Cleaning mechanism of 3D printer

The utility model relates to a cleaning mechanism of a 3D printer. The device comprises a screw rod, a polish rod, a sliding block, a moving plate, a transmission device and two supports, the two supports are fixedly installed on the two sides of a printing platform respectively, the two ends of the screw rod are rotatably installed on the two supports, the sliding block is provided with a first through hole and a threaded hole matched with the screw rod, the screw rod is sleeved with the sliding block through the threaded hole, and the polish rod penetrates through the through hole to be fixedly installed on the supports; the sliding block is fixedly connected with a moving plate, a brush is arranged below the moving plate, and the bottom of the brush is attached to the upper surface of the printing platform; the transmission device comprises a driving wheel, a conveying belt and a transmission wheel, the driving wheel is connected with a driven wheel through the conveying belt, and the driven wheel sleeves