WO2021129066A1

WO2021129066A1 - Central drive device and bicycle having said device

Info

Publication number: WO2021129066A1
Application number: PCT/CN2020/121355
Authority: WO
Inventors: 黄福明; 黄俊燚; 范清泉; 蔡华林; 黄俊宁
Original assignee: 苏州万佳电器有限公司
Priority date: 2019-12-28
Filing date: 2020-10-16
Publication date: 2021-07-01
Also published as: CN110949597A

Abstract

A central drive device and a bicycle having said device. The central drive device comprises a housing, a motor (1) provided in the housing, a speed reduction mechanism, a central shaft (11) and a crankset device, the speed reduction mechanism being in transmission connection with the motor (1), the central shaft (11) being used for being connected to a pedal device and being rotatably provided in the housing, and said device further comprises a first clutch (5); the first clutch (5) has one end connected to an output end of the speed reduction mechanism, and the other end connected to the crankset device; the first clutch (5) comprises a transmission state and a release state; the crankset device is connected to the central shaft (11) by means of a second clutch (7), such that the central shaft (11) drives the crankset device to rotate; in a power-assist operating mode, the first clutch (5) enables transmission connection between the output end of the speed reduction mechanism and the crankset device, such that the output end transmits power to the crankset device; and in a non-power-assist operating mode, the first clutch (5) disconnects the power connection between the output end of the speed reduction mechanism and the crankset device. Such a central drive device can enable a person to pedal a bicycle in a lighter and less laborious manner.

Description

Mid-drive device and bicycle with the device

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on December 28, 2019, the application number is 201911384357.3, and the invention title is "a central drive device and a bicycle with the device", the entire content of which is incorporated by reference Incorporated in this application.

Technical field

The invention relates to the technical field of vehicle design, and more specifically, to a mid-drive device. In addition, the present invention also relates to a bicycle including the above-mentioned central drive device.

Background technique

In the prior art, the mid-drive device of a power-assisted bicycle generally includes a motor, and a first-stage and a second-stage reduction gear connected to the motor. The output gear of the second-stage reduction gear finally drives the chainring to rotate, thereby assisting the bicycle. .

In the transmission path from the motor to the chainring, a clutch is generally set between the first-stage reduction gear and the second-stage reduction gear. It is used when the motor stops or does not start when the motor is powered off and needs to be stepped on by pure human power. Disconnect the motor and the first-stage reduction gear, so as to realize the function of the assisted bicycle as an ordinary bicycle.

Due to the structure and space limitations of the secondary reduction gears, the clutches that can be selected are usually small in size. At the same time, because the clutches are commonly used as standard parts, and the smaller the size, the smaller the load-bearing torque. Therefore, the space limitation is often not conducive to the improvement of the motor's drive assist capacity .

More importantly, when the motor is powered off or does not start, the chainring rotates when the motor is stepped on by pure human power. The second-stage reduction mechanism and the chainring are connected together, and the chainring will drive the second-stage reduction gear to participate in the rotation movement. In this state, the human riding work is not all fed back to the rotation of the chainring, and part of the force is transmitted to the gear work, that is, the second-stage reduction gear mechanism becomes an additional load.

In summary, how to provide a central drive device with a clutch that is not limited by the space of the deceleration mechanism and is more efficient in human pedaling is a problem to be solved by those skilled in the art.

Summary of the invention

In view of this, the object of the present invention is to provide a mid-drive device that can have a high efficiency when pedaling purely by manpower and reduce the load in a state of purely manpower riding.

Another object of the present invention is to provide a bicycle including the above-mentioned central drive device.

