Flower drum sealing mechanism and flower drum assembly

Abstract

The application relates to the field of bicycles, in particular to a hub seal mechanism and a hub assembly. The hub seal mechanism comprises a first sealing ring, a first connecting part arranged on a tower base, a second sealing ring, a second connecting part arranged on a hub shell, a sliding plate arranged on the inner side of the second connecting part and sliding along the axial direction of the second sealing ring, a push plate arranged on one side of the sliding plate, a pre-tightening spring fixedly connected between the push plate and the second connecting part, an elastic skirt arranged between the second connecting part and the sliding plate, an annular air cavity formed by the elastic skirt, the second connecting part and the sliding plate, and a plurality of air inlets arranged on the circumferential side of the second connecting part. The initial compression force is provided by the pre-tightening spring, air enters the annular air cavity through the air inlets when the hub shell rotates, the elastic skirt is expanded and presses against the push plate, the second sealing ring is further compressed to compress the first sealing ring, the waterproof and breathable sleeve is protected, and dynamic sealing is realized.

Description

Technical Field

[0001] This invention relates to the field of bicycles, and more specifically to hub sealing mechanisms and hub assemblies. Background Technology

[0002] As a core component connecting the axle and spokes in a bicycle, the hub's performance and durability directly affect the overall riding experience and reliability. In actual use, hubs are constantly exposed to rain, dust, and other external pollutants; therefore, it is essential to effectively isolate external impurities and protect the internal transmission mechanism from intrusion.

[0003] However, most bicycle hubs on the market currently lack sufficient sealing between the bushing and the ratchet. The sealing structure is mostly a simple rubber ring or static contact seal, which is insufficient to cope with vibrations, micro-movements, and temperature changes during riding. This allows moisture and dust to easily seep in through the gaps, not only increasing rotational resistance and causing frequent abnormal noises, but also accelerating the wear of internal parts and shortening the hub's lifespan.

[0004] Therefore, there is a current need for hub sealing mechanisms and hub assemblies that can maintain a highly reliable dynamic seal during the relative rotation of the freehub base and the hub housing, effectively preventing rainwater, dust, and other contaminants from entering the ratchet drive area. This avoids internal wear, increased rotational resistance, and abnormal noise problems caused by seal failure, thereby improving the hub's service life and operational stability. Summary of the Invention

[0005] To address the problems existing in the prior art, a hub sealing mechanism and hub assembly are provided. An initial clamping force is provided by a pre-tensioning spring. When the hub shell rotates, air enters the annular air chamber through the air inlet, causing the elastic skirt to expand and press against the push plate, driving the second sealing ring to further press the first sealing ring. With the help of a breathable and waterproof sleeve for protection, dynamic sealing is achieved.

[0006] To address the problems of existing technologies, this invention provides a hub sealing mechanism applied between the freehub base and the hub shell. It includes a first sealing ring, a first connecting portion for mounting the first sealing ring on the freehub base, and a second sealing ring. The hub shell has a second connecting portion for mounting the second sealing ring. The first and second sealing rings abut against each other axially, forming a sealing interface. A sliding plate is slidably provided on the inner side of the second connecting portion along the axial direction of the second sealing ring. The sliding plate is fixedly connected to the second sealing ring. A push plate is provided on the side of the sliding plate away from the second sealing ring, fitting against it. A preload spring is fixedly connected between the push plate and the second connecting portion along the sliding direction of the sliding plate, for applying an axial preload force towards the first sealing ring to the second sealing ring. An elastic skirt is provided between the second connecting portion and the sliding plate. The elastic skirt, the second connecting portion, and the sliding plate together form an annular air cavity. Several air inlets communicating with the annular air cavity are opened on the periphery of the second connecting portion. During the rotation of the hub shell, the elastic skirt is deformed and expanded under air pressure, thereby applying an axial thrust towards the first sealing ring to the sliding plate.

