Power-assisted gear transmission structure of middle motor
By adding a human input shaft outside the mid-motor, using manpower to improve the output power of the mid-motor, the problem of high transmission ratio mid-motor compact structure and low output torque is solved, and the uphill and acceleration of the electric bicycle is achieved Power demand under operating conditions such as overtaking and reducing system costs.
Patent Information
- Application Number
- CN202420417151.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-05
- Publication Date
- 2025-02-25
- Estimated Expiration
- 2034-03-05
AI Technical Summary
In the field of mid-mounted motors, it is difficult to take into account the compact structure while having high transmission ratios. It usually requires the use of expensive and complex planetary wheel transmission systems, resulting in high costs and low output torque, making it difficult to meet the needs of electric bicycles on uphill, acceleration, overtaking, etc. Requirements under operating conditions.
A power-assisted gear transmission structure of a low-power mid-motor was designed. By adding a first-level human input shaft outside the mid-motor, manpower was used to help improve the output power of the mid-motor, and the insufficient output power in the non-planetary wheel transmission system was overcome. The problem.
With manpower, the final output power of the mid-mounted motor is improved, meeting the requirements of electric bicycles under conditions such as uphill, acceleration, and overtaking, while reducing system costs.
Smart Images
Figure CN222531455U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field of mid-mounted motors. Background Art
[0002] In the field of mid-mounted motors, when a high transmission ratio is required while taking into account the goal of compact structure, a sophisticated and expensive planetary gear transmission system is generally required. The planetary gear transmission system has the disadvantages of complex structure and high cost. If the high-cost planetary gear transmission system is not used in the limited motor space, the overall output torque of the mid-mounted motor will be low. If this mid-mounted motor is used in the field of electric bicycles, it cannot adapt well to the requirements of working conditions such as uphill, acceleration, and overtaking. Summary of the invention
[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the utility model provides a power-assisting gear transmission structure for a low-power mid-mounted motor, which provides power assistance to the low-power motor through manpower, so that the low-cost mid-mounted motor can also achieve the output performance of a high-performance motor.
[0004] Technical solution: To achieve the above-mentioned purpose, the utility model provides a power-assisted gear transmission structure of a mid-mounted motor, comprising a human input shaft, a mid-mounted motor output shaft, a rotor shaft, a first power-assisted toothed disc, a second power-assisted toothed disc, an output toothed disc, a first transmission gear and a second transmission gear;
[0005] The first power-assisting gear plate, the output gear plate and the first transmission gear are synchronously connected to the human input shaft, the mid-mounted motor output shaft and the rotor shaft respectively and coaxially;
[0006] The second power-assisting gear plate and the inner ring of the second transmission gear are respectively matched with the output shaft of the central motor through the first overrunning clutch and the second overrunning clutch to drive coaxially;
[0007] The first power-assisting toothed disc is connected to the second power-assisting toothed disc through a flexible member, and the first transmission gear is meshed with the second transmission gear.
[0008] Furthermore, it comprises a central motor housing, in which the central motor output shaft, the second transmission gear and the rotor shaft are rotatably mounted.
[0009] Furthermore, a motor stator is fixedly installed in the central motor housing, a motor rotor is coaxially arranged in the motor stator, and the motor rotor is coaxially and synchronously installed on the rotor shaft.
[0010] Furthermore, the flexible member is a toothed silent belt.
[0011] Furthermore, the human input shaft is rotatably installed in the five-way sleeve of the bicycle.
[0012] Furthermore, the human input shaft, the mid-mounted motor output shaft and the rotor shaft are parallel to each other.
[0013] Beneficial effect: The utility model adds a first-level human input shaft to the outside of the low-cost, low-power mid-mounted motor of the non-planetary gear transmission system. On the basis of not changing the original low-cost mid-mounted motor, the power of the final output of the mid-mounted motor to the output gear plate is increased through the assistance of human power, thus overcoming the problem of insufficient output power of the mid-mounted motor of the low-cost non-planetary gear transmission system. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Attached Figure 1 This is a schematic diagram of the transmission structure of this scheme. DETAILED DESCRIPTION
[0015] The utility model is further described below in conjunction with the accompanying drawings.
[0016] As attached Figure 1 The power-assisted gear transmission structure of a mid-mounted motor shown in the figure includes a human input shaft 2, a mid-mounted motor output shaft 5, a rotor shaft 6, a first power-assisted sprocket 1, a second power-assisted sprocket 3, an output sprocket 15, a first transmission gear 12, a second transmission gear 18 and a mid-mounted motor housing fixedly mounted on the power-assisted bicycle frame; the human input shaft 2, the mid-mounted motor output shaft 5 and the rotor shaft 6 are arranged parallel to each other.
[0017] The first power-assisting sprocket 1, the output sprocket 15 and the first transmission gear 12 are respectively coaxially synchronized on the human input shaft 2, the mid-mounted motor output shaft 5 and the rotor shaft 6; the human input shaft 2 is rotatably mounted in the bicycle five-way sleeve through a pair of first bearings 19, and the human input shaft 2 is connected to the pedal crank for human input; the output sprocket 15 drives the rear wheel of the bicycle to rotate through an output chain or a toothed belt.
