Electric power-assisted speed control system and bicycle

Abstract

The utility model relates to the technical field of electric power-assisted speed control systems of bicycles, and discloses an electric power-assisted speed control system and a bicycle. A shell of the electric power-assisted speed control system is provided with a rotatable first power shaft and a transmission shaft; a rotor of the motor set is connected with the driving gear, the first planetary gear set and the second planetary gear set share the same inner gear ring, and a first sun gear is arranged on the first planet carrier. The first planet gear is meshed with the inner gear ring and the driving gear; a first clutch transmission assembly is arranged between the first power shaft and the first sun gear; a plurality of second planet gears are fixedly connected with the multi-stage driving gear set and are meshed with the inner gear ring and the first sun gear; a second clutch transmission assembly is arranged between the transmission shaft and each stage of the multi-stage driven wheel set. A gear shifting convex part of the first gear shifting mechanism is propped against the first clutch transmission assembly, so that the first power shaft is in transmission connection with the first sun gear; and the gear shifting convex part of the second gear shifting mechanism is propped against any second clutch transmission component, so that the corresponding driven wheel is in transmission connection with the transmission shaft.

Description

TECHNICAL FIELD

[0001] The utility model relates to the electric power assist variable speed system technical field of bicycle, especially electric power assist variable speed system. BACKGROUND

[0002] The main electric power assist bicycle motor of market at present is ordinary deceleration middle -position motor, cannot realize the change gear to change speed, and bicycle speed change still needs to rely on its own external speed change mechanism to realize speed change.

[0003] The Chinese utility model patent of patent application number CN202110458425.7 discloses that the power assisting drive mechanism and the speed change mechanism, the change gear drive mechanism superposition realize can with the automatic control of motor matching, realize centralized control.But because it is just simple function superposition causes volume too big, speed change mechanism is complex, and practicality is not big.

[0004] With the popularity of electric power assist bicycle, the field urgently needs a highly integrated, small volume and high efficiency, and centralized control of middle-position electric power assist hybrid transmission. UTILITY MODEL CONTENTS

[0005] Therefore, the utility model provides an electric power assist variable speed system to solve the technical problems in the above background art.

[0006] To achieve one or part or all of the above purposes or other purposes, the utility model provides an electric power assist variable speed system, comprising: a housing, a first power shaft that is at least partially hollow, a first gear shifting mechanism, a transmission shaft that is at least partially hollow, a second gear shifting mechanism, an electric power assist module, a second planetary gear set, a multi-stage driving wheel set, and a multi-stage driven wheel set.

[0007] The first power shaft and the transmission shaft are both rotatably connected to the housing, and the first power shaft has a first power input end that extends out of the housing at both ends, and the transmission shaft has a power output end that extends out of the housing at one end.

[0008] The electric power assist module includes a motor set and a first planetary gear set, and the first planetary gear set includes a driving gear, a first planet carrier, and a plurality of first planet wheels rotatably arranged on the first planet carrier.

[0009] The stator of the motor set is fixed to the housing, and the rotor of the motor set is hollow along the axial direction, and the rotor is connected to the driving gear in the axial direction, and the rotor is coaxially distributed with the first power shaft, and there is a gap between the rotor and the first power shaft.

[0010] The first planetary gear set and the second planetary gear set share the same inner ring gear, and the inner ring gear is fixed to the housing.

[0011] The first planet carrier is rotatably arranged on the first power shaft, and the first planet carrier is axially provided with a first sun gear; a plurality of first planet gears are rotatably arranged on the first planet carrier, and the first planet gears are in meshing connection with the inner ring gear and the drive gear;

[0012] The first power shaft and the first sun gear are provided with a first clutch transmission assembly therebetween;

[0013] The second planetary gear set has a plurality of second planet gears, the plurality of second planet gears are fixedly connected with the multi-stage driving gear set, and the second planet gears are in meshing connection with the inner ring gear and the first sun gear; the multi-stage driving gear set is rotatably arranged on the first power shaft;

[0014] The multi-stage driven gear set is rotatably arranged on the transmission shaft, and the transmission shaft and each stage of the multi-stage driven gear set are provided with a second clutch transmission assembly therebetween;

[0015] The first shift mechanism has a movable first limiting shaft extending into the interior of the first power shaft, and the second shift mechanism has a movable second limiting shaft extending into the interior of the transmission shaft; the first limiting shaft and the second limiting shaft both have a shift protrusion;

[0016] The first shift mechanism can drive the first limiting shaft to make the shift protrusion of the first limiting shaft abut against the first clutch transmission assembly, so that the first power shaft and the first sun gear are in transmission connection; the second shift mechanism can drive the second limiting shaft to make the shift protrusion of the second limiting shaft abut against any one of the second clutch transmission assemblies, so that the corresponding driven gear and the transmission shaft are in transmission connection.

[0017] Preferably, the multi-stage driving gear set comprises a first driving gear, a second driving gear, a third driving gear and a plurality of limiting rods; the multi-stage driven gear set comprises a first driven gear, a second driven gear and a third driven gear;

[0018] The first driving gear is axially provided with a connecting portion;

[0019] The second driving gear is sleeved on the connecting portion and is fixedly connected with the first driving gear coaxially;

[0020] A plurality of limiting rods are arranged corresponding to the plurality of second planet gears, one end of the limiting rod passes through the second planet gear, the third driving gear in sequence and is fixedly connected with the first driving gear; the first power shaft and the third driving gear are provided with a third clutch transmission assembly therebetween;

[0021] The first shift mechanism can drive the first limiting shaft to make the shift protrusion of the first limiting shaft abut against the third clutch transmission assembly, so that the first power shaft and the third driving gear are in transmission connection;

[0022] The first driving wheel and the first driven wheel are engaged, the second driving wheel and the second driven wheel are engaged, and the third driving wheel and the third driven wheel are engaged.

[0023] Preferably, the multi-stage driving wheel set comprises a third planetary gear set, the third planetary gear set comprising a second carrier, a second sun gear and a plurality of third planetary gears; an inner wall of the first driving wheel is provided with an inner tooth portion;

[0024] The second sun gear is fixed on the housing;

[0025] The second carrier is rotatably arranged on the first power shaft, the plurality of third planetary gears are arranged on the second carrier, and the third planetary gears engage the second sun gear and the inner tooth portion;

[0026] A fourth clutch transmission assembly is arranged between the first power shaft and the second carrier;

[0027] The first shift mechanism can drive the first limiting shaft to make the shift protrusion of the first limiting shaft abut against the fourth clutch transmission assembly, so that the first power shaft and the second carrier are in transmission connection.

[0028] Preferably, the first power shaft and the transmission shaft are both provided with mounting holes; the first clutch transmission assembly, the third clutch transmission assembly and the fourth clutch transmission assembly are all formed by a first pawl and a first ratchet structure, the first pawl is connected with an elastic sheet, and the first pawl is assembled into the mounting hole through the elastic sheet; the first ratchet structure is arranged on the first sun gear, the third driving wheel and the second carrier; when the first pawl is not abutted by the shift protrusion, the first pawl is compressed by the elastic sheet and is in a retracted state and is not connected with the corresponding first ratchet structure; when the first pawl is abutted by the shift protrusion, the first pawl is in an extended state and can be in transmission connection with the corresponding first ratchet structure, and an avoidance space is formed between the first pawl and the mounting hole;

[0029] The second clutch transmission assembly is formed by a second pawl and a second ratchet structure, the second pawl is connected with an elastic sheet, and the second pawl is assembled into the mounting hole through the elastic sheet; the second ratchet structure is arranged on each stage of the multi-stage driven wheel set; when the second pawl is not abutted by the shift protrusion, the second pawl is compressed by the elastic sheet and is in a retracted state and is not connected with the corresponding second ratchet structure; when the second pawl is abutted by the shift protrusion, the second pawl is in an extended state and can be in transmission connection with the corresponding second ratchet structure, and there is no avoidance space between the outer wall of the second pawl and the inner wall of the mounting hole.

[0030] Preferably, the first shift mechanism and the second shift mechanism both comprise a control module and a control motor;

[0031] The first power shaft and the transmission shaft are both provided with an axially extending threaded hole in the interior thereof;

[0032] The outer wall of the first limiting shaft and the second limiting shaft is provided with external threads which are threadedly connected with the threaded holes;

[0033] The first limiting shaft and the second limiting shaft are internally provided with a connecting hole which penetrates in the axial direction and is connected with the rotating shaft of the control motor, and the screw rod can move along the axial direction of the rotating shaft of the control motor;

[0034] The control module is electrically connected with the control motor.

[0035] Preferably, the first pawl and the second pawl are both provided with a groove which is connected with the elastic sheet, and the first pawl and the second pawl are provided with a transition inclined wall which can be abutted by the axial movement of the shift protrusion.

