Development of a novel perforated type precision metering device for efficient and cleaner production of maize

This research presents a filling method that strips the kernels from the seed group to address the poor performance and energy efficiency of the mechanical maize metering devices at high-speed operating conditions. In addition, it advances the design of a novel perforated type precision seed-metering device. The quantity and posture of seed filling are restricted by the perforated ring, which creates a dispersed particle flow, thus enhancing the filling effect of the seeding plate and reducing energy consumption. The structural design of critical components is completed, and the principle of improving performance and energy efficiency is analyzed. The DEM simulation and bench experiment assisted in analyzing the effects of operating parameters on seed dynamic characteristics, seeding plate's filling performance, and operational energy consumption. Finally, the optimal parameter combination is determined. The result demonstrates that the number of teeth in the perforated ring was 21, accompanied by an improved seed-filling effect and lower energy consumption. The metering performance was optimal when the tooth length of the perforated ring was 8.65 mm, the center angle of the teeth was 8°, and the operating speed was 13.55 km/h. Moreover, the qualified rate was 94.5%, the multiple rate was 2.7%, and the leakage rate was 2.8%. The operating speed was in the range of 8–14 km/h, the qualified rate of the perforated seed-metering device was higher than 92.7 %, the leakage rate was lower than 5.4 %, the multiple rate was lower than 3.5 %, and the coefficient of performance was more than 9.2. Its energy efficiency was significantly better than that of the picker finger seed-metering device and the air-suction seed-metering device, thus satisfying the demands for an efficient and cleaner production of maize.