A tear-off lid to prevent tab lifting

Abstract

The application relates to the technical field of easy-to-tear covers, in particular to an easy-to-tear cover capable of preventing a pull ring from being raised, which comprises a cover body and an aluminum foil layer covering the middle part of the cover body, the middle part of the cover body is provided with an opening, the aluminum foil layer corresponds to and covers the upper part of the opening of the cover body, the aluminum foil layer is hot-sealed and adhered to the edge of the opening of the cover body through hot-sealing glue, a pull ring is arranged above the edge of the aluminum foil layer, the aluminum foil layer is provided with a raised structure, and the raised structure forms a limiting structure for the pull ring. The application provides the easy-to-tear cover capable of preventing the pull ring from being raised, which simultaneously solves the problems of the pull ring being raised, shifted and material redundancy and the limited optimization space of the cost.

Description

Technical Field

[0001] This application relates to the field of easy-tear cap technology, and more particularly to an easy-tear cap that prevents the pull tab from lifting. Background Technology

[0002] In related technologies, easy-tear caps are widely used in food packaging such as milk powder, coffee powder, and tea. Through a sealing process with the can body, they form a high-barrier container for storing various foods. Because easy-tear caps belong to the packaging field, they require high levels of sealing and ease of opening.

[0003] However, existing easy-tear caps have the following drawbacks: the pull tab is not bonded to the aluminum foil, making it prone to lifting, which can damage the aluminum foil, cause sealing failure, or make opening difficult. Therefore, it is clear that the pull tab in related technologies, which easily lifts, leading to sealing failure or opening difficulty, has significant drawbacks. Utility Model Content

[0004] To address the aforementioned shortcomings, this application provides an easy-tear cap that prevents the pull tab from lifting.

[0005] An easy-tear cap to prevent pull ring from lifting includes a cap body and an aluminum foil layer covering the middle of the cap body. The cap body 1 has an opening in the middle, and the aluminum foil layer covers the opening of the cap body. The aluminum foil layer is provided with a raised structure, and the raised structure forms a limiting structure for the pull ring.

[0006] Furthermore, the protruding structure includes a reinforcing protrusion and a limiting protrusion, with the top of the limiting protrusion wrapping around the pull ring to form the limiting structure.

[0007] Furthermore, the raised structure includes reinforcing protrusions, and the aluminum foil layer forms a relief area adapted to the pull ring through the reinforcing protrusions. The top height of the reinforcing protrusions is not lower than the height of the pull ring, and the limiting structure is formed around the reinforcing protrusions in the relief area.

[0008] Furthermore, a liftable mold is provided below the inner diameter of the easy-tear cap pull ring; the liftable mold lifts the aluminum foil layer upward through the inner hole of the pull ring to form a bowl-shaped protrusion, and then applies pressure in the opposite direction, driving the aluminum foil to undergo radial cold working and extension deformation, causing the top of the bowl-shaped protrusion to fold outward and curl downward to form a ring-shaped first rolled edge; the outer diameter of the first rolled edge expands to exceed the diameter of the inner hole of the pull ring, and the inner wall of the first rolled edge and the edge of the inner hole of the pull ring form a mechanical wrapping angle, forming a continuous or partially intermittent interference riveting structure; the riveting structure includes, in sequence: a first horizontal part connected to the cap body, a downwardly curled constraint first rolled edge, and a second horizontal part extending outward of the pull ring; through mechanical interference constraint, the first rolled edge generates a radial clamping force pointing towards the axis of the pull ring, realizing rigid self-locking and completely eliminating the pull ring lifting.

[0009] Furthermore, a liftable mold is provided below the outer wall of the easy-tear cap pull ring; the liftable mold lifts the aluminum foil layer upward through the outer wall of the pull ring to form an edge protrusion, and then applies pressure in the opposite direction to drive the aluminum foil to produce radial cold working extension deformation, so that the top of the edge protrusion folds inward and curls downward to form the second outer edge; the outer diameter of the second edge expands to exceed the outer wall of the pull ring, and the inner wall of the second edge and the outer edge of the pull ring form a mechanical covering angle, forming a continuous full-circle covering or partially intermittent interference riveting structure; the riveting structure includes, in sequence: a third horizontal part connected to the cap body, a downward curled constrained second edge, and a fourth horizontal part extending outward of the pull ring; through mechanical interference constraint, the second edge generates a radial clamping force pointing towards the axis of the pull ring, realizing rigid self-locking and completely eliminating the pull ring lifting.

