BRAKE PRESSURE APPLY

• US 20140067223A1
• Filed: 11/09/2013
• Published: 03/06/2014
• 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: Lavoie, Erick Michael, Salmon, Thomas, Mattson, Keith Glenn
• Granted Patent: US 9,315,183 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• 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 pulsing to achieve cage clearance reduction in a hydraulic brake system comprising the steps of:

commanding a series of pressure builds and pressure releases while a measured brake pressure is greater than zero and until a brake system inertia is overcome; and

commanding a wheel control phase subsequent to commanding the series of pressure builds and releases.

2. The method of claim 1 further comprising determining that the brake system inertia has been overcome before commanding a wheel control.

3. The method of claim 1 wherein the series of pressure builds and pressure releases are based upon a brake pressure from a RSC system.

4. The method of claim 1 further comprising the step of determining whether cage clearance is minimized after at least one pressure build or at least one pressure release by comparing a measured brake pressure to a brake pressure from the RSC system.

5. The method of claim 4 further comprising the step of determining whether the wheel control phase is required after the at least one pressure build or the at least one pressure release by comparing a measured brake pressure to a brake pressure from the RSC system.

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

performing at least one pressure build while a measured brake pressure is greater than zero; and

performing at least one pressure release while the measured brake pressure is greater than zero;

wherein cage clearance is substantially minimized by said at least one pressure build and at least one pressure release while a measured brake pressure until a brake system inertia is overcome.

7. The method of claim 6 further comprising the step of repeating the steps of performing at least one pressure build and at least one pressure release while a measured brake pressure is greater than zero and until the brake system inertia is overcome.

8. The method of claim 7 further comprising the step of determining whether cage clearance is minimized by comparing a measured brake pressure to a brake pressure from the RSC system.

9. The method of claim 8 wherein the step of repeating the at least one brake pressure build and the at least on brake pressure release is in response to determining the cage clearance has not been minimized.

10. The method of claim 7 further comprising the step of determining whether the wheel control phase is required.

11. The method of claim 6 wherein the at least one pressure build is a step function.