Patent ID: 7905313

Claim:
A vehicle seat-belt apparatus comprising: a forward monitoring device which conducts monitoring to the front of a vehicle; an avoidance assist device which supports a predetermined avoidance operation in order to avoid an obstacle when it is determined that there is an obstacle to be avoided based on a detection result of the forward monitoring device, the avoidance assist device including a linear braking device which imparts a predetermined braking force to the vehicle when the forward monitoring device detects the obstacle, and a turning-force support device which imparts a turning force to the vehicle; a motor which conducts a rotary driving of a belt reel on which a belt is wound; a control device which controls the motor; a road-surface friction coefficient estimation device which estimates a friction coefficient of a road surface during the operation of the linear braking device; a first control map of a vehicle speed in direct relation to the friction coefficient; and a second control map of the vehicle speed in direct relation to the friction coefficient, wherein the control device conducts a drive control of the motor by a first control mode during an operation of the linear braking device, and conducts the drive control of the motor by a second control mode that differs from the first control mode during an operation of the turning-force support device, during the first control mode, the control device selects the first control map when the friction coefficient is larger than a predetermined threshold value friction coefficient, and selects the second control map when the friction coefficient is smaller than the predetermined threshold value friction coefficient, the control device increases or decreases a winding position of the belt reel or a current volume impressed on the motor based on the friction coefficient of the road-surface when the drive control is conducted by the second control mode, and the road-surface friction coefficient estimation device includes a brake controller that is constituted to perform a road-surface friction coefficient estimation braking, during the first control mode when the road-surface friction coefficient estimation is performed, the road-surface estimation braking is performed.