Fou Duan

Abstract

The can end has a metal end surface with an opening closed by a closure piece at the end surface bounded by a closure edge of the metal end surface, a sealing frame connected to the end surface and surrounding the opening, and a closure unit supporting the closure piece and pivotally attached to the end surface by a pivot bearing. The sealing frame and the closure unit may be releasably and liquid-tightly connected to each other via sealing ribs and associated receiving grooves. Respective latch projections are disposed in at least one sealing rib and associated receiving groove. The respective latch projections extend around the opening and engage each other rearwardly in a vertical direction transverse to a plane defined by the opening. In a start position of the closure unit, the closure piece closing the opening is flush with the surrounding end surface or offset in parallel by less than the thickness of the end surface. The latch projections of the sealing frame and the latch projections of the closure unit are vertically spaced apart from each other by a predetermined vertical offset when the closure unit is in a start position.

Description

Technical Field

[0001] The present invention relates to a can end or lid having a metal end face, a sealing frame, and a closing unit, and particularly to a can end or lid for a beverage can. In the can end, an opening is formed in the metal end face, which is bounded by a closing edge of the end face and closed by a closing piece of the metal end face. The sealing frame is made of a plastic material and is connected to the metal end face and surrounds the opening. The closing unit is made of a plastic material, supports the closing piece, and is pivotally attached to the metal end face via a pivot bearing. The sealing frame and the closing unit can be releasably and liquid-tightly connected to each other via at least one sealing rib and an associated receiving groove. Each latch projection is disposed in at least one sealing rib and an associated receiving groove. Each latch projection extends around the opening and engages with each other rearwardly in a vertical direction transverse to the plane defined by the opening. In the starting position of the closing unit, the closing piece that closes the opening is flush with the surrounding end face or is offset parallel therefrom by less than the thickness of the metal end face.

Background Art

[0002] This type of can end is used in mass-produced beverage cans, food cans, etc. By the cooperation of the sealing rib and the receiving groove, the corresponding can end can be closed again after being opened. Before opening the can end for the first time, the closing piece can be separated from the surrounding end face by a minute gap or a weakening line that extends at least cross-sectionally along the edge of the end face. Here, a sealing film made of a plastic material is provided inside the can end so as to cover the minute gap and the weakening line. After the first opening, the airtightness of the can end is ensured only by the sealing rib and the receiving groove.

[0003] A pivot bearing can be formed directly between a closing unit and a metal end face, for example, by connecting a flexible plastic strip to the closing unit at one end and to the metal end face at the other end. However, a pivot bearing can also be formed between the closing unit and a sealing frame, in which case a pivot connection also exists between the closing unit and the metal end face, as the sealing frame is fixed to the metal end face.

[0004] It has been found that moving the closing piece away from the plane defined by the opening is not exactly reversible. Because deformation is unavoidable, it is difficult to re-fit the closing piece into the opening when closing the can end again. An undesirably large force is required to push the closing piece into the opening. In certain usage scenarios, the closing piece may even abut against the edge of the opening, causing the latch projections to fail to engage with each other. In such cases, the can end is only adequately sealed. [Overview of the project] [Problems that the invention aims to solve]

[0005] The objective of this invention is to enable easier and more reliable closure of this type of can end. [Means for solving the problem]

[0006] This objective is satisfied by a can end having the features of claim 1.

[0007] According to the present invention, the latch projection of the sealing frame and the latch projection of the closing unit are separated from each other vertically by a predetermined vertical offset when the closing unit is in the starting position.

[0008] The vertical offset allows for some play in the latch projection. This play compensates for deformation and positional changes of the closing piece after the can end is initially opened. Therefore, even if the closing piece cannot return to its original position, latch engagement between the sealing frame and the closing unit is possible, in a position flush with the surrounding end face. Thus, the airtightness and secure closure of the can end according to the present invention are guaranteed even after the initial opening.

[0009] The latch projections are preferably arranged without interruptions or with dispersed interruptions, extending around the opening. Since the shape and position of the closing piece are generally undetermined after the initial opening of the can end, it is even more preferable that vertical offsets between the latch projections exist at least substantially at each point in the path of the latch projections.

[0010] According to the present invention, the vertical offset is at least the same size as the thickness of the metal end face, preferably at least substantially the same size. In this embodiment, latch engagement between the sealing frame and the closing unit is possible even if the closing piece locally contacts the surrounding end face.

[0011] A particular embodiment of the present invention specifies that the metal end face is laminated with foil on the inside opposite the sealing frame, and the vertical offset is at least the same size as the sum of the thickness of the metal end face and the thickness of the foil, preferably at least substantially the same size. This allows for a latch engagement between the sealing frame and the closing unit, even if the closing piece abuts the upper side of the surrounding end face with its lower foil.

