NOISE SUPPRESSOR FOR SOCK AND STOCKING MAKING MACHINE Russian patent published in 2017 - IPC F01N1/04 

FIELD: machine engineering.

SUBSTANCE: noise suppressor contains the cylindrical casing, rigidly connected to the end inlet and outlet branch pipes, rigidly connected to the central pipe, having the perforation, the outlet pipe is made in the form of the disc, having at least three holes in the peripheral part, and the central pipe, having the perforations in the form of rectangular gaps of at least three, which is associated with the central solid part of the disc, and the sound-absorbing element is installed between the casing and central pipe in such a way, that the disc holes are connected to the cavity of the sound-absorbing element location, the sound-absorbing element is made of annular type and, in the axial section, it contains the smooth and perforated surface between which the multi-layer sound-absorbing structure, containing two layers is placed: the sound-reflecting layer adjacent to the rigid wall, and the sound-absorbing layer adjacent to the perforated wall. The sound reflecting material layer is made of the complex profile, consisting of the uniformly distributed hollow tetrahedra, that allow to reflect the sound waves falling in all directions, and the perforated wall has the following perforation parameters: the diameter of the holes is 3÷7 mm, the perforation percent is 10÷15%. According to the shape the holes can be made as the holes, having round, triangular, square, rectangular or diamond profile. In case of non-circular holes, the maximum diameter of the circle inscribed in the polygon should be considered as the nominal diameter, and the mineral wool on the basalt basis of the Rockwool type, or the mineral wool of the URSA type, or basalt wool of the P-75 type, or the glass wool with the glass fiber lining, or the foamed polymer, for example, polyethylene or polypropylene is used as the sound-absorbing material. The surface of the fiber absorbers is treated with the porous air-permeable paints (for example, "Acutex T") or covered with the air-permeable fabrics or non-woven materials, for example "Lutrasil".

EFFECT: noise suppression efficiency improvement.

2 cl, 3 dwg