Design And Experiment Of Artemisia Selengensis Leaf Removal Machine

Artemisia selengensis is rich in mineral elements.It is an edible and medicinal vegetable,which is widely planted in the middle and lower reaches of the Yangtze River in China.Artemisia selengensis can be harvested 3 to 4 stubbles at a time,and each crop needs to be removed.The leaf removal operation cycle is long,accounting for 50 to 60% of the production time of Artemisia selengensis.At present,the defoliation work is all done manually.The problems of low production efficiency and high cost of manual defoliation have become an important obstacle to the sustainable development of Artemisia selengensis industry.Therefore,the research and development of Artemisia selengensis defoliation machinery and equipment is imminent.To solve the mechanization problem of Artemisia selengensis leaf removal,based on the technical characteristics of leaf removal machinery and the principle of manual leaf removal method,this paper designs a leaf removal machine of Artemisia selengensis based on the physical and mechanical characteristics of Artemisia selengensis,which has played a certain reference significance for the research and development of leaf removal machinery.The specific work is as follows:(1)Determination and analysis of physical and mechanical properties of Artemisia selengensis.Taking the edible Artemisia selengensis as the research object,the geometric size of Artemisia selengensis was measured,and the length of Artemisia selengensis,the diameter of the bottom of the stem and the diameter of the clamping place were obtained.There are large differences,mainly concentrated in 305 to 380 mm,4.0 to 5.5mm,2.6 to3.8mm;the friction angles of Artemisia selengensis with different flexible leaf removal cushion materials were measured.The friction angles of Artemisia selengensis stem with defatted gauze,jute cloth and cotton cloth were 17.9°,21.5° and 20.2°,respectively.The load range of stem fracture was 10.2 to 30.6N by radial compression test.The axial tensile test showed that the load range of stem fracture was 9.5 to 31.9N;the tensile test of leaves in different directions showed that pulling leaves in the reverse growth direction was more conducive to leaf removal.(2)Research on mechanized leaf removal scheme and overall structure design.According to the field investigation,the mechanized leaf removal process and performance requirements of Artemisia selengensis were put forward.Referring to the principle of leaf removal machinery and manual leaf removal,three leaf removal schemes of double roller grasping,perforation and bionic were proposed.The functional test of the corresponding scheme was carried out.The results showed that the double-roll grasping scheme was easy to damage the stem and difficult to remove the leaves.The perforated scheme could effectively remove the leaves,but it was difficult for Artemisia selengensis to feed the appropriate mesh.The bionic scheme could better complete the leaf removal under the premise of ensuring the integrity of the stem.Three leaf removal schemes were comprehensively evaluated,and the bionic scheme was selected for subsequent research.Finally,the overall structure design of Artemisia selengensis leaf removal machine was completed based on the bionic scheme.(3)Design and analysis of conveying device and defoliation device.The Artemisia selengensis leaf removal machine is mainly composed of a conveying device and a leaf removal device,and the control system ensures accurate coordination between the two.The structural design of the conveying device is carried out,including the transmission shaft,the supporting plate.The theoretical analysis of the arrangement position of the flexible leaf removal cushion is carried out,and the installation spacing of the flexible leaf removal cushion is obtained when the production efficiency is high.The theoretical analysis and dynamic simulation analysis of the motion characteristics of the chain conveying parts verify the necessity of installing the guide rail,and the motion law of the double-row chain is obtained.The theoretical analysis and structural design of the leaf removal device are carried out,including the selection of pneumatic system components and stepping motor.In order to ensure the accurate coordination of the leaf removal device and the conveying device,combined with the analysis of the motion coordination,the circuit design and program design of the control system of the leaf removal device are completed.(4)Performance test of Artemisia selengensis leaf removal machine.The flexible leaf removal cushion materials,conveying speed,relative height of stem pressing cylinder and width of flexible leaf removal cushion material were selected as test factors.The single factor test was carried out with the net removal rate and damage rate as test indexes.The types of flexible leaf removal cushion materials were determined,and the influence of conveying speed,relative height of stem pressing cylinder and width of flexible leaf removal cushion on net removal rate and damage rate was obtained.The optimal value of the factors was selected to carry out the orthogonal test,and the optimal parameter combination of the test factors was obtained.According to the parameter combination,the validation experiment obtained a removal rate of 88.3% and a damage rate of 1.4%.