Design Of Mechanical-Pneumatic Combined Metering Device For Potato

To solve the problem of limited seeding speed for the scoop belt type seeding device and large negative pressure required for the air suction type seed metering device,a mechanical-pneumatic combined metering device for potato was designed.The overall structure and working principle of the seeding device was analyzed.Based on the theoretical analysis of the potato seed stress,the structure and parameters of the key components of the metering device were determined.The main research is to develop a new kind of air scooper with a hybrid potato planter,to get the high coupling of the pneumatic field and the gravity field,to increase the rate of the plant and the rate of the seed and the stability rate of the plant,to increase the planting rate,and to build a kind of energy scoop with the physical characteristics of the potato;An air suction scoop belt was designed based on the agronomic requirements of potato planting.Based on the kinematics and dynamics analysis of potato in the process of seed selection,carrying and seeding,a combined seed arrangement device with suction scoop was designed.SolidWorks,a 3d mechanical design software,is used to design the components of the seeder.The gravity field simulation analysis was carried out on the mechanical structure of the designed seeder by using EDEM software,and the flow field simulation analysis was carried out on the designed seeder by using Fluent software,so as to guide the optimization and improvement of the mechanical structure of the seeder.Conducting suction spoon with combined-type metering device test: will the final 3 d after the simulation optimization structure into detail drawing and assembly drawing,production line kind of entity,through the test of single factor experiment to get the reasonable scope of working parameters.Taking the main air chamber negative pressure,the clearing wind speed and the seeding belt speed as the test factors,the three-factor three-level quadratic regression orthogonal test was carried out with the missing seed rate,the multiple seed rate and the qualified seed rate as the test indicators.According to the test results,the mathematical model of response surface was established,and the influence of various factors on the test index was comprehensively analyzed.At the same time,the experimental factors were optimized to meet the requirements of high precision seeding.The interaction factor analysis shows that the order of influence of the missing seed rate was seeding belt speed>clearing wind speed>main air chamber negative pressure;the order of influence of the multiple seed rate was clearing wind speed>main air chamber negative pressure>seeding belt speed;the order of influence of the qualified seed rate was the seeding belt speed > clearing wind speed > main air chamber negative pressure.The model optimization results showed that when the negative pressure of the main gas chamber was 6.46 kPa,the clearing wind speed was 31.94 m/s,and the belt seeding speed was 0.5 m/s,the seeding effect was optimal.The average missing seed rate of the five trials was 1.64%,the average of the multiple seed rate was 4.21%,and the qualified seed rate was 94.15%,which was consistent with the optimization results and was superior to the agricultural industry standards.This study can provide theoretical basis and technical support for efficient seeding of potato seed.