Switchable fast-fill hydraulic circuit for use in vehicle braking systems

摘要

An antilock/traction control/vehicle stability braking system hydraulic circuit using a fluid flow intensifier to provide a rapid application of fluid pressure to brakes during a TC/vehicle stability control operation at a flow rate that is greater than is normally available from an ABS pump alone. The intensifier increases the fluid flow as a function of using a stepped piston operating within respective input and output chambers having different effective diameters. The intensifier also includes an intermediate chamber into which fluid dumped from a brake cylinder is drawn rather than being lost to a master cylinder reservoir. The fluid thus remains in the hydraulic circuit, ensuring that a desired ratio of pedal travel versus pressure is maintained after a transition from TC/vehicle stability braking to ABS-base braking.