for defects under the same conditions. In particular, cracks, or burrs, formed inside the glass are usually hardly visible when illuminated from above the top surface.

Therefore, this invention does not require a complicated mechanism such as rotating the bottle, can easily handle changes in bottle shape, can be inspected at high speed, and can detect defects in the bottle opening. It is an object of the present invention to provide an inspection device capable of sufficiently detecting any defects in any part.

[Means for solving problems]

A pair of illumination means for illuminating the bottle opening from both sides at a predetermined angle with respect to the direction of conveyance of a bottle having a substantially circular bottle opening that is transported in a predetermined direction; a first imaging system consisting of an imaging means for taking an image from the first imaging system; a second imaging system which is configured similarly to the imaging system and whose light irradiation axis by the illumination means differs by approximately 90 degrees from that of the first imaging system; Signal 2
An image processing device having a value converting means, a feature extracting means, and a masking means for masking a portion of the bottle opening that is directly irradiated with light is provided.

[Effect]

The image processing device binarizes the imaging signals from the first and second imaging systems, extracts appropriate feature quantities, masks the part of the bottle mouth that is directly irradiated with light, and features the parts that are not masked. Defects such as chips and cracks can be detected at high speed based on quantity, for example, area value.

〔Example〕

FIG. 1 is a schematic diagram showing an embodiment of the present invention, in which A is a top view and B is a side view. In addition, in the figure, 1 is an image processing device, 21, 2
2 is an imaging device such as a television camera, 3 is a bottle, 4
1 to 44 are illuminators.

Explain the operation.

First, the bottle 3 is directly transported in the direction of arrow R on the transport line LN. Two pairs of illuminators 41 and 42, and 43 and 44, whose irradiation axes are at an angle of, for example, 45 degrees with respect to the transport direction, are provided during the transport.
As a result, the side surface of the bottle opening B is illuminated. Therefore, illuminators 41 and 42 and illuminators 43 and 4
The irradiation directions of the light formed by 4 are orthogonal to each other, and there is a part that is directly hit by the light (this part is called a mask part because the light is directly reflected and cannot be inspected for defects) and a part that is not hit by the light. (If this part is normal, there will be no reflection, and reflection will be obtained only when there is a defect, so this part will be referred to as defect inspection area A.) By combining the inspection areas, the entire bottle opening can be inspected. One television camera 21, 22 is provided corresponding to each position, and images the bottle opening B. The image processing device 1 sequentially processes imaging signals from television cameras 21 and 22 and performs defect inspection.

FIG. 2 is a reference diagram for explaining the relationship between the illuminator that illuminates the bottle mouth and the light reflected from the bottle mouth. Note that A in the figure is a top view and B is a side view.

That is, when the bottle opening B is illuminated from both sides in a predetermined direction as shown in FIG.
Directly reflected light in the area directly exposed to light (mask area)
Lp is generated, but in the part (defect inspection area) A perpendicular to it, there is almost no reflected light if it is normal.
It can be seen that only when there is a defect F such as a chip or a crack, upward reflected light L _f is generated at the defect cross section.

FIG. 3 is a block diagram showing a specific example of an image processing apparatus. Here, 10 is an analog/digital (A/D) converter, 11 is an image position detector, and 12 is an analog/digital (A/D) converter.
13 is a mask generation section, 13 is an image memory, 14 is a defective image detection section, and 15 is an arithmetic processing section such as a microprocessor.

The processing operation when the image of the bottle opening B is shown as shown in FIG. 4 will now be described.

