| 摘要 |
An air transfer arrangement 10 arranged to ventilate a room comprises an enclosure 12 defining a passage with an inlet and an outlet, and a plurality of sound absorbing structures 20 extend across the passage. At least three structures may be present and offset relative to each other longitudinally or transversely between the inlet and outlet. The structures comprise first (32, fig 6) and second (36) sound absorbing materials having different sound absorbing properties. The first material may be granular, rubber, chip form or wood and located centrally within the structure. The second material may be mineral wool, wool or cotton wool. The structures may be oval to reduce air resistance. The enclosure may be made from sound absorbing material comprising acoustic board. A grille (54, 62, fig 7) is located at the inlet and/or outlet and comprises a plurality of bars across the passage. A modulating damper (48) comprising a plurality of dampers (50) extends across the passage. An intumescent damper (56) formed as a grille (58) may be provided. A fan (44) in a housing mounted to an end of the enclosure may urge air through the passage. The enclosure may be located above a ceiling. |
