Patent ID: 6962478

Claim:
A vertical axis windmill, comprising an immovable, hollow circumferential frame having a plurality of peripheral openings through which wind can enter to form a substantially horizontal air flow inside said frame; and rotatable turbine arranged inside said frame and connectable to a generator of electric energy, said turbine having a plurality of vanes each having a working side and a non-working side; and a plurality of gate elements turnably connected with said frame for closing and opening of said openings of said frame by wind flowing substantially in a horizontal plane, said gate elements and said vanes of said turbine being formed so that at one side of said frame the wind opens said gate elements by turning them in a predetermined direction, so that at one side the wind turns said gate elements so as to open corresponding ones of said openings, enters said frame through said corresponding opened openings and acts on said working side of corresponding ones of said vanes so as to rotate said turbine in said predetermined direction, while at the same time at the other side of said frame the wind closes other offset gate elements, wherein each of said vanes being curved in the horizontal plane and curved in a vertical plane so as to be twisted, so that when the wind enters said frame through said open peripheral openings and moves substantially horizontally inside said frame and rotates said vanes, a spent air is diverted upwardly by said twisted vanes and immediately leaves said turbine so as to release a space for a next portion of air provided by the wind.