Transmission gearbox for parallel hybrid electric vehicles

• US 6,592,484 B1
• Filed: 08/09/2000
• Issued: 07/15/2003
• Est. Priority Date: 08/09/1999
• Status: Expired due to Fees

• Current Assignee: David Holloway, Gregory A. Schultz, Lung-Chu Tsai
• Original Assignee: David Holloway, Gregory A. Schultz, Lung-Chu Tsai
• Inventors: Schultz, Gregory A., Tsai, Lung-Wen
• Primary Examiner(s): Estremsky, Sherry
• Assistant Examiner(s): PANG, ROGER L
• Application Number:
  US09/635,315
• Time in Patent Office: 1,070 Days
• Field of Search: 475/5, 475/8, 180/65.2, 180/65.3, 180/65.4, 180/65.6, 180/65.7
• US Class Current: 475/5
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/115 with planetary gears
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/20 Control strategies involving selection of hybrid configuration, e.g. selection between series or parallel configuration
• CPC Class Codes: F16H 3/725 with means to change ratio in the mechanical gearing
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/91 Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/945 Characterized by control of gearing, e.g. control of transmission ratio
• CPC Class Codes: Y10S 903/946 Characterized by control of driveline clutch

Abstract

Disclosed is a novel parallel hybrid transmission that transmits torque from two power sources to the drive wheels of a vehicle. The transmission functions with a single heat engine and a single electric motor/generator. Through the use of a compound planetary gear train and four automatically controlled clutches, the transmission is able to (i) sum torque from the two power sources to drive the vehicle; (ii) split torque from the heat engine to drive the vehicle and charge the batteries; (iii) transmit torque individually from either of the two power sources; and (iv) operate as a one- or two-degree-of-freedom mechanism. The configuration of clutches and the compound planetary gear train enable thirteen modes of operation, namely, one motor-only mode, three combined motor and engine modes, one continuous variable transmission/charging mode, four engine-only modes, and four regenerative braking modes. Because the design is based on conventional automatic transmission components, the design is simple, compact, efficient, and reliable.

Claims

1. A transmission comprising:

an engine having an engine drive shaft;

an electric driving mechanism selectively operable as an electric motor and as a generator, said electric driving mechanism having a motor drive shaft;

an electric energy storage means in electrical communication with said electric driving mechanism;

a compound planetary gear set, said compound planetary gear set further comprising an input planetary gear train having a plurality of input gear train members, and an output planetary gear train having a plurality of output gear train members;

an output shaft operatively connected to said compound planetary gear set;

a first clutch positioned to selectively operatively connect said engine drive shaft to a first input gear train member;

a second clutch positioned to selectively operatively connect said engine drive shaft to a first output gear train member;

a third clutch positioned to selectively operatively connect said first output gear train member to a transmission case; and

a fourth clutch positioned to selectively operatively connect said motor drive shaft and one of each of said input gear train members and said output gear train members to said transmission case;

said first input gear train member comprising an input planetary gear carrier operatively connected to a plurality of input planetary gears, said input gear train member further comprising an input sun gear and an input ring gear, each of said input sun gear and said input ring gear engaging said plurality of input planetary gears; and

said first output gear train member comprising an output ring gear, said output gear train members further comprising an output sun gear and a plurality of output planetary gears engaging said output sun gear and said output ring gear and being operatively connected to an output planetary gear carrier.

2. The transmission of claim 1, wherein said input sun gear is conjoined with said output sun gear, and said input ring gear is conjoined with said output planetary gear carrier.

3. The transmission of claim 2, wherein said output planetary gear carrier is further fixedly attached to an intermediate mechanical drive means positioned between said output planetary gear carrier and said output shaft.

4. The transmission of claim 1, wherein engaging said third clutch and disengaging said first, second, and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque only from said electric driving mechanism to said output shaft.

