Design And Experiment Of Seed-oriented Vibration Feeding Device For Flat Eggplant

China is the world’s largest producer of vegetables.In 2018,the country planted20,438,940 hectares of vegetables,including more than 3.3 million hectares were planted with peppers and tomatoes,the largest vegetable variety after Chinese cabbage.About 2/3 of the vegetables produced in China all year round are transplanted with seedlings.As we know,pneumatic seed drill has no size limit for the seeds and it causes little damage to the seeds.So it can achieve a high sowing precision for spherical seeds of leafy vegetables.However,it is difficult to achieve the same sowing effect when slowing flat solanaceae seeds because it’s easy to cause repeated sowing and seed leakage.Compared with spherical seeds,the fluidity of flat seeds is poor.Under the vibration of seeder feeding box,flat seeds will be accumulated in different positions at the suction hole of the row drum,resulting in a higher rate of multiple flat seeds in one hole.Therefore,based on the theory of vibration-supported seeding and conveying,this paper proposes a vibrating feeding device,which feeds a right amount of seeds to the suction hole to keep the seeds in the same position in the area,resulting in a consistent seed amount in the suction hole,so as to improve the sowing accuracy.The purpose of this study is to enable the seed feeding device to deliver seeds to the vicinity of the seed suction hole in a directional,accurate and stable manner.It is a guiding vibration device composed of a quantitative seed filling feature,a guiding filling plate,an electromagnetic vibrator and other key parts.The paper also discusses the physical and mechanical properties of flat seeds in order to provide reference for the structural design of the feeding device.The influence of V-shaped and straight-shaped guiding grooves on seed flow state on filling plate was analyzed by EDEM simulation.According to the advantages and disadvantages of the two guiding grooves,a seed filling plate with Y-shaped guiding groove was designed.According to the size of the suction hole spacing of the seed meter and the triaxial size of the seed,the angle of V-shaped area of Y-shaped groove is set to be 40°,and the length into the width of the straight groove is 30mm×8mm.The paper also defines the spacing between two intersecting oblique planes at 11 mm in the seed box,and the quantization reseeding mechanism of seed drill can form a monolayer in the filling plate at different speeds according to different production efficiencies based on the study of arch in granular materials and the basic sizes of flat seeds.By analyzing the motion state of seeds on the guiding plate,this paper has defined five factors affecting the relative sliding of the seed,namely,the static friction coefficient between the seed and the guiding plate,the installation angle of the guiding plate,the vibration direction angle,the vibration frequency and amplitude.According to the physical characteristics of the seeds,we set the installation angle of filling plate to 10° to make the seeds remain stationary in the initial state and the vibration angle to 25° to make the seeds move steadily on the filling plate.In order to further clarify the influence of vibration frequency amplitude on seed movement,this paper discusses the vibration characteristics of the seed filling plate by using the vibration detection system.In the study,as the vibration frequency is fixed at 100 Hz and the amplitude is adjustable,the vibration amptitude increases with the increase of voltage;when the vibration range is-55 V to 50 V,the amplitude variation of each groove of the guiding plate is similar.This study also tests the seed flow characteristics of capsicum peppers under the condition of vibration using the method of high-speed photography.The results show that the seed flow velocity increases with the increase of the amplitude of the seed feeding plate.And the flow state tests show that when the amplitude of Y direction of the seed feeding plate varies between 0.45μm and 0.54μm,seeds can be sowed rapidly in the guiding groove to form a monolayer,uniform and directional seed flow,achieving a good consistency of the seed flow velocity.This paper conducts comparative tests on the seeding effect of the guiding and unguiding vibration feeding device,and the results show that the seeding effect of capsicum peppers and tomatoes meet the qualification stipulated by the Industry Standards for Seeding Machines(DGT007-2019)under the condition of the production efficiency of 300 plates/hour,600 plates / hour and 900 plates / hour,with a yield of more than 95%,the empty rate is less than 5%.The experimental results also show that the guiding vibration feeding device can significantly improve the seeding rate of flat seeds and reduce the rate of multiple grains.