A single-motor two-speed electric drive axle powertrain

Abstract

This utility model belongs to the field of new energy vehicle power transmission technology, and discloses a single-motor two-speed electric drive axle powertrain, including a disc motor, a reducer housing, a first shaft assembly, an intermediate shaft assembly, a reducer end cover, an axle housing, a first half-shaft, a differential, a second-stage reduction passive gear, a second half-shaft, a coupling sleeve, and a differential lock assembly. This solution achieves the advantages of compact structure, short axial dimension, and high power density by adopting an integrated design of an axial flux disc motor and a two-speed reduction mechanism, which is convenient for application in vehicles with high ground clearance requirements and limited installation space. By using a ball screw type shifting actuator in conjunction with motor speed adjustment, synchronizer-free rapid shifting is achieved, improving shifting smoothness and system reliability. The hollow intermediate shaft assembly and lubrication oil passage design make lubrication efficient and the structure simplified, improving operational reliability. The rear-mounted integrated differential lock assembly enhances the ability to get out of trouble in complex road conditions and the vehicle's adaptability.

Description

Technical Field

[0001] This utility model relates to the field of power transmission technology for new energy vehicles, and in particular to a single-motor two-speed electric drive axle powertrain. Background Technology

[0002] The electric drive axle powertrain mainly includes components such as a motor, reducer, and axle housing. It is responsible for transmitting the power output from the motor to the wheels through the reduction mechanism to achieve the vehicle's driving function.

[0003] A search of Chinese utility model patents (publication number CN110843440A) reveals an electric drive axle assembly with an integrated automatic transmission and suspension. By integrating the drive motor, automatic transmission, wheel ends, and independent suspension structure, the traditional drive shaft structure is eliminated, simplifying the system. The axle assembly has a compact structure, shortens the transmission chain, and improves transmission efficiency. The subframe structure ensures the installation and fixation of the power system and increases the versatility of the axle assembly. It features a two-speed automatic transmission, enabling gear shifting and speed adjustment. Furthermore, because the suspension uses a C-arm independent suspension structure, it can meet the requirements for a low ground clearance, while also improving the vehicle's handling stability and ride comfort.

[0004] However, practical application has revealed that this technical solution still has at least the following drawbacks:

[0005] The proposed solution features a motor shaft arranged perpendicularly to the output half-shaft and uses a spiral bevel gear drive, which is less efficient than a cylindrical gear drive. It employs a single-stage reduction, which cannot effectively coordinate the demands of high-speed driving and low-speed high torque. Furthermore, the structure is not compact enough and occupies a large amount of space. Utility Model Content

[0006] This utility model aims to provide a single-motor two-speed electric drive axle powertrain to solve the problems mentioned in the background art. This solution achieves the advantages of compact structure, short axial dimension and high power density by adopting an integrated design of axial flux disc motor and two-speed reduction mechanism, which is convenient for application in vehicles with high ground clearance requirements and limited installation space. By using a ball screw type shift actuator in conjunction with motor speed regulation, synchronizer-free rapid shifting is achieved, improving shifting smoothness and system reliability. The hollow intermediate shaft assembly and lubrication oil passage design make lubrication efficient and the structure simplified, improving operational reliability. The rear-mounted integrated differential lock assembly enhances the ability to get out of trouble in complex road conditions and the vehicle's adaptability, and optimizes the overall vehicle's power response, transmission efficiency and space adaptability.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] A single-motor two-speed electric drive axle powertrain includes a disc motor, a reducer housing, a first shaft assembly, an intermediate shaft assembly, a reducer end cover, an axle housing, a first half-shaft, a differential, a secondary reduction driven gear, a second half-shaft, a coupling sleeve, and a differential lock assembly. The disc motor is connected to the outer end of the reducer housing, and the output shaft of the disc motor is coaxially connected to the first shaft assembly. The first shaft assembly and the intermediate shaft assembly are connected by gear meshing. The intermediate shaft assembly meshes with the secondary reduction driven gear, which is connected to the differential via a spline. The differential is connected to both the first and second half-shafts. The differential lock assembly is installed on the rear side of the differential. The reducer end cover is closed at the end of the reducer housing. The axle housing completely covers the differential, the first half-shaft, and the second half-shaft.

