Torque distribution control device

A torque distribution control device for a vehicle having two laterally opposed wheels, two output shafts respectively connected to the wheels to rotate therewith, and an input shaft for supplying an engine torque to the output shafts, comprising:

• a first rotational speed differential responsive type control coupling disposed between the input shaft and one of the output shafts;
• a second rotational speed differential responsive type control coupling disposed between the input shaft and the other of the output shafts;
• said first and second control couplings each having various transfer torque characteristics and being operable to select one of said transfer torque characteristics in response to a signal supplied thereto;
• turning direction detecting means for detecting a turning direction of the vehicle and producing a signal representative thereof;
• vehicle speed detecting means for detecting a vehicle speed and producing a signal representative thereof;
• turning radius computing means for computing a turning radius and producing a signal representative thereof;
• target rotational speed differential computing means responsive to the signals from said vehicle speed detecting means and said turning radius computing means for computing a target rotational speed differential between the wheels which allows for turning without slip between tire and road surface, on the basis of the vehicle speed and the turning radius;
• and
• control means for supplying to an outer wheel side one of said control couplings, which outer wheel side one is determined on the basis of the signal from said turning direction detecting means, a signal for selecting one of said transfer torque characteristics that can produce a maximum transfer torque for a given rotational speed differential and for supplying to an inner wheel side one of said control couplings a signal for selecting, when said target rotational speed differential is obtained, one of said transfer torque characteristics that can produce a transfer torque equal to that produced by the outer wheel side one of said control couplings.