[0036] Preferably, the connecting part is an axial protrusion which is connected with the first driving wheel, and the outer wall of the axial protrusion and the inner wall of the second driving wheel are provided with interfitting splines.

[0037] Preferably, the shell comprises a left cover, a right cover and a middle shell which is open at both ends;

[0038] One end of the first power shaft passes through the left cover and is connected with the left cover through a bearing, and the other end passes through the right cover and is connected with the right cover through a bearing; one end of the transmission shaft is connected with the left cover through a bearing, and the other end passes through the right cover and is connected with the right cover through a bearing; wherein the stator of the motor group is fixed on the left cover;

[0039] The left cover and the middle shell are sealingly connected at one end opening, and the right cover and the middle shell are sealingly connected at the other end opening.

[0040] Preferably, it further comprises a first reversing gear set, the first reversing gear set comprises a plurality of reversing planetary gears, a transmission frame and an output cylinder;

[0041] The transmission frame is provided with an axially misaligned inner tooth ring and a connecting ring, and the transmission frame is fixed on the transmission shaft through the connecting ring;

[0042] The plurality of reversing planetary gears are mounted on the shell, and the reversing planetary gears are engaged with the inner tooth ring;

[0043] The output cylinder is rotatably mounted on the transmission shaft, and one end of the output cylinder is provided with an external tooth part for engaging with the reversing planetary gears, and the other end of the output cylinder passes through the shell and is provided with a second power output end.

[0044] An electrically assisted variable speed system, comprising: a shell, a first power shaft which is at least partially hollow, a first gear shifting mechanism, a transmission shaft which is at least partially hollow, a second gear shifting mechanism, an electrically assisted power module, a second planetary gear set, a plurality of stages of driving wheels, a plurality of stages of driven wheels and a second reversing gear set;

[0045] The first power shaft and the transmission shaft are rotatably connected to the housing, and the first power shaft has a first power input end which extends out of the housing at both ends;

[0046] The second reversing gear set comprises a transmission gear and an output gear, the transmission gear is coaxially fixed on the transmission shaft, and the output gear is rotatably installed on the first power shaft and engaged with the transmission gear; the output gear is provided with an axially extending third power output end which extends out of the housing;

[0047] The electric power assisting module comprises a motor set and a first planetary gear set; the first planetary gear set comprises a driving gear, a first planet carrier and a plurality of first planet gears rotatably arranged on the first planet carrier;

[0048] The stator of the motor set is fixed on the housing, and the rotor of the motor set is hollowly arranged in the axial direction, the rotor is axially connected to the driving gear, the rotor is coaxially distributed with the first power shaft, and there is a spacing between the rotor and the first power shaft;

[0049] The first planetary gear set and the second planetary gear set share the same inner ring gear, and the inner ring gear is fixed on the housing;

[0050] The first planet carrier is rotatably arranged on the first power shaft, and the first planet carrier is axially provided with a first sun gear; a plurality of first planet gears are rotatably installed on the first planet carrier, and the first planet gears are engaged with the inner ring gear and the driving gear;

[0051] The first power shaft and the first sun gear are provided with a first clutch transmission assembly therebetween;

[0052] The second planetary gear set has a plurality of second planet gears, the plurality of second planet gears are fixedly connected with the plurality of primary driving gears, and the second planet gears are engaged with the inner ring gear and the first sun gear; the plurality of primary driving gears are rotatably arranged on the first power shaft;

[0053] The plurality of secondary driving gears are rotatably arranged on the transmission shaft, and the transmission shaft and each level of the plurality of secondary driving gears are provided with a second clutch transmission assembly therebetween;

[0054] The first shift mechanism has a movable first limiting shaft which extends into the first power shaft, and the second shift mechanism has a movable second limiting shaft which extends into the transmission shaft; the first limiting shaft and the second limiting shaft both have a shift protrusion;

[0055] The first shift mechanism can drive the first limiting shaft to make the shift protrusion of the first limiting shaft abut against the first clutch transmission assembly, so that the first power shaft and the first sun gear are in transmission connection; the second shift mechanism can drive the second limiting shaft to make the shift protrusion of the second limiting shaft abut against any one of the second clutch transmission assemblies, so that the corresponding driven gear and the transmission shaft are in transmission connection.

[0056] An electrically assisted variable speed system, comprising: a housing, a support shaft which is at least partially hollow, a first shift mechanism, a transmission shaft which is at least partially hollow, a second shift mechanism, an electrically assisted module, a second planetary gear set, a multi-stage driving gear set, a multi-stage driven gear set, and a second power shaft;

[0057] The second power shaft, the support shaft, and the transmission shaft are all rotatably connected to the housing, and the transmission shaft has a power output end extending out of the housing; the second power shaft has a second power input end extending out of the housing at both ends, and the second power shaft is provided with an input gear;

[0058] The electrically assisted module comprises a motor set and a first planetary gear set; the first planetary gear set comprises a driving gear, a first carrier, and a plurality of first planet gears rotatably arranged on the first carrier;

[0059] The stator of the motor set is fixed on the housing, and the rotor of the motor set is arranged in an axial hollow manner; the rotor is axially connected to the driving gear, and the rotor and the support shaft are coaxially distributed with a spacing therebetween;

[0060] The first planetary gear set and the second planetary gear set share the same inner ring gear, and the inner ring gear is fixed on the housing;

[0061] The first carrier is rotatably arranged on the support shaft, and the first carrier is axially provided with a first sun gear; the plurality of first planet gears are rotatably mounted on the first carrier, and the first planet gears mesh with the inner ring gear and the driving gear;

[0062] The first clutch transmission assembly is arranged between the support shaft and the first sun gear;

[0063] The second planetary gear set has a plurality of second planet gears, the plurality of second planet gears are fixedly connected to the multi-stage driving gear set, and the second planet gears mesh with the inner ring gear and the first sun gear; the multi-stage driving gear set is rotatably arranged on the support shaft, and any stage of the multi-stage driving gear set can mesh with the input gear;

[0064] The multi-stage driven gear set is rotatably arranged on the transmission shaft, and the transmission shaft and each stage of the multi-stage driven gear set are both provided with a second clutch transmission assembly;

[0065] The first gear shifting mechanism has a movable first limiting shaft extending into the support shaft, and the second gear shifting mechanism has a movable second limiting shaft extending into the transmission shaft; the first limiting shaft and the second limiting shaft each have a gear shifting protrusion;

[0066] The first gear shifting mechanism can drive the first limiting shaft to make the gear shifting protrusion abut against the first clutch transmission assembly, so that the support shaft and the first sun gear are in transmission connection; the second gear shifting mechanism can drive the second limiting shaft to make the gear shifting protrusion abut against any one of the second clutch transmission assemblies, so that the corresponding driven gear and the transmission shaft are in transmission connection.

[0067] A bicycle comprising the electric power-assisted gear shifting system.

[0068] The embodiments of the present application have the following beneficial effects:

[0069] After the above scheme is adopted, the motor set coaxially distributed with the first power shaft is arranged in the shell, the rotor of the motor provides power for the first planetary gear, and the power is transmitted by the first planetary carrier and the first sun gear, the multi-stage driving gear set is driven to rotate by the second planetary gear and provides power for the multi-stage driven gear set for output; the first gear shifting mechanism can make the first sun gear and the first power shaft in transmission connection, at this time, the two first power input ends of the first power shaft provide power, the power is enlarged by the plurality of second planetary gears and directly drives the multi-stage driving gear set to rotate, and provides power for the multi-stage driven gear set for output; it can be seen that the motor set provides the power source of built-in electric power driving for the multi-stage driving gear set, the first gear shifting mechanism and the first clutch transmission assembly can make the first sun gear and the first power shaft in transmission connection, so that the first power input end of the first power shaft provides another power source for the multi-stage driving gear set, and the two power sources are independent of each other and do not interfere with each other, so that the user can select the corresponding power source according to the actual situation when using the bicycle with the electric power-assisted gear shifting system, and the riding experience of the user is effectively improved; in addition, since the transmission shaft is in transmission connection with each level of the multi-stage driven gear set, a plurality of different output speeds can be obtained, and the entire system can provide a plurality of different gear shifts according to the number of gears of the multi-stage driven gear set. BRIEF DESCRIPTION OF DRAWINGS

[0070] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description, and obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating any creative labor.

