JPH1179246A - Container, method for sealing container, and sealing apparatus for container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a container having a sealable structure capable of suppressing the blow-off of content and not wrinkling or damaging a container main body in a manufacturing process, and a method and apparatus for well hermetically sealing the container having this structure. SOLUTION: When a container 10 is to be sealed, a container main body 11 and a lid 12 are held between a mold 30 and a lower mold 40. Since a pad 35 is pressed to the lid 12 at this time, the lid 12 is deformed into such a shape that the outer surface thereof is depressed and the inner surface thereof is expanded. At a point of time when the lid 12 is properly deformed, the leading end parts of an annular projection 31 and a columnar projection 32 are pressed to the outer surface of the lid 12 to fuse the container main body 11 and the lid 12. The container 10 thus sealed hermetically suppresses the pressure rise in the container 10 because the lid 12 depressed inside the container main body expands outward and content is not blown off at the time of opening.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container which is pre-filled with contents and whose opening is sealed with a film-shaped lid, and which is peeled off or broken when necessary and opened, and a container of this kind. The present invention relates to a sealing method and a sealing device for sealing a container.

[0002]

2. Description of the Related Art Conventionally, a container filled with a liquid, for example, a container filled with milk for coffee or the like, has had a problem that the contents are easily blown out when opened and spilled.
In order to deal with such a problem, conventionally, for example, Japanese Patent Application Laid-Open No. Sho 64-70306,
The container was sealed with a sealing device as disclosed in Japanese Patent Publication No. 82. The sealing device described in each of the above publications is a device that presses the container from the side and deforms the container so that the volume is reduced, and in that state, seals the opening of the container with a film-shaped lid. Since the inside of the container is decompressed with the restoration of the shape of the container body, the outside air flows into the container at the same time as the container is opened and the droplets are prevented from blowing out of the container. It was something that could be done.

[0003]

However, the container sealed by the sealing device described in each of the above publications has a drawback that the side surface of the container is apt to be wrinkled or damaged due to the fact that the side surface is pressed and sealed. In particular, when a container having a relatively low rigidity (for example, a container having a relatively small thickness) is used,
The deformation of the container is not restored until the container is opened due to the pressure difference between the inside and outside of the container, which may cause a problem that the product value is impaired due to poor appearance.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to prevent the contents from blowing out and to seal the container body without wrinkles or scratches during the manufacturing process. An object of the present invention is to provide a container having a structure, a method for sealing a container capable of sealing the container having such a structure satisfactorily, and a sealing device.

[0005]

Means for Solving the Problems and Effects of the Invention In order to achieve the above-mentioned object, a container according to claim 1 has a container body having an opening and an opening covering the opening. Wherein the lid is welded to the periphery of the opening in a state in which the lid is recessed inward of the container body and is sealed to the periphery of the opening. It is characterized by.

[0006] In this container, the film material serving as the lid is not particularly limited, and materials conventionally used in this type of container can be employed. More specifically, metal films such as aluminum, polyolefin-based materials, and the like can be used. Polyester resin films and composite multilayer films thereof can be used. Usually, a heat melting layer made of thermoplastic resin or the like is formed on the inner surface side of the lid in order to weld the lid to the container body, but as a structure in which the surface layer on the container body side is melted and welded to the lid. No problem.

When the lid is made of an elastically deformable film, the inside of the container is depressurized when a force is applied to restore the shape of the lid welded in the recessed state. As it sucks into the inside, the effect of preventing the scattering of contents is increased, but if the film material can be deformed flexibly with the increase of internal pressure and the rise in pressure can be moderated, the lid will be in a concave state It may be plastically deformed. That is, in many cases, the contents are scattered when the contents adhered to the opening start position are blown out from the inside of the high-pressure container to the outside of the low-pressure container. Even if the pressure is not reduced from the outside of the container, the inside and outside of the container may be the same pressure, and if the film is flexible enough to reduce the increase in the internal pressure, even if the lid is plastically deformed. In addition, it is possible to prevent the contents from blowing out.

