JPH0627045A - Sealed part inspecting method for tube container - Google Patents

Abstract

PURPOSE:To obtain a method for inspecting sealed part of a tube container having sealed end highly accurately. CONSTITUTION:Sealed part 16 of tube container 10 having sealed end of a transparent or translucent container body 14 is inspected. The container body 14 of the tube container 10 is illuminated by an illuminating light source 30 while shielding the sealed part 16 of the tube container 10 with a shield 32. The sealed part 16 is then imaged from the side opposite to the light source 30 and insufficient seal is detected from the profile of border between the container body 14 and the sealed part 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube container seal portion inspection method for inspecting a seal portion of a tube container having a sealed container body.

[0002]

2. Description of the Related Art A tube container made of a material such as polyethylene is widely used as a container for cosmetics, medicines and the like. A method of filling contents such as cosmetics and medicines into such a tube container will be described with reference to FIG. First, Fig. 1
As shown in (a), the tube container 10 is attached to the cap 12
Are supported so as to be downward, and contents such as cosmetics and chemicals are filled from the open upper end of the container body 14. next,
As shown in FIG. 1B, the upper end of the container body 14 is sandwiched by the sealing device 20 and heating or ultrasonic waves is applied. Then, as shown in FIG. 1C, the upper end portion of the container body 14 is sealed by the seal portion 16 to seal the tube container 10.

However, if the sealing by the sealing device 20 is incomplete, as shown in FIG. 1D, a so-called semi-punctured state in which the contents enter a part of the sealing portion 16 will occur. Tube container 10 closed in a semi-punctured state
When the container body 14 is externally pressurized, the contents may be squeezed out from the half punctured portion 18 of the seal portion 16, and therefore must be rejected as a defective product in advance.

Therefore, it is necessary to inspect whether or not the tube container 10 is in a semi-punctured state. In the semi-punctured tube container 10, the shape of the semi-punctured portion 18 is slightly changed when pressure is applied to the container body 14, so that the tube container 10 is conventionally used in the semi-punctured inspection process.
The pressure was applied to the inspector and the shape change was visually inspected.

[0005]

However, there is a limit to the visual inspection by the inspector, and a defective product in a semi-punctured state may be overlooked, or it may be rejected as a defective product even if it is a good product. There was a problem that it was difficult. In addition, the shape change when pressure is applied to the container body,
There is an attempt to inspect by picking up an image with an image pickup device and subjecting the picked-up image to image processing, but it is difficult to perform stable mechanical inspection because the shape change is subtle.

An object of the present invention is to provide a method for inspecting a sealed portion of a tube container, which can accurately inspect a sealing failure of a sealed portion of a tube container whose end is sealed.

[0007]

The above object is to provide a method for inspecting a seal portion of a tube container in which an end portion of a transparent or translucent container body is sealed, wherein a seal portion of the tube container is inspected. While shielding the, the container body of the tube container is illuminated by an illumination light source, the sealing portion of the tube container is imaged from the side opposite to the illumination light source, and the boundary shape between the container body and the sealing portion of the tube container is determined. This is achieved by a method for inspecting a sealed portion of a tube container, which is characterized by detecting a defective seal.

Further, the above object is to provide a method for inspecting a sealing portion of a tube container in which an end of an opaque container body is sealed, in which a illuminating light source illuminates the container body of the tube container. The sealing portion of the tube container is imaged from the side opposite to the illumination light source,
The present invention can also be achieved by a method for inspecting a seal portion of a tube container, which comprises detecting a seal defect from a boundary shape between the container body and the seal portion of the tube container.

[0009]

According to the present invention, the container body of the tube container is illuminated by the illumination light source while shielding the seal part of the tube container, and the seal part of the tube container is imaged from the side opposite to the illumination light source. The boundary between the transparent or semi-transparent container body and the seal portion can be clearly imaged to accurately detect the seal defect.

Further, according to the present invention, the container body of the tube container is illuminated by the illumination light source, and the seal portion of the tube container is imaged from the side opposite to the illumination light source. The boundary can be clearly imaged to accurately detect the seal defect.

