Bicycle rim and manufacturing process thereof

Abstract

The invention belongs to the technical field of hub machining, and particularly relates to a bicycle rim and a manufacturing process thereof.The bicycle rim comprises a rim body, the section of the rim body is of a hollow structure with the wide upper portion and the narrow lower portion, a first cavity is formed in the rim body, and a plurality of buffering strips protruding inwards are formed on the two sides of the interior of the rim body; symmetrical anti-biting wheel edges are formed on the two sides of the top of the rim body, and the top edges of the anti-biting wheel edges are of cambered surface structures. According to the manufacturing technology, the extruded profile is directly bent, the profile has high plasticity due to the high temperature, the bent profile is cut, cooled, etched and then subjected to heat treatment, the rim is low in strength and easy to machine before heat treatment, the high rim can be machined through the mode, and the manufacturing technology is simple and convenient. Therefore, the running stability and the wind breaking capacity of the bicycle are improved, and meanwhile the high-frame rim has higher strength and impact resistance and is not prone to deformation.

Description

Technical Field

[0001] The present invention belongs to the technical field of hub processing, and particularly relates to a bicycle rim and its manufacturing process. Background Art

[0002] A bicycle hub, that is, a rim, is an important part of a bicycle wheel, undertaking functions such as supporting the wheel, connecting with the axle, and providing rotation. The design and materials of the hub not only affect the performance and riding experience of the bicycle, but also relate to the weight and durability of the whole vehicle; there are many types of hubs, usually including front hubs; rear hubs; integrated hubs; adjustable hubs. According to the materials selected, common hubs can be divided into; aluminum alloy; carbon fiber; steel; high-quality hubs play a key role in the riding experience. It not only affects the comfort and controllability of riding, but also affects the transmission efficiency and response speed of the whole vehicle. Selecting a suitable hub and its configuration can significantly improve the performance of the vehicle.

[0003] However, due to process limitations, it is difficult to manufacture rims with a relatively high rim width for existing bicycle rims. The height of the rim affects the wind-breaking ability, stability, and shock resistance of the vehicle. For relatively high profiles during bending processing, defects such as wrinkling and cross-section are likely to occur, and the defective rate is relatively high.

[0004] To solve the above problems, it is urgent to propose a high-rim bicycle rim and its manufacturing process. Summary of the Invention

[0005] To solve the problems raised in the above background art. The present invention provides a bicycle rim and its manufacturing process, which have characteristics such as high stability, high wind-breaking ability, and high seismic resistance, can obtain high-quality high-rim rims, and change the problem that it is difficult to manufacture high-rim rims with the existing process.

[0006] To achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides a bicycle rim. The rim includes an integrally formed rim body. The cross-section of the rim body is a hollow structure that is wider at the top and narrower at the bottom. A first cavity is formed inside the rim body. A number of buffer bands protruding inward are formed on the inner circumferences of both sides inside the rim body. Symmetrical anti-bite wheel rims are formed on both sides of the top of the rim body. The top edge of the anti-bite wheel rim is an arc surface structure or a groove structure; a second cavity is formed inside the anti-bite wheel rim, and the second cavity and the anti-bite wheel rim form a hollow convex rim. A tire slot is formed on the surface of the rim body at the middle position between the two anti-bite wheel rims; Among them, the buffer bands inside the rim body are a number of uniformly distributed corrugated groove structures.

[0007] Preferably, the corrugation period of the corrugated groove structure is 5-8 mm, the wave amplitude is 1.2-1.8 mm, and the corrugation inclination angle is 45±5°.

[0008] Preferably, the top edge of the anti-bite wheel edge 13 is a continuous arc with a radius of 2.5 mm - 3 mm.

[0009] Preferably, a plurality of mounting holes are provided on the inner side of the rim body.

[0010] Preferably, the outer surface of the rim body has an electroplated layer.

[0011] Preferably, the height of the rim body is 45 mm to 65 mm.

[0012] In a second aspect, the present invention further provides a manufacturing process for a bicycle rim, which is applied to the aforementioned bicycle rim and includes the following steps: S1, using an eddy current heating device to heat and soften an aluminum-magnesium alloy rod, and then using a hydraulic profile extruder. The pressure of the hydraulic profile extruder cooperates with a mold to extrude the rod into a profile. The cross-sectional shape of the mold cavity matches the final cross-sectional shape of the rim body, including a hollow structure that is wider at the top and narrower at the bottom, preformed grooves for buffer bands that protrude inward on both sides, and a forming cavity for the anti-bite wheel edge at the top; S2, after the profile is extruded, direct bending processing is carried out. Specifically: when the profile is in a high-temperature state of 380 - 450 °C, use the profiling roller group of a metal bending machine for bending processing. The profile of the roller group matches the cross-sectional shape of the rim body. When bending, the wider part at the top faces outward, and through the control of the roller pressure, directional deformation is generated on the buffer band side; the extruded profile is bent into a spiral shape of 3 to 5 turns, and the remaining profile is cut off; S3, put the spiral profile into a cutting machine and perform cutting processing along the cross-sectional direction to form a number of annular rims with notches; S4, dissipate heat from the rim and cool it to room temperature; S5, pickle the cooled rim to clean impurities and contaminants on the surface, and at the same time etch the surface; S6, perform heat treatment on the rim processed in step S5, including solution treatment and aging treatment; S7, weld the notches of the heat-treated rim; S8, after welding is completed, perform milling processing to remove the weld scars generated by welding; S9, after removing the weld scars, perform electroplating processing to form a coating on the surface of the rim; S10, uniformly drill holes in the rim to open holes for installing spoke assemblies and tire valves.

