SOUND ABSORBING ELEMENT Russian patent published in 2014 - IPC E04B1/84 

FIELD: machine building.

SUBSTANCE: multilayer sound absorbing structure is placed in a sound absorbing element comprising a smooth surface and a perforated surface. The element is made as rigid and perforated walls, between which the layers of sound reflecting, and sound-proof materials of different density arranged in two layers are located. The layers of sound reflecting material are of complex profile composed of evenly distributed hollow tetrahedrons. The layers of sound reflecting material are made from heat insulation material, plates of basalt-based mineral wool like "Rockwool", or "URSA" mineral wool, or basalt wool of P-75 type, or glass wool lined with a glass felt are used as the above material.

EFFECT: enhanced efficiency of sound absorption and reliability of the structure in general.

4 cl, 1 tbl, 1 dwg