KR100646261B1 - Metal can and manufacturing method of the same - Google Patents

Abstract

A metal can capable of suppressing cracking of a flange by improving a joining structure and a seaming method of a body and a lid, and a manufacturing method of the metal can are provided. A manufacturing method of a metal can comprises the steps of: necking an end of a body portion of the body to form a neck; forming an edge of a lid to form a capping part having an internal space for accommodating the neck; assembling the body and the lid to cover the capping part on the neck; primarily press forming the neck and the capping part to form a first deformed part; and secondly press forming the neck and the capping part at a location distanced from the first deformed part to form a second deformed part. A metal can comprises: a body(10) having a bottom part, a body part and a neck(16); and a lid(20) which is seamed onto the body by having a capping part(22) for covering the neck on an edge, wherein the neck and the capping part a first deformed part(30) and a second deformed part(32) deformed by press forming according to their height directions.

Description

METAL CAN AND MANUFACTURING METHOD THEREOF {METAL CAN AND MANUFACTURING METHOD OF THE SAME}

1A to 1C are schematic diagrams illustrating a necking and flanging molding process of a metal can body according to the prior art.

Figure 2 is a schematic diagram showing the winding process of the metal can body and the lid according to the prior art.

3 is a process flowchart showing a metal can manufacturing method according to an embodiment of the present invention.

4 is a cross-sectional view of the main body and the lid shown to explain the first process and the second process in the metal can manufacturing method according to an embodiment of the present invention.

FIG. 5 is a partially enlarged cross-sectional view of a main body and a lid illustrated to explain a third process in the method of manufacturing a metal can according to an embodiment of the present invention.

FIG. 6 is a partially enlarged cross-sectional view of a main body and a lid illustrated to describe a fourth process in the method of manufacturing a metal can according to an embodiment of the present invention.

FIG. 7 is a partially enlarged cross-sectional view of a main body and a lid illustrated to describe a fifth process in the metal can manufacturing method according to the exemplary embodiment of the present invention.

8 is a partially enlarged cross-sectional view of a metal can according to an embodiment of the present invention.

The present invention relates to a metal can, and more particularly, to a metal can and a method for manufacturing the same, in which the coupling structure of the main body and the lid is improved to suppress the flange crack of the main body.

In general, a metal can used for food and beverage storage is composed of a main body consisting of a bottom part and a body part, and a lid coupled to the body part. The bottom part and the body part are integrally molded as a two-piece can, and the bottom part and the body part are separately manufactured and then combined are called a three piece can. The metal cans are filled with the contents of the body, then sealed by a lid, and released after sterilization or retort as necessary.

Conventional metal cans are pre-necked and flanged at the ends of the body to facilitate winding operations. 1A to 1C are schematic diagrams illustrating a necking and flanging molding process of a main body according to the prior art.

Referring to FIG. 1A, the necking die 11 is composed of a necking die 13 and a knock-out 15. The main body 17 which has completed molding enters the necking die 13 by a conveyer, and necking molding is performed along the curved surface of the necking die 13 as shown in FIG. Subsequently, referring to FIG. 1C, the flanging head 19 is pressed on the main body 17 and rotated. The upper edge of the body 17 is then deformed outward to form the flange 21.

2 is a schematic view showing the winding process of the main body and the lid, and the lid 23 forms the curl portion 25 at the edge facing the flange 21. The usual winding machine consists of a winding roll and a chuck, and the winding roll consists of a primary forming roll and a secondary forming roll. The primary forming roll pushes the curl portion 25 of the lid 23 under the flange 21 of the main body 17 to primaryly form the curl portion 25 and the flange 21, and the secondary forming roll is the primary molding roll. The molded flange 21 and the curled portion 25 are crimped to complete the seal.

In the aforementioned metal can manufacturing process, the flanging process of the main body 17 is classified into stretch-flange deformation which mainly causes tensile deformation. In this case, if a material defect such as a non-metallic inclusion exists in the material of the main body 17 serving as the flange 21 or a mechanical defect exists in the trimming process, a crack occurs. This type of defect is called a flange crack, and since the length of the flange crack is very small, several millimeters or less, it is difficult to detect even a detector.

Therefore, the present invention is to solve the above problems, an object of the present invention is to provide a metal can and a manufacturing method thereof that can suppress the flange crack by improving the coupling structure and the winding method of the main body and the lid.

