JP2021028640A - Visual inspection method and surface inspection device - Google Patents

Abstract

To provide a surface inspection device capable of inspecting a tablet that does not fall within an inspection range without causing an increase in costs and a reduction in inspection efficiency.SOLUTION: Imaging means of a first visual inspection device switches to a mode of imaging light or reflecting light from a front surface a plurality of times with a time difference according to a length of a tablet in a moving direction for the tablet whose length in the moving direction exceeds an inspection range. Processing means of the first visual inspection device switches to a mode of combining a plurality of video signals on a front side from the imaging means for the tablet whose length in the moving direction exceeds the inspection range. Imaging means of a second visual inspection device switches to a mode of imaging light or reflecting light from a back surface a plurality of times with a time difference according to a length of the tablet in a moving direction for the tablet whose length in the moving direction exceeds the inspection range. Processing means of the second visual inspection device switches to a mode of combining a plurality of video signals on a back surface side from the imaging means for the tablet whose length in the moving direction exceeds the inspection range.SELECTED DRAWING: Figure 5

Description

The present invention relates to a visual inspection method and a surface inspection apparatus.

Conventionally, visual inspection has been performed to inspect whether or not an article such as a tablet, a candy, or a chocolate has a foreign substance attached or dirty, a deformation such as a chip or a crack, or a defect such as a printing defect.

As an inspection device used for visual inspection of an article, the reflected light from the article to be inspected obtained by irradiating the article to be inspected being transported with light is incident on an imaging means to obtain an image. There are inspection devices that inspect the appearance by processing video signals.

For example, Patent Document 1 describes a reflecting means for reflecting light reflected from a side surface of an article to be inspected, an illuminating means, and an imaging means for capturing light emitted from the reflecting means and reflected light from the upper surface of the article to be inspected. And a processing means for processing a video signal from the imaging means, and the reflecting means includes a plurality of reflectors arranged so as to surround the object to be inspected when viewed from the upper surface side of the article to be inspected. A visual inspection apparatus is disclosed in which the lighting means includes a top lighting means for illuminating at least the upper surface of the article to be inspected from between adjacent reflectors.

The visual inspection apparatus described in Patent Document 1 can simultaneously image and inspect the upper surface and the side surface of the article to be inspected, obtain sufficient intensity of light irradiating the upper surface of the article to be inspected, and obtain sufficient intensity of light to irradiate the upper surface of the article to be inspected. Can be inspected with high accuracy. Further, the technique described in Patent Document 1 has an advantage that it is easier to support a side surface inspection on the traveling side in the transport direction as compared with an inspection using a line sensor camera.

Japanese Unexamined Patent Publication No. 2009-031247

However, the above-mentioned prior art has the following problems.
When the inspection range is set for a circular object to be inspected, a large inspection range is used to inspect a non-circular irregularly shaped article to be inspected, for example, an oval inspected article that does not fit within the inspection range. It is necessary to prepare another optical system for setting the above, which causes problems such as cost increase, installation space increase, replacement work becomes complicated, and inspection efficiency decreases.

The present invention has been made in consideration of the above points, and provides a visual inspection method and a surface inspection apparatus capable of inspecting an article to be inspected that does not fall within the inspection range without causing an increase in cost and a decrease in inspection efficiency. The purpose is to provide.

According to the first aspect of the present invention, the tablet is rotated while holding the back surface opposite to the front surface on the outer peripheral surface in the thickness direction with the surface in the thickness direction facing outward. The first inspection drum that conveys the tablet and the outer peripheral surface are rotatably installed under the first inspection drum so as to be close to each other. The tablet is received from the first inspection drum and the tablet is delivered to the first inspection drum. Appearance of the second inspection drum, which rotates while holding the front surface on the outer peripheral surface in a state where the back surface of the inspection drum is reversed from the conveyed state of the inspection drum, and the tablet held on the outer peripheral surface of the first inspection drum. A first visual inspection device for inspecting the appearance of the tablet and a second visual inspection device for inspecting the appearance of the tablet held on the outer peripheral surface of the second inspection drum are provided, and the first visual inspection device and the first visual inspection device are provided. (2) The visual inspection device targets the tablet moving in the inspection range, and illuminates the tablet in the inspection range, a reflecting means for reflecting reflected light from the side surface of the tablet, and an upper surface of the tablet. It is provided with one imaging means for simultaneously capturing the light emitted from the reflecting means and the reflected light from the upper surface of the tablet, and a processing means for processing the video signal from the imaging means. The reflecting means includes a plurality of reflectors arranged so as to surround the inspection range when viewed from the upper surface side of the tablet, and the imaging means of the first visual inspection apparatus has a length in the moving direction. For the tablet that fits within the inspection range, the light and the reflected light from the surface are imaged once, and for the tablet whose length in the moving direction exceeds the inspection range, in the moving direction. The light and the reflected light from the surface are switched to be imaged a plurality of times with a time difference according to the length of the tablet, and the processing means of the first visual inspection apparatus has a length in the moving direction as the inspection range. For the tablet that fits inside, one video signal on the surface side from the imaging means is processed, and for the tablet whose length in the moving direction exceeds the inspection range, the imaging means The image pickup means of the second visual inspection apparatus switches the plurality of video signals on the front surface side of the tablet so as to combine and processes the light for the tablet whose length in the moving direction falls within the inspection range. And the reflected light from the back surface is imaged once, and for the tablet whose length in the moving direction exceeds the inspection range, the light and the back surface are separated by a time difference according to the length of the tablet in the moving direction. Switching to image the reflected light from the above multiple times, the second The processing means of the visual inspection apparatus processes a single video signal on the back surface side from the imaging means for the tablet whose length in the moving direction falls within the inspection range, and the length in the moving direction. For the tablet whose length exceeds the inspection range, a surface inspection apparatus is provided, which is switched so as to combine and process a plurality of video signals on the back surface side from the imaging means.