In order to achieve the above objectives, the present invention provides the following technical solutions:

A mid-drive device includes a housing, a motor arranged in the housing, a reduction mechanism, a central shaft, and a chainring device. The reduction mechanism is in transmission connection with the motor; the central shaft is used to connect a pedaling device, And rotatably arranged in the housing; further comprising a first clutch, one end of the first clutch is connected to the output end of the reduction mechanism, the other end of the first clutch is connected to the crank device, the first clutch Including the transmission state and the disengaged state. When the first clutch is in the transmission state, the central drive device is in a booster working mode; when the first clutch is in the disengaged state, the central drive device is in a non-assisted working mode mode;

The chainring device and the bottom bracket are connected by a second clutch, so that the bottom bracket drives the chainring device to rotate;

In the assist working mode, the first clutch transmission connects the output end of the reduction mechanism and the chainring device, so that the output end transmits power to the chainring device;

In the non-assist working mode, the first clutch disconnects the power connection between the output end of the speed reduction mechanism and the crankset device.

Preferably, the crankset device includes a crankset and a crankset support provided with the crankset;

The reduction mechanism includes an output gear, the output gear has the output end, the first clutch is a one-way clutch, one side of the first clutch is connected to the output end of the reduction mechanism, and the first clutch The other side is connected with the crankset support for realizing the connection or disconnection of the output gear and the crankset support.

Preferably, the first clutch includes a one-way needle roller clutch or a wedge-type one-way clutch.

Preferably, the first clutch is a one-way needle roller clutch, comprising an outer ring and an inner ring, the outer ring is in interference fit with the inner hole of the output gear, and the inner ring is connected to the chain ring support ；

Or, the first clutch is a wedge-type one-way clutch, including an outer ring, a wedge, a retaining elastic member, and an inner ring. The outer ring is in clearance fit with the inner hole of the output gear, and the inner ring is in clearance fit with the inner hole of the output gear. The chain support is connected.

Preferably, the side of the output gear close to the chain ring is supported on the housing through a first bearing.

Preferably, the side of the crankset support close to the crankset is supported on the housing through a third bearing;

The side of the crankset support away from the crankset is supported on an end cover of the crankset support through a second bearing, and the end cover of the crankset support is fixed on the housing.

Preferably, the output end of the motor is an output shaft of the motor, and the reduction mechanism includes:

The first gear is arranged on the output shaft of the motor;

A gear shaft, the gear shaft is rotatably arranged inside the housing;

A second gear, the second gear meshes with the first gear for transmission, and the second gear is fixed to the gear shaft;

The third gear is fixed or integrally formed on the gear shaft, and the third gear meshes with the output gear for transmission, and is used for transmitting the output of the reduction mechanism to the output gear.

Preferably, the second gear is a plastic gear.

Preferably, a shaft sleeve is fixed on the inner circumference of the second gear, and the shaft sleeve is press-fitted or integrally formed with the second gear, and the shaft sleeve is fixed to the gear shaft.

A bicycle includes a central drive device, and the central drive device is the central drive device described in any one of the above.

A first clutch is arranged between the output end of the deceleration mechanism and the chainring device. The first clutch has two working states: a transmission state and a disengaged state, which correspond to the assisted working mode and the non-assisted working mode of the bicycle, respectively.

In the assist mode, the output end of the deceleration mechanism outputs power to the first clutch. The output end of the first clutch is connected to the chainring device and transmits power. The power output by the deceleration mechanism can be transmitted to the chainring device through the first clutch. Thus, the above-mentioned power transmission is realized; wherein the steering that the output end provides power to the first clutch is a steering that can lock the first clutch to transmit power.

In the non-assist working mode, the motor is in a power-off or non-starting state, and the transmission power to the first clutch is zero, and it will not drive the chainring device to rotate. At this time, the bottom shaft connected to the pedaling device will assist the power through the second clutch Convey to the chainring device to rotate the chainring device in the forward direction. Since the first clutch disconnects the output end of the deceleration mechanism from the chainring device, the rotation force of the chainring device is prevented from being distributed to the rotation of the drive output end, which can save the input power of the pedaling device and make riding more labor-saving.

