JP2006122990A - Can-top - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a can-top which reduces a material by making the diameter (cutting diameter) of the can-top small while maintaining its strength and which is also hygienically excellent, in a thin can-top in which an annular groove is formed and in which a chuck wall is provided in continuous contact with the outer circumferential wall of the annular groove. <P>SOLUTION: The can-top 1 is equipped with a center panel 2, an annular groove 5 having an inner circumferential wall 6 which is brought into continuous contact with the outer circumferential edge 2a of the center panel 2 and falls from that edge 2a and having an outer circumferential wall 8 which rises via a bottom 7 at the lower end of the inner circumferential wall 6, and a chuck wall 10 which extends, while expanding the diameter, upward in the can axis via a bending part 9 situated at the upper part of the outer circumferential wall 8. The can-top is characterized in that, when a plane passing through and along the can axis ○ is regarded as a first plane, at least one of the radiuses of curvature R2, R3 of a recessed curved face is 0-0.5 mm, in the bottom 7 of the inner and outer circumferential walls 6, 8 in the cross section by the first plane. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a can lid which is wound around a can body opening as an end plate of a can container and is fixed.

  Conventionally, cans, such as beverage cans, which are formed by winding a can lid on the can body opening, have a strength against a so-called buckling in which the center panel of the can lid bulges and deforms outward due to can internal pressure or impact. In order to ensure this, it is common practice to form an annular groove having a concave shape on the lower side (inside the can) connected to the outer peripheral edge of the center panel.

  On the other hand, when the contents are sparkling beverages such as carbonated drinks or beer, or in so-called positive pressure cans where the internal pressure of the can is increased by dropping liquid nitrogen when filling the contents, the can shape is maintained by the internal pressure of the can. For this reason, the thickness of the can body is reduced for the purpose of reducing the cost by reducing the material, and the same thickness reduction is achieved for the can lid.

In parallel with the thinning, in order to reduce the material used by reducing the diameter (cutting diamond) of the can lid material while maintaining the strength of the can lid, it is connected to the outer peripheral wall of the annular groove, On the other hand, a technique has been disclosed in which a chuck wall that expands at a larger angle than the outer peripheral wall is provided, and the chuck wall shape, the depth of the annular groove, the shape of the annular groove bottom, and the like are improved (see, for example, Patent Document 1). ).
JP 2002-178072 A

  However, in a can lid provided with an annular groove as described above, the buckling strength generally decreases when the center panel diameter is increased, so the position of the annular groove is moved radially inward and the distance from the winding portion As a result, the score defining the opening for ingesting the contents from the inside of the can approaches the center of the center panel, and the opening becomes far from the outer periphery of the can, making it difficult to drink the contents. At the same time, the amount of the contents retained in the annular groove during drinking increased, and there was a problem in terms of hygiene such as drinking of the retained contents, scattering of the contents, and spillage.

  The present invention has been made in consideration of such circumstances, and in a thin can lid provided with a chuck wall formed with an annular groove and connected to the outer peripheral wall portion of the annular groove, the strength of the can lid The object is to reduce the material by reducing the diameter (cutting diamond) of the can lid material while maintaining the above, and to provide a sanitary superior can lid.

In order to solve the above-described problem, the can lid according to claim 1 includes a disc-shaped center panel, an inner peripheral wall portion that is connected to the outer peripheral edge of the center panel and rises from the outer peripheral edge, and the An annular groove having an outer peripheral wall portion that rises through the bottom at the lower end of the inner peripheral wall portion; a chuck wall that extends while expanding the diameter upward via a bent portion located at an upper portion of the outer peripheral wall portion; and a chuck And a seam panel extending from the upper end of the wall, and a can lid wound around the can body, and when the plane passing through the can axis and along the can axis is the first plane,
In the cross section of the first plane, at least one of the curvature radii of the concave curved surface at the inner peripheral wall portion and the bottom portion of the outer peripheral wall portion is 0 mm or more and 0.5 mm or less.

