JP2015219090A - Transmission inspection device - Google Patents

Abstract

Provided is a transmission inspection apparatus capable of taking a transmission image of an object to be measured without being affected by ambient light and performing a transmission inspection of the object to be measured based on the transmission image.
A transmission inspection apparatus for performing a transmission inspection of an object to be measured, the mounting means on which the object to be measured is placed, and a plurality of light projecting means for irradiating the object to be measured with inspection light And an image photographing means for photographing an image of the article to be measured. The plurality of light projecting means and the image photographing means are arranged at positions facing each other with the placing means interposed therebetween, and the plurality of light projecting means. And the optical axis of the image photographing means are arranged so that they do not coincide with each other, and the image photographing means performs a transmission inspection of the measurement object by photographing a transmission image based on the inspection light transmitted through the measurement object. .
[Selection] Figure 1

Description

  The present invention relates to a transmission inspection apparatus capable of performing non-destructive internal inspection of an article to be measured, such as detection of foreign matters mixed in food and detection of presence / absence, position, and size of ingredients contained in food. .

  Conventionally, in food production processes, foreign substances such as stones, metals, insects, hair, etc. may be mixed inside the food. In order to remove it, the inside of food is inspected nondestructively.

FIG. 9 is a schematic configuration diagram for explaining the configuration of a foreign matter inspection apparatus used for conventional inspection of food inside.
As shown in FIG. 9, the foreign matter inspection apparatus 100 includes a transparent tray 102 for placing a measurement target food 112 that is a measurement target, and a light projecting unit 104 that irradiates the measurement target food 112 with inspection light 106. And an imaging means 110 for capturing an image based on the inspection light (transmitted light 108) transmitted through the food under test 112.

  In the foreign substance inspection apparatus 100 configured as described above, a film camera, a digital camera, or the like is photographed while the inspection light 106 that passes through the food to be measured 112 such as near infrared light is irradiated from below the food to be measured 112. The food to be measured 112 is photographed by the means 110.

  Thus, the presence or absence of the foreign material mixed in the to-be-measured food 112 can be confirmed by confirming the picked-up image which image | photographed to-be-measured food 112 visually or with the analyzer which is not shown in figure.

  However, in such a foreign matter inspection apparatus 100, inspection light (direct light 114) that directly enters the imaging means 110 from the outside of the food to be measured 112 or inspection light (disturbance light) that leaks from the outside of the food to be measured 112 is received. It becomes a problem. Since the direct light 114 and the disturbance light have a larger light amount than the transmitted light 108, when the direct light 114 or the disturbance light is incident on the imaging unit 110 that is set to capture an image based on the transmitted light 108, the imaging unit 110. Exceeds the allowable light quantity range.

  In particular, when a food having a low transmittance, such as chocolate, is inspected as the food to be measured 112, the photographing means 110 is set in accordance with the transmitted light 108 having a small amount of light that can be received. 114 and disturbance light.

  As a result, when a digital camera is used as the photographing means 110, a blooming phenomenon due to leakage of signals between the image sensors occurs, and the photographing image quality is greatly deteriorated.

  Further, when a film camera is used as the photographing unit 110, overexposure occurs, and a phenomenon called overexposure occurs, so that the photographing image quality is greatly deteriorated.

  In order to prevent such a phenomenon, the irradiation range of the inspection light 106 emitted from the light projecting means 104 is reduced, or the food to be measured 112 is placed between the light projecting means 104 and the transparent tray 102 as shown in FIG. The direct light 114 and disturbance light are suppressed by providing a light shielding member 116 so that the inspection light does not leak from the outside.

JP 2009-115613 A JP 2005-233724 A

  However, in the case of suppressing the direct light 114 and disturbance light in this way, the irradiation range of the inspection light 106 may be too small to be sufficiently inspected, or may be shielded according to the shape of the food to be measured 112. It was necessary to change the shape of the member 116.

