Studies on the Development of a Screw Type Soybean Thresher (Part II)

Threshing Characteristics of Screw Type and Tangential Type Threshing Mechanisms

Abstract

The outline and the proper specification of main structures of the screw type threshing mechanism were presented in the previous report. Basic threshing characteristics of this mechanism such as threshing efficiency, percentage of damaged grains, grain passing rate through the concave and power requirement for threshing were compared with the tangential threshing mechanisms with single or double cylinder which are widely applied to the conventional soybean threshers, and the relative advantages of the screw type threshing mechanism were clarified. Further, the suitable threshing conditions such as cylinder speeds, moisture contents of soybean and grain feed rate were proposed.