AXIAL-FLOW FAN IMPELLER Russian patent published in 2003 - IPC

FIELD: mechanical engineering; fans. SUBSTANCE: invention relates to impellers of axial-flow fans. Proposed impeller contains blades with shanks provided with thread on end, and hub. Two-step rectangular cutouts are uniformly spaced over periphery of hub. Width of outer step is smaller than width of inner step. Coupling is rigidly secured on walls of outer step and corresponding shank is passed through said coupling. Nut turned onto end of shank is fitted in inner step of each cutout. Washer with outer diameter equal to outer diameter of coupling is installed between shank and coupling. EFFECT: re-distribution of centrifugal load from blades to hub, provision of change of blade setting angle. 4 cl, 3 dwg