Hydraulic chainring assembly and bicycle
By designing a hydraulic chainring assembly, the position adjustment of the piston-driven bushing and chainring is achieved, thus solving the problems of energy waste and wear caused by the chain angle, enabling efficient cycling and extending the service life of the bicycle.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUNAN SUAO TECH CO LTD
- Filing Date
- 2025-06-27
- Publication Date
- 2026-06-30
AI Technical Summary
When shifting gears on a traditional multi-speed bicycle, the angle between the chain and the chainring causes the chain's driving force to be ineffectively dissipated, affecting riding efficiency and making it prone to chain slippage, chain wear and deformation, thus reducing the bicycle's lifespan.
The hydraulic sprocket assembly is used. The central shaft drives the bushing and sprocket to rotate, and the piston drives the bushing to slide along the central shaft to adjust the position of the sprocket to reduce the included angle. The hydraulic oil in the hydraulic chamber lubricates the bearing, so as to achieve smooth and precise movement of the sprocket.
It improves riding efficiency, reduces chain slippage and tooth wear, extends the lifespan of bicycles, has a simple structure, is easy to drive, and has good lubrication.
Smart Images
Figure CN224427714U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of bicycle technology, and in particular to a hydraulic chainring assembly and a bicycle. Background Technology
[0002] In traditional multi-speed bicycles, when shifting gears, the chain moves between different levels on the freewheel. When an angle forms between the end of the chain that wraps around the freewheel and the end that wraps around the chainring, it causes the chain to be pulled at an angle. This results in ineffective dissipation of the chain's driving force along the bottom bracket axis, significantly weakening the chain's transmission efficiency and affecting the rider's riding efficiency. In addition, the chain pulling at an angle can also easily lead to uneven shifting, chain slippage, asymmetrical wear of the teeth, and tooth deformation. This not only affects the rider's riding experience but also reduces the lifespan of the bicycle. Utility Model Content
[0003] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes a hydraulic chainring assembly, in which the bottom bracket can drive the chainring on the bushing to rotate when it rotates, the piston is connected to the bushing, and the piston can drive the chainring on the bushing to move when it slides, so that the chainring can adjust its position according to the changes of bicycle gears, and the first bearing used to support the bushing is located in the hydraulic chamber, which makes the lubrication of the first bearing more convenient and effective.
[0004] This application also proposes a bicycle having the aforementioned hydraulic chainring assembly.
[0005] A hydraulic crankset assembly according to a first aspect of this application includes a hydraulic cylinder, a bottom bracket, a bushing, a crankset, and a first bearing. The hydraulic cylinder includes a cylinder body and a piston. The cylinder body is mounted on a vehicle frame. The bottom bracket is rotatably mounted in the cylinder body, with both ends of the bottom bracket extending out of the cylinder body. The bushing is fitted onto the bottom bracket and can slide along the axial direction of the bottom bracket. The bushing and the bottom bracket are relatively fixed to each other in the circumferential direction of the bottom bracket. A hydraulic cavity is formed between the inner circumferential wall of the cylinder body and the outer circumferential wall of the bushing. The piston is slidably mounted in the hydraulic cavity along the axial direction of the bottom bracket and is connected to the bushing. The crankset is connected to one end of the bushing. The first bearing is mounted in the hydraulic cavity and fitted onto the bushing.
[0006] The hydraulic crank assembly according to the embodiments of this application has at least the following beneficial effects:
[0007] In this application, the bottom bracket is installed inside the cylinder and is fixed circumferentially to the bushing. The piston is connected to the bushing. When the pedal drives the bottom bracket to rotate, the bottom bracket drives the bushing to rotate, and the bushing in turn drives the chainring to rotate. When the bicycle freewheel shifts gears, the hydraulic cylinder can drive the piston to slide. The piston can then drive the chainring on the bushing to move axially along the bottom bracket, allowing the chainring to adapt its position to the changes in the bicycle gears. This effectively reduces the angle between the chain and the chainring, as well as the angle between the chain and the freewheel, thereby improving the rider's riding efficiency. Furthermore, because the angle is smaller, the meshing range between the chain and the chainring or freewheel teeth is wider, reducing chain slippage, asymmetrical wear on the teeth, and axial stress on the teeth, which helps reduce tooth deformation and thus extends service life. Furthermore, in this application, the crankset movement is actively driven by the sliding piston. Compared to shifting gears via a chain, the crankset movement in this application is smoother and more precise, reducing the likelihood of jamming. Moreover, once in the correct position, it remains stationary, improving riding stability. In this application, the bottom bracket and bushing are located within the cylinder body. The piston's sliding motion directly drives the crankset movement, resulting in a simple structure and convenient operation. Furthermore, the first bearing supporting the bushing is located within the hydraulic chamber. The hydraulic oil in the chamber, besides propelling the piston, also lubricates the first bearing, making lubrication more convenient and effective – a clever design.