Further, in the surface inspection apparatus according to one aspect of the present invention, the imaging means is used for the nth time (n is a positive integer) and (n + 1) for the tablet whose length in the moving direction exceeds the inspection range. The image taken at the first time is characterized in that the image is taken at the timing when a part of the tablet overlaps.

Further, in the surface inspection apparatus according to one aspect of the present invention, the reflector is located outside the intrinsic reflection region and the intrinsic reflection region that reflects the reflected light that is not reflected by another reflector. It has an overlapping reflective region that reflects reflected light that is arranged and reflected by another adjacent reflector, and from the light emitted from the reflecting means, the side surface of the tablet corresponds to the number of reflectors. The image signal divided into the number of the tablets is obtained, and the overlap reflection region reflects the reflected light from the divided portion of the tablet in the divided image signal.

Further, in the surface inspection apparatus according to one aspect of the present invention, the image of the tablet obtained from the image pickup signal processed by the processing means is formed around the image of the upper surface of the tablet and the image of the upper surface. It is characterized by having an image of the side surface of the tablet arranged in a ring shape in a number corresponding to the number of reflectors and the number of times the imaging means has been imaged.

According to the second aspect of the present invention, it is an appearance inspection method for an inspection target of a tablet whose inspection range is moved by using the surface inspection device of the first aspect of the present invention, and the tablet in the inspection range is subjected to the inspection. The lighting step of illuminating by the illuminating means, and the light reflected from the side surface of the tablet by a plurality of reflectors arranged so as to surround the inspection range when viewed from the upper surface side of the tablet. The first inspection drum includes an imaging step of simultaneously imaging the reflected light from the upper surface of the tablet above the upper surface of the tablet and a processing step of processing the image signal obtained by the imaging. For the tablet, which is held in the tablet and whose length in the moving direction falls within the inspection range, the light and the reflected light from the surface are imaged once by the imaging means of the first visual inspection apparatus. For the tablet held on the first inspection drum and whose length in the moving direction exceeds the inspection range, a time difference according to the length of the tablet in the moving direction by the imaging means of the first visual inspection apparatus. For the tablet, which is switched to image the light and the reflected light from the surface a plurality of times, is held by the second inspection drum, and the length in the moving direction falls within the inspection range, the first. (2) The light and the reflected light from the back surface are imaged once by the imaging means of the visual inspection device, and the tablet is held by the second inspection drum and the length in the moving direction exceeds the inspection range. Switched to image the light and the reflected light from the back surface a plurality of times with a time difference according to the length of the tablet in the moving direction by the imaging means of the second visual inspection apparatus, and in the processing step, For the tablet whose length in the moving direction falls within the inspection range by the processing means of the first visual inspection apparatus, once on the surface side of the first visual inspection apparatus from the imaging means. The video signal is processed, and for the tablet whose length in the moving direction exceeds the inspection range, a plurality of video signals on the surface side from the imaging means of the first visual inspection device are combined. For the tablet whose length in the moving direction falls within the inspection range by the processing means of the second visual inspection apparatus, the one on the back surface side of the second visual inspection apparatus from the imaging means. For the tablet whose length in the moving direction exceeds the inspection range, a plurality of video signals on the back surface side from the imaging means of the second visual inspection apparatus are combined and processed. The outside is characterized by switching A visual inspection method is provided.

INDUSTRIAL APPLICABILITY The present invention makes it possible to provide a visual inspection method and a surface inspection apparatus capable of inspecting tablets that do not fit within the inspection range without causing an increase in cost and a decrease in inspection efficiency.

It is a figure which shows the embodiment of this invention, and is the figure which shows the whole structure of the surface inspection apparatus provided with the appearance inspection apparatus of the article to be inspected. It is a schematic block diagram which showed an example of the appearance inspection apparatus. It is a figure for demonstrating the arrangement relationship between the reflection means and the lighting means which constitute the appearance inspection apparatus of the article shown in FIG. It is an enlarged perspective view which showed only one of the reflectors constituting the appearance inspection apparatus of the article shown in FIG. It is a figure which shows typically the image which image | image | image | image | image | photographed the moving article to be inspected by the imaging means 30. It is a figure which shows the image of the upper surface S1 of the article S ′ to be inspected obtained by the bonding process. It is a figure which shows the image of the side surface S2 of the article S'to be inspected obtained by the bonding process. It is a figure which shows an example of the image which imaged the circular article S to be inspected.

