ANTISKID TYPE BRAKE-SYSTEM FOR FOUR WHEEL AUTOMOBILE

PURPOSE:To restrain the weight and cost of a brake device from increasing, by obtaining a travel speed of a vehicle in such a way that the rotational speed of an outside front wheel of the vehicle which is highest is neglected during turn of the vehicle to delay the time of initiation of antiskid control. CONSTITUTION:An antiskid type brake system has a control device which receives output signals from rotational speed sensors 44, 46, 48 for detecting the rotational speeds of left and right front wheels 10, 12 and a propeller shaft 50, and estimates the travel speed of a vehicle in accordance with the rotational speeds of those. Further, the control device estimates a slip condition for each wheel in accordance with the difference between the estimated travel speed and the rotational speeds of the wheels to control actuators 26, 28, 30 for increasing and decreasing the hydraulic pressures of brakes 18, 20, 22, 24. In this arrangement, when a turn sensor 52 detects such a condition that the vehicle is turning, the control device 42 estimates the travel speed of the vehicle such that the output signal of the rotational speed sensor 44 for the left front wheel 10 is neglected if the vehicle turns to the right while the output signal of the rotational speed sensor 46 for the light front wheel 12 is neglected if the vehicle turns to the left.