TW202400463A - Power module of electric assisted bicycle - Google Patents

Abstract

The present invention provides a power module of an electric assisted bicycle including a pedal shaft, a gear-plate-output shaft, a reducer, a motor, a first sensor, a housing, a second sensor, and a driving controller. The gear-plate-output shaft, the reducer-output shaft, and the reducer-fixed shaft are arranged in parallel with the pedal shaft along the axial direction, and sleeved on the pedal shaft concentrically. The motor drives the reducer through the reducer-input shaft to drive the gear-plate-output shaft to rotate. The first sensor is arranged on the reducer-fixed shaft for detecting a first torque of the reducer-output shaft acting on the reducer-fixed shaft. The reducer-fixed shaft is connected to the housing. A frame-fastening component protrudes outwardly from the housing, and is configured to fix the power module on the frame. The second sensor is arranged on the frame-fastening component for detecting a second torque acting on the frame by the power module. The driving controller uses the first torque and the second torque to control the motor.

Description

Power module for electric power-assisted bicycle

This case is about a power module, specifically a power module for a coaxially configured mid-mounted electric power-assisted bicycle. Two sensors are installed separately to improve the overall output of the power module without increasing the overall size and space. Precision enables optimal control of motor auxiliary force.

Electric assisted bicycle, also known as e-Bike, is a bicycle with an integrated motor and reducer to provide motor power for auxiliary propulsion. There are many types of electric bicycles on the market, but they are usually divided into two broad categories: electric-assisted bicycles that detect and assist the rider's pedaling force and general electric bicycles that are driven only by an electric motor. Since electric power-assisted bicycles must integrate human power and motor auxiliary power at the same time, and meet the demand for the coexistence of dual power (human power and motor auxiliary power), so as to optimize the performance of the power module in different usage scenarios, the sensing of force is Accuracy is more demanding.

The power module of traditional electric power-assisted bicycles uses the human input of the pedal shaft to control the input of motor assist force, so the torque sensor needs to be placed on the middle pedal shaft. However, because the diameter of the middle pedal shaft is too small, it is difficult to add a torque sensor, and the torque sensor combined with a traditional power module has poor accuracy and high cost. Furthermore, the pedal shaft combined with the torque sensor already has a rather complex surface structure, which is not conducive to the concentric fit of the output shaft of the motor auxiliary force. Therefore, the output shaft of the motor auxiliary force and the pedal shaft can only adopt a separate shaft design. , making it difficult to reduce the size of the power module.

On the other hand, after traditional electric power-assisted bicycles control the input of motor assist force, they only use the rotation speed to monitor the effectiveness of the overall power output (human power combined with motor assist force). They do not monitor the output of motor assist force separately, so they cannot be grasped in real time. Actual output of motor auxiliary force. Since the pedaling shaft combined with the torque sensor is no longer conducive to the concentric integration of the motor's assist force, if another torque sensor is added to monitor the actual output of the motor's assist force, the overall dimensions will need to be increased to separately measure the human assist force. The pedal output and motor assist output make the design of the power module more complicated.

In view of this, it is necessary to provide a power module for an electric power-assisted bicycle that can combine the torque sensor with a simple method to simultaneously measure the pedal output of the person and the auxiliary output of the motor without increasing the external dimensions and space. The human pedal output and motor auxiliary output perform a torque feedback to improve the accuracy of the overall output of the power module and achieve optimal control of the motor auxiliary force to solve the deficiencies of conventional technology.

The purpose of this case is to provide a power module for an electric power-assisted bicycle that uses a simple method to combine a torque sensor with a torque sensor to simultaneously measure the pedal output of a person and the auxiliary output of the motor without increasing the external dimensions and space. The pedaling force and motor auxiliary output perform torque feedback to improve the overall output accuracy of the power module and achieve optimal control of the motor auxiliary force.

