SOUNDPROOFING ENCLOSURE Russian patent published in 2018 - IPC E04B1/82 

FIELD: acoustics.

SUBSTANCE: invention relates to protective devices connected with safety precautions, in particular to means for noise reducing of machinery and equipment. Sound-insulating enclosure contains casing mounted on a vibration isolation support, which is made in the form of box, between which walls the noise-absorbing element is placed. Casing freely rests against the shelves, placed between the walls along the support perimeter, and on the shelves shock absorbers are fixed made of elastic material, for example, soft rubber. Between the shelves, ventilation ducts are made, vibration isolating support is mounted on the solid elastic gasket and fixed to the foundation, on which the protected object is installed, using bolts and rubber-metal washers. Casing frame is made of noise-absorbing elements inscribed in its outline. At that, the noise-absorbing element is made in the form of five layers, two of which, adjacent to the walls, are sound-absorbing layers from the different density materials, and three central layers are combined. Axial layer is made sound absorbing, and two symmetrical adjoining layers are made from the complex profiled sound reflecting material composed of evenly distributed hollow tetrahedrons, allowing to reflect the falling in all directions sound waves. Each of perforated walls has following perforation parameters: holes diameter – 3÷7 mm, perforation percentage 10÷15%, wherein by the form holes can be made in the form of round, triangular, square, rectangular or diamond-shaped profile holes. In case of non-circular holes, it is necessary to consider as nominal diameter maximum diameter of circle inscribed in polygon. Sound-absorbing material used is in the form of Rockwool mineral wool boards on a basalt base or URSA mineral wool or P-75 basalt wool or glass wool lined with glass felt. Over its entire surface the sound-absorbing element is lined with the acoustically transparent material or as the sound-absorbing material a porous sound-absorbing material is used. Fibrous sound absorbers surface is treated with special air permeable porous paints, or non-woven materials. As the sound-reflecting material, the aluminum-containing alloys based material is used, with their subsequent filling with titanium hydride or air with density within 0.5…0.9 kg/m³ with the following strength properties: compression strength within 5…10 MPa, bending strength within 10…20 MPa or the “Noise-stopper” type glass staple fiber based soundproofing plates with the material density of 60÷80 kg/m³.

EFFECT: technical result consists in increasing the efficiency of noise attenuation.

1 cl, 6 dwg