Further, the container body is not particularly limited, and materials conventionally used in this type of container can be employed. More specifically, molded articles of thermoplastic resin,
Resin-coated pulp molded products can be used. According to the container configured as described above, for example, even when the contents are in a state of being expanded from the time of filling, or in a state where the side surface of the container is pressed, Since the recessed lid expands to the outside of the container body and suppresses a rise in pressure inside the container, the contents do not blow out when the container is opened.

When the opening is sealed, it is not necessary to deform the container body to perform the sealing operation. Therefore, wrinkles and scratches are not easily formed on the container body during the manufacturing process, and even if a container having relatively low rigidity is used, the container does not deform.
The opening of the container configured as described above is sealed, for example, by the method as described in claim 2. That is, the container sealing method according to claim 2 covers the opening of the container body with a film-shaped lid, and seals the lid by welding the lid to the periphery of the opening. In the above, by pressing a pad having a shape at least part of which can enter the inside of the container body from the opening, against the outer surface of the lid, the lid is deformed so that the outer surface of the lid is depressed and the inner surface expands. The lid is welded to the periphery of the opening in a state where the bulged portion enters the inside of the container body.

[0010] Here, the pad has a shape such that at least a part of the pad can enter the inside of the container body through the opening.
The specific shape is not particularly limited, but naturally, it must be deformed without breaking the lid, so the contact portion with the lid must not be sharply pointed, Desirably, the shape is such that it contacts the lid with as large an area as possible and does not apply an uneven pressure to a part of the lid.

Although the pad itself does not apply heat to the lid, since a heating element for welding the lid to the container body is present near the pad, the pad receives heat from the heating element. Is required to have heat resistance that does not deteriorate. However, if the pad is made of a material with high thermal conductivity such as a metal material even if it has heat resistance, if the pad is in direct contact with the heating element, heat from the heating element Since there is a possibility that the pad is transmitted to the lid via the cover, it is desirable to form the pad with a material having low thermal conductivity in order to prevent this. As a specific example, if a pad is made of a heat-resistant resin such as a fluorine resin, a pad having both high heat resistance and low thermal conductivity can be obtained.

According to such a sealing method, the lid is deformed along the surface of the pad, and is welded to the periphery of the opening of the container body while maintaining the deformed shape. Therefore, despite the fact that the lid itself is in the form of a film that can be flexibly deformed, the lid does not swell to the outside of the container body during welding. Therefore, it is possible to easily manufacture a container in which the lid is welded in a state where the lid is recessed inside the container body.

In sealing the opening of the container by the above-mentioned sealing method, it is convenient to use a sealing device as described in claim 3. That is, the container sealing device according to claim 3 is a device that covers the opening of the container main body with a film-shaped lid and seals the lid by welding the lid to the periphery of the opening. A mold having an annular projection having a shape adapted to the periphery of the opening is provided, and the mold is heated to push the tip of the annular projection from the outer surface of the lid toward the periphery of the opening. In the container sealing device in which the lid is welded to the periphery of the opening by being applied, the lid is disposed inside the annular projection of the mold, and the amount of projection is larger than that of the annular projection. A portion protruding from the tip portion is provided with a pad having a shape capable of entering the inside of the container body from the opening, and by pressing the pad against the outer surface of the lid, the outer surface of the lid is depressed and the inner surface is Deform the lid to swell, In a state of being penetrate the bulged portion of the inside of the container body,
At the same time, the lid is welded to the periphery of the opening by pressing the tip of the annular projection from the outer surface of the lid toward the periphery of the opening.

According to this sealing device, when the annular projection of the mold is pressed against the outer surface of the lid to perform welding of the lid, the pad disposed inside the annular projection is simultaneously pressed against the lid. Since this pad has a larger protrusion amount than the annular protrusion, it is pressed against the lid before the annular protrusion, and as a result,
The film-like lid deforms into a shape along the surface of the pad.
Then, the tip of the annular projection is pressed against the outer surface of the lid while the inner surface of the lid swelling due to the deformation has entered the opening, and the heat from the annular projection causes the lid to surround the opening of the container body. Welded to. Therefore, it is possible to easily manufacture a container in which the lid is welded in a state where the lid is recessed inside the container body.

