WIND WHEEL BLADE MADE FROM COMPOSITE MATERIAL AND METHOD OF ITS MANUFACTURE Russian patent published in 2003 - IPC

FIELD: windmills; manufacture of blades, fans and wings from composite materials for flying vehicles. SUBSTANCE: hollow wind wheel blade includes shank part and filler made from light material of porous structure; arranged in shank part are liners with insert made from composite material and laid between them; inner cavity of blade is filled with mixture at ratio of 20- 60 g of binder per 1-1.1 l of light porous material whose strength characteristics change along length of blade. Method of manufacture of wind wheel includes applying layers of glass fabric impregnated with binder followed by stand, mechanical treatment, assembly of blades, filling of inner cavity with filler; prior to filling the cavity with filler, filler is mixed with binder at ratio of 20-60 g of binder per 1-1.1 l of filler at temperature not higher than 25 C during time required for complete wetting of loose material followed by holding the mixture at temperature of 80 C till complete hardening. Strength characteristics of blades are changed with distance from shank part. Proposed method reduces cost by 3-7 times, cycles by 3-4 times and mass by 1.5-3 times at enhanced rigidity due to enhanced strength of shank part and reproduction of weight and overall dimension parameters increased by 1.5-2 times. EFFECT: increased service life. 5 cl, 3 dwg