a feed elevator located within the feeder housing. The crop material then passes through a threshing and separating mechanism. In a rotary combine, the threshing and separating mechanism comprises a rotor, a threshing concave, a rotor cage, and a separating grate. As crop material passes between the rotor, the threshing concave and the separating grate, the crop material is impacted and/or rubbed, thereby causing the grain to separate from stalk material. The stalk material that is separated from the grain is called MOG (material other than grain).
After passing through the threshing and separating assembly, the grain and MOG are deposited on to a grain cleaning system. The grain cleaning system of a typical combine comprises a pair of adjustable cleaning sieves, often referred to as a chaffer sievethe influence of gravity, into an auger trough positioned along the lowermost edge of the collection panel. The auger trough is typically positioned near the forward end of the cleaning sieves and extends along the width of the sieves. The grain collected in the auger trough is then moved by an auger towards the side of the combine where it is raised by a grain elevator and deposited into a storage tank.
The grain collecting auger comprises an axle or shaft about which a blade (called the auger flighting) is spirally positioned. As the collecting auger is rotated, the flighting moves the grain along the length of the auger and into the base or boot of the grain elevator. The grain elevator typically comprises a housing having a series