JP2003072791A - Metal lid with screw for metal container with screw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal lid with a screw with improved hermetic properties of a joint between a metal can in which a liquid with a high inner pressure such as a carbonated beverage is enclosed and the metal lid. SOLUTION: Curl processing is performed on an opening part of the metal can with a screw molded of a metal sheet and a plug-shaped projection with a tapered or a circular arc-like section is similarly formed by pressing or drawing on the inside of the top side of the metal lid molded of the metal sheet and it is constituted in such a way that the plug-shaped projection is relatively screwed and pressed into the opening part by a driving torque of the screw.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal lid with a screw (hereinafter, referred to as a metal lid with a screw for enhancing the airtightness of a metal container with a screw (hereinafter referred to as an aluminum can with a screw), in which a liquid such as a carbonated beverage having a high internal pressure is enclosed. The aluminum cover with a screw) is particularly suitable for application when drawing / press molding from a thin metal plate.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a cross-sectional view of a conventional aluminum can with a screw, 1 is an aluminum can, 2 is a screw part of a can,
3 is a curl portion, 4 is an aluminum lid, 5 is a lid screw portion, and 6 is a locking ring portion. For example, the mouth of a curled aluminum can 1 is a lid 4 having a substantially flat bottom (top side) as shown by a thick line, and a flat surface formed by the propulsion torque due to the twisting of the aluminum can screw portion 2 and the lid screw portion 5. It is sealed only by pressing on the opening.

The locking ring portion 6 is separated from the lid at the time of opening the lid with a slit portion formed in the lid as a boundary so that it can be seen that the lid has been opened, or the lid cannot be accidentally removed due to vibration or contact. First, the contents are filled, and after the aluminum lid 4 is tightened, the aluminum can 1 is bent so as to be wound around the ring-shaped protrusion below the screw portion.

FIG. 7 is a sectional view of another conventional example. The difference from FIG. 6 is that the can mouth is folded back by a hemming bending process, not by a curl process. In FIG. 7, a gap is provided between the folded plates for easy understanding, but in the actual case, the plates are bent in close contact.

In the case where a conventional fruit juice beverage is stored in the conventional can, the structure of the aluminum can 1 and the aluminum lid 4 does not cause liquid leakage and is not a problem. When a beverage that generates gas, such as carbonated beverages, is added, the gas will be generated over time and the internal pressure will rise, so the pressure inside the container will cause bending of parts such as screws on the container and lid. However, there is a problem in that the material is deformed / extended due to creep, and a gap is formed between the opening of the aluminum can 1 and the aluminum lid 4, and even if the gap is not enough to cause liquid leakage, the gas escapes and the quality deteriorates.

In order to solve these conventional problems, the airtightness of the container and the lid may be increased. However, as the purpose of increasing the airtightness, (1) JP-A-7-101456 (with a sealing cap) Container) and (2) JP 2000-30
A technique as disclosed in Japanese Patent No. 9364 (seal cap) has been proposed.

In the above (1), an annular step portion, a pressing corner portion, and a tapered pressing portion are formed on the inner circumference of the thick wall portion of the cap in a synthetic resin container having an outer or outer cross-sectional shape that is angular or tapered. The mouth is deformed toward the center by the taper-shaped pressing part by the screw fitting of the cap, and the upper end surface of the mouth is pressed by the pressing corner part provided on the annular step, and the elasticity of the synthetic resin is used to make two positions. It is to be sealed with. The above (2) is
It is a metal or resin cap that has a taper on the outside of the tip of the protected part and keeps airtightness by screw fitting, and the inner peripheral part of the cap that abuts the taper part when screw fitting is arcuate or tapered. A ring-shaped projection is provided on the cross section of the above, and the tapered portion at the tip of the protected portion is pressed and deformed by this projection to maintain airtightness.

The present invention relates to the shape of a lid having a substantially uniform wall thickness, which is formed by pressing or deep drawing from a thin metal plate, and the mouth portion has higher rigidity than the lid side due to curling or bending. Inside the mouth of the metal container, screw the plug-shaped projection that is formed on the top side of the lid and has a tapered or substantially arcuate cross section, or screw the outside of the can mouth to the lid that has an inversely tapered cross section. The airtightness is maintained without deforming. On the other hand, both of the above two techniques are airtight by deforming the other side (main body side) with the tapered part and the pressing corner part, the arc or the ring-shaped protrusion on the tapered part provided inside the thick part of the lid. The effect is different from that of the present invention.