[0007] Preferably, the outer periphery of the second connection is provided with a breathable and waterproof sleeve, which covers the outside of the air inlet and is made of a hydrophobic porous material to allow air to enter the annular air cavity while blocking liquid water and dust.

[0008] Preferably, the elastic skirt is an annular sleeve fitted around the outer periphery of the push plate. The two ends of the annular sleeve are fixedly connected to the slide plate and the second connecting part, respectively. The outer periphery of the push plate is provided with an outwardly protruding outer ring, which abuts against the inner wall of the annular sleeve.

[0009] Preferably, the inner side of the second connecting part is provided with a centrifugal element that abuts against the surface of the push plate, which is used to apply an axial component force to the push plate due to centrifugal force when the hub shell rotates.

[0010] Preferably, the centrifugal component includes an end ring and a plurality of elastic pressure plates evenly distributed along its circumference. The end ring is fixedly connected to the second connecting part and is coaxially arranged with the second sealing ring. One end of the elastic pressure plate is fixed to the end ring, and the other end is a free deformation end, which abuts against the surface of the push plate.

[0011] Preferably, the first sealing ring is rotatable about its axis, and a rotating connector is provided between the first connecting part and the first sealing ring. When the second sealing ring rotates, the first sealing ring that abuts against the second sealing ring is in a state of synchronous rotation.

[0012] Preferably, the rotary connector includes a fixed ring and a rotary ring, and a plurality of balls disposed between the two. The fixed ring is fixedly connected to the first connecting part, and the rotary ring is fixedly connected to the first sealing ring. The first sealing ring has a first sealing edge that extends axially and covers the outer periphery of the fixed ring.

[0013] Preferably, the second sealing ring has an axially extending second sealing edge that covers the outer periphery of the breathable and waterproof sleeve.

[0014] The present invention also provides a hub assembly, including a bottom bracket on which the freehub base and the hub shell are rotatably mounted, a ratchet drive mechanism between the freehub base and the hub shell, and a hub sealing mechanism disposed between adjacent end faces of the freehub base and the hub shell.

[0015] Preferably, the ratchet drive mechanism includes a ratchet ring disposed on the end face of the hub housing and a plurality of elastic pawls disposed on the opposite end face of the hub base and evenly distributed circumferentially. The elastic pawls abut against the ratchet ring to form a disengageable meshing engagement.

[0016] The advantages of this application compared to the prior art are:

[0017] 1. In this invention, the sliding plate and the push plate slide together axially in the second connecting part, and the pre-tightening spring always pushes the push plate toward the tower base to keep the second sealing ring and the first sealing ring in initial contact.

[0018] When the hub shell rotates, external air enters the annular air chamber through the air inlet. The air pressure acts on the annular bladder-type elastic skirt, causing it to expand and press against the outer ring of the push plate. This adds pneumatic thrust to the existing spring force, driving the slide plate to further press the second sealing ring. This fit ensures that the sealing interface maintains a tight seal under all operating conditions, including static, driving, and sliding. The breathable and waterproof sleeve protects the air inlet, effectively preventing contaminants from entering and improving seal durability.

[0019] 2. The present invention provides a centrifugal component consisting of an end ring and circumferentially distributed elastic pressure plates on the inner side of the second connection part. When the hub shell rotates, it opens radially under the action of centrifugal force, and the free deformation end presses the push plate, converting the centrifugal force into an axial component force pointing towards the base of the hub.

[0020] The axial force pushes the push plate, causing the slide plate and the second sealing ring to further press the first sealing ring, automatically enhancing the sealing interface adhesion under high-speed or coasting conditions. This centrifugal pressurization mechanism, in conjunction with pneumatic sealing and spring preload, achieves full-speed adaptive sealing without external energy, improving the sealing reliability of the hub at high speeds.