[0009] Preferably, the disc motor adopts an axial flux structure and is cooled by a water-cooling structure.

[0010] Preferably, the engagement sleeve is positioned directly above the second half-shaft, and the engagement sleeve is connected to a ball screw type shifting actuator. The shifting actuator is connected to the reducer housing and is used to drive the engagement sleeve to move axially along the second half-shaft to achieve switching between different gears.

[0011] Preferably, the reducer housing and the axle housing are integrally formed, and the axle housing is directly mounted on the vehicle frame through a fixing structure, so that the axle housing and the subframe form a rigid closed loop.

[0012] Preferably, the intermediate shaft assembly is a hollow structure, and a lubricating oil passage is provided inside the intermediate shaft assembly. The lubricating oil passage supplies oil to the needle roller bearing on the intermediate shaft assembly through a small hole. The lubricating oil is stirred by the secondary reduction driven gear and flows into the oil passage through the oil collection port.

[0013] Preferably, the differential is connected to a differential lock assembly, which is located on the rear side of the differential and achieves the differential lock function through a mechanical connection structure.

[0014] The beneficial effects of this technical solution compared to existing technologies are as follows:

[0015] This solution achieves advantages such as compact structure, short axial dimension, and high power density through the integrated design of an axial flux disc motor and a two-speed reduction mechanism, making it suitable for application in vehicles with high ground clearance requirements and limited installation space. The ball screw-type shift actuator, combined with motor speed regulation, enables synchronizer-free rapid shifting, improving shift smoothness and system reliability. The hollow intermediate shaft assembly and lubrication channel design ensure efficient lubrication and a simplified structure, enhancing operational reliability. The rear-mounted integrated differential lock assembly enhances the vehicle's ability to overcome difficult road conditions and improves its adaptability, comprehensively optimizing the vehicle's power response, transmission efficiency, and space adaptability. Attached Figure Description

[0016] Figure 1 This is a top sectional view of the structure provided by this utility model.

[0017] Reference numerals in the attached drawings: 1. Disc motor; 2. Reducer housing; 3. First shaft assembly; 4. Intermediate shaft assembly; 5. Reducer end cover; 6. Axle housing; 7. First half-shaft; 8. Differential; 9. Secondary reduction driven gear; 10. Second half-shaft; 11. Engaging sleeve; 12. Differential lock assembly. Detailed Implementation

[0018] The electric drive axle powertrain mainly includes components such as a motor, reducer, and axle housing. It is responsible for transmitting the power output from the motor to the wheels through the reduction mechanism to achieve the vehicle's driving function.

[0019] Existing electric drive axle powertrains mostly adopt a vertical arrangement of the motor shaft and output half shaft, and use spiral bevel gear transmission in the transmission structure, resulting in low transmission efficiency; the reducer is generally a single-stage design, which makes it difficult to meet the needs of high-speed driving and low-speed high torque; in addition, the overall structure is not compact enough and the volume is large, making it difficult to meet the strict requirements for ground clearance and installation space.

[0020] In view of the above-mentioned defects, this utility model provides an electric drive axle powertrain with a compact structure, high transmission efficiency and multi-gear deceleration function to meet the vehicle application requirements of high power density, high reliability and high space layout.

