AXLE DRIVE UNIT FOR A HYBRID ELECTRIC VEHICLE

• US 20090197727A1
• Filed: 02/05/2008
• Published: 08/06/2009
• Est. Priority Date: 02/05/2008
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Janson, David A.
• Granted Patent: US 7,762,366 B2
• Time in Patent Office: Days
• US Class Current: 475/5
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: F16H 2048/364 using electric or hydraulic motors
• CPC Class Codes: F16H 48/08 comprising bevel gears
• CPC Class Codes: F16H 48/36 characterised by intentionally generating speed difference between outputs
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor

Abstract

A drive unit for a hybrid electric motor vehicle includes an engine, an electric machine including a rotor, a layshaft gearset including an input driveably connected to the engine and an output, for transmitting power between the input and the output and producing a first speed differential that causes a speed of the input to exceed a speed of the output, first and second driveshafts, a differential mechanism driveably connected to said output, for transmitting power between said output and the driveshafts, and a planetary gear unit driveably connected to the output and the rotor, for transmitting power between said rotor and said output and producing a second speed differential that causes a speed of the rotor to exceed the speed of the output.

Claims

1. A drive unit for a hybrid electric motor vehicle that includes an engine, comprising:

an electric machine including a rotor;

a layshaft gearset including an input driveably connected to the engine and an output, for transmitting power between the input and the output and producing a first speed differential that causes a speed of the input to exceed a speed of the output;

a first driveshaft and a second driveshaft;

a differential mechanism driveably connected to the output, for transmitting power between the output and the driveshafts;

a planetary gear unit driveably connected to the output and the rotor, for transmitting power between the rotor and the output and producing a second speed differential that causes a speed of the rotor to exceed the speed of the output.

2. The drive unit of claim 1 wherein:

the input comprises a bevel pinion driveably connectable to the engine; and

the output comprises a bevel gear meshing with the bevel pinion and secured to a layshaft.

3. The drive unit of claim 1 wherein:

the input comprises a pinion secured to a layshaft; and

the output comprises a gear meshing with the pinion and driveably connected to the differential mechanism.

4. The drive unit of claim 1 wherein:

the input comprises a bevel pinion driveably connectable to the engine; and

the output comprises a gear driveably connected to the differential mechanism; and

the layshaft gear set further comprises a bevel gear meshing with the bevel pinion and secured to a layshaft, and a pinion secured to the layshaft and meshing with the gear.

5. The drive unit of claim 1 wherein the planetary gear unit further comprises:

a first sun gear driveably connected to the rotor, a first ring gear held against rotation, a first carrier driveably connected to the input, and first planet pinions supported for rotation on the first carrier and meshing with the first sun gear and the first ring gear.

6. The drive unit of claim 1 wherein the planetary gear unit further comprises:

a first the planetary gear set that includes a first sun gear driveably connected to the rotor, a first ring gear held against rotation, a first carrier, and first planet pinions supported for rotation on the first carrier and meshing with the first sun gear and the first ring gear; and

a second the planetary gear set that includes a second sun gear driveably connected to the first carrier, a second ring gear held against rotation, a second carrier driveably connected to the differential mechanism, and second planet pinions supported for rotation on the second carrier and meshing with the second sun gear and the second ring gear.

7. The drive unit of claim 1 wherein:

the electric machine further comprises a stator surrounding the rotor;

the planetary gear unit includes a non-rotating member; and

the drive unit further comprises a casing fixed against rotation, the stator and nonrotating member being secured to the casing.

8. The drive unit of claim 1 wherein the differential mechanism further comprises:

a third sun gear driveably connected to the first drive shaft;

a third ring gear driveably connected to the output;

a third carrier driveably connected to the second driveshaft;

third planet pinions supported for rotation on the third carrier and meshing with the third sun gear; and

fourth planet pinions supported for rotation on the third carrier and meshing with the third ring gear and the third planet pinions.

9. The drive unit of claim 1 wherein the differential mechanism and the planetary gear unit are substantially aligned with an axis, and the differential mechanism is spaced along the axis from the planetary gear set;

and

the drive unit further comprises;

a casing fixed against rotation;

a first bearing located at a side of the differential mechanism that is axially opposite the planetary gear unit, the first bearing supporting the output on the casing for rotation about the axis; and

a second bearing located at a side of the differential gear unit that is axially opposite the differential mechanism, and supporting the output on the casing for rotation about the axis.

10. The drive unit of claim 1 further comprising a unit for alternately opening and closing a drive connection between the engine and the input.

11. The drive unit of claim 1 wherein the electric machine is an electric motor/generator.

12. A drive unit for a hybrid electric motor vehicle that includes an engine, comprising:

an electric machine including a rotor;

a casing fixed against rotation;

a drum supported for rotation on the casing;

a layshaft gearset for transmitting power between the engine and the drum and producing a first speed reduction between a speed of the engine and a speed of the drum;

a first driveshaft and a second driveshaft;

a differential mechanism driveably connected to the drum and the rotor, for transmitting power among the drum, the rotor and the driveshafts;

a planetary gear unit driveably connected to the drum and the rotor and including a member secured to the casing, for transmitting power between the rotor and the differential mechanism and producing a second speed reduction between a speed of the rotor and the speed of the drum.

13. The drive unit of claim 12 wherein the layshaft gearset comprises:

a layshaft;

a bevel pinion driveably connectable to the engine; and

a bevel gear meshing with the bevel pinion and secured to the layshaft.

14. The drive unit of claim 12 wherein the layshaft gearset comprises:

a layshaft;

a bevel pinion driveably connectable to the engine;

a bevel gear meshing with the bevel pinion and secured to the layshaft;

a gear driveably connected to the differential mechanism; and

a pinion secured to the layshaft and meshing with the gear.

15. The drive unit of claim 12 wherein the planetary gear unit further comprises:

a first sun gear driveably connected to the rotor, a first ring gear secured to the casing, a first carrier driveably connected to the input, and first planet pinions supported for rotation on the first carrier and meshing with the first sun gear and the first ring gear.

16. The drive unit of claim 12 wherein the planetary gear unit further comprises:

a first the planetary gear set that includes a first sun gear driveably connected to the rotor, a first ring gear secured to the casing, a first carrier, and first planet pinions supported for rotation on the first carrier and meshing with the first sun gear and the first ring gear; and

a second the planetary gear set that includes a second sun gear driveably connected to the first carrier, a second ring gear secured to the casing, a second carrier driveably connected to the differential mechanism, and second planet pinions supported for rotation on the second carrier and meshing with the second sun gear and the second ring gear.

17. The drive unit of claim 12 wherein the differential mechanism further comprises:

a third sun gear driveably connected to the first drive shaft;

a third ring gear driveably connected to the drum;

a third carrier driveably connected to the second driveshaft;

third planet pinions supported for rotation on the third carrier and meshing with the third sun gear; and

fourth planet pinions supported for rotation on the third carrier and meshing with the third ring gear and the third planet pinions.

18. The drive unit of claim 12 wherein the differential mechanism and the planetary gear unit are substantially aligned with an axis, and the differential mechanism is spaced along the axis from the planetary gear set;

and

a first bearing located at a side of the differential mechanism that is axially opposite the planetary gear unit, the first bearing supporting the drum on the casing for rotation about the axis; and

a second bearing located at a side of the differential gear unit that is axially opposite the differential mechanism, and supporting the drum on the casing for rotation about the axis.

19. The drive unit of claim 12 further comprising a unit for alternately opening and closing a drive connection between the engine and the input.

20. The drive unit of claim 12 wherein the electric machine is an electric motor/generator.