Flares having igniters formed from extrudable igniter compositions

• US 6,170,399 B1
• Filed: 07/21/1998
• Issued: 01/09/2001
• Est. Priority Date: 08/30/1997
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Innovation Systems, Inc. (Northrop Grumman Corporation)
• Original Assignee: Cordant Technologies, Inc. (Howmet Aerospace, Inc.)
• Inventors: Lund, Gary K., Nielson, Daniel B., Blau, Reed J.
• Primary Examiner(s): Nelson, Peter A.
• Application Number:
  US09/119,518
• Time in Patent Office: 903 Days
• Field of Search: 102/275.4, 102/275.8, 102/336, 149/45
• US Class Current: 102/336
• CPC Class Codes: C06B 21/0075 by extrusion
• CPC Class Codes: C06C 15/00 Pyrophoric compositions; Flints chemical lighters C06C9/00; alloys in general C22C
• CPC Class Codes: C06C 9/00 Chemical contact igniters; Chemical lighters

Abstract

The present invention relates to flares and other solid propellant devices, rockets or the like, equipped with an igniter or igniter system which is based in whole in part on an extruded igniter stick.

Claims

1. A flare comprising a case, propellant contained within said case, and an igniter system comprising an extruded dry igniter element for igniting said propellant of said flare, said extruded dry igniter element deflagrating upon ignition and being formed from an extrudable igniter composition comprising, as ingredients prior to drying to form said dry igniter element, at least one water-soluble binder dissolved into an aqueous solution, at least one oxidizing agent, at least one fuel, and, optionally, fibers,

wherein said water-soluble binder comprises at least one member selected from the group consisting of a water-soluble polymeric binder, a water-soluble gum present in an amount of from about 2% by weight to about 10% by weight based on the total amount of dry ingredient in said extrudable igniter composition, and water-soluble gelatin, and

wherein formation of said extruded dry igniter element comprises drying the extrudable igniter composition of water.

2. The flare of claim 1, wherein said water-soluble binder comprises at least one member selected from the group consisting of poly-N-vinyl pyrolidone, polyvinylalcohol, copolymers of poly-N-vinyl pyrolidone and polyvinylalcohol, polyacrylamide, sodium polyacrylates, and copolymers of polyacrylamide and polyacrylates.

3. The flare of claim 2, wherein said water-soluble binder comprises poly-N-vinyl pyrolidone.

4. The flare of claim 2, wherein said water-soluble binder comprises polyvinylalcohol.

5. The flare of claim 2, wherein said water-soluble binder comprises gum.

6. The flare of claim 2, wherein said water-soluble binder comprises polyacrylamide.

7. The flare of claim 1, wherein said oxidizer is present in an amount of from about 40% by weight to about 90% by weight relative to the dry ingredients used in formulating said extrudable igniter composition.

8. The flare of claim 1, wherein said oxidizer comprises an organic oxidizer.

9. The flare of claim 1, wherein said oxidizer comprises at least one ionic species selected from the group consisting of nitrate, nitrite, chlorate, perchlorate, peroxides, and superperoxides.

10. The flare of claim 1, wherein said extrudable igniter composition contains fibers.

11. The flare of claim 10, wherein said fibers comprise at least one of polyolefin fibers, polyamide fibers, polyester fibers, or poly(2,2′

-(m-phenylene)-5,5-bisbenzimidazole fibers.

12. The flare of claim 1, wherein (a) said binder comprises at least one member selected from the group consisting of poly-N-vinyl pyrolidone, polyvinylalcohol, copolymers of poly-N-vinyl pyrolidone and polyvinylalcohol, sodium polyacrylates, and gum;

(b) said oxidizer is present in an amount of from about 40% by weight to about 90% by weight relative to the dry ingredients used in formulating said extrudable igniter composition, and said oxidizer contains at least one ionic species selected from the group consisting of nitrate, nitrite, chlorate, perchlorate, peroxides, and superperoxides;

(c) said extrudable igniter composition contains low-aspect ratio fibers, said fibers comprising at least one of polyolefin fibers, polyamide fibers, polyester fibers, and poly(2,2′

-(m-phenylene)-5,5-bisbenzimidazole fibers.