[0013] Preferably, after cutting the remaining profiles in step S2, it further includes: clamping out the bent profiles by a manipulator, and the metal bending machine continues to perform the bending process on the next section of profiles.

[0014] Preferably, the cutting process in step S3 is specifically: putting the spiral profiles into a cutting machine by a manipulator, and cutting all the turns of the profiles in one cut along the cross-sectional direction to form several annular rims with notches.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The manufacturing process of the present invention directly performs bending processing on the extruded profiles, utilizes the relatively high temperature reached by the profiles during the extrusion process, endows them with good plasticity, and makes the bending process simpler and more efficient. Specifically, performing the bending operation at a high temperature can effectively reduce the processing difficulty of the material, improve the bending quality at the same time, and ensure the shape accuracy and consistency of the rims.

[0016] The profiles after bending will go through subsequent processes such as cutting, cooling, and etching. This series of treatments not only ensure that the profiles reach the designed size and appearance requirements, but also lay a foundation for the subsequent heat treatment. During the heat treatment process, although the strength of the rims is relatively low at this stage, it also makes the material easier to further process. After the heat treatment, the strength of the material will be significantly improved, thus greatly enhancing the overall performance of the rims.

[0017] The high-profile rims manufactured by this process have a higher height and strength. The high-profile rims not only improve the driving stability and wind-breaking ability of the bicycle, but also, due to their superior geometric shape and structural design, can effectively disperse impacts and pressures, thereby enhancing the impact resistance and rigidity of the entire rim. This characteristic makes the rims less likely to deform when facing uneven roads, potholes, etc., thus providing a safer and more reliable use experience for cyclists.

[0018] In addition, the design of the high-profile rims also helps to improve the aerodynamic performance of cycling and reduce wind resistance. The reduction of wind resistance can enable cyclists to feel less resistance during long rides, enhancing the efficiency and speed performance of cycling. This rim design significantly promotes the development of bicycle technology, enabling it to fully exhibit excellent performance in both competitive and daily cycling.

[0019] In summary, the manufacturing process of the present invention not only improves the strength and performance of the rims by optimizing the bending processing and heat treatment of the profiles, but also significantly reduces the processing difficulty. This innovative process realizes the improvement of the high-profile rims in terms of stability, impact resistance, and aerodynamic performance, brings a better cycling experience to consumers, and promotes the technological progress and development of the bicycle industry. Brief Description of the Drawings

[0020] The accompanying drawings are used to provide a further understanding of the present invention and form a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the accompanying drawings: Figure 1 is a schematic structural view of the rim body of the first embodiment of the present invention; Figure 2 is a three-dimensional schematic view of the cross-section of the rim body of the first embodiment of the present invention; Figure 3 is a schematic cross-sectional structural view of the rim body of the first embodiment of the present invention; Figure 4 is a schematic cross-sectional structural view of the rim body of the second embodiment of the present invention; In the figure: 1, rim body; 11, first cavity; 12, second cavity; 13, anti-bite wheel rim; 14, tire card slot; 15, buffer belt. Detailed implementation manners

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] Embodiment 1 As Figures 1 to 3 shown; A bicycle rim includes an integrally formed rim body 1. The cross-section of the rim body 1 is a hollow structure that is wider at the top and narrower at the bottom. A first cavity 11 is formed inside the rim body 1. A number of inwardly protruding buffer belts 15 are formed on the inner circumferences of both sides inside the rim body 1. Symmetrical anti-bite wheel rims 13 are formed on both sides of the top of the rim body 1. The top edge of the anti-bite wheel rim 13 is an arc-shaped structure. A second cavity 12 is formed inside the anti-bite wheel rim 13. The second cavity 12 and the anti-bite wheel rim 13 form a hollow convex rim. A tire card slot 14 is formed on the surface of the rim body 1 at the middle position between the two anti-bite wheel rims 13.

[0023] In this implementation manner: The hub of a bicycle, that is, the rim, plays a crucial role throughout the ride. It not only affects the riding stability and wind-breaking ability but also is directly related to the impact resistance and the service life of the tire. In order to improve the overall performance of the bicycle, the present invention designs a new type of rim body 1 with a relatively high rim design, aiming to improve the mechanical properties and structural stability of the hub.

[0024] In this design, the rim body 1 adopts the structural design of the first cavity 11. This innovative design has successfully reduced the overall weight of the rim. The reduced weight helps to improve the overall performance of the bicycle, reduce the energy consumption during riding, and thus improve the riding efficiency and comfort.

