DESIGN AND EXPERIMENT ON PRECISION SEED METERING DEVICE FOR NARROW-ROW AND DENSE PLANTING OF SOYBEAN

The capability of existing precision seeding for soybean narrow row seeder is limited, to address these limitations; we designed a seed metering device. In this study, the structure and working principle of a precision seed metering device was analyzed, and the structural parameters of the seed counterbore seeding wheel for the seed metering device was designed and optimized. Field tests were carried out with the working speed, forward speed, and inclined angle as test factors, and the seeding qualified index and variation coefficient of uniformity as test indexes. The results showed that: the influence order of the factors affecting on the seeding qualified index, from high to low, was found to the working speed, inclined angle and forward speed. For the variation coefficient of uniformity, the influence order, from high to low, was as follows: the working speed, forward speed and inclined angle. Based on the optimization analysis performed using the Design Expert 8.0.6, it is concluded that when the working speed, forward speed, and inclined angle are 36.50 r/min, 1.47 m/s, and 4.11 degrees, respectively, the seeding performance was optimal. The seeding qualified index and variation coefficient of uniformity were 90.37% and 12.87%, respectively, to reach the national seeding standard grade. This study provides a research basis and technical reference for the design and development of precision seed devices.