[0021] 3. The present invention provides a rotating connector consisting of a fixed ring, a rotating ring and balls between the first sealing ring and the tower base, so that the first sealing ring can rotate synchronously with the second sealing ring under sliding conditions, thereby eliminating the relative sliding between the two and reducing the wear of the sealing surface.

[0022] Meanwhile, the first sealing edge of the first sealing ring covers the outer periphery of the fixing ring, and the second sealing edge of the second sealing ring covers the outer periphery of the breathable and waterproof sleeve, forming a surrounding additional sealing barrier on the tower base side and the hub shell side, respectively, effectively preventing water and dust from intruding from the surrounding gaps, thereby achieving dynamic synchronous sealing while comprehensively improving the anti-pollution capability of the entire sealing mechanism. Attached Figure Description

[0023] Figure 1 This is a three-dimensional structural diagram of the hub sealing mechanism and hub assembly of the present invention.

[0024] Figure 2 This is a top view of the hub sealing mechanism and hub assembly of the present invention.

[0025] Figure 3 This is a three-dimensional exploded view of the hub sealing mechanism and hub assembly of the present invention, showing the hub shell and hub base from a first perspective.

[0026] Figure 4 This is a three-dimensional exploded view of the hub sealing mechanism and hub assembly of the present invention, showing the hub shell and hub base from a second perspective.

[0027] Figure 5 This is a three-dimensional structural cross-sectional view of the hub sealing mechanism and hub assembly of the present invention.

[0028] Figure 6 This is a planar sectional view of the hub sealing mechanism and hub assembly of the present invention.

[0029] Figure 7 This is a three-dimensional structural diagram of the hub sealing mechanism and hub assembly base and ratchet transmission mechanism of the present invention.

[0030] Figure 8 This is an exploded three-dimensional structural diagram of the hub sealing mechanism and hub assembly base and ratchet drive mechanism of the present invention.

[0031] Figure 9 This is a three-dimensional structural diagram of the hub sealing mechanism of the present invention.

[0032] Figure 10 This is an exploded three-dimensional structural diagram of the hub sealing mechanism of the present invention.

[0033] The following components are labeled in the diagram: 1. Hub base; 2. Hub shell; 3. Bottom axle; 4. Ratchet drive mechanism; 41. Ratchet ring; 42. Elastic pawl; 5. First sealing ring; 51. First connecting part; 52. First sealing edge; 6. Second sealing ring; 61. Second connecting part; 611. Breathable and waterproof sleeve; 62. Slide plate; 63. Push plate; 631. Preload spring; 632. Elastic skirt; 633. Outer ring; 64. Annular air chamber; 641. Air inlet; 65. Second sealing edge; 7. Centrifugal component; 71. End ring; 72. Elastic pressure plate; 8. Rotary connector; 81. Fixed ring; 82. Rotating ring; 83. Ball bearing. Detailed Implementation

[0034] To further understand the features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0035] See Figures 1 to 6 As shown, a hub sealing mechanism is applied between the freehub base 1 and the hub shell 2. It includes a first sealing ring 5, a first connecting portion 51 for mounting the first sealing ring 5 on the freehub base 1, and a second sealing ring 6 on the hub shell 2. The first sealing ring 5 and the second sealing ring 6 abut against each other axially, forming a sealing interface. A sliding plate 62 is provided on the inner side of the second connecting portion 61 along the axial direction of the second sealing ring 6, and the sliding plate 62 is fixedly connected to the second sealing ring 6. A push plate 63 is provided on the side of the sliding plate 62 away from the second sealing ring 6, and a preload spring 631 is fixedly connected between the push plate 63 and the second connecting portion 61 along the sliding direction of the sliding plate 62 to apply an axial preload force towards the first sealing ring 5 to the second sealing ring 6. An elastic skirt 632 is provided between the second connecting part 61 and the slide plate 62. The elastic skirt 632, the second connecting part 61, and the slide plate 62 together form an annular air cavity 64. Several air inlets 641 communicating with the annular air cavity 64 are opened on the periphery of the second connecting part 61. During the rotation of the hub shell 2, the elastic skirt 632 is deformed and expanded under air pressure, thereby applying an axial thrust to the slide plate 62 in the direction of the first sealing ring 5.