Hereinafter, embodiments of the visual inspection method and the surface inspection apparatus of the present invention will be described with reference to FIGS. 1 to 8.
The following embodiments show one aspect of the present invention, do not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. Further, in the following drawings, in order to make each configuration easy to understand, the scale and number of each structure are different from the actual structure.

FIG. 1 is a diagram showing an overall configuration of the surface inspection device of the present invention including the visual inspection device of the article according to the present invention. The surface inspection device shown in FIG. 1 includes a front surface inspection drum 5 and a back surface inspection drum 6 which are horizontally supported by a wall portion 2 erected on the stage 1 and arranged vertically adjacent to each other, and tablets and candy on the surface inspection drum 5. , A supply device 7 for supplying an article to be inspected such as chocolate, a first visual inspection device (visual inspection device) 8 arranged on the side of the front surface inspection drum 5, and a side side of the back surface inspection drum 6. The second visual inspection device (visual inspection device) 9 arranged in the above, the discharge conveyor 10 for discharging the non-defective product after the inspection from the back surface inspection drum 6, and the defective product after the inspection from the back surface inspection drum 6 are collected. It is mainly composed of a receiving unit 11 for receiving the defective product and a receiving unit 12 for receiving the defective product to be inspected, which has been defective in discharging from the back surface inspection drum 6.

The surface inspection drum 5 (first inspection drum) transports the inspected article by rotating while sucking and supporting the inspected article on the outer peripheral surface with the upper surface of the inspected article facing outward. Is. As shown in FIG. 1, a back surface inspection drum 6 (second inspection drum) is rotatably installed under the surface inspection drum 5 with the outer peripheral surface close to the surface inspection drum 5. The back surface inspection drum 6 receives the article to be inspected from the surface inspection drum 5, and rotates while holding the article to be inspected by adsorbing and supporting it on the outer peripheral surface with the lower surface of the article to be inspected facing outward.

On the upper left side of the surface inspection drum 5 shown in FIG. 1, a transport device 7 for supplying the article to be inspected connected to the hopper 50 and housed inside the hopper 50 to the upper side of the surface inspection drum 5 is incorporated. The article to be inspected is supplied to the surface inspection drum 5 by the inclined chute 52 provided in the transport device 7.
Further, an inverted V-shaped transport passage 60 is installed on the lower center side of the back surface inspection drum 6 shown in FIG. A passage switching valve 61 is incorporated in the branch portion of the transport path 60, a receiving portion 12 for receiving defective discharged products is connected to the branch path 62 side on the left side of the transport path 60, and a branch path on the right side of the transport path 60. A conveyor device 10 for carrying out non-defective products is connected to the 63 side.

On the right side of the surface inspection drum 5 shown in FIG. 1, a first visual inspection device 8 is supported by a frame and installed. The first visual inspection device 8 is for inspecting the appearance of the article to be inspected, which is held and moves on the outer peripheral surface of the surface inspection drum 5. A second visual inspection device 9 is supported by a frame and installed on the left side of the back surface inspection drum 6. The second visual inspection device 9 is for inspecting the appearance of the article to be inspected, which is held and moves on the outer peripheral surface of the back surface inspection drum 6.

In the surface inspection device shown in FIG. 1, as the first visual inspection device 8 and the second visual inspection device 9, the visual inspection device for the article shown in FIG. 2 is provided. FIG. 2 is a schematic configuration diagram showing an example of an appearance inspection device for an article of the present invention. In FIG. 2, the description of the lighting device is omitted in order to make the drawing easier to see. Further, FIG. 3 is a diagram for explaining the arrangement relationship between the reflecting means and the lighting means constituting the appearance inspection device for the article shown in FIG. 2, and FIG. 3A shows the article to be inspected from the upper surface side. It is a figure which showed the arrangement relation of the reflection means, the lighting means, and an article to be inspected when it was seen, and FIG. It is a figure which showed the arrangement relation with. Further, FIG. 4 is an enlarged perspective view showing only one of the reflectors constituting the visual inspection apparatus for the article shown in FIG. 2. Here, an appearance inspection apparatus for performing an appearance inspection when the shape of the article S to be inspected is circular when viewed from the upper surface S1 side will be described.

The visual inspection device for an article shown in FIG. 2 includes a reflecting means 20, a lighting means (not shown in FIG. 2), an imaging means 30, and a processing means (not shown).
As shown in FIG. 2, the image capturing means 30 captures the emitted light 2d emitted from the reflecting means 20 and the reflected light 2e from the upper surface S1 of the article S to be inspected. As the image pickup means 30, one including an image pickup lens and an area sensor can be used.
Further, the processing means processes the video signal from the image pickup means 30, and is electrically connected to the image pickup means 30 by a connection means (not shown). As the processing means, for example, a PC (personal computer) or the like can be used. As for the function as the processing means, the function is realized by loading the program for realizing the function as the processing means into the memory provided in the PC and executing it by the CPU (central processing unit). Further, as the PC, a PC equipped with a monitor can be used. As the monitor, a display device including a CRT (Cathode Ray Tube), a liquid crystal display, or the like can be used.

