Lightweight disc wheel reinforcing structure and manufacturing method

Abstract

The invention provides a light-weight disc wheel reinforcing structure which comprises a rim and side covers arranged at the two ends of the rim, hub mounting parts are arranged in the middles of the side covers at the two ends, a plurality of strip-shaped reinforcing parts arranged along the hub mounting parts in an annular array mode are arranged between the side covers at the two ends, and each strip-shaped reinforcing part comprises a reinforcing part body. The extension parts are arranged at the two ends of the reinforcing part body and used for being connected with a side cover, and the thickness of the strip-shaped reinforcing part is 0.2-0.4 mm. By arranging the strip-shaped reinforcing parts with the thickness of only 0.2-0.4 mm, the rigidity of the disc wheel can be improved, better stability can be provided, compared with the situation that left and right independent side covers need more than 6 layers of carbon fibers, the advantages can be achieved under the condition that the number of layers of the carbon fibers of the left and right side covers is reduced to 4, the overall weight of the disc wheel is remarkably reduced, and the service life of the disc wheel is prolonged. And meanwhile, the extension part and the side cover are connected by adopting a hot press molding process, so that the aging problem of a traditional epoxy resin adhesive is avoided, the long-term stability of the structure is improved, and the impact resistance is also improved.

Description

Technical Field

[0001] The invention relates to a lightweight disc wheel reinforcement structure and a manufacturing method thereof, and is applied to the field of bicycle wheel rim manufacturing. Background Art

[0002] Disc wheels are used in cycling time trials and track cycling races due to their unique aerodynamic advantages.

[0003] The current mainstream disc wheel reinforcement structure is a new type of carbon fiber disc wheel with a patent number of CN221187961U. The patent discloses that the reinforcing rib assembly includes two ribs and a connecting piece, the two ribs are respectively fixed to the inner side surfaces of the two discs, the connecting piece is provided with a connecting groove corresponding to the two ribs, the connecting piece is respectively engaged and fixed with the two ribs through the connecting groove and connected and fixed with the inner side surfaces of the two discs, but this structure has two major problems.

[0004] 1. Adhesives such as epoxy resin will gradually age under ultraviolet light, moisture and temperature cycles, resulting in a decrease in bonding strength. Some carbon fiber rims have debonded edges after a long period of time and need to be returned to the factory for rebonding. In addition, their impact resistance is also reduced.

[0005] 2. The ribs include internal foam plastic and a carbon fiber layer wrapped around the outer periphery of the foam plastic, which makes the disc wheel thicker, and thus causes the overall weight of the disc wheel to be heavier, reducing riding efficiency and affecting riding experience.

[0006] In view of the above problems, the present invention studies a lightweight disc wheel reinforcement structure and a manufacturing method. Summary of the invention

[0007] The present invention provides a lightweight disc wheel reinforcement structure and a manufacturing method, which can effectively solve the above-mentioned problems.

[0008] The present invention is achieved in that:

[0009] A lightweight disc wheel reinforcement structure, comprising:

[0010] A wheel rim and side covers arranged at both ends of the wheel rim, a hub mounting portion is arranged in the middle of the side covers at both ends, and a plurality of strip reinforcement portions arranged in a circular array along the hub mounting portion are arranged between the side covers at both ends. The strip reinforcement portion includes a reinforcement portion body and extension portions arranged at both ends of the reinforcement portion body, the extension portions are connected to the side covers by hot pressing, and the thickness of the strip reinforcement portion is 0.2 to 0.4 mm.

[0011] As a further improvement, the reinforcement part body is a two-layer thin sheet structure that fits together, and the extension part is folded toward both sides from the ends of the thin sheet structure and fits on the inner wall of the side cover.

[0012] As a further improvement, the number of the strip-shaped reinforcement parts is 3 to 8.

[0013] As a further improvement, the side cover is a double-layer structure, the inside of the side cover is filled with PMI material, and the thickness of the side cover is 1.6-2.0 mm.

[0014] As a further improvement, the wheel rim is formed by fusing 3 to 5 layers of carbon fiber structure.

