JP4990736B2 - Metal container - Google Patents

Description

  The present invention relates to a metal container made of a metal such as aluminum or an aluminum alloy and having a bottomed cylindrical shape with an opening formed at one end.

  In general, as a metal container used for a container such as a soft drink, a base part having a screw part is formed at the opening part of the metal container, and a cap that can be opened and closed is screwed to the base part. Widely-equipped bottle cans (see, for example, Patent Document 1), wide-mouth containers having a lid attached to an opening of a metal container, and the like are widely provided.

In such an opening of the metal container, in order to secure the rigidity of the opening, a curled portion is formed by winding one end of the body portion outward in the radial direction. Here, a metal cut surface is exposed at the tip of the curled portion, which causes a problem in appearance. Therefore, for example, Patent Document 2 proposes a method in which the tip (cut surface) of the curl portion is made invisible from the outside by winding the tip of the curl portion to the inside of the curl portion.
JP 2001-213417 A JP 2003-246966 A

  By the way, as described above, the cap and the lid are attached to the opening of the metal container after the contents are filled. When the cap or lid is attached in this way, the curl portion is directed in the axial direction and the radially inward direction of the metal container so that the seal portion provided on the cap or lid is in close contact with the curl portion. Load. At this time, for example, in the metal container described in the cited document 1, since the tip of the curled portion is in contact with the tapered surface of the trunk portion, the tip of the curled portion moves along the tapered surface, and the curled portion is deformed. Resulting in. Further, for example, in the metal container described in the cited document 2, since the tip of the curled portion is caught, the curled portion is further deformed by being further wound inside the curled portion by the load.

In addition, there was a risk that the curled part could be deformed by an external impact such as dropping, even when the cap or cover was not attached. The seal portion and the curled portion are not in close contact with each other, and the sealing performance is lowered. Therefore, there is a demand for a metal container having a curled portion that is strong against load and impact and is difficult to deform.

The present invention was made in view of the above circumstances, even if a load or impact is applied to the curl portion, and an object thereof is to provide a metal container may never curl portion is easily deformed .

In order to solve the above-described problems, a metal container according to the present invention has a cylindrical body extending along an axis, an opening is provided at one end of the body, and a bottom is provided at the other end. A metal container having a bottomed cylindrical shape, wherein a curled portion is formed in the opening portion by folding one end of the body portion radially outward, and an outer peripheral surface of the body portion Is provided with a locking portion for locking the tip of the curled portion, the locking portion being a locking groove recessed inward in the radial direction, and the tip of the curled portion is It is characterized in that it is housed inside the locking groove .

According to the metal container having this configuration, since the locking portion that locks the tip of the curl portion is provided on the outer peripheral surface of the trunk portion, the external portion due to load or dropping when the cap or the lid is attached is provided. When the curled portion is about to be deformed by an impact from the front end, the leading end of the curled portion is locked to the locking portion formed on the outer peripheral surface of the trunk portion, and movement of the leading end of the curled portion is restricted. Thereby, a deformation | transformation of a curl part can be suppressed.
The locking portion formed on the outer peripheral surface of the body portion only needs to have a shape capable of locking the tip of the curled portion, and specifically, a locking groove recessed inward in the radial direction, Examples include a locking convex portion and a step portion that bulge outward in the radial direction.

The locking portion is a locking groove that is recessed inward in the radial direction . The curled portion is locked by contacting the tip or the side wall of the locking groove with various angles. Even when a load or impact is applied, deformation of the curled portion can be reliably prevented. Further, the locking groove can be formed relatively easily by pressing toward the inside in the radial direction from the outside of the body portion.
In addition, since the tip of the curled portion is already accommodated in the locking groove, the tip of the curled portion comes into contact with the groove bottom and side wall of the locking groove with a slight deformation, and the curl due to load or impact It becomes possible to suppress the deformation of the portion as small as possible. Furthermore, since the cut surface at the tip of the curled portion cannot be visually recognized from the outside, the appearance of the metal container can be improved.

