IMPROVEMENTS IN AND TO COMBINE HARVESTERS

摘要

2130550 9316581 PCTABS00025 The invention is directed to an improved method and means of achieving the separation of relatively heavy threshed grain from lighter chaff/straw during the threshing operation in a combine harvester, wherein the crop materialbeing threshed by the threshing unit (12, 16) of the harvester is sujected to a jet of air which is directed between the underside of the concave (16) of the threshing unit (12) and the grain transfer means (18) which conveys threshed grain from the threshing unit (12) to an intake of a cleaning mechanism (22), the jet of air being effective to assist the delivery of the threshed material away from the threshing unit and to pre-clean the threshed grain by urging the chaff and strew into an airborne state prior to reaching the cleaning mechanism.