A power system for an electric-assisted bicycle and an electric-assisted bicycle

Abstract

This application belongs to the field of bicycle technology and discloses a power system for an electric-assisted bicycle and an electric-assisted bicycle. The power system includes a bottom bracket, a main output wheel, an electric speed control device, and an electric assist device. The bottom bracket is fixedly connected to the crank; the main output wheel is driven by the rear wheel; the speed control motor is coaxially driven by the speed control sun gear, and the speed control planetary gears are driven by the main output wheel; the assist motor transmits power to the speed control ring gear through the assist drive wheel and the assist transmission assembly. By independently placing the speed control motor and the speed control planetary gear mechanism relative to the bottom bracket, and independently placing the assist motor and the assist gear transmission mechanism relative to the bottom bracket, and by making the central axis of the assist drive wheel and the central axis of the assist transmission assembly not coaxial, the problem of difficulty in arranging the assist or speed control transmission gears and poor assembly processability caused by the small distance between the output shaft of the speed control motor, the output shaft of the assist motor, and the bottom bracket can be solved or alleviated, thereby improving the manufacturability and assemblability of the system.

Description

Technical Field

[0001] This application relates to the field of bicycle technology, specifically to a power system for an electric-assisted bicycle and an electric-assisted bicycle. Background Technology

[0002] Electric-assist bicycles not only offer the lightness and convenience of bicycles, but also effectively reduce the burden of riding a bicycle uphill, against the wind, or when carrying loads, thus significantly improving the rider's experience. The power system of an electric-assist bicycle typically includes sensors and an electric drive unit. Its working principle involves using sensors to detect the force applied by the rider's pedals, then determining the rider's riding intention based on the magnitude of that force, and finally controlling the electric drive unit to provide the corresponding driving force.

[0003] In related technologies, the power system of electric-assist bicycles uses a dual-motor drive. The speed-regulating motor outputs power through a planetary gear mechanism to achieve stepless speed regulation, while the assist motor outputs power through an assist gear transmission mechanism to provide assistance, thereby improving the rider's riding experience. However, in these dual-motor power systems, the central shafts of the speed-regulating planetary gear mechanism and / or the assist gear transmission mechanism are mostly located around the input shaft (pedal connection shaft). This results in a small distance between the output shafts of the speed-regulating motor, the assist motor, and the input shaft, leading to difficulties in arranging the assist or speed-regulating transmission gears and poor assembly processability.

[0004] This section provides background information related to this application, which is not necessarily prior art. Utility Model Content

[0005] The purpose of this application is to solve or at least alleviate some or all of the aforementioned problems. Therefore, the purpose of this application is to provide a power system for an electric-assisted bicycle and an electric-assisted bicycle that can solve or alleviate the problems caused by the insufficient distance between the output shaft of the speed-regulating motor, the output shaft of the assist motor, and the input shaft, resulting in difficulties in arranging the assist or speed-regulating transmission gears and poor assembly manufacturability.

[0006] To achieve the above objectives, this application adopts the following technical solution:

[0007] In a first aspect, this application provides a power system for an electric-assisted bicycle, comprising:

[0008] Bottom bracket, used for fixed connection with the bicycle crank;

[0009] The main output wheel is used to connect to the rear wheel drive of a bicycle;

[0010] An electric speed control device includes a speed-regulating motor and a speed-regulating planetary gear mechanism. The speed-regulating planetary gear mechanism includes a speed-regulating sun gear, speed-regulating planetary gears, and a speed-regulating ring gear. The speed-regulating motor is coaxially connected to the speed-regulating sun gear, and the speed-regulating planetary gears are connected to the total output gear.

[0011] An electric power assist device includes a power assist motor and a power assist gear transmission mechanism. The power assist gear transmission mechanism includes a power assist drive wheel and a power assist transmission assembly. The power assist motor is coaxially connected to the power assist drive wheel, and the output shaft of the power assist transmission assembly is connected to the speed regulating gear ring.

[0012] The speed-regulating motor and the speed-regulating planetary gear mechanism are independently external relative to the central shaft;

[0013] The power assist motor and the power assist gear transmission mechanism are independently external relative to the central shaft;

[0014] The central axis of the power-assisted drive wheel is not on the same axis as the central axis of the power-assisted transmission assembly.

[0015] As an optional solution for the power system of the electric-assisted bicycle, the power-assist transmission assembly includes a first transmission wheel and a second transmission wheel, the first transmission wheel and the second transmission wheel are connected in a driving connection, the first transmission wheel is connected in a driving connection to the power-assist drive wheel, and the second transmission wheel is connected in a driving connection to the speed-regulating gear ring.