[0036] During the actual operation of the hub sealing mechanism, when the bicycle wheel starts to rotate, the hub shell 2, which is fixed to the wheel, rotates accordingly, while the freehub base 1 may be in a driving, stationary, or low-speed rotating state depending on the riding status. At this time, the second sealing ring 6 installed on the hub shell 2 and the first sealing ring 5 installed on the freehub base 1 maintain mutual contact in the axial direction, forming a dynamic sealing interface around the transmission area, which is used to prevent external water, dust and other contaminants from entering the internal ratchet transmission mechanism 4.

[0037] To ensure effective sealing under various operating conditions, an adaptive sealing mechanism integrating pneumatic and mechanical pre-tightening is implemented. On the side of the slide plate 62 away from the second sealing ring 6, the pre-tightening spring 631, installed between the push plate 63 and the second connecting part 61 along the sliding direction of the slide plate 62, is always in a compressed state, continuously applying a force towards the tower base 1 to the push plate 63, which is then transmitted to the slide plate 62. This ultimately allows the second sealing ring 6 to obtain a stable initial axial pre-tightening force, ensuring that the sealing interface maintains basic fit even in static or low-speed conditions.

[0038] As the hub housing 2 rotates with the wheel, external air is drawn into the annular air chamber 64 through the air intake 641 under the influence of the wind or rotational disturbance, increasing the air pressure inside the chamber. As the rotational speed increases, the air pressure continues to rise, acting on the inner surface of the elastic skirt 632, forcing it to deform and expand radially and axially. Since one end of the elastic skirt 632 is connected to the second connecting part 61 and the other end to the slide plate 62, its expansion deformation directly generates an additional axial thrust on the slide plate 62, also directed towards the freehub base 1. This aerodynamic thrust, superimposed on the mechanical preload provided by the preload spring 631, allows the second sealing ring 6 to press more tightly against the first sealing ring 5 during riding, especially at medium to high speeds, dynamically enhancing the sealing effect.

[0039] Even when the freehub 1 stops rotating while the hub shell 2 continues to rotate at high speed due to inertia during the coasting phase, the air intake 641 can still continuously supply air, the annular air chamber 64 maintains positive pressure, and the elastic skirt 632 continues to remain in an expanded state, thereby ensuring that the sealing force does not decrease during deceleration. The entire process requires no external energy and relies entirely on the airflow naturally generated by the wheel rotation to achieve enhanced sealing, thus extending the service life of the internal structure.

[0040] See Figure 5 and Figure 6 As shown, the outer periphery of the second connecting part 61 is provided with a breathable and waterproof sleeve 611. The breathable and waterproof sleeve 611 covers the outside of the air inlet 641 and is made of a hydrophobic porous material. It is used to allow air to enter the annular air cavity 64 while blocking liquid water and dust.

[0041] When the hub housing 2 rotates with the wheel, external air needs to enter the annular air chamber 64 inside through the air inlet 641 opened on the circumference of the second connecting part 61 to drive the elastic skirt 632 to expand and enhance the sealing force. However, if the air inlet 641 is directly exposed to the external environment, liquid water and dust can easily enter the annular air chamber 64 through the air inlet 641 in rainy or dusty conditions, which will affect the sensitivity of air pressure response and sealing performance.

[0042] To address the protection issue of the air inlets 641, a breathable and waterproof sleeve 611 is installed around the outer periphery of the second connection 61, completely covering the outer openings of all air inlets 641. Made of a hydrophobic porous material, it has numerous micron-sized interconnected pores, with pore sizes much smaller than water droplets but much larger than the free path of gas molecules, while also exhibiting strong hydrophobicity. Therefore, when the hub shell 2 rotates to generate negative pressure or an airflow, air can smoothly pass through the micropores of the breathable and waterproof sleeve 611 and flow into the annular air chamber 64 through the air inlets 641, maintaining the positive pressure required for pneumatic sealing.