Here, the groove bottom of the locking groove is formed in a curved shape, and the curvature radius R of the curve formed by the cross section along the axis of the groove bottom is set to 1 with respect to the plate thickness t at the tip of the curled portion. It is preferable to set within the range of 0.0 × t ≦ R ≦ 4.0 × t.
In this case, the radius of curvature R of the groove bottom of the locking groove is R ≧ 1.0 × t with respect to the plate thickness t at the tip of the curled portion, so that the coating formed on the inner surface of the metal container The film layer can be prevented from cracking and the function as a metal container can be secured. In addition, since the radius of curvature R of the groove bottom of the locking groove is R ≦ 4.0 × t, it is possible to securely lock the tip of the curled portion and effectively prevent the curled portion from being deformed. .

Furthermore, it is preferable that the opening angle α in the cross section along the axis of the locking groove is set in a range of 60 ° ≦ α ≦ 120 °.
In this case, since the opening angle α of the locking groove is 60 ° or more, the coating layer formed on the inner surface of the metal container can be prevented from cracking. Further, since the opening angle α of the locking groove is 120 ° or less, the curling portion can be prevented from being deformed by locking the tip of the curling portion with the side wall of the locking groove.

Further, in a cross section along the axis of the locking groove, an intersection angle β between the side wall of the locking groove on the can body side and a plane orthogonal to the axis is within a range of 30 ° ≦ β ≦ 60 °. It is preferable to set to.
In this case, since the intersection angle β between the side wall of the locking groove on the can body side and the plane perpendicular to the axis is 30 ° or more, the coating layer formed on the inner surface of the metal container is prevented from cracking. can do. On the other hand, since the intersecting angle β is 60 ° or less, the curled portion can be prevented from being deformed by locking the tip of the curled portion with the side wall of the locking groove.

According to the present invention, even when a shock or load acts on the curl portion, it is possible to provide a metal container may never curl portion is easily deformed.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
The metal container 10 which is the 1st Embodiment of this invention is shown in FIGS. 1-3. The metal container 10 which is this embodiment is used as a beverage can, for example, and has a trunk portion 11 extending along the axis L as shown in FIG. 1, and one end of the trunk portion 11 (in FIG. 1) An opening 12 is provided at the upper end), and a bottom 13 is provided at the other end (lower end in FIG. 1) of the body portion 11 to form a bottomed cylindrical shape.

  Further, in the present embodiment, the opening portion 12 side portion of the body portion 11 is drawn to have a one-step small diameter, and the shoulder portion 14 that gradually decreases in diameter toward the upper side in the axis L direction, A cylindrical neck portion 15 that extends along the axis L and is connected to the upper end of the shoulder portion 14 is provided. A base portion 16 having a screw portion 19 is provided at an upper portion of the neck portion 15. That is, the metal container 10 according to the present embodiment is a so-called bottle can.

A curled portion 17 is formed at the opening end of the body portion 11, that is, at the upper end of the base portion 16 by folding the opening end of the body portion 11 outward in the radial direction. The leading end surface of the curled portion 17 is a cut surface of a metal plate, and the leading end surface is disposed so as to face the radially inner side of the metal container 10.
An enlarged view of the base part 16 is shown in FIG. A bulging portion 18 that bulges radially outward is formed on the base portion 16 on the lower side in the axis L direction, and the cap is fixed by winding the lower end of the cap around the bulging portion 18. It is set as the structure. Above the bulging portion 18, a screw portion 19 is formed by a screw thread projecting radially outward and a screw valley retreating radially inward.

A locking groove 20 is provided above the screw portion 19, that is, at the opening end portion of the outer peripheral surface of the body portion 11, as a locking portion that can lock the tip 17 </ b> A of the curled portion 17.
The locking groove 20 is connected to the upper end of the threaded portion 19 and has a first side wall portion 21 inclined with respect to the axis L so as to gradually go inward in the radial direction as it goes upward in the axis L direction. And a second side wall portion 22 that is inclined with respect to the axis L so as to gradually go outward in the radial direction as it goes upward in the axis L direction.