[0016] As an optional solution for the power system of the electric-assisted bicycle, the power-assist transmission assembly includes a first transmission wheel, a second transmission wheel, and a third transmission wheel. The first transmission wheel is connected to the power-assist drive wheel, and the first transmission wheel and the third transmission wheel are coaxially and fixedly connected. The first transmission wheel has more teeth than the third transmission wheel. The third transmission wheel is connected to the second transmission wheel, and the second transmission wheel is connected to the speed-regulating gear ring.

[0017] As an optional solution for the power system of the electric-assist bicycle, a human-powered transmission component is also included. The human-powered transmission component includes a human-powered drive wheel and a human-powered driven wheel, which are connected in a driving connection. The human-powered drive wheel is coaxially connected to the bottom bracket via a first clutch, and the human-powered driven wheel is coaxially connected to the speed-regulating gear ring.

[0018] As an optional solution for the power system of the electric-assisted bicycle, the electric speed control device further includes a speed control transmission assembly, which includes a speed control drive wheel and a speed control driven wheel. The speed control drive wheel and the speed control driven wheel are connected in a driving connection. The speed control drive wheel is coaxially connected to the speed control planetary gear, and the speed control driven wheel is coaxially connected to the main output wheel.

[0019] As an optional power system for the electric-assisted bicycle, the speed-regulating driven wheel is coaxially connected to the bottom bracket via a second clutch.

[0020] As an optional solution for the power system of the electric-assist bicycle, the speed-regulating driven wheel is rotatably connected to the bottom bracket. The power system of the electric-assist bicycle also includes a housing. The speed-regulating sun gear is rotatably mounted on the housing, and a third clutch is provided between the speed-regulating sun gear and the housing. When the third clutch is engaged, the speed-regulating sun gear is relatively fixed to the housing. When the third clutch is disengaged, the speed-regulating sun gear can rotate relative to the housing.

[0021] As an optional power system for the electric-assisted bicycle, the speed-regulating driven wheel and the human-powered driving wheel are coaxially connected via a fourth clutch.

[0022] As an optional power system for the electric-assisted bicycle, the planetary gear carrier of the speed-regulating planetary gear is connected to the speed-regulating ring gear via a fifth clutch.

[0023] Secondly, this application provides an electric-assisted bicycle, including a frame and a power system for an electric-assisted bicycle as described in any of the preceding claims, wherein the power system for an electric-assisted bicycle is mounted on the frame.

[0024] The beneficial effects of this application are as follows:

[0025] The electric-assist bicycle power system provided in this application includes a bottom bracket, a main output wheel, an electric speed control device, and an electric assist device. The bottom bracket is fixedly connected to the bicycle's crank, essentially serving as the input shaft. The main output wheel is connected to the bicycle's rear wheel for drive. The electric assist device works with the electric speed control device to transmit power to the main output wheel. The electric speed control device includes a speed-regulating motor and a speed-regulating planetary gear mechanism. The speed-regulating planetary gear mechanism includes a speed-regulating sun gear, speed-regulating planetary gears, and a speed-regulating ring gear. The speed-regulating motor and the speed-regulating sun gear are coaxially connected, and the speed-regulating planetary gears are drive-connected to the main output wheel. The electric assist device includes an assist motor and an assist gear transmission mechanism. The assist gear transmission mechanism includes an assist drive wheel and an assist transmission assembly. The assist motor and the assist drive wheel are coaxially connected, and the output shaft of the assist transmission assembly is drive-connected to the speed-regulating ring gear. This power system uses an electric motor to transmit power to a speed-regulating planetary gear mechanism via an electric drive wheel and a power transmission assembly to achieve electric power assistance and reduce rider fatigue. The speed-regulating motor then transmits power to the main output wheel via the speed-regulating planetary gear mechanism to achieve continuously variable transmission and enhance the rider's riding experience.

[0026] In addition, by placing the speed-regulating motor and the speed-regulating planetary gear mechanism independently outside the central shaft, and the power-assist motor and the power-assist gear transmission mechanism independently outside the central shaft, and by placing the central shaft of the power-assist drive wheel and the central shaft of the power-assist transmission assembly not on the same axis, this power system can solve or alleviate the problems of difficulty in arranging the power-assist transmission gear mechanism and the speed-regulating gear mechanism and poor assembly processability caused by the small distance between the output shaft of the speed-regulating motor, the output shaft of the power-assist motor and the input shaft.

[0027] The electric-assisted bicycle provided in this application, by applying the aforementioned power system, can improve its manufacturability and assemblability. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this application and these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of the electric-assisted bicycle provided in the embodiments of this application.

