1. The machine is equipped with a stand-alone type vibrating trash-cleaning unit which can be flexibly installed on the front part of the stacker. 2. The machine is equipped with a movable trash-cleaning part which makes the trash-cleaning operation easier and more convenient. 3. The trash-cleaning part adopts transmission with multiple belts and double clips and vibrationally cleans trash in a rotating manner and with an independent speed (adjustable). 4. This machine is provided with a blower which can blow off the paper scraps on the paperboard. Machine speed can be adjusted according to printing machine