Abstract: An excavator can be moved in a step-like manner employing its boom and stepping feet or it can be arranged for conventional driven wheeled movement. The excavator includes a supporting frame with outwardly extending supporting arms on which first wheels and/or stepping feet can be mounted. A superstructure is positioned on the supporting frame and the boom is articulated to the superstructure. A second wheel is supported on the superstructure and can be moved in the vertical direction between an active position resting on the ground on which the excavator is supported and an inactive position spaced upwardly from the ground. With two first wheels on one side of the supporting frame and the second wheel in the active position on the opposite side, conventional three-wheel driven movement can be achieved with the second wheel effecting the steering of the excavator.

Abstract: Apparatus for cutting tree parts adapted to be operatively mounted on vehicles including a base structure configured to define a concave cutting recess for receiving therein the tree part to be cut with at least one pivotable holding arm adapted to grip a tree part engaged within the cutting recess and with a cutter plate having a generally planar configuration and defining a cutting edge adapted to be moved through the cutting recess to cut the tree part held therein. The cutter plate is pivotally mounted on the base structure for movement through a cutting operation by pivotal motion thereof and a slotted guide opening is defined in the base structure between the cutter plate pivot and the cutting recess through which the cutter plate moves during a cutting operation. The cutter plate thereby is capable of projecting freely through the slotted guide opening into the cutting recess over the sector of the cutter plate adjacent the cutting edge thereof by passage of the cutting edge through the cutting recess.