Piston direct drive chainring mechanism and bicycle
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-27
- Publication Date
- 2026-08-14
AI Technical Summary
[0002]自行车变速系统是自行车的重要组成，传统变速系统在骑行者切换挡位时，链条会在飞轮的不同层级间进行迁移，当链条绕设飞轮的一端与链条绕设牙盘的一端出现夹角时，会导致链条出现斜拉现象，进而导致链条的驱动力在中轴轴向上形成无效耗散，显著削弱链条的传输效能，影响骑行者的骑行效率，此外链条斜拉也容易导致换挡不平滑，出现掉链、齿部不对称的磨损以及齿部变形等问题，进而不仅影响骑行者骑行体验，而且会降低自行车使用寿命
[0007]In this application, the piston is configured as a ring structure, with the bottom bracket passing through it and fixed relative to the piston in the circumferential direction. When the pedal drives the bottom bracket to rotate, the bottom bracket drives the piston to rotate, and the piston in turn drives the chainring to rotate. When the bicycle freewheel shifts gears, the drive cylinder can drive the piston to slide along its own axis. The piston can then drive the chainring to move along the axial direction of the bottom bracket, allowing the chainring to adaptively adjust its position according 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, which can reduce chain slippage, reduce asymmetrical wear on the teeth, reduce axial force on the teeth, and help reduce tooth deformation, thus extending the service life. Furthermore, in this application, the crankset movement is actively driven by the sliding piston. Compared to shifting gears via the chain, the crankset movement in this application is smoother and more precise, reducing the occurrence of jamming. Moreover, once it reaches the corresponding position, it will not move randomly, improving riding stability. In this application, the piston can directly drive the crankset movement when sliding, and the crankset rotation is driven by the cooperation between the bottom bracket and the piston. The structure is simple, the drive is convenient, and the design is ingenious.
Smart Images
Figure CN224631872U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of bicycle technology, and in particular to a piston direct drive chainring mechanism and a bicycle. Background Technology
[0002] The bicycle derailleur system is a crucial component of a bicycle. In traditional derailleur systems, when a rider shifts gears, the chain moves between different levels on the freewheel. When the end of the chain that wraps around the freewheel forms an angle with 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 being pulled 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 piston direct-drive crankshaft mechanism, in which the central shaft is directly installed in the drive cylinder and passes through the piston. The crankshaft can be driven to rotate through the cooperation between the central shaft and the piston, and the piston sliding can directly drive the crankshaft to move. Thus, the crankshaft position can be actively adjusted during gear shifting. The structure is simple and the drive is convenient.
[0004] This application also proposes a bicycle having the aforementioned piston direct drive chainring mechanism.
[0005] According to an embodiment of the first aspect of this application, a piston direct-drive crankset mechanism includes a drive cylinder, a bottom bracket, and a crankset. The drive cylinder includes a cylinder body and a piston. The cylinder body is used to mount the crankset to the frame. The piston is slidably mounted in the cylinder body along its own axial direction and can rotate about its own axis. The piston has a through connecting hole along its axial direction. The bottom bracket is rotatably mounted in the cylinder body and passes through the connecting hole. The bottom bracket and the piston are relatively fixed in the circumferential direction of the bottom bracket. Both ends of the bottom bracket extend out of the cylinder body. The crankset is connected to one end of the piston.
[0006] The piston direct-drive crank mechanism according to the embodiments of this application has at least the following beneficial effects:
[0007] In this application, the piston is configured as a ring structure, with the bottom bracket passing through it and fixed relative to the piston in the circumferential direction. When the pedal drives the bottom bracket to rotate, the bottom bracket drives the piston to rotate, and the piston in turn drives the chainring to rotate. When the bicycle freewheel shifts gears, the drive cylinder can drive the piston to slide along its own axis. The piston can then drive the chainring to move along the axial direction of the bottom bracket, allowing the chainring to adaptively adjust its position according 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, which can reduce chain slippage, reduce asymmetrical wear on the teeth, reduce axial force on the teeth, and help reduce tooth deformation, thus extending the service life. Furthermore, in this application, the crankset movement is actively driven by the sliding piston. Compared to shifting gears via the chain, the crankset movement in this application is smoother and more precise, reducing the occurrence of jamming. Moreover, once it reaches the corresponding position, it will not move randomly, improving riding stability. In this application, the piston can directly drive the crankset movement when sliding, and the crankset rotation is driven by the cooperation between the bottom bracket and the piston. The structure is simple, the drive is convenient, and the design is ingenious.
