JP7126459B2 - bottle can - Google Patents

Description

TECHNICAL FIELD The present invention relates to a bottle- can having a threaded portion to which a cap is screwed.

2. Description of the Related Art As a container to be filled with a content such as a beverage, there is known a container in which a metal cap is screwed onto a threaded portion formed in an opening of a bottle-shaped can (bottle can). For this type of bottle-can, the shapes of the threaded portion and the curled portion formed at the mouth portion are important in order to ensure good sealing performance with the cap.

For example, in the threaded metal can disclosed in Patent Document 1, when the cap is screwed together, the outer peripheral surface of the curled portion formed at the upper end of the mouth portion is formed so that it bites into the packing (liner) on the top surface of the cap to seal it. is subjected to a curl crushing process to form a flat portion. By this curl crushing process, the apex of the curled portion is formed into an arcuate surface that is slightly convex upward. This threaded metal can improves the sealing performance by making the packing and the curled portion tightly adhere to each other.

Japanese Patent Application Laid-Open No. 2001-213417

However, further improvements are required to increase the sealing performance as materials become thinner and the like. The bottle can of Patent Document 1 has high sealing performance, but when the wall thickness of the bottle can is reduced or the hardness of the liner is decreased, the sealing performance is sometimes deteriorated. Especially for bottle cans with caps, which are filled with contents in thin bottle cans and capped, the radius of curvature at the top of the crushed curled portion becomes small, and the liner bites into the liner more than intended. In addition, it was found that localized thin portions of the liner are formed and the liner hardens after retort sterilization.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to further improve the sealing performance of a bottle-can to which a cap is screwed.

The bottle can of the present invention has a curled portion formed on the outer peripheral portion of the mouth by folding the open end radially outward, and a threaded portion formed below the curled portion in the axial direction of the can. have
The outer peripheral surface of the curled portion includes, in a longitudinal section along the can axial direction, a zenith folded portion formed by folding back a curved surface that is continuous from the upper end of the curled portion and convexes radially outward, and the zenith. It has an outer bent portion that is continuous with the folded lower end of the folded portion and is bent radially inward so as to be convex, and a curled end that is continuous from the outer curved portion, and the inner peripheral surface of the curled portion. A portion continuous with the inner peripheral end of the zenith folded portion is formed on a curved surface convex radially inward, and the zenith folded portion has a maximum outer diameter D1 of 32.0 mm or more and 35.0 mm or less. The curled end portion is formed to have an outer diameter smaller than the maximum outer diameter of the zenith folded portion, and the outer peripheral surface of the lower end of the curled portion extends downward in the can axial direction from the outer bent portion. It is bent so as to be convex toward the radial direction outward while gradually decreasing in diameter inward in the radial direction according to Two radially outwardly convex portions are formed on the upper and lower portions of the outer peripheral surface via the outer bent portion, and the inner peripheral surface of the curled portion is formed by the The lower end of the convex curved surface continuous with the inner peripheral end of the zenith folded portion extends radially outward from the portion of the curved surface that protrudes most radially inward, and extends inward from the lower end of the curved surface. The upright portion extending in the can axis direction is continuous via the bent portion .
In this case, the inner peripheral surface of the curled portion is radially outside a portion of the curved surface where the lower end of the convex curved surface, which is continuous with the inner peripheral end of the zenith folded portion, protrudes most radially inward. It is preferable that the upright portion extending in the can axial direction from the lower end of the curved surface through the inner bent portion is continuous.
In order to manufacture this bottle can, an opening cylindrical portion is formed along the can axial direction at the opening end of the intermediate molded body to be the bottle can, and the end portion of the opening cylindrical portion is radially outward. After forming a folded portion that is opened and folded back, the zenith folded portion is formed on the tip side in the axial direction of the can by pressing the lower portion of the folded portion from the tip side in the can axial direction from the radially outer side with a roll. is formed, and the outer bent portion and the curled end portion are formed in the portion pressed by the roll.
According to this manufacturing method, the can can be manufactured by a simple process of folding back the end portion of the opening cylindrical portion and then pressing it from the radially outward side while leaving the tip side in the can axial direction.