[0015] A method for manufacturing a lightweight disc wheel reinforcement structure comprises the following steps:

[0016] S1: placing the bottom side cover preform, the hub mounting part preform and the wheel rim preform on the lower mold;

[0017] S2: Fold the bottom end extension of the preset strip reinforcement portion to both sides and place it on the bottom side cover preform;

[0018] S3: setting the wheel rim shaping mold on the outer periphery of the wheel rim preform, placing the special-shaped three-dimensional airbag group on the side cover preform, and the special-shaped three-dimensional airbag group limits the strip reinforcement part;

[0019] S4: Fold the other end extension of the strip reinforcement portion to both sides and place it close to the special-shaped three-dimensional airbag assembly;

[0020] S5: placing the upper side cover preform on the anisotropic three-dimensional airbag, buckling the upper mold and the lower mold to form a disc wheel preform mold, and inflating the anisotropic three-dimensional airbag group;

[0021] S6: placing the disc wheel preform mold in a mold heating box, heating and shaping, cooling and forming, and removing the special-shaped three-dimensional air bag assembly to form a bicycle disc wheel finished product.

[0022] As a further improvement, the wheel rim preform includes a layer of inner disc wheel preform, a layer of outer disc wheel preform, and several layers of middle disc wheel preforms stacked between the inner disc wheel preform and the outer disc wheel preform, and the lower ends of the inner disc wheel preform and the outer disc wheel preform clamp and fix the bottom side cover preform.

[0023] As a further improvement, the upper end of the inner disc wheel preform is folded inward in a horizontal direction, the upper end of the outer disc wheel preform is arranged in a vertical direction, the upper side cover preform is placed on the special-shaped three-dimensional airbag group close to the upper end of the inner disc wheel preform, and the outer disc wheel preform is folded downward and close to the upper side cover preform.

[0024] As a further improvement, the special-shaped three-dimensional air bag group includes a plurality of air bags corresponding to the strip-shaped reinforcement parts, and a plurality of avoidance openings corresponding to the strip-shaped reinforcement parts are arranged in a ring array between adjacent air bags with the hub mounting part preform as the axis, and the avoidance openings avoid and give way to the strip-shaped reinforcement parts.

[0025] As a further improvement, the curing temperature of the mold heating and shaping is 160-200°C, the curing time is 30-40 minutes, and the heating rate is 7-10°C / min.

[0026] The beneficial effects of the present invention are:

[0027] (1) By providing a strip reinforcement portion with a thickness of only 0.2 to 0.4 mm, not only can the rigidity of the disc wheel be improved, better stability be provided, and athletes can achieve better results, but also, compared with the left and right independent side covers which require more than 6 layers of carbon fiber to achieve a stable effect, the present invention can achieve the above advantages while reducing the number of carbon fiber layers of the left and right side covers to 4 layers, significantly reducing the overall weight of the disc wheel. At the same time, a hot pressing molding process is used to connect the extension portion and the side cover, avoiding the aging problem of traditional epoxy resin adhesives, improving the long-term stability of the structure, and also improving the impact resistance.

[0028] (2) The bottom end extension of the preset strip reinforcement part is folded to both sides and placed on the bottom side cover preform, and then the special-shaped three-dimensional airbag group is placed on the side cover preform. The special-shaped three-dimensional airbag group limits the strip reinforcement part, and the other end extension of the wheel rim strip reinforcement part is folded to both sides and pressed against the special-shaped three-dimensional airbag group. After the mold is closed, the special-shaped three-dimensional airbag group is inflated and finally placed in the mold heating box for hot pressing. The advantage of this arrangement is that since the strip reinforcement part is thin, it may bend or twist during the molding process. The irregular strip reinforcement part may cause the center of gravity of the entire wheel rim to deviate during use, which will affect the riding experience. Therefore, the wheel rim made by this method has better stability and can effectively improve the riding performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 It is a schematic diagram of the side structure provided by an embodiment of the present invention.

[0031] Figure 2 yes Figure 1 Schematic diagram of the cross-sectional structure at AA in the middle.

[0032] Figure 3 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 1 .

[0033] Figure 4 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 1 Cross-sectional view of .

[0034] Figure 5 yes Figure 4 Schematic diagram of the enlarged structure at point C in the middle.

[0035] Figure 6 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 2 .

[0036] Figure 7 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 3 .

[0037] Figure 8 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 4 .

[0038] Fig. 9 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 5 .

[0039] Fig.10 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 6 .

[0040] Fig.11 The present invention provides a method for manufacturing a lightweight disc wheel reinforcement structure. Figure 7 .

[0041] Fig.12 It is a schematic diagram comparing the stress analysis results in the finite element analysis of the comparative example and the embodiment of the present invention.

[0042] Fig.13 It is a schematic diagram comparing the strain analysis results in the finite element analysis of the comparative example and the embodiment of the present invention.

