A winding film winding drum
By designing a telescopic winding cylinder and a ribbed positioning step structure, the problem of limited applicability of the winding machine was solved, achieving stable fixation and enhanced applicability for film tubes of different diameters and widths.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- DONGGUAN ZHITENG PLASTIC PROD CO LTD
- Filing Date
- 2025-07-22
- Publication Date
- 2026-07-10
AI Technical Summary
Existing winding equipment cannot be used with film tubes of different widths and diameters, resulting in limited applicability.
A first and second cylinder with telescopic connection were designed. By setting ribs and positioning step structures on the cylinder, it can adapt to winding film rolls of different diameters and adapt to winding film of different widths by adjusting the cylinder insertion amount.
It achieves stable fixation of stretch film rolls with different diameters and widths, enhances connection stability, prevents slippage, and improves applicability.
Smart Images
Figure CN224477776U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of film winding equipment, and in particular to a film winding cylinder. Background Technology
[0002] With the continuous development of society and economy and the continuous improvement of people's living standards, more and more tools are being manufactured and widely used in agriculture, industry and service industries. Tools come in a wide variety of types, and have been further innovated according to different needs, playing an indispensable role in people's work and life, and providing convenience for their work and life.
[0003] In the product manufacturing process, packaging is usually involved. In existing technology, wrapping equipment is generally used to wrap the product with film. The wrapping equipment is equipped with a wrapper for fixing the film tube. This wrapper is generally a fixed tube structure. When in use, the film tube is installed on the fixed tube, and then the item is wrapped. This type of wrapper is generally a single straight tube. Its length cannot be adjusted after manufacturing. It can only be used for film tubes of a certain width, which means it cannot be used for film tubes of different widths. In addition, its diameter is uniform, which means it can only be used for film tubes of a certain diameter, which means it cannot be used for film tubes of different diameters.
[0004] Therefore, a new technology needs to be developed to solve the above problems. Utility Model Content
[0005] In view of this, the present invention addresses the deficiencies of the existing technology, and its main objective is to provide a stretch film winding cylinder that is applicable to stretch films of different widths and to stretch film rolls of different diameters, thereby improving its applicability.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] A stretch film wrapping cylinder includes a first cylinder and a second cylinder that are telescopically connected; one end of the first cylinder can be detachably inserted into one end of the second cylinder.
[0008] The other end of the first cylinder is provided with a first annular stop. On the outer peripheral sidewall of the other end of the first cylinder, near the first annular stop, a plurality of first protruding ribs are provided. The plurality of first protruding ribs are arranged at intervals along the circumferential direction of the first cylinder. The first protruding ribs extend along the axial direction of the first cylinder. The first protruding ribs have a first positioning step and a second positioning step connected in sequence. The first positioning step and the second positioning step are arranged to decrease in height towards the second cylinder.
[0009] The other end of the second cylinder is provided with a second annular stop. On the outer peripheral sidewall of the other end of the second cylinder, near the second annular stop, a plurality of second protruding ribs are provided. The plurality of second protruding ribs are arranged at intervals along the circumferential direction of the second cylinder. The second protruding ribs extend along the axial direction of the second cylinder. The second protruding ribs have a third positioning step and a fourth positioning step connected in sequence. The third positioning step and the fourth positioning step are arranged to decrease in height toward the first cylinder in sequence.
[0010] As a preferred embodiment, one end of the first rib extends to the side of the first annular stop facing the second cylinder, and the first positioning step and the second positioning step are formed on the side of the first rib away from the outer peripheral sidewall of the first cylinder; the side of the first positioning step near the first annular stop has a first limiting protrusion extending outward on one end of the first rib.
[0011] As a preferred embodiment, one end of the second rib extends to the side of the second annular stop facing the first cylinder, and the third positioning step and the fourth positioning step are formed on the side of the second rib away from the outer peripheral sidewall of the second cylinder; the side of the third positioning step near the second annular stop has a second limiting protrusion extending outward on one end of the second rib.
[0012] As a preferred embodiment, the side of the first positioning step away from the first cylinder is a first inclined surface, and the side of the second positioning step away from the first cylinder is a second inclined surface. Both the first and second inclined surfaces are inclined inward toward the second cylinder.