5. The transmission of claim 1, wherein engaging said first and third clutches and disengaging said second and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque from said engine and said electric driving mechanism to said output shaft.

6. The transmission of claim 1, wherein engaging said second clutch and disengaging said first, third, and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque from said engine and said electric driving mechanism to said output shaft.

7. The transmission of claim 1, wherein engaging said first and second clutches and disengaging said third and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque from said engine and said electric driving mechanism to said output shaft.

8. The transmission of claim 1, wherein engaging said first clutch and disengaging said second, third, and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said engine to said output shaft and said electric driving mechanism.

9. The transmission of claim 1, wherein engaging said first and third clutches and disengaging said second and fourth clutches, and not driving said electric driving mechanism, transfers torque only from said engine to said output shaft.

10. The transmission of claim 1, wherein engaging said second and fourth clutches and disengaging said first and third clutches transfers torque only from said engine to said output shaft.

11. The transmission of claim 1, wherein engaging said first and second clutches and disengaging said third and fourth clutches, and not driving said electric driving mechanism, transfers torque only from said engine to said output shaft.

12. The transmission of claim 1, wherein engaging said first and fourth clutches and disengaging said second and third clutches transfers torque only from said engine to said output shaft.

13. The transmission of claim 1, wherein engaging said first and third clutches and disengaging said second and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft to said engine and said electric driving mechanism.

14. The transmission of claim 1, wherein engaging said second clutch and disengaging said first, third, and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft to said engine and said electric driving mechanism.

15. The transmission of claim 1, wherein engaging said first and second clutches and disengaging said third and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft to said engine and said electric driving mechanism.

16. The transmission of claim 1, wherein engaging said third clutch and disengaging said first, second, and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft only to said electric driving mechanism.

17. A transmission comprising:

an engine having an engine drive shaft;

an electric driving mechanism selectively operable as an electric motor and as a generator, said electric driving mechanism having a motor drive shaft;

an electric energy storage device in electrical communication with said electric driving mechanism;

a compound planetary gear set, said compound planetary gear set further comprising an input planetary gear train having a plurality of input gear train members, and an output planetary gear train having a plurality of output gear train members;

an output shaft operatively connected to said compound planetary gear set;

a first torque transfer device positioned to selectively operatively connect said engine drive shaft to a first input gear train member;

a second torque transfer device positioned to selectively operatively connect said engine drive shaft to a first output gear train member;

a third torque transfer device positioned to selectively operatively connect said first output gear train member to a transmission case; and

a fourth torque transfer device positioned to selectively operatively connect said motor drive shaft and one of each of said input gear train members and said output gear train members to said transmission case;

wherein said first input gear train member comprises an input planetary gear carrier operatively connected to a plurality of input planetary gears, said input gear train members further comprising an input sun gear and an input ring gear, each of said input sun gear and said input ring gear engaging said plurality of input planetary gears, and said first output gear train member comprising an output ring gear, said output gear train members further comprising an output sun gear and a plurality of output planetary gears engaging said output sun gear and said output ring gear and being operatively connected to an output planetary gear carrier.

18. The transmission of claim 17, wherein said input sun gear is conjoined with said output sun gear, and said input ring gear is conjoined with said output planetary gear carrier.

19. The transmission of claim 18, wherein said output planetary gear carrier is further fixedly attached to an intermediate mechanical drive means positioned between said output planetary gear carrier and said output shaft.

20. The transmission of claim 17, wherein engaging said third clutch and disengaging said first, second, and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque only from said electric driving mechanism to said output shaft.

21. The transmission of claim 17, wherein engaging said first and third clutches and disengaging said second and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque from said engine and said electric driving mechanism to said output shaft.

22. The transmission of claim 17, wherein engaging said second clutch and disengaging said first, third, and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque from said engine and said electric driving mechanism to said output shaft.

23. The transmission of claim 17, wherein engaging said first and second clutches and disengaging said third and fourth clutches, and operating said electric driving mechanism as an electric motor, transfers torque from said engine and said electric driving mechanism to said output shaft.