In this application, in the power-assisted working mode, the motor is powered off or does not start, and the internal deceleration mechanism and the motor are not involved in the work. The chainring device is driven to rotate by pure human pedaling. The one-way transmission effect of the first clutch makes the chainring at this time The device is disconnected from the deceleration mechanism, and the force exerted by the person is directly fed back to the rotation of the chainring, and will not act on the deceleration mechanism, so as to avoid distributing the manpower to the rotation of the deceleration mechanism, making the bicycle lighter when pedaling. Effortless. The application also provides a bicycle including the above-mentioned central drive device.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative work.

FIG. 1 is a schematic diagram of the central drive device provided by this application.

In Figure 1:

1 is the motor, 2 is the motor output shaft, 3 is the output gear, 4 is the first bearing, 5 is the first clutch, 6 is the crankshaft support, 7 is the second clutch, 8 is the second bearing, and 9 is the crank The support end cover, 10 is a chain ring, 11 is a central shaft, 12 is a shaft sleeve, 13 is a gear shaft, and 14 is a second gear.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

The core of the present invention is to provide a mid-drive device, which can have higher efficiency when pedaling purely by manpower and reduce the load in the state of purely manpower riding.

Another core of the present invention is to provide a bicycle including the above-mentioned central drive device.

Please refer to FIG. 1, which is a schematic diagram of the central drive device provided by this application;

The present application provides a central drive device, which includes a housing, a motor 1, a reduction mechanism, a central shaft 11, a chainring device, a first clutch 5, and a second clutch.

Among them, the motor 1 is arranged in the housing, the central axis is connected to the pedaling device, and is arranged in the housing; the speed reduction mechanism is in driving connection with the output end of the motor 1, and the crank device is in driving connection with the output end of the speed reduction mechanism.

One end of the first clutch 5 is connected to the output end of the deceleration mechanism, and the other end of the first clutch 5 is connected to the crankset device. The first clutch 5 includes the transmission state and the disengaged state. When the first clutch 5 is in the rotating state, the central drive device is in Power-assisted working mode; when the first clutch 5 is in a disengaged state, the central drive device is in a non-assisted working mode;

Specifically, the crankset device and the bottom bracket 11 are connected through the second clutch 7.

In the power-assisted working mode, that is, when driven by the motor 1, the first clutch 5 connects the output end of the deceleration mechanism with the chainring device, so that the output end transmits power to the chainring device;

In the non-assisted working mode, that is, when the motor 1 stops output, the first clutch 5 disconnects the power connection between the output end of the deceleration mechanism and the chainring device.

The housing of the mid-drive device can be a mounting housing outside the motor 1 or a housing for setting the drive system of the bicycle. A motor 1, a deceleration mechanism, a chainring device and other devices are arranged in the housing.

Among them, the motor 1 is used as a power structure, and its output end may be in the form of an output shaft. The deceleration mechanism can be a two-stage deceleration mechanism or a multi-stage deceleration device. The structure and form of the deceleration mechanism can be selected from common deceleration mechanisms in the prior art, and compact structure is the selection requirement.

The crankset device includes a crankset 10 and a crankset support 6 for installing the crankset. The crankset 10 can be partially or fully installed on the outside of the housing. Please refer to Figure 1, where the fixed part of the crankset 10 is set on the crankset. The rest of the support 6 can protrude from the shell.

The transmission direction is that the output power of the motor is transmitted to the reduction mechanism, and the reduction mechanism is connected to the chainring device, and then drives the rotation of the chainring, provides power, and completes the entire transmission chain of the bicycle.

A first clutch 5 is arranged between the output end of the speed reduction mechanism and the chainring device. The first clutch 5 has two working states, including a transmission state and a disengaged state. When the first clutch 5 is in the transmission state, the central drive device is in the power-assisted working mode; when the first clutch 5 is in the disengaged state, the central drive device is in the non-power-assisted working mode.