[0043] Fig.14 It is a schematic diagram comparing the displacement analysis results in the finite element analysis of the comparative example and the embodiment of the present invention.

[0044] The accompanying drawings are as follows:

[0045] 10. Wheel rims;

[0046] 20. Side cover;

[0047] 30. Hub mounting part;

[0048] 40. Strip reinforcement portion; 41. Reinforcement portion body; 42. Extension portion;

[0049] 50. Side cover preform; 51. Hub mounting part preform; 52. Rim preform; 521. Internal disc wheel preform; 522. External disc wheel preform; 523. Middle disc wheel preform;

[0050] 60. Lower mold; 61. Special-shaped three-dimensional air bag group; 611. Air bag; 62. Wheel rim shaping mold; 63. Upper mold; 64. Mold heating box. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0052] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0053] Reference Figures 1-2 As shown, a lightweight disc wheel reinforcement structure includes:

[0054] The wheel rim 10 and the side covers 20 arranged at both ends of the wheel rim 10, the middle parts of the side covers 20 at both ends are provided with hub mounting parts 30, and a plurality of strip reinforcement parts 40 arranged in a circular array along the hub mounting parts 30 are provided between the side covers 20 at both ends. The strip reinforcement part 40 includes a reinforcement part body 41 and extension parts 42 arranged at both ends of the reinforcement part body 41, and the extension parts 42 are connected to the side covers 20 by hot pressing. The thickness of the strip reinforcement part 40 is 0.2-0.4 mm. In the present embodiment, the thickness of the strip reinforcement part 40 is 0.2 mm, which can significantly reduce the overall weight of the disc wheel.

[0055] In this embodiment, the reinforcement body 41 is a two-layer thin sheet structure that fits together, and the extension part 42 is folded from the ends of the thin sheet structure to both sides and fits on the inner wall of the side cover 20. The double-layer thin sheet structure fit design increases the contact area between the reinforcement and the side cover, and the folded and fitted ends further improve the connection strength and anti-peeling ability, reduce the risk of debonding due to vibration or impact, and enhance the overall rigidity.

[0056] Reference Figure 2 As shown, the number of the strip reinforcement parts 40 is 3 to 8. In this embodiment, the number of the strip reinforcement parts 40 is 6. The 6 ring-shaped array strip reinforcement parts 40 can not only improve the rigidity of the disc wheel, but also reduce the weight of the disc wheel to the greatest extent. While ensuring uniform force on the wheel rim, redundant design is avoided, the balance between weight and strength is optimized, material cost is reduced, and riding efficiency is improved.

[0057] In this embodiment, the side cover 20 is a double-layer structure, and the inside of the side cover 20 is filled with PMI material. The thickness of the side cover 20 is 1.6-2.0 mm. The side cover 20 is composed of 4-6 layers of carbon fiber material. The thickness of the carbon fiber material is 0.2 mm, and the thickness of the PMI material is 0.8 mm. In this embodiment, 4 layers of carbon fiber material are used, and the overall thickness is 16 mm. Compared with the traditional disc wheel structure, it not only reduces the weight, but also improves the impact resistance and fatigue resistance through the energy absorption characteristics of PMI, thereby extending the service life.

[0058] In this embodiment, the wheel rim 10 is formed by the fusion of 3 to 5 layers of carbon fiber structure. In this embodiment, the wheel rim 10 is formed by the fusion of 5 layers of carbon fiber structure. The flexural stiffness and torsional strength are significantly improved through interlayer synergy, while the carbon fiber ply direction is optimized to cope with complex stresses, taking into account both lightweight and high load-bearing capacity.

[0059] Reference Figures 3 to 11 As shown, a method for manufacturing a lightweight disc wheel reinforcement structure comprises the following steps:

[0060] S1: placing the bottom side cover preform 50, the hub mounting part preform 51 and the rim preform 52 on the lower mold 60;

[0061] S2: Fold the bottom extension portion 42 of the preset strip reinforcement portion 40 to both sides and place it on the bottom side cover preform 50;

[0062] S3: The wheel rim shaping mold 62 is arranged on the outer periphery of the wheel rim preform 52, and the special-shaped three-dimensional airbag group 61 is placed on the side cover preform 50, so that the special-shaped three-dimensional airbag group 61 limits the strip reinforcement portion 40;

[0063] S4: Fold the extension portion 42 at the other end of the strip reinforcement portion 40 to both sides and place it close to the special-shaped three-dimensional airbag assembly 61;