[0030] Figure 2 This is a schematic diagram of the power system of the first example provided in the embodiments of this application.

[0031] Figure 3 This is a schematic diagram of the power system of the second example provided in the embodiments of this application.

[0032] Figure 4 This is a schematic diagram of the power system of the third example provided in the embodiments of this application.

[0033] Figure 5 This is a schematic diagram of the power system of the fourth example provided in the embodiments of this application.

[0034] Figure 6 This is a schematic diagram of the power system of the fifth example provided in the embodiments of this application.

[0035] Figure 7 This is a schematic diagram of the power system of the sixth example provided in the embodiments of this application.

[0036] Figure 8 This is a schematic diagram of the power system of the seventh example provided in the embodiments of this application.

[0037] Figure 9 This is a schematic diagram of the power system of the eighth example provided in the embodiments of this application.

[0038] Figure label:

[0039] 100. Frame; 200. Front wheel; 300. Rear wheel; 400. Crank; 500. Pedals;

[0040] 1. Central axis;

[0041] 2. Main output wheel;

[0042] 31. Speed-regulating motor;

[0043] 32. Speed-regulating planetary gear mechanism; 321. Speed-regulating sun gear; 322. Speed-regulating planetary gears; 323. Speed-regulating ring gear;

[0044] 33. Speed ​​regulating transmission assembly; 331. Speed ​​regulating drive wheel; 332. Speed ​​regulating driven wheel;

[0045] 41. Power assist motor;

[0046] 42. Power-assisted active wheel;

[0047] 43. Power steering assembly; 431. First drive wheel; 432. Second drive wheel; 433. Third drive wheel;

[0048] 5. Manual transmission components; 51. Manual drive wheel; 52. Manual driven wheel;

[0049] 61. First clutch;

[0050] 62. Second clutch;

[0051] 63. Third clutch;

[0052] 64. Fourth clutch;

[0053] 65. Fifth clutch. Detailed Implementation

[0054] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0055] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0056] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "and / or" relationship.

[0057] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0058] In this application, those skilled in the art will understand that relative terms (e.g., “about,” “approximately,” “basically,” etc.) used in conjunction with quantities or conditions are to include the values ​​and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances associated with the particular value due to manufacturing, assembly, use, etc. Such terms should also be considered as disclosing a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​not using relative terms should also be disclosed as specific values ​​with tolerances. Furthermore, “basically” when expressing relative angular relationships (e.g., substantially parallel, substantially perpendicular) may refer to a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) added to or subtracted from the indicated angle.

[0059] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0060] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.

[0061] like Figure 1 As shown, this application provides an electric-assisted bicycle, including a frame 100, a front wheel 200, a rear wheel 300, a crank 400, pedals 500, and a power system. The front wheel 200 and rear wheel 300 are rotatably mounted on the frame 100, and the power system is mounted on the frame 100. One end of the crank 400 is connected to the power system, and the other end of the crank 400 is connected to the pedals 500. When the rider pedals 500, the power system provides corresponding auxiliary power in accordance with the rider's pedaling force, so as to work together with human power to drive the rear wheel 300 to rotate, thereby propelling the electric-assisted bicycle forward.

[0062] like Figure 2 As shown, the power system includes a bottom bracket 1, a main output wheel 2, an electric speed control device, and an electric assist device. The bottom bracket 1 is fixedly connected to the bicycle crank 400, essentially serving as the input shaft. The main output wheel 2 is connected to the bicycle's rear wheel 300. The electric assist device works with the electric speed control device to transmit power to the main output wheel 2. The electric speed control device includes a speed-regulating motor 31 and a speed-regulating planetary gear mechanism 32. The speed-regulating planetary gear mechanism 32 includes a speed-regulating sun gear 321, speed-regulating planetary gears 322, and a speed-regulating ring gear 323. The speed-regulating motor 31 is coaxially connected to the speed-regulating sun gear 321, and the speed-regulating planetary gears 322 are connected to the main output wheel 2. The electric assist device includes an assist motor 41 and an assist gear transmission mechanism. The assist gear transmission mechanism includes an assist drive wheel 42 and an assist transmission assembly 43. The assist motor 41 is coaxially connected to the assist drive wheel 42, and the output shaft of the assist transmission assembly 43 is connected to the speed-regulating ring gear 323. In this power system, the power-assist motor 41 transmits power to the speed-regulating planetary gear mechanism 32 through the power-assist drive wheel 42 and the power-assist transmission component 43 to achieve electric power-assist effect and reduce rider fatigue; the speed-regulating motor 31 transmits power to the main output wheel 2 through the speed-regulating planetary gear mechanism 32 to achieve continuously variable transmission and improve the rider's riding experience.