[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 piston and forms a medium cavity with the outer peripheral wall of the piston, the outer peripheral wall of the piston protrudes to form an annular protrusion, the annular protrusion is located in the medium cavity and extends along the circumference of the piston to divide the medium 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, the connecting hole is used to connect a medium delivery pipe.
[0009] According to some embodiments of this application, the inner peripheral wall of the cylinder is provided with a first annular limiting portion and a second annular limiting portion arranged along the axial direction of the piston. The first annular limiting portion and the second annular limiting portion extend along the circumferential direction of the piston and fit against the outer peripheral wall of the piston. 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 piston is connected to a detachable flange, the toothed disc is connected to the flange, the first annular limiting portion is located on the side of the second annular limiting portion opposite to the toothed disc, the inner peripheral wall of the cylinder protrudes to form the first annular limiting portion, the second annular limiting portion 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 outer peripheral wall of the second annular limiting portion is threadedly connected to the inner peripheral wall of the cylinder body near the end of the toothed disc.
[0012] According to some embodiments of this application, the piston direct-drive crank mechanism further includes a first bearing and a second bearing. The first bearing is installed at the end of the cylinder body away from the crankcase, the central shaft is installed in the first bearing, and the second bearing is installed at the end of the cylinder body near the crankcase. The outer peripheral wall of the piston is in contact with the inner peripheral wall of the second bearing.
[0013] According to some embodiments of this application, the second bearing is located on the side of the second annular limiting portion closer to the toothed plate, and an isolation portion is provided between the second bearing and the second annular limiting portion, the isolation portion abutting against the inner ring of the second bearing.
[0014] According to some embodiments of this application, the outer peripheral wall of the central shaft is formed with an abutment portion that abuts against the side of the first bearing near the toothed plate. An annular recess is formed on the inner side of the end of the piston away from the toothed plate. The annular recess extends circumferentially along the piston. When the piston slides toward the first bearing, the abutment portion can extend into the annular recess.
[0015] According to some embodiments of this application, the drive cylinder is configured as a hydraulic cylinder.
[0016] The bicycle according to a second aspect of this application includes the piston direct drive chainring mechanism described in the first aspect of the embodiment above.
[0017] The bicycle according to the embodiments of this application has at least the following beneficial effects:
[0018] The piston direct-drive chainring mechanism of the first aspect embodiment of this application has the central shaft directly installed in the drive cylinder and passing through the piston. The chainring can be driven to rotate through the cooperation between the central shaft and the piston. The piston sliding can directly drive the chainring to move, thereby actively adjusting the chainring position during gear shifting. The structure is simple and the drive is convenient.
[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 piston direct drive crank mechanism of this application;
[0024] Figure 4 This is a partial sectional view of the piston direct drive crank mechanism of this application;
[0025] Figure 5 for Figure 4 A magnified view of the area where the first bearing is located;
[0026] Figure 6 for Figure 4 A magnified view of the area where the second bearing is located.
[0027] Icon labels:
[0028] Drive cylinder 100; cylinder body 101; piston 102; connecting hole 103; medium cavity 104; annular protrusion 105; first cavity 106; second cavity 107; first annular limiting part 108; second annular limiting part 109; annular countersunk platform 110; medium conveying pipe 111; servo hydraulic station 112; reversing valve 113; first locking member 114; second locking member 115;
[0029] Central shaft 200; Abutment part 201;
[0030] Crankset 300;
[0031] First bearing 400;
[0032] Second bearing 500;
[0033] Isolation Department 600;
[0034] Frame 700;
[0035] Flywheel 800. Detailed Implementation
[0036] The embodiments of this application 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 are only used to explain this application, and should not be construed as limiting this application.
[0037] 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.
[0038] 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.
[0039] 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.
[0040] To better describe the piston direct-drive chainring mechanism and bicycle of the embodiments of this application, a brief description is given here of the change in the 30° angle between the chain and the chainring during the conventional bicycle gear shifting process. (Reference) Figure 1 When the chain is in the highest gear (highest gear ratio) of the cassette 800, there is a large angle θ between the chain and the chainring 300. Because of this angle θ, a significant axial component of the chain's driving force cannot be used to drive the cassette 800, 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 300 before it moves, and the solid rectangle can be understood as the position of the crankset 300 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.
[0041] The following is for reference. Figures 3 to 6 This application describes a piston direct-drive chainring mechanism and a bicycle according to embodiments thereof.
