WINDMILL Russian patent published in 1997 - IPC

FIELD: wind-electric power engineering. SUBSTANCE: windmill has shaft kinematically linked with electric generator, adjustable blades with fly mounted on turning bushes which are installed on shaft, blade operating mechanism kinematically linked with turning bushes, and blade control system coupled with its operating mechanism; each blade is set in windmill rotation plane at certain angle to direction of rotation; this angle is formed by longitudinal axes of blade and bush and amounts to 0.5-2.0 deg; blades are curved in section relative to curvature axis aligned with longitudinal axis of blade displaced from section chord towards greater curvature of blade profile; front edge of blade is spaced from longitudinal axis of blade at 0.2-0.25 of chord of respective blade sections. Novelty is that blade fly end is beveled at 0.5-2.0 deg relative to plane perpendicular to longitudinal axis of bush and also that curvature axis displacement may be constant lengthwise of blade for all sections or may be variable lengthwise of blade, and may be set both constant in absolute quantities and constant relative to present thickness of blade profile. Windmill blade may be also tilted due to bush end bevel relative to plane perpendicular to blade radius axis. EFFECT: enlarged speed range of operating wind currents, primarily low-speed ones. 7 cl, 5 dwg, 1 tbl