[0025] In the embodiment of the present invention, as Figures 2 - 3 shown, several inwardly protruding buffer bands 15 are of a corrugated groove structure evenly distributed, symmetrically distributed on both sides inside the rim body 1, with a depth of about 2.5 - 3 mm from the inner wall surface. The buffer bands 15 are integrally formed with the rim body 1.

[0026] In the preferred embodiment of the present invention, for the corrugated groove structure of the buffer band 15, the corrugation period is 5 - 8 mm, the wave amplitude is 1.2 - 1.8 mm, and the corrugation inclination angle is 45 ± 5°.

[0027] Through the buffer band 15 with a corrugated groove structure, the present invention can play a role in stress buffering during the bending process of the rim profile. Specifically, during profile extrusion, the corrugated pre - forming groove in the die guides the metal flow to form an initial stress release channel; during high - temperature bending, the corrugated structure of the buffer band 15 allows the stress to be preferentially concentrated at the grooves of the buffer band 15, avoiding transmission to key structures of the rim, such as the anti - bite wheel edge 13 or the welding notch, etc. Specifically, during bending, the outer - ring metal of the rim body 1 is stretched, and the corrugated structure can absorb the elongation through corrugation expansion; during bending, the inner - ring metal of the rim body 1 is compressed, and the corrugated structure can provide a contraction space through corrugation shrinkage. Thus, the stress during high - temperature bending can be relieved. Through finite - element analysis and physical experiment tests, the present invention finds that compared with the traditional rim structure without the buffer band 15, under the impact condition of 25 km / h, the buffer band 15 with a corrugated groove structure can reduce the stress concentration coefficient from 3.8 to 2.1, and can reduce the peak value of the bending stress by up to 42%. This undoubtedly breaks through the technical difficulty that the stress cannot be effectively relieved during the traditional rim processing.

[0028] Through the buffer strip 15 with a corrugated groove structure, the present invention can also improve the bearing capacity during the use of the wheel rim. Specifically, first, the corrugated structure can convert the radial load force F into multi-directional component forces, which can be specifically expressed as: F = F_{vertical}·sinθ + F_{horizontal}·cosθ, where θ is the corrugation inclination angle, F_{vertical} is the component force of the radial load force F in the vertical direction, and F_{horizontal} is the component force of the radial load force F in the horizontal direction. Dynamic tests show that the wheel rim with the buffer strip 15 of the present invention has a more uniform load distribution, increasing the radial stiffness of the wheel rim by 22% while reducing the weight by 9%. Secondly, the corrugated units of the corrugated structure have a progressive response from elastic deformation to plastic deformation when loaded. It is proved by the drop hammer experiment that the wheel rim with the buffer strip 15 of the present invention can absorb 15 - 18% more impact energy.

[0029] It can be seen that the buffer strip 15 can effectively reduce the stress of the metal material generated due to bending processing, enabling the inner ring metal to have movable space during shrinkage and ensuring that the outer ring metal can adapt to the requirements of tensile deformation. In this way, the reject rate during the production of high-profile wheel hubs is effectively reduced, the yield rate of the product during the processing is improved, and the production efficiency is significantly increased.

[0030] In addition, compared with the traditional flat structure, the corrugated structure of the buffer strip 15 can more effectively absorb and disperse the instantaneous impact and vibration generated during the bending process. This buffering effect will significantly reduce the risk of damage caused by plastic deformation of the metal during the processing, thereby improving the overall production yield of the high-profile wheel rim. At the same time, the corrugated design of the material also enhances the toughness of the wheel rim, enabling it to better resist external impacts during use.

[0031] During actual riding, the performance of the wheel rim is particularly affected by the severe impacts during turning and bumpy roads. When turning / bumpy, due to the concentration of weight / pressure, the tire and the wheel hub are squeezed at the edge of the wheel hub. In these cases, a large shear force will be generated at the edge position of the tire and the wheel hub, and this shear force is likely to cause rim cutting damage to the tire (commonly known as snake bite rupture in the industry). To solve the problem of rim cutting damage of the existing wheel rim, the wheel rim body 1 of the present invention is designed with anti-bite rims 13 on both sides of the top. This design is in direct contact with the bicycle tire and adopts an arc surface design, which can effectively disperse the shear force concentrated here. This dispersion mechanism significantly reduces the occurrence probability of the snake bite phenomenon and enhances the safety and stability of riding.

[0032] Specifically, the top edge of the anti-bite rim 13 is a continuous arc with a radius of 2.5 mm - 3 mm; the second cavity 12 forms a flexible deformation zone, where the wall thickness of the second cavity 12 in the anti-bite rim 13 is 1.2 - 1.5 mm; at the same time, to improve the durability of the anti-bite rim 13, electroplating treatment is carried out on the contact surface, and the thickness of the electroplating layer is about 1 μm.

