JP2023053343A - Method for inspecting glass bottle, method for manufacturing glass bottle, and device for inspecting glass bottle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for automatically determining absence/presence of defects in glass bottles with engraved surfaces.

SOLUTION: Provided is a method for inspecting a glass bottle with an engraved surface. In step S12, a set of images constituted of a predetermined number of images are acquired by imaging a glass bottle with an area sensor camera, while rotating around a central axis of the glass bottle. In step S16, a first image in which at least a part of a glass bottle located at a reference position in a rotation direction is imaged, is selected from the set of images. In step S18, a pre-image imaged a predetermined number before the first image, and a post-image imaged a predetermined number after the first image, are selected from the set of images. In steps S20 and S30, presence/absence of defects is determined on the basis of the first image, the pre-image, and the post-image. The pre-image and the post-image respectively include a pattern corresponding to at least a part of a first pattern.

SELECTED DRAWING: Figure 4

COPYRIGHT: (C)2023,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to a method for inspecting a glass bottle having an engraving on its surface, a method for manufacturing a glass bottle, and an inspection apparatus for a glass bottle.

BACKGROUND ART A glass bottle having an uneven surface and a sculpture is known. Glass bottles with engravings have originality and a sense of luxury, and give a favorable impression to consumers.

For example, Patent Document 1 has been proposed as a method for inspecting a glass bottle having an uneven surface. In the invention of Patent Document 1, a carved surface with unevenness and a smooth surface without unevenness are optically determined.

JP-A-58-216906

However, in the invention of Patent Document 1, it is only possible to determine whether the surface has unevenness or not, and the defect of the glass bottle cannot be inspected. When trying to optically inspect a glass bottle with unevenness, it is difficult to determine whether the dark area is due to unevenness or a dark area due to defects such as scratches or bubbles. Even now, the presence or absence of flaws such as scratches and bubbles in glass bottles with unevenness depends solely on visual inspection.

Accordingly, the present invention provides an inspection method, a glass bottle manufacturing method, and an inspection apparatus for automatically determining the presence or absence of a defect in a glass bottle having an engraving on its surface from an image.

The present invention has been made to solve at least part of the above problems, and can be implemented as the following aspects or application examples.

In the following explanation, "sculpture" refers to the design of unevenness on the surface of the glass bottle, and "pattern" refers to changes in light and dark density caused by the "sculpture" that appears in the image obtained by imaging the glass bottle. is.

[1] One aspect of the glass bottle inspection method according to the present invention is
A method for inspecting a glass bottle having an engraving on its surface, comprising:
obtaining an image group consisting of a predetermined number of images by imaging the glass bottle with an area sensor camera while rotating the glass bottle around the central axis;
selecting from the image group a first image in which at least part of the glass bottle located at a reference position in the rotational direction is captured;
a step of selecting, from the image group, a previous image captured a predetermined number of times before the first image and a post-image captured a predetermined number after the first image;
determining whether there is a defect based on the first image, the previous image, and the after image;
The reference position is set in advance at a position where a first pattern corresponding to at least part of the engraving is imaged in the first image,
The before image and the after image each include a pattern corresponding to at least part of the first pattern.

By rotating the glass bottle, images are taken at different angles, so even if the same engraving is taken, the appearance of the pattern differs for each image taken at different angles. This is because the engraving is the unevenness on the surface of the glass bottle, so depending on the angle at which the image is taken, the pattern may appear dark or may appear bright enough to be hardly recognized as a pattern. Also, even if there is no engraving on the surface being imaged, the engraving on the back may be imaged through the bottle. Therefore, according to one aspect of the glass bottle inspection method, at least a part of the first pattern imaged in the first image can be inspected redundantly by the images before and after the imaged at different angles. Misjudgment of a pattern as a defect can be suppressed. Thus, according to one aspect of the glass bottle inspection method, the presence or absence of a defect can be automatically determined from the image.

[2] In one aspect of the glass bottle inspection method,
The body of the glass bottle has a substantially rectangular cross-sectional shape,
The step of selecting the first image may select the first image in which the glass bottle in the reference position is imaged based on the width of the body portion imaged in the image.

According to one aspect of the glass bottle inspection method, the first image at the reference position can be easily selected if the body portion is substantially rectangular.

[3] In one aspect of the glass bottle inspection method,
The reference position is a position where the width of the torso in the image is the minimum,
In the first image, the front part of the torso is imaged,
In the front image, a front corner portion forward in the rotational direction with respect to the front portion is imaged,
In the rear image, a rear corner portion behind the front portion in the rotational direction may be imaged.

Compared to the front portion, the corner portion of the glass bottle has a greater change in brightness due to changes in the wall thickness of the bottle, and is a portion that is difficult to inspect using an image. According to one aspect of the glass bottle inspection method, the pattern corresponding to the first pattern is redundantly inspected not only at the front face but also at the front and back corners, so defects can be determined more reliably.

[4] One aspect of the glass bottle inspection method according to the present invention is
A method for inspecting a glass bottle having an engraving on its surface, comprising:
obtaining an image group consisting of a predetermined number of images by imaging the glass bottle with an area sensor camera while rotating the glass bottle around the central axis;
selecting from the group of images a first image in which a first pattern corresponding to at least part of the engraving is captured;
setting an inspection gate prepared in advance in the first image, and determining whether or not there is a defect in the inspection gate;
including
The inspection gate includes a first inspection gate for inspecting the first pattern and a second inspection gate for inspecting a region other than the first pattern,
Different inspections are performed by the first inspection gate and the second inspection gate.

According to one aspect of the glass bottle inspection method, by performing different inspections for the first pattern and other areas, the detection accuracy of defects can be improved, so the presence or absence of defects can be automatically determined from the image. .

[5] In one aspect of the glass bottle inspection method,
The selecting step further selects a second image in which a pattern corresponding to at least part of the first pattern is captured at a different angle from the first image in the direction of rotation of the glass bottle,
In the determining step, different inspections can be performed on the first inspection gate and the second inspection gate prepared in advance corresponding to the second image.

According to one aspect of the glass bottle inspection method, since at least a part of the first pattern captured in the first image can be inspected redundantly by images captured at different angles, the engraving pattern is regarded as a defect. Misjudgment can be suppressed, and inspection accuracy is improved.