  Moreover, when inspecting a plurality of foods to be measured 112 during the conveyance of the conveyor, it is necessary to convey the food to be measured 112 so that the food to be measured 112 is positioned on the opening 116a of the light shielding member 116 as shown in FIG. As shown in FIG. 11B, if the position of the food to be measured 112 is shifted, the direct light 114 is incident on the imaging means 110, and an accurate foreign object inspection cannot be performed. There are also problems such as difficulty in operation of food inspection due to the low degree of freedom of the placement position.

  In addition, X-ray inspection devices and metal foreign matter inspection devices are also used as foreign matter inspection devices, but it has been difficult to detect animal-derived foreign matters such as insects and hair.

  In the present invention, in view of such a current situation, it is possible to take a transmission image of the article to be measured without being affected by direct light or disturbance light, and to perform a transmission inspection of the article to be measured based on the transmission image. An object is to provide a transmission inspection apparatus.

The present invention was invented to solve the problems in the prior art as described above, and the internal detection device of the present invention is a transmission inspection device for performing a transmission inspection of an article to be measured,
A placing means on which the article to be measured is placed;
A plurality of light projecting means for irradiating the measurement object with inspection light;
Image photographing means for photographing an image of the article to be measured,
The plurality of light projecting means and the image photographing means are arranged at positions facing each other with the placing means interposed therebetween,
Arranged so that the optical axes of the plurality of light projecting means and the optical axis of the image photographing means do not coincide,
A transmission image based on the inspection light transmitted through the article to be measured is captured by the image capturing means.

In this case, the plurality of light projecting means and the image photographing means are respectively arranged above and below the placing means,
It is preferable that the placing means is capable of transmitting the inspection light.

  Further, background light projecting means capable of irradiating background light having a light amount lower than that of the inspection light at a position on the optical axis of the image photographing means and facing the image photographing means with the article to be measured interposed therebetween. Can be provided.

In the transmission inspection apparatus according to the present invention, the placing means may include a transport means for transporting the article to be measured.
In this case, the placing means includes a tray on which the article to be measured is placed, and the transport means on which the tray is placed,
The tray is configured to transmit the inspection light;
The conveying means may be a belt conveyor provided with two belts spaced apart by a predetermined interval.

Further, the placing means may be a belt conveyor provided with a belt capable of transmitting the inspection light.
In the transmission inspection apparatus according to the aspect of the invention, it is preferable that each of the plurality of light projecting units includes an irradiation range adjusting unit that adjusts an irradiation range of the inspection light.

The transmission inspection apparatus described above further includes an analysis unit that analyzes the image captured by the image capturing unit,
The transmission image can be configured to be inspected by analyzing the transmission image by the analyzing means.

In addition, it further comprises an outer shape image photographing means for photographing an outer shape image for detecting the outer shape of the article to be measured,
The transmission inspection of the article to be measured can be performed by comparing the transmission image captured by the image capturing unit with the contour image captured by the contour image capturing unit.
In this case, the outline image photographing means may include a neutral density filter.

Further, the placing means may be configured to be able to scatter a part of the inspection light.
In this case, the image photographing unit can photograph an outer shape image for detecting the outer shape of the article to be measured.
The transmission inspection of the article to be measured can be performed by comparing the transmission image captured by the image capturing unit with the contour image captured by the contour image capturing unit.

  According to the present invention, a transmission image can be taken without being affected by disturbance light leaking from the outside of the article to be measured, so that high-resolution photography can be performed by increasing the amount of inspection light. For example, hair can be detected reliably.

  Furthermore, as the amount of transmitted light increases, the imaging speed can be increased by the image capturing means, and high-speed transport is possible even when the object to be measured is inspected during continuous transport using the transport means. Thus, the inspection processing speed can be improved.

