A type of exercise bike with an eccentric self-rotating flywheel structure

Abstract

This utility model relates to the field of fitness equipment technology, and more particularly to a fitness bike with an eccentric self-rotating flywheel structure, comprising: a flywheel shaft rotatably mounted on a frame; two cranks respectively connected to the two ends of the flywheel shaft; and a flywheel; characterized in that it further comprises: an eccentric rotating disc driven by the flywheel shaft to perform circumferential eccentric oscillation, the outer edge of which is provided with alternating continuous arc-shaped grooves and arc-shaped protrusions forming arc-shaped ripples along the circumference; the eccentric rotating disc is connected to the flywheel through a one-way transmission mechanism; an outer ring is fixedly disposed on the outside of the eccentric rotating disc, and its inner wall is provided with multiple arc-shaped columns spaced circumferentially; during the eccentric oscillation, the eccentric rotating disc compresses and cooperates with the arc-shaped columns to generate motion resistance, and drives the flywheel to rotate unidirectionally through the one-way transmission mechanism. This solution has the advantages of compact structure, smooth operation, precise resistance adjustment, and low noise.

Description

Technical Field

[0001] This utility model relates to the field of fitness equipment technology, and in particular to a fitness bike with an eccentric self-rotating flywheel structure. Background Technology

[0002] Traditional exercise bikes generally use a magnetic flywheel and belt drive structure, transmitting power through a belt pulley, pressure roller, and belt assembly. This structure has significant technical drawbacks: First, the need to install the belt drive system significantly increases the overall lateral dimensions of the machine, which not only increases the difficulty of transportation and storage but also raises warehousing costs. Second, the belt drive system is prone to problems such as misalignment, wear, and breakage during actual use. These problems not only produce unpleasant friction noises but also increase the frequency and cost of equipment maintenance. Third, the belt tension adjustment process is relatively complex, which directly affects the assembly efficiency of the production line.

[0003] To overcome the size issues associated with belt drives, existing technologies attempt to replace belt drives with eccentric self-rotating flywheels, using eccentric bearing housings to drive the flywheel to high-speed rotation. However, this approach introduces new technical problems: direct friction between high-hardness materials generates abnormal noise, affecting the user experience; eccentric motion easily causes flywheel wobbling and vibration, reducing the stability of the equipment; and simple friction resistance adjustment methods cannot provide stable resistance output, failing to meet users' needs for progressive fitness loads. Therefore, there is an urgent need for an eccentric flywheel structure solution that can simultaneously address the problems of excessive size, significant noise, unstable operation, and inaccurate resistance adjustment. Summary of the Invention

[0004] To address the aforementioned problems, the purpose of this invention is to provide an exercise bike with an eccentric self-rotating flywheel structure, which has the advantages of compact structure, smooth operation, precise resistance adjustment, and low noise.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This application provides an exercise bike with an eccentric self-rotating flywheel structure, the technical solution of which is as follows: An exercise bike with an eccentric self-rotating flywheel structure includes: a flywheel shaft, rotatably mounted on a frame; two cranks, respectively connected to the two ends of the flywheel shaft; a flywheel; characterized in that it further includes: an eccentric rotating disc, driven by the flywheel shaft to perform circumferential eccentric oscillation, the outer edge of which is provided with alternating continuous arc-shaped grooves and arc-shaped protrusions forming arc-shaped ripples along the circumference; the eccentric rotating disc is connected to the flywheel through a one-way transmission mechanism; an outer ring is fixedly disposed on the outside of the eccentric rotating disc, the inner wall of which is provided with multiple arc-shaped columns spaced apart along the circumference; the eccentric rotating disc generates motion resistance by pressing and cooperating with the arc-shaped columns during the eccentric oscillation, and drives the flywheel to rotate unidirectionally through the one-way transmission mechanism.

[0007] This technical solution uses a flywheel shaft to drive an eccentric rotating disk in a circumferential eccentric oscillation. A unidirectional transmission mechanism converts the eccentric oscillation into the unidirectional rotation of the flywheel, which provides resistance for exercise. Furthermore, this solution utilizes the arc-shaped corrugations on the outer edge of the eccentric rotating disk and the arc-shaped cylinders on the inner wall of the outer ring to form a periodic compression engagement. The reaction force generated by this periodic compression produces running resistance, allowing the user to achieve their exercise goals. Combining these two resistance methods reduces the flywheel's rotational speed, minimizing noise, wobbling, and vibration caused by high-speed rotation. The fixed outer ring and the dynamic oscillation of the eccentric rotating disk create asymmetrical contact. Continuous resistance is generated through the rolling compression between the arc-shaped corrugations and the cylinders. Compared to direct friction with traditional hard materials, this reduces noise and improves resistance stability. The alternating distribution of arc-shaped grooves and protrusions creates a gradual change in the compression contact surface, further optimizing the continuity of resistance output.