[0008] According to some embodiments of this application, the inner peripheral wall of the cylinder is formed with an annular groove, the annular groove surrounds the bushing and forms the hydraulic cavity between the bushing and the outer peripheral wall of the bushing, the piston is annular and extends circumferentially along the bushing to divide the hydraulic cavity along the central axis to form a first cavity and a second cavity, both the first cavity and the second cavity are provided with a connecting hole for connecting an oil pipe.
[0009] According to some embodiments of this application, the inner peripheral wall of the cylinder body is provided with a first annular limiting portion and a second annular limiting portion arranged axially along the bushing. The first annular limiting portion and the second annular limiting portion extend circumferentially along the bushing and fit against the outer peripheral wall of the bushing. The annular groove is formed between the first annular limiting portion and the second annular limiting portion.
[0010] According to some embodiments of this application, one end of the bushing is connected to a detachable flange, the toothed disc is connected to the flange, the first annular limiting part is located on the side of the second annular limiting part opposite to the toothed disc, the inner peripheral wall of the cylinder protrudes to form the first annular limiting part, the second annular limiting part is detachable, and can be removed from the end of the cylinder near the toothed disc after disassembly.
[0011] According to some embodiments of this application, the piston is detachably connected to the bushing.
[0012] According to some embodiments of this application, there are two first bearings, which are respectively located at both ends of the axial direction of the hydraulic cavity.
[0013] According to some embodiments of this application, the inner peripheral wall of the bushing is provided with a keyway, the keyway passing through the end of the bushing away from the toothed disc, and the outer peripheral wall of the central shaft is provided with a key structure, the key structure being slidably installed in the keyway.
[0014] According to some embodiments of this application, the hydraulic crank assembly further includes a second bearing, which is mounted on the cylinder body at the end away from the crankcase, and the central shaft is mounted inside the second bearing; wherein, the outer peripheral wall of the central shaft forms an abutment portion, the inner peripheral wall of the cylinder body forms a step, the abutment portion and the step respectively abut against the inner and outer rings of the second bearing on the side near the crankcase, the central shaft is connected to a detachable first locking member, and the cylinder body is connected to a detachable second locking member, the first locking member and the second locking member respectively abut against the inner and outer rings of the second bearing on the side away from the crankcase.
[0015] According to some embodiments of this application, an annular recess is formed on the inner side of the end of the bushing away from the toothed disc, the annular recess extends circumferentially along the bushing, and the abutment portion can extend into the annular recess when the bushing slides toward the second bearing.
[0016] The bicycle according to a second aspect of this application includes the hydraulic chainring assembly described in the first aspect of the present application.
[0017] The bicycle according to the embodiments of this application has at least the following beneficial effects:
[0018] The hydraulic chainring assembly according to the first aspect of this application has a bottom bracket installed inside a hydraulic cylinder. When the bottom bracket rotates, it drives the chainring on the bushing to rotate. A piston is connected to the bushing; when the piston slides, it drives the chainring on the bushing to move, allowing the chainring to adjust its position according to changes in bicycle gears. The structure is simple and the drive is convenient. Furthermore, the first bearing supporting the bushing is located within the hydraulic chamber. The hydraulic oil in the chamber, in addition to driving the piston, can also lubricate the first bearing, making lubrication more convenient and effective—a clever design.
