Patent ID: 7490690
Filing Date: 2009-02-17
Classification: B60K

Abstract:
1. A control device for a front-and-rear wheel drive vehicle for electrically controlling a driving power transmission device which is arranged on a driving power transmission path of said vehicle for transmitting the drive power from a power source to driven wheels as either of front wheels and rear wheels of said vehicle, said control device including: switching control means for electrically controlling said driving power transmission device to switch the drive mode of said vehicle selectively from a two-wheel drive mode to a four-wheel drive mode; means for determining a difference between a present torque which said driving power transmission device is transmitting and a target torque which said driving power transmission device is to transmit after the switching of said drive mode from a two-wheel drive mode to a four-wheel drive mode; and gradual switching control means responsive to said difference determining means for electrically controlling said driving power transmission device to gradually change the present torque to the target torque only when the difference between said present and target torques is more than a predetermined value at the time of the switching of said drive mode from a two-wheel drive mode to a four-wheel drive mode.