Axle assembly for an electric vehicle, vehicle, and method for operating an axle assembly

Patent metadata

Field	Value
Publication number	US-12240308-B2
Application number	US-202318526185-A
Country	US
Kind code	B2
Filing date	Dec 1, 2023
Priority date	Dec 1, 2022
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

The disclosure relates to an axle assembly for an electric vehicle. The axle assembly comprises a first electric machine, a second electric machine, and a spur gear unit comprising at least one spur gear stage and a differential gear unit. The at least one spur gear stage is drivingly coupled to the differential gear unit. Moreover, an output shaft of the first electric machine, an output shaft of the second electric machine, and an input shaft of the spur gear stage are formed by a common shaft. Additionally, the differential gear unit comprises a first output flange for drivingly coupling a first wheel to the axle assembly and a second output flange for drivingly coupling a second wheel to the axle assembly. Furthermore, a vehicle comprising such an axle assembly is presented. The differential gear unit is arranged centrally with respect to a vehicle width direction.

First claim

What is claimed is:

1. An axle assembly for an electric vehicle, comprising:
a first electric machine configured to minimize electromagnetic losses of the first electric machine in a first operational range;
a second electric machine configured to minimize electromagnetic losses of the second electric machine in a second operational range, wherein the second operational range is different from the first operational range;
a shaft comprising a singular pinion rotationally fixed to the shaft between a first end of the shaft and a second end of the shaft opposite the first end, wherein the first electric machine is coupled to the first end of the shaft, and the second electric machine is coupled to the second end of the shaft, and wherein the shaft is supported on exactly two bearing units; and
a spur gear unit comprising at least one spur gear stage and a differential gear unit, the at least one spur gear stage being drivingly coupled to the differential gear unit,
wherein the singular pinion engages with a gear of the spur gear unit, and
wherein the differential gear unit comprises a first output flange for drivingly coupling a first wheel to the axle assembly and a second output flange for drivingly coupling a second wheel to the axle assembly.

2. The axle assembly of claim 1 , wherein the differential gear unit is supported on exactly two bearing units.

3. The axle assembly of claim 1 , wherein the at least one spur gear stage comprises an intermediate shaft being arranged parallel to the shaft.

4. The axle assembly of claim 3 , wherein the intermediate shaft is supported on exactly two bearing units.

5. The axle assembly of claim 1 , wherein the differential gear unit is rotatable around an axis of rotation being arranged parallel to the shaft.

6. The axle assembly of claim 1 , wherein the first electric machine and the second electric machine are of a same type of machine.

7. The axle assembly of claim 1 , wherein the first electric machine and the second electric machine are different types of machines.

8. The axle assembly of claim 7 , wherein one out of the first electric machine or the second electric machine is an induction machine, a synchronous reluctance machine, a permanent magnet-assisted synchronous reluctance machine, a switched reluctance machine, or an electrically excited rotor synchronous machine, and
wherein a respective other one of the first electric machine or the second electric machine is a permanent magnet synchronous machine, an induction machine, a synchronous reluctance machine, a permanent magnet-assisted synchronous reluctance machine, a switched reluctance machine, an electrically excited rotor synchronous machine, a transverse flux machine, or a variable flux machine.

9. The axle assembly of claim 1 , wherein at least one of the first electric machine or the second electric machine comprises an external rotor.

10. The axle assembly of claim 1 , further comprising:
an inverter unit, wherein the inverter unit is at least partially arranged between the first electric machine and the second electric machine.

11. The axle assembly of claim 1 , further comprising:
a first axle shaft being drivingly connected to the first output flange; and
a second axle shaft being drivingly connected to the second output flange,
wherein the first axle shaft and the second axle shaft have a same length.

12. A vehicle, comprising:
an axle assembly, comprising:
a first electric machine configured to minimize electromagnetic losses of the first electric machine in a first operational range;
a second electric machine configured to minimize electromagnetic losses of the second electric machine in a second operational range, wherein the second operational range is different from the first operational range;
a shaft comprising a singular pinion rotationally fixed to the shaft between a first end of the shaft and a second end of the shaft opposite the first end, wherein the first electric machine is coupled to the first end of the shaft, and the second electric machine is coupled to the second end of the shaft, and wherein the shaft is supported on exactly two bearing units; and
a spur gear unit comprising at least one spur gear stage and a differential gear unit, the at least one spur gear stage being drivingly coupled to the differential gear unit,
wherein the singular pinion engages with a gear of the spur gear unit, and
wherein the differential gear unit comprises a first output flange for drivingly coupling a first wheel to the axle assembly and a second output flange for drivingly coupling a second wheel to the axle assembly,
wherein the differential gear unit is arranged centrally with respect to a vehicle width direction.

13. The vehicle of claim 12 , wherein the differential gear unit is supported on exactly two bearing units.

14. The vehicle of claim 12 , wherein the at least one spur gear stage comprises an intermediate shaft being arranged parallel to the shaft.

15. The vehicle of claim 14 , wherein the intermediate shaft is supported on exactly two bearing units.

16. A method for operating an axle assembly, comprising:
operating only one out of a first electric machine of the axle assembly and a second electric machine of the axle assembly in a first driving mode, wherein the first electric machine is coupled to a first end of a shaft comprising a singular pinion rotationally fixed to the shaft between the first end of the shaft and a second end of the shaft opposite the first end, wherein the second electric machine is coupled to the second end of the shaft, wherein the first electric machine is configured to minimize electromagnetic losses of the first electric machine in a first operational range, wherein the second electric machine is configured to minimize electromagnetic losses of the second electric machine in a second operational range, wherein the second operational range is different from the first operational range, and wherein the shaft is supported on exactly two bearing units; and
operating both the first electric machine and the second electric machine in a second driving mode,
wherein the axle assembly further comprises a spur gear unit comprising at least one spur gear stage and a differential gear unit, the at least one spur gear stage being drivingly coupled to the differential gear unit,
wherein the singular pinion engages with a gear of the spur gear unit, and
wherein the differential gear unit comprises a first output flange for drivingly coupling a first wheel to the axle assembly and a second output flange for drivingly coupling a second wheel to the axle assembly.

17. The method of claim 16 , wherein the first electric machine and the second electric machine are different types of machines.

18. The method of claim 17 , wherein one out of the first electric machine or the second electric machine is an induction machine, a synchronous reluctance machine, a permanent magnet-assisted synchronous reluctance machine, a switched reluctance machine, or an electrically excited rotor synchronous machine, and
wherein a respective other one of the first electric machine or the second electric machine is a permanent magnet synchronous machine, an induction machine, a synchronous reluctance machine, a permanent magnet-assisted synchronous reluctance machine, a switched reluctance machine, an electrically excited rotor synchronous machine, a transverse flux machine, or a variable flux machine.

19. The method of claim 16 , wherein the differential gear unit is supported on exactly two

Assignees

• Volvo Car Corp

Inventors

• Petrov Peter
• Lennström Håkan

Classifications

• B60K17/16

  of differential gearing · CPC title

• B60K17/165

  provided between independent half axles (B60K17/18, B60K17/20 take precedence) · CPC title

• B60K17/02

  characterised by arrangement, location, or kind of clutch · CPC title

• B60K1/02 Primary

  comprising more than one electric motor · CPC title