As shown in FIG. 2, the reflecting means 20 reflects the reflected light 2a from the side surface S2 of the article S to be inspected. As shown in FIG. 3, the reflecting means 20 includes six reflectors 22, a U-shaped support member 23 that supports the upper portion of the reflector 22 so as to sandwich it, and a fixing plate 21 to which the support member 23 is attached. It is equipped with. The six reflectors 22 are fixed at predetermined positions by the support member 23 and the fixing plate 21. The fixing plate 21 has a ring shape, and blocks the emitted light 2d emitted from the reflector 22 toward the imaging means 30 and the reflected light 2e from the upper surface S1 of the article S to be inspected. There is no such thing.

Each reflector 22 is a prism made of glass or the like. Further, as shown in FIG. 2, all the reflectors 22 are arranged upward from the upper surface S1 of the article S to be inspected. As shown in FIG. 3A, the six reflectors 22 are arranged in an annular shape so as to surround the circular inspection range E as a center when viewed from the upper surface S1 side of the article S to be inspected. FIG. 3A shows a state in which the circular object S to be inspected is located within the inspection range E having a circular shape in a plan view. The inspection range E is arranged on the movement path of the article S to be inspected, which is moved by the rotation of the front surface inspection drum 5 or the back surface inspection drum 6. As an example, the moving direction of the article S to be inspected is a direction from the upper side to the lower side in the drawing as shown by an arrow in FIG. 3A.

The six reflectors 22 are arranged at equal intervals on a locus having a shape similar to the outer shape of the article S to be inspected, which is circular. Further, in the reflecting means 20 shown in FIG. 2, as shown in FIGS. 3A, 3B, and 4, the surface of the reflector 22 on the inspection range E (inspected article S) side is three planes. It is composed of 22a, and as shown in FIG. 3A, each plane 22a of each reflector 22 is arranged along each side of the hexagon. Therefore, in the reflecting means 20 shown in FIG. 2, as shown in FIG. 3A, the angle θ formed by the extending directions of the planes 22a and 22a of the two adjacent reflectors 22 and 22 is set to 120 °. There is.

Further, as shown in FIGS. 3A and 4, each reflector 22 has a plate shape having a constant thickness. As shown in FIG. 4, among the three planes 22a constituting the surface of the reflector 22 on the side to be inspected article S, the first plane 22c is provided at the position closest to the inspection range E (inspection article S). A third plane 22e is provided at a position farthest from the article S to be inspected, and a second plane 22d is provided between the first plane 22c and the third plane 22e. As shown in FIG. 4, the first plane 22c is tilted toward the inspection range E (inspected article S). Further, as shown in FIG. 4, the third plane 22e is parallel to the side surface S2 of the article S to be inspected, but may be tilted toward the article S to be inspected. Further, as shown in FIG. 4, the second plane 22d is tilted toward the article S to be inspected, but the extending direction of the second plane 22d is the side surface S2 of the article S to be inspected rather than the first plane 22c. It is said that it is close to the extending direction of.

Further, as shown in FIG. 4, the three planes 22a have an intrinsic reflection region 24 that reflects the reflected light 2a that is not reflected by another reflector 22 among the reflected light 2a from the side surface S2 of the article S to be inspected. , An overlap reflection region 25 that is arranged outside the intrinsic reflection region 24 and reflects the reflected light 2a that is also reflected by another adjacent reflector 22 is provided.

Further, as shown in FIG. 4, the outer surface 22f, which is the surface of the reflector 22 on the opposite side to the inspection range E (inspected article S), is composed of one plane, and is the same as the side surface S2 of the inspected article S. Although it is parallel, it may be tilted toward the article S to be inspected. Further, the top surface 22g of the reflector 22 is formed of one plane and may extend in a direction orthogonal to the side surface S2 of the article S to be inspected, but as shown in FIG. 2, the imaging means It may be tilted towards 30. When the angle of the top surface 22g is tilted toward the imaging means 30 from a direction orthogonal to the side surface S2 of the article S to be inspected, the emitted light 2d emitted from the reflecting means 20 is collected at a position closer to the center of the imaging means 30. Therefore, the resolution of the imaging means 30 can be effectively used, and the inspection accuracy can be further improved.

In the reflector 22 constituting the reflector 20 shown in FIG. 2, the reflected light 2a from the side surface S2 of the article S to be inspected is incident on the reflector 22 from the first plane 22c as shown in FIG. 4, and the outer surface 22f Is reflected by. The reflected light 2b reflected on the outer surface 22f is reflected on the second plane 22d. Then, as shown in FIGS. 2 and 4, the reflected light 2c reflected on the second plane 22d is emitted as the emitted light 2d toward the imaging means 30 via the top surface 22g.

