Classified screening device for production of bio-organic fertilizer

The grading screening device for producing the bio-organic fertilizer comprises a screening box and a driving assembly, a feeding port is formed in the upper end of the screening box, three secondary screening ports are formed in the side face of the screening box at equal intervals, a mounting column is mounted on one side of the screening box, and a discharging port is formed in the other side of the screening box. Three mounting cavities are formed in the mounting column at equal intervals; the driving assembly comprises three connecting shafts, the three connecting shafts are rotationally connected with the inner walls of the upper ends and the lower ends of the three mounting cavities correspondingly, micro-control motors are mounted at the upper ends of the three connecting shafts correspondingly, supporting shafts are mounted outside the three connecting shafts correspondingly, mounting frames matched with the secondary screening opening are mounted on one sides of the three supporting shafts correspon