Patent ID: 7021038

Claim:
A roll assembly for use on a crop conditioning machine comprising: first and second elongate rotatable rolls supported in a framework and disposed in adjacent parallel relationship, said first roll generally above said second roll; said first roll comprising an elongate cylindrical metallic body portion having a steel peripheral surface and at least one protruding metallic rib affixed to said steel peripheral surface, said rib being generally regular in cross-section and formed in a spiral along the length of said body portion, said rib is formed of a cylindrical rod of wear resistant metal welded to said peripheral surface; said second roll comprising an elongate cylindrical rigid body portion having a peripheral surface with a layer of hard elastomeric material affixed thereto, said elastomeric layer having at least one groove therein, said groove being formed in a spiral along the length of said rigid body portion and generally having a semi-circular cross-sectional configuration; said at least one groove has a side and a bottom, and said side being nearly perpendicular to the direction of crop travel; and said at least one rib and said at least one groove being arranged such that they intermesh as the rolls rotate in timed relationship such that the clearance between said at least one rib and said at least one groove is selectively adjustable with a minimum clearance between said at least one rib and said bottom of said at least on groove of 30 thousandths of an inch.