Google Patents US2121486A - Hopper and agitatorĭownload PDF Info Publication number US2121486A US2121486A US121795A US12179537A US2121486A US 2121486 A US2121486 A US 2121486A US 121795 A US121795 A US 121795A US 12179537 A US12179537 A US 12179537A US 2121486 A US2121486 A US 2121486A Authority US United States Prior art keywords hopper shaft agitator bin drum Prior art date Legal status (The legal status is an assumption and is not a legal conclusion.