IMPROVEMENTS IN ANTI-LOCK BRAKING SYSTEMS (ABS) FOR ROAD VEHICLES

摘要

An anti-skid braking system for wheeled vehicles having fluid actuated brakes associated with the vehicle wheels, comprising speed sensors associated with the vehicle wheels, a scanning control device response to speed signals from the speed sensors to actuate a pressure dump device to periodically release the fluid pressure applied to the brake of any wheel which is determined, by detection or a predetermined level of relative slip between that wheel and the road surface to be about to lock, and to later re-apply the actuating pressure to that brake when the tendency of that wheel to lock has reduced, and control means adapted (a) to adjust the magnitude of said predetermined level of relative slip to which said control device responds such as to reduce the slip sensitivity at the first sign of an impending skid condition, (b) to maintain the slip sensitivity at this level for a period corresponding to the time needed by the axle to move rapidly through its available deflection, and (c) to then restore the slip detection sensitivity to its normal level.