Tooless concave fastener

An agricultural harvester machine, comprising:

• a thresher including a thresher rotor received within a thresher housing, the thresher housing including a support frame and a plurality of concave grates mounted on the support frame:
• the support frame including a support flange, the support flange having a plurality of support flange apertures defined therethrough;
• each concave grate including a mounting flange having at least one mounting flange aperture defined therethrough, the mounting flange aperture being aligned with one of the support flange apertures when the concave grate is mounted on the support frame;
• and
• one or more latch assemblies connecting each of the concave grates to the support frame, each of the latch assemblies including:
• a carriage bolt including a threaded shaft having an enlarged head at one end with a non-circular shoulder adjacent the enlarged head, the shaft being dimensioned to be received through the aligned mounting flange aperture and support flange aperture with the non-circular shoulder closely received in one of the apertures to prevent rotation of the carriage bolt;
• a thrust washer received about the carriage bolt;
• a nut threadedly received on the threaded shaft;
• and
• a cam lever pivotally attached to the nut to pivot about a pivot axis perpendicular to a length of the threaded shaft, the cam lever including a cam surface configured to engage the thrust washer, the cam lever being pivotable from an unlatched position to a latched position such that engagement of the cam surface with the thrust washer during pivotal motion of the cam lever biases the thrust washer toward the enlarged head to thereby latch the mounting flange of the concave grate to the support flange of the support frame.