Design And Experiment Of Air Blowing Anti-blocking Soybean No-tillage Planter

In recent years,with the large-scale development and application of conservation tillage technology,no-tillage planters have developed rapidly.The soybean no-till seeder on the market is prone to raising the ditching parts during sowing,causing problems of hanging grass and stubble,and the seeds are easily sowed on the stubble of the straw,causing the phenomenon of racking and drying seeds,which seriously affects the sowing quality and operating efficiency.In view of this situation,based on the research of no-tillage seeding machines at home and abroad,combined with the local requirements of sowing agronomy,a kind of air blowing anti-blocking soybean no-tillage seeder was designed in this paper,The seeder adopted the combination method of blower fan and shallow rotary knife,and uses the airflow to blow the straw on the back ridge to achieve the purpose of sowing in "clean area" under no-till environment.The specific research content is as follows:(1)The overall scheme design of air blowing anti-blocking soybean no-tillage planter.Through a large number of references to relevant literatures of no-tillage seeders at home and abroad,compare and analyze the working mechanism and design features of the anti-blocking devices of existing no-tillage planters,a reasonable anti-blocking method was determined,and the whole machine was drawn using UG NX10.0 3D model.(2)Design of anti-blocking device and cleaning stubble device.The installation angle of the blower fan blade tip is determined to be 13.6 °,the installation angle of the blade root is 32.0 °,and the fan shaft speed is 1800 ? 2500 r/min;Through calculation and theoretical analysis,it is determined that the rotation speed of the shallow rotary blade is 300 r/min,the turning radius of the blade is 250 mm,and the penetration depth of the shallow rotary knife is 20mm-50mm;The radial direction between adjacent tool holders was equal to 90°,the axial spacing is 225 mm,and the terminal velocity of the blades ranged from 4.5 to 6.2 m/s.(3)Design of fertilizing device and seeding device.The machine realized side fertilization of soybean planting in 6 rows,with a row spacing of 40cm;The fertilizing opener adopts a hoe shovel opener,its soil penetration angle is 34 °,the soil penetration performance is good,and the amount of soil disturbance is small;Through comparative analysis,the outer trough wheel fertilizer distributor and finger clip type seed distributor were selected,and the diameter of the cracking wheel was determined to be 350 mm in combination with the agronomic requirements of soybean seeding.(4)Finite element analysis is carried out on the key components.Using ANSYS /Workbench software to perform static analysis on the shallow rotary knife and the frame,and the corresponding loads and constraints were applied to them to obtain the maximum stress and strain values;According to the characteristics of selected materials,the rationality of the design of shallow rotary knife and frame is verified,which can meet the requirements of no-tillage seeder.(5)Prototype manufacture and field experiment.The structure and technical parameters of the machine are determined and complete prototype processing trial production.The results of field experiments showed that under the conditions of machine speed of 4 km/h and theoretical grain spacing of 12 cm,straw clearance rate was 83.19%,grain spacing eligibility index was 91.47%,reseeding index was 2.90%,missed sowing index was 4.69%,coefficient of variation was 9.48%,seed depth eligibility rate was 86.67% and seed drying rate was 1.32%.The machine has good passability and all the indicators meet the design requirements.