Another purpose of this case is to provide a power module for an electric power-assisted bicycle. By arranging the first sensor and the second sensor on the fixed shaft of the reducer and the housing of the power module respectively, the drive controller can control the first torque and the second torque measured by the first sensor. The second torque measured by the sensor is used to control the motor. When the rider is not pedaling, neither the first sensor nor the second sensor will generate any signal. By comparing the difference between the second torque and the first torque with a predetermined value, the drive controller can control the timing and scope of the motor's starting auxiliary force, and at the same time perform torque feedback of the motor's auxiliary output to improve the overall output accuracy of the power module. , so that the motor auxiliary force can be optimally controlled.

In order to achieve the aforementioned purpose, this case provides a power module for an electric power-assisted bicycle, including a pedal shaft, a gear plate output shaft, a reducer, a motor, a first sensor, a housing, a second sensor, and a drive controller. The pedal shaft is arranged along the axial direction. The gear plate output shaft is arranged parallel to the pedal shaft in the axial direction, and is concentrically sleeved on the pedal shaft in the radial direction. The reducer has a reducer output shaft and a reducer fixed shaft respectively arranged in parallel with the pedal shaft in the axial direction, and the reducer output shaft is concentrically sleeved on the gear plate output shaft along the radial direction. The motor is mechanically connected to the reducer and drives the reducer through the reducer input shaft. The first sensor is disposed on the fixed shaft of the reducer to detect the first torque exerted by the output shaft of the reducer on the fixed shaft of the reducer. The shell includes frame fixings and accommodating space. The accommodating space is configured to accommodate a pedal shaft, a gear plate output shaft, a reducer and a motor. The two ends of the pedal shaft pass through the shell respectively, and the reducer is connected to the fixed shaft. To the casing, the frame fixing piece protrudes outward from the casing to fix the power module on the frame. The second sensor is disposed on the frame fixing member to detect the second torque exerted by the power module on the frame, wherein the drive controller is electrically connected to the motor, the first sensor and the second sensor, And the motor is controlled based on the difference between the first torque and the second torque.

In one embodiment, when the difference between the second torque and the first torque is greater than or equal to a predetermined value, the drive controller starts the motor to output the motor output torque. In one embodiment, when the difference between the second torque and the first torque is less than a predetermined value, the drive controller turns off the motor.

In one embodiment, the first torque is a reducer output torque acting on the diameter of the fixed shaft of the reducer in a tangential direction perpendicular to the axial direction.

In one embodiment, the second torque includes the output torque of the reducer and the output torque of a human pedal, wherein the output torque of the human pedal acts on the casing in a tangential direction perpendicular to the axial direction.

In one embodiment, the gear plate output shaft is radially and concentrically sleeved on the pedal shaft through a first one-way bearing. When the pedal shaft is rotated under force, the gear plate output shaft is driven to rotate by the first one-way bearing.

In one embodiment, the reducer output shaft is radially concentrically sleeved on the gear plate output shaft through a second one-way bearing. When the motor drives the reducer to rotate the reducer output shaft, the reducer output shaft passes through the second one-way bearing. The bearing drives the sprocket output shaft to rotate.

In one embodiment, the housing includes a front fixing plate and a rear fixing plate, which are respectively arranged on two opposite sides of the housing along the axial direction, wherein the pedal shaft penetrates the front fixing plate and the rear fixing plate along the axial direction.

In one embodiment, the fixed end of the fixed shaft of the reducer is connected to the rear fixed plate, and the fixed shaft of the reducer is concentrically fitted to the pedal shaft through the first two-way bearing.

In one embodiment, the torsional rigidity of the rear fixed plate is greater than the torsional rigidity of the fixed shaft of the reducer.

In one embodiment, the side edge of the sprocket output shaft is connected to the front fixed plate through the second two-way bearing, and the side edge is concentrically fitted to the pedal shaft through the third two-way bearing.