[0010] Furthermore, the pull ring is positioned above the aluminum foil layer. No reinforcing protrusions are provided at the location of the pull ring on the aluminum foil layer. The raised areas where multiple reinforcing protrusions are located form a relief groove that wraps around the pull ring. The pull ring is positioned inside the relief groove. The height of the reinforcing protrusions is higher than the upper surface of the pull ring, thus eliminating the pull ring from lifting up.

[0011] Furthermore, the aluminum foil layer is set as a D-type aluminum foil layer with a thickness of 0.06-0.09 mm.

[0012] Further, the height of the bowl-shaped protrusion or edge protrusion is set to 1.0-1.5mm; the maximum diameter of the bowl-shaped protrusion after extension is greater than the inner diameter of the pull ring by 1.0mm±0.1mm, and the maximum length of the edge protrusion after extension is greater than the outer diameter of the pull ring by 1.0mm±0.1mm; when the inner diameter of the pull ring is continuously covered by a whole circle, the riveting coverage angle is 110°-130°; when the inner diameter of the pull ring is partially intermittently riveted, it includes ≥3 circumferentially distributed rivet points, and the coverage angle of a single rivet point is 60°-90°; when the outer wall of the pull ring is continuously covered by a whole circle, the riveting coverage angle is 110°-130°; when the outer wall of the pull ring is partially intermittently riveted, it includes ≥2 circumferentially distributed rivet points, and the coverage angle of a single rivet point is 60°-90°.

[0013] Furthermore, the aluminum foil layer is heat-sealed to the edge of the opening of the cover using heat-sealing adhesive.

[0014] Furthermore, the continuous circular riveting structure is a continuous annular covering body, and its inner wall forms a full circumferential contact constraint with the outer edge of the pull ring; the center angle distance between adjacent riveting points in the partially discontinuous interference riveting structure is ≤120°.

[0015] This application has at least one of the following beneficial effects:

[0016] 1. This application provides an easy-tear cap that simultaneously solves the problems of easy-tear cap pull ring lifting and displacement, as well as material redundancy and limited cost optimization space, and can prevent pull ring lifting. This application not only solves the problem that the pull ring of existing easy-tear caps is prone to lifting, resulting in seal damage or difficulty in opening, but also has excellent sealing performance and is convenient and quick to open; it also achieves material saving, cost reduction and optimization space, and significantly expands its application in the field of food packaging such as milk powder.

[0017] 2. In this embodiment of the application, the aluminum foil is subjected to a lifting → radial cold working and stretching process by the riveting device, so that the aluminum foil expands to form a continuous or partially intermittent interference riveting structure. This structure rigidly constrains the displacement of the pull ring through the mechanical self-locking effect, thus completely eliminating the problem of the pull ring lifting.

[0018] 3. In related technologies, the aluminum foil covering traditional easy-tear caps is usually an O-type design, which results in some material redundancy and limited room for cost optimization. This application provides an easy-tear cap that can effectively prevent the pull tab from lifting, while using a more material-saving D-type aluminum foil design. The aluminum foil consumption is approximately 89.04% of the original O-type solution, saving raw materials and reducing costs. Attached Figure Description

[0019] Figure 1 This is a front view of the easy-tear cap for preventing the pull tab from lifting, as described in Embodiment 1 of this application.

[0020] Figure 2 This is a cross-sectional view of the easy-tear cap that prevents the pull tab from lifting, as described in Embodiment 1 of this application.

[0021] Figure 3 for Figure 2 A partial enlarged view of the mid-section view.

[0022] Figure 4 This is a schematic diagram of a traditional O-ring aluminum foil structure for an easy-tear cap that prevents the pull tab from lifting, as described in an embodiment of this application.

[0023] Figure 5 This is a schematic diagram of a novel D-shaped aluminum foil structure for an easy-tear cap that prevents the pull tab from lifting, according to an embodiment of this application.

[0024] Figure 6 This is a cross-sectional view of the easy-tear cap for preventing the pull tab from lifting, as described in Embodiment 2 of this application.

[0025] Figure 7 This is a schematic diagram of the relief groove structure of the easy-tear cap that prevents the pull ring from lifting, according to Embodiment 3 of this application.

