Torque distribution control device for four-wheel drive vehicle

A torque distribution control device for a four-wheel drive vehicle having a torque distribution device for distributing the drive power transmitted from an engine to prime drive wheels, to sub-drive wheels, said control device comprising abnormality judgment means for judging whether or not an abnormality is involved in wheel speed signals relating to said prime drive wheels and said sub-drive wheels;

• normal-state torque setting means for setting a command torque based on a vehicle speed, a throttle opening degree and a wheel speed difference between said prime drive wheels and said sub-drive wheels if said abnormality judgment means judges that no abnormality is involved in said wheel speed signals;
• abnormal-state torque setting means for setting said command torque based on said throttle opening degree only if said abnormality judgment means judges that an abnormality is involved in said wheel speed signals;
• and distribution torque setting means for outputting to said torque distribution device a command value depending on said command torque set by said normal-state torque setting means or said abnormal-state torque setting means.

A torque distribution control device for a four-wheel drive vehicle having a torque distribution device for distributing the drive power transmitted from an engine to prime drive wheels, to sub-drive wheels, said control device comprising abnormality judgment means for judging whether or not an abnormality is involved in wheel speed signals relating to said prime drive wheels and said sub-drive wheels;

• normal-state torque setting means for setting a command torque based on a vehicle speed, a throttle opening degree and a wheel speed difference between said prime drive wheels and said sub-drive wheels if said abnormality judgment means judges that no abnormality is involved in said wheel speed signals;
• abnormal-state torque setting means for setting said command torque based on a predetermined fixed value if said abnormality judgment means judges that an abnormality is involved in said wheel speed signals;
• and distribution torque setting means for outputting to said torque distribution device a command value depending on said command torque set by said normal-state torque setting means or said abnormal-state torque setting means.

A torque distribution control device for a four-wheel drive vehicle capable of controlling a command torque in distributing the drive power from an engine of said four-wheel drive vehicle to sub-drive wheels, in dependence on the traveling state of said vehicle, said control device comprising wheel speed detection means for detecting the wheel speed of each of four wheels including said sub-drive wheels;

• and command torque calculation means for calculating said command torque by the use of wheel speed data which said wheel speed detection means detects for each of said four wheels;
• wherein when an abnormality is involved in any one of wheel speed signals of either front wheels or rear wheels detected by said wheel speed detection means, the command torque calculation means replaces wheel speed data of the abnormal wheel speed signal by wheel speed data of a normal wheel speed signal of the wheel located opposite in the left-right direction and employs the replaced normal wheel speed data to calculate said command torque.