Design and experiment of a centrifugal filling and cleaning high-speed precision seed metering device for maize

In this paper, a centrifugal filling and cleaning high-speed precision seed metering device for maize is designed based on the principle of centrifugal force generated by high-speed circular motion of seeds. Through theoretical analysis and calculation, the seeding tray and front shell of the seed metering device are designed so that the seeds can use centrifugal force for filling, cleaning, releasing, and returning. The seed metering device has a simple structure and can perform high-speed and precise seeding. A response surface experiment of central composite design was conducted with feeding and seeding speeds as experimental factors, and the omission rate, repeated rate, and pass rate as performance evaluation indexes. Through response surface experiment optimization, it was deduced that the highest seeding performance was achieved when the feeding and seeding speeds were 18.72 seeds/s and 15.12 km/h, respectively. Under these conditions, the omission, repeated, and pass rates were 2.21, 5.21, and 92.58%, respectively. The results of response surface experiment showed that, when the seeding speed of the centrifugal filling and cleaning high-speed precision seed metering device for maize is in the range of 10–20 km/h, the pass rate can be greater than 90%. In addition, the speed curve of feeding and seeding fitted from the bench experiment results is effective and reliable, which allows the seed metering device to achieve a precision seeding in a speed range of 10–20 km/h. The power of the air-suction seed metering device is 470.24 W when seeding at a speed of 14 km/h. Moreover, the power of the centrifugal filling and cleaning high-speed precision seed metering device is only 10.94 W when seeding at a speed of 20 km/h, and the energy consumption during seeding is much lower than that of the air-suction seed metering device, which performs cleaner production.