Patent ID: 6161906
Filing Date: 2000-12-19
Classification: B60T

Abstract:
An anti-skid control system, comprising:wheel cylinders for giving braking force to wheels of a vehicle;a hydraulic pressure generating unit for generating a brake hydraulic pressure corresponding to a tread-on amount of a brake pedal and for giving the brake hydraulic pressure to said wheel cylinders;hydraulic pressure control valves disposed between said wheel cylinders and said hydraulic pressure generating unit for controlling the brake hydraulic pressure of said wheel cylinders;wheel speed sensors for detecting rotational speed of said wheels; andcontrol means for controlling said hydraulic pressure control valves so as to at least decompress or pulse-boost the brake hydraulic pressure of said wheel cylinders based on an output signal of said wheel speed sensors;tread-on amount detecting means for detecting the tread-on amount of said brake pedal; and said control means comprises:road surface change judging means for comparing a continuous run pulse number or a continuous run time of the pulse boost control with a preset value and for judging that the road surface has shifted from that of low coefficient of friction to that of high coefficient of friction when the continuous run pulse number or the continuous run time of the pulse boost control exceeds a preset value;duty ratio changing means for changing the duty ratio of the pulse boost control so as to increase the rate of boost time when said road surface change judging means has judged that the road surface shifted from that of low coefficient of friction to that of high coefficient of friction;pulse boost executing means for controlling said hydraulic pressure control valve so as to pulse-boost the brake hydraulic pressure of said wheel cylinders based on the duty ratio changed by said duty ratio changing means; andpreset value changing means for changing said preset value based on an output signal of said tread-on amount detecting means.