Power transmission system and vehicle comprising the same

• US 9,568,066 B2
• Filed: 03/11/2015
• Issued: 02/14/2017
• Est. Priority Date: 09/10/2014
• Status: Active Grant

• Current Assignee: BYD Company Limited
• Original Assignee: BYD Company Limited
• Inventors: Yang, Dongsheng, Lian, Yubo, Zhang, Jintao, Luo, Hongbin
• Primary Examiner(s): Ho, Ha D
• Application Number:
  US14/644,943
• Publication Number:
  US 20160069427A1
• Time in Patent Office: 706 Days
• Field of Search: 743/30, 743/31, 743/33, 743/40, 746/61
• US Class Current: 1/1
• CPC Class Codes: B60K 17/165 provided between independent half axles B60K17/18, B60K17/20 take precedence
• CPC Class Codes: B60K 17/356 having fluid or electric motor, for driving one or more wheels disposition of motor in, or adjacent to, traction wheel B60K7/00
• CPC Class Codes: B60K 2007/0046 the motor moving together with the vehicle body, i.e. moving independently from the wheel axle
• CPC Class Codes: B60K 2007/0061 the motor axle being parallel to the wheel axle
• CPC Class Codes: B60K 6/442 Series-parallel switching type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60K 7/0007 the motor being electric
• CPC Class Codes: F16H 2003/0807 with gear ratios in which the power is transferred by axially coupling idle gears
• CPC Class Codes: F16H 2003/0822 characterised by the arrangement of at least one reverse gear
• CPC Class Codes: F16H 2003/0931 each countershaft having an output gear meshing with a single common gear on the output shaft
• CPC Class Codes: F16H 2200/0056 the gear ratios comprising seven forward speeds
• CPC Class Codes: F16H 3/006 power being selectively transmitted by either one of the parallel flow paths
• CPC Class Codes: F16H 3/093 with two or more countershafts
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/917 with transmission for changing gear ratio

Abstract

A power transmission system for a vehicle includes: an engine; a plurality of input shafts, wherein at least one of the input shafts is configured to selectively engage with the engine; a plurality of output shafts configured to mesh with a corresponding shift driving gear; a transmission gear provided on one of the output shafts; a motor power shaft; a first and a second motor gears fitted over the motor power shaft; a motor synchronizer; a reverse gear fitted over the motor power shaft; a middle idler configured to mesh with the shift driving gear provided on one of the input shafts; a reverse idler gear configured to mesh with the reverse gear and to selectively rotate together with the middle idler; and a first motor generator configured to operate correspondingly with the motor power shaft. A vehicle including the power transmission system is also provided.

Claims

1. A power transmission system for a vehicle, comprising:

an engine;

a plurality of input shafts, wherein at least one of the input shafts is configured to selectively engage with the engine, each of the input shafts being provided with a shift driving gear thereon;

a plurality of output shafts, wherein each of the output shafts is provided with a shift driven gear configured to mesh with a corresponding shift driving gear;

a transmission gear provided on one of the output shafts;

a motor power shaft;

a first motor gear and a second motor gear both fitted over the motor power shaft;

a motor synchronizer disposed on the motor power shaft and between the first and second motor gears;

a reverse gear fitted over the motor power shaft;

a middle idler configured to mesh with the shift driving gear provided on one of the input shafts;

a reverse idler gear configured to mesh with the reverse gear and to selectively rotate together with the middle idler, wherein the first motor gear is configured to mesh with the middle idler, and the second gear is configured to mesh with the transmission gear; and

a first motor generator configured to operate together with the motor power shaft.

2. The power transmission system according to claim 1, further comprising a reverse synchronizer configured to synchronize the middle idler and the reverse idler gear.

3. The power transmission system according to claim 1, wherein the reverse idler gear comprises a gear sleeve, and the middle idler is fitted over the gear sleeve.

4. The power transmission system according to claim 3, wherein the reverse synchronizer is disposed on the gear sleeve and configured to engage with the middle idler, and/or the reverse synchronizer is disposed on the middle idler and configured to engage with the gear sleeve or with the reverse idler gear.

5. The power transmission system according to claim 1, wherein the plurality of input shafts comprises a first input shaft and a second input shaft coaxially fitted over the first input shaft;

wherein the plurality of output shafts comprises a first output shaft and a second output shaft parallel to respectively the first and second input shafts;

wherein the power transmission system further comprises a dual clutch comprising;

an input terminal connected with the engine, a first output terminal coupled with the first input shaft, and a second output shaft coupled with the second input shaft.