In the assist mode, the output end of the deceleration mechanism outputs power to the first clutch 5. The output end of the first clutch 5 is connected to the chainring device and transmits the power. The power output by the deceleration mechanism can be transmitted to the teeth through the first clutch 5. A disc device, thereby realizing the above-mentioned power transmission; wherein the steering that the output end provides power to the first clutch 5 is a steering that can lock the first clutch to transmit power.

In the non-assisted working mode, the motor is in a power-off or non-starting state, and the power transmitted to the first clutch 5 is zero, and cannot drive the chainring device to rotate. At this time, the central shaft 11 connected to the pedaling device passes the assisted power through the second The clutch 7 is conveyed to the chain ring device, so that the chain ring device rotates in the forward direction. Optionally, the first clutch 5 is a one-way clutch, and the above-mentioned rotation of the chainring device causes the first clutch 5 to be in a slipping state, thereby disconnecting the output end of the deceleration mechanism from the chainring device and avoiding the rotational force of the chainring device Distributed to the rotation of the drive output end can save the input power of the pedaling device, making riding more labor-saving.

In this application, in the non-assist mode, the motor is powered off or does not start, and the internal deceleration mechanism and the motor are not involved in the work. The crankset device is driven to rotate by pure human pedaling, and the first clutch disconnects the crankset device from the deceleration mechanism. All the forces exerted by humans are directly fed back to the rotation of the chainring, and will not act on the deceleration mechanism, so as to avoid dispersing the manpower to drive the rotation of the deceleration mechanism, making it lighter and less laborious when pedaling the bicycle.

On the basis of the above-mentioned embodiment, the crankset device includes a crankset 10 and a crankset support 6 provided with the crankset 10;

The deceleration mechanism includes an output gear 3, the output gear 3 has the above-mentioned output end, the first clutch 5 is a one-way clutch, one side of the first clutch 5 is connected with the output end 3, and the other side of the first clutch 5 is connected to the crank 10 The chainring support 6 is connected to realize the connection or disconnection of the output gear 3 and the chainring support 6.

It should be noted that, in addition to the crankset 10 and the crankset support 6, the crankset device also includes other connection devices, and only the connection between the two is described in this application. In addition, the two sides of the first clutch 5 respectively refer to the inner ring and the outer ring that are relatively rotating as a one-way clutch.

The output end of the deceleration mechanism may be a gear, or a worm gear or other devices for driving the crankset support 6 to rotate, and other transmission connection structures in the prior art may be adopted.

Different sides of the first clutch 5 are respectively connected to the output gear 3 and the chain ring support 6. When the first clutch 5 is in different working states, the output gear 3 and the chain ring support 6 are connected and disconnected. The connection state refers to It means that the two can be engaged with each other for transmission, or other ways of connecting transmission, etc. Disconnect refers to the state of the two being separated from each other and slipping, so that the power cannot be transmitted to each other, no matter whether it is forward or reverse.

In this embodiment, the chainring support 6 is used to connect the first clutch 5 to avoid the inconvenience of the structure of the chainring 10 being set close to the first clutch 5. At the same time, the output gear 3 is used to transmit to the chainring bracket 6, and the gear transmission is reliable. It is flexible and easy to install.

On the basis of the above embodiment, the first clutch 5 is a one-way needle roller clutch or a wedge-type one-way clutch.

It should be noted that there are many types of one-way clutches, and the selection needs to satisfy the use mode of the first clutch 5 of the present application.

In a specific embodiment, the first clutch 5 is a one-way needle roller clutch, including an outer ring and an inner ring, the outer ring is in interference fit with the inner hole of the output gear 3, and the inner ring is connected with the chain ring support 6.

In a specific embodiment, the first clutch 5 is a wedge-type one-way clutch, including an outer ring, a wedge, a retaining elastic member, and an inner ring. The outer ring is in clearance fit with the inner hole of the output gear 3, and the inner ring and the teeth The disc support 6 is connected.