[6] One aspect of the method for manufacturing a glass bottle according to the present invention is
A parison is formed from a gob with a rough mold, the parison is formed with a finishing mold into a glass bottle having an engraving on the surface, and the glass bottle is subjected to the above glass bottle inspection method to determine that there are no defects. Characterized by getting a bottle.

According to one aspect of the method for manufacturing a glass bottle, defects can be automatically determined even for a glass bottle having an engraving, so that a glass bottle without defects can be manufactured.

[7] One aspect of the glass bottle inspection apparatus according to the present invention is
An inspection device for glass bottles having engravings on their surface, comprising:
The inspection device is
a rotation mechanism that rotates the glass bottle around a central axis;
an area sensor camera that captures an image of the rotating glass bottle;
a storage unit that stores an image group consisting of a predetermined number of images captured by the area sensor camera;
a first image in which at least a part of the glass bottle located at a reference position in the rotation direction is captured is selected from the image group, and a previous image captured a predetermined number before the first image; a selection unit that selects a post-image captured after a predetermined number of times from the image;
a determining unit that determines whether or not there is a defect based on the first image, the previous image, and the subsequent image selected by the selecting unit;
including
The reference position is set in advance at a position where a first pattern corresponding to at least part of the engraving is imaged in the first image,
The before image and the after image each include a pattern corresponding to at least part of the first pattern.

According to one aspect of the glass bottle inspection apparatus, at least a part of the first pattern imaged in the first image can be inspected redundantly by images taken before and after the images taken at different angles, so that the pattern by engraving can be inspected. It is possible to suppress erroneous determination as a defect. Thus, according to one aspect of the glass bottle inspection apparatus, the presence or absence of a defect can be automatically determined from the image.

[8] One aspect of the glass bottle inspection apparatus according to the present invention is
An inspection device for glass bottles having engravings on their surface, comprising:
The inspection device is
a rotation mechanism that rotates the glass bottle around a central axis;
an area sensor camera that captures an image of the rotating glass bottle;
a storage unit that stores a predetermined number of image groups captured by the area sensor camera;
a selection unit that selects from the image group a first image in which a first pattern corresponding to at least part of the engraving is captured;
a determination unit that sets an inspection gate prepared in advance in the first image and determines whether or not there is a defect in the inspection gate;
including
The inspection gate includes a first inspection gate for inspecting the first pattern and a second inspection gate for inspecting a region other than the first pattern,
Different inspections are performed by the first inspection gate and the second inspection gate.

According to one aspect of the glass bottle inspection apparatus, by performing different inspections for the first pattern and other areas, the detection accuracy of defects can be improved, so the presence or absence of defects can be automatically determined from the image. .

[9] In one aspect of the glass bottle inspection device,
The inspection device includes a mounting table on which the glass bottle is placed and which rotates around a rotation axis, a pressing member that presses the opening of the glass bottle on the mounting table from above, and a rotation angle of the mounting table. a detection mechanism for
The area sensor camera captures an image at each predetermined angle based on the rotation angle signal from the detection mechanism,
the mounting table has a plurality of grooves extending radially from the rotating shaft,
The pressing member may have a flat surface that contacts the end surface of the mouth, and an annular wall that surrounds the flat surface and contacts the side surface of the mouth.

According to one aspect of the glass bottle inspection apparatus, by suppressing the glass bottle from slipping on the mounting table, the image of the glass bottle at each predetermined angle can be captured more accurately. Further, according to one aspect of the glass bottle inspection apparatus, the flat surface and the annular wall can suppress the inclination of the glass bottle, and the inclination of the glass bottle in the image can be suppressed, so that the inspection accuracy can be improved.

According to one aspect of the glass bottle inspection method according to the present invention, even a glass bottle having an engraving on its surface can be automatically inspected with high accuracy. Further, according to one aspect of the glass bottle inspection apparatus according to the present invention, even glass bottles having engravings on their surfaces can be automatically inspected with high accuracy.

It is a top view of an inspection device concerning this embodiment. It is a side view which shows a holding member and a mounting base typically. It is a top view of a mounting base. It is a flow chart of the inspection method concerning this embodiment. It is a schematic diagram explaining the process to select. It is a schematic diagram explaining an inspection gate. It is a schematic diagram explaining an inspection gate.

Preferred embodiments of the present invention will be described in detail below with reference to the drawings. It should be noted that the embodiments described below do not unduly limit the scope of the invention described in the claims. Moreover, not all the configurations described below are essential constituent elements of the present invention.

A glass bottle inspection apparatus according to the present embodiment is an inspection apparatus for a glass bottle having an engraving on its surface, and the inspection apparatus includes a rotation mechanism for rotating the glass bottle around a central axis, and a rotation mechanism for rotating the glass bottle. an area sensor camera that captures an image of the bottle; a storage unit that stores an image group consisting of a predetermined number of images captured by the area sensor camera; a selection unit that selects a first image from the image group, and selects a previous image captured a predetermined number of times before the first image and a post-image captured a predetermined number after the first image; and a determination unit that determines whether or not there is a defect based on the first image, the previous image, and the after image selected by the selection unit, wherein the reference position is the engraving on the first image. A first pattern corresponding to at least a part of the first pattern is set in advance, and the front image and the back image each include a pattern corresponding to at least a part of the first pattern.

A glass bottle inspection apparatus according to the present embodiment is an inspection apparatus for a glass bottle having an engraving on its surface, and the inspection apparatus includes a rotation mechanism for rotating the glass bottle around a central axis, and a rotation mechanism for rotating the glass bottle. an area sensor camera that captures an image of a bottle; a storage unit that stores a predetermined number of image groups captured by the area sensor camera; a selection unit that selects from a group; and a determination unit that sets an inspection gate prepared in advance in the first image and determines whether or not there is a defect in the inspection gate, wherein the inspection gate is the first pattern. and a second inspection gate for inspecting a region other than the first pattern, wherein different inspections are performed by the first inspection gate and the second inspection gate.

1. Inspection Apparatus An inspection apparatus 1 for glass bottles 10 will be described in detail with reference to FIGS. 1 to 3. FIG. 1 is a plan view of an inspection apparatus 1 according to this embodiment, FIG. 2 is a side view schematically showing a pressing member 32 and a mounting table 30, and FIG. 3 is a plan view of the mounting table 30. FIG. 2 and 3 show the imaging unit 40 as an area sensor camera 42, and the pressing member 32 in FIG. 2 is shown in longitudinal section.