[0071] Among them:

[0072] Figure 1Overall structure schematic diagram of embodiment one;

[0073] Figure 2 Overall structure exploded view of embodiment one;

[0074] Figure 3 Overall structure cross-sectional view of embodiment one;

[0075] Figure 4 Structure schematic diagram of embodiment one without shell;

[0076] Figure 5 Structure exploded view of embodiment one without shell;

[0077] Figure 6 First power shaft partial structure separation schematic diagram of embodiment one;

[0078] Figure 7 Transmission shaft partial structure schematic diagram of embodiment one;

[0079] Figure 8 A-A cross-sectional view of Figure 3 ;

[0080] Figure 9 B-B cross-sectional view of Figure 3 ;

[0081] Figure 10 C-C cross-sectional view of Figure 3 ;

[0082] Figure 11 D-D cross-sectional view of Figure 3 ;

[0083] Figure 12 Structure schematic diagram of first power shaft and first shift mechanism of embodiment one;

[0084] Figure 13 Structure schematic diagram of first driving wheel of embodiment one;

[0085] Figure 14 Schematic diagram of first pawl and first power shaft, second pawl and transmission shaft in embodiment one;

[0086] Figure 15 Cross-sectional view of first pawl and second pawl in embodiment one when assembled;

[0087] Figure 16 Structure schematic diagram of second pawl and spring in embodiment one;

[0088] Figure 17 Structure schematic diagram of first reversing gear set in embodiment two Figure 1 ;

[0089] Figure 18 Structure diagram of the first reversing gear set in Example Two Figure 2 ;

[0090] Figure 19 Structure diagram of the second reversing gear set in Example Three

[0091] Figure 20 Internal structure diagram of the second reversing gear set in Example Three

[0092] Figure 21 Structure separation diagram of the second reversing gear set in Example Three

[0093] Figure 22 Internal structure diagram in Example Four

[0094] Reference signs:

[0095] 1, housing; 101, right cover; 102, left cover; 103, middle shell

[0096] 20, first power shaft; 200, mounting hole; 201, first power input end; 202, threaded hole; 21, transmission shaft; 211, first power output end; 212, transmission spline; 22, first reversing gear set; 220, reversing planetary gear; 221, transmission carrier; 221a, inner tooth ring; 221b, connecting ring; 222, output cylinder; 222a, outer tooth part; 222b, second power output end; 23, second reversing gear set; 230, output gear; 230a, third power output end; 231, transmission gear; 24, second power shaft; 240, input gear; 241, second power input end; 25, support shaft

[0097] 30, first gear shifting mechanism; 301, first limit shaft; 301a, gear shifting convex part; 301b, connecting hole; 302, control module; 302a, control board; 302b, battery; 302c, protective shell; 303, control motor; 31, second gear shifting mechanism; 311, second limit shaft

[0098] 4, motor set; 40, stator; 41, rotor; 42, drive gear

[0099] 5, first planetary gear set; 50, inner tooth ring; 51, first planetary carrier; 52, first planetary gear; 53, first sun gear

[0100] 6, second planetary gear set; 60, second planetary gear

[0101] 7, multi-stage driving wheel set; 70, third planetary gear set; 702, second planet carrier; 703, third planet wheel; 704, second sun wheel; 71, first driving wheel; 710, connecting part; 711, inner tooth part; 72, second driving wheel; 73, third driving wheel; 74, limiting rod;

[0102] 8, multi-stage driven wheel set; 81, first driven wheel; 82, second driven wheel; 83, third driven wheel;

[0103] 90, first pawl; 91, first ratchet structure; 92, second pawl; 920, groove; 921, transition inclined wall; 93, second ratchet structure; 94, elastic sheet. DETAILED DESCRIPTION

[0104] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the specification herein is for describing particular embodiments only and is not intended to be limiting of the application; the present application is well suited to carry out the objects and advantages thereof and will be understood by practitioners of the art. The following detailed description is presented primarily for the purpose of enabling others to make and use the application.

[0105] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase "in an embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily all directed to the same embodiment, or to a single alternative embodiment. It is explicitly contemplated that embodiments described herein can be combined with each other.

[0106] For those skilled in the art to better understand the technical scheme of the present application, the technical scheme in the embodiments of the present application will be described clearly and completely in conjunction with the drawings.

[0107] Embodiment one:

[0108] As shown in the accompanying drawings, Figures 1-16 The electric power-assisted transmission system provided by the embodiments of the present application comprises: a housing 1, a first power shaft 20 which is at least partially hollow, a first gear shifting mechanism 30, a transmission shaft 21 which is at least partially hollow, a second gear shifting mechanism 31, an electric power-assisted module, a second planetary gear set 6, a multi-stage driving wheel set 7, and a multi-stage driven wheel set 8.

[0109] The first power shaft 20 and the transmission shaft 21 are both rotatably connected to the shell 1, and the first power shaft 20 has a first power input end 201 extending out of the shell 1 at both ends, and the transmission shaft 21 has a first power output end 211 extending out of the shell 1 at one end;

[0110] The electric power assisting module comprises a motor set 4 and a first planetary gear set 5, the first planetary gear set 5 comprising a driving gear 42, a first planet carrier 51 and a plurality of first planet gears 52 rotatably arranged on the first planet carrier 51;

[0111] The stator 40 of the motor set 4 is fixed on the shell 1, and the rotor 41 of the motor set 4 is arranged in an axial hollow manner, the rotor 41 is connected to the driving gear 42 in an axial direction, the rotor 41 is coaxially distributed with the first power shaft 20, and there is a spacing between the rotor 41 and the first power shaft 20;

[0112] The first planetary gear set 5 and the second planetary gear set 6 share the same inner ring gear 50, and the inner ring gear 50 is fixed on the shell 1;

[0113] The first planet carrier 51 is rotatably arranged on the first power shaft 20, and the first planet carrier 51 is provided with a first sun gear 53 in an axial direction; a plurality of first planet gears 52 are rotatably mounted on the first planet carrier 51, and the first planet gears 52 mesh with the inner ring gear 50 and the driving gear 42;

[0114] A first clutch transmission assembly is arranged between the first power shaft 20 and the first sun gear 53;

[0115] The second planetary gear set 6 has a plurality of second planet gears 60, the plurality of second planet gears 60 are fixedly connected with the plurality of primary driving gear sets 7, and the second planet gears 60 mesh with the inner ring gear 50 and the first sun gear 53; the plurality of primary driving gear sets 7 are rotatably arranged on the first power shaft 20;

[0116] The plurality of secondary driven gear sets 8 are rotatably arranged on the transmission shaft 21, and a second clutch transmission assembly is arranged between the transmission shaft 21 and each of the plurality of secondary driven gear sets 8;

[0117] The first shift mechanism 30 has a movable first limiting shaft 301 extending into the interior of the first power shaft 20, and the second shift mechanism 31 has a movable second limiting shaft 311 extending into the interior of the transmission shaft 21; the first limiting shaft 301 and the second limiting shaft 311 both have a shift protrusion 301a;

[0118] The first shift mechanism 30 can drive the first limiting shaft 301 to make the shift protrusion 301a of the first limiting shaft 301 abut against the first clutch transmission assembly, so that the first power shaft 20 and the first sun gear 53 are in transmission connection; the second shift mechanism 31 can drive the second limiting shaft 311 to make the shift protrusion 301a of the second limiting shaft 311 abut against any second clutch transmission assembly, so that the corresponding driven gear and the transmission shaft 21 are in transmission connection.

[0119] In the present embodiment, the first power shaft 20 has two first power input ends 201, both of which extend out of the housing 1, and are used to connect the bicycle cranks and pedals, and the transmission shaft 21 has a first power output end 211, which extends out of the housing 1, and is used to connect the bicycle sprocket, which is further transmitted to the wheel through the chain or the like. The above-mentioned multi-stage driving wheel set 7 and the multi-stage driven wheel set 8 can be a combination of a plurality of gears of different sizes or specifications, for example, the multi-stage driving wheel set 7 is a combination of three gears of different sizes, and the multi-stage driven wheel set 8 is a combination of three gears of different sizes, each of which corresponds to a stage, such as Figure 4 and Figure 5The gears shown can also be a combination of four, five or six gears, or even more, or a combination of two gears, as long as the driving gears of each stage and the driven gears of each stage correspond to each other after installation. The rotor 41 of the motor set 4 in this embodiment is hollow in the axial direction to facilitate the passage of the first power shaft 20, and the internal space of the housing 1 is used reasonably to ensure that the rotor 41 and the first power shaft 20 rotate independently of each other. Specifically, a bearing can be installed between the inner wall of the rotor 41 and the first power shaft 20 to improve the stability of the connection. The driving gear 42 on the rotor 41 of the battery 302b gear set is engaged with the first planetary gear 52, i.e. the driving gear 42 acts as the sun gear of the first planetary gear set 5. The power is input through the driving gear 42 and then amplified through the plurality of first planetary gears 52 and output to the second planetary gear set 6. The second planetary gear set 6 is fixedly connected with the multi-stage driving gear set 7 to form a whole, and the power is finally output to the multi-stage driven gear set 8 through the multi-stage driving gear set 7. When the motor set 4 is selected as the power source, the first shift mechanism 30 makes the shift protrusion 301a not connected with the first clutch transmission assembly, i.e. the first sun gear 53 idles on the first power shaft 20, to avoid the first power shaft 20 rotating and causing the pedal connected to the first power input end 201 to rotate when the motor set 4 drives the multi-stage driving gear set 7 to rotate. Specifically, a control circuit board for controlling the motor 303 gear set and a corresponding power supply can be provided in the housing 1. The control circuit board is provided with wireless receiving modules such as Bluetooth and WiFi to facilitate user control and selection of the corresponding power source and the speed of the rotor 41 when the motor set 4 is selected as the power source. Correspondingly, when the first power input end 201 at both ends of the first power shaft 20 is selected as the power source, the shift protrusion 301a of the first limiting shaft 301 is controlled by the first shift mechanism 30 to abut against the first clutch transmission assembly, so that the first power shaft 20 is in transmission connection with the first sun gear 53. At this time, the power is input through the first power input end 201 of the first power shaft 20, amplified through the first sun gear 53 and the plurality of second planetary gears 60, and then output to the multi-stage driving gear set 7, and finally output through the multi-stage driven gear set 8 and the first power output end 211 of the transmission shaft 21.