[0063] It should be noted that the main output wheel 2 and the rear wheel 300 are connected by a chain or synchronous belt drive. For example, the main output wheel 2 can be a sprocket, such as a chainring, in which case the main output wheel 2 and the rear wheel 300 are connected by a chain drive; or, for another example, the main output wheel 2 can be a pulley, in which case the main output wheel 2 and the rear wheel 300 are connected by a synchronous belt drive.

[0064] In related technologies, the central shafts of the speed-regulating planetary gear mechanism 32 and / or the power-assisting gear transmission mechanism are mostly located around the central shaft 1, which makes the distance between the output shaft of the speed-regulating motor 31, the output shaft of the power-assisting motor 41, and the input shaft small, resulting in problems such as difficulty in arranging the power-assisting or speed-regulating transmission gears and poor assembly processability.

[0065] To solve or mitigate the above problems, the power system provided in this application has a speed-regulating motor 31 and a speed-regulating planetary gear mechanism 32 that are independently external to the central shaft 1, and an assist motor 41 and an assist gear transmission mechanism that are independently external to the central shaft 1. The central axis of the assist drive wheel 42 is not aligned with the central axis of the assist transmission assembly 43. This solves or mitigates the problem of difficulty in arranging the assist or speed-regulating transmission gears and poor assembly processability caused by the small distance between the output shaft of the speed-regulating motor 31, the output shaft of the assist motor 41, and the central shaft 1, thereby improving the manufacturability and assemblability of the power system.

[0066] like Figure 2 As shown, the main output wheel 2 is coaxially arranged with the bottom bracket 1, and the speed regulating motor 31 and the speed regulating planetary gear mechanism 32 are independently external relative to the bottom bracket 1. The power assist motor 41 and the power assist gear transmission mechanism are also independently external relative to the bottom bracket 1. The central axis of the power assist drive wheel 42 is not coaxial with the central axis of the power assist transmission assembly 43. This reduces the number of parts connected to the bottom bracket 1, allowing the bottom bracket 1 and its related parts to be compatible with external components such as the frame 100 of a regular bicycle, without the need to redesign and develop new external components such as the frame 100, thus reducing product costs.

[0067] In addition, the power system also includes sensors, including a torque sensor and a cadence magnetic ring. The torque sensor is used to collect the rider's pedaling torque, and the cadence magnetic ring is used to detect the rider's cadence data.

[0068] To transmit the rider's power, the power system also includes a manual transmission component 5, which comprises a manual drive wheel 51 and a manual driven wheel 52. The manual drive wheel 51 and the manual driven wheel 52 are connected in a transmission connection. The manual drive wheel 51 is coaxially connected to the bottom bracket 1 via a first clutch 61, and the manual driven wheel 52 is coaxially connected to the speed regulating ring gear 323. Through the first clutch 61, the rider's power can be transmitted to the manual drive wheel 51 via the bottom bracket 1 and the first clutch 61.

[0069] In this embodiment, the manual drive wheel 51 and the manual driven wheel 52 are directly meshed and connected for transmission. In another embodiment, the manual drive wheel 51 and the manual driven wheel 52 can be connected by a chain, a timing belt, or an idler pulley. For example, when both the manual drive wheel 51 and the manual driven wheel 52 are sprockets, they are connected by a chain; when both the manual drive wheel 51 and the manual driven wheel 52 are pulleys, they are connected by a timing belt; when both the manual drive wheel 51 and the manual driven wheel 52 are gears, they are connected by an idler pulley. Specific designs can be implemented as needed, and will not be elaborated further here.

[0070] In order to transmit the power of the speed regulating planetary gear mechanism 32 to the total output gear 2, the electric speed regulating device also includes a speed regulating transmission component 33. The speed regulating transmission component 33 includes a speed regulating driving gear 331 and a speed regulating driven gear 332. The speed regulating driving gear 331 and the speed regulating driven gear 332 are connected in a driving connection. The speed regulating driving gear 331 is coaxially connected in a driving connection with the speed regulating planetary gear 322, and the speed regulating driven gear 332 is coaxially connected in a driving connection with the total output gear 2.

[0071] This application provides two solutions for the power steering assembly 43. Regarding the solution for the power steering assembly 43... Figure 2 , Figure 4 , Figure 6 , Figure 8 The example shown has the same design for the power steering assembly 43, and is design one. Figure 3 , Figure 5 , Figure 7 , Figure 9 The example shown has the same design for the power steering assembly 43, and is design two.

