JP2001170730A - Mouth cap for metal container, metal container and manufacturing method for metal container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal container with a mouth cap seamed to an opening end part, which is constituted so that a using material is reduced, the container is excellent in an external appearance and sanitary in a resealed state. SOLUTION: A metal container is provided with a mouth neck part 7 to engage a mouth cap 4 with a seal cap, a skirt wall 7 connected to its one end part and having an essentially truncated conical shape, a chuck wall 9 extending from its skirt part to the direction opposite to the mouth neck part 7, an annular flat plate part 10 extending from its one end outward in the radial direction, a flange part 12 extending from its peripheral edge to a mouth neck part 4 side and a sealant 50 to be coated from the outer face of the annular flat plate part 10 over the outer face of the flange part 12. A double seam part 60, which is made by seaming the flange part 12 and the opening end part 3 of a can body 2, is folded/lapped on the outer face of the annular flat plate part 10 in the same direction to the skirt part 8 essentially.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a metal container,
In particular, the present invention relates to a metal container having a structure in which a cap is provided with a skirt wall and a sealing mouth and neck.

[0002]

2. Description of the Related Art Conventionally, there is a structure that can be resealed after once opened in a liquid canned can container containing a beverage or edible oil as a content liquid. In other words, in order to combine the advantages of a metal can, which is lightweight, excellent in cooling, and also rich in design, with the advantages of a resealable glass bottle that can be directly drunk with a mouth, 2. Description of the Related Art A so-called reseal can is known in which a mouth and neck portion engageable with a sealing cap is provided in a container, and the cap is detachably attached to the mouth and neck portion. For the reseal can, various structures have been proposed in which a mouth cover that is fixed to a metal can body has a mouth and neck portion integrally formed of a thin metal plate such as an aluminum alloy plate or a surface-treated steel plate.

[0003] For example, Japanese Patent Publication No. 10-509095 discloses a method of manufacturing a can having a neck for receiving a resealable cap, a resealable can made of hard-tempered metal and having a screw formed in the neck. Is disclosed. That is, the publication includes a can body having a drawn and ironed side wall, a bottom end wall and a neck having a diameter substantially smaller than the side wall, the neck receiving a screw cap to seal the contents into the can. Threaded aluminum cans are described.

In Japanese Utility Model Application Laid-Open No. 61-51314,
The opening end of the upper body formed by press molding from a metal plate such as an aluminum alloy plate or a tin-plated steel sheet, and the lower body provided inside thereof and formed by drawing or the like from the metal plate, and the lower body A plastic tubular body that is externally inserted into the mouth and neck of the metal bottle body joined to the opening end via an adhesive layer and the narrow mouth of the mouth and neck and has a threaded part on the outer periphery A bottle with a body is disclosed.

[0005]

However, in the structure described in Japanese Patent Application Laid-Open No. Hei 10-509095,
There were the following problems. That is, the conical lid attached to the can body is required to withstand the container internal pressure of 275 kPa to 755 kPa when filled with a content liquid such as beer or carbonated beverage, and therefore, resists deformation against buckling outward. An annular reinforcing groove (counter sink)
It is formed in the lower part of the chuck wall. Therefore, in order to reduce the thickness of the material used, that is, to reduce the weight of the container, it is necessary to further increase the depth of the annular reinforcing groove to secure strength, and accordingly the amount of material used increases, so that the intended There was a disadvantage that it was not possible to realize a lighter weight.

In the structure described in Japanese Patent Application Laid-Open Publication No. 10-509095, the appearance is inferior because the double-winding portion of the conical lid and the can body is formed so as to protrude outward. Not only that, dust, water, or the content liquid dripped at the time of pouring easily accumulates in the annular reinforcing groove, so that there is a problem that the storage becomes unsanitary when resealed and stored.

On the other hand, in the structure described in Japanese Utility Model Laid-Open Publication No. 61-51314, the upper body and the lower body are joined together by an adhesive to form the container body, so that uniform bonding over the entire circumference is achieved. Is not necessarily obtained, and the joint between the lower end of the upper body and the upper end of the lower body is not folded back in a hook shape, so it is necessary when a large container internal pressure is applied or when closing the sealing cap. As described above, the joint may possibly be deformed by the axial load applied in the axial direction.

The present invention has been made in view of the above circumstances, and provides a base and a metal container that can be used in a reduced amount of material, have a good appearance, and are hygienic even in a resealed state. The purpose is to do so.

[0009]

In order to achieve the above object, the invention described in claim 1 is a metal container which is fixedly wound around an open end of a cylindrical metal container. A mouth cap for engaging a sealing cap, a substantially frusto-conical skirt wall connected to one end of the mouth neck, and a skirt wall from the skirt of the skirt wall. A chuck wall extending in a position along the center axis and opposite to the mouth-neck portion, an annular flat plate extending radially outward from one end of the chuck wall, and the skirt wall extending from an outer peripheral edge of the annular flat plate; A flange portion extending toward the mouth and neck side in a posture along the central axis of the seal member, and a sealant is applied over a surface of the flange portion facing the chuck wall and an upper surface of the annular flat plate portion. Features A.

Therefore, according to the invention described in claim 1,
For example, when the cap is fixed to the can body, the flange portion serving as a fastening portion for the opening end of the can body protrudes in the same direction as the mouth and neck portion, and the annular flat plate portion is concave with respect to the skirt wall. Therefore, it is easy to apply the sealant, and even in the manufacturing equipment for the cap, the sealant is often applied to the inner surface of the can lid in the well-known can lid. Since a facility for reversing the above is required, such a facility can also be omitted. In addition, the radially inward tightening of the flange portion and the open end portion in the radial direction at the center axis of the skirt wall can be easily performed without damaging the sealant. In this case, the sealant for sealing the double-wound portion is not exposed to the outside of the metal container.