[0043] When rainwater splashes down, the water cannot penetrate the micropores due to surface tension and hydrophobicity, and is effectively blocked on the outside of the breathable and waterproof sleeve 611. Similarly, dust particles, because their particle size is larger than the micropore diameter and cannot wet the material surface, are also intercepted. This ensures the normal inflation response of the annular air chamber 64 and eliminates the risk of the air inlet 641 becoming a contamination entry point.

[0044] See Figure 5 and Figure 6 As shown, the elastic skirt 632 is an annular sleeve that is fitted around the outer periphery of the push plate 63. The two ends of the annular sleeve are fixedly connected to the slide plate 62 and the second connecting part 61, respectively. The outer periphery of the push plate 63 is provided with an outwardly protruding outer ring 633, which abuts against the inner wall of the annular sleeve.

[0045] When the annular air chamber 64 is inflated, the annular bladder, which serves as the elastic skirt 632, expands due to the increase in internal air pressure, and its inner wall expands outward and closely adheres to the outer ring 633 around the push plate 63.

[0046] Since the two ends of the annular sleeve are fixed to the slide plate 62 and the second connecting part 61 respectively, the pressure generated by the expansion pushes the push plate 63 to move axially through the contact with the outer ring 633, overcoming the resistance of the pre-tightening spring 631. This causes the slide plate 62 and the second sealing ring 6 to apply additional sealing force towards the first sealing ring 5. Ultimately, this makes the second sealing ring 6 press more tightly against the first sealing ring 5, dynamically enhancing the adhesion of the sealing interface and achieving a sealing effect that adapts to the rotational speed.

[0047] See Figure 5 , Figure 6 , Figure 9 and Figure 10 As shown, the inner side of the second connecting part 61 is provided with a centrifugal member 7 that abuts against the surface of the push plate 63, which is used to apply an axial component force to the push plate 63 due to centrifugal force when the hub shell 2 rotates.

[0048] When the hub housing 2 starts to rotate with the wheel, the centrifugal component 7 installed inside it rotates together. Since the centrifugal component 7 is located inside the second connecting part 61 and keeps in contact with the surface of the push plate 63, as the rotation speed increases, the centrifugal component 7 tends to move radially outward under the action of centrifugal force.

[0049] When the centrifugal component 7 moves outward due to centrifugal force, it slides or presses along the surface of the push plate 63, thereby decomposing part of the radial centrifugal force into an axial component. This axial component acts directly on the push plate 63, pushing the push plate 63 towards the tower base 1, and then driving the second sealing ring 6 to further press the first sealing ring 5 through the slide plate 62.

[0050] Therefore, under high-speed rotation conditions, the centrifugal component 7 automatically provides additional sealing preload, which, together with the pneumatic seal and spring preload, creates a synergistic enhancement effect, ensuring that the sealing interface remains tightly fitted even under high speed or inertial gliding conditions, effectively preventing contaminants from entering.

[0051] See Figure 5 , Figure 6 , Figure 9 and Figure 10 As shown, the centrifugal component 7 includes an end ring 71 and a plurality of elastic pressure plates 72 evenly distributed along its circumference. The end ring 71 is fixedly connected to the second connecting part 61 and is coaxially arranged with the second sealing ring 6. One end of the elastic pressure plate 72 is fixed to the end ring 71, and the other end is a free deformation end. The deformation end abuts against the surface of the push plate 63.

[0052] The contact surface between the elastic pressure plate 72 and the push plate 63 has an inclined angle.