[0072] like Figure 2 , Figure 4 , Figure 6 , Figure 8 As shown, the power assist transmission assembly 43 includes a first transmission wheel 431 and a second transmission wheel 432. The first transmission wheel 431 and the second transmission wheel 432 are connected in a driving connection. The first transmission wheel 431 is also connected in a driving connection to the power assist drive wheel 42, and the second transmission wheel 432 is connected in a driving connection to the speed regulating gear ring 323. When the power assist motor 41 starts, the power of the power assist motor 41 is transmitted to the first transmission wheel 431 of the power assist transmission assembly 43 through the power assist drive wheel 42. Then, the first transmission wheel 431 transmits the power to the second transmission wheel 432, and finally, the second transmission wheel 432 transmits the power to the speed regulating gear ring 323, thereby realizing the power output. In this case, the first transmission wheel 431 is equivalent to an idler wheel in the transmission path and does not change the output torque of the power assist motor 41.

[0073] like Figure 3 , Figure 5 , Figure 7 , Figure 9As shown, the power assist transmission assembly 43 includes a first transmission wheel 431, a second transmission wheel 432, and a third transmission wheel 433. The first transmission wheel 431 is connected to the power assist drive wheel 42, and the first transmission wheel 431 and the third transmission wheel 433 are coaxially fixedly connected. The first transmission wheel 431 has more teeth than the third transmission wheel 433. The third transmission wheel 433 is connected to the second transmission wheel 432, and the second transmission wheel 432 is connected to the speed regulating gear ring 323. When the power assist motor 41 starts, the power of the power assist motor 41 is transmitted to the first transmission wheel 431 of the power assist transmission assembly 43 through the power assist drive wheel 42, then to the third transmission wheel 433, then to the second transmission wheel 432, and finally to the speed regulating gear ring 323, thereby realizing the power output. In this case, the first transmission wheel 431 and the third transmission wheel 433 can change the output torque of the power assist motor 41, achieving a speed reduction and torque increase assist effect.

[0074] This application provides four clutch engagement schemes, which can be found in [reference 1]. Figures 2 to 9 The clutch scheme shown, wherein, Figure 2 and Figure 3 The first clutch 61 and the second clutch 62 shown are scheme one. Figure 4 and Figure 5 The configuration of the first clutch 61 and the third clutch 63 shown is configuration two. Figure 6 and Figure 7 The scheme shown for the first clutch 61 and the fourth clutch 64 is scheme three. Figure 8 and Figure 9 The scheme shown for the first clutch 61 and the fifth clutch 65 is scheme four.

[0075] like Figure 2 and Figure 3 As shown, the manual drive wheel 51 is connected to the central shaft 1 via the first clutch 61, and the speed-regulating driven wheel 332 is coaxially connected to the central shaft 1 via the second clutch 62. Based on this clutch scheme, the power transmission paths of the power system in assisted mode and unassisted mode are as follows.

[0076] When riding in assist mode, the first clutch 61 is engaged and the second clutch 62 is disengaged. At this time, the rider's riding power is transmitted through the bottom shaft 1 to the human-driven wheel 51, then to the human-driven wheel 52, and then to the speed-regulating ring gear 323. In other words, the rider's riding power participates in riding in assist mode, so that the sensor can accurately obtain the rider's cadence and pedaling force, and obtain a cadence and pedaling force that are more in line with the rider's actual riding state. This makes it easier for the electric assist device to provide electric assistance that is more matched with the pedaling force, and at the same time, it makes it easier for the electric speed regulating device to provide a gear ratio that is more matched with the cadence, thus improving the rider's riding experience.

[0077] When riding in unassisted mode, the second clutch 62 is engaged. At this time, the rider's riding power can be transmitted through the bottom shaft 1 to the speed-adjusting driven wheel 332, then to the main output wheel 2, and finally to the rear wheel 300, thus realizing power transmission in unassisted mode.

[0078] It should be noted that when the first clutch 61 is a friction clutch, in the unassisted mode, the first clutch 61 is in a wedged state, and the speed regulating planetary gear mechanism 32 and the power assist transmission component 43 idle under manual operation. The first clutch 61 can be an electromagnetic powder clutch. In this case, in the unassisted mode, the first clutch 61 can be disengaged by electromagnetic control. At this time, manual operation will not drive the speed regulating planetary gear mechanism 32 and the power assist transmission component 43.