According to a second aspect of the present invention, there is provided a metal container provided with a metal can body having a cylindrical shape, and a mouth cap which is fixedly wound around one open end of the can body. A mouth-and-neck portion for engaging the sealing cap, a substantially frustoconical skirt wall connected to one end of the mouth-and-neck portion, and a skirt portion of the skirt wall from the skirt portion of the skirt wall. A chuck wall extending in a position along the center axis and opposite to the mouth-neck portion, an annular flat plate extending radially outward from one end of the chuck wall, and the skirt wall extending from an outer peripheral edge of the annular flat plate; A flange portion extending toward the mouth and neck portion in a posture along the central axis of the flange portion; a sealant applied over a surface of the flange portion facing the chuck wall and an outer surface of the annular flat plate portion; Part and the opening end Double seam portion formed by seaming a can, said skirt wall substantially the same inclination direction, and is characterized in that the folded over the outer surface of the annular flat plate portion.

Therefore, according to the invention described in claim 2,
The double-sealed portion is formed toward the inner peripheral side of the can body so as to have the same inclination direction as the skirt wall, so that the folded portion of the double-sealed portion protrudes as an external appearance. It does not appear in a state, and accordingly, the appearance of the whole metal container is improved. In the invention described in claim 2,
Since the double-sealed portion does not protrude outside the outer diameter of the can body, for example, even if a large number of metal containers are rubbed against each other, the double-sealed portion prevents the outer surface of the other can body from being rubbed. There is no risk of damage to the painted or printed surface.

Further, according to the second aspect of the present invention, since the folded portion in the double winding portion is formed along the skirt wall, for example, a plurality of metal containers are set upright on the conveyor belt. When transporting, there is no danger that the double wound portions will be caught and deformed, and even when the content liquid is filled from the other open end side, the double wound portion is attached to the guide member (lifter, etc.). It can be prevented from being caught. Therefore, troubles such as leakage or alteration of contents caused by loosening due to deformation of the double wound portion are prevented beforehand.

The invention described in claim 3 is the same as the claim 2.
In addition to the configuration described in the above, the bead portion protruding toward the central axis of the can body is formed on the can body so as to be along the portion closest to the outer peripheral edge of the double wound portion. It is characterized by the following.

Therefore, according to the invention described in claim 3,
The can body side wall below the folded part in the double winding part is
Since it is formed to be constricted inward, even if an excessive load is applied when the sealing cap is plugged or the like, the double winding portion is supported by the beat portion and the displacement thereof is regulated.
Therefore, it is possible to prevent a gap between the upper wall of the double wound portion and the cover hook due to an excessive load, and to maintain a good contact state.

Further, according to a fourth aspect of the present invention, there is provided a metal container comprising: a metal can body having a cylindrical shape; and a cap which is fixedly wound around one open end of the can body. In the manufacturing method, the mouth and neck for engaging the sealing cap, a substantially frustoconical skirt wall connected to one end of the mouth and neck, and the center of the skirt wall from the skirt of the skirt wall A chuck wall extending in a posture along the axis and opposite to the mouth-neck portion, an annular flat plate extending radially outward from one end of the chuck wall, and a skirt wall extending from an outer peripheral edge of the annular flat plate. A base lid including a flange portion extending toward the mouth and neck portion in a posture along a central axis, and a sealant applied over a surface of the flange portion facing the chuck wall and an upper surface of the annular flat plate portion. , The tip of the flange Is fitted to the inner periphery of the opening end in a state shifted inward in the axial direction from the tip of the opening end, and the inside of the can body is placed in a state where the opening end is put on the flange. To form a temporary tightening portion, and then press the temporary tightening portion by a male mold and a female mold having a molding surface having substantially the same inclination direction as the skirt wall, and The present invention is characterized in that a double tightening portion is formed which is folded substantially in the same inclination direction as the wall and on the outer surface of the annular flat plate portion.

Therefore, according to the manufacturing method of the fourth aspect, it is possible to easily change the overlapping width of the double-sealed portion only by changing the amount of displacement of the tip, in other words, to reduce the thickness of the wound portion. The overlap width of the double wound portion can be easily adjusted without changing. Moreover, even when the can body material is thin, the roundness of the can body is corrected by the flange portion of the can lid, so that uniform winding can be obtained.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; In FIG. 1, reference numeral 1 denotes a can body corresponding to the metal container of the present invention. The can body 1 has a cylindrical can body 2 and a base fixed to an upper open end 3 of the can body 2. It has a lid 4 and a bottom lid 6 fixed to the lower opening end 5 of the can body 2. That is, the can body 1 is a so-called three-piece can and has a capacity of 190 ml to 500 ml and a body diameter of 202 to 30 as an example.
It is intended for one-diameter cans.

The can 1 can be filled with carbonated beverages and non-carbonated beverages (coffee, tea, fruit juice, etc.), that is, a container internal pressure of 275 kPa to carbonated beverages.
It has a structure that can withstand 755 kPa and a structure that can withstand 13.3 kPa to 53.3 kPa in the case of non-carbonated beverages.

More specifically, the can body 2 has a thickness of 0.15 m.
A metal thin plate of about m to 0.23 mm is rolled into a cylindrical shape, and the overlapped edges are welded together and integrally joined. As a metal plate used as a material for the can body 2,
For example, tin-treated steel sheet, tin-plated steel sheet, chrome-plated steel sheet such as tin-free steel (hereinafter referred to as TFS),
Nickel-plated steel sheets and various other alloy-plated steel sheets can be mentioned. An inner surface coating (not shown) made of a synthetic resin is formed on the inner surface of the can body 2. This inner surface coating is formed from a thermoplastic protective paint or a resin film.

The resin film is, for example, a thermoplastic resin film such as a polyester film, a polypropylene film, or a nylon film and has a thickness of 5 μm.
５０50 μm, more preferably 10 μm-30 μm. This is based on the assumption that corrosion resistance is deteriorated due to film damage in the can-making process. In other words, if the content is less than 5 μm, it is not enough to ensure sufficient preservation of the contents. This is because the effect of the above becomes flat and the cost becomes disadvantageous.

