Composition and process for inflating a safety crash bag

• US 4,948,439 A
• Filed: 01/09/1990
• Issued: 08/14/1990
• Est. Priority Date: 12/02/1988
• Status: Expired due to Term

• Current Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Wilson, Michael A., Poole, Donald R.
• Primary Examiner(s): Lechert, Jr., Stephen J.
• Application Number:
  US07/462,476
• Time in Patent Office: 217 Days
• Field of Search: 149/46, 149/61, 149/76, 149/85, 149/77, 149/83, 280/728, 280/741, 280/736, 252/182.31, 252/350
• US Class Current: 149/46
• CPC Class Codes: B60R 21/30 with means to draw ambient air into the flow line and mix such air with the inflation fluid
• CPC Class Codes: C06D 5/06 by reaction of two or more solids

Abstract

Composition and process for inflating an automobile or aircraft safety crash bag comprising igniting at elevated pressure a pyrotechnic material comprising at least one tetrazole or triazole compound containing hydrogen in the molecule, at least one oxygen containing oxidizer compound, and at least one metal oxide to generate a gas which is admixed with air by means of an aspirating venturi and thereafter utilized to inflate the crash bag.

Claims

1. A method for inflating an automobile or aircraft safety crash bag comprising the combustion of a pyrotechnic material, comprising at least one tetrazole or triazole compound containing hydrogen in the molecule, to generate substantially non-toxic combustion products including a gas to inflate said crash bag, said method comprising:

(a) burning said pyrotechnic material at elevated pressure in admixture with at least one oxygen containing oxidizer compound and at least one metal oxide so as to produce, upon combustion, a substantially non-toxic primary gas mixture and easily filterable solids; and

(b) diluting said primary gas mixture with air to produce a substantially non-toxic final gas mixture by passing said primary gas mixture through at least one venturi so as to aspirate said air, whereby said crash bag, when inflated, contains a final gas mixture comprising about 1 to about 4 volumes of air per volume of said primary gas mixture.

2. The method of claim 1 whereby said easily filterable solids produced upon combustion comprise at least one of metal silicates, ferrates, cobaltates, nickelates, chromates, aluminates, borates, and vanadates.

3. The method of claim 2 whereby said metal oxides are selected from the group consisting of silicon dioxide, iron oxide, cobalt oxide, nickel oxide, chromium oxide, aluminum oxide, boron oxide, and vanadium oxide.

4. The method of claim 3 whereby said oxygen containing oxidizer compound is selected from at least one of the group consisting of alkali metal, alkaline earth metal and ammonium oxygen containing oxidizer salts.

5. The method of claim 4 whereby said tetrazole compound is selected from the group consisting of a hydrogen containing tetrazole, an aminotetrazole, metal salts thereof, and mixtures thereof.

6. The method of claim 5 whereby said oxygen containing oxidizer compound is selected from at least one of the group consisting of alkali metal, alkaline earth metal, and ammonium nitrates or perchlorates.

7. The method of claim 6 whereby said tetrazole compound is an alkali metal, alkaline earth metal, or ammonium salt of a hydrogen containing tetrazole which is present in a concentration of about 20 to about 60% by weight, said oxygen containing oxidizer compound is present in an amount of about 20 to about 80% by weight, and said metal oxide is silicon dioxide, present in an amount of about 2 to about 20% by weight.

8. The method of claim 7 whereby said primary gas mixture upon dilution with about 1 to about 4 volumes of air per volume of said primary gas mixture comprises about 2 to about 10 by volume of carbon dioxide, less than about 4% by volume of hydrogen, and less than about 50% by volume of water.

9. A gas mixture suitable for inflating an automobile or aircraft safety crash bag prepared by the process of claim 1.

10. An aircraft or automobile safety crash bag inflated with a gas mixture prepared by the process of claim 1.

11. A pyrotechnic mixture useful to generate substantially non-toxic combustion products including a gas to inflate a crash bag, said pyrotechnic mixture comprising at least one tetrazole compound containing hydrogen in the molecule or a triazole compound containing hydrogen in the molecule, each in admixture with at least one oxygen containing oxidizer compound and at least one metal oxide so as to produce, upon combustion, a substantially non-toxic primary gas mixture and easily filterable solids.

12. The composition of claim 11 wherein said oxygen containing oxidizer compound is selected from at least one of the group consisting of alkali metal, alkaline earth metal, and ammonium oxygen containing oxidizer salts and said metal oxide is selected from the group consisting of silicon dioxide, iron oxide, cobalt oxide, nickel oxide, chromium oxide, aluminum oxide, boron oxide, and vanadium oxide.

13. The composition of claim 12 wherein said tetrazole compound is selected from the group consisting of a hydrogen containing tetrazole, an aminotetrazole, metal salts thereof, and mixtures thereof.

14. The composition of claim 13 wherein said oxygen containing oxidizer is selected from at least one of the group consisting of alkali metal, alkaline earth metal, and ammonium nitrates or perchlorates.

15. The composition of claim 14 wherein said primary gas mixture, upon dilution with about 1 to about 4 volumes of air per volume of said primary gas mixture, comprises, by volume, about 2 to about 10% carbon dioxide, less than about 4% hydrogen, and less than 50% water.

16. The composition of claim 15 wherein said tetrazole compound is an alkali metal, an alkaline earth metal, or ammonium salt of a hydrogen containing tetrazole which is present in a concentration of about 20 to about 60% by wt., said oxygen containing oxidizer compound is present in an amount of about 20 to about 80% by wt., and said metal oxide is present in an amount of about 2 to about 20% by wt.

17. The composition of claim 16 wherein said pyrotechnic mixture comprises about 40% by wt. of the sodium salt of tetrazole, about 50% by wt. sodium nitrate, and about 10% by wt. of silicon dioxide.

18. The composition of claim 16 wherein said pyrotechnic mixture comprises about 30% by wt. of 5-aminotetrazole, about 54% by wt. of potassium nitrate, and about 16% by wt. of silicon dioxide.

19. The composition of claim 16 wherein said pyrotechnic mixture comprises about 21% by wt. of 5-aminotetrazole, about 35% by wt. of ammonium perchlorate, about 41% by wt. of potassium nitrate, and about 3.2% by wt. of silicon dioxide.