[0013] As a preferred embodiment, the side of the third positioning step away from the second cylinder is a third inclined surface, and the side of the fourth positioning step away from the second cylinder is a fourth inclined surface. Both the third and fourth inclined surfaces are inclined inward toward the first cylinder.
[0014] As a preferred embodiment, a plurality of first through grooves are provided on the outer peripheral sidewall of the first cylinder, and the plurality of first through grooves are arranged at intervals along the axial direction of the first cylinder, and the first through grooves penetrate the inner and outer sides of the first cylinder.
[0015] As a preferred embodiment, a plurality of second through grooves are provided on the outer peripheral sidewall of the second cylinder, and the plurality of second through grooves are arranged sequentially at intervals along the axial direction of the second cylinder, and the second through grooves penetrate the inner and outer sides of the second cylinder.
[0016] As a preferred embodiment, a trumpet-shaped first guide cavity is formed at the other end of the first cylinder.
[0017] As a preferred embodiment, a trumpet-shaped second guide cavity is formed inside the other end of the second cylinder.
[0018] As a preferred embodiment, the inner circumferential sidewall of one end of the second cylinder is provided with a plurality of arc-shaped limiting protrusions. The plurality of arc-shaped limiting protrusions are located on one side near the opening of the second cylinder facing the first cylinder. The plurality of arc-shaped limiting protrusions are arranged sequentially at intervals along the axial direction of the second cylinder. The arc-shaped limiting protrusions extend along the circumferential direction of the second cylinder. As the first cylinder is inserted relative to the second cylinder, the outer circumferential sidewall of the first cylinder comes into frictional contact with the arc-shaped limiting protrusions.
[0019] This utility model has significant advantages and beneficial effects compared with the prior art. Specifically, as can be seen from the above technical solution, it mainly involves providing a plurality of first protruding ribs on the outer peripheral sidewall of the other end of the first cylinder, allowing the first protruding ribs to extend along the axial direction of the first cylinder, and having a first positioning step and a second positioning step connected in sequence. The first positioning step and the second positioning step are arranged to decrease in height towards the second cylinder. Similarly, a plurality of second protruding ribs are provided on the outer peripheral sidewall of the other end of the second cylinder, allowing the second protruding ribs to extend along the axial direction of the second cylinder, and having a third positioning step and a fourth positioning step connected in sequence. The first and fourth positioning steps are set to decrease in height towards the first cylinder in sequence. In this way, the combination design of the first, second, third, and fourth positioning steps can make the stretch film rolls of different diameters firmly fixed at the different positioning steps of the ribs, so that it can be used for stretch film rolls of different diameters. The ribs can also effectively increase the friction between the stretch film rolls and the first and second cylinders, enhance the stability of the connection between the stretch film rolls and the first and second cylinders, and make the stretch film rolls less likely to slip relative to the first and second cylinders, so that the stretch film rolls can be well fixed on the first and second cylinders.
[0020] Furthermore, by including a telescopically connected first and second cylinder, one end of the first cylinder can be detachably inserted into one end of the second cylinder. Thus, by adjusting the insertion amount of the first cylinder into the second cylinder, the length of the entire winding cylinder can be changed to accommodate winding films of different widths, thereby improving applicability.
[0021] To more clearly illustrate the structural features, technical means, and specific objectives and functions of this utility model, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description
[0022] Figure 1 This is a three-dimensional schematic diagram of the overall structure of an embodiment of this utility model;
[0023] Figure 2 This is a schematic plan view of the overall structure of an embodiment of this utility model;
[0024] Figure 3 This is another planar schematic diagram of the overall structure of an embodiment of this utility model;
[0025] Figure 4 This is a cross-sectional schematic diagram of an embodiment of the present utility model;
[0026] Figure 5 This is another cross-sectional schematic diagram of an embodiment of the present utility model;
[0027] Figure 6 This is an exploded view of an embodiment of the present utility model;
[0028] Figure 7 This is another exploded view of an embodiment of the present invention.
[0029] Explanation of reference numerals in the attached diagram:
[0030] 10. First cylinder body; 11. Contact protrusion
[0031] 111, protrusion; 12, first annular stop.
