MULTILAYER ACOUSTIC PANEL Russian patent published in 2009 - IPC E04B1/74 

FIELD: construction.

SUBSTANCE: multilayer acoustic panel contains a frame with arranged inside its internal cavity noise-attenuating insert. The frame is made as a parallelepiped, formed by the front and back walls of the panel, each whereof is flat-topped. On the front wall there is a slatted perforation. Walls of the panel are fixed against each other with vibration damping covers. Perforation coefficient of the front wall is accepted equal to or more than 0.25. Noise-attenuating insert is made integral or consisting of, at least, two layers of noise-attenuating panels, each whereof is perforated at an angle of α=50°-80° against its surface. Axes of perforation openings of adjoining panels are arranged at a 1.5 α angle against each other. Front and back walls of the frame of noise-attenuating elements are made of stainless steel or galvanised sheet of 0.7 mm thick with polymeric protective-decorative coating of 50 mcm or 25 mcm thick, or of aluminium sheet of 1.0 mm thick and with the coating of 25 mcm thick. Ration of the height h of the frame to its width is within the optimal values ratio: h/b=1.0-2.0. Ratio of the value of the frame thickness s' in full assembly to its width b is within the optimal values ratio; s'/b-0.1-0.15. Ratio of the value of the thickness s of noise-attenuating material to the thickness of the fame in full assembly s' is within the optimal values ratio: s/s'=0.4-1.0.

EFFECT: improved noise-attenuation characteristics of the panel.

6 cl, 2 dwg