Movable sheave assembly for a crane

摘要

A convertible crane with a movable sheave assembly which is operable in two distinct positions. In the first position, the sheave is adjacent the body of a crane to enable it to operate in relatively restricted space without interference from obstacles adjacent the rear end of the base. In the second position, the sheave extends away from the body of a crane where it may be attached to an auxiliary counterweight to enable a crane to lift larger loads. The movable sheave assembly enables a crane to be easily and rapidly converted between normal and enhanced lifting modes.