SINGLE-PIECE SOUND ABSORBER Russian patent published in 2018 - IPC E04B1/84 G10K11/16 

FIELD: acoustics.

SUBSTANCE: invention relates to means of reducing noise in industrial and transport facilities. Technical result is achieved by the fact that the unit sound absorber comprises a rigid perforated frame, inside of which a sound-absorbing material is placed, frame is made of a lower part of a conical shape with a lid and a top part of a cylindrical shape which is fixed to the lid of the lower part of the perforated cage by means of a vibration damping pad that allows to damp high-frequency vibrations, while to the upper part of the cylindrical perforated frame an element is hinged, with the help of which the frame is attached to the required object, for example, the ceiling of the production room, and the cavities of the lower and upper parts of the perforated frame are filled with sound-absorbing materials of various densities, and at least one is located around the upper part of the cylindrical shape of the perforated frame, screw absorber element of the unit absorber, made in the form of a cylindrical helical spring of a dense, non-combustible sound-absorbing material, screw sound-absorbing element of the unit absorber is made in the form of a hollow screw sound-absorbing element formed by the outer and inner helical surfaces forming the cavity, while the space formed by the outer and inner helical surfaces is filled with a sound-absorbing material, while the cavity of the screw sound-absorbing element, formed by its external and internal screw surfaces, is filled with sound absorbing material from mineral wool on a basalt basis of the "Rockwool" type, or mineral wool of the URSA type, or P-75 type basalt wool, or glass wool with a glass wool lining, the sound-absorbing material over its entire surface is lined with an acoustically transparent material, for example, glass fiber of the type EZ-100 or a polymer "poviden" and the outer and inner screw surfaces of the screw sound-absorbing element are made of a material based on aluminum-containing alloys, followed by filling them with titanium hydride or air with a density within 0.5…0.9 kg/m³ with the following strength properties: compressive strength within 5…10 MPa, bending strength within 10…20 MPa, for example foam aluminum, outer screw surface of the screw sound-absorbing member being perforated, and as a sound-absorbing material of the lower part of the conical frame, a porous sound-absorbing ceramic material having a bulk density of 500÷1,000 kg/m³ and consisting of 100 parts by weight of perlite with a particle diameter of 0.5÷2.0 mm, 100÷200 parts by weight of one or more sintering materials and 10÷20 parts by weight of binding materials, with the gasket made of a plastic type "Agate" or mastic VD-17.

EFFECT: technical result is an increase in the efficiency of noise reduction at low and medium frequencies.

1 cl, 2 dwg