Electric drive axle for hybrid vehicle

• US 6,401,850 B1
• Filed: 03/14/2001
• Issued: 06/11/2002
• Est. Priority Date: 03/14/2001
• Status: Expired due to Term

• Current Assignee: New Venture Gear, Incorporated (Magna International Incorporated)
• Original Assignee: New Venture Gear, Incorporated (Magna International Incorporated)
• Inventors: Bowen, Thomas C.
• Primary Examiner(s): Butler, Douglas C.
• Application Number:
  US09/808,575
• Time in Patent Office: 454 Days
• Field of Search: 180/65.6, 180/165, 180/65.2, 180/69.6, 180/65.4, 180/65.7, 475/2, 475/3, 475/5, 475/149, 475/150, 475/151, 475/206, 475/174, 477/2, 607/18, 701/22, 746/61, 743/35, 318/376
• US Class Current: 180/65.6
• CPC Class Codes: B60K 1/00 Arrangement or mounting of electrical propulsion units B60K7/00 takes precedence; arrangement or mounting of plural diverse prime-movers for mutual or common propulsion B60K6/00; electric transmission arrangements B60K17/12; electric equipment or propulsion of electrically-propelled vehicles per se B60L; current-collectors for power supply lines of electrically-propelled vehicles B60L5/00
• CPC Class Codes: B60K 17/04 characterised by arrangement, location, or kind of gearing electric equipment or propulsion of electrically-propelled vehicles B60L
• CPC Class Codes: B60K 17/16 of differential gearing
• 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 2001/001 one motor mounted on a propulsion axle for rotating right and left wheels of this axle
• 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 6/40 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 1/28 with gears having orbital motion
• CPC Class Codes: F16H 37/082 and additional planetary reduction gears
• CPC Class Codes: F16H 48/08 comprising bevel 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

An electric drive axle for use in hybrid vehicles has an electric motor driving a compact gearbox. The gearbox includes a planetary reduction unit and a differential assembly. The planetary reduction unit has compound planet gears supported from a planet carrier which mesh with a fixed ring gear and a sun gear driven by the electric motor. The planet carrier drives the differential which transfer motive power to a pair of output shafts adapted for connection to one set of wheels. When used with a conventional engine-based powertrain for the other set of wheels, the electric drive axle establishes a four-wheel drive powertrain for the hybrid vehicle. The electric motor and gearbox are mounted in a common housing assembly to provide a compact drive axle assembly.

Claims

1. A drive axle for a motor vehicle, comprising:

a housing defining first and second chambers;

an electric motor disposed in said first chamber and having a rotor shaft extending into said second chamber; and

a gearbox disposed in said second chamber and operably coupling said rotor shaft to first and second output shafts, said gearbox including a planetary reduction gearset having a ring gear fixed to said housing, a sun gear driven by said rotor shaft, a planet carrier, and compound planet gears rotatably supported by said planet carrier and having a first gear segment meshed with said sun gear and a second gear segment meshed with said ring gear, said gearbox further including a differential assembly having an input member driven by said planet carrier, a first output member driving said first output shaft, and a second output member driving said second output shaft.

2. The drive axle of claim 1 wherein said rotor shaft is tubular and is rotatably supported on said second output shaft.

3. The drive axle of claim 1 wherein said differential assembly is a bevel gearset having a differential casing fixed for rotation with said planet carrier, a first side gear fixed for rotation with said first output shaft, a second side gear fixed for rotation with said second output shaft, and pinions rotatably supported by said casing and meshed with said first and second side gears.

4. The drive axle of claim 3 wherein said planet carrier includes a first ring offset from and interconnected to a second ring with said compound planet gears rotatably supported on pins extending between said first and second rings.

5. The drive axle of claim 4 wherein said differential casing includes a radial plate segment fixedly secured to said second ring of said planet carrier.

6. The drive axle of claim 4 wherein said second ring of said planet carrier is integral with said differential case.

7. The drive axle of claim 1 wherein said differential assembly is a planetary gearset having a second ring gear fixed for rotation with said planet carrier, an output sun gear fixed for rotation with said first output shaft, an output carrier fixed for rotation with said second output shaft, a first pinion rotatably supported by said output carrier and meshed with said second ring gear, and a second pinion rotatably supported by said output carrier and meshed with said first pinion and said output sun gear.

8. The drive axle of claim 1 wherein said first and second output shafts are adapted for connection to a pair of first wheels to deliver drive torque thereto in response to actuation of said electric motor.