24. The transmission of claim 17, wherein engaging said first clutch and disengaging said second, third, and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said engine to said output shaft and said electric driving mechanism.

25. The transmission of claim 17, wherein engaging said first and third clutches and disengaging said second and fourth clutches, and not driving said electric driving mechanism, transfers torque only from said engine to said output shaft.

26. The transmission of claim 17, wherein engaging said second and fourth clutches and disengaging said first and third clutches transfers torque only from said engine to said output shaft.

27. The transmission of claim 17, wherein engaging said first and second clutches and disengaging said third and fourth clutches, and not driving said electric driving mechanism, transfers torque only from said engine to said output shaft.

28. The transmission of claim 17, wherein engaging said first and fourth clutches and disengaging said second and third clutches transfers torque only from said engine to said output shaft.

29. The transmission of claim 17, wherein engaging said first and third clutches and disengaging said second and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft to said engine and said electric driving mechanism.

30. The transmission of claim 17, wherein engaging said second clutch and disengaging said first, third, and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft to said engine and said electric driving mechanism.

31. The transmission of claim 17, wherein engaging said first and second clutches and disengaging said third and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft to said engine and said electric driving mechanism.

32. The transmission of claim 17, wherein engaging said third clutch and disengaging said first, second, and fourth clutches, and operating said electric driving mechanism as a generator, transfers torque from said output shaft only to said electric driving mechanism.

33. A transmission comprising:

a transmission case;

a first power source;

a second power source;

an electrical energy storage device in electrical communication with said second power source;

a compound planetary gear set;

an output shaft operatively connected to said compound planetary gear set; and

a plurality of torque transfer devices for selectively operatively connecting said first power source to said compound planetary gear set, and for connecting said second power source and at least a portion of said planetary gear set to said transmission case, said plurality of torque transfer devices being simultaneously operable to selectively;

(i) sum torque from said first and second power sources and transfer said summed torque to said output shaft;

(ii) split torque from said first power source to simultaneously transfer a first portion of said split torque to said output shaft and a second portion of said split torque to said second power source; and

(iii) transmit torque from only a single one of said first and second power sources to said output shaft;

said compound planetary gear set further comprising;

an input planetary gear train having a plurality of input gear train members, said

input gear train members further comprising;

an input sun gear, an input ring gear, and a plurality of input planetary gears engaging said input sun gear and said input ring gear and being operatively connected to an input planetary gear carrier; and

an output planetary gear train having a plurality of output gear train members, said output gear train members further comprising;

an output sun gear, an output ring gear, and a plurality of output planetary gears engaging said output sun gear and said output ring gear and being operatively connected to an output planetary gear carrier;

wherein said input sun gear is conjoined with said output sun gear, and said input ring gear is conjoined with said output planetary gear carrier.

34. The transmission of claim 33, wherein said output planetary gear carrier is further fixedly attached to an intermediate mechanical drive positioned between said output planetary gear carrier and said output shaft.

35. The transmission of claim 33, said first power source further comprising a first drive shaft, and said second power source further comprising a second drive shaft, wherein:

said first drive shaft is selectively operatively attached to said input planetary gear carrier, said output ring gear, and both said input planetary gear carrier and said output ring gear simultaneously;

said input sun gear and said output sun gear are fixedly attached to said second drive shaft; and

said output planetary gear carrier is operatively attached to said output shaft.

36. The transmission of claim 33, said first power source further comprising a first drive shaft, said second power source further comprising a second drive shaft, and said plurality of torque transfer devices further comprising:

a first clutch selectively operatively connecting said first drive shaft to said input planetary gear carrier;

a second clutch selectively operatively connecting said first drive shaft to said output ring gear;

a third clutch selectively operatively connecting said output ring gear to a transmission case; and

a fourth clutch selectively operatively connecting said second drive shaft, said input sun gear, and said output sun gear to said transmission case.

