Abstract: A caterpillar-type travelling mechanism for vehicles provided with a self-propelled drive, particularly hydraulic dredges, with a drive sprocket wheel, a guide wheel for the guidance of the caterpillar chain and chain links connected with one another by bolts. Cam-shaped teeth are arranged on the drive sprocket wheel in its longitudinal center plane, the teeth being provided on the sides which point toward one another with planar surfaces. The drive sprocket wheel is provided on its outer periphery with two running rims for the chain links, the rims being arranged on both sides of the teeth. The cam-like teeth are arranged on the periphery of a wheel flange, the latter on both sides being provided with inclined surfaces for guiding the chain links. The travelling mechanism plates of the chain links, which plates are formed as double-stud plates, are made of one piece with a two-sided cam arranged centrally in the chain link.

Abstract: A hydraulically controlled and driven dredge, in which the pumps for delivering the driving fluid for the bucket wheel drive are equipped with output controls for controlling the fluid delivery in conformity with the encountered digging resistance and that a control conduit branched off from a pressure conduit leading to a hydraulic motor for driving the bucket wheel is connected to an output limiting valve located in a control circuit which includes an adjusting device connected through conduits to a manually operable control for varying the delivery and the delivery direction of the pump for actuating the hydraulic motor for pivoting the upper structure of the dredge. The fluid delivery of the pumps to the hydraulic motor employed for driving the track laying mechanism being conveyed to the hydraulic motor for driving the bucket wheel when the track laying mechanism is not to be operated.