[0008] Furthermore, this application proposes a one-way transmission mechanism comprising: a one-way bearing; and an eccentric sleeve fitted onto the flywheel shaft, the eccentric sleeve comprising an eccentric portion and a central portion; wherein the flywheel is fitted onto the central portion of the eccentric sleeve via the one-way bearing, and the inner ring of the eccentric rotating disk is fitted onto the eccentric portion of the eccentric sleeve. This technical solution, by combining the one-way bearing and the eccentric sleeve, achieves decoupling of power transmission and resistance generation. The one-way bearing allows the flywheel to rotate only in one direction, avoiding interference from reverse motion and ensuring the stability of resistance output; the central portion of the eccentric sleeve is coaxially arranged with the flywheel shaft, connecting the flywheel via the one-way bearing, so that the flywheel is not affected by eccentric motion during unidirectional rotation, thereby reducing vibration. The eccentric portion of the eccentric sleeve cooperates with the inner ring of the eccentric rotating disk, converting the rotation of the flywheel shaft into the circumferential oscillation of the eccentric rotating disk, replacing traditional belt drive through mechanical linkage, and reducing the lateral space occupation. The flywheel and the eccentric rotating disk are respectively fitted onto the central and eccentric parts of the eccentric bushing, forming a split power transmission path. This ensures the stability of the flywheel's high-speed rotation and causes the eccentric rotating disk to oscillate regularly to generate resistance, thus avoiding noise generated by direct friction between high-hardness components.

[0009] Furthermore, this application also proposes a drive disc, fixed to the flywheel shaft and rotating synchronously with it; an eccentric rotating disc is connected to the drive disc via a planetary transmission assembly; the rotational motion of the drive disc is converted into the circumferential eccentric oscillation of the eccentric rotating disc through the planetary transmission assembly. This technical solution replaces the traditional belt drive structure with a planetary transmission structure through the synergistic effect of the drive disc and the planetary transmission assembly. The drive disc is fixed to the flywheel shaft to achieve synchronous rotation, avoiding the problem of increased lateral dimensions caused by belt drive. The planetary transmission assembly converts the rotational motion of the drive disc into the circumferential eccentric oscillation of the eccentric rotating disc. This motion conversion method replaces frictional contact with mechanical meshing, eliminating the defects of belt misalignment and wear, and overcoming the drawback of noise generated by direct friction of existing eccentric flywheels.

[0010] In a specific embodiment, this application proposes a planetary transmission assembly comprising: multiple first rolling elements arranged circumferentially along the drive disk and revolving with it; the eccentric rotating disk having multiple circumferentially distributed through holes, the diameter of which is larger than the diameter of the first rolling elements; each first rolling element being fitted into a rolling sleeve within the through hole, rotating around its own axis during revolution, driving the eccentric rotating disk to eccentrically oscillate circumferentially. This technical solution achieves power transmission and motion conversion through the special structure of the planetary transmission assembly. The design of arranging multiple first rolling elements circumferentially along the drive disk ensures multi-directional balance in power transmission, avoiding wobbling and jitter caused by single-point force. The through hole diameter being larger than that of the rolling elements creates a dynamic gap, allowing the rolling elements to rotate around their own axis while rolling along the sidewall of the through hole during revolution. The rolling contact between the rolling elements and the inner wall of the through hole converts the rotational kinetic energy of the drive disk into the compound eccentric oscillation of the eccentric rotating disk, ensuring the stability of the motion trajectory through a multi-point synchronous meshing mechanism. This planetary transmission structure, while achieving motion conversion, fundamentally solves the problem of abnormal noise caused by hard material contact by replacing traditional sliding friction with rolling friction.

[0011] Furthermore, this application also proposes that the drive disc has multiple mounting holes along the circumferential direction; the connecting shaft end of each first rolling element passes through the mounting hole and is fixed by a nut.

[0012] Furthermore, this application also proposes that it further includes a fixed disk connected to the end of the outer ring away from the eccentric rotating disk; the central through hole of the fixed disk is sleeved on the bushing section of the drive disk.

[0013] Furthermore, this application proposes that multiple second rolling elements are rotatably arranged on the inner wall of the outer ring and / or the edge of the fixed disk; the portion of the second rolling element located on the inner side of the outer ring forms an arc-shaped cylinder; the arc-shaped corrugations of the eccentric rotating disk and the second rolling elements roll and compress to generate resistance. This technical solution transforms the sliding friction between traditional hard materials into rolling friction by setting rotatable second rolling elements on the outer ring or fixed disk. Specifically, the second rolling element forms an arc-shaped cylinder that makes rolling contact with the arc-shaped corrugations of the eccentric rotating disk, generating resistance through rolling compression during eccentric oscillation. The rotatable rolling element structure effectively reduces frictional noise and running resistance, and the rolling contact between the arc-shaped corrugations and the rolling elements has more stable resistance transmission characteristics compared to planar friction. Through the continuous alternating structure design of the arc-shaped corrugations, the rolling elements form a periodically gradually changing contact area during compression, thereby achieving a smooth transition in resistance output. This cooperation mechanism between the rolling elements and the corrugated structure avoids the abnormal noise problem caused by direct friction between hard materials and improves the linearity of resistance adjustment through geometric matching.

