Abstract: A compact filtering device for use in pyrotechnic gas generators comprising of series of small conduits which generally transport the exhaust products from the combustor exit ports to the generator exit ports. Particulate traps (12): which are created by locating the conduit exit ports (11) at some point prior to the conduit end. Particulate traps (12) consisting of entire conduits are created by placing one end (10) of the conduits at a point where the gas stream is forced to make a 90.degree. change in direction and by orienting the longitudinal axis in the direction of the original flow path. Because the traps are then located outside the flow path the particulate, once deposited, will remain in the trap. The device is capable of capturing all of the particulate generated without any change in resistance to gas flow.

Abstract: A process for preparing a porous propellant grain which comprises blending at least two combustible materials to form a homogeneous mixture, adding a predetermined amount of a liquid dispersant to said mixture to form a slurry, and flash drying the slurry in order to form a porous, single grain propellant having a greatly increased burning surface. A single grain propellant is produced having a flat, torroidal shape with a central cylindrical core and honeycombed with a plurality of porous channels extending entirely through the grain to increase the burning surface thereof.

Abstract: A gas generating composition is disclosed for generating nitrogen gas free from noxious and toxic impurities consisting of an alkali metal azide, at least a stoichiometric amount of a metal oxide or a mixture of metal oxides and an ammonium perchlorate burn rate enhancer. The nitrogen gas can be used to inflate an impact protection air cushion of an automotive restraint system.

Abstract: A method and apparatus are disclosed for pyrotechnically generating a mixture of at least two gases, substantially in a predetermined ratio, for an extended period of time, with separate pyrotechnic charges generating each component of the resultant mixture. At least one of the pyrotechnic charges is capable of sustained burning at a rate corresponding to the rate of total gas generation, and the remaining charges, not in themselves capable of sustained burning, are caused to sustain ignition by maintaining their burning surface in thermal communication with that of the first charge, so that all charges burn at substantially the same linear rate.

Abstract: A gas generating composition is disclosed wherein the combustible reactants are an alkali metal azide and a metal oxide which upon thermal initiation react to produce alkali metal oxide, metal and pure nitrogen gas which can be used to inflate an impact protection air cushion of an automotive restraint system.