Design And Experiment On Grading Equipment For Potato Seed Cutting Machine

Potatoes have a short growing period,high yield,and rich nutrition,which play an important role in accelerating farmers’poverty alleviation and becoming rich and optimizing China’s agricultural industrial structure.The realization of potato planting mechanization is of great significance to farmers’increase in production and income,and the improvement of potato production level.The cultivation mode of potato mechanized seeding is mainly based on cut potatoes,the quality of cut potatoes directly affect the quality of sowing and subsequent potato growth.Although the current potato cutting machine has high cutting efficiency,it has the problem of poor uniformity of the cut potato tubers,which makes it impossible to directly mechanize seeding,in order to provide suitable size potato seeds to the potato seed cutting machine to ensure the quality of cutting,it is necessary to grade the potato seeds before cutting.At present,most of the domestic and foreign potato grading equipment is large and expensive,and most of them are aimed at the grading of commercial potatoes.They cannot be used exclusively for potato seeds grading,and the grading precision cannot meet the requirements of potato seeds grading.Aiming at the above problems,this paper studies a grading equipment on a potato seed cutting machine,and carries out design,theoretical analysis,simulation analysis and experimental research on its main working components.The main content of this article is as follows:（1）The physical properties of two potato seeds（Youjin885,Xiabodi）in Heilongjiang area,including basic physical parameters,friction characteristics and mechanical properties of potato seeds,provide data support for subsequent structural design and simulation analysis.（2）Combining the technological process and agronomic requirements of cutting potato seeds before sowing,the key components of the grading equipment were designed,including the grading rollers,the grading roller wheel,the spacing adjustment device.（3）The movement law of potato seeds on the grading roller was explored,including the movement process of potato seeds on a single grading roller,potato seeds in a grading space composed of adjacent grading rollers,and potato seeds between adjacent grading rollers.The main factors affecting the grading precision and the value range of each factor are clarified.（4）Simulating the actual grading process,the EDEM software were used to carry out discrete element simulation of the designed grading equipment,determine the optimal grading roller spacing suitable for potato seeds grading,and verify that the grading equipment has a good grading effect.（5）Carry out experimental research on the designed grading equipment,take the grading precision and potato seeds breakage rate as the test indicators,and according to the influencing factors obtained from theoretical analysis,conduct orthogonal experiments with two potato seeds,and analyze the test results,seek the optimal combination of parameters,and conduct verification tests to verify that the designed grading equipment can meet the grading requirements.The results are as follows:（1）Combining the measured physical parameters of potato seeds,the structure of the grading rollers was determined.The diameter of the grading rollers is 100mm,the length of the wheel is 75mm,the height of the wheel stir piece is 25mm,and the height of the wheel guide plate is 15mm,the slope of the guide plate is 150°.The structure of the spacing adjustment device is designed as a combination of four-bar mechanisms,and the spacing adjustment device is simulated by ADAMS software,which verifies that the spacing adjustment device can guarantee the same change of the grading roller spacing and meet the requirements of spacing adjustment.（2）Through the analysis of the multiple movement processes of potato seeds on the grading rollers,including the movement process of potato seeds on a single grading roller,potato seeds in a grading space composed of adjacent grading rollers,and the main factors affecting the grading precision are determined,which is mainly composed of the rotation speed of the grading rollers,the number of grading rollers,and the feeding amount,and potato seeds between adjacent grading rollers.It is determined that the rotation speed of the grading rollers is90-120r·min^-1.The research provides theoretical reference for subsequent discrete element numerical simulation and experimental research.（3）The EDEM software were used to conduct discrete element simulation simulation on the designed grading equipment.Laser scanner was used to scan and establish two kinds of potato seeds（Youjin885,Xiabodi）models for single factor simulation experiments to determine the optimal grading roller spacing.The simulation test results show that the optimal grading roller spacing of Youjin885 potato seed is 123mm,and the optimal grading roller spacing of Xiabodi potato seed is 118mm,and verify that the grading equipment has a good grading effect.（4）Through the experimental research,it is verified that the designed grading equipment can meet the grading requirements of potato seeds cutting before sowing,and the optimal working parameters of Youjin885 potato seed and Xiabodi potato seed grading are determined.The rotation speed of the grading roller is 110r·min^-1,the number of grading rollers is 7,the feeding amount is 25t·h^-1,under the above conditions,the average grading precision of Youjin885 potato seed is 97.79%,and the average potato seed breakage rate is 1.80%,the average grading precision of Xiabodi potato seed is 96.48%,and the average potato seed breakage rate is 1.55%.The verification test shows that the designed grading equipment has a good grading effect and is highly adaptable to round potato seed and oval potato seed.It can meet the grading requirements of potato seed cutting before sowing.The grading equipment of the potato seed cutting machine designed in this research has a good grading effect for the grading operation of potato seeds before sowing in Heilongjiang area,and provides a high efficiency,high grading precision and low potato seed breakage rate grading equipment for the potato seed cutting machine.