PURPOSE: To judge a split road quickly and correctly and to enable sure spin restraint.
CONSTITUTION: An antiskid brake device of a vehicle comprises a total pressure reducing duration detecting means 55 for detecting the total pressure reducing duration of brake oil pressure after the operation of an oil pressure adjusting means 53 is starated, a continuous pressure reducing time detecting means 56 for detecting the pressure reducing time for each time, and a counter signal output means 57 for outputting a counter signal for each wheel when the total pressure reducing duration on each wheel side is above a designated value or when the continuous pressure reducing time is above a designated value. The device further comprises an integrating means 58 for integrating a positive unit integrated value in the case of a counter signal corresponding to one wheel side and a negative unit integrated value in the case of a counter signal corresponding to the other wheel side so as to set up an accumulated, value, and a split road judging means 59 for judging to be a split road in the case where the accumulated of the intergrating means 58 is other than 0 and judging which wheel side is a low μ road according to the positive or negative accumulated values.
HAYABUCHI KENSUKE
IZUMI TOMOMI
TATEHATA TETSUYA
MAZDA MOTOR