The inspection device 1 shown in FIGS. 1-3 is for a glass bottle 10 having an engraving 16 (see FIG. 2) on its surface. The inspection apparatus 1 is incorporated as a part of the production line of the glass bottles 10 , and the glass bottles 10 that have been formed and annealed are introduced into the inspection apparatus 1 from the supply section 90 , and the glass bottles 10 after inspection are delivered to the discharge section 96 . to the next process. The inspection device 1 includes a rotating mechanism, an area sensor camera 42 , a storage section 54 , a selection section 51 and a determination section 52 . In the rotating mechanism of the present embodiment, a part of the conveying device for the glass bottles 10 and the rotation driving device 34 cooperate with each other. It may be a mechanism for rotating the bottle 10 . Also, in this embodiment, an example in which the storage unit 54 and the like are included in the control unit 50 of the inspection apparatus 1 will be described, but they may be provided separately from the control unit 50 of the inspection apparatus 1 .

The glass bottle 10 is made of glass and is transparent or translucent. Translucency is a degree of transparency that allows the light from the light-emitting part 20 transmitted through the glass bottle 10 to determine the bubbles inside. The body portion 14 of the glass bottle 10 has a substantially rectangular cross section. Here, the substantially rectangular shape includes squares and rectangles, and also includes bottles with curved corners, which are generally called rectangular bottles. The cross-sectional shape of the glass bottle 10 may be circular or polygonal other than square. Glass bottle 10 has engravings on its surface. The engraving is unevenness formed on the surface of the glass bottle 10, and is formed by, for example, unevenness carved on the surface of the mold during molding. The engraving, for example, has a width of 0.2 mm or more and a depth or protrusion height of 0.03 mm or more and 2.0 mm or less.

A center axis 12 is a virtual line indicating a rotation center axis around which the glass bottle 10 supported by the mounting table 30 and the pressing member 32 rotates. The central axis 12 coincides with the center of the inner peripheral circle in the cross section of the mouth portion 13 of the glass bottle 10 .

The inspection apparatus 1 is a transmitted light type inspection apparatus 1 that captures an image with an imaging unit 40 using light transmitted through the glass bottle 10 and detects a black portion in the captured image as a defect in the glass bottle 10. . The disadvantage is that the light from the light emitting section 20 is randomly reflected or refracted, and the amount of light that reaches the imaging section 40 is extremely small compared to the other portions (body section 14 with no detection object). Therefore, the part with the defect is darker than other parts, and appears as a black defect on the glass bottle 10 in the image. In addition, since there is also a dark portion due to the engraving 16, it is required not to erroneously judge this as a defect.

A reference line 41 is a virtual line that connects the imaging unit 40 and the central axis 12 . The imaging unit 40 can image the glass bottle 10 with the reference line 41 as the center. The reference line 41 coincides with the optical axis of the camera that extends from the imaging section 40 toward the central axis 12 of the glass bottle 10 . Since the imaging unit 40 also follows the movement of the glass bottle 10, the reference line 41 also moves. In an intermittent transport inspection apparatus, the imaging unit 40 is fixed at a predetermined position, so the reference line 41 is always at the same position.

1-1. Conveying Device As shown in FIG. 1 , the inspection device 1 includes an annular conveying device 92 . The conveying device 92 continuously conveys the glass bottles 10 and does not stop even at the inspection position. A light-emitting unit 20 that illuminates the glass bottle 10 and an imaging unit 40 that faces the light-emitting unit 20 with the glass bottle 10 interposed therebetween are arranged at predetermined positions of the conveying device 92 .

The glass bottles 10 are sequentially fed from the upstream finishing mold and slow cooling furnace to the conveying device 92 via the feeding unit 90, and the inspected glass bottles 10 are sequentially discharged from the conveying device 92 and conveyed downstream.

The conveying device 92 conveys the glass bottle 10 while supporting it rotatably about the rotating shaft 31 of the mounting table 30 by the mounting table 30 and the pressing member 32 shown in FIG. Therefore, the glass bottle 10 rotates about the central axis 12 and the rotating shaft 31 while revolving around the outer circumference of the conveying device 92 .

The conveying device 92 revolves the glass bottles 10 by transmitting the driving force of the revolving driving device 95 to the rotating shaft 93 via the belt 94 . The belt 94 and the revolution driving device 95 are arranged in a machine base (not shown) of the inspection device 1 . The revolution driving device 95 is directly or indirectly provided with a first rotation detection section 55 a that detects the movement angle of the glass bottle 10 on the conveying path and outputs it to the control section 50 .

The conveying device 92 includes a rotating mechanism that rotates the vial 10 around the central axis 12 . The rotation mechanism includes a belt 35 stretched along the transport path between a rotation driving device 34 and a pulley 36 . By driving the rotation driving device 34, the glass bottle 10 is rotated. The belt 35, the rotation driving device 34, and the like are arranged in the machine base of the inspection device 1. As shown in FIG. The belt 35 is directly or indirectly connected to the mounting table 30 supporting the glass bottle 10, and the driving force of the driving device 34 for rotation is transmitted. A second rotation detector 55 b is in contact with the belt 35 , detects the movement angle of the belt 35 by the rotation driving device 34 , and outputs it to the controller 50 . The control unit 50 calculates the rotation angle of the glass bottle 10 based on the output signals of the first rotation detection unit 55a and the second rotation detection unit 55b.

The first rotation detection section 55a and the second rotation detection section 55b may be any device capable of detecting the amount of rotation, and may be rotary encoders, for example. When the conveying device 92 rotates intermittently, the controller 50 calculates the rotation angle of the glass bottle 10 based on the output of the second rotation detector 55b at the stop position (inspection position) of the glass bottle 10 .

The conveying device 92 includes a mounting table 30 on which the glass bottle 10 is placed and which rotates around a rotating shaft 31 , a pressing member 32 which presses the opening 13 of the glass bottle 10 on the mounting table 30 from above, and the mounting table 30 . a detection mechanism for detecting the rotation angle. The detection mechanism in this embodiment is the first rotation detection section 55a and the second rotation detection section 55b. The mounting table 30 and the pressing member 32 are preferably made of resin, but may be made of metal.

