US20260015126A1
CAN LID AND CAN CONTAINER
Publication
Application
Classifications
IPC Classifications
CPC Classifications
Applicants
DAIWA CAN COMPANY
Inventors
Masahiro Shiotani, Rio Miyashita, Tomoyuki Murakami
Abstract
The can lid includes a panel portion, a score line formed on the panel portion, a tab for breaking the score line, and a raised portion formed on a bottom portion of at least a part of the score line and forming a valley portion between an inner surface of the score line and the raised portion.
Figures
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001]This application is a Continuation application of PCT Application No. PCT/JP2024/013307, filed Mar. 29, 2024 and based upon and claiming the benefit of priority from Japanese Patent Application No. 2023-055767, filed Mar. 30, 2023, the entire contents of all of which are incorporated herein by reference.
FIELD
[0002]The present invention relates to a can lid and a can container.
BACKGROUND
[0003]A technique has been known in which a can lid used for a can container includes a panel portion and a tab, and a score line formed in the panel portion is broken by operating the tab. Further, a full-open type can lid (FOE) is known in which a ring-shaped score line is formed over the entire peripheral portion of the panel portion, and an opening portion is provided in the entire panel portion. Further, Jpn. Pat. Appln. KOKAI Publication No. 2004-161360 discloses a can lid including a ring-shaped score line formed around a peripheral portion of a panel portion to define an opening piece and also an auxiliary score line as a score line formed in a vicinity of a rivet portion for attaching an opening tab.
[0004]In such a can lid, in the case where the tab is lifted at the time of opening the lid, the auxiliary score line is broken due to a lever action with a tip portion of the tab as a fulcrum. In the case where the tab is further lifted from the state in which the auxiliary score line is broken, the score line near the tip portion of the tab is broken. Then, the tab is pulled up to break the ring-shaped score line along the circumferential direction, and the opening piece is removed from the panel portion.
SUMMARY
[0005]According to an aspect of the present invention, a can lid includes a panel portion, a score line formed in the panel portion, a tab configured to break the score line, and a raised portion formed at a bottom portion of at least a part of the score line and forming a valley portion between an inner surface of the score line and the raised portion.
BRIEF DESCRIPTION OF THE DRAWING(S)
[0006]
[0007]
[0008]
[0009]
[0010]
[0011]
[0012]
DETAILED DESCRIPTION
[0013]Hereinafter, a configuration of a can container 100 and a can lid 1 used for the can container 100 according to an embodiment of the present invention will be described with reference to
[0014]
[0015]As shown in
[0016]The can container 100 includes the can lid 1 and a can body 101. The can container 100 is formed by filling a beverage and then seaming and fixing the can lid 1 and the can body 101 integrally by a seaming process, for example, double seaming. The can container 100 is formed by airtightly fixing the can lid 1 and the can body 101 with a fixing part 100a. The can container 100 is, for example, a so-called two-piece can in which a bottom portion 112 and a body portion 111 of the can body 101 are integrated.
[0017]As shown in
[0018]As a specific example, as shown in
[0019]As shown in
[0020]As shown in
[0021]As shown in
[0022]The score line forming the score 31 is a groove constituting a fragile portion that allows a part of the panel portion 21 to be broken in the shape of the opening portion by an external force. The score line forming the score 31 is, for example, a wedge-shaped groove provided on an outer surface of the panel portion 21, and a part of the panel portion 21 is formed to be thin by the score 31. Here, the outer surface of the panel portion 21 is a main surface exposed to the outside in a state where the can body 101 of the can container 100 is provided with the can lid 1, that is, a surface constituting an upper surface of the can container 100.
[0023]The score 31 is formed in, for example, a safety portion 34 provided on the outer peripheral edge side of the panel portion 21. As a specific example, the score 31 is formed on an upper surface of an intermediate layer 34e, described later, of the safety portion 34. The score 31 is not limited to the circular shape, and may be formed in an arc shape that is partially intermittent, for example, and may be configured such that most of the panel portion 21 is opened and the opened opening piece is partially continuous with the panel portion 21.
[0024]As shown in
[0025]The rivet portion 32 protrudes in a columnar shape from one main surface of the panel portion 21. The rivet portion 32 is formed by a rivet-shaping step which adopts a coining process on a part of the panel portion 21 (a part of the panel portion is subjected to a coining process so that a rivet-like projection is formed). For example, as shown by the two-dot chain line in
[0026]As shown in
[0027]The main score line 41 is a groove constituting the fragile portion that allows a part of the panel portion 21 to be broken in the shape of the opening portion by an external force. The main score line 41 is, for example, a wedge-shaped groove provided on the outer surface of the panel portion 21. A part of the panel portion 21 is formed to be thin by the main score line 41. As shown in
[0028]As shown in
[0029]As shown in
[0030]As shown in
[0031]As shown in
[0032]As shown in
[0033]The raised portion 41d is formed in at least a part of the main score line 41 (score line) in the extending direction. In the present embodiment, the raised portion 41d is formed on the entire bottom portion in the extending direction of the main score line 41. The raised portion 41d is integrally formed with the bottom portion of the main score line 41 and protrudes from the bottom portion of the main score line 41. The raised portion 41d is formed by moving the material of the panel portion 21 on which the score line is formed, or by a jig or the like for forming the score line.
