AIR BAG DEVICE FOR VEHICLE

摘要

PROBLEM TO BE SOLVED: To allow gas pressure to be sufficiently released upon primary collision while coping with the secondary collision without adding up to the cost. SOLUTION: An air bag case 11 fixed to the vehicle body houses a fixed inflator 12 and a folded air bag 13. The inside and outside of the air bag case 11 is communicated through a connecting portion 14 constituting a vent hole. An opening/closing valve 15 for adjusting the effective opening area of the connecting portion 14 is controlled for opening/closing by an actuator 16. The actuator 16 is controlled by a control unit U. The opening/closing valve 15 is normally opened in front such that the inflator 12 explodes to inflate the air bag 13 upon front collision. When a pressure sensor 17 detects that the pressure within the air bag case 11 decreases to a predetermined pressure after inflation of the air bag 13, the opening/closing valve 15 is fully opened. After the elapse of a predetermined time when the air bag 13 starts inflating, the opening/closing valve 15 may be fully closed.