JP7357430B2 - Bottle cans and bottle cans with caps - Google Patents

Description

The present invention relates to a bottle can that can prevent neck deformation due to molding load during capping even when the can is made thinner, and a bottle can with a cap.

BACKGROUND ART BACKGROUND OF THE INVENTION BACKGROUND ART BACKGROUND ART Bottle cans such as those shown in Patent Document 1 below are known.
The bottle can is made of an aluminum alloy material or the like and is formed into a cylindrical shape with a bottom. A bottle can includes a can body, which is a peripheral wall of the can, and a can bottom, which is a bottom wall of the can. The opening of the can body is a mouthpiece having a smaller diameter than the other parts (body and shoulder).

6 and 7 are vertical cross-sectional views of the vicinity of the mouthpiece 101 of the conventional bottle can 100 along the can axis O direction. The mouthpiece 101 of the bottle can 100 includes a threaded part 102 and a bulging part 103 that is arranged below and adjacent to the threaded part 102 and bulges outward in the radial direction and extends all around the can axis O. and a cylindrical neck 104 which is disposed below and adjacent to the bulge 103 and has a smaller diameter than the bulge 103.
After the bottle can 100 is filled with contents such as a beverage, a cap 105 in the shape of a capped cylinder is attached to the mouthpiece 101 .

Specifically, as shown in FIG. 6, first, a cap 105 is placed on the mouthpiece 101, and a load (axial load) is applied downward from above the cap 105 using a pressure block (not shown) to seal the bottle can 100. state. In this sealed state, a screw roll (not shown) is pressed radially inward against the peripheral wall of the cap 105 and rolled in the circumferential direction around the can axis O. , a female thread shape that follows the male thread shape of the threaded portion 102 is formed. Further, while applying a radially inward load (lateral load) with the hem roll 50 to the lower end of the peripheral wall of the cap 105, the hem roll 50 is rolled all the way around the can axis O, The lower end of the peripheral wall of the cap 105 is hemmed. Thereby, as shown in FIG. 7, the lower end of the peripheral wall of the cap 105 fits closely into the bulge 103.

JP2004-276990A

Conventional bottle cans had the following problems.
For this type of bottle can, there is a demand for thinner walls for the purpose of reducing raw material costs. However, if the can is simply made thinner, there is a risk that the neck will deform into an elliptical shape or the like in a cross-sectional view perpendicular to the can axis due to forming loads (axial load and lateral load) during capping.

In addition, in FIGS. 6 and 7, the hem roll 50 is strongly pressed against the neck portion 104 of the base portion 101 located below the lower end of the peripheral wall of the cap 105, which causes the neck portion 104 to become the starting point of the deformation. Sometimes it collapsed.
Specifically, the hem (lower end of the peripheral wall) of the cap 105 reaches the lower end of the bulge 103, and in order to securely wrap the hem of the cap 105, the tip (outer periphery) of the hem winding roll 50 must be wrapped around the neck 104 during capping. If strong pressure is required and the can is made thinner, there is a risk that the neck portion 104 will not be able to withstand this pressure (lateral load) and may be deformed.

The present invention has been made in view of these circumstances, and provides a bottle can and a bottle with a cap that can prevent neck deformation due to molding load during capping even when the can is made thinner. The purpose is to provide cans.

One aspect of the present invention is a bottomed cylindrical bottle can including a can body and a can bottom, wherein the mouthpiece of the can body is adjacent to a threaded part and below the threaded part, and has a diameter of A bulging portion that bulges outward in the direction and extends over the entire circumference around the can axis, and around which the lower end of the circumferential wall of the crested cylindrical cap attached to the mouthpiece is hemmed; a sloping part that is arranged adjacent to the slanted part and slants radially inward as it goes downward; and a neck part that is arranged below the slanted part and has a diameter smaller than that of the slanted part; The difference between the maximum outer diameter and the minimum outer diameter of the neck is 2.5 to 10.0 mm, and the minimum outer diameter of the neck is 28 to 35.5 mm .
Further, one aspect of the present invention provides a bottle can with a cap, which includes a bottomed cylindrical bottle can including a can body and a can bottom, and a capped cylindrical cap attached to a mouthpiece of the can body. In the bottle can, the cap portion is disposed adjacent to a threaded portion below the threaded portion, bulges outward in the radial direction and extends all around the can axis, and the lower end of the peripheral wall of the cap is a bulging part to be hemmed; a slanted part arranged adjacently below the lower end of the peripheral wall of the cap and sloping radially inward as it goes downward; and a neck portion having a small diameter, wherein the difference between the maximum outer diameter of the bulged portion and the minimum outer diameter of the neck portion is 2.5 to 10.0 mm, and the minimum outer diameter of the neck portion is , 28 to 35.5 mm .

According to the bottle can and the bottle can with a cap of the present invention, the mouthpiece of the can body has an inclined part, and the inclined part is arranged below and adjacent to the bulge, and is fitted into the bulge. The cap is disposed below and adjacent to the lower end of the peripheral wall of the cap, and is formed to be inclined radially inward as it goes downward. In other words, instead of the cylindrical neck parallel to the can axis being placed adjacent to the bulge below the bulge as in the past, in the present invention, the cylindrical neck is placed between the bulge and the neck, gradually moving downward. A tapered sloped portion extending radially inward is provided.
In a longitudinal cross-sectional view of the bottle can, the inclined portion is disposed outside the extension line of the lower end of the bulging portion (the outside of the can, which may also be referred to as the radially outside). Then, the hem roll (the tip thereof) that hems the lower end of the peripheral wall of the cap is brought into contact with this inclined portion. In other words, the hem roll comes into contact with the sloped part rather than the neck part.

Therefore, during capping, when the hem roll rolls the lower end of the peripheral wall of the cap into the bulge, the hem roll comes into contact with the cap peripheral wall as well as the sloped part, which slopes radially inward. The pressing force (lateral load) from the hem roll on the inclined portion can be reduced by the amount of escape.
Specifically, compared to the conventional structure in which the neck is arranged adjacently below the bulge, in the present invention, the inclined part is arranged radially inward than the conventional neck by the amount that the inclined part is provided. can. Since the hem roll is biased radially inward by the spring force, the tip of the hem roll (flange on the outer periphery) is pressed against the sloped part that escapes radially inward. The pressing force that the inclined portion receives from the hem roll can be kept small. Further, since the inclined portion is inclined, the pressing force of the hem roll can be dispersed to the lower part in the can axis direction, etc., other than the radially inner side. Further, it is possible to prevent the hem roll from coming into contact with a portion other than the inclined portion (for example, a neck portion located below the inclined portion). Therefore, due to these synergistic effects, deformation of the neck can be effectively suppressed.

