Reduced noise room ventilator - has chamber with entry opening larger than discharge openings at ends of distributor ducts

摘要

The casing for a room ventilator is designed for noise reduction. A chamber (5) from which air is discharged sideways through one or two ducts (6) has an entry opening (3) which is larger than the discharge opening (4) at the far end of the duct. The entry chamber is rectangular, so that there is an abrupt surface (19,20) between the entry and discharge (22,23) openings of the chamber. The entry opening can have a flange (12) around it, projecting inwards and an axial fan (13) can be mounted in this opening The two discharge openings at the outer ends are at right angles to the ducts. The ducts can be formed by layers (24) of sound absorbing material supported inside a casing (16). PS.