[0042] like Figure 3 and Figure 4 As shown, the piston direct-drive crank mechanism according to the first aspect embodiment of this application includes a drive cylinder 100, a central shaft 200, and a crank 300.
[0043] The drive cylinder 100 includes a cylinder body 101 and a piston 102. The cylinder body 101 is used for mounting on the frame 700. The cylinder body 101 may have a mounting cavity, and both ends of the mounting cavity may be through-holes. The piston 102 is slidably mounted in the cylinder body 101 along its own axis and can rotate around its own axis. The piston 102 has a through-hole 103 along its axial direction. The central shaft 200 is rotatably mounted in the cylinder body 101 and passes through the connecting hole 103. The central shaft 200 and the piston 102 are relatively fixed in the circumferential direction of the central shaft 200. Both ends of the central shaft 200 extend out of the cylinder body 101. The chainring 300 is connected to one end of the piston 102.
[0044] For example, the drive cylinder 100 can be a hydraulic cylinder or a pneumatic cylinder. The piston 102 can be annular, and its outer peripheral wall can be cylindrical. The piston 102 is slidably mounted in the cylinder body 101 along its own axial direction and can rotate around its own axis. Specifically, the axial direction of the piston 102 can be horizontal, and one end of the piston 102 extends out of the cylinder body 101. The piston 102 has a through connecting hole 103 along its axial direction. The piston 102 is driven by a medium such as oil or gas.
[0045] The central shaft 200 is rotatably mounted inside the cylinder body 101 and passes through the connecting hole 103. The outer peripheral wall of the central shaft 200 fits against the hole wall of the connecting hole 103. The central shaft 200 can be coaxial with the piston 102. The central shaft 200 and the piston 102 are relatively fixed in the circumferential direction of the central shaft 200, but the piston 102 can slide relative to the central shaft 200 along the axial direction of the central shaft 200. Specifically, the central shaft 200 and the piston 102 can be connected by a key. In this case, along the axial direction of the central shaft 200, the keyway for installing the key is longer than the key to facilitate the sliding of the piston 102. Alternatively, the connecting hole 103 can be set as a square hole, so that the central shaft 200 and the piston 102 can be relatively fixed in the circumferential direction of the central shaft 200. The bottom bracket 200 extends out of the cylinder 101 at both ends. Crank connecting shafts can be set at both ends of the bottom bracket 200 for connecting cranks. The cranks are used to install pedals. The rider rotates the cranks by pedaling, which in turn drives the bottom bracket 200 to rotate.
[0046] The chainring 300 can be connected to one end of the piston 102 that extends out of the cylinder 101. When the foot pedal drives the bottom bracket 200 to rotate, the bottom bracket 200 drives the piston 102 to rotate, and the piston 102 in turn drives the chainring 300 to rotate. The drive cylinder 100 can drive the piston 102 to slide along its own axis, and the piston 102 can drive the chainring 300 to move along the axis of the bottom bracket 200, thereby adjusting the relative position of the chainring 300 and the bottom bracket 200.
[0047] In this application, the piston 102 is configured as a ring structure, and the central shaft 200 passes through the piston 102 and is fixed relative to the piston 102 in the circumferential direction of the central shaft 200. When the pedal drives the central shaft 200 to rotate, the central shaft 200 drives the piston 102 to rotate, and the piston 102 in turn drives the chainring 300 to rotate. When the bicycle freewheel 800 shifts gears, the drive cylinder 100 can drive the piston 102 to slide along its own axis. The piston 102 can then drive the chainring 300 to move along the axis of the central shaft 200, so that the chainring 300 can adaptively adjust its position according to the change of bicycle gears, thereby effectively reducing the angle between the chain and the chainring 300 and the angle between the chain and the freewheel 800, thus improving the rider's riding efficiency.
[0048] Furthermore, the smaller angle allows for a wider engagement range between the chain and the teeth of the chainring 300 or cassette 800, 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 300 is actively driven by the sliding piston 102. Compared to the chain-driven movement of the chainring 300 during gear shifting using the cassette 800, the chainring 300 moves more smoothly and precisely, reducing the likelihood of jamming. Moreover, once in the correct position, it remains stationary, improving riding stability.
