| 摘要 |
A device for reduction of sound transmission through a structure unit (11), e.g. a wall, door, window or the like. The structure unit consists of at least two pane-shaped parts (12,13) spaced apart a small distance from each other, one of which parts is air-proof. The space (14) between the pane-shaped parts (12,13) is subdivided in several fluidum slots (14a,14b) by means of a longitudinally extending pane- or film-shaped element (15). In the element (15) and/or in limiting members (19) adjoining thereto are made through-openings (10), thus that the sound pressure (P) in the slots (14) is equalized. The rigidity (k) and the surface weight (m) of the element are chosen thus in relation to size and total area of the openings (10) that the oscillation velocity of the element, when this is oscillated, is offset in phase relative to the sound pressure, causing pressure differences in the slots (14), whereby the area of the openings (10) realtive to the surface of the element (15) is 0,1 < w . m . s < 10 wherein: w = the dimensioning angular frequency (2 pi f) and <MATH> e |