[0120] The multi-stage driven gear set 8 can be rotatably arranged on the transmission shaft 21, and each gear on the multi-stage driven gear set 8 rotates independently of each other. The first clutch transmission assembly and the second clutch transmission assembly are both assemblies that can separate or engage the transmission, which can be a ratchet 90 structure as described later, or other forms, for example, two friction plates, which are controlled by the shift protrusion 301a to control the transmission separation or engagement.

[0121] Referring to the drawings Figure 8 and the drawings Figure 9, when the first shift mechanism 30 drives the first limiting shaft 301 to make its shift convex 301a abut the first clutch transmission assembly, so that the first power shaft 20 and the first sun gear 53 are transmission connected, at this time, the rotor 41 of the motor set 4 is in an idling state, the power is transmitted into the first power input end 201 of the first power shaft 20, and then is enlarged by the plurality of second planetary gears 60 of the second planetary gear set 6, and directly drives the plurality of primary gear sets 7 to rotate, the second shift mechanism 31 drives the second limiting shaft 311 to make its shift convex 301a abut the second clutch transmission assembly required to be output, so that the corresponding driven gear and the transmission shaft 21 are transmission connected, for example, the shift convex 301a of the second limiting shaft 311 abuts the first gear on the left of the plurality of driven gear sets 8, at this time, the power is transmitted from the first gear on the left of the plurality of primary gear sets 7 to the first gear on the left of the plurality of driven gear sets 8, and then is transmitted to the transmission shaft 21, and finally drives the toothed disc connected to the first power output end 211 on the transmission shaft 21 to output. Although the plurality of primary gear sets 7 and the plurality of driven gear sets 8 are all engaged in the above transmission process, only the first gear on the left of the plurality of driven gear sets 8 has a transmission relationship with the transmission shaft 21, and the other gears of the plurality of driven gear sets 8 are idling, which does not affect the transmission process. If the first shift mechanism 30 drives the first limiting shaft 301 to make its shift convex 301a not abut the first clutch transmission assembly, so that the first sun gear 53 is not transmission connected with the first power shaft 20 and is in an idling state; at this time, the motor set 4 is started and power is provided by the rotor 41, the power is transmitted into the driving gear 42, drives the plurality of first planetary gears 52 to rotate, and then is transmitted to the plurality of second planetary gears 60 through the first planetary carrier 51 and the second sun gear 704, drives the plurality of primary gear sets 7 to rotate, the second shift mechanism 31 drives the second limiting shaft 311 to make its shift convex 301a abut the second clutch transmission assembly required to be output, so that the corresponding driven gear and the transmission shaft 21 are transmission connected, for example, the shift convex 301a of the second limiting shaft 311 abuts the first gear on the left of the plurality of driven gear sets 8, at this time, the power is transmitted from the first gear on the left of the plurality of primary gear sets 7 to the first gear on the left of the plurality of driven gear sets 8, and then is transmitted to the transmission shaft 21, and finally drives the toothed disc connected to the first power output end 211 on the transmission shaft 21 to output. Although the plurality of primary gear sets 7 and the plurality of driven gear sets 8 are all engaged in the above transmission process, only the first gear on the left of the plurality of driven gear sets 8 has a transmission relationship with the transmission shaft 21, and the other gears of the plurality of driven gear sets 8 are idling, which does not affect the transmission process.

[0122] In summary, the motor set 4 is arranged coaxially with the first power shaft 20 in the shell 1, the rotor 41 of the motor provides power for the first planetary gear 52, and the power is transmitted by the first planet carrier 51 and the first sun gear 53, the second planetary gear 60 drives the multi-stage driving wheel set 7 to rotate and provides power for the multi-stage driven wheel set 8 to output; the first shift mechanism 30 can make the first sun gear 53 and the first power shaft 20 in transmission connection, at this time, the two first power input ends 201 of the first power shaft 20 provide power, the power is enlarged by the plurality of second planetary gears 60 and directly drives the multi-stage driving wheel set 7 to rotate, and provides power for the multi-stage driven wheel set to output; it can be seen that the motor set 4 provides the power source for the multi-stage driving wheel set 7, the first shift mechanism 30 and the first clutch transmission assembly can make the first sun gear 53 and the first power shaft 20 in transmission connection, so that the first power input end 201 of the first power shaft 20 provides another power source for the multi-stage driving wheel set 7, and the two power sources are independent of each other and do not interfere with each other, so that the user can select the corresponding power source according to the actual situation when using the bicycle with the electric power-assisted variable speed system, effectively improving the riding experience of the user; in addition, since the transmission shaft 21 is in transmission connection with each level of the multi-stage driven wheel set 8, a plurality of different output speeds can be obtained, and the whole system can provide a plurality of different variable speeds according to the number of gears of the multi-stage driven wheel set 8.

[0123] Referring to the drawings Figure 4 and the drawings Figure 5 The multi-stage driving wheel set 7 includes a first driving wheel 71, a second driving wheel 72, a third driving wheel 73 and a plurality of limiting rods 74; the multi-stage driven wheel set 8 includes a first driven wheel 81, a second driven wheel 82 and a third driven wheel 83;

[0124] The first driving wheel 71 is provided with a connecting portion in the axial direction;

[0125] The second driving wheel 72 is coaxially fixed on the connecting portion of the first driving wheel 71;

[0126] A plurality of limiting rods 74 are arranged corresponding to the plurality of second planetary gears 60, one end of the limiting rod 74 passes through the second planetary gear 60, the third driving wheel 73 in sequence and is fixedly connected with the first driving wheel 71; the third clutch transmission assembly is arranged between the first power shaft 20 and the third driving wheel 73;

[0127] The first shift mechanism 30 can drive the first limiting shaft 301 to make the shifting protrusion 301a abut against the third clutch transmission assembly to make the first power shaft 20 and the third driving wheel 73 in transmission connection;

[0128] The first driving wheel 71 and the first driven wheel 81 are engaged, the second driving wheel 72 and the second driven wheel 82 are engaged, and the third driving wheel 73 and the third driven wheel 83 are engaged.

[0129] Specifically, the connecting portion is arranged axially on the first driving wheel 71, and can specifically be an axial protrusion on the first driving wheel 71, and the outer wall of the axial protrusion is provided with a spline, and the inner wall of the second driving wheel 72 has an inner spline that is fitted with the spline of the axial protrusion, the second driving wheel 72 is sleeved on the connecting portion and rotates with the first driving wheel 71 to have the same angular velocity; while the third driving wheel 73 is connected to the second planetary gear 60 and the first driving wheel 71 through the limiting rod 74, and specifically, a threaded through hole can be arranged on the inner wall of the connecting portion of the first driving wheel 71, so that the limiting rod 74 is threadedly connected with the first driving wheel 71 after passing through the second planetary gear 60 and the third driving wheel 73, so that the third driving wheel 73 has the same angular velocity as the first driving wheel 71, and it is ensured that the rotation of the plurality of second planetary gears 60 drives the third driving wheel 73, the second driving wheel 72 and the first driving wheel 71 to rotate together; in order to increase the number of gear positions of the electric power-assisted transmission system, a third clutch transmission assembly is arranged between the third driving wheel 73 and the first power shaft 20, when the first shift mechanism 30 drives the first limiting shaft 301 to make the shift protrusion 301a abut against the third clutch transmission assembly, the first power shaft 20 is in transmission connection with the third driving wheel 73, power is transmitted into through the first power input end 201 of the first power shaft 20 to directly drive the third driving wheel 73 to rotate, since the third driving wheel 73 is fixedly connected with the second driving wheel 72 and the first driving wheel 71, the second driving wheel 72 and the first driving wheel 71 rotate with the third driving wheel 73, the second shift mechanism 31 drives the second limiting shaft 311 to make the shift protrusion 301a abut against the second clutch transmission assembly required to be output to make the corresponding driven gear in transmission connection with the transmission shaft 21, for example, the first driven gear 81 and the transmission shaft 21 are in transmission connection through the second clutch transmission assembly, the power is transmitted to the transmission shaft 21 through the first driven gear 81 to finally drive the toothed disc connected to the first power output end 211 of the transmission shaft 21 to output. In summary, since the third clutch transmission assembly is introduced between the third driving wheel 73 and the first power shaft 20, and combined with the first clutch transmission assembly between the first sun gear 53 and the first power shaft 20, the multi-stage driving wheel set 7 can provide two groups of different input speeds for the multi-stage driven gear set 8, and since the multi-stage driven gear set is three-stage in this embodiment, and each stage of gear can be in transmission connection with the transmission shaft 21 through the second clutch transmission assembly, the electric power-assisted transmission system can provide a total of 2x3=6 groups of different output speeds, effectively increasing the number of gear positions of the electric power-assisted transmission system, and providing users with more speed options.

