System and method for increasing regenerative braking in a rear-wheel-drive-based platform with four-wheel-drive capability

Patent metadata

Field	Value
Publication number	US-11225238-B2
Application number	US-201514714687-A
Country	US
Kind code	B2
Filing date	May 18, 2015
Priority date	May 18, 2015
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

A vehicle includes a power source configured to provide drive torque, a front axle, a rear axle, and a transfer case configured to distribute drive torque from the power source between the front axle and the rear axle. The vehicle additionally includes a clutch arranged between the front axle and the transfer case. The clutch has a disengaged state and an engaged state drivingly coupling the transfer case and the front axle. The vehicle also includes a regenerative braking system configured to, in response to a braking request, provide regenerative braking torque to the rear axle. The vehicle further includes a controller. The controller is configured to, in response to a braking request and the clutch being in the disengaged state, control the clutch to shift into the engaged state to couple the regenerative braking system to the front axle and provide regenerative braking torque to the front axle.

First claim

What is claimed is:

1. A vehicle comprising:
a power source configured to provide drive torque;
a front axle;
first and second wheels arranged on the front axle;
a rear axle;
a transfer case configured to distribute drive torque from the power source between the front axle and the rear axle;
a front differential drivingly coupling the transfer case and the front axle;
a first disconnect arranged between the front differential and the first wheel configured to drivingly couple the front differential and the first wheel when engaged;
a second disconnect arranged between the front differential and the second wheel and configured to drivingly couple the front differential and the second wheel when engaged;
a clutch arranged between the front axle and the transfer case, the clutch having an engaged state and a disengaged state, wherein in the engaged state the clutch drivingly couples the transfer case and the front axle;
a regenerative braking system configured to, in response to a braking request, provide regenerative braking torque to the rear axle; and
a controller configured to, in response to the braking request exceeding a corresponding threshold and the clutch being in the disengaged state, control the clutch to shift into the engaged state to couple the regenerative braking system to the front axle and control the first and second disconnects to engage to provide regenerative braking torque to the front axle, and to control at least one of the clutch and the first and second disconnects to disengage in response to the braking request not exceeding the corresponding threshold.

2. The vehicle of claim 1 , further comprising a battery electrically coupled to the regenerative braking system and having a state of charge, wherein the controller is configured to control the clutch to engage in further response to the state of charge being below an associated threshold.

3. The vehicle of claim 1 , wherein the regenerative braking system comprises an electric machine.

4. A method of controlling a vehicle having a power source configured to supply drive torque to a rear axle, a regenerative braking system configured to apply regenerative braking torque to the rear axle, and a shiftable member configured to selectively drivingly couple the power source to a front axle, the method comprising:
in response to a braking request exceeding a threshold, temperature of at least one powertrain component satisfying a predetermined durability requirement, and the shiftable member being disengaged, engaging the shiftable member to apply regenerative braking torque to the front axle.

5. The method of claim 4 , wherein the shiftable member includes a clutch arranged between a transfer case and a front differential drivingly coupled to the front axle, and wherein engaging the shiftable member includes controlling the clutch to engage to drivingly couple the transfer case and the front differential.

6. The method of claim 4 , wherein the shiftable member includes a clutch arranged between a front wheel and a front differential drivingly coupled to the front axle, and wherein engaging the shiftable member includes controlling the clutch to engage to drivingly couple the front differential and the front wheel.

7. The method of claim 4 , wherein the engaging the shiftable member is in response to the braking request exceeding an associated threshold.

8. The method of claim 7 , further comprising, in response to the braking request falling below the associated threshold, disengaging the shiftable member.

9. A vehicle comprising:
front and rear wheels
regenerative brakes configured to, in response to a braking request, apply regenerative braking torque to the rear wheels;
a shiftable member configured to selectively couple the regenerative brakes to the front wheels; and
a controller configured to, in response to a braking request exceeding a threshold, temperature of the shiftable member satisfying a predetermined durability requirement, and the shiftable member being disengaged, control the shiftable member to engage.

10. The vehicle of claim 9 , further comprising a transfer case arranged between the front wheel and the rear wheel and configured to distribute torque among the front wheel and rear wheel, wherein the shiftable member includes a clutch configured to, when engaged, drivingly couple the transfer case and the front wheel.

11. The vehicle of claim 10 , further comprising a front differential configured to drive the front wheel and a drive shaft drivingly coupled to the front differential, wherein the clutch is arranged between the transfer case and the drive shaft and configured to, when engaged, drivingly couple the transfer case and the drive shaft.

12. The vehicle of claim 10 , further comprising a front differential configured to drive the front wheel and a drive shaft drivingly coupling the front differential and the transfer case, wherein the clutch is arranged between the front differential and the wheel and configured to, when engaged, drivingly couple the front differential and the wheel.

13. The vehicle of claim 9 , wherein the controller is configured to control the shiftable member to engage in further response to a battery state of charge being below an associated threshold.

14. The vehicle of claim 9 , wherein the regenerative brakes comprise an electric machine.

Assignees

• Ford Global Tech Llc

Inventors

• Lauffer Scott J
• Rodrigues Ashok E
• Crombez Dale Scott
• Perakes Andreas E
• Tomik Filip
• Kootsillas Kevin
• Lindlbauer Michael Paul

Classifications

• B60L7/10

  Dynamic electric regenerative braking (B60L7/22 takes precedence) · CPC title

• B60K23/08

  for changing number of driven wheels {, for switching from driving one axle to driving two or more axles (B60K17/3515 takes precedence)} · CPC title

• B60W30/1843

  Overheating of driveline components (B60W30/186 takes precedence) · CPC title

• B60W30/18127

  Regenerative braking · CPC title

• B60W10/119

  including control of all-wheel-driveline means, e.g. transfer gears or clutches for dividing torque between front and rear axle (B60W10/14 takes precedence) · CPC title