Patent ID: 6908378

Claim:
An extension for a helical flight extending around a front inlet end of a rotor of a threshing system of an agricultural combine, the rotor being rotatable in a predetermined rotational direction about a rotational axis therethrough and the flight including a leading edge extending radially outwardly from the front inlet end of the rotor and a rearwardly facing helical crop flow surface extending rearwardly from the leading edge at a first predetermined angle of attack relative to a plane perpendicular to the rotational axis, for conveying crop materials from adjacent the inlet end of the rotor radially outwardly and rearwardly when the rotor is rotated, the extension comprising: an elongate blade shape member removably mountable in radially outwardly extending relation along the radially outwardly extending leading edge of the flight, the blade shape member being disposed so as to be located forwardly of the leading edge of the flight with respect to the predetermined rotational direction along at least a substantial portion of a radial extent thereof when mounted thereon, the blade shape member having a leading edge having a curved swept back shape, and a rearwardly facing crop flow surface extending rearwardly with respect to the predetermined rotational direction from the leading edge of the blade shape member to the helical crop flow surface of the flight along substantially the entire radial extent of the blade member and is oriented at a second predetermined angle of attack less than the first predetermined angle of attack, such that when the rotor is rotated in the predetermined direction the member will accelerate crop material that comes into contact with the leading edge thereof radially outwardly and rearwardly onto the flight and generate a rearwardly directed air flow.