In the reflecting means 20 shown in FIG. 3, the case where the shape of the inspection range E (inspected article S) is circular when viewed from the upper surface S1 side and the number of reflectors 22 is 6 is taken as an example. As described above, the number of reflectors 22 may be plural, and the number of reflectors 22 is not limited to six. The number of reflectors 22 is preferably in the range of 4-12, more preferably in the range of 6-8.

When the number of reflectors 22 is in the range of 4 to 12, as shown in FIGS. 3 (a), 3 (b), and 4, the surface of the reflector 22 on the inspection range E (inspected article S) side. When is composed of a plurality of flat surfaces 22a, the reflected light 2a reflected from the entire circumference of the side surface S2 of the article S to be inspected can be easily used as the reflective reflecting means 20, and the region is not inspected even if the visual inspection is performed. It can be a visual inspection device without a blind spot. Further, when the number of reflectors 22 is in the range of 6 to 8, the reflectors 22 are arranged at an angle close to parallel to the side surface S2 of the article S to be inspected when viewed from the upper surface S1 side of the article S to be inspected. The proportion of the flat surface 22a is increased, and the accuracy of the appearance inspection of the side surface S2 of the article S to be inspected can be improved.

Further, when the shape of the inspection range E (article S to be inspected) is circular when viewed from the upper surface S1 side, when the number of reflectors 22 exceeds 12, there is sufficient space for arranging the upper surface illumination means 41. Is not preferable because it becomes difficult to secure. Further, the video signal obtained from the light emitted from the reflecting means 20 has the side surface S2 of the article S to be inspected divided into a number corresponding to the number of reflectors 22. Therefore, when the number of reflectors 22 exceeds 12, the number of divisions of the video signal obtained from the light emitted from the reflecting means 20 becomes too large, and for example, the side surface S2 of the article S to be inspected is chipped. The divided video signal of the above may cause inconveniences such as difficulty in confirming the shape of the chip, and the accuracy of the appearance inspection of the side surface S2 of the article S to be inspected may be lowered.

The lighting means 40 constituting the reflecting means 20 shown in FIG. 2 irradiates the article S to be inspected, and is composed of a plurality of LEDs (light emitting diodes) and the like. As shown in FIGS. 3A and 3B, the lighting means 40 includes a top lighting means 41 and a side lighting means 42.

As shown in FIGS. 3A and 3B, the upper surface illuminating means 41 irradiates the upper surface S1 of the object to be inspected S1 from between adjacent reflectors 22, and the upper surface of the article S to be inspected S1. It is composed of six lighting devices 41b having two LEDs 41a and 41a arranged in the thickness direction of the article S to be inspected at an angle inclined with respect to S1 and the side surface S2. The top surface lighting means 41 may have the number of LEDs, the illumination intensity, and the illumination direction changed so that not only the top surface S1 of the article S to be inspected but also the side surface S2 can be illuminated.
Further, the side illumination means 42 irradiates the side surface of the inspection range E (inspected article S), and as shown in FIG. 3 (b), the inspection range E (inspected article S) is more than the reflection means 20. It is located close to. Further, as shown in FIG. 3A, the side lighting means 42 is a ring-shaped object arranged so as to surround the inspected article S as a center when viewed from the upper surface S1 side of the inspected article S. , A plurality of LEDs 42a are arranged in a ring shape.

Next, the operation and method of inspecting the appearance of the article to be inspected using the front surface inspection drum 5 and the back surface inspection drum 6 shown in FIG. 1 will be described with reference to FIGS. 5 to 7. Here, a case of inspecting the appearance of the oval-shaped inspected article S'as shown in FIG. 6 will be described as a deformed inspected article that is not circular in a plan view. The article to be inspected S'is conveyed with the longitudinal direction as the moving direction.

First, the front surface inspection drum 5 is rotated clockwise, and the back surface inspection drum 6 is rotated counterclockwise, so that the article S to be inspected is sequentially supplied to the surface inspection drum 5 from the chute 52. The supplied article S'to be inspected is attracted and supported on the outer peripheral surface of the surface inspection drum 5 with the upper surface S1 facing outward. Then, the article to be inspected S'held on the outer peripheral surface by the rotation of the surface inspection drum 5 is conveyed to a position facing the first visual inspection device 8, and the upper surface S1 and the article to be inspected are carried by the visual inspection device shown in FIG. The appearance of the side surface S2 is inspected.

In the visual inspection of the article S to be inspected here, the upper surface S1 and the side surface S2 of the article S'to be inspected are brightly illuminated by the upper surface lighting means 41 and the side lighting means 42 of the lighting means 40 shown in FIG. To. Then, as shown in FIG. 2, the reflected light 2a reflected on the side surface S2 of the article to be inspected S'is incident on the reflector 22 of the reflecting means 20, reflected twice in the reflector 22, and then imaged. It is emitted as emitted light 2d toward the means 30. Subsequently, the emitted light 2d emitted from the reflecting means 20 and the reflected light 2e from the upper surface S1 of the object to be inspected S'are imaged by the imaging means 30. After that, it is inspected whether or not the upper surface S1 and the side surface S2 of the article to be inspected S'have defects such as adhesion and dirt of foreign matter, deformation such as chipping and cracking, and printing defects.

