TWM604726U - High torque hub motor system and power assisted bicycle - Google Patents

Abstract

Provided is a high torque hub motor system, including a hub with a motor assembly and a harmonic drive disposed therein, and a main shaft with an input assembly provided on one end thereof. The input assembly is connected to and drives the hub. The motor assembly includes a stator and an inner rotor rotatably coupled to the main shaft. A circular spline is mounted on an inner wall of the hub. The system further includes a supporting drum connected to a flexspline and rotatably coupled to the main shaft. A one-way clutch is provided between the supporting drum and the main shaft. Due to the harmonic drive disposed in the hub motor, a transmission ratio of 1/50 or lower is achieved, facilitating the provision of an output torque of 80 N-m. With greater torque provided for various biking environments, biking experience can be improved.

Description

High-torque wheel hub motor drive system and assisted bicycle

This creation relates to power-assisted bicycles, in particular to a high-torque hub motor drive system and power-assisted bicycles.

Power-assisted bicycles have the advantages of labor-saving, large load, and fast speed, and soon have become the main means of people's short-distance travel and transportation.

Generally speaking, the inner space of the hub motor of the existing power-assisted bicycle is narrow, and the planetary reduction gear system is usually used to limit the transmission ratio to a small value range, so that the output power and torque of the hub motor are small, and it is difficult to meet the high resistance road surface. The riding needs. Therefore, the existing assisted bicycles provide limited assistance to riders. On the other hand, increasing the output torque of the in-wheel motor also needs to increase the output power, resulting in more serious heating of the in-wheel motor and reducing its service life.

In order to overcome the shortcomings of the prior art, the purpose of this creation is to provide a high-torque high-torque hub motor transmission system and a booster bicycle.

This creation provides a high-torque hub motor drive system, which includes a hub with a motor assembly and a harmonic drive reducer inside, and a main shaft with an input assembly at one end. The input component is connected with the hub and drives the hub. Harmonic drive reducer includes wave generator, flexible gear, flexible bearing and Rigid gears. The motor assembly includes an inner rotor connected to the main shaft in a rotatable manner. The inner rotor is connected to the wave generator and drives the wave generator. The wave generator is connected to the main shaft in a rotatable manner. The rigid gear is installed and fixed on the inner wall of the hub. The high-torque wheel hub motor transmission system of this creative embodiment further includes a support cylinder, which is connected to the flexible gear and drives the flexible gear. The support cylinder is connected with the main shaft in a rotatable manner. A one-way clutch is arranged between the support cylinder and the main shaft or between the inner rotor and the wave generator.

In an embodiment, the hub includes a hub cover and a housing, and the motor assembly includes a first end cover and a second end cover. The first end cover is rotatably connected with the hub cover. The shape of the outer surface of the first end cover is adapted to the shape of the inner surface of the hub cover and is separated by a predetermined distance.

In one embodiment, a thermal grease is filled between the hub cover and the first end cover, and the outer surface of the hub cover is provided with heat dissipation fins.

In an embodiment, the motor assembly includes a stator. The stator is fixed between the first end cover and the second end cover, and the stator and the inner wall of the hub are separated by a predetermined distance. The inner wall of the shell is provided with an oil trap.

In one embodiment, the one-way clutch is fixedly connected to the main shaft by a fixed key.

In one embodiment, the input assembly includes a ring gear base rotatably connected to the main shaft.

In one embodiment, a bush is fixedly provided on the hub, and the hub is rotatably connected with the main shaft through the bush.

In an embodiment, a ratchet wheel and a pawl are respectively provided on the gear plate tower base and the bush.