By the way, in the container sealing device,
Since the annular protrusion of the mold is repeatedly pressed against the outer surface of the lid, it is easy for dirt to accumulate at the tip or to be partially worn away.If this is left as it is, uniform welding is performed over the entire circumference of the annular protrusion. May not be possible.
Therefore, it is usually necessary to perform maintenance of the annular projection, such as polishing and cleaning the tip of the annular projection at an appropriate timing.

However, if the pad inside the annular projection protrudes beyond the annular projection as in the sealing device described above, the pad is arranged such that the pad becomes an obstacle when polishing the annular projection. This causes a new problem that the maintenance work becomes difficult to perform.
Also, if you accidentally grind the pad,
There is a possibility that the shape of the pad may be distorted or the amount of protrusion of the pad may be too small, which may cause adverse effects.

On the other hand, a container sealing device according to a fourth aspect is characterized in that the pad is detachably attached to the mold. According to the container sealing device configured as described above, when performing maintenance of the annular protrusion, only the pad is removed from the mold, and in that state, the tip of the annular protrusion is polished, and maintenance such as cleaning is performed. After the maintenance work, the pads may be attached to the mold again. By doing so, the maintenance work is not made difficult by the pad, and the pad is not accidentally polished during the maintenance work.

Further, in the above container sealing device, the amount of protrusion of the pad is adjusted in consideration of the size of the opening, the material of the film material serving as the lid, and the like so that the amount of protrusion is optimal. It is not always easy to specify the amount of protrusion, and if several types of pads having different amounts of protrusion were created by trial and error, there would be a problem that the cost would be too high to select the pad. Further, as described above, when the annular protrusion is polished, the amount of protrusion of the annular protrusion fluctuates slightly, and therefore, unless the amount of protrusion of the pad is appropriately adjusted according to the annular protrusion, the lid may be polished. The condition of the dent may change.

On the other hand, a container sealing device according to a fifth aspect is characterized in that the pad is configured to be able to change the amount of projection of a portion projecting from the tip of the annular projection.

According to the container sealing device constructed as described above, the amount of protrusion of the pad can be adjusted to a desired amount of protrusion. Therefore, in adjusting the amount of protrusion to the optimum amount of protrusion, it is not necessary to prepare several types of pads. Also, when the amount of protrusion of the pad needs to be adjusted due to wear of the annular projection or the like, it is not necessary to replace the pad with another pad.

The specific structure of the pad is not limited as long as the pad is configured so that the amount of protrusion of the portion protruding from the tip of the annular protrusion can be changed.
For example, if the pad has a structure that screws into the mold,
The amount of protrusion can be changed by changing the degree of screwing.

[0022]

Next, an embodiment of the present invention will be described with reference to an example. At first, about container, Figure 1
This will be described with reference to FIGS. Container 10
Is a container to be filled with a liquid such as coffee milk, and is constituted by a container body 11 and a lid 12.

The container body 11 is formed by integrally molding a bottom portion 14, a body portion 15, and a flange portion 16 with a thermoplastic resin such as polystyrene. An opening portion 17 is formed on the upper surface side of the flange portion 16. . A part of the flange portion 16 is partially extended to the side to form a broken piece 19 that can be broken from the cut line 18.

The lid 12 is welded to the upper surface of the flange 16 at the first welding portion 21 and the second welding portion 22. Although not explicitly shown in the figure, the lid 12 has a three-layer structure in which a PET film, an aluminum film, and a polyester film are stacked from the outside of the container, and the polyester film inside the container and the container body 11 are welded. is there.

