Design And Experimental Study On The Peanut Pickup Device With Shovel Tooth And Two Cylinders

Peanut is not only an important oil crop but also a cash crop,which plays an important role in the security of edible oil and increasing farmer’s income.Although our country is a big peanut production country,the mechanization harvest technology level is far lower than developed countries such as America,and the harvest efficiency is low and high loss rate.T Two stage harvesting is the main method of peanut harvesting in China,with picking being the key link in peanut harvesting,which largely determines the efficiency and degree of loss of peanut harvesting.Based on the follow-up research of the National Natural Fund project(project number: 51575367),aiming at the problems such as plant throwing,accumulation,leakage and fruit dropping occurring in the process of the existing peanut pickup harvester in our country,this paper based on the mechanism and structure of the peanut pickup,designed a combined shovel-double roller type peanut pickup device and conducted a performance test.The main research contents and conclusions of this paper are as follows:(1)Study on physical and mechanical characteristics of peanut plants.It mainly included the measurement and statistical analysis of peanut plant morphological characteristics.The variation of water content of peanut plant and the variation of tensile strength of peanut stalk node,seedling stalk node and stalk with water content were analyzed.The friction characteristics of peanut plants and its variation with water content were analyzed.The effects of different laying methods and shovel tooth insertion Angle on the lifting height of peanut plants were analyzed.(2)The principle and overall scheme of peanut shovel-pick-push picking were put forward.Based on the analysis of the smooth picking process and working conditions of peanut plants,in view of the structural characteristics,advantages and disadvantages of the existing peanut picking device and the movement characteristics of peanut plants,the principle of shovel-pick-push picking device was put forward and the overall scheme of the shovel tooths-double roller combined picking mechanism was determined.(3)Design of key components of peanut pickup device.Based on the principle of shovel-pick-push pickup and the overall structure,combined with the test results of physical and mechanical characteristics,the basic structure of the shovel teeth was determined and the buried Angle was determined to be 20°.In this paper,the tooth structure of moving seedling is designed,which is transitioned from a straight line to an arc and has a front Angle in the straight line segment.The structure of picking tooth with bending Angle of back is designed.A semi-closed guard plate structure is designed.Through the kinematics simulation of the picking mechanism,the basic range of picking speed ratio is determined from 1.1 to 1.3.(4)Development of peanut picking test device.In order to test a new type of peanut picking device,a hanging peanut picking device with a width of 900 mm was designed and developed.The working face of the shovel teeth is designed as an arc face,and the spacing between adjacent shovel teeth is 60 mm.The diameter of picking drum is designed to be 460 mm,and the diameter of rolling seedling is designed to be 550 mm.The guard plate is composed of straight line and arc,and the gap of the guard plate is 10 mm.The bottom of the straight line section of the guard plate is designed as a "shrinking" structure;The transmission route of pickup test device is designed.(5)Field performance test of peanut pickup device.The field performance test was carried out by the experimental device of peanut picking.On the basis of single factor test,orthogonal test and response surface analysis were carried out.The effects of forward speed,picking speed ratio and radius of shovel teeth on picking rate and falling rate of peanuts were studied.The regression equation was established and the working parameters were optimized.Finally,the optimal parameter combination is as follows: forward speed 1.2m/s,picking speed ratio 1.2,radius of shovel teeth 498 mm,picking rate 98.97%,falling rate 2.25%,which can well meet the requirements of peanut harvesting.