CPC B66C 23/76 (2013.01) | 20 Claims |
1. A mobile lift crane comprising:
a carbody including moveable ground engaging members;
a rotating bed rotatably connected to the carbody such that the rotating bed can swing with respect to the ground engaging members;
a boom pivotally mounted on a front portion of the rotating bed;
a mast mounted on the rotating bed at a first end of the mast;
a backhitch coupled to the mast and the rotating bed;
a linear actuation device pivotally connected to the rotating bed;
a moveable counterweight unit coupled to the linear actuation device;
a tension member coupled to the mast and to one of the linear actuation device and the moveable counterweight unit; and,
wherein the linear actuation device is operable to move the moveable counterweight unit toward and away from a front portion of the rotating bed during a pick, move, and set operation by extending the linear actuation device.
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