Here, the radially inward pressing force that the neck receives from the hem roll and the corresponding amount of deformation of the neck will be explained. The amount of deformation (the amount of change in radius) ΔR of the neck can be expressed by the following formula from material mechanics.
△R=(R ² /tE)×P
In the above equation, P is the external pressure (the pressure that the neck receives from the hem roll toward the inside in the radial direction), R is the radius of the neck (inner diameter), t is the thickness of the neck (wall thickness), and E is Young's modulus. be. From the above equation, it can be seen that when the external pressure P, the thickness t, and the Young's modulus E are constant, the amount of deformation ΔR of the neck is proportional to the square of the radius R of the neck. In other words, as the radius R of the neck becomes smaller, the amount of deformation ΔR of the neck also becomes smaller in proportion to the square of the radius R (actually, when the radius R changes, the thickness t also changes slightly, but (Since it is a minute amount, it will not be considered here).

In the present invention, since the inclined portion is formed above the neck as described above, the outer diameter of the neck is reduced. In other words, since the neck radius R of the bottle can of the present invention is smaller than that of the conventional bottle can, even if the pressing force received from the hem roll is the same as that of the conventional bottle can, the neck deformation amount △R is reliably reduced and deformation of the neck is prevented.

As described above, according to the bottle cans and bottle cans with caps of the present invention, even if the cans are made thinner, the neck part can be reliably prevented from being deformed by the forming load (axial load or lateral load) during capping. It can be prevented.

Further, in the bottle can, the difference between the maximum outer diameter of the bulge and the minimum outer diameter of the neck is 2.5 to 10.0 mm.

If the difference between the maximum outer diameter (diameter) of the bulge and the minimum outer diameter (diameter) of the neck is 2.5 mm or more, the length of the slope located between the bulge and the neck is This can be secured sufficiently, and it is possible to more reliably prevent the hem roll from hitting the neck. Furthermore, the radius R of the neck is made sufficiently small, so that the amount of deformation ΔR of the neck can be stably kept small.
Moreover, if the above-mentioned difference is 10.0 mm or less, the formability of the inclined portion can be maintained satisfactorily. In other words, when forming the sloped portion by die processing, for example, it is possible to prevent cracks and the like that would occur due to the sloped portion being rapidly expanded in diameter upward from the neck portion.
Incidentally, in order to make the above-mentioned effects even more remarkable, it is more preferable that the above-mentioned difference is 3.0 to 7.0 mm.
Moreover, the bottle diameter of the bottle can may be 38 mm.

Further, in the bottle can, when viewed in a longitudinal section including the can axis , it is preferable that the angle at which the inclined portion inclines with respect to the can axis is 20 to 40°.

If the angle of inclination of the inclined part with respect to the can axis is 20 degrees or more when viewed in a longitudinal section including the can axis of the bottle can, the inclined part is sufficiently inclined (layed down) and the inclined part It is possible to more reliably prevent the hem roll from hitting the hem roll strongly.
In addition, if the angle of inclination of the inclined part with respect to the can axis is 40 degrees or less in the vertical cross-sectional view, the inclined part is tilted too much (overly laid down), and the load capacity of the cap part (especially This can prevent a reduction in the bearing capacity against axial loads.

Further, in the bottle can, when viewed in a longitudinal section including the can axis, the inclined part has a linear shape, and the amount of displacement in the radial direction per unit length of the inclined part along the can axis direction is as follows: The displacement amount may be smaller than the displacement amount of the lower portion of the bulging portion .
Further, in the bottle can, the inclined portion may have a concave curve shape when viewed in a longitudinal section including the can axis.

In a vertical cross-sectional view of the bottle can, the inclined portion may be formed in a straight line or a concave curve as appropriate. When the sloped part is formed in a straight line, it becomes easier to connect the sloped part to the lower end of the bulged part without a step, and when the sloped part is formed in a concave curved shape, moldability is further improved. .

Further, in the bottle can, it is preferable that the bulging portion and the inclined portion are connected so as to touch each other at a connecting portion when viewed in a longitudinal section including the can axis .

In this case, it is easy to mold the cap portion, and it is possible to prevent the cap portion from buckling and deforming starting from the connecting portion between the bulging portion and the inclined portion. Also, the appearance (beauty) of the cap is good.

Further, in the capped bottle can, the distance from the lower end of the peripheral wall of the cap to the lower end of the inclined portion along the can axis direction is preferably 2 to 6 mm.

If the distance in the can axis direction between the lower end of the peripheral wall of the cap and the lower end of the sloped portion is 2 mm or more, it is possible to more reliably prevent the hem roll from hitting the neck. This is because the vertical thickness of the outer peripheral edge (flange) of the hem roll is 2 mm or more.
Further, if the distance is 6 mm or less, it is possible to suppress a reduction in the axial load resistance of the inclined portion due to the inclined portion becoming too long.

Moreover, in the above-mentioned bottle can with a cap, a hem roll trace extending around the can axis may be formed on the inclined portion.

When the hem roll comes into contact with the inclined part during capping, a hem roll trace extending around the can axis is formed on the inclined part. As described above, in the present invention, since the pressing force of the hem roll on the inclined portion can be suppressed to a small level, the hem roll trace can be made less noticeable. In addition, deformation of the neck is also suppressed.

Further, in the capped bottle can , no hem roll traces extending around the can axis are formed on the neck portion.

Since the hem roll does not come into contact with the neck during capping, no hem roll traces extending around the can axis are formed on the neck. Since no hem roll marks are formed on the neck, the beauty of the cap can be improved. And deformation of the neck can be more reliably prevented.

According to the bottle can and the bottle can with a cap of the present invention, even if the can is made thinner, deformation of the neck due to the molding load during capping can be prevented.

