摘要 |
A cooling fan (10) includes a plurality of blades (12) molded about a central hub plate (11) at an annular molded ring (13). A plurality of helical gussets (30) are formed on inlet side (25) of the molded ring (13) at the blade root (15) that are spaced apart to define flow gaps (32) therebetween, and are curved to substantially follow the airflow path through those gaps (32). A like plurality of radial ribs (40) may be formed at the outlet side (26) of the fan (10) that can include an indented stacking surface (41) that engages a contact surface (42) on the inlet side (25) to facilitate stacking of multiple fans. In another aspect, the fan blades (10) are configured to include elliptical or parabolic camber lines (C) that vary along the radial length of the blade so that the blade stacking, or the centers of gravity (CG) of radial blade segments, achieve a predetermined alignment under normal operating loads to minimize bending moments between blade sections.
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