Electric charge dissipation system for aircraft

Patent metadata

Field	Value
Publication number	US-9840338-B2
Application number	US-201213343443-A
Country	US
Kind code	B2
Filing date	Jan 4, 2012
Priority date	Dec 3, 2010
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

A method and apparatus comprising a first composite layer and a second composite layer in which the second composite layer is associated with the first composite layer. The first composite layer and the second composite layer form a structure. The second composite layer has a conductivity configured to dissipate an electric charge on a surface of the structure and limit a flow of an electrical current in the second composite layer in which the electrical current is caused by an electromagnetic event.

First claim

What is claimed is:

1. An apparatus that comprises:
a first composite layer, such that the first composite layer comprises a carbon fiber reinforced material;
a second composite layer co-cured to an interior side of the first composite layer, such that a fuel tank comprises the first composite layer and the second composite layer, and the second composite layer comprises a resin that comprises a resistivity range from 1×10 6 ohms-meters to 1×10 15 ohms-meters and completely covers a surface of the first composite layer and comprises a configuration such that in operation the second composite layer:
dissipates a static electric charge that builds on a surface of an interior of the fuel tank; and
limits a flow of an electrical current, in response to an electromagnetic event distinct from the static electric charge, through the first and second composite layer, such that the configuration of the second composite layer inhibits an electrical discharge into the interior of the fuel tank;

a primer layer, located between the second composite layer and the interior of the fuel tank, configured to dissipate, such that in operation the primer layer dissipates, the static electric charge, and such that the primer layer coats a surface of the second composite layer entirely; and
a sealant layer located between the primer layer and the interior, such that the sealant layer coats a surface of the primer layer entirely.

2. The apparatus of claim 1 , wherein at least one of: the primer layer, and a third composite layer, reduces galvanic corrosion that occurs when a structure other than the fuel tank contacts the fuel tank.

3. The apparatus of claim 1 further comprising:
a number of composite layers located between the first composite layer and the second composite layer.

4. The apparatus of claim 1 , wherein the second composite layer comprises fibers and wherein the fibers are comprised of a material selected from at least one: of glass, carbon, ceramic, silica, organic materials, plastic, a polymer, nylon, and metal.

5. The apparatus of claim 1 , wherein the second composite layer includes a conductive material selected from one of a metal, a metal alloy, nickel, carbon, a conductive polymer, titanium dioxide, and carbon black.

6. The apparatus of claim 1 , wherein the second composite layer comprises fibers comprising at least one of: a conductive material, and a coating comprising a second conductive material.

7. The apparatus of claim 6 , wherein the coating comprises at least one of: a powder that adheres to the fibers, and wherein the powder comprises a nano-powder that adheres to at least a portion of the fibers.

8. The apparatus of claim 1 , wherein the second composite layer comprises fibers that form a reinforcement and the resin that forms a matrix in the reinforcement.

9. The apparatus of claim 8 , wherein the resin provides a conductivity that dissipates the static electric charge on the surface of the fuel tank and limits the flow of the electrical current in the second composite layer.

10. The apparatus of claim 1 , wherein the second composite layer is a fiberglass layer.

11. The apparatus of claim 1 , wherein the second composite layer comprises a prepreg material.

12. The apparatus of claim 1 , further comprising a conductive material selected from a group consisting of: a metal, a metal alloy, nickel, carbon, a conductive polymer, titanium dioxide, and carbon black.

13. The apparatus of claim 1 , further comprising a conductive material comprising carbon black.

14. The apparatus of claim 1 , further comprising the electromagnetic event comprising lightning.

15. The apparatus of claim 1 , further comprising the sealant layer that comprises characteristics that allow application as a post composite cure layer.

16. An electric charge dissipation system for a tank, such that the electric charge dissipation system comprises:
a first composite layer co-cured to an interior side of a second composite layer, such that the first composite layer comprises a carbon fiber material and an external surface of the tank, and the second composite layer comprises:
a second surface, that faces an interior of the tank, of the tank;
a first conductivity sufficient to dissipate an electric charge on an interior surface of the tank; and
a resistivity that ranges from 1×10 6 ohms-meters to 1×10 15 ohms-meters configured to limit, in response to an electromagnetic event distinct from the electric charge, a flow of an electrical current through the second composite layer, such that a configuration of the second composite layer inhibits an electrical discharge into the tank;

a primer layer, located between the second composite layer and the interior of the tank, configured to dissipate the electric charge, and a second resistivity sufficient to inhibit the electrical discharge; and
a sealant layer located between the primer layer and the interior of the tank, such that the sealant layer coats a surface of the primer layer entirely.

17. A tank configured to retain at least one of: a liquid, and a gas, such that the tank comprises:
a first composite layer, such that the first composite layer comprises a carbon fiber reinforced material;
a second composite layer co-cured to the first composite layer, such that the second composite layer comprises a resin configured to dissipates a static electric charge, on a surface of an interior of the tank, via a resistivity range from 1×10 6 ohms-meters to 1×10 9 ohms-meters, and completely covers a surface of the first composite layer; and
a primer layer, located between the second composite layer and the interior of the tank, configured to dissipate, such that in operation the primer layer also dissipates, the static electric charge, on the surface of an interior of the tank, and such that the primer layer coats a surface of the second composite layer entirely; and
a sealant layer located between the primer layer and the interior, such that the sealant layer coats a surface of the primer layer entirely.

18. The tank of claim 17 , further comprising the second composite layer further configured to limit a flow of an electrical current, in response to an electromagnetic event distinct from the static electric charge, through the first and second composite layer, such that a configuration of the second composite layer inhibits an electrical discharge into the interior of the tank, via the resin comprising a resistivity range from 1×10 6 ohms-meters to 1×10 15 ohms-meters.

19. The tank of claim 17 , further comprising the at least one of: the liquid, and the gas, being a volatile fuel.

20. The tank of claim 17 , further comprising the liquid being a fuel for an aircraft.

Assignees

• Gerken Noel Timothy
• Le Quynhgiao Nguyen
• Boeing Co

Inventors

• Gerken Noel Timothy
• Le Quynhgiao Nguyen

Classifications

• B64D37/32

  Safety measures not otherwise provided for, e.g. preventing explosive conditions · CPC title

• B64D45/02 Primary

  Lightning protectors; Static dischargers · CPC title

• Y02T50/44

  Cross-Sectional Technologies · mapped topic

• Y02T50/40

  Weight reduction · CPC title