Patent ID: 6497301
Filing Date: 2002-12-24
Classification: B60K,B60W

Abstract:
A front/rear wheel torque distribution control apparatus of a four-wheel drive vehicle having an electronic control clutch for controlling a torque distribution to front and rear wheels, in which one of the front and rear wheels is a main drive wheel and the other is a subsidiary drive wheel, said front/rear wheel torque distribution control apparatus comprising:a tire diameter difference degree detector for detecting a degree of a diameter difference between a different-diameter tire and a normal-diameter tire when any of the front and rear wheels mounts the different-diameter tires; a driver request torque calculator for calculating a driver request torque transmitted from the main drive wheel to the subsidiary drive wheel via said electronic control clutch in response to an operation of a driver; a vehicle speed detector for detecting a vehicle speed; a starting time limit speed determiner for making a starting time limit speed in which a torque at the time of starting of the vehicle is limited by a vehicle speed lower as the degree of the diameter difference detected by said tire diameter difference degree detector is larger; and a starting time torque distribution controller for outputting an instruction to obtain the driver request torque calculated by said driver request torque calculator to the electronic control clutch until the vehicle speed becomes equal to a starting time limit vehicle speed determined by said starting time limit vehicle speed determiner when the vehicle mounts the different-diameter tires.