Metal attachment

Patent metadata

Field	Value
Publication number	US-10851825-B2
Application number	US-201414906258-A
Country	US
Kind code	B2
Filing date	Jul 21, 2014
Priority date	Jul 19, 2013
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

The invention concerns a metal attachment for providing an electrically conductive surface through the entire thickness of structural elements to be assembled. The attachment thereby comprises a head (12) and a smooth shank (14) extending along an axis of revolution, characterized in that the shank comprising at least one conductive portion (24) and one lubricating portion (22) disposed along the axis of revolution of the attachment along at least one length of the shank. The attachment according to the invention provides a conductive surface through the entire thickness of the structure in which it is installed. The attachment according to the invention is intended, in particular, for aeronautical applications.

First claim

The invention claimed is:

1. A metal fastener comprising an expanded head and a smooth shank extending in an axis of revolution, wherein the shank has a shank surface that comprises at least one conductive portion and at least one lubricating portion, disposed continuously along the axis of revolution of the fastener, wherein the shank at least one conductive portion and at least one lubricating portion are disposed continuously and parallel along the axis of revolution of the fastener, wherein the smooth shank comprises a cylindrical shaft, and the at least one conductive portion is a bare metal portion.

2. A metal fastener according to claim 1 , wherein the conductive and lubricating portions are disposed parallel to the axis of revolution of the fastener.

3. A metal fastener according to claim 2 , wherein at least two lubricating portions are disposed in diametrically opposite fashion relative to the axis of revolution of the fastener.

4. A metal fastener according to claim 1 , wherein the conductive and lubricating portions are disposed helically around the axis of revolution of the fastener.

5. A metal fastener according to claim 1 , wherein the bare metal portion is covered with an electrically conductive layer.

6. A metal fastener according to claim 5 , wherein the bare metal portion comprises titanium.

7. A metal fastener according to claim 6 , wherein the bare metal portion comprises titanium oxidized by sulphuric acid anodizing.

8. A metal fastener according to claim 5 , wherein the conductive portion is an electrically conductive layer formed of aluminum.

9. A metal fastener according to claim 5 , wherein the conductive portion is an electrically conductive layer formed as a conductive organic coating.

10. A metal fastener according to claim 1 , wherein the lubricating portion is a solid lubricating film or an organic resin coating comprising aluminum pigments.

11. A metal fastener according to claim 7 , wherein the lubricating portion has a thickness of 5 to 13 microns.

12. A metal fastener of claim 8 , wherein the lubricating coating comprises phenolic resin.

13. A metal fastener according to claim 1 , further comprising a metal sleeve of which an inner diameter is less than an outer diameter of the fastener's shank.

14. A metal fastener according to claim 1 , further comprising a locking portion having a thread or lock grooves.

15. The metal fastener of claim 1 wherein the at least conductive portion is surface-treated by means of anode oxidation.

16. A metal fastener of claim 15 , wherein the cylindrical shaft comprises a plurality of conductive portions that are surface-treated by means of anode oxidation, and a plurality of lubricating portions, the conductive and lubricating portions extending over angular sectors that are distributed around the periphery of the cylindrical shaft.

17. A metal fastener of claim 16 , wherein the conductive and lubricating portions are distributed in a substantially uniform manner around the periphery of the cylindrical shaft.

18. A metal fastener of claim 17 wherein the cylindrical shaft comprises four conductive portions that are surface-treated by means of anode oxidation, each over four angular sectors of an angle substantially 45°, respectively, and that are separated in pairs by means of the lubricating coating and extends over an angular sector of an angle of substantially 45°.

19. A metal fastener of claim 1 , wherein the cylindrical shaft comprises a plurality of conductive portions that are bare metal portions, and a plurality of lubricating portions, the conductive and lubricating portions extending over angular sectors that are distributed around the periphery of the cylindrical shaft.

20. A metal fastener of claim 19 , wherein the conductive and lubricating portions are distributed in a substantially uniform manner around the periphery of the cylindrical shaft.

21. A metal fastener of claim 20 wherein the cylindrical shaft comprises four conductive portions that are bare metal portions, each over four angular sectors of an angle substantially 45°, respectively, and that are separated in pairs by means of the lubricating coating and extends over an angular sector of an angle of substantially 45°.

22. An aircraft assembly, comprising a first component, a second component, and a metal fastener of claim 1 with the metal fastener comprising the at least one conductive portion and the at least one lubricating portion extending continuously along the axis of revolution of the fastener.

23. The aircraft assembly of claim 22 wherein the cylindrical shaft comprises a plurality of conductive portions that are bare metal portions and a plurality of lubricating portions, the conductive and lubricating portions extending over angular sectors that are distributed around the periphery of the cylindrical shaft.

24. The aircraft assembly of claim 23 , wherein the bare metal portions are oxidized by sulfuric acid anodizing.

Assignees

• Lisi Aerospace

Inventors

• Regnard Benoit
• Goyer Julien
• Broucke Martial

Classifications

• C25D11/022

  Anodisation on selected surface areas · CPC title

• F16B25/0021 Primary

  the material being metal, e.g. sheet-metal or aluminium (F16B25/0031 takes precedence) · CPC title

• B64D45/02

  Lightning protectors; Static dischargers · CPC title

• F16B33/06 Primary

  Surface treatment of parts furnished with screw-thread, e.g. for preventing seizure {or fretting (corrosion preventing means F16B33/008; settable coatings for locking threaded members F16B39/225; deformable coatings for locking threaded members F16B39/34)} · CPC title

• F16B33/006

  Non-metallic fasteners using screw-thread · CPC title