A crush resistant paper tube with a flat wound end

Abstract

The application discloses a compression-resistant paper tube with a flat-wound mouth, comprising a tube body, which is integrally formed by adopting a straight tube process and is in a cylindrical structure, wherein a joint extends along the axial direction of the tube body, and an upper end opening edge of the tube body is provided with a flat-wound mouth, which is formed by folding and flattening the paper edge to the inside of the tube body and is in a U-shaped sandwich structure in a cross section. The tube body is integrally formed by adopting the straight tube process, so that the compression resistance and durability of the paper tube are improved; the flat-wound mouth is arranged on the upper end opening edge of the tube body, the paper edge is folded and flattened to the inside to form a U-shaped sandwich structure, a smooth circular arc transition is formed on the upper end edge of the tube body, vertical pressure on the top of the tube body is effectively dispersed, the structural strength of the top of the tube body is further enhanced, and sharp edge burrs caused by direct exposure of the paper edge are avoided, so that the safety in use is improved.

Description

Technical Field

[0001] This invention belongs to the field of paper packaging container technology, specifically relating to a pressure-resistant paper tube with a rolled edge produced by a flat-rolling process. Background Technology

[0002] Paper tubes, as an environmentally friendly and recyclable packaging container, are widely used in the storage and transportation of tea, gifts, stationery, and chemical products. Currently, most paper tubes on the market are made using twill weave or spiral winding processes.

[0003] However, this spiral winding process creates continuous spiral seams inside and outside the paper tube. In actual use, especially when the paper tube needs to withstand vertical compressive loads from the top, the stress is easily concentrated along the seam line due to the relatively weak structural strength at the spiral seam. This can cause the top of the paper tube to "burst open" or crack longitudinally, significantly reducing the paper tube's compressive strength and durability. Summary of the Invention

[0004] In view of the technical problems mentioned in the background art, the purpose of this invention is to provide a compression-resistant paper tube with a roll end produced by a flat rolling process, so as to solve the technical problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a pressure-resistant paper tube with a rolled end using a flat rolling process, comprising a tube body. The tube body is integrally rolled from multiple layers of paper using a straight roll process, forming a cylindrical structure. The seam extends along the axial direction of the tube body. The upper opening edge of the tube body is provided with a flat rolling end, which is formed by rolling the paper edge inwards towards the inside of the tube body and flattening it, resulting in a U-shaped sandwich structure in cross-section.

[0006] The present invention has the following main advantages: By adopting a straight-tube process for integrated rolling, the paper fibers are continuously and evenly distributed throughout the circumference, and the seams extend along the axial direction of the tube, avoiding the structural weakness caused by the spiral seams in traditional spiral-wound paper tubes. When the paper tube is subjected to vertical pressure from the top, the stress can be evenly distributed to the entire tube wall, fundamentally solving the problem of "bursting" or longitudinal cracking caused by stress concentration in traditional paper tubes, and significantly improving the compressive strength and durability of the paper tube. By setting a flat-rolled opening at the upper edge of the tube, the paper is rolled inward from the edge and flattened to form a U-shaped sandwich structure, so that the upper edge of the tube forms a smooth arc transition, effectively dispersing the vertical pressure on the top of the tube, further enhancing the structural strength of the top of the tube, and at the same time avoiding the direct exposure of the paper edge to produce sharp burrs, thus improving the safety of use. By setting a reinforcing ring and a reinforcing bottom cover, the structural strength of the upper opening and bottom of the paper tube is further enhanced, effectively preventing the paper tube from deforming or cracking during long-term use or under pressure, and extending the service life of the paper tube. Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the cap and body cover structure of the present invention.

[0008] Figure 2 This is an exploded structural diagram of the cap and body of the present invention.

[0009] Figure 3 This is a schematic diagram of the cross-sectional structure of the cap and body of the present invention.

[0010] Figure 4 This is a schematic diagram of the cylindrical body and flat roll opening structure of the present invention.

[0011] Figure 5 This is a schematic diagram of the cap structure of the present invention.