[0009]

SUMMARY OF THE INVENTION According to the present invention, when a liquid having a high internal pressure is put in a conventional container composed of an aluminum can and a lid as described above, the quality of the contents is deteriorated due to the formation of a gap. It is an attempt to solve a problem.

[0010]

DISCLOSURE OF THE INVENTION The present invention solves the problems associated with the conventional container structure described above and proposes a structure of an aluminum can lid that can maintain the quality of a liquid whose internal pressure rises. In the present invention, in the relative relationship between the mouth and the lid of the aluminum can, by covering the aluminum can with the aluminum lid and twisting, there is a plug-like protrusion having a tapered or substantially arc-shaped cross section inside the mouth of the aluminum can. It has a structure capable of enhancing airtightness by screwing or by screwing the outside of the can into a lid having a reverse tapered cross section.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. FIG. 1 shows a first embodiment according to the present invention, in which 1 is an aluminum can, 2 is a can screw portion, 3
Is a curl portion, 4a is an aluminum lid, 5 is a lid screw portion, 6 is a locking ring portion, and 7 is a tapered surface portion. In the aluminum lid 4a according to the present embodiment, a plug-like projection having a tapered cross section is formed on the bottom (or the top side) by pressing or drawing, and the plug-like projection is formed on the aluminum can mouth. It is inserted in the curled portion 3 that is formed, and the can screw portion 2 and the lid screw portion 5 are inserted.
It is screwed and press-fitted by the twisting of and the propulsion torque by the screw.

After filling the contents, the aluminum lid 4a is put on the aluminum can 1 and screwed in, and the aluminum can 1 is bent so that the locking ring 6 is wound around the ring-shaped projection below the screw. The locking ring portion 6 is separated from the lid at the time of opening the lid with a slit portion formed in the lid as a boundary so that it can be known that the lid has been opened, or the lid does not come off accidentally due to vibration or contact. To do.

Since the aluminum can and the aluminum lid are constructed as described above, a taper-shaped stopper is formed by twisting and propelling torque of the screw instead of simply pressing the flat portion of the aluminum lid into the mouth of the aluminum can as in the conventional product. Since it is screwed into the can mouth, the air tightness of the can and the lid is greatly improved. Therefore, even if a content such as a carbonated beverage having a high internal pressure is filled, it is possible to obtain the effect that the initial quality can be maintained for a long period of time without being let out. Further, by coating or applying resin on at least the tapered surface 7 of the lid 4a, the aluminum surface of the lid and the opening can be protected from scratches caused by rubbing, and the contact force due to the screw-in / press-fit is further increased by the elasticity of the resin. The effect that it can be enhanced is obtained. Further, since the lid has substantially the same wall thickness, there is no wasteful material, and there is an effect that resources can be saved and material and processing costs can be reduced.

Example 2. 2 shows a second embodiment according to the present invention, only the structure of the lid 4b is different from that of the first embodiment, and the names and reference numerals of the respective parts are the same, so the description of the respective parts will be omitted. Only the features of the lid will be described. In this embodiment, the inner side of the aluminum lid 4b on the top side is formed in a substantially hemispherical shape (the cross section is a substantially arcuate shape), and the contact portion with the can mouth is the lateral portion of the hemispherical body. It is similar to the embodiment.

Example 3. FIG. 3 shows a third embodiment according to the present invention, but only the structure of the lid 4c is different from that of the first embodiment, and the names and reference numerals of the respective parts are the same, so the description of the respective parts will be omitted. Only the features of the lid will be described. In this embodiment, the upper side (short side) of the trapezoidal shape of the inner side of the aluminum lid 4c is formed in a substantially hemispherical shape to the outer side of the top side, and contact with the can is made at the sloped portion of the plug-like projection. The function and effect are similar to those of the first embodiment, but there is an effect that the rigidity of the lid can be increased.

