Abstract: An inflatable restraint system includes an airbag which is expanded by an inflator assembly to restrain movement of an occupant of a vehicle in the event of a collision. The inflator assembly includes a plurality of grains or bodies of gas generating material which are disposed in a longitudinally extending array and are enclosed by a filter assembly and a housing. To promote a rapid and uniform combustion of the grains to quickly generate a large volume of gas, passages extend through the grains between spaces at opposite ends of the grains. Uniform combustion of the grains is promoted by having the passages located on concentric circles with the longitudinal axes of the passages spaced apart by equal distances along the circles. The axes of the passages on one concentric circle are circumferentially spaced from the axes of the passages on another concentric circle. The grains positioned with the passages in axial alignment and are cushioned by resilient retainer tubes which engage the outside of the grains.

Abstract: A structure and assembly technique for providing an internal reinforcement for an air bag module to restrain bulging of the module while minimizing the size of the module. The air bag module comprises a container with a wall defining a cavity for a gas generator and at least a part of an air bag. The wall also defines an opening through which at least part of the bag is inserted into the cavity. A reaction member, preferably a fabric tether strap, is connected with at least two points of the wall adjacent the container opening and extends across the opening in the container. The tether strap is located internally of the container and resists deformation of the container under the pressures of air bag deployment, without increasing the size of the module. The tether strap is preferably constructed as a part of the air bag itself, and is incorporated into the container at the time the air bag is assembled with the container.

Abstract: An inflatable restraint system includes an airbag which is expanded by an inflator assembly to restrain movement of an occupant of a vehicle in the event of a collision. The inflator assembly includes a plurality of grains or bodies of gas generating material which are disposed in a longitudinally extending array and are enclosed by a filter assembly and a housing. To promote a rapid and uniform combustion of the grains to quickly generate a large volume of gas, passages extend through the grains between spaces at opposite ends of the grains. Uniform combustion of the grains is promoted by having the passages located on concentric circles with the longitudinal axes of the passages spaced apart by equal distances along the circles. The axes of the passages on one concentric circle are circumferentially spaced from the axes of the passages on another concentric circle. The grains positioned with the passages in axial alignment and are cushioned by resilient retainer tubes which engage the outside of the grains.

Abstract: Structure for generating nitrogen gas for inflating an air bag vehicle occupant resistant comprises a grain made of an azide based material which generates gas upon combustion. The grain has an ignition enhancing coating thereon consisting essentially of 30 to 50% by weight of an alkali metal azide, 40 to 60% by weight of sodium nitrate or potassium perchlorate, 5 to 15% by weight of boron, and 1 to 15% by weight of sodium silicate. The coating may also include 1 to 6% by weight of graphite fibers as a roughening agent.

Abstract: Structure for generating nitrogen gas for inflating an air bag vehicle occupant restraint comprises a grain made of an azide based material which generates gas upon combustion. The grain has an ignition enhancing coating thereon consisting essentially of 20 to 50% by weight of an alkali metal azide, 25 to 35% by weight of an inorganic oxidizer, 10 to 15% by weight of a fluoroelastomer binder, 15 to 25% by weight of magnesium, and 1 to 3% by weight of fumed silicon dioxide. The coating may also include 1 to 6% by weight of graphite as a roughening agent.

Abstract: In an inflatable occupant-restraint system in a vehicle, a generator for producing fluid under pressure is so placed that a portion of the generator is outside the cushion and has a resilient venting means for dumping increasing fractions of gas volume outside the cushion at increasing operating temperatures.

Abstract: A filter assembly is provided for fluid supplies for vehicle occupant restraint systems which employ a combustible gas generator to inflate a confinement upon the occurrence of a collision. The filter assembly includes two sets of layers of porous filter material.One set includes a plurality of layers of fibrous filter material of relatively high porosity such as steel wool. The other set includes a plurality of layers of filter material arranged in order of descending porosity between the gas generator and the confinement and positioned intermediate the layers of the former set. Each of the layers of this other set is of substantially lower porosity than those adjacent layers of the former set.

Abstract: A device for generating pressurized fluid for inflating inflatables such as for a vehicle occupant restraint. The present generator is of the combustible chemical type having a tubular housing with radial flow discharge port means. Combustible chemical gas generating material is disposed within the housing and annularly about a central thin wall tubular casing. Longitudinally fast-burning booster charge means is disposed within the central casing and is ignited at one end of the casing. Upon ignition, the booster charge burns progressively along the length of the tubular casing causing progressive longitudinal rupture for nearly instantaneous ignition of the portions of the gas generating material adjacent the casing. The resultant substantially instantaneous ignition of the gas generating material along the full length thereof produces uniform radial burning of the gas generating material.

Abstract: A relatively low temperature nitrogen gas generating composition is disclosed which consists essentially of (a) from about 10 to about 50 percent by weight of an oxidizer selected from the oxides of iron, nickel and cobalt, said oxidizer having a primary particle size in the range from about 0.1 micron to about 7 microns in diameter; and, (b) at least 50 percent by weight of an alkali metal azide. Optionally, less than about 10 percent by weight of an alkali metal perchlorate may be included as a booster. The nitrogen gas generating composition provides the nitrogen gas at a low enough temperature but at a sufficiently high speed, without generating a large quantity of finely divided solid residue particles. A major portion of the combustion residue is a coherent porous solid sinter or fused mass of residue particles which autogenously provides both self-filtration of ejected particles and sorption of any molten combustion product.

Abstract: A fluid supply is provided for inflating a vehicle occupant restraint system of the type activated in response to a vehicle collision signal. The fluid supply includes a housing defining a fluid discharge port, combustible gas generating means disposed within the housing and means operable to activate the gas generating means to produce gaseous combustion products. A filter pack is disposed between the gas generating means and a discharge port means and includes a plurality of layers of filter material, such as fiberglass or steel wool, with each of the layers being at least as porous as the next adjacent downstream layer to cause filtration of progressively finer particles as the gaseous combustion products move downstream. This progressive filtering minimizes clogging of the filter pack.

Abstract: A filter assembly is provided for a cylindrical radial flow fluid supply having a combustible gas generator which is used to inflate a confinement for an occupant restraint system upon the occurrencee of a collision. The filter assembly includes a plurality of layers of filter material and support elements pressed to a densely packed flat form, rolled, closed, and inserted in the housing of the fluid supply adjacent the combustible gas generator.

Abstract: An inflator is provided for inflating the expandable confinement of a vehicle occupant restraint system, to restrain an occupant in response to a collision signal. The inflator contains a source of inflation fluid, such as a propellant which is ignited upon the receipt of the collision signal. The inflator has fluid-directing means including passage means for the flow of the inflating fluid therethrough. A deformable diffuser is provided having a first position in sealing engagement with the outer surface of the inflator to seal the passage means, and a second position, subsequent to the ignition of the propellant, in which a portion of the diffuser is deformed out of sealing engagement with the inflator to permit passage of the inflating fluid. The fluid is directed by the diffuser radially away from the housing to inflate the confinement.

Abstract: An inflator for a vehicle occupant restraint system of the type having an inflatable confinement for restraining the vehicle occupant in the event of a collision. The inflator includes reservoir means containing pressurized fluid and gas generating means disposed within a region encompassed by the reservoir means, and means defining an outlet passage. The fluid outlet of the inflator is covered by a diffuser having a plurality of spaced peripheral exit ports, the diffuser having an initially collapsed closed condition and, upon activation of the gas generating means in response to a collision, the diffuser is moved to a deformed open position permitting fluid flow to the diffuser exit ports.