The outer diameter of the can body 2 is set substantially constant over its entire length. That is, the can body 2 has a straight shape in which the upper open end 3 and the lower open end 5 have substantially the same outer diameter. The upper opening end 3 and / or the lower opening end 5 may be subjected to neck-in processing. In this case, the inclination angle of the neck-in portion formed at the upper opening end 3, specifically, the center axis of the can body 2 It is preferable to set the angle with respect to a line perpendicular to the above to be the same as the inclination angle of the skirt wall 8 of the cap 4 described later.

On the other hand, the cap 4 is provided integrally with the skirt wall 8 projecting toward the outside of the can body 2 and the upper edge of the skirt wall 8 in a posture along the center axis of the can body 2. Mouth and neck 7 to be formed. The cap 4 is made of, for example, a 3004 series, 50 having a thickness of 0.20 mm to 0.35 mm,
It consists of a 52 series aluminum alloy plate or a surface-treated steel plate laminated on both sides, and in any case,
The inner surface of the can 1 is coated with the same type of inner coating as the can body 2.

FIG. 2 shows the cap 4 which is wound around the can body 2, and the skirt wall 8 has a cylindrical shape tapered so as to have a smaller diameter toward the upper side in FIG. 2. Has formed. The inclination angle of the skirt wall 8, that is, the can body 2
Angle with respect to a line perpendicular to the central axis of
°, more preferably in the range of 25 ° to 45 °. If the angle is less than 20 °, the inclination is too gentle and buckling is likely to occur due to the compressive load applied from the axial direction. On the other hand, if the angle exceeds 50 °, the skirt wall 8 becomes long, and the material cost is accordingly increased. Is bulky. The skirt wall 8 may be slightly curved outward as long as it is within the range of the inclination angle.

A chuck wall 9 is formed integrally with the lower edge of the skirt wall 8. This chuck wall 9 extends downward in FIG. 2 substantially parallel to the central axis of the skirt wall 8. Further, an annular flat plate portion 10 is formed integrally with a lower edge portion of the chuck wall 9. This annular flat plate portion 10
Protrudes toward the outer peripheral side of the can body 2 in a posture substantially orthogonal to the chuck wall 9, and has a length that is suitable for accommodating a double-sealed portion formed in a subsequent stage. . The boundary between the annular flat plate portion 10 and the chuck wall 9 is the first
The curved portion 11 is provided. Note that the annular flat plate portion 10 may be formed in advance in a state corresponding to the inclination angle of the skirt wall 8, but if it is formed on a surface orthogonal to the center axis of the skirt wall 8 as described above, the mouth and neck portion This brings about an advantage of excellent stability when the cap 4 is conveyed in a posture in which the 7 is directed upward.

A flange portion 12 is formed integrally with the outer peripheral edge of the annular flat plate portion 10. This flange portion 12
Extends upwardly in FIG. 3 substantially parallel to the central axis of the skirt wall 8. That is, the flange portion 12 is a surface that faces substantially parallel to the chuck wall 9, and its length (height from the annular flat plate portion 10) is about 2 to 2 of the length of the chuck wall 9.
It is set to 2.4 times. The boundary between the flange portion 12 and the annular flat plate portion 10 is a second curved portion 13. A sealing compound 50 made of, for example, synthetic resin and rubber is applied to outer surfaces of the annular flat plate portion 10 including the second curved portion 13 and the flange portion 12.
Sealing compound 5 corresponding to the sealant of the present invention
Numeral 0 is provided on the upper surface in FIG. 3 of the annular flat plate portion 10 and on the surface of the flange portion 12 facing the chuck wall 9.

On the other hand, on the upper edge of the skirt wall 8,
A substantially cylindrical mouth-and-neck portion 7 serving as a spout in the can body 1 is integrally formed. The central axis of the mouth and neck 7 is aligned with the central axis of the skirt wall 8. A large-diameter cylindrical portion 14 whose side wall surface is substantially parallel to the central axis of the can body 2 is integrally formed at a portion of the mouth and neck 7 connected to the skirt wall 8. Further, a small-diameter cylindrical portion 15 having a diameter slightly smaller than that of the large-diameter cylindrical portion 14 is formed integrally with an upper edge portion of the large-diameter cylindrical portion 14. At the upper edge of the small-diameter cylindrical portion 15, a substantially cylindrical annular locking flange 16 whose minimum outer diameter is set larger than the small-diameter cylindrical portion 15 is integrally formed.

The annular locking flange 16 has an irregular cylindrical shape tapered so as to have a slightly smaller diameter upward in FIG. That is, a step is formed at the boundary between the annular locking flange 16 and the small-diameter cylindrical portion 15.
The step and the small-diameter cylindrical portion 15 are formed by pressing a roller of a cap mounting device into the small-diameter cylindrical portion 15 when the cap is mounted on the mouth-neck portion 7 and pressing the cap against the above-mentioned step while deforming the lower end wall of the cap. The cap is locked to the mouth and neck 7 in a pill fur proof state.

Further, a screw forming portion 17 is integrally formed on the upper edge portion of the annular locking flange portion 16, and the screw forming portion 17 has a male screw 18 for screwing with a screw portion of the cap. Are formed. The screw provided on the screw forming portion 17 is not particularly limited, and a screw formed of a convex portion or a concave portion that winds the cylindrical base of the screw forming portion 17, a discontinuous ridge, It may be a screw formed of a concave groove, and the number of threads can be set to an arbitrary number. Further, an arc-shaped connecting portion 19 which is smoothly curved in a direction approaching the central axis of the can body 2 is integrally formed on the upper edge portion of the screw forming portion 17.

The upper edge of the arc-shaped connecting portion 19 is
While being wound in an arc toward the outside, it is in contact with an intermediate portion in the length direction of the arc-shaped connecting portion 19,
This is the curl portion 20. That is, the curl portion 20
Has an annular shape along the opening edge of the mouth and neck part 7 as a whole, and a vertical cross section of a portion wound outward has a substantially circular shape. As described above, the end face of the curled portion 20 (the upper end fractured surface of the mouth and neck portion 7) is a structure that is not exposed to the outer peripheral surface side of the mouth and neck portion 7 even though it is a metal fractured surface that is not covered with the inner surface coating. Therefore, corrosion is unlikely to occur, and safety is ensured when the consumer drinks the content liquid by directly attaching the mouth to the mouth and neck 7.

