Sleeved fastener assembly

Patent metadata

Field	Value
Publication number	US-2016261052-A1
Application number	US-201615156071-A
Country	US
Kind code	A1
Filing date	May 16, 2016
Priority date	Feb 4, 2013
Publication date	Sep 8, 2016
Grant date	—

Abstract

A conductive fastener assembly, system, and method are described. The fastener assembly includes a nut having a counterbore formed therein. The counterbore is formed to maintain a sufficient gap between the nut and the protruding end of a fastener sleeve. The nut with the counterbore improves the conductive fastener system such that the need for a solid copper grid and a cap seal is reduced or eliminated.

First claim

What is claimed is:

1 . A method of preparing a conductive sleeved fastening system for use, comprising:
providing a fastener having a fastener head, a fastener shank extending from said fastener head, and a fastener sleeve provided on said fastener shank and a fastener sleeve flare on said fastener sleeve; preparing a nut configured to attach to the fastener shank, by forming a counterbore therein, the counterbore having:
a counterbore diameter sized to maintain a radial gap between an inward-facing surface of the counterbore and an outer surface of the fastener sleeve; and
a counterbore depth sized to maintain an axial gap between a distal end of the fastener sleeve and a bottom surface of the counterbore.

2 . The method of claim 1 , wherein the fastener head and the fastener sleeve flare are formed having a countersink configuration.

3 . The method of claim 1 , wherein the fastener sleeve is configured to extend through a first structure and a second structure, a protruding end of the fastener sleeve extends beyond the second structure.

4 . The method of claim 3 , further comprising the step of arranging a fay seal between the first structure and the second structure, wherein the fay seal is omitted from an area surrounding fastener assembly.

5 . The method of claim 3 , further comprising the step of arranging an expanded metal foil on a top surface of said first structure.

6 . The method of claim 1 , wherein the counterbore is prepared having a fillet between the inward-facing surface and the bottom surface thereof.

7 . The method of claim 1 , further comprising the step of placing a lubricant between the fastener shank and the fastener sleeve, wherein the lubricant is omitted from an interface between the fastener head and the fastener sleeve flare.

8 . A method comprising:
providing a fastener having a fastener head, a fastener shank extending from said fastener head, and a fastener sleeve provided on said fastener shank and a fastener sleeve flare on said fastener sleeve; preparing a nut configured to attach to the fastener shank, by forming a counterbore therein, the counterbore having:
a counterbore diameter sized to maintain a radial gap between an inward-facing surface of the counterbore and an outer surface of the fastener sleeve; and
a counterbore depth sized to maintain an axial gap between a distal end of the fastener sleeve and a bottom surface of the counterbore; and
arranging a fay seal on a surface of at least one of two structures to be fastened together and having aligned holes therein, wherein the fay seal is omitted from an area surrounding the holes.

9 . The method of claim 8 , wherein the fastener head and the fastener sleeve flare are formed having a countersink configuration.

10 . The method of claim 8 , wherein the fastener sleeve is configured to extend through the two structures, a protruding end of the fastener sleeve extending beyond the two structures.

11 . The method of claim 10 , further comprising the step of arranging an expanded metal foil on a top surface of at least one of the two structures.

12 . The method of claim 8 , wherein the counterbore is prepared having a fillet between the inward-facing surface and the bottom surface thereof.

13 . The method of claim 8 , further comprising the step of placing a lubricant between the fastener shank and the fastener sleeve, wherein the lubricant is omitted from an interface between the fastener head and the fastener sleeve flare.

14 . A method comprising:
forming a fastener having a fastener head and a fastener shank extending from the fastener head; arranging a fastener sleeve on the fastener shank; forming a counterbore within a nut, wherein a radius of the counterbore is sized to maintain a radial gap between an inward-facing surface of the counterbore and an outer surface of the fastener sleeve, and wherein a depth of the counterbore is sized to maintain an axial gap between a distal end of the fastener sleeve and a bottom surface of the counterbore; arranging a fay seal on a surface of at least one of two structures to be fastened together, wherein the two structures have aligned holes defined therein, and wherein the fay seal is omitted from an area surrounding the holes.

15 . The method of claim 14 , wherein the fastener head and the fastener sleeve are formed having a countersink configuration.

16 . The method of claim 14 , further comprising forming a fastener sleeve flare on the fastener sleeve.

17 . The method of claim 14 , further comprising arranging an expanded metal foil on a surface of at least one of the two structures.

18 . The method of claim 14 , wherein the counterbore is formed with a fillet between the inward-facing surface and the bottom surface.

19 . The method of claim 14 , further comprising placing a lubricant between the fastener shank and the fastener sleeve, wherein the lubricant is omitted from an interface between the fastener head and a fastener sleeve flare of the fastener sleeve.

20 . The method of claim 14 , wherein at least one of the two structures has an electrical resistance higher than an electrical resistance of the fastener.

Assignees

• Boeing Co

Inventors

• Heeter Russell J
• Nguyen Thu A
• Ward John A
• Porter John R
• Wilkerson Jeffrey A

Classifications

• F16B33/006

  Non-metallic fasteners using screw-thread · CPC title

• H01R4/304 Primary

  having means for improving contact · CPC title

• F16B2001/0064

  Mechanical Engineering · mapped topic

• B64D45/02 Primary

  Lightning protectors; Static dischargers · CPC title

• H01R43/16

  for manufacturing contact members, e.g. by punching and by bending · CPC title