[0064] S5: placing the upper side cover preform 50 on the anisotropic three-dimensional airbag 611, buckling the upper mold 63 and the lower mold 60 to form a disc wheel preform mold, and inflating the anisotropic three-dimensional airbag group;

[0065] S6: Place the disc wheel preform mold in the mold heating box 64, heat and shape it, cool it to form it, and remove the special-shaped three-dimensional air bag group 61 to form a bicycle disc wheel product. Compared with the disc wheel made by gluing, the product formed by one-piece mold can achieve higher standards in terms of precision control. Usually, the precision control of disc wheels made by gluing can only be within 0.5mm, and the reinforced structure of the one-piece molding method can be controlled within 0.2mm. The product quality control can be more refined and the manufacturing cost can be more effectively controlled.

[0066] Reference Figures 4-5 As shown, the wheel rim preform 52 includes a layer of inner disc wheel preform 521, a layer of outer disc wheel preform 522, and several layers of middle disc wheel preforms 523 arranged between the inner disc wheel preform 521 and the outer disc wheel preform 522, and the lower ends of the inner disc wheel preform 521 and the outer disc wheel preform 522 clamp and fix the bottom side cover preform 50.

[0067] Reference Figures 4-5 As shown, the upper end of the inner disc wheel preform 521 is folded inward in a horizontal direction, the upper end of the outer disc wheel preform 522 is arranged in a vertical direction, the upper side cover preform 50 is placed on the special-shaped three-dimensional airbag group 61 and is close to the upper end of the inner disc wheel preform 521, and the outer disc wheel preform 522 is folded downward and is close to the upper side cover preform 50.

[0068] Reference Figure 7As shown, the special-shaped three-dimensional air bag group 61 includes a plurality of air bags 611 corresponding to the strip-shaped reinforcement portion 40, and a plurality of avoidance openings corresponding to the strip-shaped reinforcement portion 40 are arranged in a ring array between adjacent air bags 611 with the hub mounting portion preform 51 as the axis, and the avoidance openings avoid and give way to the strip-shaped reinforcement portion 40.

[0069] The curing temperature of the mold heating and shaping is 160-200°C, the curing time is 30-40min, and the heating rate is 7-10°C / min.

[0070] Reference Figures 12-14 As shown, in order to verify the effect of the above wheel rim, the present design is subjected to finite element analysis by SolidWorks simulation, and for the structure of the present design, the structure without adding the strip reinforcement part is cited as a comparative example for analysis. First, the materials of the embodiment and the comparative example are defined, and the selected material is carbon fiber. The specific performance parameters of the carbon fiber are shown in the following table;

[0071] Table 1 Carbon fiber material properties

[0072] property Numeric unit Elastic modulus 2.3e+11 N / m^2 Poisson's ratio 0.28 not applicable Medium shear modulus 8.38e+10 N / m^2 Mass density 1780 Kg / m^3 Tensile strength 7e+09 N / m^2 Compression strength 8e+08 N / m^2 Yield Strength 5.515e+08 N / m^2

[0073] After the material definition is completed, since this design is a combination of shell elements and solid elements, it is also necessary to define the wheel rim as a shell element with a wall thickness of 0.2mm. The next step is to set the geometric body fixing fixture of the inner ring of the hub mounting part 30. In this embodiment, mainly to verify the structural strength of the disc wheel, a force of 300N is applied to the side cover. The next step is to divide the mesh. The overall mesh unit size is 10mm and the ratio is 1.5. After setting the parameters and generating the mesh, you can start running the example. Fig.12 The analysis results show that the maximum stress of the comparative example is 2.151e+07N / m^2, and the maximum stress of the embodiment is 1.285e+07N / m^2, both of which are much lower than the yield strength of the carbon fiber material 5.515e+08N / m^2. Therefore, it is proved that there is no problem in stress analysis whether the disc wheel structure has the strip reinforcement part 40 or not. Fig.13 The analysis results show that the maximum strain of the comparative example is 2.870e+05N / m^2, and the maximum strain of the embodiment is 2.100e+07N / m^2, which proves that both the wheel rim of the present design and the ordinary wheel rim of the comparative example meet the use requirements of carbon fiber materials; Fig.14The analysis results show that: by comparing the displacement data of the embodiment and the comparative example, it can be seen that the maximum displacement of the embodiment is 1.318e-02mm, and the maximum displacement of the comparative example is 7.047e-02mm. According to the displacement image, the distribution area of ​​the maximum displacement in the comparative example is larger. Therefore, this analysis can effectively prove that under the same force, the present design can reduce the possibility of wheel rim deformation.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A lightweight disc wheel reinforcement structure, characterized in that: include: A wheel rim (10), and side covers (20) arranged at both ends of the wheel rim (10), a hub mounting portion (30) being arranged in the middle of the side covers (20) at both ends, and a plurality of strip reinforcement portions (40) arranged in a circular array along the hub mounting portion (30) being arranged between the side covers (20) at both ends, the strip reinforcement portion (40) comprising a reinforcement portion body (41), and extension portions (42) arranged at both ends of the reinforcement portion body (41) for connecting the side covers (20), the extension portion (42) and the side covers (20) being formed by hot pressing, and the thickness of the strip reinforcement portion (40) being 0.2 to 0.4 mm.

