Propulsion control using longitudinal acceleration, steering angle, and speed to select slip threshold

Claim 1

In a propulsion control system for a motor vehicle for preventing an undesirable spinning of driven vehicle wheels, having a plurality of wheel sensor means for providing a signal indicative of the speed of the vehicle wheels, having slip means for determining the slip of the driven vehicle wheels from said signals of said sensor means, having a first slip comparator means for each driven vehicle wheel for comparing the driven wheel speed to a first indicated threshold value and providing an output signal when the first threshold is exceeded, having means for actuating a control element to reduce the output torque of an engine of the vehicle in response to an output signal indicative of at least one of the driven wheels of the vehicle tends to spin, having a vehicle speed comparator means for comparing vehicle speed to a third indicated threshold value and providing an output signal when the third threshold is exceeded, having a determining means for determining the longitudinal acceleration of the vehicle, having a longitudinal acceleration comparator means for comparing said longitudinal acceleration to a second indicated threshold value and providing an output signal when the second threshold is exceeded, having a steering angle sensor means for sensing steering angle and, having a steering angle comparator means for comparing said steering angle to a fourth indicated threshold value and providing an output signal when the fourth threshold is exceeded, the improvement comprising: two additional slip comparator means each for comparing the associated driven wheel speed to indicated threshold values, one of which has a lower and one has a higher threshold value with respect to said first indicated threshold value for each driven vehicle wheel and providing an output signal when the respective threshold is exceeded; an additional longitudinal acceleration comparator means for comparing said longitudinal acceleration to an indicated higher threshold value with respect to said second indicated threshold and providing an output when the higher threshold is exceeded; and a logic means for selectively enabling one of said first slip and said two additional slip comparator means in response to predetermined combinations of: (a) said output signal from the vehicle speed comparator means, (b) said output signal from one of the longitudinal acceleration comparator means, (c) said output signal from the steering angle comparator means as well as said input signal to the actuating means for the control element affecting the engine torque.