| Jiangsu province is the origin of artemisia selengensis planting industry,and artemisia selengensis planting area is vast and the artemisia selengensis consumer market is huge.The degree of agricultural mechanization of artemisia industry determines whether the artemisia planting industry in this province can continue to develop at a high speed and steadily in the new era.The growth environment and variety characteristics of artemisia determine the difficult problems such as low harvest efficiency,high cost and complex working procedure.On the market,mature artemisia harvest machinery is less,and the general leaf vegetables harvest machine is difficult to complete artemisia harvest.At present,it is very difficult to achieve orderly and low-damage harvest by mechanized harvesting operation,so it is necessary to overcome the problems of disorder and disorder of artemisia selengensis in the field,to overcome the impact of in-motion cutting in the face of potholes,and to overcome the problems of delicate artemisia selengensis stem which is easily damaged by clamping conveyer.In order to overcome the above difficulties and improve the whole mechanization level of artemisia selengensis production,it is necessary to design a kind of artemisia selengensis harvester,which can complete the mechanized harvesting operation under the traction of small crawler power machinery to meet the requirements of harvesting mechanization operation.Based on the analysis of the advantages and disadvantages of the existing models,this paper has carried on the optimization design and the structure improvement,and designs and develops a kind of harvesting machine which can realize orderly harvesting,subsoil cutting,low loss conveying and the function of removing leaves.The machine can improve the harvest efficiency of artemisia selengensis,realize mechanized harvest,reduce the labor intensity of farmers and save production cost.The specific research content is as follows:(1)Test and analysis of mechanical properties of stem of artemisia selengensis.Because the mechanical properties of stem of artemisia selengensis are not the same as those of common vegetables,the research on the stem mechanics of artemisia selengensis is the research premise for the design of each key component and the whole machine.The mechanical properties such as shear strength,compressive strength and elastic modulus of stem of artemisia selengensis were obtained by experiments,which provided theoretical basis for the design of cutting device and gripper.(2)Design of the whole scheme of the harvesting machine of artemisia selengensis.The requirements of harvesting operation and the design requirements of the machine were clarified,and the design schemes of several key devices of the harvester were compared and analyzed,so as to understand the advantages and disadvantages of each scheme,and the design scheme that could overcome the practical difficulties in the process of harvesting was put forward.The harvester needs to complete the tasks of harvesting,conveying,adjusting the height of stubble and removing leaves.In the design scheme,the cutting device adopts reciprocating cutting device,the conveying device adopts flexible belt conveying device,and the adjusting device of cutting stubble height adopts screw nut device.Then the power consumption of the unit is analyzed and calculated to determine the power of each component device and select the appropriate motor model.(3)Design of key components of the harvester for artemisia selengensis.According to the design scheme of the whole machine,the main parameters of each key device are determined,and the corresponding parameters of the main components of cutting,clamping conveying and blade dividing devices are calculated,and the corresponding strength and stiffness checking analysis is carried out to verify the rationality of the design of key components.According to the relative position of each device,the frame of the whole machine is designed reasonably.The 3d modeling software UG was used to model the key device and the frame of the whole machine.Finally,the 3d model of the whole machine was established and the virtual prototype was assembled.(4)Finite element simulation analysis of the key components of the harvester of artemisia selengensis.Using AN SYS-Workbench to analyze the structural statics of the frame of the harvester,the displacement and stress cloud map are obtained,and the results show that the stress and deformation of the frame and the key parts are in accordance with the allowable range of the material.The modal analysis of the frame of the whole machine was carried out with ANSYS-Workbench software,and the 6-order mode was obtained.According to the previous 6-order mode and the output frequency of the motor,the analysis shows that the selected motor will not cause the frame resonance phenomenon when working.The explicit dynamics analysis was carried out on the stalk cutting model of artemisia selengensis,and the optimal cutter reciprocating speed was obtained through the simulation results,so that the cutter could cut the stalk of artemisia selengensis in one time,and the cutting effect was ideal.(5)Trial production and test results analysis of the prototype of the harvester of artemisia selengensis.The prototype of harvesting machine of artemisia selengensis was trialproduced,and the field test was carried out according to the test specification.Then checking the harvester can effectively complete the requirements of orderly harvesting,low-loss transportation and defoliation,analyzing the working effect of the prototype,and verifying that the performance of the harvester meets the design requirements.The artemisia selengensis harvester designed in this paper can complete the cutting,conveying and leaf removal of artemisia selengensis at one time,effectively solve the main problems existing in the harvesting of artemisia selengensis,improve the operation quality and efficiency of artemisia selengensis mechanized harvesting,greatly reduce the labor intensity and save the production cost. |
PDF Full Text Request