JP2015190872A - Device for inspecting bottoms of bottles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent, by setting a mask region only at a part indicating information, a defect from being overlooked.SOLUTION: The device comprises a first lighting device 3 for irradiating a bottle bottom 11 of a bottle 10, in which predetermined information is indicated on the bottle bottom so as to be raised or recessed from the surface of the bottle bottom, with a first illumination light L1 from a position opposite to the bottle bottom, and a second lighting device 4 for irradiating the bottle bottom 11 of the bottle 10 with a second illumination light L2 from a position deviated from the position opposite to the bottle bottom, the lighting devices being lit sequentially to photograph the bottle bottom under the lighting of each illumination light by a camera 5. After the part raised or recessed from the surface of the bottle bottom 11 is detected from a first image generated under the lighting of the first illumination light L1 to read information, mask data is created, the mask data specifying, as a mask region, the part from which the read information has been detected. The mask data is applied to an image generated under the lighting of the second illumination light L2 to set a mask region and an image of a defect is detected from an image region other than the mask region.

Description

  The present invention relates to a bottle bottom inspection apparatus for inspecting whether there is a defect in the bottle bottom by using images obtained by imaging the bottle bottom, for example, for various types of glass bottles. When the bottle is to be inspected with predetermined information displayed on the bottom of the bottle so that it rises or is recessed, the above information is read together with detection of defects such as bubbles at the bottom of the bottle. The present invention relates to a possible bottle bottom inspection device.

  Although there are various bottle defects, it is known to inspect foreign matter that has entered the bottom of the bottle using an image obtained by imaging the bottom of the bottle. By the way, in the bottle, information such as characters and symbols representing the manufacturer of the bottle and a model number representing the mold for producing the bottle is represented by, for example, a protrusion that rises from the surface of the bottle bottom to the bottle bottom. Generally, in the model number, the numerical value of each digit of an 8-bit code is represented by the presence or absence of a protrusion, and a plurality of protrusions are arranged along the circumference of a virtual circle. Furthermore, in order to enable visual confirmation, a number representing a model number may be represented by a protrusion.

  When inspecting this kind of bottle in the inspection process, the information (model number) represented by the protrusion is read from the image acquired by imaging the bottle bottom at a specific inspection station, and the model number read from each bottle and various types Inspection result information in which an inspection result is associated with each bottle is created, and the number of detected defects is tabulated for each defect type and model number using the inspection result information.

  In the image obtained by imaging the bottom of the bottle, there is a protrusion representing the information, and if there is a foreign object in the bottom of the bottle to be inspected, the foreign object is reflected. An inspection target area that does not include an image portion is set, and the presence or absence of foreign matter is inspected (see, for example, Patent Document 1).

  In the bottle bottom inspection device 9 shown in FIG. 16 described in Patent Document 1, an illumination device 92 is installed via a Fresnel lens 91 at a position below the bottle 10 to be inspected, and a camera 93 is positioned above the bottle 10. Are arranged. When the illumination light from the illumination device 92 is irradiated to the bottle bottom 11 through the Fresnel lens 91, the image of the bottle bottom 11 acquired by the camera 93 is an image in which the projection appears dark. Reading of the represented information is easy. In the figure, 94 is an image processing apparatus that executes processing for taking in an image acquired by the camera 93 and determining whether or not there is a foreign substance on the bottle bottom 11.

  In the above-described bottle bottom inspection device 9, the camera 93 is set to have a field of view so that the bottle bottom 11 is viewed from the bottle mouth 12 of the bottle 10, and the bottle bottom 11 is illuminated by the illumination device 92 at a lower position. An image is taken by the camera 93 through the mouth 12. The image acquired by the camera 93 is captured by the image processing device 94, and an image area of the bottle bottom 11 excluding the image area where the projection on the image exists is set as the inspection target area, and the image portion of the foreign matter is included in the inspection target area. Is checked to see if it exists.

Japanese Patent No. 4253742

  The bottle bottom inspection apparatus 9 described in Patent Document 1 detects a defect from other image areas as a mask area that excludes an image area including an image of a protrusion from an inspection target, but has no protrusion. The region is also included in the mask region. In particular, regarding the code of the model number, there is a region where the code does not exist (NULL) depending on the number represented, or the region where the code originally does not exist is included on the circumference where the protrusions are arranged. Instead, the entire donut-shaped area where the code is represented is set as the mask area. In this way, if the mask area is included up to the area where there is no protrusion, the defect will be overlooked if there is a defect in the area where there is no protrusion in the mask area.

  Further, in the bottle bottom inspection apparatus 9 described in Patent Document 1, since the protrusions on the bottle bottom 11 appear dark on the image, the reading accuracy is high, and foreign matter having a light shielding property also appears dark on the image. Although this type of foreign object detection accuracy is high, if the foreign object is hollow, such as a bubble, the bubble appears bright on the image because there is a significant amount of light that is refracted through the bubble. It is difficult to distinguish from the flat portion of the bottom of the bottle, and as a result, the detection accuracy of bubbles is low.

  The present invention has been made paying attention to the above problem, and generates an image in which defects such as bubbles that are difficult to distinguish from the flat portion of the bottle bottom clearly appear, and information is expressed for this image. Therefore, a defect inspection process is performed by masking only a portion where a raised portion or a recessed portion is reflected from the surface of the bottle bottom, thereby providing a bottle bottom inspection device with improved inspection accuracy. For the purpose.