In one embodiment, the reducer further includes an output gear and a fixed gear, which are respectively disposed on the output shaft of the reducer and the fixed shaft of the reducer. The output gear and the fixed gear are docked with each other. When the output shaft of the reducer drives the gear plate to rotate out of the shaft, Transmit the first torque.

In the power module of the electric power-assisted bicycle provided by the present invention, the pedal shaft, the gear plate output shaft and the reducer output shaft are coaxially designed and housed in the housing of the power module. The first sensor and the second sensor The sensors are respectively installed on the fixed shaft of the reducer and the frame fixing part of the power module. Compared with the current mainstream, which sets the complicated torque sensor on the pedal shaft in the middle, and the pedal shaft is connected to the output shaft of the reducer. The parallel non-coaxial design reduces the difficulty of sensor installation, saves assembly space and reduces the overall size of the machine. Since the installation of the sensor does not affect the sensing area and assembly convenience due to the small diameter of the pedal shaft, the accuracy of the sensor can be improved, the cost can be reduced, and the space utilization can also be improved. In addition, different position sensors are configured to detect the output torque of the reducer and the output torque of the human pedal, which can be used to control the timing and scope of the motor's starting auxiliary force. At the same time, torque feedback of the motor's auxiliary output is performed to improve the overall output of the power module. Precision enables optimal control of motor auxiliary force.

Some typical embodiments embodying the features and advantages of this case will be described in detail in the following description. It should be understood that this case can have various changes in different aspects without departing from the scope of this case, and the descriptions and drawings are essentially for illustrative purposes and are not used to limit this case.

In this embodiment, the power module of the electric power-assisted bicycle (hereinafter referred to as the power module 1) is, for example, used in a mid-mounted structure. The power module 1 includes a pedal shaft 10, a gear plate output shaft 20, and a reduction gear. machine 30, a motor 40, a first sensor 50, a housing 60, a second sensor 70 and a drive controller 80. The aforementioned mid-mounted structure means that the power module 1 is installed between the front wheel and the rear wheel of the electric power-assisted bicycle, which is usually used to distinguish it from the hub-type structure that is directly installed on the wheel. The length direction of the pedal shaft 10 is arranged along the axial direction C. The axial direction C is, for example, parallel to the X-axis and perpendicular to the Y-axis and the Z-axis, where the direction of gravity is opposite to the Z-axis direction. The gear disc output shaft 20 is in the shape of a long tube and is arranged parallel to the pedal shaft 10 along the axial direction C. The inner surface of the gear disc output shaft 20 is concentrically sleeved in the radial direction through the first one-way bearing 81 . The radial direction of the outer surface of the pedal shaft 10 is perpendicular to the aforementioned axial direction C. In this embodiment, when the pedal shaft 10 receives the pedal force of the rider and rotates in the forward direction, the first one-way bearing 81 drives the gear plate output shaft 20 to rotate. In this embodiment, the reducer 30 has, for example, a reducer output shaft 31 , an output gear 32 , a reducer fixed shaft 33 , a fixed gear 34 and a reducer input shaft 35 . The reducer output shaft 31, the reducer fixed shaft 33 and the reducer input shaft 35 are respectively arranged parallel to the pedal shaft 10 along the axial direction C, and the pedal shaft 10 passes through the reducer output shaft 31, the reducer fixed shaft 33 and the reduction gear. The engine input shaft 35 forms a coaxial structure, and the reducer output shaft 31 is concentrically sleeved on the gear plate output shaft 20 along the radial direction, and is connected to the outer surface of the gear plate output shaft 20 through the second one-way bearing 82 . It should be noted that the first one-way bearing 81 is composed of a one-way clutch. Through the first one-way bearing 81, the pedal shaft 10 can only drive the gear plate output shaft 20 in a single rotation direction, that is, only pedaling in a single direction. The pedal force can be transmitted to drive the sprocket output shaft 20 to drive the vehicle forward. However, if the pedal is pedaled in the opposite direction, the sprocket output shaft 20 cannot be driven. In this embodiment, the motor 40 is mechanically connected to the reducer 30, wherein the motor output shaft 41 of the motor 40 is mechanically connected and drives the reducer 30 through the reducer input shaft 35, so that the reducer 30 rotates through the reducer output shaft 31 and passes through the first Two one-way bearings 82 drive the gear plate output shaft 20 to rotate. Similarly, the second one-way bearing 82 is a one-way clutch. Through the second one-way bearing 82, the reducer output shaft 31 can only drive the gear plate output shaft 20 in a single rotation direction, that is, it is decelerated when it only rotates in a single direction. Only then can the torque output of the machine be transmitted to drive the sprocket out of the shaft 20 and drive the vehicle forward. In other words, in this embodiment, the first one-way bearing 81 and the second one-way bearing 82 can enable the same single rotation direction, so that the human output of the pedal shaft 10 and the motor auxiliary force transmitted by the reducer output shaft 31 can affect the gear plate. The driving effects of the output shaft 20 can be input separately and added to each other. Of course, this case is not limited to this.

