Panel fastener, panel assembly and methods of assembly and installation

1. A fastener assembly comprising a sleeve with a sleeve wall extending longitudinally and having a channel within the sleeve wall, wherein the sleeve wall has proximal and distal end portions, wherein the sleeve wall includes a wall defining an opening through the sleeve wall, a fastener receptacle element having proximal and distal end portions and wherein the fastener receptacle element is at least partly within the sleeve and with at least one internally, at least partially-threaded wall configured to receive a threaded fastener element, wherein at least one of the sleeve and the fastener receptacle element includes a flange portion at the proximal end portion extending radially outward relative to a central axis of the fastener assembly, and wherein the fastener receptacle element includes at least one flexible leg element extending from a proximal portion to a free distal end portion and configured such that during assembly the free end portion is inserted in a distal direction at the sleeve proximal portion longitudinally into the sleeve until part of the free end portion extends within the sleeve opening so that the fastener receptacle element is axially movable within the sleeve, wherein the free distal end portion of the flexible leg element is positioned on the fastener receptacle element opposite the flange portion, and wherein the sleeve includes a distal portion extending beyond the at least one flexible leg element.

2. The assembly of claim 1 wherein the wall defining the opening through the sleeve wall has a closed perimeter.

3. The assembly of claim 1 wherein the at least one internally threaded wall is formed on an inside surface of the at least one flexible leg element and the threads extend the entire length of the at least one flexible leg.

4. The assembly of claim 1 wherein the sleeve includes a surface complimentary to an externally adjacent surface.

5. The assembly of claim 1 wherein the at least one flexible leg on the fastener receptacle element extends along a longitudinal axis and includes a thickness that increases in a longitudinal direction and wherein the thickness increases in a direction only outward and away from threads on the at least one flexible leg.

6. The assembly of claim 1 wherein the at least one flexible leg includes a first portion having threads and wherein the first portion and the threads form a substantially constant thickness, and the at least one flexible leg includes a second portion having threads wherein the second portion and the threads form a thickness that increases in the longitudinal direction.

7. The assembly of claim 1 wherein the sleeve includes a head and the fastener receptacle element proximal end includes a shoulder extending laterally, the shoulder contacting the sleeve head.

8. A fastener assembly comprising a sleeve with a sleeve wall extending longitudinally and having a channel within the sleeve wall and wherein the sleeve wall includes a wall defining an opening through the sleeve wall, a fastener receptacle element at least partly within the sleeve and with at least one internally, at least partially-threaded wall configured to receive a threaded fastener element, and wherein the fastener receptacle element includes at least one flexible leg element extending from a proximal portion to a free distal end portion and configured such that during assembly the free end portion is inserted in a distal direction longitudinally into the sleeve until part of the free end portion extends within the sleeve opening so that the fastener receptacle element is axially movable within the sleeve, and wherein the sleeve includes a distal portion extending beyond the at least one flexible leg element, wherein the sleeve includes a surface complimentary to an externally adjacent surface and wherein the adjacent surface is an insert adapted to be placed in the panel portion and substantially fixed relative to the panel portion.

9. The assembly of claim 8 wherein the insert is a first insert and further including a second insert contacting the first insert and wherein the first and second inserts include rotation-limiting portions configured to limit relative rotation between the first and second inserts.

10. The assembly of claim 9 wherein at least one of the first and second inserts includes a sealing element.

11. A method of assembling a panel structure for installation onto an aircraft structure for supporting the panel, the method comprising assembling into the panel before moving the panel structure into final position on an aircraft at least first and second fastener assemblies each having a nut element, a sleeve element extending adjacent a respective nut element and beyond the respective nut element and the panel, and male threaded fastener elements threaded into respective nut elements.

12. The method of claim 11 further including securing a first insert having an insert opening in an opening formed in the panel, and placing a second insert against the first insert, such that placing the second insert against the first insert limits relative rotation between the first and second inserts.

13. The method of claim 12 wherein placing the second insert secures the nut element to the panel structure.

14. The method of claim 11 further including inserting a sleeve element into an opening through the panel.

15. The method of claim 11 wherein the nut element extends into a sleeve element having an opening and wherein the nut element includes a projection that extends into the opening and contacts directly or indirectly a surface of the aircraft structure and wherein the opening in the sleeve element is an enclosed-wall opening and the projection on the nut element extends into the opening to contact directly or indirectly the surface of the aircraft structure.

16. The method of claim 11 further including moving the panel containing the first and second fastener assemblies into position on the aircraft structure and thereafter threading the male threaded fasteners into respective nut elements so that the nut elements secure a portion of the panel to the aircraft structure.