As shown in FIG. 3, the mounting table 30 has a plurality of grooves 30a radially extending from the rotating shaft 31. As shown in FIG. A knurling (not shown) provided on the bottom portion 15 of the glass bottle 10 is engaged with the groove 30a to suppress the glass bottle from slipping on the mounting table. As a result, an image of the glass bottle 10 at each predetermined angle can be captured more accurately.

The pressing member 32 has a flat surface 32a that contacts the end surface of the mouth portion 13 of the glass bottle 10, and an annular wall 32b that contacts the side surface of the mouth portion 13 around the flat surface 32a. The flat surface 32a suppresses inclination of the glass bottle 10 by making surface contact with the end surface of the mouth portion 13 . The annular wall 32b restrains the tilting of the vial by contacting the sides of the mouth. By suppressing the inclination of the glass bottle 10, the inclination of the glass bottle in the image can be suppressed, so that the center axis 12 of the glass bottle 10 in the image is always constant, and the inspection accuracy can be improved. The annular wall 32b has a tapered inner surface that expands downward. The annular wall 32 b guides the mouth portion 13 to a predetermined position with its tapered inner surface when descending toward the mouth portion 13 . Depending on the shape of the mouth portion 13, the inner surface of the annular wall 32b may extend vertically instead of being tapered.

1-2. Control Unit The control unit 50 includes a selection unit 51 , a determination unit 52 , an image processing unit 53 and a storage unit 54 . The control unit 50 includes, for example, a storage device such as a CPU (Central Processing Unit), HDD (Hard Disk Drive), SSD (Solid State Drive), ROM (Read-Only Memory), RAM (Random Access Memory), a keyboard, and a mouse. , an input device such as a touch pad, and a display device such as a liquid crystal display and an organic EL (Electro Luminescence) display. The control unit 50 executes a process in which the inspection apparatus 1 conveys the glass bottle 10 at a predetermined speed and a process in which the glass bottle 10 is inspected. The control unit 50 for inspecting the glass bottles 10 may be provided separately from the control unit for conveying the glass bottles 10 .

The storage unit 54 stores an image group consisting of a predetermined number of images captured by the area sensor camera 42 of the imaging unit 40 . The group of images obtained by imaging one glass bottle 10 is preferably an image obtained by imaging at least one round or more of the glass bottle 10, for example, about 1.33 rounds (480°) or more of the glass bottle 10. is an image corresponding to A group of images obtained by imaging one glass bottle 10 is affected by the image processing capability of a CPU or the like in addition to the conveying speed and rotation speed. It is an image captured at every angle of 1° or more and 5° or less. For example, when the glass bottle 10 is imaged at 480° every 2.5° rotation angle, an image group consisting of 192 images per glass bottle 10 is stored in the storage unit 54 .

The selection unit 51 selects an image in which at least part of the glass bottle 10 is captured from the image group stored in the storage unit 54 . Each image always captures a predetermined position of the glass bottle 10 . "At least part" of the glass bottle 10 is a portion to be inspected, and the entire glass bottle 10 does not necessarily need to be imaged. The image preferably captures the entire torso 14 .

The determination unit 52 determines whether or not there is a defect based on the image selected by the selection unit 51 . Defects determined by the determining unit 52 include, for example, bubbles inside the glass bottle 10, surface bubbles on the surface of the glass bottle 10, carbon stains, white stones/foreign matter, and the like. The determination unit 52 preferably determines bubbles and surface bubbles with a diameter of 1.5 mm or more as defects. Moreover, it is preferable that the determination unit 52 does not erroneously determine the pattern in the image caused by the engraving 16 as a defect.

The control unit 50 outputs the determination result of the determination unit 52 for each glass bottle 10 and, for example, excludes the glass bottles 10 determined to have defects on the line after the discharge unit 96 . Specific processing in the control unit 50 will be described in "2. Inspection method" below.

1-3. Imaging Unit and Light Emitting Unit As shown in FIGS. 1 and 2, the imaging unit 40 is arranged to face the light emitting unit 20 with the glass bottle 10 interposed therebetween. The imaging unit 40 is arranged on a reference line 41 passing through the central axis 12 of the glass bottle 10 . The imaging unit 40 can image at least the portion of the glass bottle 10 to be inspected, and is arranged so that the entire glass bottle 10 is within the field of view of the imaging unit 40 here.

The imaging unit 40 includes an area sensor camera 42 and a tracking mirror 44 for imaging the rotating glass bottle 10 . The imaging unit 40 can capture an image in which the light from the light emitting unit 20 is transmitted through the glass bottle 10 . A CCD image sensor, a CMOS image sensor, or the like can be used as the area sensor camera 42 .

The tracking mirror 44 is for following the movement of the glass bottle 10 and taking an image of the glass bottle 10 . An area sensor camera 42 with a tracking mirror 44 is disclosed in Japanese Patent Application Laid-Open No. 2004-279222. The tracking mirror 44 rotates following the glass bottle 10 conveyed on the outer circumference of the conveying device 92 by a motor (not shown). Due to this rotation, the reference line 41 (which coincides with the optical axis of the camera) connecting the central axis 12 and the imaging unit 40 follows the movement of the vial 10 due to the rotation of the tracking mirror 44 . The deflection angle of the tracking mirror 44 is calculated so that the control section 50 predicts the next imaging position based on the output of the first rotation detection section 55a and images the glass bottle 10 at the predicted imaging position. do. The controller 50 drives the motor of the tracking mirror 44 based on the calculated deflection angle. Then, the area sensor camera 42 images the glass bottle 10 at the predicted imaging position of the glass bottle 10 . In addition, the area sensor camera 42 captures an image of the glass bottle 10 at each predetermined angle based on rotation angle signals from the first rotation detection unit 55a and the second rotation detection unit 55b. The area sensor camera 42 outputs captured image data to the control unit 50 .

The light emitting part 20 is a light source that illuminates the glass bottle 10 . The light emitting unit 20 is a surface light source capable of illuminating the glass bottle 10 from the opposite side of the imaging unit 40 . The light emitting unit 20 is set to a size that can illuminate the entire glass bottle 10, which is the largest size to be inspected by the inspection apparatus 1. As shown in FIG. The light emitting unit 20 may be capable of partially emitting light.

The front surface of the light emitting part 20 on the side of the glass bottle 10 has a rectangular shape, and almost the entire front surface serves as a light emitting surface. The light emitting unit 20 faces the glass bottle 10 and the imaging unit 40 and is arranged so that the light transmitted through the glass bottle 10 reaches the imaging unit 40 .