The base lid 4 having the above structure is fixed to the can body 2 by doubly tightening the lower edge (hem) of the skirt wall 8 around the upper open end 3 of the can body 2. The engaging portion over the entire circumference of the skirt wall 8 and the upper open end 3 is
The double winding portion 60 is provided. More specifically, as shown in FIG. 4, the double wound portion 60 includes, in order from the outer surface side, the uppermost layer 21 formed of the wall surface of the can body 2, the cover hook 22 formed of the flange portion 12, the sealing compound 50, It has a body hook 23 composed of a wall surface of the upper open end 3, a sealing compound 50, and a lowermost layer 24 composed of the annular flat plate portion 10. The lowermost layer 24 and cover hook 2
The folded portion with 2 is a bent portion 25.

That is, the annular flat plate portion 10 is bent downward so as to have substantially the same inclination direction as the skirt wall 8 to form the lowermost layer 24. The flange portion 12 is bent inward so as to cover the upper surface of the annular flat plate portion 10 to form a cover hook 22. In addition, the can body 2 forms the uppermost layer 21 along the upper surface of the flange portion 12,
The upper open end 3 is bent downward so as to be sandwiched between the flange portion 12 and the annular flat plate portion 10 to form a body hook 23. Therefore, the sealing compound 50 is not exposed outside the can 1. Note that the overlapping range of the cover hook 22 and the body hook 23 is overlapped.

The outer peripheral edge of the double-sealed portion 60, that is, the outermost portion in the radial direction is flush with the outer peripheral surface of the upper open end 3, that is, the double-sealed portion 60 Is set substantially the same as the outer diameter of the can body 2.

On the other hand, the bottom cover 6 is a known can cover made of a thin metal plate having a circular shape, and its outer peripheral edge is double-wound and fixed to the lower opening end 5 of the can body 2. The connecting portion between the bottom cover 6 and the can body 2 is formed as a lower fastening portion 26. On the inner peripheral side of the lower tightening portion 26 of the bottom cover 6, the inside of the can body 2 (upper side in FIG. 1)
An annular groove (not shown) depressed in a U-shaped cross section is formed.

Further, on the inner peripheral side of the annular groove, an annular convex portion (not shown) projecting toward the outside of the can body 2 is formed. Further, the inner peripheral side of the annular projection forms a flat surface. The material of the bottom cover 6 is, for example, 0.17
A TFS having a thickness of 0.3 mm to 0.32 mm is employed, and the inner surface of the can body 1 is coated with the same type of inner coating as the can body 2.

Therefore, according to the can 1 having the structure shown in FIG.
Not only is the uppermost layer 21 of the double wrapped portion 60 flush with the skirt wall 8, but also the double wrapped portion 60 itself is above and outside from the corner which is the boundary between the can body 2 and the skirt wall 8. Because it does not protrude and its corners appear as smooth curved surfaces, it is possible to obtain the same good appearance as a glass container or a plastic container even though it is a metal container, that is, an appearance with a reseal function It becomes a good can.

Further, according to the can body 1 having the structure shown in FIG. 1, since the double tightening portion 60 does not protrude outside the outer peripheral surface of the can body 2, for example, a large number of can bodies 1 are arranged in parallel with each other. Even if it is conveyed, the double wound portion 60 does not abut against the can body 2 of the other can body 1, so that the coating or printing surface applied to the outer surface of the can body 2 is damaged. Has the advantage of being prevented beforehand.

Further, according to the can body 1 having the structure shown in FIG. 1, the folded portion between the uppermost layer and the body hook 23 in the double tightening portion 60 is located at the upper open end 3 in the posture in which the can body 1 stands. Because it is arranged above and near the center axis of the can body 2, even when a large number of metal containers are conveyed in an upright position on the conveyance belt, the double winding portions 60 may be caught and deformed. There is no risk of loosening, that is, it is possible to prevent the leakage of the content liquid from the double winding portion 60 and, consequently, the trouble such as deterioration.

Further, in the can body 1 having the configuration shown in FIG. 1, the rigid double wound portion 60 is disposed at the lower edge portion as the cap 4 so that the cap 4 can be cornered as the internal pressure increases. In this configuration, the annular pressure-resistant reinforcing groove conventionally provided in the can body 1 of this type becomes unnecessary, and the amount of material used for the cap 4 can be reduced accordingly. The weight of the can body 1 can be reduced.

Next, a specific example according to the third aspect of the present invention will be described with reference to FIG. The example shown here is for can body 2
This is an example in which a bead portion is provided. The same members as those in the specific examples shown in FIGS. 1 and 4 are denoted by the same reference numerals, and detailed description thereof will be omitted. A cap 4 is fixed to the upper open end 3 of the can body 2 by winding a lower end (hem) of the skirt wall 8. An annular bead 27 protruding toward the center axis of the can body 2 is formed over the entire circumference of the can body 2 below the double wound portion 60.

More specifically, the annular bead 27 is provided with a double tightening portion 60 when a vertical load is applied to the cap 4.
Is a stopper for suppressing an excessive displacement of the cover hook (the cover hook 22 is separated from the uppermost layer 21).
It is formed along the lower side of the outer peripheral edge of the double wound portion 60. As an example, the longitudinal cross-sectional shape of the annular bead 27 (cross-sectional shape along the central axis of the can body 2) is such that the length of the upper inclined surface 28 is shorter than the lower inclined surface 29, as shown in FIG. The connection point (apex) between the inclined surfaces has a gently curved shape. In addition, a part of the upper inclined surface 28 is in contact with the bent portion 25 of the double wound portion 60.

The amount of protrusion of the annular bead 27 is determined by measuring the amount of the double beaded portion 60 measured in parallel with the central axis of the can body 2.
Is set to about 乃至 to ／ of the width W of the light emitting element. The annular bead 27 has only to have a structure capable of supporting the double wound portion 60 from below. Therefore, the annular bead 27 does not necessarily have to be formed integrally over the entire circumference. May have a structure with an appropriate interval.

