Electric motor and gear drive assembly for driving a vehicle wheel

• US 20050023056A1
• Filed: 07/31/2003
• Published: 02/03/2005
• Est. Priority Date: 07/31/2003
• Status: Active Grant

• Current Assignee: ArvinMeritor Technology LLC (Meritor, Inc. (Nevada))
• Original Assignee: ArvinMeritor Technology LLC (Meritor, Inc. (Nevada))
• Inventors: Eschenburg, Dale J., Harrup, Clive, Kramer, Dennis A., Platner, David K., Bell, Dale K., House, Dean M., Yamada, Silvio M., Ciray, Mehmet S.
• Granted Patent: US 7,458,433 B2
• Time in Patent Office: Days
• US Class Current: 180/65.600
• CPC Class Codes: B60K 17/046 with planetary gearing having orbital motion
• 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 2007/0038 the motor moving together with the wheel axle
• CPC Class Codes: B60K 7/0007 the motor being electric
• CPC Class Codes: B60L 15/2054 by controlling transmissions or clutches
• CPC Class Codes: B60L 2220/46 Wheel motors, i.e. motor connected to only one wheel
• CPC Class Codes: B60L 50/60 using power supplied by batteries in combination with fuel cells B60L50/75
• 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 10/72 Electric energy management in electromobility
• CPC Class Codes: Y10S 903/906 Motor or generator

Abstract

A drive unit assembly for a vehicle wheel includes a rigidly mounted electric motor coupled to the vehicle wheel via a gear drive. The gear drive includes a cycloid or epicycloid gear arrangement that provides significant speed reduction at the wheel.

Claims

1. A drive unit assembly for a vehicle wheel comprising:

a wheel defining an axis of rotation;

a gear drive defining a gear drive axis and having at least a first gear component and a second gear component, said second gear component being driven by said first gear component and being directly coupled to said wheel to drive said wheel about said axis of rotation; and

an electric motor including a motor output shaft that is non-concentric with said gear drive axis wherein said motor output shaft is operably coupled to said gear drive to provide a driving input to said wheel.

2. An assembly as set forth in claim 1 wherein said motor output shaft rotates at a first rotational speed and said wheel rotates at a second rotational speed less than said first rotational speed.

3. An assembly as set forth in claim 2 wherein rotational speed reduction between said first rotational speed and said second rotational speed is a ratio of at least twenty to one.

4. An assembly as set forth in claim 2 wherein said electric motor includes a motor casing rigidly mounted to a vehicle suspension.

5. An assembly as set forth in claim 2 wherein said motor output shaft is coaxial with said axis of rotation.

6. An assembly as set forth in claim 2 wherein said gear drive comprises a cycloid gear reduction.

7. An assembly as set forth in claim 6 including an eccentric cam mounted for rotation with said motor output shaft, said eccentric cam defining said gear drive axis.

8. An assembly as set forth in claim 7 wherein said first gear component comprises a first cycloid member having a central bore for receiving and rotatably supporting said eccentric cam and a plurality of circumferential bores spaced radially about a circumference of said first cycloid member relative to said central bore and wherein said second gear component comprises a second cycloid member fixed to said wheel and including a plurality of drive members spaced about a circumference of said second cycloid member with each drive member being received in a corresponding one of said circumferential bores such that said eccentric cam drives said second cycloid member via said first cycloid member to achieve speed reduction at said wheel.

9. An assembly as set forth in claim 8 wherein said motor output shaft is non-concentric with said central bore and wherein each of said drive members is non-concentric with said respective circumferential bore.

10. An assembly as set forth in claim 2 wherein said gear drive comprises an epicycloid gear reduction.

11. An assembly as set forth in claim 10 wherein said first gear component comprises a non-rotating ring gear and said second gear component comprises a drive gear defining said gear drive axis and in driving engagement with said ring gear, said drive gear operably coupled to said motor output shaft to receive driving input and operably coupled to said wheel to provide driving output.

12. An assembly as set forth in claim 11 including a chain and sprocket drive interconnecting said motor output shaft and said drive gear.

13. A drive unit assembly for driving at least two laterally spaced wheels on opposing sides of a vehicle comprising:

a first wheel positioned on one side of a vehicle and defining a lateral axis of rotation;

a second wheel laterally spaced from said first wheel and positioned on an opposite side of the vehicle wherein said first and second wheels are mounted for rotation about said lateral axis of rotation;

a first gear drive defining a first gear drive axis and having at least a first gear component and a second gear component, said second gear component in driving engagement with said first gear component and operably coupled to said first wheel to drive said first wheel about said lateral axis of rotation;

a second gear drive defining a second gear drive axis and having at least a third gear component and a fourth gear component, said fourth gear component in driving engagement with said third gear component and operably coupled to said second wheel to drive said second wheel about said lateral axis of rotation; and

at least one electric motor output having a motor output that is non-concentric with said first and second gear drive axes wherein said motor output is operably coupled to said first and second gear drives to provide a driving input to said first and second wheels.

14. An assembly as set forth in claim 13 wherein said at least one electric motor comprises a single electric motor for driving both said first and second wheels said single electric motor including a first motor output shaft that is non-concentric with said first gear drive axis and a second motor output shaft that is non-concentric with said second gear drive axis, said first motor output shaft in driving engagement with said first gear component and said second motor output shaft in driving engagement with said third gear component.

15. An assembly as set forth in claim 13 wherein said at least one electric motor comprises at first electric motor for driving said first wheel and a second electric motor for driving said second wheel independently from said first wheel, said first electric motor including a first motor output shaft that is non-concentric with said first gear drive axis and said second electric motor including a second motor output shaft that is non-concentric with said second gear drive axis.

16. An assembly as set forth in claim 13 including at least one suspension component mounted to a non-rotating vehicle structure wherein said electric motor is rigidly mounted to said suspension component.

17. An assembly as set forth in claim 13 wherein said motor output of said electric motor comprises first and second motor output shafts each being coaxial with said lateral axis of rotation for rotating at a first rotational speed and wherein said first and second wheels rotate at a second rotational speed less than said first rotational speed.

18. An assembly as set forth in claim 17 including a first eccentric cam mounted for rotation with said first motor output shaft and a second eccentric cam mounted for rotation with said second motor output shaft, said first eccentric cam defining said first gear drive axis and said second eccentric cam defining said second gear drive axis wherein said first and second gear drives each comprise a cycloid gear reduction with said first and third gear components each comprising a first cycloid member having a central bore for receiving and rotatably supporting said first or second eccentric cam and a plurality of circumferential bores spaced radially about a circumference of said first cycloid member relative to said central bore and wherein said second and fourth gear components each comprise a second cycloid member fixed to said respective first or second wheels and including a plurality of drive members spaced about a circumference of said second cycloid member with each drive member being received in a corresponding one of said circumferential bores such that said eccentric cam drives said second cycloid member via said first cycloid member achieve speed reduction at said first and second wheels.

19. An assembly as set forth in claim 18 wherein said motor output shaft is non-concentric with said central bore and wherein each of said drive members is non-concentric with said respective circumferential bore.

20. An assembly as set forth in claim 17 wherein said first and second gear drives each comprise an epicycloid gear reduction with said first and third gear components each comprising a non-rotating ring gear and said second and fourth gear components each comprising a drive gear defining said second gear drive axis and in driving engagement with said ring gear, said drive gear operably coupled to said motor output via a chain and sprocket assembly to receive driving input and operably coupled to said respective first or second wheel to provide driving output.