FIG. 1 is a longitudinal sectional view showing a bottle can and a capped bottle can according to an embodiment of the present invention. FIG. 2 is a longitudinal cross-sectional view of the vicinity of the mouthpiece of a bottle can and a capped bottle can according to an embodiment of the present invention. FIG. 2 is a longitudinal cross-sectional view of the vicinity of the mouthpiece of a bottle can and a capped bottle can according to an embodiment of the present invention. FIG. 2 is an enlarged longitudinal cross-sectional view showing the vicinity of the mouthpiece of the capped bottle can (bottle can) according to the present embodiment before the cap hem is formed. FIG. 2 is an enlarged vertical sectional view showing the vicinity of the mouthpiece of the capped bottle can (bottle can) according to the present embodiment after the cap hem is formed. FIG. 2 is a vertical cross-sectional view of the vicinity of the mouthpiece of a conventional bottle can and a bottle can with a cap. FIG. 2 is a vertical cross-sectional view of the vicinity of the mouthpiece of a conventional bottle can and a bottle can with a cap.

Hereinafter, a bottle can 10 and a capped bottle can 20 according to an embodiment of the present invention will be described with reference to the drawings. Note that the drawings used to explain this embodiment may show important parts enlarged, emphasized, or excerpted in order to make it easier to understand the features of the present invention, and the dimensional ratio of each component etc. is not necessarily the same as the actual one.

The bottle can 10 is made of an alloy containing aluminum as a main component, such as 3004 material or 3104 material. As shown in FIG. 1, the bottle can 10 in this embodiment is a bottle can that has a total length along the can axis O direction (that is, can total height) of about 133 mm and is called a "310B" size by those skilled in the art. listed. However, the present invention is not limited thereto, and the bottle can 10 may be, for example, a bottle can with a total height of about 164 mm, which is called a "410B" size by those skilled in the art.

The bottle can 10 is filled with contents such as a beverage, and a cap 15 is attached to a mouthpiece 5 of a can body 1 to be sealed, thereby forming a capped bottle can 20. That is, the capped bottle can 20 includes a bottle can 10 having a cylindrical shape with a bottom and a cap 15 having a cap 15 attached to the mouthpiece 5 of the bottle can 10 .

The bottle can 10 includes a can body 1, which is a peripheral wall of the can, and a can bottom 2, which is a bottom wall of the can. The central axis of the can body 1, the central axis of the can bottom 2, and the central axis of the cap 15 are arranged coaxially with each other, and in this embodiment, these common axes are referred to as a can axis O.
Further, the direction in which the can axis O extends (the direction along the can axis O) is referred to as the can axis O direction. In the direction of the can axis O, the direction from the can bottom 2 toward the mouthpiece 5 of the can body 1 and the cap 15 is referred to as upward, and the direction from the cap 15 and mouthpiece 5 toward the can bottom 2 is referred to as downward.
Further, the direction perpendicular to the can axis O is referred to as the radial direction. In the radial direction, the direction approaching the can axis O is called the radially inner side, and the direction away from the can axis O is called the radially outer side.
Further, the direction in which the can revolves around the can axis O is called the circumferential direction.

Unless otherwise specified, various shapes of the bottle can 10 used in this embodiment, such as "concave", "convex", "concave", and "protruding", refer to the outer surface of the bottle can 10 (can outer surface. represents various shapes on exposed surfaces).
In addition, in a longitudinal cross-sectional view along the can axis O direction (a vertical cross-sectional view including the can axis O) of the bottle can 10 (bottle can with cap 20) shown in FIGS. 1 to 5, the shape of each part of the bottle can 10 will be explained. Line shapes such as "arc,""curve,""straightline,""tangentialline," and "extension line" used herein represent various line shapes on the outer surface of the bottle can 10 unless otherwise specified.

In FIG. 1, the can bottom 2 includes an annular protrusion (rim) 11 that protrudes downward and extends along the circumferential direction, and a recess that is connected to the radially inner side of the annular protrusion 11 and extends upward. and a dome portion 12.
The can body 1 also includes a body 3 that connects to the can bottom 2, a shoulder 4 that slopes radially inward as it goes upward from the body 3, and a cap that stands above the shoulder 4. Part 5 is provided.

The body portion 3 is connected to the outer peripheral edge of the annular convex portion 11 of the can bottom 2, and extends upward from the outer peripheral edge. The body 3 has a cylindrical shape with a substantially constant outer diameter along the can axis O direction. The body 3 is the largest diameter portion of the can body 1, and the outer diameter of the body 3 is, for example, 65 to 67 mm.
The shoulder portion 4 is connected above the body portion 3 and has a tapered shape whose diameter gradually decreases upward from the body portion 3.

In FIGS. 1 to 5, the base portion 5 is connected above the shoulder portion 4. As shown in FIGS. The mouthpiece 5 is the smallest diameter portion of the can body 1.
The cap part 5 includes a threaded part 6, a bulging part 7 which is disposed adjacent to the lower part of the threaded part 6, bulges outward in the radial direction and extends over the entire circumference in the circumferential direction, and a bulging part 7 below the bulging part 7. It includes an inclined part 21 arranged adjacent to each other, a neck part 8 arranged below the inclined part 21 and having a smaller diameter than the inclined part 21, and a curled part 9 formed at the upper opening edge of the cap part 5. ing. In addition, in the example of this embodiment, in the vertical cross-sectional view of the bottle can shown in FIGS. 4 and 5, a concave curved part 22 is formed between the inclined part 21 and the neck part 8 to connect them and form a concave curved shape. has been done.

The threaded portion 6 is formed with a spiral male thread that extends toward the can axis O as it goes in the circumferential direction.
The bulging portion 7 has an annular shape that bulges outward in the radial direction and extends along the circumferential direction. The bulging portion 7 is also called a turnip. The outer diameter of the bulging portion 7 is equal to or larger than the outer diameter of the threaded portion 6, and is larger than the outer diameter of the threaded portion 6 in the example of this embodiment. The maximum outer diameter (diameter) of the bulging portion 7 is, for example, about 38.0 mm. The maximum outer diameter of the bulging portion 7 corresponds to the bottle diameter. In other words, the bottle can 10 of this embodiment has a diameter of 38 mm.

