Arrangement for the propulsion regulation of motor vehicles

An arrangement for the propulsion regulation in the sense of reducing undesired slippages of the wheels to be regulated in motor vehicles equipped with four-wheel drive, comprising sensor means for determining the movement condition of the wheels, said sensor means producing rotational speed signals which are prepared into velocity signals in a signal preparation circuit means, means for forming a velocity reference signal to which are fed the velocity signals as also a signal of a transmitter means taking into consideration the vehicle longitudinal acceleration, comparator circuit means in which the reference signal is compared with velocity signals from the signal preparation circuit means and which produces an output signal when a velocity signal is greater than the reference signal, the output of the comparator circuit means being operatively connected with an AND-element which, in its turn, is connected with its output to an adjusting means for controlling the driving torque of the vehicle engine, all vehicle velocity signals prepared from the rotational speed signals being fed to the reference-signal-forming means and to the comparator circuit means as also to a differentiating element, the reference-signal-forming means initially forming the reference signal having a predetermined slope, from the velocity signal corresponding to the mimimum wheel velocity, the comparator circuit means producing an output signal when a velocity signal exceeds the reference signal by a predetermined difference which initiates at the adjusting means by way of the AND-element a first regulating cycle for the reduction of the driving torque of the vehicle engine, a blocking signal being present in the output of the differentiating element when a negative acceleration value derived from the velocity signal exceeds a predetermined negative acceleration value, said blocking signal being fed, on the one hand, to an inverting input of the AND-element whereupon the output thereof blocks, and on the other, effects at the adjusting means the keeping constant of the driving torque during the regulating cycle phase of the negative acceleration, upon the disappearance of the blocking signal, when the negative acceleration value falls below the predetermined negative acceleration value, the adjusting means being operable again to increase the driving torque in the direction toward a value specified by a drive pedal, and the reference signal-forming means being operable during the regulating cycle phase of the negative acceleration when the velocity signal drops below the reference signal, to correct the reference signal to the velocity signal corresponding to a smaller minimum wheel velocity with a new slope for the following regulating cycle.