REVERSIBLE FAN Russian patent published in 1998 - IPC

FIELD: construction of special-purpose and general-purpose fans. SUBSTANCE: blades secured on bush have profile in cross section (section by cylindrical surface) at curvature radius of sections having centers located on different sides from chord connecting the leading and trailing edges. Point of inflection is located beyond midpoint of above-mentioned chord. The invention gives optimized ratios of separate sizes of blade. EFFECT: enhanced efficiency of fan in direct and reversible modes. 2 dwg