JP2004028930A - Container foreign matter detecting device and container foreign matter detecting method - Google Patents

Abstract

Kind Code: A1 An inside of a container capable of suppressing a light-dark difference in an image due to an uneven distribution of the amount of light generated due to refraction or reflection of light coming from the shape of the container, and stably and correctly detecting foreign matter mixed in the container. It is an object of the present invention to provide a foreign matter detection device and a method for detecting foreign matter in a container.
Kind Code: A1 A container foreign object detection device for irradiating a transparent container 3 in which liquid is enclosed with illumination light and detecting a foreign object in the container from an image of the container 3 obtained by an image pickup means 2. The light source 1 for irradiating the illumination light is arranged on the side, and the imaging means 2 is arranged on the bottom side of the container 3.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for detecting foreign matter in a container and a method for detecting foreign matter in a container, which irradiates a transparent container filled with liquid with illumination light and detects foreign matter mixed into the container from an image of the container obtained by an imaging unit. It is.
[0002]
[Prior art]
The main foreign substances mixed into the container in which drinking water or the like is sealed are fragments of the container material at the stage of forming and manufacturing the container and parts of the device for filling the contents with the liquid and the component fragments. It is unlikely that foreign matter is mixed in the container, but since there is a possibility of adverse effects on the human body, it is required to reliably remove the foreign matter regardless of the frequency of occurrence.
[0003]
The conventional 100% inspection relies on human visual inspection. At this time, it is particularly difficult to detect, and most of the existing states are precipitated foreign substances. This is because the thickness of the bottom portion changes and there are steps at the bottom for the sake of molding the container, so that the container bottom itself is like a lens having a complicated shape.
[0004]
Japanese Patent Application Laid-Open No. 7-181145 discloses a conventional technique of irradiating a transparent container filled with liquid with illumination light instead of visual observation by a person and detecting foreign matter mixed into the container from an image of the container obtained by an imaging unit. Some are described in the gazette.
[0005]
This conventional technique obtains an image from a transparent container by the light transmission method, eliminates light and darkness due to uneven distribution of the amount of light generated by refraction and reflection of light caused by the shape of the container, and extracts foreign matter inside by image processing An optical correction element is incorporated in the light irradiation system so that it can be performed.
[0006]
As the optical correction element, a light irradiation system in which an imaging camera 2a is disposed on the lid side of the container 3 and an illumination light source 1a is disposed on the bottom side is larger than gas and substantially equal to the container material as shown in FIG. An optical correction element 7a made of a light-transmitting object having a large optical density is attached to the bottom of the container 3, or an optical correction liquid 7b is interposed at the bottom of the container 3 as shown in FIG.
[0007]
[Problems to be solved by the invention]
However, in the example shown in FIG. 17, the adhesion between the container 3 and the female optical correction element 7a poses a problem. If the gap is 1 (μm), light refraction occurs in the gas layer in the gap, and the expected effect is reduced. On the surface of the container, there are a large number of protrusions having different shapes caused by cutting in the container manufacturing process, surface scratches during transportation, printed characters, etc., and a small number of (μm) to several tens (μm) different surfaces for each container. Irregularities are present, causing gaps. Since the female optical correction element 7a cannot be individually prepared for surface irregularities that occur indefinitely, and there are at most several types, it is difficult to achieve perfect close contact with no gap between containers.
[0008]
Even if the gap between the container and the optical correction element is mechanically compressed to eliminate the gap, the container is molded and manufactured to minimize the thickness in order to reduce the weight and the amount of material used. Due to the limitation of the compression force, complete close contact by compression is also difficult.
[0009]
In the example shown in FIG. 18, minute air bubbles may be formed in the optical correction liquid or on the outer surface of the container, resulting in an optical disturbance, and an increase in the inspection time due to the addition of a disturbance processing method, and an increase in the inspection time. This leads to a decrease in accuracy stability. For containers used in the food and medical fields, sanitary management of the optical correction liquid 7b is necessary, and the operating cost of the apparatus increases.
[0010]
In the case of the X-ray method in which the energy is high and the linearity at the time of transmission is extremely short at a very short wavelength, the X-ray transmittance of the container is usually the same as that of the container.