[0012] According to a further embodiment of the present invention, the vertical offset is 0.05 mm or more and 2 mm or less, preferably 0.2 mm or more and 1 mm or less, and particularly preferably 0.35 mm or more and 0.55 mm or less. This has proven to be particularly advantageous in practice.

[0013] The latch projection is formed by surface portions that extend at least substantially parallel to each other and / or obliquely to the plane defined by the opening.

[0014] The metal end face is made of aluminum.

[0015] The sealing frame and the closing unit come into contact with each other when the closing unit is in its starting position. In this embodiment, the vertical play of the closing unit is limited on one hand by the contact surfaces and on the other hand by latch projections that engage with each other at the rear.

[0016] The present invention relates to a can end or can lid, particularly for beverage cans, having a metal end face, a sealing frame, and a closing unit. In the can end or can lid, the metal end face has an opening formed therein, which is bounded by a closing edge of the end face and closed by a closing piece of the metal end face. The sealing frame is made of a plastic material and is connected to the metal end face and surrounds the opening. The closing unit is made of a plastic material and supports the closing piece and is pivotally attached to the metal end face via a pivot bearing. The sealing frame and the closing unit can be releasably and liquid-tightly connected to each other via at least one sealing rib and associated receiving grooves. Each latch projection is positioned in at least one sealing rib and associated receiving groove. Each latch projection extends around the opening and engages with each other rearward in a vertical direction across the plane defined by the opening.

[0017] According to the present invention, the latch projection extends around the opening along with dispersed interrupted portions. This provides a reinforcing web that improves the stability of the latch connection. Preferably, the interrupted portions are uniformly distributed along the perimeter of the opening.

[0018] Further developments of the present invention can be understood from the dependent claims, the following description, and the accompanying drawings.

[0019] The present invention will be described below with reference to the drawings. [Brief explanation of the drawing]

[0020] [Figure 1]Partial perspective view of the can end according to the present invention. [Figure 2] The can end according to FIG. 1 is shown in a cross-sectional view before the first opening. [Figure 3] It is an enlarged cross-sectional view of FIG. 2. [Figure 4] The can end according to FIG. 1 is shown in a cross-sectional view after the first opening in a re-closed state. [Figure 5] It is an enlarged cross-sectional view of FIG. 4. [Figure 6] It is a plan view of a plastic part forming a sealing frame, a closing unit, and a tear release member of the can end according to the present invention.

Embodiments for Carrying Out the Invention

[0021] FIGS. 1 and 2 show a can end or lid 11 particularly intended for beverage cans, and a re-closable opening system 15 is incorporated in its metal end face 13. The can end 11 can be connected to an associated container, not shown, via a beaded edge 17. An opening is provided in the metal end face 13, and the opening is closed in the form of a closing piece 19 by a part of the metal end face 13 in the shipped state of the can end 11 shown in FIGS. 1 and 2. The closing piece 19 is separated from the surrounding metal end face 13 by a minute gap or a weakened line (not shown).

[0022] The metal end face 13 is preferably formed from a metal layer of an aluminum or tin plate. Although not shown, a plastic sealing film foil may be attached to the inside of the can end 11.

[0023] The re-closable opening system 15 includes a sealing frame 21 made of a plastic material that surrounds the opening and is fixedly connected to the surrounding metal end face 13. Further, a closing unit 25 made of a plastic material is provided to support the closing piece 19. The closing piece 19 is attached to the sealing frame 21 via a first pivot bearing 27 and is thus pivotally attached to the surrounding end face 13.

[0024] The annular tear-release member 29 (Figure 2) is preferably also made of plastic and is connected to or molded directly to the closing unit 25, and thus fixed to the closing piece 19. By pulling the tear-release member 29, the user can pivot the closing piece 19 upward from the opening plane 33 defined by the opening, and thus release the opening, while potentially peeling off the sealing film. The connection between the tear-release member 29 and the closing unit 25 is provided by a second pivot bearing 35 (Figure 1) positioned directly opposite the first pivot bearing 27. Note that the tear-release member 29 is omitted in Figure 1.

