Method for operating an electromechanical vehicle brake system

• US 9,592,812 B2
• Filed: 06/12/2015
• Issued: 03/14/2017
• Est. Priority Date: 06/13/2014
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Svensson, Thomas, Jurkiw, Tim
• Primary Examiner(s): Beaulieu, Yonel
• Application Number:
  US14/738,676
• Publication Number:
  US 20150360663A1
• Time in Patent Office: 641 Days
• US Class Current: 1/1
• CPC Class Codes: B60T 13/745 acting on a hydraulic system, e.g. a master cylinder
• CPC Class Codes: B60T 2201/10 Automatic or semi-automatic parking aid systems
• CPC Class Codes: B60T 2201/12 Pre-actuation of braking systems without significant braking effect; Optimizing brake performance by reduction of play between brake pads and brake disc
• CPC Class Codes: B60T 2210/14 Rough roads, bad roads, gravel roads
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: B60T 8/171 Detecting parameters used in the regulation; Measuring values used in the regulation
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: B60T 8/3255 Systems in which the braking action is dependent on brake pedal data
• CPC Class Codes: B60T 8/3275 Systems with a braking assistant function, i.e. automatic full braking initiation in dependence of brake pedal velocity
• CPC Class Codes: B60T 8/4872 pump-back systems

Abstract

A method for operating an electromechanical vehicle brake system is provided. The method includes determining that an activation condition has been met, selecting a pre-charge pressure based at least in part on the activation condition, building up at least an initial portion of the pre-charge pressure in the brake system, and applying at least the initial portion of the pre-charge pressure to at least one wheel brake.

Claims

1. A method for operating an electromechanical vehicle brake system, comprising:

in advance of a braking request, determining that an activation condition has been met;

selecting a pre-charge pressure based at least in part on the activation condition;

building up at least an initial portion of the pre-charge pressure in the brake system; and

applying at least the initial portion of the pre-charge pressure to at least one wheel brake.

2. The method as claimed in claim 1, wherein determining that an activation condition has been met includes calculating a rate of release of an accelerator pedal.

3. The method as claimed in claim 1, wherein determining that an activation condition has been met includes receiving a signal indicative of a detected object.

4. The method as claimed in claim 3, wherein receiving a signal indicative of a detected object includes receiving a signal from a collision warning device of the vehicle.

5. The method as claimed in claim 1, wherein determining that an activation condition has been met includes receiving an instruction to initiate an automatic parking process.

11. The method as claimed in claim 3, further comprising building up a secondary pre-charge pressure after applying the initial portion of the pre-charge pressure to the wheel brakes.

12. The method as claimed in claim 11, further comprising closing a valve device which is arranged upstream of the wheel brake prior to building up the secondary portion of the pre-charge pressure.

17. The method as claimed in claim 1, further comprising providing a remaining portion of the pre-charge pressure to the wheel brakes upon receipt of a braking request.

18. The method of claim 17, wherein the braking request is a manual deceleration request or an autonomous deceleration request.

19. The method of claim 1, wherein building up at least an initial portion of the pre-charge pressure includes building up an entirety of the selected pre-charge pressure, and wherein applying at least the initial portion of the pre-charge pressure to the wheel brakes includes passing substantially all of the pre-charge pressure on to the wheel brake during the buildup of said pre-charge pressure.

20. The method of claim 19, further comprising maintaining at least one of the initial portion of the pre-charge pressure and the secondary portion of the pre-charge pressure in the brake system for a period of time, wherein the respective level of the pre-charge pressure and/or the period of time for the maintenance of the pre-charge pressure is calculated as a function of an external condition and/or the activity of a windshield wiper device of the vehicle.

21. The method of claim 20, further comprising reducing the pre-charge pressure in the brake system when the period of time for the maintenance of the pre-charge pressure expires.

22. The method as claimed in claim 1, further comprising building up a secondary pre-charge pressure after applying the initial portion of the pre-charge pressure to the wheel brakes.