[0033] In this embodiment: The continuous arc design of the top edge of the anti-bite rim 13 can effectively disperse stress, significantly reduce the risk of rim cutting damage, and enhance the safety and stability of cycling. The combination of the second cavity 12 and the anti-bite rim 13 forms a hollow convex rim. This innovative structure not only effectively reduces the overall weight of the rim body 1, but also the hollow structure absorbs energy through plastic deformation, playing a significant role in enhancing performance.

[0034] The design of the hollow convex rim enables the rim body 1 to be lighter while maintaining strength and rigidity, reducing the amount of material used. This lightweight design has a positive impact on the overall performance improvement of the bicycle. Especially when cycling, it reduces inertia, improves acceleration performance, and enhances the rider's control experience. At the same time, reducing the weight of the rim helps the rider reduce fatigue during long-term use, making cycling more relaxed and enjoyable.

[0035] In addition, the existence of the second cavity 12 is not only for weight reduction, but more importantly, it further improves the buffering performance of the anti-bite rim 13. This cavity utilizes the elastic properties of air and can effectively absorb part of the impact force when the rim is subjected to external impact or pressure. This buffering effect reduces the violent shear force generated when the tire contacts the ground, significantly reducing the risk of snake bite (the phenomenon of the tire sidewall being pinched and ruptured).

[0036] The anti-bite rim 13 is designed with an arc structure. Its combination with the second cavity 12 creates an effect that goes beyond traditional anti-bite designs. At the same time, the above design of the anti-bite rim 13 also cooperates with the corrugated buffer strip 15. The corrugated structure of the buffer strip 15 provides radial elasticity (radial refers to the direction perpendicular to the axis of rotation of the rim (i.e., the direction of the wheel radius). Radial elasticity means that when the rim body is stretched (outer ring), the corrugations expand to absorb the elongation deformation and reduce stress concentration. When the rim body is compressed (inner ring), the corrugations shrink to provide contraction space and prevent wrinkling). The cavity structure of the anti-bite rim 13 provides axial flexibility (axial refers to the direction parallel to the axis of rotation of the rim (i.e., the direction of the wheel width). Axial flexibility means that when the cavity structure of the anti-bite rim 13 is subjected to a lateral impact, the second cavity 12 absorbs energy through plastic deformation, and the arc surface / groove design disperses the contact stress), achieving system stiffness matching. When subjected to a severe impact, the buffer strip 15 first absorbs high-frequency vibrations, and then the anti-bite rim 13 dissipates low-frequency energy, thereby optimizing the dynamic response.

[0037] The anti-bite wheel rim 13 of the present invention is designed with an innovative design of arc surface contact + hollow energy absorption. When the tire runs on the road surface, the dynamic load and shear force caused by the uneven road surface will be evenly distributed to the rim body 1 through the anti-bite wheel rim 13. This design not only enhances the cooperation between the tire and the rim, but also utilizes the elastic absorption characteristics of the second cavity 12 to further improve the overall stability and safety.

[0038] In addition, a tire slot 14 is provided in the rim body 1. This slot can not only accurately position the tire, but also accommodate the end of the support spoke of the bicycle. This design effectively prevents the contact between the tire and the end of the support spoke, further protecting the tire and extending its service life. Through this protection measure, the vehicle owner does not need to worry about accidental damage during the ride, thus improving the overall safety and reliability of the ride.

[0039] In an alternative embodiment, a plurality of mounting holes are provided on the inner side of the rim body 1.

[0040] In this embodiment: A plurality of mounting holes are provided on the inner side of the rim body 1, and this design plays an important role in the structural stability and functionality of the rim. These mounting holes are not only used to mount key components such as wheel spokes and valve cores, but also ensure the tight connection between the rim body 1 and other components, thereby improving the safety and reliability of the whole vehicle.

[0041] Specifically, the arrangement of the mounting holes allows the wheel spokes to be evenly distributed on the rim body 1. This design can effectively transmit the force of the wheel evenly to the rim, enhancing the strength of the overall structure. When riding, when the wheel bears the impact force from the ground or the centrifugal force during driving, the spokes are tightly connected to the rim body 1 through the mounting holes, ensuring the effective transmission of force and reducing the occurrence of local stress concentration, thereby improving the durability and service life of the wheel.

[0042] The design of the mounting holes also makes the combination between the rim body 1 and other components more flexible, facilitating the future adaptation of different types of wheel accessories, and can be quickly replaced and adjusted according to the needs of the rider. Whether it is a lightweight wheel for competition or a durable mountain riding accessory, the diverse mounting hole design can meet the needs of riders with different styles and requirements.

[0043] Furthermore: In an alternative embodiment, the outer surface of the rim body 1 has a plating layer.

[0044] In this embodiment, the outer surface of the rim body 1 has an electroplating layer, which not only significantly improves the functionality of the rim, but also makes an important contribution to the aesthetics. The application of the electroplating layer provides the rim body 1 with higher surface hardness and excellent corrosion resistance, thereby extending its service life and improving safety.

[0045] The electroplating layer improves hardness, making the rims better able to resist wear when subjected to various external impacts and friction. This enhanced hardness helps keep the rims intact over long periods of riding and on different terrain conditions, reducing the occurrence of surface scratches and damage.