[0130] Further, the multi-stage driving wheel set 7 of the embodiment further comprises a third planetary gear set 70, the third planetary gear set 70 comprising a second planet carrier 702, a second sun gear 704 and a plurality of third planetary gears 703; the inner wall of the first driving wheel 71 is provided with an inner tooth portion;

[0131] The second sun gear 704 is fixed on the housing 1;

[0132] The second carrier 702 is rotatably arranged on the first power shaft 20, and the plurality of third planetary gears 703 are arranged on the second carrier 702 and mesh with the second sun gear 704 and the inner tooth portion;

[0133] The fourth clutch transmission assembly is arranged between the first power shaft 20 and the second carrier 702;

[0134] The first shift mechanism 30 can drive the first limiting shaft 301 to make the shift protrusion 301a of the first limiting shaft 301 abut against the fourth clutch transmission assembly, so that the first power shaft 20 and the second carrier 702 are in transmission connection.

[0135] Specifically, the first driving wheel 71 has a stepped hole cavity structure formed inside, the second carrier 702 has a cylindrical structure connected with the first power shaft 20 and the fourth clutch transmission assembly and a connecting arm for arranging the plurality of third planetary gears 703, and the connecting arm is inclined along the axial direction; correspondingly, the connecting portion and the inner tooth portion of the first driving wheel 71 are arranged in the axial direction and are staggered with each other, so that after the second planetary gear set 6 is assembled between the first driving wheel 71 and the first power shaft 20, the cylindrical structure of the second carrier 702 is in the same vertical plane as the connecting portion and the second driving wheel 72, and the plurality of third planetary gears 703 are in the same vertical plane as the second sun gear 704 and the inner tooth portion, thereby fully utilizing the internal space of the first driving wheel 71 and improving the compactness and stability of the electric power-assisted variable speed system; in this embodiment, since the second sun gear 704 is fixed and the first driving wheel 71 is rotatable, when power is input by the second carrier 702 and the plurality of third planetary gears 703, the power must be output through the first driving wheel 71, i.e. driving the first driving wheel 71 to rotate; it should be noted that the system can be provided with different speed selection by setting the size relationship among the radii R1 of the revolution circles of the plurality of first planetary gears 52, the radii R2 of the revolution circles of the plurality of second planetary gears 60, and the radii R3 of the revolution circles of the plurality of third planetary gears 703, and the actual speed change requirement can be set, for example, when the radius R1 of the revolution circle of the plurality of first planetary gears 52 is equal to the radius R2 of the revolution circle of the plurality of second planetary gears 60, and the radius R1 of the revolution circle of the plurality of first planetary gears 52 is greater than the radius R3 of the revolution circle of the plurality of third planetary gears 703, i.e. the plurality of third planetary gears 703 can provide different input speeds for the plurality of multi-stage driving wheels 7 than the plurality of second planetary gears.

[0136] When the first shift mechanism 30 drives the first limiting shaft 301 to make the shift protrusion 301a abut against the fourth clutch transmission assembly, the first power shaft 20 is in transmission connection with the second planet carrier 702, power is transmitted into the first power input end 201 of the first power shaft 20, and then is enlarged by the second planet carrier 702 and the plurality of third planet gears 703 to drive the first driving wheel 71 to rotate. Since the third driving wheel 73 is fixedly connected with the second driving wheel 72 and the first rotating wheel, the second driving wheel 72 and the third driving wheel 73 rotate together with the first driving wheel 71. The second shift mechanism 31 drives the second limiting shaft 311 to make the shift protrusion 301a abut against the second clutch transmission assembly needed to be output, so that the corresponding driven wheel is in transmission connection with the transmission shaft 21, for example, the first driven wheel 81 is in transmission connection with the transmission shaft 21 through the second clutch transmission assembly, and then the power is transmitted to the transmission shaft 21 through the first driven wheel 81 to finally drive the toothed disc connected to the first power output end 211 of the transmission shaft 21 to output. In summary, since the fourth clutch transmission assembly is introduced between the second planet carrier 702 and the first power shaft 20, combined with the first clutch transmission assembly between the first sun gear 53 and the first power shaft 20 and the third clutch transmission assembly between the third driving wheel 73 and the first power shaft 20, the multi-stage driving wheel set 7 can provide three groups of different input speeds for the multi-stage driven wheel set 8. Since the multi-stage driven wheel set is three-stage in the embodiment, and each stage of gear can be in transmission connection with the transmission shaft 21 through the second clutch transmission assembly, the electric power-assisted transmission system can provide 3x3=9 groups of different output speeds in total, without changing the volume of the existing multi-stage driving wheel set 7, the number of transmission gears of the electric power-assisted transmission system is effectively increased.

[0137] Referring to the accompanying drawings Figure 5 , Figure 6 , Figure 12 , Figure 14 , Figure 15 and Figure 16 , the first power shaft 20 and the transmission shaft 21 are each provided with a mounting hole 200; the first clutch transmission assembly, the third clutch transmission assembly and the fourth clutch transmission assembly are each composed of a first pawl 90 and a first ratchet structure 91. The first pawl 90 is connected with an elastic sheet 94, and is assembled into the mounting hole 200 through the elastic sheet 94. The first ratchet structure 91 is arranged on the first sun gear 53, the third driving wheel 73 and the second planet carrier 702. When the shift protrusion 301a does not abut against the first pawl 90, the first pawl 90 is compressed by the elastic sheet and is in a retracted state and is not connected with the corresponding first ratchet structure 91. When the shift protrusion 301a abuts against the first pawl 90, the first pawl 90 is in an extended state and is in transmission connection with the corresponding first ratchet structure 91. A relief space is formed between the first pawl 90 and the mounting hole 200.

[0138] The second clutch transmission assembly is composed of a second pawl 92 and a second ratchet structure 93. The second pawl 92 is connected with an elastic sheet 94, and the second pawl 92 is assembled into the mounting hole 200 through the elastic sheet 94. The second ratchet structure 93 is arranged on each level of the multi-stage driven wheel set 8. When the second pawl 92 is not subjected to the abutment of the shift protrusion 301a, it is compressed by the elastic sheet 94 to be in a retracted state and is not connected with the corresponding second ratchet structure 93. When the second pawl 92 is subjected to the abutment of the shift protrusion 301a, it is in an extended state and can be in driving connection with the corresponding second ratchet structure 93. There is no space between the outer wall of the second pawl 92 and the inner wall of the mounting hole 200.