  According to the first aspect of the present invention, at least one of the curvature radii of the concave curved surface at the inner peripheral wall portion and the bottom portion of the outer peripheral wall portion in the cross section is formed to be 0 mm or more and 0.5 mm or less, and the annular groove is the annular groove. Since the taper is sharpened toward the bottom, the groove width formed by the material having the same width in the radial direction is parallel to the plane orthogonal to the can axis and the can axis is compared with the U-shaped annular groove having the same width. The cross-sectional secondary moment and section modulus of the annular groove having a neutral line passing therethrough can be increased, and the strength of the annular groove with respect to the bending moment corresponding to the cross-sectional secondary moment and section modulus can be increased.

  The invention according to claim 2 is the can lid according to claim 1, wherein the annular groove is formed by pressing at least one of radially outward with respect to the inner peripheral wall and radially inward with respect to the outer peripheral wall. This is characterized in that the groove width of the annular groove is reduced.

  According to the invention of claim 2, since at least one of the inner peripheral wall portion and the outer peripheral wall portion constituting the annular groove is press-molded with a force toward the center direction of the annular groove, a normal press in the axial direction is performed. Compared to the case of molding, the R shape of the annular groove bottom and the groove width of the annular groove can be reduced.

  The invention according to claim 3 is the can lid according to claim 1 or 2, wherein the plane formed by the bottom surface of the can lid at the bottom of the annular groove is the second plane, The distance in the can axis direction from the intersection in the bent portion formed by extending the outer peripheral wall portion and the chuck wall to the second plane is greater than the distance in the can axis direction from the center panel to the second plane. It is characterized by being.

  According to the can lid of the invention according to claim 3, since the annular groove is sharpened toward the bottom of the annular groove, and the annular groove has sufficient bending strength in the extending direction, the annular groove that supports the center panel is provided. Even if the inner peripheral wall portion of the groove is lowered and the material of the can lid material is reduced, the bending strength is ensured.

  The invention according to claim 4 is the can lid according to claim 3, wherein a distance in the can axis direction from the second plane to the center panel in the cross section is 1.10 mm or more and 1.98 mm or less. Features.

  In the can lid according to claim 3, it is preferable that the distance in the can axial direction from the second plane to the center panel is 1.10 mm or more in terms of the can internal pressure and the buckling strength, In order to reduce the amount of the beverage staying in the annular groove, it is preferable to set it to 1.98 mm or less.

The invention according to claim 5 is the can lid according to claim 3 or claim 4,
A can axial direction distance from the second plane to the intersection in the cross section is 1.10 mm or more and 2.18 mm or less.

  In the can lid according to claim 3 or 4, the can axial direction distance from the second plane to the center panel is preferably 1.10 mm or more in terms of can internal pressure and buckling strength. In order to reduce the amount of material and to reduce the amount of beverage remaining in the annular groove, 2.18 mm or less is preferable.

  The invention according to claim 6 is the can lid according to any one of claims 1 to 5, wherein the winding start point of the upper end of the chuck wall in the winding portion of the can lid wound around the can body is The radial distance in the cross section to the outer periphery of the center panel is 0.7 mm or more and 7.0 mm or less.

  According to the invention which concerns on Claim 6, radial direction distance in the cross section by the 1st plane from the winding start point of the winding part of the can lid wound around the can main body to the outer periphery of a center panel is 0.7 mm or more 7 0.0 mm or less, and the distance from the outer periphery of the can to the outer periphery of the center panel is small, so that the score is closer to the outer periphery of the can and the opening is positioned so that it overlaps the mouth, making it easier to ingest the contents of the can And can reduce swallowing.

  The invention according to claim 7 is the can lid according to any one of claims 1 to 6, characterized in that an angle between the chuck wall and the can axis is greater than 30 ° and not more than 60 °. To do.