[0046] In terms of corrosion resistance, the electroplating layer provides an effective protective barrier for the rims, blocking the erosion of potential corrosive substances such as moisture, salt, acid and alkali substances. It can effectively prevent rust and oxidation, and keep the appearance and performance of the rims as good as new. This corrosion resistance ensures the stability and safety of the rims in various climatic conditions and improves the durability of the entire bicycle.

[0047] In addition, electroplating can significantly improve the appearance of the rim. The smooth and bright electroplated surface can attract the attention of riders and consumers, adding a layer of fashion and modernity to the rim body 1. This beautiful surface treatment not only enhances the overall value of the product, but also meets consumers' pursuit of personalization and visual appeal, adding more trendy elements to cycling.

[0048] Going further: In an optional embodiment, the height of the rim body 1 is 45 mm to 65 mm.

[0049] In this embodiment: the height of the rim body 1 of the present invention can reach 45mm to 65mm, which exceeds the common rim height on the market (generally 20-35mm). The higher rim body 1 performs well in terms of wind-breaking performance. Its increased height enables the rim to delay airflow separation and reduce tail vortices during driving, which can more effectively cut the air and reduce the resistance of the airflow. This design is particularly suitable for high-speed riding, and can significantly reduce air resistance and improve the rider's speed performance. The increased rim height also directly improves the stability of the vehicle when driving at high speeds. In the case of high-speed riding, the impact of airflow on the wheel may lead to unstable dynamic effects, and a rim design with a greater height helps to enhance the stability of the wheel, thereby reducing the feeling of bumps and shaking.

[0050] At the same time, the high frame design of the rim body 1 also achieves a structural strengthening effect by increasing the cross-sectional height of the rim. Specifically, after testing, when the high frame design of the rim body 1 of the present invention is within the height range of 45-65 mm, the measured bending stiffness is increased to 3.3 times that of the traditional low-frame rim, significantly improving the anti-deformation ability.

[0051] Furthermore, the high frame design of the rim body 1 also achieves the effect of suppressing vibration by increasing the cross-sectional height of the rim. Specifically, the natural frequency (≈85 Hz) of the high frame structure is far away from the road excitation frequency band (5-30 Hz), thereby effectively suppressing vibration.

[0052] Embodiment 2 like Figure 4 As shown, the present invention also provides a bicycle rim, which is different from the first embodiment only in the anti-bite wheel edge 13, and the rest of the structure is the same as the first embodiment, which will not be repeated here. In order to further enhance the performance of the anti-bite wheel edge 13, this embodiment adds a groove structure on the top edge of the anti-bite wheel edge 13.

[0053] The primary function of the groove design is to disperse the shear force concentrated on the anti-bite wheel edge 13. During bicycle riding, the tire and the edge of the rim will be subject to greater pressure, especially when turning, bumping or going downhill quickly, the contact point between the rim and the tire is often subjected to huge impact force. The traditional anti-bite wheel edge 13 cannot effectively disperse these forces and is prone to cracks or damage at the contact point. The design with the addition of grooves can create multiple stress points on the rim surface, slowing down and dispersing the concentrated effect of external forces, thereby significantly improving the rim's ability to resist pressure when encountering impacts and reducing the risk of rim deformation and damage.

[0054] Secondly, the groove structure reduces the friction between the tire and the rim. The groove structure of the anti-bite wheel edge 13 can effectively reduce the friction between the tire and the rim, especially when riding at high speed, excessive friction can easily cause tire wear and even scratches. The groove provides a tiny air gap and buffer zone, so that during the rotation process, the contact force between the rim and the tire is properly distributed, effectively reducing the friction coefficient, thereby extending the service life of the tire and the rim.

[0055] In addition, the groove design is not only to increase the compression resistance of the rim, but also to improve the stability and rigidity of the top structure of the rim by optimizing the force distribution. Due to the presence of the groove, the anti-bite wheel edge 13 can distribute the stress more evenly when subjected to external force, reducing the possibility of local plastic deformation or fracture of the rim due to excessive local stress. Especially at the connection between the tire and the rim, the addition of the groove improves the bearing capacity of the entire structure.

[0056] Although the addition of grooves adds a certain degree of complexity to the manufacturing process of the rim, due to its subtle depth and width, the grooves as a whole do not have too much impact on the weight of the rim. On the contrary, it achieves a lightweight design of the rim by optimizing the use of materials while ensuring sufficient strength and performance. The reduced weight helps improve the acceleration performance and handling flexibility of the bicycle and reduce energy consumption during riding.

[0057] Embodiment 3 The present invention also includes a manufacturing process for a bicycle rim, which is used to form the bicycle rims described in the first and second embodiments. In order to clearly illustrate the specific manufacturing process of the present invention, the following process will be carried out by taking the preparation of the bicycle rim of the first embodiment as an example, and specifically includes the following steps: S1, using eddy current heating equipment to heat and soften the aluminum-magnesium alloy bar, and then using a hydraulic profile extruder and a pressure-matching die of the hydraulic profile extruder to extrude the bar into a profile; specifically, First, material selection is performed: the wheel rim of the present invention adopts high-strength aluminum-magnesium alloy material with excellent strength and light weight characteristics. Material selection directly affects the comprehensive performance of the wheel rim. Aluminum-magnesium alloy has high strength and corrosion resistance, while further reducing the weight of the wheel rim.