[0012] Reference numerals: cylinder 10; flat rolled edge 20; inward rolled edge 21; flattened layer 22; placement chamber 11; chamber side wall 111; chamber bottom surface 112; cylinder cover 30; outer wall of cover 12; inner wall of cover 31; reinforcing ring 13; reinforcing bottom cover 14; first decorative wall 15; second decorative wall 32. Detailed Implementation

[0013] like Figures 1 to 5 As shown, a pressure-resistant paper tube with a flat-rolled opening includes a tube body 10. The tube body 10 is integrally rolled from multiple layers of paper using a straight-roll process, forming a cylindrical structure. Its seams extend along the axial direction of the tube body 10, avoiding the structural weakness caused by the spiral distribution of seams in traditional spiral winding processes. The upper opening edge of the tube body 10 is provided with a flat-rolled opening 20. The flat-rolled opening 20 is formed by rolling and flattening the paper edge inwards towards the inside of the tube body 10, creating a U-shaped sandwich structure in cross-section. This allows the upper edge of the tube body 10 to form a smooth arc transition, effectively dispersing the vertical pressure on the top of the tube body, enhancing the structural strength of the top of the tube body 10, preventing the top of the tube body 10 from bursting or cracking longitudinally under pressure, and improving the pressure resistance and durability of the paper tube.

[0014] In practical implementation, the flat roll opening 20 includes an inwardly rolled edge 21 and a flattening layer 22. The inwardly rolled edge 21 is formed by rolling the upper opening edge of the cylinder 10 inward, creating a rounded, curved structure at the paper edge and preventing the paper edge from being directly exposed and producing a sharp edge. The flattening layer 22 is formed by flattening the rolled paper edge against the upper wall of the cylinder 10, ensuring that the rolled paper adheres tightly to the upper wall of the cylinder 10, thus giving the flat roll opening 20 a U-shaped sandwich structure in cross-section. This U-shaped sandwich structure creates a smooth, rounded transition at the upper edge of the cylinder 10, effectively dispersing the vertical pressure on the top of the cylinder 10, enhancing the structural strength of the top of the cylinder 10, and preventing the top of the paper tube from bursting or cracking longitudinally under pressure. The flat roll opening 20 is integrally formed with the cylinder 10, requiring no additional adhesive reinforcement, simplifying the process.

[0015] In practice, the cylinder 10 is formed using a straight-cylinder process. This process involves winding multiple layers of paper straight along a direction parallel to the axis of the cylinder 10, ensuring the paper fibers align with the height of the cylinder 10, maintaining a consistent top and bottom diameter, and achieving uniform wall thickness. The cylinder 10 formed using this straight-cylinder process has no inclined spiral seams internally, and the paper fibers are continuously and evenly distributed throughout the circumference. When the paper cylinder is subjected to vertical pressure from the top, the stress is evenly distributed across the entire cylinder wall, preventing concentration at any single spiral seam. This fundamentally solves the problem of "bursting" or longitudinal cracking caused by stress concentration in traditional spiral-wound paper cylinders. Furthermore, the straight-cylinder process results in a smooth, flat surface without spiral protrusions, leading to a more even and vertical appearance, facilitating subsequent surface treatments such as printing and lamination.

[0016] In practice, the flat roll 20 at the upper opening of the tube 10 is manufactured using a specialized flat roll process. This process involves a rolling machine that horizontally rolls the edge of the paper at the opening of the tube 10 inwards, applying pressure to flatten and shape it. Through this process, the paper edge is evenly rolled and flattened, forming a U-shaped sandwich structure, resulting in a smooth, rounded edge at the top of the paper tube, free of sharp edges or burrs, and preventing cuts. Simultaneously, the flat roll process ensures a tight, secure bond between the rolled paper and the upper wall of the tube 10, preventing loosening and effectively enhancing the structural strength and compressive strength of the paper tube's opening. This flat roll process is simple to operate, highly efficient, suitable for mass production, and produces consistent and stable rolling quality, guaranteeing the dimensional accuracy and appearance consistency of the paper tube products.

