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CN-119176008-B - Electric drive assembly, four-wheel drive system and vehicle

CN119176008BCN 119176008 BCN119176008 BCN 119176008BCN-119176008-B

Abstract

The application belongs to the technical field of vehicle driving, and particularly relates to an electric driving assembly, a four-wheel drive system and a vehicle, wherein the electric driving assembly comprises a first motor, a second motor, a first speed reducer, a second speed reducer, a first half shaft and a second half shaft, the input end of the first speed reducer is connected with the first motor, the output end of the first speed reducer is connected with the first half shaft, the input end of the second speed reducer is connected with the second motor, the output end of the second speed reducer is connected with the second half shaft, and the decoupling rate sigma between the meshing frequency f z of a last-stage speed reducing gear set of the first speed reducer and the meshing frequency f y of a last-stage speed reducing gear set of the second speed reducer is greater than 8%, wherein the decoupling rate is determined according to the meshing frequency f z and the meshing frequency f y .

Inventors

  • YANG SHENGLIN
  • GAO YUAN
  • YANG NINGNING
  • ZHANG HEPENG
  • ZHANG HONGMING

Assignees

  • 比亚迪股份有限公司

Dates

Publication Date
20260505
Application Date
20220831

Claims (20)

  1. 1. The electric drive assembly is characterized by comprising a first motor, a second motor, a first speed reducer, a second speed reducer, a first half shaft and a second half shaft, wherein the input end of the first speed reducer is connected with the first motor, the output end of the first speed reducer is connected with the first half shaft, the input end of the second speed reducer is connected with the second motor, and the output end of the second speed reducer is connected with the second half shaft; The decoupling rate sigma between the meshing frequency f z of the first speed reducer final stage speed reducing gear set and the meshing frequency f y of the second speed reducer final stage speed reducing gear set is greater than 8%, wherein the decoupling rate is determined according to the meshing frequency f z and the meshing frequency f y .
  2. 2. The electric drive assembly of claim 1, wherein the frequency of engagement f z of the first-speed-reducer final-stage reduction gear set represents a number of times the first-speed-reducer final-stage reduction gear set is engaged when the first motor rotates one turn, the frequency of engagement f y of the second-speed-reducer final-stage reduction gear set represents a number of times the second-speed-reducer final-stage reduction gear set is engaged when the second motor rotates one turn, the decoupling ratio σ is represented by formula (1): Wherein f z represents the meshing frequency of the last-stage reduction gear set of the first speed reducer, f y represents the meshing frequency of the last-stage reduction gear set of the second speed reducer, abs (f z -f y ) represents the absolute value of the difference between f z and f y , and max (f z ,f y ) represents the maximum value between f z and f y .
  3. 3. An electric drive assembly according to claim 1 or 2, characterized in that, F z is represented by formula (2): f z ＝Z nzz *(i (n-1)z *......i 1z ) (2); in the formula (2), Z nzz represents the number of teeth of the drive gear of the last stage reduction gear set of the first reduction gear, and (i (n-1)z *......i 1z ) represents the cumulative multiplication of the speed ratios of the respective stages of reduction before the last stage reduction of the first reduction gear.
  4. 4. An electric drive assembly according to claim 1 or 2, characterized in that, In the formula (4), Z 2zz represents the number of teeth of the first-stage reduction driving gear, Z 1zz represents the number of teeth of the first-stage reduction driving gear, Z 1zc represents the number of teeth of the first-stage reduction driven gear, and i 1z represents the first-stage reduction speed ratio of the first reduction gear.
  5. 5. An electric drive assembly according to claim 1 or 2, characterized in that, F y is represented by formula (3): f y ＝Z myz *(i (m-1)y *......i 1y ) (3); In the formula (3), Z myz represents the number of teeth of the drive gear of the final stage reduction gear set of the second reduction gear, and (i (m-1)y *......i 1y ) represents the cumulative multiplication of the speed ratios of the respective stages of reduction before the final stage reduction of the second reduction gear.
  6. 6. An electric drive assembly according to claim 1 or 2, characterized in that, In the formula (5), Z 2yz represents the number of teeth of the second-stage reduction driving gear, Z 1yz represents the number of teeth of the second-stage reduction driving gear, Z 1yc represents the number of teeth of the second-stage reduction driven gear, and i 1 represents the first-stage reduction speed ratio of the second reduction gear.
  7. 7. The electric drive assembly of claim 1, wherein a speed ratio of the first reducer is different from a speed ratio of the second reducer.