[0139] Specifically, the first clutch transmission assembly, the third clutch transmission assembly and the fourth clutch transmission assembly are distributed along the axial direction of the first power shaft 20 at the same interval. This not only realizes the compactness of the structural distribution, but also enables the first shift mechanism 30 to adopt a simpler instruction to control the movement of the first limiting shaft 301, that is, only the control of the movement of the first limiting shaft 301 by the same distance each time can realize the switching between different clutch transmission assemblies. Similarly, the second clutch transmission assembly is provided with three second clutch transmission assemblies corresponding to the three-stage driven wheels of the multi-stage driven wheel set 8, and the three second clutch transmission assemblies are distributed along the axial direction of the transmission shaft 21 at the same interval. Here, no longer be described in detail. In this embodiment, taking the third clutch transmission assembly on the first power shaft 20 as an example, the first power shaft 20 has a plurality of mounting holes 200 at the position corresponding to the third driving wheel 73. A plurality of first pawls 90 are correspondingly arranged on the mounting holes 200, and one end of the first pawl 90 is connected with the elastic sheet 94. The other end of the elastic sheet 94 is fixed on the side wall of the mounting hole 200. The axial direction of the mounting hole 200 is perpendicular to the axial direction of the first power shaft 20. The first pawl 90 can move along the axial direction of the mounting hole 200. When the first pawl 90 is not subjected to the abutment of the shift protrusion 301a, it is compressed by the elastic sheet 94 to be in a retracted state. When the first pawl 90 is subjected to the abutment of the shift protrusion 301a, it is in an extended state. The inner ring of the third driving wheel 73 is provided with a first ratchet structure 91. When the first power shaft 20 rotates in the positive direction as indicated by the arrow, the first pawl 90 is subjected to the abutment of the shift protrusion 301a, so that it establishes a driving connection with the first ratchet structure 91 on the third driving wheel 73, thereby driving the third driving wheel 73 to rotate together. When the first power shaft 20 rotates in the negative direction as indicated by the arrow, Figure 15 Figure 15 ​When rotating in the reverse direction of the arrow, the first pawl 90 is retracted into the clearance space due to the clearance between the first pawl 90 and the inner wall of the mounting hole 200, that is, the reverse rotation of the first power shaft 20 cannot drive the third driving wheel 73 to rotate, thereby avoiding the influence of the reverse pedaling of the pedal on the normal use of other transmission structures on the first power shaft 20 and the transmission shaft 21. The principles of the first clutch assembly and the fourth clutch assembly are the same as that of the third clutch assembly, and will not be described here. The second clutch assembly is different from the above three clutch assemblies, specifically, the second pawl 92 is thicker than the first pawl 91. When the second pawl 92 is assembled into the mounting hole 200 on the transmission shaft 21, the clearance between the second pawl 92 and the mounting hole 200 is only enough for the second pawl 92 to move in the axial direction of the mounting hole 200, and cannot swing in the radial direction, so that the multi-stage driven wheel set 8 can be driven to rotate in any direction, and conversely, when the bicycle is on a downhill or sliding, the rotation of the transmission shaft 21 will also drive the multi-stage driven wheel set 8 to rotate, thereby driving the multi-stage driving wheel set 7 to rotate, providing energy recovery for the electric assist module. The reverse rotation of the motor in the electric assist module charges the power supply part of the electric assist variable speed system. In addition, the second pawl 92 does not need to realize one-way rotation, which greatly reduces the processing cost of the second pawl 92.

[0140] In order to quickly convert the axially distributed first pawl 90 or second pawl 92 to the extended state when the shift protrusion 301a moves axially, a transition inclined wall 921 is arranged on the first pawl 90 and the second pawl 92. The shift protrusion 301a can easily convert the first pawl 90 or the second pawl 92 to the extended state by abutting against the transition inclined wall 921. In order to facilitate the connection stability between the elastic sheet 94 and the first pawl 90 or the second pawl 92, and to ensure that the first pawl 90 or the second pawl 92 can be quickly reset by the elastic sheet 94 when not abutted by the shift protrusion 301a, a groove 920 is arranged on the top of the first pawl 90 and the second pawl 92. One end of the elastic sheet 94 is embedded in the groove 921, and the other end of the elastic sheet 94 is fixed on the inner wall of the mounting hole 200.

[0141] Preferably, the first shift mechanism 30 and the second shift mechanism 31 each include a control module 302 and a control motor 303.

[0142] The first power shaft 20 and the transmission shaft 21 are internally provided with an axially extending threaded hole 202;

[0143] The outer wall of the first limiting shaft 301 and the second limiting shaft 311 is provided with an external thread for screwing with the threaded hole 202;

[0144] The first limiting shaft 301 and the second limiting shaft 311 are both internally provided with a connecting hole 301b penetrating in the axial direction, the connecting hole 301b is connected with the rotating shaft of the control motor 303, and the screw rod can move in the axial direction of the rotating shaft of the control motor 303;

[0145] The control module 302 is electrically connected with the control motor 303.

[0146] Since the first shifting mechanism 30 and the second shifting mechanism 31 adopt the same structure, the embodiment only describes the first shifting mechanism 30, in order to prevent the relative rotation between the first limiting shaft 301 and the rotating shaft of the control motor 303, in the embodiment, the cross section of the connecting hole 301b and the cross section of the rotating shaft of the control motor 303 are both hexagonal, when the control motor 303 is started to rotate the rotating shaft, since the connecting hole 301b and the rotating shaft of the control motor 303 cannot rotate relatively, and the first limiting shaft 301 is threadedly connected with the threaded hole 202 of the first power shaft 20, so that the first limiting shaft 301 generates a movement of displacement in the axial direction of the first power shaft 20, in other embodiments, the cross section of the connecting hole 301b and the cross section of the rotating shaft of the control motor 303 can also be selected as D-shaped, triangular and other special shapes. The control module 302 includes a battery 302b and a control board 302a, wherein the battery 302b and the control board 302a are arranged in the axial direction of the first power shaft 20, the control board 302a is located at the end position of the first power shaft 20, so that the wireless receiving element of the control board 302a is not hindered by the battery 302b and other elements, and the communication between the control board 302a and the external electronic equipment is smooth, specifically, three gear position instructions can be set in the control board 302a, the three gear position instructions are transmitted to the control motor 303, so that the rotating shaft of the control motor 303 generates rotation in a specified direction and a specified number of rotations, for example, the control board 302a sends the first gear position instruction to the control motor 303, so that the first limiting shaft 301 moves, so that the shifting convex part 301a thereof is located at the position of the first clutch transmission assembly, and drives the first clutch transmission assembly to be connected with the first sun gear 53, to establish the transmission connection between the first sun gear 53 and the first power shaft 20. As shown in the figure, in order to facilitate the assembly of the battery 302b and the control board 302a into the interior of the first power shaft 20, the control module 302 is also provided with a protective shell 302c, the protective shell 302c wraps the battery 302b and the control board 302a, and an elastic clamping convex part for clamping with the first power shaft 20 is arranged at the end of the protective shell 302c, so as to facilitate the disassembly and assembly of the control module 302 as a whole from the first power shaft 20. Figure 12

[0147] Referring to the accompanying drawings Figure 2 The shell 1 includes a left cover 102, a right cover 101 and a middle shell 103 with two open ends;

[0148] ​One end of the first power shaft 20 passes through the left cover 102 and is connected to the left cover 102 through a bearing, and the other end passes through the right cover 101 and is connected to the right cover 101 through a bearing; one end of the transmission shaft 21 is connected to the left cover 102 through a bearing, and the other end passes through the right cover 101 and is connected to the right cover 101 through a bearing; wherein the stator 40 of the motor set 4 is fixed on the left cover 102;

[0149] The left cover 102 and the middle shell 103 are sealingly connected at one end, and the right cover 101 and the middle shell 103 are sealingly connected at the other end.

[0150] In this embodiment, the transmission structure of the entire electric power-assisted variable speed system described above is sealed inside the shell 1, and the interface of the first power shaft 20 and the left cover 102 and the right cover 101 can be sealed with a sealing cover, and a sealing ring is arranged inside the sealing cover for further sealing. In use, it can avoid the entry of sand, dust and other objects into the transmission system to pollute or even affect the use of the transmission structure, and at the same time, it can achieve the effect of no cleaning and maintenance. After the bicycle is installed with the electric power-assisted variable speed system of the utility model, even if it is ridden on a muddy road, it is not afraid that the system will be damaged due to the entry of foreign matter, and it is especially suitable for mountain bikes.

[0151] Embodiment two:

[0152] Referring to the accompanying Figure 17 and the accompanying Figure 18 The electric power-assisted variable speed system further comprises a first reversing gear set 22, the first reversing gear set 22 comprising a plurality of reversing planetary gears 220, a transmission frame 221 and an output cylinder 222; the transmission frame 221 is provided with an axially staggered inner tooth ring 221a and a connecting ring 221b, and the transmission frame 221 is fixed on the transmission shaft 21 through the connecting ring 221b; a plurality of reversing planetary gears 220 are installed on the shell 1, and the reversing planetary gears 220 are engaged with the inner tooth ring 221a; the output cylinder 222 is rotatably installed on the transmission shaft 22, and one end of the output cylinder 222 is provided with an outer tooth part 222a for engaging with the reversing planetary gears 220, and the other end of the output cylinder 222 passes through the shell 1 and is provided with a second power output end 332b.

[0153] Specifically, when the electric power-assisted variable speed system is applied to a bicycle, the second power output end 332b of the output cylinder 332 can be used to install a sprocket; the inner wall of the connecting ring 221b of the transmission frame 221 is provided with a spline structure, and the outer wall of the transmission shaft 21 is provided with a transmission spline 212 connected with the connecting ring 221b, so that the rotation of the transmission shaft 21 can drive the transmission frame 221 to transmit power, and since the plurality of reversing planetary gears 220 are installed on the housing 1 and the output cylinder 222 is rotatably sleeved on the transmission shaft 21, the power is input through the transmission frame 221, the power is transmitted by the plurality of reversing planetary gears 220, and finally the power is output through the output cylinder 222. This way makes the rotation direction of the output cylinder 222 opposite to that of the transmission shaft 21. Since the transmission shaft 21 and the first power shaft 20 are driven by the gear external meshing mode, after the transmission of the first reversing gear set 22, the rotation direction of the output cylinder 222 is the same as that of the first power shaft 20, that is, in this embodiment, the rotation direction of the sprocket installed on the output cylinder 222 is the same as that of the first power shaft 20.