[0019] Additional aspects and advantages of this application will be set forth in part in the description which follows, and some of these additional aspects and advantages will become apparent from the description or may be learned by practice of this application. Attached Figure Description
[0020] The present application will be further described below with reference to the accompanying drawings and embodiments, wherein:
[0021] Figure 1 This is a schematic diagram illustrating the connection between a traditional chainring and a freewheel.
[0022] Figure 2 This is a schematic diagram illustrating the fit between the chainring and the freewheel in this application;
[0023] Figure 3 This is a schematic diagram of the overall structure of the hydraulic crank assembly of this application;
[0024] Figure 4 This is a cross-sectional view of the hydraulic crank assembly of this application;
[0025] Figure 5 for Figure 4 A magnified view of the area where the first annular limiting part is located;
[0026] Figure 6 for Figure 4 A magnified view of the area where the second bearing is located.
[0027] Icon labels:
[0028] Hydraulic cylinder 100; cylinder body 101; piston 102; hydraulic chamber 103; first chamber 104; second chamber 105; oil pipe 106; first annular limiting part 107; second annular limiting part 108; step 109; first locking member 110; second locking member 111; servo hydraulic station 112; third locking member 113;
[0029] Central shaft 200; key structure 201; abutment part 202;
[0030] 300 bushing; 301 keyway; 302 annular countersunk;
[0031] Crankset 400;
[0032] First bearing 500;
[0033] Second bearing 600;
[0034] Frame 700;
[0035] Position detection unit 800; magnetic ring 801; displacement sensor 802;
[0036] Flywheel 900. Detailed Implementation
[0037] The embodiments of this application are described in detail below. Examples of the 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 are only used to explain this application, and should not be construed as limiting this application.
[0038] In the description of this application, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0039] In the description of this application, "multiple" refers to two or more. The use of "first" and "second" is for the purpose of distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or the order in which the technical features are indicated.
[0040] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.
[0041] To better describe the hydraulic chainring assembly and bicycle of the embodiments of this application, a brief description is given here of the 400° angle change between the chain and chainring during conventional bicycle gear shifting. (Reference) Figure 1 When the chain is in the highest gear (900) on the cassette, there is a large angle θ between the chain and the chainring 400. Because of this angle θ, a significant axial component of the chain's driving force cannot be used to drive the cassette 900, resulting in energy waste. Understandably, the larger the angle θ, the more energy is wasted. This embodiment reduces energy waste by decreasing the angle θ, thereby improving riding efficiency. (Reference) Figure 2 , Figure 2 The dashed rectangle can be understood as the position of the crankset 400 before it moves, and the solid rectangle can be understood as the position of the crankset 400 after it moves. The included angle after the movement is β, which is significantly smaller than the angle θ, thus effectively reducing the axial force component.
[0042] The following is for reference. Figures 3 to 6 This application describes a hydraulic crankset assembly and a bicycle according to embodiments thereof.
[0043] like Figures 3 to 6As shown, the hydraulic crank assembly according to the first aspect of this application includes a hydraulic cylinder 100, a central shaft 200, a bushing 300, a crank 400, and a first bearing 500.
[0044] The hydraulic cylinder 100 includes a cylinder body 101 and a piston 102. The cylinder body 101 is used to mount the frame 700. The central shaft 200 is rotatably mounted in the cylinder body 101, with both ends of the central shaft 200 extending out of the cylinder body 101. The bushing 300 is sleeved on the central shaft 200 and can slide along the axial direction of the central shaft 200. The bushing 300 and the central shaft 200 are relatively fixed in the circumferential direction of the central shaft 200. A hydraulic cavity 103 is formed between the inner circumferential wall of the cylinder body 101 and the outer circumferential wall of the bushing 300. The piston 102 is slidably mounted in the hydraulic cavity 103 along the axial direction of the central shaft 200. The piston 102 is connected to the bushing 300. A toothed sprocket 400 is connected to one end of the bushing 300. A first bearing 500 is mounted in the hydraulic cavity 103 and sleeved on the bushing 300.
