System for controlling the propulsion on motor vehicles

A system for controlling the propulsion on motor vehicles, to prevent undesired spinning of the driven vehicle wheels, comprising

• a first control loop means for reacting to the state of motion of at least one driven vehicle wheel to activate a wheel brake when a wheel is tending to spin,
• a second control loop means for causing the output torque of the drive unit to be reduced in the event of a tendency of driven wheels on both sides of the vehicle to spin,
• a measuring means for sensing the speed of the vehicle to generate an output signal which is characteristic of said speed,
• a first comparator means triggered by at least one presettable threshold value v.sub.s1 of the speed of the vehicle for generating the output signal which effects the reduction of the drive torque as soon as this threshold value is exceeded and a signal is present, which indicates that at least one of a wheel-brake is being activated and one of the driven wheels is tending to spin,
• wherein a second higher speed threshold-value v.sub.s2 is preset, and further comprising
• a v.sub.s2 comparator means for generating an output signal when the threshold value v.sub.s2 is being exceeded and as soon as only a single brake-control signal is present to indicate that one of the driven wheels is tending to spin,
• means responsive to the v.sub.s2 comparator means output-signal for causing the drive torque to be reduced,
• means for triggering the first comparator means by the first threshold value v.sub.s1 and
• means for activating the first comparator means in response to a sensing that the vehicle is following a curved path.