CONTROL VALVE FOR AN ANTI-LOCK BRAKE SYSTEM

摘要

A control valve in a vehicle anti-lock braking system for controlling the application of pressurized brake fluid to a selected brake has an outer housing with an inlet for the fluid and an outlet for supplying the fluid to the selected vehicle brake and a passageway connecting the inlet to the outlet. A normally open isolation valve in the passageway is movable between a normally open position wherein fluid can flow from the inlet to outlet and a closed position wherein fluid is prevented from flowing from the inlet to the outlet, the valve means being biased towards the open position. A solenoid responsive to a control signal moves the valve from the open to the closed position, the valve and the housing cooperating to define a chamber containing brake fluid and varying in volume as the valve is moved from the closed to the open position. A hydraulic damper restricts fluid flow between the passageway and the chamber for damping the movement of the valve means, whereby the opening of the valve means is precisely controlled.