[0026] Reference numerals: 1. Cover; 2. Opening; 3. Aluminum foil layer; 4. Pull ring; 5. First horizontal part; 6. First rolled edge; 7. Bowl-shaped protrusion; 8. Heat sealant; 9. Second horizontal part; 15. Third horizontal part; 16. Second rolled edge; 17. Edge protrusion; 19. Fourth horizontal part; 20. Relief groove; 21. Reinforcing protrusion. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0028] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0029] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0030] The following is in conjunction with the appendix Figure 1-7 This application will be described in further detail.

[0031] An easy-tear cap to prevent pull ring from lifting includes a cap body 1 and an aluminum foil layer 3 covering the middle of the cap body 1. The cap body 1 has an opening 2 in the middle, and the aluminum foil layer 3 covers the opening 2 of the cap body 1. The aluminum foil layer 3 has a raised structure, which forms a limiting structure for the pull ring 4. The aluminum foil layer 3 is heat-sealed to the edge of the opening 2 of the cap body 1 by heat-sealing adhesive 8.

[0032] Example 1:

[0033] The raised structure includes a reinforcing protrusion and a limiting protrusion, with the top of the limiting protrusion wrapping around the pull ring 4 to form the limiting structure. (Refer to...) Figure 1 , Figure 2 and Figure 3 A liftable mold is provided below the inner diameter of the easy-tear cap pull ring 4. The liftable mold lifts the aluminum foil layer 3 upward through the inner hole of the pull ring 4 to form a bowl-shaped protrusion 7, and then applies pressure in the opposite direction to drive the aluminum foil to produce radial cold working extension deformation, so that the top of the bowl-shaped protrusion 7 is folded outward and curled downward to form an annular first rolled edge 6. The outer diameter of the first rolled edge 6 expands to exceed the inner hole diameter of the pull ring 4, and the inner wall of the first rolled edge 6 and the edge of the inner hole of the pull ring 4 form a mechanical covering angle, forming a continuous or partially intermittent interference riveting structure. The riveting structure includes, in sequence: a first horizontal part 5 connected to the cap body 1, a downwardly curled constraint first rolled edge 6, and a second horizontal part 9 extending outward to the pull ring 4. Through mechanical interference constraint, the first rolled edge 6 generates a radial pressing force pointing towards the axis of the pull ring 4, realizing rigid self-locking and completely eliminating the lifting of the pull ring 4.

[0034] Reference Figure 4 and Figure 5 The aluminum foil layer 3 is configured as a D-type aluminum foil layer with a thickness of 0.06-0.09 mm. The material consumption of the D-type aluminum foil layer 3 is approximately 89.04% of that of the traditional O-type aluminum foil solution, saving approximately 10.96% of the material compared to the traditional O-type aluminum foil. The height of the bowl-shaped protrusion 7 is set to 1.0-1.5 mm, and the maximum diameter of the bowl-shaped protrusion 7 after extension is greater than the inner diameter of the pull ring by 1.0 mm ± 0.1 mm. The first rolled edge 6 generates a radial clamping force F ≥ 1.5 N / mm pointing towards the axis of the pull ring. When the inner diameter of the pull ring is continuously covered by a full circle, the riveting coverage angle is 110°-130°; when the inner diameter of the pull ring is partially discontinuously riveted, it includes ≥3 circumferentially distributed riveting points, and the coverage angle of a single riveting point is 60°-90°; the continuous full circle riveting structure is a continuous annular covering body, and its inner wall forms a full circumferential contact constraint with the outer edge of the pull ring; the center angle distance between adjacent riveting points in the partially discontinuous interference riveting structure is ≤120°.

[0035] In this embodiment, the easy-tear cap to prevent the pull tab from lifting can be made primarily of tinplate, an excellent packaging material characterized by its resistance to rust, high packaging strength, and good sealing and light-blocking properties. Furthermore, by adding appropriate proportions of polyethylene, elastomers, modified polypropylene, and antioxidants to the tinplate, the resulting easy-tear cap exhibits low opening force, high tensile strength, and high impact strength. This significantly improves the pressure resistance and deformation resistance of the easy-tear cap, enhancing its overall quality and expanding its application range in packaging. Simultaneously, the riveting device performs a lifting → radial cold-working extension process on the aluminum foil, causing the foil to expand and form a continuous or partially intermittent interference-fit riveting structure. This structure rigidly constrains the pull tab displacement through a mechanical self-locking effect, completely eliminating the pull tab lifting problem.

