Design And Experiment Of In-situ Threshing Sunflower Seed Harvesting Device

Xinjiang sunflower adopts the segmented harvesting method of inserting plate for drying and taking plate for threshing.The harvesting process depends on labor and the degree of mechanization is low.Aiming at the harvesting method of taking plate for threshing in Xinjiang sunflower,combined with the advantages of rice and wheat threshing and harvesting technology,this paper designs an in-situ threshing sunflower seed harvester that directly threshes in the state of inserting plate.Based on the material characteristics of sunflower,taking the threshing device and grain collection device as the research key points,this paper adopts the methods of theoretical analysis and experimental verification to carry out the prototype design,production and optimization.The research content includes the following points:(1)Study on physical characteristics of sunflower after inserting plate and drying in Xinjiang.The planting plot of sunflower SH363 under the segmented harvesting mode of sunflower in Urumqi was investigated.The results show that the plant spacing of sunflower is 50～70 cm,the small row spacing is40cm,the large row spacing is 90cm,the height of sunflower disc is 65cm～95 cm,the average length diameter of sunflower seed is 27.1 mm,the average short diameter is 11.0mm,the average thickness is 5.8mm,the average mass of single seed is 0.24 g,the average moisture content of sunflower seed in the suitable harvest period is 19.87%,the average suspension speed is 7.53 m/s,and the sliding friction angle between sunflower seed and steel plate is about 29.1°,The static friction coefficient is 0.54.The parameters provide basic data for the machine design of sunflower seed harvesting device.(2)The whole structure of the in-situ threshing sunflower seed harvesting device is designed.Based on the research and analysis of the threshing and harvesting technology of sunflower taking plate and the threshing technology of rice and wheat,a sunflower seed harvesting device is designed,the structure and working principle of the whole harvesting device are described,and the relevant design parameters are established.The whole machine mainly includes original threshing device,grain collection device,pneumatic conveying device,grain separation device,transmission system,walking device,etc..(3)Structural design and theoretical analysis of key parts.By analyzing the feeding process of the sunflower tray under the condition of inserting the tray,the"T"shaped frame structure is designed,and the clearance for the sunflower tray and the sunflower rod is reserved throughout the frame;The threshing is carried out by the combination of hitting roller and threshing brush.Three kinds of hitting elements of hitting roller are designed.The gap between hitting roller and sunflower tray support plate is 20 mm.The form of threshing brush is the original tray brush,and the brush wire material is polypropylene;The pneumatic conveying device of sunflower seeds is designed,and the diameter of the conveying pipeline is determined to be(?)90 mm,the effective volume of sealed aggregate box is 0.286 m~3.(4)Manufacture of test prototype and experimental research.Select factor indicators to verify the harvest performance of the device and determine the operation parameter range of each part,Taking the non threshing rate and damage rate of edible sunflower seeds as the test index,and taking the threshing brush speed,machine operation speed and beating roller speed as the test factors,the orthogonal test is carried out to analyze the test results and optimize the working parameters of the prototype.When the threshing brush speed is 130 r/min and the machine travel speed is 0.3m/s,When the rotating speed of the striking roller is8～0r/min,the non degreasing rate is 7.11%and the damage rate is 1.13%.