[0032] 13. First protruding rib 131. First positioning step
[0033] 132. Second positioning step; 133. First limiting protrusion
[0034] 14. First through slot; 15. First guide cavity
[0035] 20. Second cylinder body; 21. Second annular stop section
[0036] 22. Second protruding rib; 221. Third positioning step
[0037] 222. Fourth positioning step; 223. Second limiting protrusion
[0038] 23. Arc-shaped limiting protrusion 24. Limiting groove
[0039] 25. Second through slot; 26. Second guide cavity. Detailed Implementation
[0040] In the description of this utility model, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "inner", and "outer" appear to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0041] Please refer to Figures 1 to 7 As shown, it illustrates the specific structure of the stretch film winding tube provided in the embodiment of the present invention. It is mainly used in boneless (i.e., paperless) stretch film, but is not limited to the application of boneless stretch film.
[0042] The stretch film wrapping cylinder includes a telescopically connected first cylinder 10 and second cylinder 20; both the first cylinder 10 and the second cylinder 20 are hollow straight cylinders, and both the first cylinder 10 and the second cylinder 20 are made of plastic; one end of the first cylinder 10 can be detachably inserted into one end of the second cylinder 20, so that the length of the entire wrapping cylinder can be changed by adjusting the insertion amount of the first cylinder 10 into the second cylinder 20 to suit wrapping films of different widths.
[0043] The other end of the first cylindrical body 10 is provided with a first annular stop portion 12. On the outer peripheral sidewall of the other end of the first cylindrical body 10, near the first annular stop portion 12, a plurality of first protruding ribs 13 are provided. These first protruding ribs 13 are arranged at intervals along the circumferential direction of the first cylindrical body 10. The first protruding ribs 13 extend along the axial direction of the first cylindrical body 10 and have sequentially connected first positioning steps 131 and second positioning steps 132. The first positioning steps 131 and second positioning steps 132 are arranged with decreasing heights towards the second cylindrical body 20. The other end of the second cylindrical body 20 is provided with a second annular stop portion 21. On the outer peripheral sidewall of the other end of the second cylindrical body 20, near the second annular stop portion 21, a plurality of second protruding ribs 22 are provided. These second protruding ribs 22 are arranged at intervals along the circumferential direction of the second cylindrical body 20. The second protruding ribs 22 extend along the axial direction of the second cylindrical body 20. The second rib 22 has a third positioning step 221 and a fourth positioning step 222 connected in sequence. The third positioning step 221 and the fourth positioning step 222 are arranged to decrease in height towards the first cylinder 10. The first rib 13 is arranged correspondingly to the second rib 22. Thus, through the combined design of the first positioning step 131, the second positioning step 132 and the third positioning step 221, the fourth positioning step 222, different diameters of the stretch film rolls can be stably fixed at different positioning steps of the ribs, so that it can be used for stretch film rolls of different diameters. Moreover, the ribs can effectively increase the friction between the stretch film rolls and the first cylinder 10 and the second cylinder 20, enhance the stability of the connection between the stretch film rolls and the first cylinder 10 and the second cylinder 20, and make it less likely for the stretch film rolls to slip relative to the first cylinder 10 and the second cylinder 20, so that the stretch film rolls can be well fixed on the first cylinder 10 and the second cylinder 20.
[0044] One end of the first rib 13 extends to the side of the first annular stop 12 facing the second cylinder 20. The first positioning step 131 and the second positioning step 132 are formed on the side of the first rib 13 away from the outer peripheral sidewall of the first cylinder 10. A first limiting protrusion 133 extending outward is formed on one end of the first rib 13 near the first annular stop 12. One end of the second rib 22 extends to the side of the second annular stop 21 facing the first cylinder 10. The third positioning step 221 and the fourth positioning step 222 are formed on the side of the second rib 22 away from the outer peripheral sidewall of the first cylinder 10. On one side of the outer peripheral wall of the second cylinder 20; the third positioning step 221 near the second annular stop 21 has a second limiting protrusion 223 extending outward on one end of the second protruding rib 22; the first limiting protrusion 133 and the second limiting protrusion 223 are correspondingly arranged; here, through the combined design of the first limiting protrusion 133 and the second limiting protrusion 223, when the stretch film roll is fixed on the cylinder, a gap is left between the side of the stretch film roll and the annular stop, thereby avoiding the stretch film roll from directly contacting the annular stop, so as to reduce the wear of the stretch film roll by the annular stop during rotation.