[0053] As the rotational speed increases, each elastic pressure plate 72 tends to open radially outward under the action of centrifugal force, and its free deformation end thus applies continuous radial pressure to the push plate 63. Since the contact surface between the push plate 63 and the elastic pressure plate 72 has a certain inclination angle, this radial pressure is converted into an axial component force pointing in the direction of the tower base 1, thereby pushing the push plate 63 to move axially.

[0054] The displacement of the push plate 63 causes the slide plate 62 and the second sealing ring 6 to press against the first sealing ring 5, giving the sealing interface additional adhesion under high-speed conditions. The entire process requires no external energy and relies entirely on the centrifugal effect generated by rotation to achieve adaptive sealing enhancement, effectively improving the dynamic sealing reliability of the hub under high speed or coasting conditions.

[0055] See Figure 5 , Figure 6 , Figure 9 and Figure 10As shown, the first sealing ring 5 can rotate around its axis, and a rotating connector 8 is provided between the first connecting part 51 and the first sealing ring 5. When the second sealing ring 6 rotates, the first sealing ring 5 that abuts against the second sealing ring 6 is in a state of synchronous rotation.

[0056] The freehub 1 is usually the driving component during riding, driven by the chain, while the hub shell 2 is the driven component. However, during coasting, the freehub 1 may stop or turn slowly, while the hub shell 2 continues to rotate at high speed due to the inertia of the wheel. This is the critical condition under which the seals are prone to wear.

[0057] Since the first sealing ring 5 is mounted on the first connecting part 51 of the tower base 1 via the rotating connector 8, it can rotate freely around its own axis. When the second sealing ring 6 rotates and comes into axial contact with it, the friction between the contact surfaces of the two will cause the first sealing ring 5 to rotate together with the second sealing ring 6.

[0058] Therefore, during the sliding process, even though the tower base 1 is stationary, the first sealing ring 5 can still maintain a synchronous or near-synchronous rotation with the second sealing ring 6, which greatly reduces or even eliminates the relative sliding speed between the two, thereby effectively avoiding wear on the sealing surface caused by high shear friction and improving the sealing life and reliability.

[0059] See Figure 5 , Figure 6 , Figure 9 and Figure 10 As shown, the rotating connector 8 includes a fixed ring 81 and a rotating ring 82, and a plurality of balls 83 disposed between the two. The fixed ring 81 is fixedly connected to the first connecting part 51, and the rotating ring 82 is fixedly connected to the first sealing ring 5. The first sealing ring 5 has a first sealing edge 52 that extends axially and covers the outer periphery of the fixed ring 81.

[0060] When the hub housing 2 rotates, the second sealing ring 6 connected to it rotates accordingly, and drives the first sealing ring 5 to rotate synchronously through the axial contact surface. During this process, the first sealing edge 52 provided on the first sealing ring 5 tightly covers the outer periphery of the fixing ring 81, forming an additional sealing barrier around the outside of the rotating connector 8. This effectively prevents external water, dust and other contaminants from entering the interior through the gap between the rotating connector 8 and the base 1, protecting the ball bearings 83 from contamination and wear, and ensuring the protective integrity of the entire sealing mechanism under dynamic operating conditions.

[0061] See Figure 5 and Figure 6 As shown, the second sealing ring 6 has a second sealing edge 65 that extends axially and covers the outer periphery of the breathable and waterproof sleeve 611.

[0062] To prevent external contaminants from entering the interior through the assembly gap between the breathable waterproof sleeve 611 and the hub shell 2, the second sealing ring 6 has a second sealing edge 65 that tightly wraps around the outer periphery of the breathable waterproof sleeve 611, forming a surrounding, close-fitting additional sealing barrier. This effectively blocks external water, dust, and other contaminants from entering the interior through the gap between the breathable waterproof sleeve 611 and the hub shell 2, protecting the annular air cavity 64 from contamination and ensuring the protective integrity of the entire sealing mechanism under dynamic operating conditions.