FIG. 1 is a schematic configuration diagram for explaining a configuration of a transmission inspection apparatus according to the present embodiment. FIG. 2 is a schematic perspective view of the transmission inspection apparatus of FIG. FIG. 3 is a schematic perspective view for explaining a configuration when a plurality of articles to be measured are inspected in the transmission inspection apparatus of FIG. 1. FIG. 4 is a schematic perspective view for explaining another configuration using a conveying means in the transmission inspection apparatus of FIG. FIG. 5 is a schematic configuration diagram for explaining another configuration of the transmission inspection apparatus in FIG. 1. FIG. 6 is a schematic configuration diagram for explaining the configuration of a transmission inspection apparatus according to another embodiment. FIG. 7 is a schematic configuration diagram for explaining the configuration of a transmission inspection apparatus in still another embodiment. FIG. 8 is a photograph showing an example of a photographed image in the case where foreign matter detection of chocolate is performed as an article to be measured using the transmission inspection apparatus shown in FIGS. FIG. 9 is a schematic configuration diagram for explaining the configuration of a foreign matter inspection apparatus used for conventional inspection of food inside. FIG. 10 is a schematic configuration diagram for explaining another configuration of the foreign matter inspection apparatus used for the inspection of the inside of a conventional food product. FIG. 11 is a schematic diagram for explaining the influence of disturbance light during inspection using the foreign substance inspection apparatus of FIG.

Hereinafter, embodiments (examples) of the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram for explaining the configuration of a transmission inspection apparatus according to the present embodiment, and FIG. 2 is a schematic perspective view of the transmission inspection apparatus of FIG.
As shown in FIGS. 1 and 2, the transmission inspection apparatus 10 includes a tray 12 that is a placement unit on which a measurement target 24 that is a measurement target is placed, and a transport unit 30 that transports the tray 12 in the X direction. And a plurality of light projecting means 14a and 14b that irradiate the measurement object 24 with the inspection light 16 and an image photographing means 21 that captures an image of the measurement object 24. And a transmission image photographing means 20 for photographing an image based on the transmission light 18).

  The tray 12 is not particularly limited as long as it has a shape on which the article to be measured 24 can be placed and can transmit the inspection light 16. As long as the inspection light 16 can be transmitted, it may be transparent or semi-transparent.

  In the transmission inspection apparatus 10 shown in FIGS. 1 and 2, the light projecting means 14 constituted by an LED array is used as the light projecting means.

  Further, in the present embodiment, the inspection is performed while the article to be measured 24 is conveyed by the conveying means 30, but the tray 12 is fixed to a fixed base (not shown) in order to inspect the articles to be measured 24 one by one. It may be.

  Further, as shown in FIG. 3, in order to sequentially inspect a plurality of measured articles 24, a plurality of measured articles 24 are placed on the tray 12, and the tray 12 is placed on a conveying means 30 such as a conveyor. It may be.

  In order to prevent the inspection light 16 from being blocked by the conveying unit 30, the conveying unit 30 includes, for example, two belts 32a and 32b arranged at a predetermined interval as shown in FIG. A belt conveyor or a belt conveyor including a transparent or translucent belt 32c as shown in FIG.

  As shown in FIG. 4, when the conveying means 30 is a belt conveyor provided with a transparent or translucent belt 32c, the transparent or translucent belt 32c is used as a placing means without using the tray 12. The measurement article 24 may be placed directly on the transparent or translucent belt 32c.

  The light projecting means 14 a and 14 b can use, for example, a light source capable of irradiating near-infrared light, X-rays, or the like as the light that passes through the measurement object 24 as the inspection light 16. In particular, it is preferable to use a light source capable of irradiating light having a wavelength of 400 to 1700 nm, and it is particularly preferable to use a light source capable of irradiating near infrared light having a wavelength of 700 to 1700 nm. Examples of such a light source include a halogen lamp, a xenon lamp, and an LED (Light Emitted Diode) lamp.

  The transmission image photographing unit 20 is not particularly limited as long as it is a photographing unit capable of photographing an image based on the inspection light transmitted through the article to be measured 24. For example, a digital camera or a film camera may be used. it can.

  The transmission image photographing means 20 is arranged so as to photograph the article to be measured 24 from above in the vertical direction. Further, the optical axes of the light projecting units 14a and 14b and the optical axis of the transmission image photographing unit 20 are arranged so as not to coincide with each other.

  By arranging the transmission image photographing unit 20 and the light projecting units 14a and 14b in this way, the direct light 26 is transmitted from the outside of the article to be measured 24 to the transmitted image among the inspection light 16 irradiated from the light projecting units 14a and 14b. It can be prevented from directly entering the imaging means 20.