23. The method of claim 22, further comprising closing a valve device which is arranged upstream of the wheel brake prior to building up the secondary portion of the pre-charge pressure.

6. A method for operating an electromechanical vehicle brake system, comprising:

determining that an activation condition has been met;

selecting a pre-charge pressure based at least in part on the activation condition;

building up at least an initial portion of the pre-charge pressure in the brake system;

applying at least the initial portion of the pre-charge pressure to at least one wheel brake; and

providing a remaining portion of the pre-charge pressure to the wheel brakes upon receipt of a braking request.

7. The method as claimed in claim 6, wherein the braking request is a manual deceleration request or an autonomous deceleration request.

8. The method as claimed in claim 6, wherein building up at least an initial portion of the pre-charge pressure includes building up an entirety of the selected pre-charge pressure, and wherein applying at least the initial portion of the pre-charge pressure to the wheel brakes includes passing substantially all of the pre-charge pressure on to the wheel brake during the buildup of said pre-charge pressure.

24. The method of claim 6, wherein determining that an activation condition has been met comprises at least one of calculating a release rate of an accelerator pedal, receiving a signal indicative of a detected object, and receiving an instruction to initiate an automatic parking process.

25. The method of claim 24, wherein receiving a signal indicative of a detected object comprises receiving a signal from a collision warning device of the vehicle.

9. A method for operating an electromechanical vehicle brake system, comprising:

determining that an activation condition has been met;

selecting a pre-charge pressure based at least in part on the activation condition;

building up at least an initial portion of the pre-charge pressure in the brake system;

applying at least the initial portion of the pre-charge pressure to at least one wheel brake; and

building up a secondary portion of the pre-charge pressure after applying the initial portion of the pre-charge pressure to the wheel brakes.

10. The method as claimed in claim 9, further comprising closing a valve device which is arranged upstream of the wheel brake prior to building up the secondary portion of the pre-charge pressure.

13. The method as claimed in claim 10, further comprising maintaining at least one of the initial portion of the pre-charge pressure and the secondary portion of the pre-charge pressure in the brake system for a period of time, wherein the respective level of the pre-charge pressure and/or the period of time for the maintenance of the pre-charge pressure is calculated as a function of an external condition and/or the activity of a windshield wiper device of the vehicle.

14. The method as claimed in claim 13, further comprising reducing the pre-charge pressure in the brake system when the period of time for the maintenance of the pre-charge pressure expires.

15. The method as claimed in claim 10, further comprising maintaining at least one of the initial portion of the pre-charge pressure and the secondary portion of the pre-charge pressure in the brake system for a period of time, wherein the respective level of the pre-charge pressure and/or the period of time for the maintenance of the pre-charge pressure is calculated as a function of an external condition and/or the activity of a windshield wiper device of the vehicle.

16. The method as claimed in claim 15, further comprising reducing the pre-charge pressure in the brake system when the period of time for the maintenance of the pre-charge pressure expires.

26. The method of claim 9, wherein determining that an activation condition has been met comprises at least one of calculating a release rate of an accelerator pedal, receiving a signal indicative of a detected object, and receiving an instruction to initiate an automatic parking process.

27. The method of claim 26, wherein receiving a signal indicative of a detected object comprises receiving a signal from a collision warning device of the vehicle.

28. An electromechanical vehicle brake system, comprising:

a controller configured to;

in advance of a braking request, determine that an activation condition has been met;

select a pre-charge pressure based at least in part on the activation condition;

build up at least an initial portion of the pre-charge pressure in the brake system; and

apply at least the initial portion of the pre-charge pressure to at least one wheel brake.

29. The electromechanical vehicle brake system of claim 28, wherein the controller is further configured to provide a remaining portion of the pre-charge pressure to the wheel brakes upon receipt of a braking request.

30. The electromechanical vehicle brake system of claim 28, wherein the controller is further configured to build up a secondary portion of the pre-charge pressure after applying the initial portion of the pre-charge pressure to the wheel brakes.