Electric axle with compact electric machine and gearbox arrangement

Patent metadata

Field	Value
Publication number	US-12365230-B2
Application number	US-202318173660-A
Country	US
Kind code	B2
Filing date	Feb 23, 2023
Priority date	Mar 15, 2022
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

An electric axle is provided. The electric axle includes, in one example, a first electric machine directly coupled to a first planetary gear set, a second electric machine directly coupled to a second planetary gear set and a housing. The housing includes a first section that encloses the first electric machine and the first planetary gear set, a second section that encloses the second electric machine and the second planetary gear set, and a decreased diameter section that extends between the first section and the second section.

First claim

The invention claimed is:

1. An electric axle, comprising:
a first electric machine directly coupled to a first planetary gear set;
a second electric machine directly coupled to a second planetary gear set;
a support structure comprising a first vertically extending protrusion and a second vertically extending protrusion;
wheels positioned at extreme ends of the electric axle and outboard of the support structure; and
a housing including:
a first section that encloses the first electric machine and the first planetary gear set, wherein the first section is vertically below the first vertically extending protrusion of the support structure;
a second section that encloses the second electric machine and the second planetary gear set, wherein the second section is vertically below the second vertically extending protrusion of the support structure; and
a decreased diameter section that extends between the first section, the second section, the first vertically extending protrusion, and the second vertically extending protrusion.

2. The electric axle of claim 1 , wherein the electric axle is a beam axle, and wherein the support structure comprises an engine recess profiled to mate with a portion of an engine.

3. The electric axle of claim 1 , wherein in each of the first and second planetary gear sets a sun gear is directly coupled to the respective electric machine and a carrier is directly coupled to a drive wheel.

4. The electric axle of claim 1 , wherein the first and second planetary gear sets each includes planet gears axially offset from a sun gear.

5. The electric axle of claim 4 , wherein the first and second planetary gear sets each includes a ring gear that meshes with the planet gears and is mechanically grounded by the housing.

6. The electric axle of claim 1 , wherein the first and second planetary gear sets are each simple planetary gear sets.

7. The electric axle of claim 1 , wherein the first and second planetary gear sets do not have any clutches coupled thereto.

8. The electric axle of claim 1 , wherein the first and second electric machines are axial flux motors, and wherein the support structure is a cradle shaped to wrap around and mate with powertrain components.

9. The electric axle of claim 1 , wherein the housing is symmetric about an axis that vertically extends through the decreased diameter section, and wherein the support structure comprises lateral asymmetry.

10. An electric drive assembly, comprising:
an electric beam axle comprising:
a first electric machine directly coupled to a first planetary gear set;
a second electric machine directly coupled to a second planetary gear set;
a housing including:
a first section that encloses the first electric machine and the first planetary gear set;
a second section that encloses the second electric machine and the second planetary gear set; and
a decreased diameter section extending between the first section and the second section; and

a support structure including an axle recess that at least partially encloses the electric beam axle, wherein the support structure includes a first vertically extending protrusion and a second vertically extending protrusion, wherein the decreased diameter section of the housing is positioned laterally between the first and second vertically extending protrusions, and wherein the support structure includes an engine recess positioned longitudinally behind the axle recess and profiled to mate with a portion of an engine.

11. The electric drive assembly of claim 10 , wherein the first vertically extending protrusion and the second vertically extending protrusion have varying heights.

12. The electric drive assembly of claim 10 , wherein the electric drive assembly is an unsprung mass.

13. An electric beam axle, comprising:
a first axial flux motor-generator directly coupled to a first planetary gear set that is directly coupled to a drive wheel; and
a second axial flux motor-generator directly coupled to a second planetary gear set that is directly coupled to another drive wheel;
wherein the first and second axial flux motor-generators independently rotate; and
a housing that is profiled to mate with a first recess in a hybrid drive support structure, wherein the hybrid drive support structure includes a second recess sized to mate with an internal combustion engine.

14. The electric beam axle of claim 13 , wherein the first planetary gear set and the second planetary gear set each includes a first set of planet gears and a second set of planet gears that is axially offset from the first set of planet gears.

15. The electric beam axle of claim 14 , wherein the second set of planet gears is position axially between the first set of planet gears and the corresponding axial flux motor-generator.

16. The electric beam axle of claim 13 , wherein the first planetary gear set and the second planetary gear set each includes a sun gear coupled to their respective radial-flux motor-generator and a carrier coupled to a respective drive wheel.

17. The electric beam axle of claim 13 , wherein the housing is symmetric about a vertical axis that extends through a reduced diameter section that is positioned laterally between a first section and a second section that at least partially enclose the first axial flux motor-generator and the second axial flux motor-generator, respectively.

Assignees

• Dana Automotive Systems Group

Inventors

• Perakes Andy
• Engerman Eric M
• Nelms Ryan D
• Sigmon Rick C

Classifications

• F16H2057/02052

  Axle units; Transfer casings for four wheel drive · CPC title

• F16H2057/02034

  Gearboxes combined or connected with electric machines · CPC title

• F16H57/02

  Gearboxes; Mounting gearing therein · CPC title

• B60Y2200/92

  Hybrid vehicles · CPC title

• B60K17/04

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