According to this bottle-can, when the cap is screwed, the liner of the cap is press-contacted in the can axial direction with the upper surface of the zenith folded portion of the curled portion. Also, during capping, the peripheral edge of the top surface of the cap is drawn by the pressure block, so that a load acts inward in the axial direction and radial direction of the can. The outer peripheral surface of the zenith folded portion is also in close contact with the liner.
Therefore, the upper surface of the zenith folded portion and the outer peripheral surface are in close contact with the liner, and the sealing performance can be improved.
As for the liner of the cap, it is sheet-shaped as a whole, but the outer peripheral part that contacts the curled part is formed into a thick seal part, and the seal part that contacts the curled part has two A configuration in which parallel ridges are formed along the circumferential direction and the curled portion is fitted between both ridges can be applied.

The present invention also provides a capped bottle-can obtained by attaching a cap to the bottle-can described above, wherein the cap includes a sliding layer on the inner surface of the top surface portion that is slidable with the top surface portion; A liner is formed by laminating a sealing layer that contacts the curled portion, and an inner ridge and an outer ridge are formed in a double annular shape on an outer peripheral portion of the sealing layer, and the outer ridge is a double ring. , is pressed against the outer peripheral surface of the zenith turn-up portion, and is in close contact with the outer peripheral surface of the outer bent portion and the outer peripheral surface of the curled end portion, and the inner ridge is in close contact with the curved surface of the ridge .

In this capped bottle-can, the zenith folded portion of the curled portion of the bottle-can is fitted between the inner and outer ridges of the liner of the cap, and the inner peripheral surface of the zenith folded portion extends from the inner peripheral surface to the upper surface and the outer peripheral surface. It can adhere to the liner to the maximum, ensuring high sealing performance.

According to the bottle can according to the present invention, it is possible to improve the sealing performance between the curled portion formed at the mouth and the cap.

FIG. 4 is a partial cross-sectional view showing the bottle-can and the cap material of the present invention, showing a state before capping the bottle-can with the cap material. FIG. 3A is a half cross-sectional view of the vicinity of the opening, showing a state before capping and FIG. 4B showing a state after capping. 3 is an enlarged cross-sectional view of the vicinity of the curl portion shown in FIG. 2(b); FIG. FIG. 4 is a vertical cross-sectional view showing the first half of the bottle-can manufacturing process in order from (a) to (c); FIG. 4 is a vertical cross-sectional view showing the second half of the bottle-can manufacturing process in order from (a) to (c). It is an enlarged vertical cross-sectional view which shows the shaping|molding process of a curl part in order of (a) and (b). It is a front view which shows a bottle-can manufacturing apparatus typically. FIG. 8 is a cross-sectional view taken along line AA of FIG. 7; It is a schematic diagram which shows the principal part of a capping apparatus. It is a half cross-sectional view of the vicinity of the opening, to which a modified cap is applied, in which (a) shows a state before capping and (b) shows a state after capping. 10B is an enlarged cross-sectional view of the vicinity of the curled portion shown in FIG. 10B; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The bottle can 10 is made of a thin sheet metal of aluminum or an aluminum alloy, and as shown in FIG. a tapered cylindrical portion 13 whose diameter gradually decreases upward in the can axial direction from the shoulder portion 12; The mouth portion 14 includes a bulging portion 15 formed at the upper end of the tapered cylindrical portion 13, a threaded portion 16 continuing to the upper end of the bulging portion 15, and gradually shrinking upward from the upper end of the threaded portion 16. It has a diameter-reduced portion 17 and a curled portion 18 formed at the upper end of the diameter-reduced portion 17 by bending the open end radially outward. 2(a), the cap member 3 is put on the mouth portion 14, and the liner 40 on the inner surface of the top surface portion 31 of the cap member 3 is pressed against the curled portion 18, and along the threaded portion 16, the cap member 40 is pressed. The cylindrical skirt portion 33 of the material 3 is threaded, and the lower end of the skirt portion 33 is engaged with the bulging portion 15 to form the cap 30 and seal the mouth portion 14 (FIG. 2). (b) and see FIG. 3). In the following description, the vertical direction is defined by the orientation shown in FIG.