[0036] Example 2:

[0037] Reference Figure 4 and Figure 6 The difference between this embodiment and Embodiment 1 is that: a liftable mold is provided below the outer wall of the easy-tear cover pull ring 4; the liftable mold pushes the aluminum foil layer 3 upward through the outer wall of the pull ring 4 to form an edge protrusion 17 and then applies pressure in the opposite direction, driving the aluminum foil to produce radial cold working extension deformation, so that the top of the edge protrusion 17 folds inward and curls downward to form the outer edge second rolled edge 16; the outer diameter of the second rolled edge 16 expands beyond the outer wall of the pull ring 4, and the inner wall of the second rolled edge 16 and the outer edge of the pull ring 4 form a mechanical covering angle, forming a continuous full circle covering or partially intermittent interference riveting structure; the riveting structure includes, in sequence: a third horizontal part 15 connected to the cover body 1, a downward curled constraint second rolled edge 16, and a fourth horizontal part 19 extending outward to the pull ring 4; through mechanical interference constraint, the second rolled edge 16 generates a radial pressing force pointing towards the axis of the pull ring 4, realizing rigid self-locking and completely eliminating the pull ring 4 from lifting.

[0038] The height of the edge protrusion 17 is 1.0-1.5mm, and the maximum length of the extended edge protrusion 17 is greater than the outer diameter of the pull ring by 1.0mm ± 0.1mm. The second rolled edge 16 generates a radial clamping force F ≥ 1.5N / mm pointing towards the axis of the pull ring. When the outer wall of the pull ring is continuously covered with a whole circle, the riveting coverage angle is 110°-130°; when the outer wall of the pull ring is partially intermittently riveted, it includes ≥ 2 circumferentially distributed rivet points, and the coverage angle of a single rivet point is 60°-90°.

[0039] Example 3:

[0040] The raised structure includes reinforcing protrusions. The aluminum foil layer 3 forms a clearance area adapted to the pull ring 4 through the reinforcing protrusions. The top height of the reinforcing protrusions is not lower than the height of the pull ring 4, and the limiting structure is formed around the reinforcing protrusions in the clearance area. (Refer to...) Figure 7 In this embodiment, the pull ring 4 is disposed above the aluminum foil layer 3. No reinforcing protrusions are provided at the location of the pull ring 4 on the aluminum foil layer 3. The raised areas where multiple reinforcing protrusions are located form a relief groove 20 that wraps around the pull ring 4. The pull ring 4 is disposed inside the relief groove 20. The height of the reinforcing protrusions is higher than the upper surface of the pull ring 4, thus eliminating the lifting of the pull ring 4.

[0041] In summary, this application provides an easy-tear cap that simultaneously solves the problems of pull ring lifting and displacement, as well as material redundancy and limited cost optimization space, and can prevent pull ring lifting. This application not only solves the problem that the pull ring of existing easy-tear caps is prone to lifting, leading to seal damage or difficulty in opening, but also has excellent sealing performance and is convenient and quick to open; it also achieves material saving, cost reduction and optimization space, and significantly expands its application in the field of food packaging such as milk powder.

[0042] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An easy-tear cap to prevent the pull ring from lifting, characterized in that, Includes a cover (1) and an aluminum foil layer (3) covering the middle of the cover (1). The cover (1) has an opening (2) in the middle. The aluminum foil layer (3) covers the opening (2) of the cover (1). The aluminum foil layer (3) has a raised structure and forms a limiting structure for the pull ring (4) through the raised structure.

2. The easy-tear cap for preventing the pull ring from lifting according to claim 1, characterized in that, The protruding structure includes a reinforcing protrusion and a limiting protrusion, with the top of the limiting protrusion wrapping around the pull ring (4) to form the limiting structure.

3. The easy-tear cap for preventing the pull ring from lifting according to claim 1, characterized in that, The raised structure includes reinforcing protrusions, and the aluminum foil layer (3) forms a relief area adapted to the pull ring (4) by means of the reinforcing protrusions. The top height of the reinforcing protrusions is not lower than the height of the pull ring (4), and the limiting structure is formed around the reinforcing protrusions of the relief area.