Therefore, according to the can 1 having the structure shown in FIG.
For example, when an excessive load is applied to the cap 4 when the sealing cap is plugged into the mouth and neck 7, the cap 4 is bent and the bent portion 25 of the double wound portion 60 is bent.
Abuts on the inner surface of the upper inclined surface 28 of the annular bead 27. Thereby, further displacement of the double wound portion 60 is restricted, and the deformation of the double wound portion 60 itself is suppressed accordingly. That is, the separation between the uppermost layer 21 and the cover hook 22, the separation between the cover hook 22 and the body hook 23, and the separation between the body hook 23 and the lowermost layer 24 are prevented beforehand. Leakage of contents can be reliably prevented.

Hereinafter, a method of manufacturing the can 1 having the structure shown in FIG. 1 will be described with reference to FIGS. First, the step of forming the cap 4 will be described. A thin metal plate of, for example, an aluminum alloy covered with a synthetic resin film is punched into a cup shape having a flange, and a cup shape having a larger diameter than the mouth and neck portion 7 and the skirt wall 8 as shown in FIG. Body 30
a is formed by drawing. Next, the cup-shaped body 30a is subjected to redrawing to form a flanged cup having a horizontal flange portion on the outer peripheral edge.

Further, by gradually drawing the cup with the flange, as shown in FIG. 6 (B), the unfinished mouth and neck portion 7 and the skirt wall 8 whose upper end small diameter portion is closed by the end wall are formed. A lid member 30b including the chuck wall 9 and the annular flat plate portion 10 (including a portion that eventually becomes the flange portion 12) is formed. Further, in order to form the lid member 30b into the final shape of the cap 4, the end wall is first punched to open the small-diameter portion at the upper end of the neck portion 7. 6C, the upper opening edge of the mouth and neck portion 7 is slightly curled outward, and the outer peripheral edge of the flange portion is turned upward as shown in FIG. 6 (C). Let it bend.

Next, in a state where a mold having an arc-shaped portion at the upper peripheral edge is inserted into the inside of the mouth and neck portion 7, a curl forming punch (not shown) is pushed down from above, and as shown in FIG. An outer winding curl portion 20 is formed at the upper end opening edge of the mouth and neck portion 7, and a wall surface of a lower portion thereof is formed into a curved surface bulging outward to form an arc-shaped connecting portion 19. Subsequently, as shown in FIG. 6E, a male screw 18 is formed on the screw forming portion 17 below the arc-shaped connecting portion 19. At this time, the method for forming the thread and the thread valley of the thread forming portion 17 is a method of inserting a female mold into the inside of the mouth and neck portion 7 and pressing a roll from the outside, and a method of forming the thread from the inside of the mouth and neck portion 7. Both methods of pressing and forming a roll can be adopted.

After the threaded portion 17 is formed as described above, as shown in FIG. 6F, the lower side of the threaded portion 17 is formed into the original cylindrical shape as the annular locking flange 16 by a predetermined width. In the state where it is left, the lower end of the mouth-neck portion 7 is formed into the small-diameter cylindrical portion 15 by pressing the roll from the outside below the annular locking flange portion 16. Further, a sealing compound 50 made of synthetic resin and rubber is applied to the outer surfaces of the flange 12 and the annular flat plate portion 10, and is dried and fixed. By the above procedure, the cap 4 having the configuration shown in FIG. 2 is completed.

Next, the cap 4 is fixed to the can body 2 by winding it around. In this specific example, the winding step is performed in two steps. FIG. 7 shows a winding device 70 for performing the first winding process. Since the basic configuration of the device for the second winding step is common to the illustrated winding device 70, detailed description of the device will be omitted, and only different points will be described below.

The winding device 70 includes an upper die 31 movably held in the vertical direction in FIG. 7 and an annular pad 32 movably arranged on the inner peripheral side of the upper die 31. I have.
Further, the winding device includes an annular lower die 33 disposed on the inner peripheral side of the upper die 31 and below the pad 32, and a chuck disposed on the inner peripheral side of the lower die 33 and below the pad 32. 34,
And a pedestal (not shown) arranged below these.

More specifically, the upper die 31 is a member that presses the upper open end 3 from above while holding it from the outer peripheral side of the can body 2 to curl the inner peripheral side portion of the lower end surface. It has a short structure for the part. That is, the lower end surface has a step, and the surface forming the above-described step is the holding surface 35 that comes into contact with the side surface of the can body 2. This holding surface 35 forms a surface parallel to the central axis of the can body 2. On the other hand, the above-mentioned inner peripheral side portion of the upper die 31 serves as pressing surfaces 36 and 37 that come into contact with the upper opening end 3.

The upper die 31 has a different structure depending on the first and second winding steps, and the pressing surface 36 of the upper die 31 used in the first winding step has an annular shape as a whole. It has an arc-shaped cross section. On the other hand, the pressing surface 37 of the upper die 31 used in the second winding step is a flat inclined surface, and the inclination angle is set to be the same as the inclination angle of the skirt wall 8. That is, the angle with respect to a line orthogonal to the center axis of the can body 2 is 30 °.

The pad 32 is a member that presses the boundary between the double wound portion 60 and the skirt wall 8 from the outside.
The lower end surface is a pressing surface 38 that is in close contact with the skirt wall 8. The pressing surface 38 has a flat cross section,
The inclination angle with respect to a line perpendicular to the central axis of the can body 2 is set to 30 °, which is equal to that of the skirt wall 8. Further, the pad 32 has a different structure between the first winding step and the second winding step, and the pad 32 used in the first winding step is higher than the pad 32 used in the second winding step. The space between the mold 31 and the pressing surface 36 is set narrow. In other words, the sliding surface of the pad 32 with the upper die 31 is located on the outer peripheral side.