  The bottle bottom inspection device according to the present invention is intended to inspect a bottle whose predetermined information is displayed on the bottom of the bottle so that it rises or is recessed from the surface of the bottle bottom. A first illumination device that emits illumination light from a position facing the bottom of the balance, and a second illumination that emits illumination light from a position deviating from the position facing the bottom of the bottle to be inspected. An apparatus, a camera for imaging a bottle bottom of a bottle to be inspected, a first image generated by the camera under illumination by the first illumination device, and generated by the camera under illumination by the second illumination device And an image processing apparatus for performing image processing for the inspection of the bottle bottom using the second image. An image processing device detects a portion raised from the surface of the bottle bottom or a recessed portion from the first image, and reads predetermined information displayed on the bottle bottom based on a pattern of the detected portion Mask data creating means for creating mask data using a portion detected by the reading means of the information read by the reading means as a mask area, and a mask area based on the mask data is set in the second image. And defect detecting means for detecting a defect image from the image area excluding the mask area.

  In the above-described bottle bottom inspection apparatus, the camera is disposed at a position facing the bottle bottom, or arranged with a field of view so as to look into the bottom of the bottle at the opposite position, that is, the position facing the bottle mouth. When the bottle to be inspected is positioned within the field of view of the camera arranged as described above, the bottle bottom is first imaged under illumination by the first illumination device to generate a first image, and then the second image is generated. The bottom of the bottle is imaged under illumination by the illumination device to generate a second image.

Illumination light from the first illumination device (hereinafter referred to as “first illumination light”) is emitted from the position facing the bottle bottom toward the bottle bottom, so that the first illumination light strikes the flat surface of the bottle bottom. Reflect or transmit. Regardless of whether the camera is placed on the bottle bottom side or the mouth side, a considerable amount of light travels toward the camera and the flat surface appears bright. For example, when information such as a model number is expressed by a protrusion so as to rise from the surface of the bottle bottom, the first illumination light or the inclined surface reflected by the inclined surface of the protrusion when the first illumination light hits the protrusion Since a considerable amount of the first illumination light entering the bottom of the bottle travels in a direction different from the direction of the camera, the inclined surface appears dark. The first illumination light reflected from the top of the projection or the first illumination light entering the bottle bottom from the top has a considerable amount of light traveling toward the camera, so the top appears bright. As a result, the projection becomes an image that is bordered by a dark portion of the inclined surface, and information represented by the projection can be easily read based on a pattern having the border as an outline.
Even when the information such as the model number is represented by a V-shaped groove so as to be recessed from the surface of the bottle bottom, the illumination light hitting the groove proceeds in the same manner as described above.

  When a bubble is present at the bottom of the bottle, the boundary between the hollow portion of the bubble and the bottle forms a substantially flat surface that is substantially parallel to the bottom of the bottle. Therefore, when the first illumination light strikes the bubble, A significant amount of the first illumination light reflected at the boundary or the first illumination light entering the bottle from the boundary through the hollow portion of the bubble travels toward the camera, and the bubble portion appears bright. As a result, the bubble and the flat surface at the bottom of the bottle are almost indistinguishable on the image.

Illumination light from the second illumination device (hereinafter referred to as “second illumination light”) is directed to the inspection position from a position deviating from the position facing the bottle bottom, and is obliquely applied to the bottle bottom of the bottle. Therefore, a considerable amount of the second illumination light reflected obliquely on the flat surface of the bottle bottom or transmitted through the bottom of the bottle proceeds in a direction other than the direction of the camera, and the flat surface appears dark. .
When the second illumination light hits the projection representing the information such as the model number, a considerable amount of light of the second illumination light reflected from the inclined surface of the projection or the second illumination light entering the bottle bottom from the inclined surface is received. As it moves toward the camera, the inclined surface appears bright. Part of the second illumination light reflected by the top of the inclined surface or reflected from the top and entering the bottom of the bottle travels toward the camera, so that the top appears bright. As a result, the projection becomes an image in which the brightly reflected portions of the inclined surface and the top portion are white, and the information represented by the projection can be read.
Even when the information such as the model number is represented by a V-shaped groove so as to be recessed from the surface of the bottle bottom, the illumination light hitting the groove proceeds in the same manner as described above.

  When a bubble is present at the bottom of the bottle, the boundary between the hollow portion of the bubble and the bottle forms a substantially flat surface that is substantially parallel to the bottom of the bottle. Therefore, when the second illumination light strikes the bubble diagonally, A significant amount of the second illumination light reflected at the boundary between the bottle and the second illumination light that has entered the bottle from the boundary through the bubble hollow portion travels in a direction other than the direction of the camera. However, in the peripheral part of the bubble that is not parallel to the bottom of the bottle, a considerable amount of the second illumination light reflected at the boundary between the bubble hollow part and the bottle or the second illumination light entering the bottle from the boundary through the bubble hollow part. As the amount of light travels towards the camera, the surrounding area of the bubble appears bright. As a result, in the second image generated by the camera under the second illumination, the outline of the bubble becomes clear and it is possible to distinguish the bubble from the flat surface of the bottle bottom.

