Designing And Experimental Study On Key Mechanism Of Trailed Cabbage Harvester

Cabbage is one of the main vegetable varieties in our country.Because of its high productivity,good quality,good cold resistance,convenient storage and transportation,there are many farmers for planting it.At present,China's cabbage harvesting machinery is still in its infancy,there are problems such as poor harvest stability and poor harvest quality.Aiming at a series of problems of domestic cabbage planting such as it occupy more human,difficult operation and mass production,planting loss is severe,combines the actual conditions of farmers,this paper designed a traction type cabbage harvester on the basis of experiment,emphasis on designing and optimization for the double spiral conveying mechanism,the feasibility of the mechanism is verified throuth the experiment.(1)Physical properties study of cabbage.The height,diameter and quality of the early maturing cabbage were analyzed in laboratory.The detaching force and roots moisture content of the cabbage under different soil condition were measured.The results showed that the average detaching force of cabbage is 192.1 N;the water content of cabbage root four different parts of up,middle,bottom and base are decreased gradually,respectively are 89.42%,86.9%,83.775%and 78.34%.(2)Overall structural design of the cabbage harvester.Through the investigation of cabbage planting mode in Hei Longjiang province of china,the design scheme of cabbage harvester was confirmed.The traction mode,matched power,harvest rows and main technical parameters of key institutions were determined.This machine is mainly composed of double screw extraction and conveying mechanism,coping mechanism,root cutting mechanism,defoliation mechanism,conveying mechanism and transmission system.The main working parts were analyzed and designed.Choose flexible belt with coping mechanism,chain conveyer,disc cutter for root cutting mechanism,and hydraulic belt roller for defoliation mechanism.(3)Design and experimental optimization of double screw extraction and conveying mechanism of cabbage harvester.The double helix extraction mechanism was analyzed with mechanics,and the force analysis model was established,and concluded the impact factor of cabbage in normal transport conditions.Using four factors at two levels quadratic orthogonal rotating combination design method,four factors of screw speed,screw spacing,screw pitch and the angle between screw and the ground are selected,take the delivery rate and root cut failure rate as the objective function,using Design-Expert8.0.1 software for processing and analysis of the test data,with the method of multi target optimization for model optimization,and received the factor optimal combination which meet the response variable scope.The optimized structure parameters combination are the screw speed is 700 r/min,the screw spacing is 76 mm,the screw pitch is 68 mm,and the ground screw angle is 16 degrees.The delivery rate can reach 93.7%,the root cut failure rate is less than 3%,Meet the requirements of cabbage harvest.