The lower die 33 is a member for supporting the annular flat plate portion 10 and the can body 2 from inside. The outer peripheral surface of the lower die 33 is a holding surface 39 that is in close contact with the inner peripheral surface of the can body 2, while the upper end surface is the supporting surfaces 40 and 41 that are in close contact with the inner surface of the annular flat plate portion 10. ing. Lower mold 3
3 has a different structure between the first winding step and the second winding step, and the support surface 40 of the lower die 33 used in the first winding step is perpendicular to the center axis of the can body 2. While the supporting surface 41 of the lower mold 33 used in the second winding step is the skirt wall 8 and the pad 32
And a flat surface parallel to the pressing surface 38. That is, the inclination angle of the support surface 41 with respect to a line orthogonal to the central axis of the can body 2 is 30 °.

The chuck 34 is a member fitted on the inner peripheral side of the chuck wall 9 for centering the base 4, and includes a first support surface 42 in surface contact with the inner surface of the skirt wall 8, and a chuck wall. 9, the second support surface 4 in surface contact with the inner surface
3 is provided. The first support surface 42 forms a plane parallel to the skirt wall 8 and the pad 32, whereas the second support surface 43 forms a plane parallel to the central axis of the can body 2.

In the above-described winding device 70, the cap 4 is fitted to the inner periphery of the upper opening end 3 of the can body 2, the cap 4 is put on the chuck 34, and the can body 2 is Processing is performed in a state of covering the outer peripheral surface. The cap 4 is set in a state of being pressed inward with respect to the upper opening end 3 of the can body 2. As an example, the amount of protrusion of the upper opening end 3 with respect to the flange portion 12 of the cap 4 will be described later. The overlap amount is set to a value obtained by adding 0.5 mm to 2.5 mm. That is, if the thickness is less than 0.5 mm, the sealing clearance of the sealing compound becomes small, and the compound tends to protrude. If it exceeds 2.5 mm, the clearance becomes large and the sealing performance deteriorates. Hereinafter, the first winding step by the winding apparatus 70 will be described in detail.

This first winding step is a step of curling the flange portion 12 and the upper open end 3 inward so as not to be in close contact with each other. More specifically, first, as shown in FIG. 7, the pad 32 and the upper mold 31 start descending, and the pad 3
2 reaches the bottom dead center earlier than the upper mold 31 and the chuck 34
Thus, the upper die 31 is in contact with the end face of the upper opening end 3 with the skirt wall 8 sandwiched therebetween.

As shown in FIG. 8, the upper die 31 further descends from the state shown in FIG. 7, and the pressing surface 36 of the upper die 31 comes into contact with the end face of the upper opening end 3, and from that state, the upper die 31 is further lowered. When it descends, as shown in FIG. 9, the upper opening end 3 starts curling toward the chuck wall 9 along the pressing surface 36, and the base of the curled portion comes into contact with the end surface of the flange portion 12. Subsequently, when the upper die 31 descends to its bottom dead center, as shown in FIG.
1 and curl so that the end face of the flange portion 12 faces the chuck wall 9 while entering the inside of the curled portion. As a result, the temporary winding part 80 is completed, and the first winding step is completed.

The unit of the can body 2 and the cap 4 which has been processed is then sent to the second winding step. In the second winding step, the temporary winding section 80 is pressed to be completely fixed to the can body 2. Specifically, as shown in FIG. 11, the pad 32 and the chuck 34 hold the skirt wall 8 in a sandwiched state from inside and outside. A gap is formed between the annular flat plate portion 10 and the support surface 41 of the lower mold 33.

When the upper die 31 further descends from this state,
As shown in FIG. 12, the pressing surface 37 is
In contact with the upper part of the outer peripheral side portion of When the upper die 31 further descends to its bottom dead center, as shown in FIG. 13, the annular flat plate portion 10 is bent downward and the temporary tightening portion 80 is crushed by the upper die 31. That is, the pressing surface 37 of the upper die 31 and the supporting surface 41 of the lower die 33
And the temporary tightening portion 80 is
1 and is crushed in a flat shape to complete the double wound portion 60 having the configuration shown in FIG.

The double-sided tightening portion 60 is configured such that the pressing surface 37 of the upper die 31 and the support surface 41 of the lower die 33 are both
Is set to the same inclination angle as that of the annular flat plate portion 10.
And the flange portion 12, the upper opening end 3, and a part of the can body 2,
Each of them is formed in the same inclined direction as the skirt wall 8 and is formed in a state of being laminated on each other. Although a load acts on the temporary tightening portion 80, since a portion serving as a base point of deformation is sandwiched between the pad 32 and the chuck 34, generation of wrinkles and cracks particularly on the skirt wall 8 is prevented. Is done.

Next, the bottom cover 6 is double-wound and fixed to the lower opening end 5 of the can body 2. As the means, a conventionally known seamer and means can be adopted, and a detailed description thereof will be omitted. By the above procedure, the can 1 having the configuration shown in FIG. 1 is completed.

As described above, according to the above manufacturing method, the flange portion 12 and the upper opening end 3 projecting vertically upward with respect to the line orthogonal to the central axis of the can body 2 Since the winding is performed by curling in a round manner, the double-sealed portion 60 arranged on the substantial skirt of the skirt wall 8 can be formed reliably and efficiently.

According to the above-described manufacturing method, the end face of the upper open end 3 is added to the end face of the flange portion 12 by adding 0.5 mm to 2.5 mm to the amount of overlap, and the end face of the upper end 3 is made to protrude. When sealing is performed, the sealing compound 50 is applied to the outer surface side (the chuck wall 9 side) of the flange portion 12 even when the sealing portion 50 covers the flange portion 12. As compared with the case where the sealing compound 50 is applied, the damage of the sealing compound 50 due to the tip of the flange portion 12 can be prevented, and therefore, the double wound portion 60 having excellent sealing performance can be reliably formed.

Further, according to the above-described manufacturing method, it is possible to change the amount of overlap in the double tightening portion 60 only by changing the amount of protrusion of the end surface of the upper opening end 3 with respect to the end surface of the flange portion 12. In other words, it is possible to easily adjust the amount of overlap without increasing or decreasing the width of the entire double wound portion 60. That is, the highly airtight can 1 can be reliably and easily made.

