Skid control system

Abstract

A low cost skid control system is disclosed that incorporates a skid detector circuit for detecting a skid condition in combination with a hold capacitor ramp circuit that maintains the brake release signal beyond the termination of the skid signal from the output of the detector circuit when a severe skid condition is encountered. The level of charge on the hold capacitor ramp circuit is adapted to relate to the severity of the wheel speed departure from the approximated vehicle speed. In one embodiment, this is accomplished indirectly by providing a peak acceleration circuit which stores the maximum wheel acceleration value attained during wheel spin-up when brake pressure is relieved. The peak acceleration value is then utilized to vary the charge rate of the hold-on capacitor during the succeeding braking period. In addition, another circuit is provided that is adapted to rapidly dissipate any remaining charge on the hold-on capacitor when the acceleration of the wheels during wheel spin-up begins to decrease. This helps minimize stopping distance by preventing the release of brake pressure beyond that necessary to complete wheel spin-up.