tray 17 forming the start of the lower arc 9 and the support plate 13 a passage 19 is provided through which an endless belt arrangement 20 which advances in a direction corresponding to the feed direction of the web runs from the outside into the interior of the arc 9 belt arrangement 20 traverses the arc between the web 1 and the bottom of the tray 17 in the illustrated embodiment the belt arrangement 20 consists of a screen belt which is driven in a controlled manner so as to ensure the transport of the stacked web of material 1 through the lower arc 9 in conjunction with the component of force resulting from the height different 21 between the inlet and the outlet of the device 10 in order to prevent the layers 22 of the web 1 from floating up a hold down device 23 is disposed in the lower arc 9 region at a distance above the bottom of the tray 17 or above the belt arrangement 20 in the illustrated embodiment it consists of three rollers 24 which are adjacent to each other in the feed direction of the web 1 and rotate about transversal axis however a revolving endless belt arrangement 26 which extends across the width of the web and the shape of which fits the bottom of the arc 9 in the region facing the bottom of the tray 17.