US Patent 7887090 Ignition delay module for an airbag inflator

An ignition delay module (10) for use in an airbag inflator (100, 200) has an ignition delay module housing (11). The ignition delay module (10) separates the inflator (100, 200) into two chambers (40, 60). A pyrotechnic tablet (2) is positioned inside the ignition delay module housing (11). Upon activation of the inflator (100, 200) the ignition delay module (10) prevents a gas generant (62) in a second chamber (60) of the inflator (100, 200) from igniting until at least a portion of the pyrotechnic tablet (2) is burnt. Preferably a burn inhibitor layer (3) is affixed or otherwise applied to a surface of the pyrotechnic tablet (2). The ignition delay module housing (11) has a first end with a plurality of openings (7) and a second end with openings (20) blocked by the pyrotechnic tablet (2) at the burn inhibitor layer (3) such that upon an ignition of a gas generant (42) in the first inflator chamber (40), the burn inhibitor layer (3) is overcome and the pyrotechnic tablet (2) is ignited and burns to expose the openings (20) in the second end of the ignition delay module housing (11) causing a time delay before igniting a gas generant (62) in the second chamber (60). The ignition delay module (10) is usable in either a pyrotechnic inflator (100) or a hybrid inflator (200).