SOUND-ABSORBING ELEMENT OF COMBINED TYPE Russian patent published in 2018 - IPC E04B1/84 G10K11/16 

FIELD: acoustics.

SUBSTANCE: invention relates to industrial acoustics and can be used for machine drive noise reduction, lining of manufacturing facilities and in other sound-absorbing structures. Sound-absorbing element of a combined type contains a smooth and perforated surface, between which a layer of sound-absorbing material of complex shape is located. Layer of complex shape is an alternation of solid sections and hollow sections. Hollow sections are formed by prismatic surfaces with cross-sections parallel to plane of drawing, parallelogram shape, which inner surface have toothed or wavy structure. Tops of the teeth face the prismatic surfaces, and the edges of the prismatic surfaces are fixed respectively on the smooth and perforated walls. Hollow cavities formed by prismatic surfaces are filled with a sound absorber, and between a smooth surface and solid sections of a layer of sound-absorbing material of a complex shape, as well as between the perforated surface and solid sections, there are resonant plates with resonant inserts performing the functions of the neck of Helmholtz resonators. In the internal cavities of solid sections, resonance chambers with resonant inserts that perform the functions of the necks of the Helmholtz resonators are located. Resonance chambers by means of resonance inserts are connected to cavities located between smooth and perforated surfaces and solid sections connected to prismatic surfaces of hollow sections, and the internal cavities of hollow sections formed by prismatic surfaces having a form of a parallelogram in the section parallel to the plane of the drawing have resonant chambers with resonant inserts that perform the functions of the necks of the Helmholtz resonators. Resonance chambers are connected by means of resonance inserts to cavities located between the smooth and perforated surfaces and solid sections connected to the prismatic surfaces of the hollow sections.

EFFECT: technical result consists in increasing the efficiency of sound attenuation and the reliability of the structure as a whole.

1 cl, 1 dwg