Kyb Corporation

Fuji Heavy Industries Ltd.

Yuichiro Okamoto

Hiroyuki Gotou

Kazuma Yamazaki

Nobuyuki Kimura

Takayuki Nagase

Kazuhiro Sasaki

Noboru Yoshida

Hisazumi Ishikawa

Kenji Nishikubo

Kouichi Yamashina

An electric power steering device includes a phase advance correction unit configured to advance a phase of a steering torque signal detected by a torque sensor detecting a steering torque input from a steering wheel, a specific frequency extraction unit configured to extract a component in a specific frequency band out of the steering torque signal detected by the torque sensor, a gain multiplication unit configured to correct a steering torque signal computed on the basis of an output signal of the phase advance correction unit and an output signal of the specific frequency extraction unit such that the steering torque signal reaches a limit value set by a limiter by multiplying the steering torque signal by a gain, and an addition unit configured to add an assist correction command value calculated on the basis of an output signal output from the gain multiplication unit to the assist command value.

Electric power steering device

An electric power steering device includes a basic return command value calculation unit configured to calculate a basic return command value in a direction to return a steering wheel to a neutral position on the basis of a steering angle of a steering wheel, a turn/return determination unit configured to determine the turn and the return of the steering wheel, a gradually changing return command value calculation unit configured to calculate a gradually changing return command value, the gradually changing return command value gradually increasing, while the return of the steering wheel is determined by the turn/return determination unit, and a return command value calculation unit configured to calculate a return command value by adding the gradually changing return command value to the basic return command value. The electric motor is driven by adding the return command value to the assist command value.

A electric power steering device includes a basic return command value calculation unit configured to calculate a basic return command value in a direction to return a steering wheel to a neutral position on the basis of a steering angle of the steering wheel, a return command value calculation unit configured to calculate a return command value by correcting the basic return command value by the first correction gain, and an opposite return command value calculation unit configured to calculate an opposite return command value in a direction not to return the steering wheel to the neutral position on the basis of an angular acceleration of an electric motor. A correction return command value is calculated on the basis of the return command value and the opposite return command value and the electric motor is driven by adding the correction return command value to the assist command value.

An electric power steering device includes a basic return command value calculation unit configured to calculate a basic return command value in a direction returning the steering wheel to a neutral position, on the basis of detection results of a steering angle detector detecting a steering angle of the steering wheel, a first correction gain calculation unit configured to calculate a first correction gain correcting the basic return command value, on the basis of detection results of a vehicle speed detector detecting vehicle speed, and a second correction gain calculation unit configured to calculate a second correction gain correcting the basic return command value, on the basis of a change amount of the steering torque detected by the torque sensor. The basic return command value is corrected by the first and second correction gains so as to calculate a return command value. The return command value is added to the assist command value so as to drive the electric motor.

Growing community of inventors

Hessen, Germany

Yuichiro Okamoto