[0034]Examples of the shape of the raised portion 41d will be described with reference to
[0035]The height of the raised portion 41d from the bottom portion of the main score line 41, that is, the depth of the valley portion 41e, is set to, for example, a range of 0.5% to 11%, preferably a range of 1% to 9%, with respect to the remaining thickness of the bottom portion of the main score line 41 (score line). Here, the remaining thickness of the bottom portion of the score line is the thickness of the panel portion 21 from the bottom portion of the score line (the bottom of the valley portion 41e) excluding the raised portion 41d to the main surface of the panel portion 21 on the side opposite to the main surface on the side where the score line is formed.
[0036]For example, at point E of the first portion 41a shown in
[0037]In addition, for example, the raised portion 41d is preferably higher at a position separated from the start of breaking than at the position of the start of breaking of the main score line 41. As a specific example, the raised portion 41d is set such that the height of the raised portion 41d at the second portions 41b (point F, point G), which is a position separated from the start of breaking, is higher than the height of the raised portion 41d at the first portion 41a (point E), which is the breaking start position. As an example, the height of the raised portion 41d at the first portion 41a (point E) is 1 μm to 4 μm, and the height of the raised portion 41d at the second portions 41b (point F, point G) is 5 μm to 9 μm.
[0038]Since the raised portion 41d is formed by, for example, movement of the surrounding metallic material, etc., in the case where the height of the raised portion 41d is made larger than the range of 0.5% to 11% with respect to the remaining thickness of the bottom portion of the score line (hereinafter, referred to as the above numerical range), the inner surface of the main score line 41 (score line) collapses. As a result, the score shape collapses, and the strength may be weakened. If the raised portion 41d is smaller than the above numerical range, the strength for suppressing derailment may not be maintained. Therefore, in order to maintain the score shape and improve the lid openability, the raised portion 41d is preferably in the above numerical range. The numerical value is not limited to the above range, however, as long as the strength of the raised portion 41d can be maintained, the score shape can be maintained, and the lid openability can be improved, etc. by the method for manufacturing or the like.
[0039]The sub-score line 42 is provided inward in the radial direction to the main score line 41. The sub-score line 42 is formed in parallel with the main score line 41. The sub-score line 42 is, for example, a wedge-shaped groove provided on the outer surface of the panel portion 21. The sub-score line 42 is formed to have a depth shallower than the depth of the main score line 41. That is, the thickness of the part of the panel portion 21 where the sub-score line 42 is provided is formed to be thicker than the thickness of the part of the panel portion 21 where the main score line 41 is provided. A part of the panel portion 21 is formed to be thin by the sub-score line 42. The sub-score line 42 is, for example, not broken at the time the main score line 41 is broken.
[0040]As shown in
[0041]The safety portion 34 is formed by folding the panel portion 21 four times to partially form a five-layer structure. The score 31 is formed in the safety portion 34 and in a third layer of the panel portion 21. Here, the following description will be made assuming that the outer side of the panel portion 21 is a first layer and the inner side (the can body 101 side) is a fifth layer.
[0042]In the case where the tab 12 is operated to open and the score 31 is broken, the safety portion 34 forms an outer safety portion 34a that protects the inner peripheral edge of a part of the panel portion 21 that is present in the can body 101 and is broken at the score 31, and an inner safety portion 34b that protects the outer peripheral edge of a part (opening piece) of the panel portion 21 that is separated from the can body 101 and is broken at the score 31. The outer safety portion 34a is formed by the three-layer panel portion 21, and the folded portion is present at the inner peripheral edge of the opened panel portion 21. The inner safety portion 34b is formed by the three-layer panel portion 21, and the folded portion is present on an outer peripheral edge of a part separated from an opening of the panel portion 21.
[0043]To be more specific, as shown in
[0044]The outer safety portion 34a is formed by the upper layer 34c and a part of the intermediate layer 34e. The upper layer 34c is positioned above the score 31, and a part where the first layer and the second layer of the upper layer 34c are folded back and curved functions as a protection portion after the score 31 is broken.
[0045]The inner safety portion 34b is formed by a part of the intermediate layer 34e and the lower layer 34d. The lower layer 34d is located below the score 31, and a part where the fourth layer and the fifth layer of the lower layer 34d are folded back and curved functions as a protection portion after the score 31 is broken.
