Patent attributes
A crane performs a self-assembling/disassembling operation using a hoisting winch, a hoisting rope, and a hanging hook, and includes a sheave device for guiding the hoisting rope on an upper portion of a lower boom. The sheave device includes a first sheave on a rear side of the lower boom and second and third sheaves on a front side of the lower boom. The second and third sheaves are arranged next to each other in the left-right direction, and the rope end is attached to the lower boom at a position near the top end of the lower boom. Accordingly, a lifting height in the self-assembling/disassembling operation is increased and the rope end can be attached/detached easily and safely from the front side of the lower boom when the lower boom is laid on the ground.