  As described above, in the first image generated under illumination by the first illuminating device, the projections or grooves that represent the information are clearly reflected. Therefore, in the image processing device, the projections or the grooves are extracted from the first image. A portion can be detected, and the information displayed on the bottom of the bottle can be accurately read based on the pattern of the detected portion. Here, the “pattern of the detected portion” refers to the shape of the protrusions or grooves that follow each letter or number, or the arrangement of a plurality of protrusions or recesses that represent the code.

  In the first image, defects such as bubbles do not appear clearly, but in the second image generated under the second illumination, bubbles appear clearly with protrusions or grooves that represent information and are generated from the first image. Since the projection or the groove portion is excluded from the inspection target by setting the mask area based on the mask data, the projection or the groove representing the information is not erroneously detected as a defect. In addition, since only the portion where the image corresponding to the projection or the groove appears for each individual projection or the groove is set as the mask area, the defect existing in the portion where the protrusion or the groove does not exist is set. Oversight can be prevented.

  In a preferred embodiment of the present invention, the mask data creating means expands the contour of the portion detected by the reading means in the width direction, and uses the mask data with the image area represented by the expanded contour as the mask area. To create. Since the illumination conditions are different between the imaging under the first illumination and the imaging under the second illumination, even if the same bottle is imaged, the projections or the grooves in the first image There may be a slight shift between the protrusions or the grooves in the second image. According to the mask data of this embodiment, the second image is provided with a mask area that is slightly wider than the protrusions or grooves in the first image. Even when the object or the groove portion is deviated from the portion detected from the first image, the misplaced portion can be prevented from being erroneously detected as a defect without being masked.

  According to the present invention, after the information is correctly read using the first image in which the protrusions or concave grooves representing the bottle information clearly appear, defects such as bubbles that do not clearly appear in the first image clearly appear. For the second image, the defect detection process is performed by setting the mask area only in the projection or the groove portion based on the mask data created from the first image, so that the defect that has occurred in the portion where the projection does not exist Oversight can be prevented, and the accuracy of inspection is greatly improved.

It is a top view which shows schematic structure of the bottle inspection apparatus in which the bottle bottom inspection apparatus of this invention was installed. It is a bottom view of the bottle which shows an example of a bottle bottom. It is a figure which shows schematic structure of the bottle bottom inspection apparatus which is one Example of this invention. It is a figure which shows schematic structure of a 1st illuminating device. It is explanatory drawing which shows each state of the permeation | transmission and reflection of light when the 1st illumination light by a 1st illuminating device is irradiated to the protrusion of a bottle bottom. It is explanatory drawing which shows each state of permeation | transmission and reflection of light when the 1st illumination light by a 1st illuminating device is irradiated to the bubble of a bottle bottom. It is explanatory drawing which shows each state of the permeation | transmission and reflection of light when the 2nd illumination light by a 2nd illuminating device is irradiated to the protrusion of a bottle bottom. It is explanatory drawing which shows each state of permeation | transmission and reflection of light when the 2nd illumination light by a 2nd illuminating device is irradiated to the bubble of a bottle bottom. It is a figure which shows the image of the bottle bottom acquired under the lighting state of the 1st illuminating device. It is a figure which shows the image of the bottle bottom acquired under the lighting state of the 2nd illuminating device. It is a functional block diagram which shows the function with which the control part of an image processing apparatus is provided. It is explanatory drawing which shows the outline | summary of the creation process of a mask data, and the detection process of a bubble. It is a flowchart which shows the procedure of the reading process of information, and the detection process of a bubble. It is a figure which shows the example which set the process area for reading of information with respect to the binary image of a 1st image. It is explanatory drawing which shows the procedure of the process which produces mask data using the black pixel area | region detected from the binary image of the 1st image. It is a figure which shows schematic structure of the conventional bottle bottom inspection apparatus.

  FIG. 1 shows a schematic configuration of a bottle inspection apparatus in which the bottle bottom inspection apparatus of the present invention is installed. The bottle inspection apparatus in the figure has a configuration in which a plurality of inspection stations are arranged in a circle around the star wheel 20. In FIG. 1, only the final inspection station T is shown, and the other inspection stations are not shown. The star wheel 20 includes a plurality of recesses 21 into which glass bottles 10 to be inspected (hereinafter simply referred to as “bottles”) 10 are introduced on the outer peripheral surface. The star wheel 20 is intermittently fed at a predetermined angle in a direction indicated by an arrow P in the drawing by an intermittent rotation mechanism (not shown), whereby each bottle 10 is sequentially guided to each inspection station. In the figure, 22 is a bottle supply mechanism for supplying the bottle 10 sent from the bottle making machine by the conveyor to the star wheel 20, and 23 is a non-defective product according to the inspection result. It is a discriminating mechanism that discriminates between products and defective products. Non-defective products are sent out to the carry-out conveyor by the discriminating mechanism 23, and defective products are collected on a reject table.

  The bottle making machine is divided into a plurality of sections, and two rough molds and finish molds are provided for each section. The parison molded in the rough mold is finished into a final form bottle in the finishing mold. At the bottom of the final bottle, as shown in FIG. 2, a number 13 such as “136” indicating the model number of the mold in which the bottle 10 is molded, a dot sequence 14 indicating the model number as a code, a bottle The information such as the character 15 such as “YS” representing the manufacturer is arranged on the same circumference or concentric circles. These numbers 13, the point sequence 14, and the characters 15 are represented by protrusions that rise from the surface of the bottle bottom 11, that is, protrusions whose cross section is chevron shaped.