[0045] For example, the frame 700 may have mounting holes, and the hydraulic cylinder 100 is installed in the mounting holes. The cylinder body 101 may have a mounting cavity, and both ends of the mounting cavity may be through-holes. The bottom bracket 200 is rotatably installed in the mounting cavity of the cylinder body 101. The bottom bracket 200 may extend horizontally, and both ends of the bottom bracket 200 extend out of the cylinder body 101. The two ends of the bottom bracket 200 are used to connect cranks, and the cranks are used to install pedals. The rider rotates the cranks by pedaling, thereby driving the bottom bracket 200 to rotate.
[0046] A bushing 300 is fitted onto a central shaft 200 and can slide along the axial direction of the central shaft 200. The bushing 300 and the central shaft 200 are relatively fixed in the circumferential direction of the central shaft 200. Part of the bushing 300 is located within the mounting cavity of the cylinder body 101, and one end of the bushing 300 can extend out of the mounting cavity of the cylinder body 101. A hydraulic cavity 103 is formed between the inner circumferential wall of the mounting cavity of the cylinder body 101 and the outer circumferential wall of the bushing 300. The hydraulic cavity 103 can be annular and surrounds the bushing 300. The piston 102 can be annular and surrounds the bushing 300. The piston 102 is slidably mounted within the hydraulic cavity 103 along the axial direction of the central shaft 200. The hydraulic oil in the hydraulic cavity 103 pushes the piston 102 to slide. The piston 102 is connected to the portion of the bushing 300 located within the cylinder body 101.
[0047] The chainring 400 is connected to one end of the bushing 300. Specifically, the chainring 400 is connected to the end of the bushing 300 that extends out of the cylinder body 101. When the foot pedal drives the bottom bracket 200 to rotate, the bottom bracket 200 drives the bushing 300 to rotate, and the bushing 300 in turn drives the chainring 400 to rotate. The hydraulic cylinder 100 can drive the piston 102 to slide, and the piston 102 can drive the bushing 300 to slide along the axial direction of the bottom bracket 200. The bushing 300 can then drive the chainring 400 to move along the axial direction of the bottom bracket 200, thereby adjusting the relative position of the chainring 400 and the bottom bracket 200.
[0048] A first bearing 500 is installed inside the hydraulic chamber 103 and sleeved on the bushing 300. There can be one or two first bearings 500. The first bearing 500 supports the bushing 300, making its rotation and sliding smoother. Since the first bearing 500 is located inside the hydraulic chamber 103, the hydraulic oil in the hydraulic chamber 103, in addition to pushing the piston 102 to slide, can also directly lubricate the first bearing 500. The first bearing 500 can be a bearing without an inner ring, with the bushing 300 acting as the inner ring, thus facilitating the rotation and sliding of the bushing 300.
[0049] In this application, the bottom bracket 200 is installed inside the cylinder body 101 and is circumferentially fixed to the bushing 300. The piston 102 is connected to the bushing 300. When the pedal drives the bottom bracket 200 to rotate, the bottom bracket 200 drives the bushing 300 to rotate, and the bushing 300 in turn drives the chainring 400 to rotate. When the bicycle freewheel 900 shifts gears, the hydraulic cylinder 100 can drive the piston 102 to slide. The piston 102 can then drive the chainring 400 on the bushing 300 to move axially along the bottom bracket 200, so that the chainring 400 adapts to the changes in the bicycle gears, thereby effectively reducing the angle between the chain and the chainring 400 and the angle between the chain and the freewheel 900, thus improving the rider's riding efficiency. Furthermore, the smaller angle allows for a wider engagement range between the chain and the teeth of the chainring 400 or cassette 900, reducing chain slippage, asymmetrical tooth wear, and axial stress on the teeth, thus minimizing tooth deformation and extending service life. Additionally, in this application, the chainring 400 is actively driven to move via the sliding of the drive piston 102. Compared to the chain-driven movement of the chainring 400 during gear shifting with the cassette 900, the chainring 400 moves more smoothly and precisely, reducing the likelihood of jamming. Moreover, once in the correct position, it remains stationary, improving riding stability.