9. The drive axle of claim 8 wherein said first wheels are front wheels of the motor vehicle.

10. The drive axle of claim 9 wherein the motor vehicle has rear wheels driven by power from an engine.

11. The drive axle of claim 8 wherein said first wheels are rear wheels of the motor vehicle.

12. The drive axle of claim 11 wherein the motor vehicle has front wheels driven by power from an engine.

13. An electrically-powered drive axle for driving a pair of wheels in a motor vehicle, comprising:

a housing;

first and second output shafts rotatably supported by said housing and adapted for connection to the pair of wheels;

an electric motor assembly disposed in said housing and having a rotor shaft; and

a gearbox disposed in said housing and including a planetary reduction gearset and a bevel differential, said planetary reduction gearset having a sun gear driven by said rotor shaft, a ring gear non-rotatably secured to said housing, a planet carrier, and a plurality of compound planet gears rotatably supported by said planet carrier and having a first gear segment meshed with said sun gear and a second gear segment meshed with said ring gear, said bevel differential having a casing driven by said planet carrier, a first side gear fixed for rotation with said first output shaft, a second side gear fixed for rotation with said second output shaft, and pinions rotatably supported by said casing and meshed with said first and second side gears.

14. The drive axle of claim 13 wherein said rotor shaft is tubular and is rotatably supported on said second output shaft.

15. The drive axle of claim 13 wherein said planet carrier includes a first ring offset from and interconnected to a second ring with said compound planet gears rotatably supported on pins extending between said first and second rings.

16. The drive axle of claim 15 wherein said differential casing includes a radial plate segment fixedly secured to said second ring of said planet carrier.

17. The drive axle of claim 15 wherein said second ring of said planet carrier is integral with said differential case.

18. The drive axle of claim 13 further comprising:

vehicle sensors for detecting operating characteristics of the motor vehicle and generating sensor signals; and

a controller for generating electrical control signals in response to said sensor signals, said control signals being delivered to said motor assembly for controlling the rotary speed of said rotor shaft.

19. An electrically-powered drive axle for driving a pair of wheels in a motor vehicle, comprising:

a housing;

first and second output shafts rotatably supported by said housing and adapted for connection to the pair of wheels;

an electric motor assembly disposed in said housing and having a rotor shaft; and

a gearbox disposed in said housing and having a first sun gear driven by said rotor shaft, a first ring gear fixed to said housing, a first carrier, and compound planet gears rotatably supported by said first carrier and having a first gear segment meshed with said first sun gear and a second segment meshed with said first ring gear, said gearbox also including a second ring gear driven by said first carrier, a second sun gear fixed for rotation with said first output shaft, a second carrier fixed for rotation with said second output shaft, a set of first pinions rotatably supported by said second carrier and meshed with said second ring gear, and a set of second pinions rotatably supported by said second carrier and meshed with said second sun gear and said first pinions.

20. The drive axle of claim 19 wherein said rotor shaft is tubular and is rotatably supported on said second output shaft.

21. The drive axle of claim 19 further comprising:

vehicle sensors for detecting operating characteristics of the motor vehicle and generating sensor signals; and

a controller for generating electrical control signals in response to said sensor signals, said control signals being delivered to said motor assembly for controlling the rotary speed of said rotor shaft.

22. A hybrid motor vehicle, comprising:

a first powered driveline including an engine operable for driving a first pair of wheels; and

a second powered driveline including a drive axle operable for driving a second pair of wheels, said drive axle including a housing, an electric motor located in said housing and having a rotor shaft, and a gearbox located in said housing and having a reduction gearset and a differential, said reduction gearset having a sun gear driven by said rotor shaft, a ring gear fixed to said housing, a planet carrier, and compound planet gears supported by said planet carrier and having a first gear segment meshed with said sun gear and a second gear segment meshed with said ring gear, said differential having an input member driven by said planet carrier and first and second output members driving said second pair of wheels.

23. The hybrid motor vehicle of claim 22 wherein said drive axle further includes a first output shaft coupled to said first output member and a second output shaft coupled to said second output member, and wherein said rotor shaft is tubular and rotatably supported on said second output shaft.

24. The hybrid motor vehicle of claim 23 wherein said differential is a bevel gearset having a casing fixed for rotation with said planet carrier, a first side gear fixed for rotation with said first output shaft, a second side gear fixed for rotation with said second output shaft, and pinions rotatably supported by said casing and meshed with said first and second side gears.

25. The hybrid motor vehicle of claim 23 wherein said differential is a planetary gearset having a second ring gear fixed for rotation with said planet carrier, an output sun gear fixed for rotation with said first output shaft, an output carrier fixed for rotation with said second output shaft, a first pinion rotatably supported by said output carrier and meshed with said second ring gear, and a second pinion supported by said output carrier and meshed with said first pinion and said output sun gear.

26. The hybrid motor vehicle of claim 22 further comprising:

vehicle sensors for detecting operating characteristics of the motor vehicle and generating sensor signals; and

a controller for generating electrical control signals in response to said sensor signals, said control signals being delivered to said motor assembly for controlling the rotary speed of said rotor shaft.