Patent ID: 7530785

Claim:
Apparatus for use in a wind turbine having at least a first blade with a longitudinal axis, wherein said blade rotates about a rotation axis, said first blade being movable with a flap motion about a flap axis which is substantially perpendicular to said rotation axis through a range of flap angles, said first blade being pivotable about said longitudinal axis through a range of pitch angles to provide a pitch motion, the apparatus comprising: an effective coupling between said flap motion and said pitch motion such that said flap motion is accompanied by a force tending to cause pitch motion, with the ratio of angular degrees of change in flap angle, starting at a given flap angle, to angular degrees of resultant pitch angle change defining a coupling ratio at said given flap angle; and, a link having a distal end and a proximal end, said distal end coupled, at a point non-collinear with said longitudinal axis, such that movement of said distal end provides pitch motion, said proximal end being pivotable about at least a first pivot axis; said first pivot axis being movable with respect to said flap axis.