Device and method for improving grinding efficacy in gravity-fed grinding machines

The present invention regulates the delivery of feedstock to the fragmentation zone in a gravity-fed comminuting machine and reduces the ejection of feed materials by means of a rotating cylinder located at an offset position above the rotor. Rotationally mounted on an axis parallel to and above, but offset from, the axis of the rotor, this cylinder serves primarily as a striking surface, or anvil. The continual rotation of the anvil, in the opposite rotational direction as the rotor and with much slower rotational speed, assists in agitating the feed material, alleviating the problems of feed chute obstructions and feed aggregation. The cylinder forces the feed materials into contact with the rotor teeth through continuous rotation and provides a novel tooth design to improve efficacy and reduce wear.