A known light source such as an LED or an organic EL can be used as the light source of the light emitting unit 20 . The light-emitting part 20 is a diffused illumination, and when LEDs are used, a diffusion plate can be placed in front of the light source to irradiate the glass bottle 10 with uniform light. A known diffusion plate that diffuses light from a light source such as an LED and emits it to the outside can be used as the diffusion plate. By diffusing the light with the diffuser plate, it is possible to reduce the unevenness between the portions where the light sources are not present when a large number of light sources are used.

2. Manufacturing method In the method for manufacturing a glass bottle according to the present embodiment, a parison is formed from a gob with a rough mold, the parison is formed into a glass bottle with a finishing mold, and the glass bottle is subjected to the glass bottle inspection method described later. It is characterized by obtaining a glass bottle that has been determined to be free of defects.

A glass bottle is first molded into a parison from a gob in a rough mold. The parison is molded into a cylindrical shape with a bottom by blowing compressed air into a hot gob placed in a rough mold. A plunger may be used instead of compressed air. Next, the parison is transferred to a finishing mold, and compressed air is blown into the parison within the finishing mold to mold a glass bottle as a product. Since the temperature of the glass bottle immediately after molding is high, it is slowly cooled in a slow cooling furnace. The following inspection method is performed on the glass bottles coming out of the lehr. A glass bottle judged to have no defects by executing the following inspection method is a non-defective product.

3. Inspection Method The inspection method for a glass bottle according to the first embodiment is a method for inspecting a glass bottle having an engraving on its surface, wherein the glass bottle is rotated around a central axis while the glass bottle is scanned by an area sensor camera. obtaining an image group consisting of a predetermined number of images by imaging; selecting from the image group a first image in which at least a portion of the glass bottle located at a reference position in the rotation direction is captured; selecting from the image group a previous image taken a predetermined number of times before the first image and a post-image taken a predetermined number after the first image, the first image, the previous image, and the and determining whether or not there is a defect based on the post-image, wherein the reference position is set in advance to a position where a first pattern corresponding to at least part of the engraving is imaged in the first image, and The front image and the back image each include a pattern corresponding to at least part of the first pattern.

A glass bottle inspection method according to a second embodiment is a method for inspecting a glass bottle having an engraving on its surface, wherein an image of the glass bottle is captured by an area sensor camera while rotating the glass bottle around a central axis. a step of acquiring an image group consisting of a predetermined number of images by using the above; a step of selecting a first image in which a first pattern corresponding to at least a part of the engraving is captured from the image group; setting an inspection gate prepared in advance and determining whether or not there is a defect in the inspection gate, wherein the inspection gate includes a first inspection gate for inspecting the first pattern, and a first inspection gate for inspecting the pattern other than the first pattern. and a second inspection gate for inspecting the region, wherein different inspections are performed by the first inspection gate and the second inspection gate.

3-1. First Embodiment A method for inspecting a glass bottle 10 according to a first embodiment using the inspection apparatus 1 shown in FIGS. 1 to 3 will be described with reference to FIGS. 4 to 6. FIG. FIG. 4 is a flowchart of the inspection method according to the present embodiment, FIG. 5 is a schematic diagram explaining the selection steps (S16, S18), and FIG. FIG. 6 omits the top and bottom of the image, and schematically shows (a) the front image 100, (b) the first image 101, and (c) the rear image 102 in the order in which they were picked up.

As shown in FIG. 4, the inspection method according to the first embodiment is a method for inspecting a glass bottle 10 having an engraving on its surface. It includes a step S16, a step S18 of selecting a front image and a back image from an image group, and steps S20 and S30 of determining whether or not there is a defect. The inspection method according to the first embodiment may further include a step S10 of starting imaging before S12, may include a step S14 of detecting the reference position after S12, and may be processed as non-defective after S20 and S30. A step S24 and a step S22, S32 of processing as a defective product may be further included. Each step will be described in order below with reference to FIGS. 1 to 3. FIG.

Step S10: The control section 50 instructs the imaging section 40 to start imaging. The image capturing unit 40 captures an image of the glass bottle 10 with the area sensor camera 42 while rotating the glass bottle 10 around the central axis 12 according to the command from the control unit 50 . At that time, the control unit 50 calculates the rotation angle of the glass bottle 10 based on the outputs from the first rotation detection unit 55a and the second rotation detection unit 55b, and rotates the entire circumference at each set angle (for example, 2.5 degrees). (for example, 480°). The captured image data is transmitted from the imaging section 40 to the control section 50 .

Step S<b>12 : The control section 50 acquires an image group consisting of a predetermined number of images transmitted from the imaging section 40 . An image group is a plurality of images grouped for each glass bottle 10 . The image group includes, for example, 192 images. The storage unit 54 temporarily stores, for example, an image group including a predetermined number of images captured by the area sensor camera 42 .

S<b>14 : The control unit 50 detects the reference position from the images in the image group stored in the storage unit 54 . The image group includes images captured by the imaging unit 40 at intervals of 2.5°, for example, as shown in FIG. The reference position is set in advance at a position where the first pattern 71 corresponding to at least part of the engraving 16 is imaged in the first image 101 as shown in FIG.

The reference position can be appropriately set depending on the target glass bottle 10 , and in particular, is set according to the position of the engraving 16 on the glass bottle 10 . The body portion 14 of the glass bottle 10 shown in FIG. 5 has a substantially rectangular cross-sectional shape, and has an engraving 16 on the front portion 14a. In this example, the reference position is set as the front portion 14a with the engraving 16 (the rotation angle is 0°). Although illustration is omitted, the engravings 16 are provided on all four sides, and any of the sides may be used as the front portion 14a. The images captured at −15°, 0°, and +15° in FIG. 5 correspond to the front image 100, first image 101, and rear image 102 shown in FIG. 6, respectively. The control unit 50 detects the reference position of the glass bottle 10 based on the width D of the body 14 captured in the image in the storage unit 54 . Since the trunk portion 14 is substantially rectangular, a change in the rotation angle appears as a difference in the width D in the image, so that the reference position can be easily detected. As shown in FIG. 5, the reference position where the front portion 14a faces the area sensor camera 42 is the position where the width D of the body portion 14 in the image is the smallest. The width D is determined by the control unit 50 detecting the edges 86, 86 at both ends of the body 14 due to a sudden change in the contrast density between the body 14 and the background in the front image 100, the first image 101, and the back image 102, for example. . The controller 50 calculates the distance between the edges 86, 86 as the width D, and detects that the glass bottle 10 in the first image 101 for which the smallest width D is calculated is at the reference position.

