Bran screening machine with automatic rice husk cleaning function

The utility model provides a chaff screening machine with an automatic chaff cleaning function. The chaff screening machine comprises a chaff screening machine body, and a conveying screen belt is arranged in the chaff screening machine body. A chipping collecting box is further arranged at the bottom of the bran screening machine body; the chipping collecting box is located below the conveying screen belt, the top of the chipping collecting box is open, and the chipping collecting box communicates with the interior of the bran screening machine body; a discharging opening is formed in the chipping collecting box; at least one screw rod used for pushing chippings to move towards the direction of the discharge hole is also arranged in the chipping collecting box; a driving motor is mounted on the outer side wall of the scrap collecting box; the two ends of the screw rod are rotationally installed in the scrap collecting box through bearings, and one end of the screw rod penetrates through the side wall of the