[0014] Furthermore, this application also proposes that the center arc length distance between adjacent arc-shaped grooves is substantially equal to the center arc length distance between adjacent circular arc-shaped cylinders.

[0015] Furthermore, this application also proposes that the radius of curvature of the arc groove is greater than the radius of curvature of the arc-shaped cylinder, forming a progressive extrusion contact surface.

[0016] Furthermore, this application also proposes that it further includes a fixedly mounted bearing housing; the flywheel shaft is rotatably mounted on the bearing housing via a bearing; and the fixed disc is fixed to the bearing housing by bolts.

[0017] As can be seen from the above, the exercise bike and its transmission components with an eccentric self-rotating flywheel structure provided by this application generate resistance through the rolling and squeezing cooperation between the eccentric rotating disc and the outer wheel ring. Combined with the one-way transmission mechanism, the flywheel is driven in one direction, which effectively reduces the lateral size of the equipment and avoids abnormal noise and maintenance problems caused by belt drive. At the same time, the gradual contact between the arc-shaped corrugations and the rolling elements achieves smooth resistance output. It has the advantages of compact structure, smooth operation, precise resistance adjustment and low noise. Attached Figure Description

[0018] Figure 1 This is a side view of an eccentric self-rotating flywheel structure on an exercise bike.

[0019] Figure 2 for Figure 1 AA sectional view.

[0020] Figure 3 for Figure 2 A three-dimensional view of the cross-section.

[0021] Figure 4 This is an exploded view of an eccentric self-rotating flywheel structure on an exercise bike.

[0022] Figure 5 This is a schematic diagram of an eccentric self-rotating flywheel. Detailed Implementation

[0023] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0024] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. 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. Therefore, they should not be construed as limitations on this utility model.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.

[0026] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0027] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0028] Traditionally, the fitness equipment industry has long relied on belt drives for power transmission. This structure significantly increases the lateral dimensions of the equipment, leading to high transportation and storage costs. Belt assemblies in traditional transmission methods are susceptible to periodic wear and breakage, requiring frequent tension adjustments for maintenance, further increasing operating costs. With the increasing popularity of home fitness, the market demand for compact equipment continues to grow. However, existing eccentric flywheel solutions generate abnormal noise due to direct friction between moving parts, and dynamic wobbling reduces equipment stability. Furthermore, the simple friction structure cannot achieve linear resistance adjustment, hindering improvements in user experience.

[0029] To address the aforementioned issues, designers considered the space requirements and maintenance limitations of belt drive systems and attempted to reduce size by using a direct drive method with rotating components. Analysis of the abnormal noise sources from the eccentric flywheel revealed that the excessively high coefficient of friction at the contact surface of the high-hardness material was the primary cause. To resolve the resistance fluctuation problem, the research team proposed transforming continuous contact into periodic rolling compression, utilizing the wave-shaped contact surface 50 to achieve gradual resistance changes. After multiple structural optimizations, a composite resistance generation mechanism of the eccentric rotating disk 5 and the outer ring 6 was finally formed, combined with a unidirectional transmission mechanism to achieve unidirectional kinetic energy conversion.

[0030] like Figure 1-5As shown, this embodiment proposes an exercise bike with an eccentric self-rotating flywheel structure, including a flywheel shaft 1 rotatably mounted on the frame, a transmission structure with cranks 3 connected to both ends, and a flywheel 4 mounted on the flywheel shaft 1. The improved part includes an eccentric rotating disk 5 driven by the flywheel shaft 1, whose outer edge is provided with alternating continuous arc-shaped grooves 53 and arc-shaped protrusions 52 forming arc-shaped corrugations 50. This rotating disk 5 is connected to the flywheel 4 through a one-way transmission mechanism. The inner wall of the outer wheel ring 6, fixed on the outer side, is provided with circumferentially spaced arc-shaped columns 7. During the oscillation process, the eccentric rotating disk 5 compresses against the columns 7, generating motion resistance, while simultaneously driving the flywheel 4 to rotate unidirectionally through the one-way transmission. The circumferential eccentric oscillation refers to the radial offset motion generated by the rotating disk 5 while revolving around the flywheel shaft 1, which can be achieved through a planetary gear set or a crank-connecting rod mechanism. The alternating continuous structure of the arc-shaped corrugations 50 forms a periodic contact surface. The radius of curvature of each arc-shaped groove 53 can be larger than the radius of curvature of the corresponding column 7, forming a contact trajectory that deepens from shallow to deep. The circumferential spacing of the arc-shaped columns 7 of the outer ring 6 matches the spacing between the crests and troughs of the arc-shaped corrugations 50, ensuring a uniform distribution of contact points. The one-way transmission mechanism includes a ratchet or overrunning clutch, allowing the eccentric rotating disk 5 to drive the flywheel 4 to rotate only during a specific oscillation phase. During use, when the user pedals the crank 3 to rotate the flywheel shaft 1, the eccentric rotating disk 5 is driven to generate a compound motion. The arc-shaped corrugations 50 on the outer edge of the rotating disk 5 make rolling contact with the columns 7 on the inner wall of the outer ring 6, generating periodically changing compression resistance during the oscillation. In each compression cycle, the contact area between the arc-shaped grooves 53 and the columns 7 gradually increases, forming a progressive increase in resistance. The one-way transmission mechanism converts the oscillating motion into the one-way rotation of the flywheel 4. This structure replaces belt drive with mechanical contact, eliminating the need for lateral space, while the rolling compression method significantly reduces friction noise.