[0025] As can be seen from the enlarged detail view in Figure 3, radially outer sealing ribs 41 and radially inner sealing ribs 42 are formed on the sealing frame 21. Furthermore, radially outer receiving grooves 43 and radially inner receiving grooves 44 are formed on the closing unit 25. The mutually engaging sealing ribs 41, 42 and receiving grooves 43, 44 enable a releasable liquid-tight connection between the sealing frame 21 and the closing unit 25. Thus, the can end 11 is resealable. It is understood that the sealing ribs 41, 42 may also be located on the closing unit 25, and the receiving grooves 43, 44 may also be located on the sealing frame 21. Depending on the requirements of the application, two or more pairs of sealing ribs 41, 42 and receiving grooves 43, 44 may also be provided.

[0026] In the radially outer sealing rib 41 and the radially outer receiving groove 43, the respective latch projections 45 and 46 are formed in the form of inclined surfaces that engage with each other at the rear so as to overlap in a vertical direction 47 across the opening plane 33. The latch projections 45 of the sealing frame 21 and 46 of the closing unit 25 extend parallel to each other and extend around the entire perimeter of the opening.

[0027] Figure 3 shows the re-closable opening system 15, in particular the closing unit 25 in the starting position that exists before the initial opening. In the starting position, the closing piece 19 is flush with the surrounding end face 13 (Figure 1). That is, the closing piece 19 extends into the opening plane 33. Furthermore, as can be seen in Figure 3, when the closing unit 25 is in the starting position, the sealing ribs 41, 42 are in contact with the bottom of the receiving grooves 43, 44.

[0028] However, when the closing unit 25 is in the starting position, the latch projection 45 of the sealing frame 21 does not contact the latch projection 46 of the closing unit 25. Rather, the latch projections 45 and 46 move vertically 47 by a predetermined vertical offset 49 so that there is free space 50 between the latch projections 45 and 46. The vertical offset 49 is preferably selected to be as large as the thickness of the metal end face 13 plus the thickness of the foil. Specifically, the vertical offset 49 can be at least 0.35 mm and at most 0.55 mm.

[0029] During the initial opening of the can, the user pulls the tear-open member 29, thereby rotating the closing unit 25 upward from the opening plane 33 by the closing piece 19. At this point, the latch connection between the closing unit 25 and the sealing frame 21 is released, and the closing piece 19 is lifted from the metal end face 13. The contents of the can can then be removed through the resulting opening. As the closing unit 25 with the closing piece 19 rotates back, the latch connection between the closing unit 25 and the sealing frame 21 is re-established so that the opening is tightly sealed again. The opening and closing procedure can then be repeated as many times as needed.

[0030] Figures 4 and 5 show the re-closed system 15 in the re-closed state after the initial opening. Due to unavoidable deformation and positional changes, it is generally impossible to precisely re-fit the closing piece 19 into the opening and thus return it to its flush initial state. Rather, the closing piece 19 abuts against the edge of the opening in places and, therefore, as a whole, remains slightly above the opening plane 33. However, the vertical offset 49 (Figure 3) present in the initial position allows the closing unit 25 sufficient vertical play 47 to compensate for the mispositioning of the closing piece 19. Despite the misalignment, the latch projections 45, 46 can engage with each other at the rear, and as a result, the sealing frame 21 and the closing unit 25 are securely latched (fitted) with each other even in the re-closed state. Thus, the can end 11 according to the present invention prevents leakage and unintended opening.

[0031] Figure 6 shows an integrated plastic component 55 comprising a sealing frame 21, a closing unit 25, and a tear-opening member 29. It can be seen that the radially outer sealing rib 41 and radially outer receiving groove 43 (including latch projections 45, 46, which are not visible in Figure 6) are interrupted by a recess 57 and a reinforcing web 59. That is, the radially outer sealing rib 41 extends around the opening with interruptions uniformly distributed in the form of recesses 57. Similarly, the radially outer receiving groove 43 extends around the opening with interruptions uniformly distributed in the form of reinforcing webs 59. The reinforcing webs 59 fit into recesses 57. This is advantageous in that material leakage is prevented, and therefore the latch engagement is more stable and reliable overall and is fully provided around the opening. However, the latch projections 45, 46 can also generally extend around the opening without interruptions.

