Automatic packaging line coding device and using method thereof

The invention relates to an automatic packaging line code printing device and a using method thereof.The code printing device comprises a conveying belt arranged on a support and used for conveying product bags, a plurality of sliding blocks sequentially arranged in the conveying direction are further arranged on the outer side face, making contact with the product bags, of the conveying belt, and relief printing plates for printing characters are arranged on the top faces of the sliding blocks; and an ink box for supplementing ink to the relief printing plate is also arranged on the bracket. When the device is used, the sliding block is located on the outer side face, making contact with a product bag, of the conveying belt and is conveyed along with the conveying belt, so that after the product bag is placed on the conveying belt, the conveying belt is pressed on the relief printing plate, and printing ink on the relief printing plate is printed on a packaging bag through the dead weight of the product bag;