Micro thrust and heat generator

• US 5,836,150 A
• Filed: 05/31/1995
• Issued: 11/17/1998
• Est. Priority Date: 05/31/1995
• Status: Expired due to Fees

• Current Assignee: United States Department of Energy (Government of the United States of America)
• Original Assignee: United States Department of Energy (Government of the United States of America)
• Inventors: Garcia, Ernest J.
• Primary Examiner(s): FREAY, CHARLES GRANT
• Application Number:
  US08/456,993
• Time in Patent Office: 1,266 Days
• Field of Search: 60/251, 60/253, 60/256, 60/39.821, 60/39.827
• US Class Current: 60/256
• CPC Class Codes: B64G 1/26 using jets
• CPC Class Codes: B64G 1/4005 Air-breathing propulsion
• CPC Class Codes: B64G 1/401 Liquid propellant rocket engines Ion or plasma engines B64G1/413; Arcjets and other resistojets B64G1/415
• CPC Class Codes: B64G 1/415 Arcjets or resistojets
• CPC Class Codes: F01D 15/00 Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
• CPC Class Codes: F02K 9/08 using solid propellants F02K9/72 takes precedence; using semi-solid or pulverulent propellants F02K9/70
• CPC Class Codes: F02K 9/42 using liquid or gaseous propellants F02K9/72 takes precedence
• CPC Class Codes: F02K 9/95 characterised by starting or ignition means or arrangements safety devices F02K9/38
• CPC Class Codes: F05D 2250/82 Micromachines
• CPC Class Codes: F05D 2250/84 Nanomachines
• CPC Class Codes: F15C 5/00 Manufacture of fluid circuit elements; Manufacture of assemblages of such elements integrated circuits

Abstract

A micro thrust and heat generator has a means for providing a combustion fuel source to an ignition chamber of the micro thrust and heat generator. The fuel is ignited by a ignition means within the micro thrust and heat generator'"'"'s ignition chamber where it burns and creates a pressure. A nozzle formed from the combustion chamber extends outward from the combustion chamber and tappers down to a narrow diameter and then opens into a wider diameter where the nozzle then terminates outside of said combustion chamber. The pressure created within the combustion chamber accelerates as it leaves the chamber through the nozzle resulting in pressure and heat escaping from the nozzle to the atmosphere outside the micro thrust and heat generator. The micro thrust and heat generator can be microfabricated from a variety of materials, e.g., of polysilicon, on one wafer using surface micromachining batch fabrication techniques or high aspect ratio micromachining techniques (LIGA).

Claims

1. A micro thrust and heat generator developed using a polysilicon surface micromachining batch-fabricated technique comprising:

a substrate base comprising at least single crystal silicon material;

an ignition chamber formed on said substrate base;

a delivery means formed on said substrate base for providing a fuel source to said ignition chamber;

an ignition means formed on said substrate base for igniting a fuel source within said ignition chamber; and

a convergent-divergent nozzle formed on said substrate base and extending outward from said ignition chamber for receiving a high-flow gas stream generated from said ignition means within said ignition chamber.

2. The invention of claim 1 wherein said ignition chamber contains said ignition means and said means for providing a combustion fuel source, and said convergent-divergent nozzle provides an opening for said combustion chamber.

3. The invention of claim 2 wherein said ignition means comprises an electrical ignition element further comprising at least a pair of electrodes located within the ignition chamber whereby said fuel is ignited by an electrical breakdown between said pair of electrodes.

4. The invention of claim 2 wherein said fuel delivery means comprises at least one inlet tube for transporting said fuel source to said ignition chamber.

5. The invention of claim 2 wherein said convergent-divergent nozzle extends outward from said ignition chamber and terminates at an exhaust port opening outside of said ignition chamber whereby the pressure and heat created within the ignition chamber resulting from the combustion of said fuel source by said ignition means accelerates a gas through said convergent-divergent nozzle and through said exhaust pot opening to ambient.

6. The invention of claim 5 wherein said ignition means comprises an electrical ignition element further comprising a pair of electrodes located within the ignition chamber whereby combustible fuel is ignited by an electrical breakdown between said pair of electrodes.

7. The invention of claim 6 wherein said combustible fuel source provided to said ignition chamber by said tube inlet means comprises a gas.

8. The invention of claim 6 wherein said combustible fuel source provided to said ignition chamber by said delivery means comprises a liquid.

9. The invention of claim 5 wherein said ignition means comprises an electrical ignition element further comprising a resistive heating igniter located within said ignition chamber.

10. The invention of claim 9 wherein said fuel source comprises a solid combustible fuel disposed within said ignition chamber for combustion within said ignition chamber.

13. The invention of claim 1 wherein said fuel delivery means, said ignition chamber, and convergent-divergent nozzle are fabricated from a material of the class consisting of polysilicon, silicon carbide, and silicon nitride.

14. The invention of claim 1 wherein said ignition means formed on said substrate base for igniting said fuel source within said ignition chamber comprises a material of the class consisting of tungsten, platinum, nickel, iron, iron-nickel, and alloys thereof.

11. The claim of invention 2 wherein said fuel source comprises a solid combustible fuel disposed within said ignition chamber for combustion within said ignition chamber.

12. The invention of claim 11 wherein said ignition means comprises a resistive heating ignitor.

15. A micro thrust and heat generator for generating heat and propulsion in the microdomain and developed using a polysilicon surface micromachining batch-fabricated technique comprising:

a substrate base;

an ignition chamber formed on said substrate base to contain the combustion of a fuel source;

a delivery means formed on said substrate base for providing a fuel source to said ignition chamber;

an ignition means formed on said substrate base for igniting said fuel source within said ignition chamber; and

a converging-diverging nozzle formed on said substrate base and directly extending from said ignition chamber for receiving a high-flow gas stream produced by said ignition means wherein the heat and said gas stream propulsion exits said converging-diverging nozzle to ambient.

16. The invention of claim 15 wherein said fuel source comprises a gas.

17. The invention of claim 15 wherein said fuel source comprises a liquid propellant.

18. The invention of claim 15 wherein said delivery means comprises at least one inlet tube formed on said substrate base for transporting said fuel source to said ignition chamber.

19. The invention of claim 15 wherein said ignition means comprises an electrical element further comprising at least one pair of electrodes formed on said substrate base within said ignition chamber and wherein spontaneous combustion is caused by an electrical breakdown between said pair of electrodes.

20. The invention of claim 19 wherein said electrical ignition means for igniting said fuel source within said ignition chamber further comprises a platinum glow-plug-type catalyst formed on said substrate base.

21. The invention of claim 15 wherein said ignition means for igniting said fuel source within said ignition chamber comprises a resistive heating igniter.

22. The invention of claim 15 wherein said fuel delivery means, said ignition chamber, and convergent-divergent nozzle are fabricated from a material of the class consisting of polysilicon, silicon carbide, and silicon nitride.

23. The invention of claim 15 wherein said ignition means formed on said substrate base for igniting said fuel source within said ignition chamber comprises a material of the class consisting of tungsten, platinum, iron, nickel, iron-nickel, and alloys thereof.