| 摘要 |
<p>Device for absorption of airborne sound, comprising a rigid, air permeable and self-supporting carrying layer having a flexible, air impermeable membrane applied thereto. The device is characterized in that the carrying layer has an air flow resistance of less than 10,000 Pas/m, that the layer has a thickness of 1-60 mm, preferably 5-20 mm, and that at least one surface of the layer is provided with a relief pattern. The device is further characterized in that a flexible membrane having a surface weight of less than 2 kg/m2 is firmly attached to the carrying layer by gluing or the like. The membrane is resting on the upper parts of the relief pattern, whereby an air gap is obtained between the membrane and the lower parts of the relief pattern.</p> |