13. The flare of claim 1, wherein said extruded igniter element is in the form of an igniter stick.

14. The flare of claim 1, wherein said fuel comprises boron and said oxidizer comprises potassium nitrate.

15. The flare of claim 14, wherein said water-soluble polymeric binder comprises a polymer or copolymer comprising at least member selected from the group consisting of polyacrylamide, sodium polyacrylates, and copolymers thereof.

16. The flare of claim 15, wherein said boron is present in an amount of about 5% to about 30% by weight, said potassium nitrate is present in an amount of about 40% to about 90% by weight, and the binder is present in an amount of about 2% to about 10% by weight.

17. The flare of claim 16, wherein said extruded igniter element further comprises, as an additional ingredient, guanidine nitrate.

18. A method of forming a flare comprising a case, propellant contained within the case, and an igniter system comprising an extruded dry igniter element deflagrating upon ignition for igniting the propellant of said flare, the extruded dry igniter element being formed from an extrudable igniter composition, said method comprising:

dissolving at least one water-soluble binder into an aqueous solvent,

mixing the dissolved binder with at least one oxidizing agent, at least one fuel, and, optionally, fibers to form the extrudable igniter composition, and

extruding and drying the extrudable igniter composition,

wherein the water-soluble binder comprises at least one member selected from the group consisting of a water-soluble polymeric binder, a water-soluble gum present in an amount of from about 2% by weight to about 10% by weight based on the total amount of dry ingredient in the extrudable igniter composition, and water-soluble gelatin.

19. The method of claim 18, wherein the water-soluble binder comprises at least one member selected from the group consisting of poly-N-vinyl pyrolidone, polyvinylalcohol, copolymers of poly-N-vinyl pyrolidone and polyvinylalcohol, polyacrylamide, sodium polyacrylates, and copolymers of polyacrylamides and sodium polyacrylates.

20. The method of claim 19, wherein the water-soluble binder comprises poly-N-vinyl pyrolidone.

21. The method of claim 19, wherein the water-soluble binder comprises polyvinylalcohol.

22. The method of claim 19, wherein the water-soluble binder comprises gum.

23. The method of claim 19, wherein the water-soluble binder comprises polyacrylamide.

24. The method of claim 18, wherein the oxidizer is present in an amount of from about 40% by weight to about 90% by weight relative to the dry ingredients used in formulating the extrudable igniter composition.

25. The method of claim 18, wherein said oxidizer comprises an organic oxidizer.

26. The method of claim 18, wherein the oxidizer comprises at least one ionic species selected from the group consisting of nitrate, nitrite, chlorate, perchlorate, peroxides, and superperoxides.

27. The method of claim 18, wherein the extrudable igniter composition contains fibers.

28. The method of claim 27, wherein the fibers comprise at least one of polyolefin fibers, polyamide fibers, polyester fibers, or poly(2,2′

-(m-phenylene)-5,5-bisbenzimidazole fibers.

29. The method of claim 28, wherein (a) the binder comprises at least one member selected from the group consisting of poly-N-vinyl pyrolidone, polyvinyl alcohol, copolymers of poly-N-vinyl pyrolidone and polyvinylalcohol, sodium polyacrylates, and gum;

(b) the oxidizer is present in an amount of from about 40% by weight to about 90% by weight relative to the dry ingredients used in formulating the extrudable igniter composition, and the oxidizer contains at least one ionic species selected from the group consisting of nitrate, nitrite, chlorate, perchlorate, peroxides, and superperoxides;

(c) the extrudable igniter composition contains low-aspect ratio fibers, the fibers comprising at least one of polyolefin fibers, polyamide fibers, polyester fibers, and poly(2,2′

-(m-phenylene)-5,5-bisbenzimidazole fibers.

30. The method of claim 18, wherein the extruded igniter element is in the form of an igniter stick.