[0018] The inner rings of the second power-assisting sprocket 3 and the second transmission gear 18 are respectively coaxially matched with the output shaft 5 of the mid-mounted motor through the first overrunning clutch 4 and the second overrunning clutch 13; in the present case, the first overrunning clutch 4 is a one-way needle bearing; the second overrunning clutch 13 is a ratchet pawl structure; the first power-assisting sprocket 1 and the second power-assisting sprocket 3 are connected through a flexible member 21, which is a toothed silent belt or chain. The design of the flexible member 21 makes the positional relationship between the five-way shaft and the output shaft 5 of the mid-mounted motor more flexible and changeable, so that the installation position of the mid-mounted motor is not restricted by the position of the five-way shaft.
[0019] The first transmission gear 12 is meshed with the second transmission gear 18; the mid-mounted motor output shaft 5, the second transmission gear 18 and the rotor shaft 6 are rotatably mounted in the mid-mounted motor housing through a second bearing 8, a pair of third bearings 17 and a pair of fourth bearings 7 respectively; in order to enhance the transmission stability of the second overrunning clutch 13, a fifth bearing 14 is further installed between the inner ring of the second transmission gear 18 and the mid-mounted motor output shaft 5; a motor stator 10 is fixedly installed in the mid-mounted motor housing, a motor rotor 9 is coaxially arranged in the motor stator 10, and the motor rotor 9 is coaxially and synchronously mounted on the rotor shaft 6.
[0020] Working principle:
[0021] During operation, the torque output by the motor rotor 9 is transmitted to the mid-mounted motor output shaft 5 through the transmission of the first transmission gear 12 and the second transmission gear 18, and is finally output through the output sprocket 15. Due to the limited space of the mid-mounted motor housing, the transmission ratio between the first transmission gear 12 and the second transmission gear 18 is limited. Therefore, the power and torque finally transmitted by the motor rotor 9 to the mid-mounted motor output shaft 5 are low, which cannot well meet the requirements of working conditions such as going uphill, accelerating, and overtaking. At this time, human power inputs a human torque to the human power input shaft 2 through the pedal crank, and then the human power torque is transmitted to the mid-mounted motor output shaft 5 through the flexible member 21, thereby achieving the purpose of providing assistance to the mid-mounted motor output shaft 5 through human power, thereby increasing the power of the mid-mounted motor's final output to the output sprocket, and overcoming the problem of insufficient output power of the mid-mounted motor of the low-cost non-planetary gear transmission system under working conditions such as going uphill, accelerating, and overtaking of electric bicycles.
[0022] On a flat road or downhill section, when there is no human power output and the motor rotor 9 outputs power, the first overrunning clutch 4 automatically enters a disengaged state, thereby avoiding the problem of further reducing the power of the dragging flexible member 21 in the pure electric output mode;
[0023] When the battery is out of power, human power is output to the human power input shaft 2 through the pedal crank, and the motor rotor 9 does not output, the second overrunning clutch 13 automatically enters a disengaged state, thereby avoiding the laborious situation of dragging the second transmission gear 18 in pure human power mode.
[0024] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.
Claims
1. A power-assisting gear transmission structure of a mid-mounted motor, characterized in that: It comprises a human input shaft (2), a mid-mounted motor output shaft (5), a rotor shaft (6), a first power-assisting gear disc (1), a second power-assisting gear disc (3), an output gear disc (15), a first transmission gear (12) and a second transmission gear (18); The first power-assisting gear disc (1), the output gear disc (15) and the first transmission gear (12) are respectively coaxially synchronized on the human input shaft (2), the mid-mounted motor output shaft (5) and the rotor shaft (6); The inner ring of the second power-assisting toothed disc (3) and the second transmission gear (18) are respectively coaxially coupled with the output shaft (5) of the central motor through the first overrunning clutch (4) and the second overrunning clutch (13); The first power-assisting toothed disc (1) and the second power-assisting toothed disc (3) are connected in transmission via a flexible member (21), and the first transmission gear (12) and the second transmission gear (18) are meshed.
2. The power-assisting gear transmission structure of a mid-mounted motor according to claim 1, characterized in that: It comprises a central motor housing, wherein the central motor output shaft (5), the second transmission gear (18) and the rotor shaft (6) are rotatably mounted in the central motor housing.
3. The power-assisting gear transmission structure of a mid-mounted motor according to claim 2, characterized in that: A motor stator (10) is fixedly installed in the central motor housing, a motor rotor (9) is coaxially arranged in the motor stator (10), and the motor rotor (9) is coaxially and synchronously installed on the rotor shaft (6).
4. The power-assisting gear transmission structure of a mid-mounted motor according to claim 1, characterized in that: The flexible member (21) is a toothed silent belt.
5. The power-assisting gear transmission structure of a mid-mounted motor according to claim 4, characterized in that: The human input shaft (2) is rotatably mounted in a five-way sleeve of the bicycle.
6. The power-assisting gear transmission structure of a mid-mounted motor according to claim 1, characterized in that: The human input shaft (2), the central motor output shaft (5) and the rotor shaft (6) are parallel to each other.