SOUND-ABSORBING CONICAL PANEL Russian patent published in 2022 - IPC E04B1/82 

FIELD: soundproofing.

SUBSTANCE: invention relates to sound-absorbing panels; it can be used for absorption of noise of cars and aerodynamic devices. A sound-absorbing conical panel contains a thin blind shell, a volumetric cellular shell, and a thin perforated shell. The cellular shell is made in the form of an elastic prismatic cellular block with a trapezoid contour. An increment and coordinates of axes of holes in the perforated shell are determined by ratios:

where s_n is an increment of holes of the perforated shell in a transverse circular row, mm; n is a number of a circular row, when counting from the largest arc of a surface of adjacency of cellular and perforated shells; s is an increment of cells of the cellular block along an elastic wave-shaped tape, mm; t is an increment of cells of the cellular block across the elastic wave-shaped tape, mm; h is a width of the elastic wave-shaped tape and a height of cells, mm; D is the largest diameter of a surface of adjacency of volumetric cellular and blind shells, mm; K is conicity of shells of the sound-absorbing panel; coordinates of axes of holes are determined in a polar coordinated system, a pole of which is set in a vertex of a central angle of a flat sweep of the perforated shell, and a pole line is directed along the axis of symmetry of the sweep; r_n is a polar radius of axes of holes in n^th circular row, mm; m is a number of a hole of the perforated shell, when counting from a pole line in n^th circular row, ϕ_nm is a polar angle of the axis of m^th hole in n^th circular row.

EFFECT: sound absorption and manufacturability of a perforated shell are improved.

2 cl, 8 dwg