Seatbelt device

A seatbelt device for a reclining seat of a vehicle, the seatbelt device comprising:

• a seatbelt retractor attached to a seat back of the reclining seat and configured to wind up a seatbelt when necessary;
• and
• a cable advancing/retracting mechanism disposed at a coupling portion at which the seat back and a seat cushion of the reclining seat are coupled to each other and configured to detect an inclination angle of the seat back when the seat back is tilted in a front-back direction of the vehicle, the cable advancing/retracting mechanism including a cable configured to transmit the inclination angle to the seatbelt retractor and advance and retract in a longitudinal direction of the cable over a distance corresponding to the inclination angle of the seat back,
• the seatbelt retractor including:
• a retractor frame fixed to the seat back as inclined in a left-right direction of the vehicle with respect to a line extending in an up-down direction at a center of the seat back in the left-right direction;
• a spindle supported by the retractor frame and configured to wind up the seatbelt;
• an acceleration sensor attached to the refractor frame to detect acceleration in the front-back direction of the vehicle;
• a lock mechanism configured to lock draw-out operation for the seatbelt in accordance with the acceleration in the front-back direction of the vehicle detected by the acceleration sensor;
• and
• an attitude control mechanism configured to keep a sensor reference surface of the acceleration sensor horizontal,
• the acceleration sensor including:
• a sensor cover fixed to the retractor frame;
• an inertial element configured to be moved in the front-back direction of the vehicle when acceleration that is equal to or more than a predetermined value is applied in the front-back direction of the vehicle;
• a sensor housing supported on the sensor cover and having a swing axis extending along the left-right direction of the vehicle and an inertial element support surface on which the inertial element is placed;
• and
• an actuation member configured to actuate the lock mechanism to lock the draw-out operation in conjunction with movement of the inertial element in the front-back direction of the vehicle, and
• the attitude control mechanism including:
• a rotary member configured to be turned by an angle corresponding to a distance over which the cable is advanced or retracted by the cable advancing/retracting mechanism;
• and
• a rotation transfer mechanism configured to transfer rotation of the rotary member to the sensor housing to swing the sensor housing in the front-back direction of the vehicle, wherein
• a turning axis of the rotary member and the swing axis of the sensor housing intersect each other at a predetermined angle with respect to the left-right direction of the vehicle with the swing axis of the sensor housing arranged in a horizontal direction with respect to the left-right direction of the vehicle, and
• the inertial element support surface of the sensor housing is kept horizontal by swing motion of the sensor housing in the front-back direction of the vehicle even if the seat back is tilted in the front-back direction of the vehicle.