First, analog images from the television cameras 21 and 22 are converted by the A/D converter 10 into white, black, or bright/dark binary images according to their gray level, and are stored in the image memory 13. FIG. 4 shows the image data at this time in analog form. At this time, assuming that the direction of light irradiation from the illuminator is as shown in the figure, the image position detection unit 11 detects the points of change from dark to bright and from bright to dark in the first and third quadrants of the image capture screen G, respectively. position
C _d , C _l and the image width data of the bright area (reflection area) for each horizontal scanning line HS are extracted. The bright image width data at this time are shown as W ₁ and W ₃ in FIG. 4. The arithmetic processing unit 15 integrates the bright image width data from the image position detection unit 11 and calculates the area 2 minutes position DI.
In addition to finding this horizontal scanning line position (DI)
The center position P _p of the bright image is determined from the change point position data C _d and C _l of the image at . The mask generating section 12 forms a rectangular mask area MA as shown in FIG. 4 based on the center position data from the arithmetic processing section 15. The defective image detection unit 14 extracts the image area in the area excluding the mask area MA, that is, the defect inspection area A. At this time, if it is normal, the area extraction value by the defect detection unit 14 is approximately zero, but if there is a defect F such as a chip or a crack, the area value based on the reflected light from that part is extracted. Therefore,
If the arithmetic processing unit 15 compares this area value data with a predetermined set value, it can be determined whether or not there is a defect.

Thereafter, the same process as above is performed by changing the direction of light irradiation, and the results of both judgments are combined to complete the inspection of the entire bottle opening. At this time, it goes without saying that the second and fourth quadrants in FIG. 4 become the mask portion, and the first and third quadrants become the defect inspection areas.

〔Effect of the invention〕

According to this invention, when inspecting a bottle by transporting the bottle in a straight line, illuminating it from the side of the bottle mouth, and capturing an image from above the top surface using a television camera, etc., two sets of illuminators are arranged so that their irradiation axes are orthogonal to each other. As a result, a special mechanism such as rotating the bottle is not required, and as a result, the conveyance mechanism This has the advantage that it becomes easy to use, and the configuration of the entire system is simplified. Further, since the bottle is simply conveyed in a straight line, there is an advantage that even if the bottle shape changes, it is easy to change the bottle shape. Furthermore, since the bottle mouth is illuminated from the side surface and the light reflected from the cross section of the defect is used, inspection can be performed regardless of the smoothness or curvature of the bottle mouth, making it possible to perform highly accurate inspections. becomes. In addition, since the center of the image of the direct reflection part is found and masked, and the area value of the image is extracted in the inspection area other than this masked area to determine whether there is a defect, it requires particularly complex calculations. High-speed processing is possible without the need for processing.

[Brief explanation of drawings]

Figure 1 is a schematic diagram showing an embodiment of this invention, Figure 2 is a schematic diagram showing an embodiment of this invention.
The figure is a reference diagram for explaining the relationship between the illuminator that illuminates the bottle mouth and the light reflected from the bottle mouth. Figure 3 is a block diagram showing a specific example of the image processing device.
The figure is a reference diagram for explaining the image processing method according to the present invention. Description of symbols, 1... Image processing device, 21, 22...
...TV camera, 3...Bottles, 41-44...Illuminator, 10...A/D conversion section, 11...Image position detection section, 12...Mask generation section, 13...Image memory, 14... Defect image detection unit, 15... Arithmetic processing unit, A... Defect inspection area, B... Bottle mouth part,
P...Mask part, MA...Mask area, P _p ...
Image center position, C _d , C _l ... Change point position, W ₁ , W ₃
... Bright image width data, F ... Defect, G ... Imaging screen.

Claims (1)

[Scope of Claims] 1. A pair of illumination means for illuminating the bottle opening from both sides at a predetermined angle with respect to the conveyance direction of a bottle that is conveyed in a predetermined direction and has a substantially circular bottle opening; a first imaging system consisting of an imaging means for taking an image of the bottle opening from above; and a first imaging system configured similarly to the first imaging system, the axis of light irradiation by the illumination means being approximately 90 degrees from that of the first imaging system. and a different second imaging system,
An inspection device that inspects defects in a bottle opening by sequentially processing imaging signals from the first and second imaging systems in an image processing device, the image processing device at least processing the imaging signals into a predetermined format. a binarization means for binarizing the binarized image; a feature extracting means for extracting a predetermined feature from the binarized image; and a feature extracting means for extracting a predetermined feature from the binarized image; 1. A bottle mouth inspection device, comprising: mask setting means for masking, and inspecting defects from feature amounts of a portion of the bottle mouth other than the masked area.