SOUND ABSORBING STRUCTURE Russian patent published in 2016 - IPC E04B1/84 G10K11/16 

FIELD: acoustics.

SUBSTANCE: invention relates to industrial acoustics and can be used for machine drive noise reduction, lining manufacturing facilities. Sound absorbing structure is made in form of symmetrically arranged perforated walls, between which sound-absorbing element made up of three layers: central layer from sound reflecting material from complex profile composed of evenly distributed hollow tetrahedrons, which enable to reflect sound waves incident in all directions, and symmetrically adjacent thereto sound-absorbing layers from materials of different density. Each of perforated walls has following perforation parameters: hole diameter of 3÷7 mm, perforation percentage of 10÷15 %. As for the shape the holes can be circular, triangular, square, rectangular or diamond-shaped. In case of non-circular holes, it is necessary to consider as the nominal diameter the maximum diameter of the circle inscribed in the polygon. As sound-absorbing material used or sheet sound material which is based on magnesite binder with reinforcing glass or glass, or polyester, or porous sound-absorbing ceramic material with volume density 500÷1,000 kg/m³ and consisting of 100 weight parts of pearlite with grain diameter of 0.1÷8.0 mm, 80÷250 pts.wt of one of sintering materials selected from group comprising ash dust, slag , quartz, lava, stones or clay as main material, 5÷30 pts.wt inorganic binder. After sintering mixture of pearlite particles form communicating holes between contact surfaces so that inner pores are interconnected.

EFFECT: invention allows to improve efficiency of sound absorption and reliability of the structure on the whole.

3 cl, 1 tbl, 1 dwg