Method of lifting nacelle, nacelle lifting mechanism, tower, and wind turbine generator

A method of lifting a nacelle installed on a tower, comprising:

• attaching a tapered bushing mechanism to a through-hole provided for a member of said tower;
• attaching a push-up bolt to said tapered bushing mechanism;
• and
• raising said push-up bolt while pushing said push-up bolt against a first member provided for said nacelle,
• wherein said tapered bushing mechanism comprises a tapered bushing inner cylinder and a tapered bushing outer cylinder,
• wherein said tapered bushing inner cylinder comprises a first taper section whose outer diameter becomes larger toward an end of said tapered bushing inner cylinder and a first screw thread formed on an inner surface of said tapered bushing inner cylinder,
• wherein said tapered bushing outer cylinder comprises a second taper section whose inner diameter becomes smaller toward an end of said tapered bushing outer cylinder,
• wherein said attaching said tapered bushing mechanism to said through-hole comprises:
• inserting said tapered bushing mechanism in said through-hole such that the end of said tapered bushing inner cylinder is positioned on an up side, the end of said tapered bushing outer cylinder is positioned on a down side, an outer circumferential surface of said first taper section and an inner surface of said second taper section contact, and an outer circumferential surface of said tapered bushing outer cylinder contacts said through-hole;
• and
• pulling down said tapered bushing inner cylinder in a state that said tapered bushing mechanism has been inserted in said through-hole, and
• wherein said raising said push-up bolt comprises turning said push-up bolt in a state that said push-up bolt has been engaged with said first screw thread.