US Patent 7325882 Rock cutting machine

A rock cutting machine including a boom rotatably mounted at a proximal end to a chassis adapted to be placed adjacent a rock face to be cut. The boom extends from the chassis to a distal end adjacent the rock face. A longitudinal boom axis extends between the proximal and the distal ends of the boom and a cutting device is pivotally mounted about a pivot axis adjacent the distal end of the boom. The pivot axis enables wrist movement about the pivot axis by a drive mechanism and is offset from the longitudinal axis of the cutting device.