[0079] like Figure 4 and Figure 5 As shown, the manual drive wheel 51 is connected to the central shaft 1 via a first clutch 61. The speed-regulating driven wheel 332 is rotatably mounted on the central shaft 1, and there is no clutch between the speed-regulating driven wheel 332 and the central shaft 1. In this configuration, the power system also includes a housing. The speed-regulating sun gear 321 is rotatably mounted on the housing, and the speed-regulating sun gear 321 is connected to the housing via a third clutch 63. Specifically, the housing has mounting holes to fix the outer ring of the bushing to the housing, and the inner ring of the bushing is fixed to the shaft portion of the speed-regulating sun gear 321. A third clutch 63 is provided between the inner ring of the bushing and the shaft portion of the speed-regulating sun gear 321. The third clutch 63 enables the speed-regulating sun gear 321 to be fixedly connected to the housing or to rotate independently relative to the housing. When the third clutch 63 is engaged, the speed-regulating sun gear 321 is relatively fixed to the housing; when the third clutch 63 is disengaged, the speed-regulating sun gear 321 can rotate relative to the housing. Based on this clutch design, the power transmission paths of the power system in assisted and unassisted modes are as follows.

[0080] In this situation, when riding in assist mode, the first clutch 61 is engaged and the third clutch 63 is disengaged. At this time, the rider's riding power is transmitted through the bottom shaft 1 to the human-driven wheel 51 and the human-driven wheel 52, and then to the speed-regulating ring gear 323. That is, the rider's riding power participates in riding in assist mode, so that the sensor can accurately obtain the rider's cadence and pedaling force, and obtain a cadence and pedaling force that are more in line with the rider's actual riding state. This makes it easier for the electric assist device to provide electric assistance that is more matched with the pedaling force, and at the same time, it makes it easier for the electric speed regulating device to provide a gear ratio that is more matched with the cadence, thus improving the rider's riding experience.

[0081] When riding in power-free mode, the first clutch 61 and the third clutch 63 are engaged. At this time, the rider's power is transmitted through the central shaft 1 to the manual drive wheel 51, and then through the manual driven wheel 52 to the speed-regulating ring gear 323. Since the speed-regulating sun gear 321 is fixed to the housing via the third clutch 63, the rotational speed of the speed-regulating planetary gear 322 is determined. The speed-regulating planetary gear 322 then transmits power to the main output wheel 2 via the speed-regulating drive wheel 331 and the speed-regulating driven wheel 332, and finally to the rear wheel 300, thus achieving power transmission in power-free mode. This design effectively prevents the speed-regulating motor 31 from reversing during power-free riding.

[0082] like Figure 6 and Figure 7 As shown, the manual drive wheel 51 is connected to the central shaft 1 via the first clutch 61, and the speed-regulating driven wheel 332 is coaxially connected to the manual drive wheel 51 via the fourth clutch 64. Based on this clutch scheme, the power transmission paths of the power system in assisted mode and unassisted mode are as follows.

[0083] In the no-assist mode, both the first clutch 61 and the fourth clutch 64 are engaged. The rider's power is transmitted to the human drive wheel 51 through the first clutch 61. The human drive wheel 51 then drives the speed-adjusting driven wheel 332 to rotate synchronously. Finally, the speed-adjusting driven wheel 332 transmits the power to the main output wheel 2, thereby achieving power output in the no-assist mode.

[0084] In power-assisted mode, the first clutch 61 is engaged, the fourth clutch 64 is disengaged, and both the power-assisted motor 41 and the speed-regulating motor 31 are working. Power is transmitted to the speed-regulating driving wheel 331 and the speed-regulating driven wheel 332 via the speed-regulating planetary gear 322, and finally to the total output wheel 2, thereby realizing power output in power-assisted mode.

[0085] Furthermore, when the power system adopts this clutch scheme, the power system also has a fixed speed ratio mode. In the fixed speed ratio mode, the first clutch 61 and the fourth clutch 64 are engaged, the speed-regulating motor 31 is not started, and the assist motor 41 is started. Specifically, when the rider is riding normally, on the one hand, the rider's power is transmitted to the human-driven wheel 51 through the bottom bracket 1, then to the speed-regulating driven wheel 332 through the fourth clutch 64, and finally to the rear wheel 300; on the other hand, the power of the assist motor 41 is transmitted to the speed-regulating gear ring 323 through the assist drive wheel 42 and the assist transmission component 43, then to the human-driven wheel 52 through the speed-regulating gear ring 323, and finally to the human-driven wheel 51 through the human-driven wheel 52 in reverse to assist human riding. That is, this mode is equivalent to the riding mode of an electric-assist bicycle without a continuously variable transmission.

