US Patent 10369956 Side airbag with necking chamber

A side airbag for a vehicle includes a main chamber and a necking chamber. The main chamber has an opening for connecting to an inflator and a first thickness in an inflated condition. The necking chamber is peripherally surrounded by the main chamber and is connected to the main chamber by a restrictive vent. The necking chamber has a second thickness in the inflated condition less than the first thickness and is aligned with a targeted body area.