6. The power transmission system according to claim 5, wherein the plurality of shift driving gears comprise a first-gear driving gear disposed on the first input shaft, a second-gear driving gear disposed on the second input shaft, a third-gear driving gear disposed on the first input shaft, a fourth-gear driving gear disposed on the second input shaft, and a fifth-gear driving gear disposed on the first input shaft;

wherein the plurality of shift driven gears comprise first-gear to fourth-gear driven gears disposed on the first output shaft, and a fifth-gear driven gear disposed on the second output shaft; and

wherein the power transmission system further comprise a first-third gear synchronizer disposed between the first-gear driven gear and the third-gear driven gear, a second-fourth synchronizer disposed between the second-gear driven gear and the fourth-gear driven gear, and a fifth gear synchronizer disposed at a side of the fifth-gear driven gear.

7. The power transmission system according to claim 6, wherein the reverse idler gear is fitted over the second output shaft, wherein the middle idler is configured to mesh with the second-gear driving gear, and wherein the transmission gear is fixed on the second output shaft.

8. The power transmission system according to claim 6, wherein the reverse synchronizer and the fifth gear synchronizer share a shift fork mechanism.

9. The power transmission system according to claim 1, wherein the reverse gear is a duplex gear comprising a first part configured to mesh with the reverse idler gear and a second part configured to mesh with a driven gear of a main reducer of the vehicle.

10. The power transmission system according to claim 9, further comprising a first output gear fixed on the first output shaft and a second output gear fixed on the second output shaft, wherein the first and second output gears are both configured to mesh with the driven gear of the main reducer.

11. The power transmission system according to claim 5, wherein the engine is configured to engage the input terminal of the dual clutch with the first output terminal and the second output terminal of the dual clutch simultaneously to transmit a first part of power to one or more wheels of the vehicle via one of the output shafts, and to transmit a second part of power to the first motor generator via the motor power shaft to cause the first motor generator to generate electric power.

12. The power transmission system according to claim 1, wherein the engine is configured to transmit power to one of the input shafts, and to transmit the power to the first motor generator;

wherein the motor synchronizer disposed on the motor power shaft is configured to synchronize with the first gear to cause the first motor generator to generate electric power, when the vehicle is in a parking state.

13. The power transmission system according to claim 5, wherein the vehicle includes a mechanical reverse mode, an electric reverse mode and a hybrid reverse mode, wherein:

when the vehicle is in the mechanical reverse mode, the engine is configured to generate a first power, to transmit the first power to one of the input shafts, and to transmit the first power to the reverse gear via synchronization of the reverse synchronizer;

when the vehicle is in an electric reverse mode, the first motor generator is configured to generate a second power and to transmit the second power to the reverse gear via synchronization of the reverse synchronizer and via synchronizing the first motor gear by the motor synchronizer disposed on the motor power shaft; and

when the vehicle is in a hybrid reverse mode, the engine is configured to generate a first power, to transmit the first power to one of the input shafts, and to transmit the first power to the reverse gear via synchronization of the reverse synchronizer, and the first motor generator is configured to generate a second power and to transmit the second power the reverse gear via synchronization of the reverse synchronizer and via synchronizing the first motor gear by the motor synchronizer disposed on the motor power shaft.

14. The power transmission system according to claim 7, wherein the vehicle has a mechanical reverse mode, an electric reverse mode and a hybrid reverse mode, wherein

when the vehicle is in the mechanical reverse mode, the engine is configured to generate a first power, to transmit the first power to one of the input shafts, and to transmit the first power to the reverse gear via synchronization of the reverse synchronizer;

when the vehicle is in an electric reverse mode, the first motor generator is configured to generate a second power and to output the second power from the second output shaft via synchronizing the second gear by the motor synchronizer disposed on the motor power shaft; and

when the vehicle is in a hybrid reverse mode, the engine is configured to generate a first power, to transmit the first power to one of the input shafts, and to transmit the first power to the reverse gear via synchronization of the reverse synchronizer, and the first motor generator is configured to generate a second power and to output the second power from the second output shaft via synchronizing the second gear by the motor synchronizer disposed on the motor power shaft.

15. The power transmission system according to claim 1, wherein the first motor generator is configured to rotate along a predetermined direction when operating as a motor or a generator.

16. The power transmission system according to claim 1, wherein when the motor synchronizer disposed on the motor power shaft switches from engaging with one of the first and second motor gears to engaging with the other of the first and second motor gears, the first motor generator is configured to adjust a rotating speed of the motor power shaft with a rotating speed of the other of the first and second motor gears as a target speed.

17. The power transmission system according to claim 4, further comprising a second motor generator, wherein the second motor generator is configured to perform power transmission with a driven gear of a main reducer of the vehicle, or is connected with the first output shaft, or is connected with the first input shaft, or the driven gear of the main reducer is disposed on a differential of the vehicle with two second motor generators being provided and disposed on two sides of the differential respectively.

