Hybrid four-wheel-drive

• US 20060108166A1
• Filed: 11/07/2005
• Published: 05/25/2006
• Est. Priority Date: 11/08/2004
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Tanaka, Daiki, Sugihara, Jun
• Granted Patent: US 7,467,678 B2
• Time in Patent Office: Days
• US Class Current: 180/248
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• 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 28/16 responsive to, or preventing, skidding of wheels brake control systems for vehicle drive stability B60T8/1755; arrangements responsive to a speed condition for adjusting wheel braking force B60T8/32; control of vehicle driving stability otherwise than by controlling the propulsion unit only B60W30/02; preventing wheel slippage by reducing power in rail vehicles B61C15/00
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution 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: 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 10/115 with planetary gears
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2300/18 Four-wheel drive vehicles
• CPC Class Codes: B60W 2520/263 Slip values between front and rear axle
• CPC Class Codes: F16H 2037/103 Power split variators with each end of the CVT connected or connectable to a Ravigneaux set
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/93 Conjoint control of different elements

Abstract

A four-wheel drive system for a hybrid vehicle includes at least two motor-generators and a single engine connected to a differential having multiple degrees of freedom. In some embodiments, by adjusting the outputs of the motor-generators, a controller allocates power from the engine, to or from each of the motor-generators, to the front wheels and to the rear wheels, each of which is connected to an element of the differential. The relationship between the elements of the differential is represented by an alignment chart of the differential.

Claims

1. A drivetrain for a vehicle comprising:

a first driveline system that includes one of front wheels or rear wheels;

a second driveline system that includes the other of the front wheels and the rear wheels;

a differential gear mechanism including,

a first rotational element that receives power from an engine and outputs power to the first driveline system,

a second rotational element that inputs power from a first motor-generator, and

a third rotational element that inputs power from a second motor-generator, wherein a rotational element of the differential gear mechanism other than the first rotational element outputs power to the second driveline system; and

a controller to adjust power outputs to the first driveline system and the second driveline system.

2. The drivetrain of claim 1, wherein the controller adjusts power outputs to the first driveline system and the second driveline system by adjusting power output of the engine, power output of the first motor-generator, and power output of the second motor-generator.

3. The drivetrain of claim 1, wherein the first driveline system includes a transmission.

4. The drivetrain of claim 3, wherein the first driveline system includes rear wheels and the transmission is located near a rear axle corresponding to the rear wheels.

5. The drivetrain of claim 3, wherein the controller reduces power output to the first driveline system when gear shifts take place in the transmission without changing power output to the second driveline system.

6. The drivetrain of claim 1, wherein the rotational element of the differential gear mechanism that outputs power to the second driveline system is one of a group consisting of:

the second rotational element; and

the third rotational element.

7. The drivetrain of claim 1, wherein the rotational elements of the differential gear mechanism are aligned on an alignment chart.

8. The drivetrain of claim 1, wherein the first driveline system includes the front wheels and the second driveline system includes the rear wheels.

9. The drivetrain of claim 1, wherein the controller receives an input representing a slippage ratio of front and rear wheels and adjusts power output to the motor-generator according to the slippage ratio.

10. The drivetrain of claim 1, wherein the controller adjusts first and second motor-generators to increase or decrease power output from the engine to the differential gear without changing a power output from the differential gear, wherein the power output from the differential gear mechanism includes the power outputs to the first and second driveline systems.

11. The drivetrain of claim 1, wherein the controller adjusts first and second motor-generators to increase or decrease a power output from the differential gear mechanism without changing power output from the engine to the differential gear.

12. The drivetrain of claim 1, wherein the differential gear mechanism further includes a clutch connected to the first element.

13. The drivetrain of claim 1, wherein the differential gear mechanism drives a pump that generates an oil pressure source.

14. The drivetrain of claim 1, wherein the controller operates the first and second motor-generators to control the distribution of power output to the front and rear wheels based on data from an acceleration sensor in the vehicle.

15. The drivetrain of claim 1, wherein the third rotational element outputs power to the second driveline system.

16. The drivetrain of claim 15, wherein rotational elements are in the following order on an alignment chart:

the second rotational element,

the first rotational element, and

the third rotational element.

17. The drivetrain of claim 1, wherein the rotational element of the differential gear mechanism that outputs power to the second driveline system is a fourth rotational element.

18. The drivetrain of claim 17, wherein rotational elements are in the following order on an alignment chart:

the second rotational element,

the first rotational element,

the fourth rotational element, and

the third rotational element.

19. The drivetrain of claim 17, wherein the differential gear mechanism further includes:

a housing member, and

a fifth rotational element, wherein the fifth rotational element is connected to the housing member.

20. The drivetrain of claim 1, wherein the controller can selectively allocate drive power among the first driveline system and the second driveline system at any ratio between 0:

100 and 100;

0 inclusive.

21. The drivetrain of claim 1, wherein the first driveline system and the second driveline system input power to the differential gear mechanism, and the controller transfers the input power to one or more of the motor-generators during regenerative braking of the vehicle.

22. The drivetrain of claim 1, wherein the differential gear mechanism is a planetary gear mechanism.

23. A hybrid four-wheel-drive system comprising:

a front driveline system;

a rear driveline system;

a differential gear having at least two degrees of freedom, the differential gear including a power input from an engine, a power output for the rear driveline system, a power output for the front driveline system, a power input for a first motor generator and a power input for a second motor generator; and

a means for controlling the power input from the engine, the power output for the rear driveline system and the power output for the front driveline system.