초록 ▼

An anti-skid control system includes a wheel speed calculation in which newly derived wheel speed is compared with a wheel speed derived at an immediately preceding calculation. When the newly derived instant wheel speed is different from the previously derived old wheel speed beyond a predetermined

An anti-skid control system includes a wheel speed calculation in which newly derived wheel speed is compared with a wheel speed derived at an immediately preceding calculation. When the newly derived instant wheel speed is different from the previously derived old wheel speed beyond a predetermined value which is variable in dependent upon variation of the wheel speed derived at the immediately preceding calculation. A back-up signal is derived and output as a replacement of wheel speed data. The back-up signal may have a value substantially corresponding to a wheel speed data avoiding error component in the instant wheel speed.

대표청구항 ▼

An anti-skid brake control system for an automotive hydraulic brake system comprising: a hydraulic brake circuit including a wheel cylinder for applying braking force to a vehicle wheel; a pressure control valve disposed within said hydraulic circuit and operative to increase fluid pressure in said

An anti-skid brake control system for an automotive hydraulic brake system comprising: a hydraulic brake circuit including a wheel cylinder for applying braking force to a vehicle wheel; a pressure control valve disposed within said hydraulic circuit and operative to increase fluid pressure in said wheel cylinder in a first position thereof, to decrease the fluid pressure in said wheel cylinder in a second position thereof and to hold the fluid pressure in said wheel cylinder constant in a third position thereof; a wheel speed sensor means for detecting the rotational speed of said vehicle wheel and producing sensor signal pulses separated by intervals; a timer means for producing timer signals having values representative of measured periods of time; a first means for sampling said timer signals in synchronism with said sensor signal pulses; a second means operatively connected with said first means for deriving wheel speed values from values of the sampled timer signals; a memory means operatively connected with said second means for storing at least the two most recently derived wheel speed values; a third means operatively connected to the memory means for receiving the stored derived wheel values for comparing the two most recently derived wheel speed values and producing a fault signal when the difference therebetween is greater than a predetermined value which is variable depending on the older wheel speed value among said two most recently derived wheel speed values; means operatively connected with said third means for deriving said predetermined value based on said older wheel speed value; a fourth means responsive to said fault signal for deriving a back-up signal having a value representative of an estimated actual wheel speed value and replacing the most recently derived wheel speed value with said back-up value; and a fifth means responsive to said wheel speed values and values of said sampled timer signals for producing a control signal which actuates said pressure control valve to one of said first, second and third positions so as to adjust the wheel rotational speed toward an optimal relationship with vehicle speed.