  The bottle 10 in the illustrated example is a defective product in which bubbles X are present near the surface of the outer peripheral portion of the bottle bottom 11 and the portion where the code by the point sequence 14 is represented, and the bottle bottom inspection apparatus 1 shown in FIG. The model number represented by the protrusion on the bottom 11 is read, and it is inspected whether foreign matter such as bubbles X is present on the bottle bottom 11.

  The bottle bottom inspection apparatus 1 in the illustrated example is installed in the final inspection station T of the bottle inspection apparatus in FIG. 1, and information such as a model number is represented by protrusions on the bottle bottom 11, and the bottle 10 is an inspection target. Reading and bottle bottom defect inspection. In the following description, attention is paid to foam as a defect of the bottle bottom 11 to be inspected. However, the bottle bottom inspection apparatus 1 can inspect foreign matters other than foam (for example, abnormal melting portions of glass, etc.). is there.

  The bottle bottom inspection device 1 includes a positioning mechanism 2 that positions the bottle 10 to be inspected at the inspection position without blocking the bottle bottom 11. The positioning mechanism 2 includes, in addition to the star wheel 20 and its intermittent rotation mechanism, a table 24 provided horizontally at the final inspection station T position. The illustrated table 24 has an opening 25 of a size and shape that allows the entire bottom of the bottle bottom 11 to be exposed from the lower surface at the center of the table 24 in order to position the bottle bottom 11 without being blocked. Is formed. The shape and size of the opening 25 are matched with the bottle bottom 11 of the bottle 10 to be inspected, and when the inspection object is replaced with one having a different shape or size, the bottle bottom of the bottle 10 is inspected. 11 is replaced with a table 24 having an opening 25 in accordance with the shape and size of 11.

  The bottle bottom inspection device 1 is positioned at the inspection position, and a first illumination device for irradiating the bottle bottom 11 of the bottle 10 with the first illumination light L1 at a substantially right angle from a position facing the bottle bottom 11 below the bottle bottom 11. 3, a second illumination device 4 for irradiating the second illumination light L2 obliquely from a position deviating from the facing position of the bottle bottom 11 of the bottle 10 below the bottle bottom 11, Lighting of the camera 5 such as a CCD camera and the first and second illuminating devices 3 and 4 disposed at a position facing the bottle bottom 11 below the bottle bottom 11 so that the entire bottle bottom 11 is included in the visual field w. , A controller 6 that controls each operation of turning off, and an image processing device 7 that captures an image acquired by the camera 5 and executes predetermined image processing. The bottle inspection apparatus 1 shown in FIG. 1 is a timing controller (not shown) that gives the controller 6 start timing of inspection or receives the inspection result of the bottle bottom 11 and gives drive timing to the discrimination mechanism 23. ).

  In the bottle bottom inspection, the controller 6 first sets a state in which only the first lighting device 3 is turned on, and then executes control to switch from that state to a state in which only the second lighting device 4 is turned on. The image processing device 7 first executes a process of reading information such as the model number of the bottle bottom 11 from the image of the bottle bottom 11 acquired by the camera 5 under a state in which only the first illumination device 3 is turned on. Processing for determining presence / absence of bubble X in bottle bottom 11 from the image area excluding the image area where the projection is present in the image of bottle bottom 11 acquired by camera 5 with only second lighting device 4 turned on Execute.

In FIG. 3, c indicates the central axis (axial core) of the bottle 10 that is localized at the inspection position. The illumination device 3 and the camera 5 are arranged in this order.
The second illumination device 4 is configured such that the first illumination light L1 from the first illumination device 3 over the entire bottle bottom 11 is not blocked so that the field of view w of the camera 5 including the entire bottle bottom 11 is not blocked. The ring-shaped light source is penetrated by the central portion. This ring-shaped light source has a structure in which a plurality of LEDs are mounted in the same direction on a substrate with a hollowed central portion, and the upper part of the LEDs is covered with a diffusion plate, and penetrates through the central portion. A circular through hole 41 is formed. This second illumination device irradiates the second illumination light L2 obliquely from a position deviating from the facing position with the bottle bottom 11 below the bottle bottom of the bottle 10, and the entire bottle bottom 1. So that the first illumination light L1 from the first illumination device 3 over the entire bottom of the bottle 11 is not obstructed, and the diameter of the through hole 41 is the opening of the table 24. It is desirable to use a donut shape larger than the portion 25.

In the first lighting device 3, the portion that projects the first illumination light L <b> 1 toward the bottle bottom 11 is configured by the transparent light guide plate 30 so that the field of view w of the camera 5 including the entire bottle bottom 11 is not obstructed. Is.
FIG. 4 shows a schematic configuration of the first illumination device 3, and a plurality of LEDs 31 are arranged on the outer peripheral end face of the transparent light guide plate 30 toward the center direction. In the central portion of one surface of the light guide plate 30, a reflection portion 32 is formed that reflects part of the light of the LED 31 introduced into the light guide plate 30 and guides it toward the other surface. The reflecting portion 32 corresponds to a portion for projecting the first illumination light L1 toward the bottle bottom 11, and the first illumination light L1 reflected toward the camera 5 at the bottle bottom 11 is taken into the camera 5 through the reflection portion 32. It is.

