Patent ID: 6320273
Filing Date: 2001-11-20
Classification: F03D,F05B,Y02E

Abstract:
A large vertical-axis variable-pitch wind turbine, comprising a tower structure, a vertical turbine shaft supported by said tower structure, a hub structure affixed on said turbine shaft and carrying radially disposed horizontal struts, vertical blades pivotally attached to said horizontal struts, and a tail structure with a vane and a system for cyclical change of blade pitch-angle at each turbine turn, wherein the improvement comprises:a support means for said tail structure which support means is mounted on said hub structure;a tail-axle held in bearings by said support means and positioned above of and co-axial with said vertical turbine shaft, and carrying said tail structure;a steering mechanism in a case affixed to lower end portion of said tail-axle in the space above said hub structure, for driving a steering pivot to various positions differently eccentric to said turbine shaft along a line generally parallel with the wind direction;said steering pivot carrying a rotatably mounted hub for fastening a plurality of connecting means; andsaid connecting means between said steering pivot and each turbine blade, for blade pitch-angle control;whereby magnitude of cyclical variation of blade pitch-angle is dependent on eccentricity of said steering pivot position, controled by said steering mechanism, sothat it varies at any significant change of actual wind speed, to hold the wind-to-blade incidence angle to achieve highest possible efficiency.