Tank steer system for vehicle

Patent metadata

Field	Value
Publication number	US-12448041-B2
Application number	US-202318498503-A
Country	US
Kind code	B2
Filing date	Oct 31, 2023
Priority date	Oct 31, 2023
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

A drivetrain assembly for a vehicle having a propulsion system configured to drive first and second half shafts is provided. In one example, the drivetrain assembly includes a gearbox assembly configured to couple to the propulsion system, a planetary gear set selectively coupled to an output of the gearbox assembly, and a differential having a differential case, the differential configured to operably couple to the first and second half shafts. The drivetrain assembly operates in a tank steer mode by selectively grounding the differential case and connecting the output of the gearbox assembly to the first half shaft via the planetary gear set, such that the propulsion system rotates the first half shaft in the first direction and, via the differential, rotates the second half shaft in the opposite second direction.

First claim

What is claimed is:

1. A drivetrain assembly for a vehicle having a propulsion system configured to drive first and second half shafts, the drivetrain assembly comprising:
a gearbox assembly configured to couple to the propulsion system;
a planetary gear set selectively coupled to an output of the gearbox assembly; and
a differential having a differential case, the differential configured to operably couple to the first and second half shafts;
wherein the drivetrain assembly is selectively operable in a tank steer mode that rotates one or more wheels on a first side of the vehicle in a first direction, and rotates one or more wheels on an opposite second side of the vehicle in a second direction opposite the first direction to thereby rotate the vehicle, and
wherein the drivetrain assembly operates in the tank steer mode by selectively grounding the differential case and connecting the output of the gearbox assembly to the first half shaft via the planetary gear set, such that the propulsion system rotates the first half shaft in the first direction and, via the differential, rotates the second half shaft in the opposite second direction.

2. The drivetrain assembly of claim 1 , further comprising a pawl configured to ground the differential case in the tank steer mode.

3. The drivetrain assembly of claim 2 , wherein the pawl is hinged to a ground and is spring-loaded to engage the differential case.

4. The drivetrain assembly of claim 3 , wherein the ground is an axle case.

5. The drivetrain assembly of claim 3 , further comprising:
a first selectable connector configured to selectively rotationally couple the gearbox assembly output to a sun gear of the planetary gear set or a planetary carrier of the planetary gear set; and
a second selectable connector configured to selectively rotationally couple the planetary carrier to the first half shaft or the differential case.

6. The drivetrain assembly of claim 5 , wherein the second selectable connector disengages the pawl from the differential case when the second selectable connector rotationally couples the planetary carrier and the differential case.

7. The drivetrain assembly of claim 5 , wherein the first and second selectable connectors are dog clutches.

8. The drivetrain assembly of claim 1 , wherein a ring gear of the planetary gear set is grounded.

9. The drivetrain assembly of claim 1 , further comprising:
a first selectable connector configured to selectively rotationally couple the gearbox assembly output to a sun gear of the planetary gear set or a planetary carrier of the planetary gear set; and
a second selectable connector configured to selectively rotationally couple the planetary carrier to the first half shaft or the differential case.

10. The drivetrain assembly of claim 9 , wherein in the tank steer mode, the first selectable connector is coupled between the gearbox assembly output and the sun gear, and the second selectable connector is coupled between the planetary carrier and the first half shaft,
wherein in a high gear drive mode, the first selectable connector is coupled between the gearbox assembly output and the planetary carrier, and the second selectable connector is coupled between the planetary carrier and the differential case such that the first and second half shafts rotate in the same direction, and
wherein in a low gear drive mode, the first selectable connector is coupled between the gearbox assembly output and the sun gear, and the second selectable connector is coupled between the planetary carrier and the differential case such that the first and second half shafts rotate in the same direction.

11. A vehicle configured to perform a tank steer operation, the vehicle comprising:
a propulsion system;
a differential having a differential case;
first and second half shafts operably coupled to the differential;
a gearbox assembly coupled to the propulsion system; and
a planetary gear set coupled to an output of the gearbox assembly;
wherein the vehicle is selectively operable in a tank steer mode that rotates one or more wheels on a first side of the vehicle in a first direction, and rotates one or more wheels on an opposite second side of the vehicle in a second direction opposite the first direction to thereby rotate the vehicle, and
wherein the vehicle operates in the tank steer mode by selectively grounding the differential case and connecting the output of the gearbox assembly to the first half shaft via the planetary gear set, such that the propulsion system rotates the first half shaft in the first direction and, via the differential, rotates the second half shaft in the opposite second direction.

12. The vehicle of claim 11 , further comprising a pawl configured to ground the differential case in the tank steer mode.

13. The vehicle of claim 12 , wherein the pawl is hinged to a ground and is spring-loaded to engage the differential case.

14. The vehicle of claim 13 , wherein the ground is an axle case.

15. The vehicle of claim 13 , further comprising:
a first selectable connector configured to selectively rotationally couple the gearbox assembly output to a sun gear of the planetary gear set or a planetary carrier of the planetary gear set; and
a second selectable connector configured to selectively rotationally couple the planetary carrier to the first half shaft or the differential case.

16. The vehicle of claim 15 , wherein the second selectable connector disengages the pawl from the differential case when the second selectable connector rotationally couples the planetary carrier and the differential case.

17. The vehicle of claim 15 , wherein the first and second selectable connectors are dog clutches.

18. The vehicle of claim 15 , wherein in the tank steer mode, the first selectable connector is coupled between the gearbox assembly output and the sun gear, and the second selectable connector is coupled between the planetary carrier and the first half shaft,
wherein in a high gear drive mode, the first selectable connector is coupled between the gearbox assembly output and the planetary carrier, and the second selectable connector is coupled between the planetary carrier and the differential case such that the first and second half shafts rotate in the same direction, and
wherein in a low gear drive mode, the first selectable connector is coupled between the gearbox assembly output and the sun gear, and the second selectable connector is coupled between the planetary carrier and the differential case such that the first and second half shafts rotate in the same direction.

19. The vehicle of claim 11 , wherein a ring gear of the planetary gear set is grounded.

Assignees

• Fca Us Llc

Inventors

• Vermeulen Chad J
• Attibele Pradeep R
• Levine Mark A

Classifications

• F16H37/082

  and additional planetary reduction gears · CPC title

• F16H48/08

  comprising bevel gears · CPC title

• F16H48/24

  using positive clutches or brakes · CPC title

• B60K17/165

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

• B62D11/12 Primary

  using separate change-speed gearings · CPC title