In the high-torque hub motor transmission system provided by this creative embodiment, when the human power drives the hub to rotate, the motor assembly is also activated to drive the wave generator to rotate, and the flexible gear is driven by the flexible bearing to oppose the rigid gear connected to the hub Rotation, which is driven by a motor to assist human pedaling And push the wheel hub to rotate. A one-way clutch is arranged between the support cylinder and the main shaft to avoid the reverse torque generated by the flexible bearing when the inner ring rotates when the motor is moving. In addition, when the motor assembly is disabled and pure human pedaling is used, or when the bicycle is sliding, the rotation of the hub also causes the rigid gear to rotate synchronously. At this time, the flexible gear rotates under force so that the flexible gear rotates around the main shaft when the one-way clutch is disconnected, and the synchronous rotation of the wave generator drives the inner rotor to rotate. This configuration has the least resistance to the inner rotor as a whole. The one-way clutch is used to avoid the fact that the wave generator and the rigid gear keep a high transmission ratio when they are stepped on by humans, which causes excessive motor resistance and slows down the bicycle sliding. The high-torque in-wheel motor transmission system of this invention is equipped with a harmonic drive reducer in the transmission in-wheel motor, so that the transmission ratio can reach more than 1/50, and thus the output torque of the high-torque in-wheel motor transmission system of this creative embodiment can be Reach 80 Newton meters. Therefore, in the riding process of the user, a greater output torque is provided to assist the user in riding, so as to adapt to more riding environments, thereby improving the riding experience of the user.

This creation provides a power-assisted bicycle, which includes a frame and the above-mentioned high-torque hub motor drive system installed on the frame.

In the assisted bicycle provided by this creation, its transmission ratio can reach more than 1/50, so that its output torque can reach 80 Nm, which can provide a greater output torque to assist the user during riding to adapt to greater resistance The road surface and the complex riding environment will improve the user’s riding experience.

1: Wheel hub

1a: Hub cover

1b: shell

1c: cooling fins

2: Spindle

3: input component

3a: Sprocket body

3b: Bushing

3c: ratchet

3d: pawl

4: Motor components

4a: stator

4b: inner rotor

4c: first end cap

4d: second end cap

4e: winding

4f: Magnet

5: Harmonic drive reducer

5a: Wave generator

5b: Flexible gear

5c: Flexible bearing

5d: rigid gear

6: Support tube

7: One-way clutch

7a: Fixed key

8: Thermal grease

9: Oil trap

10: Power-assisted bicycle

11: Frame

12: Variable speed chainring

13: The first bearing

14: The second bearing

15: The third bearing

16: The fourth bearing

Fig. 1 is a schematic structural diagram of a high-torque in-wheel motor transmission system according to a creative embodiment; Fig. 2 is a schematic structural diagram of a power-assisted bicycle according to the creative embodiment.

The creation will be further described in detail below in conjunction with the embodiments and the accompanying drawings.

Hereinafter, a high-torque in-wheel motor drive system and a power-assisted bicycle will be described with reference to FIGS. 1 to 2. The assisted bicycle 10 includes a frame 11 and a high-torque in-wheel motor drive system installed on the frame 11. 1 and 2, the high-torque hub motor transmission system includes a hub 1 and a main shaft 2. The two ends of the main shaft 2 respectively extend outside the hub 1. The hub 1 includes a hub cover 1a and a housing 1b. One end of the main shaft 2 (Figure One end of the main shaft 2 on the right side in 1) is installed and connected with an input assembly 3, which is connected to the hub 1 and drives the hub 1. A motor assembly 4 and a harmonic drive reducer 5 are arranged in the hub 1. The harmonic drive reducer 5 includes a wave generator 5a, a flexible gear 5b, a flexible bearing 5c, and a rigid gear 5d. The motor assembly 4 includes a stator 4 a and an inner rotor 4 b connected to the main shaft 2 in a rotatable manner relative to the main shaft 2. The inner rotor 4b is connected to the wave generator 5a and drives the wave generator 5a, and the wave generator 5a is connected to the main shaft 2 in a rotatable manner. The rigid gear 5d is installed and connected to the inner wall of the housing 1b of the hub 1. The high-torque motor transmission system of this creative embodiment further includes a support cylinder 6. The support cylinder 6 is connected with the flexible gear 5b, the support cylinder 6 is connected with the main shaft 2 in a rotatable manner, and a one-way clutch 7 is provided between the support cylinder 6 and the main shaft 2.

