JP6996736B2 - Foreign matter inspection device - Google Patents

Description

The present invention relates to a foreign matter inspection device for photographing the bottom of a translucent container such as a glass bottle and inspecting whether or not there is a foreign matter in the translucent container.

Foreign substances such as metal pieces and glass pieces may be mixed in a glass bottle filled with a liquid such as a beverage. Foreign matter is often settled on the bottom of the glass bottle. Therefore, after filling the glass bottle with a liquid such as a beverage, an inspection is performed to see if foreign matter has settled on the bottom of the glass bottle. As a device for detecting a foreign substance, there is a foreign substance inspection device that detects a foreign substance by image processing (see, for example, Patent Document 1). Specifically, while the glass bottle is being transported by the transport device, the bottom of the glass bottle is imaged with a camera from diagonally below the glass bottle, and foreign matter is detected from the obtained image. Since the foreign matter appears as a white or black shadow on the image, it is possible to detect the presence or absence of the foreign matter by image processing.

Japanese Unexamined Patent Publication No. 2004-317426 Japanese Unexamined Patent Publication No. 2003-107011 Japanese Unexamined Patent Publication No. 2012-42365

The outer surface of the bottom of the glass bottle may usually be embossed or engraved with letters or numbers. Since such embossing and engraving also appear as shadows on the image, the conventional foreign matter inspection device may detect the embossing and engraving as foreign matter. Therefore, in order to accurately detect foreign matter, there is a foreign matter inspection device that detects foreign matter moving in the liquid by stopping the spin of the container after spinning the container filled with the liquid (see Patent Document 2). However, this type of foreign matter inspection device requires a special transport device for spinning the container, and not only the whole foreign matter inspection device becomes large, but also the existing transport device in the factory cannot be used.

As a device for inspecting a container without spinning the container, there is a foreign matter inspection device that illuminates the container from above and receives the transmitted light transmitted through the bottom of the container by an image pickup means arranged below the container to generate an image. (See Patent Document 3). However, even with this device, in order to image the bottom of the container from below, a special transport device for transporting the container while sandwiching both sides of the container is required.

Therefore, the present invention is not affected by embossing or engraving formed on the bottom of a translucent container such as a glass bottle, and accurately removes foreign matter in the translucent container conveyed by an existing transfer device. It is an object of the present invention to provide a foreign matter inspection device capable of detecting.

One aspect of the present invention is a lighting device arranged on the side of a translucent container transported by a transport device and illuminating the translucent container filled with a liquid, and the lighting device sandwiching the transport device. The lighting device includes an image pickup device that generates an image of the bottom of the translucent container and an image processing device that processes the image of the bottom, and the lighting device is a surface lighting device that emits light in multiple directions. When the refractive index of the translucent container is higher than the refractive index of the liquid, the light emitted from the lighting device passes through the first light reflected on the inner surface of the bottom portion and the inside of the bottom portion. When the image pickup device is in a position where it can receive the first light when it advances and is separated into the second light reflected on the outer surface of the bottom portion, the image pickup device advances in the bottom portion and the outer surface thereof. It is a foreign matter inspection apparatus characterized in that the incident angle of the second light reflected by the above into the inner surface is larger than the critical angle and is arranged at a position where the second light does not reach .

A preferred embodiment of the present invention is characterized in that the image pickup device is arranged at a position higher than the inner surface of the bottom of the translucent container on the transfer device.
A preferred embodiment of the present invention is characterized in that the image pickup apparatus includes a reflection mirror arranged at a position capable of receiving the first light.
In a preferred embodiment of the present invention, the image pickup device is a plurality of image pickup devices, the plurality of image pickup devices simultaneously generate an image of the bottom of a plurality of translucent containers, and the image processing device is a plurality of the image processing devices. It is characterized by processing an image of the bottom of a transmissive container.

When the incident angle of the second light traveling toward the liquid in the bottom of the translucent container is larger than the critical angle, the second light is totally reflected by the inner surface of the bottom and the second light is transferred to the liquid. Does not progress. According to the present invention, since the image pickup device does not receive the second light, the image generated by the image pickup device does not show the embossing or marking formed on the outer surface of the bottom. As a result, the foreign matter inspection device can accurately detect foreign matter in the translucent container without being affected by embossing or engraving.

According to the present invention, the image pickup device can be arranged on the side of the translucent container. Therefore, a general type transfer device such as a straight conveyor can be used as the transfer device for transporting the translucent container. Therefore, the foreign matter inspection device of the present invention can inspect the translucent container by using the transport device already installed in the factory as it is.