The first welded portion 21 is an annular portion exactly overlapping the periphery of the opening 17, and the first welded portion 21 is located at this position.
And the lid 12 are welded, so that the opening 17 is sealed with the contents L filled. Second weld 2
Reference numeral 2 denotes a portion where the lid 12 and the fragment 19 are welded.
When the broken piece 19 is separated from the second welded portion 8, the second welded portion 22
The broken piece 19 welded to the lid 12 is peeled off integrally with the lid 12, and the broken piece 19 functions as a knob to be picked by the user.

Further, as shown in FIG. 1B, the container 10 is characterized in that the lid 12 is welded to the periphery of the opening 17 with the lid 12 recessed inside the container body 11. is there. When the lid 12 having such a shape is employed, for example, the contents L and the like are in a state of being expanded more than at the time of filling,
Even when the side surface of the container body 11 is in a pressed state, the lid 12 recessed inside the container body 11
However, the contents are prevented from swelling to the outside of the container body 11 and suppressing the rise in the pressure inside the container 10, so that the contents do not blow out from the opening start position at the time of opening. Further, since the structure is such that the lid 12 is deformed and not the structure that deforms the container main body 11, it is not necessary to deform the container main body 11 and perform the sealing operation when the opening 17 is sealed. Therefore, the container main body 11 is not easily wrinkled or scratched in the manufacturing process, and the container main body 11 does not deform even when a relatively rigid container is used.

Next, a method of sealing the container 10 will be described. In the present embodiment, the opening 17 of the container 10
Is sealed using a mold 30 shown in FIGS. 2 (a) and 2 (b). The mold 30 includes an annular projection 31 and a columnar projection 32 on the lower surface side. The annular protrusion 31 is a protrusion having a shape whose tip matches the first welded portion 21 of the container 10, and the cylindrical protrusion 32 is a protrusion having a shape whose tip matches the second welded portion 22 of the container 10. is there. A recess 33 is formed inside the annular projection 31, and a screw shaft 36 protruding from a pad 35 is screwed into a screw hole 34 formed substantially in the center of the recess 33.

The pad 35 is made of a fluorine resin (fluorocarbon resin), and as shown in FIG. 2B, the pressing surface 35a at the lower end is bulged into a smooth curved surface shape corresponding to a part of a spherical surface. It is attached to the mold 30 so that the lower end position P1 projects below the lower end position P2 of the annular projection 31. However, the amount of protrusion of the pad 35 varies depending on the degree of screwing of the screw shaft 36, and can be adjusted to an arbitrary amount of protrusion by rotating the pad 35. If the pad 35 is rotated in a direction in which the screw shaft 36 is removed from the screw hole 34, the pad 35 is rotated.
And the screw shaft 36 can be removed from the mold 30.

The mold 30 configured as described above, when mounted on the sealing device, is disposed at a position facing the lower mold 40 capable of housing the container body 11, as shown in FIG. The lower mold 40 is configured to be able to ascend and descend by a hydraulic cylinder (not shown), and after the container body 11 filled with the contents L is loaded into the lower mold 40, the container body 11
The lid 12 is supplied to the upper part of the container 30 and then the lower mold 40 rises, and the container body 11 and the lid 1 are located between the mold 30 and the lower mold 40.
2 is sandwiched.

At this time, the pad 35 is pressed against the outer surface of the lid 12, and the lid 12 is deformed into a shape in which the outer surface is dented and the inner surface is expanded. The inflated portion of the inner surface of the lid 12 is located at a position where it just enters the inside of the container body 11, and with the deformation of the lid 12, some of the air above the contents L in the container 10 flows out of the container. Degassed.

When the lid 12 is appropriately deformed, the distal ends of the annular projection 31 and the columnar projection 32 are pressed against the outer surface of the lid 12. The mold 30 includes a heater (not shown).
Is heated to about 200 ° C. by the annular projection 3
1 and the columnar projection 32 are pressed against the lid 12, heat generated from the annular projection 31 and the columnar projection 32
2 and the container body 11 are welded. When the welding is completed, the lower mold 40 descends, and the sealed container 10 is taken out from the lower mold 40.

