Compact two=stage axial flow fan - has exit and entry guide vanes on fixed hub around motor impellers

摘要

The two-stage axial flow fan has a housing (8) containing an electric motor (1) carrying the first impeller (2) on one shaft end (11), and the second impeller (3) on the other shaft end (12). Each impeler has exit guide vanes (4) near the motor between a fixed hub (13) and the housing. The second impeller entry has guide vanes (5), together with the first guide vanes, on the same common guide vane hub (13). The two sets of guide vanes may form a single integral unit. This unit may be designed to produce whirl-free exit flow from the second impeller.