  FIG. 5 shows a state in which the first illumination light L1 from the first illumination device 3 is applied to the protrusion 16 rising from the surface of the bottle bottom 11, and FIG. 6 shows the first illumination light L1 on the bottle bottom 11. The state irradiated to the bubble X which exists in the surface vicinity is each shown. The protrusion 16 represents information such as a numeral 13 indicating the model number of the mold in which the bottle is molded, a dot sequence 14 indicating the model number as a code, and a character 15 indicating the manufacturer of the bottle.

  When the first illumination light L1 from the first illumination device 3 hits the flat surface 11a of the bottle bottom 11, the first illumination light L1 is reflected and a considerable amount of light travels toward the camera 5, so the flat surface 11a. Appears bright. In the drawing, a bright portion is indicated by “bright” characters, and a dark portion is indicated by “dark” characters. The first illumination light L1 from the first illumination device 3 is indicated by a thick dotted line, and the reflected light and transmitted light at the bottle bottom 11 are indicated by thin dotted lines.

  When the first illumination light L1 from the first illumination device 3 hits the protrusion 16, the first illumination light L1 that hits the inclined surface 16b of the protrusion 16 is not reflected toward the camera 5, and the inclined surface 16b appears dark. . The first illumination light L1 hitting the top 16a of the projection 16 is reflected and a considerable amount of light travels toward the camera 5, so that the top 16a appears bright. As a result, the protrusion 16 becomes an image bordered by a dark portion of the inclined surface 16b, specifically an image as shown in FIG. 9 (hereinafter referred to as “first image”) G1, and the protrusion. The information represented by 16 is easy to read.

  When the bubble X exists in the bottle bottom 11, the boundary between the hollow portion of the bubble X and the bottle 10 forms a substantially flat surface parallel to the bottle bottom 11, so that the first illumination by the first lighting device 3 is performed. When the light L1 hits the bubble X, the first illumination light L1 is reflected at the boundary between the hollow portion of the bubble X and the bottle 10, and a considerable amount of light travels toward the camera 5, and the portion of the bubble X (in FIG. 9) (Shown with a dotted line) appears bright. As a result, the bubble X and the flat surface 11a of the bottle bottom 11 are almost indistinguishable on the image.

FIG. 7 and FIG. 8 show the state in which the second illumination light L2 from the second illumination device 4 is irradiated to the protrusion 16 rising from the surface of the bottle bottom 11 and the bubble X existing in the vicinity of the surface of the bottle bottom 11, respectively. Show.
When the second illumination light L2 from the second illumination device 4 strikes the flat surface 11a of the bottle bottom 11 obliquely, a considerable amount of the second illumination light L2 is reflected in a direction other than the direction of the camera 5, The flat surface 11a appears dark. When the second illumination light L2 from the second illumination device 4 hits the protrusion 16, the second illumination light L2 hitting the inclined surface 16b of the protrusion 16 reflects a considerable amount of light toward the camera 5. The inclined surface 16b appears bright. Part of the second illumination light L2 that has hit the top 16a of the protrusion 16 is reflected toward the camera 5, so that the top 16a appears bright. As a result, the protrusion 16 has an image in which the brightly reflected portions of the inclined surface 16b and the top portion 16a are white, specifically, an image as shown in FIG. 10 (hereinafter referred to as “second image”) G2. Thus, the information represented by the protrusion 16 can be read.

  When the bubble X exists in the bottle bottom 11, the boundary between the hollow portion of the bubble X and the bottle forms a substantially flat surface that is substantially parallel to the bottle bottom 11, so that the second illumination light from the second illumination device 4 When L2 strikes the bubble X at an angle, a considerable amount of light of the second illumination light L2 is reflected in a direction other than the direction of the camera 5 at the boundary between the hollow portion of the bubble X and the bottle 10, but parallel to the bottle bottom 11. In the peripheral portion of the bubble X that is not, a considerable amount of light of the second illumination light L2 is reflected toward the camera 5 at the boundary between the hollow portion of the bubble X and the bottle 10, so that the peripheral portion of the bubble X appears bright. As a result, in the second image G2 shown in FIG. 10, a linear image LX with a bright peripheral portion of the bubble X appears, and the bubble X and the flat surface 11a of the bottle bottom 11 can be distinguished on the image. It becomes.

  In this embodiment, the second illuminating device 4 and the first illuminating device 3 are disposed below the bottom 11 of the bottle 10 to be inspected in the order of the second illuminating device 4 and the first illuminating device 3, and further the first illuminating device By disposing the camera 5 below the device 3, the reflected light from the bottle bottom 11 with respect to the first illumination light L1 and the second illumination light L2 enters the camera 5. However, the present invention is not limited to this. Is placed in a position opposite to the bottle mouth of the bottle 10 so that the field of view is determined so that the bottle bottom 11 is seen from the bottle mouth, and is transmitted through the bottle bottom 11 from each lighting device 3, 4 and enters the camera 5. You may produce | generate the image by 1st, 2nd illumination light L1, L2 to do. Also in this case, an image similar to the first image G1 in FIG. 9 can be obtained under illumination by the first illumination device 3, and a second image in FIG. 10 is obtained under illumination by the second illumination device 4. Images similar to G2 can be acquired.