[0058] In the preferred embodiment of the present invention, before formally entering into production, the material is also pickled to remove oxides, impurities and oil stains on the surface in preparation for subsequent processing.

[0059] Secondly, profile extrusion is performed: the aluminum-magnesium alloy bar is heated to a softened state by an eddy current heating device, and the temperature is controlled between 400-500° C. Then, the softened bar is extruded into shape by a hydraulic profile extruder in combination with the special mold of the present invention. During the extrusion process, it is ensured that the geometric shape and size of the mold meet the rim design requirements to form a high-strength rim profile.

[0060] Furthermore, the special mold includes an upper mold and a lower mold, and the upper mold and the lower mold cooperate to form a mold cavity structure. The cross-sectional shape of the mold cavity structure of the special mold in step S1 matches the final cross-sectional shape of the rim body 1, including a hollow structure that is wide at the top and narrow at the bottom, buffer belt pre-formed grooves protruding inward on both sides, and a top anti-bite wheel edge forming cavity.

[0061] The buffer belt preforming groove of the mold is designed as a corrugated strip groove with a depth of 1 / 3-1 / 2 of the profile thickness and a spacing of 3-5 mm; The cross section of the profile after extrusion molding with a special die includes: a main structure that is wide at the top and narrow at the bottom (for example, a width ratio of 1.2:1), pre-formed buffer belt protrusions on both sides (for example, a height of 2-3mm), and a thickened edge on the top to form an anti-bite wheel edge; S2, bending process is directly performed after profile extrusion; In an alternative embodiment, the bending process in S2 is specifically as follows: while the profile is maintained at a high temperature of 380 - 450 °C (the high temperature state of 380 - 450 °C can ensure that the material has sufficient plasticity to avoid cracks or damage. This process enhances the structural stability of the rim and optimizes the geometry), the profiling roller set of the metal bending machine is used for bending. The profile of the roller set matches the cross-sectional shape of the rim body. When bending, the wider upper part faces outwards, and directional deformation is generated on the buffer strip side by controlling the roller pressure; the extruded profile is bent into a spiral shape of 3 to 5 turns, the remaining profile is cut off, and the bent profile is clamped out by a manipulator, and the metal bending machine continues to perform the bending process on the next section of the profile.

[0062] It should be noted that: in the processing and manufacturing of high-profile wheels, due to the direct bending process after profile extrusion, the high-temperature aluminum-magnesium alloy profile has better plasticity. This improvement in plasticity enables the metal material to be more easily stretched and contracted during the bending process, thereby forming a three-dimensional and complex high-profile wheel shape to meet the design requirements.

[0063] Especially in the internal design of the rim body 1, a buffer strip 15 is added. This design not only enhances the overall structural strength of the wheel hub but also effectively absorbs the impact and vibration generated during use. The presence of the buffer strip 15 allows the rim body to effectively relieve the concentration of internal and external stresses during the bending process. The wheels processed in this way not only have higher toughness and stability in structure but also maintain better performance under dynamic loads.

[0064] In addition, due to the high adaptability and controllability of the profile during the forming process, the manufactured high-profile wheels also achieve a good balance in terms of weight and strength. This design concept enables the wheels to effectively improve the handling and safety of the vehicle in practical applications, especially outstanding in high-speed riding or complex terrains.

[0065] S3, place the spiral profile into a cutting machine and perform cutting along the cross-sectional direction; Cutting process: The bent spiral profile will enter the cutting machine for cutting and is cut off in one cut along the cross-sectional direction to form several annular rims with notches. This cutting operation can ensure that the size and shape of each part of the rim meet the accuracy requirements. Specifically: Place the spiral profile in a cutting machine with a limiting fixture; Perform a one-time cut along the cross-sectional direction perpendicular to the spiral axis; After cutting, several open annular rim blanks with a standard circumference ±5% error are formed.

[0066] S4, dissipate heat and cool down to room temperature; Cooling and heat dissipation: The cut rim is quickly cooled to room temperature. During the cooling process, the rim is kept in a radially constrained state to ensure the stability of the rim shape and avoid deformation caused by temperature differences.

[0067] Furthermore, it is cooled to room temperature at a rate of 10 - 15 °C / min in a temperature-controlled cooling chamber.

[0068] S5. Pickle the rim to clean the impurities and contaminants on the surface and etch the surface simultaneously. Specifically: Pickling and cleaning: After the rim is cooled, it enters the pickling tank. The oxide layer, impurities, and contaminants on the rim surface are cleaned by a mixed acid solution with a pH of 3.5 - 4.0. Pickling not only improves the surface finish of the rim but also effectively removes the stains during the production process. The pickling time is 15 - 20 minutes.

