THRESHING AND SEPARATING SYSTEM FOR AN AGRICULTURAL HARVESTER

An agricultural harvester (1) defines a longitudinal axis (A1) in a travel direction of the harvester (1) and includes a chassis (2); and a threshing and separating system (11) carried by the chassis (2). The threshing and separating system (11) includes a concave (23); a shaft (44) defining an axis of rotation (AR) which is parallel to the concave (23) and transverse to the longitudinal axis (A1); and a plurality of slats (46, 46A, 46B) rotated by the shaft (44) and configured to move crop material against the concave (23). The agricultural harvester (1) is characterized in that the slats (46, 46A, 46B) have a helical shape winding around the axis of rotation (AR). Said plurality of slats (46A, 46B) includes a first set of slats (46A) being predominantly on the left side of the shaft (44) and having a left-handed helical shape, and a second set of slats (46B) being predominantly on the right side of the shaft (44) and having a right-handed helical shape. At least one slat (46A) of said first set of slats (46A) is staggered relative to a closest slat (46B) of said second set of slats (46B), such that a portion of a slat length (SL) of said at least one slat (46A) is overlapped with one or more adjacent slats (46B) of said second set.