Specifically, the one-way clutch 7 is fixedly connected to the main shaft 2 by a fixed key 7a. In addition, the motor assembly 4 further includes a first end cover 4c, a second end cover 4d, a magnet 4f, and a winding 4e provided on the stator 4a. The wave generator 5a and the inner rotor 4b are rotatably connected to the main shaft 2 via the first bearing 13 respectively. The basic structure and principle of the motor assembly 4 in this creation are the same as that of the existing motor, and the basic structure and principle of the harmonic drive reducer 5 and the existing harmonic drive reducer 5 are the same, so neither will be elaborated too much.

During the riding of the assisted bicycle 10 of this creative embodiment, the cyclist steps on the driving input assembly 3 to drive the wheel hub 1 to rotate. On the other hand, the motor assembly 4 is activated to drive the wave generator 5a to rotate, and the flexible gear 5b and the rigid gear 5d are driven to rotate relative to each other via the flexible bearing 5c. Since the rigid gear 5d is fixedly connected to the hub 1, it is driven by the motor. Assist the manpower to step on and push the wheel hub 1 to rotate. A one-way clutch 7 is provided between the support cylinder 6 and the main shaft 2 to avoid the reverse torque generated by the flexible bearing 5c when the inner ring rotates when the motor is moving. In addition, when the motor is deactivated When the component 4 is pedaled by pure human power, or when the assisted bicycle 10 is sliding, the wheel hub 1 rotates while simultaneously rotating the rigid gear 5d. At this time, the flexible gear 5b is forced to rotate so that the flexible gear 5b rotates around the main shaft 2 when the one-way clutch 7 is disengaged, and the synchronous rotation of the wave generator 5a drives the inner rotor 4b to rotate. This configuration as a whole has the least resistance affecting the inner rotor 4b. The one-way clutch 7 is used to prevent the wave generator 5a and the rigid gear 5d from being stepped on by a human force. The rotation of the wave generator 5a and the rigid gear 5d maintains a high transmission ratio, which results in excessive motor resistance and slows the assisted bicycle 10 from sliding. The high-torque hub motor transmission system of this creative embodiment is equipped with a harmonic drive reducer 5 in the drive hub motor, so that its transmission ratio can reach 1/50 or more, and under this transmission ratio, it promotes the high torque of this creative embodiment The output torque of the in-wheel motor drive system can reach 80 Newton meters. Therefore, a greater output torque can be provided to assist the user in riding during the user's riding, so as to adapt to the road surface with greater resistance and the complex riding environment, thereby enhancing the user's riding experience.

Wherein, in other embodiments, the one-way clutch 7 may also be arranged between the inner rotor 4b and the wave generator 5a.

In the embodiment of the present creation, referring to FIG. 1, the first end cover 4c is sleeved on the main shaft 2 and is rotatably connected with the hub cover 1a via the second bearing 14. The shape of the outer surface of the first end cover 4c matches the shape of the inner surface of the hub cover 1a and is separated by a predetermined distance. A thermal grease 8 is filled between the hub cover 1a and the first end cover 4c. The stator 4a is fixed between the first end cover 4c and the second end cover 4d, and the stator 4a is separated from the inner wall of the hub 1 by a predetermined distance. The inner wall of the shell 1b near one end of the hub cover 1a is provided with an oil trap tube 9. During the working process, the inner rotor 4b and the hub 1 rotate, and the heat generated by the winding 4e of the motor can be dissipated through the thermal grease 8 and through the hub cover 1a. In addition, the outer surface of the hub cover 1a is provided with protruding heat dissipation fins 1c. The heat dissipation fins 1c are fin-shaped protrusions arranged on the surface of the hub cover at intervals, which increase the contact area between the hub cover 1a and the air. The heat dissipation effect of the in-wheel motor and prolong the service life of the in-wheel motor.

