Gas generant

Abstract

The present invention includes a gas generator 10 that incorporates a gas generating composition 12 and a scavenging additive 16 in heterogeneous but vapor/gaseous communication with the gas generating composition 12 . The scavenging additive retains moisture/contaminants typically evolving over time at relatively higher temperatures. The present invention further includes a gas generating system 180 incorporating the gas generator 10.

1 . A gas generator comprising:
 a gas generating composition comprising a first oxidizer and a first fuel; and   a scavenging additive selected from adsorbents, absorbents, chemical reactants, and mixtures thereof, said scavenging additive provided in vapor/gaseous communication with said gas generant composition within said gas generator, in heterogeneous relationship with said gas generant composition.   
     
     
         2 . The gas generator of  claim 1  wherein said first oxidizer is selected from metal and nonmetal nitrates; metal nitrites, metal and nonmetal perchlorates, metal oxides, basic metal nitrates, said first oxidizer provided at about 0.1 to 80% by weight of the gas generant composition. 
     
     
         3 . The gas generator of  claim 1  wherein said first fuel is selected from derivatives of bis-(1(2) H-tetrazol-5-yl)-amine including its anhydrous acid, its acid monohydrate, mono-ammonium salt of bis-(1(2) H-tetrazol-5-yl)amine, metal salts, and complexes thereof; azoles, metal salts of azoles, nonmetal and metal salts of nitramine derivatives of azoles; guanidines; salts of guanidines; nitro derivatives of guanidines; azoamides; nitrate salts of azoamides, and mixtures thereof; said second fuel provided at about 0.1-50% by weight of the gas generant composition. 
     
     
         4 . The gas generator of  claim 1  wherein said adsorbents, absorbents, chemical reactants, and mixtures thereof are selected from the group including molecular sieves, zeolites, calcium oxide, and calcium sulfate. 
     
     
         5 . The gas generator of  claim 1  wherein said gas generating composition further comprises a second additive selected from silicon, silicon dioxide, fused silicon, silicones; silicates; natural minerals including clay, mica, and silica; lubricants including graphite, magnesium stearate, boron nitride, molybdenum sulfide, and mixtures thereof, said second additive provided at about 0.1 to 10% by weight of the gas generant composition. 
     
     
         6 . The gas generator of  claim 1  wherein said scavenging additive is provided at about 0.05 to 10% by weight of the gas generant composition. 
     
     
         7 . The gas generator of  claim 1  wherein said gas generating composition further comprises a binder selected from cellulose derivatives, polyalkenes carbonates, and mixtures thereof, said binder provides at about 0.1 to 10% by weight of the gas generant composition. 
     
     
         8 . A gas generating system comprising the gas generator of  claim 1 . 
     
     
         9 . A vehicle occupant protection system comprising the gas generator of  claim 1 . 
     
     
         10 . The gas generator of  claim 1  wherein said gas generating composition comprises the mono-ammonium salt of bis (1(2) H-tetrazol-5-yl)-amine at about 0.1 to 50% by weight of the gas generant composition, phase stabilized ammonium nitrate at about 0.1 to 80% by weight of the gas generant composition, and, molecular sieves provided at about 0.1 to 10% by weight of the gas generant composition. 
     
     
         11 . The gas generator of  claim 1  wherein said first oxidizers are selected from ammonium nitrate, phase stabilized ammonium nitrate, potassium nitrate, strontium nitrate, potassium nitrite, potassium chlorate, potassium perchlorate, ammonium perchlorate, iron oxide, copper oxide, basic copper, nitrate, basic iron nitrate and mixture thereof. 
     
     
         12 . The gas generator of  claim 1  wherein said first fuel is selected from a potassium, sodium, strontium, copper, boron and zinc salt of bis-(1(2)H-tetrazol-5-yl)-amine; 5-aminotetrazole; potassium 5-aminotetrazole; mono-ammonium salt of 5,5-bis-1H-tetrazole and di-ammonium salt of 5,5-bis-1H-tetrazole; 5-aminotetrazole nitrate; nitraminotetrazole; dipotassium 5-nitraminotetrazole; mono-ammonium nitraminotetrazole and di-ammonium nitraminotetrazole; dicyandiamide; guanidine nitrate; nitroguanidine; azodicarbonamide, azodicarbonamidine di-nitrate; and mixtures thereof. 
     
     
         13 . A gas generator comprising:
 a gas generating composition comprising a first oxidizer and a first fuel; and   a scavenging additive selected from adsorbents, absorbents, chemical reactants, and mixtures thereof, said scavenging additive provided in vapor/gaseous communication with said gas generant composition within said gas generator, in separate but proximate relationship to said gas generant composition.   
     
     
         14 . A gas generator comprising:
 a gas generating composition comprising a first oxidizer and a first fuel, said gas generant composition provided in pressed form; and
 a scavenging additive selected from adsorbents, absorbents, chemical reactants, and mixtures thereof, said scavenging additive provided in vapor/gaseous communication with said gas generant composition within said gas generator, and sprinkled about said gas generant composition in heterogeneous relationship thereto.