[0063] See Figures 1 to 8 As shown, the hub assembly includes a bottom shaft 3, on which the freehub base 1 and the hub shell 2 are rotatably mounted. A ratchet drive mechanism 4 is provided between the freehub base 1 and the hub shell 2. The assembly also includes the hub sealing mechanism described above, which is located between adjacent end faces of the freehub base 1 and the hub shell 2.

[0064] In the actual operation of the hub assembly, the bottom bracket 3 is installed between the bicycle rear forks as a fixed support. The freehub 1 and the hub shell 2 are rotatably fitted onto the outer periphery of the bottom bracket 3 via bearings. The freehub 1 is driven to rotate by the chain, and the power is transmitted to the hub shell 2 by means of the ratchet transmission mechanism 4 set between it and the hub shell 2, thereby driving the wheel forward.

[0065] When gliding or stopping pedaling, the hub shell 2 continues to rotate due to the wheel's inertia, while the freehub 1 may decelerate or come to a stop. At this time, the ratchet mechanism allows the two to rotate relative to each other. To prevent external water, mud, and dust from entering the interior through the gap between the freehub 1 and the hub shell 2 during this dynamic interaction, a hub sealing mechanism spans the rotation interface between the end face of the freehub 1 and the end face of the hub shell 2. The first sealing ring 5 is installed on the side of the freehub 1, and the second sealing ring 6 is installed on the side of the hub shell 2. The two seals press against each other axially to form a sealing interface, thereby protecting the internal ratchet drive mechanism 4 from contamination and wear, and ensuring the long-term smooth operation of the hub.

[0066] See Figures 3 to 8 As shown, the ratchet transmission mechanism 4 includes a ratchet ring 41 disposed on the end face of the hub housing 2 and a plurality of elastic pawls 42 disposed on the opposite end face of the hub base 1 and evenly distributed in the circumferential direction. The elastic pawls 42 abut against the ratchet ring 41 to form a disengageable meshing engagement.

[0067] During the operation of the hub assembly, the ratchet drive mechanism 4 achieves unidirectional power transmission between the freehub base 1 and the hub shell 2 through end face engagement. When the rider pedals the chain to drive the freehub base 1 to rotate forward, the elastic pawl 42 engages in the tooth groove of the ratchet ring 41, transmitting torque from the freehub base 1 to the hub shell 2, thereby driving the wheel to rotate synchronously.

[0068] When gliding, going downhill, or stopping pedaling, the hub shell 2 continues to rotate at high speed due to the inertia of the wheel, and its rotation speed exceeds that of the freehub base 1. At this time, the tooth surface of the ratchet ring 41 will push the elastic pawl 42 to undergo elastic deformation and slide out of the tooth groove, so that the elastic pawl 42 can spin freely on the tooth surface, thereby allowing the hub shell 2 to rotate freely relative to the freehub base 1 without resistance.

[0069] This invention provides static foundation clamping force through a pre-tension spring 631. When the hub shell 2 rotates, external air enters the annular air chamber 64 through the air inlet 641, causing the annular bladder-type elastic skirt 632 to expand and press against the outer ring 633 of the push plate 63, thus superimposing pneumatic thrust. Simultaneously, the centrifugal component 7 expands radially at high speed, and its elastic pressure plate 72 presses against the push plate 63, converting centrifugal force into axial component force, further enhancing the sealing adhesion. A tight seal at the interface can be dynamically maintained under driving, gliding, or high-speed conditions without external energy.

[0070] Furthermore, the first sealing ring 5 rotates synchronously with the second sealing ring 6 via the rotating connector 8, eliminating relative sliding wear. Together with the first sealing edge 52 covering the fixing ring 81 and the second sealing edge 65 covering the outer periphery of the breathable and waterproof sleeve 611, a double additional sealing barrier is formed, effectively preventing water and dust from intruding from surrounding gaps and improving the reliability and protective integrity of the hub sealing mechanism.

