Design and Experimental Study of a Dual-Side-Disturbance-Facilitated Air-Suction Precision Seed Metering Device for Corn

To address the issue of a poor seed-filling performance and seeding quality in air-suction corn seed metering devices during high-speed operation, an energy-efficient precision corn seeder with dual-side-disturbance-facilitated guiding slots is designed. The dual-side-disturbance-promoting method effectively increases the seed agitation, directing the corn seeds toward the suction holes and improving the seed-filling quality. The theoretical design of the dual-side guiding slot angles results in an upper-side guiding slot angle range of 29° to 19° and a lower-side guiding slot angle range of 72° to 90°. Bench tests are conducted to further optimize the parameter range, with the negative suction chamber pressure, upper-side guiding slot angle, and lower-side guiding slot angle as the experimental factors and the seedling qualification rate, missed sowing rate, and double-sowing rate as the evaluation indicators. An orthogonal experiment is carried out to analyze the interaction effects of factors on the evaluation indicators, followed by parameter optimization and verification tests. When the negative suction chamber pressure is 3.7 kPa, the upper-side guiding slot angle is 26.9°, and the lower-side guiding slot angle is 72.9°, the verification test results show a qualification index of 97.7%, a missed sowing index of 1.3%, and a row-spacing variation coefficient of 1%. The operational speed adaptability test results show that when the working speed is ≤14 km/h, the seed metering device achieves a qualification index above 97.1%, a missed sowing index below 1.5%, and a double sowing index below 1.4%, indicating good adaptability to working speeds. The comparison test results show that when the operating speed is between 8 and 12 km/h, the air-suction seed metering device with dual-side-disturbance-facilitated guiding slots achieves a 2.1% increase in the qualification index, significantly improving seeding quality. The energy consumption comparison test results indicate that under the same operational speed and approximately equal seeding quality, the air-suction seed metering device with dual-side guiding slots and dual-side-disturbance-facilitated air suction requires a reduction in negative pressure of more than 0.7 kPa, resulting in lower energy consumption.