[0050] In this application, the central shaft 200 and bushing 300 are located within the cylinder body 101. When the piston 102 slides, it can directly drive the crankshaft 400 to move, resulting in a simple structure and convenient driving. Furthermore, the central shaft 200 and bushing 300 are assembled within the cylinder body 101 of the hydraulic cylinder 100, forming a single assembly structure, which is more convenient for assembly onto or disassembly from the frame 700. In addition, the first bearing 500 supporting the bushing 300 is located within the hydraulic chamber 103. The hydraulic oil in the hydraulic chamber 103, besides driving the piston 102 to slide, can also directly lubricate the first bearing 500, making lubrication more convenient and effective, without requiring additional oil passages. This results in a simpler structure, easier processing, and a clever design. Moreover, the outer peripheral wall of the bushing 300 and the inner peripheral wall of the cylinder body 101 form a hydraulic cavity 103. Compared with the traditional oil cylinder, the central shaft 200 passing through the cylinder body 101 does not need to pass through the hydraulic cavity 103, thus it will not affect the oil in the hydraulic cavity 103, nor will it affect the sealing of the hydraulic cavity 103.
[0051] It should be noted that the chainring 400 can stop at multiple gears when it moves along the axial direction of the central shaft 200, for example, three. The gears of the chainrings on both sides can correspond to multiple gears on both sides of the freewheel 900, and the gears of the chainring in the middle can correspond to multiple gears in the middle of the freewheel 900.
[0052] In some embodiments of this application, such as Figure 4 and Figure 5 As shown, an annular groove is formed on the inner peripheral wall of the cylinder body 101. The annular groove surrounds the bushing 300 and forms a hydraulic chamber 103 between it and the outer peripheral wall of the bushing 300. The piston 102 is annular and extends along the circumference of the bushing 300 to divide the hydraulic chamber 103 along the axial direction of the central shaft 200 to form a first chamber 104 and a second chamber 105. Both the first chamber 104 and the second chamber 105 are provided with connecting holes for connecting the oil pipe 106.
[0053] Two connecting holes can be connected to a servo hydraulic station 112 via an oil pipe 106, which can be equipped with a reversing valve. When the servo hydraulic station 112 injects oil into the first chamber 104 through the oil pipe 106 and extracts oil from the second chamber 105, it drives the piston 102 to slide in one direction, thereby driving the bushing 300 to slide in one direction. After the reversing valve reverses, the servo hydraulic station 112 injects oil into the second chamber 105 through the oil pipe 106 and extracts oil from the first chamber 104, thereby driving the piston 102 to slide in the opposite direction, thereby driving the bushing 300 to slide in the opposite direction. This achieves the sliding adjustment of the bushing 300, thus realizing the axial movement adjustment of the crankshaft 400 along the central shaft 200. The structure is simple, the operation is convenient, and the adjustment effect is good.
[0054] In some embodiments of this application, such as Figure 4 and Figure 5 As shown, the inner peripheral wall of the cylinder body 101 is provided with a first annular limiting part 107 and a second annular limiting part 108 arranged along the axial direction of the bushing 300. The first annular limiting part 107 and the second annular limiting part 108 extend along the circumferential direction of the bushing 300 and fit against the outer peripheral wall of the bushing 300. An annular groove is formed between the first annular limiting part 107 and the second annular limiting part 108.
[0055] In this embodiment, a first annular limiting part 107 and a second annular limiting part 108 are provided on the inner peripheral wall of the cylinder 101 to form a hydraulic cavity 103. The structure is simple, and the first annular limiting part 107 and the second annular limiting part 108 can also naturally seal the hydraulic cavity 103, resulting in better sealing.
[0056] In some embodiments of this application, such as Figure 4 and Figure 5 As shown, one end of the bushing 300 is connected to a detachable flange, the crankcase 400 is connected to the flange, the first annular limiting part 107 is located on the side of the second annular limiting part 108 away from the crankcase 400, the inner peripheral wall of the cylinder body 101 protrudes to form the first annular limiting part 107, the second annular limiting part 108 is detachable, and after disassembly, it can be removed from the end of the cylinder body 101 near the crankcase 400.