[0031] Existing eccentric flywheels rely on continuous rotation to generate resistance. This design utilizes the intermittent compression of the wave-shaped contact surface 50 to achieve resistance adjustment, reducing the resistance required by the flywheel 4, thereby reducing its speed and effectively eliminating motion jitter. Compared to planar friction, the rolling contact between the arc-shaped corrugations 50 and the column 7 reduces the wear rate of the contact surface and extends the service life of key components. Through the above technical solutions, this application effectively reduces the lateral dimensions of the exercise bike and eliminates maintenance problems caused by belt drives. The rolling compression resistance generation mechanism significantly reduces exercise noise, and the wave-shaped contact surface 50 design achieves a smooth resistance transition. The composite motion mechanism provides progressive training loads while ensuring structural compactness, enhancing the user's exercise experience. This design, by replacing traditional transmission methods with mechanical linkage, demonstrates significant competitive advantages in both home and commercial scenarios.

[0032] In such Figure 2-4In the illustrated scheme, the one-way transmission mechanism includes a one-way bearing 8 and an eccentric sleeve 9. The eccentric sleeve 9 is fitted onto the flywheel shaft 1 and includes an eccentric portion 91 and a central portion 92. The flywheel 4 is fitted onto the central portion 92 of the eccentric sleeve 9 via the one-way bearing 8, and the inner ring of the eccentric rotating disk 5 is fitted onto the eccentric portion 91 of the eccentric sleeve 9. The one-way bearing 8 is a bearing that allows rotation in only one direction. Specifically, it can be implemented using a roller-type one-way clutch, where the internal rollers wedge tightly with the inner and outer rings to transmit torque during forward rotation and disengage freely during reverse rotation. This structure ensures that the flywheel 4 can only rotate in one direction, avoiding interference with resistance output from reverse motion. The central portion 92 of the eccentric sleeve 9 is a sleeve section coaxially arranged with the flywheel shaft 1, which can be implemented using a stepped shaft structure, with its outer diameter interference-fitted with the inner ring of the one-way bearing 8. The centering section 92 aligns the rotation axis of the flywheel 4 with that of the flywheel shaft 1, eliminating the influence of eccentric motion on the flywheel 4; that is, the flywheel 4 rotates in a centering manner. The eccentric section 91 of the eccentric bushing 9 refers to the sleeve section whose axis deviates from the flywheel shaft 1 line. This section can be formed through eccentric turning, and its outer diameter mates with the inner ring of the eccentric rotating disk 5. The eccentric section 91 converts the rotational motion of the flywheel shaft 1 into the circumferential oscillation of the eccentric rotating disk 5, providing a power source for resistance generation.

[0033] Specifically, when the flywheel shaft 1 rotates, it drives the eccentric bushing 9 to rotate synchronously. Since the flywheel 4 is mounted on the central section 92 via a one-way bearing 8, its rotation direction is restricted to a single direction by the one-way bearing 8, and the flywheel 4 only receives power input in that direction. The eccentric section 91 of the eccentric bushing 9 drives the eccentric rotating disk 5 to produce circumferential oscillation, the amplitude of which is determined by the eccentricity. The motion paths of the flywheel 4 and the eccentric rotating disk 5 are physically isolated through a split-type sleeve structure. The flywheel 4 maintains coaxial rotation in the central section 92, while the eccentric rotating disk 5 oscillates regularly in the eccentric section 91. The one-way bearing 8 automatically locks or releases during the rotation of the flywheel 4, allowing the flywheel 4 to accumulate kinetic energy during forward pedaling and avoiding resistance interference during reverse free-spinning. Compared with existing technologies, traditional solutions use eccentric bearings to directly drive the flywheel, causing the flywheel to bear eccentric loads and resulting in vibration, and the direct friction of high-hardness metal components generates noise. This design separates power transmission from resistance generation using a split eccentric bushing 9. The flywheel 4 only bears the coaxial rotational load, while the eccentric motion is handled by an independent component, preventing the flywheel 4 from wobbling. A one-way bearing 8 replaces the traditional friction-type one-way mechanism, eliminating abnormal noise caused by sliding friction, and mechanical locking ensures smooth resistance output.