  According to the invention which concerns on Claim 7, the material of a can lid raw material is reduced, maintaining the intensity | strength with respect to a can internal pressure and a buckling. In order to reduce the material, it is preferable that the angle formed between the chuck wall and the can shaft is larger than 30 °. In order to maintain the strength, the angle formed between the chuck wall and the can shaft is 60 ° or less. Is preferable.

  The invention according to claim 8 is the can lid according to any one of claims 1 to 7, wherein an angle formed by the outer peripheral wall portion of the annular groove and the can shaft is 5 ° or more and 18 ° or less. It is characterized by.

  According to the invention which concerns on Claim 8, the material of a can lid raw material is reduced, maintaining the intensity | strength with respect to a can internal pressure and a buckling. For reducing the material, it is preferable that the angle formed between the outer peripheral wall portion and the can shaft is 5 ° or more. In order to maintain the strength, the angle formed between the outer peripheral wall portion and the can shaft is set to 18 °. It is preferable to set it to 0 ° or less.

The invention according to a ninth aspect is the can lid according to any one of the first to eighth aspects, wherein the seaming panel is wound around the can body and the tightening portion is formed. wherein said outer peripheral edge of the center panel, a line connecting the seaming origin of the seaming portion, that area of the region defined by the can lid is 1.6 mm ² or more 8.0 mm ² or less at It is characterized by.

According to the ninth aspect of the present invention, the area defined by the can lid and the straight line connecting the outer peripheral edge of the center panel and the winding start point of the tightening portion in the cross section of the first plane is 1. since that is .6Mm ² or 8.0 mm ² or less, it is easily and becomes and drinking returning less ingestion of content, less the amount of the contents to be retained in the annular groove.

  According to the present invention, an annular groove is formed, a chuck wall that is connected to the outer peripheral wall portion of the annular groove and expands at a larger angle than the outer peripheral wall portion, and is provided with a hygienic good can lid. The material used can be reduced and provided at low cost without reducing the strength.

Hereinafter, embodiments of the can lid of the present invention will be described with reference to FIGS. 1, 2, and 3.
FIG. 1 shows a can lid 1 before being tightened according to an embodiment of the present invention, which is cut by a first plane (not shown) passing through the axis O of the can lid 1 and along the axis. It is a longitudinal cross-sectional view in a cross section. 2 is a longitudinal sectional view showing details of a region from the annular groove 5 of the can lid 1 shown in FIG. 1 to the seaming panel 20, and FIG. 3 shows the can lid 1 shown in FIG. FIG.
FIG. 1 shows a can lid 1 having a thickness t = 0.215 mm of an aluminum alloy (5182-H39), an outer diameter D1 = 59.40 mm, and an outer diameter D2 = 53.78 mm in a double-tightened state. The disc-shaped center panel 2, the annular groove 5, the chuck wall 10, and the seaming panel 20 are provided.

Further, as shown in FIG. 2, the annular groove 5 is connected to the outer peripheral edge 2 a of the center panel 2, and is located at the inner peripheral wall portion 6 that rises from the outer peripheral edge 2 a via the R shape R <b> 1 and at the lower end of the annular groove 5. In addition, a bottom part 7 connected via the inner peripheral wall part 6 and R2 and an outer peripheral wall part 8 connected via the bottom part 7 and R3 and rising in the direction of the can lid axis O while expanding the diameter are provided.
The outer peripheral edge 2a of the center panel 2 substantially coincides with the starting point on the R1 center panel 2.

