DESIGN AND TEST OF VARIABLE DIAMETER PNEUMATIC DRUM TYPE BEAN SEED METERING DEVICE

The roller for seeds of different sizes, a variable-size pneumatic cylinder precision seed metering device was designed, which could realize the precision seeding of different diameter seeds without changing the roller. The structure and working principle of seed metering device were explained, and the structural parameters of the main components of the seed meter were determined. The ANSYS was used to analyse the influence of the size of the negative pressure inlet pipe and the shape of the eyelet on the airflow velocity in a negative pressure chamber. Based on the above optimal structure, the orthogonal experiment of seed metering device was carried out. Testing results showed: under the negative pressure of 4 kPa, roller speed of 16.93r/min and the wind speed of 11.48m/s, the seed metering device had the best seeding effect. The qualification rate of the seed metering device was 92.37%, the miss-seeding rate was 3.74% and the over-seeding rate was 3.88%.