Gas generation with reduced NOx formation

• US 6,673,173 B1
• Filed: 06/28/2000
• Issued: 01/06/2004
• Est. Priority Date: 02/02/2000
• Status: Expired due to Fees

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Taylor, Robert D., Mendenhall, Ivan V., Smith, Robert G., Parkinson, David W., Rink, Karl K.
• Primary Examiner(s): Carone, Michael J.
• Assistant Examiner(s): FELTON, AILEEN BAKER
• Application Number:
  US09/605,104
• Time in Patent Office: 1,287 Days
• Field of Search: 149/36, 149/45, 280/741, 602/19
• US Class Current: 149/45
• CPC Class Codes: B60R 21/264 using instantaneous generation of gas, e.g. pyrotechnic B60R21/268 takes precedence
• CPC Class Codes: C06D 5/04 by auto-decomposition of single substances

Abstract

Gas generating compositions containing or including a sufficient quantity of a non-nitrate containing ammonia source whereby, upon reaction of the gas generating composition, NO_x products are present in the product gas in a reduced amount as compared to reaction product gas resulting from reaction of the same composition without said quantity of non-nitrate containing ammonia source. Also disclosed are associated methods of reducing NO_x products present in an effluent of a gas generating composition that upon combustion forms gas useful for inflating a vehicle occupant safety restraint device.

Claims

1. A gas generating composition that upon combustion forms product gas useful for inflating a vehicle occupant safety restraint device, the gas generating composition comprising:

greater than 30 and less than 70 percent by weight of a guanidine nitrate fuel component;

greater than 30 and less than 70 percent by weight of a metal ammine nitrate oxidizer component;

greater than 1 and less than 10 percent by weight of a metal oxide burn rate enhancing and slag formation additive; and

greater than 1 and up to about 4 percent by weight of a non-nitrate containing ammonia source whereby, upon reaction of the gas generating composition, NO_x products are present in the product gas in a reduced amount as compared to reaction of the same composition without said quantity of non-nitrate containing ammonia source,

wherein the gas generating composition has a burn rate in excess of 0.45 inches per second at 1000 psi.

2. The gas generating composition of claim 1 wherein the non-nitrate containing ammonia source comprises an ammonium sulfate.

3. The gas generating composition of claim 1 wherein the non-nitrate containing ammonia source comprises an ammonium phosphate.

4. The gas generating composition of claim 1 wherein the composition has a combustion flame temperature of greater than about 1800 K.

5. The gas generating composition of claim 1 additionally comprising a scavenging agent effective to form a non-volatile combustion product which contains the anion of the non-nitrate containing ammonia source.

6. The gas generating composition of claim 5 wherein the scavenging agent comprises a metal compound of at least one metal selected from the group consisting of copper and zinc.