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments:

[0022] like Figure 1 The single-motor two-speed electric drive axle powertrain shown includes a disc motor 1, a reducer housing 2, a first shaft assembly 3, an intermediate shaft assembly 4, a reducer end cover 5, an axle housing 6, a first half-shaft 7, a differential 8, a second-stage reduction driven gear 9, a second half-shaft 10, a coupling sleeve 11, and a differential lock assembly 12. The disc motor 1 is connected to the outer end of the reducer housing 2, and the output shaft of the disc motor 1 is coaxially connected to the first shaft assembly 3. The first shaft assembly 3 and the intermediate shaft assembly 4 are connected by gear meshing. The intermediate shaft assembly 4 is meshed with the second-stage reduction driven gear 9, which is connected to the differential 8 via a spline. The differential 8 is connected to the first half-shaft 7 and the second half-shaft 10 respectively. The differential lock assembly 12 is installed on the rear side of the differential 8. The reducer end cover 5 is closed at the end of the reducer housing 2. The axle housing 6 completely covers the differential 8, the first half-shaft 7, and the second half-shaft 10.

[0023] In this embodiment, the single-motor two-speed electric drive axle powertrain achieves the function of converting electrical energy into mechanical power and efficiently transmitting it to the wheels through the integrated design of disc motor 1, multi-stage reduction mechanism and axle housing 6. Its core lies in the fact that the power of disc motor 1 is progressively reduced in speed through gear meshing of the first shaft assembly 3 and intermediate shaft assembly 4, and then distributed to the first half-shaft 7 and the second half-shaft 10 through the second-stage reduction passive gear 9 and differential 8, thereby driving the wheels to rotate. The overall structure is compact, with a significantly shortened axial dimension, which helps to increase the vehicle's ground clearance. Two-speed switching is achieved through the coupling sleeve 11. During gear shifting, in conjunction with motor torque adjustment, smooth switching between low-speed high torque and high-speed cruising is possible, improving driving efficiency and vehicle adaptability. Furthermore, the integrated design of axle housing 6 enhances overall rigidity, reduces unsprung mass, and optimizes vehicle handling and comfort.

[0024] The disc motor 1 adopts an axial flux structure and is cooled by a water-cooling structure.

[0025] In this embodiment, the axial flux design of the disc motor 1 significantly shortens the axial dimension of the motor. Compared with the radial flux motor, it is more suitable for the space-constrained bridge housing 6 arrangement. The water-cooling structure can efficiently remove the heat generated during motor operation, avoid high temperature affecting motor performance and lifespan, and ensure the stability of power output under high load and continuous operation conditions. By connecting the motor 1 and the reducer housing 2 coaxially, the intermediate connection structure is reduced, the transmission efficiency is improved, and vibration and noise are reduced.

[0026] The engagement sleeve 11 is located directly above the second half-shaft 10, and the engagement sleeve 11 is connected to a ball screw type shifting actuator. The shifting actuator is connected to the reducer housing 2 and is used to drive the engagement sleeve 11 to move axially along the second half-shaft 10 to realize the switching of different gears.

[0027] In this embodiment, the engagement sleeve 11 is driven by a ball screw type shifting actuator and can move axially along the direction of the second half shaft 10 to realize the switching between first gear and second gear. The ball screw structure has the characteristics of high transmission efficiency and large output shifting force, which can ensure that the shifting action is completed quickly and accurately during vehicle operation. When shifting gears, combined with the speed adjustment of the motor 1, the gear meshing impact can be reduced, achieving smooth shifting, thereby improving the driving comfort and power response of the whole vehicle.

[0028] The reducer housing 2 and the axle housing 6 are integrally formed. The axle housing 6 is directly installed on the vehicle frame through a fixing structure, so that the axle housing 6 and the subframe form a rigid closed loop.

[0029] In this embodiment, the integrated design of the reducer housing 2 and the axle housing 6 reduces the number of component connections, improves the overall structural rigidity and sealing, and the axle housing 6 is directly fixed to the vehicle frame, so that the axle housing 6 and the subframe form a rigid closed loop, which can effectively resist the torque impact during the operation of the powertrain and improve the vehicle's driving stability. At the same time, this structure reduces the unsprung mass, which helps to improve the suspension response characteristics and improve the vehicle's handling performance and ride comfort.

[0030] The intermediate shaft assembly 4 is a hollow structure, and a lubricating oil passage is provided inside the intermediate shaft assembly 4. The lubricating oil passage supplies oil to the needle roller bearing on the intermediate shaft assembly 4 through a small hole. The lubricating oil is stirred by the secondary reduction driven gear 9 and flows into the oil passage through the oil collection port.

