Patent ID: 7971678
Filing Date: 2011-07-05
Classification: B62D

Abstract:
1. A vehicle steering device, comprising: a steering wheel operable by a driver and having a steering wheel shaft connected thereto; a turning mechanism operable to turn at least one steered wheel; a turning actuator operable to apply torque to the turning mechanism; a reaction force actuator connected to the steering wheel to apply a steering reaction force thereto; a selectively engageable clutch positioned between the steering wheel and the turning mechanism and including a first rotary member mechanically connected to the turning mechanism, a second rotary member mechanically connected to the steering wheel shaft, and an engaging piece interposed between the first rotary member and the second rotary member, the clutch having an engaged position when the engaging piece is in wedging engagement between the first rotary member and the second rotary member wherein the steering wheel shaft is mechanically connected to the turning mechanism for turning the at least one steered wheel, and the clutch having a disengaged position when the engaging piece is in intermediate position between the first rotary member and the second rotary member wherein the steering wheel shaft is mechanically separated from the turning mechanism for steer-by-wire control of the at least one steered wheel; and a steering control part configured to control the turning actuator according to a steering angle of the steering wheel when the clutch is in the disengaged position such that a turning angle of the at least one steered wheel corresponds to the steering angle of the steering wheel and to simultaneously control the reaction force actuator to apply a steering reaction force to the steering wheel, the steering control part further configured to prevent the clutch from moving to the engaged position in response to a detection of an operating condition by controlling at least one of the turning actuator and the reaction force actuator to reduce a relative angular acceleration between the steering wheel and the turning mechanism.