  In addition, the information expressed in the bottle bottom 11 is not limited to the bottle 16 that is raised from the surface of the bottle bottom 11 as in the above-described embodiment, but is inclined and recessed from the surface of the bottle bottom 11. Even when inspecting a bottle represented by a groove or recess, that is, a groove or recess having a V-shaped cross section, under the illumination by the first illumination device 3, it is the same as the first image G1 in FIG. An image can be acquired, and an image similar to the second image G2 in FIG. 10 can be acquired under illumination by the second illumination device 4.

FIG. 11 is a functional block diagram illustrating the configuration of the control unit of the image processing apparatus 7 that captures and processes the first image G1 and the second image G2 illustrated in FIGS. 9 and 10 from the camera 5 according to the functions of the control unit. It is.
The image processing apparatus 7 of this embodiment has a control unit composed of a computer. The control unit includes an image input unit 71, a preprocessing unit 72, a character recognition processing unit 73, and a number recognition processing unit 74 by a dedicated program. Each function such as a code recognition processing unit 75, a mask data creation unit 76, a mask processing unit 77, a defect detection unit 78, a determination unit 79, and a determination result output unit 70 is set. Further, in the memory of the control unit, a first storage unit 701 in which a reference image of characters 15 indicating the manufacturer of the bottle 10 is registered, a second storage unit 702 in which reference images of numbers 0 to 9 are registered, a model number A third storage unit 703 in which a template used for processing for reading a code is registered is provided.

  The image input unit 71 captures the first and second images G <b> 1 and G <b> 2 from the camera 5 in accordance with the lighting timing of the first lighting device 3 and the second lighting device 4 in accordance with a command from the controller 6. . The pre-processing unit 72 performs binarization processing by the dynamic threshold method on each of the first and second images G1 and G2, and then performs expansion processing and contraction processing for a plurality of cycles. The captured images G1 and G2 are converted into binary images from which noise is removed and whose contour portions are smoothed.

When the first image G1 generated under illumination by the first lighting device 3 is captured, the first image G1 is binarized by the processing in the preprocessing unit 72, and then the character recognition processing unit 73, the number The recognition processing unit 74 and the code recognition processing unit 75 are operated, and the registration data of the first to third storage units 701 to 703 is used for the binary image to represent the character 15 representing the manufacturer and the number representing the model number. 13. The code indicated by the point sequence 14 is read. When the reading is completed normally, the mask data creating unit 76 creates mask data using the image of the protrusion 16 detected for the read information from the binary image and processed for the reading.
As will be described later, when it is detected in the recognition processing of the character recognition processing unit 73 that the width direction of the character 15 of the first image G1 is inclined with respect to the horizontal direction of the image, preprocessing is performed. Rotation correction of the binary image is performed by the unit 72 so that the width direction of the image of the character 15 is in a state along the horizontal direction of the image, and the numbers by the number recognition processing unit 74 are applied to the corrected binary image. Recognition processing and code recognition processing by the code recognition processing unit 75 are performed.

  When the second image G2 generated under illumination by the second illuminating device 4 is captured, after the processing in the preprocessing unit 72, the mask processing unit 77 is first operated to be converted from the second image G2. Then, a mask region based on the mask data created by the mask data creation unit 76 is set in the binary image, and then a defect detection process is performed by the defect detection unit 78, and further, the determination unit 79 determines whether there is a defect. Is done. The determination result output unit 70 outputs the inspection results for each individual bottle 10 as a pair with the information recognized by the recognition processing units 73, 74, and 75. Note that when the rotation correction is performed on the binary image of the first image G1, the same correction is performed on the binary image of the second image G2.

  FIG. 12 shows an example of the first image G1 shown in FIG. 9 and the second image G2 shown in FIG. 10, and creates mask data based on the read result of the first image G1, and uses the mask data to generate the second data. The outline | summary of the process which detects a bubble from the image G2 is shown.

  FIG. 12A shows a first image G1 similar to that shown in FIG. 9, and FIG. 12B shows a binary image G1 ′ generated by the processing of the preprocessing unit 72 for the first image G1. . The first image G1 generated by the action of the first illumination light L1 described with reference to FIGS. 5 and 6 is a black image corresponding to a dark portion of the inclined surface 16b of each protrusion 16 by the processing of the preprocessing unit 72. The pixels are converted into a binary image G1 ′ that is smoothly continuous with a certain width without interruption. That is, in the binary image G1 ′, each protrusion 16 is represented by a linear black pixel region along the outline thereof. On the other hand, the faint reflection portion of the bubble X in the first image G1 is converted into a white pixel region in the binary image G1 ′. After the recognition processing by the character recognition processing unit 73, the number recognition processing unit 74, and the code recognition processing unit 75 is performed on the binary image G1 ′, the mask data creation unit 76 performs the processing as shown in FIG. Mask data is created.

