Patent ID: 6186270
Filing Date: 2001-02-13
Classification: G10K

Abstract:
A layered absorber for absorbing acoustical sound waves comprising a plurality of layers with at least one layer being spaced apart from another layer by spacers, and at least one layer having a thickness between 0.01 and 5 mm, such spacers being spaced apart from each other between said layers such that gas-filled chambers are formed, wherein said chambers form resonance chambers for acoustic sound waves by tuning the mass-spring pairs of said resonance chambers such that one maximum per mass-spring pair appears in the absorption curve, and wherein a multiple of parallel resonance chambers of a variety of different dimensions of said parallel resonance chambers are formed by varying at least one of the lateral dimensions of said parallel resonance chambers, the densities of the materials of the walls of said parallel resonance chambers, the thicknesses of the walls of said parallel resonance chambers, the rigidity of the materials of the walls of said parallel resonance chambers, and the heights of the said parallel resonance chambers in order to reach different sound absorptions in the respective absorption spectra.