As shown in FIGS. 3 and 5, the lower end of the peripheral wall of the cap 15 attached to the base portion 5 is wrapped around the bulge portion 7. As shown in FIGS. When the cap 15 is attached to the mouthpiece 5 and the circumferential wall of the cap 15 is fitted to the radially outer side of the bulge 7, the lower end of the bulge 7 and the lower end of the circumferential wall of the cap 15 are in contact with each other. They are arranged at substantially the same position (substantially coincident).

In the longitudinal cross-sectional view of the bottle can shown in FIGS. 4 and 5, the bulging portion 7 is arranged adjacent to the upwardly convex curved portion 16 below the threaded portion 6 and adjacently below the upwardly convex curved portion 16. It has a middle convex curved part 17 , a downwardly convex curved part 18 arranged below and adjacent to the middle convex curved part 17 , and a straight part 19 arranged below and adjacent to the downwardly convex curved part 18 . In a longitudinal cross-sectional view of the bottle can, the upper convex curved portion 16, the middle convex curved portion 17, and the lower convex curved portion 18 all have a curved shape that is convex toward the outside in the radial direction, and have different radii of curvature. There is. In the illustrated example, the radius of curvature of these convex curved portions is increased in the order of downward convex curved portion 18 , upward convex curved portion 16 , and middle convex curved portion 17 .

The upwardly convex curved portion 16 is continuous with the lower end of the threaded portion 6 and is inclined radially outward as it goes downward. The middle convex curved portion 17 is smoothly connected to the lower end of the upper convex curved portion 16, and is inclined radially outward as it goes downward. The amount of displacement (that is, the inclination) in the radial direction per unit length of the middle convex curved portion 17 along the direction of the can axis O is smaller than the displacement amount of the upwardly convex curved portion 16 .

The downwardly convex curved portion 18 smoothly extends in contact with the lower end of the middle convex curved portion 17, and is inclined radially inward as it goes downward. In the longitudinal cross-sectional view of the bottle can shown in FIG. 5, the radius of curvature r2 of the downwardly convex curved portion 18 (on the outer surface of the can) is 1.0 to 1.6 mm. The straight portion 19 smoothly extends in contact with the lower end of the downwardly convex curved portion 18, and is inclined radially inward as it goes downward. In a vertical cross-sectional view of the bottle can, the straight portion 19 has a straight shape.
In this embodiment, as shown in FIG. 5, the lower end of the peripheral wall of the cap 15 is hemmed around the downwardly convex curved portion 18 and the straight portion 19 of the bulging portion 7.

Further, in the longitudinal cross-sectional view of the bottle can shown in FIG. 5, the angle at which the lower part (straight portion 19) of the bulging portion 7 is inclined with respect to the can axis O is 36 to 50°. Note that the above-mentioned angle refers to an acute angle between an acute angle and an obtuse angle formed between the can axis O and the lower part of the bulging portion 7 in a vertical cross-sectional view of the bottle can. That is, in the vertical cross-sectional view of the bottle can 10, the acute angle between the acute angle and the obtuse angle formed between the can axis O and the extension line L of the lower end of the bulging portion 7 is 36 to 50°.

As shown in FIGS. 2 to 5, the inclined portion 21 is inclined radially inward as it goes downward, and in the example of this embodiment, it touches the hem roll 50 together with the lower end of the peripheral wall of the cap 15. be touched. The inclined part 21 is connected to the lower end of (the straight part 19 of) the bulging part 7, and has a tapered shape whose diameter gradually decreases as it goes downward. In a longitudinal cross-sectional view of the bottle can 10, the bulging part 7 (the lower part thereof) and the inclined part 21 are smoothly connected without a step so as to be in contact with each other at the connecting part (so that they have a common tangent line).

In a longitudinal cross-sectional view including the can axis O, the inclined portion 21 is located outside the extension line L of the lower end of the bulging portion 7 (outside the can, radially outside). In this embodiment, the lower end of (the linear part 19 of) the bulging part 7 is defined as the position 7a where the tip of the hem of the peripheral wall of the cap 15 comes into contact, as shown in FIG.

In a longitudinal cross-sectional view of the bottle can 10 along the can axis O direction shown in FIGS. 2 to 5, the inclined portion 21 has a linear shape that extends obliquely in a direction intersecting the can axis O. The amount of displacement (that is, the inclination) in the radial direction per unit length of the inclined portion 21 along the direction of the can axis O is smaller than the amount of displacement of the lower portion (straight portion 19) of the bulging portion 7.

In the vertical cross-sectional view of the bottle can 10 shown in FIGS. 2 and 3, the angle θ at which the inclined portion 21 is inclined with respect to the can axis O is 20 to 40°. In the illustrated example, the angle θ is approximately 30°. In other words, in a longitudinal cross-sectional view of the bottle can, the angle (90°-θ) at which the slope portion 21 slopes with respect to a virtual straight line (not shown) perpendicular to the can axis O is approximately 60°.
Note that the angle θ in this embodiment refers to an acute angle between an acute angle and an obtuse angle formed between the can axis O and the inclined portion 21 in a longitudinal section view of the bottle can 10.
In the longitudinal cross-sectional view of the bottle can shown in FIGS. 3 and 5, the angle θ at which the inclined portion 21 is inclined is smaller than the angle at which the lower part (straight portion 19) of the bulging portion 7 is inclined with respect to the can axis O. has been done.

In the capped bottle can 20 shown in FIGS. 3 and 5, the inclined portion 21 is arranged adjacently below the lower end of the peripheral wall of the cap 15, and extends obliquely downward from the lower end of the peripheral wall of the cap 15. ing. In FIG. 5, the distance A from the lower end of the peripheral wall of the cap 15 to the lower end of the inclined portion 21 along the can axis O direction is 2 to 6 mm. Specifically, the direction of the can axis O from the lowest end of the peripheral wall of the cap 15 including the plate thickness to the lower end of the sloped portion 21 that connects to the concave curved portion 22 (the connection point between the sloped portion 21 and the concave curved portion 22). The distance A is 2 to 6 mm. It is preferable that the distance A is set to be greater than or equal to the thickness of the hem roll 50, which will be described later. That is, the vertical thickness (vertical width of the roll tip) of the outer peripheral edge (flange) of the hem roll 50 is at least 2 mm. Also, regarding the distance in the direction of the can axis O from the lower end of the bulging part 7 (straight part 19) to the lower end of the inclined part 21 (to the upper end of the concave curved part 22), the thickness of the lower end of the peripheral wall of the cap 15 is taken into consideration. It is 2.2 to 6.2 mm.