[0046]The finger insertion recessed portion 35 is located below the rear end of the tab 12 to which the finger is hooked, and is recessed from the outer surface of the panel portion 21.
[0047]The groove portion 22 is a ring-shaped recess that is provided continuously with the outer peripheral edge of the panel portion 21 and protrudes toward the can body side at the time the panel portion 21 is fixed to the can body. The groove portion 22 is a so-called countersink. The groove portion 22 has a function of improving the pressure resistance of the can lid 1.
[0048]A first flange portion 23 is seamed to the opening end of the can body 101. The first flange portion 23 is provided with a resin layer for sealing on a surface that abuts on the can body 101.
[0049]As shown in
[0050]The attachment portion 51 is formed in a plate shape and has a rivet hole 51a. The attachment portion 51 is continuous with the tip portion 52 and the finger hook portion 53. The rivet hole 51a is formed to have an inside diameter that allows the rivet portion 32 to be inserted. The rivet portion 32 inserted into the rivet hole 51a is caulked, so that the attachment portion 51 is fixed to the panel portion 21 with the rivet portion 32.
[0051]The tip portion 52 is formed on a tip side of the tab 12. The tip portion 52 has a tip end formed in an arc shape or a polygonal shape. The tip portion 52 is formed by, for example, bending double the outer peripheral edge except the tip end. The tip portion 52 is arranged inward in the radial direction and close to the score 31 of the panel portion 21.
[0052]The finger hook portion 53 is a part on which a finger is hooked to lift the tab 12 during operation of the tab 12 to open. As shown in
[0053]As shown in
[0054]The can body 101 includes a body portion 111, a bottom portion 112, a tapered portion 113, and a second flange portion 114. The body portion 111 is formed in a cylindrical shape. The bottom portion 112 is integrally provided at one end of the body portion 111. One end (lower end) of the tapered portion 113 is integrally continuous with the other end of the body portion 111, and the other end (upper end) of the tapered portion 113 is integrally continuous with the second flange portion 114. The tapered portion 113 gradually decreases in diameter from the body portion 111 side toward the second flange portion 114 side. The second flange portion 114 forms an opening end of the can body 101. The second flange portion 114 is fixed to the first flange portion 23 by seaming.
[0055]With the can lid 1 and the can container 100 configured as described above, the main score line 41 of the auxiliary score 33 as a score line includes the raised portion 41d formed on the bottom portion. In the main score line 41, the thickness of the raised portion 41d is larger than the valley portion 41e formed between the facing surfaces of the main score line 41 and the raised portion 41d, and thus the strength of the raised portion 41d is higher than the strength of the valley portion 41e. The valley portion 41e serves as a guide line for breaking the main score line 41. Therefore, the can lid 1 has improved breaking properties for the main score line 41 on which the raised portion 41d is formed. Therefore, it is possible to prevent derailment from occurring when the main score line 41 is broken. Accordingly, the can lid 1 has improved lid openability, and thus can suppress a lid opening failure in which a suitable lid opening is inhibited by derailing during breaking of the score line.
[0056]In the auxiliary score 33, the height of the raised portion 41d at the second portion 41b (point F, point G) of the main score line 41 is set to be higher than the height of the raised portion 41d at the first portion 41a (point E). This can further suppress the occurrence of derailment of the score line at the time the auxiliary score 33 is broken. That is, in the case where the finger hooked on the finger hook portion 53 of the tab 12 is moved in a direction away from the panel portion 21, the tip portion 52 presses the panel portion 21 with the attachment portion 51 (rivet portion 32) as a base point, and the finger hook portion 53 moves in a direction away from the panel portion 21, such that the main score line 41 of the auxiliary score 33 is broken.
[0057]At this time, the auxiliary score 33 of the attachment portion 51 is deformed, and the first portion 41a of the main score line 41 is first broken. In the case where the finger is further moved in the direction away from the panel portion 21, the second portions 41b continuous with the first portion 41a are broken, and the finger hook portion 53 of the tab 12 moves in the X direction, whereas the second portion 41b is formed in an arc shape so as to extend in a direction intersecting the X direction. Therefore, there is a high possibility of derailment to the first portion 41a side of the second portion 41b. When derailment occurs at the second portion 41b, the portion broken by the derailment reaches the attachment portion 51 (rivet portion 32) in the X direction, and the tip portion 52 cannot suitably press the panel portion 21, so that the lid openability is reduced.
[0058]However, in the main score line 41 of the embodiment, the height of the raised portion 41d in the second portion 41b is made higher than that of the first portion 41a, and the depth of the valley portion 41e in the second portion 41b is made deeper than that of the first portion 41a, so that the strength of the second portion 41b is improved, and the breakage is suitably guided. This can further prevent the main score line 41 from derailing in the second portion 41b.
