CN213705692U - Rear wheel power output mechanism for electric power-assisted bicycle - Google Patents

Abstract

The utility model discloses a rear wheel power take-off mechanism for electric power assisted bicycle, it contains a shell, a motor, a speed reduction unit and a positioning unit, a first mandrel and a second mandrel are rotationally located to the shell cover, the motor is located in the shell and has a stator of connecting first mandrel, speed reduction unit has a gear fixing frame, the stator of gear fixing frame rigid coupling motor and connection second mandrel, positioning unit has a bearing holder who sets firmly the shell and a bearing of locating between bearing holder and the second mandrel, and set up a fastener that supports the bearing in the outer peripheral face of second mandrel. Borrow this, can hit the bearing through the fastener when the second dabber receives axial force effect, then let the bearing hit the gear mount again, so can prevent that the second dabber from producing axial displacement.

Description

Rear wheel power output mechanism for electric power-assisted bicycle

Technical Field

The present disclosure relates to an electric power assisted bicycle, and more particularly, to a rear wheel power output mechanism for an electric power assisted bicycle.

Background

The traditional electric power-assisted bicycle obtains forward power by the pedaling force of a rider and the power provided by a power output mechanism (such as a hub motor), so that the electric power-assisted bicycle cannot cause too large burden on the physical strength of the rider, and can achieve the effect of body building in the rest of leisure.

In the conventional structure, the spindle and the planet carrier are originally made of a metal material (e.g., aluminum) and are integrally formed, and then the spindle and the planet carrier are changed into a two-piece structure and assembled in an interference fit manner, so as to achieve the effect of light weight. However, during operation, the spindle may move axially due to external force, and in order to limit the axial movement of the spindle, patent documents EP 2650204B 1 and CN 100540350C disclose a technique of locking one end of the spindle with a nut, which prevents the spindle from moving axially due to a stopping effect provided by the nut. However, in addition to increasing the volume of the overall structure in the radial direction, the end of the spindle for assembling the nut needs to be sleeved with a sleeve for assembling with the toothed disc, so the length of the spindle is too long under the influence of the nut, and the arrangement of other components is affected.

SUMMERY OF THE UTILITY MODEL

The present disclosure is directed to a rear wheel power output mechanism for an electric bicycle, which can effectively prevent an axle from moving axially.

To achieve the above object, the rear wheel power output mechanism of the present disclosure includes a housing, a motor, a first spindle, a speed reduction unit, a second spindle, and a positioning unit. The motor is arranged in the shell and is provided with a stator and a rotor which can rotate relative to the stator; the first mandrel is arranged at one end of the shell and allows the shell to rotate relative to the shell, and one end of the first mandrel is fixedly connected with the stator of the motor; the speed reducing unit is arranged in the shell and is provided with a gear shaft, a gear fixing frame, a plurality of speed reducing gears and a ring gear, the gear shaft is fixedly connected with a rotor of the motor, the gear fixing frame is connected with a stator of the motor, the plurality of speed reducing gears are arranged on the gear fixing frame and are meshed with the gear shaft, and the ring gear is fixedly arranged on the shell and is meshed with the plurality of speed reducing gears; the second mandrel is arranged at the other end of the shell and allows the shell to rotate relative to the shell, and one end of the second mandrel is fixedly connected with the gear fixing frame; the positioning unit is provided with a bearing retainer, a bearing and a fastener, the bearing retainer is fixedly arranged on the shell, the bearing is arranged between the bearing retainer and the mandrel and is close to one side of the gear fixing frame, and the fastener is arranged on the peripheral surface of the second mandrel and is abutted against the bearing.

Therefore, when the second spindle is subjected to the axial force, the bearing is collided by the fastener, and then the bearing is collided with the gear fixing frame, so that the stopping effect can be provided for the second spindle, and the second spindle is further prevented from axially moving.

Preferably, the outer peripheral surface of the second mandrel has a ring groove for disposing the fastener.

Preferably, the housing has a housing and an end cover, the housing is penetrated by the first spindle, the end cover is disposed at an opening of one end of the housing and penetrated by the second spindle, and the ring gear and the bearing retainer are both fixedly disposed on the end cover.