[0154] Embodiment three:

[0155] Referring to the accompanying Figure 19 -attached Figure 21The electric power-assisted derailleur system comprises a second reversing gear set 23, which comprises a transmission gear 231 and an output gear 230. The embodiment only describes the differences from the above-mentioned embodiment. The third power output end 230a is arranged on the output gear 230. Specifically, the third power output end 230a is an axial extension structure of the output gear 230. The transmission gear 231 is coaxially fixed on the transmission shaft 21. The output gear 230 is rotatably installed on the first power shaft 20 and is in mesh with the transmission gear 231. When the output gear 230 is assembled on the first power shaft 20, the third power output end 230a extends out of the shell 1 and is arranged. The third power output end 230a is used for connecting the sprocket of the bicycle and providing power for the wheel. In this embodiment, the output gear 230 can be assembled on the first power shaft 20 by the bearing mode. The bearing is also arranged between the output gear 230 and the shell 1, so that the rotation of the output gear 230 and the first power shaft 20 does not interfere with each other. In order to ensure the stable transmission of power, the transmission gear 231 is assembled on the transmission shaft 21 by the spline connection mode, so that the rotation of the transmission shaft 21 can drive the transmission gear 231 to rotate together. The transmission gear 231 and the output gear 230 are in mesh with each other, so that the rotation direction of the power output end 211 is opposite to that of the transmission shaft 21. Specifically, it can be compared with the first power output end 211 on the transmission shaft 21 in the first embodiment. The third power output end 230a is reversed due to the arrangement of the second reversing gear set 23. In summary, the power of this embodiment is provided by the first power input end 201 fixed on both ends of the first power shaft 20 or the motor set 4. The first power shaft 20 is driven to rotate, and the power is transmitted to the transmission shaft 21 through the multi-stage driving wheel set 7 and the multi-stage driven wheel set 8. The torque and the rotation speed after multi-stage speed change are transmitted to the transmission gear 231 through the transmission shaft 21. The transmission gear 231 and the output gear 230 are in mesh transmission to realize reversing. Finally, the power is transmitted out through the third power output end 230a fixed on the output gear 230.

[0156] Embodiment four:

[0157] This embodiment only describes the differences from the first embodiment. Refer to the drawings of the first embodiment Figure 22The electric power-assisted variable speed system comprises a second power shaft 24 and a support shaft 25 which is at least partially hollow, the support shaft 25 is rotatably installed in the housing 1 and is used to assemble the multi-stage driving wheel set 7 and the first gear shifting mechanism 30, the support shaft 25 in the embodiment plays the role of the first power shaft 20 in the first embodiment, the difference is that the two ends of the support shaft 25 do not extend out of the housing 1, while the two ends of the second power shaft 24 extend out of the housing 1 and are provided with a second power input end 241 for connecting a pedal, the electric power-assisted variable speed system is powered, and a coaxially assembled input gear 240 is arranged on the second power shaft 24, the input gear 240 is used to mesh with any stage of the multi-stage driving wheel set 7, when power is brought by the second power input end 241 to drive the second power shaft 24 to rotate, the input gear 240 meshes with the multi-stage driving wheel set 7 to change the rotating direction of the multi-stage driving wheel set 7, the multi-stage driving wheel set 7 needs to mesh with the multi-stage driven wheel set 8 to transmit power, and the rotating direction is changed for the second time, finally the rotating direction of the first power output end 211 is the same as that of the second power input end 241, in the embodiment, the second power shaft 24 and the support shaft 25 are arranged on different shafts, the input gear 240 arranged on the second power shaft 24 meshes with the multi-stage driving wheel set 7 on the support shaft 25 to change the rotating direction, the rotating direction of the first power output end 211 is the same as that of the second power input end 241, which is different from the rotating direction of the first power output end 211 being opposite to that of the first power input end 201 in the first embodiment, so that the electric power-assisted variable speed system can provide more various rotating directions.

[0158] In order to achieve one or part or all of the above purposes or other purposes, the utility model also proposes a bicycle, the bicycle includes the electric power-assisted variable speed system.

[0159] Obviously, the above described embodiments are only a part of the embodiments of the utility model, and are not all the embodiments, the preferable embodiments of the utility model are given in the drawings, but do not limit the patent range of the utility model. The utility model can be realized in many different forms, and contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the utility model more thorough and comprehensive. Although the utility model is explained in detail with reference to the foregoing embodiments, the skilled in the art can still modify the technical scheme recorded in the foregoing each specific embodiment or make equivalent replacement to part technical features. Any equivalent structure made by using the contents of the utility model specification and drawings, direct or indirect application in other related technical fields, are all within the patent protection range of the utility model.

Claims

1. An electrically assisted variable speed system characterised in that, The application relates to a power transmission device, which comprises a housing, a first power shaft, a first gear shifting mechanism, a transmission shaft, a second gear shifting mechanism, an electric power assisting module, a second planetary gear set, a multi-stage driving wheel set and a multi-stage driven wheel set. The first power shaft and the transmission shaft are rotatably connected to the housing, the first power shaft has a first power input end which extends out of the housing, and the transmission shaft has a first power output end which extends out of the housing. The electric power assisting module comprises a motor set and a first planetary gear set, the first planetary gear set comprises a driving gear, a first planet carrier and a plurality of first planet wheels which are rotatably arranged on the first planet carrier. The stator of the motor set is fixed to the housing, the rotor of the motor set is arranged in an axial hollow mode, the rotor is axially connected to the driving gear, the rotor is coaxially arranged with the first power shaft and has a spacing with the first power shaft. The first planetary gear set and the second planetary gear set share the same inner ring gear, and the inner ring gear is fixed to the housing. The first planet carrier is rotatably arranged on the first power shaft, the first planet carrier is axially provided with a first sun gear, the plurality of first planet wheels are rotatably arranged on the first planet carrier, and the first planet wheels are in mesh with the inner ring gear and the driving gear. The first power shaft is provided with a first clutch transmission assembly between the first power shaft and the first sun gear. The second planetary gear set has a plurality of second planet wheels, the plurality of second planet wheels are fixedly connected to the multi-stage driving wheel set, the second planet wheels are in mesh with the inner ring gear and the first sun gear, and the multi-stage driving wheel set is rotatably arranged on the first power shaft. The multi-stage driven wheel set is rotatably arranged on the transmission shaft, and the transmission shaft and the multi-stage driven wheel set are provided with a second clutch transmission assembly between each level. The first gear shifting mechanism has a movable first limiting shaft which extends into the first power shaft, the second gear shifting mechanism has a movable second limiting shaft which extends into the transmission shaft, and the first limiting shaft and the second limiting shaft are provided with gear shifting convex parts. The first gear shifting mechanism can drive the first limiting shaft to make the gear shifting convex part of the first limiting shaft abut against the first clutch transmission assembly, so that the first power shaft and the first sun gear are in transmission connection. The multi-stage driving wheel set comprises a first driving wheel, a second driving wheel, a third driving wheel and a plurality of limiting rods.

2. The electrically-assisted gear shifting system of claim 1, wherein, The first driving wheel is provided with a connecting part in an axial direction. The second driving wheel is sleeved on the connecting part and is coaxially fixed with the first driving wheel. The plurality of limiting rods are arranged corresponding to the plurality of second planet wheels, one end of the limiting rod penetrates the second planet wheel, the third driving wheel and the first driving wheel in sequence and is fixedly connected to the first driving wheel, and the first power shaft is provided with a third clutch transmission assembly between the first power shaft and the third driving wheel. The first gear shifting mechanism can drive the first limiting shaft to make the gear shifting convex part of the first limiting shaft abut against the third clutch transmission assembly, so that the first power shaft and the third driving wheel are in transmission connection. ​ The first driving wheel and the first driven wheel are engaged, the second driving wheel and the second driven wheel are engaged, and the third driving wheel and the third driven wheel are engaged.

3. The electrically-assisted gear shifting system of claim 2, wherein, The third planetary gear set comprises a second carrier, a second sun gear and a plurality of third planetary gears; and an inner wall of the first driving wheel is provided with an inner tooth portion; The second sun gear is fixed on the housing; The second carrier is rotatably arranged on the first power shaft, the plurality of third planetary gears are arranged on the second carrier, and the third planetary gears engage with the second sun gear and the inner tooth portion; The fourth clutch transmission assembly is arranged between the first power shaft and the second carrier; The first shift mechanism drives the first limiting shaft to make the shift protrusion of the first limiting shaft abut against the fourth clutch transmission assembly, so that the first power shaft and the second carrier are in transmission connection.