[0034] like Figure 2-4As shown, the drive disk 10 is fixed to the flywheel shaft 1 and rotates synchronously with it. The eccentric rotating disk 5 is connected to the drive disk 10 through a planetary transmission assembly. The rotational motion of the drive disk 10 is converted into the circumferential eccentric oscillation of the eccentric rotating disk 5 through the planetary transmission assembly. In a specific implementation, the planetary transmission assembly includes a plurality of first rolling elements 11 arranged circumferentially along the drive disk 10 and revolving with the drive disk 10. The disk body of the eccentric rotating disk 5 is provided with a plurality of circumferentially distributed through holes 51, and the diameter of the through holes 51 is larger than the diameter of the first rolling elements 11. Each first rolling element 11 is fitted into the through hole 51 and rotates around its own axis during the revolution, and rolls along the inner wall of the through hole 51 to drive the eccentric rotating disk 5 to circumferentially eccentrically oscillate.

[0035] The drive disk 10 refers to a disc structure that rotates synchronously with the flywheel shaft 1. Specifically, it can be fixedly connected by a metal disc body with a keyway, welding, or a tight fit. It has mounting holes 100 distributed circumferentially for assembling the planetary transmission assembly. This rigid connection replaces the belt drive structure, avoiding an increase in lateral dimensions. The planetary transmission assembly is a mechanical transmission mechanism that converts rotational motion into eccentric oscillation. Specifically, it can be implemented using a structure where rolling elements 11 and through holes 51 cooperate. During its revolution, the rolling element 11 rotates around its own axis. The constraint effect of the sidewall of the through hole 51 on the rolling element 11 generates the motion trajectory required for eccentric oscillation. This structure replaces sliding friction with rolling contact, eliminating the source of abnormal noise. Circumferential eccentric oscillation refers to the combined motion of the eccentric rotating disk 5 in the horizontal plane, simultaneously performing circular motion and radial offset. Specifically, this can be achieved through a clearance fit between the rolling element 11 and the through hole 51 in the planetary transmission assembly. This motion converts the rotational kinetic energy of the flywheel shaft 1 into the periodic oscillation of the eccentric rotating disk 5, providing a stable power input for the subsequent resistance generation mechanism. The first rolling element 11 refers to a rolling component made of metal or ceramic material with a cylindrical outer surface. Specifically, it can be made of a bearing steel cylinder with surface hardening treatment, and its outer diameter forms a clearance fit with the inner wall of the through hole 51. The through hole 51 refers to a circular through hole opened on the eccentric rotating disk 5 body, and can be formed into a hole structure with a smooth inner wall by wire cutting.

[0036] Specifically, when the user pedals the crank 3, causing the flywheel shaft 1 to rotate, the drive disk 10 rotates synchronously with the shaft. Multiple first rolling elements 11 circumferentially mounted on the drive disk 10 then revolve. When the drive disk 10 drives the first rolling elements 11 in a circular revolution, the first rolling elements 11 exhibit two motion states within the through hole 51: on one hand, they move in a circular motion with the drive disk 10 as a whole; on the other hand, they rotate around their own axis due to the constraint of the inner wall of the through hole 51. The design of the through hole 51 having a diameter larger than that of the rolling elements 11 creates a dynamic gap between the rolling elements 11 and the hole wall, allowing the rolling elements 11 to move radially along the through hole 51 as their revolution trajectory changes. This composite motion causes each rolling element 11 to form rolling contact rather than sliding friction within the through hole 51, converting the rotational motion into eccentric oscillation through multi-point synchronous meshing. In the above scheme, because the diameter of the through hole 51 of the eccentric rotating disk 5 is larger than the diameter of the rolling elements 11, the rolling elements 11 rotate when they contact the inner wall of the through hole 51 during revolution, forming a planetary gear effect. The constraint effect of the sidewall of the through hole 51 on the rolling element 11 decomposes the pure rotational motion of the drive disk 10 into a composite motion of circumferential translation and radial offset of the eccentric rotating disk 5. This motion conversion process is accomplished through the mechanical meshing of the rolling element 11 and the through hole 51, avoiding the lateral space layout required by traditional belt drives and eliminating noise caused by sliding friction. The oscillation amplitude of the eccentric rotating disk 5 is determined by the clearance size between the through hole 51 and the rolling element 11, ensuring the smoothness of the motion conversion process.

[0037] Compared with existing technologies, traditional eccentric flywheels use a fixed eccentric bushing to directly drive the rotating disk, resulting in sliding friction noise between metal components. This solution converts sliding friction into rolling friction through the rolling contact between the rolling elements 11 and the inner wall of the through hole 51, reducing the coefficient of friction at the contact surface. In existing technologies, a single eccentric shaft structure easily causes axial runout of the flywheel, while the distributed transmission points formed by multiple rolling elements 11 in this solution can balance radial forces and suppress the jitter caused by eccentric motion. Through the above technical solution, this application effectively reduces friction noise between moving parts and eliminates flywheel runout. The dynamic cooperation between the rolling elements 11 and the through hole 51 achieves a smooth transition from rotational motion to eccentric oscillation, and the multi-point synchronous meshing mechanism ensures the stability of power transmission, forming a shock-free resistance output.

