Combine harvester grain cleaning apparatus

A combine harvester comprising an oscillating thresher pan for conveying a chaff/grain stream rearwardly to a rear edge from where the grain/chaff stream falls under gravity into a cleaning unit which includes at least one vibrating cleaning pan onto which the grain/chaff stream falls, the cleaning unit comprising a fan for generating a cleaning airstream which is directed through the falling grain/chaff stream, wherein the cleaning pan has fixed thereto a damping surface comprising a sheet of rubber-based material to damp bounce of kernels falling thereupon, wherein the sheet of rubber-based material is provided with a plurality of transverse ribs.

A combine harvester comprising an oscillating thresher pan for conveying a chaff/grain stream rearwardly to a rear edge from where the grain/chaff stream falls under gravity into a cleaning unit which includes a first cleaning pan onto which the grain/chaff stream falls and a second cleaning pan, the cleaning unit comprising a fan for generating a cleaning airstream which is directed through the falling grain/chaff stream, wherein at least one of the first cleaning pan and the second cleaning pan has fixed thereto a damping surface to damp bounce of kernels falling thereupon, wherein the first cleaning pan comprises a vibrating cascade pan and the second cleaning pan comprises a vibrating chaffer pan, wherein the grain/chaff stream falls from said rear edge of the thresher pan onto the cascade pan before falling from a rear edge of the cascade pan onto the chaffer pan, and wherein parallel cleaning airstreams are directed through the falling grain/chaff stream between the respective pans, wherein at least one of the thresher pan and cascade pan comprises a rubber-coated comb of rods or grid attached to the rear edge thereof to divert long straw and weeds away from the cascading grain flow.