30 is also coupled by the shaft 29a with a gear or gear member 33 this gear 33 meshes with a gear or gear member 34 upon whose shaft 34a there is seated a gear or gear member 35 the gears 34 and 35 can be exchanged for different gears in order to vary the rotational speed of the lap roller 3 in relation to the rotational speed of the lap roller 2 the gear 35 meshes with a gear or gear member 36 upon the shaft 36a of which there is seated a gear or gear member 37 this gear 37 is connected by a suitable power transmitting or transmission element 38 here for instance a chain 38 with a gear or gear member 39 which is coupled to the shaft 3a of the lap roller 3 a brake mechanism or device 40a for the lap roller 2 has a clamp or gripper 40 or equivalent structure which acts upon a disk or plate 41 rigidly connected for rotation with the shaft 2a of the lap roller 2 in addition to the brake mechanism 40a or in lieu thereof there can be provided a similar brake mechanism or device 42a having a clamp or gripper 42 or equivalent structure which acts upon a disk or plate 43 rigidly connected for rotation with the shaft 3a of the lap roller 3 and which is provided for this lap roller 3 the schematically illustrated brake mechanisms 40a and 42a are thus here for instance disk brakes however it is of course possible to use other types of brake mechanisms yet in any case the brake mechanisms or any other provided.