초록 ▼

A movable, prefabricated wall panel having a rigid rectangular frame. A core structure is disposed in the region bounded by the frame, which core structure preferably comprises at least one honeycomb layer. Sheetlike skins are fixedly secured to opposite sides of the frame and extends across the reg

A movable, prefabricated wall panel having a rigid rectangular frame. A core structure is disposed in the region bounded by the frame, which core structure preferably comprises at least one honeycomb layer. Sheetlike skins are fixedly secured to opposite sides of the frame and extends across the region bounded by the frame for confining the honeycomb layer therebetween. A plurality of small openings are formed in either or both of the skins so that they communicate with cells of the honeycomb layer to create Helmholtz sound-absorbing chambers. Each sheetlike skin is covered by a layer of porous fiberglass material for absorbing sound, which layer includes an inner thin mat of high-density fiberglass which is in turn covered by a relatively thick outer layer of low-density fiberglass. This outer layer has a variable density gradient across the thickness thereof, which density gradient progressively increases across the thickness toward the mat.

대표청구항 ▼

In an interior space dividing wall formed from a plurality of portable interior upright space-divider panels which are horizontally connected together in series, said panel having opposed enlarged side surfaces and a sound-absorbing core structure disposed between said side surfaces and extending su

In an interior space dividing wall formed from a plurality of portable interior upright space-divider panels which are horizontally connected together in series, said panel having opposed enlarged side surfaces and a sound-absorbing core structure disposed between said side surfaces and extending substantially coextnesively over the area thereof, said core structure including first means for absorbing sound waves of one frequency and second means for absorbing sound waves of a substantially different frequency, said first means including a plurality of Helmholtz resonators each defined by a small substantially closed chamber disposed interiorly of the wall panel and communicating with the surrounding environment through small opening means which project outwardly from the respective chamber toward one of the side surfaces of the panel, said first means including a thin sheetlike skin having said small opening means extending therethrough, and said second means including a layer of porous-sound-absorbing material overlying said plurality of Helmholtz resonators, said layer being of a porous fiberglass material, the improvement wherein said layer comprises: a thin inner layerlike strata disposed so as to directly overlie said pluraltiy of Helmholtz resonators and said thin skin, said inner strata being of a high-density fiberglass material, and a thick outer layerlike strata disposed directly adjacent and coextensively overlying said inner strata, said outer strata being of a low-density fiberglass material, said outer strata having a density gradient which increases as it extends from its outer surface toward said inner strata, said outer strata consisting of a single integral layer having a variable density which progressively increases across the thickness thereof toward said inner strata, said outer strata having a thickness which is several times greater than the thickness of said inner strata, said inner strata having a density which is several times greater than the average density of said outer strata and which is also greater than the maximum density of said outer strata, and said inner strata having a maximum thickness of about 0.080 inch and a minimum density of about 6 pounds per cubic foot.