Step S16: The selection unit 51 selects the first image 101 in which at least part of the glass bottle 10 at the reference position in the rotation direction R is captured from the image group.

A step S16 of selecting the first image 101 shown in FIG. 6 selects the first image 101 detected by the control unit 50 as being in the reference position based on the width D of the body portion 14 in step S14. In FIG. 6, the selection unit 51 selects the first image 101 for which the smallest width D is calculated as the image in which the glass bottle 10 is at the reference position.

As shown in FIG. 6, in the first image 101, the front portion 14a of the body portion 14 is imaged. Even if the cross section of the torso 14 is not rectangular, it is sufficient if the first image 101 at the reference position can be selected. For example, if the horizontal end of the first pattern 71 can be detected, the distance from either one of the edges 86, 86 at both ends of the body portion 14 to the end of the first pattern 71 at the reference position is detected. A first image 101 may be selected.

In the first image 101, the front part 14a at the center and the front corner part 14b and the rear corner part 14c near the edges 86, 86 at both ends of the body part 14 are imaged. The first image 101 is in a state where the rotation angle of FIG. 5 is 0°, and mainly captures the range indicated by the thick dashed line.

In the first image 101, all the engravings 16 that can be imaged at the reference position need not be imaged as the first pattern 71, and the first pattern 71 that corresponds to at least part of the engravings 16 that can be imaged at the reference position is imaged. It is good if there is Since the light from the light emitting unit 20 is diffused by the engraving 16 and there is a portion where the change in brightness is so small that it cannot be recognized as a pattern in the image, the first pattern 71 is imaged so as to correspond to at least a part of the engraving 16. Just do it. Further, when there is a sculpture 16 on the back side of the front portion 14a, it may be reflected in the image.

Step S18: The selection unit 51 selects the images stored in the storage unit 54 from the previous image 100 captured a predetermined number of times before the first image 101 and the post-image 102 captured a predetermined number of times after the first image 101. Select from the group. In FIGS. 5 and 6, the previous image 100 is an image captured six frames before (-15°) the first image 101, and mainly captures the range indicated by the thick dashed line. A subsequent image 102 is an image captured six frames (+15°) after the first image 101, and mainly captures the range indicated by the thick dashed line. In the front image 100, the front corner portion 14b ahead in the rotational direction R with respect to the front portion 14a is imaged. In the rear image 102, the rear corner portion 14c behind the front portion 14a in the rotational direction R is imaged.

Furthermore, although not shown in FIG. 6, it is possible to select a second image, a third image and a fourth image at another reference position (S16), and select a front image and a back image for each image. (S18). Then, steps S20 to S32, which will be described later, can be similarly performed. In this way, the judgment unit 52 judges whether or not there is a defect with respect to other reference positions, that is, the remaining surfaces (back surface and left and right side surfaces) other than the front surface 14a when the cross section of the trunk 14 is square. can be done.

Step S<b>20 : The determination unit 52 determines the presence or absence of the defect E based on the first image 101 selected by the selection unit 51 . If it is determined that the defect E is present in the first image 101, the control section 50 executes step S22. When determining that there is no defect E in the first image 101, the control section 50 executes step S23.

Step S<b>30 : The determination unit 52 determines the presence or absence of the defect E based on the front image 100 and the rear image 102 . If it is determined that the defect E is present in the pre-image 100 or the post-image 102, the control section 50 executes step S32. If it is determined that there is no defect E in the pre-image 100 or the post-image 102, the control section 50 executes step S23.

The front image 100 and the rear image 102 respectively include patterns 71 a and 71 b corresponding to at least part of the first pattern 71 . Since the first pattern 71 and the patterns 71a and 71b are different in angle at which the light from the light emitting part 20 strikes the engraving 16, the contrast density changes, and the dark part that appears as the first pattern 71 appears bright in the patterns 71a and 71b. do. The "predetermined number" from the first image 101 is preferably set to an angle at which the pattern appears brighter than the reference position by checking how the pattern appears in the group of images taken in advance before inspection. As a result, it becomes easier to determine whether it is a pattern or a defect in the first image 101 in the front image 100 or the back image 102 depending on the shape of the engraving 16 . For example, the front corner 14b and the rear corner 14c of the glass bottle 10, which has a substantially square cross section, have a greater change in brightness due to changes in the thickness of the bottle compared to the front part 14a, and are difficult to inspect by image. Since the patterns 71a and 71b are inspected redundantly using front and rear images with different rotation angles, the defect E can be determined more reliably.

Steps S22 and S32: The control unit 50 executes steps S22 and S32 for treating the glass bottle 10 determined to have the defect E as a defective product. For example, the control unit 50 attaches identification data as a defective product to the glass bottle 10, and discharges the glass bottle 10 from a defective product discharging unit (not shown) provided on the downstream conveying path.

Step S23: If it is determined in steps S20 and S30 that there is no defect E, the control unit 50 determines that there is no defect E in all images, and executes step S24. In this way, at least part of the first pattern 71 captured in the first image 101 can be inspected redundantly by the front image 100 and the back image 102 captured at different angles, so that the pattern formed by the engraving 16 can be detected as the defect E. erroneous determination can be suppressed. To give a specific example, as in the first image 101 of FIG. In some cases, it may be difficult to determine whether it is a part or not. However, in some cases, the defect E appears dark in the previous image 100 and can be determined to be the defect E clearly. Therefore, since erroneous determination can be suppressed, the presence or absence of the defect E can be automatically determined from the image.

Step S24: The control unit 50 treats the glass bottle 10 judged to have no defect E as a non-defective product. For example, the inspection and packing of the next process (not shown) provided on the downstream conveying path of the inspection apparatus 1 are executed.

3-2. Second Embodiment A method for inspecting a glass bottle 10 according to a second embodiment using the inspection apparatus 1 shown in FIGS. 1 to 3 will be described with reference to FIGS. 4 to 7. FIG. FIG. 7 is a schematic diagram for explaining the inspection gate 80. As shown in FIG.

