Centrifugal fan unit for vehicle air conditioning system

摘要

The fan unit (7) has a screw casing (74), centrifugal fan with several vanes (72) and an electric motor (73). A sound funnel sector (76) to form the induction aperture (75) extends as far as the radially inner end of the fan. A vortex wall is arranged so that the first free cavity is provided between the vortex wall and an inner wall. The second free cavity, connected to the first, is formed between the vortex wall and a wall sector extending to an upper wall surface of the casing.