Transfer case for hybrid vehicle

• US 6,533,693 B2
• Filed: 06/20/2002
• Issued: 03/18/2003
• Est. Priority Date: 02/08/2001
• Status: Active Grant

• Current Assignee: New Venture Gear, Incorporated (Magna International Incorporated)
• Original Assignee: New Venture Gear, Incorporated (Magna International Incorporated)
• Inventors: Mohan, Sankar K., Bowen, Thomas C.
• Primary Examiner(s): Estremsky, Sherry
• Assistant Examiner(s): Lewis, Tisha D.
• Application Number:
  US10/175,622
• Publication Number:
  US 20020160874A1
• Time in Patent Office: 271 Days
• Field of Search: 180/65.2, 180/65.4, 180/242, 180/244, 180/65.3, 475/5, 475/4, 475/6, 477/4, 477/9, 477/5
• US Class Current: 475/5
• CPC Class Codes: B60K 17/346 the transfer gear being a differential gear
• 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 2006/4833 Step up or reduction gearing driving generator, e.g. to operate generator in most efficient speed range
• 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 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/40 characterised by the assembly or relative disposition of components
• 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: F16H 2200/2007 with two sets of orbital gears
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/91 Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/916 with plurality of drive axles
• CPC Class Codes: Y10S 903/951 Assembly or relative location of components

Abstract

A hybrid drive system for a four-wheel drive system arranged to supply motive power to a transfer case from an internal combustion engine and/or an electric motor/generator. The transfer case is comprised of a planetary gearset having a first input driven by the motor/generator, a second input driven by the engine, and an output directing drive torque to the front and rear drivelines. The output of the planetary gearset drives a rear output shaft connected to the rear driveline and further drives a front output shaft connected to the front driveline. The transfer case further includes a second planetary gearset having an input driven by the motor/generator and an output driving the first input of the first planetary gearset. This hybrid drive arrangement permits use of a modified transfer case in place of a conventional transfer case in a traditional four-wheel drive driveline.

Claims

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

an input member adapted to be driven by the engine;

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

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

an input clutch operable in an engaged mode to couple said first output member for rotation with said input member and in a released mode to uncouple said first output member from said input member;

a gearset coupled to said first output member;

an electric motor for selectively driving said gearset;

an input brake operable in a released mode to permit rotation of said input member and in an engaged mode to brake said input member against rotation; and

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

2. The transfer case of claim 1 wherein said control system controls coordinated actuation of said input clutch, said input brake and said electric motor to define an electric operating mode, a hybrid operating mode, and an engine operating mode.

3. The transfer case of claim 1 wherein said input clutch includes a clutch pack connected between said input member and said first output member, an apply plate, and a power-operated clutch actuator which is controlled by said control system for selectively moving said apply plate to exert a clutch engagement force on said clutch pack for shifting said input clutch between its released and engaged modes.

4. The transfer case of claim 1 wherein said gearset includes a sun gear, a ring gear fixed to said input member, and pinion gears meshed with said ring gear and said sun gear, said pinion gears are rotatably supported on a pinion carrier that is coupled to said first output member, and wherein said electric motor is selectively actuated for driving said sun gear.

5. The transfer case of claim 1 further comprising a transfer mechanism for transferring drive torque to said second output member from one of said input member and said first output member.

6. The transfer case of claim 2 wherein said electric operating mode is established with said input clutch in its released mode, said input brake in its engaged mode and said electric motor actuated for driving said gearset.

7. The transfer case of claim 2 wherein said engine operating mode is established with said input clutch in its engaged mode, said input brake in its released mode and said electric motor turned off.

8. The transfer case of claim 2 wherein said hybrid operating mode is established with said input clutch in its engaged mode, said input brake in its released mode and said electric motor actuated for driving said gearset.

9. The transfer case of claim 3 wherein said input brake includes a band brake located adjacent to said input member and a power-operated brake actuator which is controlled by said control system for selectively moving band brake to exert a braking force on said input member for shifting said input brake between its released and engaged modes.

10. The transfer case of claim 9 wherein said control system includes a controller and sensors for detecting operating characteristics of the vehicle and sending sensor input signals to said controller, and wherein said controller is operable to send control signals to said electric motor, said clutch actuator and said brake actuator.

11. The transfer case of claim 4 wherein said gearset further includes a second sun gear driven by said electric motor, a non-rotational second ring gear, and planet gears meshed with said second sun gear and said second ring gear, said planet gears are rotatably supported from a planet carrier which is coupled to said first sun gear.

12. The transfer case of claim 5 wherein said transfer mechanism includes a first sprocket driven by said gearset, a second sprocket supported on said second output member, a power chain connecting said first and second sprockets, and a transfer clutch operable in a released mode to permit rotation of said second sprocket relative to said second output member and in an engaged mode to rotatively couple said second output member to said second sprocket.

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

an input member adapted to be driven by the engine;

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

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

an input clutch operable in an engaged mode to rotatively couple said first output shaft to said input member and in a released mode to release said first output shaft from engagement with said input member;

an input brake operable in a released mode to permit rotation of said input member and in an engaged mode to brake said input member against rotation;

a gearset coupled to said first output shaft; and

an electric motor for selectively driving said gearset.

14. The transfer case of claim 13 further comprising a control system for controlling actuation of said input clutch, said input brake and said electric motor to define an electric operating mode, a hybrid operating mode, and an engine operating mode.