The concave curved portion 22 is continuous below the inclined portion 21 and has a concave curved shape that is concave toward the inside in the radial direction. The concave curved portion 22 smoothly connects the inclined portion 21 and the neck portion 8. In the longitudinal cross-sectional view of the bottle can shown in FIG. 5, the radius of curvature r1 of the concave curved portion 22 is 0.8 to 1.4 mm.

The neck portion 8 continues below the concave curved portion 22 and is the portion formed between the bulge portion 7 and the shoulder portion 4 to have the smallest diameter. In the example shown in FIGS. 4 and 5, the neck 8 has a cylindrical shape extending parallel to the can axis O. For example, instead of this, the neck portion 8 may have a concave curved shape concave toward the inside in the radial direction.

The minimum outer diameter (diameter) of the neck portion 8 is 28 to 35.5 mm. In the example of this embodiment, the minimum outer diameter of the neck portion 8 is approximately 32 mm. Further, the difference between the maximum outer diameter (diameter) of the bulging portion 7 and the minimum outer diameter (diameter) of the neck portion 8 is 2.5 to 10.0 mm. Preferably, the difference is between 3.0 and 7.0 mm.
The thickness (wall thickness, plate thickness) of the neck portion 8 is, for example, 0.250 to 0.335 mm.

In the example of this embodiment, a concave curved section is continuous below the neck section 8, and the upper end of the shoulder section 4 is connected below the concave curved section. Note that a stepped portion (not shown) may be provided between the neck portion 8 and the shoulder portion 4 for the purpose of increasing the buckling strength of the can.

The curl portion 9 is located at the upper opening edge of the base portion 5. The tip (material end) of the curled portion 9 is folded downward from the outside in the radial direction. The curl portion 9 has an annular shape extending along the circumferential direction. In this embodiment, either the curl portion 9 or the neck portion 8 is the smallest diameter portion of the mouthpiece portion 5. In the illustrated example, the entire outer circumference of the curled portion 9 is subjected to a radially inward throttle process (curl crushing process), so that the outer circumferential surface of the curled portion 9 is parallel to the can axis O. It has a cylindrical shape.

Next, an example of the manufacturing process will be described regarding the method for manufacturing the bottle can 10 and the capped bottle can 20 of this embodiment.
The bottle can 10 undergoes a board punching process, a cupping process (drawing process), a DI process (drawing and ironing process), a trimming process, a printing/painting (outside of the can) process, a painting (inside of the can) process, a necking process, a trimming process, and a screwing process. Cans are made through a molding process, a curling process, a throttle process, etc.

In the plate material punching process, a rolled material (plate material) made of an aluminum alloy material or the like is punched to form a disc-shaped blank.
In the cupping process (drawing process), the blank is drawn using a cupping press (cupping process) to form a cup-shaped body having a bottomed cylindrical shape.

In the DI process (drawing and ironing process), the cup-shaped body is redrawn and ironed using a DI can manufacturing apparatus to form a bottomed cylindrical DI can including a can body and a can bottom. Note that "DI" is an abbreviation for Drawing & Ironing.
Further, in the DI process, the above-mentioned annular convex portion 11 and dome portion 12 are press-molded on the can bottom.

In DI cans that have undergone the DI process, the open end of the can body has an uneven shape, so-called ears are formed, and the height is uneven. For this purpose, the open end of the can body is trimmed using a trimming device to produce a DI can in which the height of the open end is uniform over the entire circumference (trimming step).

Next, after washing the DI can to remove oil and the like, surface treatment is applied and dried, the outer surface of the DI can is printed and painted (printing/painting (can outer surface) process), and the inner surface of the DI can is painted. (Painting (can inner surface) process).
The outer surface of the DI can is printed and coated with an outer finishing varnish. Printing and exterior finishing are applied wet-on-wet, then baked and dried.
Furthermore, after the exterior surface is painted, the interior surface is painted, dried, and baked. The inner surface of a DI can is painted by spraying paint from the opening of the can body toward the bottom of the can using a spray nozzle. By drying the sprayed paint, a coating film is formed on the inner surface of the can, providing corrosion resistance.

This DI can is transferred to a bottle can manufacturing device. In bottle can manufacturing equipment, the shoulder portion 4 and the mouthpiece portion 5 are formed by performing die processing (necking processing) in stages near the opening of the can body using multiple types of die processing tools (necking molds). (necking process).
Specifically, the shoulder portion 4 and the neck portion 8 are formed by stepwise reducing the diameter near the opening of the can body by die processing. The concave curved section 22, the inclined section 21, and the lower part of the bulging section 7 (the straight section 19, the downwardly convex curved section 18, etc.) are formed by gradually expanding the diameter near the opening of the can body by die processing.
Further, if necessary, between the plural types of die processing, a trimming processing tool is used to trim the opening end portions whose heights are uneven (trimming process).

Next, the mouthpiece 5 of the can body 1 is subjected to thread forming using a thread forming tool (thread forming process). Further, the upper end opening of the mouthpiece 5 is curled using a curling tool (curling process), and throttled using a throttle processing tool (curl crushing tool). As a result, the threaded portion 6 and the curled portion 9 are formed on the base portion 5. Note that a plurality of die processes and trimming processes may be performed between the above-mentioned thread forming process and curl process.

As a result, a seamless integrally molded bottle can 10 as shown in FIG. 1 is produced.
In the example of this embodiment, the neck portion 8, concave curved portion 22, inclined portion 21, etc. of the mouthpiece portion 5 are formed using a die processing tool in the necking step. Alternatively, a rotary processing tool (forming rollers such as a core roller and an outer roller) may be used before and after the thread forming process.