In this embodiment, the output gear 32 is provided on the output shaft 31 of the reducer, and the fixed gear 34 is provided on the fixed shaft 33 of the reducer. The output gear 32 and the fixed gear 34 are arranged along the axial direction C and butt with each other, so as to facilitate the movement of the reducer. When the output shaft 31 drives the gear plate output shaft 20 to rotate, it transmits a first torque _TA . The first sensor 50 is, for example, disposed on the outer ring wall 330 of the reducer fixed shaft 33 to detect the action of the reducer output shaft 31 on the reducer fixed shaft when the reducer output shaft 31 drives the gear plate output shaft 20 to rotate. The first torque T _A of the shaft 33.

In this embodiment, the housing 60 is in the shape of a sleeve and is arranged along the axial direction C, and includes a frame fixing member 61 and an accommodating space 62. The accommodating space 62 is configured to accommodate the pedal axle 10 and the gear plate. The output shaft 20 , the reducer 30 and the motor 40 , in which the two ends of the pedal shaft 10 respectively penetrate both sides of the housing 60 along the axial direction C, so that the two opposite ends of the pedal shaft 10 are exposed. The reducer fixed shaft 33 is accommodated in the accommodation space 62, and a fixed end 331 of the reducer fixed shaft 33 is connected to the housing 60. The frame fixing member 61 protrudes outward from the housing 60 and has a surface with the housing 60. The height difference is used to fix the power module 1 on a frame (not shown) in an assembled manner. In addition, in this embodiment, the second sensor 70 is, for example, disposed on the side wall 610 of the frame fixing member 61 to detect a second torque _TB exerted by the power module 1 on the frame. In this embodiment, the second torque _TB is greater than or equal to the first torque _TA . The first torque _TA and the second torque _TB are used to control the motor output torque of the motor 40 .

In this embodiment, the drive controller 80 is electrically connected to the motor 40 , the first sensor 50 and the second sensor 70 . In this embodiment, the first sensor 50 includes, for example, a strain gauge, which is disposed on the outer ring wall 330 of the fixed shaft 33 of the reducer along the axial direction C to sense, for example, a first value of the output torque of the reducer. Torque T _A , of which the first torque T _A acts on the outer diameter of the reducer fixed shaft 33 in a tangential direction perpendicular to the axial direction C. The tangential direction is, for example, parallel to the vehicle traveling direction, but this case is not limited thereto. this. In this embodiment, the second sensor 70 includes, for example, strain gauges 71 a and 71 b radially disposed on one side wall 610 of the frame fastener 61 and spaced apart from each other. The strain gauges 71a and 71b are used to sense a second torsion force _TB exerted by the power module 1 on the frame. The second torsion force _TB further acts on the tangent line perpendicular to the axial direction C on the frame fixing member 61. direction, for example, the tangent direction is parallel to the direction of traffic, but this case is not limited to this. In this embodiment, the drive controller 80 controls the motor 40 based on the difference between the second torque _TB and the first torque _TA . The operation process of power module 1 will be further explained later.

