Patent ID: 7682236

Claim:
A harvested crop processing unit, comprising: a rotor, a rotor housing enclosing the rotor, the rotor housing further comprising: a cover element, said cover element having slots therein; a first group of helical guide rails mounted for movement relative to the cover element between an operating position in which they are located underneath the cover element for engaging the harvested crop and a non-operating position in which they are located above the cover element; a second group of helical guide rails mounted for movement in alternation with the first group of helical guide rails relative to the cover element between an operating position in which they are located underneath the cover element in engagement with the harvested crop and a non-operating position in which they are located above the cover element, wherein the second group of helical guide rails are provided with an inclination that differs from the inclination of the first group of helical guide rails, the helical guide rails being configured to be moved through the slots in the cover element between the operating position and the non-operating position; and a guide rail operating arrangement being operatively coupled to said first and second groups of guide rails for alternately moving said first and second groups of guide rails between their respective non-operating and operating positions.