Construction Machinery

A construction machinery, comprising:

• a derricking drum disposed at a main frame;
• a gantry that includes a front leg member, a lower spreader laterally disposed at an upper end of the front leg member with a plurality of lower sheaves axially supported at a support shaft, and a rear leg member with an upper end of the rear leg member linked to the support shaft, and is foldably disposed at the main frame;
• and
• an upper spreader that includes a plurality of upper sheaves, with a derricking rope being wound around between the plurality of upper sheaves and the plurality of lower sheaves at the lower spreader, wherein:
• the lower spreader has a width smaller than a width of the front leg member;
• and
• the plurality of lower sheaves at the lower spreader includes at least;
• a first lower sheave at which the derricking rope let out from the derricking drum is first wound;
• a second lower sheave, disposed on a side where a fixed end of the derricking rope at which the derricking rope is fastened is located, at which the derricking rope is wound last;
• and
• a third lower sheave, disposed between the first lower sheave and the second lower sheave or at a position adjacent to either the first lower sheave or the second lower sheave, at which the derricking rope, running from an upper sheave among the plurality of upper sheaves at the upper spreader is wound so as to run toward another upper sheave at the upper spreader.