[0057] In this embodiment, the inner peripheral wall of the cylinder body 101 protrudes to form a first annular limiting part 107, meaning the cylinder body 101 and the first annular limiting part 107 are integrally formed, simplifying processing and improving sealing. In this embodiment, because the crankset 400 is relatively large, for ease of assembly and disassembly, the bushing 300 is optimally inserted and withdrawn from the end of the cylinder body 101 closest to the crankset 400. Thus, the second annular limiting part 108 is detachably connected to the cylinder body 101, facilitating the insertion and withdrawal of the bushing 300. To further facilitate the assembly and disassembly of the second annular limiting part 108, a flange is detachably connected to the bushing 300, preventing interference from the crankset 400 during assembly and disassembly, making assembly and disassembly more convenient.
[0058] In some embodiments of this application, the outer peripheral wall of the second annular limiting portion 108 is threadedly connected to the inner peripheral wall of the cylinder body 101. For example, the outer peripheral wall of the second annular limiting portion 108 is provided with an external thread, and the inner peripheral wall of the corresponding area of the cylinder body 101 is provided with an internal thread. The outer peripheral wall of the second annular limiting portion 108 and the inner peripheral wall of the cylinder body 101 are connected by the mating of the external and internal threads, which makes it more convenient to disassemble and assemble the second annular limiting portion 108.
[0059] Of course, the second annular limiting part 108 can also be engaged with the cylinder body 101.
[0060] In some embodiments of this application, such as Figure 4 and Figure 5 As shown, piston 102 is detachably connected to bushing 300. For example, the portion of piston 102 and bushing 300 located within cylinder body 101 can be snap-fit, interference fit, threaded connection, or connected by fasteners. This facilitates cleaning of piston 102, and when piston 102 wears out, it can be replaced separately without replacing other parts, resulting in lower costs.
[0061] Of course, in some other embodiments of this application, the portion of the piston 102 and the bushing 300 located inside the cylinder 101 may also be integrally formed.
[0062] In some embodiments of this application, such as Figure 4 As shown, there are two first bearings 500, which are located at opposite ends of the hydraulic chamber 103 along the axial direction. In this embodiment, there are two first bearings 500, which provides more stable support for the bushing 300 and makes the rotation and sliding of the bushing 300 smoother. The fact that the two first bearings 500 are located at opposite ends of the hydraulic chamber 103 along the axial direction can avoid interference with the sliding of the piston 102.
[0063] In some embodiments of this application, such as Figure 4 and Figure 5 As shown, the hydraulic crankset assembly also includes a position detection unit 800, which includes a magnetic ring 801 and a displacement sensor 802. The magnetic ring 801 is mounted on the piston 102 or the bushing 300 and extends circumferentially along the bushing 300. The displacement sensor 802 is mounted on the outer side of the cylinder 101 to detect the position of the magnetic ring 801. For example, the magnetic ring 801 can be mounted on the piston 102 and surround the bushing 300, and the displacement sensor 802 can be mounted on the outer peripheral wall of the cylinder 101. A control module can be provided on the frame 700. The control module can be connected to the displacement sensor 802 or to the servo hydraulic station 112.
[0064] In this embodiment, the displacement sensor 802 can sense the position of the magnetic ring 801 through magnetic induction, thereby indirectly detecting the position of the chainring 400. Based on the current gear position information of the flywheel 900 and the position of the chainring 400 detected by the displacement sensor 802, the control module controls the servo hydraulic station 112 to operate, adjusting the position of the chainring 400 to correspond to the position of the gear in the current gear position of the flywheel 900, thereby reducing the chain tilt angle.
[0065] It should be noted that the position detection unit 800 can also directly use the lidar set on the frame 700 to detect the distance between the frame 700 and the chainring 400, and then determine the position of the chainring 400 on the bottom bracket 200 through simple addition and subtraction calculations. There are various specific detection methods, which will not be elaborated here.
[0066] In some embodiments of this application, such as Figure 4 As shown, the inner circumferential wall of the bushing 300 is provided with a keyway 301, which extends axially along the bushing 300 and passes through the end of the bushing 300 away from the crankshaft 400. The outer circumferential wall of the central shaft 200 is provided with a key structure 201, which is slidably installed in the keyway 301. Along the axial direction of the bushing 300, the length of the keyway 301 is greater than the length of the key structure 201. Through the cooperation of the key structure 201 and the keyway 301, the bushing 300 and the central shaft 200 can be relatively fixed in the circumferential direction, and the bushing 300 can slide along the axial direction of the central shaft 200. The keyway 301 passes through the end of the bushing 300 away from the crankshaft 400, thus facilitating the insertion of the bushing 300 into the cylinder body 101 and also facilitating the complete removal of the bushing 300 from the cylinder body 101.