In this embodiment, the housing 60 is in the shape of a sleeve and is arranged along the axial direction C, and includes a front fixing plate 63 and a rear fixing plate 64, which are respectively arranged on two opposite sides of the housing 60 along the axial direction C to accommodate. The placement space 62 is defined between the front fixing plate 63 and the rear fixing plate 64 . The two opposite ends of the pedal shaft 10 respectively penetrate the front fixed plate 63 and the rear fixed plate 64 along the axial direction C. In this embodiment, the fixed end 331 of the reducer fixed shaft 33 is connected to the rear fixed plate 64 , and the fixed end 331 is concentrically fitted to the pedal shaft 10 through a first two-way bearing 83 . It should be noted that this case does not limit the combination of the front fixing plate 63 and the rear fixing plate 64 . In this embodiment, the frame fixing member 61 protrudes radially outward from the outer edge of the rear fixing plate 64 and extends out of the housing 60 . In other embodiments, the frame fixing member 61 may, for example, directly extend outward from the outer periphery of the housing 60 without protruding through the rear fixing plate 64 . This case is not limited to this. In this embodiment, the first sensor 50 is disposed on the reducer fixed shaft 33 , and the second sensor 70 is disposed on the frame firmware 61 on the outer edge of the rear fixing plate 64 . In response to the requirement that the second torque _TB measured by the second sensor 70 is greater than the first torque _TA measured by the first sensor 50 , the torsional rigidity of the rear fixed plate 64 is greater than the torsional rigidity of the reducer fixed shaft 33 . good. In addition, in this embodiment, one side edge 21 of the chainring output shaft 20 is connected to the front fixed plate 63 through a second two-way bearing 84, and the side edge 21 is concentrically fitted to the pedal shaft 10 through a third two-way bearing 85. superior.

In this embodiment, the power module 1 further includes a chain sprocket 90 , which is concentrically sleeved on the side edge 21 of the sprocket output shaft 20 in the radial direction and adjacent to the outer surface of the sprocket output shaft 20 . When the pedal shaft 10 is stepped on by human power and rotates the gear wheel output shaft 20 in the forward direction, a second torque _TB output is provided and transmitted to the rear wheel (not shown) through a chain of an electric power-assisted bicycle, for example, so that the electric power-assisted bicycle can move forward. It should be noted that the second torque _TB output of the chain gear shaft 20 or the chain gear 90 can be driven by the foot pedal shaft 10 through the first one-way bearing 81 to rotate the chain gear shaft 20 in the forward direction, for example, simply by human pedaling. To provide, or at the same time, the motor output shaft 41 of the motor 40 drives the reducer output shaft 31 to rotate, so that the reducer output shaft 31 drives the gear plate output shaft 20 to rotate in the forward direction through the second one-way bearing 82 and then provides motor auxiliary force. . In other words, when the motor auxiliary force does not act, the first torque _TA =0. At this time, the torque output of the chainring output shaft 20 is simply generated by the human pedaling force through the pedal shaft 10 through the first one-way bearing 81 . In the case of motor auxiliary force, the pedaling torque generated by the human pedaling force through the first one-way bearing 81 and the motor auxiliary force generated by the motor output shaft 41 and the reducer output shaft 31 through the second one-way bearing 82 , and at the same time, the torque output is provided and transmitted to the rear wheel through the chain, making the electric power-assisted bicycle move forward. At this time, the first torque T _A can be measured.

It should be noted that the sprocket output shaft 20 and the chain sprocket 90 in this case can be disposed close to the rider's right or left foot side, and the forward direction of the aforementioned forward rotation means that the sprocket output shaft 20 moves along a direction. The rotation direction drives the chain sprocket 90, the chain and the rear wheel to rotate in the direction of the pedal shaft 10 that makes the electric power-assisted bicycle move forward. This rotation direction will be due to the sprocket output shaft 20 and the chain sprocket 90 being arranged close to the rider. The right foot side or the left foot side, or two rotation directions, clockwise or counterclockwise, are defined when viewed from different sides. These rotation directions, combined with the configuration of the one-way bearings 81 and 82, can be used to determine whether the electric power-assisted bicycle is driven forward. , to avoid damage to the machine due to incorrect pedaling posture, and is not used to limit this case.