5 (a) to 5 (c) are diagrams schematically showing images of a moving article to be inspected S'imaged by the imaging means 30, respectively. In FIGS. 5A to 5C, the article to be inspected S'moves from the right side to the left side in the figure. Further, in FIGS. 5A to 5C, for convenience, the two reflectors 22 arranged on the front side in the moving direction of the inspected article S'are designated as reflectors 22A and 22B, and the inspected article S'moves. The two reflectors 22 arranged on the rear side in the direction are shown as reflectors 22E and 22F, and the two reflectors 22 arranged between the reflectors 22A and 22B and the reflectors 22E and 22F are shown as reflectors 22C and 22D. Has been done.

As shown in FIGS. 5A to 5C, the width of the article to be inspected S'is a size that fits in the inspection range E, and the length of the article to be inspected S'is a size that exceeds the inspection range E. That's right. In this case, the imaging means 30 performs imaging of the inspection range E a plurality of times. The number of times of imaging is the nth time (n is) in order to cover the entire range of the article S'inspected by a plurality of imagings in the inspection range E and to align the captured images when they are combined. For the images taken at the (positive integer) and (n + 1) th times, the number of times that a part of the inspection article S'overlaps is set. In the present embodiment, one inspected article S'is imaged three times with a time lag.

As shown in FIG. 5A, the first imaging is performed at the timing when the front side of the object to be inspected S'in the moving direction falls within the inspection range E. As shown in FIG. 5 (b), in the second imaging, the intermediate portion of the inspected article S'in the moving direction falls within the inspection range E, and the first image and a part of the inspected article S' Is done at the timing of duplication. As shown in FIG. 5 (c), in the third imaging, the rear side of the inspected article S'in the moving direction falls within the inspection range E, and the second image and a part of the inspected article S'are included. It is done at overlapping timings.

FIG. 6 is a diagram showing an image of the upper surface S1 of the article to be inspected S'obtained by combining and processing the video signal from the imaging means 30 by the processing means. Of these images, the image V11 is an image obtained by the first imaging, and the image V12 is an image obtained by the second imaging, and a part of the image of the object to be inspected S'overlaps. There is. Further, the image V13 is an image obtained by the third imaging, and a part of the image of the article to be inspected S'overlaps. By combining (synthesizing) the images obtained by the three imagings in this way, images of all the upper surfaces S1 of the article to be inspected S'are obtained.

FIG. 7 is a diagram showing an image of the side surface S2 of the article to be inspected S'obtained by combining and processing the video signal from the imaging means 30 by the processing means. Of these images, the image V21 is an image obtained by the first imaging, and is an image of the side surface S2 of the object to be inspected S'reflected by the reflectors 22A and 22B, and a subject reflected by the reflectors 22C and 22D. Includes an image of the side surface S2 of the inspection article S'. The image V22 is an image obtained by the second imaging, and includes an image of the side surface S2 of the article to be inspected S'reflected by the reflectors 22C and 22D. The image V23 is an image obtained by the third imaging, and is an image of the side surface S2 of the inspected article S'reflected by the reflectors 22E and 22F, and an image of the inspected article S'reflected by the reflectors 22C and 22D. Includes an image of side surface S2.

Then, the processing means attaches, stains, or chips foreign matter to the upper surface S1 and the side surface S2 of the article to be inspected S'based on the combined image obtained by processing the three video signals output from the imaging means 30. Inspect for deformation such as cracks and cracks, or defects such as printing defects.

In order to facilitate understanding, an image of the upper surface S1 of the article to be inspected S'and an image of the side surface S2 of the article to be inspected S'are shown separately in FIGS. 6 and 7, but for example, the upper surface S1 The number of reflectors 22 around the image of the upper surface S1 and the number of times the imaging means 30 has taken an image, and corresponding to the position in the image of the upper surface S1 in a ring shape. It is also possible to arrange the image of the side surface S2 of'.

FIG. 8 is a diagram showing an example of an image of an article S to be inspected, which is circular in a plan view and fits within the inspection range E. As shown in FIG. 8, for the article S to be inspected, which is not limited to the circular shape but is within the inspection range E, an image of the entire range of the article S to be inspected can be obtained by one imaging by the imaging means 30. The processing means processes a single video signal output from the imaging means 30, so that foreign matter adheres to, stains, chips, cracks, or other deformations on the upper surface S1 and the side surface S2 of the article S to be inspected, or printing defects. Inspect for defects such as.

As described above, the number of times of imaging by the imaging means 30 and the presence or absence of the combination processing of the plurality of video signals by the processing means are switched according to the size of the objects to be inspected S and S'in the moving direction with respect to the size of the inspection range E. ..

As shown in FIG. 1, the article S'to be visually inspected by the first visual inspection apparatus 8 is lowered by the rotation of the front surface inspection drum 5, and at a position close to the back surface inspection drum 6, the back surface inspection drum 6 It is attracted and supported on the outer peripheral surface in a state of being turned inside out (a state in which the lower surface of the front surface inspection drum 5 is directed outward), and is rotated counterclockwise by the rotation of the back surface inspection drum 6. Then, when the article S'inspected in the inverted state is conveyed to a position facing the second visual inspection device 9 by the rotation of the back surface inspection drum 6, the figure which is separate from the first visual inspection device 8 and has the same configuration. The appearance inspection device of the article shown in 2 inspects the appearance of the upper surface S1 and the side surface S2 of the article to be inspected S'in the inverted state, as in the appearance inspection by the first appearance inspection device 8.