Next, in order to confirm the effect of the can 1 having the structure shown in FIG. 1, an example having predetermined characteristics was prepared, and the results of various experiments are shown.

(Example) The can body 1 used for the experiment is a reseal can having the structure shown in FIGS. Specifically, the metal thin plate used for the cap 4 has a thickness of 0.315 mm.
A laminate obtained by laminating a polyester film on both sides of an aluminum alloy plate (3004-H191) was used. The above metal sheet is punched into a cup-shaped body 30a having a diameter of 106.7 mm (cutting dia.), And the overall height is 36.7 m by the above-described forming step.
m, the outer diameter of the flange 12 is 74.0 mm, the length of the flange 12 is 4.4 mm, and the height of the chuck wall 9 is 1.5.
mm, and the inclination angle of the skirt wall 8 was set to 30 °. The amount of the sealing compound 50 applied to the flange portion 12 and the annular flat plate portion 10 was set to 65 to 75 mg.

The can body 2 was made of a laminate material in which a polyester film was coated on both sides of a tin-plated steel plate having a thickness of 0.22 mm, and the edges were welded by a conventionally known method. The outer diameter is 74.5 mm (nominal diameter 30
Set to 1).

The bottom cover 6 is made of TF having a thickness of 0.19 mm.
A polyester film laminated on the inner surface of S was used. The outer diameter of the curl portion 20 is 79.2 m.
m (nominal diameter 209), counter sink depth 4.0m
m, the coating amount of the sealing compound 50 is 53 to 63
mg. Further, as a cap for closing the cap 4, a screw cap made of an aluminum alloy having a conventionally known structure is employed.

(Comparative Example) The inclination angle of the skirt wall 8 and the inclination angle of the double winding portion 60 were set to 19 °, and the other values were set to the same as those in the above embodiment.

The can 1 of the above embodiment and the can 1 of the comparative example
Is placed vertically with the cap 4 on the top and the mouth and neck 7
Was placed on a load tester with a cap attached, and a load was applied vertically downward from above the cap to test the buckling strength.

In the above example, it was confirmed that the outer peripheral edge of the double wound portion 60 did not deform even with a vertical load of 1640 N. On the other hand, in the comparative example, buckling occurred on the skirt wall 8 due to the vertical load of 940N.

This is because the crossing angle between the vertical load and the skirt wall 8 in the embodiment is 120 °, which is an angle at which the skirt wall 8 can escape the vertical load, whereas the comparative example It is presumed that the intersection angle between the vertical load and the skirt wall 8 at 109 ° is 109 °, and that the vertical load applied to the cap 4 tends to concentrate on the skirt wall 8.

[0073]

As described above, according to the first aspect of the present invention, the mouth and neck for engaging the sealing cap and the substantially frusto-conical shape connected to one end of the mouth and neck are provided. A skirt wall, a chuck wall extending from a skirt portion of the skirt wall to a side opposite to the mouth-neck portion, an annular flat plate portion extending radially outward from one end of the chuck wall, and a mouth-neck portion from an outer peripheral edge of the annular flat plate portion And a sealant is applied to a surface of the flange portion facing the chuck wall and an upper surface of the annular flat plate portion. Since it protrudes in the same direction as the neck and the annular flat plate is concave with respect to the skirt wall, it is easy to apply the sealant, and the inside of the flange and opening end in the radial direction Towards the seal without damage to the sealant It is possible to easily perform,
In addition, it can be tightened without exposing the sealant.

According to the second aspect of the present invention, there is provided a mouth-and-neck portion in which a cap is engaged with a sealing cap, a substantially frustoconical skirt wall connected to one end of the mouth-and-neck portion,
A chuck wall extending from the bottom of the skirt wall to the side opposite to the mouth and neck, an annular flat plate extending radially outward from one end of the chuck wall, and a flange extending from the outer peripheral edge of the annular flat plate to the mouth and neck side And a sealant applied over the surface of the flange portion facing the chuck wall and the outer surface of the annular flat plate portion, and a double tightening portion formed by winding the flange portion and the opening end portion is annular. It is folded over on the outer surface of the flat plate portion, and the double winding portion is formed substantially in the same inclination direction as the skirt wall toward the inner peripheral side of the can body. In this case, the folded portion of the flange portion does not appear in a protruding state as an external appearance, so that a metal container having good external appearance and resealability can be obtained.

According to the second aspect of the present invention, since the double wound portion does not protrude beyond the outer diameter of the can body, for example, a large number of metal containers rub against each other. In addition, the double-wound portion does not come into contact with the can body of another metal container, so that it is possible to prevent the paint or printed surface applied to the outer surface of the can body from being damaged. Further, according to the invention described in claim 2, since the folded portion of the open end of the double-wound portion is formed along the skirt wall, for example, a plurality of metal containers are set upright on the conveyor belt. When transporting, there is no possibility that the double wound portions are caught by each other and deformed, so that troubles such as leakage or alteration of contents due to loosening of the double wound portions are prevented beforehand.

Further, according to the second aspect of the present invention, the cornering of the cap due to an increase in the internal pressure is suppressed by the double tightening portion provided on the skirt side of the skirt wall. In addition, an annular pressure-resistant reinforcing groove is not required, so that the manufacturing cost can be reduced and the weight can be reduced due to the reduction in the amount of material used for the cap. Further, according to the invention described in claim 2, since the metal container is not provided with the pressure-resistant reinforcing groove in which stress concentrates when an internal pressure is applied to the metal container, loosening of the double-tightened portion caused by deformation of the skirt wall or Damage is prevented beforehand, so that a high airtightness can be obtained.

According to the third aspect of the present invention, the bead portion protruding toward the central axis of the can body is formed on the can body so as to follow a portion closest to the outer peripheral edge of the double wound portion. And the structure is designed to support the double tightened part from below, so even if an excessive load is applied to the cap when the sealing cap is plugged, The displacement is regulated, and as a result, the double-wound portion can be maintained in an expected state.

