JP2543620B2 - Defect detection method for thermal adhesive seal - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for detecting a defective heat-adhesive seal of a packaging material film in a PTP package such as a medicine package.

[Prior Art] Generally, in a PTP package such as a medicine package, the contents such as tablets are accommodated in the molding recess of the synthetic resin sheet, and the packaging of aluminum or the like is placed on the sheet so as to close the molding recess. The material film is formed as a heat-bonded seal.

As a method for detecting a defect of the heat-adhesive seal of the packaging material film in this kind of PTP packaging body or the like, for example, JP-A-62-1639
A method as disclosed in Japanese Patent Publication No. 50 is conventionally known. In this conventional method, the heat-bonding seal surface of the packaging material film is irradiated with a hole from a light projector, and the amount of light reflected from the seal surface is detected by a light receiver such as a line sensor, and the detected amount of reflected light is preset. Compare with the reference light amount,
It is designed to determine if the seal is defective.

[Problems to be Solved by the Invention] However, in the conventional detection method, even if a sealing defect large enough to lift the packaging material film can be detected, a small sealing defect such that the packaging material film does not float up can be detected. There was a problem that it could not be detected.

When a heat-adhesive seal is applied using a film material such as aluminum whose surface is a matte surface as the packaging material film, the matte surface of the packaging material film is irregularly reflected and the amount of reflected light is reduced. However, there is a problem that the quality of the seal cannot be accurately detected.

The present invention has been made by paying attention to the problems existing in such a conventional technique, and an object of the present invention is to provide a thermoadhesive seal capable of reliably detecting even a slight sealing defect. It is to provide a defect detection method.

Another object of the present invention is to provide a heat-adhesive seal for a packaging film even when the film is made of aluminum or the like having a matte surface as a packaging film and the heat-adhesion seal is applied. It is an object of the present invention to provide a method for detecting a defect of a heat-bonded seal, which can obtain a sufficient amount of reflected light from the surface and can accurately detect the quality of the seal.

[Means for Solving the Problems] In order to achieve the above object, in the invention according to claim 1, the mesh-shaped heat-bonded sealing surface of the packaging material film in the package is irradiated with laser light, and the sealing surface is irradiated. The amount of reflected light from the seal surface is detected, and when the reflected light amount is smaller than a preset value, it is determined that the seal surface is normally meshed, and when the reflected light amount is larger than the preset value, the seal surface is It is determined that the seal is defective because the mesh is not normally formed.

In the invention according to claim 2, in addition to the above-mentioned means, a multi-layer structure in which a coating layer is provided on the matte surface of a film material is used as the packaging film, and regular reflection on the surface of the resin coating layer is used. The angle of incidence of the laser light on the seal surface was set so that the ratio was 10% or more.

Further, in the invention according to claim 3, in addition to the above-mentioned means, the reflected light is further reflected by a diffusion plate, and the amount of the reflected light is detected.

[Operation] According to the invention according to claim 1, by the above means, when the mesh-shaped heat-bonding seal surface of the packaging material film in the package is irradiated with laser light, the amount of light reflected from the seal surface is detected. To be done. Since the laser light has high directivity, the amount of reflected light corresponding to the unevenness of the mesh-shaped heat-bonding seal surface is detected. When the amount of reflected light is smaller than a preset value, it is determined that the seal surface is normally meshed, and when the amount of reflected light is larger than the set value, the mesh is normally formed on the seal surface. If not, it is determined that the seal is defective.

Further, according to the invention of claim 2, even if the surface of the film material of the packaging material film is a matte surface, it is not affected by diffused reflection on the matte surface, and the heat-adhesive seal of the packaging material film is obtained. A sufficient amount of reflected light can be obtained from the surface, and the quality of the matt heat-bonded seal can be accurately detected.

Further, according to the invention of claim 3, the laser light has a high directivity as a characteristic, and the reflected light incident on the diffuser plate is also projected in a mesh shape, which can be averaged by the diffuser plate. Becomes

[Embodiment] An embodiment of the present invention will be described below in detail with reference to the drawings.

First, the structure of the medicine package as a PTP package will be described. As shown in FIGS. 3 and 4, the medicine package 1 contains contents such as tablets in a large number of molding recesses 3 provided in the synthetic resin sheet 2. The sheet 2 for accommodating the object 4 and closing the molding recess 3
The packaging material film 5 is heat-sealed on the upper side, and is separated into individual pieces by a separation line 6 such as perforations or slits. A mesh-shaped heat-bonding seal groove 7 having a predetermined depth is formed on the surface of the packaging material film 5 over the entire surface of the packaging material film except the storage portion of the content 4 by a seal roller used for heat-bonding sealing. There is.