Here, R1 is a recess formed between the outer peripheral edge 2a and the inner peripheral wall 6 on the lower surface of the can lid 1 and having a radius of curvature of 0.1 mm or more and 0.5 mm or less in the cross section of the first plane. It is a curved surface, and in this embodiment, R1 = 0.353 mm.
R2 is formed between the inner peripheral wall portion 6 and the bottom portion 7 on the upper surface of the can lid 1 of the annular groove 5, and has a radius of curvature of 0 mm or more and 0.5 mm or less in a cross section by the first plane. It is a curved surface, and in this embodiment, R2 = 0.143 mm.
R3 is formed between the bottom portion 7 and the outer peripheral wall portion 8 on the upper surface of the can lid 1 of the annular groove 5, and has a radius of curvature of 0 mm or more and 0.5 mm or less in a cross section by the first plane. It is a curved surface, and in this embodiment, R3 = 0.153 mm.
In R2 and R3, the case where the radius of curvature is 0 mm indicates a case where the connecting portion at the bottom portion 7 of the inner peripheral wall portion 6 or the outer peripheral wall portion 8 becomes a corner portion and is substantially free of R due to reform molding or the like.

A bent portion 9 is provided at a connecting portion between the upper end of the outer peripheral wall portion 8 and the chuck wall 10, and a geometric position thereof is defined by an intersection 9 a of an imaginary line obtained by extending the outer peripheral wall portion 8 and the chuck wall 10. Is done.
When a plane (not shown) formed by the can lid lower surface 7a of the bottom 7 of the annular groove 5 is a second plane, and the second plane is a reference for the height of the can lid 1 in the can axis direction, the center panel The distance H2 from 2 to the reference and the distance H3 from the intersection 9a to the reference are set as H3 ≧ H2.

The distance H2 from the center panel 2 to the reference is preferably 1.10 mm or more and 1.98 mm or less, and the distance H3 from the intersection 9a to the reference is preferably a numerical value of 1.10 mm or more and 2.18 mm or less. In this case, H2 = 1.33 mm and H3 = 2.0 mm.
Further, a seaming panel 20 is connected to the upper end of the chuck wall 10 and, as shown in FIG. 3, the seaming panel 20 is double-wrapped around the can body 15 so as to close the can body opening 15a. It has become.

Further, the product height H1 after winding of the can lid 1 defined by the distance from the reference of the height in the can axis direction to the top of the winding portion 21 of the can lid 1 after winding is 6.23 mm. , H1 is preferably 4.0 mm or more and 8.0 mm or less.
The height of the can lid 1 before tightening is H4 = 6.50 mm, and H4 is preferably 4.0 mm or greater and 8.0 mm or less.

The angle A1 formed by the outer peripheral wall portion 8 of the annular groove 5 and the can shaft is 5 ° or more and 18 ° or less, and is 15 ° in this embodiment.
Further, the angle A2 formed by the chuck wall 10 and the can axis is set to be larger than 30 ° and not larger than 60 °, and is 39 ° in this embodiment.
The radial distance D3 = 2.93 mm from the winding starting point 21a at the upper end of the chuck wall 10 to the outer peripheral edge 2a of the center panel 2 in the can lid 1 in a state of being wound around the can body 15 is 0.7 mm or more. A numerical value of 0.0 mm or less is set.

Further, in a state where the seaming panel 10 is wound around the can body 15 and the tightening portion 21 is formed, the outer peripheral edge 2a of the center panel 2 and the tightening are cut in a cross section passing through the can shaft O and in the can shaft direction. The straight line L connecting the winding start point 21a of the portion 21 and the can lid 1 extending from the outer peripheral edge 2a of the can lid 1 to the winding start point 21a of the seaming panel 10 via the annular groove 5 and the chuck wall 10. area made the region 23 is 4.5 mm ^2, is preferably 1.6 mm ² or more 8.0 mm ² or less.

Next, a method for manufacturing the can lid 1 will be described.
First, the aluminum alloy plate used as a material is punched into a disc-shaped blank and formed into a can lid material by pressing. The outer peripheral edge of the can lid material thus punched is a rotary molding machine (rotary curler). Or curling with a press molding machine. At this time, a chuck wall 10 and a seaming panel 20 as shown in FIG. 1 are formed on the outer peripheral edge of the can lid material.

