Abstract: A Darrieus-type vertical axis wind turbine with tensioned blades is disclosed, along with various mechanisms for tensioning the blades. When the wind turbine is stationary in high wind conditions, the blades are tensioned to resist buckling. When the wind turbine is coming up to operational speed, or slowing down to a stop, the blades may also be tensioned to change the dynamic resonance characteristics of the rotor to avoid operation at resonant frequencies.

Abstract: A wind turbine for mounting on an existing industrial chimney (1), tower or the like, includes two vertically aligned blades (3) mounted on rotor arms (2) for rotation about the longitudinal axis of the chimney, tower or the like. The rotor arms are supported from an annular structure (8) secured to the outer circumference of the chimney, tower or the like and include at their radially innermost ends a rotor arm ring (11) which cooperates with the annular support structure to enable the rotor arms and blades to rotate about the chimney, tower or the like under the influence of wind pressure. Drive ring (16) carried by one or each rotor arm (2) are connectable to gearing of one or more power generators (9) positioned within or extended to the chimney, tower or the like.

Abstract: A vertical-axis wind turbine includes two or more elongated blades connected to a rotor tower. The tower defines an axis of rotation and is linked, preferably via a gearbox or other torque-converting arrangement, to the shaft of a generator. Each blade is "twisted" so that its lower attachment point is displaced angularly relative to its upper attachment point. In a preferred embodiment, the radial distance of each blade from the axis of rotation varies between upper and lower attachment points such that the blade lies approximately along a "troposkein", which is the shape assumed by a string clamped at each end and spun about an axis passing through the ends of the string. The ratio between blade chord length and blade thickness is preferably constant over the length of each blade, with the middle of each blade approximately 80% as thick as its ends. The cross-section of the blades may be teardrop-shaped, shaped as an airfoil, rectangular, or curved in some other way.

Abstract: A Darrieus-type vertical axis wind turbine is disclosed which includes a vertically extending hollow rotor shaft mounted on a support structure with two, three, or four rotor blades of troposkein configuration on the rotor shaft for rotating the shaft in response to wind energy and thereby drive a generator to produce electrical power. The turbine includes an erection hinge and gin pole which permits the turbine to be cable hoisted using a simple winch mounted at or near ground level. The erection hinge and pole also permits the turbine to be completely assembled near ground level. The turbine includes two sets of guy cables. The upper set holds the upper bearing assembly and the upper rotor shaft portion in a fixed vertical position. The lower cable set holds the lower rotor shaft portion and the support structure also in a fixed vertical position. A flexible coupling is used to connect the low speed shaft of the generator speed reducer to the rotor shaft.

Abstract: A wind energy converter with a rotor having a vertical swivelling axis has n each rotor arm a vertical vane that is supported so as to be able to pivot about an approximately vertical pivotting axis on the leading edge of the vane. A balance weight is installed in a vane nose section that is located ahead of the leading edge of the vane. The overall center of gravity of the mass of the body consisting of the vane and the balance weight is located ahead of the swivelling axis of the vane. The vane is made with an assymetrical airfoil section. The vane adjusts to the particular optimal angle of attack in the course of each rotation of the rotor. The wind energy converter has a high degree of efficiency at low and medium relative velocity values, and is self-starting.

Abstract: The invention relates to a wind-driven generating plant for utilizing the energy contained in land and sea winds with at least one blade rotatable about a rotation axis, which is arranged in oblique-angled manner to the horizontal and is optionally connected to a pylon arranged so as to rotate coaxially to the rotation axis of the blade or blades, whereby the hub thereof used for receiving the blade base with associated energy transmission means is connected to a supporting member. Each rotor blade is at an angle .beta. of approximately 40.degree. to 80.degree. to the rotation axis of the rotor, which is oriented at an angle .alpha. of approximately 30.degree. to 70.degree. to the horizontal. The supporting member is arranged on a frame so as to rotate about a vertical axis or at an axis arranged in oblique-angled manner to the vertical.

Abstract: The present invention is directed to a venturi rotor apparatus for producing power from the rotation thereof. The apparatus comprises a support and a central core having a spherical triangular cross-section mounted on the support for rotation about a central axis through the core. A plurality of support arms, fixed to the central core, extend radially outward therefrom at the verticies of the spherical triangle. At least three airfoils are fixed to a radially extended portion of the support arms such that a gap is formed between the surface of the central core and the surface of the airfoils, with the airfoils being aligned on an axis parallel to the axis of the central core. Fluid flow, such as air flow, having at least a component in the direction perpendicular to the axis of the central core flows through the gap producing a venturi effect for enhancing the movement of the airfoils about the axis of the central core.

Abstract: Curved airfoils are mounted on members attached to a vertical shaft. The ends of the airfoils point outward from the shaft. The members are attached to the upper and lower sections of the airfoils and converge as they approach the shaft. This minimizes the shaft length above the turbines upper most bearing and provides a balanced condition that distributes forces in such a manner which reduces airfoil stress.

Abstract: A wind turbine comprises a vertical, rotatable shaft and at least one arm, preferably two or more arms, extending radially outwardly from the shaft and rigidly connected thereto at one end. An aerofoil-shaped blade is connected to the other end of each arm and has a normal operating position in which the blade chord line at the point where the blade connects to the arm is generally normal to a longitudinal axis of the respective arm. The leading edge of the blade is disposed at a fixed acute angle relative to the vertical at all rotational speeds of the blade about the axis of the shaft. The arms preferably also have an aerofoil-shape. An overspeed control mechanism is provided to prevent the blade and arm from rotating beyond a predetermined speed limit about the shaft. The control mechanism includes a hinge mount pivotally connecting the blade to its respective arm.