Driving-force distribution control device

A driving-force distribution control device comprising:

• a driving force distribution mechanism for variably distributing a driving force from an engine to each drive wheel, the driving force distribution mechanism having a front and rear wheel driving force distribution mechanism that changes a driving force distribution of front and rear wheels of the vehicle, and a left and right wheel driving force distribution mechanism that changes a driving force distribution of left and right wheels of the vehicle;
• a driving force distribution controller that controls the driving force distribution mechanism in response to a running state of a vehicle, driving force distribution controller having a plurality of control modes including rotation seed difference control for controlling the driving force distribution mechanism by a control amount that corresponds to a rotation speed difference between at least one group of wheels selected from groups of the front and rear wheels, and left and right wheels;
• an anti-skid brake system that controls a braking state of the each wheel so that a slip state of each wheel of the vehicle is turned into a suitable state during braking;
• an acceleration detector that detects front and rear accelerations, and a lateral acceleration of the vehicle;
• a synthesized acceleration calculator that calculates a synthesized acceleration obtained based on the detected front and rear accelerations, and the detected lateral acceleration;
• a control coefficient setter that continuously sets a control coefficient for restricting a control amount of the driving force distribution controller during an operation of the anti-skid brake system in response to the calculated synthesized acceleration, the control coefficient setter continuously increasing a control coefficient, as the calculated synthesized acceleration increases, for each of the front and rear wheel driving force distribution mechanism and the left and right wheel driving force distribution mechanism, and continuously increasing a control coefficient, as the calculated synthesized acceleration increases, for each of the plurality of control modes to reduce priority of control for the anti-skid brake system, and at least decreasing the control coefficient to restrict a control amount of the rotational speed difference control during the operation of the anti-skid brake system as a whole as compared with other control mode, as the calculated synthesized acceleration increases;
• and
• the driving force distribution controller obtaining the control amount of the driving force distribution mechanism for each of the front and rear wheel driving force distribution mechanism and the left and right wheel driving force distribution mechanism based on the control coefficient obtained for each of the front and rear wheel driving force distribution mechanism and the left and right wheel driving force distribution mechanism, controlling the front and rear wheel driving force distribution mechanism and the left and right wheel driving force distribution mechanism, respectively, based on the obtained control amount, calculating an output value for each of the plurality of control modes based on the control coefficient obtained for each of the plurality of control modes, obtaining a control amount of the driving force distribution mechanism based on the calculated output value, and controlling the driving force distribution mechanism based on the obtained control amount.