  8. 8. The electric drive assembly of claim 1, wherein the first reducer is multi-stage reduction and the second reducer is multi-stage reduction; The first speed reducer and the second speed reducer have the same speed reduction stage number, and at least one corresponding stage speed ratio of the first speed reducer and the second speed reducer is different.
  9. 9. An electric drive assembly according to claim 1 or 8, wherein the first and second retarders are both two-stage retarders.
  10. 10. The electric drive assembly of claim 1, wherein at least two of the housing of the first speed reducer, the housing of the second speed reducer, the housing of the first motor, and the housing of the second motor are integrated.
  11. 11. The electric drive assembly according to claim 1 or 10, wherein the housing of the first motor and the housing of the second motor are integrated to form a motor housing, and the housing of the first speed reducer and the housing of the second speed reducer are separately arranged and fixedly connected to the left and right sides of the motor housing respectively.
  12. 12. The electric drive assembly of claim 1, wherein the rated rotational speed of the first motor is the same as the rated rotational speed of the second motor.
  13. 13. The electric drive assembly of claim 1, wherein the rated torque of the first motor and the second motor are the same.
  14. 14. The electric drive assembly of claim 1, wherein a larger one of the first and second retarders corresponds to a higher rated rotational speed of the motor and a smaller one of the first and second retarders corresponds to a higher rated torque of the motor.
  15. 15. The electric drive assembly of claim 1, wherein the first and second electric machines are disposed between the first and second reducers in a width direction of the vehicle, the first electric machine, the second electric machine, and the first half shaft are disposed in parallel, and an axial direction of the first and second half shafts passes through the second electric machine.
  16. 16. The electric drive assembly of claim 1, wherein the first reducer is a first parallel axis gear reducer and the second reducer is a second parallel axis gear reducer.
  17. 17. The electric drive assembly of claim 16, wherein the first parallel shaft gear reducer includes a first input shaft, a first intermediate shaft, and a first output shaft, the first input shaft, the first intermediate shaft, and the first output shaft being parallel and spaced apart from each other, the first input shaft being coaxially coupled with a motor shaft of the first motor, the first output shaft being coaxially coupled with the first half shaft.
  18. 18. The electric drive assembly of claim 17, wherein a first primary reduction drive gear is disposed on the first input shaft, a first primary reduction driven gear and a first secondary reduction drive gear are disposed on the first intermediate shaft, a first secondary reduction driven gear is disposed on the first output shaft, the first primary reduction drive gear and the first primary reduction driven gear are meshed to form a first stage reduction gear set of the first reducer, the first secondary reduction drive gear and the first secondary reduction driven gear are meshed to form a second stage reduction gear set of the first reducer, The number of teeth and the radius of the first primary reduction driving gear are smaller than those of the first primary reduction driven gear; the number of teeth and the radius of the first-stage reduction driving gear are smaller than those of the first-stage reduction driven gear.
  19. 19. The electric drive assembly of claim 16, wherein the second parallel shaft gear reducer includes a second input shaft, a second intermediate shaft, and a second output shaft, the second input shaft, the second intermediate shaft, and the second output shaft being parallel and spaced apart from each other, the second input shaft being coaxially coupled to a motor shaft of the second motor, the second output shaft being coaxially coupled to the second axle shaft.
  20. 20. The electric drive assembly of claim 19, wherein a second primary reduction drive gear is disposed on the second input shaft, a second primary reduction driven gear and a second secondary reduction drive gear are disposed on the second intermediate shaft, a second secondary reduction driven gear is disposed on the second output shaft, the second primary reduction drive gear and the second primary reduction driven gear are meshed to form a first stage reduction gear set of the second reducer, the second secondary reduction drive gear and the second secondary reduction driven gear are meshed to form a second stage reduction gear set of the second reducer, The number of teeth and the radius of the second primary reduction driving gear are smaller than those of the second primary reduction driven gear; the number of teeth and the radius of the second-stage reduction driving gear are smaller than those of the second-stage reduction driven gear.

