at least part of a rotatable bearing of the drum body on a drum supporting frame wherein the at least one drum drive unit includes a stationary drive part attached to the drum supporting frame and a rotatable drive part connected with the drum body the rotatable drive part of the drum drive unit is mounted on the drum body by a positive entrainment connection in a torque transmitting but longitudinally movable manner the entrainment connection rotatorily entrains the drum body in order to be able to transmit the rotary drive movements of the drive part to the drum body application_number US 201213552471 A description fig1 shows a self propelled surface milling cutter 1 such as a surface miner or asphalt milling cutter whose main working assembly forms a milling drum 2 to be rotatably driven about a horizontal axis on whose circumference cutting tools are mounted in order to millingly comminute a ground layer or asphalt layer the surface milling cutter 1 is moved continuously by means of the tracklaying gears 3 so that said milling drum 2 continuously experiences a feed movement the machine body 4 which is drivably supported on the ground by said tracklaying gears 3 and carries said milling drum 2 furthermore comprises conveying means for removing the milled material coming from the milling drum the milled material is charged onto a receiving conveyor 5 which transfers the material onto a loading conveyor 6 in order to load.