Apparatus and method for evacuation of a brake system
AssigneeZF Active Safety US Inc.
InventorsDouglas Osborn, Daniel L. Hopper
Life of this patent
Estimating the term…
Abstract
A method of operating a vehicle brake system having multiple wheel brakes includes providing a plunger assembly having a plunger and a chamber fluidly connected to at least one of the wheel brakes. An evacuation of at least one of the wheel brakes is performed by moving the plunger relative to the chamber under control of an electronic control unit (ECU) to generate a vacuum from the chamber to the at least one wheel brake. Pressurized brake fluid is supplied from a reservoir to the evacuated wheel brakes by moving the plunger relative to the chamber under control of the ECU once all the wheel brakes are evacuated.
Claims18
A method of operating a vehicle brake system having multiple wheel brakes, the method comprising:
- providing a plunger assembly having a plunger and a chamber fluidly connected to at least one of the wheel brakes;
- performing an evacuation of at least one of the wheel brakes by moving the plunger relative to the chamber under control of an electronic control unit (ECU) to generate a vacuum from the chamber to the at least one wheel brake;
- the evacuation comprising:
- a) advancing the plunger to exhaust a flow path between the plunger assembly and a master cylinder and through a three-way valve in a first condition;
- b) retracting the plunger while the three-way valve is in a second condition;
- and
- c) repeating steps a) and b) in an alternating manner until the at least one wheel brake falls below a predetermined pressure;
- and
- supplying pressurized brake fluid from a reservoir to the evacuated wheel brakes by moving the plunger relative to the chamber under control of the ECU once all the wheel brakes are evacuated.
A method of operating a vehicle brake system having multiple wheel brakes, the method comprising:
- providing a plunger assembly having a plunger and a chamber fluidly connected to at least one of the wheel brakes;
- performing an evacuation of at least one of the wheel brakes by moving the plunger relative to the chamber under control of an electronic control unit (ECU) to generate a vacuum from the chamber to the at least one wheel brake, wherein performing the evacuation comprises:
- a) advancing the plunger to exhaust a flow path between the plunger assembly and a master cylinder and through a three-way valve in a first condition;
- and then
- b) retracting and advancing the plunger multiple times in an alternating manner while the three-way valve is in a second condition until the at least one wheel brake falls below a predetermined pressure;
- and
- supplying pressurized brake fluid from a reservoir to the evacuated wheel brakes by moving the plunger relative to the chamber under control of the ECU once all the wheel brakes are evacuated.
Dependencies are inferred from the claim text.