Systems and methods for providing adjustable lubrication to a tandem axle

Patent metadata

Field	Value
Publication number	US-11598409-B2
Application number	US-202016914070-A
Country	US
Kind code	B2
Filing date	Jun 26, 2020
Priority date	Jun 26, 2020
Publication date	Mar 7, 2023
Grant date	Mar 7, 2023

Abstract

Methods and systems are provided for adjusting a lubrication system based on an axle configuration of a tandem axle with a disconnect feature. In one example, a method may include adjusting an oil level in an axle sump of a tandem axle based on an axle configuration of the tandem axle (e.g., whether the tandem axle is operating with one of a 6×4 axle configuration and a 6×2 axle configuration), the axle sump selectably coupled to an external reservoir via a first passage and a second passage, the first passage including an electric pump, the second passage including a valve, and the tandem axle coupled to a drivetrain of a motor vehicle. In this way, an amount of oil in the axle sump may be adjusted based on the tandem axle configuration.

First claim

The invention claimed is:

1. A method, comprising:
adjusting an oil level in an axle sump of a tandem axle based on an axle configuration of the tandem axle, the axle sump selectably coupled to an external reservoir via a first oil passage and a second oil passage, the first oil passage including an electric pump, the second oil passage including a valve, and the tandem axle coupled to a drivetrain of a motor vehicle, wherein the oil level in the axle sump is determined based on a signal from a level sensor, the level sensor coupled to the axle sump.

2. The method of claim 1 , wherein the second oil passage is a gravity feed.

3. A method, comprising:
adjusting an oil level in an axle sump of a tandem axle based on an axle configuration of the tandem axle, the axle sump selectably coupled to an external reservoir via a first oil passage and a second oil passage, the first oil passage including an electric pump, the second oil passage including a valve, and the tandem axle coupled to a drivetrain of a motor vehicle, wherein while the tandem axle operates with a first axle configuration, a drive shaft of an engine provides torque to a first axle and a second axle, each of the first axle and the second axle coupled to at least two wheels; and
while the tandem axle operates with a second axle configuration, the drive shaft of the engine provides torque to the first axle and does not provide torque to the second axle.

4. The method of claim 3 , wherein adjusting the oil level in the axle sump of the tandem axle based on an axle configuration of the tandem axle includes:
responsive to the tandem axle transitioning from operating with the first axle configuration to operating with the second axle configuration, flowing oil from the axle sump to the external reservoir through the first oil passage by activating the electric pump, and blocking flow through the second oil passage by closing the valve; and
responsive to the oil level in the axle sump at or below a first threshold oil level while the tandem axle operates with the second axle configuration, blocking flow through the first oil passage by deactivating the electric pump.

5. The method of claim 4 , wherein adjusting the oil level in the axle sump of the tandem axle further includes:
responsive to the tandem axle transitioning from operating with the second axle configuration to operating with the first axle configuration, flowing oil from the external reservoir to the axle sump through the second oil passage by opening the valve; and
responsive to the oil level in the axle sump at or above a second threshold oil level while the tandem axle operates with the first axle configuration, blocking flow through the second oil passage by closing the valve.

6. The method of claim 5 , wherein the first threshold oil level is lower than the second threshold oil level.

7. The method of claim 5 , wherein the tandem axle transitions from the first axle configuration to the second axle configuration responsive to at least one of a vehicle speed above a threshold vehicle speed, a user input, and a road condition, and the tandem axle transitions from the second axle configuration to the first axle configuration responsive to at least one of a vehicle speed below the threshold vehicle speed, the user input, and the road condition.

8. The method of claim 3 , wherein the oil level in the axle sump is determined based on a signal from a level sensor, the level sensor coupled to the axle sump.

9. A method, comprising:
responsive a tandem axle transitioning from a 6×4 axle configuration to a 6×2 axle configuration, adjusting an oil level in an axle sump of the tandem axle to a first threshold level, the axle sump of the tandem axle selectably coupled to an external reservoir; and
responsive to the tandem axle transitioning from the 6×2 axle configuration to the 6×4 axle configuration, adjusting the oil level in the axle sump of the tandem axle to a second threshold level, the second threshold level higher than the first threshold level.

10. The method of claim 9 , wherein the tandem axle is coupled to a drive shaft of a motor vehicle, the drive shaft providing torque to a first axle while operating with the 6×2 axle configuration, and the drive shaft providing torque to each of the first axle and a second axle while operating with the 6×4 axle configuration.

11. The method of claim 10 , wherein the axle sump is selectably coupled to the external reservoir via a first oil passage and a second oil passage, the first oil passage including an electric pump, and the second oil passage including a valve, the valve actuatable between an open position and a closed position.

12. The method of claim 11 , wherein, when activated, the electric pump flows oil from the axle sump to the external reservoir through the first oil passage and, when not activated, the electric pump does not flow oil from the axle sump to the external reservoir through the first oil passage.

13. The method of claim 12 , wherein adjusting the oil level in the axle sump of the tandem axle to the first threshold level includes:
responsive to the oil level in the axle sump above the first threshold level, flowing oil from the axle sump to the external reservoir through the first oil passage by activating the electric pump;
blocking oil from flowing from the external reservoir to the axle sump through the second oil passage by closing the valve; and
responsive to the oil level in the axle sump at or below the first threshold level, deactivating the electric pump.

14. The method of claim 13 , wherein adjusting the oil level in the axle sump of the tandem axle to the second threshold level includes:
responsive to the oil level in the axle sump below the second threshold level, flowing oil from the external reservoir to the axle sump through the second oil passage by opening the valve; and
responsive to the oil level in the axle sump at or above the second threshold level, closing the valve.

15. The method of claim 9 , wherein the oil level is determined based on a signal from a level sensor coupled to the axle sump.

16. A system, comprising:
a tandem axle, the tandem axle coupled to a powertrain of a motor vehicle;
an axle sump fluidically coupled to the tandem axle;
an external reservoir;
a first oil passage selectably coupling the external reservoir to the axle sump via an electric pump;
a second oil passage selectably coupling the external reservoir to the axle sump via a valve; and
a controller including instructions stored in non-transitory memory that, when executed, cause the controller to:
adjust an oil level in the axle sump based on an axle configuration of the tandem axle, the oil level adjusted differently while operating with a first axle configuration relative to operating with a second axle configuration.

17. The system of claim 16 , wherein the tandem axle transitions from the first axle configuration to the second axle configuration in response to a vehicle speed exceeding a threshold vehicle speed, and the tandem axle transitions from the second axle configuration to the first axle configuration in response to the vehicle speed below the threshold vehicle speed.

18. The system of claim 17 , wherein the first axle configuration includes providing torque to each of a first axle and a second axle, and the second axle configuration includes providing torque to a first axle while not providing torque to the second axle.

19. The system of claim 18 , wherein, to adjust the oil level in the axle sump based on the axle config

Assignees

• Dana Heavy Vehicle Sys Group

Inventors

• Balistreri Lucas A
• Smith Shane T

Classifications

• B60B2900/561

  Lubrication · CPC title

• F16H57/0434 Primary

  relating to lubrication supply, e.g. pumps; Pressure control · CPC title

• B60K17/36 Primary

  for driving tandem wheels · CPC title

• F16H57/0483

  Axle or inter-axle differentials · CPC title

• F16H57/0447 Primary

  Control of lubricant levels, e.g. lubricant level control dependent on temperature · CPC title