| Xinjiang is one of the main cotton producing areas in China,It plays a positive role in promoting regional economic development.Continuous improvement of mechanization level of plant protection is an important basis for ensuring high,stable,safe,environmental protection and sustainable development of agriculture.Accelerate the development of efficient,safe and environmentally-friendly plant protection technology and equipment.It is particularly urgent to solve the problems that the fog droplets caused by close planting mode can not penetrate the canopy of crops and the effect of medication on the middle and lower parts of plants in Xinjiang.At the same time,it can promote the upgrading of plant protection machinery and speed up the operation level of plant protection machinery.On the basis of the research of spray machines at home and abroad,a kind of seedling separating device of plant protection machinery for dense planting crops is designed.Through the combination of digitized model and field experiment,the best parameter combination of through performance and plant disturbance performance can be achieved,to determine the type of seedling separating device of plant protection machinery for dense planting crops,to solve the problem that the fog droplets of densely planted crops can not penetrate the canopy,and to increase the deposition of fog droplets in the middle and lower parts of plants.The main research contents and conclusions are as follows:(1)Study on physical characteristics of dense planting cotton.Through field investigation,the physical characteristics of cotton plant in Xinjiang were analyzed.The height,the number of leaves,the planting density,the diameter of cotton stalk and the moisture content of cotton plant all had a direct impact on the mechanical performance of the seedling separating device.Through the analysis of the working object and working conditions of the seedling separating device,the variation range of different investigation factors is obtained,which can be used as the basis for the design and optimization of the seedling separating device.(2)the design of seedling separator surface.Based on the study of the physical characteristics of densely planted cotton crops,the form and working principle of the seedling separator surface were determined,and the seedling separator surface was theoretically designed and analyzed.Through statistical analysis of the number of branches and the deformation of branches acting on the seedling separator,the pressure on the divider panel was obtained.The three surfaces were analyzed by using Solidworks software to determine the reliability of the design.(3)design of seedling separating device.Based on the investigation and analysis of the working objects and working conditions of seedling separating device,the overall design of the threshing device of plant protection machinery for dense crops was determined,and the key components were analyzed and designed theoretically.Through the overall design of the separator,the separator not only plays the role of branch and sprinkler protection for cotton,but also opens a space in the cotton canopy which is conducive to spray diffusion and improves the effect of spraying.Through the design of sprinkler installation position,the spray droplets can be spread to the cotton canopy on both sides and the rear area of the separator to further improve the uniformity of the spray droplets distribution and the amount of liquid deposition in the cotton canopy.Through the drag-proof design of cotton plant,the separator can protect cotton peach when it encounters excessive resistance caused by cross-winding of cotton branches.(4)design parameters and test results of seedling separating parts.According to the design requirements,the design parameter acquisition test and the performance test of the seedling separating device are carried out.According to the experiment,when the physical parameters of the split surface are consistent,the faster the speed of the sprayer is in the range of 3km/h-5km/h,the greater the pressure of the distributor is;the pressure on the parabolic surface is the minimum when the walking speed is the same.Therefore,parabolic surface is the optimal surface.Through the experiment on the effect of applying pesticides to the seedling separating parts,it is proved that the structure design of the seedling separating parts can meet the technical requirements. |