It is a front view which shows one Embodiment of the foreign matter inspection apparatus of this invention. It is a top view of the foreign matter inspection apparatus shown in FIG. 1. It is a schematic diagram which shows how the diffused light emitted from a lighting device is reflected by the inner surface of the bottom of a glass bottle. It is a figure explaining the position of the image pickup apparatus. It is a figure which shows the state of the traveling of the light when the angle of incidence of the second light on the inner surface of the bottom of a glass bottle is smaller than the critical angle. FIG. 4 is a diagram showing an image generated by an image pickup device arranged at a position where the incident angle of the second light is larger than the critical angle, which is shown in FIG. FIG. 5 is a diagram showing an image generated by an image pickup device arranged at a position where the incident angle of the second light is smaller than the critical angle, which is shown in FIG. It is a figure which shows the other embodiment of the foreign matter inspection apparatus. It is a figure which shows still another embodiment of the foreign matter inspection apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a front view showing an embodiment of the foreign matter inspection device of the present invention, and FIG. 2 is a top view of the foreign matter inspection device shown in FIG. 1. In FIGS. 1 and 2, reference numeral 1 represents a glass bottle which is an example of a translucent container. The foreign matter inspection device of the present embodiment inspects whether or not there is a foreign matter on the bottom 1a of the glass bottle 1 in a state of being filled with a liquid such as a beverage.

The foreign matter inspection device includes a lighting device 3 that illuminates the glass bottle 1 filled with liquid, and an image pickup device 5 that generates an image of the bottom 1a of the glass bottle 1 from the light reflected by the inner surface 1b of the bottom 1a of the glass bottle 1. The image processing device 7 for processing the image generated by the image pickup device 5 is provided. The lighting device 3 and the image pickup device 5 are arranged on both sides of the transport device 10. That is, the lighting device 3 is arranged on the side of the glass bottle 1 transported by the transport device 10, and the image pickup device 5 is arranged so as to face the lighting device 3 with the transport device 10 interposed therebetween. In the present embodiment, the image pickup device 5 is arranged on the side of the transfer device 10 and at a position higher than the transfer surface (mounting surface of the glass bottle 1) 10a of the transfer device 10.

The lighting device 3 is configured to be capable of emitting diffused light, and for example, a light emitting diode is used as a light source of the lighting device 3. The image pickup apparatus 5 includes a camera 5a equipped with an image sensor such as a CCD or CMOS. The lighting device 3 irradiates the bottom 1a of the glass bottle 1 with diffused light, and the image pickup device 5 receives the light reflected from the bottom 1a of the glass bottle 1 by an image sensor to generate an image of the bottom 1a of the glass bottle 1. It is configured in.

In the present embodiment, as shown in FIG. 1, the image pickup device 5 is arranged at a position higher than the inner surface 1b of the bottom portion 1a of the glass bottle 1 on the transfer device 10. More specifically, the camera 5a of the image pickup apparatus 5 is inclined downward toward the inner surface 1b of the bottom portion 1a of the glass bottle 1 on the transport device 10. In one example, the angle of the image pickup device 5 with respect to the inner surface 1b of the bottom 1a of the glass bottle 1 is less than 10 degrees.

The foreign matter inspection device inspects the glass bottle 1 as follows. The glass bottle 1 is conveyed at a predetermined speed by the conveying device 10. As shown in FIG. 2, the conveyor 10 is a linear conveyor and conveys a plurality of glass bottles 1 at regular intervals. While the lighting device 3 illuminates the bottom portion 1a of the glass bottle 1 moved by the transport device 10, the image pickup device 5 receives the light reflected by the inner surface 1b of the bottom portion 1a of the glass bottle 1 and generates an image of the bottom portion 1a. do.

The image processing device 7 receives an image from the image pickup device 5 and executes image analysis. More specifically, the image processing apparatus 7 determines whether or not there is a foreign substance in the bottom portion 1a of the glass bottle 1 based on the image of the bottom portion 1a. Since the foreign matter appears in the image as a white or black shadow, the image processing apparatus 7 can detect the foreign matter based on the image. When a foreign substance is detected in the glass bottle 1, the image processing device 7 may transmit an alarm signal. The image pickup device 5 and the image processing device 7 sequentially inspect a plurality of glass bottles 1 transported by the transfer device 10 in the same manner.

