Side airbag apparatus

A side airbag apparatus comprising:

• an airbag that includes an inflation portion that inflates by inflation gas supplied in response to an impact applied from a side to a vehicle seat, and that deploys toward a front of the vehicle seat at a side of the vehicle seat, wherein an opening is provided in a wall portion forming the inflation portion;
• and
• an outflow amount changing apparatus, wherein, when the inflated part of the inflation portion restrains an occupant, the outflow amount changing apparatus changes an amount of the inflation gas flowing out from the inflated part to an outflow amount that is different from an outflow amount in a case in which the inflation gas passes through only the opening,
• wherein
• the wall portion is configured by a dividing portion that is arranged in the inflation portion and divides at least a part of the inflation portion into an upstream inflation portion, to which the inflation gas is supplied, and a downstream inflation portion, which is adjacent to the upstream inflation portion and to which the inflation gas is supplied via the opening,
• the opening is configured by a slit that is provided in the dividing portion and extends in a widthwise direction of the vehicle seat when the dividing portion comes to be in a tensed state,
• the outflow amount changing apparatus is configured by an auxiliary opening,
• the auxiliary opening is configured by a slit provided in a section of the dividing portion that is different from the opening, and extends in the widthwise direction of the vehicle seat when the dividing portion comes to be in the tensed state,
• a dimension of the dividing portion in a vertical direction is set larger than a dimension of the dividing portion in a lateral direction,
• at least one of the opening and the auxiliary opening is provided as a specific opening at a section in the vertical direction where an external force applied due to the occupant restraint by the upstream inflation portion is the largest, and
• the opening and the auxiliary opening with the dividing portion in the tensed state are more forcefully pulled in the lateral direction than in the vertical direction, and thereby close.