37. The transmission of claim 36, wherein said third and fourth clutches comprise band clutches.

38. The transmission of claim 33, wherein said first power source comprises a heat engine, and said second power source comprises a combined electric motor and generator.

39. The transmission of claim 38, said plurality of torque transfer devices being further simultaneously operable to selectively transfer torque from said electric motor and said output shaft to said heat engine when said heat engine is in a nonoperational state in order to start operation of said heat engine.

40. A transmission comprising:

a transmission case;

a first power source;

a second power source;

an electrical energy storage device in electrical communication with said second power source;

a compound planetary gear set;

an output shaft operatively connected to said compound planetary gear set; and

a plurality of torque transfer devices for selectively operatively connecting said first power source to said compound planetary gear set, and for connecting said second power source and at least a portion of said planetary gear set to said transmission case, said plurality of torque transfer devices being simultaneously operable to selectively;

(i) transfer torque only from said first power source to said output shaft;

(ii) transfer torque only from said second power source to said output shaft;

(iii) transfer combined torque from each of said first and second power sources to said output shaft;

(iv) function simultaneously as a continuous variable transmission and charger for said electrical energy storage device;

(v) transfer torque from said output shaft to said second power source to direct electrical energy from said second power source to said electrical energy storage device;

(vi) transfer torque from said output shaft to said first power source to provide engine braking; and

(vii) transfer torque to said first and second power sources simultaneously;

said compound planetary gear set further comprising;

an input planetary gear train having a plurality of input gear train members, said

input gear train members further comprising;

an input sun gear, an input ring gear, and a plurality of input planetary gears engaging said input sun gear and said input ring gear and being operatively connected to an input planetary gear carrier; and

an output planetary gear train having a plurality of output gear train members, said output gear train members further comprising;

an output sun gear, an output ring gear, and a plurality of output planetary gears engaging said output sun gear and said output ring gear and being operatively connected to an output planetary gear carrier;

wherein said input sun gear is conjoined with said output sun gear, and said input ring gear is conjoined with said output planetary gear carrier.

41. The transmission of claim 40, wherein said output planetary gear carrier is further fixedly attached to an intermediate mechanical drive positioned between said output planetary gear carrier and said output shaft.

42. The transmission of claim 40, said first power source further comprising a first drive shaft, and said second power source further comprising a second drive shaft, wherein:

said first drive shaft is selectively operatively attached to said input planetary gear carrier, said output ring gear, and both said input planetary gear carrier and said output ring gear simultaneously;

said input sun gear and said output sun gear are fixedly attached to said second drive shaft; and

said output planetary gear carrier is operatively attached to said output shaft.

43. The transmission of claim 40, said first power source further comprising a first drive shaft, said second power source further comprising a second drive shaft, and said means for selectively and operatively connecting said first and second power sources to said compound gear set further comprising:

a first clutch selectively operatively connecting said first drive shaft to said input planetary gear carrier;

a second clutch selectively operatively connecting said first drive shaft to said output ring gear;

a third clutch selectively operatively connecting said output ring gear to a transmission case; and

a fourth clutch selectively operatively connecting said second drive shaft to said transmission case.

44. The transmission of claim 43, wherein said third and fourth clutches comprise band clutches.

45. The transmission of claim 40, wherein said first power source comprises a heat engine, and said second power source comprises a combined electric motor and generator.

46. The transmission of claim 45, said plurality of torque transfer devices being simultaneously operable to selectively transfer torque from said electric motor and said output shaft to said heat engine when said heat engine is in a nonoperational state in order to start operation of said heat engine.

47. The transmission of claim 46, said plurality of torque transfer devices being simultaneously operable to selectively transfer torque from said electric motor and said output shaft to said heat engine when said heat engine is in a nonoperational state in order to start operation of said heat engine.