Drive axle for an electrically driven work machine

Patent metadata

Field	Value
Publication number	US-11518191-B2
Application number	US-201816763212-A
Country	US
Kind code	B2
Filing date	Oct 8, 2018
Priority date	Nov 10, 2017
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

A drive axle for a work machine for driving wheels that are coupled to the drive axle. The drive axle includes a spur gear stage with an input shaft. A differential gear unit couples to the spur gear stage and to the wheels via wheel drive shafts. The drive axle further includes a reduction gear unit with an output element couples to the input shaft of the spur gear stage—and an input element which couples to an output shaft of an electric drive machine.

First claim

The invention claimed is:

1. A drive axle for a work machine for driving wheels which are coupled to the drive axle, the drive axle comprising:
an electric drive machine coupled to a reduction gear unit, the reduction gear unit being configured to receive torque from the electric drive machine;
a spur gear stage coupled to the reduction gear unit and configured to receive torque from the reduction gear unit; and
a differential gear unit coupled to the spur gear stage and configured to transmit torque received from the spur gear stage to the wheels coupled to the drive axle,
wherein the electric drive machine includes a first stator section and a second stator section that are electrically isolated from one another, the first stator section being configured to induce a first alternating field of a circumferential section of 180 degrees of a circumference of the electric drive machine, and the second stator section being configured to induce a second alternating field of a circumferential section of a remaining 180 degree circumference of the electric drive machine.

2. The drive axle of claim 1 , wherein the reduction gear unit is embodied as a planetary gear unit that includes at least one sun gear, at least one planetary carrier, which carries at least one planetary gear, and a ring gear, and wherein the least one sun gear engages with the at least one planetary gear, the at least one planetary gear also engages with the ring gear, the at least one planetary carrier being coupled to the spur gear stage, and the at least one sun gear being coupled to the electric drive machine.

3. The drive axle of claim 1 , further comprising an axle casing in which the spur gear stage, the differential gear unit and the reduction gear unit are accommodated, wherein the electric drive machine is mounted on the axle casing.

4. The drive axle of claim 1 , wherein the electric drive machine is arranged on a section of the work machine to which the drive axle is attached, and wherein the electric drive machine is coupled to the reduction gear unit via a coupling element.

5. The drive axle of claim 1 , wherein a transfer case is provided between the reduction gear unit and the spur gear stage.

6. The drive axle of claim 1 , wherein a transmission ratio between the reduction gear unit and the wheels is 1/100 or less.

7. The drive axle of claim 1 , wherein the electric drive machine includes a rotor which is provided radially within the first and second stator sections, wherein the first stator section is assigned a first power electronics unit, and the second stator section is assigned a second power electronics unit.

8. The drive axle of claim 7 , wherein the first and second power electronics units are actuated by a synchronization device and respective output power levels of the first and second power electronics units can be regulated independently of one another.

9. The drive axle of claim 1 , wherein the electric drive machine is embodied as an asynchronous machine.

10. The drive axle of claim 1 , wherein the electric drive machine is configured to operate at a rotational speed of 15,000 rpm or greater.

11. The drive axle of claim 10 , wherein the electric work machine is configured with a rated voltage of 48 to 60 volts.

12. A powertrain comprising:
a first drive axle coupled to a first set of wheels, and
a second drive axle coupled to a second set of wheels,
wherein the first drive axle is provided with a transfer case which is coupled by an intermediate shaft to the second drive axle, in order to transmit a drive force, which is output by an electric drive machine, to the second drive axle,
wherein the first drive axle includes a reduction gear unit coupled to the electric drive machine and configured to receive torque from the electric drive machine, a first drive axle spur gear stage coupled to the reduction gear unit and configured to receive torque from the reduction gear unit, and a first drive axle differential gear unit coupled to the first drive axle spur gear stage, and
wherein the electric drive machine includes a first stator section and a second stator section that are electrically isolated from one another, the first stator section being configured to induce a first alternating field of a circumferential section of 180 degrees of a circumference of the electric drive machine, and the second stator section being configured to induce a second alternating field of a circumferential section of a remaining 180 degree circumference of the electric drive machine.

13. The powertrain of claim 12 , wherein the second drive axle incudes a second drive axle spur gear stage, and a second drive axle differential gear unit which is coupled to the second drive axle spur gear stage, wherein the intermediate shaft is coupled to the transfer case via the second drive axle spur gear stage.

14. A work machine comprising:
an energy storage unit,
power electronics units for supplying power to an electric drive machine, and
a drive axle that includes a reduction gear unit coupled to the electric drive machine and configured to receive torque from the electric drive machine, a spur gear stage configured to receive torque from the reduction gear unit, and a differential gear unit coupled to the spur gear stage and configured to receive torque from the spur gear stage, and
wherein the electric drive machine includes a first stator section and a second stator section that are electrically isolated from one another, the first stator section being configured to induce a first alternating field of a circumferential section of 180 degrees of a circumference of the electric drive machine, and the second stator section being configured to induce a second alternating field of a circumferential section of a remaining 180 degree circumference of the electric drive machine.

Assignees

• Zahnradfabrik Friedrichshafen

Inventors

• Bebeti Migen
• Stempfer Gerhard
• Döring Jan
• Tepfenhart Peter
• Feuchtner Norbert

Classifications

• B60B35/14

  composite or split, e.g. half- axles; Couplings between axle parts or sections · CPC title

• B60K2001/001

  one motor mounted on a propulsion axle for rotating right and left wheels of this axle · CPC title

• B60B35/125 Primary

  of the planetary type · CPC title

• H02K7/006

  Structural association of a motor or generator with the drive train of a motor vehicle · CPC title

• H02K7/116

  with gears · CPC title