18. The power transmission system according to claim 1, wherein the engine and/or the first motor generator is configured to drive a first pair of wheels of the vehicle, and the power transmission system further comprises:

a third motor generator configured to rotate together with one of a second pair of wheels of the vehicle;

a fourth motor generator configured to rotate together with the other one of the second pair of wheels of the vehicle, wherein the first pair of wheels are one pair of a pair of front wheels and a pair of rear wheels of the vehicle, and the second pair of wheels are the other pair of the pair of front wheels and the pair of rear wheels; and

an antiskid synchronizer configured to selectively synchronize the second pair of wheels.

19. The power transmission system according to claim 18, further comprising

a first gear disposed on a first power output shaft corresponding to the third motor generator;

a second gear disposed on a first drive shaft connected with a wheel corresponding to the third motor generator;

a third gear configured to mesh with the first gear;

a fourth gear coaxially arranged with the third gear and configured to mesh with the second gear and to rotate together with the third gear;

a fifth gear disposed on a second power output shaft corresponding to the fourth motor generator;

a sixth gear disposed on a second drive shaft connected with a wheel corresponding to the fifth motor generator;

a seventh gear configured to mesh with the fifth gear; and

an eighth gear coaxially arranged with the seventh gear and configured to mesh with the sixth gear and to rotate together with the eighth gear;

wherein the antiskid synchronizer is disposed on the first drive shaft and configured to selectively engage with the sixth gear;

or the antiskid synchronizer is disposed on the first power output shaft corresponding to the third motor generator and is configured to selectively engage with the fifth gear;

or the third gear and the fourth gear are fixed on a first gear shaft, the seventh gear and the eighth gear are fixed on a second gear shaft, and the antiskid synchronizer is disposed on the first gear shaft and configured to selectively engage with the seventh gear.

20. The power transmission system according to claim 19, wherein the first power output shaft is coaxially coupled with a wheel corresponding to the first output shaft, the second power output shaft is coaxially connected with a wheel corresponding to the second output shaft, the antiskid synchronizer is disposed on the first power output shaft and configured to engage with the second power output shaft.

21. A power transmission system for a vehicle, comprising

a dual clutch comprising an input terminal, a first output terminal and a second output terminal;

an engine coupled with the input terminal of the dual clutch;

a first input shaft coupled with the first output terminal of the dual clutch;

a second input shaft fitted over the first input shaft and coupled with the second output terminal of the dual clutch, wherein each of the first and second input shafts is provided with a shift driving gear;

a first output shaft and a second output shaft, wherein each of the first and second output shafts is provided with a shift driven gear configured to mesh with a corresponding shift driving gear;

a first output gear fixed on the first output shaft;

a second output gear fixed on the second output shaft;

a motor power shaft;

first and second motor gears fitted over the motor power shaft;

a reverse gear fitted over the motor power shaft;

a motor synchronizer disposed on the motor power shaft and between the first and second motor gears, wherein the first motor gear is configured to perform power transmission with the shift driving gear on one of the first and second input shafts via a middle idler, the second motor gear is configured to perform power transmission with a transmission gear fixed on one of the first and second output shafts, and the reverse gear, the first motor gear and the second motor gear mesh with a driven gear of a main reducer of the vehicle;

a reverse idler gear configured to mesh with the reverse gear;

a reverse synchronizer configured to engage the reverse idler gear and the middle idler; and

a first motor generator connected with the motor power shaft.

22. The power transmission system for a vehicle according to claim 21, further comprising

a first-gear driving gear disposed on the first input shaft;

a second-gear driving gear disposed on the second input shaft;

a third-gear driving gear disposed on the first input shaft;

a fourth-gear driving gear disposed on the second input shaft

a fifth-gear driving gear disposed on the first input shaft;

first-gear to fourth-gear driven gears disposed on the first output shaft; and

a fifth-gear driven gear disposed on the second output shaft;

wherein the first motor gear is configured to perform power transmission with the second-gear driving gear via the middle idler;

wherein the transmission gear is fixed on the second output shaft;

wherein the reverse idler gear is fitted over the second output shaft and comprises a gear sleeve;

wherein the middle idler is fitted over the gear sleeve, and wherein the reverse synchronizer is disposed on the gear sleeve and is configured to engage with the middle idler.

23. The power transmission system according to claim 21, further comprising a second motor generator;

wherein the second motor generator is configured to perform power transmission with the driven gear of the main reducer, or is connected with the first output shaft, or is connected with the first input shaft;

or the driven gear of the main reducer is disposed on a differential of the vehicle with two second motor generators being provided and disposed on two sides of the differential.

24. The power transmission system according to claim 21, wherein the driven gear of the main reducer is disposed on a differential of the vehicle, the differential is disposed between a pair of front wheels of the vehicle, and the power transmission system further comprises:

a third motor generator configured to rotate together with one of a pair of rear wheels of the vehicle;

a fourth motor generator configured to rotate together with the other one of the pair of rear wheels of the vehicle; and

an antiskid synchronizer configured to selectively synchronize the pair of rear wheels of the vehicle.