US 4,582,013 A · Self-adjusting wind power machine

Abstract

A machine for economical recovery of wind power employs a self-adjusting mass-balanced aerodynamic blade weathervaning freely around a lengthwise pitching axis forward of its aerodynamic center, and an aerodynamic roller in its leading edge, spun at high RPM by a motor. The roller controls aerodynamic performance to high levels of efficiency at high lift coefficients, employing novel roller/airfoil profiles. For ship propulsion, the self-adjusting blade with roller stopped is like a furled sail, and with the blade held angling to the wind with roller spinning is like a large, efficient, easily controlled sail. On a horizontal axis wind turbine, the self-adjusting blade is continuously held to an efficient angle of attack by centrifugal lift-increasing pitching moments balancing aerodynamic lift-decreasing pitching moments. The blade whirls steadily despite fluctuations of wind speed and direction, reducing stresses, and preventing structural damage or loss of efficiency. Gyroscopic blade teetering moments are neutralized by mass-balance counter-spin, using a single blade with a balancing stub, on a teetering pivot at the mill shaft. A teetering pivot at the top of the mast and horizontal tail surfaces complete an overall dynamic stress relief system. Sensors monitor operating conditions, control roller speed and move centrifugal mass positions for optimum power output.

Claims32

Dependent claims

A wind power machine comprising an aerodynamic blade, said blade comprising an aerodynamic roller supported by said blade pivotally attached lengthwise in the leading edge of said blade, powered motor means spinning said roller, said aerodynamic blade comprising extensive airfoil surface area rigidly supported by stress-carrying structure;

said extensive airfoil surface area comprising extensive outwardly-positioned airfoil surface area lying outboard separated from and beyond the outermost active aerodynamic surface of any said roller, said extensive outwardly-positioned airfoil surface area having an aerodynamic span markedly greater than the maximum diameter of said roller, both of the opposite surfaces of said extensive outwardly-positioned airfoil surface area being exposed to the wind, substantially increasing the lift and reducing the induced drag of said blade, said extensive airfoil surface area comprising substantial rearwardly-positioned airfoil surface area lying rearward of said roller;
said blade comprising stress-carrying structure attaching said outwardly-positioned and said rearwardly-positioned airfoil surface areas rigidly to each other;
a stress-carrying power-generating joint attaching said rearwardly-positioned airfoil surface area structurally to mechanical power transmission means attached to said wind machine, said power-generating joint structurally transmitting the entire wind-generated power output of said blade to said power transmission means, producing power-generating movement of said wind power machine.

A wind power turbine comprising an aerodynamic blade, said blade comprising a tip region extending over more than the outer one-third of the radial length of said blade, all of the external aerodynamically active surface area of said tip region consisting of stationary airfoil surface area, a horizontal mill shaft, and power-generating joint means attaching said blade radially to said mill shaft, said joint means structurally transmitting the entire wind-generated power of said blade to said mill shaft, said joint means comprising a free teetering pivot perpendicular to said horizontal mill shaft, said joint means comprising variable blade angle aerodynamic weathervaning means, said weathervaning means comprising a freely turning weathervaning pivot lying on a weathervaning blade pitching axis lengthwise of said blade generally parallel to the length of said blade and generally perpendicular to said horizontal mill shaft, said weathervaning pivot comprising low friction bearings, said lengthwise blade pitching axis lying forward of the mean effective aerodynamic center of said blade, said blade comprising balancing mass forwardly attached thereto, the total of said balancing mass attached to said blade balancing the weight of said blade around said lengthwise blade pitching axis.

A wind power machine comprising an aerodynamic blade and joint means attaching said blade to said machine, said joint means comprising variable blade angle aerodynamic weathervaning means, said weathervaning means comprising a freely turning weathervaning pivot lying on a blade pitching axis lengthwise of said blade generally parallel to the length of said blade, said lengthwise pitching axis lying forward of the mean effective aerodynamic center of said blade, said blade comprising balancing mass attached to said aerodynamic blade forward of said lengthwise axis balancing the weight of said aerodynamic blade around said lengthwise axis, said wind power machine comprising a horizontal mill shaft, said joint means attaching said blade radially to said mill shaft, said blade comprising variable blade angle centrifugal means, said centrifugal means producing hinge moments around said freely turning weathervaning pivot in the direction increasing the blade angle of said blade;

said variable blade angle aerodynamic weathervaning means producing hinge moments around said freely turning weathervaning pivot in the direction decreasing the blade angle of said blade, the blade angle of said blade being determined by the position of balance between said centrifugal hinge moments and said aerodynamic weathervaning hinge moments acting in opposite directions, said variable blade angle centrifugal means comprising a balanced pair of masses, said balanced pair of masses consisting of two discrete masses of equal weight symmetrically disposed on a straight line perpendicularly intersecting the axis of said freely turning weathervaning pivot, said discrete masses being equally distant from said axis of said freely turning weathervaning pivot on opposite sides thereof;
said balanced pair of masses being attached to said blade on movable mounting means lying along said straight line, said movable mounting means being symmetrical and balanced on opposite sides of said axis of said freely turning weathervaning pivot.

Dependencies are inferred from the claim text.

Self-adjusting wind power machine

Life of this patent

Self-adjusting wind power machine

Life of this patent

Abstract

Claims32