  FIG. 12D shows a second image G2 similar to that shown in FIG. 10, and FIG. 12E shows a binary image G2 ′ generated from the second image G2. In the second image G2 generated by the action of the second illumination light L2 described with reference to FIGS. 7 and 8, the flat surface of the bottle bottom 11 becomes a black pixel region by the processing of the preprocessing unit 72, and the peripheral portion of the bubble X Is converted into a binary image G2 ′ in which a portion in which the inclined surface 16b and the top portion 16a of each protrusion 16 appear bright is a white pixel region. The mask processing unit 77 sets a mask area for the binary image G2 ′ using the mask data shown in FIG. 12C, and as shown in FIG. The portion in which each protrusion 16 is reflected is excluded from the processing target.

  FIG. 13 shows a processing procedure from reading of a model number to detection processing of the bubble X performed by the image processing device 7 and the controller 6. These procedures (each procedure is indicated by “ST” in the figure) are sequentially and repeatedly executed in accordance with the timing at which the bottle 10 is introduced into the inspection position. Hereinafter, each procedure in FIG. 13 will be described with reference to FIGS. 14 and 15 in addition to FIG.

  When the bottle 10 to be inspected is introduced into the inspection position of the final inspection station T shown in FIG. 1, the determination of ST1 in FIG. 13 becomes “YES”, and the controller 6 turns on the first lighting device 3, The first illumination light L1 from the first illumination device 3 is irradiated to the bottle bottom 11 of the bottle 10 (ST2). In the next ST3, the bottle bottom 11 is imaged by the camera 5 under the lighting state of the first lighting device 3, and the first image G1 (see FIG. 12A) acquired by the camera 5 is the image processing device. 7 and is stored in an image memory (not shown).

  When the capture of the first image G1 is finished, the binarization process (ST4), the expansion process and the contraction process (ST5) by the pre-processing unit 72 are sequentially performed, and the first image G1 is as shown in FIG. It is converted into a binary image G1 ′.

  The character recognition processing unit 73 performs a pattern matching process on the binary image G1 ′ using the character reference image in the first storage unit 701, so that the region R1 including the image of the character 15 representing the manufacturer (FIG. 14). Reference) is detected (ST6). By this process, an angle representing the inclination of the region R1 with respect to the character reference image (corresponding to the inclination in the width direction of the character 15 with respect to the horizontal direction of the image described above) is detected. The pre-processing unit 72 performs image rotation correction for eliminating the inclination. The angle used for this correction is temporarily stored for processing on the second image G2, which will be described later.

After the rotation correction, recognition processing (ST8) by the numerical value recognition processing unit 74 is performed, and then recognition processing (ST9) by the code recognition processing unit 75 is performed.
First, in ST8, the numerical value recognition processing unit 74 sets a donut-shaped reference search area S including the reference area R1, as shown in FIG. 14, and the reference search area S is within the reference search area S. The reading region R2 is set at a position facing the region R1 across the circular region inside the. Further, the number recognition processing unit 74 recognizes individual numbers included in the reading region R2 using the reference images of various numbers registered in the second storage unit 702.

  In ST9, the code recognition processing unit 75 collates the circular image region inside the reference search region S using the template registered in the third storage unit 703. The dot sequence 14 of this embodiment has a configuration in which a mark code is combined with an 8-bit code representing a model number, and the third storage unit 703 corresponds to each digit of the entire code including the mark code. A template representing the presence / absence of the protrusion 16 in the area corresponding to the pattern of area arrangement (indicating the size and positional relationship of each area) and the mark of the mark in the pattern is registered. The code recognition processing unit 75 changes the position and rotation angle of the template in various ways and collates the region inside the reference search region S of the binary image G1 ′ with the template, so that the mark is recognized in the reference search region S. An area representing a code is detected. Further, the binary image G1 ′ is collated with the template in a state where the detected area is aligned with the area corresponding to the mark of the mark, and a protrusion is formed in the area corresponding to each digit of the 8-bit code representing the model number. It is determined whether there is a black pixel region representing 16 contours, and a code representing the model number is recognized from the determination result.

  If the model number is properly read in ST8 and ST9, the determination in ST10 is “YES”, and the process proceeds to ST11. The mask data creation unit 76 reads the information read in each recognition process in ST6, ST8, and ST9. Mask data is created using the linear black pixel region used in the above.

  FIG. 15 shows the mask data using the black pixel region representing the outline of the protrusion 16 representing the character “S” in the linear black pixel region appearing in the binary image G1 ′ of FIG. An example to create is shown. The process of ST11 will be described with reference to FIG. 15. The mask data creation unit 76 in the binary image G1 ′ recognizes the black pixel region recognized as representing the character “S”, in other words, the read character information “ A linear black pixel region (see FIG. 15A) representing the outline of the protrusion 16 representing “S” is expanded by a predetermined number of pixels in the width direction. Specifically, as shown in FIG. 15B, the boundary positions for the adjacent white pixel regions are moved to the side of the white pixel region by a predetermined number of pixels, respectively (in FIG. 15B, for easy understanding). The expanded black pixel region is shown by a halftone dot pattern). Further, the mask data creation unit 76 sets mask data (FIG. 15C) for masking the entire image region surrounded by the expanded black pixel region. As specific mask data, for example, the value “1” is set for all pixels in the expanded black pixel region and the white pixel region surrounded by the black pixel region, and the value “0” is set for the other pixels. The binary data is obtained.