In order to achieve the above object, the present invention,

Forming a neck by necking the body end of the main body; forming a capping part having an inner space to accommodate the neck by molding the edge of the lid; and assembling the capping part to the neck by assembling the main body and the lid; And forming a first deformable portion by first pressing the neck and the capping part to form a first deformable part, and forming a second deformed portion by pressing the neck and the capping part secondarily at a position spaced apart from the first deformed part. Provide a method.

When the capping part is formed, beads having a convex shape toward the main body may be simultaneously formed inside the capping part.

When the first deformation portion and the second deformation portion are formed, pressure molding may be performed in opposite directions.

More specifically, when forming the first deformation portion, the center of the neck and the capping portion are press-molded in the direction from the outer side of the metal can toward the inside, and when forming the second deformation portion, the first deformation portion is formed under the first deformation portion than the first press forming. Press molding can be performed with a small force.

In addition, the present invention, in order to achieve the above object,

A main body having a bottom portion, a body portion, and a neck, and a lid wound around the body, having a capping portion covering the neck at the rim, wherein the neck and the capping portion are deformed by pressure molding along the height direction thereof; And a metal can having a second deformable portion.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a process flowchart showing a metal can manufacturing method according to an embodiment of the present invention.

Referring to FIG. 3, the metal can manufacturing method includes a first step S1 of forming a neck by necking a body end of a main body, and a second step of forming a capping part having an inner space to accommodate a neck by molding a lid rim. (S2), a third step (S3) of assembling the main body and the lid to cover the capping portion on the neck, a fourth step (S4) of pressing the neck and the capping portion to form the primary winding, and a primary forming portion and a predetermined And a fifth step (S5) of pressing the neck and the capping part at a distance and forming the secondary winding.

4 is a cross-sectional view of the main body and the lid shown for explaining the first step and the second step.

Referring to FIG. 4, the body 10 is formed by integrally molding the bottom part 12 and the body part 14 or by separately manufacturing the bottom part 12 and the body part 14, In the first step (S1), the neck 16 of the end portion of the trunk portion 14 is necked using a conventional necking die (not shown) to form a neck 16 having a narrower width than the trunk portion 14 to a predetermined height. In the present embodiment, the body 10 is not flanged after the necking molding.

In the second step (S2), the edge of the lid 20 facing the neck 16 is press-molded to form a capping part 22 having an internal space for accommodating the neck 16. The capping portion 22 is formed to have a predetermined height corresponding to the neck 16. In the process of forming the capping part 22, the beads 24 may be molded together into the capping part 22. The bead 24 has a convex shape toward the inside of the main body 10 and later serves to increase the coupling force between the neck 16 and the lid 20 in contact with the inner surface of the neck 16.

5, 6 and 7 are partially enlarged cross-sectional views of the main body and the lid shown to explain the third process, the fourth process and the fifth process, respectively.

First, referring to FIG. 5, in the third process S3, the cap 10 is assembled by assembling the cap 10 formed by the main body 10 and the capping part 22 in which the neck 16 is formed. Cover with (16).

Subsequently, referring to FIG. 6, in the fourth step S4, the assembled neck 16 and the capping part 22 are wound by using a primary forming roll (not shown) of the winding machine to cover the main body 10 and the lid. (20) to fasten. In the primary molding, the pressing direction may be a direction from the outer side of the capping portion 22 to the inner side, and the pressing position may be the center of the neck 16 and the capping portion 22 along the height direction of the neck 16. Can be.

In the figure, reference numeral 30 denotes a first deformation portion that is convexly deformed toward the inside of the capping portion 22 by primary molding. Although the winding of the main body 10 and the lid 20 can be completed by the above-mentioned primary molding, the secondary molding is performed because the edge of the lid 20 may not be completely adhered to the neck 16. .

Referring to FIG. 7, in the fifth process S5, the body 10 and the lid 20 are pressed by pressing a position away from the first deformable portion 30 by a predetermined distance using the secondary forming roll (not shown) of the winding machine. Complete the winding molding of). In the secondary molding, the pressing direction is opposite to the pressing direction in the primary molding, and the pressing direction is performed with less force than the primary molding, and the pressing position becomes a lower point toward the main body 10 in the first deforming part 30. Can be. In the drawings, reference numeral 32 denotes a second deformed portion that is concavely deformed toward the inside of the capping portion 22 by secondary molding.

The metal can completed through the above-described process essentially prevents the occurrence of flange cracks by omitting the flanging process, and suppresses product defects due to the flange cracks.