[0038] In a further specific embodiment, the drive disk 10 has multiple mounting holes 100 along its circumference. The connecting shaft ends of each first rolling element 11 pass through the mounting holes 100 and are fixed by nuts 12. The mounting holes 100 are uniformly distributed holes along the circumference of the drive disk 10, specifically through holes formed by machining, used to accommodate the connecting shaft ends of the first rolling elements 11. The number and position of these holes match the motion trajectory of the planetary transmission assembly, ensuring uniform force distribution on the rolling elements 11 during revolution. The connecting shaft ends are shaft-like components extending from both ends of the first rolling elements 11, specifically threaded rods or stepped shaft structures, which pass through the mounting holes 100 and engage with the nuts 12 to form axial constraints. This design ensures the rolling elements 11 maintain axial stability during rotation, preventing radial offset. The nut 12 fixing refers to the use of standard nuts 12 to engage and lock with the threaded section of the connecting shaft end, specifically using washers or anti-loosening adhesive, applying axial preload to eliminate assembly gaps. This method achieves a rigid connection between the rolling elements 11 and the drive disk 10, preventing relative slippage. Specifically, when the drive disk 10 rotates, the first rolling element 11 revolves synchronously with the drive disk 10 through the fit between the connecting shaft end and the mounting hole 100. The axial locking effect of the nut 12 on the connecting shaft end restricts its displacement along the axial direction, preventing loosening of the connection due to centrifugal force or inertial force. The connecting shaft end forms a clearance fit with the inner wall of the mounting hole 100, allowing the rolling element 11 to rotate around its own axis during the revolution, while the mechanical constraint of the nut 12 maintains the relative positional accuracy between the rolling element 11 and the drive disk 10. Thus, the wall surface of the through hole 51 of the eccentric rotating disk 5 and the rolling element 11 always maintain stable rolling contact, ensuring the regularity of the circumferential eccentric oscillation trajectory.

[0039] like Figure 2-4As shown, the scheme also includes a fixed disk 13, connected to the end of the outer ring 6 away from the eccentric rotating disk 5; the central through hole of the fixed disk 13 is sleeved on the bushing section of the drive disk 10 through a bearing. In a specific scheme, a fixed bearing seat 15 is also included, the flywheel shaft 1 is rotatably mounted on the bearing seat 15 through the bearing, and the fixed disk 13 is fixed to the bearing seat 15 by bolts 16. The fixed disk 13 refers to an annular plate-like structure rigidly connected to the end of the outer ring 6, which can be made using metal stamping and welding processes. Its function is to provide axial support for the outer ring 6 and constrain the swing amplitude of the eccentric rotating disk 5. The central through hole refers to a circular channel penetrating the center of the fixed disk 13, the inner diameter of which forms a clearance fit with the outer diameter of the bushing section of the drive disk 10, through which the axial positioning of the fixed disk 13 and the drive disk 10 is achieved. The sleeve section fitted onto the drive disk 10 refers to the nested assembly relationship between the central through hole of the fixed disk 13 and the cylindrical shaft section extending from the drive disk 10. This can be achieved using rolling bearings or sliding bearings, and its function is to isolate the rotational movement of the drive disk 10 from the stationary state of the fixed disk 13. The bearing housing 15 is a rigid support component used to support the rotational movement of the flywheel shaft 1. It can be made of cast iron or aluminum alloy, machined to form a base structure with bearing mounting holes. Its function is to provide stable rotational support for the flywheel shaft 1 and suppress axial movement. The flywheel shaft 1 is rotatably mounted on the bearing housing 15 via bearings, meaning that the flywheel shaft 1 and the bearing housing 15 are rotatably connected via rolling bearings or sliding bearings. This reduces rotational friction resistance and limits radial displacement of the flywheel shaft 1. The fixed disk 13 is fixed to the bearing housing 15 by bolts 16, meaning that after the fixed disk 13 is connected to the outer ring 6, it is rigidly connected to the bearing housing 15 via threaded fasteners.

[0040] Specifically, the bearing housing 15 is fixed to the main frame body by bolts or welding. After bearings are installed at both ends of the flywheel shaft 1, they are embedded in the mounting holes of the bearing housing 15 to form axial constraint. The fixed disk 13 and the outer ring 6 are connected by interference fit or welding to form a closed groove structure. This structure provides axial limit to the swing trajectory of the eccentric rotating disk 5 and suppresses lateral vibration caused by eccentric motion. The edge through hole of the fixed disk 13 is aligned with the threaded hole on the bearing housing 15 and fixed by bolts 16. The central through hole of the fixed disk 13 is sleeved with the bushing section of the drive disk 10 through a bearing. The inner ring of the bearing is interference-fitted with the bushing section, and the outer ring is clearance-fitted with the central through hole, so that the drive disk 10 maintains relative motion freedom with the fixed disk 13 when rotating. This sleeve structure ensures that the rotation center axis of the drive disk 10 is always coaxial with the fixed position of the outer ring 6, avoiding offset contact between the eccentric rotating disk 5 and the arc-shaped column 7 on the inner wall of the outer ring 6 during swing, thereby maintaining the stability of the extrusion resistance.