  Before or after the curling molding, the inner circumferential wall portion 6 and the outer circumferential wall portion 8 of the annular groove 5 are reformed. Reform molding is a direction in which the groove width of the annular groove 5 is reduced by pressing, that is, radially outward pressing in the case of the inner peripheral wall 6, and radial inward pressing in the case of the outer peripheral wall 8. Alternatively, press molding is performed on either side.

  Next, after forming the seaming panel 20 in this manner, formation of a score (not shown), formation of a drinking mouth (not shown), and attachment of a pull tab (not shown) by a known can lid forming method. Etc., and the final can lid 1 is formed.

  According to the can lid of the above-described embodiment, the radial distance D3 from the winding start point of the upper end of the chuck wall to the outer periphery of the center panel is 2.93 mm in a state where the can lid is wound around the can body. Since the distance from the winding starting point to the center panel outer peripheral edge 2a is small, the contents can be easily ingested, and the amount of rejuvenation returning from the mouth to the opening when the drinking is interrupted can be reduced.

  Moreover, in the cross section by the 1st plane, the curvature radius R2 of the concave curved surface formed in the lower end of the inner peripheral wall part 5 is 0.143 mm, and the curvature radius R3 of the concave curved surface formed in the lower end of the outer peripheral wall part is 0.153 mm. Therefore, a neutral line that is parallel to a plane perpendicular to the can axis O and passes through the can axis O, as compared to a U-shaped annular groove having the same groove width formed by a material having the same width in the radial direction. It is possible to increase the cross-sectional secondary moment and the section modulus of the annular groove having, and to increase the strength of the annular groove 5 with respect to the bending moment corresponding thereto.

  Further, the can axis direction height H2 to the center panel 2 with respect to the second plane is set to 1.33 mm, the can axis direction height H3 to the intersection 9a of the bent portion 9 is set to 2.0 mm, and H3 Since> H2, material reduction is realized without lowering the bending strength of the can lid 1.

Further, since the angle between the chuck wall 10 and the can axis is 39 ° and the angle between the outer peripheral wall portion 8 and the can axis is 15 °, the material of the can lid material is maintained while maintaining the strength against the can internal pressure and the buckling. Is reduced.
In the case of the above-described embodiment (202 diameter size, can diameter 53.975 mm), material reduction of about 4% is realized as a whole.

Further, since the area of the region 23 defined by the straight line L connecting the outer peripheral edge 8 of the center panel 2 and the winding starting point 21a of the winding portion 21 and the can lid 1 in the cross section is as small as 4.5 mm ² , the contents Can be easily ingested, and can reduce the amount of replenishment and the contents retained in the annular groove 5, which is advantageous in terms of hygiene.

  According to the above-described embodiment, since reforming is performed on at least one of the inner peripheral wall 6 and the outer peripheral wall 8 toward the center of the annular groove 5, the annular groove 5 is formed in comparison with normal press molding. It is possible to reduce the concave curved surfaces R2 and R3 of the bottom portion 7 and sharpen the annular groove 5 toward the bottom portion 7 to obtain high strength.

  The outer diameter, height, and plate thickness of the can lid 1 can be selected without being limited to the above embodiment, and the material and material of the can lid 1 are used in the can manufacturing field. For example, in addition to aluminum plates and 3004, 5182 and other aluminum alloy plates, tin-plated steel sheets that have been subjected to post-tin plating treatment, nickel-plated steel plates, tin and nickel were plated and then subjected to chemical conversion treatment in the order of tin and nickel. A surface-treated steel plate such as a tin / nickel-plated steel plate or a chromium / chromate-treated steel plate to which metallic chromium is attached may be used. It is also possible to use a plate material on which a film is laminated.