In this creative embodiment, referring to FIG. 1, the input assembly 3 includes a ring gear base 3 a that is rotatably connected to the main shaft 2. The hub 1 is fixedly provided with a bushing 3b, and the bushing 3b and the main A third bearing 15 is provided between the shaft 2. The hub 1 is rotatably connected to the main shaft 2 via a bush 3b. The bushing 3b and the ring gear base 3a are respectively provided with a corresponding ratchet wheel 3c and a pawl 3d, so that the assisted bicycle 10 does not drag the pedal to rotate when sliding.

In addition, the ring gear base 3a is rotatably connected to the main shaft 2 via a fourth bearing 16. The gear wheel base 3a can be provided with a 3 to 11 speed gear wheel 12, which is convenient for the user to select the pedaling speed and the vehicle speed in a larger range.

The above is an explanation of the high-torque hub motor drive system and assisted bicycles of this creation, which are used to help understand this creation, but the implementation of this creation is not limited by the above-mentioned embodiments, and anything made without departing from the principle of this creation The changes, modifications, substitutions, combinations, and simplifications should be regarded as equivalent replacement methods, and they are all included in the protection scope of this creation.

1: Wheel hub

1a: Hub cover

1b: shell

1c: cooling fins

2: Spindle

3: input component

3a: Sprocket body

3b: Bushing

3c: ratchet

3d: pawl

4: Motor components

4a: stator

4b: inner rotor

4c: first end cap

4d: second end cap

4e: winding

4f: Magnet

5: Harmonic drive reducer

5a: Wave generator

5b: Flexible gear

5c: Flexible bearing

5d: rigid gear

6: Support tube

7: One-way clutch

7a: Fixed key

8: Thermal grease

9: Oil trap

13: The first bearing

14: The second bearing

15: The third bearing

16: The fourth bearing

Claims (9)

A high-torque wheel hub motor transmission system includes: a hub with a motor assembly and a harmonic drive reducer; and a main shaft, one end of the main shaft is provided with an input assembly, the input assembly is connected to the hub and drives the hub , Wherein the harmonic drive reducer includes a wave generator, a flexible gear, a flexible bearing, and a rigid gear. The motor assembly includes an inner rotor rotatably connected to the main shaft, and the inner rotor is connected to the wave generator and drives The wave generator, the wave generator is rotatably connected to the main shaft, and the rigid gear is mounted and fixed on the inner wall of the hub; wherein the high-torque hub motor transmission system further includes a support tube, the support tube and the A flexible gear connects and drives the flexible gear, the support cylinder is connected with the main shaft in a rotatable manner, and a one-way clutch is arranged between the support cylinder and the main shaft or between the inner rotor and the wave generator. For example, the high-torque hub motor transmission system of claim 1, wherein the hub includes a hub cover and a housing, the motor assembly includes a first end cover and a second end cover, and the first end cover is rotatably connected to the hub cover , The shape of the outer surface of the first end cover matches the shape of the inner surface of the hub cover and is separated by a predetermined distance. For example, the high-torque hub motor transmission system of claim 2, wherein the heat-conducting grease is filled between the hub cover and the first end cover, and the outer surface of the hub cover is provided with heat dissipation fins. For example, the high-torque hub motor transmission system of claim 3, wherein the motor assembly includes a stator, the stator is fixed between the first end cover and the second end cover, and the stator is separated from the inner wall of the hub by a predetermined distance, And the inner wall of the shell is provided with an oil trap. Such as the high-torque hub motor transmission system of claim 1, wherein the one-way clutch is fixedly connected to the main shaft by a fixed key. Such as the high-torque hub motor transmission system of claim 1, wherein the input assembly includes a ring gear base rotatably connected to the main shaft. For example, the high-torque hub motor transmission system of claim 6, wherein a bush is fixedly provided on the hub, and the hub is rotatably connected with the main shaft through the bush. For example, the high-torque hub motor transmission system of claim 7, wherein the gear plate tower base and the bush are respectively provided with a matching ratchet wheel and pawl. A power-assisted bicycle includes: a frame; and the high-torque in-wheel motor drive system according to any one of claims 1 to 8, which is installed to the frame.

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