BRAKE PRESSURE APPLY

• US 20080001477A1
• Filed: 06/30/2006
• Published: 01/03/2008
• Est. Priority Date: 06/30/2006
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Mattson, Keith, Salmon, Thomas A., Lavoie, Erick
• Granted Patent: US 8,602,508 B2
• Time in Patent Office: Days
• US Class Current: 303/191
• CPC Class Codes: B60T 13/12 the fluid being liquid
• CPC Class Codes: B60T 2201/122 Pre-actuation in case of ESP control
• CPC Class Codes: B60T 2230/03 Overturn, rollover
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02

Abstract

A method for brake pressure apply in a hydraulic brake system includes commanding a cage clearance reduction phase and commanding a wheel control phase subsequent to the cage clearance reduction phase. Accordingly, the cage clearance is reduced prior to entering the wheel control phase. A method for cage clearance reduction in a hydraulic brake system for roll stability control is also provided.

Claims

1. A method for brake pressure apply in a hydraulic brake system comprising:

commanding a cage clearance reduction phase; and

commanding a wheel control phase subsequent to the cage clearance reduction phase,

wherein the cage clearance is reduced prior to said commanding of the wheel control phase.

2. The method of claim 1 wherein the cage clearance reduction phase and the wheel control phase are initiated during a roll stability control (“

RSC”

).

3. The method of claim 2 further comprising determining whether the RSC is complete.

4. The method of claim 3 further comprising determining whether an inertial phase is exceeded when the RSC is not complete.

5. The method of claim 4 wherein said commanding is in response to said determining whether the inertial phase is exceeded.

6. The method of claim 1 further comprising determining whether an inertial phase is exceeded.

7. The method of claim 6 wherein said commanding is in response to said determining.

8. The method of claim 6 wherein said commanding the wheel control phase is in response to said determining that the inertial phase is not exceeded.

9. A method for brake pressure pulsing to achieve cage clearance reduction in a hydraulic brake system command comprising:

performing a cage clearance reduction, the cage clearance reduction comprises commanding at least one pressure build and commanding at least one pressure release; and

commanding a wheel control in response to performing the cage clearance reduction,

wherein a pressure command during the wheel control phase experiences refined pressure estimate and reduced cage clearance.

10. The method of claim 9 further comprising determining whether an inertial phase is exceeded before commanding a wheel control.

11. The method of claim 9 wherein the at least one pressure build and the at least one pressure release are based upon a RSC pressure control estimate.

12. The method of claim 9 further comprising determining whether cage clearance is minimized after the at least one pressure build or the at least one pressure release.

13. The method of claim 9 further comprising determining whether the wheel control is required after the at least one pressure build or the at least one pressure release.

14. A method for cage clearance reduction in a hydraulic brake system for roll stability control comprising:

performing a pressure build based upon a pressure control estimate; and

performing a pressure release based upon the pressure control estimate;

wherein cage clearance is substantially minimized by said commanding prior to entering a wheel control phase.

15. The method of claim 14 further comprising repeating performing.

16. The method of claim 14 further comprising determining whether cage clearance is minimized.

17. The method of claim 16 wherein performing is in response to determining.

18. The method of claim 14 further comprising determining whether the wheel control phase is required.

19. The method of claim 14 wherein the pressure build is a step function.

20. The method of claim 14 wherein the pressure release is a step function.