Patent ID: 8342618

Claim:
A traction control device for a vehicle, comprising: an electric motor that is coupled to a driving wheel of the vehicle and is capable of carrying out a regenerative operation to produce a regenerative torque; and a means for detecting occurrence of a slippage of said driving wheel, the slippage occurring when a rotational speed of the driving wheel exceeds a speed of the vehicle, the traction control device for the vehicle being configured so that, when the occurrence of the slippage of said driving wheel is detected, the traction control device makes said electric motor produce the regenerative torque to apply a braking force to the driving wheel, thereby suppressing the slippage of the driving wheel, the traction control device further including: electric motor controlling means for controlling the regenerative torque produced by said electric motor in a variable manner when the occurrence of the slippage of said driving wheel is detected, the controlling occurring based on a determined value indicative of a road surface condition, the determined value used as an index parameter to a predetermined amount of regenerative torque, the amount of regenerative torque increasing in slippery road surface conditions; and means for detecting or estimating the acceleration of said vehicle, wherein, in a period in which said electric motor produces the regenerative torque, said electric motor controlling means uses said detected or estimated acceleration as said determined value, wherein, after the occurrence of the slippage of said driving wheel is detected, in a period from the point in time when the rotational speed of the driving wheel increases and exceeds a predetermined first threshold until the rotational speed of the driving wheel decreases to a predetermined second threshold after reaching a peak value, said electric motor produces the regenerative torque while controlling the regenerative torque in a variable manner according to the value of said index parameter, and, after a detection of the rotational speed of the driving wheel decreasing to be equal to or lower than the predetermined second threshold, the regenerative torque is stopped and the electric motor changes to a power running operation.