The curled portion 18 is formed continuously with the diameter-reduced portion 17 formed at the lower position in the can axial direction, and as shown in FIGS. An upright portion 21 that is bent at the upper end of the portion 17 and extends along the can axial direction, an inner bent portion 22 that is bent at the upper end of the upright portion 21 so as to protrude radially inward, and the inner bent portion 22 A zenith folded portion 23 that is folded back by a continuous curved surface that is convex outward, an outer bent portion 24 that bends toward the can axis direction at the folded lower end of the zenith folded portion 23, and from the outer bent portion 24. It has a curled end 25 which extends in the can axial direction and faces the outer peripheral surface of the upright portion 21 .

In this case, as shown in FIG. 6B, the zenith folded portion 23 is formed to have an outer diameter D2 smaller than the maximum outer diameter D1 of the zenith folded portion 23 at its folded lower end (substantially the same position as the outer bent portion 24). (substantially also the outer diameter D2 of the curled end 25). Further, the width W1 in the direction orthogonal to the can axial direction (the distance from the inner peripheral edge to the outer peripheral edge of the zenith folded portion 23) is the radial distance W2 from the inner peripheral surface of the upright portion 21 to the outer peripheral surface of the curled end portion 25. formed larger than Therefore, the inner peripheral portion of the zenith folded portion 23 protrudes radially inward from the inner peripheral surface of the upright portion 21 , and the outer peripheral portion of the zenith folded portion 23 protrudes radially outward from the outer peripheral surface of the curled end portion 25 . ing. The zenith folded portion 23 is formed such that the radius of curvature R of its outer surface is 0.8 mm or more and 2.5 mm or less. The curvature radius R of the upper surface of the zenith folded portion 23 may be a single curvature radius, or may be a series of circular arcs having different curvature radii. In addition, although some cylindrical surfaces 23a and 23b are formed on the inner and outer peripheral surfaces of the zenith folded portion 23, the cylindrical surfaces 23a and 23b are absent, and the entire surface is curved with the radius of curvature R described above. may be formed in

Other dimensions of the bottle can 10 having such a shape are not necessarily limited. (wall thickness) is 0.110 mm or more and 0.125 mm or less, the thickness from the screw portion 16 to the curl portion 18 is 0.210 mm or more and 0.230 mm or less, the outer diameter of the curl portion 18 (the maximum outer diameter of the zenith folded portion 23 ) D1 is 32.0 mm or more and 35.0 mm or less, width W1 is 1.5 mm or more and 3.0 mm or less, and height H of the zenith folded portion 23 in the can axial direction is 2.0 mm or more and 4.0 mm or less. .

On the other hand, the cap 30 is made of a thin sheet metal of aluminum or an aluminum alloy. It has a plate-like top surface portion 31 , a skirt portion 33 extending vertically downward from the outer peripheral edge of the top surface portion 31 , and a liner 40 provided on the inner surface of the top surface portion 31 . In the skirt portion 33, at a position close to the top surface portion 31 of the upper portion thereof, a knurled recess portion 34 that imparts a frictional force to the hand when opening the bottle, and a vent hole 35 for releasing the internal pressure when opening the bottle are formed in the circumferential direction. The upper pieces 35a of the vent holes 35 are formed in a state of being pushed radially inward, so that the liner 40 is arranged between the upper pieces 35a and the top surface portion 31 to prevent them from coming off. be.
A slit 36 is formed intermittently in the circumferential direction at the lower end of the skirt portion 33 . A plurality of bridges 37 formed in the upper portion 33a and the lower portion 33b of the cylinder are connected to each other.

The liner 40 is entirely made of synthetic resin and has a disc shape, and is rotatably installed with respect to the cap member 3 . Specifically, the liner 40 includes a sealing layer 41 made of elastomer resin or the like and having a sealing function, and a top surface portion 31 of the cap member 3 made of polypropylene or the like and having hardness higher than that of the sealing layer 41. and a sliding layer 42 that can slide. The sealing layer 41 has an outer diameter smaller than that of the sliding layer 42, and a thick sealing portion 43 is annularly formed on the outer peripheral portion. The seal portion 43 is a portion that comes into close contact with the curled portion 18 of the bottle can 10 .

