Optimal Design And Experimental Research On Key Components Of Cabbage Harvester

In recent years,the country has made corresponding adjustments to the planting industry,and the cultivation of cabbage in China has developed extremely rapidly.In 2016,China’s cabbage planting area and output ranked first in the world.In the process of cabbage production,the labor force for harvesting accounts for about 40%of the total cabbage production.However,China’s cabbage is still dominated by manual harvesting,which leads to problems such as high labor intensity,high labor consumption,and low production efficiency,which seriously restricts our country.The development of the cabbage industry.Cabbage harvesting equipment technology in China is basically in its infancy.At present,there is no corresponding mechanical equipment in the market in China.In order to develop harvesting machinery suitable for the cabbage cultivation mode in China,this article relies on the national key research and development plan project"vegetable intelligent fine production technology"And equipment research and development"（project number:2017YFD0701300）.Combined with the research tasks,on the basis of the development of the cabbage harvester,the basic physical characteristics of the cabbage were studied.The physical properties of the cabbage were collected and the mechanical properties of the harvest were experimentally studied;through the dynamics and movement of the cabbage during the harvest process Analysis,design the key components of the cabbage harvester,determine the basic structural parameters of the cabbage harvester,and create the cabbage harvester;by theoretically analyzing the harvesting process of the cabbage harvester,determine the main factors and value ranges that affect the quality of the cabbage harvest,and carry out Experimental research;to determine the optimal parameter combination of cabbage harvester based on the evaluation index of cabbage damage rate and root cutting pass rate,and conduct field performance verification test.The main research contents and conclusions of this article are as follows:（1）Carrying out basic physical characteristic parameter collection and experimental study on harvesting mechanical properties of cabbage.The basic physical property parameters of cabbage were measured during the harvest period,and the mechanical properties of the cabbage rhizomes and spheres were squeezed and sheared.The test results show that the extraction force of cabbage is（189.25±50.06）N;the shear force of cabbage roots decreases with the increase of water content.When the water content reaches 92.3%,the maximum shear force is 102.3 N;The curve of the cutting force and displacement of the cabbage rhizome and the curve of the crushing force and displacement of the cabbage bulb,and the corresponding fitting equation is obtained:F_shear=-1.8131x²+31.374x-2.0673,the coefficient of determination is 0.9966;F_Squeeze=0.1654x²+23.802x+66.846,the coefficient of determination is 0.9996.（2）The structural design of the cabbage harvester was carried out,and the working principle and basic technical parameters of the whole machine were determined.Designed the reeling device of the cabbage harvester,and determined that the radius of the reeling device was 270 mm,the number of blades was 6,and the reeling speed ratioλwas 1.41,To increase the friction between the cabbage and the extraction rod,the extraction rod spacing is 28 mm;the cutting device is designed,the diameter of the disc knife is 200 mm,the overlapping part is 2 mm,the center distance is 198 mm,the knife disc is against the cabbage The angle between the normal reaction force of the rhizome and the X axis is 30.6°.At this time,the disc knife has good clamping performance;the clamping and conveying device is designed,which is mainly composed of two longitudinal conveyor belts with a spacing of 260 mm;The modal analysis of the disc cutter shows that the speed of the cutter head can effectively avoid the first 6natural frequencies at 200-500 r/min.（3）Through theoretical analysis of the key components of the cabbage harvester,the extraction rod speed,cutter speed,entrainment speed and tool advancement speed were determined as the influencing factors and value ranges,and the root cutting pass rate and cabbage damage rate were evaluated Indicators,on the basis of single-factor test,response surface optimization test design,using Design-Expert8.0 software,using CCD test design principles,design four factors and five levels of regression analysis test,and optimize the design parameters of the influencing factors,The test results show that the speed of the extraction rod is 129 r/min,the speed of the cutter is 398 r/min,the speed of the entrainment is 195 r/min,and the forward speed of the tool is 1.7 km/h.Under this condition,the maximum pass rate of root cutting is obtained.98.2%,the cabbage injury rate at this time was4.03%.The field verification test was carried out under the condition of this parameter combination,and the average pass rate of cabbage root cutting was 97.6%,and the damage rate of cabbage was 5.24%.