Development of a Suitable Seed Metering Device for Cereals

Abstract

Wooden and metallic (cast aluminum alloy) metering device with four different cell shapes were designed and tested in the laboratory. The cell sizes were determined according to the physical dimensions of various paddy and wheat varieties. Wooden metering device offered excessive resistance to uniform flow of paddy seeds. The performance of the metallic metering device with a modified cup shaped cross-section of the flutes was found best among others and almost eliminated cell fill and seed damage problems. Such a device performed satisfactorily over a wide range of ground speed enabling it to be adapted to animal or power tiller. At lower linear CF II speeds (0.275 m/s) the seed discharged from the cells were in a group but, at higher cell speed (0.373 m/s) seed discharge pattern was found continuous. A recommendation was made for drilling as well as hill dropping of seeds with the same metering unit by changing gear ratio's between drive wheel and seed metering shafts.