The lighting device 3 is so-called surface lighting, and is configured to emit light in multiple directions from a wide area. FIG. 3 is a schematic view showing how the diffused light emitted from the lighting device 3 is reflected by the inner surface 1b of the bottom portion 1a of the glass bottle 1. As shown in FIG. 3, the inner surface 1b of the bottom portion 1a of the glass bottle 1 generally has a curved shape protruding upward. The diffused light emitted from the illuminating device 3 is incident on the inner surface 1b of the bottom 1a at various angles of incidence and is reflected by the inner surface 1b. The reflected light passes through the side surface 1d of the glass bottle 1, and the image pickup apparatus 5 receives a part of the light reflected by the inner surface 1b of the bottom portion 1a of the glass bottle 1. In the example shown in FIG. 3, the light indicated by the alternate long and short dash line is received by the image pickup apparatus 5, but the light indicated by the dotted line is not received by the image pickup apparatus 5. Therefore, the range irradiated with the light indicated by the alternate long and short dash line is the inspection range.

FIG. 4 is a diagram illustrating the position of the image pickup apparatus 5. The image pickup apparatus 5 is arranged at a position where the following light can be received among the light reflected by the inner surface 1b of the bottom portion 1a of the glass bottle 1. That is, the light emitted from the lighting device 3 is the first light L1 reflected on the inner surface 1b of the bottom 1a of the glass bottle 1, and the second light traveling in the bottom 1a and reflected on the outer surface 1c of the bottom 1a. When divided into L2, the image pickup apparatus 5 is at a position where it can receive the first light L1 reflected by the inner surface 1b of the bottom portion 1a, and is on the inner surface 1b of the second light L2 reflected by the outer surface 1c. The incident angle α is arranged at a position larger than the critical angle. Since the image pickup apparatus 5 arranged at such a position does not receive the second light L2 reflected by the outer surface 1c of the bottom 1a of the glass bottle 1, an image in which the emboss 15 formed on the outer surface 1c does not appear is generated. can do.

It is generally known that when the incident angle of light traveling from a medium having a large refraction index to a medium having a small refraction index is larger than the critical angle, the light is totally reflected at the interface between the media. Since the refractive index of the glass bottle 1 is higher than the refractive index of the liquid in the glass bottle 1, there is a critical angle at the incident angle α of the second light L2 traveling from the bottom 1a of the glass bottle 1 to the liquid. The critical angle is obtained in advance by calculation from the refractive index of the glass bottle 1 and the refractive index of the liquid. When the incident angle α of the second light L2 is larger than the critical angle, as shown in FIG. 4, the second light L2 is totally reflected by the inner surface 1b of the bottom 1a, and the second light L2 travels in the liquid. do not do. Therefore, the second light L2 does not reach the image pickup apparatus 5.

FIG. 5 is a diagram showing a state of light progress when the incident angle α of the second light L2 is smaller than the critical angle. When the incident angle α of the second light L2 is smaller than the critical angle, a part of the second light L2 travels to the liquid from the bottom 1a of the glass bottle 1 and transmits the liquid as shown in FIG. To reach the image pickup device 5. In this case, the emboss 15 appears in the image generated by the image pickup apparatus 5.

FIG. 6 is a diagram showing an image generated by the image pickup apparatus 5 arranged at a position where the incident angle α of the second light L2 is larger than the critical angle shown in FIG. 4, and FIG. 7 is a diagram showing an image generated by FIG. It is a figure which shows the image generated by the image pickup apparatus 5 arranged at the position where the incident angle α of the 2nd light L2 is smaller than a critical angle. The angle of the image pickup device 5 with respect to the inner surface 1b of the bottom 1a of the glass bottle 1 when the image of FIG. 6 is acquired is less than 10 degrees, and the inner surface of the bottom 1a of the glass bottle 1 when the image of FIG. 7 is acquired. The angle of the image pickup device 5 with respect to 1b was about 30 degrees.

As can be seen from FIGS. 6 and 7, the foreign matter 20 and the embossing 15 appear in the image shown in FIG. 7, whereas the foreign matter 20 appears in the image shown in FIG. 6, but the embossing appears. do not have. As described above, the foreign matter inspection device of the present embodiment accurately detects the foreign matter in the glass bottle 1 without being affected by the embossing or engraving formed on the outer surface 1c of the bottom 1a of the glass bottle 1. Can be done.

The image pickup apparatus 5 can be arranged on the side of the glass bottle 1. In the present embodiment, the image pickup device 5 is arranged at a position higher than the inner surface 1b of the bottom portion 1a of the glass bottle 1 on the transfer device 10. As described above, the position and angle of the image pickup apparatus 5 are not particularly limited as long as the condition that the first light L1 can be received and the incident angle α of the second light L2 is larger than the critical angle is satisfied. .. Therefore, a general type transfer device such as a straight conveyor can be used for the transfer device 10 for transporting the glass bottle 1. Therefore, the foreign matter inspection device of the present embodiment can inspect the glass bottle by using the transport device already installed in the factory as it is.

