KOCHETOV SCREW-TYPE SOUND-ABSORBING STRUCTURE Russian patent published in 2017 - IPC E04B1/84 G10K11/16 

FIELD: machine building.

SUBSTANCE: sound absorbing structure is made in the form of two perforated walls, between which the multi-layered sound absorbing element. The multilayer sound absorbing element is double-layered. The layer adjacent to one of the walls is sound-absorbing, and the layer adjacent to the other perforated wall is made of a sound reflecting material consisting of complex profile composed of evenly distributed hollow tetrahedrons, allowing to reflect acoustical surges incident in all directions. Each of the perforated wall has following perforation parameters: hole diameter - 37÷ mm, the percentage of perforations÷ 10%15%. As per shape the holes can be made as holes having round, triangular, square, rectangular or diamond profile. In case of unround holes the nominal diameter shall be maximum diameter of circle inscribed in the polygon. Asa sound-proof material the plates from basalt-based mineral wool like "Rockwool", or "URSA" mineral wool, or basalt cotton wool P-75, or glass-wool with a woven glass liner are used. The sound absorbing element over the full surface is lined with the acoustic transparent material, for example, glass fabric EZ-100 or polymer "poviden".

EFFECT: invention improves the efficiency of noise suppression and reliability of the design as a whole.

4 cl, 1 dwg