Patent ID: 7267530

Claim:
A windmill apparatus comprising: windmill means mounted to a windmill shaft to rotate said shaft in response to air flow through said windmill means; the windmill means comprising multiple sets of three windmill blades, said blades in a set being attached to one another and mounted to a single hub, wherein the blades of each set of windmill blades are predominantly flat, of uniform cross-section, have a central portion ending in tips, and have a lip at one tip; the blades in a set further comprise a first blade that has a cord length “X” measured from tip to tip on a line parallel to the plane of the central portion; a second blade somewhat smaller in overall length than the first blade; and a third blade somewhat smaller in overall length than the second blade; the blades are positioned with respect to one another such that the center of the central portion of the first blade is spaced approximately 50% of the blade cord length “X” from the center to the center of the central portion of the second blade; and the second blade is positioned with respect to the third blade such that the center of the central portion of the second blade is spaced approximately 50% of the second blade's cord length from the center to the center of the central portion of the third blade; the second blade is positioned with respect to the first blade with a 15 degree increased angle of attack greater than the angle of attack of the first blade to the direction of wind through the windmill; a tip of the second blade is positioned approximately 1/10th of the cord length “X” back from a tip on the first blade on a line taken perpendicular to the line parallel to the cord length “X”; said line passing through said tip on said first blade; the cord length of the second blade is approximately 70% of “X” and the third blade is dimensioned and positioned with respect to the second blade, with the same ratios as given with respect to the first and second blades.