[0017] In specific implementation, the interior of the cylinder 10 is provided with a placement chamber 11, which is a hollow cavity extending along the axial direction of the cylinder 10, used to accommodate and place items to be packaged. The inner side wall of the placement chamber 11 is provided with a chamber side wall 111, which is the inner wall surface of the cylinder 10 and is integrally formed with the cylinder 10. The surface is flat and smooth, which facilitates the insertion and removal of items. At the same time, it naturally transitions and connects with the flattening layer 22 of the flat roll opening 20. The inner bottom of the placement chamber 11 is provided with a chamber bottom surface 112, which is the closed end face of the bottom of the cylinder 10, used to support and bear the placed items, so that the items are placed stably in the paper tube and are not easy to shake.

[0018] In practical implementation, the upper end of the cylinder 10 is covered with a cylinder cover 30, and the outer wall of the upper end of the cylinder 10 is provided with a cover outer wall 12. The cover outer wall 12 is the surface of the outer wall of the upper end of the cylinder 10 and is used to cooperate with the cylinder cover 30 to close. The cylinder cover 30 is a circular cover structure and is placed on the upper opening of the cylinder 10 to close the placement chamber 11 and protect the internal items. The inner side wall of the cylinder cover 30 is provided with a cover inner wall 31. The inner diameter of the cover inner wall 31 is larger than the outer diameter of the cover outer wall 12, so that the cylinder cover 30 can be easily fitted onto the outer side of the upper end of the cylinder 10 to achieve a cover-close fit, making it convenient for users to open and close to put in and take out items.

[0019] In practice, the cylinder cover 30 is made of paper material, the same material as the cylinder body 10, both being environmentally friendly paper materials that are easy to recycle and meet environmental protection requirements. The cylinder cover 30 is integrally formed through die-cutting and stamping processes, resulting in high production efficiency and good dimensional accuracy. It fits tightly with the outer wall 12 of the cylinder body 10, ensuring a secure and stable fit that is not easily loosened. At the same time, it is easy to open, facilitating users to take out and put in items.

[0020] In practical implementation, a reinforcing ring 13 is fitted onto the upper outer wall of the cylinder 10. The reinforcing ring 13 is an annular structure, fitted onto the upper outer wall of the cylinder 10 to enhance the structural strength of the upper opening of the cylinder 10, preventing deformation or cracking of the upper edge of the paper tube during long-term use or under pressure. The reinforcing ring 13 is made of paper material and fits tightly against the upper outer wall of the cylinder 10, further improving the overall compressive strength and durability of the paper tube and extending its service life.

[0021] In practical implementation, the bottom of the tube 10 is provided with a reinforcing bottom cover 14. The reinforcing bottom cover 14 has a circular plate structure, is embedded in the bottom opening of the tube 10, and is pressed and fixed to the inner wall of the tube 10. The reinforcing bottom cover 14 is made of multi-layer composite cardboard, which has high structural strength and compression resistance, and can effectively bear the weight of the contents inside the tube, preventing the bottom from deforming or breaking under pressure. The reinforcing bottom cover 14 is integrally pressed with the bottom of the tube 10, the connection is firm and not easy to loosen, further improving the overall structural stability and durability of the paper tube.

[0022] In specific implementation, the outer peripheral wall of the tube 10 is provided with a first decorative wall 15. The first decorative wall 15 is a decorative layer covering the surface of the outer peripheral wall of the tube 10, used for printing, labeling or laminating. It can display patterns, text or brand logos according to customer needs, thereby improving the appearance and product display effect of the paper tube. The outer peripheral wall of the tube cover 30 is provided with a second decorative wall 32. The second decorative wall 32 is a decorative layer covering the surface of the outer peripheral wall of the tube cover 30, used for printing, labeling or laminating. It coordinates with the first decorative wall 15 to make the overall appearance of the paper tube uniform and beautiful, thereby enhancing the packaging grade and visual appeal of the product.

[0023] The manufacturing process of this invention includes the following steps:

[0024] Step 1: Straight Rolling. Multiple layers of paper are rolled straight along a direction parallel to the axis of the cylinder 10, ensuring the paper fibers align with the height of the cylinder 10. This produces a cylindrical body 10 with a uniform top and bottom diameter and wall thickness, with its seams extending axially.

