Granted Patent B2

US 7,510,052 · App. 11/726,451 · Granted Mar 31, 2009

Abstract

Claims (29)

1. An acoustic structure that is adapted to be located near a source of noise, said structure comprising:

a honeycomb comprising a first edge to be located nearest said source of noise and a second edge, said honeycomb further comprising a plurality of walls that extend between said first and second edges, said walls defining a plurality of cells wherein each of said cells has a cross-sectional area measured perpendicular to said walls and a depth defined by the distance between said first and second edges;

a septum cap located within at least one of said cells, said septum cap comprising a sheet of acoustic material that has a thickness and a perimeter, said sheet of acoustic material being formed into a resonator portion that has an outer edge located at said walls and a flange portion that extends between said outer edge of said resonator portion and the perimeter of said sheet of acoustic material, said sheet of acoustic material comprising an open mesh fabric, said septum cap comprising an adhesive flow barrier located along said resonator portion, said adhesive flow barrier comprising open mesh fabric that has been flattened; and

an adhesive that bonds said anchoring surface to said wall, said adhesive covering at least a portion of said anchoring surface.

2. An acoustic structure according to claim 1 wherein said woven fibers are monofilament polymer fibers.

3. An acoustic structure according to claim 1 wherein said sheet of acoustic material comprises one or more folding aids located around said perimeter.

4. An acoustic structure according to claim 1 at least two septum are located in said cell, said septum caps being located at different depths within said cell.

5. An acoustic structure according to claim 1 which comprises multiple septum caps that are located in multiple cells wherein the septum caps are located at substantially the same depth within said cells.

6. A power plant system comprising an acoustic structure according to claim 1 that is located near an engine.

7. An aircraft that comprises an acoustic structure according to claim 1 .

8. A power plant system comprising an aircraft engine and a nacelle for said aircraft engine wherein said nacelle comprises an acoustic structure according to claim 1 .

9. An acoustic structure according to claim 1 that additionally comprises a perforated skin attached to the first edge of said honeycomb and a solid skin attached to the second edge of said honeycomb.

10. A power plant system comprising an acoustic structure according to claim 9 that is located near an engine.

11. An aircraft that comprises an acoustic structure according to claim 9 .

12. A power plant system comprising an aircraft engine and a nacelle for said aircraft engine wherein said nacelle comprises an acoustic structure according to claim 9 .

13. A septum cap precursor comprising:

a sheet of acoustic material that has a thickness and a perimeter, said sheet of acoustic material comprising a resonator portion that has an outer edge located and a flange portion that extends between said outer edge of said resonator portion and the perimeter of said sheet of acoustic material, said sheet of acoustic material comprising an open mesh fabric, said sheet of acoustic material comprising an adhesive flow barrier located along said outer edge of said resonator portion, said adhesive flow barrier comprising open mesh fabric that has been flattened.

14. A septum cap precursor according to claim 13 wherein said open mesh fabric comprises monofilament polymer fibers.

15. A septum cap precursor according to claim 13 wherein said sheet of acoustic material comprises one or more folding aids located around said perimeter.

16. A septum cap precursor according to claim 13 wherein the outer edge of said resonator portion is a hexagon.

17. A septum cap precursor according to claim 13 wherein said perimeter is an octagon.

18. A method for making an acoustic structure that is adapted to be located near a source of noise, said method comprising the steps of:

providing a honeycomb comprising a first edge to be located nearest said source of noise and a second edge, said honeycomb further comprising a plurality of walls that extend between said first and second edges, said walls defining a plurality of cells wherein each of said cells has a cross-sectional area measured perpendicular to said walls and a depth defined by the distance between said first and second edges;

providing at least one sheet of acoustic material that has a thickness and a perimeter, said sheet of acoustic material comprising an open mesh fabric, said sheet of acoustic material comprising an adhesive flow barrier, said adhesive flow barrier comprising open mesh fabric that has been flattened;

forming said sheet of acoustic material into a septum cap comprising a resonator portion that has an outer edge and a flange portion that extends between said outer edge of said resonator portion and the perimeter of said sheet of acoustic material wherein said adhesive flow barrier is located along said outer edge of said resonator portion; and

inserting said septum cap into a cell of said honeycomb wherein said flange portion is in contact with said walls; and

adhesively bonding said anchoring flange portion to said walls.

19. A method for making an acoustic structure according to claim 18 wherein said sheet of acoustic material comprises an open mesh fabric comprising woven monofilament fibers that have been flattened within said adhesive flow barrier.

20. A method for making an acoustic structure according to claim 18 wherein said sheet of acoustic material comprises one or more folding aids located around said perimeter.

Assignments (6)