Electronic locking differential

• US 10,451,161 B2
• Filed: 11/06/2017
• Issued: 10/22/2019
• Est. Priority Date: 11/06/2017
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Garcia, Gustavo Luis, Povirk, Jacob Martin, Guo, Jihong, Tomik, Filip
• Primary Examiner(s): Dang, Tinh T
• Application Number:
  US15/804,173
• Publication Number:
  US 20190136952A1
• Time in Patent Office: 715 Days
• CPC Class Codes: B62D 15/029 Steering assistants using warnings or proposing actions to the driver without influencing the steering system
• CPC Class Codes: F16H 2048/205 using the steering as a control parameter
• CPC Class Codes: F16H 48/24 using positive clutches or brakes
• CPC Class Codes: F16H 48/34 using electromagnetic or electric actuators

Abstract

A vehicle includes a differential having an electronic locker and a controller. The controller is programmed to, when in differential-lock mode, engage the locker responsive to vehicle speed being less than a speed threshold and a steering angle being less than a threshold, disengage the locker responsive to vehicle speed exceeding the speed threshold, and prevent automatic re-engagement of the locker responsive to the steering angle exceeding the threshold.

Claims

1. A vehicle comprising:

a differential including an electronic locker; and

a controller programmed to, when in differential-lock mode,

engage the locker responsive to vehicle speed being less than a speed threshold and a parameter indicative of steering angle being less than a threshold,

disengage the locker responsive to vehicle speed exceeding the speed threshold,

prevent automatic re-engagement of the locker responsive to the parameter exceeding the threshold, and

issue a driver alert, requesting straightening of the steering shaft, in response to the parameter exceeding the threshold.

2. The vehicle of claim 1, wherein the controller is further programmed to prevent automatic re-engagement of the locker further responsive to an accelerator-pedal position exceeding a threshold.

3. The vehicle of claim 1 further comprising a steering system including a sensor, wherein the parameter is a signal output from the sensor.

4. The vehicle of claim 1, wherein the speed threshold is between 15 and 30 miles per hour, inclusive.

5. The vehicle of claim 1 further comprising a display, and wherein the controller is further programmed to command the display to show an alert in response to the parameter exceeding the threshold.

6. The vehicle of claim 1 further comprising a steering shaft and the parameter includes an angle of the steering shaft.

14. The vehicle of claim 6, wherein the speed threshold is between 15 and 30 miles per hour, inclusive.

7. A vehicle comprising:

a differential including an electronic locker; and

a controller programmed to,

responsive to the locker being engaged and vehicle speed exceeding a speed threshold, command disengagement of the locker, and

responsive to the locker being disengaged, differential-lock mode being requested, vehicle speed being below the speed threshold, and a parameter indicative of a steering angle exceeding a threshold, (i) prevent automatic re-engagement of the locker and (ii) issue a driver alert.

8. The vehicle of claim 7, wherein the issue a driver alert includes requesting straightening of wheels.

9. The vehicle of claim 7 further comprising a display, and wherein the controller is further programmed to command the display to show the driver alert.

10. The vehicle of claim 7 further comprising an activation mechanism in electric communication with the controller, wherein differential-lock mode is requested by a user via the activation mechanism.

11. The vehicle of claim 7 further comprising a steering system including a sensor configured to output the parameter.

12. The vehicle of claim 7 further comprising a steering system including a steering shaft and a sensor configured to measure rotation of the steering shaft, wherein the parameter is a signal output by the sensor.

13. The vehicle of claim 12, wherein the parameter is indicative of an angular position of front wheels of the vehicle.

15. A method of controlling an electronic-locking differential comprising:

disengaging the electronic-locking differential responsive to the differential being engaged and vehicle speed exceeding a speed threshold;

preventing automatic re-engagement of the differential responsive to the differential being disengaged, differential-lock mode being requested, vehicle speed being below the speed threshold, and a parameter indicative of steering angle exceeding a threshold; and

displaying an alert to a driver in response to the parameter exceeding the threshold and the differential-lock mode being requested.

16. The method of claim 15, wherein the alert includes instructions to straighten wheels.