[0041] In a further preferred embodiment, multiple rotatable second rolling elements are provided on the inner wall of the outer ring 6 or the edge of the fixed disk 13. The portion of the second rolling element located inside the outer ring 6 forms an arc-shaped cylinder 7. The arc-shaped corrugations 50 of the eccentric rotating disk 5 roll and compress with the second rolling elements to generate resistance. The second rolling element refers to a rotatable component mounted on the edge of the outer ring 6 or the fixed disk 13, which can be implemented using ball bearings or cylindrical roller structures. Its rotational function converts sliding friction into rolling friction to reduce noise and lower resistance during the compression process. The arc-shaped cylinder 7 refers to the arc-shaped surface portion of the second rolling element that protrudes from the inner wall of the outer ring 6. This can be achieved by machining the outer contour of the rolling element into an arc shape, with its curvature matching the arc-shaped corrugations 50 to achieve progressive contact. The arc-shaped corrugations 50 refer to the alternating continuous arc-shaped grooves 53 and arc-shaped protrusions 52 structure on the outer edge of the eccentric rotating disk 5. This can be made by machining equidistantly distributed wave-shaped contours, and their alternating undulating geometry forms periodic contact with the rolling elements.

[0042] When the eccentric rotating disk 5 oscillates circumferentially, the arc-shaped corrugations 50 on its outer edge contact the second rolling element. Since the second rolling element can rotate around its own axis, the contact mode between the corrugations 50 and the rolling element changes from sliding friction to rolling friction. The alternating structure of the arc-shaped corrugations 50 causes the rolling element to sequentially contact the protrusions 52 and grooves 53 during movement, with the contact area gradually changing with the oscillation position. This rolling compression mechanism generates resistance while avoiding vibration and noise caused by direct friction between hard materials. The continuous alternating design of the corrugations 50 ensures a uniform pressure distribution on the rolling element during the contact transition phase, thus ensuring smooth resistance output. This solution, by introducing a rotatable second rolling element, optimizes the friction mode to rolling contact, significantly reducing operating noise. Simultaneously, the geometric fit between the arc-shaped corrugations 50 and the rolling element allows for a gradual transition in resistance changes, overcoming the problem of abrupt resistance changes in traditional planar friction. Through the above technical solution, this application effectively reduces frictional noise during the operation of the eccentric flywheel structure and improves the smoothness of resistance output. The rolling contact method reduces component wear and extends service life; the design of the corrugated 50 and the rolling element makes resistance adjustment more linear and improves user experience.

[0043] In the above scheme, the center arc length distance between adjacent arc-shaped grooves 53 is approximately equal to the center arc length distance between adjacent arc-shaped cylinders 7. The arc-shaped groove 53 refers to the circumferentially recessed portion on the outer edge of the eccentric rotating disk 5, which can be implemented using an arc-shaped groove structure. The arc-shaped cylinder 7 refers to the circumferentially spaced protrusions on the inner wall of the outer ring 6, which can be implemented using a cylindrical or spherical protrusion structure, and its surface can be fitted with rolling elements to reduce friction. The center arc length distance refers to the actual arc distance along the circumferential direction between the center points of adjacent structures, which can be achieved through equal angle distribution or equal arc length distribution to maintain a periodic meshing relationship. When the eccentric rotating disk 5 performs circumferential eccentric oscillation, the arc-shaped protrusions 52 on its outer edge alternately contact the arc-shaped cylinders 7. Since the center arc length distance between adjacent arc-shaped grooves 53 and arc-shaped cylinders 7 is equal, the arc-shaped protrusions 52 are always embedded in the gap between adjacent arc-shaped cylinders 7 during the oscillation process, forming a continuous rolling contact trajectory. This design makes the pressure distribution at the contact points more uniform, avoiding local stress concentration caused by abrupt changes in the contact spacing. At the same time, the periodic meshing relationship ensures that the contact process between the arc-shaped protrusion 52 and the arc-shaped column 7 is always in a predetermined phase, eliminating the impact load caused by misaligned contact in traditional structures, thereby suppressing motion vibration and friction noise.

