Mast raising structure and process for high-capacity mobile lift crane.

摘要

A mobile lift crane (10) includes a rotating bed (20) rotatably connected to a carbody (12); a boom (22) pivotally mounted on a front portion of the rotating bed (20) and a mast (28) mounted at its first end on the rotating bed (20) and having a second end; and at least one hydraulic cylinder (36) pivotally connected at a first end to the rotating bed (20), so as to be able to raise the second end of the mast (28) from a near horizontal position to a position where the mast is used during crane pick, move and set operations. In a preferred embodiment, at least one arm (38) is pivotally connected to the rotating bed (20) and the hydraulic cylinder (36). The arm (38) and cylinder (36) are connected together such that extension and retraction of cylinder (36) causes the second end of the arm (38) to raise and lower. The arm (38) and cylinder (36) support at least one mast-engaging member (37) positioned such that raising the second end of the arm (38) causes the mast-engaging member (37) to push against and raise the mast (28) when the mast (28) is in a set-up state.