JP2001213416A - Metal can with screw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal can with a screw for improving the strength of the upper ends of a mouth section and a shoulder section. SOLUTION: The metal can with the screw is provided with at least one or more smooth recesses 4 bending to the inside and at least one or more smooth protrusions 5 bending to the outside formed on the periphery of a tapered upper end 3a expanded gradually from the lower end 2a of a screw section of the mouth section in the radius direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a threaded metal can with improved strength at the mouth and the upper end of a shoulder having a threaded portion.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 10, a metal can with a screw made from a metal material such as aluminum by drawing, drawing and ironing or impact molding has a screw portion formed on the outer periphery of the mouth of the metal can. Then, the cap was screwed on and the mouth was sealed. FIG. 10 is a sectional view showing a conventional screwed metal can. Reference numeral 50 denotes a can main body. The can main body 50 includes a curl portion 51, a mouth portion 52 having a screw portion, a tapered shoulder portion 53, a body portion 54, and a bottom portion 55 from above. And the female screw of the cap 56,
The male screw of the mouth 52 was screwed together, and the mouth 52 of the can body 50 was closed. In the conventional can main body 50, the shoulder 53 is formed linearly up to the shoulder upper end 53a, and is continuous from the shoulder upper end 53a to the screw lower end 52a.

In the conventional can main body 60 shown in FIG. 12, a plurality of projections 6 are formed on the entire shoulder 61 at substantially regular intervals.
Two (three in the drawing) threaded metal cans are flowing to the market.

[0004]

However, in the can body 50 shown in FIG. 10, as shown in FIG.
The lower end 52a of the screw portion and the upper end 53a (region W) of the shoulder 53 have radial and axial pressing forces (pressures P and Q).
And the area W was crushed or buckled. Further, in the can body 60 shown in FIG.
The purpose of forming the plurality of convex portions 62 on the whole is mainly to achieve a design effect of a metal can with a screw, and also to prevent wrinkles from being generated in the shoulder portion 61 in a necking process as a manufacturing process. Is formed. Therefore, it was not intended to improve the strength at the mouth and the upper end of the shoulder.

The present invention has been made in view of such a conventional problem.
The object of the present invention is to provide a threaded metal can that aims to improve the strength in the radial direction and the axial direction of the shoulder upper end 53a (region W) of the shoulder 53.

[0006]

Means for Solving the Problems In order to solve this problem, means corresponding to the first aspect of the present invention is made of a metal material by drawing, drawing and ironing or impact molding, and the can body is made of a screw. In the metal can with a mouth portion having a portion, a tapered shoulder, a body and a bottom portion, which can be screwed together with a cap to maintain high sealing performance,
From the threaded lower end of the mouth, around the upper end of the tapered shoulder that expands in the radial direction, at least one or more inwardly smoothly curved concave portions or at least one or more outwardly smoothly curved convex portions were formed. Things.

In order to solve this problem, a means corresponding to the second aspect of the present invention is a metal part formed by drawing, drawing and ironing or impact molding, and a can body having a screw part, A metal can with a tapered shoulder, a torso and a bottom that can be screwed into a cap to maintain high sealing performance. At least one or more inwardly curved concave portions and at least one or more outwardly curved convex portions are formed around the upper end of the shoulder portion.

[0008]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 to 3 show a first embodiment of the present invention.
It is a drawing showing an embodiment. The feature of the first embodiment is that a concave portion 4 that smoothly curves inward is formed at a portion (region A) of a shoulder upper end 3a of a shoulder portion 3 that continues downward from a screw lower end 2a of a mouth portion 2. Then, a convex portion 5 that smoothly curves outward is formed continuously below the convex portion. And the lower part of the convex part 5 is linearly continuous.

FIG. 3 shows a region A of the first embodiment,
It is sectional drawing expanded further. Lower end 2a of screw part of mouth 2
The radius of curvature of the concave portion 4 that continues downward from R is 0.5 to 5.
mm, and specifically, it is preferable that R = about 3 mm. Next, the degree of curvature of the smooth convex portion 5 continuing from the concave portion 4 exhibits an inclination of θ = 35 ° to 60 ° with respect to the vertical direction, and specifically, preferably θ = 45 °.

FIG. 4 is a drawing showing a second embodiment of the present invention. The feature of the second embodiment is that a single smooth concave portion 6 that curves inward is formed at a portion (region B) of the shoulder upper end 3a of the shoulder 3 that is continuous from the screw lower end 2a. The radius of curvature of the concave portion 6 is preferably substantially the same as that of the concave portion 4 of the first embodiment.

FIG. 5 is a drawing showing a third embodiment of the present invention. The feature of the third embodiment is that a single smooth convex portion 7 that curves outwardly is formed at a portion (region C) of the shoulder upper end 3a of the shoulder 3 that is continuous from the screw lower end 2a. . It is preferable that the degree of curvature of the convex portion 7 is the same as that of the convex portion 5 of the first embodiment.

