Patent ID: 8567817

Claim:
A side airbag device for a vehicle comprising: a side airbag that includes a high-pressure chamber, which has a high pressure at a time of inflation and expansion, and a low-pressure chamber, which has a lower pressure than the high-pressure chamber, the high-pressure chamber and the low-pressure chamber each inflating and expanding at a time of side collision; a partition wall that is disposed in the side airbag and partitions the high-pressure chamber from the low-pressure chamber; an inflator that is disposed in the low-pressure chamber in a state in which a gas discharge section faces the high-pressure chamber and is disposed at the low-pressure chamber side relative to the partition wall, that supplies gas for inflation mainly toward the high-pressure chamber and that also supplies the gas for inflation to the low-pressure chamber; and a check valve that is disposed at the partition wall, that permits the gas discharged from the gas discharge section of the inflator to flow from the low-pressure chamber to the high-pressure chamber, and that restricts a flow of the gas in the opposite direction; wherein: in the side airbag in an inflated and expanded state: the inflator is disposed in the side airbag at a rear side with respect to a vehicle seat in a front-to-rear direction of the vehicle, the partition wall is disposed at a position that corresponds with an abdomen area of an occupant sitting on the vehicle seat, the high-pressure chamber is a lower chamber that corresponds with a waist area of the occupant, and the low-pressure chamber is an upper chamber that corresponds with at least one of a chest area or a shoulder area of the occupant, and the partition wall is formed by sewing together, of an upper fabric that constitutes the upper chamber, a lower edge of an outer side fabric that is disposed at an outer side with respect to the vehicle seat in a seat-width direction and a lower edge of an inner side fabric that is disposed at an inner side in a seat-width direction, and the check valve is disposed at a rear side in the side airbag in a front-to-rear direction of the vehicle, and is formed by extending the upper fabric to a seat downward side.