4. The easy-tear cap for preventing the pull ring from lifting according to claim 2, characterized in that, A liftable mold is provided below the inner diameter of the easy-tear cover pull ring (4); the liftable mold lifts the aluminum foil layer (3) upward through the inner hole of the pull ring (4) to form a bowl-shaped protrusion (7) and then applies pressure in the opposite direction to drive the aluminum foil to produce radial cold working extension deformation, so that the top of the bowl-shaped protrusion (7) is folded outward and curled downward to form an annular first rolled edge (6); the outer diameter of the first rolled edge (6) expands to exceed the inner diameter of the pull ring (4), and the inner wall of the first rolled edge (6) and the edge of the inner hole of the pull ring (4) form a mechanical covering angle, forming a continuous full circle covering or a partially intermittent interference riveting structure; the riveting structure includes, in sequence: a first horizontal part (5) connected to the cover body (1), a downward curled constraint first rolled edge (6), and a second horizontal part (9) extending to the outside of the pull ring (4); through mechanical interference constraint, the first rolled edge (6) generates a radial pressing force pointing to the axis of the pull ring (4), realizing rigid self-locking and completely eliminating the pull ring (4) from lifting.

5. The easy-tear cap for preventing the pull ring from lifting according to claim 2, characterized in that, A liftable mold is provided below the outer wall of the easy-tear cover pull ring (4); the liftable mold lifts the aluminum foil layer (3) upward through the outer wall of the pull ring (4) to form an edge protrusion (17) and then applies pressure in the opposite direction to drive the aluminum foil to produce radial cold working extension deformation, so that the top of the edge protrusion (17) folds inward and curls downward to form the outer edge second rolled edge (16); the outer diameter of the second rolled edge (16) expands to exceed the outer wall of the pull ring (4), and the inner wall of the second rolled edge (16) and the outer edge of the pull ring (4) form a mechanical covering angle, forming a continuous full circle covering or a partially intermittent interference riveting structure; the riveting structure includes, in sequence: a third horizontal part (15) connected to the cover body (1), a downward curled constraint second rolled edge (16), and a fourth horizontal part (19) extending to the outside of the pull ring (4); through mechanical interference constraint, the second rolled edge (16) generates a radial pressing force pointing to the axis of the pull ring (4), realizing rigid self-locking and completely eliminating the pull ring (4) from lifting.

6. The easy-tear cap for preventing pull ring from lifting according to claim 3, characterized in that, The pull ring (4) is positioned above the aluminum foil layer (3). No reinforcing protrusions are provided at the position of the pull ring (4) on the aluminum foil layer (3). The raised areas where multiple reinforcing protrusions are located form a relief groove (20) that wraps around the pull ring (4). The pull ring (4) is positioned inside the relief groove (20). The height of the reinforcing protrusions is higher than the upper surface of the pull ring (4), thus eliminating the lifting of the pull ring (4).

7. The easy-tear cap for preventing pull ring from lifting according to claim 1, characterized in that, The aluminum foil layer (3) is set as a D-type aluminum foil layer (3) with a thickness of 0.06-0.09 mm; the aluminum foil layer (3) is heat-sealed to the edge of the opening (2) of the cover (1) by heat-sealing adhesive (8).

8. The easy-tear cap for preventing pull ring from lifting according to claim 4, characterized in that, The height of the bowl-shaped protrusion (7) is set to 1.0-1.5mm; the maximum diameter of the bowl-shaped protrusion (7) after extension is greater than the inner diameter of the pull ring (4) by 1.0mm±0.1mm; when the inner diameter of the pull ring (4) is continuously covered by a whole circle, the riveting coverage angle is 110°-130°; when the inner diameter of the pull ring (4) is partially intermittently riveted, it includes ≥3 circumferentially distributed rivet points, and the coverage angle of a single rivet point is 60°-90°.

9. The easy-tear cap for preventing pull ring from lifting according to claim 5, characterized in that, The height of the edge protrusion (17) is set to 1.0-1.5mm; the maximum length of the edge protrusion (17) after extension is greater than the outer diameter of the pull ring (4) by 1.0mm ± 0.1mm; when the outer wall of the pull ring (4) is continuously covered by a whole circle, the riveting coverage angle is 110°-130°; when the outer wall of the pull ring (4) is partially intermittently riveted, it includes ≥2 circumferentially distributed rivet points, and the coverage angle of a single rivet point is 60°-90°.

10. The easy-tear cap for preventing pull ring from lifting according to claim 4, characterized in that, The continuous circular riveting structure is a ring-shaped continuous covering body, and its inner wall forms a full circumferential contact constraint with the outer edge of the pull ring (4); the center angle distance between adjacent riveting points of the partially discontinuous interference riveting structure is ≤120°.

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