FIG. 6 is a drawing showing a fourth embodiment of the present invention. The feature of the fourth embodiment is that a smooth concave portion 8 that curves inward is formed at a portion (region D) of the shoulder upper end 3a of the shoulder portion 3 that is continuous from the screw lower end 2a, A smooth convex portion 9 is formed on the outside, and a smooth concave portion 10 that curves inward is formed continuously. That is, two concave portions 8 and 10 and one convex portion 9 are formed in the region D. In another embodiment, for example, two concave portions and two convex portions may be mixedly formed (not shown).

Next, the operation of the present invention will be described.
Since the regions A, B, C, and D in the first to fourth embodiments according to the present invention are subjected to bending to form concave portions and / or convex portions, the regions A, B, C, and D are respectively formed in the radial direction and the axial direction. Of the pressing force P and Q improved. The radius of curvature R and the inclination angle θ of the concave portion and / or the convex portion can be increased. However, when it is increased, there is a disadvantage in that although it becomes stronger with respect to the pressing force P in the radial direction, it becomes weaker with respect to the pressing force Q in the axial direction. Therefore, in order to improve the strength of both the pressing forces P and Q, the radius of curvature R of the concave portion described above is required.
It is preferable that the inclination angle is about 0.5 to 5 mm and the inclination angle θ is about 35 ° to 60 °.

[0014]

Next, the results of a strength test of the mouth and the upper end of the shoulder of the threaded metal can according to the first embodiment of the present invention are shown below. FIG. 7 is a view showing a crush test of the beat portion pressing the beat portion 2b of the mouth portion 2 from above with the pressing force F1, FIG.
FIG. 9 is a drawing showing a crush test of a screw portion, which presses the mouth portion 2 from above with a pressing force F2, and FIG. 9 shows a buckling strength test in which the upper end of the mouth portion 2 is pressed with a pressing force F3 from above. It is a drawing. (Test conditions) Can outer diameter: 66 mmφ, can height: 166 mm, mouth outer diameter;
37.8mmφ, wall thickness of screw part and beat part; 0.32
mm, thickness of lower end of shoulder; 0.2 mm, thickness of can body;
15mm

[Table 1] According to the above test results, the metal can with screw according to the present invention,
It was found that the crush strength of the beat portion was improved by 47.8%, the crush strength of the screw portion was improved by 3.6%, and the buckling strength of the shoulder portion was improved by 14.2%.

[0015]

As described above, according to the present invention, the strength of the mouth portion of the threaded metal can, particularly the region from the lower end of the screw portion to the upper end of the shoulder portion, can be improved.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing the mouth and the upper end of the shoulder according to the first embodiment of the present invention.

FIG. 3 is an enlarged sectional view showing a region A according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a mouth and an upper end of a shoulder according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing a mouth and a shoulder upper end according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing the mouth and the upper end of a shoulder according to a fourth embodiment of the present invention.

FIG. 7 is a view showing a crushing strength test of a beat portion of the threaded metal can according to the present invention.

FIG. 8 is a view showing a crushing strength test of a screw portion of the metal can with a screw according to the present invention.

FIG. 9 is a drawing showing a buckling strength test of the shoulder of the metal can with screw according to the present invention.

FIG. 10 is a cross-sectional view showing a conventional screwed metal can.

FIG. 11 is a cross-sectional view showing a mouth and a shoulder upper end of a conventional screwed metal can.

FIG. 12 is a front view of a conventional threaded metal can having a shoulder formed around a shoulder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Can main body 2 Mouth 2a Screw lower end 3 Shoulder 3a Shoulder upper end 4 6 10 Concave part 5 7 9 Convex part

Claims (2)

[Claims] 1. A can body made of a metal material by drawing, drawing and ironing or impact molding, and a can main body comprising a mouth having a threaded portion, a tapered shoulder, a body and a bottom, and screwing the cap. In a threaded metal can that can retain high sealing performance, from the threaded lower end of the mouth, around the upper end of the tapered shoulder that expands in the radial direction, at least one or more concave portions that smoothly curve inward, or at least A metal can with a screw, wherein a smoothly curved convex portion is formed on one or more outer sides. 2. A can body made of a metal material by drawing, drawing and ironing or impact molding, and the can body is composed of a mouth having a threaded portion, a tapered shoulder, a body and a bottom, and the cap is screwed together. In a screwed metal can that can maintain high sealing performance, from the lower end of the screw portion of the mouth, around the upper end of the tapered shoulder gradually expanding in the radial direction, at least one or more inwardly concave recesses smoothly curved, And a metal can with a screw, wherein at least one or more outwardly curved convex portions are formed.