In a process subsequent to the throttle process, the inside of the bottle can 10 is filled with contents such as a beverage, and a cap 15 having a capped cylinder shape is fitted onto the mouthpiece 5 by a capper (cap fitting device). be done. Thereby, the capped bottle can 20 is manufactured.
Specifically, as shown in FIGS. 2 and 4, the cap 15 is first placed on the cap 5, and a load (axial load) is applied downward from above the cap 15 using a pressure block (not shown). A sealing material provided on the lower surface of the top wall (ceiling wall) is pressed from above against the curled part 9 of the mouthpiece part 5 to bring the bottle can 10 into a sealed state. In this sealed state, a screw roll (not shown) is pressed radially inward against the peripheral wall of the cap 15 and rolled in the circumferential direction around the can axis O. , a female thread shape that follows the male thread shape of the threaded portion 6 is formed. Further, while applying a radially inward load (lateral load) with the hem roll 50 to the lower end of the peripheral wall of the cap 15, the hem roll 50 is rolled all the way around the can axis O, The lower end of the peripheral wall of the cap 15 is hemmed. As a result, as shown in FIGS. 3 and 5, the lower end of the peripheral wall of the cap 15 fits tightly into (the lower part of) the bulge 7.
In this way, the cap 15 is attached to the mouthpiece 5 with the contents of the bottle can 10 sealed. Further, this sealed state is maintained until the cap 15 is removed from the mouthpiece 5 and opened.

In the example of this embodiment, when the lower end of the circumferential wall of the cap 15 is hemmed by the hem roll 50, the tip of the hem roll 50 (the outer periphery flange) contacts the inclined portion 21, as shown in FIG. be brought into contact with By abutting the hem roll 50 against the inclined portion 21, a hem roll trace (not shown) extending around the can axis O is formed on the inclined portion 21. Further, the hem roll 50 is not brought into contact with the neck portion 8, so that the hem roll traces are not formed on the neck portion 8.
In other words, in the example of this embodiment, when the lower end of the circumferential wall of the cap 15 is hemmed by the hem roll 50, the tip of the hem roll 50 is actively brought into contact with the inclined portion 21. This prevents the tip of the neck portion 8 from hitting the neck portion 8.

According to the bottle can 10 and the capped bottle can 20 according to the present embodiment described above, the mouthpiece 5 of the can body 1 has the inclined part 21, and the inclined part 21 is located below the bulging part 7. The cap 15 is disposed adjacent to the lower end of the circumferential wall of the cap 15 fitted to the bulge 7, and is formed to be inclined radially inward as it goes downward. That is, unlike the conventional bottle can 100 shown in FIG. 7, the cylindrical neck 104 parallel to the can axis O is not arranged below the bulge 103 adjacent to it, but in this embodiment, as shown in FIG. As shown, a tapered inclined part 21 is provided between the bulging part 7 and the neck part 8 and gradually extends radially inward as it goes downward.
In a longitudinal cross-sectional view of the bottle can, the inclined portion 21 is disposed outside the extension line L of the lower end of the bulging portion 7 (the outside of the can, which may also be referred to as the outside in the radial direction). In the example of this embodiment, the hem roll 50 (the tip thereof) that hems the lower end of the peripheral wall of the cap 15 is brought into contact with the inclined portion 21 . In other words, the hem roll 50 abuts not on the neck portion 8 but on the inclined portion 21 .

Therefore, when hemming the lower end of the circumferential wall of the cap 15 onto (the lower part of) the bulging portion 7 with the hem-rolling roll 50 at the time of capping, the hem-rolling roll 50 also contacts the inclined portion 21 along with the circumferential wall of the cap 15. Since the sloped portion 21 slopes inward in the radial direction and escapes, the pressing force (lateral load) applied to the sloped portion 21 from the hem roll 50 can be reduced.
Specifically, compared to the configuration of FIG. 7 in which the neck portion 104 is disposed adjacent to the lower part of the bulging portion 103 as in the prior art, in the present embodiment shown in FIG. 21 can be placed radially inward than the conventional neck 104. Since the hem roll 50 is biased radially inward by the spring force, the tip (flange on the outer peripheral edge) of the hem roll 50 is pressed against the inclined portion 21 that has escaped radially inward. By doing so, the pressing force that the inclined portion 21 receives from the hem roll 50 can be suppressed to a small level. Further, since the inclined portion 21 is inclined, the pressing force of the hem wrapper roll 50 can be dispersed in a direction other than the radially inner side, such as downward in the can axis O direction. Further, it is possible to prevent the hem roll 50 from coming into contact with portions other than the inclined portion 21 (such as the concave curved portion 22 and the neck portion 8 located below the inclined portion 21). Therefore, due to these synergistic effects, deformation of the neck portion 8 can be effectively suppressed.

Here, the radially inward pressing force that the neck portion 8 receives from the hem roll 50 and the amount of deformation of the neck portion 8 in response to this will be explained. The amount of deformation (the amount of change in radius) ΔR of the neck portion 8 can be expressed by the following equation based on material mechanics.
△R=(R ² /tE)×P
In the above equation, P is the external pressure (the pressure that the neck part 8 receives from the hem roll 50 toward the inside in the radial direction), R is the radius (inner diameter) of the neck part 8, t is the thickness (wall thickness) of the neck part 8, and E is Young's modulus. From the above equation, it can be seen that when the external pressure P, the thickness t, and the Young's modulus E are constant, the amount of deformation ΔR of the neck portion 8 is proportional to the square of the radius R of the neck portion 8. In other words, as the radius R of the neck 8 becomes smaller, the amount of deformation ΔR of the neck 8 also becomes smaller in proportion to the square of the radius R (in fact, when the radius R changes, the thickness t also changes slightly. However, since it is a minute amount, it will not be considered here).

In this embodiment, the outer diameter of the neck portion 8 is reduced because the inclined portion 21 is formed above the neck portion 8 as described above. That is, compared to the conventional bottle can 100 shown in FIGS. 6 and 7, the bottle can 10 of the present embodiment shown in FIGS. Even if the pressing force received from the neck part 50 is the same as in the conventional case, the amount of deformation ΔR of the neck part 8 is reliably reduced, and deformation of the neck part 8 is prevented.

As described above, according to the bottle can 10 and the capped bottle can 20 of the present embodiment, even if the can is made thinner, the neck 8 is deformed by the forming load (axial load and lateral load) during capping. This can definitely be prevented.

