RESULTS OF ANALYTICAL RESEARCH OF THE SEED PROCESSOR OF THE IMPROVED SOWING SECTION OF THE PNEUMATIC SEEDER

Abstract

According to preliminary research, the primary factor influencing the accuracy of seed placement by pneumatic seeders is the process of transferring seeds from the metering device to the point of direct entry into the furrow formed by the coulter in the soil. The first factor is related to the high velocity of the air stream, which increases the risk of seed dislodgement from the seed boot and its placement outside the furrow. This problem can be addressed by installing a seed retarder above the seed boot. The second factor lies in the imperfect shape of the seed channel in the seed boot. Seeder developers, aiming to create an "ideal" seed bed in the soil, often underestimate the importance of the shape of the seed channel. Due to the high speeds at which modern pneumatic seeders operate (1.5–4.2 m/s) and their constant vibration, seeds in the seed channel of the seed boot constantly collide with its walls, leading to changes in direction and speed of movement. This chaotic seed movement results in decreased seeding accuracy. The third factor is the complete absence or incorrect installation of a seed retarder, which should prevent seed dislodgement from the bottom of the furrow. As a result of the analytical studies, the kinematics of seed motion after ejection from the seed boot and rebound from the furrow bottom and seed retarder were considered. The obtained dependencies include the maximum height of the parabolic seed trajectory y3`, the difference in distance between the points of rebound from the ground surface and the distance traveled by the seeder Δx from the initial seed velocity Vp0, the angle of their ejection α, the height of the seed retarder placement Hu, and the angle of its inclination β. By satisfying the conditions and for the obtained dependencies in Wolfram Cloud, the following rational parameters were obtained: α = 47°, β = 0°, Hu < 0.134 m. To ensure consistent seed placement at the center of the furrow bottom after rebounding from the seed retarder with a slight trajectory deviation (± 0.01 m), the profile shape of its working surface should be parabolic with the focus at point pf = 0.134 m.