  Here, in the present embodiment, the tip 17 </ b> A of the curled portion 17 is accommodated in the locking groove 20. Further, the tip end 17A of the curled portion 17 is inclined so as to gradually go downward in the axial line L direction as it goes inward in the radial direction. It is made to oppose with a slight gap at the crossing part.

The detailed shape of the locking groove 20 will be described with reference to FIG. The groove bottom portion 23 has a concave curved shape that is recessed inward in the radial direction, and the curvature radius R of the curve formed by the cross section along the axis L is 1 with respect to the thickness t of the tip 17A of the curled portion 17. 0.0 × t ≦ R ≦ 4.0 × t, and in this embodiment, R = 2.0 × t.
In addition, the opening angle α in the cross section along the axis L of the locking groove 20, that is, the angle α formed by the first side wall portion 21 and the second side wall portion 22 is set within a range of 60 ° ≦ α ≦ 120 °. In this embodiment, α = 100 °.
Further, in the cross section along the axis L of the locking groove 20, the crossing angle β between the first side wall 21 located on the body 11 side and the plane H orthogonal to the axis L is 30 ° ≦ β ≦ 60 °. In the present embodiment, β = 32 °.

Next, a method for manufacturing the metal container 10 having this configuration will be described. A flow chart of the manufacturing process is shown in FIG.
First, the neck part 15 is formed by drawing the opening 12 side of the metal container 10 having a bottomed cylindrical shape (neck part forming step S1).
Next, a locking groove 20 that is recessed inward in the radial direction is formed by pressing a disk having a convex curved surface on the outer peripheral surface of the upper end of the neck portion 15 (locking groove forming step S2). .
Thereafter, the tip of the neck portion 15 (the opening end of the body portion 11) is rewound outward in the radial direction to form the curled portion 17 (curled portion forming step S3).
Next, the curled portion 17 is pressed inward in the radial direction (compression step S4). At this time, the leading end 17 </ b> A of the curled portion 17 is accommodated in the locking groove 20. Further, the radially outer portion of the curled portion 17 forms a cylindrical surface extending along the axis L by the compression step S4.
Then, the neck portion 15 is sandwiched between the inner peripheral side core and the outer peripheral side outer core to form the screw portion 19 (screw forming step S5).
Thus, the metal container 10 according to the present embodiment is manufactured.

  The metal container 10 configured in this manner is filled with contents such as beverages inside, and then a cap material having a sealing material on the inner surface is put on the cap portion 16, and the bulging portion 18 is capped by the capping device. The lower end of the material is wound and a screw is formed on the peripheral wall portion of the cap material to attach the cap. At this time, a load is applied to the curled portion 17 in the direction of the axis L and inward in the radial direction so that the sealing material is in close contact with the curled portion 17.

  According to the metal container 10 of the present embodiment configured as described above, the locking groove 20 recessed inward in the radial direction is provided at the opening end portion of the outer peripheral surface of the trunk portion 11, so When the curled portion 17 is about to be deformed by an external impact caused by a load or a drop when the cap is attached to the portion 16, the tip 17A of the curled portion 17 is the groove bottom 23 of the locking groove 20 or the first, The second side wall portions 21 and 22 are abutted and locked. Thereby, the movement of the tip 17A of the curled portion 17 is restricted, and deformation of the curled portion 17 can be suppressed.

In the present embodiment, as described above, the tip 17A of the curled portion 17 is engaged with the groove bottom portion 23 of the locking groove 20 or the first and second side wall portions 21 and 22 to be locked. Even when a load or impact is applied from any angle, the deformation of the curled portion 17 can be reliably prevented.
Further, the locking groove 20 that locks the tip end 17A of the curled portion 17 can be formed relatively easily by pressing inward in the radial direction from the outside of the body portion 11.

