FLEX CIRCUIT LIGHTNING PROTECTION APPLIQUE SYSTEM FOR SKIN FASTENERS IN COMPOSITE STRUCTURES

• US 20070230085A1
• Filed: 12/20/2006
• Published: 10/04/2007
• Est. Priority Date: 03/29/2006
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Le, Quynhgiao N.
• Granted Patent: US 7,869,181 B2
• Time in Patent Office: Days
• US Class Current: 361/212
• CPC Class Codes: B64D 45/02 Lightning protectors; Static dischargers in general H01T
• CPC Class Codes: H02G 13/00 Installations of lightning conductors; Fastening thereof to supporting structure
• CPC Class Codes: H02G 13/40 Connection to earth
• CPC Class Codes: H02G 13/80 Discharge by conduction or dissipation, e.g. rods, arresters, spark gaps
• CPC Class Codes: H05K 1/0254 High voltage adaptations; Electrical insulation details; Overvoltage or electrostatic discharge protection electrostatic discharge protection for electric apparatus in general H05K9/0067, H05K9/0079; Arrangements for regulating voltages or for using plural voltages
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups

Abstract

A lightning protection appliqué incorporates a plurality of conductive plies adhesively affixed to a composite surface, at least a first one of the plies providing conductive characteristics sufficient to divert electrical energy from a lightning strike and at least a second one of the plies comprising operational circuitry. A dielectric ply is fixed to the composite surface over and completely covering at least one metal surface feature between the plurality of conductive plies and the composite surface.

Claims

1. A lightning protection appliqué

comprising;

a plurality of conductive plies adhesively affixed to a composite surface, at least a first one of said plies having conductive characteristics sufficient to divert electrical energy from a lightning strike and at least a second one of said plies comprising operational circuitry;

a dielectric ply fixed to the composite surface over and completely covering at least one metal surface feature intermediate said plurality of conductive plies and said composite surface.

2. A lightning protection appliqué

as defined in claim 1 wherein each conductive ply incorporates a conductive layer and a dielectric layer intermediate the conductive layer and an adjacent conductive ply.

3. A lightning protection appliqué

as defined in claim 1 wherein a bottom conductive ply incorporates an attachment backing layer for securing said plurality of conductive plies to the composite surface and the dielectric ply.

4. A lightning protection appliqué

as defined in claim 1 wherein said first one of said conductive plies is connected to a platform ground.

5. A lightning protection appliqué

as defined in claim 1, wherein the conductive layer of said first one of said conductive plies comprises a 0.0007″

(0.018 mm) thick minimum metal conductor.

6. A lightning protection appliqué

as defined in claim 1, wherein said dielectric ply comprises;

a layer of said dielectric film; and

a pressure sensitive adhesive layer attaching said layer of dielectric film to said composite surface.

7. A lightning protection appliqué

as in claim 6, wherein said dielectric film is a film of dielectric material selected from a group of materials consisting of a fluoropolymer, a polyester, a polyimide, and polyurethane.

8. A lightning protection appliqué

as defined in claim 2, wherein said dielectric layer in each said conductive ply is selected from a group of materials consisting of a fluoropolymer, a polyester, a polyimide, and polyurethane.

9. A lightning protection appliqué

as defined in claim 1, further comprising;

a platform ground; and

an external connection to said platform ground, said first of said conductive plies contacting said external connection, current from lightning strikes dispersing through said platform ground.

10. A lightning protection appliqué

as defined in claim 1 wherein the operational circuitry of said second one of said conductive plies is a deicing heater element.

11. A lightning protection appliqué

as defined in claim 1 wherein the operational circuitry of said second one of said conductive plies is an antenna.

12. A lightning protection appliqué

as defined in claim 1 wherein the operational circuitry of said second one of said conductive plies is a sensor.

13. An aircraft lightning protection system comprising:

an appliqué

having a plurality of conductive plies adhesively affixed to a composite surface on an aircraft, at least a first one of said plies having conductive characteristics sufficient to divert electrical energy from a lightning strike and at least a second one of said plies comprising operational circuitry for electrical interconnection with aircraft systems;

a dielectric ply fixed to the composite surface over and completely covering at least one metal surface feature on the aircraft, said dielectric ply intermediate said plurality of conductive plies and said composite surface.

14. An aircraft lightning protection system as defined in claim 13 wherein each conductive ply incorporates a conductive layer and a dielectric layer intermediate the conductive layer and an adjacent conductive ply.

15. An aircraft lightning protection system as defined in claim 13 wherein a bottom conductive ply of the appliqué

incorporates an attachment backing layer for securing said plurality of conductive plies to the composite surface and the dielectric ply.

16. An aircraft lightning protection system as defined in claim 13, wherein the conductive layer of said first one of said conductive plies comprises a 0.0007″

(0.018 mm) thick minimum metal conductor.

17. An aircraft lightning protection system as defined in claim 13, wherein said dielectric ply comprises:

a layer of said dielectric film; and

a pressure sensitive adhesive layer attaching said layer of dielectric film to said composite surface.

18. An aircraft lightning protection system as in claim 17, wherein said dielectric film is a film of dielectric material selected from a group of materials consisting of a fluoropolymer, a polyester, a polyimide, and polyurethane.

19. An aircraft lightning protection system as defined in claim 14, wherein said dielectric layer in each said conductive ply is selected from a group of materials consisting of a fluoropolymer, a polyester, a polyimide, and polyurethane.

20. An aircraft lightning protection system as defined in claim 13, further comprising:

a platform ground; and

an external connection to said platform ground, said first one of said conductive plies contacting said external connection to direct current from lightning strikes to disperse through said platform ground.

21. An aircraft lightning protection system as defined in claim 13 wherein the operational circuitry of said second one of said conductive plies is a deicing heater element.

22. An aircraft lightning protection system as defined in claim 13 wherein the operational circuitry of said second one of said conductive plies is an antenna.

23. An aircraft lightning protection system as defined in claim 13 wherein the operational circuitry of said second one of said conductive plies is a sensor.

24. A method for lightning protection of an aircraft comprising the steps of:

providing a dielectric ply;

fixing said dielectric ply to a composite surface over and completely covering at least one metal surface feature on the aircraft;

providing an appliqué

having a plurality of conductive plies, at least a first one of said plies having conductive characteristics sufficient to divert electrical energy from a lightning strike and at least a second one of said conductive plies comprising operational circuitry for electrical interconnection with aircraft systems;

adhesively affixing said appliqué

to the composite surface of the aircraft completely covering said dielectric ply;

connecting said second one of said conductive plies to an electrical system on the aircraft.

25. A method as defined in claim 24 wherein the step of providing and appliqué

includes the steps of

assembling for each conductive ply in the appliqué

a conductive layer and a dielectric layer intermediate the conductive layer and an adjacent conductive ply.

26. A method as defined in claim 24 wherein the step of adhesively affixing the appliqué

further includes the steps of

providing an external connection to a platform ground; and

connecting said first one of said conductive plies to said external connection to direct current from lightning strikes to disperse through said platform ground.

27. A method as defined in claim 24 wherein the operational circuitry comprises a deicing heater element and the step of connecting said second one of said conductive plies comprises connecting a current source and control to said second one of the conductive plies for aircraft deicing.