Preferably, each of the reduction gears has a large gear and a small gear coaxially connected to the large gear, the pinion shaft engages with the large gear of the plurality of reduction gears, and the ring gear engages with the small gear of the plurality of reduction gears. Through the two-stage design, in addition two can choose different materials to match to reach the effect that promotes the incorruptibility and noise reduction.

Drawings

Fig. 1 is a perspective view of a rear wheel power take-off mechanism of the present disclosure.

Fig. 2 is a partial exploded perspective view of the rear wheel power take off mechanism of the present disclosure.

Fig. 3 is a cross-sectional view of the rear wheel power take-off mechanism of the present disclosure.

Fig. 4 is an enlarged view of a portion a in fig. 3.

Description of reference numerals:

10-rear wheel power output mechanism

20-outer cover

22-shell

24-end cap

26-containing space

30-motor

32-rotor

34-stator

36-first mandrel

40-reduction unit

42-gear shaft

44-flat bond

46-gear fixing frame

48-first frame body

50-second frame body

52-ring gear

54-Pin part

56-reduction gear

58-big gear

60-pinion

62-second mandrel

64-ring groove

66-sleeve

70-positioning unit

72-bearing cage

74-bearing

76-fastener

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings.

The detailed construction, features, assembly or use of the rear wheel power output mechanism for an electric bicycle provided by the present disclosure will be described in the detailed description of the embodiments that follow. However, those of ordinary skill in the art should understand that the detailed description and specific examples, while indicating the specific embodiments of the disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.

Applicants first describe herein, throughout the specification and claims that follow, the directional terms used in the description and claims are used as reference to directions in the drawings. Next, in the embodiments and drawings to be described below, the same reference numerals are used to designate the same or similar components or structural features thereof.

With continued reference to fig. 1-3, the rear wheel power output mechanism 10 of the present disclosure includes a housing 20, a motor 30, a first spindle 36, a reduction unit 40, a second spindle 62, and a positioning unit 70.

The housing 20 includes a casing 22 and an end cap 24, the end cap 24 is disposed at an end of the casing 22 and forms a receiving space 26 for receiving most of the above components with the casing 22.

The motor 30 is disposed within the housing 20 and has a stator 34 and a rotor 32 rotatable relative to the stator 34. The rotor 32 is rotated to output an electric assist force by electric power supplied from a power supply source (e.g., a battery mounted to the vehicle frame, not shown).

A first spindle 36 is provided at one end of the housing 20 and allows the housing 20 to rotate relative thereto. One end of the first spindle 36 protrudes from the housing 20 to be assembled and fixed with a rear fork (not shown), and the other end of the first spindle 36 is connected to the stator 34 of the motor 30, so that the first spindle 36 is kept stationary.

The speed reduction unit 40 is used to reduce the speed of the electric power generated by the rotor 32 and then transmit the electric power. As shown in fig. 2 and 3, the speed reduction unit 40 is disposed in the housing 20 and has a gear shaft 42, a gear fixing frame 46, a ring gear 52 and a plurality of speed reduction gears 56 (three are taken as an example here), wherein: the pinion 42 is fixed to the rotor 32 of the motor 30 by a flat key 44, so that the pinion 42 is driven by the rotor 32 to rotate together; the gear fixing frame 46 is sleeved on the gear shaft 42 and has a first frame body 48 and a second frame body 50 connected to the first frame body 48, and the gear fixing frame 46 is connected with the stator 34 of the motor 30 through the first frame body 48 so that the gear fixing frame 46 is kept still; the outer circumferential surface of the ring gear 52 is fixedly arranged on the inner circumferential surface of the end cover 24 by a plurality of pin pieces 54, so that the ring gear 52 can rotate along with the shell 20; the plurality of reduction gears 56 are disposed between the first and second frame members 48, 50 of the gear fixing frame 46 and respectively have a large gear 58 and a small gear 60 coaxially connected to the large gear 58, and each reduction gear 56 engages with the gear shaft 42 via the large gear 58 and then engages with the ring gear 52 via the small gear 60, such that each reduction gear 56 rotates in situ relative to the gear fixing frame 46 on one hand and drives the ring gear 52 to rotate together with the housing 20 on the other hand. Through the two-step design, different materials are further used (for example, the large gear 58 is made of composite material, and the small gear 60 is made of metal), so that the effects of improving the durability and reducing the noise of each reduction gear 56 in the process of transmitting the electric power can be achieved at the same time.

