A concave apparatus for use in a combine harvester where the combine harvester includes:
- first and second side by side threshing and separating rotors;
- each rotor having associated therewith mounting arrangements for mounting a series of arcuate side by side concave elements, where each concave element extends angularly around a portion of the cylinder and where the side by side concave element are arranged at positions along the axis of the rotor;
- the mounting arrangement including an upper support for receiving an upper end of a respective concave element and a lower support for receiving a lower end of the respective concave element;
- the concave apparatus comprising:
- a concave support frame including two side rails arranged to lie in respective radial planes of the axis and extend around the portion of the cylinder and a plurality of transverse connecting bars at right angles to the side rails;
- a pair of concave inserts each for insertion into and mounting on the concave support frame;
- each concave insert having a rectangular arcuate body with a plurality of rub bars facing the rotor for cooperation therewith;
- the transverse connecting bars of the concave support frame including an upper bar, a center bar and a lower bar defining an upper rectangular space for an upper one of the pair of concave inserts and a lower rectangular space for a lower one of the pair of concave inserts;
- the upper concave insert having a lower transverse bar at a lower end and an upper transverse bar at an upper end;
- with the upper transverse bar of the upper concave insert having fastener holes to receive coupling fasteners for connection to the upper transverse bar of the concave support frame;
- with the lower transverse bar of the upper concave insert having fastener holes to receive coupling fasteners for connection to the center transverse bar of the concave support frame;
- the lower concave insert having a lower transverse bar at a lower end and an upper transverse bar at an upper end;
- with the upper transverse bar of the lower concave insert having fastener holes to receive coupling fasteners for connection to the center transverse bar of the concave support frame;
- with the lower transverse bar of the lower concave insert having fastener holes to receive coupling fasteners for connection to the lower transverse bar of the concave support frame;
- at least one of the lower transverse bar of the upper concave insert and the upper transverse bar of the lower concave insert having a projecting portion lying in an axial plane of the axis and projecting in a direction radially outwardly from the axis to a position beyond the center transverse bar of the concave frame;
- the projecting portion having a plurality of fastener holes therethrough.