[0071] The above embodiments only illustrate one or more implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of protection of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A hub sealing mechanism, used between the hub base and the hub shell, characterized in that, include: A first sealing ring is provided on the tower base for installing the first sealing ring; The second sealing ring is provided on the hub housing for installing the second sealing ring; The first sealing ring and the second sealing ring abut against each other in the axial direction to form a sealing interface; The inner side of the second connecting part is provided with a sliding plate along the axial direction of the second sealing ring, and the sliding plate is fixedly connected to the second sealing ring; A push plate is provided on the side of the slide away from the second sealing ring, and a pre-tensioning spring is fixedly connected between the push plate and the second connecting part along the sliding direction of the slide plate, for applying an axial pre-tensioning force toward the first sealing ring to the second sealing ring; An elastic skirt is provided between the second connecting part and the slide plate. The elastic skirt, the second connecting part and the slide plate together form an annular air cavity. Several air inlets communicating with the annular air cavity are opened on the periphery of the second connecting part. During the rotation of the hub shell, the elastic skirt is deformed and expanded under air pressure, thereby applying an axial thrust to the skateboard in the direction of the first sealing ring.

2. The hub sealing mechanism according to claim 1, characterized in that, The outer periphery of the second connecting part is provided with a breathable and waterproof sleeve. The breathable and waterproof sleeve covers the outside of the air inlet and is made of hydrophobic porous material. It is used to allow air to enter the annular air cavity while blocking liquid water and dust.

3. The hub sealing mechanism according to claim 2, characterized in that, The elastic skirt is an annular sleeve that is fitted around the outer periphery of the push plate. The two ends of the annular sleeve are fixedly connected to the slide plate and the second connecting part, respectively. The outer periphery of the push plate has an outwardly protruding outer ring that abuts against the inner wall of the annular sleeve.

4. The hub sealing mechanism according to claim 1, characterized in that, The inner side of the second connecting part is provided with a centrifugal element that abuts against the surface of the push plate, which is used to apply an axial component force to the push plate due to centrifugal force when the hub shell rotates.

5. The hub sealing mechanism according to claim 4, characterized in that, The centrifugal component includes an end ring and several elastic pressure plates evenly distributed along its circumference. The end ring is fixedly connected to the second connecting part and is coaxially arranged with the second sealing ring. One end of the elastic pressure plate is fixed to the end ring, and the other end is a free deformation end. The deformation end abuts against the surface of the push plate.

6. The hub sealing mechanism according to claim 1, characterized in that, The first sealing ring is rotatable around its axis. A rotating connector is provided between the first connecting part and the first sealing ring. When the second sealing ring rotates, the first sealing ring that abuts against the second sealing ring is in a state of synchronous rotation.

7. The hub sealing mechanism according to claim 6, characterized in that, The rotating connector includes a fixed ring and a rotating ring, and a plurality of balls disposed between the two. The fixed ring is fixedly connected to the first connecting part, and the rotating ring is fixedly connected to the first sealing ring. The first sealing ring has a first sealing edge that extends axially and covers the outer periphery of the fixed ring.

8. The hub sealing mechanism according to claim 2, characterized in that, The second sealing ring has an axially extending second sealing edge that covers the outer periphery of the breathable and waterproof sleeve.

9. A hub assembly, comprising a bottom bracket, on which the freehub base and the hub shell are rotatably mounted, and a ratchet drive mechanism is provided between the freehub base and the hub shell, characterized in that, It also includes a hub sealing mechanism as described in any one of claims 1-8, the hub sealing mechanism being disposed between adjacent end faces of the hub base and the hub housing.

10. The hub assembly according to claim 9, characterized in that, The ratchet drive mechanism includes a ratchet ring disposed on the end face of the hub housing and a plurality of elastic pawls disposed on the opposite end face of the hub base and evenly distributed circumferentially. The elastic pawls abut against the ratchet ring to form a disengageable meshing engagement.

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