Variable output driver side hybrid inflator

An inflator device (20) for use in inflating an air bag or air cushion comprising:

• a pressure vessel (22) defining an enclosed volume (44) containing stored inflation gas, said pressure vessel comprising a toroidal pressure vessel portion (23) having circular inner wall and outer wall portions, the inner wall portions defining an annular space (25), and reinforcing means (60, 62, 60') secured to at least an exterior of the inner wall portion about the annular space for reinforcing the pressure vessel in relation to internal pressure forces;
• pyrotechnic means (200a,b or 310) in said toroidal pressure vessel portion for heating said stored inflation gas within the pressure vessel to a pressure level to open a rupturable disk to permit said stored inflation gas to exit the inflator device.