Airbag apparatus , installed on a vehicle seatbelt

The present invention is intended to provide an airbag apparatus for vehicles, which is provided to protect a vehicle occupant by instantaneously inflating an airbag at the time of an accident such as a collision of a vehicle or automobile, and is capable of securely holding and protecting the occupant and reducing injury to the occupant. The airbag apparatus (1) of the invention comprises an airbag (30) which is inflated by being filled with gas, airbag inflating means (31) for jetting gas and filling the airbag (30) with the gas, and an acceleration sensor (43, 44) for detecting acceleration, the airbag apparatus being installed on the seat belt worn by the occupant. Since the direction of the gas jetted by the airbag inflating means (31) is nearly parallel to an imaginary plane (56) including a surface of a seat belt (17), when the airbag (30) is inflated, the airbag apparatus (1) does not strongly press the occupant (42), and yet securely holds the occupant (42), whereby injury to the occupant can be minimized.