Drivetrain with hybrid transfer case

• US 20030148843A1
• Filed: 01/22/2003
• Published: 08/07/2003
• Est. Priority Date: 10/19/2001
• Status: Active Grant

• Current Assignee: Thomas C. Bowen
• Original Assignee: Thomas C. Bowen
• Inventors: Bowen, Thomas C.
• Granted Patent: US 6,719,656 B2
• Time in Patent Office: Days
• US Class Current: 475/5
• CPC Class Codes: B60K 17/34 for driving both front and rear wheels, e.g. four wheel drive vehicles arrangement or mounting of control devices for changing number of driven wheels B60K23/08
• CPC Class Codes: B60K 23/08 for changing number of driven wheels , for switching from driving one axle to driving two or more axles B60K17/3515 takes precedence
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/387 Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means
• CPC Class Codes: B60K 6/405 Housings
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/461 Speed
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2250/24 : by lever actuation
• CPC Class Codes: B60L 2250/26 : by pedal actuation
• CPC Class Codes: B60L 50/16 : with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 58/12 : responding to state of charge [SoC]
• CPC Class Codes: B60L 7/14 : for vehicles propelled by ac motors
• CPC Class Codes: B60W 10/02 : including control of driveline clutches
• 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 20/00 : Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/40 : Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: F16H 3/725 : with means to change ratio in the mechanical gearing
• CPC Class Codes: H02K 7/006 : Structural association of a motor or generator with the drive train of a motor vehicle
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y10S 903/906 : Motor or generator
• CPC Class Codes: Y10S 903/91 : Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/914 : Actuated, e.g. engaged or disengaged by electrical, hydraulic or mechanical means
• CPC Class Codes: Y10S 903/916 : with plurality of drive axles
• CPC Class Codes: Y10S 903/917 : with transmission for changing gear ratio
• 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
• CPC Class Codes: Y10S 903/952 : Housing details

Abstract

A hybrid transfer case includes a mainshaft, front and rear output shafts, an electric motor/generator connected to the mainshaft, and an input clutch for selectively coupling the transmission to the mainshaft. The transfer case further includes a planetary gearset having a sun gear driven by the mainshaft, a ring gear, and planet gears supported from a carrier. The carrier drives the rear output shaft and a transfer assembly couple to the front output shaft. A direct clutch is operable to selectively coupled the carrier for rotation with the mainshaft. A low brake is operable to selectively brake rotation of the ring gear. A transfer clutch controls the amount of drive torque delivered through the transfer assembly to the front output shaft. A hybrid control system is provided for controlling actuation of the various clutch and brake assemblies and the electric motor/generator to establish various drive modes.

Claims

1. A transfer case for use in a motor vehicle having an engine and first and second drivelines, comprising:

an input shaft adapted to be driven by the engine;

a mainshaft;

an input clutch for selectively coupling said input shaft to said mainshaft;

a first output shaft adapted for connection to the first driveline;

a second output shaft adapted for connection to the second driveline;

a planetary gearset having a sun gear driven by said mainshaft, a ring gear, and planet gears rotatably supported from a carrier and which are meshed with said sun gear and said ring gear, said carrier operably connected to said first output shaft and a transfer assembly;

a direct clutch for selectively coupling said mainshaft to said carrier;

a low brake for selectively braking rotation of said ring gear;

a transfer clutch for transferring drive torque from said transfer assembly to said second output shaft; and

an electric motor for selectively driving said mainshaft

2. The transfer case of claim 1 wherein said input clutch is operable in a released state to release said mainshaft from driven engagement with said input shaft and is further operable in an applied state to couple said mainshaft for rotation with said input shaft, wherein said direct clutch is operable in a released state to permit relative rotation between said carrier and said mainshaft and is further operable in an applied state to couple said carrier for rotation with said mainshaft, and wherein said low brake is operable in a released state to permit rotation of said ring gear and is further operable in an applied state to brake said ring gear against rotation.

3. The transfer case of claim 2 wherein a high-range drive connection is established between said mainshaft and said carrier when said direct clutch is operating in its applied state and said low brake is in its released state, and wherein a low-range drive connection is established between said mainshaft and said carrier when said direct clutch is in its released state and said low brake is in its applied state.

4. The transfer case of claim 3 wherein said transfer clutch is operable in a released state such that all drive torque is transferred from said carrier to said first output shaft to define a two-wheel drive mode, said transfer clutch is further operable in an applied state such that drive torque is transferred from said carrier to both of said first and second output shafts to define a four-wheel drive mode.

5. The transfer case of claim 4 wherein an electric two-wheel high-range drive mode is established when said input clutch is released, said direct clutch is applied, low brake is released, said transfer clutch is released and said electric motor is actuated to drive said mainshaft.

6. The transfer case of claim 4 wherein a hybrid two-wheel high-range drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released and said transfer clutch is released such that drive torque generated by said electric motor is combined with drive torque from the engine to drive said mainshaft.

7. The transfer case of claim 4 wherein an engine two-wheel high-range drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released, said transfer clutch is released and said electric motor is off such that drive torque generated by the engine drives said mainshaft.