[0049] In this application, the piston 102 can directly drive the chainring 300 to move when it slides, and can drive the chainring 300 to rotate through the cooperation of the bottom shaft 200 and the piston 102. The structure is simple, the drive is convenient, and the design is ingenious. Moreover, the bottom shaft 200 is assembled inside the drive cylinder 100, which can form an integral assembly structure, making it more convenient to assemble on or disassemble from the frame 700.
[0050] It should be noted that the chainring 300 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 800, and the gears of the chainring in the middle can correspond to multiple gears in the middle of the freewheel 800.
[0051] In some embodiments of this application, such as Figure 4 and Figure 6 As shown, an annular groove is formed on the inner peripheral wall of the cylinder 101. The annular groove surrounds the piston 102 and forms a medium cavity 104 between the annular groove and the outer peripheral wall of the piston 102. An annular protrusion 105 is formed on the outer peripheral wall of the piston 102. The annular protrusion 105 is located in the medium cavity 104 and extends along the circumference of the piston 102 to divide the medium cavity 104 into a first cavity 106 and a second cavity 107. Both the first cavity 106 and the second cavity 107 are provided with a connecting hole for connecting the medium delivery pipe 111.
[0052] Taking hydraulic oil as the medium as an example, the medium delivery pipe 111 is an oil pipe, and two connecting holes can be connected to a servo hydraulic station 112 through the medium delivery pipe 111. The medium delivery pipe 111 can be equipped with a reversing valve 113. When the servo hydraulic station 112 injects oil into the first chamber 106 through the medium delivery pipe 111 and extracts oil from the second chamber 107, it can drive the annular protrusion 105 to slide in one direction, thereby driving the piston 102 to slide in one direction. After the reversing valve 113 reverses, the servo hydraulic station 112 injects oil into the second chamber 107 through the medium delivery pipe 111 and extracts oil from the first chamber 106, thereby driving the annular protrusion 105 to slide in the opposite direction, thereby driving the piston 102 to slide in the opposite direction, thus realizing the sliding adjustment of the piston 102, thereby realizing the axial movement adjustment of the crank sprocket 300 along the central axis 200. The structure is simple, the operation is convenient, and the adjustment effect is good. Furthermore, a medium cavity 104 is formed between the outer peripheral wall of the piston 102 and the inner peripheral wall of the cylinder 101. Compared to traditional hydraulic or pneumatic cylinders, the central shaft 200 passing through the cylinder 101 does not need to pass through the medium cavity 104, thus avoiding any impact on the medium within the medium cavity 104 or its sealing. Additionally, the outer peripheral wall of the piston 102 protrudes to form an annular protrusion 105, meaning the piston 102 and the annular protrusion 105 are integrally formed, simplifying processing and improving sealing performance.
[0053] In some embodiments of this application, such as Figure 4 and Figure 6 As shown, the inner peripheral wall of the cylinder body 101 is provided with a first annular limiting part 108 and a second annular limiting part 109 arranged along the axial direction of the piston 102. The first annular limiting part 108 and the second annular limiting part 109 extend along the circumferential direction of the piston 102 and fit against the outer peripheral wall of the piston 102. An annular groove is formed between the first annular limiting part 108 and the second annular limiting part 109.
[0054] In this embodiment, a first annular limiting part 108 and a second annular limiting part 109 are provided on the inner peripheral wall of the cylinder 101 to form a medium cavity 104. The structure is simple, and the first annular limiting part 108 and the second annular limiting part 109 can also naturally seal the medium cavity 104, resulting in better sealing performance.
[0055] In some embodiments of this application, such as Figure 4 and Figure 6 As shown, one end of the piston 102 is detachably connected to a flange, the crankcase 300 is connected to the flange, the first annular limiting part 108 is located on the side of the second annular limiting part 109 away from the crankcase 300, the inner peripheral wall of the cylinder body 101 protrudes to form the first annular limiting part 108, the second annular limiting part 109 is detachably connected to the cylinder body 101, and the second annular limiting part 109 can be removed from the end of the cylinder body 101 near the crankcase 300 after disassembly.
[0056] In this embodiment, the inner peripheral wall of the cylinder body 101 protrudes to form a first annular limiting part 108, meaning the cylinder body 101 and the first annular limiting part 108 are integrally formed, simplifying processing and improving sealing. In this embodiment, since the crankshaft 300 is relatively large and the piston 102 is integrally formed with the annular protrusion 105, for ease of disassembly and assembly, it is optimal for the piston 102 to be inserted and withdrawn from the end of the cylinder body 101 closest to the crankshaft 300. Thus, the second annular limiting part 109 is detachably connected to the cylinder body 101, facilitating the insertion and withdrawal of the piston 102 from the cylinder body 101. To further facilitate the disassembly and assembly of the second annular limiting part 109, a flange is detachably connected to the piston 102, preventing the crankshaft 300 from interfering with the disassembly and assembly of the second annular limiting part 109, making disassembly and assembly even more convenient.