  Returning to FIG. When the mask data is created, the controller 6 then turns off the first lighting device 3 and turns on the second lighting device 4, and the second illumination light L <b> 2 is irradiated to the bottle bottom 11 of the bottle 10. (ST12). In the next ST13, the bottle bottom 11 is imaged by the camera 5 under illumination by the second illumination light L2, and the second image G2 (see FIG. 12D) acquired by the camera 5 is imaged by the image input unit 71. The data is taken into the processing device 7 and stored in an image memory (not shown).

  The pre-processing unit 72 performs binarization processing on the second image G2 in ST14, and performs expansion processing and contraction processing in ST15, and the second image G2 is shown in FIG. Such a binary image G2 ′ is converted (ST14, ST15). In next ST16, the pre-processing unit 72 performs rotation correction of the binary image G2 ′ of the second image G2 using the angle used in the correction processing of ST7.

  Next, the mask processing unit 77 sets a mask area based on the mask data created in ST11 to the binary image G2 ′ of the second image G2 (ST17). By setting the mask area, the binary image G2 ′ is in a state where the white pixel area representing the protrusion 16 is masked, as shown in FIG.

  The defect detection unit 78 performs a bubble X detection process by measuring white pixels included in the image region excluding the mask region (ST18), and the determination unit 79 uses the measurement value to determine the presence or absence of the bubble. Determine (ST19). Specifically, the determination unit 79 collates the measurement value of the white pixel with a threshold value registered in advance, and determines that bubbles are present when a predetermined number or more of pixels exceeding the threshold value continue.

  When it is determined that bubbles are present (ST20 is “YES”) or when reading of the model number is unsuccessful (ST10 is “NO”), the process proceeds to an abnormal process (not shown).

  The first image G1 and the second image G2 are obtained by imaging the bottle bottom 11 of the same bottle 10, but the protrusion 16 of the second image G2 depends on the illumination conditions at the time of imaging. The portion where the protrusion is reflected is shifted from the portion where the protrusion 16 of the first image G1 is reflected, and the white pixel region representing the protrusion 16 in the binary image G2 ′ of the second image G2 also reflects the shift. There is a possibility that the binary image G1 ′ of G1 deviates from the black pixel region representing the outline of the protrusion 16. As described with reference to FIG. 15, in this embodiment, the black pixel area representing the information read from the binary image G1 ′ of the first image G1 is expanded in the width direction, and is represented by the expanded black pixel area. Since the mask data is created using the entire image area as a mask area, the white pixel area representing the protrusion 16 in the binary image G2 ′ is slightly shifted from the black pixel area representing the protrusion in the binary image G1 ′. Even in this case, the entire image of the protrusion 16 including the shifted portion can be included in the mask region. Therefore, the white pixel indicating the protrusion 16 is not measured in the bubble detection process in ST18, and only the white pixel representing the peripheral portion of the bubble is measured. Therefore, in ST19, the presence / absence of the bubble can be correctly determined. it can.

In the above-described embodiment, it has been described that only the process of reading the information indicated by the protrusion 16 is performed on the binary image G1 ′ of the first image G1, but the mask processing unit 77 and the defect after the reading process are performed. By operating the detection unit 78, a defect detection process may be performed by setting a mask region based on the mask data created by the mask data creation unit 76 for the binary image G1 ′ of the first image G1. . In this case, the determination unit 79 integrates the defect detection result for the binary image G1 ′ of the first image G1 and the defect detection result for the binary image G2 ′ of the second image G2, and determines the presence or absence of the defect. To do.
In addition, the defect detected by the process with respect to the 2nd image G2 'of the 2nd image G2 is not restricted to a bubble, The melting | fusing abnormal location etc. of glass can also be detected.

DESCRIPTION OF SYMBOLS 1 Bottle bottom inspection apparatus 2 Positioning mechanism 3 1st illumination device 4 2nd illumination device 5 Camera 6 Controller 7 Image processing apparatus 10 Bottle 11 Bottle bottom 73 Character recognition process part 74 Number recognition process part 75 Code recognition process part 76 Mask Data creation unit 77 Mask processing unit 78 Defect detection unit 79 Judgment unit L1 Illumination light L2 Illumination light X Bubble LX Bubble outline

Claims (2)

  A bottle bottom inspection device for inspecting a bottle whose predetermined information is displayed on the bottom of the bottle so that it rises or is recessed from the surface of the bottle bottom, and faces the bottom of the bottle to be inspected. A first illuminating device that irradiates illumination light from a position; a second illuminating device that irradiates illumination light from a position deviating from the facing position of the bottle bottom of the bottle to be inspected; and the inspection A camera that images the bottom of the bottle of interest; a first image generated by the camera under illumination by the first illumination device; and a second image generated by the camera under illumination by the second illumination device. And an image processing device that performs image processing for inspecting the bottom of the bottle using an image, and the image processing device includes a raised portion or a recessed portion from the surface of the bottle bottom from the first image. Detect and detect Reading means for reading predetermined information displayed on the bottom of the bottle based on the pattern of the portion, and generating mask data in which the portion detected by the reading means of the information read by the reading means is a mask area A bottle bottom inspection apparatus comprising: mask data creation means; and defect detection means for setting a mask area based on the mask data in the second image and detecting a defect image from an image area excluding the mask area.   2. The mask data creating unit is configured to create mask data in which a contour of a portion detected by the reading unit is expanded in a width direction, and an image region represented by the expanded contour is used as a mask region. Bottle bottom inspection device.

Images