Design And Experimental Research Of Belt Type Corn Precision Metering Device

Corn is an important food crop in my country.With the improvement of the degree of mechanization of corn operations,people have higher and higher expectations for the yield of corn.To increase the yield level of corn,it is necessary to improve the seeding quality of corn,which requires improve the uniformity and consistency of the seeding device.At present,the distance between the seeding port and the seed bed in the domestic corn precision metering device is large,which causes the random movement of the seed to increase after falling into the seed bed,thereby affecting the uniformity and consistency of seeding.In response to the above problems,a new belt type corn precision metering device based on rubber material was proposed,which used the deformation characteristics of the rubber material to realize the deformation of the hole,completed the seed filling and seeding process,and took the seeds at high positions and casts them at low positions.The method reduced the mechanical damage of corn seeds,reduced the height of planting,and improved the uniformity and consistency of seeding.The main contents were as follows:(1)Structure design of belt metering device.According to the design requirements of the seed metering device,the structure and working principle of the seed metering device are determined,and the material of the seed metering belt is determined to be neoprene through literature and theoretical analysis;The diameter of the wheel ranged from 160～200mm,the speed of the filling wheel was 10～30r/min,and the size of the hole during filling was12～16mm,which provided a theoretical basis for the subsequent simulation test of the filling process and the bench test program.(2)Simulation Analysis of Seed Filling Process of seed metering device.The simulation test analysis of the seed filling process of the seed metering device is completed by the discrete element software,so as to further reduced the size range of the filling wheel and the hole Finally,the diameter of the filling wheel was 170 mm and the speed of the filling wheel was 20 r /min through the bench test.when the hole size was 14 mm during seed filling,the pass index of the seed metering device was 91.2%(the highest),which provided a basis for the design of the seeding prototype.(3)Design of belt type corn precision seeding machine.On the basis of theoretical analysis,simulation analysis and bench test,Completed the design and processing of the belt type corn precision seeder,including the opener,belt type precision seed metering device,transmission system,ground wheel and other parts design after selecting the model,it was finally determined that the seeding prototype was a single row.The seeding distance is 20 cm,the seeding depth is 3～5cm,and the distance from the seeding port to the seed bed is 15 cm.(4)Field test of belt corn precision seeding machine.Completed the measurement of the working performance of the seeding prototype,and finally determined the operating speed to be 8km/h.At this time,the average seeding depth pass rate of the seeder prototype was90.5%,and the average seeding grain distance pass index could reach 86.26%,which conformed the design requirements of the precision seeder(The qualified rate of seeding depth is 75%,and the qualified rate of seeding pitch is 80%),which proved that the seeding sample has good seeding uniformity.