15. The transfer case of claim 13 wherein said gearset includes a sun gear, a ring gear fixed to said input member, and pinion gears meshed with said ring gear and said sun gear, said pinion gears are rotatably supported on a pinion carrier that is coupled to said first output member, and wherein said electric motor is selectively actuated to drive said sun gear.

16. The transfer case of claim 13 wherein said input clutch includes a clutch pack connected between said input member and said first output shaft, an apply plate, and a power-operated clutch actuator for selectively moving said apply plate to exert a clutch engagement force on said clutch pack for shifting said input clutch between its released and engaged modes.

17. The transfer case of claim 13 further comprising a transfer mechanism for transferring drive torque to said second output shaft from one of said input member and said first output shaft.

18. The transfer case of claim 14 wherein said electric operating mode is established with said input clutch in its released mode, said input brake in its engaged mode and said electric motor is actuated for driving said gearset.

19. The transfer case of claim 14 wherein said hybrid operating mode is established with said input clutch in its engaged mode, said input brake in its released mode and said electric motor is actuated for driving said gearset.

20. The transfer case of claim 14 wherein said engine operating mode is established with said input clutch in its engaged mode, said input brake in its released mode and said electric motor turned off.

21. The transfer case of claim 15 wherein said gearset further includes a second sun gear driven by said electric motor, a non-rotational second ring gear, and planet gears meshed with said second sun gear and said second ring gear, said planet gears are rotatably supported from a planet carrier which is coupled to said first sun gear.

22. The transfer case of claim 16 wherein said input brake includes a band brake located adjacent to said input member and a power-operated brake actuator for selectively moving said band brake to exert a braking force on said input member for shifting said input brake between its released and engaged modes.

23. The transfer case of claim 22 further comprising a control system having a controller and sensors for detecting operating characteristics of the vehicle and sending sensor input signals to said controller, said controller operable to send control signals to said electric motor, said clutch actuator and said brake actuator.

24. The transfer case of claim 17 wherein said transfer mechanism includes a first sprocket driven by said gearset, a second sprocket supported on said second output shaft, a power chain connecting said first and second sprockets, and a transfer clutch operable in a released mode to permit rotation of said second sprocket relative to said second output shaft and in an engaged mode to rotatively couple said second output shaft to said second sprocket.

25. A hybrid vehicle comprising:

a powertrain including an engine and a transmission;

a first driveline including a first differential connecting a first pair of wheels;

a second driveline including a second differential connecting a second pair of wheels;

a transfer case including an input member driven by said powertrain, a first output member operably connected to said first differential, a second output member operably connected to said second differential, an input clutch operable in an engaged mode to couple said first output member to said input member and in a released mode to release said first output member from said input member, an input brake operable in a released mode to permit rotation of said input member and in an engaged mode to brake rotation of said input member, a gearset coupled to said first output member, and an electric motor for selectively driving said gearset; and

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

26. The hybrid motor vehicle of claim 25 wherein said transfer case further includes a transfer mechanism for coupling said second output member to one of said gearset and said first output member.

27. The hybrid motor vehicle of claim 25 wherein said control system controls said input clutch, said input brake, and said electric motor to define an electric operating mode, a hybrid operating mode, and an engine operating mode.

28. The hybrid motor vehicle of claim 25 wherein said gearset includes a first planetary gearset having a sun gear, a ring gear fixed to said input member, and pinion gears meshed with said ring gear and said sun gear, said pinion gears rotatably supported on a pinion carrier.

29. The transfer case of claim 27 wherein said electric operating mode is established with said input clutch in its released mode, said input brake in its engaged mode and said electric motor is actuated for driving said gearset.

30. The transfer case of claim 27 wherein said hybrid operating mode is established with said input clutch in its engaged mode, said input brake in its released mode and said electric motor is actuated for driving said gearset.

31. The transfer case of claim 27 wherein said engine operating mode is established with said input clutch in its engaged mode, said input brake in its released mode and said electric motor turned off.

32. The hybrid motor vehicle of claim 28 wherein said gearset further comprises a second planetary gearset having a second sun gear driven by said electric motor, a non-rotational second ring gear, and planet gears meshed with said second sun gear and second ring gear, said planet gears rotatably supported from a planet carrier fixed to said first sun gear.

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

an input member adapted to be driven by the engine;

a first output member adapted for connection to the first driveline

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

an input brake operable in an engaged mode to brake rotation of said input member and in a released mode to permit rotation of said input member;

a gearset coupled to said first output member;

an electric motor for selectively driving said gearset; and

a control system for controlling actuation of said input brake and said electric motor.

34. The transfer case of claim 33 wherein said control system includes a controller and sensors for detecting operating characteristics of the vehicle and sending sensor input signals to said controller, and wherein said controller is operable to send control signals to said electric motor and said brake actuator.

35. A hybrid vehicle comprising:

a powertrain including an engine and a transmission;

a first driveline including a first differential connecting first pair of wheels;

a second driveline including a second differential connecting a second pair of wheels;

a transfer case including an input member driven by said powertrain, a first output member operably connected to said first differential, a second output member operably connected to said second differential, an input brake operable in an engaged mode to brake rotation of said input member and in a released mode to permit rotation of said input member, a gearset coupled to said first output member, and an electric motor for selectively driving said gearset; and

a control system for controlling actuation of said input brake and said electric motor.

36. The transfer case of claim 35 wherein said control system includes a controller and sensors for detecting operating characteristics of the vehicle and sending sensor input signals to said controller, and wherein said controller is operable to send control signals to said electric motor and said brake actuator.