Hybrid airbag inflator

A hybrid airbag inflator comprises:

• a disk-shaped pressure vessel having a central axis with a domed upper housing portion with a sealed exhaust port for releasing inflation gases and a domed lower body portion welded to the domed upper housing portion, the domed lower body portion having one or more protrusions extending from an outer or exterior surface positioned offset from the center axis, at least one of the protrusions housing an igniter assembly with accessible electrical connections;
• and
• wherein the disk-shaped pressure vessel contains gas generant pellets and a quantity of pressurized inert gas for inflating an airbag;
• wherein the domed lower body portion has three of the protrusions equally spaced apart at 120 degrees around and offset from the axis, each of said three protrusions extending vertically from the outer or exterior surface by a vertical distance equal to the other protrusions forming a petaloid;
• wherein the domed upper housing portion has three protrusions equally spaced apart at 120 degrees around and offset from the axis, each of said three protrusions extending vertically from the outer or exterior surface by a vertical distance equal to the other protrusions forming a petaloid.