This is the U.S. National Phase Application under 35 U.S.C. §371 of International Patent Application No. PCT/JP2008/061887 filed Jul. 1, 2008, which claims the benefit of Japanese Patent Application No. 2007-177701 filed Jul. 5, 2007, both of which are incorporated by reference herein. The International Application was published in Japanese on Jan. 8, 2009 as WO 2009/005050 A1 under PCT Article 21(2).
The present invention relates to a can end including an easy-open mechanism for sealing a can container, more particularly to a can end suitable to a beverage can container, a can end manufacturing method, and a beverage product using the same.
In the can container typified by a beverage can filled with liquid contents, the can end including a pull-tab that easily open the can is frequently used as the easy-open mechanism.
In the easy-open can end, at the beginning of a can opening operation, it is typical to insert a finger into a gap between the panel 3 and the tab tail 15 of the pull-tab 7 to pull up the pull-tab 7. At the beginning of the can opening operation, it is typical that the pull-tab 7 be pulled up with a large force in order to initially rupture the score 17. Therefore, it is preferable to improve ease of catching of the pull-tab 7 with a finger (hereinafter also referred to as “finger catching property (finger access)”) in order to enhance a can opening property. Conventionally, as illustrated in
That is, the method in which projection is provided in an upper surface of the panel 3, which is in contact with a lower surface of the pull-tab 7, and the method for previously bending the pull-tab 7 are described as the method for uplifting the tab tail 15 from the panel 3 only by a necessary amount in order to spread a gap between the tab tail 15 of the pull-tab 7 and the panel 3 to easily catch the tab tail 15 with the finger (for example, see Japanese Utility Model Publication No. 8-6746). There has also been proposed a method for easily catching the tab tail 15 with the finger by previously providing the a low-strength portion in an outer rim 11 (outside portion of a U-shape notch portion 9 of the pull-tab) of the pull-tab 7 such that the pull-tab 7 is bent by a predetermined amount with a small force to lift the tab tail 15 at the beginning of the can opening operation (for example, see Japanese Utility Model Publication Laid-Open No. 3-111939).
However, when the tab tail of the pull-tab is largely uplifted from the panel 3 in order to ensure the gap enough to catch the tab tail with the finger, the uplifted tab tail comes into contact with the backside (inner surface side of the can) of the panel of the upwardly stacked can end in conveying the stacked can ends or retaining the can end during a process for manufacturing the can end or a process for seaming the can container. Therefore, unfortunately the can ends interfere with each other to damage a film of paint in the backside of the panel, or a gap is generated in the stack of the can ends to degrade the stacking property, which results in a conveyance defect. It is difficult to sufficiently improve the finger catching property (hereinafter the property in which the pull-tabs of the can ends are stably stacked without coming into contact with the upper-side can end in stacking the can ends is referred to as “stacking property of can end”). On the other hand, for the finger catching property improving method in which the pull-tab is bent in opening the can, it is difficult to bend the pull-tab by the predetermined amount, and it is also difficult to ensure the strength necessary for the pull-tab.
An aspect of the present invention is to improve the finger catching property of the pull-tab in the easy-open can end. Specifically, an aspect of the present invention is to provide the easy-open can end in which the tab tail of the pull-tab is sufficiently uplifted from the can end to improve the finger catching property when the can is used as the can container after the can end is seamed while the strength of the pull-tab is maintained without degrading the stacking property of the can end. Another aspect of the present invention is to provide a method for being able to simply mass-manufacture the easy-open can end. Still another aspect of the present invention is to provide an easily-opened beverage product in which the can container sealed by the easy-open can end is used.
As illustrated in
The center of the panel of the can end is recessed to incline the panel, and the pull-tab is bent by pressing-down forming to form the can end along the inclined surface of the panel. Therefore, the panel of the can end is convexly upwardly swelled by a pressure of a content liquid in the can container with no influence on the stacking property of the can end when the can is used as the can container after the can end is seamed, and the bent pull-tab is upwardly lifted along with the rivet to spread the interval between the tab tail and the panel than ever before.
An easy-open can end according to an embodiment of the present invention includes a score that is carved into a faucet shape in an upper surface of a panel, an opening piece that is surrounded by the score, and a pull-tab that is fixed to a center in the upper surface of the panel with a rivet interposed therebetween, wherein the opening piece is pushed down to open a can while the score is rip-opened by a nose portion of the pull-tab, an inclined surface is formed such that the center of the panel becomes a maximum concave portion in a direction of a tab tail of the pull-tab from the center of the panel, a lower surface of the pull-tab abuts on or is brought close to the inclined surface along the inclined surface, the pull-tab has a pit in an outer rim, the pit being formed by pressing-down forming, and the pull-tab is bent by the pit.