On the other hand, in order to apply the cap fastening method of the metal can described above, it is necessary to optimize the molding depth by the primary forming roll and the secondary forming roll. In other words, if the first deformable portion 30 and the second deformable portion 32 are formed to a too small depth, the winding of the main body 10 and the lid 20 may not be completed, and the contents of the metal can may leak. On the contrary, if the first deformable portion 30 and the second deformable portion 32 are formed at too large a depth, breakage may occur in the winding process.

8 is a partially enlarged cross-sectional view of the completed metal can, in which D ₁ represents the maximum outer diameter of the capping portion 22 after molding, D ₂ represents the outer diameter of the first deformable portion 30, and D ₃ 2 shows the outer diameter of the neck 16 of the deformable portion 32. In this embodiment, the metal can is formed to satisfy the following two conditions at the same time, and as a result, it is possible to ensure excellent sealing of the body 10 and the lid 20 without cracking in the winding process.

In the present invention, the main body 10 may be made of an aluminum alloy plate, a tin plated steel sheet or a resin coated metal plate, and may be applied to both three-piece cans and two-piece cans. The main body 10 may be formed by a joining method, a welding method, a drawing redrawing (DRD) method, a drawing and ironing method (DI), a drawing and thin drawing (DTR) method, and a dial + ironing method. The ironing method may be applied. And the lid 20 may be made of aluminum alloy or steel.

(Example)

The main body 10 was manufactured using a DI plated steel sheet having a thickness of 0.246 mm. The outer diameter of the trunk portion 14 is 53.2 mm. The main body 10 was washed and dried, and two neck moldings were performed to form the neck 16. The lid 20 having the capping portion 22 and the beads 24 was made of aluminum alloy, and the main body 10 and the lid 20 were wound up through the above-described primary molding and secondary molding.

After molding, the maximum outer diameter D ₁ of the capping part 22 is set to 52.08 mm, the outer diameter D ₂ of the first deforming part 30 is set to 48.48 mm, and the neck of the second deforming part 32 is formed. (16) 1200 metal cans were produced by setting the outer diameter D ₃ to 51.20 mm. No cracking occurred in the winding process of the main body 10 and the lid 20, and as a result of evaluating whether the winding part was leaked by compressed air supply, it exceeded the limit internal pressure of 6.3 kg / cm ³ It was confirmed that the contents can be safely preserved.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to

As described above, according to the metal can and the method of manufacturing the same, the flange can be effectively suppressed by omitting the flanging molding on the main body and simply winding the lid on the neck formed by the necking molding.

Claims (9)

Necking the body end of the body to form a neck; Forming a cap of the lid to form a capping part having an inner space for accommodating the neck; Assembling the cap with the main body to cover the capping part with a neck; Forming a first deformation part by first pressure molding the neck and the capping part; And Forming a second deformable part by pressing the neck and the capping part secondarily at a position spaced apart from the first deformable part; Metal can manufacturing method comprising a. The method of claim 1, And simultaneously forming beads having a convex shape toward the main body inside the capping part in the forming of the capping part. The method of claim 1, In the forming of the second deformable portion, the press forming of the second deformable portion may be performed in a direction opposite to the press forming of the first deformable portion. The method of claim 1, And forming the first deformable part by press molding the center of the neck and the capping part in a direction from the outside to the inside of the capping part. The method of claim 4, wherein And forming the second deformable part under the first deformable part by press molding with a force less than that of the first press molding. The method of claim 1, And forming the first deformed portion and forming the second deformed portion to simultaneously satisfy the following conditions.

Here, D ₁ represents the maximum outer diameter of the capping portion after molding, D ₂ represents the outer diameter of the first deformation portion, and D ₃ represents the neck outer diameter of the second deformation portion. A main body having a bottom, a body, and a neck; It includes a cap wound on the main body having a capping portion for covering the neck on the rim, And the neck and the capping part have a first deforming part and a second deforming part deformed by pressure molding along a height direction thereof. The method of claim 7, wherein The first deformable portion and the second deformable portion may be convex toward each other in opposite directions and have different depths. The method of claim 8, And the first deformable portion and the second deformable portion simultaneously satisfy the following conditions.

Here, D ₁ represents the maximum outer diameter of the capping portion, D ₂ represents the outer diameter of the first deformation portion, D ₃ represents the neck outer diameter of the second deformation portion.

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