In order to manufacture the bottle can 10, first, an aluminum plate material is punched and drawn to form a cup 1 having a relatively large diameter and a shallow depth as shown in FIG. 4(a). Drawing and ironing (DI processing) are applied to form a cylindrical body 2 having a predetermined height as shown in FIG. By this DI processing, the bottom portion of the cylindrical body 2 is molded into the shape of the bottom portion 10 a of the final bottle can 10 .

Next, the bottle-can manufacturing apparatus 50 shown in FIGS. 7 and 8 is used to manufacture the bottle-can 10 . The bottle-can manufacturing apparatus 50 will be described below. This bottle-can manufacturing apparatus 50 is for processing the cylindrical body 2 formed as described above into the final shape of the bottle-can 10, and the shape of the can changes according to the progress of the processing. However, hereinafter, when the shape of the can is not particularly limited from the cylindrical body 2 to the bottle can 10, the intermediate molded body 4 will be described.

This bottle-can manufacturing apparatus 50 includes a work holding section 51 for holding a plurality of intermediate molded bodies 4 arranged horizontally in the can axial direction, and a plurality of molding tools 52 for performing various molding processes on these intermediate molded bodies 4. and a driving portion 54 for driving both holding portions 51 and 53 . A work holding side of the work holding portion 51 holding the intermediate formed body 4 and a tool holding side of the tool holding portion 53 holding the forming tool 52 are arranged to face each other.

The workpiece holding portion 51 has a structure in which a plurality of holding devices 57 for holding the intermediate molded body 4 are arranged in a ring along the circumferential direction on the surface of a disk 56 supported by a support shaft 55 facing the tool holding portion 53 . It is As the disk 56 is intermittently rotated about the support shaft 55 by the drive section 54 , the bottom portion of the preform 4 supplied from the supply section 58 via the supply-side star wheel 59 is pushed into the holding device 57 . They are held one by one and conveyed in the circumferential direction of the disc 56 . The intermediate molded body 4 is molded by each molding tool 52 of the tool holding section 53 while being conveyed by the disk 56, and then sequentially discharged as the molded bottle can 10 to the discharge section 61 via the discharge side star wheel 60. .

In the tool holding portion 53, a plurality of various forming tools 52 are annularly arranged along the circumferential direction on the surface of the disk 63 supported by the support shaft 62, which faces the work holding portion 51. The disk 63 is supported by the driving portion 54. It is configured to advance and retreat in the axial direction of the shaft 62 . The support shaft 62 is coaxially provided inside the support shaft 55 .

The tool holding portion 53 has a plurality of necking dies for reducing the diameter (neck-in processing) of the opening of the intermediate molded body 4, a thread forming tool for forming a threaded portion, and a curling portion 18 for forming the curl portion 18. A plurality of forming tools 52 are provided for performing processing corresponding to each processing step, such as a curl portion forming tool. These molding tools 52 are annularly arranged on a disk 63 in the order of processes.

The intermittent rotation stop position of the work holding portion 51 (disk 56) about the axis of the support shaft 55 is such that the can shaft of each intermediate molded body 4 with the opening facing the tool holding portion 53 is aligned with each forming tool. 52 are set so as to coincide with the respective central axes. Then, by intermittent rotation of the disk 56 by the drive unit 54, each intermediate compact 4 is rotationally moved to a position facing each molding tool 52 for the next process, and processed in the next step.

That is, when the tool holding portion 53 advances and the work holding portion 51 and the tool holding portion 53 approach each other, each forming tool 52 processes the intermediate compact 4 according to each process, and both holding portions 51 , 53 are separated from each other, the workpiece holder 51 is rotated so that the molding tool 52 for the next process faces each intermediate compact 4 . In this manner, the shoulder portion 12, the tapered cylinder portion 13, and the mouth portion 14 are sequentially formed in the intermediate molded body 4 by repeating the operation of the two holding portions 51 and 53 approaching each other for processing, separating and rotating. and the bottle can 10 is formed.

