Abstract: A wheel assembly for driven or non-driven trolleys or the like, comprising at least one set of wheels (10, 11) having at least three wheels (11) which are mounted on the trolley by a bearing means (13). The bearing means (13) has a center of rotation (C) which is located on the axial center line of the set of wheels (10, 11) and is connected to the trolley, at a distance from this center of rotation (C). When the wheels (11) encounter an abstacle as the trolley is run, the bearing means (13) will rotate relative to the set of wheels (10, 11), which causes shifting of the center of gravity so as to permit the set of wheels to climb over the abstract without the need of any appreciable additional effort.