METHOD AND APPARATUS FOR COVERING A FASTENER SYSTEM

• US 20150271960A1
• Filed: 05/29/2015
• Published: 09/24/2015
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Yoon, Ilsop Steven, Pate, Kevin Darrell, Pajel, Carissa Ann, Alberts, Todd Michael, Hansen, Darrin Michael
• Granted Patent: US 10,051,767 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B32B 2435/00 Closures, end caps, stoppers
• CPC Class Codes: B32B 37/0076 characterised in that the layers are not bonded on the totality of their surfaces
• CPC Class Codes: B32B 37/12 characterised by using adhesives
• CPC Class Codes: B32B 37/153 at least one layer is extruded and immediately laminated while in semi-molten state
• CPC Class Codes: B32B 37/18 involving the assembly of discrete sheets or panels only
• CPC Class Codes: B64D 45/02 Lightning protectors; Static dischargers in general H01T
• CPC Class Codes: F16B 11/006 by gluing gluing of plastics material B29C65/48
• CPC Class Codes: F16B 33/004 Sealing; Insulation by means of washers F16B43/001
• CPC Class Codes: F16B 37/14 Cap nuts; Nut caps or bolt caps
• CPC Class Codes: H05K 9/0067 Devices for protecting against damage from electrostatic discharge
• CPC Class Codes: H05K 9/0079 Electrostatic discharge protection, e.g. ESD treated surface for rapid dissipation of charges

Abstract

A method and apparatus for covering a fastener system. In one illustrative embodiment, an apparatus comprises a cover. The cover is configured to be placed over a fastener system at a surface of an object in which the fastener system is installed. The cover is comprised of a number of composite materials selected such that the cover is configured to reduce an effect of an electrical discharge, which occurs around the fastener system, on an environment outside the cover.

Claims

1. An apparatus comprising a cover for a protrusion of a fastener and a sealant material, the cover being:

monolithic, composite, nonporous, electrostatically benign, and static dissipative.

2. The apparatus of claim 1, further comprising the cover configured to be placed over a fastener system at a surface of an object in which the fastener system is installed, wherein the cover is comprised of a number of composite materials selected such that the cover is configured to reduce an effect of an electrical discharge, which occurs around the fastener system, on an environment outside the cover.

3. The apparatus of claim 1, wherein an effect of an electrical discharge on an environment outside the cover comprises an undesired release of a number of materials into the environment outside the cover in response to the electrical discharge.

4. The apparatus of claim 1, wherein the composite comprises a pre-impregnated composite fiber.

5. The apparatus of claim 2, wherein the number of composite materials includes at least one of a carbon fiber-reinforced plastic material, a fiber-reinforced polymer, a glass-reinforced plastic, an aramid fiber-reinforced material, a metallic material, a fiberglass material, a plastic material, a thermoplastic material, and a thermoset material.

6. The apparatus of claim 2, wherein the number of composite materials is selected such that at least one electrical property of the cover has a value within a range selected such that the cover is configured to dissipate a static charge.

7. The apparatus of claim 6, wherein the at least one electrical property of the cover includes at least one of an electrical resistance of the cover, an electrical conductivity of the cover, and an electrical resistivity of the cover.

8. The apparatus of claim 1, wherein a fastener system is located in a hole in an object and wherein the cover is configured to substantially prevent at least one of fluid flowing through the hole from flowing into an environment outside the cover and fluid in the environment outside the cover from flowing through the hole.

9. The apparatus of claim 1 further comprising:

the sealant material configured such that, in operation, the sealant material attaches the cover to a surface of an object.

10. The apparatus of claim 1, wherein the cover comprises a flange configured to be attached to a surface of an object by the sealant material.

11. The apparatus of claim 2, wherein the fastener system comprises:

a number of components including at least one of a fastener, a washer, a plate, a spacer, a gasket, a buckle, and a locking device, wherein the fastener is selected from one of a screw, a nut, a bolt, a nail, a rod, a dowel, a pin, a clamp, a grommet, a latch, a peg, a clip, a rod, a zipper, an anchor, a tie, and a tag.

12. The apparatus of claim 2 further comprising:

a coating configured to be applied to at least a portion of the cover such that the coating is configured to dissipate static charge.

13. The apparatus of claim 2 further comprising a coating configured to be applied to at least a portion of the cover such that the coating is configured to reduce a level of corrosion at the surface of the object and provide a path for dissipation of a static charge on a surface of the coating on the cover.

14. A process for covering a fastener system, the process comprising:

placing a sealant material and a cover over a portion, which extends above a surface of an object retaining the fastener system, of the fastener system, such that the cover comprises a monolithic domed form comprising a number of composite materials;

forming a contactless connection between the cover with the fastener system and the object; and

suppressing, using the sealant material and the cover, an effect of an electrical discharge, occurring around the fastener system, on an environment outside the cover.

15. The process of claim 14, further comprising, applying the sealant material over the fastener system at the surface of the object prior to placing the cover over the fastener system.

16. The process of claim 14, further comprising, applying the sealant material inside the cover prior to placing the cover over the fastener system.

17. A process for reducing an effect of an electrical discharge, occurring at a fastener system, on an environment, the process comprising:

selecting an amount of a sealant material and placing the sealant material inside a cover, the cover being a monolithic domed shaped composite;

encircling an exposed portion of the fastener system with the cover;

suppressing an undesired release, in response to the electrical discharge, occurring at the fastener system, of a number of materials into the environment outside the cover.

18. The process of claim 17 further comprising, fabricating the cover as a pre-impregnated composite comprising a number of composite materials comprising at least one of:

a carbon fiber-reinforced plastic material, a fiber-reinforced polymer, a glass-reinforced plastic, an aramid fiber-reinforced material, a metallic material, a fiberglass material, a plastic material, a thermoplastic material, and a thermoset material.

19. The process of claim 17 further comprising, the cover comprising:

an electrical resistivity comprising a volume resistivity of about 1.0×

10⁹ ohm-meters (Ω

-m) or less when measured at about 40 volts (V), and an electrical resistivity comprising a surface resistivity of about 1.0×

10¹¹ ohm per square (Ω

/sq) or less when measured at about 100 volts (V) or less.

20. The process of claim 17 further comprising:

extruding, by placing the cover encircling the fastening system, the sealant material between a flange of the cover and an object retaining the fastener system; and

covering the flange with the sealant material, by fairing the sealant material extruded between the flange of the cover and the object retaining the fastener system, to form a fairing of sealant material from an exterior side of the cover to the object retaining the fastener system and forming a contactless connection between the cover with the fastener system and the object retaining the fastener system.