A second spindle 62 is provided at the other end of the housing 20 and allows the housing 20 to rotate relative thereto. One end of the second spindle 62 protrudes from the housing 20, and is used for being assembled and fixed with a rear fork (not shown), and is also sleeved with a sleeve 66 for being assembled with a big fluted disc (not shown). The other end of the second spindle 62 is assembled to the gear holder 46 in a tight-fitting manner, so that the second spindle 62 remains stationary.

The positioning unit 70 has a bearing holder 72, a bearing 74 and a fastener 76. As shown in fig. 3 and 4, the bearing holder 72 is fixedly disposed on a side surface of the end cover 24 facing the gear fixing frame 46; the bearing 74 is arranged between the bearing retainer 72 and the second mandrel 62 and is close to one side surface of the gear fixing frame 46; the fastener is embedded in a ring groove 64 on the outer peripheral surface of the second mandrel 62 and abuts against the bearing 74.

As can be seen from the above, the rear wheel power output mechanism 10 of the present disclosure may hit the bearing 74 through the fastener 76 when the second spindle 62 is subjected to the axial force, and then the bearing 74 hits the gear fixing frame 46, so as to provide a blocking effect for the second spindle 62, so that the second spindle 62 is effectively prevented from generating the axial movement without increasing the length of the second spindle 62.

The above-mentioned embodiments, further detailed description of the objects, technical solutions and advantages of the present invention, it should be understood that the above-mentioned embodiments are only specific embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims (4)

1. A rear wheel power take-off mechanism for an electric power assisted bicycle, comprising:

a housing;

a motor, which is arranged in the shell and is provided with a stator and a rotor which can rotate relative to the stator;

a first spindle, which is arranged at one end of the shell and allows the shell to rotate relative to the shell, and one end of the first spindle is fixedly connected with the stator of the motor;

the speed reduction unit is arranged in the shell and is provided with a gear shaft, a gear fixing frame, a plurality of speed reduction gears and a ring gear, the gear shaft is fixedly connected with a rotor of the motor, the gear fixing frame is connected with a stator of the motor, the plurality of speed reduction gears are arranged on the gear fixing frame and are meshed with the gear shaft, and the ring gear is fixedly arranged on the shell and is meshed with the plurality of speed reduction gears;

the second mandrel is arranged at the other end of the shell and allows the shell to rotate relative to the shell, and one end of the second mandrel is fixedly connected with the gear fixing frame; and

and the positioning unit is provided with a bearing retainer, a bearing and a fastener, the bearing retainer is fixedly arranged on the shell, the bearing is arranged between the bearing retainer and the second mandrel and is close to one side of the gear fixing frame, and the fastener is arranged on the peripheral surface of the second mandrel and is abutted against the bearing.

2. The power take-off mechanism for a rear wheel of an electrically assisted bicycle as claimed in claim 1, wherein the spindle has a ring groove on its outer peripheral surface, and the fastener is disposed in the ring groove.

3. The rear wheel power output mechanism for an electric power-assisted bicycle of claim 1, wherein the housing has a housing body and an end cap, the housing body is penetrated by the first spindle, the end cap is arranged at an end opening of the housing body and is penetrated by the second spindle; the ring gear and the bearing retainer are fixedly arranged on the end cover.

4. The rear wheel power take-off mechanism for an electric power-assisted bicycle according to claim 1, wherein each of the reduction gears has a large gear and a small gear coaxially connected to the large gear, a plurality of the large gears engage with the pinion, and a plurality of the small gears engage with the ring gear.

Images