[0011]
Therefore, an object of the present invention is to suppress a difference in brightness in an image due to an uneven distribution of the amount of light generated due to refraction or reflection of light coming from the shape of the container, and to stably correctly detect foreign matter mixed in the container. It is an object of the present invention to provide an apparatus for detecting foreign matter in a container and a method for detecting foreign matter in a container that can perform the method.
[0012]
[Means for Solving the Problems]
A feature of the apparatus of the present invention that achieves the above object is that a transparent container in which a liquid is sealed is irradiated with illumination light, and a foreign object in the container is detected from the image of the container obtained by the imaging means. In the detection device, a light source for irradiating illumination light is arranged on a lid side of the container, and an imaging unit is arranged on a bottom side of the container.
[0013]
A feature of the method of the present invention that achieves the above object is to illuminate a transparent container filled with a liquid with illumination light and detect foreign matter in the container from an image of the container obtained by the imaging means. In the foreign matter detection method, a first image at an amount of illumination light not exceeding the luminance limit in the imaging unit and a second image at an illumination light amount exceeding the luminance limit in the imaging unit are obtained and set as a second image. An object of the present invention is to detect an image of an object having a luminance not exceeding an arbitrary threshold value as a foreign substance.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on an embodiment shown in the drawings.
[0015]
1 to 3 show a first embodiment, in which a transparent PET container 3 is conveyed sequentially and continuously on a conveyor 11. The container mounting portion 33 of the transport conveyor 11 uses a transparent acrylic material. Alternatively, a transparent, chemically and mechanically strong material such as vinyl chloride or glass may be used. The container 3 is already filled with liquid contents, which are mainly medicines and beverages, and is further sealed with a container lid 4.
[0016]
The foreign substance detection is performed immediately after the container lid 4 is sealed. Normally, in the process of detecting foreign matter, there is no printed matter or the like on the surface of the container that becomes an optical obstacle, and the printed matter or the like is often applied only to a container that has become good in foreign matter detection. In addition, the container and the contents (the liquid sealed in the container) which are the objects of the present embodiment are both transparent, but are not limited to colorless and transparent, colored and transparent, and opaque in general environmental light. Even in such a case, the foreign matter can be detected according to the degree of light transmission.
[0017]
The container 3 in which foreign matter has been confirmed is removed from the container conveyor 11 or a defect identification mark serving as a mark is added to a prominent position of the container 3 so as to be discharged in a later process.
[0018]
At a foreign substance inspection position 12 on the conveyor 11, light from an illumination light source 6 having a halogen lamp is emitted from the illumination light irradiation unit (illumination light irradiation means) 1 to the upper part of the container 3 via the light guide 5. As the illumination light source 6, a fluorescent lamp, an LED, an EL, an incandescent lamp, a metal halide lamp, an infrared lamp, an ultraviolet lamp, or the like is used in addition to the halogen lamp.
[0019]
The inside of the light guide 5 is a state in which about hundreds of optical fibers are bundled, and the optical fibers are divided by the illumination light irradiating unit 1 and fixed in a ring shape with the tips of the optical fibers facing directly below. Since the light has a certain spread angle at the tip of the optical fiber, as shown in FIG. 2, as the distance from the illumination light irradiating section 1 increases, the transmitted illumination light 10 gradually changes from a ring shape to a circular shape. At this time, since the tip of the optical fiber is arranged in a ring shape in the illumination light irradiation unit 1, the shadow of the container lid 4, which may be made of an opaque material, is not projected on the bottom side of the container. Does not. In order to further avoid the influence of the shadow of the container lid 4 being projected on the bottom side of the container, the ring-shaped arrangement diameter in the illumination light irradiation unit 1 is preferably set to be larger than that of the container lid 4.
[0020]
An imaging camera (imaging means) 2 that images the container 3 through the container mounting location 33 is disposed below the conveyor 11. In this embodiment, the bottom of the container 3 is in contact with the container mounting location 33, and the illumination light irradiation unit 1 is arranged on the container lid 4 side.