[0069] Surface etching: After pickling, surface etching treatment is carried out to ensure the uniformity of the rim surface and improve the electroplating effect.

[0070] Due to the pressure exerted on the profile surface during bending processing, there are certain scratches and oil stains on the profile surface, and an oxide layer is formed on the profile surface during the cooling process. To facilitate the subsequent repair of the rim surface, the rim is pickled at this time, which can wash away the stains on the surface. Hydrochloric acid, sulfuric acid, phosphoric acid and other pickling reagents are used during the pickling process. The purpose is to remove the stains and the oxide layer on the rim surface to facilitate the subsequent electroplating treatment of the rim surface.

[0071] S6. Heat-treat the rim to improve its strength. Specifically, it includes: Solution treatment and aging treatment: The rim after pickling and etching enters the heat treatment furnace. In the furnace, the rim undergoes solution treatment (such as heating to 520 - 550 °C and holding for a period of time, such as 1 - 1.5 hours) to make the alloy elements evenly distributed. Then aging treatment is carried out (such as heating to 160 °C and holding for 8 hours). This step significantly improves the strength and hardness of the rim and improves its wear resistance and impact resistance.

[0072] When heat treatment is carried out, the rim is in an environment with protective gas under high temperature and high pressure. After heating, holding, and cooling, the metallographic structure of the metal changes, thereby improving the overall quality and strength of the rim.

[0073] S7. Weld the notch of the heat-treated rim; adopt the friction welding process, with a welding pressure of 8 - 10 MPa; a rotational speed of 1200 - 1500 rpm, and a welding time of 30 - 45 seconds; Welding: Welding treatment is carried out at the notch formed by cutting the heat-treated rim in step S3. The friction welding technology is used to connect the rim joints. Friction welding can ensure that the joint strength is consistent with the rim body and avoid defects caused by improper welding.

[0074] When welding, by means of friction welding, both ends of the wheel rim are respectively installed on two clamping platforms of a friction welding machine. After high-speed relative oscillation, the two ends of the wheel rim rub violently, generating high temperature to achieve welding. Using friction welding can ensure that the strength of the welded part of the wheel rim is the same as that of the wheel rim itself, belonging to the same material. This method can avoid uneven mass distribution of the wheel rim and further improve the stability of the wheel rim.

[0075] S8, after welding is completed, milling and cutting processing is carried out to remove the welding scars; mill the welding surplus height, and control the surface roughness below Ra3.2 to ensure the flatness and dimensional accuracy of the wheel rim.

[0076] S9, after removing the welding scars, electroplating processing is carried out to form a coating on the surface of the wheel rim; specifically, electroplating processing: after milling and cutting, electroplating treatment is carried out on the surface of the wheel rim. Through anodic electroplating technology, the coating is evenly covered on the surface of the wheel rim to improve its corrosion resistance, wear resistance and appearance quality. Commonly used electroplated metals include nickel, chromium, etc. The thickness of the electroplated layer needs to be strictly controlled to ensure the service performance and durability of the wheel rim. For example, first plate a 5 - 8μm nickel bottom layer, and then plate a 10 - 15μm hard chromium layer.

[0077] Using anodic electroplating technology, according to requirements, chromium plating, nickel plating, etc. can be carried out on the surface of the wheel rim, which can improve the surface smoothness, corrosion resistance and surface strength of the wheel rim. Since the surface oxide layer is removed by pickling, it is beneficial for the coating to adhere evenly and firmly to the surface of the wheel rim.

[0078] S10, evenly drill holes in the wheel rim to open the hole positions for installing the spoke assembly and the tire valve. Use a CNC drill to process the spoke holes; the angular error of the hole position spacing is ≤0.5°. Specifically: according to the design requirements, precisely drill holes at the installation holes of the wheel rim for the hole positions of installing the spokes and the tire valve. Use CNC equipment to accurately control the hole position and hole diameter (such as the hole diameter is 2.5±0.05mm) to ensure the tight fit between the spokes and the wheel rim and avoid deformation or unstable performance of the wheel rim caused by inaccurate hole positions.

[0079] After step S10, it also includes: Final inspection and quality control: After completing all the above technological processes, strict quality inspection is carried out to ensure that aspects such as the strength, size, appearance, welding quality, and surface treatment effect of the wheel rim meet the standards. Performance testing: Simulate the use environment to test some wheel rims to test the impact resistance, anti-deformation ability, corrosion resistance and service life of the wheel rims, etc., to ensure that each product meets the standards.

[0080] It further includes packaging and ex-factory: The qualified rims after quality inspection are cleaned, dried, and packaged in a suitable way to ensure no damage during transportation. Ex-factory: The packaged rims enter the warehouse and are ready for ex-factory to ensure that the products can be delivered to customers on time.

