Heavy duty crane

A heavy duty self-propelled mobile crane for use at a working site having a generally horizontal support surface;

• said crane including a chassis with ground engaging transport means, auxiliary frame means connected to said chassis for rotation about a vertical axis and having diametrically opposed end portions, article handling means primarily supported by one end of said frame and adapted to have a heavy article connected thereto for movement to a different location, counterweight means carried by the other end of the frame, and rotation supporting means operatively connected to the end portions of said frame for supporting said frame for rotation about said vertical axis when in a working position;
• the improvement which comprises means connecting said frame to said chassis for vertical movement relative thereto between said working position and a transport position, and power means operatively connected to said frame for changing the elevation of said frame and the components that are mounted for vertical movement therewith between elevations wherein the lowermost of said vertically movable components is either at said working position or at a position spaced above the ground a sufficient distance for providing adequate road clearance.

A heavy duty crane which includes a self propelled mobile lower works and means defining mobile crane components connected to said lower works for transportation therewith;

• said crane components including auxiliary frame means supported by said lower works for rotation about a vertical axis, article handling means primarily supported by one end of said frame means and adapted to have a heavy article attached thereto, counterweight means supported by the other end of said frame means, and roller means supported by said frame means at both ends thereof and adapted to roll upon means defining a hard rigid annular surface supported by the ground during operation of the crane at a construction site;
• the improvement which comprises power operated means for raising said mobile components to a transport position spaced a sufficient distance above the ground to provide adequate road clearance and for lowering said auxiliary frame and components attached thereto into a working position with said rollers on said annular surface for rotary movement about said vertical axis during an article handling operation.

In combination with a crane having a chassis with ground engaging propelling members and having a boom supporting frame rotatable about a vertical axis with respect to said chassis, a bed mounted on the ground to receive said frame in supporting engagement, the improvement comprising roller means interposed between said frame and said bed, and jacks connected between the chassis and the frame to lower and raise the frame with respect to said chassis and bed selectively for support of the rotatable frame by said roller means on the bed when the frame is lowered and for lifting the frame from the bed to clear the bed when the crane is moved onto or from the bed, said ground engaging propelling members remaining supported on said bed while the frame is being raised and lowered.

In combination with a crane having a chassis with ground engaging propelling members and having a boom supporting frame rotatable with respect to said chassis, the improvement comprising a bed mounted on the ground scaleable by said propelling members, means to lower and raise the frame with respect to said bed selectively for support of the rotatable frame by the bed and for lifting the frame to clear the bed when the crane is moved from the bed, and rollers between the bed and the frame for support through the rollers of the frame by the bed and for rotation through the rollers of the frame on the bed.

In combination with a crane having ground engaging propelling members and having a boom-supporting frame rotatable with respect to said propelling members, said frame having rollers depending therefrom, the improvement comprising a bed mounted on the ground scaleable by said propelling members, and means to lower and raise the frame with respect to said propelling members selectively to engage said rollers with the bed for support and rotation of the frame on the bed and to disengage said rollers from said bed for movement of the crane from the bed.

In combination with a crane having a chassis with ground engaging propelling members and having a boom-supporting frame, said crane having means to rotate said frame about a vertical axis through said chassis, and said frame having rollers depending therefrom, the improvement comprising a bed mounted on the ground scaleable by said propelling members, and means on the chassis to lower and raise the frame with respect to said chassis selectively to engage said rollers with the bed for support and rotation of the frame on the bed and to disengage said rollers from the bed.

In combination with a crane having a lower works with ground engaging propelling members and having an upper works for powered rotation about a vertical axis on the lower works, said crane having a boom-supporting frame with rollers thereon and having means to rotate said frame with said upper works about said vertical axis, the improvement comprising a bed mounted on the ground and including a ring, said bed and ring scaleable by the propelling members of the crane for movement of the crane inside the ring to a position where said vertical axis is centered with respect to the ring, and means on the lower works to lower and raise the frame relative to the lower works and to the ring but with the ground engaging propelling members remaining supported on the bed.