[0021]
On the conveyor 11, the container presence / absence detection sensor 13 detects that the target container 3 has reached the foreign object detection position 12. As the type of the container presence / absence detection sensor 13, a transmitted light type or an ultrasonic type may be used in addition to the reflected light type shown in the figure.
[0022]
The detection result of the container presence / absence detection sensor 13 is grasped by the main arithmetic unit 19 via the I / O interface 23 shown in the detection device control unit 30 of FIG. Of the shutter signal. An image of the container 3 is captured by the imaging camera 2 based on the shutter signal, and is temporarily stored in the storage device of the image information processing unit 20 that performs image processing from the imaging camera controller 15 via the camera interface 17. Perform extraction processing. The captured image and the video that has already been processed are displayed on the image processing monitor 18. The start, stop, and error of the apparatus are managed by the operation switch 31 and the display lamp 32, and the main arithmetic unit 19 and the main storage unit 21 manage these operations and the operation status of the entire apparatus including image processing of video. ing. The operation status of the entire apparatus is displayed on the monitor 22.
[0023]
Returning to FIG. 1, the foreign matter inspection position 12 and its surroundings are surrounded by a light-shielding cover 34 so as to block light from the surroundings, which is an optical disturbance to the container 3 and the imaging camera 2, so that stable foreign matter detection can be performed. ing.
[0024]
FIG. 4 shows a state of the foreign matter 8 mixed in the container 3. As described above, the foreign matter 8a precipitated on the bottom 3a is the most common, and the foreign matter 8b floating on the liquid surface and the foreign matter 8c floating on the liquid are the next most.
[0025]
Hereinafter, detection of the precipitated foreign matter 8a will be described.
FIG. 5 shows an example of an image obtained by the imaging camera 2 of the precipitated foreign matter 8a.
In FIG. 5, a substantially circular white circle indicates the outline of the container 3. In the outline, 9 surrounded by a solid line is a shadow (image) of the precipitated foreign matter (object) 8 a, and the other light black portions are those of the container 3. This is a dark area (image) in which the irradiation light is scattered due to the shape and the amount of light is reduced. However, there is no shadow of the container lid 4, and the precipitated foreign matter 8a can be clearly captured. The shadow 9 of the foreign matter and the dark area can be distinguished by the shape.
[0026]
Next, a second embodiment in which the shadow 9 of the precipitated foreign matter 8a is more clearly grasped by image processing will be described.
In this embodiment, an image is obtained at least twice by changing the output in the illumination light irradiation unit 1. Specifically, the light amount is increased, and the halation phenomenon in which the brightness is high and the image becomes white for the imaging camera 2 is positively generated.
[0027]
FIG. 6A shows a luminance distribution at a position where a foreign substance exists along the line II in the example of FIG.
The luminance distribution along the line I-I in FIG. 6A is as shown in FIG. 6A under normal illumination, and not only the luminance decreases at the foreign matter portion, but also the occurrence of dark areas due to the shape of the container bottom 3a. As a result, the luminance is reduced even at locations other than the foreign matter. This means that, in a pattern matching process using a binarized image in which the shading of an image is divided by a fixed luminance threshold or a shading image, dark portions other than the original foreign image 9 are also recognized as foreign objects, resulting in an incorrect detection result. turn into.
[0028]
Therefore, the image shown in FIG. 7 is obtained by increasing the output of the illumination light irradiation unit 1.
At this time, the output of the illumination light irradiation unit 1 is set to an output value of the illumination light source 1 such that the luminance at the container bottom 3a exceeds the sensitivity limit of the imaging camera 2. Then, the luminance distribution on the II line becomes a saturated state exceeding the sensitivity limit of the imaging camera 2 as shown in FIG.
[0029]
In FIG. 7, the brightness of the shadow (image) of the foreign matter remains small because the illumination light is blocked by the foreign matter. However, in the present embodiment, the brightness of the dark area (shadow) derived from the shape of the container bottom 3a that has appeared in FIG. 6A is improved in the present embodiment, exceeds the threshold, and the dark area disappears. In this state, processing is performed using a binarized image in which shading of the image is divided by the threshold value of luminance.