In this case, first, as shown in FIG. 4(c), an intermediate molded body 4 having a straight cylindrical portion 5 at its upper end is formed.
Then, as shown in FIG. 5A, after the diameter of the cylindrical portion 5 is increased again from a position slightly above the upper end of the tapered cylindrical portion 13, the diameter of the upper portion is reduced again except for the lower end portion of the increased diameter portion. For example, the tubular portion 6 before threading is formed. Then, the tubular portion 6 is threaded to form a threaded portion 16 as shown in FIG. 5(b). In the state in which the threaded portion 16 is formed, a diameter-reduced portion 17 gradually decreasing in diameter as it goes upward and a straight open cylindrical portion 8 extending along the can axial direction are formed on the threaded portion 16 . formed.
Then, the open tubular portion 8 is folded back radially outward to form a folded portion 19 with its leading end directed toward the bottom of the can (Fig. 5(c)).

The processing of the folded portion 19 is performed by two steps: a folding step of folding the opening cylindrical portion 8 so as to make a U-turn, and a zenith folded portion forming step of forming the zenith folded portion 23 from the folded portion thus formed. .
First, in the folding process, a widening die 52A and a folding die 52B indicated by two-dot chain lines in FIG. The expanding mold 52A and the folding mold 52B are each formed in a roll shape and are rotatable as indicated by arrows, and are supported so as to be rotatable along the circumferential direction of the opening cylindrical portion 8. By pressing the open tubular portion 8 toward the can bottom while rotating, the open tubular portion 8 is opened outward by the expanding die 52A and then folded back by the folding die 52B.

FIG. 6(a) shows the folded portion 19 formed in this way, and the tip portion in the can axial direction is formed into an arcuate surface that protrudes upward, and the rest of the opening cylindrical portion 8 is formed below it. The portion and the end 19a of the folded portion 19 are arranged substantially parallel to each other. The upwardly convex arcuate surface at the tip in the can axis direction forms the upper surface of the zenith folded portion 23 .
Next, in the zenith folded portion forming step, as a forming tool 52, as shown by a two-dot chain line in FIG. The folded portion 19 is processed using the outer roll 52D disposed radially outward of the . Specifically, by bringing both rolls 52C and 52B closer to each other, the lower end portion of the open tubular portion 8 remaining below the folded portion 19 and the lower end portion 19a of the folded portion 19 are crushed from both sides in the plate thickness direction. By pressing and pinching, as shown in FIG. 6(b), the zenith folded portion 23 is formed above the pinched portion. An inner bent portion 22 and an upright portion 21 are formed in the portion pressed by the inner roll, and an outer bent portion 24 and a curled end portion 25 are formed in the portion pressed by the outer roll. Thus, the molding of the curled portion 18 is completed. The lower end of the curled end portion 25 is formed in a slightly bent state due to the molding marks left when the tip of the open cylindrical portion 8 is expanded by the aforementioned expansion mold 52A.

In order to apply the cap material 3 to the mouth portion 14 of the bottle can 10 manufactured in this manner and carry out the capping process, for example, a capping device having a plurality of capping heads 70 as shown in FIG. 9 is used. Then, the cap material 3 is attached to the bottle can 10 by the capping head 70 .
This capping head 70 comprises a pressure block 62 having a cap retainer 61, a first roll 63 as an RO roll (roll-on roll), and a second roll 64 as a PP roll (Pilfer proof roll). . The pressure block 62 has a cylindrical lower end and is relatively movable in the can axial direction with the cap presser 61 disposed inside thereof. ing. Also, the first roll 63 and the second roll 64 are supported so as to be able to turn around the pressure block 62 and move in the can axis direction.