FIG. 8 is a diagram showing another embodiment of the foreign matter inspection device. Since the configuration and operation of the present embodiment not particularly described are the same as those of the embodiments shown in FIGS. 1 and 2, the duplicated description thereof will be omitted. In the embodiment shown in FIG. 8, the image pickup device 5 includes a reflection mirror 5b arranged between the camera 5a and the transfer device 10. The light reflected by the inner surface 1b of the bottom 1a of the glass bottle 1 is further reflected by the reflection mirror 5b and reaches the camera 5a. The camera 5a is arranged above the reflection mirror 5b.

Also in this embodiment, the reflection mirror 5b of the image pickup apparatus 5 is arranged at the same position as the image pickup apparatus 5 shown in FIG. That is, the reflection mirror 5b is at a position where the first light L1 reflected by the inner surface 1b of the bottom portion 1a of the glass bottle 1 can be received, and the second light L2 reflected by the outer surface 1c is directed to the inner surface 1b. The incident angle α is arranged at a position larger than the critical angle. Therefore, the foreign matter inspection device of the present embodiment can accurately detect foreign matter in the glass bottle 1 without being affected by embossing or engraving formed on the outer surface 1c of the bottom 1a of the glass bottle 1. .. Further, since the camera 5a can receive the first light L1 through the reflection mirror 5b, the degree of freedom in the installation position of the camera 5a is increased. In one embodiment, the camera 5a may be located below the reflection mirror 5b.

FIG. 9 is a diagram showing still another embodiment of the foreign matter inspection device. Since the configuration and operation of the present embodiment not particularly described are the same as those of the embodiments shown in FIGS. 1 and 2, the duplicated description thereof will be omitted. In the embodiment shown in FIG. 9, a plurality of image pickup devices 5, 22, 23 are provided. These image pickup devices 5, 22 and 23 are arranged on the side opposite to the lighting device 3 with the transport device 10 interposed therebetween, and all face the lighting device 3. Similar to the image pickup device 5, the image pickup devices 22 and 23 are at positions and angles that satisfy the condition that the first light L1 can be received and the incident angle α of the second light L2 is larger than the critical angle. Have been placed. The image processing device 7 is connected to the image pickup devices 5, 22 and 23, and is configured to process the images sent from these image pickup devices 5, 22 and 23 to detect foreign matter in the glass bottle 1. Has been done.

In the present embodiment, in addition to the image pickup device 5 shown in FIG. 2, two image pickup devices 22 and 23 are arranged on both sides of the image pickup device 5, but more image pickup devices may be provided. The foreign matter inspection device according to the present embodiment can inspect a plurality of glass bottles 1 at the same time, and the throughput is improved. The reflection mirror 5b shown in FIG. 8 can also be applied to the embodiment of FIG.

The above-described embodiments have been described for the purpose of allowing a person having ordinary knowledge in the technical field to which the present invention belongs to carry out the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Accordingly, the invention is not limited to the described embodiments, but is to be construed in the broadest range in accordance with the technical ideas defined by the claims.

1 Glass bottle 3 Lighting device 5 Image pickup device 5a Camera 5b Reflection mirror 7 Image processing device 10 Conveyor device 15 Embossed 20 Foreign matter 22, 23 Image pickup device L1 First light L2 Second light

Claims (4)

A lighting device arranged on the side of the translucent container transported by the transport device and illuminating the translucent container filled with a liquid.
An image pickup device that is arranged so as to face the lighting device with the transport device in between and generates an image of the bottom of the translucent container.
An image processing device for processing the bottom image is provided.
The lighting device is a surface lighting device that emits light in multiple directions.
When the refractive index of the translucent container is higher than the refractive index of the liquid, the light emitted from the lighting device travels in the bottom portion with the first light reflected on the inner surface of the bottom portion. When separated into the second light reflected on the outer surface of the bottom, the image pickup apparatus is at a position where the first light can be received, and travels inside the bottom and is reflected on the outer surface. A foreign matter inspection device characterized in that the incident angle of the second light on the inner surface is larger than the critical angle and the second light is arranged at a position where the second light does not reach . The foreign matter inspection device according to claim 1, wherein the image pickup device is arranged at a position higher than the inner surface of the bottom of the translucent container on the transfer device. The foreign matter inspection device according to claim 1, wherein the image pickup device includes a reflection mirror arranged at a position capable of receiving the first light. The image pickup device is a plurality of image pickup devices.
The plurality of image pickup devices simultaneously generate images of the bottoms of a plurality of translucent containers.
The foreign matter inspection device according to any one of claims 1 to 3, wherein the image processing device processes an image of the bottom of the plurality of transparent containers.

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