[0030]
As the luminance threshold at this time, an appropriate value is derived in advance depending on the shape of the container, the type of liquid, the type of foreign matter, and the like. FIG. 8 shows a binarized image in which a portion having a luminance equal to or higher than the threshold is indicated by white, and a portion having a luminance lower than the threshold is indicated by black. The black object 9b in FIG. 8 is a detected foreign matter.
Even if the brightness values other than the foreign matter have some magnitude, they are all greater than or equal to the threshold value and have no relation to the brightness value at the foreign matter portion. Therefore, the influence of the dark part derived from the shape of the container bottom 3a is apparently eliminated, and the foreign matter is removed. 8 can be reliably detected.
[0031]
Since the finally recognized luminance is transmitted through both the imaging camera 2 and the camera interface 17, it is sufficient that one of the two exceeds the luminance sensitivity limit.
In the case of the imaging camera 2, even if the setting exceeds the luminance limit of the imaging data by adjustment on the camera interface 17 side within the range not exceeding the sensitivity limit, exactly the same effect occurs. In particular, when the sensitivity exceeds the sensitivity limit of the imaging camera 2, it is necessary to consider the life of the imaging camera 2, and it is desirable that the lifetime slightly exceeds, specifically, exceeds 5% to 10%.
[0032]
Third and fourth embodiments corresponding to differences in the outer diameter of the container 3 will be described.
FIG. 9 shows an illumination light irradiation unit (illumination light irradiation means) 1 according to the third embodiment.
In this embodiment, the tip of the optical fiber in the illumination light irradiating section 1 is arranged concentrically over the whole from the center to the outside. The optical fiber bundles are grouped according to the distance from the center.
[0033]
In the example of FIG. 9, two rows are grouped as one group, and the light guide 5 is formed as one set. The other end of the optical fiber bundle for each group is connected to a different illumination light source. FIG. 6 shows an example in which the halogen lamp in the illumination light source connected to the second group is turned on from the outside and turned on, and the halogen lamp in the illumination light source connected to the remaining groups is turned off and all are turned off.
[0034]
When the outer diameter of the container 3 is large, the transmitted illumination light 10 is emitted only from the outer optical fiber group, and when the outer diameter of the container 3 is small, the transmitted illumination light 10 is emitted from the inner optical fiber group. Therefore, it is possible to cope with a difference in the outer diameter of the container 3 conveyed on the conveyor 11 without replacing the light guide. If the number of times the illumination light source is turned on and off affects the life of the illumination light source, a separately provided shutter is installed between the illumination light source and the light guide while the individually prepared illumination light source is always turned on, and the illumination light source is individually turned on. The same function may be satisfied by turning off.
[0035]
FIG. 10 shows a fourth embodiment.
In this embodiment, two illumination light irradiation units (illumination light irradiation means) 1a and 1b having different diameters are provided.
At the foreign matter inspection position 12 on the conveyor 11, two sets of illumination light irradiation parts 1 a and 1 b are installed on the container 3 from the illumination light sources 6 a and 6 b having halogen lamps via the light guides 5 a and 5 b and transmitted. The illumination light 10 is irradiated from above the container 3. The inside of the light guides 5a and 5b is a state in which several hundreds of optical fibers are bundled like the light guide 5, and the optical fibers are divided by the illumination light irradiating units 1a and 1b, and the configuration is the same as that of FIG. The transmitted illumination light 10 is arranged so as not to overlap with the container lid 4 and the illumination light irradiation unit 1.
[0036]
Irradiation and non-irradiation of the transmitted illumination light 10 are performed by turning on / off the power of each halogen lamp in the illumination light sources 6a and 6b, or by turning on / off a shutter (not shown) provided between the illumination light irradiation units 1a and 1b and the light guides 5a and 5b. You can select by turning off. The amount of each transmitted illumination light 10 emitted from the illumination light irradiation units 1a and 1b is the same or different depending on the shape of the container.
[0037]
In these embodiments, the foreign matter can be detected not only by detecting the foreign matter according to the size of the container, but also by using the second embodiment in which the light amount is increased.