[0032] In the initial state, the closing piece 19 does not need to be coplanar with the surrounding end face 13. Rather, in the initial state, in order to form a cutting edge for better cutting of the inner foil, the closing piece 19 may be offset laterally and parallel to the opening plane 33 from the metal end face 13 by less than the thickness of the metal plate, for example, up to 80% of the metal plate. [Explanation of symbols]

[0033] 11 Can end 13 Metal end face 15. Re-closable open system 17 Beaded Edge 19 Closing piece 21 Sealed Frame 25 Closed Units 27. First pivot bearing 29 Tear-opening member 33 Opening plane 35. Second pivot bearing 41 Radial outer sealing ribs 42 Radially inward sealing ribs 43 Radially outer receiving groove 44 Radially inward receiving groove 45 Latch projection of sealing frame 45 46 Closure unit of the closure unit 47 Vertical 49 Vertical Offset 50 free space 55 Plastic parts 57 Recess 59 Reinforcement Web

Claims

1. It has a metal end face (13), a sealing frame (21), and a closing unit (25), The metal end face (13) has an opening formed therein, the boundary of which is defined by the closing edge of the end face and which is closed by the closing piece (19) of the metal end face (13). The sealing frame (21) is made of a plastic material and is connected to the metal end face (13) and surrounds the opening. The closing unit (25) is made of a plastic material and supports the closing piece (19), and is pivotably mounted to the metal end face (13) via a pivot bearing (27). The sealing frame (21) and the closing unit (25) can be releasably and liquid-tightly connected to each other via at least one sealing rib (41) and associated receiving groove (43). Each latch projection (45, 46) is positioned in at least one of the sealing ribs (41) and the associated receiving groove (43), Each of the latch projections (45, 46) extends around the opening and engages with each other in a vertical direction (47) across the plane (33) defined by the opening. At the starting position of the closing unit (25), the closing piece (19) that closes the opening is flush with the surrounding metal end face (13) or offset parallel to it by less than the thickness of the metal end face (13), particularly in the case of a can end (11) for a beverage can, The latch projection (45) of the sealing frame (21) and the latch projection (46) of the closing unit (25) are separated from each other vertically (47) by a predetermined vertical offset (49) when the closing unit (25) is in the starting position, and the vertical offset (49) is at least the same size as the thickness of the metal end face (13), characterized in that the can end is such that the latch projection (45) of the sealing frame (21) and the latch projection (46) of the closing unit (25) are separated vertically (47) by a predetermined vertical offset (49), and the vertical offset (49) is at least the same size as the thickness of the metal end face (13).

2. The can end according to claim 1, characterized in that the latch projections (45, 46) extend around the opening together with or without interrupted portions (57, 59).

3. The metal end face (13) is laminated with foil on the inner side opposite to the sealing frame (21). The can end according to claim 1, characterized in that the vertical offset (49) is at least the same size as the sum of the thickness of the metal end face (13) and the thickness of the foil.

4. The can end according to claim 1, characterized in that the vertical offset (49) is 0.05 mm or more and 2 mm or less.

5. The latch projections (45, 46) are at least substantially parallel to each other, and / or the It is formed by a surface portion that extends obliquely to the plane (33) defined by the opening. The can end according to claim 1, characterized by the following:

6. The can end according to claim 1, characterized in that the metal end face (13) is made of aluminum.

7. The can end according to claim 1, characterized in that the sealing frame (21) and the closing unit (25) each have contact surfaces that come into contact with each other when the closing unit (25) is in the starting position.

8. It has a metal end face (13), a sealing frame (21), and a closing unit (25), The metal end face (13) has an opening formed therein, the boundary of which is defined by the closing edge of the end face and which is closed by the closing piece (19) of the metal end face (13). The sealing frame (21) is made of a plastic material and is connected to the metal end face (13) and surrounds the opening. The closing unit (25) is made of a plastic material and supports the closing piece (19), and is pivotally mounted to the metal end face (13) via a pivot bearing (27). The sealing frame (21) and the closing unit (25) can be releasably and liquid-tightly connected to each other via at least one sealing rib (41) and associated receiving groove (43), Each latch projection (45, 46) is positioned in at least one of the sealing ribs (41) and the associated receiving groove (43), Each of the latch projections (45, 46) extends around the opening and engages with each other in a vertical direction (47) across the plane (33) defined by the opening. At the starting position of the closing unit (25), the closing piece (19) that closes the opening is flush with the surrounding metal end face (13) or offset parallel to it by less than the thickness of the metal end face (13), particularly in the case of a can end (11) for a beverage can, The latch projection (45) of the sealing frame (21) and the latch projection (46) of the closing unit (25) are separated from each other vertically (47) by a predetermined vertical offset (49) when the closing unit (25) is in the starting position, and the latch projections (45, 46) extend around the opening together with distributed interrupted portions (57, 59) in a can end.

9. The can end according to claim 3, characterized in that the vertical offset (49) is at least substantially exactly the same size as the sum of the thickness of the metal end face (13) and the thickness of the foil.

10. The can end according to claim 4, characterized in that the vertical offset (49) is 0.2 mm or more and 1 mm or less.

11. The can end according to claim 10, characterized in that the vertical offset (49) is 0.35 mm or more and 0.55 mm or less.

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