Staggered spiral rasp bar segments for axial flow combines

In an axial flow combine harvester having a mobile frame;

• a threshing rotor rotatably mounted on said frame for rotation about a generally longitudinally extending axis, said threshing rotor being operable to thresh crop material and separate grain from said crop material, said rotor including a threshing section having mounted thereon a rasp bar for rotation with said rotor;
• a concave supported on said frame adjacent said threshing rotor for cooperation with said rasp bar to thresh crop material;
• crop gathering means forwardly mounted on said frame to collect crop material and feed said crop material into said threshing and separating rotor;
• and drive means for operatively powering said threshing rotor and said crop gathering means, the improvement comprising:
• said rasp bar being divided into a plurality of longitudinally extending segments, each said segment being connected to said threshing rotor at a position circumferentially offset relative to the adjacent said rasp bar segment, each said rasp bar segment being spirally curved at least partially around the axis of rotation of said rotor and being positioned in a non-overlapping relationship relative to the axis of said threshing rotor with respect to circumferentially adjacent rasp bar segments.