[0057] In some embodiments of this application, the outer peripheral wall of the second annular limiting portion 109 is threadedly connected to the inner peripheral wall of the cylinder body 101 near the end of the crankshaft 300. For example, the outer peripheral wall of the second annular limiting portion 109 is provided with an external thread, and the inner peripheral wall of the cylinder body 101 near the end of the crankshaft 300 is provided with an internal thread. The outer peripheral wall of the second annular limiting portion 109 and the inner peripheral wall of the cylinder body 101 near the end of the crankshaft 300 are threadedly connected by the mating of the external and internal threads, thus making it more convenient to assemble and disassemble the second annular limiting portion 109.
[0058] Of course, the second annular limiting part 109 can also be engaged with the cylinder body 101.
[0059] In some embodiments of this application, such as Figures 4 to 6 As shown, the piston direct drive chainring mechanism also includes a first bearing 400 and a second bearing 500. The first bearing 400 is installed in the cylinder 101 at the end away from the chainring 300, the central shaft 200 is installed in the first bearing 400, and the second bearing 500 is installed in the cylinder 101 at the end near the chainring 300. The outer peripheral wall of the piston 102 is in contact with the inner peripheral wall of the second bearing 500.
[0060] In this embodiment, the rotation of the central shaft 200 can be achieved using the first bearing 400 and the second bearing 500, satisfying the rotation requirements of the central shaft 200 and making its rotation smoother. Furthermore, the second bearing 500 can also support the piston 102, making its sliding and rotation smoother.
[0061] It should be noted that the second bearing 500 can be a bearing without an inner ring, with the piston 102 acting as the inner ring of the second bearing 500. Thus, the piston 102 and the outer ring of the second bearing 500 can rotate and slide relative to each other. A first locking member 114 can be provided on the side of the first bearing 400 and the second bearing 500 opposite to each other to lock and position the first bearing 400 and the second bearing 500. For example, there can be two first locking members 114 for locking the first bearing 400. One first locking member 114 can be threaded or snapped into the central shaft 200 to abut against the inner ring of the first bearing 400, and the other first locking member 114 can be threaded or snapped into the cylinder body 101 to abut against the outer ring of the first bearing 400. There can be only one first locking member 114 for locking the second bearing 500, which is threaded or snapped into the cylinder body 101.
[0062] In some embodiments of this application, such as Figure 4 and Figure 6 As shown, the second bearing 500 is located on the side of the second annular limiting portion 109 near the gear plate 300, and an isolation portion 600 is provided between it and the second annular limiting portion 109. The isolation portion 600 abuts against the inner ring of the second bearing 500. For example, the isolation portion 600 may be annular and sleeved on the outside of the piston 102.
[0063] In this embodiment, the second bearing 500 is located on the side of the second annular limiting part 109 closer to the gear sprocket 300, making disassembly and assembly more convenient and providing better support for the piston 102. The isolation part 600 not only simultaneously limits the second bearing 500 but also locks the second annular limiting part 109, reducing loosening of the second annular limiting part 109. Furthermore, it separates the second bearing 500 from the second annular limiting part 109, preventing the second annular limiting part 109 from interfering with the operation of the second bearing 500.
[0064] In some embodiments of this application, such as Figure 5 As shown, the outer peripheral wall of the central shaft 200 has an abutment portion 201, which abuts against the side of the first bearing 400 near the toothed plate 300. An annular recess 110 is formed on the inner side of the end of the piston 102 away from the toothed plate 300. The annular recess 110 extends circumferentially along the piston 102. When the piston 102 slides toward the first bearing 400, the abutment portion 201 can extend into the annular recess 110.
[0065] In this embodiment, an abutment portion 201 is provided to limit the first bearing 400. An annular recess 110 is formed on the inner side of the end of the piston 102 away from the toothed disc 300. When the piston 102 slides toward the first bearing 400, the abutment portion 201 can extend into the annular recess 110. This makes the movement path of the piston 102 longer, and thus the movement path of the toothed disc 300 longer. The abutment portion 201 is formed through the outer peripheral wall of the central shaft 200, which is convenient for processing.