[0067] It should be noted that the bushing 300 can also have a square hole and the outer peripheral wall of part of the central shaft 200 can be square. In this way, the central shaft 200 and the bushing 300 can also be fixed relative to each other in the circumferential direction of the central shaft 200.
[0068] In some embodiments of this application, such as Figure 4 and Figure 6 As shown, the hydraulic crank assembly also includes a second bearing 600, which is installed in the cylinder 101 at the end away from the crank 400. The central shaft 200 is installed in the second bearing 600. The outer peripheral wall of the central shaft 200 has an abutment portion 202, and the inner peripheral wall of the cylinder 101 has a step 109. The abutment portion 202 and the step 109 abut against the inner and outer rings of the second bearing 600 on the side near the crank 400, respectively. The central shaft 200 is connected to a detachable first locking member 110, and the cylinder 101 is connected to a detachable second locking member 111. The first locking member 110 and the second locking member 111 abut against the inner and outer rings of the second bearing 600 on the side away from the crank 400, respectively.
[0069] For example, the first locking member 110 can be a locking nut, and the outer peripheral wall of the end of the central shaft 200 away from the crankset 400 is provided with external threads. The first locking member 110 is threadedly connected to the end of the central shaft 200 away from the crankset 400. The outer peripheral wall of the second locking member 111 can be provided with external threads, and the inner peripheral wall of the end of the cylinder body 101 away from the crankset 400 can be provided with internal threads. The second locking member 111 is threadedly connected to the end of the cylinder body 101 away from the crankset 400.
[0070] In this embodiment, the inner ring of the second bearing 600 can be completely locked by the cooperation between the abutment part 202 and the first locking member 110, and the outer ring of the second bearing 600 can be completely locked by the cooperation between the step 109 and the second locking member 111. This makes the axial positioning effect of the central shaft 200 better. Moreover, the central shaft 200 is directly supported by the first bearing 500 and indirectly supported by the second bearing 600, which also makes the installation stability better.
[0071] It should be noted that the first locking member 110 can also be snapped into the central shaft 200, and the second locking member 111 can also be snapped into the cylinder body 101.
[0072] In some embodiments of this application, such as Figure 6 As shown, an annular recess 302 is formed on the inner side of the end of the bushing 300 away from the toothed plate 400. The annular recess 302 extends circumferentially along the bushing 300. When the bushing 300 slides toward the second bearing 600, the abutment portion 202 can extend into the annular recess 302.
[0073] In this embodiment, an annular recess 302 is formed on the inner side of the end of the bushing 300 away from the toothed plate 400. When the bushing 300 slides toward the second bearing 600, the abutment portion 202 can extend into the annular recess 302. This makes the movement path of the bushing 300 longer, and thus the movement path of the toothed plate 400 longer.
[0074] In some embodiments of this application, reference is made to Figure 4 and Figure 6 As shown, the frame 700 may be provided with a third locking member 113 at both ends of the cylinder 101. The third locking member 113 limits the cylinder 101 to prevent the cylinder 101 from moving at will.
[0075] It should be noted that the third locking element 113 and the frame 700 can be connected by snap-fit or thread.
[0076] The bicycle according to a second aspect of this application includes the hydraulic chainring assembly described in the first aspect of this application.
[0077] According to the bicycle embodiments of this application, by employing the hydraulic chainring assembly of the first aspect of this application, the bottom bracket 200 is installed inside the hydraulic cylinder 100. When the bottom bracket 200 rotates, it can drive the chainring 400 on the bushing 300 to rotate. The piston 102 is connected to the bushing 300. When the piston 102 slides, it can drive the chainring 400 on the bushing 300 to move, so that the chainring 400 adjusts its position according to the changes in the bicycle gears. The structure is simple and the drive is convenient. Moreover, the first bearing 500 used to support the bushing 300 is located in the hydraulic chamber 103. The hydraulic oil in the hydraulic chamber 103 is used not only to push the piston 102 to slide, but also to lubricate the first bearing 500, making lubrication more convenient and effective. The design is ingenious.