[0059]As described above, in the can lid 1, the depth of the valley portion 41e in the second portion 41b of the main score line 41 is made deeper than that of the valley portion 41e in the first portion 41a, and thus, it is possible to further suppress degradation of the lid openability.
[0060]Further, since the can container 100 is a positive pressure can, the pressure applied by the internal pressure to the breaking portion of the main score line 41 immediately after the lid is opened becomes large, and thus the breaking of the main score line 41 of the auxiliary score 33 is accelerated by the internal pressure. However, by providing the raised portion 41d in the main score line 41 and forming the valley portion 41e with the raised portion 41d, the derailment of the main score line 41 during initial breakage can be suppressed by the increase in the thickness due to the raised portion 41d and the guidance of the breakage by the valley portion 41e. That is, even when the can container 100 is a positive pressure can, the derailment can be suppressed by providing the raised portion on the score line, and thus the can lid 1 can suppress the degradation of the lid openability.
[0061]As described above, according to the can lid 1 and the can container 100 of the embodiment, the lid opening failure can be suppressed by providing the raised portion at the bottom portion of the score line.
[0062]The present invention is not limited to the above-described embodiment. For example, in the above-described example, the example in which the raised portion 41d is provided on the main score line 41 of the auxiliary score 33 has been described, but the present invention is not limited thereto. For example, the raised portion may be configured to be provided on a score line forming the score 31. In the above-described example, an example in which a pair of valley portions 41e is formed in one score line (main score line 41) has been described, but the present invention is not limited thereto. For example, the valley portion 41e may be provided on one side in the direction orthogonal to the extending direction of the score line.
[0063]In the above-described example, the valley portion 41e of the main score line 41 is formed by forming the raised portion 41d over the entire main score line 41. However, the raised portion 41d (valley portion 41e) may be provided only on a part of the main score line 41, specifically, the second portion 41b where derailment is likely to occur. That is, since the raised portion is configured to form a valley portion in the score line and guide the breakage using the valley portion, the raised portion may be configured to be provided in a location where derailment is likely to occur due to the shape of the score line.
[0064]In the example described above, as the score line forming the valley portions by the raised portion, the configuration in which the raised portion 41d is provided on the main score line 41 of the auxiliary score 33 has been described, but the configuration is not limited thereto, and the raised portion may be provided on the score 31. The can lid 1 provided with the score line is not limited to the can lid (FOE), and can be applied to various lids as long as the configuration is provided with the score line. Similarly, the can container 100 using the can lid 1 is preferably a positive pressure can, but may be a negative pressure can. Even in the can container 100 of the negative pressure can, derailment of the score line can be prevented as long as the valley portion is formed by providing the raised portion in the score line. In the example described above, the panel portion 21 of the can lid 1 has a circular shape, but the present invention is not limited thereto, and the panel portion 21 may have a rectangular shape. The content of the can container 100 is not limited to sparkling content, and may be a solid material in addition to or instead of a fluid such as a liquid.
[0065]That is, the present invention is not limited to the above-described embodiments, and can be modified in various ways without departing from the gist thereof in the implementation stage. The embodiments may be combined as appropriate for implementation, and in that case combined effects will be obtained. Furthermore, the above embodiments include various inventions, and various inventions can be derived by combinations selected from a plurality of disclosed constituent elements. For example, even if some of the constituent elements are deleted from all the constituent elements shown in the embodiments, if the problem can be solved and an effect can be obtained, the configuration from which the constituent elements are deleted can be derived as the invention.
Claims
1. A can lid, comprising:
a panel portion;
a score line formed on the panel portion;
a tab configured to break the score line; and
a raised portion formed at a bottom portion of at least a part of the score line and forming a valley portion between an inner surface of the score line and the raised portion.
2. The can lid according to
the panel portion includes:
a circular score for an opening, the circular score being formed by the score line;
a rivet portion adjacent to an inner side of the score, and to which the tab is fixed; and
an auxiliary score formed on a side of the rivet portion that is opposite from the score, the auxiliary score being formed by the score line at least partly including the raised portion and provided adjacent to a side of the rivet portion that is near a center of the panel portion.
3. The can lid according to
a height of the raised portion from the bottom portion of the score line is in a range of 0.5% to 11% with respect to a remaining thickness of the bottom portion of the score line where the raised portion is provided.
4. A can container, comprising:
the can lid according to
a can body to which the can lid is seamed.
5. The can container according to
6. A can container, comprising:
the can lid according to
a can body to which the can lid is seamed.
7. The can container according to
8. A can container, comprising:
the can lid according to
a can body to which the can lid is seamed.
9. The can container according to