Research On The Design Of Combined Harvesting Technology And Device Of Pulling White Radish

China is the largest producer of white radish in the world,and the planting scope covers all parts of the country,but the mechanization production level and efficiency of white radish are low.Harvest is an important link in the white radish industry,at present,the harvesting of white radish in China is mainly artificial harvesting,and some enterprises and colleges carry out the research of mechanization harvest of white radish.However,the performance of the machine is still imperfection,and it is mainly semi-mechanized,which requires a large amount of labor,high labor intensity and low operating efficiency.A few are transformed from other rhizome harvesters,but the adaptability and reliability are poor.In order to solve the problems of imperfect performance,poor adaptability and reliability of white radish harvesting mechanization,based on the analysis of white radish planting environment,growth characteristics and harvest characteristics,a pull-out white radish combine harvester was designed in this paper.The research content of this paper mainly about the following parts:1.Study on geometrical characteristic parameters of radish.According to the design requirements of the key components of the white radish harvester,the geometric characteristic parameters and soil parameters of the mature white radish were measured,and the data were statistically analyzed to analyze its variation range and distribution law.The pull-out test of white radish under natural condition and the tensile test of stem and leaf of white radish were carried out.The relationship between pull-out force and geometric characteristics of white radish and the maximum tensile strength of stem and leaf at different speeds were obtained.2.Study on dynamic characteristics of pullout force of white radish.The structure and working principle of the harvester are studied.The working process mainly includes loose soil,clamping,transportation,cutting and collection.Based on the experimental statistics in Chapter 2,the design and parameter optimization of the white radish combined harvester were carried out,mainly including the cherry holding device,clamping device,soil loosening device and cherry cutting device.The static stress analysis and modal analysis of the key components were carried out to ensure that the key components could meet the requirements of normal operation.3.Analysis of dynamic characteristics of radish extraction.The contact mechanics models between soil and radish and between soil and soil were constructed by using EEPA contact model in EDEM simulation software,and the extraction process was simulated under different soil co MPactness,installation position of shovel,extraction Angle and extraction speed.and the extraction process is simulated under different soil co MPactness,installation position of loosening shovel,pulling angle and pulling speed.Through the simulation,the relationship between soil loosening,pulling angle and soil pulling force is obtained.4.The power of harvester is matched and calculated,and the whole machine transmission system design.The assembly and processing of the prototype are completed,and the main technical parameters of the prototype are defined.and the influence of working speed and inclination Angle of clamping device on working quality was analyzed.The field performance test shows that the operation performance of the pull-out white radish combine harvester meets the design requirements,the damage rate was less than 2.7%,the leakage rate was less than1.8%,and the harvest efficiency was 0.08～0.26 hm~2/h,which were all better than the relevant standards.