[0081] The working principle and usage process of the present invention: The rim body 1 of the present invention adopts the structural design of the first cavity 11. This innovative design successfully reduces the overall weight of the rim. The reduced weight helps to improve the overall performance of the bicycle, reduce the energy consumption during cycling, and thus enhance the cycling efficiency and comfort. At the same time, the buffer band 15 provided inside the rim body 1 plays an important role in the bending process of the rim profile. The buffer band 15 can effectively reduce the stress of the metal material generated due to the bending process, enabling the inner ring metal to have movable space during contraction and ensuring that the outer ring metal can adapt to the requirements of tensile deformation. In this way, the reject rate of high-profile wheels during the production process is effectively reduced, the yield rate of the products during the processing is improved, and the production efficiency is significantly increased.

[0082] In addition, a tire slot 14 is provided in the rim body 1. This slot can not only accurately position the tire but also accommodate the end heads of the support spokes of the bicycle. This design effectively prevents the contact between the tire and the end heads of the support spokes, further protecting the tire and extending its service life. Through this protective measure, the vehicle owner does not need to worry about accidental damage during cycling, thus improving the overall cycling safety and reliability; The manufacturing process adopted by the rim body 1 of the present invention directly bends the extruded aluminum-magnesium alloy profile. Utilizing the relatively high temperature reached by the profile during extrusion, it endows the profile with good plasticity, making the bending process simpler and more efficient. Conducting the bending operation at a high temperature can effectively reduce the processing difficulty of the material, improve the bending quality at the same time, and ensure the shape accuracy and consistency of the rim.

[0083] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A bicycle rim, characterized in that: The rim comprises an integrally formed rim body (1), the cross section of the rim body (1) being a hollow structure that is wide at the top and narrow at the bottom, a first cavity (11) being formed inside the rim body (1), a plurality of inwardly protruding buffer zones (15) being formed on the inner circumference of both sides of the rim body (1), symmetrical anti-bite wheel edges (13) being formed on both sides of the top of the rim body (1), the top edge of the anti-bite wheel edge (13) being a curved surface structure or a groove structure; a second cavity (12) is formed inside the anti-bite wheel edge (13), the second cavity (12) and the anti-bite wheel edge (13) forming a hollow convex edge, and a tire groove (14) being formed on the surface of the rim body (1) at a position between the two anti-bite wheel edges (13); Wherein, the buffer zone (15) inside the wheel rim body (1) is a plurality of evenly distributed corrugated groove structures.

2. The bicycle rim according to claim 1, characterized in that: The corrugated groove structure has a corrugation period of 5-8 mm, an amplitude of 1.2-1.8 mm, and a corrugation inclination angle of 45±5°.

3. The bicycle rim according to claim 2, characterized in that: The top edge of the anti-bite wheel edge (13) is a continuous arc with a radius of 2.5mm-3mm.

4. The bicycle rim according to claim 3, characterized in that: A plurality of mounting holes are provided on the inner side of the rim body (1).

5. The bicycle rim according to claim 4, characterized in that: The outer surface of the rim body (1) has an electroplating layer.

6. The bicycle rim according to claim 4, characterized in that: The height of the rim body (1) is 45 mm to 65 mm.

7. A manufacturing process for a bicycle rim, applied to the bicycle rim according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1, using eddy current heating equipment to heat and soften the aluminum-magnesium alloy bar, and then using a hydraulic profile extruder, the pressure-matching mold of the hydraulic profile extruder extrudes the bar into a profile. The cross-sectional shape of the mold cavity matches the final cross-sectional shape of the rim body, including a hollow structure that is wide at the top and narrow at the bottom, buffer belt pre-formed grooves protruding inward on both sides, and a top anti-bite wheel edge forming cavity; S2, after the profile is extruded, the bending process is directly carried out, specifically: the profile is kept at a high temperature of 380-450℃, and the bending process is carried out using the contour roller group of the metal bending machine. The roller group profile matches the cross-sectional shape of the rim body. When bending, the upper wide part faces outward, and the buffer belt side is directional deformed by roller pressure control; the extruded profile is bent into a spiral shape of 3 to 5 turns, and the remaining profile is cut; S3, placing the spiral profile into a cutting machine, and cutting it along the cross-sectional direction to form a plurality of annular rims with notches; S4, dissipating heat from the wheel rim and cooling it to room temperature; S5, pickling the cooled rim to clean the impurities and contaminants on the surface and etching the surface; S6, heat treating the rim after the treatment in step S5, including solution treatment and aging treatment; S7, welding the notch of the rim that has been heat treated; S8, after the welding is completed, milling is performed to remove the weld scars produced by the welding; S9, after removing the welding scar, electroplating is performed to form a coating on the surface of the rim; S10, drill holes evenly on the rim to create holes for installing the spoke assembly and the tire valve.

8. The manufacturing process of the bicycle rim according to claim 7, characterized in that: After the remaining profile is cut off in step S2, the following steps are further performed: the profile after the bending process is clamped out by a robot, and the metal bending machine continues to perform the bending process on the next section of the profile.

9. The manufacturing process of the bicycle rim according to claim 7, characterized in that: The cutting process in step S3 is specifically as follows: the spiral profile is placed into a cutting machine by a robot, and all the circles of the profile are cut off along the cross-sectional direction with one knife to form a plurality of annular rims with gaps.

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