Further, in the manufacturing process, the medicine package 1 is formed in a state in which a plurality of sheets are arranged in the width direction and continuously connected in the longitudinal direction as shown in FIG. After detecting the defect of the heat-bonding seal by the embodied seal defect detecting device, the continuous sheet-shaped medicine package 1 is cut sheet by sheet.

Further, in this embodiment, as shown in FIG. 6, as the packaging material film 5, a film material 8 such as aluminum whose surface is a matte surface 8a and a matte surface 8a of the film material 8 are provided. A multi-layer structure composed of the applied transparent resin coating layer 9 is used, and the packaging material film 5 is heat-sealed on the sheet 2 so that the resin coating layer 9 is on the front side.

Therefore, the seal defect detecting device for detecting the seal defect of the medicine package 1 will be described. As shown in FIG. 1, the continuous seal medicine package 1 is conveyed with the surface of the packaging material film 5 facing up. It is placed on a conveyor 11 such as a belt and is moved in one direction at a predetermined speed by the operation of the conveyor 11.
A light projector 12 composed of a laser head is arranged facing one side of the carrier 11 and above one side thereof, and the laser light is emitted from the light projector 12 to the sealing surface of the packaging material film 5 of the medicine package 1.

As shown in FIGS. 2 and 3, in the continuous sheet-shaped medicine package 1, generally, a sealing defect 13 occurs continuously for a predetermined length in the width direction, so that the laser light from the light projector 12 is generated. The beam 14 is formed so as to extend over a predetermined width along the seal center line 15 between the medicine packages 1 arranged in the width direction.

Further, in this embodiment, as shown in FIGS. 1 and 6, the light projector 12 is obliquely arranged with respect to the sealing surface of the packaging material film 5 and the light is transmitted to the sealing surface of the packaging material film 5. The incident angle θ is set according to the refraction angle α of light in the resin coating layer 9.

That is, as shown in FIGS. 6 and 7, when the sealing surface of the packaging material film 5 is irradiated with light, the incident light La
Is the regular reflection light Lb reflected on the surface of the resin coating layer 9.
And the refracted light Lc that is transmitted through the inside of the resin coating layer 9, and is specularly reflected light with respect to the energy of the incident light La.
The regular reflectance R as the ratio of the energy of Lb sharply increases when the incident angle θ of light is set to a predetermined value or more. Therefore, in this embodiment, the incident angle θ of light with respect to the seal surface is set so that the regular reflectance R on the surface of the resin coating layer 9 is 10% or more.

The image diffusion plate 16 is disposed on the other side of the carrier 11 so as to face the other side, and the reflected light Lb from the sealing surface of the packaging material film 5 is incident on the image diffusion plate 16 and the light is reflected. Light and dark are generated on the image diffusion plate 16 while being diffused above. When the packaging material film 5 is heat-sealed normally, a mesh-shaped heat-sealing seal groove 7 having a predetermined depth is formed on the surface of the sealing film 7.
Since irregular reflection occurs in the image diffusion plate 16, the amount of light incident on the image diffusion plate 16 decreases, and conversely, when there is a defect in the heat-bonding seal, since the seal groove 7 having a predetermined depth is not formed, irregular reflection does not occur. The amount of light incident on the image diffusion plate 16 increases.

A light receiver 17 including a television camera or the like using a line sensor or an area sensor is disposed obliquely above the image diffusion plate 16, and the light and dark on the image diffusion plate 16 is captured as an image through a lens 18, and the image is captured. To electrical signals. 8th
As shown in the figure, the central processing unit (CP
U) 19 receives a video electric signal from the light receiver 17, compares the video electric signal with a reference electric value corresponding to a preset reference light amount, and when the light amount is less than a predetermined value, it is determined as a normal seal. If the light quantity exceeds a predetermined value, it is determined that the seal is defective.

The display device 20 such as a lamp can be
It is activated by the output signal from 9 and notifies the detection status of the defective seal. The take-out device 21 uses the CPU1 when a defective seal is detected.
The medicine package 1 which is activated by the output signal from 9 and has a defective seal is cut from the continuous sheet state and then taken out from the normal line.

Next, the operation of the thermal-bonding-seal defect detecting device configured as described above will be described.

Now, in this seal defect detecting device, the carrier 11
Thus, while the continuous sealed medicine package 1 is transferred in one direction, laser light is emitted from the light projector 12 to the sealing surface of the packaging material film 5 of the medicine package 1 to detect the defect of the heat adhesive seal. At this time, when the heat-sealing of the packaging material film 5 is normally performed, the mesh-shaped heat-sealing seal groove 7 having a predetermined depth is formed on the surface thereof, and irregular reflection is caused in the seal groove 7. As a result, the amount of light incident on the image diffusion plate 16 is reduced. Therefore, the amount of light entering the light receiver 17 from the image diffusion plate 16 becomes less than or equal to a predetermined value, and the CPU 19 determines that the sealing is normally performed.

