| Most of the domestic potato harvesters are based on the type of single medium and small chain.The common phenomena of medium and small potato harvesters include: easy to plug,high resistance,high rate of damaged potatoes and low level of mechanization.At the same time,potato mulch also caused serious "white pollution" and other issues.Under the background of the mechanization of the agricultural industry,potato harvesting machines with high economic returns,good operating quality,high reliability and complete functions have become a trend.In this project,a potato harvester and plastic film recovery machine based on hydraulic transmission control is designed.Hydraulic instead of mechanical transmission reduces the loss caused by friction,and can also achieve adjustable speed.The content of research mainly includes:(1)A potato harvester with a residual film recovery function was designed to achieve rapid potato harvesting while recovering residual film from the field simultaneously.The main innovations and selections were made for the potato hydraulic drive system and the mulching equipment.In the AMESim software,the hydraulic system is simulated.The simulation results show that the load rotation speed is in agreement with the actual demand.The rotation speed does not lag behind the target rotation speed,and the stability of the load rotation speed is good.(2)Due to the time-consuming and laborious unloading of the film after the conventional film-recovering mechanism recovers the film,a pyramid-type residual film recovery mechanism has been designed.In order to improve the recovery rate of the plastic film,the film-receiving teeth were installed on the film-rolling mechanism and the curling mechanism was statically simulated.The maximum stress point of the film-rolling mechanism at the deformation location was at both ends of the mechanism,which was approximately 36 Mpa.Membrane mechanism can work long hours.(3)In order to reduce the rate of skin breakage in potato harvesting process,discrete element simulation analysis was conducted on the force and soil disturbance during potato harvesting.It was found that the excavation resistance and the rate of skin breakage are all at the lowest when the current advance speed is 0.8m/s.(4)In order to study the influence of various factors on the recovery rate of plastic film and the rate of potato peeling,response surface analysis was used to conduct orthogonal analysis of the test results,and the test results were verified in the field.The test results show that the film recovery rate is mainly related to the film thickness,and the thicker the film is,the higher the recovery rate is.When the thickness is certain,the plastic film recovery rate is the largest when the traveling speed is 1m/s.The rate of potato breakage is mainly related to the depth of excavation.The deeper the depth of excavation,the lower the rate of broken skin.When the excavation depth is 26 cm,the rate of broken skin is the lowest. |
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