[0031] In this embodiment, the intermediate shaft assembly 4 is designed as a hollow structure, which reduces the weight of the assembly and facilitates the arrangement of lubrication channels inside the shaft. The lubrication channels guide the oil to the needle roller bearing through small holes for lubrication, reducing bearing friction and temperature rise. The secondary reduction passive gear 9 agitates the lubricating oil during operation, and the lubricating oil is circulated and supplied through the oil collection port, which simplifies the structure of the lubrication system and improves lubrication efficiency and system reliability.

[0032] The differential 8 is connected to the differential lock assembly 12, which is located on the rear side of the differential 8 and realizes the differential lock function through a mechanical connection structure.

[0033] In this embodiment, the differential 8 and the differential lock assembly 12 are arranged at the rear, which facilitates structural integration and maintenance. The differential lock assembly 12 works in conjunction with the differential 8 through a mechanical connection structure. When the vehicle is traveling on a low-traction road surface or when one wheel slips, the differential function of the differential 8 can be locked, which improves the vehicle's ability to get out of trouble and the stability of the driving force distribution, and enhances the vehicle's passability in complex road conditions.

[0034] The above descriptions are merely embodiments of this utility model. Commonly known technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solution of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A single-motor two-speed electric drive axle powertrain, characterized in that: The system includes a disc motor (1), a reducer housing (2), a first shaft assembly (3), an intermediate shaft assembly (4), a reducer end cover (5), a bridge housing (6), a first half-shaft (7), a differential (8), a second-stage reduction driven gear (9), a second half-shaft (10), a coupling sleeve (11), and a differential lock assembly (12). The disc motor (1) is connected to the outer end of the reducer housing (2), and the output shaft of the disc motor (1) is coaxially connected to the first shaft assembly (3). The first shaft assembly (3) and the intermediate shaft assembly (4) are connected by a... The gear meshing transmission connection is provided. The intermediate shaft assembly (4) meshes with the secondary reduction driven gear (9). The secondary reduction driven gear (9) is connected to the differential (8) via a spline. The differential (8) is connected to the first half-shaft (7) and the second half-shaft (10) respectively. The differential lock assembly (12) is installed on the rear side of the differential (8). The reducer end cover (5) is closed on the end of the reducer housing (2). The axle housing (6) completely covers the differential (8), the first half-shaft (7), and the second half-shaft (10).

2. The single-motor two-speed electric drive axle powertrain as described in claim 1, characterized in that: The disc motor (1) adopts an axial flux structure and is cooled by a water-cooling structure.

3. The single-motor two-speed electric drive axle powertrain as described in claim 1, characterized in that: The engagement sleeve (11) is located directly above the second half-shaft (10), and the engagement sleeve (11) is connected to a ball screw type shifting actuator. The shifting actuator is connected to the reducer housing (2) and is used to drive the engagement sleeve (11) to move axially along the second half-shaft (10) to realize the switching of different gears.

4. The single-motor two-speed electric drive axle powertrain as described in claim 1, characterized in that: The reducer housing (2) and the axle housing (6) are integrally formed. The axle housing (6) is directly installed on the vehicle frame through a fixed structure, so that the axle housing (6) and the subframe form a rigid closed loop.

5. The single-motor two-speed electric drive axle powertrain as described in claim 1, characterized in that: The intermediate shaft assembly (4) is a hollow structure, and a lubricating oil passage is provided inside the intermediate shaft assembly (4). The lubricating oil passage supplies oil to the needle roller bearing on the intermediate shaft assembly (4) through a small hole. The lubricating oil is stirred by the secondary reduction passive gear (9) and flows into the oil passage through the oil collection port.

6. The single-motor two-speed electric drive axle powertrain as described in claim 1, characterized in that: The differential (8) is connected to the differential lock assembly (12), which is located on the rear side of the differential (8) and realizes the differential lock function through a mechanical connection structure.

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