8. The transfer case of claim 4 wherein an electric two-wheel low-range drive mode is established when said input clutch is released, said direct clutch is released, said low brake is applied, said transfer clutch is released and said electric motor is activated to drive said mainshaft.

9. The transfer case of claim 4 wherein a hybrid two-wheel low-range drive mode is established when said input clutch is applied, said direct clutch is released, said low brake is applied and said transfer clutch is released such that drive torque generated by said electric motor is combined with drive torque from the engine to drive said mainshaft.

10. The transfer case of claim 4 wherein an engine two-wheel low-range drive mode is established when said input clutch is applied, said direct clutch is released, said low brake is applied, said transfer clutch is released and said electric motor is off such that drive torque generated by the engine drives said mainshaft.

11. The transfer case of claim 4 wherein an electric four-wheel high-range drive mode is established when said input clutch is released, said direct clutch is applied, said low brake is released, said transfer clutch is applied and said electric motor is activated to drive said mainshaft.

12. The transfer case of claim 11 wherein said transfer clutch can be fully engaged to define a locked four-wheel high-range drive mode or actuation of said transfer clutch can be varied to define an on-demand four-wheel high-range drive mode.

13. The transfer case of claim 4 wherein a hybrid four-wheel high-range drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released, said transfer clutch is applied and drive torque generated by said electric motor is combined with drive torque from the engine to drive said mainshaft.

14. The transfer case of claim 13 wherein said transfer clutch can be fully engaged to define a locked four-wheel high-range drive mode or actuation of said transfer clutch can be varied to define an on-demand four-wheel high-range drive mode.

15. The transfer case of claim 4 wherein an engine four-wheel high-range drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released, said transfer clutch is applied and said electric motor is off such that drive torque generated by the engine drives said mainshaft.

16. The transfer case of claim 15 wherein said transfer clutch can be fully engaged to define a locked four-wheel high-range drive mode or actuation of said transfer clutch can be varied to define an on-demand four-wheel high-range drive mode.

17. The transfer case of claim 4 wherein said input clutch is a spring-apply multi-plate clutch assembly operable disposed between said input shaft and said mainshaft, said input clutch is normally operable in its applied state and can be selectively shifted into its released state via actuation of a first power-operated actuator controlled by a control system.

18. The transfer case of claim 17 wherein said direct clutch is a spring-apply multi-plate clutch assembly operably disposed between said mainshaft and said carrier, said direct clutch is normally operable in its applied state and can be selectively shifted into its released state via actuation of a second power-operated actuator controlled by said control system.

19. The transfer case of claim 18 wherein said low brake is a spring-release multi-plate brake assembly operably disposed between said ring gear and a stationary member, said low brake is normally operable in its released state and can be selectively shifted into its applied state via actuation of said second power-operated actuator.

20. The transfer case of claim 19 wherein said transfer clutch is a spring-released multi-plate clutch assembly operably disposed between said transfer assembly and said second output shaft, said transfer clutch is normally operable in its released state and can be selectively shifted into its applied state via actuation of a third power-operated actuator.

21. The transfer case of claim 20 wherein said control system includes a controller and sensors for detecting operating characteristics of the vehicle and sending sensor signals to said controller, said controller operable to send control signals to said electric motor and said first, second and third actuators.

22. A transfer case for use in a motor vehicle having an engine and first and second drivelines, comprising:

an input shaft adapted to be driven by the engine;

a mainshaft;

an input clutch for selectively coupling said shaft to said mainshaft;

a first output shaft adapted for connection to the first driveline;

a second output shaft adapted for connection to the second driveline;

a planetary gearset having a sun gear driven by said mainshaft, a ring gear, and planet gears rotatably supported from a carrier and meshed with said sun gear and said ring gear, said carrier operably connected to said first output shaft and a transfer assembly;

a direct clutch for selectively coupling said mainshaft to said carrier;

a low brake for selectively braking rotation of said ring gear;

a transfer clutch for transferring drive torque from said transfer assembly to said second output shaft;

an electric motor for selectively driving said mainshaft; and

a control system for controlling actuation of said input clutch, said direct clutch, said low brake and said electric motor.

23. The transfer case of claim 22 wherein said control system is further operable to control actuation of said transfer clutch.

24. The transfer case of claim 22 wherein said electric motor includes a stator secured to a housing and a rotor secured to said mainshaft.

25. The transfer case of claim 22 wherein said carrier includes a first member fixed to said first output shaft and a second member defining a clutch drum, said direct clutch including a hub fixed to said mainshaft, and a clutch pack disposed between said clutch drum and hub.

26. The transfer case of claim 22 further comprising:

a valvebody supporting a first electrohydraulic control valve controlling actuation of said input clutch, a second electrohydraulic control valve controlling actuation of said direct clutch, and a third electrohydraulic control valve controlling actuation of said low brake; and

a hydraulic circuit providing high pressure fluid to said first, second and third control valves.