[0045] The first positioning step 131 has a first inclined surface on the side away from the first cylinder 10, and the second positioning step 132 has a second inclined surface on the side away from the first cylinder 10. Both the first and second inclined surfaces are inclined inward toward the second cylinder 20. The third positioning step 221 has a third inclined surface on the side away from the second cylinder 20, and the fourth positioning step 222 has a fourth inclined surface on the side away from the second cylinder 20. Both the third and fourth inclined surfaces are inclined inward toward the first cylinder 10. This combination of the first, second, third, and fourth inclined surfaces allows the stretch film roll to be more smoothly fixed on the corresponding positioning steps.
[0046] The outer peripheral sidewall of the first cylinder 10 is provided with a plurality of first through grooves 14, which are arranged sequentially at intervals along the axial direction of the first cylinder 10. The first through grooves 14 penetrate the inner and outer sides of the first cylinder 10, and the first through grooves 14 are symmetrically arranged on two opposite sides of the outer peripheral sidewall of the first cylinder 10. The outer peripheral sidewall of the second cylinder 20 is provided with a plurality of second through grooves 25, which are arranged sequentially at intervals along the axial direction of the second cylinder 20. The second through grooves 25 penetrate the inner and outer sides of the second cylinder 20, and the second through grooves 25 are symmetrically arranged on two opposite sides of the outer peripheral sidewall of the second cylinder 20. Both the first through grooves 14 and the second through grooves 25 are elliptical. In this way, the material usage of the cylinder and the weight of the cylinder can be reduced by the combined design of the first through grooves 14 and the second through grooves 25.
[0047] A trumpet-shaped first guide cavity 15 is formed inside the other end of the first cylinder 10. The first guide cavity 15 gradually decreases in size from left to right, and its axis coincides with the axis of the inner cavity of the first cylinder 10. A trumpet-shaped second guide cavity 26 is formed inside the other end of the second cylinder 20. The second guide cavity 26 gradually decreases in size from right to left, and its axis coincides with the axis of the inner cavity of the second cylinder 20. Through the combined design of the first guide cavity 15 and the second guide cavity 26, the insertion of the external tubular structure into the first cylinder 10 and the second cylinder 20 can be smoother. When the first cylinder 10 is inserted into the second cylinder 20, the axes of the first guide cavity 15 and the second guide cavity 26 coincide. In addition, the cross-section of the inner peripheral sidewall at the opening of the first guide cavity 15 and the second guide cavity 26 is arc-shaped, which is more conducive to the introduction of the external tubular structure.
[0048] The inner circumferential sidewall of one end of the second cylinder 20 is provided with a plurality of arc-shaped limiting protrusions 23. The plurality of arc-shaped limiting protrusions 23 are located on one side near the opening of the second cylinder 20 facing the first cylinder 10. The plurality of arc-shaped limiting protrusions 23 are arranged at intervals along the axial direction of the second cylinder 20. The arc-shaped limiting protrusions 23 extend along the circumferential direction of the second cylinder 20. As the first cylinder 10 is inserted relative to the second cylinder 20, the outer circumferential sidewall of the first cylinder 10 comes into frictional contact with the arc-shaped limiting protrusions 23.
[0049] A plurality of contact protrusions 11 are provided on the outer peripheral sidewall of one end of the first cylinder 10. The plurality of contact protrusions 11 are arranged at intervals along the axial direction of the first cylinder 10 and extend along the circumferential direction of the first cylinder 10. As the first cylinder 10 is inserted relative to the second cylinder 20, the contact protrusions 11 rub against the inner peripheral sidewall of the second cylinder 20. In this way, by setting the contact protrusions 11, after the first cylinder 10 is inserted into the second cylinder 20, it can rub against the inner peripheral sidewall of the second cylinder 20 through the multiple contact protrusions 11, thereby effectively increasing the friction between the first cylinder 10 and the second cylinder 20, enhancing the stability of the connection between the first cylinder 10 and the second cylinder 20, making it less likely for the first cylinder 10 and the second cylinder 20 to slide relative to each other, so as to ensure that the insertion amount of the first cylinder 10 into the second cylinder 20 is not easily changed, and the first cylinder 10 can be well fixed on the second cylinder 20, thereby ensuring the smooth operation of the winding operation and bringing convenience to production.
