Sorting devices are successively guided along a sorting line and driven by means of a conveyor system. Each sorting device has a running carriage with running rollers guided in the sorting line's guide rails. In addition, the sorting device contains a means for receiving and ejecting individual parceled articles sent from a loading station. The conveyor system comprises a chain having chain links with flat undersides which are movably connected to each other. The chain links are rigidly connected to each running carriage of the sorting devices and project beyond these sorting devices in a transport direction. The joints between successive chain links are each bridged on their underside by a pre-tensioned leaf spring. The driving means is a friction wheel drive with a friction wheel engaging the chain links on their undersides. In an alternative embodiment of the invention, one chain link is rigidly connected to each of the running carriages of the sorting devices. Here, the conveyor system comprises a friction surface drive with at least three rotating elements each having a contact pressure-applying periphery that revolves about rotation axles. The rotation axles are connected with a rigid carrier and are spaced apart from each other along the sorting line so that the contact pressure-applying periphery of at least two of the rotating elements always non-positively cooperates with the contact pressure-receiving surface of at least one chain link.