Jtekt Corporation

Koyo Seiko Company, Ltd.

Yasuhiro Kamatani

Toshiaki Oya

Kazuhiro Watanabe

Shigeki Nagase

Takeshi Ueda

Katsutoshi Nishizaki

Masahiko Sakamaki

Osamu Sano

Akihiko Shiina

Shirou Nakano

Ken Matsubara

Takehiro Saruwatari

Yoshikazu Kuroumaru

Yasuhiro Saitou

Takayasu Yamazaki

Yoshimi Kotake

Takashi Ohata

Ryouichi Tokioka

Hiroji Ueda

Katsuyuki Oguchi

Masayoshi Ashitaka

Takeshi c/o Jtekt Corporation Ueda

Yasuhiro c/o Jtekt Corporation Saitou

In a control method for an electric power steering apparatus having a steering member, a steering mechanism, and a motor for assisting steering, a steering torque applied to a steering wheel is detected, frequency analysis is performed on the detected torque, and a determination is made as to whether or not a torque component having a frequency equal to or higher than a predetermined value is included in the result of the frequency analysis. When such a torque component is included in the frequency analysis result, a predetermined rotary torque is generated in a single direction.

Electric power steering apparatus and method for controlling same

An electric power steering system is provided which is capable of providing a favorable steering feeling without using compensation logics such as of inertia compensation and friction compensation. The electric power steering system includes road-noise suppression control means () for controlling a steering assist motor () in a manner to damp torque transmission in a higher frequency region representing road noises than a frequency region representing road information. A friction value of a steering mechanism (A) is decreased enough to allow the intrinsic vibrations of the steering mechanism (A) to appear. Rotor inertia of the steering assist motor () is set to a value small enough to allow the frequencies of the intrinsic vibrations to be present in the frequency region where the torque transmission is damped by the road-noise suppression control means ().

Electric power steering system

In a hydraulic power steering apparatus, when the relative rotation between input and output shafts which are connected by a torsion bar is converted into the relative rotation between an outer valve element and an inner valve element, the ratio of the relative rotation angle of the latter to the relative rotation angle of the former is varied in accordance with an operating condition of a vehicle. The hydraulic pressure to generate steering assist force is controlled in accordance with the relative rotation angles between both valve elements. The outer valve element is capable of relative coaxial rotation to the input and output shafts, and the inner valve element is formed integrally with the input shaft. A swinging member is supported by first, second and third supporting parts which respectively rotate together with the input shaft, the output shaft or the outer valve element. One of the first, second and third supporting parts is displaced in the axial direction by a certain distance in accordance with the operating condition of the vehicle.

Hydraulic power steering apparatus

Growing community of inventors

Kitakatsuragi-gun, Japan

Yasuhiro Kamatani