[0050] Preferably, a plurality of contact protrusions 11 are arranged at uniform intervals along the axial direction of the first cylindrical body 10, so that the insertion depth of the first cylindrical body 10 into the second cylindrical body 20 can be accurately determined based on the number of contact protrusions 11 inserted into the second cylindrical body 20. In this embodiment, the contact protrusion 11 includes a plurality of protrusions 111, and the side of the protrusion 111 away from the outer peripheral sidewall of the first cylindrical body 10 is provided with a contact surface, which is used to contact the inner peripheral sidewall of the second cylindrical body 20; the plurality of protrusions 111 are arranged at intervals along the circumferential direction of the first cylindrical body 10; in addition, the plurality of protrusions 111 of the plurality of contact protrusions 11 are arranged in a matrix, which not only makes the appearance more beautiful, but also facilitates molding and manufacturing.
[0051] Preferably, in this embodiment, the minimum outer diameter of the first cylinder 10 is smaller than the inner diameter of the second cylinder 20, and the maximum outer diameter of the first cylinder 10 at the contact protrusion 11 is larger than the inner diameter of the second cylinder 20. Thus, when the first cylinder 10 is inserted into or pulled out of the second cylinder 20, since both the first cylinder 10 and the second cylinder 20 are made of plastic and have a certain elastic deformation, the contact protrusion 11 can squeeze the inner peripheral sidewall of the second cylinder 20. Under the compression of the contact protrusion 11, the inner peripheral sidewall of the second cylinder 20 elastically deforms, allowing the first cylinder 10 to be smoothly inserted and pulled out. When the first cylinder 10 is inserted or pulled out a certain amount and stops being inserted or pulled out, the inner peripheral sidewall of the second cylinder 20 can recover a certain deformation and squeeze the contact protrusion 11 to make contact, so that the first cylinder 10 is well fixed on the second cylinder 20.
[0052] Two contact protrusions 11 are arranged between two adjacent first through slots 14 in the axial direction of the first cylinder 10 so that the first through slots 14 are arranged at equal intervals, and some protrusions 111 surround the corresponding first through slots 14. In this embodiment, the leftmost first through slot 14 is close to the side of the first rib 13 away from the first annular stop 12, and protrusions 111 are provided on the left side of the leftmost first through slot 14 and on both sides along the circumferential direction of the first cylinder 10.
[0053] In this embodiment, a limiting groove 24 is formed between two adjacent arc-shaped limiting protrusions 23; as the first cylinder 10 is inserted relative to the second cylinder 20, the corresponding contact protrusion 11 is located in the corresponding limiting groove 24, so as to further enhance the stability of the connection between the first cylinder 10 and the second cylinder 20 through the mutual limiting between the arc-shaped limiting protrusions 23 and the contact protrusions 11, so that the first cylinder 10 and the second cylinder 20 are not easy to slide relative to each other, so as to ensure that the first cylinder 10 is not easily moved after adjusting the insertion amount of the first cylinder 10 into the second cylinder 20, and the first cylinder 10 can be well fixed on the second cylinder 20.
[0054] Preferably, a plurality of arc-shaped limiting protrusions 23 are symmetrically arranged on two opposite sides of the inner peripheral sidewall at one end of the second cylinder 20. This allows the contact protrusions 11 on two opposite sides of the outer peripheral sidewall of the first cylinder 10 to be simultaneously limited, which is more conducive to the stable connection between the first cylinder 10 and the second cylinder 20.
[0055] In summary, the key design feature of this utility model lies in the following: Several first protruding ribs are provided on the outer peripheral sidewall of the other end of the first cylinder, extending along the axial direction of the first cylinder. Each first protruding rib has a first positioning step and a second positioning step connected in sequence, with the first and second positioning steps decreasing in height towards the second cylinder. Similarly, several second protruding ribs are provided on the outer peripheral sidewall of the other end of the second cylinder, extending along the axial direction of the second cylinder. Each second protruding rib has a third positioning step and a fourth positioning step connected in sequence, with the third and fourth positioning steps decreasing in height towards the first cylinder. Thus, through the combined design of the first, second, third, and fourth positioning steps, different... The stretch film rolls of different diameters are securely fixed at different positioning steps of the ribs, making them suitable for stretch film rolls of different diameters. The ribs effectively increase the friction between the stretch film roll and the first and second cylinders, enhancing the stability of the connection between the stretch film roll and the first and second cylinders. This prevents the stretch film roll from slipping relative to the first and second cylinders, ensuring that the stretch film roll is well fixed to the first and second cylinders. Furthermore, by including the telescopically connected first and second cylinders, one end of the first cylinder can be detachably inserted into one end of the second cylinder. Thus, by adjusting the insertion depth of the first cylinder into the second cylinder, the length of the entire stretch roll can be changed to accommodate stretch films of different widths, improving its applicability.