If the container 10 is hermetically sealed by the method described above, the container body 11 and the lid 12 can be welded while the outer surface of the lid 12 is dented by the pad 35.
The container 2 is not welded in a state where it is not depressed, nor is it welded in a state where it is swollen outward, and the container 10 sealed with the lid 12 in a depressed state can be easily manufactured.

An annular projection 31 and a cylindrical projection 32
It is necessary to polish or clean the tip surface of the pad at an appropriate timing because it is liable to be stained or scratched. In this case, the pad 35 can be removed. There is no problem that it is difficult to do,
The pad 35 is not erroneously polished.

Further, since the amount of protrusion of the pad 35 can be adjusted to a desired amount of protrusion, it is not necessary to prepare several types of pads for adjusting the amount of protrusion to the optimum amount of protrusion. Even when the protrusion amount of the pad 35 must be readjusted due to the cause, there is an advantage that no countermeasure such as replacement with another pad is required, and no extra cost is caused.

Although the embodiments of the present invention have been described above, various specific embodiments other than those described above are conceivable for the embodiments of the present invention.
Known materials can be appropriately used for the material of the mold and the material of the pad. Further, the shapes and dimensions of the container, the mold, and the pad can be arbitrarily set.

[Brief description of the drawings]

1A and 1B show a container according to an embodiment, wherein FIG. 1A is a plan view thereof, and FIG. 1B is a sectional view taken along line AA of FIG.

FIG. 2 shows a mold mounted on a container sealing device;
(A) is the bottom view, (b) is the BB line cut surface end view.

FIG. 3 is a longitudinal sectional end view showing a schematic structure of a main part of the container sealing device.

[Explanation of symbols]

10 ... container, 11 ... container body, 12 ... lid,
14 ... bottom part, 15 ... trunk part, 16 ... flange part, 17 ... opening part, 18 ... cut line, 19 ...
Fragment, 21 ... First welded part, 22 ... Second welded part, 30 ... Mold, 31 ... Circular projection, 32 ...
Cylindrical projection, 33 ... recess, 34 ... screw hole, 35
... pad, 35a ... pressing surface, 36 ... screw shaft, 40 ... lower mold.

Claims (5)

[Claims] 1. A container comprising: a container main body having an opening; and a film-like lid that is welded to a periphery of the opening while covering the opening, and seals the opening. A container which is welded to the periphery of the opening in a state of being recessed inside the container body. 2. A container sealing method in which an opening of a container body is covered with a film-shaped lid and the lid is welded to a peripheral edge of the opening to seal the opening, wherein at least a part of the opening is sealed. By pressing a pad having a shape capable of invading the inside of the container body from the outside onto the outer surface of the lid, the lid is deformed so that the outer surface of the lid is depressed and the inner surface is expanded, and the expanded portion is the container. A method for sealing a container, wherein the lid is welded to a periphery of the opening in a state where the lid is inserted into the inside of the main body. 3. An apparatus for covering an opening of a container body with a film-like lid and sealing the opening by welding the lid to a periphery of the opening, wherein a tip end is formed on a periphery of the opening. A mold having an annular protrusion of a suitable shape is provided,
By heating the mold and pressing the tip of the annular projection from the outer surface of the lid toward the periphery of the opening,
In the container sealing device for welding the lid to the periphery of the opening, the lid is disposed inside the annular protrusion, the protrusion amount is larger than the annular protrusion, and the protrusion amount is larger than the tip of the annular protrusion. A protruding portion is provided with a pad having a shape capable of entering the inside of the container body from the opening, and the pad is pressed against the outer surface of the lid so that the outer surface of the lid is depressed and the inner surface expands. Deform the lid,
In a state where the bulged portion has entered the inside of the container body, at the same time, by pressing the tip of the annular projection from the outer surface of the lid toward the periphery of the opening,
A sealing device for a container, wherein the lid is welded to a periphery of the opening. 4. The container sealing device according to claim 3, wherein the pad is detachably attached to the mold. 5. The container sealing device according to claim 3, wherein the pad is configured to be able to change a protrusion amount of a portion of the annular protrusion that protrudes from a tip end portion. Container sealing device.