In the easy-open can end according to an embodiment of the present invention, preferably the outer rim in which the pit is provided has a range sandwiched between two tangential lines, the tangential lines being drawn to an outer circumference of the rivet so as to be orthogonal to a direction from the rivet toward the tab tail. When the pit is provided within the range of the outer rim, the pit is substantially matched with the center of the inclined surface of the panel. Therefore, the bending of the pull-tab is substantially matched with the position of the inclined surface of the panel, and the pull-tab easily follows the panel.
In the easy-open can end according to an embodiment of the present invention, preferably an angle formed between the inclined surface of the panel and a horizontal surface ranges from 1 to 3°. When the angle ranges from 1 to 3°, a risk of generating the problem with the stacking property of the can end is eliminated, and the interval between the tab tail and the panel can sufficiently be spread in upwardly convexly swelling the panel of the can end at the point of use.
In the easy-open can end according to an embodiment of the present invention, preferably the maximum concave portion in the center of the panel has a concave amount of 0.1 to 0.5 mm. When the maximum concave portion has the concave amount of 0.1 to 0.5 mm, a risk of disrupting the stacking property of the can end is eliminated, and the interval between the tab tail and the panel can sufficiently be spread in upwardly convexly swelling the panel of the can end at the point of use.
An easy-open can end manufacturing method according to an embodiment of the present invention includes a process for carving a score into a faucet shape in an upper surface of a panel; and a process for fixing a pull-tab to the upper surface of the panel with a rivet interposed therebetween, the rivet being located in center of the panel, wherein part of an outer rim of the pull-tab is pressed down after or at the same time as the process for fixing the pull-tab to the panel.
In the easy-open can end manufacturing method according to an embodiment of the present invention, preferably, in the process for pressing-down forming, an inclined surface is formed by pushing down the center of the panel such that the center of the panel becomes a maximum concave portion with respect to a direction of a tab tail of the pull-tab from the center of the panel, a pit is formed in part of the outer rim of the pull-tab, and the pull-tab is formed such that the pull-tab is bent by the pit to abut on the inclined surface or to bring a lower surface of the pull-tab close to the inclined surface along the inclined surface. While the panel is pushed down and inclined by one-time pressing-down forming, the pull-tab is bent along the inclined surface of the panel. Therefore, the easy-open can end of an embodiment of the present invention can be manufactured simply and efficiently.
A beverage product according to an embodiment of the present invention with which a can container is filled, the can container being sealed by the easy-open can end according to an embodiment of the present invention.
In the easy-open can end of an embodiment of the present invention, the strength of the pull-tab is maintained without degrading the stacking property of the can end, and the tab tail of the pull-tab is sufficiently uplifted from the can end when the can end is used as part of the can container after seamed, so that the finger catching property of the pull-tab can largely be improved. In the easy-open can end manufacturing method of an embodiment of the present invention, the easy-open can end of an embodiment of the present invention can be manufactured simply and efficiently. In the beverage product of an embodiment of the present invention, the can container sealed by the easy-open can end of an embodiment of the present invention is easily opened.
Action of an easy-open can end according to an embodiment of the present invention will be described below. As illustrated in
The embodiment of the present invention will be described with reference to
The inclined surface 23 formed in the panel 3 may be located within a range where the pull-tab 7 can follows the shape of the inclined surface 23. In
In the embodiment, because the pull-tab 7 follows the inclined surface 23 of the panel 3, the pull-tab 7 is bent from the starting point of the neighborhood of the rivet 5 corresponding to the maximum concave portion of the panel 3 with an angle subsequently matched with the inclined angle of the panel 3.
In the embodiment, preferably the interval between the tab tail 15 and the panel 3 ranges from 0 to 0.3 mm. When the tab tail 15 is uplifted more than 0.3 mm, the tab tail 15 comes into contact with the backside of the can end located above in stacking the can ends, and sometimes the stacking property of the can end is possibly degraded.
In the easy-open can end 1 of the embodiment, a pit S is provided in part of an outer rim 11 of the pull-tab 7 by pressing-down forming, thereby bending the pull-tab 7.
In the embodiment, desirably the pit S is formed into a wedge shape such that the pull-tab 7 is easy to bend. In the embodiment, desirably the pit S has a depth of 0.05 to 0.1 mm. Sometimes the pull-tab 7 is insufficiently bent when the depth of the pit is lower than 0.05 mm, and sometimes the stacking property of the can end is degraded when the depth of the pit is more than 0.1 mm.
In the embodiment, preferably the pit S is provided in the outer rim 11 in a range sandwiched between two tangential lines L1 and L2 which are drawn in outer circumference of the rivet 5 so as to be orthogonal to a direction from the rivet 5 toward the tab tail 15. When the pit S is provided in the outer rim 11 in the range, as illustrated in
In an easy-open can end 1 of the embodiment, preferably an angle formed between the inclined surface of the panel 3 and a horizontal surface ranges from 1 to 3°. When the angle is lower than 1°, because the bending amount of the pull-tab 7 which should follow the inclined surface of the panel 3 is decreased, sometimes the interval between the tab tail 15 and the panel 3 can insufficiently be spread in convexly upwardly swelling the panel 3 of the can end 1. Sometimes the stacking property of the can end is degraded when the angle is more than 3°.
