Desigin Of A Small Electric Leaf Vegetables Harvester

Mechanized production of vegetables research in our country starts relatively late,but with the vigorous development and popularization in recent years,its scale has been expanding.In the mechanized industry of vegetables,harvest is the most time-consuming and most labor-consuming part.There are many kinds of vegetables in our country,such as leaf vegetables,root vegetables and fruit vegetables.The studies of root vegetables and fruit vegetables harvesting machinery in our country are getting mature,some prototypes have been popularized in market.But the research for leaf vegetables harvesting machinery is still blank,the harvest of leaf vegetables mainly depends on labor force.With the intensification of aging and urbanization,the agricultural labor force is decreasing,the production efficiency is becoming low,and the cost is increasing year by year.Therefore,the development of advanced vegetable harvesting technology is of great significance.This thesis is aimed to design a small electric leaf vegetables harvester which can harvest vegetables planted in greenhouse automatically,and this machine can harvest many types of leaf vegetables which have similar shape.Specific research contents are as follows:1.The overall scheme of small electric leaf vegetables harvester was designed and power demand was analyzed.According to the harvesting needs of vegetables,harvesting machinery had to complete tasks including harvesting,transportation,stubble height adjustment and so on.The design adopted a reciprocating cutting device,a reel wheel type conveying device and a push rod type device.To choose the appropriate motor model,the power requirement of each component was calculated.2.The main components of small electric leaf vegetables harvester were designed and selected.Structures and working principles of the cutting device,the conveying device,the cutting height adjusting device and the walking device were determined firstly.Then structures of cutter,transmission mechanism,conveyor belt,reel wheel,drive shaft were designed.At last,the frame part was designed on the premise of meeting the installation and work requirements.CATIA software was used to complete the three-dimensional modeling of each part and the virtual prototype assembly verified the rationality of the harvester design.3.The kinematic analysis of reciprocating cutter for small electric leaf vegetables harvester was conducted.In order to gain the reasonable cutting speed,cutting diagrams under 4 different cutting speed cases were compared.ADAMS software was used to carry on the kinematics simulation of the cutter.Thus,the correctness of design was testified.4.The mechanical properties analysis of the driving shaft and the frame parts of the small electric leaf vegetables harvester were implemented.The finite element analysis method was applied to analyze the structure of linear static on the drive shaft and the frame in ANSYS-Workbench software,the displacement and stress distribution were obtained.The results showed that the stresses and deformations of the drive shaft and the frame were in accordance with the allowable range of the material.The modal analysis of the frame was carried out,and the 6 order vibration mode of the frame was obtained.Furthermore,the weak position of the frame was analyzed,which provided theoretical support for the machining of the prototype.5.The prototype manufacture and test analysis of small electric leaf vegetables harvester were carried on.The prototype machine of leaf vegetables harvester was made.The operating efficiency,leakage rate,power consumption and other factors were taken as the evaluation criteria to conduct experiments.The results showed that the working efficiency of the harvester is 0.1hm2/h,the leakage rate is about 2.7%,and the power consumption is about 12.8kW.h/hm2,which verified the feasibility of the harvesting operation of the small electric leaf vegetables harvester.Small electric leaf vegetables harvester designed in this paper can complete vegetables cutting,conveying and collecting work in one time,which greatly reduces the labor intensity and improves the harvesting efficiency.Since the harvester utilizes battery as its power,the operation process is pollution-free.