In addition, this invention is not limited only to the said embodiment, For example, regarding the plate | board thickness of the can lid 1, an outer diameter, the center panel 2, the component of the annular groove 5, the chuck wall 10, and the seaming panel 20 Can be freely selected within a range not departing from the gist of the present invention.
Further, in the above embodiment, the case where both R2 and R3 are suitable numerical values has been described. However, only one of them may adopt a preferable value, and R2 and R3 are connected for R2 and R3. It may be directly connected.
Further, the shape of the seaming panel 20 can be freely selected, and the connection portion with the chuck wall 10 may be bent.

  Further, in reform molding, it is possible to perform pressing by roller processing, a die, or the like, not limited to pressing from the radial direction of the can lid 1, but pressing in the direction of the can axis O to form the annular groove 5 with its groove width. Alternatively, it may be molded by being pushed into a mold having a narrower gap.

It is a longitudinal cross-sectional view which shows the outline of the can lid before winding fastening which concerns on embodiment of this invention. It is the longitudinal cross-sectional view which showed the detail of the area | region from the annular groove of a can lid to a seaming panel. It is the longitudinal cross-sectional view which showed the detail of the can lid in the state wound around the can main body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Can lid 2 Center panel 5 Annular groove 6 Inner peripheral wall part 7 Bottom part 8 Outer peripheral wall part 10 Chuck wall 15 Can main body 20 Seaming panel 21 Winding part 21a Winding start point 23 Area | region O Can axis

Claims (9)

A disc-shaped center panel, an annular groove having an inner peripheral wall portion connected to the outer peripheral edge of the center panel and rising from the outer peripheral edge, and an outer peripheral wall portion rising from the bottom at the lower end of the inner peripheral wall portion; A can that is wound around a can body, comprising: a chuck wall extending upwardly through a bent portion positioned at an upper portion of the outer peripheral wall portion; and a seaming panel extending from an upper end of the chuck wall. A lid,
When the plane passing through the can axis and along the can axis is the first plane,
The can lid characterized in that at least one of the curvature radii of the concave curved surface at the inner peripheral wall portion and the bottom portion of the outer peripheral wall portion is 0 mm or more and 0.5 mm or less in a cross section by the first plane. The can lid according to claim 1,
The can groove characterized in that the annular groove has a groove width reduced by pressing at least one of radially outward with respect to the inner peripheral wall and radially inward with respect to the outer peripheral wall. . The can lid according to claim 1 or claim 2,
When the plane formed by the bottom surface of the can lid at the bottom of the annular groove is the second plane,
In the cross section, a can axial direction distance from an intersection of the bent portion formed by extending the outer peripheral wall portion and the chuck wall to the second plane is from the center panel to the second plane. A can lid characterized by having a distance in the can axis direction or more. The can lid according to claim 3,
The can lid, wherein a distance in the can axis direction from the second plane to the center panel in the cross section is 1.10 mm or more and 1.98 mm or less. The can lid according to claim 3 or claim 4,
The can lid has a can axial direction distance from the second plane to the intersection in the cross section of 1.10 mm or more and 2.18 mm or less. The can lid according to any one of claims 1 to 5,
The radial distance in the cross section from the winding starting point of the upper end of the chuck wall to the outer peripheral edge of the center panel in the tightening portion of the can lid wound on the can body is 0.7 mm or more and 7.0 mm or less. Can lid. The can lid according to any one of claims 1 to 6,
The can lid characterized in that an angle between the chuck wall and the can axis is greater than 30 ° and 60 ° or less. The can lid according to any one of claims 1 to 7,
The can lid characterized in that an angle formed by an outer peripheral wall portion of the annular groove and a can axis is 5 ° or more and 18 ° or less. The can lid according to any one of claims 1 to 8,
A straight line connecting the outer peripheral edge of the center panel and the winding starting point of the winding part in the cross section in a state where the seaming panel is wound around the can body and a fastening part is formed; can lid, wherein the area of the area defined is 1.6 mm ² or more 8.0 mm ² or less by the.

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