As shown in FIG. 4, the inspection method according to the second embodiment executes steps S10 to S14, S20, and S24 in the same manner as the inspection method according to the first embodiment. The inspection method according to the second embodiment may further perform steps S18, S30 and S23. In the following description, description of the same steps as those of the inspection method according to the first embodiment will be omitted.

S<b>16 : The selection unit 51 selects the first image 101 in which the first pattern 71 corresponding to at least part of the engraving 16 is captured from the image group stored in the storage unit 54 . Step S20 is performed on the image selected in step S16. Step S18 may or may not be performed. When step S18 is not executed, if it is determined in step S20 that there is no defect E in the first image 101, step S23 is omitted and step S24 is executed.

S20: The determination unit 52 sets an inspection gate 80 prepared in advance in the first image 101 and determines whether or not there is a defect E within the inspection gate 80 .

The inspection gates 80 include a first inspection gate 81 that inspects the first pattern 71 and a second inspection gate 82 that inspects areas other than the first pattern 71 . The determination unit 52 performs different inspections for the first inspection gate 81 and the second inspection gate 82 . When the determination unit 52 determines that there is no defect E as a result of the determination in the first inspection gate 81 and the second inspection gate 82, the control unit 50 executes S24. By performing different inspections for the first pattern 71 and other areas, the detection accuracy of the defect E can be improved. In FIG. 6, the first inspection gate 81 is surrounded by the second inspection gate 82 . That is, as shown in FIG. 7, the second inspection gate 82 is an area excluding the first inspection gate 81 .

The first inspection gate 81 performs inspection with lower sensitivity than the second inspection gate 82 . For example, as a criterion for the determination unit 52, a change in brightness density, for example, a threshold value for luminance can be set. In this case, the luminance threshold value of the first inspection gate 81 is set lower than that of the second inspection gate 82 . Since the first inspection gate 81 is set in the area where the first pattern 71 appears, if the threshold value is set to a high brightness, the dark portion due to the first pattern 71 will also be erroneously determined as the defect E. be.

The second inspection gate 82 is preset in a relatively wide range within the first image 101 so as to include at least part of the first pattern 71 .

The first inspection gate 81 is set by the operator using an actually captured image so as to overlap the first pattern 71 of the glass bottle 10 at the reference position. For example, the operator can use paint-based image editing software to create a different layer as the first inspection gate 81 on which lines are drawn so as to overlap the first pattern 71 . The thickness of the line of the first inspection gate 81 can be made thicker than that of the first pattern 71, for example, in order to suppress erroneous determination.

The image processing unit 53 can perform known image processing to extract a detection object that is a dark portion of the image selected by the selection unit 51 before the determination by the determination unit 52 is performed. Known image processing includes binarization processing, dilation, erosion, BottomHat (dark emphasis), TopHat (bright emphasis), Average (smoothing), and the like. The image processing unit 53 may change the gradation threshold for binarization between the first inspection gate 81 and the second inspection gate 82 .

S18: The selection unit 51 selects, for example, the previous image 100 as a second image in which the pattern 71a corresponding to at least part of the first pattern 71 is captured at an angle different from the first image 101 in the rotation direction R of the glass bottle 10. may be further selected. A post-image 102 may be further selected in the same manner as in the inspection method according to the first embodiment.

S30: The determination unit 52 performs different inspections using the first inspection gate 81 and the second inspection gate 82 prepared in advance corresponding to the previous image 100 as the second image. Since at least a part of the first pattern 71 imaged in the first image 101 can be inspected redundantly by the images imaged at different angles, erroneous determination of the pattern by the engraving 16 as the defect E can be suppressed and inspection can be performed. Improves accuracy.

The present invention is not limited to the above-described embodiments, and various modifications are possible, including substantially the same configurations as those described in the embodiments. Here, the "same configuration" means a configuration with the same function, method, and result, or a configuration with the same purpose and effect. Moreover, the present invention includes configurations in which non-essential portions of the configurations described in the embodiments are replaced. In addition, the present invention includes a configuration that achieves the same effects or achieves the same purpose as the configurations described in the embodiments. In addition, the present invention includes configurations obtained by adding known techniques to the configurations described in the embodiments.

DESCRIPTION OF SYMBOLS 1... Inspection apparatus, 10... Glass bottle, 12... Center shaft, 13... Mouth part, 14... Body part, 14a... Front part, 14b... Front corner part, 14c... Rear corner part, 15... Bottom part, 16... Engraving, DESCRIPTION OF SYMBOLS 20... Light-emitting part 22... Light-emitting area 30... Mounting base 30a... Groove 31... Rotating shaft 32... Pressing member 32a... Flat surface 32b... Annular wall 34... Driving device for rotation 35... Belt, 36... pulley, 40... imaging unit, 41... reference line, 42... area sensor camera, 44... tracking mirror, 50... control unit, 51... selection unit, 52... determination unit, 53... image processing unit, 54... storage unit , 55a... First rotation detector, 55b... Second rotation detector, 71... First pattern, 71a... Pattern, 71b... Pattern, 80... Inspection gate, 81... First inspection gate, 82... Second inspection gate, 86... Edge, 90... Supply unit, 92... Conveying device, 93... Rotating shaft, 94... Belt, 95... Revolving drive unit, 96... Discharge unit, 100... Front image, 101... First image, 102... Rear image , D...width, E...defect, R...rotational direction

[ 1 ] One aspect of the glass bottle inspection method according to the present invention is
A method for inspecting a glass bottle having an engraving on its surface, comprising:
obtaining an image group consisting of a predetermined number of images by imaging the glass bottle with an area sensor camera while rotating the glass bottle around the central axis;
selecting from the group of images a first image in which a first pattern corresponding to at least part of the engraving is captured;
setting an inspection gate prepared in advance in the first image, and determining whether or not there is a defect in the inspection gate;
including
The inspection gate includes a first inspection gate for inspecting the first pattern and a second inspection gate for inspecting a region other than the first pattern,
Different inspections are performed by the first inspection gate and the second inspection gate.

[ 2 ] In one aspect of the glass bottle inspection method,
The selecting step further selects a second image in which a pattern corresponding to at least part of the first pattern is captured at a different angle from the first image in the direction of rotation of the glass bottle,
In the determining step, different inspections can be performed on the first inspection gate and the second inspection gate prepared in advance corresponding to the second image.