[0056] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the technical scope of the present utility model. Therefore, any minor modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the scope of the technical solution of the present utility model.
Claims
1. A stretch film winding cylinder, characterized in that: It includes a first cylinder and a second cylinder that are telescopically connected; one end of the first cylinder can be detachably inserted into one end of the second cylinder; The other end of the first cylinder is provided with a first annular stop. On the outer peripheral sidewall of the other end of the first cylinder, near the first annular stop, a plurality of first protruding ribs are provided. The plurality of first protruding ribs are arranged at intervals along the circumferential direction of the first cylinder. The first protruding ribs extend along the axial direction of the first cylinder. The first protruding ribs have a first positioning step and a second positioning step connected in sequence. The first positioning step and the second positioning step are arranged to decrease in height towards the second cylinder. The other end of the second cylinder is provided with a second annular stop. On the outer peripheral sidewall of the other end of the second cylinder, near the second annular stop, a plurality of second protruding ribs are provided. The plurality of second protruding ribs are arranged at intervals along the circumferential direction of the second cylinder. The second protruding ribs extend along the axial direction of the second cylinder. The second protruding ribs have a third positioning step and a fourth positioning step connected in sequence. The third positioning step and the fourth positioning step are arranged to decrease in height toward the first cylinder in sequence.
2. The film winding cylinder according to claim 1, characterized in that: One end of the first rib extends to the side of the first annular stop facing the second cylinder. The first positioning step and the second positioning step are formed on the side of the first rib away from the outer peripheral sidewall of the first cylinder. The side of the first positioning step near the first annular stop has a first limiting protrusion extending outward on one end of the first rib.
3. The film winding cylinder according to claim 1, characterized in that: One end of the second rib extends to the side of the second annular stop facing the first cylinder. The third positioning step and the fourth positioning step are formed on the side of the second rib away from the outer peripheral sidewall of the second cylinder. The side of the third positioning step near the second annular stop has a second limiting protrusion extending outward on one end of the second rib.
4. The film winding cylinder according to claim 1, characterized in that: The side of the first positioning step away from the first cylinder is the first inclined surface, and the side of the second positioning step away from the first cylinder is the second inclined surface. Both the first and second inclined surfaces are inclined inward toward the second cylinder.
5. A film winding cylinder according to claim 1, characterized in that: The side of the third positioning step away from the second cylinder is the third inclined surface, and the side of the fourth positioning step away from the second cylinder is the fourth inclined surface. Both the third and fourth inclined surfaces are inclined inward toward the first cylinder.
6. A film winding cylinder according to claim 1, characterized in that: The outer peripheral sidewall of the first cylinder is provided with a plurality of first through grooves, which are arranged at intervals along the axial direction of the first cylinder and penetrate the inner and outer sides of the first cylinder.
7. A film winding cylinder according to claim 1, characterized in that: The outer peripheral sidewall of the second cylinder is provided with a plurality of second through grooves, which are arranged at intervals along the axial direction of the second cylinder and penetrate the inner and outer sides of the second cylinder.
8. A film winding cylinder according to claim 1, characterized in that: A trumpet-shaped first guide cavity is formed inside the other end of the first cylinder.
9. A film winding cylinder according to claim 1, characterized in that: A trumpet-shaped second guide cavity is formed inside the other end of the second cylinder.
10. A film winding cylinder according to claim 1, characterized in that: The inner circumferential sidewall of one end of the second cylinder is provided with a plurality of arc-shaped limiting protrusions. The plurality of arc-shaped limiting protrusions are located on one side near the opening of the second cylinder facing the first cylinder. The plurality of arc-shaped limiting protrusions are arranged at intervals along the axial direction of the second cylinder. The arc-shaped limiting protrusions extend along the circumferential direction of the second cylinder. As the first cylinder is inserted relative to the second cylinder, the outer circumferential sidewall of the first cylinder comes into frictional contact with the arc-shaped limiting protrusions.