Grain grading and impurity removing machine

The utility model relates to the field of grain processing equipment, in particular to a grain grading and impurity removing machine which comprises a grading chamber, a grading filter screen, a partition plate b, a supporting rod and a material pushing plate. An impurity removal chamber is vertically arranged on the left side of the grain separation chamber, and an impurity removal assembly is arranged on the impurity removal chamber; the grain separating filter screen is horizontally arranged on the inner wall of the grain separating chamber, and a plurality of arc-shaped grain separating filter screens which are sunken downwards are arranged on the grain separating filter screen; the bottom of the grading filter screen is divided into a plurality of grading storage cavities by a plurality of groups of partition plates b, and discharge holes are formed in the grading storage cavities; the supporting rods are horizontally and rotatably arranged on the inner wall of the grading chamber, the supporting rods ar