Experimental Study On Full-feeding Picking Characteristics Of Peanut Combined Harvesting

Peanut is most international competitive oil crops of China,and Chinese peanut production is the first in the world.It plays an important role in the national economy.With the regulation of agricultural structure and the market increasingly obvious,and with the acceleration of land circulation,peanut industry has shown a new trend of development.Harvesting operation is the key and difficult point of peanut mechanized production.It is an important task for the development of peanut harvesting mechanization in China to develop highly efficient and stable peanut combine harvester.Picking is the necessary link and key link in the process of mechanized harvesting,which determines the quality of peanut harvesting.Based on the review of the technology and equipment of peanut mechanized harvesting technology at home and abroad,this paper starts from the study of peanut full-feeding picking characteristics,and combines theory and simulation analysis to carry out an in-depth study on the fruit picking technology with high efficiency peanut combine harvester.Through the system test,the optimal design of the picking device is made,the picking performance is stabilized,the work is more reliable,and the operating performance index such as the removal rate,the breakage rate and the entrainment loss rate are improved effectively.The main contents and conclusions are as follows:(1)The research on the characteristics of fruit picking based on the moisture content and mechanical properties of peanut during the period of harvest was carried out.Through experiment it is concluded that each part of the peanut plant moisture content decreased rapidly a few days before the drying stage.After 4 to 5 days of drying,the water content of peanut pods was reduced to about 25%,and the ratio of peanut fruit to seedling was about 1;the pull-off force of the seedling node is larger than that of the stalk node.The pulling force increases first and then decreases,in the whole drying process;the pulling force is at a low level,after 4 to 5 days of drying.The peanut seedling and the shear force decreased with the decrease of water content.Peanut pods mechanics characteristic test,it is concluded that the maximum force required pressure,vertical pressure minimum when the destruction of peanut pods.(2)Design of key components for tandem tangential flow feeding picking device and picking and fruit picking dynamics analysis.Through the design of key parts,the position relation between the picking roller and the concave sieve is rationally arranged.The stress condition of peanut plant in cutting drum and the moving process between rollers were analyzed.The kinematic and dynamic behavior characteristics of peanut plant in the fruit picking roller were studied,and the mechanism of fruit picking operation was proved.Three-dimensional software is used to establish the three-dimensional model of the fruit picking device,and the modal analysis is carried out to verify the rationality of the structural design.(3)The research on the performance of picking was carried out to optimize the structure parameters and operating parameters.The effects of three factors(picking roller speed and feed amount and picking gap)on peanut picking rate and damage rate and entrainment loss rate were studied by single factor test.The influencing factors of the influencing factors on the index are discussed,and the mathematical model is established by SPSS software.Based on the response surface method,the regression model was established,and the optimal parameter combination was determined by multi parameter optimization analysis,that is,the drum speed is 234rad/min,the feeding amount is 3.15kg/s,and the picking gap is 30 mm.Finally,it is verified that under the optimum parameters,the net removal rate is 96.80%,the breakage rate is about 4.91%,and the loss rate is about 1.68%.