[0086] The fixed speed ratio mode has the following advantages: due to the direct drive of the assist motor 41, the power response is faster than that of the continuously variable transmission (CVT) mode. Ideally, the motor in this scheme can adopt a combination of fixed speed ratio and CVT. In the starting phase, the fixed speed ratio mode is used, that is, the assist motor 41 is directly driven. At this time, the motor's assist response is faster, which can quickly increase the rider's speed. After a certain speed is achieved, the motor enters the CVT mode, driven by the speed-regulating planetary gear mechanism 32, so that the cadence and speed change slowly.

[0087] It should be noted that in the fixed speed ratio mode, for the power transmission at the manual drive wheel 51 and the manual driven wheel 52, the power is transmitted from the manual driven wheel 52 to the manual drive wheel 51, and then to the main output wheel 2 via the fourth clutch 64. This transmission path is different from other modes and from the transmission paths of other examples.

[0088] like Figure 8 and Figure 9 As shown, the manual drive wheel 51 is connected to the central shaft 1 via the first clutch 61, and the planetary gear carrier of the speed-regulating planetary gear 322 is connected to the speed-regulating ring gear 323 via the fifth clutch 65. Based on this clutch scheme, the power transmission path of the power system in assisted mode and unassisted mode is as follows.

[0089] In the no-assist mode, the first clutch 61 and the fifth clutch 65 are engaged. The rider's power is transmitted to the drive wheel 51 through the first clutch 61. The drive wheel 51 then transmits power to the driven wheel 52. The driven wheel 52 transmits power to the speed-regulating ring gear 323. The speed-regulating ring gear 323 drives the speed-regulating planetary gear 322 to rotate through the fifth clutch 65. The speed-regulating planetary gear 322 then drives the speed-regulating drive wheel 331 to rotate synchronously. The speed-regulating drive wheel 331 drives the speed-regulating driven wheel 332 to rotate synchronously. Finally, the speed-regulating driven wheel 332 transmits power to the main output wheel 2, thus achieving power output in the no-assist mode.

[0090] In power-assisted mode, the first clutch 61 is engaged, the fifth clutch 65 is disengaged, and both the power-assisted motor 41 and the speed-regulating motor 31 are working. Power is transmitted to the speed-regulating driving wheel 331 and the speed-regulating driven wheel 332 via the speed-regulating planetary gear 322, and finally to the total output wheel 2, thereby realizing the power output in power-assisted mode.

[0091] Furthermore, when the power system adopts this clutch scheme, the power system has a fixed speed ratio mode. In the fixed speed ratio mode, the first clutch 61 is engaged, the fifth clutch 65 is engaged, the power assist motor 41 is working, and the speed regulating motor 31 is not working. On the one hand, the rider's power is transmitted to the power drive wheel 51, the power driven wheel 52, and the speed regulating gear ring 323 through the first clutch 61; on the other hand, the power of the power assist motor 41 is transmitted to the speed regulating gear ring 323 through the power assist drive wheel 42 and the power assist transmission component 43. Finally, the speed regulating gear ring 323 drives the speed regulating planetary gear 322 to rotate through the fifth clutch 65. Then, the speed regulating planetary gear 322 drives the speed regulating drive wheel 331 and the speed regulating driven wheel 332 to rotate synchronously. Finally, the speed regulating driven wheel 332 transmits the power to the main output wheel 2, thereby realizing the power output in the fixed speed ratio mode.

[0092] The fixed speed ratio mode also has the following advantages: due to the direct drive of the assist motor 41, the power response is faster than that of the continuously variable transmission mode. Ideally, the motor in this scheme can adopt a combination of fixed speed ratio and continuously variable transmission. In the starting stage, the fixed speed ratio mode is used, that is, the assist motor 41 is directly driven. At this time, the motor's assist response is faster, which can quickly increase the rider's speed. After a certain speed is achieved, the motor enters the continuously variable transmission mode, driven by the speed-adjusting planetary gear mechanism 32, so that the cadence and speed change slowly.

[0093] This application also provides an electric-assisted bicycle using the above-described power system, which can have an assisted riding mode, a non-assisted riding mode, and a fixed speed ratio mode. For example, when the electric-assisted bicycle uses... Figures 2 to 5 When the clutch system is used, the electric-assist bicycle has an assisted riding mode and a non-assisted riding mode; when the electric-assist bicycle adopts... Figures 6 to 9 With the clutch design, this electric-assist bicycle features assisted riding mode, unassisted riding mode, and fixed gear ratio mode. The transmission paths for different designs are detailed in the clutch design section and will not be repeated here.