Example 4. 4 is a fourth embodiment according to the present invention, only the structure of the lid 4d is different from the first embodiment, the names and reference numerals of each part are the same, so the description of each part will be omitted, Only the features of the lid will be described. In the present embodiment, the aluminum lid 4d has a U-shaped folded-back inner cylindrical projection formed on the top side, and the outer surface of the lid bottom is formed into a substantially flat or convex shape. Although there is a gap in the folded-back portion in FIG. 4, it is actually processed so as to be in close contact. Also in this embodiment, the contact with the can mouth is made on the outer surface of the tapered projection on the bottom of the lid. The function and effect are similar to those of the first embodiment, but the rigidity of the lid is further increased, and
Since there is no recess in the upper portion of the lid 4d, there is an effect that water and dust do not collect in the recess unlike the lids of the first to third embodiments.

Embodiment 5. FIG. 5 shows a fifth embodiment according to the present invention, in which 1 is an aluminum can, 2 is a can screw portion, 3 is a curl portion, 4e is an aluminum lid, 5 is a lid screw portion, 6 is a locking ring portion, and 7 is It is a tapered surface portion. The aluminum lid 4e according to the present embodiment has a substantially trapezoidal (reverse taper) cross-section as shown by a thick line, and the aluminum can mouth is covered with a cap-shaped lid having a reverse taper surface extending from the top side to the opening side. When is twisted, the can screw portion 2 and the lid screw portion 5 are twisted, and the propelling torque by the screw acts so that the can mouth is relatively screwed in and pressed into the lid.

After the contents are filled, the aluminum lid 4e is put on the aluminum can 1 and screwed in, and bending is performed so that the locking ring part 6 is wound around the ring-shaped protrusion below the screw part of the aluminum can 1. The locking ring portion 6 is separated from the lid at the time of opening the lid with a slit portion formed in the lid as a boundary so that it can be known that the lid has been opened, or the lid does not come off accidentally due to vibration or contact. To do.

Since the aluminum can and the aluminum lid are constructed as described above, a cap having a reverse taper by twisting and propelling torque of the screw is used instead of simply pressing the flat portion of the aluminum lid to the mouth of the aluminum can as in the conventional product. Since the can mouth is screwed into, the airtightness of the can and lid is greatly improved. Therefore, even if a content such as a carbonated beverage having a high internal pressure is filled, it is possible to obtain the effect that the initial quality can be maintained for a long period of time without being let out. Further, since the lid has substantially the same wall thickness, there is no wasteful material, and there is an effect that resources can be saved and material and processing costs can be reduced.

[0020]

[Other Embodiments] In the above embodiments, aluminum is used as the material of the container and the lid, but aluminum alloy, magnesium alloy, iron, etc.
It is needless to say that a metal thin plate material that is malleable and capable of deep drawing and bending can be used, and the same effect can be obtained.

[0021]

According to the first aspect of the present invention, in a metal container with a screw and a metal lid with a screw for closing the container opening with a metal lid with a screw that is screwed onto the screw, the metal container with the screw is attached to the opening of the metal container. Since a plug-shaped protrusion with a tapered cross-section was molded on the inside of the top of the metal lid that touches it, the taper-shaped stopper can be screwed into the can mouth by twisting the screw and propelling torque of the screw, thus making the can and lid airtight. The properties are remarkably improved, and there is an effect that the quality of the filler having a high internal pressure can be maintained for a long period of time. Further, since the lid has substantially the same wall thickness, there is no wasteful material, and there is an effect that resources can be saved and material and processing costs can be reduced.

According to the second invention, a metal container with a screw,
In a metal lid with a screw that closes the container opening with a metal lid with a screw that engages with this screw, a projection with a substantially arc-shaped cross section is molded inside the top of the metal lid that abuts the opening of the metal container. ,
By screwing the lid into the can mouth, it is possible to screw a nearly spherical stopper into the can mouth by twisting and propelling torque of the screw, so the airtightness of the can and the lid is significantly improved, and the quality of the filling that raises the internal pressure increases for a long time. The effect is that it can be sustained. Further, since the lid has substantially the same wall thickness, there is no wasteful material, and there is an effect that resources can be saved and material and processing costs can be reduced.

According to the third invention, a metal container with a screw,
In a metal lid with a screw that closes the container opening with a metal lid with a screw that is screwed into this screw, a cylindrical projection with a tapered cross-section is formed inside the top of the metal lid that abuts the opening of the metal container.
Moreover, since the top side outside of the metal lid is formed so as to be substantially flush with the top side of the lid or convex, the taper-shaped stopper can be screwed into the can mouth by twisting the lid and propelling torque of the screw. Further, the airtightness of the lid is remarkably improved, and the quality of the filling material having a high internal pressure can be maintained for a long time. Further, since the lid has substantially the same wall thickness, there is no wasteful material, and there is an effect that resources can be saved and material and processing costs can be reduced.