[0066] In some embodiments of this application, the drive cylinder 100 is configured as a hydraulic cylinder. Hydraulic cylinders have strong driving force, and the drive piston 102 slides more precisely, resulting in a better effect in driving the crankset 300 to move and adjust.
[0067] It should be noted that the drive cylinder 100 can also be a pneumatic cylinder, which will not be elaborated here.
[0068] In some embodiments of this application, reference is made to Figures 4 to 6 As shown, the frame 700 may be provided with second locking members 115 at both ends of the cylinder 101. The second locking members 115 may be threaded or snapped to the frame 700. The second locking members limit the cylinder 101 to prevent the cylinder 101 from moving at will.
[0069] The bicycle according to a second aspect of this application includes the piston direct drive chainring mechanism of the first aspect of the present application.
[0070] According to the bicycle of the present application embodiment, by adopting the piston direct drive chainring mechanism of the first aspect embodiment of the present application, the bottom bracket 200 is directly installed in the drive cylinder 100 and is fitted through the piston 102. When the piston 102 slides, it can directly drive the chainring 300 to move. Through the cooperation between the bottom bracket 200 and the piston 102, the chainring 300 can be driven to rotate. This not only improves the rider's riding efficiency, but also reduces chain drop, asymmetrical wear of the teeth, and tooth deformation, thereby improving the rider's riding experience and extending the service life of the bicycle.
[0071] It should be noted that since the bicycle can adopt all the technical solutions of the piston direct drive chainring mechanism 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.
[0072] 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.
[0073] 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 piston direct drive pallet mechanism characterized by, include: A drive cylinder includes a cylinder body and a piston. The cylinder body is used to be mounted on a vehicle frame. The piston is slidably mounted in the cylinder body along its own axis and can rotate about its own axis. The piston has a through connection hole along its axial direction. A central shaft is rotatably mounted in the cylinder body and passes through the connecting hole. The central shaft and the piston are fixed relative to each other in the circumferential direction of the central shaft, and both ends of the central shaft extend out of the cylinder body. The toothed disc is connected to one end of the piston.
2. The piston direct drive pallet mechanism of claim 1, wherein, The inner peripheral wall of the cylinder is formed with an annular groove, which surrounds the piston and forms a medium cavity with the outer peripheral wall of the piston. The outer peripheral wall of the piston protrudes to form an annular protrusion, which is located in the medium cavity and extends along the circumference of the piston to divide the medium cavity into a first cavity and a second cavity along the central axis. Both the first cavity and the second cavity are provided with a connecting hole for connecting a medium delivery pipe.
3. The piston direct drive pallet mechanism of claim 2, wherein, The inner peripheral wall of the cylinder is provided with a first annular limiting part and a second annular limiting part arranged along the axial direction of the piston. The first annular limiting part and the second annular limiting part extend along the circumferential direction of the piston and fit against the outer peripheral wall of the piston. The annular groove is formed between the first annular limiting part and the second annular limiting part.
4. The piston direct-drive crank mechanism according to claim 3, characterized in that, One end of the piston 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 piston direct drive pallet mechanism of claim 4, wherein, The outer peripheral wall of the second annular limiting part is threadedly connected to the inner peripheral wall of the cylinder body near the end of the toothed disc.
6. The piston direct drive tray mechanism of claim 3, wherein, Also includes: The first bearing is installed in the cylinder body at the end away from the gear ring, and the central shaft is installed in the first bearing; The second bearing is installed in the cylinder body at one end near the toothed disc, and the outer peripheral wall of the piston is attached to the inner peripheral wall of the second bearing.
7. The piston direct drive pallet mechanism of claim 6, wherein, The second bearing is located on the side of the second annular limiting portion closer to the toothed plate, and an isolation portion is provided between it and the second annular limiting portion, the isolation portion abutting against the inner ring of the second bearing.
8. The piston direct drive pallet mechanism of claim 6, wherein, The outer peripheral wall of the central shaft has an abutment portion that abuts against the side of the first bearing near the toothed plate. An annular recess is formed on the inner side of the end of the piston away from the toothed plate. The annular recess extends circumferentially along the piston. When the piston slides toward the first bearing, the abutment portion can extend into the annular recess.
9. The piston direct drive pallet mechanism of claim 1, wherein, The drive cylinder is a hydraulic cylinder.
10. A bicycle characterized in that, Includes the piston direct drive chainring mechanism as described in any one of claims 1 to 9.