Then, in a state in which the mouth portion 14 of the bottle can 10 is covered with the cap material 3, the cap retainer 61 presses the top surface portion 31 of the cap material 3, and in this state, the pressure block 62 is applied to the outer peripheral portion of the top surface portion 31. The stepped portion 31a is formed by drawing. Also, the first roll 63 forms the cap threaded portion 38 on the cap material 3, and the second roll 64 rolls the cylindrical lower portion 33b into the bulging portion 15 to fix it.
By capping in this manner, the liner 40 within the cap 30 is pressed against the mouth 14 of the bottle-can 10 to seal the interior.

In the bottle can 10 configured as described above, the entire outer surface of the zenith folded portion 23 in the curled portion 18 is formed into a curved surface that is convex outward, so that the load in the can axial direction during capping is reduced. As a result, the liner 40 is brought into close contact with the curved upper surface of the zenith folded portion 23 , and the peripheral edge portion of the top surface portion 31 of the cap 30 is drawn by the pressure block 62 . is in close contact. Since the zenith folded portion 23 has a curved outer surface, the curved surface bites into the liner 40. However, since the curvature radius R is formed to be 0.8 mm or more and 2.5 mm or less, The liner 40 is prevented from being locally thinned, and the soundness of the liner 40 can be maintained for a long period of time.

In this way, since the zenith folded portion 23 is in close contact with the liner 40 over a wide range from the upper surface to the outer peripheral surface, the pressure of the contents in the positive pressure state (carbonated beverage, nitrogen gas-filled beverage, etc.) is increased. Even if the top surface portion 31 of the cap 30 rises and is deformed in a direction that bulges upward in the can axial direction together with the liner 40, the liner 40 is caught by the outer peripheral surface of the zenith folded portion 23, and the liner 40 is not lifted due to the increase in internal pressure. It is regulated, and the close contact state of the outer peripheral surface of the zenith folded portion 23 is maintained. Therefore, good sealing performance can be maintained.

The bottle-can configured as described above can be applied to the cap 30 having the molded liner 44 as shown in FIGS. can. In the following description and in FIGS. 10 and 11, the same reference numerals are given to the same parts as in the above-described embodiment, and the description thereof will be omitted.
FIG. 10(a) is a vertical cross-sectional view of the bottle-can 10 covered with the cap material 3, and FIG. 10(b) is a vertical cross-sectional view of the bottle-can 10 after the cap 30 is seamed.
In the liner 44, an inner ridge 46 and an outer ridge 47 are formed concentrically on the outer periphery of the sealing layer 45, and a recessed groove 48 is formed between the ridges 46 and 47. A seal portion 49 consisting of the inner ridge 46, the outer ridge 47, and the recessed groove portion 48 is formed in an annular shape.

When the cap material 3 is put on the curled portion 18 of the bottle can 10, the curled portion 18 is inserted into the concave groove portion 48 of the seal portion 49 as shown in FIG. 10(a). Then, as shown in FIGS. 10B and 11, the bottom surface of the recessed groove portion 48 is in close contact with the top surface of the zenith folded portion 23, and the pressure block 62 pushes the outer peripheral side of the top surface portion 31 of the cap member 3 toward the can bottom. A step portion 31 a is formed on the peripheral edge portion of the top surface portion 31 by drawing while being pressed against the top surface portion 31 , and the outer ridge 47 of the liner 44 is pressed against the outer peripheral surface of the zenith folded portion 23 . In addition, due to the deformation of the outer ridge 47 , the inner ridge 46 is drawn toward the curled portion 18 , and the outer peripheral surface of the inner ridge 46 comes into close contact with the inner peripheral surface of the zenith folded portion 23 .

