Threshing and separating device and combine harvester having the same

A threshing and separating device comprising:

• a threshing mechanism comprising a first cylinder and a first concave located below the first cylinder;
• a separating mechanism comprising at least one second cylinder and a second concave located below the second cylinder;
• and
• an intermediate feeding mechanism between the threshing mechanism and the separating mechanism;
• wherein the first cylinder is rotatable about a first rotation axis and comprises a plurality of first rods parallel to the first rotation axis and uniformly arranged in a circumferential direction of the first cylinder, and each first rod is provided with a plurality of first threshing teeth each having a tip defining a first tip circle and the second cylinder is rotatable about a second rotation axis perpendicular to the first rotation axis;
• wherein the first concave comprises a wire-grate configuration, and a surface of the first concave facing the first cylinder is provided with no part protruding into the first tip circle;
• wherein the second cylinder comprises a forced feeding portion located at the front end of the second cylinder, and comprising a truncated cone and helical blades on the truncated cone;
• and a toothed-rod cylinder portion located behind the forced feeding portion with a plurality of second rods parallel to the second rotation axis and uniformly arranged in a circumferential direction of the toothed-rod cylinder portion, and each second rod is provided with a plurality of second threshing teeth each having a tip defining a second tip circle;
• and
• wherein the second concave has a wire-grate configuration and is provided with no part protruding into its corresponding second tip circle.