  Further, in this embodiment, the groove bottom 23 of the locking groove 20 has a concave curved shape that is recessed radially inward, and the curvature radius R of the curve formed by the cross section along the axis L of the groove bottom 23 is The thickness t of the tip 17A of the curled portion 17 is set within a range of 1.0 × t ≦ R ≦ 4.0 × t, more specifically, R = 2.0 × t. As a result, the processing conditions are relatively gentle, and the coating layer formed on the inner surface of the metal container 10 can be prevented from cracking. Deformation can be effectively prevented. In order to achieve such an effect reliably, it is preferable to set the curvature radius R within a range of 2.0 × t ≦ R ≦ 3.0 × t.

  Furthermore, the opening angle α in the cross section along the axis L of the locking groove 20, that is, the angle α formed by the first side wall portion 21 and the second side wall portion 22 is set within a range of 60 ° ≦ α ≦ 120 °. More specifically, since α = 100 °, the processing conditions are relatively gentle, and the coating layer formed on the inner surface of the metal container 10 can be prevented from cracking, and The tip 17A of the curled portion 17 can be locked by being brought into contact with the first and second side wall portions 21 and 22 of the locking groove 20. In order to achieve such an effect reliably, it is preferable to set the opening angle α within a range of 75 ° ≦ α ≦ 105 °.

  Further, in the cross section along the axis L of the locking groove 20, the crossing angle β between the first side wall portion 21 located on the body 11 side and the plane H orthogonal to the axis L is 30 ° ≦ β ≦ 60 °. In this embodiment, β = 32 °, so that the processing conditions are relatively gentle and the coating layer formed on the inner surface of the metal container 10 is prevented from cracking. The tip 17A of the curled portion 17 can be brought into contact with the first and second side wall portions 21 and 22 of the locking groove 20 and locked.

  Further, in the present embodiment, the tip 17A of the curled portion 17 is accommodated in the locking groove 20, so that the tip 17A of the curled portion 17 is slightly deformed so that the groove bottom 23 of the locking groove 20 and the first, The second side wall portions 21 and 22 are brought into contact with and locked, so that the deformation of the curled portion 17 due to a load or an impact can be suppressed as small as possible. Furthermore, since the cut surface of the tip 17A of the curled portion 17 cannot be visually recognized from the outside, the appearance of the metal container 10 can be improved.

  Further, as a method of manufacturing the metal container 10 according to the present embodiment, as shown in the flowchart of FIG. 4, after the locking groove forming step S <b> 2 for forming the locking groove 20, the curled portion 17 is moved radially inward. Since the compression step S <b> 4 for compressing is provided, the tip 17 </ b> A of the curled portion 17 can be accommodated in the locking groove 20. Further, by pressing the curled portion 17 inward in the radial direction, the rigidity of the curled portion 17 in the axis L direction can be improved.

Next, a second embodiment of the present invention will be described with reference to FIG.
In the second embodiment, the shape of the curled portion 47 is different from that of the first embodiment. That is, in the metal container 40 according to the second embodiment, the tip 47A portion of the curled portion 47 is wound into the curled portion 17 so as to gradually go upward in the axis L direction as it goes radially inward. The ridgeline of the front end surface of the curled portion 47 is brought into contact with the intersecting portion between the groove bottom portion 53 of the locking groove 50 and the second side wall portion 52.
In the second embodiment, a resin film is formed on the groove bottom portion 53 and the first and second side wall portions 51 and 52 of the locking groove 50 as anti-slip means.

According to the metal container 40 of the second embodiment, the tip 47A of the curled portion 47 is brought into contact with the intersecting portion between the groove bottom portion 53 of the locking groove 50 and the second side wall portion 52. Even when a load or an impact is applied to the portion 47, the tip 47A of the curled portion 47 does not move, and the deformation of the curled portion 47 can be suppressed as much as possible.
In addition, since the tip surface of the curled portion 47 is wound into the curled portion 47 and is gradually directed upward in the axis L direction as it goes radially inward, the tip surface of the curled portion 47 (metal There is no possibility that the cut surface of the plate is visible from the outside.
Further, since a resin film is formed on the groove bottom portion 53 of the locking groove 50 and the first and second side wall portions 51, 52 as anti-slip means, the tip 47 </ b> A of the curled portion 47 is the groove bottom portion 53 of the locking groove 50. Further, it is possible to prevent the first and second side wall portions 51 and 52 from moving in sliding contact with each other, and the deformation of the curled portion 47 can be reliably suppressed.