In this case, the length L of both the ridges 46 and 47 in the can axis direction is greater than the height H of the zenith folded portion 23 (see FIG. 6(b)), and the distance between the inner surfaces of the ridges 46 and 47 The distance, that is, the width W3 of the recessed groove 48 in the direction perpendicular to the can axial direction is set equal to or smaller than the width W1 of the zenith folded portion 23 (see FIG. 6(b)).
With this setting, when the zenith folded portion 23 is fitted into the concave groove portion 48, the distance between both the ridges 46 and 47 is widened at the initial stage of the fitting, but the zenith folded portion 23 is expanded. When the upper surface bites into the bottom surface of the concave groove portion 48, the lower ends of both the protruding lines 46 and 47 reaching below the zenith folded portion 23 move toward each other due to the pressing force of the capping and the elastic force of the seal portion 49. The interval is narrowed. In addition, the peripheral edge portion 31a of the top surface portion 31 of the cap 3 also has a throttling action by the pressure block 62 . Therefore, as shown in FIGS. 10(b) and 11, from the downwardly curved surface of the zenith folded portion 23, the inner peripheral surface of the inner curved portion 22 and the outer peripheral surface of the outer curved portion 24, and further, the upright portion below them. The protrusions 46 and 47 are also in close contact with the inner peripheral surface of the portion 21 and the outer peripheral surface of the curled end portion 47 . Thus, in the bottle can 10, by applying to the cap 30 provided with the liner 44 having both the protrusions 46, 47 and the recessed groove 48, the two protrusions 46, 47 and the recessed groove 48 form a It can adhere to a wide area of the inner surface and obtain high sealing performance.

3 Cap material 4 Intermediate molded body 5 Cylindrical part 6 Cylindrical part 8 Small cylindrical part 10 Bottle can 14 Mouth part 15 Bulging part 16 Threaded part 17 Diameter reduction part 18 Curl part 21 Upright part 22 Inner bent part 23 Zenith folded part 23a , 23b cylindrical surface 24 outer bent portion 25 curled end portion 30 cap 31 top surface portion 31a stepped portion 33 skirt portion 33a cylindrical upper portion 33b cylindrical lower portion 34 knurl recess portion 35 vent hole 35a upper piece 36 slit 37 bridge 38 cap screw portion 40, 44 Liners 41, 45 Sealing layer 42 Sliding layers 43, 49 Seal portion 46 Inner ridge 47 Outer ridge 48 Groove 52A Expanding mold 52B Folding mold 52C Inner roll 52D Outer roll 62 Pressure block 63 First roll 64 second roll 65 spring 70 capping head

Claims (2)

A curled portion formed in the outer peripheral portion of the mouth by folding the open end radially outward, and a threaded portion formed below the curled portion in the can axial direction,
The outer peripheral surface of the curled portion includes, in a longitudinal section along the can axial direction, a zenith folded portion formed by folding back a curved surface that is continuous from the upper end of the curled portion and convexes radially outward, and the zenith. It has an outer bent portion that is continuous with the folded lower end of the folded portion and is bent radially inward so as to be convex, and a curled end that is continuous from the outer curved portion, and the inner peripheral surface of the curled portion. A portion continuous with the inner peripheral end of the zenith folded portion is formed into a convex curved surface directed inward in the radial direction,
The zenith folded portion has a maximum outer diameter D1 of 32.0 mm or more and 35.0 mm or less,
The curled end portion is formed to have an outer diameter smaller than the maximum outer diameter of the zenith folded portion, and the lower end of the curled portion has an outer peripheral surface that gradually increases in diameter from the outer bent portion downward in the can axial direction. It is bent so as to gradually decrease in diameter inward and convex outward in the radial direction,
Due to the convex curved surface and the convexly curved outer peripheral surface of the curled end portion, the radially outwardly convex portion is formed on the outer peripheral surface via the outer bent portion. Two are formed in the upper part and the lower part ,
The inner peripheral surface of the curled portion expands radially outward from a portion of the curved surface where the lower end of the convex curved surface, which is continuous with the inner peripheral end of the zenith folded portion, protrudes radially inward most. , and an upright portion extending in the can axial direction from the lower end of the curved surface through an inner bent portion is continuous . A capped bottle-can obtained by attaching a cap to the bottle-can according to claim 1 ,
The cap has, on the inner surface of the top surface portion, a liner in which a sliding layer slidable with the top surface portion and a sealing layer in contact with the curled portion are laminated. An inner ridge and an outer ridge are formed in a double annular shape, and the outer ridge is pressed against the outer peripheral surface of the zenith folded portion, and is pressed against the outer peripheral surface of the outer curved portion and the outer peripheral surface of the curled end. , and the inner ridge is in close contact with the curved surface of the ridge .

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