[0038]
Next, a fifth embodiment in which foreign matter detection is performed by increasing the amount of light will be described. When the container 3 arrives at the foreign object inspection position 12 by the container presence / absence detection sensor 13 on the conveyor 11, first, the first transmission illumination light irradiation is performed, and the foreign matter and the dark portion coming from the container shape are displayed on the screen. For all of them, a value below a certain threshold is binarized as a black object, and the area of each black object is temporarily stored. The black object includes both the foreign matter and the dark part coming from the shape of the container 3, and the stored image is shown in FIG. 11A, which is an image composed of many black objects.
[0039]
Next, the second transmitted illumination light irradiation with the increased light amount is performed, and the same threshold value is similarly used for the entire area of the screen, and the area below each threshold value is set as a black object, and the area of each black object is stored. As shown in FIG. 11B, in the second video, the black object is small and the image is small.
[0040]
Due to the difference in the amount of transmitted illumination light, the black object image in each image has a large area in the first image of the black object, and has a small area and a small number in the second transmission illumination light irradiation. In this case, the area reduction rate differs for each black object in the video screen, but the area reduction rate increases or disappears completely in a dark part coming from the shape of the container at the container bottom 3a that transmits light. On the other hand, the area reduction rate is small at a foreign matter portion that blocks light. Only the image of the black object having a small area reduction rate is determined as a foreign substance, and can be detected as an original foreign substance.
[0041]
In the example of FIG. 11, as a result of determining that the area reduction rate is 20% or less as a foreign substance, the result is the same as the image of FIG. The area reduction rate may be usually set to 10% to 30% as a criterion.
[0042]
In the above-described embodiment, when the shutter speed of the imaging camera 2 is increased in accordance with the increase of the transport speed of the transport conveyor 11, the foreign object detection in a state where the light amount to the imaging camera 2 exceeding the sensitivity limit cannot be obtained. This embodiment is also effective when it is possible to detect a foreign substance having a smaller size and to improve the detection accuracy.
[0043]
The stepwise switching of the light amount of the transmitted illumination light 10 may be any of the above-described addition method at the same position, the switching method, and execution at a different foreign substance inspection position 12. Further, in the present embodiment, the difference in the light amount is set to two stages. However, when the same black object is obtained in the binarized image because the dark portion coming from the container shape and the foreign matter overlap, the difference in the light amount is set to three or more stages. The detection accuracy can be further improved by comparing the area reduction rate with the average value and treating it while checking the change in the number of black objects.
[0044]
Next, a method for detecting whether or not there is a foreign substance by image processing will be described.
The original video is the same as that in FIG. 5, and the processing is actually performed on the entire same grayscale image. However, in FIG. 12, the luminance distribution near the position along the line II in FIG. 5 will be described.
[0045]
In this embodiment, three different brightness thresholds are set for the same black object (specific image), a portion having a brightness equal to or higher than the threshold is indicated by white, a portion having a brightness lower than the threshold is indicated by black, and the entire gray image is shaded. Can be obtained as three binarized images. Appropriate values are derived in advance for the three luminance thresholds according to the shape of the container, the type of liquid, and the type of foreign matter.
[0046]
The area is calculated for each black object in the image binarized by the first threshold V1. The object (specific image) shown in the enlarged view on the left side in FIG. 12 has the area A1, and the object (specific image) shown in the enlarged view on the right side in FIG. 12 has the area B1. Similarly, the grayscale image is binarized by the second and third threshold values V2 and V3, and the areas A2 and B2 and A3 and B3 are calculated. The average value A of the reduction ratio of A2 to A1 and the reduction ratio of A3 to A2, and the average value B of the reduction ratio of B2 to B1 and the reduction ratio of B3 to B2 are calculated. This is calculated for all black objects, and it is determined whether or not it is a foreign object according to the average area reduction ratio.
[0047]
In the example of FIG. 12, the average area reduction ratio is A = 12% and B = 48%, and the area reduction ratio of 25% or less is determined and extracted as a foreign substance, and the black object corresponding to A can be determined as a foreign substance. . The area reduction ratio is usually determined based on 10% to 30% to determine whether or not the foreign matter exists.