  The light projecting units 14a and 14b preferably include an irradiation range adjusting unit 15 including, for example, a condensing lens 15a and a diffusion plate 15b in order to irradiate the measurement object 24 with the inspection light 16 efficiently. .

  Thus, by adjusting the irradiation range of the inspection light 16 by the irradiation range adjusting means 15, the inspection light 16 suitable for the shape of the article to be measured 24 can be irradiated, and direct light is transmitted to the transmission image photographing means 20. 26 can be prevented from entering.

  In the transmission inspection apparatus 10 configured as described above, the amount of the inspection light 16 irradiated from the light projecting units 14a and 14b is also used, for example, when inspecting the measurement object 24 having a low transmittance such as chocolate. Therefore, a high-quality transmission image can be taken.

  Further, by increasing the amount of the inspection light 16 emitted from the light projecting means 14a, 14b, high-resolution imaging with a spatial resolution of about 0.1 mm can be performed, and detection of hair and the like mixed into the measurement object 24 can be performed. You can also

  Furthermore, the increase in the amount of transmitted light 18 can increase the photographing speed of the transmission image photographing means 20, and for example, inspect the measurement object 24 during continuous conveyance using a conveyance means such as a conveyor. Even when it is performed, high-speed conveyance is possible, and the inspection processing speed of the article to be measured 24 can be improved.

  A transmission inspection of the article to be measured 24 such as an inspection of foreign matter mixed inside the article to be measured 24 can be performed by visually confirming the transmission image taken in this way or by analyzing the image by an analysis means 28 such as a computer. It can be carried out.

In addition, in the transmission inspection apparatus 10 of the present embodiment, it is preferable that the image photographing unit 21 includes an outer shape image photographing unit 22 for photographing an image for detecting the outer shape of the article 24 to be measured.
The outer shape image photographing means 22 is not particularly limited as long as it is a photographing means capable of photographing an image capable of specifying the shape of the article 24 to be measured. For example, a digital camera or a film camera is used. Can do.

  Further, it is preferable that the outline image photographing means 22 includes a neutral density filter 23 in order to suppress the influence of the direct light 26. In this way, by providing the neutral density filter 23, the amount of the inspection light 16 irradiated from the light projecting means 14a and 14b can be increased, and even if the article to be measured 24 has a low transmittance, a transmission image is taken. A transmission image can be taken by means 20 and an outline image can be taken by outline image photographing means 22.

  The transmission image photographing unit 20 needs to be an imaging unit capable of detecting the inspection light 16 irradiated by the light projecting units 14a and 14b in order to photograph an image based on the transmitted light 18. It suffices that the object 22 can be photographed by the ambient light.

  In the present embodiment, the outer shape image photographing means 22 is arranged on the optical axis of the light projecting means 14a, 14b so that the outer shape image is photographed by the direct light 26 of the inspection light 16. By doing so, an outline image can be taken even when the transmission inspection apparatus 10 is arranged in a dark space that is not affected by ambient light.

  In this way, by comparing the external image captured by the external image capturing means 22 and the transparent image captured by the transparent image capturing means 20 with the naked eye or by the analyzing means 28, the article to be measured 24 in the transparent image is measured. It is possible to accurately specify the measurement area.

  By specifying the measurement area of the transmission image, it is possible to reliably determine whether the foreign matter is mixed inside the article to be measured 24 or the foreign matter attached to the tray 12, and an accurate inspection can be performed.

  Further, by specifying the measurement region, it is possible to clearly determine where the foreign matter is mixed in the measurement object 24. In addition, by the same method, not only contamination of foreign matter but also the inside of the article to be measured 24 can be inspected.

  Specifically, the presence or absence of the ingredients, the position, the size, etc. can be detected by making the food to be measured 24 a food in which ingredients are put inside, such as a bun, daifuku, and bread. It can also be used for quality inspection.

  The “foreign matter” and “material” that can be detected by the transmission inspection apparatus 10 of the present embodiment are not particularly limited as long as the absorbance of the inspection light 16 is different from that of the measurement object 24. .

