Patent ID: 6024423
Filing Date: 2000-02-15
Classification: B60T

Abstract:
A braking system comprising:a wheel brake;a master cylinder;a modulator interposed in the braking system and interconnected with the wheel brake and the master cylinder so that fluid pressurization effected in the braking system by the master cylinder is communicated to the wheel brake through the modulator;an isolation valve positioned in the modulator and defining a primary flow path for normally permitting an unrestricted fluid flow and pressure exchange between the master cylinder and the wheel brake through the modulator and being operable to prevent fluid flow along the primary flow path from the master cylinder to the wheel brake by movement of a moveable element in the isolation valve;a solenoid valve associated with the modulator and being normally closed and being openable so that fluid pressure is released from the wheel brake through the solenoid valve and substantially simultaneously, the moveable element of the isolation valve moves t close the isolation valve to isolate the wheel brake from the master cylinder; anda flow regulating valve in the modulator having a compensating piston that automatically moves to provide a substantially consistent flow rate through the flow regulating valve wherein the flow regulating valve has an upstream side that receives fluid pressure and a downstream side that is in fluid communication with the solenoid valve wherein the solenoid valve is sized to accept fluid flow during an ABS release cycle from both the wheel brake to reduce fluid pressure therein and from the flow regulating valve so that flow through the flow regulating valve does not increase fluid pressure at the wheel brake wherein the flow regulating valve supplies fluid to the wheel brake during an ABS apply cycle at a tuned flow rate, wherein the flow regulating valve is connected in a parallel relationship with the isolation valve to provide a secondary flow path around the isolation valve.