[0048]
In this embodiment, a plurality of binarized images are obtained for the image of the same black object, and since the illumination system is not switched, the processing time can be reduced and the detection accuracy can be improved.
[0049]
FIG. 13 shows a seventh embodiment of the present invention in which a lens is added to enable detection of a foreign substance having a smaller size.
In this embodiment, as shown in FIG. 13, a telecentric optical system 14 capable of mainly capturing only light rays parallel to the lens optical axis with the imaging camera 2 is incorporated.
[0050]
As shown in FIG. 14, the telecentric optical system 14 has an aperture 26 at a focal position 25 of a lens 24, and a light ray 26 along the optical axis of the lens 24 and a light ray 27 parallel to the optical axis of the lens 24 The light beam 28 passing through the focal position 25 but obliquely incident on the optical axis of the lens 24 is blocked by the stop 26 without passing through the focal position 25.
[0051]
As a result, even if the amount of light is increased, the amount of the transmitted illumination light 10 that enters around the outer periphery of the foreign matter and decreases is suppressed, the rise in luminance near the outline of the foreign matter is suppressed, and the imaging camera 2 can capture an image of the same size (FIG. 6). In L2 = L1), even a small foreign matter size can be recognized.
[0052]
In FIG. 14, the lens 24a is installed not only on the object side but also on the image side, and the telecentric optical system 14 is provided on both sides. The light beam after passing through the focal position 25 is also a light beam parallel to the optical axis of the lens 24a, so that even smaller foreign matter sizes can be recognized. However, depending on the required foreign matter size, the incorporation of the lens 24a can be eliminated and only the lens 24 can be used.
[0053]
The detection of precipitated foreign matter has been described above. Next, an eighth embodiment for detecting foreign matter floating on the liquid surface will be described with reference to FIG.
Among the foreign substances 8b floating on the liquid surface in the container 3 in FIG. 5, those existing near the container lid 4 made of an opaque material may not be detected because they are blocked by the container lid 4.
[0054]
In this embodiment, an opening 33a is provided in the transparent acrylic container mounting portion 33, the container 3 is inverted, the illumination light irradiating unit 1 is arranged below the transport conveyor 11, and from the lower side of the inverted container 3 Irradiate. The imaging camera 2a is installed above the inverted container 3 and irradiates with transmission illumination light via the light guide 5 to capture an image as in the first embodiment.
[0055]
In this case, when the shape of the container bottom of the container 3 becomes an obstacle in imaging, the container 3 is imaged in an oblique posture with a smaller angle than the vertical inversion and with less obstacles.
This makes it possible to detect a foreign substance floating on the liquid surface of the container 3 filled with the liquid up to the vicinity of the container lid 4.
[0056]
Next, a ninth embodiment for detecting a foreign substance 8c floating in the liquid in the container 3 of FIG. 5 will be described with reference to FIG.
The foreign matter 8c floating in the middle is too large in distance to the imaging camera, and the foreign matter attached to the inner surface of the container side wall in the intermediate part cannot be detected by the imaging camera in the configuration of FIG. It is difficult to simultaneously image with the imaging camera 2 shown in FIG.
[0057]
Therefore, in this embodiment, in addition to the illumination light irradiator and the imaging camera shown in FIGS. 1 and 15 which are not shown, light from an illumination light source is transmitted via a light guide 5 to the illumination light irradiator (illumination light Means) Irradiate the side of the container 3 from 1b. At this time, one or more light guides 5 are provided according to the width value of the container 3. The imaging camera (imaging means) 2b is arranged on the side surface so as to sandwich the illumination light irradiation unit 1b and the container 3. When the side surface shape of the container 3 causes optical disturbance in image processing, a diffuser (not shown) may be provided between the light guide 5 and the container 3 in order to further increase the scattered light. This makes it possible to detect a foreign substance floating in an intermediate portion in the container 3.
[0058]
Although not shown, a description will be given of the case where the foreign substance detection, the appearance inspection of the container 3 and the liquid level inspection are also performed simultaneously.
