ANTI-NOISE HEAD PHONE (VERSIONS) Russian patent published in 2007 - IPC A61F11/06 A42B1/06 A42B3/16 G01K11/00 

FIELD: aids for protection against noise.

SUBSTANCE: anti-noise head phone can be used as aid for protection ears of human working under conditions of high acoustic noises and as aid being component of protection helmets etc. Anti-noise head phone has internal case provided with opening being size-adjusted and external case. Both cases are connected by connecting link. Device also has sealing shaft, onto different of which shaft the internal and external cases are connected correspondingly. Space between cases s filled with sound-absorbing facing. As facing the plates made of mineral cotton, like "Rockwool", on basalt basis can be used, or mineral cotton "URSA", either basalt cotton P-75, or glass cotton provided with facing made of glass felt, or foamed polymer like polyethylene or polypropylene. Sound-absorbing element has its total surface faced by acoustic transparent material, for example, with glass tissue of EZ-100 type or "Povyden" polymer for the first version. Plates on base of aluminum-containing alloys are used filled with titanium hydride or with air at density within 0,5-0,9 kg/m³ to have the following properties: compression strength is within 5-10 MPa, bent strength is within 10-20 MPa for second version. For the third version, members made of solid porous noise-absorbing material are used as noise-absorbing facing, which is namely foamed aluminum or metal ceramics, either metal plastics, or shell rocks with degree of porosity being within 30-45% range. According to fourth version, members with layer-by-layer reeling of porous threads, reeled upon acoustic transparent frame, like wire frame, are used. According to fifth version, crunches of solid vibration damping materials are used, for example, elastomer, polyurethane, or "Agat", "Antivibrit", "Shwim" type flexible PVC. Size of fractions of crunch is 0,3-2,5 mm.

EFFECT: higher noise protection.

5 cl, 3 dwg