Abstract: A vehicle behavior control apparatus is disclosed. The vehicle behavior control apparatus comprises: a slip angle difference predicting section for predicting a difference between a slip angle of front wheels and a slip angle of rear wheels; a steer angle detecting section for detecting a steer angle of the vehicle; and a control section for controlling turning behaviors of the vehicle, based on an angle difference signal from said slip angle difference predicting section and a steer angle signal from said steer angle detecting section.

Abstract: An electric power steering apparatus having a motor for producing assist torque according to the steering torque, and a rack and pinion mechanism for transferring torque assistance to the rack shaft. The pinion and rack of the rack and pinion mechanism are both helical gears, and transfer high torque to the rack shaft. The helical gears have a curved arc tooth profile. The teeth of a curved arc tooth profile gear set mesh with contact between convex and concave surfaces. The contact area is therefore increased and contact pressure is decreased compared with involute teeth. Surface fatigue strength, bending strength, and bending fatigue strength are thus greater compared with involute teeth. The combined steering torque and assist torque is efficiently transferred to the rack shaft, and durability is sufficient to withstand torque loads from motor inertia.

Abstract: Electric power steering apparatus includes a control nit for controlling an electric motor to impart electric steering assist torque to the steering system of an automotive vehicle. The control unit is provided with a non-steady state detector section that generates a modification signal when it detects a non-steady state of the vehicle in which the steering wheel is turned to an excessive extent. Target motor current signal, which acts to impart the electric steering assist torque corresponding to manual steering torque, is modified by the control unit in accordance with the modification signal generated by the non-steady state detector section. Thus, the tire-to-steering-wheel torque is assisted in a returning direction of the steering wheel, so that the steering wheel is allowed to return to its center position at an increased speed.

Abstract: An electric power steering apparatus comprises a control unit for drive-controlling a motor to apply an assist torque to a steering system based on signals from various sensors. The control unit comprises a slip angle difference predicting section for predicting a difference between a slip angle of front wheels and a slip angle of rear wheels, and a correcting section for correcting, based on an angle difference signal outputted from the slip angle difference predicting section, a target torque signal supplied to the motor. Behavior of a vehicle is predicted from the angle difference signal and the target torque signal is corrected by a correction amount corresponding to the angle difference signal so that the motor can be drives controlled with the influence of a change in a road surface reaction force taken into consideration.

Abstract: An electric power steering apparatus includes a controller for controlling power assist of an electric motor so as to reduce a manual steering force required of the driver. The controller includes two closed control loops, one operating on the basis of a steering torque and the other on the basis of a differential value of the steering torque. The second closed control loop includes a differential torque compensator for compensating for the differentiated steering torque in such a manner as to increase the proportion of an assist torque developed in accordance with the change of the steering torque while keeping a desired degree of stability of operation of the steering system.

Abstract: An electric power steering apparatus transmits an auxiliary torque from an electric motor to a steering system via a mechanical clutch composed of a plurality of sets of friction clutch mechanisms. At least one of the plural clutch mechanism sets is disengageable in advance to the remaining clutch mechanism set. This means that only a part of the clutch mechanisms can be brought to the disengaged state at an advanced timing. When the selected part of the clutch mechanisms is disengaged, the remaining clutch mechanisms are subjected to an unbalanced force tending to disengage the remaining clutch mechanisms. By the effect of the unbalance force, frictional forces acting in the remaining clutch mechanisms are considerably reduced, so that the remaining clutch mechanisms can be disengaged by a small clutch-disengaging force. Thus, the mechanical clutch as a whole can be disengaged by a smaller manual effort or force than as required when all the clutch mechanisms are disengaged at one time.

Abstract: This invention is an electric power steering apparatus for applying the power of an electric motor to a steering system to reduce the steering torque, comprising a steering torque detection means, steering rotating speed detection means, a differential operation means, an electric motor control signal determination means, and an electric motor drive means.