The simultaneous inspection may be arbitrarily combined from the three of the foreign substance inspection, the appearance inspection, and the liquid level inspection. Originally provided with the imaging camera 2, it is possible to inspect appearance defects and liquid level abnormalities without adding special parts. The poor appearance corresponds to deformation of the container, abnormal thickness during molding and manufacturing of the container, abnormal shape due to projections, leakage of contents, and the like. The abnormal liquid level corresponds to a liquid level fluctuation due to a liquid capacity defect such as a defective liquid filling, a liquid leak due to breakage of the container 3, and an increase in an apparent volume due to mixing of a large foreign substance into the container 3.
[0059]
In the case where there is a defect in appearance, since the progress of the light of the transmitted illumination light 10 is changed, the dark portion in the image is changed as compared with the normal case, and the inspection device control unit is also used in all the embodiments described above. Even if no special internal processing is performed at 30, the inspection apparatus is discharged from the transport conveyor 11 as if foreign matter was mixed in operation. Further, in order to determine the abnormality of the liquid level, the foreign matter inspection optical system according to the ninth embodiment shown in FIG. 16 is diverted, and the foreign matter extraction data accumulated in the image information storage unit 20 of the main arithmetic unit 19 is handled. Run programmatically. That is, this is determined by calculating the position where the luminance is linearly converted from the relative position with respect to the container 3 because the light absorption amount in the liquid is larger than the light absorption amount in the gas.
[0060]
The image processing in the second and sixth embodiments can be used in the eighth and ninth embodiments, and the illumination light irradiation unit 1 in the third and fourth embodiments is used in the eighth embodiment. be able to.
[0061]
The ring-shaped illumination light irradiating section in FIGS. 2, 9, and 10 may be configured to directly irradiate illumination light from a ring-shaped fluorescent lamp.
[0062]
Although the apparatus for detecting foreign matter in a container has been described above, the present apparatus can be implemented by being incorporated into a container inspection apparatus, and the container in which foreign matter is detected is immediately removed from the production line or marked, and used in a subsequent process. It may be removed.
[0063]
【The invention's effect】
As described above, according to the present invention, it is possible to suppress a difference in brightness in an image due to an uneven distribution of the amount of light generated due to refraction or reflection of light coming from the shape of a container, and to stably remove foreign matter mixed in the container. It can be detected correctly.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an apparatus for detecting foreign matter in a container according to an embodiment of the present invention.
FIG. 2 is a diagram showing an irradiation state of transmitted illumination light in the embodiment of FIG.
FIG. 3 is a diagram showing a block configuration of a detection device control unit in the embodiment of FIG. 1;
FIG. 4 is a diagram showing the presence of foreign matter in a container.
FIG. 5 is a diagram showing an image of a container obtained by the imaging camera in the embodiment of FIG.
FIG. 6 is a diagram showing the luminance of an image at a position along the line II in FIG. 5 according to the method for detecting foreign matter in a container according to the second embodiment of the present invention.
FIG. 7 is a diagram showing a situation of foreign matter by performing image processing on the video of FIG. 5;
8 is a diagram showing a situation of a foreign substance by performing image processing on an image obtained by irradiating a container having obtained the image of FIG. 5 with an amount of illumination light exceeding the sensitivity of an imaging camera and performing image processing.
FIG. 9 is a diagram illustrating a configuration of an illumination light irradiation unit in a foreign object detection device in a container according to a third embodiment of the present invention.
FIG. 10 is a diagram showing a configuration of an illuminating light irradiating unit in a foreign object detection device in a container according to a fourth embodiment of the present invention.
FIG. 11 is a diagram showing a state of foreign matter by performing image processing on an image obtained by an imaging camera according to a foreign matter detection method in a container according to a fifth embodiment of the present invention.
FIG. 12 is a diagram showing the luminance of an image at a position along the line II in FIG. 5 relating to the method for detecting foreign matter in a container according to the sixth embodiment of the present invention.
FIG. 13 is a diagram illustrating a configuration of an illumination light irradiation unit in a foreign object detection device in a container according to a seventh embodiment of the present invention.
FIG. 14 is a diagram showing an illumination light irradiation state in an illumination light irradiation unit shown in FIG.
FIG. 15 is a diagram showing a configuration of a foreign matter detection device in a container according to an eighth embodiment of the present invention.