Description

Electric drive assembly, four-wheel drive system and vehicle The application relates to a split application of China patent application with the name of electric drive assembly, four-wheel drive system and vehicle, which is filed on the 31 th month of 2022 and has the application number 202211057796.5. Technical Field The application belongs to the technical field of vehicle driving, and relates to an electric drive assembly, a four-wheel drive system and a vehicle. Background The torque and the speed of the left and right wheels of the dual-motor independently driven automobile can be accurately controlled independently of each other, thereby bringing a series of advantages to realize smaller radius turning, auxiliary ESP function, auxiliary steering function, auxiliary braking function and the like, and improving the steering performance of the automobile. Meanwhile, the motor driven independently can achieve higher dynamic property and stronger escaping performance. However, compared with a single-motor centralized-driving system, the centralized-arrangement double-motor wheel-side independent driving system sometimes has the problem of abnormal shaking or buzzing abnormal sound which affects the comfort of the whole vehicle. Disclosure of Invention Aiming at the problems that the existing driving system with the centralized double-motor wheel-side independent driving can sometimes generate abnormal jitter or buzzing abnormal sound which affect the comfort of the whole vehicle, the application provides an electric driving assembly, a four-wheel driving system and a vehicle. In order to solve the technical problems, in one aspect, the application provides an electric drive assembly, which comprises a first motor, a second motor, a first speed reducer, a second speed reducer, a first half shaft and a second half shaft, wherein the input end of the first speed reducer is connected with the first motor, the output end of the first speed reducer is connected with the first half shaft, the input end of the second speed reducer is connected with the second motor, the output end of the second speed reducer is connected with the second half shaft, and the decoupling rate sigma between the meshing frequency f z of a final-stage speed reducing gear set of the first speed reducer and the meshing frequency f y of the final-stage speed reducing gear set of the second speed reducer is greater than 8%, wherein the decoupling rate is determined according to the meshing frequency f z and the meshing frequency f y. According to the electric drive assembly disclosed by the embodiment of the application, the decoupling rate sigma between the meshing frequency f z of the last-stage reduction gear set of the first speed reducer and the meshing frequency f y of the last-stage reduction gear set of the second speed reducer is set to be more than 8%, and the decoupling rate is determined according to the meshing frequency f z and the meshing frequency f y. Through the arrangement, the problem of abnormal shaking or buzzing abnormal sound of the existing driving system with the centralized arrangement of the double motor wheel sides and the independent driving system can be effectively solved, driving feeling is good, and overall comfort is improved. On the other hand, the embodiment of the application also provides a four-wheel drive system which comprises a front drive axle and a rear drive axle, wherein the front drive axle is provided with the electric drive assembly. The four-wheel drive system of the embodiment of the application has all the advantages of the electric drive assembly. In yet another aspect, an embodiment of the present application further provides a vehicle including the electric drive assembly or the four-wheel drive system described above. The four-wheel drive system of the embodiment of the application has all the advantages of the electric drive assembly. Drawings FIG. 1 is a schematic illustration of an electric drive assembly provided in accordance with a first embodiment of the present application; FIG. 2 is a schematic illustration of an electric drive assembly provided in accordance with a second embodiment of the present application; FIG. 3 is a schematic view of an electric drive assembly provided by a third embodiment of the present application; FIG. 4 is a schematic view of an electric drive assembly provided by a fourth embodiment of the present application; FIG. 5 is a schematic view of an electric drive assembly provided by a fifth embodiment of the present application; FIG. 6 is a schematic view of an electric drive assembly provided by a sixth embodiment of the present application; FIG. 7 is a schematic view of an electric drive assembly provided by a seventh embodiment of the present application; FIG. 8 is a schematic view of an electric drive assembly provided by an eighth embodiment of the present application; FIG. 9 is a schematic view of an electric drive assembly provided by a ninth em