[0011]

EXAMPLE A method for inspecting a sealed portion of a tube container according to a first example of the present invention will be described with reference to FIGS. In the present embodiment, the tube container 10 in which the container body 14 is made of a translucent or transparent material, for example, polyester.
This is the method for inspecting.

A spot type strobe illumination light source 30 is provided on the rear surface of the tube container 10 to illuminate the center of the container body 14 of the tube container 10 with strobe light. A shield plate 32 for shielding the seal portion 16 is attached to the rear surface of the tube container 10,
The illumination from the spot-type strobe illumination light source 30 is prevented from directly illuminating the seal portion 16. With the illumination in this way, from the front of the tube container 10 the CCD camera 34
The seal portion 16 of the tube container 10 is imaged by.

As described above, the spot type strobe illumination light source 30 is provided while shielding the seal portion 16 of the tube container 10.
When the container body 14 of the tube container 10 is illuminated by
The light applied to the container body 14 is diffusely reflected by the container body 14 and the contents to emit white light. On the other hand, the closely attached seal part 16 does not emit light because it is shielded by the shield plate 32. Therefore, in the image pickup screen by the CCD camera 34, as shown in FIG.
An image in which 4 emits white light and the seal portion 16 turns black is obtained. When the seal portion 16 has the half-puncture portion 18, the contents enter, so that the container body 14 emits white light.

When the contact of the tube container 10 is perfect,
As shown in FIG. 3A, the boundary between the container body 14 of the tube container 10 and the seal portion 16 is a straight line, but when the tube container 10 is in the half-punctured state, the half-punctured portion 18 also emits light, and therefore, FIG. As shown in (b), the tube container 10
Unevenness appears at the boundary between the container body 14 and the seal portion 16.

Next, an image processing method of the image pickup screen of the CCD camera 34 will be described with reference to FIG. In order to detect the unevenness of the boundary shape between the container body 14 and the seal portion 16 of the tube container 10, an inspection region having a width substantially the same as the width of the container body 14 is set. This inspection area is automatically corrected according to the captured image from the outer edge shape of the container body 14 of the captured screen and the like.

The picked-up image is scanned in the horizontal direction (the boundary direction between the container body 14 and the seal portion 16), and the image signal shown in FIG. 4A is differentiated within the designated area. The differential signal subjected to the differential processing is shown in FIG. The amount of change in the image signal is measured by performing the differential processing, and it is determined whether the state is the half-puncture state or not depending on whether the amount of change is equal to or more than a predetermined threshold value. The image signal does not change in the container body 14 because it is all white, and the image signal does not change in the seal portion 16 because it is black. Good contact is also achieved at the boundary between the container body 14 and the seal portion 16, and the image signal does not change if the boundary is a straight line as shown in FIG. However, as shown in FIG.
When 8 is present, the image signal scanned in the horizontal direction greatly changes, and the half-punctured state can be detected.

The image signal shown in FIG. 4A is an example of an image signal obtained by scanning the boundary portion between the container body 14 and the seal portion 16. In this image signal, the A portion is a narrow and sharp change portion of the image signal, and the B portion is a long change portion of the image signal. FIG. 4B shows a differential signal obtained by differentiating the image signal of FIG. In FIG. 4, since the width of the portion A is narrow, but there is a rapid change in the image signal, the differential signal exceeds the threshold value when the value is positive or negative, and a defective seal is detected. Although the width of the portion B is also wide, the image signal abruptly changes at the rising or falling, so that the differential signal exceeds the threshold value when the signal is positive or negative, and a defective seal is detected.

As described above, according to this embodiment, the boundary between the container body and the seal portion can be clearly imaged by appropriately illuminating the tube container. By differentially processing the image signal obtained by scanning the captured image in the horizontal direction, it is possible to detect the uneven shape of the boundary between the container body and the seal portion and accurately inspect the half-punctured state. A method for inspecting a seal portion of a tube container according to the second embodiment of the present invention will be described with reference to FIGS.

This embodiment is a method for inspecting the tube container 10 in which the container body 14 is made of an opaque material colored in red or the like, for example, a colored polyester material, and the opaque contents are filled. . Tube container 10
The spot type strobe illumination light source 30 is provided on the rear surface of the tube container 10 to stroboscopically illuminate the center of the container body 14 of the tube container 10 as in the first embodiment. The shielding plate 32 for shielding is not provided. With the illumination in this way, the tube container 1
0 from the front of the CCD camera 34 tube container 10
An image of the seal portion 16 of is captured.