Refer to pictures 1 to 5. When the rider is not pedaling, neither the first sensor 50 nor the second sensor 70 senses any signal, and at this time, the first torque T _A and the second torque T _B are both zero. . When the rider starts to pedal, as in step S01, the second sensor 70 can sense the second torque T _B > 0, but the motor 40 is not started, so the first sensor 50 measures the first Torque T _A =0. In this embodiment, the drive controller 80 controls the opening and closing timing of the motor 40 and the amount of torque output when it is opened based on the difference between the second torque _TB and the first torque _TA . In one embodiment, the drive controller 80 may first set a predetermined value T _PRESET for determining the torque of the starting motor 40 . The initial values of the first torque T _A and the second torque T _B are both zero. When the rider starts to pedal, the second torque T _B begins to increase and is no longer zero. At this time, as in step S02, the drive controller 80 determines that although the difference between the second torque _TB and the first torque _TA is not zero, it is still less than the predetermined value T _PRESET , which is in the initial stage, so the drive controller 80 has not yet determined that it is necessary. The motor 40 is turned on to provide auxiliary force. In this embodiment, when the auxiliary output of the motor 40 of the power module 1 does not act, the reducer 30 will not be driven, the first sensor 50 will not generate a signal, and the strain gauges 71a and 71 of the second sensor 70 will not be driven. 71b corresponds to the measurement of the second torque T _B provided based on human pedaling, as shown in Figure 6 . Thereafter, in step S03, when the drive controller 80 determines that the difference between the second torque _TB and the first torque _TA is greater than or equal to the predetermined value T _PRESET , the drive controller 80 starts the motor 40 to cause the motor 40 to output The shaft 41 output motor outputs torque. In detail, the motor 40 drives the reducer 30 to rotate the reducer output shaft 31 and drive the gear plate output shaft 20 to rotate. At this time, the strain gauge of the first sensor 50 can correspondingly measure the first torque T _A >0 acting on the reducer fixed shaft 33 of the reducer output shaft 31, while the strain gauges 71a and 71a of the second sensor 70 71b can correspondingly measure the second torque T _B that the power module 1 acts on the frame, as shown in Figure 7. The second torque T _B is the total output torque including the output torque of the reducer (the first torque T _A ) and the output torque of the human pedal. The total output torque acts on the tangential direction of the housing 60 , that is, on the tangential direction of the housing 60 that is perpendicular to the axial direction C. This tangential direction is parallel to the vehicle traveling direction, for example, and is not used to limit this case. In addition, under the action of the dual summed output torque of the rider's pedal output and the motor's auxiliary output, the drive controller 80 controls the motor output torque of the motor 40 to output stably. At this time, the first sensor 50 measures the first The torque _TA maintains a constant value, that is, the motor 40 maintains a constant output. Once the rider reduces the pedal output, the second torque _TB measured by the second sensor 70 can be reduced. When the drive controller 80 determines that the difference between the second torque T _B and the first torque T _A is less than the predetermined value T _PRESET again, as shown in step S04 , the drive controller 80 determines that the motor 40 needs to be turned off to stop the output of the motor. Torque.

As shown in FIG. 8 , the second torque _TB output from the gear plate output shaft 20 or the chain gear plate 90 can be sensed to the strain gauges 71 a and 71 b of the second sensor 70 . When the motor auxiliary force acts, the output source of the second torque T _B includes the human pedal output torque and the reducer output torque. Since the first torque _TA measured by the first sensor 50 is equal to the output torque of the reducer, the output torque of the human pedal can be represented by the difference between the second torque _TB and the first torque _TA , that is, the output of the human pedal Torque = second torque T _B ─ first torque T _A .

