SIDE AIRBAG DEVICE FOR VEHICLE

An airbag cushion of a side airbag device has a pre-push chamber that initially receives gas from an inflator, and a main chamber that receives gas from the pre-push chamber. The pre-push chamber has a pre-upper chamber aligned with a seat back and a pre-lower chamber aligned with a seat cushion. A main chamber has a main upper chamber connected to the pre-upper chamber via a first inner vent, a main lower chamber connected to the pre-lower chamber via a check valve, and a baffle demarcating the upper main chamber and the lower main chamber.