Correspondingly, the aforementioned second clutch 7 may be a one-way needle roller clutch. Specifically, the inner ring of the second clutch 7 is connected to the central shaft 11, and the outer ring is connected to the crankset support 6.

In the assist mode, the output end of the deceleration mechanism rotates clockwise, the outer ring of the first clutch 5 rotates clockwise, driving the inner ring of the first clutch 5 to rotate clockwise, so that the chainring device rotates clockwise to achieve forward movement.

In the non-assisted state, the deceleration mechanism has no output, the bottom bracket 11 rotates clockwise, driving the inner ring of the second clutch 7 to rotate clockwise, the second clutch 7 is locked, so that the outer ring also rotates clockwise, and the chainring device rotates clockwise. Turning the hour hand realizes advancement. At the same time, because the chainring device rotates clockwise, the first clutch 5 slips, thereby disconnecting from the output end of the deceleration mechanism.

In this embodiment, the central shaft 11 is used as the center of rotation, and a chainring support 6 is sleeved on it. The outer ring of the chainring support 6 is fixed with the inner ring of the first clutch 5, and the outer ring of the first clutch 5 Fixed with the inner ring of the output gear 3, a one-way needle roller clutch or a wedge-type one-way clutch can be conveniently sleeved between the output gear 3 and the chainring support 6, and the structure occupies a small space.

On the basis of the above-mentioned embodiment, the side of the output gear 3 close to the chain ring 10 is supported on the housing through the first bearing. That is, the side of the output gear 3 close to the crankset 10 is rotatably arranged on the housing through the first bearing 4.

On the basis of any of the above embodiments, the side of the chain support 6 close to the chain ring 10 is supported on the shell by a third bearing; the side of the chain support 6 far away from the chain ring 10 is supported on the housing by a second bearing 8 The crankset support end cover 9 is fixed on the shell.

That is to say, the crankset support 6 is rotatably arranged on the housing through the third bearing, and is rotatably disposed on the crankset support end cover 9 through the second bearing 8, and the crankset support end cover 9 is fixed on the On the shell.

It should be noted that the output gear 3 is rotatably arranged on the housing, so a rotating connection piece, such as a bearing, needs to be arranged at the end or the middle of the output gear.

The crankset support 6 is also rotatably arranged inside the housing, and can also be set by bearings. Please refer to Figure 1, where both ends of the crankset support 6 are supported on the housing by a second bearing and another bearing, respectively.

Optionally, between the crankset support 6 and the central shaft 11, other clutches that facilitate the one-way rotation of the crankset support 6 relative to the central shaft 11 can also be provided.

On the basis of the foregoing embodiment, the speed reduction mechanism is a two-stage speed reduction mechanism or a multi-stage speed reduction mechanism, and the transmission gear in the speed reduction mechanism is a plastic part.

On the basis of any of the above embodiments, the output end of the motor 1 is the motor output shaft 2, and the reduction mechanism specifically includes: a first gear, a gear shaft 13, a second gear 14, and a third gear.

The first gear is arranged on the motor output shaft 2, the gear shaft 13 is rotatably arranged inside the housing, the second gear 14 meshes with the first gear for transmission, and the second gear 14 is fixed on the gear shaft 13,

The third gear is fixed on the gear shaft 13 or integrally formed with the gear shaft 13, and the third gear meshes with the output gear 3 to transmit the output of the reduction mechanism to the output gear 3.

The above-mentioned second gear 14 may be configured as a plastic part to reduce noise. The second gear 14 is upstream, with a high speed and a small torque. The high speed will cause high noise, and the replacement of plastic parts will greatly reduce the noise.

Specifically, a shaft sleeve 12 is fixed on the inner circumference of the second gear 14, the sleeve 12 and the second gear 14 are press-fitted or integrally formed, and the shaft sleeve 12 is fixed to the gear shaft 13.

On the basis of any of the above embodiments, the sleeve 12 is a metal piece.