On the other hand, as shown in FIG. 5, when a sealing defect 13 occurs on the surface of the packaging material film 5, since the sealing groove 7 having a predetermined depth is not formed, diffuse reflection does not occur, so that the image The amount of light incident on the diffusion plate 16 increases. For this reason,
The amount of light entering the light receiver 17 from the image diffusion plate 16 exceeds a predetermined value, and the CPU 19 determines that a seal defect has occurred. Then, with the output signal from this CPU 19,
The display device 20 is operated to notify the seal failure, and the takeout device 21 is operated to take out the medicine package 1 having the seal failure from the normal line.

As described above, in the heat-bonding-seal defect detection device of this embodiment, the amount of light reflected from the sealing surface is predetermined in consideration of diffused reflection in the heat-bonding seal groove 7 formed on the surface of the packaging material film 5. If it is less than the value, it is judged as a normal seal
When the amount of reflected light exceeds a predetermined value, it is determined that the seal is defective. Therefore, the amount of light reflected from the sealing surface of the packaging material film 5 is determined based on a regular reference to accurately detect a defective seal. be able to.

Further, in the seal defect detecting apparatus of this embodiment, the packaging material film 5 has a multi-layer structure in which the matte surface 8a of the film material 8 is provided with the resin coating layer 9 and the resin coating layer is used. Since the incident angle θ of the light from the projector 12 to the sealing surface is set so that the regular reflectance R on the surface of 9 is 10% or more, the surface of the film material 8 of the packaging material film 5 is a matte surface. Even if it is 8a, a sufficient amount of reflected light can be obtained from the sealing surface of the packaging material film 5 without being affected by diffused reflection on the matte surface 8a. Therefore, the quality of the thermal adhesive seal can be accurately detected.

The present invention is not limited to the configuration of the above-mentioned embodiment, and for example, the projector 12, the image diffusion plate 16, and the light receiver 17 are provided.
Other configurations may be adopted as, for example, and the configurations of the respective units may be arbitrarily modified and embodied without departing from the spirit of the present invention.

[Effect of the Invention] As described in detail above, according to the invention of claim 1,
The excellent effect that even a slight sealing failure on the mesh-shaped heat-bonding sealing surface of the packaging material film can be surely detected.

Further, according to the invention of claim 2, even when a heat-adhesive seal is applied using a film material such as aluminum having a matte surface as a packaging material film, the heat of the packaging material film is improved. This has an excellent effect that a sufficient amount of reflected light can be obtained from the adhesive seal surface and the quality of the seal can be accurately detected.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a thermal adhesive seal defect detecting device in a medicine package embodying the present invention, FIG. 2 is its plan view, and FIG. 3 is an enlarged view of one sheet of medicine package. FIG. 4 is a partial cross-sectional view showing a heat-sealed seal portion of the medicine package in an enlarged manner, and FIG. 5 is a partial plan view of the medicine sheet in a continuous sheet for explaining a defective seal detection operation. FIG. 6 is an enlarged cross-sectional view showing the incident and reflected states of light in the resin coating layer of the packaging material film, and FIG. 7 is a graph showing the relationship between the incident angle of light and the regular reflectance in the resin coating layer of the packaging material film, FIG. 8 is a block diagram showing the control circuit. 1 ... Medicine package as PTP package, 5 ... Packaging material film,
8: Film material, 8a: Matte surface, 9: Resin coating layer, 12: Emitter, 17: Receiver, θ: Incident angle, R: Regular reflectance, La: Incident light, Lb ... Regular reflection light.

Claims (3)

(57) [Claims] 1. A mesh-shaped heat-sealing sealing surface of a foam material film in a package is irradiated with laser light, the amount of reflected light from the sealing surface is detected, and when the amount of reflected light is smaller than a preset value. A heat-adhesive seal that determines that the seal surface is normally meshed, and determines that the seal surface is not normally meshed when the amount of reflected light is greater than the set value and that the seal is defective. Defect detection method. 2. A film having a multi-layer structure in which a coating layer is provided on the matte surface of the film material is used as the film of the packaging material, and the regular reflectance of the resin coating layer on the surface is
The method for detecting a defect of a heat-bonded seal according to claim 1, wherein the incident angle of the laser beam with respect to the seal surface is set so as to be 10% or more. 3. The diffused plate further reflects the reflected light,
The method for detecting a defect of a heat-bonding seal according to claim 1 or 2, wherein the amount of reflected light is detected.