Patent ID: 9494133
Filing Date: 2016-11-15
CPC Classification: B66C,F03D,F05B,Y02E,Y02P,Y10T

Claim Text:
1. A method of lowering a blade from a wind turbine comprising the steps of: removing a blade from a wind turbine supported upon a tower; affixing a lifting yoke to the root end of said blade; attaching a hoisting cable to said lifting yoke and providing support for said hoisting cable from a position above said lifting yoke; attaching a tip end shoe to a portion of said blade between the tip and the midpoint of said blade, said tip end shoe including a crane hook receiving component; securing said tip end shoe in position along said blade with a cord attached to said tip end shoe and extending to and attached in proximity to said root end; threading a left tag line through a first tag line support structure attached to said tip end shoe and a second tag line support structure attached to said cord in proximity to said root end such that said left tag line is capable of exerting a force at both said tip and said root end of said blade; threading a right tag line through the first tag line support structure and the second tag line support structure such that said right tag line is capable of exerting a force at both said tip and said root end of said blade; attaching a crane cable from a crane to said crane hook receiving component; attaching said hoisting cable to a winch such that operation of the winch in a first direction releases hoisting cable toward said lifting yoke and operation of the winch in a second direction draws hoisting cable from the direction of said lifting yoke; operating said winch in said first direction whereby said lifting yoke and said blade are lowered toward the ground; manipulating said tag lines as necessary to prevent said blade from striking said tower; tightening said crane cable from a point above said tip end shoe to impart a rotation of said blade to a substantially horizontal position; lowering said blade using said hoisting cable and said crane cable to support the weight of said blade while manipulating said tag lines to orient said blade to a desired position for emplacement on the ground or on a receiving platform.