[0044] Furthermore, the radius of curvature of the arc-shaped groove 53 is greater than that of the arc-shaped cylinder 7, forming a progressively extruding contact surface. The arc-shaped groove 53 refers to a concave arc-shaped surface structure along the circumferential direction of the outer edge of the eccentric rotating disk 5, with a radius of curvature designed to be greater than that of the arc-shaped cylinder 7 in contact. The arc-shaped cylinder 7 refers to a convex arc-shaped surface structure spaced circumferentially along the inner wall of the outer ring 6, which can be implemented using cylindrical rollers or hemispherical protrusions, with a radius of curvature smaller than that of the arc-shaped groove 53. This difference in curvature creates an asymmetrical geometric relationship when the two contact, achieving a gradual change in resistance by controlling the expansion process of the contact area. When the eccentric rotating disk 5 performs a circumferential eccentric oscillation, the contact between the arc-shaped groove 53 and the arc-shaped cylinder 7 begins in a local point contact state. Due to the larger radius of curvature of the arc-shaped groove 53, the contact point gradually slides and expands along the groove surface as the oscillation amplitude increases, and the contact area transitions from point contact to line contact. This gradual expansion process results in a linear increase in the compressive contact force throughout the motion cycle, avoiding the impact load generated at the moment of contact in traditional constant curvature structures. The gradual expansion of the contact area also disperses stress concentration zones, effectively suppressing abnormal noise caused by localized frictional vibration.

[0045] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. An exercise bike with an eccentric self-rotating flywheel structure, comprising: - Flywheel shaft (1), rotatably mounted on the frame; - Two cranks (3) are connected to the two ends of the flywheel shaft (1), respectively; - Flywheel (4), which is rolled on flywheel shaft (1); Its characteristic is that it further includes: - An eccentric rotating disk (5) is driven by a flywheel shaft (1) to oscillate circumferentially. Its outer edge is provided with an arc-shaped ripple (50) consisting of alternating continuous arc-shaped grooves (53) and arc-shaped protrusions (52) along the circumferential direction. - The eccentric rotating disk (5) is connected to the flywheel (4) through a one-way transmission mechanism; - The outer ring (6) is fixedly installed on the outside of the eccentric rotating disk (5), and its inner wall is provided with multiple arc-shaped columns (7) at intervals along the circumference; - The eccentric rotating disk (5) generates motion resistance by squeezing and engaging with the arc-shaped column (7) during the eccentric swing process, and drives the flywheel (4) to rotate in one direction through the one-way transmission mechanism.

2. The exercise bike according to claim 1, characterized in that: One-way transmission mechanisms include: One-way bearing (8) An eccentric bushing (9) is fitted onto the flywheel shaft (1). The eccentric bushing (9) includes an eccentric part (91) and a central part (92). The flywheel (4) is mounted on the center part (92) of the eccentric bushing (9) via a one-way bearing (8), and the inner ring of the eccentric rotating disk (5) is mounted on the eccentric part (91) of the eccentric bushing (9).

3. The exercise bike according to claim 1 or 2, characterized in that: It also includes a drive disc (10), which is fixed to the flywheel shaft (1) and rotates synchronously with it; -The eccentric rotating disk (5) is connected to the drive disk (10) through a planetary transmission assembly; - The rotational motion of the drive disk (10) is converted into the circumferential eccentric oscillation of the eccentric rotating disk (5) through the planetary transmission assembly.

4. The exercise bike according to claim 3, characterized in that: The planetary transmission assembly includes: - Multiple first rolling elements (11) are arranged circumferentially along the drive disk (10) and revolve with the drive disk (10); - The disc body of the eccentric rotating disk (5) is provided with multiple circumferentially distributed through holes (51); Each first rolling element (11) is nested in the through hole (51). During the revolution, it rotates around its own axis and rolls along the inner wall of the through hole (51), thereby driving the eccentric rotating disk (5) to oscillate circumferentially.

5. The exercise bike according to claim 4, characterized in that: The drive disk (10) is provided with a plurality of mounting holes (100) along the circumferential direction; The connecting shaft end of each first rolling element (11) passes through the mounting hole (100) and is fixed by a nut (12).

6. The exercise bike according to claim 3, characterized in that: It also includes a fixed disk (13) connected to the end of the outer ring (6) away from the eccentric rotating disk (5); The central through hole of the fixed disk (13) is fitted onto the bushing section of the drive disk (10) via a bearing.

7. The exercise bike according to claim 6, characterized in that: The inner wall of the outer ring (6) and / or the edge of the fixed disc (13) are provided with a plurality of second rolling elements; The portion of the second rolling element located inside the outer ring (6) constitutes the arc-shaped cylinder (7); The arc-shaped corrugations (50) of the eccentric rotating disk (5) and the second rolling element squeeze together to generate resistance.

8. The exercise bike according to claim 1 or 7, characterized in that: The center arc length distance between adjacent arc grooves (53) is equal to the center arc length distance between adjacent circular arc cylinders (7).

9. The exercise bike according to claim 1, characterized in that: The radius of curvature of the arc groove (53) is greater than the radius of curvature of the arc-shaped cylinder (7), forming a progressive extrusion contact surface.

10. The exercise bike according to claim 6, characterized in that: It also includes a fixed bearing housing (15); The flywheel shaft (1) is rotatably mounted on the bearing housing (15) via a bearing; The fixed plate (13) is fixed to the bearing seat (15) by bolts (16).

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