In an easy-open can end of the embodiment, preferably the maximum concave portion in the center of the panel 3 has a concave amount of 0.1 to 0.5 mm. When the concave amount is smaller than 0.1 mm, sometimes the interval between the tab tail 15 and the panel 3 can insufficiently be spread in convexly upwardly swelling the panel 3. Sometimes the stacking property of the can end is degraded when the concave amount is more than 0.5 mm.
A representative example of the easy-open can end manufacturing process of the embodiment will be described below. In the can end manufacturing process including a process of carving the score 17 into the faucet shape in the panel 3 and a process of fixing the pull-tab 7 to the center of the panel 3 with the rivet 5, the easy-open can end 1 manufacturing method of the embodiment includes a process of pressing-down part of the outer rim 11 of the pull-tab 7 after the process of fixing the pull-tab 7 to the panel 3. The pressing-down is performed while the pull-tab 7 is fixed to the panel 3, whereby the bending angle α of the pull-tab 7 is easily brought close to the inclined angle of the panel 3. The pressing-down process and the process for fixing the pull-tab 7 to the panel 3 may simultaneously be performed. The riveting and the pressing-down forming can be performed by the one-time pressing process.
The pressing-down forming may be performed by any method as long as the depth of the pit S can be formed to an extent in which the bending strength of the pull-tab 7 is not degraded with respect to the outer rim 11 of the pull-tab 7. However, desirably the pressing-down forming is performed by forming the wedge-shaped recess in order to further generate the upwardly bending effect of the pull-tab 7.
In a method for manufacturing the easy-open can end 1 of the embodiment, in the process for pressing-down the pull-tab 7, preferably the center of the panel 3 is simultaneously pressed down, and the bending is performed while the pit S is provided in the outer rim 11 of the pull-tab 7. That is, the center of the panel 3 is pushed down by the process for pressing-down the outer rim 11 of the pull-tab 7, the inclined surface 23 is formed in the direction from the rivet 5 toward the tab tail 15 such that the center of the panel 3 becomes the maximum concave portion, and the pit S is formed in part of the outer rim 11 of the pull-tab 7 to bend the pull-tab 7. Preferably, the pull-tab 7 is formed such that the lower surface of the pull-tab 7 abuts on or is brought close to the inclined surface 23 along the inclined surface 23. When the push-down of the panel 3 and the bending of the pull-tab 7 are simultaneously performed by the one-time pressing-down forming, the pull-tab 7 is bent along the inclined surface 23 of the panel 3, and the bending angle α of the pull-tab 7 can be brought close to the inclined angle of the panel 3. Therefore, the uplifting amount of the tab tail 15 does not degrade the stacking property of the can end, and the easy-open can end of the embodiment can be manufactured simply and efficiently.
In the can container sealed by the easy-open can end of the embodiment, no problem is generated in the can manufacturing or the filling and seaming process, and the finger catching property is improved to easily open the can. Therefore, the can container sealed by the easy-open can end of the embodiment can suitably used as the container for beverage product.
The tab tail uplifting amount that becomes an index for evaluating the finger catching property after the easy-open can end is seamed is investigated as an example for the easy-open can end having the shape of
<Method for Investigating Tab Tail Uplifting Amount>
As illustrated in
As illustrated in
A comparative example is similar to the example 1 except that the inclination of the panel and the bending of the pull-tab are eliminated while the pressing-down forming is not performed.
<Result of Investigating Tab Tail Uplifting Amount>
As can be seen from the result, in the example, compared with the comparative example, the finger catching property is significantly improved and the stacking property of the can end is not degraded.
While the present invention has been shown and described with reference to particular embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention.
Number | Date | Country | Kind |
---|---|---|---|
2007-177701 | Jul 2007 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/JP2008/061887 | 7/1/2008 | WO | 00 | 1/5/2010 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2009/005050 | 1/8/2009 | WO | A |
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5813561 | Chang et al. | Sep 1998 | A |
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20020088804 | Omura | Jul 2002 | A1 |
20050252917 | Turner et al. | Nov 2005 | A1 |
20070039961 | McEldowney et al. | Feb 2007 | A1 |
Number | Date | Country |
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56166231 | Dec 1981 | JP |
03111939 | Nov 1991 | JP |
08006746 | Feb 1996 | JP |
2002514993 | May 2002 | JP |
2002172445 | Jun 2002 | JP |
2002362553 | Dec 2002 | JP |
9838100 | Sep 1998 | WO |
Number | Date | Country | |
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20100326281 A1 | Dec 2010 | US |