Abstract: A pivoting mid-floor section for use in a feeder house in an agricultural combine is located between the transverse drum and the transverse sprocket means. The pivoting mid-floor can move or adjust when a large volume of crop material is fed into the feeder house, while providing support for the conveyor chain along substantially the entire length of travel between the transverse drum and sprocket means, thus reducing the friction on the chain, and preventing the system slow downs that occurred in feeder house systems using a fixed mid-floor. Additionally, replaceable wear-resistant surfaces can be affixed to the runners or guides of the mid-floor to further extend wear life and reduce friction between the chain slats and mid-floor. The friction occurs between the wear pads on the runners or guides and the chain slats, rather than between the chain components and the mid-floor.

Abstract: A concave for an agricultural combine having an array of straight rectangular bars and straight round bars spaced from one another and extending axially of the rotor or cylinder to form a threshing surface and to form openings therebetween for grain to pass through. The round bars shed crop material to reduce plugging while the rectangular bars provide an aggressive threshing edge. Smaller diameter wires can be inserted between the round and rectangular bars to reduce the opening size for use with small grains.