Side airbag apparatus

A side airbag apparatus applied to a vehicle, the vehicle being structured such that a seat back of a vehicular seat is provided with a seat frame and a seat pad arranged near the seat frame, wherein a rear frame portion of the seat frame is arranged near a rear end in an intermediate portion in a vehicle width direction of the seat back, and an intermediate pad portion of the seat pad is arranged near a front end in the intermediate portion, the side airbag apparatus comprising:

• an inflator;
• and
• an airbag inflated by a gas jetted out of the inflator,
• wherein the inflator and the airbag are incorporated at least on an outer side portion of the seat back,
• wherein the airbag has a main airbag and an auxiliary airbag,
• wherein the main airbag is inflated between a body side portion of the vehicle and an occupant seated on the vehicular seat by being caused to shoot out forward from an outer side portion of the seat back by a gas from the inflator, and
• wherein the auxiliary airbag pressing a portion near the outer side portion of the intermediate pad portion forward by being inflated between the rear frame portion and the intermediate pad portion by the gas from the inflator.