To sum up, this project provides a power module for an electric power-assisted bicycle, which combines a torque sensor with a simple method to simultaneously measure the human pedal output and the motor auxiliary output without increasing the external dimensions and space. The pedal output and motor auxiliary output are used for torque feedback to improve the overall output accuracy of the power module and achieve optimal control of the motor auxiliary force. Furthermore, by arranging the first sensor and the second sensor respectively on the fixed shaft of the reducer and the frame fixing part of the power module, the drive controller can measure the first sensor according to the first sensor. A torque and a second torque measured by the second sensor are used to control the motor to output the motor output torque. When the rider is not pedaling, neither the first sensor nor the second sensor will generate any signal. When the rider starts pedaling, by comparing the difference between the second torque and the first torque with a predetermined torque value, the drive controller can control the timing and scope of the motor's auxiliary force, and at the same time perform the torque return of the motor's auxiliary force. It improves the overall output accuracy of the power module and achieves optimal control of the motor's auxiliary force.

This case may be modified in various ways by those who are familiar with this technology, but none of them will deviate from the intended protection within the scope of the patent application.

1: Power module 10: Pedal shaft 20: Gear plate output shaft 21: Side edge 30: Reducer 31: Reducer output shaft 32: Output gear 33: Reducer fixed shaft 330: Outer ring wall 331: Fixed end 34 : Fixed gear 35: Reducer input shaft 40: Motor 41: Motor output shaft 50: First sensor 60: Housing 61: Frame fixture 610: Side wall 62: Accommodation space 63: Front fixed plate 64: Rear Fixed plate 70: second sensors 71a, 71b: strain gauge 80: drive controller 81: first one-way bearing 82: second one-way bearing 83: first two-way bearing 84: second two-way bearing 85: third Two-way bearing 90: chain gear C: axial T _A : first torque T _B : second torque T _PRESET : predetermined value S01~S04: steps X, Y, Z: axis

Figure 1 is a structural diagram showing the appearance of the power module of the electric power-assisted bicycle according to the preferred embodiment of the present invention. Figure 2 is a cross-sectional view of the power module of the electric power-assisted bicycle according to the preferred embodiment of the present invention. Figure 3 is a schematic diagram showing the combination of the first sensor installed on the fixed shaft of the reducer in the preferred embodiment of the present invention. Figure 4 is a schematic diagram showing the location of each sensor in the power module of the electric power-assisted bicycle according to the preferred embodiment of the present invention and its corresponding measurement force. Figure 5 is a flow chart showing the operation of the power module of the electric power-assisted bicycle according to the preferred embodiment of the present invention. Figure 6 is a schematic diagram showing the force measured by the second sensor corresponding to the power module of the electric power-assisted bicycle according to the preferred embodiment of the present invention when the motor auxiliary output does not act. Figure 7 is a schematic diagram showing the corresponding measurement force of the second sensor and the first sensor when the power module of the electric power-assisted bicycle according to the preferred embodiment of the present invention acts on the auxiliary output of the motor. Figure 8 is a schematic diagram showing the corresponding relationship between the total output torque measured by the second sensor and the output torque of the human pedal in the power module of the electric power-assisted bicycle according to the preferred embodiment of the present invention.