This application provides a specific embodiment. Please refer to FIG. 1. The mid-drive device includes a motor 1, a two-stage reduction gear mechanism, and a chain ring 10. The output end of the motor 1 is connected to a two-stage reduction gear mechanism. The mechanism drives the crankset support 6 and then drives the crankset 10 to rotate, so that the motor assists pedaling.

Specifically, the two-stage gear reduction mechanism includes a first-stage gear reduction and a second-stage gear reduction. The first-stage gear reduction includes a first gear arranged on the motor output shaft 2 or integrally formed with the motor output shaft 2, and a A second gear 14 meshes with a gear. The first gear and the second gear 14 form a one-stage reduction.

The second-stage gear reduction mechanism includes a gear shaft 13, which can be indirectly connected with the second gear 14 through a sleeve 12, or the gear shaft 13 and the second gear 14 are integrally formed, and the gear shaft 13 is provided with a third gear , The third gear meshes with the output gear 3 to form a second-stage deceleration. Optionally, the third gear is integrally formed with the gear shaft 13 or fixedly arranged on the gear shaft 13.

Specifically, the second gear 14 may be a plastic part, and the selection of a plastic material can reduce noise.

In order to solve the problem of the connection strength and position accuracy of the plastic gear 14 and the gear shaft, optionally, a sleeve 12 is provided between the second gear 14 and the gear shaft 13, and the sleeve 12 is tightly matched with the second gear or is integrally formed. The sleeve 12 is tightly fitted or sleeved with the gear shaft 13. The shaft sleeve 12 is a metal piece, which ensures the connection strength and ensures torque transmission.

The outer part of the output gear 3 is in meshing transmission connection with the gear shaft 13, and the inner ring of the output gear is provided with a first clutch 5 to realize the connection with the crankset support 6.

The output gear 3 has two end faces, and a first bearing 4 is arranged near one end face of the chain ring 10. Specifically, a ball bearing can be selected. The inner ring of the first bearing 4 is connected to the output gear 3, specifically, it is sleeved on the output gear 3 or On the shaft where the output gear 3 is located, the outer ring of the first bearing 4 is connected to the housing, specifically fixed on the housing; the end of the chainring support 6 close to and used to connect the chainring 10 is also fixed on the housing by arranging a bearing. The outer ring of the bearing is also connected to the housing.

The first clutch 5 is arranged between the output gear 3 and the chain ring support 6, and is used to disconnect the chain ring support 6 when the motor 1 is powered off or does not start, and pure human power is required to drive the chain ring 10 to rotate clockwise. The transmission connection with the output gear 3 prevents the gear transmission system (including all the parts of the two-stage gear reduction mechanism) and the motor rotor from being driven by the manpower during riding. Compared with the prior art, the load parts in this working mode are reduced, That is, all the parts of the second-stage gear reduction mechanism.

In the present invention, a first clutch 5 is cleverly arranged between the crankset support 6 and the output gear 3, so that when the motor 1 is powered off or does not start, the crankset 10 is driven to rotate clockwise by pure human power. The support 6 can rotate independently from the output gear 3; on the contrary, when the motor 1 starts, the output gear 3 locks the chainring support 6 through the engagement of the first clutch 5, and the two move synchronously to transmit the torque of the motor 1 to the chainring. , Assist human riding.

In addition, in order to fix the chain ring support 6 more stably, a bearing is also provided on the other end surface of the chain ring support 6 away from the chain ring 10, that is, the second bearing 8 in FIG. 1 and the inner ring of the second bearing 8 The crankset support 6 is connected, the outer ring is fixed on the shell through the crankset support end cover 9, and the second bearing 8 is connected with the crankset support end cover 9 by interference fit.

In addition to the mid-drive device provided in the foregoing embodiments, the present invention also provides a bicycle including the mid-drive device disclosed in the foregoing embodiments. Please refer to the prior art for the structure of the other parts of the bicycle, which will not be repeated here.

