| Notoginseng is one of rare medicinal herbs in China,and it is mainly grown inWenshan Prefecture Yunnan Province.until December 2017,the planting area of notoginseng has reached 66666.7 hm~2.At present,the main planting pattern is through manual operation,and the labor intensity is very high and the sowing quality is discrepant.However,there is no precision seeding device suitable for in notoginseng manmade mushroomshed.Therefore,the mechanization planting of notoginseng has important practical significance.Notoginseng is planted on small plots of land,the planting density and the requirement of seeding precision are high.In order to meet the agronomic requirements of Notoginseng precision sowing,this paper carried out experiments and research on the precision feeding machine for hill-drop planter for panax notoginseng.Concrete study content as follows:(1)Through on-the-spot investigation at the planting base of Panax notoginseng,the seeds were grading based on the physical characteristics of Panax notoginseng seeds.A hole wheel precision metering device was designed.The EDEM discrete element simulation software was used to analyze the seeding process of seed metering.using four factors and five level orthogonal design method for metering device test bench.Experimental results show that the better combination type holes wheel speed 35 r/min,hole depth is 6 mm,hole diameter is 8 mm,at this time the grain from the qualified index can reach was 93.81,replay index was 2.39,leakage sowing index was3.8.(2)This article designed a hill seed-metering,cavity parts are cone-shaped.The theoretical analysis determines the main structural parameters of the pressure-reducing mechanism,and analyzes the stress of the working process of the pressure hole,and determines the relationship of the traction required by the pressure-hole mechanism.Using the method of EDEM discrete element simulation,three kinds of cavity-hole components with different sizes were simulated and simulated,and the centroid coordinate points of the particles outside the hole were simulated and the hole mass and pressure force were measured.(3)At homemade seeding test-bed,we studied the seeding performance.Experiment design used three factors five levels quadratic orthogonal rotation combination pricking hole column maximum diameter,forward velocity and dropping seeds point to the pricking hole roll distance.as influencing factors,qualified index,multiple index,missing index as the objective function.Based on the results of examination,we found that the fitting of the equations was good,the best parameter combination was pricking hole column maximum diameter of 27-35mm,forward velocity of 0.6-0.7m/s and dropping seeds point to the pricking hole roll distance of500mm,and under the optimal condition,the qualified index was greater than 90,the missing index was less than 5and the multiple index was less than 5.(4)Based on the structural principle of the key functional components,the precision feeding machine for hill-drop planter for panax notoginseng was designed.Introduce the working principle of the overall structure of the whole machine,and check the strength of the frame and connecting frame of the main supporting part of the seeder,the results showed that the function of each component of the hole-drilling seeder meets the design requirements,and it is hopeful to solve the problem of mechanized seeding in Panax notoginseng.(5)The field sowing performance test results showed,with the increase of the seeder’s operation speed,the average particle distance increased gradually,the qualified rate first increased and then decreased,the standard deviation showed an increasing trend,and the coefficient of variation gradually increased.The forward velocity of 0.35 m/s,the qualified index was 93.5,the average particle pitch is 5.87mm,the standard deviation is0.33,the coefficient of variation is 5.62,and the seeding effect is the best. |
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