According to the fourth aspect of the present invention, a mouth-neck portion for engaging the sealing cap, a substantially frustoconical skirt wall connected to one end of the mouth-neck portion, A chuck wall extending from the hem to the opposite side to the mouth-neck portion, an annular flat plate portion extending radially outward from one end of the chuck wall, and a flange portion extending from the outer peripheral edge of the annular flat plate portion to the mouth-neck portion, The end of the flange provided with the surface facing the chuck wall in the flange and the sealant applied over the outer surface of the annular flat plate is shifted inward in the axial direction from the end of the open end to the end of the flange. In the can body in a state in which the open end is fitted to the inner periphery of the open end in a state where the tip of the open end protrudes toward the mouth and neck side, and the open end is put on the flange. (Radial inside and inside the container) A temporary tightening portion is formed, and then the temporary tightening portion is pressed by a male mold and a female mold having a molding surface substantially parallel to the skirt wall, and is substantially in the same inclined direction as the skirt wall and annular. This is a method of forming a double wound portion folded on the outer surface of the flat plate portion, and by changing the amount of shift of the tip of the flange portion with respect to the tip of the open end portion, the overlap amount of the double wound portion is reduced. The metal container can be easily changed, that is, the overlap of the double-sealed portion can be adjusted without changing the tightened thickness, so that a metal container with high product accuracy can be reliably and easily manufactured.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a specific example according to the first and second aspects of the present invention.

FIG. 2 is a schematic view showing a cross section of a cap.

FIG. 3 is a schematic view showing an annular flat plate portion and a flange portion.

FIG. 4 is a schematic view showing a cross section of the double wound portion.

FIG. 5 is a schematic view showing a specific example according to the invention of claim 3;

FIG. 6 is a schematic view showing a step of forming a cap.

FIG. 7 is a schematic view showing a state where a skirt wall is held by a pad and a chuck in a first winding tightening step.

FIG. 8 is a schematic diagram illustrating a state in which the pressing surface of the upper die abuts on the upper opening end in the process.

FIG. 9 is a schematic diagram showing a state in which the upper open end has started curling in the process.

FIG. 10 is a schematic view showing a state in which a temporary tightening portion is formed in the process.

FIG. 11 is a schematic view showing a state in which a skirt wall is held by a pad and a chuck in a second winding step.

FIG. 12 is a schematic view showing a state in which the pressing surface of the upper die abuts the temporary winding portion in the process.

FIG. 13 is a schematic view showing a state in which a double tightening portion is completed in the process.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... can body, 2 ... can body, 3 ... upper open end, 4 ... base cover, 6 ... bottom cover, 7 ... neck and neck, 8 ... skirt wall,
9: chuck wall, 10: annular flat plate portion, 12: flange portion, 21: top layer, 22: cover hook, 23
... body hook, 25 ... bent part, 27 ... annular bead, 31 ... upper mold, 32 ... pad, 33 ... lower mold,
34: chuck, 50: sealing compound,
60: double winding part; 70: winding device; 80: temporary winding part.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E033 AA01 BA07 BB07 DA03 DB01 DD01 3E062 AA09 AB02 AC03 KA04

Claims (4)

[Claims] 1. A metal container cap which is fixedly wound around an open end of a cylindrical metal container, wherein a mouth-and-neck portion for engaging a sealing cap and one end of the mouth-and-neck portion are provided. A skirt wall having a substantially frusto-conical shape, a chuck wall extending from a skirt portion of the skirt wall to a side along the central axis of the skirt wall and opposite to the mouth-neck portion, and one end of the chuck wall. An annular flat plate portion extending radially outward from the portion, and a flange portion extending from the outer peripheral edge of the annular flat plate portion to the mouth and neck portion in a position along the central axis of the skirt wall, and A cap for a metal container, wherein a sealant is applied to a surface facing the chuck wall and an upper surface of the annular flat plate portion. 2. A metal container comprising a cylindrical metal can body and a cap fixedly wound around one open end of the can body, wherein the cap is used for sealing. A mouth and neck for engaging the cap,
A substantially frusto-conical skirt wall connected to one end of the mouth and neck, and a chuck wall extending from the skirt of the skirt wall to a side along the central axis of the skirt wall and opposite to the mouth and neck. An annular flat plate portion extending radially outward from one end of the chuck wall, and a flange portion extending from the outer peripheral edge of the annular flat plate portion toward the mouth and neck portion in a position along the central axis of the skirt wall, A sealant applied to the flange portion facing the chuck wall and an outer surface of the annular flat plate portion; and a double tightening portion formed by winding the flange portion and the opening end portion. In substantially the same inclination direction as the skirt wall,
And a metal container which is folded on an outer surface of the annular flat plate portion. 3. A bead portion protruding from the can body toward the central axis of the can body is formed along a portion closest to an outer peripheral edge of the double-sealed portion. The metal container according to claim 2, wherein 4. A method for manufacturing a metal container comprising: a cylindrical metal can body; and a cap which is fixedly wound around one open end of the can body, wherein the sealing cap is provided. A mouth-and-neck portion to be engaged, a substantially frustoconical skirt wall connected to one end of the mouth-and-neck portion, and the mouth-and-neck portion in a posture along a center axis of the skirt wall from a skirt portion of the skirt wall. A chuck wall extending in a direction opposite to the chuck wall, an annular flat plate portion extending radially outward from one end of the chuck wall, and the mouth and neck in a posture along the center axis of the skirt wall from the outer peripheral edge of the annular flat plate portion. A base lid having a flange portion extending toward the opening portion, and a sealant applied over a surface of the flange portion facing the chuck wall and an upper surface of the annular flat plate portion. More axial than end tip The opening end is fitted to the inner periphery of the opening end, and the opening end is curled toward the inside of the can body so that the opening end covers the flange. Then, the temporary winding portion is pressed by a male mold and a female mold having a molding surface having substantially the same inclination direction as the skirt wall, and in the substantially same inclination direction as the skirt wall, A method for producing a metal container, comprising forming a double-wound portion folded on the outer surface of the annular flat plate portion.