Patent ID: 7743880

Claim:
A sound absorbing structure comprising: a housing including a front face, a side face configured perpendicular with respect to at least a part of an edge portion of the front face, and at least one opening; a gas adsorption material placed in an interior space of said housing, which interior space is delimited by the front face and the side face, said gas adsorption material physically adsorbing gas in the interior space; at least one acoustic connection section provided in said opening, said acoustic connection section acoustically connecting the interior space of said housing and an exterior space outside of said housing; and a sealing element provided in the interior space of said housing that completely seals said gas adsorption material within an area of the interior space, said sealing element being capable of preventing gas from entering and leaving the area sealed by said sealing element and also being capable of vibrating so as to allow a sound to be transmitted from the exterior space into said housing, wherein said gas adsorption material expands an acoustic equivalent volume within said housing due to its physical adsorption ability, and forms a Helmholtz resonator due to an acoustic mass of air in said acoustic connection section, an acoustic mass of said sealing element, and the acoustic equivalent volume within said housing.