Abstract: Gas generated from an inflator flows into a first portion of a main bag and each part of an inner bag, and the first portion is inflated toward an area in front of passenger's seat. Then, the gas filling the first portion which has been inflated flows into a second portion of the main bag. In this situation, the inflation direction of the second portion is more downward than the inflation direction of the first portion. As a result, a speed of backward inflation is decreased.

Abstract: An air bag device mounted in an instrument panel has an inflator for supplying gas, a bag body having a gas inlet hole, and an inner bag disposed inside of the bag body. The inner bag is formed with a pair of first through-holes and a second through-hole so that an opening area of the first through-hole is larger than that of the second through-hole. The inner bag is expanded by the gas supplied from the inflator, while a large amount of the gas is discharged from the first through-hole. Accordingly, the air bag body is expanded toward the waist of a passenger on a passenger seat. At the same time, the gas is discharged from the second through-hole to flow along an inside of a windshield, whereby the air bag can be also expanded toward the head of the passenger. As a result, even if the inflator is mounted in the instrument panel at its upper portion, the air bag device can securely protect the passenger on the passenger seat.