2. A lightweight disc wheel reinforcement structure according to claim 1, characterized in that: The reinforcing portion body (41) is a two-layer thin sheet structure that fits together, and the extending portion (42) is folded toward both sides from the end of the thin sheet structure and fits on the inner wall of the side cover (20).

3. A lightweight disc wheel reinforcement structure according to claim 1, characterized in that: The number of the strip-shaped reinforcement parts (40) is 3 to 8.

4. The lightweight disc wheel reinforcement structure according to claim 1, characterized in that: The side cover (20) is a double-layer structure, the interior of the side cover (20) is filled with PMI material, and the thickness of the side cover (20) is 1.6-2.0 mm.

5. A lightweight disc wheel reinforcement structure according to claim 4, characterized in that: The wheel rim (10) is formed by fusing 3 to 5 layers of carbon fiber structures.

6. A method for manufacturing a lightweight disc wheel reinforcement structure according to any one of claims 1 to 5, characterized in that: The steps include: S1: placing the bottom side cover preform (50), the hub mounting portion preform (51) and the wheel rim preform (52) on the lower mold (60); S2: folding the bottom end extension portion (42) of the preset strip reinforcement portion (40) to both sides and placing it on the bottom side cover preform (50); S3: setting the wheel rim shaping mold (62) on the outer periphery of the wheel rim preform (52), placing the special-shaped three-dimensional air bag group (61) on the side cover preform (50), and the special-shaped three-dimensional air bag group (61) limits the strip-shaped reinforcement part (40); S4: Fold the extension portion (42) at the other end of the strip reinforcement portion (40) to both sides and place it close to the special-shaped three-dimensional air bag assembly (61); S5: placing the upper side cover preform (50) on the anisotropic three-dimensional airbag (611), buckling the upper mold (63) and the lower mold (60) to form a disc wheel preform mold, and inflating the anisotropic three-dimensional airbag assembly (61); S6: placing the disc wheel preform mold in a mold heating box (64), heating and shaping, cooling and forming, and removing the special-shaped three-dimensional air bag group (61) to form a bicycle disc wheel product.

7. The method for manufacturing a lightweight disc wheel reinforcement structure according to claim 6, characterized in that: The wheel rim preform (52) comprises a layer of inner disc wheel preform (521), a layer of outer disc wheel preform (522), and a plurality of layers of middle disc wheel preforms (523) arranged between the inner disc wheel preform (521) and the outer disc wheel preform (522), and the bottom ends of the inner disc wheel preform (521) and the outer disc wheel preform (522) are clamped and fixed to the bottom side cover preform (50).

8. The method for manufacturing a lightweight disc wheel reinforcement structure according to claim 7, characterized in that: The upper end of the inner disc wheel preform (521) is folded inwardly in a horizontal direction, and the upper end of the outer disc wheel preform (522) is arranged in a vertical direction. The upper side cover preform (50) is placed on the special-shaped three-dimensional air bag group (61) and is close to the upper end of the inner disc wheel preform (521), and the outer disc wheel preform (522) is folded downward and is close to the upper side cover preform (50).

9. The method for manufacturing a lightweight disc wheel reinforcement structure according to claim 6, characterized in that: The special-shaped three-dimensional air bag group (61) includes a plurality of air bags (611) corresponding to the strip-shaped reinforcement part (40), and a plurality of avoidance openings corresponding to the strip-shaped reinforcement part (40) are arranged in a ring array between adjacent air bags (611) with the hub mounting part preform (51) as the axis, and the avoidance openings avoid and give way to the strip-shaped reinforcement part (40).

10. The method for manufacturing a lightweight disc wheel reinforcement structure according to claim 6, characterized in that: The curing temperature of the mold heating and shaping is 160-200°C, the curing time is 30-40min, and the heating rate is 7-10°C / min.

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