[0025] Step 2: Flat roll opening. Using a rolling machine, the edge of the paper at the upper opening of the cylinder 10 is rolled inward in the horizontal direction to form an arc-shaped curled structure. Then, pressure is applied to flatten and shape the rolled paper edge onto the upper wall of the cylinder 10, forming a flat roll opening 20 with a U-shaped sandwich structure, making the upper edge of the cylinder 10 smooth and rounded without sharp edges or burrs.

[0026] Step 3: Bottom sealing. The reinforced bottom cover 14, made of multi-layer composite cardboard, is embedded in the bottom opening of the cylinder 10 and pressed and fixed to the inner wall of the cylinder 10, so that the bottom of the cylinder 10 forms a closed end face.

[0027] Step 4: Install the reinforcing ring. Place the annular reinforcing ring 13 onto the upper outer wall of the cylinder 10, ensuring a tight fit between it and the outer wall of the cylinder 10, thereby enhancing the structural strength of the opening at the upper end of the cylinder 10.

[0028] Step 5: Cap forming. The paper material is integrally formed into a circular cap 30 through die-cutting and stamping processes, so that the inner wall of the cap 30 forms the inner wall 31 of the cap.

[0029] Step Six: Exterior Decoration. A first decorative wall 15 is provided on the outer peripheral wall of the cylinder 10, and a second decorative wall 32 is provided on the outer peripheral wall of the cylinder cover 30. Patterns, text, or brand logos are displayed by printing, labeling, or lamination.

[0030] Step 7: Closing the packaging. Place the lid 30 on the upper outer wall of the tube body 10, so that the inner wall 31 of the lid fits and closes with the outer wall 12 of the lid, thus completing the packaging of the paper tube.

Claims

1. A compression-resistant paper tube with a rolled edge produced by a flat-winding process, characterized in that: It includes a cylindrical body (10), which is made of multiple layers of paper rolled together by a straight tube process, and has a cylindrical structure. Its seam extends along the axial direction of the cylindrical body (10). The upper opening edge of the cylindrical body (10) is provided with a flat roll opening (20). The flat roll opening (20) is formed by rolling the paper edge towards the inside of the cylindrical body (10) and flattening it. In cross-section, it has a U-shaped sandwich structure.

2. The compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 1, characterized in that: The flat roll opening (20) includes an inward rolled edge (21) and a flattening layer (22). The inward rolled edge (21) is formed by rolling the upper opening edge of the cylinder (10) inward. The flattening layer (22) is formed by pressing the rolled paper edge against the upper wall of the cylinder (10).

3. The compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 1, characterized in that: The interior of the cylinder (10) is provided with a placement chamber (11), which is a hollow cavity extending along the axial direction of the cylinder (10). The inner sidewall of the placement chamber (11) is provided with a chamber sidewall (111), and the inner bottom of the placement chamber (11) is provided with a chamber bottom surface (112).

4. A compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 1, characterized in that: The upper end of the cylinder (10) is covered with a cylinder cover (30), and the outer wall of the upper end of the cylinder (10) is provided with a cover outer wall (12). The cylinder cover (30) is a circular cover structure, and the inner wall of the cylinder cover (30) is provided with a cover inner wall (31). The inner diameter of the cover inner wall (31) is larger than the outer diameter of the cover outer wall (12).

5. A compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 4, characterized in that: The cylinder cover (30) is made of paper material and is integrally formed by die-cutting and stamping processes.

6. A compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 1, characterized in that: The upper outer wall of the cylinder (10) is fitted with a reinforcing ring (13), which is an annular ring structure and is made of paper material.

7. A compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 1, characterized in that: The bottom of the cylinder (10) is provided with a reinforced bottom cover (14). The reinforced bottom cover (14) is a circular plate structure, which is embedded in the bottom opening of the cylinder (10) and pressed and fixed with the inner wall of the cylinder (10). The reinforced bottom cover (14) is made of multi-layer composite paperboard.

8. A compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 1, characterized in that: The outer peripheral wall of the cylinder (10) is provided with a first decorative wall (15).

9. A compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 4, characterized in that: The outer peripheral wall of the cylinder cover (30) is provided with a second decorative wall (32).

10. A compression-resistant paper tube with a rolled edge produced by a flat-winding process according to claim 1, characterized in that: The flat roll opening (20) is integrally formed with the cylinder (10).

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