Further, in this embodiment, since the difference between the maximum outer diameter (diameter) of the bulging portion 7 and the minimum outer diameter (diameter) of the neck portion 8 is 2.5 to 10.0 mm, the following effects are achieved. .
In other words, as in the above configuration, if the difference between the maximum outer diameter of the bulging part 7 and the minimum outer diameter of the neck part 8 is 2.5 mm or more, the inclined part located between the bulging part 7 and the neck part 8 21 can be ensured sufficiently, and the hem roll 50 can be prevented from hitting the neck part 8 more reliably. Further, the radius R of the neck portion 8 is made sufficiently small, so that the amount of deformation ΔR of the neck portion 8 can be stably suppressed to a small value.
Moreover, if the above-mentioned difference is 10.0 mm or less, the formability of the inclined portion 21 is maintained well. That is, when forming the inclined portion 21 by die processing as described in the present embodiment, it is possible to prevent cracks and the like caused by the inclined portion 21 being rapidly expanded in diameter upward from the neck portion 8.
Incidentally, in order to make the above-mentioned effects even more remarkable, it is more preferable that the above-mentioned difference is 3.0 to 7.0 mm.

In addition, in this embodiment, since the angle θ at which the inclined portion 21 is inclined with respect to the can axis O is 20 to 40 degrees in a longitudinal cross-sectional view of the bottle can 10 along the can axis O direction, the following effects can be achieved. play.
That is, as in the above configuration, if the angle θ at which the inclined portion 21 is inclined with respect to the can axis O is 20° or more in a longitudinal cross-sectional view including the can axis O of the bottle can 10, the inclined portion 21 is sufficiently inclined. It is possible to more reliably prevent the hem roll 50 from strongly hitting the inclined portion 21 when the hem roll 50 is forced (to lie down).
In addition, if the angle θ at which the inclined portion 21 is inclined with respect to the can axis O is 40° or less in the vertical cross-sectional view, the inclined portion 21 is tilted too much (overly laid down), and the cap portion 5 It is possible to prevent the load capacity (especially axial load capacity) from decreasing.

Moreover, in this embodiment, since the inclined part 21 is formed in a straight line in the longitudinal cross-sectional view of the bottle can 10, it is easy to connect the inclined part 21 to the lower end (straight part 19) of the bulging part 7 without any step. .

Further, in this embodiment, the bulging portion 7 and the inclined portion 21 are connected so as to touch each other at the connecting portion in a longitudinal cross-sectional view of the bottle can 10, so that it is easy to mold the cap portion 5, and It is possible to prevent the base portion 5 from buckling and deforming starting from the connecting portion between the protruding portion 7 and the inclined portion 21. Further, the appearance (beauty) of the cap portion 5 is good.

Further, in this embodiment, since the distance A along the can axis O direction from the lower end of the peripheral wall of the cap 15 to the lower end of the inclined portion 21 is 2 to 6 mm, the following effects are achieved.
That is, as in the above configuration, if the distance A in the can axis O direction between the lower end of the peripheral wall of the cap 15 and the lower end of the inclined portion 21 is 2 mm or more, the hem roll 50 can be more reliably prevented from hitting the neck portion 8. can. This is because the vertical thickness of the outer peripheral edge (flange) of the hem roll 50 is 2 mm or more.
Further, if the distance A is 6 mm or less, it is possible to suppress a reduction in the axial load resistance of the inclined portion 21 due to the inclined portion 21 becoming too long.
In addition, in the bottle can 10 before the cap 15 is attached, the distance in the can axis O direction from the lower end 7a of the bulging part 7 to the lower end of the inclined part 21 is 2.2 to 6.2 mm, so the same effect as described above is achieved. Effects can be obtained.

Further, in this embodiment, the hem roll 50 is brought into contact with the inclined part 21 during capping, so that a hem roll trace extending around the can axis O is formed on the inclined part 21. In this embodiment, as described above, since the pressing force of the hem roll 50 on the inclined portion 21 can be kept small, the hem roll traces can be made less noticeable. In addition, deformation of the neck portion 8 is also suppressed.

Further, in this embodiment, since the hem roll 50 does not come into contact with the neck 8 during capping, no hem roll traces extending around the can axis O are formed on the neck 8. Since no hem roll marks are formed on the neck portion 8, the beauty of the cap portion 5 can be improved. In addition, deformation of the neck portion 8 is more reliably prevented.

Further, in this embodiment, in a vertical cross-sectional view of the bottle can 10, the angle at which the lower part of the bulging portion 7 is inclined with respect to the can axis O (the angle formed between the can axis O and the extension line L; the same applies hereinafter) ) is 36° or more, the lower part of the bulging portion 7 is sufficiently inclined (flattened), the circumferential wall of the cap 15 is reliably wrapped around the hem, and the cap 15 slips out completely (the base upward separation from portion 5) does not occur.
In addition, in the longitudinal cross-sectional view, since the angle at which the lower part of the bulging part 7 is inclined with respect to the can axis O is 50 degrees or less, the lower part of the bulging part 7 is tilted too much (overly laid down). ), it is possible to prevent the load capacity (especially the capacity for axial load) of the bulging portion 7 from being reduced.

Note that the present invention is not limited to the above-described embodiments, and various changes can be made without departing from the spirit of the present invention, for example, as explained below.

In the embodiment described above, between the bulge part 7 and the shoulder part 4, there is provided an inclined part 21, a concave curved part 22, a neck part 8, and a concave curved part adjacent to the lower part of the neck part 8. However, it is not limited to this. That is, below the bulging part 7, there is a slope part 21 which slopes radially inward as it goes downward, and a neck part 8 which is arranged below the slope part 21 and has a smaller diameter than the slope part 21. , and other components may have shapes other than those described in the above embodiments.

Furthermore, in the above-described embodiment, the inclined portion 21 is linear in the vertical cross-sectional view of the bottle can 10 along the can axis O direction, but the present invention is not limited to this. In a longitudinal cross-sectional view including the can axis O, the inclined portion 21 may have a concave curved shape. In this case, the inclined portion 21 is formed in a concave curved shape that is concave toward the inside (radially inside) of the can. Formability is further improved by forming the inclined portion 21 in a concave curved shape when viewed in longitudinal section of the bottle can.

