Sandwich panel for sound absorption

Abstract

An aircraft cabin panel for sound absorption, with a core layer that comprises a plurality of cells that extend in an open manner across the thickness of the core layer and that are separated from each other by cell walls, and with a first cover layer that faces away from the sound field, as well as a second cover layer that faces towards the sound field and that comprises a plurality of perforation holes. The second cover layer is multi-layered and apart from a layer with the perforation also comprises a second layer that acts as a flow resistance device. The second layer is arranged on the outside, and visually closes off the perforation, and the outer layer comprises an air-permeable woven fabric.

1 . An aircraft cabin panel for sound absorption, comprising:
 a core layer that comprises a plurality of cells that extend in an open manner across the thickness of the core layer and that are separated from each other by cell walls, and comprising a first cover layer that faces away from the sound field, and a second cover layer that faces towards the sound field and that comprises a plurality of perforation holes, wherein the second cover layer is multi-layered and wherein the second cover layer apart from a layer with the perforation also comprises a second layer that acts as a flow resistance device;   wherein the second layer is arranged on the outside, and visually closes off the perforation; and   wherein the outer layer comprises an air-permeable woven fabric.   
   
   
       2 . The aircraft cabin panel of  claim 1 , wherein the cells of the core layer are at least one of tubular or honeycomb-shaped. 
   
   
       3 . The aircraft cabin panel of  claim 1 , wherein the cover layer perforation comprises a distance between holes that is shorter than the opening width of the honeycomb-like core structure. 
   
   
       4 . The aircraft cabin panel of  claim 1 , wherein the perforated layer is multi-layered, and comprises a first layer that determines the strength, and a second layer comprising at least one of a perforated film or foil. 
   
   
       5 . The aircraft cabin panel of  claim 4 , wherein the first layer comprises a lattice prepreg. 
   
   
       6 . The aircraft cabin panel of  claim 1 , wherein the hollow spaces of the core layer differ in height. 
   
   
       7 . The aircraft cabin panel of  claim 1 , wherein further layers are provided between the first cover layer and the second cover layer. 
   
   
       8 . The aircraft cabin panel of  claim 1 , wherein at least some of the hollow spaces of the core layer are filled with a porous sound-absorbent material. 
   
   
       9 . The aircraft cabin panel of  claim 1 , wherein the cell walls are perforated so that they are acoustically transparent in the direction parallel to the cover layers. 
   
   
       10 . The aircraft cabin panel of  claim 1 , wherein the cover layers comprise fibre reinforced materials. 
   
   
       11 . A device for sound absorption in an aircraft cabin in which between an aircraft supporting structure and a cabin space an interior lining arrangement formed by panels is provided, wherein at least some of the panels comprise sound-absorbent aircraft cabin panels comprising:
 a core layer that comprises a plurality of cells that extend in an open manner across the thickness of the core layer and that are separated from each other by cell walls, and comprising a first cover layer that faces away from the sound field, and a second cover layer that faces towards the sound field and that comprises a plurality of perforation holes, wherein the second cover layer is multi-layered and wherein the second cover layer apart from a layer with the perforation also comprises a second layer that acts as a flow resistance device;   wherein the second layer is arranged on the outside, and visually closes off the perforation; and   wherein the outer layer comprises an air-permeable woven fabric.