As shown in FIG. 1, the article S'to be visually inspected by the second visual inspection device 9 is lowered by the rotation of the back surface inspection drum 6, and is moved by the first visual inspection device 8 and the second visual inspection device 9. The inspected article S', which is regarded as a defective product in the visual inspection, is collected in the receiving portion 11, and the inspected article S', which is regarded as a non-defective product, is collected in the transport conveyor 10 side or the receiving portion 12 side via the transport passage 60. ..

As described above, the visual inspection apparatus of the present embodiment has a time difference according to the length of the inspected article S'in the moving direction with respect to the inspected article S'whose length in the moving direction exceeds the inspection range E. By imaging the inspected article S'multiple times and combining the obtained plurality of video signals, the inspected article S'is inspected without preparing another optical system for inspecting the inspected article S'. Appearance inspection can be carried out. Therefore, the visual inspection apparatus of the present embodiment can inspect the article to be inspected S'that does not fall within the inspection range without causing an increase in cost and a decrease in inspection efficiency, as in the case where another optical system is prepared.

Further, in the visual inspection apparatus of the present embodiment, when the moving inspected article S'is imaged a plurality of times, a part of the inspected article S'overlaps with respect to the images captured at the nth and (n + 1) th times. Since the image is taken at the timing, by combining the images with reference to a part of the overlapping article S'to be inspected, high-precision image combination becomes possible and the inspection accuracy can be improved.

Further, in the visual inspection apparatus of the present embodiment, the reflector 22 reflects the reflected light 2a that is not reflected by another reflector 22 of the reflected light 2a from the side surface S2 of the article S'inspected. Since it has 24 and an overlap reflection region 25 that is arranged outside the intrinsic reflection region 24 and reflects the reflected light 2a that is also reflected by another adjacent reflector 22, as shown below, The upper surface S1 and the side surface S2 of the article to be inspected S'can be inspected with even higher accuracy.

That is, the video signal obtained from the emitted light 2d emitted from the reflecting means 20 has the side surface S2 of the article to be inspected S'divided into a number corresponding to the number of reflectors 22. When the reflector 22 has an intrinsic reflection region 24 and an overlap reflection region 25, the object to be inspected S'is divided by the overlap reflection region 23 provided on each of the two adjacent reflectors 22. Since the reflected light 2a from the portion is reflected, the divided portion of the article to be inspected S'is inspected twice from angles in two directions. Therefore, the inspection accuracy of the divided portion of the article to be inspected S'is high, and the upper surface S1 and the side surface S2 of the article to be inspected S'can be inspected with even higher accuracy.

Further, since the surface inspection device of the present embodiment includes the visual inspection device of the present embodiment as the first visual inspection device 8 and the second visual inspection device 9, the length in the moving direction sets the inspection range E. It is possible to inspect the inspected article S'exceeding with high accuracy without causing an increase in cost and a decrease in inspection efficiency.

Although the preferred embodiments according to the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to the above examples. The various shapes and combinations of the constituent members shown in the above examples are examples, and can be variously changed based on design requirements and the like without departing from the gist of the present invention.

The appearance inspection device and the surface inspection device are not limited to the above-described embodiment, and for example, the number, shape, and arrangement of the reflectors are not limited to the above-described embodiment.
Further, the outer shape of the article to be inspected is not limited to a circular shape or an oval shape when viewed from the upper surface side of the article to be inspected, and the size in the direction orthogonal to the moving direction is within the inspection range E. If it fits, any shape such as an oval, an ellipse, or a polygon when viewed from the upper surface side of the article to be inspected can be handled.

5 ... Front surface inspection drum (first inspection drum), 6 ... Back surface inspection drum (second inspection drum), 8 ... First visual inspection device (visual inspection device), 9 ... Second visual inspection device (visual inspection device), 20 ... Reflecting means, 22 ... Reflector, 30 ... Imaging means, 40 ... Lighting means, E ... Inspection range, S, S'... Inspected article, S1 ... Top surface, S2 ... Side surface

Claims (5)