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
For example, as a locking part for locking the tip of the curl part, it has been described that a locking groove that is recessed inward in the radial direction is formed on the outer peripheral surface of the body part. It may be a locking projection protruding outward in the direction or a stepped portion having a different protruding height in the radial direction. The shape of the groove is not limited as long as the tip of the curled portion can be locked.

  In addition, although the metal container has been described as a so-called bottle can in which a neck having a small diameter is formed on the opening side of the body part, the present invention is not limited to this, and for example, a so-called wide-mouth container as shown in FIGS. There may be. The metal container 60 shown in FIG. 6 has a screw part 69 formed on the upper part of the body part 61, and a cap that can be opened and closed is attached thereto. The metal container 80 shown in FIG. 7 has a lid attached to a curled portion 87 formed at the end of the opening 82.

  Furthermore, as a manufacturing method of the metal container according to the present embodiment, the flow diagram shown in FIG. 4 has been described as an example. However, the present invention is not limited to this. For example, as shown in the flowchart of FIG. After forming (screw portion forming step S′2), a locking groove and a curled portion may be formed (locking groove forming step S′3, curl portion forming step S′4). If the compression step S′5 is provided after S′3, the end of the curl portion can be brought close to the locking groove (locking portion).

  Moreover, in 2nd Embodiment, although demonstrated as what formed the resin film as a slip prevention means in the groove bottom part of a locking groove, and the 1st, 2nd side wall part, a slip prevention means is limited to a resin film. However, for example, other anti-slip means may be provided such as increasing the surface roughness of the groove bottom and the first and second side walls. Further, as in the first embodiment, anti-slip means may not be provided on the groove bottom portion of the locking groove and the first and second side wall portions.

It is sectional drawing along the axial direction of the metal container which is the 1st Embodiment of this invention. It is an enlarged view of the opening part vicinity of the metal container shown in FIG. It is detail drawing of the locking groove provided in the metal container shown in FIG. It is a flowchart which shows the manufacturing method of the metal container shown in FIG. It is an enlarged view near the opening part of the metal container which is the 2nd Embodiment of this invention. It is sectional drawing along the axial direction of the metal container which is other embodiment of this invention. It is sectional drawing along the axial direction of the metal container which is other embodiment of this invention. It is a flowchart which shows the other manufacturing method of the metal container which is embodiment of this invention.

Explanation of symbols

10, 40, 60, 80 Metal container 11, 41, 61, 81 Trunk part 12, 42, 62, 82 Opening part 17, 47, 67, 87 Curl part 20, 50, 70, 90 Locking groove (locking part) )
21, 51 First side wall (side wall)
22, 52 Second side wall (side wall)
23, 53 Groove bottom (groove bottom)

Claims (4)

A metal container having a bottomed cylindrical shape having a cylindrical body portion extending along an axis, an opening portion provided at one end of the body portion, and a bottom portion provided at the other end,
The opening is formed with a curled portion by folding one end of the body portion radially outward,
The outer peripheral surface of the body portion is provided with a locking portion that locks the tip of the curl portion, and the locking portion is a locking groove that is recessed radially inward,
A metal container, wherein a tip of the curled portion is accommodated in the locking groove . The groove bottom of the locking groove is formed in a curved shape, and the radius of curvature R of the curve formed by the cross section along the axis of the groove bottom is 1. The metal container according to claim 1, wherein the metal container is set within a range of 0 × t ≦ R ≦ 4.0 × t. 3. The metal container according to claim 1 , wherein an opening angle α in a cross section along the axis of the locking groove is set within a range of 60 ° ≦ α ≦ 120 °. In a cross section along the axis of the locking groove, an intersection angle β between the side wall of the locking groove on the can body side and a plane orthogonal to the axis is set within a range of 30 ° ≦ β ≦ 60 °. The metal container according to any one of claims 1 to 3, wherein the metal container is formed.

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