SINGLE KOCHETOV'S ACOUSTIC ABSORBER OF COMBINED TYPE Russian patent published in 2015 - IPC E04B1/84 

FIELD: machine building.

SUBSTANCE: in single acoustic absorber of combined type containing active and reactive acoustic absorbers located on rigid framework, the framework is made out of two parts. The bottom part is made in form of a rigid, hollow structure of cylindrical-and-cone shape, and top part is made in form of rigid perforated cylindrical shell with perforated cover and solid base. Cavity of the cylindrical shell is filled with sound absorbing material, and connection between top and bottom parts is made by means of the resilient damping element ensuring damping of HF oscillations. On the perforated cover of the perforated cylindrical shell the pin connected element is installed to secure the framework to the required object. Around the perforated cylindrical shell there is spiral sound absorbing element. In the framework bottom part the hollow cylindrical part of the framework is made as resonance Helmholtz muffler and contains mouths of different diameters located on the cover and base of the hollow cylinder, and on its side surface, at that the hollow cone and cylindrical parts are connected by the mouth.

EFFECT: improved efficiency of noise suppression at high frequencies.

2 cl, 1 dwg