A first inspection drum for transporting the tablet by rotating while holding the back surface opposite to the front surface on the outer peripheral surface in the thickness direction with the surface in the thickness direction of the tablet facing outward.
The tablet is rotatably installed under the first inspection drum so that the outer peripheral surface is close to the lower side of the first inspection drum. The tablet is received from the first inspection drum, and the tablet is inverted with the conveyed state of the first inspection drum to reverse the back surface. A second inspection drum that rotates while holding the surface on the outer peripheral surface with the surface facing outward.
A first visual inspection device for inspecting the appearance of the tablet held on the outer peripheral surface of the first inspection drum, and a second visual inspection device for inspecting the appearance of the tablet held on the outer peripheral surface of the second inspection drum. Is equipped with
The first visual inspection device and the second visual inspection device target the tablet moving in the inspection range as an inspection target.
A lighting means for illuminating the tablet in the inspection range and
A reflective means that reflects the reflected light from the side surface of the tablet, and
One imaging means, which is arranged above the upper surface of the tablet and simultaneously images the light emitted from the reflecting means and the reflected light from the upper surface of the tablet.
Each of the processing means for processing the video signal from the imaging means is provided.
The reflecting means includes a plurality of reflectors arranged so as to surround the inspection range when viewed from the upper surface side of the tablet.
The imaging means of the first visual inspection apparatus once images the light and the reflected light from the surface of the tablet whose length in the moving direction falls within the inspection range, and in the moving direction. For the tablet whose length exceeds the inspection range, the light and the reflected light from the surface are switched to be imaged a plurality of times with a time difference according to the length of the tablet in the moving direction.
The processing means of the first visual inspection apparatus processes a single video signal on the surface side from the imaging means and moves the tablet whose length in the moving direction falls within the inspection range. For the tablet whose length in the direction exceeds the inspection range, a plurality of video signals on the surface side from the imaging means are switched to be combined.
The imaging means of the second visual inspection apparatus once images the light and the reflected light from the back surface of the tablet whose length in the moving direction falls within the inspection range, and in the moving direction. For the tablet whose length exceeds the inspection range, the light and the reflected light from the back surface are switched to be imaged a plurality of times with a time difference according to the length of the tablet in the moving direction.
The processing means of the second visual inspection device processes a single video signal on the back surface side from the imaging means and moves the tablet whose length in the moving direction falls within the inspection range. A surface inspection apparatus for switching a tablet whose length in a direction exceeds the inspection range so as to combine a plurality of video signals on the back surface side from the imaging means. In the imaging means, a part of the tablet overlaps with respect to the image captured at the nth (n is a positive integer) and the (n + 1) th time with respect to the tablet whose length in the moving direction exceeds the inspection range. The surface inspection apparatus according to claim 1, wherein the image is taken at the timing. The reflector has an intrinsic reflection region that reflects reflected light that is not reflected by another reflector of the reflected light, and a reflection that is arranged outside the intrinsic reflection region and is also reflected by another adjacent reflector. It has an overlap reflection region that reflects light, and from the light emitted from the reflection means, a video signal whose side surface of the tablet is divided into a number corresponding to the number of reflectors can be obtained. The surface inspection apparatus according to claim 1 or 2, wherein the overlap reflection region reflects the reflected light from the divided portion of the tablet in the divided video signal. The image of the tablet obtained from the imaging signal processed by the processing means corresponds to the image of the upper surface of the tablet, the number of reflectors around the image of the upper surface, and the number of times the imaging means has imaged. The surface inspection apparatus according to any one of claims 1 to 3, wherein the tablet has an image of the side surface of the tablet arranged in a ring shape. A visual inspection method for inspecting tablets whose inspection range is moved by using the surface inspection apparatus according to any one of claims 1 to 4.
A lighting step of illuminating the tablets in the inspection range by the lighting means,
The light reflected from the side surface of the tablet is reflected by a plurality of reflectors arranged so as to surround the inspection range when viewed from the upper surface side of the tablet, and the reflected light from the upper surface of the tablet. An imaging step of simultaneously imaging above the upper surface of the tablet, and
Including a processing step of processing the video signal obtained by imaging.
In the imaging step,
For the tablet held on the first inspection drum and whose length in the moving direction falls within the inspection range, the light and the reflected light from the surface are emitted by the imaging means of the first visual inspection apparatus. For the tablet which is imaged once and held by the first inspection drum and whose length in the moving direction exceeds the inspection range, the length of the tablet in the moving direction is obtained by the imaging means of the first visual inspection apparatus. Switching to image the light and the reflected light from the surface a plurality of times with a time difference corresponding to the difference.
For the tablet held on the second inspection drum and whose length in the moving direction falls within the inspection range, the light and the reflected light from the back surface are emitted by the imaging means of the second visual inspection apparatus. For the tablet which is imaged once and held by the second inspection drum and whose length in the moving direction exceeds the inspection range, the length of the tablet in the moving direction by the imaging means of the second visual inspection apparatus. Switching to image the light and the reflected light from the back surface a plurality of times with a time difference corresponding to the difference.
In the processing step,
For the tablet whose length in the moving direction falls within the inspection range by the processing means of the first visual inspection device, one time on the surface side of the first visual inspection device from the imaging means. For the tablet whose length in the moving direction exceeds the inspection range by processing the video signal, a plurality of video signals on the surface side from the imaging means of the first visual inspection device are combined. switching,
For the tablet whose length in the moving direction falls within the inspection range by the processing means of the second visual inspection device, one time on the back surface side of the second visual inspection device from the imaging means. For the tablet whose length in the moving direction exceeds the inspection range by processing the video signal, a plurality of video signals on the back surface side from the imaging means of the second visual inspection device are combined. A visual inspection method characterized by switching.

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