[ 3 ] One aspect of the method for manufacturing a glass bottle according to the present invention is
A parison is formed from a gob with a rough mold, the parison is formed with a finishing mold into a glass bottle having an engraving on the surface, and the glass bottle is subjected to the above glass bottle inspection method to determine that there are no defects. Characterized by getting a bottle.

[ 4 ] One aspect of the glass bottle inspection device according to the present invention is
An inspection device for glass bottles having engravings on their surface, comprising:
The inspection device is
a rotation mechanism that rotates the glass bottle around a central axis;
an area sensor camera that captures an image of the rotating glass bottle;
a storage unit that stores a predetermined number of image groups captured by the area sensor camera;
a selection unit that selects from the image group a first image in which a first pattern corresponding to at least part of the engraving is captured;
a determination unit that sets an inspection gate prepared in advance in the first image and determines whether or not there is a defect in the inspection gate;
including
The inspection gate includes a first inspection gate for inspecting the first pattern and a second inspection gate for inspecting a region other than the first pattern,
Different inspections are performed by the first inspection gate and the second inspection gate.

[ 5 ] In one aspect of the glass bottle inspection device,
The inspection device includes a mounting table on which the glass bottle is placed and which rotates around a rotation axis, a pressing member that presses the opening of the glass bottle on the mounting table from above, and a rotation angle of the mounting table. a detection mechanism for
The area sensor camera captures an image at each predetermined angle based on the rotation angle signal from the detection mechanism,
the mounting table has a plurality of grooves extending radially from the rotating shaft,
The pressing member may have a flat surface that contacts the end surface of the mouth, and an annular wall that surrounds the flat surface and contacts the side surface of the mouth.

Claims (9)

A method for inspecting a glass bottle having an engraving on its surface, comprising:
obtaining an image group consisting of a predetermined number of images by imaging the glass bottle with an area sensor camera while rotating the glass bottle around the central axis;
selecting from the image group a first image in which at least part of the glass bottle located at a reference position in the rotational direction is captured;
a step of selecting, from the image group, a previous image captured a predetermined number of times before the first image and a post-image captured a predetermined number after the first image;
determining whether there is a defect based on the first image, the previous image, and the after image;
The reference position is set in advance at a position where a first pattern corresponding to at least part of the engraving is imaged in the first image,
A method of inspecting a glass bottle, wherein the before image and the after image each include a pattern corresponding to at least part of the first pattern. In the glass bottle inspection method according to claim 1,
The body of the glass bottle has a substantially rectangular cross-sectional shape,
The step of selecting the first image selects the first image in which the glass bottle in the reference position is imaged based on the width of the body portion imaged in the image. Bottle inspection method. In the glass bottle inspection method according to claim 2,
The reference position is a position where the width of the torso in the image is the minimum,
In the first image, the front part of the torso is imaged,
In the front image, a front corner portion forward in the rotational direction with respect to the front portion is imaged,
A method of inspecting a glass bottle, wherein the rear image is a rear corner portion behind the front portion in the rotational direction. A method for inspecting a glass bottle having an engraving on its surface, comprising:
obtaining an image group consisting of a predetermined number of images by imaging the glass bottle with an area sensor camera while rotating the glass bottle around the central axis;
selecting from the group of images a first image in which a first pattern corresponding to at least part of the engraving is captured;
setting an inspection gate prepared in advance in the first image, and determining whether or not there is a defect in the inspection gate;
including
The inspection gate includes a first inspection gate for inspecting the first pattern and a second inspection gate for inspecting a region other than the first pattern,
A method of inspecting a glass bottle, wherein different inspections are performed by the first inspection gate and the second inspection gate. In the glass bottle inspection method according to claim 4,
The selecting step further selects a second image in which a pattern corresponding to at least part of the first pattern is captured at a different angle from the first image in the direction of rotation of the glass bottle,
A method of inspecting a glass bottle, wherein in the determining step, different inspections are performed by the first inspection gate and the second inspection gate prepared in advance corresponding to the second image. A parison is molded from a gob with a rough mold, the parison is molded into a glass bottle with a finishing mold, and the glass bottle inspection method according to any one of claims 1 to 5 is performed on the glass bottle. A method for producing a glass bottle, characterized by obtaining a glass bottle judged to have no defects by An inspection device for glass bottles having engravings on their surface, comprising:
The inspection device is
a rotation mechanism that rotates the glass bottle around a central axis;
an area sensor camera that captures an image of the rotating glass bottle;
a storage unit that stores an image group consisting of a predetermined number of images captured by the area sensor camera;
a first image in which at least a part of the glass bottle located at a reference position in the rotation direction is captured is selected from the image group, and a previous image captured a predetermined number before the first image; a selection unit that selects a post-image captured after a predetermined number of times from the image;
a determining unit that determines whether or not there is a defect based on the first image, the previous image, and the subsequent image selected by the selecting unit;
including
The reference position is set in advance at a position where a first pattern corresponding to at least part of the engraving is imaged in the first image,
A glass bottle inspection apparatus, wherein the before image and the after image each include a pattern corresponding to at least a part of the first pattern. An inspection device for glass bottles having engravings on their surface, comprising:
The inspection device is
a rotation mechanism that rotates the glass bottle around a central axis;
an area sensor camera that captures an image of the rotating glass bottle;
a storage unit that stores a predetermined number of image groups captured by the area sensor camera;
a selection unit that selects from the image group a first image in which a first pattern corresponding to at least part of the engraving is captured;
a determination unit that sets an inspection gate prepared in advance in the first image and determines whether or not there is a defect in the inspection gate;
including
The inspection gate includes a first inspection gate for inspecting the first pattern and a second inspection gate for inspecting a region other than the first pattern,
An inspection apparatus for glass bottles, wherein different inspections are performed by the first inspection gate and the second inspection gate. In the glass bottle inspection device according to claim 7 or claim 8,
The inspection device includes a mounting table on which the glass bottle is placed and which rotates around a rotation axis, a pressing member that presses the opening of the glass bottle on the mounting table from above, and a rotation angle of the mounting table. a detection mechanism for
The area sensor camera captures an image at each predetermined angle based on the rotation angle signal from the detection mechanism,
the mounting table has a plurality of grooves extending radially from the rotating shaft,
The apparatus for inspecting a glass bottle, wherein the pressing member has a flat surface in contact with an end face of the mouth, and an annular wall surrounding the flat surface and in contact with a side surface of the mouth.

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