[0078] It should be noted that since the bicycle can adopt all the technical solutions of the hydraulic chainring assembly of the first aspect embodiment, it has at least all the beneficial effects brought about by the technical solutions of the first aspect embodiment. These additional beneficial effects will not be elaborated here.
[0079] It is understood that other components and operations of the bicycle according to the embodiments of this application are known to those skilled in the art and will not be described in detail here.
[0080] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.
Claims
1. A hydraulic crankset assembly, characterized in that, include: A hydraulic cylinder, comprising a cylinder body and a piston, the cylinder body being mounted on a vehicle frame; A central shaft is rotatably mounted inside the cylinder, with both ends of the central shaft extending out of the cylinder. A bushing is fitted onto the central shaft and can slide along the axial direction of the central shaft. The bushing and the central shaft are fixed relative to each other in the circumferential direction of the central shaft. A hydraulic cavity is formed between the inner circumferential wall of the cylinder and the outer circumferential wall of the bushing. The piston is slidably installed in the hydraulic cavity along the axial direction of the central shaft. The piston is connected to the bushing. The toothed disc is connected to one end of the bushing; The first bearing is installed inside the hydraulic cavity and sleeved on the bushing.
2. The hydraulic crank assembly according to claim 1, characterized in that, The inner peripheral wall of the cylinder is formed with an annular groove, which surrounds the bushing and forms the hydraulic cavity between the bushing and the outer peripheral wall of the bushing. The piston is annular and extends circumferentially along the bushing to divide the hydraulic cavity into a first cavity and a second cavity along the axial direction of the central axis. Both the first cavity and the second cavity are provided with a connecting hole for connecting an oil pipe.
3. The hydraulic crank assembly according to claim 2, characterized in that, The inner peripheral wall of the cylinder body is provided with a first annular limiting part and a second annular limiting part arranged along the axial direction of the bushing. The first annular limiting part and the second annular limiting part extend along the circumferential direction of the bushing and fit against the outer peripheral wall of the bushing. The annular groove is formed between the first annular limiting part and the second annular limiting part.
4. The hydraulic crank assembly according to claim 3, characterized in that, One end of the bushing is connected to a detachable flange, the toothed disc is connected to the flange, the first annular limiting part is located on the side of the second annular limiting part opposite to the toothed disc, the inner peripheral wall of the cylinder protrudes to form the first annular limiting part, the second annular limiting part is detachable, and can be removed from the end of the cylinder near the toothed disc after disassembly.
5. The hydraulic crank assembly according to claim 1, characterized in that, The piston is detachably connected to the bushing.
6. The hydraulic crank assembly according to claim 1, characterized in that, There are two first bearings, which are located at opposite ends of the hydraulic chamber along its axial direction.
7. The hydraulic crank assembly according to claim 1, characterized in that, The inner peripheral wall of the bushing is provided with a keyway, which passes through the end of the bushing away from the toothed disc. The outer peripheral wall of the central shaft is provided with a key structure, which is slidably installed in the keyway.
8. The hydraulic crank assembly according to claim 1, characterized in that, Also includes: The second bearing is installed in the cylinder body at the end away from the gear ring, and the central shaft is installed in the second bearing; The outer peripheral wall of the central shaft has an abutment portion, and the inner peripheral wall of the cylinder has a step. The abutment portion and the step abut against the inner and outer rings of the second bearing on the side closest to the crankset, respectively. The central shaft is connected to a detachable first locking member, and the cylinder is connected to a detachable second locking member. The first locking member and the second locking member abut against the inner and outer rings of the second bearing on the side furthest from the crankset, respectively.
9. The hydraulic crank assembly according to claim 8, characterized in that, An annular recess is formed on the inner side of the end of the bushing away from the toothed disc. The annular recess extends circumferentially along the bushing. When the bushing slides toward the second bearing, the abutment portion can extend into the annular recess.
10. A bicycle, characterized in that, Includes the hydraulic crank assembly as described in any one of claims 1 to 9.