The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other.

The mid-drive device provided by the present invention and the bicycle with the mid-drive device have been described in detail above. Specific examples are used in this article to illustrate the principle and implementation of the present invention. The description of the above examples is only used to help understand the method and core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

A mid-drive device, comprising a housing, a motor (1) arranged in the housing, a speed reduction mechanism, a central shaft (11) and a chainring device, and the speed reduction mechanism is in transmission connection with the motor (1); The middle shaft (11) is used to connect the pedaling device, and is rotatably arranged in the housing; it is characterized in that:

It also includes a first clutch (5), one end of the first clutch (5) is connected to the output end of the speed reduction mechanism, the other end of the first clutch (5) is connected to the crank device, the first clutch (5) Including the transmission state and the disengaged state. When the first clutch (5) is in the transmission state, the central drive device is in the power-assisted working mode; when the first clutch (5) is in the disengaged state, the The mid-drive device is in a non-assist working mode;

The chainring device and the bottom shaft (11) are connected by a second clutch (7), so that the bottom shaft (11) drives the rotation of the chainring device;

In the assist working mode, the first clutch (5) drivingly connects the output end of the deceleration mechanism and the chainring device, so that the output end transmits power to the chainring device;

In the non-assist working mode, the first clutch (5) disconnects the power connection between the output end of the speed reduction mechanism and the chainring device.
The central drive device according to claim 1, characterized in that the crankset device comprises a crankset (10) and a crankset support (6) provided with the crankset (10);

The deceleration mechanism includes an output gear (3), the output gear (3) has the output end, the first clutch (5) is a one-way clutch, and one side of the first clutch (5) is connected to the deceleration The output end of the mechanism is connected, and the other side of the first clutch (5) is connected with the chain ring support (6) for realizing the output gear (3) and the chain ring support (6) Connected or disconnected.
The mid-drive device according to claim 2, wherein the first clutch (5) comprises a one-way needle roller clutch or a wedge-type one-way clutch.
The central drive device according to claim 3, characterized in that the first clutch (5) is a one-way needle roller clutch, comprising an outer ring and an inner ring, and the outer ring and the output gear (3) The inner hole is interference fit, and the inner ring is connected with the chainring support (6);

Or, the first clutch (5) is a wedge-type one-way clutch, including an outer ring, a wedge, a retaining elastic member and an inner ring, and the outer ring is in clearance fit with the inner hole of the output gear (3), The inner ring is connected with the crankset support (6).
The mid-drive device according to claim 4, characterized in that the side of the output gear (3) close to the crankset (10) is supported on the housing by a first bearing.
The central drive device according to claim 4, characterized in that the side of the crankset support (6) close to the crankset (10) is supported on the housing by a third bearing;

The side of the crankset support (6) away from the crankset (10) is supported on the crankset support end cover (9) through a second bearing (8), and the crankset support end cover (9) ) Is fixed on the housing.
The mid-drive device according to any one of claims 2 to 6, wherein the output end of the motor (1) is a motor output shaft (2),

The speed reduction mechanism includes:

The first gear is arranged on the motor output shaft (2);

A gear shaft (13), the gear shaft (13) is rotatably arranged inside the housing;

A second gear (14), the second gear (14) meshes with the first gear for transmission, and the second gear (14) is fixed to the gear shaft (13);

The third gear is fixed or integrally formed on the gear shaft (13), the third gear meshes with the output gear (3) for transmission, and is used to transmit the output of the reduction mechanism to the output gear (3) .
The central drive device according to claim 7, wherein the second gear is a plastic gear.
The central drive device according to claim 7, characterized in that a sleeve (12) is fixed on the inner circumference of the second gear (14), and the sleeve (12) is connected to the second gear (14). ) Compression fit or integral molding, the sleeve (12) is fixed to the gear shaft (13).
A bicycle comprising a central drive device, characterized in that the central drive device is the central drive device according to any one of claims 1-9.