Further, in a longitudinal cross-sectional view including the can axis O, the inclined portion 21 may be formed in a convex curved shape instead of being formed in a straight line or a concave curved shape. In this case, the inclined portion 21 has a convex curved shape that swells toward the outside (radially outside) of the can.
Alternatively, the inclined portion 21 may have a composite shape, for example, a combination of two or more of a straight line, a concave curve, and a convex curve, when viewed in longitudinal section of the bottle can.

Furthermore, in the above-described embodiment, when the lower end of the circumferential wall of the cap 15 is hem-rolled to the bulging portion 7 by the hem-rolling roll 50, the hem-rolling roll 50 contacts the inclined portion 21 as well as the circumferential wall of the cap 15. , the reference example of the present invention is not limited to this. The hem roll 50 does not need to be in contact with the inclined portion 21. In this case, no hem roll traces are formed not only on the neck portion 8 but also on the inclined portion 21.

Further, in the above-described embodiment, the straight part 19 is arranged at the lower end of the bulging part 7 in the longitudinal cross-sectional view of the bottle can, and the inclined part 21 is located on the outside (the can However, a convex curved part may be arranged at the lower end of the bulging part 7 instead of the straight part 19. In this case, the extension line L of the lower end of the bulge 7 refers to a tangent at the connection point (boundary point, inflection point) between the bulge 7 and the inclined portion 21 (the tangent line means at least the bulge 7).

Further, in the above-described embodiment, the bulging portion 7 and the inclined portion 21 are connected to each other so as to touch each other at the connecting portion in the longitudinal cross-sectional view of the bottle can 10, but the present invention is not limited to this. isn't it. For example, in a longitudinal cross-sectional view of the bottle can, the connecting portion between the bulging portion 7 and the inclined portion 21 may be formed in a bent shape (at an obtuse angle).

Further, in the above-described embodiment, the explanation was given using the bottle can 10 having a diameter of 38 mm, in which the maximum outer diameter (diameter) of the bulging part 7 of the cap part 5 was about 38.0 mm, but the description is not limited to this. It is not something that will be done. That is, the present invention is applicable to, for example, bottle cans having a maximum outer diameter (diameter) of about 33.0 mm or 28.0 mm at the bulging part of the mouthpiece, and the bulge between 28 mm and 38 mm. It may be the diameter of the part.

Furthermore, in the above-described embodiment, the bottle can 10 is described as an example in which the can body 1 and the can bottom 2 are integrally formed. It may be formed in the body, and it may be a combination of these.

In addition, each structure (component) explained in the above-mentioned embodiments, modifications, notes, etc. may be combined without departing from the spirit of the present invention. Changes are possible. Furthermore, the present invention is not limited by the embodiments described above, but only by the scope of the claims.

The bottle can and capped bottle can of the present invention can prevent neck deformation due to molding load during capping even when the can is made thinner. Therefore, it has industrial applicability.

1 Can body 2 Can bottom 5 Mouth part 6 Threaded part 7 Bulging part 7a Lower end of bulging part 8 Neck part 10 Bottle can 15 Cap 19 Straight part (lower part of bulging part)
20 Bottle can with cap 21 Inclined part 50 Hem roll A Distance L Extension line O Can axis θ Angle

Claims (10)

A bottomed cylindrical bottle can comprising a can body and a can bottom,
The mouthpiece of the can body is
a threaded part;
The lower end of the circumferential wall of a cylindrical cap that is disposed below and adjacent to the threaded portion, bulges outward in the radial direction, extends over the entire circumference around the can shaft, and is attached to the mouthpiece portion is hemmed. a bulge;
a sloped portion that is arranged below and adjacent to the bulged portion and slopes radially inward as it goes downward;
a neck portion disposed below the slope portion and having a smaller diameter than the slope portion;
The difference between the maximum outer diameter of the bulge and the minimum outer diameter of the neck is 2.5 to 10.0 mm,
A bottle can in which the minimum outer diameter of the neck is 28 to 35.5 mm . The bottle can according to claim 1,
A bottle can with a bottle diameter of 38mm. The bottle can according to claim 1 or 2,
The bottle can, in a longitudinal cross-sectional view including the can axis, the angle at which the inclined portion inclines with respect to the can axis is 20 to 40°. The bottle can according to any one of claims 1 to 3,
The inclined portion is linear in a longitudinal cross-sectional view including the can shaft,
The amount of displacement in the radial direction per unit length of the inclined portion along the can axis direction is smaller than the amount of displacement of the lower portion of the bulging portion. The bottle can according to any one of claims 1 to 3,
A bottle can in which the inclined portion has a concave curve shape when viewed in a longitudinal section including the can axis. The bottle can according to any one of claims 1 to 5,
A bottle can, in which the bulging portion and the inclined portion are connected so as to touch each other at a connecting portion when viewed in a longitudinal section including the can axis. A bottomed cylindrical bottle can having a can body and a can bottom;
A bottle can with a cap, comprising: a cylindrical cap attached to the mouthpiece of the can body;
The base portion is
a threaded part;
a bulging portion disposed below and adjacent to the threaded portion, bulging radially outward and extending all around the can axis, and around which the lower end of the peripheral wall of the cap is hemmed;
a sloped portion that is arranged adjacently below the lower end of the peripheral wall of the cap and slopes radially inward as it goes downward;
a neck portion disposed below the slope portion and having a smaller diameter than the slope portion;
The difference between the maximum outer diameter of the bulge and the minimum outer diameter of the neck is 2.5 to 10.0 mm,
A bottle can with a cap , wherein the minimum outer diameter of the neck is 28 to 35.5 mm . The bottle can with a cap according to claim 7,
A bottle can with a cap, wherein a distance along the can axis direction from a lower end of the peripheral wall of the cap to a lower end of the inclined portion is 2 to 6 mm. The bottle can with a cap according to claim 7 or 8,
A bottle can with a cap, in which a hem roll trace extending around the can axis is formed on the inclined part. The bottle can with a cap according to any one of claims 7 to 9,
A bottle can with a cap in which a hem roll mark extending around the can axis is not formed on the neck portion.

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