FIG. 16 is a view showing a configuration of a container foreign matter detection device according to a ninth embodiment of the present invention.
FIG. 17 is a diagram showing a conventional technique.
FIG. 18 is a diagram showing a conventional technique.
[Explanation of symbols]
1, 1a, 1b: illumination light irradiation unit
2, 2a, 2b ... imaging camera
3. Container
3a: Container bottom
4: Container lid
5,5a, 5b ... light guide
6,6a, 6b ... Illumination light source
8, 8a to 8c: Foreign matter
9, 9a ... Foreign matter image
9b: Detected foreign matter in the binarized image
10, 10a, 10b ... transmitted illumination light
11 ... conveyor
12: Foreign matter inspection position
13: Container presence detection sensor
15 ... Imaging camera controller
16 Shutter signal control unit
17… Camera interface
18 ... Image processing monitor
19 ... Main arithmetic unit
20: Image information storage unit
21: Main storage unit
22 ... Monitor
23 ... I / O interface
30 ... Inspection device control unit
31 ... Operation switch
32… Indicator lamp
33 ... Container mounting part

Claims (9)

In a container foreign matter detection device that illuminates a transparent container filled with liquid with illumination light and detects foreign matter in the container from the image of the container obtained by the imaging means,
An apparatus for detecting foreign matter in a container, comprising: illuminating light irradiating means for irradiating illuminating light on the lid side of the container; and imaging means on the bottom side of the container. 2. The apparatus for detecting foreign matter in a container according to claim 1, wherein the illuminating light irradiating means is capable of irradiating an amount of light sufficient to exceed the sensitivity of the imaging device in the imaging means, and has means for controlling the amount of light. Device for detecting foreign matter in a container. 2. The foreign matter detecting device according to claim 1, wherein the illuminating light irradiating means has a ring shape and irradiates the illuminating light from an outer peripheral side of a lid of the container. . 2. The apparatus for detecting foreign matter in a container according to claim 1, wherein the illuminating light irradiating means includes a plurality of irradiating units arranged concentrically and in a ring shape, and has a means for switching blinking of irradiation in each irradiating unit. Device for detecting foreign matter in containers. 2. The apparatus for detecting foreign matter in a container according to claim 1, further comprising an optical unit for aligning light beams from the illumination light irradiation unit to the imaging unit in parallel. 2. The container foreign matter detection device according to claim 1, further comprising: an illumination light side irradiating means for irradiating transmitted illumination light from a side of the container; and the container sandwiched between the illumination light side irradiating means. An apparatus for detecting foreign matter in a container, further comprising an image pickup means for picking up an image on a side of the container. In a container foreign matter detection method of irradiating a transparent container filled with liquid with illumination light and detecting foreign matter in the container from an image of the container obtained by the imaging means,
A first image at an amount of illumination light not exceeding the luminance limit of the imaging means and a second image at an amount of illumination light exceeding the luminance limit at the imaging means are obtained, and an arbitrary threshold set for the second image is obtained. A method for detecting foreign matter in a container, comprising detecting an image of an object having no brightness as a foreign matter. In a container foreign matter detection method of irradiating a transparent container filled with liquid with illumination light and detecting foreign matter in the container from an image of the container obtained by the imaging means,
Obtain a first image at an amount of illumination light not exceeding the luminance limit in the imaging means and a second image at an illumination light amount exceeding the luminance limit in the imaging means, and determine the area reduction rate of the image of the same object in both images. A method for detecting foreign matter in a container, wherein a foreign matter having an area reduction rate equal to or less than an arbitrary area reduction rate is detected. In a container foreign matter detection method of irradiating a transparent container filled with liquid with illumination light and detecting foreign matter in the container from an image of the container obtained by the imaging means,
A plurality of arbitrary thresholds are set with respect to luminance for an image at an amount of illumination light that does not exceed the luminance limit in the imaging means, and an area at each threshold is obtained for an image of the same object, and the area reduction rate of the image is an arbitrary area reduction. A method for detecting foreign matter in a container, comprising detecting foreign matter having a rate equal to or less than the rate.

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