US 7,516,003 B2
Vehicle steering system
Naoki Maeda, Kashihara (Japan); Kosuke Yamanaka, Kashiwara (Japan); Masanori Arima, Nara (Japan); Atsushi Ishihara, Yamatokoriyama (Japan); Tatsuma Kouchi, Kashiwara (Japan); Shingo Maeda, Kashiwara (Japan); and Daisuke Maeda, Kashiwara (Japan)
Assigned to JTEKT Corporation, Osaka-shi (Japan)
Filed on Jun. 06, 2007, as Appl. No. 11/758,902.
Claims priority of application No. 2006-158549 (JP), filed on Jun. 07, 2006.
Prior Publication US 2007/0288142 A1, Dec. 13, 2007
Int. Cl. B62D 6/00 (2006.01); B62D 1/00 (2006.01); B62D 15/00 (2006.01)
U.S. Cl. 701—41  [701/42; 701/43; 180/204; 180/6.24] 4 Claims
OG exemplary drawing
 
1. A vehicle steering system comprising:
a steering mechanism including a steering part connected to at least one vehicle wheel to steer the vehicle, and a control member to be manipulated by the driver to control the steering part;
a steering actuator for imparting a steering force to the steering mechanism;
an automatic steering controller for performing an automatic steering control by controlling the steering actuator;
a driving state detector for detecting a driving state of the vehicle during the automatic steering control, wherein the detected driving state includes an angular velocity of the control member;
a torque detector that detects a manipulating torque applied to the control member;
torque threshold value setting means for variably setting a torque threshold value for permitting an intervention in the automatic steering control based on the detected driving state, wherein the torque threshold value setting means determines the torque threshold value so as to become smaller as the detected angular velocity of the control member becomes faster; and
automatic steering intervention means for intervening in the automatic steering control when the manipulating torque detected by the torque detector exceeds the torque threshold value set by the threshold value setting means,
whereby the automatic steering intervention means intervenes in the automatic steering control at a lower detected torque for faster detected angular velocities of the control member.