A Grain Cleaning Apparatus for a Combine Harvester

A grain cleaning apparatus for a combine harvester, comprising:

• a stratification pan for receiving material from a threshing system of the combine harvester;
• a set of dividers for dividing the material into lanes on the stratification pan, the dividers comprise partition walls which extend normally upwardly from a base plane of the stratification pan, the lanes extending in a fore-aft direction of the combine harvester, wherein at least some of the dividers are provided with a respective pivotable guide plate for guiding material into a lane at a selected side of the divider, wherein the guide plates each extend upwardly from the top of a respective divider and are pivoted at the top of the respective divider;
• and
• a controller configured to control the pivoting of the guide plates in dependence on a lateral inclination of the combine harvester.