Patent ID: 7392875
Filing Date: 2008-07-01
Classification: B60K,B60W,Y02T

Abstract:
1. A four-wheel drive system for controlling driving of four wheels of a four-wheel drive vehicle where torque is distributable to front wheels and rear wheels, the system comprising: a slip sensing means for sensing a slip of rear wheels due to a spin thereof, and a torque correcting means for correcting a torque on the rear wheels so that a driving force of the rear wheels whose slip is sensed by the slip sensing means is reduced and then increased, wherein the torque correcting means operates to reduce the driving torque of the rear wheels until the driving torque reaches to a lower level where the slip is eliminated when the slip of the rear wheels is sensed, wherein the torque correcting means operates to keep the reduced driving torque until the slip is eliminated and then to increase the driving torque when the slip of the rear wheels is sensed, and wherein the torque correcting means, after eliminating the slip, operates to increase the driving torque lower than a value which the driving torque has taken at the time of occurrence of the slip.