[0094] The foregoing has shown and described the basic principles, main features, and advantages of this application. Those skilled in the art should understand that the above embodiments do not limit this application in any way, and all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of this application.

Claims

1. A power system for an electrically assisted bicycle, characterized in that include: The bottom bracket (1) is used for fixed connection with the crank (400) of the bicycle; The main output wheel (2) is used for drive connection with the rear wheel (300) of the bicycle; The electric speed control device includes a speed control motor (31) and a speed control planetary gear mechanism (32). The speed control planetary gear mechanism (32) includes a speed control sun gear (321), a speed control planetary gear (322), and a speed control ring gear (323). The speed control motor (31) is coaxially connected to the speed control sun gear (321), and the speed control planetary gear (322) is connected to the total output gear (2). The electric power assist device includes a power assist motor (41) and a power assist gear transmission mechanism. The power assist gear transmission mechanism includes a power assist drive wheel (42) and a power assist transmission assembly (43). The power assist motor (41) is coaxially connected to the power assist drive wheel (42), and the output shaft of the power assist transmission assembly (43) is connected to the speed regulating gear ring (323). The speed-regulating motor (31) and the speed-regulating planetary gear mechanism (32) are independently external relative to the central shaft (1); The power assist motor (41) and the power assist gear transmission mechanism are independently external relative to the central shaft (1); The central axis of the power steering wheel (42) is not the same as the central axis of the power steering transmission assembly (43).

2. A power system for an electrically assisted bicycle according to claim 1, characterized in that The power assist transmission assembly (43) includes a first transmission wheel (431) and a second transmission wheel (432). The first transmission wheel (431) is connected to the second transmission wheel (432), the first transmission wheel (431) is connected to the power assist drive wheel (42), and the second transmission wheel (432) is connected to the speed regulating gear ring (323).

3. A power system for an electrically assisted bicycle according to claim 1, characterized in that, The power assist transmission assembly (43) includes a first transmission wheel (431), a second transmission wheel (432), and a third transmission wheel (433). The first transmission wheel (431) is connected to the power assist drive wheel (42). The first transmission wheel (431) and the third transmission wheel (433) are coaxially fixedly connected. The first transmission wheel (431) has more teeth than the third transmission wheel (433). The third transmission wheel (433) is connected to the second transmission wheel (432). The second transmission wheel (432) is connected to the speed regulating gear ring (323).

4. Power system for electrically assisted bicycles according to any of claims 1-3, characterized in that, It also includes a human-powered transmission assembly (5), which includes a human-powered drive wheel (51) and a human-powered driven wheel (52). The human-powered drive wheel (51) and the human-powered driven wheel (52) are connected in a transmission connection. The human-powered drive wheel (51) is coaxially connected to the central shaft (1) through a first clutch (61), and the human-powered driven wheel (52) is coaxially connected to the speed regulating gear ring (323).

5. A power system for an electrically assisted bicycle according to claim 4, characterized in that The electric speed control device further includes a speed control transmission assembly (33), which includes a speed control drive wheel (331) and a speed control driven wheel (332). The speed control drive wheel (331) is connected to the speed control driven wheel (332) in a transmission connection. The speed control drive wheel (331) is connected to the speed control planetary gear (322) in a transmission connection. The speed control driven wheel (332) is connected to the total output wheel (2) in a transmission connection.

6. A power system for an electrically assisted bicycle according to claim 5, characterized in that The speed-regulating driven wheel (332) is coaxially connected to the central shaft (1) via the second clutch (62).

7. A power system for an electrically assisted bicycle according to claim 5, characterized in that The speed-regulating driven wheel (332) is rotatably connected to the central shaft (1). The power system for the electric-assisted bicycle also includes a housing. The speed-regulating sun gear (321) is rotatably mounted on the housing, and a third clutch (63) is provided between the speed-regulating sun gear (321) and the housing. When the third clutch (63) is engaged, the speed-regulating sun gear (321) is relatively fixed to the housing. When the third clutch (63) is disengaged, the speed-regulating sun gear (321) can rotate relative to the housing.

8. A power system for an electrically assisted bicycle according to claim 5, characterized in that, The speed-regulating driven wheel (332) and the human-powered driving wheel (51) are coaxially connected via a fourth clutch (64).

9. A power system for an electrically assisted bicycle according to claim 5, characterized in that, The planetary carrier of the speed-regulating planetary gear (322) is connected to the speed-regulating ring gear (323) via a fifth clutch (65).

10. An electrically assisted bicycle, characterised in that It includes a frame (100) and a power system for an electric-assisted bicycle as described in any one of claims 1-9, the power system for the electric-assisted bicycle being mounted on the frame (100).

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