As described above, when the spot type strobe illumination light source 30 illuminates the container body 14 of the tube container 10, the light irradiated on the container body 14 leaks from the seal portion 16 and emits white light. On the other hand, the container body 14 is shielded from light because it is made of an opaque material. Therefore, CC
On the image pickup screen of the D camera 34, as shown in FIG.
An image in which the seal portion 16 of the tube container 10 emits white light and the container body 14 is black is obtained. If the seal portion 16 has the half-puncture portion 18, the opaque contents enter, and the container body 14 becomes black like the container body 14.

When the contact of the tube container 10 is perfect,
As shown in FIG. 6A, the boundary between the container body 14 of the tube container 10 and the seal portion 16 is a straight line, but when the tube container 10 is in the half-punctured state, the half-punctured portion 18 is also shielded from light. As shown in 6 (b), the tube container 1
Unevenness appears at the boundary between the container body 14 of 0 and the seal portion 16.

Similarly to the first embodiment, the image processing method for the image pickup screen of the CCD camera 34 in this embodiment is also different from the image signal obtained by scanning the picked-up image in the horizontal direction to differentiate the container body and the seal portion. The semi-punctured state is inspected by detecting the uneven shape of the boundary of the. Thus, according to this embodiment,
By appropriately illuminating the tube container, the boundary between the container body and the seal portion of the opaque tube container can be clearly imaged.

The present invention is not limited to the above embodiment, but various modifications can be made. For example, although the spot type strobe illumination light source is used as the illumination light source in the above embodiment, it is not limited to strobe illumination, and other light sources such as halogen light and fluorescent light may be used. Further, the illumination light source may be a light source that illuminates a certain range instead of the spot type illumination.

Further, although the illumination light source which outputs visible light is used in the above-mentioned embodiment, if the shadow of the image can be detected, image pickup by X-ray or electron beam, image pickup by ultrasonic wave, image pickup by nuclear magnetic resonance. Any means may be used as long as the contents of the tube container can be imaged as a shadow image. Further, in the above embodiment, the uneven shape of the boundary between the container body and the seal portion is detected by differentiating the image signal of the captured image, but the uneven shape may be inspected by another image processing method. .

[0025]

As described above, according to the present invention, the sealing portion is shielded against the tube container of the transparent or translucent container body while the sealing portion is protected against the tube container of the opaque container body. The container body of the tube container is illuminated by the illumination light source without shielding, and the seal part of the tube container is imaged from the side opposite the illumination light source, so the boundary between the container body and the seal part is clearly imaged and sealed. It is possible to detect defects accurately.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a method of filling contents in a tube container.

FIG. 2 is an explanatory diagram of a method for inspecting a seal portion of a tube container according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a specific example of an image pickup screen by the method for inspecting a seal portion of a tube container according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of an image processing method of an image pickup screen by the method for inspecting a seal portion of a tube container according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram of a method for inspecting a seal portion of a tube container according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a specific example of an image pickup screen by a method for inspecting a seal portion of a tube container according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Tube container 12 ... Cap 14 ... Container body 16 ... Seal part 18 ... Half puncture part 20 ... Sealing device 30 ... Spot type strobe illumination light source 32 ... Shielding plate 34 ... CCD camera

Claims (2)

[Claims] 1. A method for inspecting a sealed portion of a tube container in which an end of a transparent or translucent container body is sealed, wherein a sealed portion of the tube container is shielded by an illumination light source. The container body of the tube container is illuminated, the seal portion of the tube container is imaged from the side opposite to the illumination light source, and a seal defect is detected from the boundary shape between the container body of the tube container and the seal portion. The inspection method for the seal part of the tube container. 2. A method for inspecting a sealed portion of a tube container, the end portion of an opaque container body of which is sealed, wherein a tube body of the tube container is illuminated by an illumination light source, A method for inspecting a seal part of a tube container, which comprises imaging a seal part from a side opposite to the illumination light source and detecting a seal defect from a boundary shape between the container body of the tube container and the seal part.