  Further, in this embodiment, the transmission image photographing means 20 and the outer shape image photographing means 22 are arranged above the tray 12 and the light projecting means 14a and 14b are arranged below the tray 12, as shown in FIG. As described above, the transmission image photographing unit 20 and the outer shape image photographing unit 22 may be disposed below the tray 12, and the light projecting units 14 a and 14 b may be disposed above the tray 12. That is, the inspection light 16 irradiated from the light projecting means 14a and 14b may be transmitted through the article to be measured 24 and incident on the transmission image photographing means 20, and the light projecting means 14a and 14b and the transmission image photographing means 20 are provided. What is necessary is just to arrange | position in the position which opposes on both sides of the tray 12.

  When the light projecting means 14a and 14b and the transmission image photographing means 20 are respectively arranged on the sides of the tray 12, the inspection light 16 cannot be transmitted through the tray 12 as long as the image photographing is not affected. You may comprise.

FIG. 6 is a schematic configuration diagram for explaining the configuration of a transmission inspection apparatus according to another embodiment.
Since the transmission inspection apparatus 10 of this embodiment has basically the same configuration as the transmission inspection apparatus 10 shown in FIGS. 1 to 5, the same members are denoted by the same reference numerals, and detailed description thereof will be given. Omitted.

  In the transmission inspection apparatus 10 of this embodiment, a translucent tray 13 that can scatter a part of the inspection light 16 is used as the mounting means. As a result, the scattered light 27 of the inspection light 16 enters the image capturing means 21 disposed above the article to be measured 24 in the vertical direction.

  Since the scattered light 27 has a smaller amount of light than the direct light 26, even the image photographing means 21 set in accordance with the transmitted light 18 of the article to be measured 24 can capture a transmission image without affecting the image quality. It can be performed.

In addition, when the scattered light 27 is incident on the image capturing means 21, it is possible to capture an outer shape image of the article to be measured 24 using the scattered light 27.
That is, in the transmission inspection apparatus 10 shown in FIGS. 1 to 5, two imaging means, that is, the transmission image imaging means 20 and the outer shape image imaging means 22 are required as the image imaging means. In the transmission inspection apparatus 10 of this embodiment, The image photographing means 21 need only have one photographing means.

FIG. 7 is a schematic configuration diagram for explaining the configuration of a transmission inspection apparatus in still another embodiment.
Since the transmission inspection apparatus 10 of this embodiment has basically the same configuration as the transmission inspection apparatus 10 shown in FIGS. 1 to 6, the same members are denoted by the same reference numerals, and detailed description thereof will be given. Omitted.

In this embodiment, background light projecting means 34 for irradiating background light 36 for photographing the outer shape of the article 24 to be measured is provided on the optical axis of the image photographing means 21.
The background light projecting means 34 only needs to be able to irradiate the background light 36 having a light quantity lower than that of the inspection light 16. Specifically, even if the background light 36 directly enters the image photographing means 21, blooming is performed. Any light source can be used as long as the phenomenon does not occur and the amount of light that can be transmitted through the measurement object 24 can be irradiated.

  Further, by making it possible to adjust the light quantity of the background light projector 34 independently of the projectors 14a and 14b, it is possible to suppress a decrease in resolution and contrast, and to improve both the transmission image and the outline image with high image quality. You can shoot.

  Further, the background light 36 should have low directivity in order to capture the outer shape of the article 24 to be measured. For example, when a light source having high directivity such as an LED is used as the background light projecting means 34, FIG. As shown, it is preferable to provide a diffusion plate 38 for diffusing the background light 36.

  As mentioned above, although the preferable Example of this invention was described, this invention is not limited to this, In the said Example, although the case where it was a foodstuff as the measured article 24 was demonstrated as an example, the measured article 24 For example, it can be used for permeation inspection of tablets, capsules, films, granular powders, papers, cloth-like fibers, etc., without limiting to the object of the present invention. Various changes are possible.

