The tower die crane null folding possible standards structure which has

摘要

PROBLEM TO BE SOLVED: To make a support, which must hold a maximum height or given height in a work site, foldable within minimum external shape dimension or given transport external shape dimension. ;SOLUTION: A support 5 includes a lower support element 6 connected to a rotary chassis 3 of a crane, folding intermediate support element 7, and an upper support element 8 supporting a boom 13 of the crane. A folding/unfolding device of this support 5 includes at least one guide 23 connected to the rotary chassis 3 and the intermediate support element 7, cord 30 connecting the intermediate support element 7 to a king post of a boom 19, jack 27 set up between the rotary chassis 3 and the lower support element 6, and a drive means itself able to include a connecting rod assembly part 34 positioned in a level of the intermediate support element 7. The crane, during transport on a road, is folded.;COPYRIGHT: (C)1999,JPO