27. A hybrid motor vehicle, comprising:

a powertrain including an internal combustion engine and a transmission;

a first driveline including a first axle driving a pair of first wheels;

a second driveline including a second axle driving a pair of second wheels;

a transfer case including an input shaft driven by said powertrain, a mainshaft, an input clutch for selectively coupling said input shaft to said mainshaft, a first output shaft operably connected to said first driveline, a second output shaft operably connected to said second driveline, a planetary reduction unit having a sun gear driven by said mainshaft, a ring gear and planet gears meshed with said sun and ring gears, said planet gears rotatably supported from a carrier which is fixed to said first output shaft, a transfer unit driven by said carrier, a direct clutch for selectively coupling said mainshaft to said carrier, a low brake for selectively braking rotation of said ring gear, a transfer clutch for selectively transferring drive torque from said transfer unit to said second output shaft, and an electric motor for driving said mainshaft; and

a control system for controlling actuation of said input clutch, said direct clutch, said low brake and said electric motor for defining an electric drive mode, a hybrid drive mode and a powertrain drive mode.

28. The hybrid motor vehicle of claim 27 wherein said input clutch is operable in a released state to release said mainshaft from driven engagement with said input shaft and is further operable in an applied state to couple said mainshaft for rotation with said input shaft, wherein said direct clutch is operable in a released state to permit relative rotation between said carrier and said mainshaft and is further operable in an applied state to couple said carrier for rotation with said mainshaft, and wherein said low brake is operable in a released state to permit rotation of said ring gear and is further operable in an applied state to brake said ring gear against rotation.

29. The hybrid motor vehicle of claim 28 wherein a high-range drive connection is established between said mainshaft and said carrier when said direct clutch is operating in its applied state and said low brake is in its released state, and wherein a low-range drive connection is established between said mainshaft and said carrier when said direct clutch is in its released state and said low brake is in its applied state.

30. The hybrid motor vehicle of claim 29 wherein said transfer clutch is operable in a released state such that all drive torque is transferred from said carrier to said first output shaft to define a two-wheel drive mode, said transfer clutch is further operable in an applied state such that drive torque is transferred from said carrier to both of said first and second output shafts to define a four-wheel drive mode.

31. The hybrid motor vehicle of claim 30 wherein an electric two-wheel high-range drive mode is established when said input clutch is released, said direct clutch is applied, said low brake is released, said transfer clutch is released and said electric motor is actuated to drive said mainshaft.

32. The hybrid motor vehicle of claim 30 wherein a hybrid two-wheel high-range drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released, said transfer clutch is released and drive torque generated by said electric motor is combined with drive torque from the engine to drive said mainshaft.

33. The hybrid motor vehicle of claim 30 wherein an engine two-wheel high-range drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released, said transfer clutch is released and said electric motor is off such that drive torque generated by the engine drives said mainshaft.

34. The hybrid motor vehicle of claim 30 wherein an electric two-wheel low-range drive mode is established when said input clutch is released, said direct clutch is released, said low brake is applied, said transfer clutch is released and said electric motor is activated to drive said mainshaft.

35. The hybrid motor vehicle of claim 30 wherein a hybrid two-wheel low-range drive mode is established when said input clutch is applied, said direct clutch is released, said low brake is applied, said transfer clutch is released and drive torque generated by said electric motor is combined with drive torque from the engine to drive said mainshaft.

36. The hybrid motor vehicle of claim 30 wherein an engine two-wheel low-range drive mode is established when said input clutch is applied, said direct clutch is released, said low brake is applied, said transfer clutch is released and said electric motor is off such that drive torque generated by the engine drives said mainshaft.

37. The hybrid motor vehicle of claim 30 wherein an electric four-wheel high-grade drive mode is established when said input clutch is released, said direct clutch is applied, said low brake is released, said transfer clutch is applied and said electric motor is activated to drive said mainshaft.

38. The hybrid motor vehicle of claim 37 wherein said transfer clutch can be fully engaged to define a locked four-wheel high-range drive mode or actuation of said transfer clutch can be varied to define an on-demand four-wheel high-range drive mode.

39. The hybrid motor vehicle of claim 30 wherein a hybrid four-wheel high-grade drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released, said transfer clutch is applied and drive torque generated by said electric motor is combined with drive torque from the engine to drive said mainshaft.

40. The hybrid motor vehicle of claim 39 wherein said transfer clutch can be fully engaged to define a locked four-wheel high-range drive mode or actuation of said transfer clutch can be varied to define an on-demand four-wheel high-range drive mode.

41. The hybrid motor vehicle of claim 30 wherein an engine four-wheel high-grade drive mode is established when said input clutch is applied, said direct clutch is applied, said low brake is released, said transfer clutch is applied and said electric motor is off such that drive torque generated by the engine drives said mainshaft.

42. The hybrid motor vehicle of claim 41 wherein said transfer clutch can be fully engaged to define a locked four-wheel high-range drive mode or actuation of said transfer clutch can be varied to define an on-demand four-wheel high-range drive mode.