[Example 1]
An example in which foreign matter detection of chocolate is performed as the article to be measured 24 using the transmission inspection apparatus 10 shown in FIG.
FIG. 8A is a photograph of an outer shape image of chocolate that is the article to be measured 24, FIG. 8B is a photograph of a transmission image of chocolate in FIG. 8A, and FIG. It is the photograph which image-processed in order to make the transparent image of b) easy to understand.

  It can be seen that the hair, which is a foreign object 25 that cannot be identified in the outer shape image shown in FIG. 8A, is visible in the transmission images shown in FIGS. 8B and 8C.

DESCRIPTION OF SYMBOLS 10 Transmission inspection apparatus 12 Tray 13 Translucent tray 14 Light projection means 14a Light projection means 14b Light projection means 15 Irradiation range adjustment means 15a Condensing lens 15b Diffuser plate 16 Inspection light 18 Transmitted light 20 Transmission image photographing means 21 Image photographing means 22 Outline image photographing means 23 Neutralizing filter 24 Article 25 to be measured 25 Foreign object 26 Direct light 27 Scattered light 28 Analyzing means 30 Conveying means 32a Belt 32b Belt 32c Belt 34 Background light projecting means 36 Background light 100 Foreign object inspection device 102 Transparent tray 104 Light means 106 Inspection light 108 Transmitted light 110 Imaging means 112 Food to be measured 114 Ambient light 116 Light blocking member 116a Opening

Claims (12)

A transmission inspection apparatus for performing a transmission inspection of an object to be measured,
A placing means on which the article to be measured is placed;
A plurality of light projecting means for irradiating the measurement object with inspection light;
Image photographing means for photographing an image of the article to be measured;
With
The plurality of light projecting means and the image photographing means are arranged at positions facing each other with the placing means interposed therebetween,
Arranged so that the optical axes of the plurality of light projecting means and the optical axis of the image photographing means do not coincide,
A transmission inspection apparatus that captures a transmission image based on inspection light transmitted through the article to be measured by the image capturing means. The plurality of light projecting means and the image photographing means are respectively disposed above and below the placing means,
The transmission inspection apparatus according to claim 1, wherein the placement unit is capable of transmitting the inspection light.   A background light projecting unit capable of irradiating background light having a light amount lower than that of the inspection light is provided on a position on the optical axis of the image capturing unit and facing the image capturing unit with the measurement object interposed therebetween. The transmission inspection apparatus according to claim 1 or 2.   The transmission inspection apparatus according to any one of claims 1 to 3, wherein the placement unit includes a transport unit for transporting the article to be measured. The placing means includes a tray on which the article to be measured is placed, and the transport means on which the tray is placed,
The tray is configured to transmit the inspection light;
The transmission inspection apparatus according to claim 4, wherein the transport unit is a belt conveyor including two belts arranged at a predetermined interval.   The transmission inspection apparatus according to claim 5, wherein the placing means is a belt conveyor including a belt capable of transmitting the inspection light.   The transmission inspection apparatus according to any one of claims 1 to 6, wherein each of the plurality of light projecting units includes an irradiation range adjusting unit that adjusts an irradiation range of the inspection light. An analysis unit for analyzing an image captured by the image capturing unit;
The transmission inspection apparatus according to any one of claims 1 to 7, wherein the transmission inspection of the article to be measured is performed by image analysis of the transmission image by the analysis unit. An external image photographing means for photographing an external image for detecting the external shape of the article to be measured;
The transmission inspection of the article to be measured is performed by comparing the transmission image photographed by the image photographing means and the contour image photographed by the contour image photographing means by the analyzing means. Item 9. The transmission inspection device according to Item 8.   The transmission inspection apparatus according to claim 9, wherein the outline image photographing unit includes a neutral density filter.   The transmission inspection apparatus according to claim 8, wherein the placement unit is configured to be able to scatter a part of the inspection light. The image photographing means can photograph an outer shape image for detecting the outer shape of the article to be measured;
The transmission inspection of the article to be measured is performed by comparing the transmission image photographed by the image photographing means and the contour image photographed by the contour image photographing means by the analyzing means. Item 12. The transmission inspection device according to Item 11.