Patent ID: 6220386
Filing Date: 2001-04-24
Classification: A42B,A61F,H04R

Abstract:
A wind noise reducing, boundary layer flow regulating dam to be worn on a band around a wearer's head so that the dam rests on the temple area, the wearer facing a turbulent headwind; the dam comprisinga base having a width perpendicular to said wind, a length parallel to the wind, an inner surface defined by said length and width and having attachable means for attachment to said band, the base having an outer surface;a matrix comprising said outer surface including an air flow permeable superstructure fastened to said outer surface and having a height normal to the outer surface, said superstructure being flexibly resistant in response to said turbulent headwind;a fibrous aerodynamically porous maze supported and attached to at least part of said matrix to impede but not arrest air flow and to damp out vortices caused by the matrix structure;the combination of the matrix and maze comprising an aerodynamically moved flexible filter having a thickness parallel to said length, said thickness tapering in permeability as a function of height from the outer surface;whereby said filter causes a tortuous path flow impedance gradient to change in direct response to the turbulent variations of the headwind for a dynamically reduced infranoise pattern between the temple area and continuing past the wearer's ear canal.