High efficiency, low the axial direction border, it is low axial fan null of noise

摘要

PURPOSE: To obtain a high efficiency, low noise, axial flow fan that can be received in an axially limited space. ;CONSTITUTION: Fan blades 16 have a particular geometry that combines high efficiency, low axial profile, and low noise, in an axial flow fan. The fan also comprises a circular outer band 18 that coacts with a surrounding shroud structure to form a labyrinth air seal. The shroud structure comprises two parts that cooperatively define a radially inwardly open groove within which a flange of the fan band is received to form the labyrinth seal.;COPYRIGHT: (C)1994,JPO