| 摘要 |
A crane or the like (e.g. an access platform or excavator), having a boom wherein the boom is lifted or lowered by one or more hydraulic rams or the like, the or each ram acting on a cradle on which the boom rests and in which it is free to move, the cradle being linked to the platform or the base of the crane or the like, at a point between the foot of the ram(s) and the foot of the boom or at the foot of the boom. This arrangement has the advantage that the boom stresses during lifting are evened out, and expensive accurate machinery of the boom pivot holes are avoided.
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