1: Power module of electric power-assisted bicycle

10: Pedal shaft

20: The gear plate comes out of the shaft

21: Side edge

30:Reducer

31:Reducer output shaft

32:Output gear

33: Fixed shaft of reducer

331: Fixed end

34:Fixed gear

35:Reducer input shaft

40:Motor

41:Motor shaft output

50:First sensor

60: Shell

61: Frame fixings

610:Side wall

62: Accommodation space

63: Front fixed plate

64:Rear fixed plate

70: Second sensor

80: Drive controller

81:The first one-way bearing

82: Second one-way bearing

83:The first two-way bearing

84: Second two-way bearing

85:Third two-way bearing

90:Chain gear plate

C: Axial

X, Y, Z: axis

Claims (10)

A power module for an electric power-assisted bicycle, including: One pedal shaft is arranged along one axis; A toothed disc shaft is arranged parallel to the pedal shaft along the axial direction, and is concentrically sleeved on the pedal shaft along a radial direction; A reducer having a reducer output shaft and a reducer fixed shaft respectively arranged parallel to the pedal shaft along the axial direction, and the reducer output shaft is concentrically sleeved on the gear plate output shaft along the radial direction; A motor is mechanically connected to the reducer and drives the reducer through a reducer input shaft; A first sensor is disposed on the fixed shaft of the reducer to detect a first torque exerted by the output shaft of the reducer on the fixed shaft of the reducer; A housing includes a frame fixing member and an accommodating space. The accommodating space is configured to accommodate the pedal shaft, the gear plate output shaft, the reducer and the motor, wherein both ends of the pedal shaft Passing through the housing respectively, the reducer fixed shaft is connected to the housing, and the frame fixing piece protrudes outward from the housing to fix the power module on a vehicle frame; A second sensor is provided on the frame fixing member to detect a second torsion force exerted by the power module on the frame; and A drive controller is electrically connected to the motor, the first sensor and the second sensor, wherein the drive controller controls the motor based on the difference between the second torque and the first torque. The power module of an electric power-assisted bicycle as claimed in claim 1, wherein when the difference between the second torque and the first torque is greater than or equal to a predetermined value, the drive controller starts the motor to output a motor output torque; When the difference between the second torque and the first torque is less than the predetermined value, the drive controller turns off the motor. The power module of an electric power-assisted bicycle as claimed in claim 1, wherein the first torque is a reducer output torque acting on the diameter of the reducer fixed shaft in a tangential direction perpendicular to the axial direction. The power module of an electric power-assisted bicycle as claimed in claim 3, wherein the second torque includes the output torque of the reducer and a human pedal output torque, wherein the human pedal output torque acts on the housing and the shaft To the vertical tangent direction. The power module of an electric power-assisted bicycle as claimed in claim 1, wherein the gear plate output shaft is concentrically sleeved on the pedal shaft along the radial direction through a first one-way bearing, wherein the pedal shaft rotates under force The gear plate output shaft is driven to rotate through the first one-way bearing. The power module of an electric power-assisted bicycle as claimed in claim 5, wherein the reducer output shaft is concentrically sleeved on the gear plate output shaft along the radial direction through a second one-way bearing, and the motor drives the reducer. When the reducer output shaft is rotated, the reducer output shaft drives the gear plate output shaft to rotate through the second one-way bearing. The power module of an electric power-assisted bicycle as claimed in claim 1, wherein the housing includes a front fixing plate and a rear fixing plate, respectively disposed on two opposite sides of the housing along the axial direction, wherein the pedal shaft It penetrates the front fixing plate and the rear fixing plate along the axial direction. The power module of an electric power-assisted bicycle as described in claim 7, wherein a fixed end of the reducer fixed shaft is connected to the rear fixed plate, and the reducer fixed shaft is concentrically fitted to the foot through a first two-way bearing. The torsional rigidity of the rear fixed plate is greater than the torsional rigidity of the fixed shaft of the reducer. The power module of an electric power-assisted bicycle as claimed in claim 8, wherein one side edge of the gear plate output shaft is connected to the front fixed plate through a second two-way bearing, and the side edge is concentrically fitted through a third two-way bearing. to the pedal shaft. The power module of the electric power-assisted bicycle according to claim 1, wherein the reducer further includes an output gear and a fixed gear respectively disposed on the output shaft of the reducer and the fixed shaft of the reducer, the output gear and the fixed gear The gears are butted with each other to transmit the first torque when the output shaft of the reducer drives the output shaft of the gear plate to rotate.

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