4. The electrically-assisted gear shifting system of claim 3, wherein, The first power shaft and the transmission shaft are both provided with mounting holes; the first clutch transmission assembly, the third clutch transmission assembly and the fourth clutch transmission assembly are all formed by a first pawl and a first ratchet structure; the first pawl is connected with an elastic sheet, and the first pawl is assembled into the mounting hole through the elastic sheet; the first ratchet structure is arranged on the first sun gear, the third driving wheel and the second carrier; when the first pawl is not abutted by the shift protrusion, the first pawl is compressed by the elastic sheet and is in a retracted state and is not connected with the corresponding first ratchet structure; when the first pawl is abutted by the shift protrusion, the first pawl is in an extended state and is in transmission connection with the corresponding first ratchet structure; and an avoiding space is formed between the first pawl and the mounting hole; The second clutch transmission assembly is formed by a second pawl and a second ratchet structure; the second pawl is connected with an elastic sheet, and the second pawl is assembled into the mounting hole through the elastic sheet; the second ratchet structure is arranged on each level of the multi-stage driven wheel set; when the second pawl is not abutted by the shift protrusion, the second pawl is compressed by the elastic sheet and is in a retracted state and is not connected with the corresponding second ratchet structure; when the second pawl is abutted by the shift protrusion, the second pawl is in an extended state and is in transmission connection with the corresponding second ratchet structure; and there is no avoiding space between the outer wall of the second pawl and the inner wall of the mounting hole.

5. The electrically-assisted shifting system of claim 3, wherein, The first shift mechanism and the second shift mechanism both comprise a control module and a control motor; The first power shaft and the transmission shaft are both provided with axially extending threaded holes; The outer wall of the first limiting shaft and the outer wall of the second limiting shaft are both provided with external threads which are in threaded connection with the threaded holes; The first limiting shaft and the second limiting shaft are both provided with axially penetrating connecting holes which are connected with the rotating shaft of the control motor, and the screw rod can move along the axial direction of the rotating shaft of the control motor; The control module is electrically connected with the control motor.

6. The electrically-assisted shifting system of claim 4, wherein, The first pawl and the second pawl are both provided with grooves which are connected with the elastic sheets; the first pawl and the second pawl are both provided with transition inclined walls which can be abutted by the shift protrusion when the shift protrusion moves axially.

7. The electrically-assisted shifting system of claim 3, wherein, The connecting portion is an axial protrusion connected to the first driving wheel, and the outer wall of the axial protrusion and the inner wall of the second driving wheel are provided with interfitting splines.

8. The electrically-assisted gear shifting system of claim 7, wherein, The housing comprises a left cover, a right cover and a middle shell with two open ends; One end of the first power shaft passes through the left cover and is connected to the left cover through a bearing, and the other end passes through the right cover and is connected to the right cover through a bearing; one end of the transmission shaft is connected to the left cover through a bearing, and the other end passes through the right cover and is connected to the right cover through a bearing; wherein the stator of the motor set is fixed on the left cover; The left cover and the middle shell are sealingly connected at one end opening, and the right cover and the middle shell are sealingly connected at the other end opening.

9. The electrically-assisted gear shifting system of claim 8, wherein, Further comprising a first reversing gear set, the first reversing gear set comprising a plurality of reversing planetary gears, a transmission frame and an output cylinder; The transmission frame is provided with an axially offset inner ring and a connecting ring, and the transmission frame is fixed to the transmission shaft through the connecting ring; A plurality of reversing planetary gears are mounted on the housing, and the reversing planetary gears are meshed with the inner ring; The output cylinder is rotatably mounted on the transmission shaft, and one end of the output cylinder is provided with an outer tooth part for meshing with the reversing planetary gears, and the other end of the output cylinder passes through the housing and is provided with a second power output end.

10. An electrically assisted variable speed system characterized by, It comprises: a housing, a first power shaft which is at least partially hollow, a first gear shifting mechanism, a transmission shaft which is at least partially hollow, a second gear shifting mechanism, an electric power assisting module, a second planetary gear set, a multi-stage driving wheel set, a multi-stage driven wheel set and a second reversing gear set; The first power shaft and the transmission shaft are both rotatably connected to the housing, and the first power shaft has a first power input end which extends out of the housing at both ends; The second reversing gear set comprises a transmission gear and an output gear, the transmission gear is coaxially fixed on the transmission shaft, and the output gear is rotatably mounted on the first power shaft and meshed with the transmission gear; The output gear is provided with an axially extending third power output end which extends out of the housing; The electric power assisting module comprises a motor set and a first planetary gear set; the first planetary gear set comprises a driving gear, a first planet carrier and a plurality of first planetary gears rotatably arranged on the first planet carrier; The stator of the motor set is fixed on the housing, and the rotor of the motor set is axially hollowly arranged, the rotor is axially connected to the driving gear, the rotor is coaxially distributed with the first power shaft, and there is a spacing between the rotor and the first power shaft; The first planetary gear set and the second planetary gear set share the same inner ring gear, and the inner ring gear is fixed on the housing; The first planet carrier is rotatably arranged on the first power shaft, and the first planet carrier is axially provided with a first sun gear; a plurality of first planetary gears are rotatably mounted on the first planet carrier, and the first planetary gears mesh with the inner ring gear and the driving gear; The first power shaft and the first sun gear are provided with a first clutch transmission assembly therebetween; The second planetary gear set has a plurality of second planetary gears, the plurality of second planetary gears are fixedly connected with the multi-stage driving wheel set, and the second planetary gears mesh with the inner ring gear and the first sun gear; the multi-stage driving wheel set is rotatably arranged on the first power shaft; The multi-stage driven wheel set is rotatably arranged on the transmission shaft, and the transmission shaft and the multi-stage driven wheel set are each provided with a second clutch transmission assembly therebetween; The first shift mechanism has a movable first limiting shaft extending into the first power shaft, and the second shift mechanism has a movable second limiting shaft extending into the transmission shaft; the first limiting shaft and the second limiting shaft each have a shift protrusion; The first shift mechanism can drive the first limiting shaft to make the shift protrusion abut against the first clutch transmission assembly, so that the first power shaft and the first sun gear are in transmission connection; the second shift mechanism can drive the second limiting shaft to make the shift protrusion abut against any one of the second clutch transmission assemblies, so that the corresponding driven gear and the transmission shaft are in transmission connection.

11. An electrically assisted variable speed system characterized by, Comprise: a housing, a support shaft which is at least partially hollow, a first shift mechanism, a transmission shaft which is at least partially hollow, a second shift mechanism, an electric power assisting module, a second planetary gear set, a multi-stage driving gear set, a multi-stage driven gear set and a second power shaft; The second power shaft, the support shaft and the transmission shaft are all rotatably connected to the housing, and the transmission shaft has a power output end extending out of the housing; the second power shaft has a second power input end extending out of the housing at both ends, and the second power shaft is provided with an input gear; The electric power assisting module comprises a motor set and a first planetary gear set; the first planetary gear set comprises a driving gear, a first carrier and a plurality of first planet gears rotatably arranged on the first carrier; The stator of the motor set is fixed on the housing, and the rotor of the motor set is hollowly arranged in the axial direction; the rotor is connected to the driving gear in the axial direction, and the rotor and the support shaft are coaxially distributed with a spacing therebetween; The first planetary gear set and the second planetary gear set share the same inner ring gear, and the inner ring gear is fixed on the housing; The first carrier is rotatably arranged on the support shaft, and the first carrier is provided with a first sun gear in the axial direction; the plurality of first planet gears are rotatably mounted on the first carrier, and the first planet gears mesh with the inner ring gear and the driving gear; The support shaft and the first sun gear are provided with a first clutch transmission assembly therebetween; The second planetary gear set has a plurality of second planet gears, and the plurality of second planet gears are fixedly connected to the multi-stage driving gear set and mesh with the inner ring gear and the first sun gear; The multi-stage driving gear set is rotatably arranged on the support shaft, and any stage of the multi-stage driving gear set can mesh with the input gear; The multi-stage driven gear set is rotatably arranged on the transmission shaft, and each stage of the multi-stage driven gear set and the transmission shaft is provided with a second clutch transmission assembly therebetween; The first shift mechanism has a movable first limiting shaft extending into the support shaft, and the second shift mechanism has a movable second limiting shaft extending into the transmission shaft; the first limiting shaft and the second limiting shaft each have a shift protrusion; The first shift mechanism can drive the first limiting shaft to make the shift protrusion abut against the first clutch transmission assembly, so that the support shaft and the first sun gear are in transmission connection; the second shift mechanism can drive the second limiting shaft to make the shift protrusion abut against any one of the second clutch transmission assemblies, so that the corresponding driven gear and the transmission shaft are in transmission connection.

12. A bicycle characterized in that, The bicycle comprises the electrically assisted gear shifting system according to any one of claims 1 to 11. The bicycle comprises the electrically assisted gear shifting system according to any one of claims 1 to 11.

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