According to the fourth invention, a metal container with a screw,
In a metal lid with a screw that closes the container opening with a metal lid with a screw that engages with this screw, the abutting part of the metal lid that abuts the opening of the metal container is directed from the top side of the metal lid toward the opening side. Since it is molded in a reverse taper shape that expands, the can mouth can be screwed into the cap that has a reverse taper by twisting the screw and propelling torque of the screw by screwing the lid, so the airtightness of the can and the lid is significantly improved, There is an effect that the quality of the high filling material can be maintained for a long period of time. Further, since the lid has substantially the same wall thickness, there is no wasteful material, and there is an effect that resources can be saved and material and processing costs can be reduced.

According to the fifth aspect of the invention, since at least the tapered surface or the curved surface of the lid, which abuts the container opening, is coated or coated with resin, the aluminum surface of the lid and the opening can be protected from scratches caused by rubbing. At the same time, the elastic force of the resin can further enhance the contact force due to the screw-in / press-in, improve the gas escape preventing force, and maintain the initial quality of the filler for a long time. Further, since the lid has substantially the same wall thickness, there is no wasteful material, and there is an effect that resources can be saved and material and processing costs can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an aluminum can and a lid showing a first embodiment of the present invention.

FIG. 2 is a sectional view of an aluminum can and a lid showing a second embodiment of the present invention.

FIG. 3 is a sectional view of an aluminum can and a lid showing a third embodiment of the present invention.

FIG. 4 is a sectional view of an aluminum can and a lid showing a fourth embodiment of the present invention.

FIG. 5 is a sectional view of an aluminum can and a lid showing a fifth embodiment of the present invention.

FIG. 6 is a sectional view of an aluminum can and a lid showing a conventional example.

FIG. 7 is a sectional view of an aluminum can and a lid showing another conventional example.

[Explanation of symbols]

1 aluminum can 2 Can screw part 3 Curl part 3b Bent section 4 Conventional aluminum lid 4a-4e Aluminum lid according to the present invention 5 Cap screw part 6 Locking ring part 7 Tapered surface

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3E084 AA04 AA12 AA23 AB01 BA01                       CA01 CC02 DA01 DB12 DC02                       EA03 EC02 FA09 FB02 GA04                       GB04

Claims (5)

[Claims] 1. A metal lid formed from a thin metal plate for closing a container opening with a metal lid screwed to a screw of a metal container with a screw, the metal lid being in contact with the opening of the metal container. On the inside of the top side, a projection with a tapered cross section is formed,
A screw-equipped metal lid for a screw-equipped metal container, characterized in that the plug-shaped projection is screwed into the container mouth. 2. A metal lid formed from a thin metal plate for covering a container opening with a metal lid screwed to a screw of a screwed metal container, the metal lid being in contact with the opening of the metal container. A threaded metal lid for a metal container with a screw, characterized in that a plug-shaped projection having an arc-shaped cross section is formed on the inner side of the top side, and the plug-shaped projection is screwed into a container opening. 3. A metal lid formed from a thin metal plate for covering a container opening with a metal lid screwed to a screw of a metal container with a screw, the metal lid being in contact with the opening of the metal container. A cylindrical protrusion with a tapered cross section is formed on the inside of the top side, and the outside of the top side of the metal lid is formed to be substantially flush with the periphery of the top side of the lid or a convex shape, and the tapered cylindrical protrusion is screwed into the container mouth. A screw-equipped metal lid for a screw-equipped metal container characterized by being configured. 4. A metal lid formed from a thin metal plate for covering a container opening with a metal lid screwed to a screw of a metal container with a screw, the metal lid being in contact with the opening of the metal container. A metal lid with a screw for a metal container, characterized in that the contact portion is formed in a reverse taper shape expanding from the top side of the lid toward the opening side, and the container opening is screwed into the reverse taper lid. . 5. The screwed metal lid according to claim 1, wherein a resin is coated or applied on a contact portion of the metal lid with the opening of the metal container.