Anti-skid control system for vehicle

An anti-skid brake control system for a vehicle comprising

• a wheel speed detecting means which detects the speeds of wheels of the vehicle,
• a deceleration detecting means which detects the deceleration of the vehicle,
• a first estimated vehicle speed calculating means which calculates a first estimated vehicle speed on the basis of the highest of the speeds of the wheels as detected by the wheel speed detecting means and the deceleration of the vehicle as detected by the deceleration detecting means,
• a second estimated vehicle speed calculating means for calculating a second estimated vehicle speed which begins to reduce from a predetermined value at a predetermined rate independent from the change in the highest of the speeds of the wheels from the time the first estimated vehicle speed as calculated by the first estimated vehicle speed calculating means falls to the predetermined value,
• a selecting means which adopts the first estimated vehicle speed as a final estimated vehicle speed when the first estimated vehicle speed is not lower than the predetermined value and adopts the second estimated vehicle speed as the final estimated vehicle speed when the first estimated vehicle speed is lower than the predetermined value,
• a slip ratio calculating means which calculates the slip ratio of each wheel on the basis of the final estimated vehicle speed determined by the selecting means and the speed of the wheel as detected by the wheel speed detecting means, and
• a braking force control means which controls the braking force applied to each wheel so that the slip ratio of the wheel as calculated by the slip ratio calculating means converges on a target slip ratio.