基于流变特性分析的菠菜有序收获机夹持输送装置研究  

Clamping Conveyer Device of Ordered Spinach Harvester Based on Rheological Property Analysis

作　　者：邹亮亮[1,2] 刘雪美 李金光[1] 牛子孺 宋烨本 苑进 ZOU Liangliang;LIU Xuemei;LI Jinguang;NIU Ziru;SONG Yeben;YUAN Jin(College of Mechanical and Electronic Engineering, Shandong Agricultural University, Taian 271018, China;Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment, Taian 271018, China)

机构地区：[1]山东农业大学机械与电子工程学院,泰安271018 [2]山东省园艺机械与装备重点实验室,泰安271018

出　　处：《农业机械学报》2019年第10期72-79,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51675317);国家重点研发计划项目(2017YFD0701103-3)

摘　　要：针对菠菜有序收获夹持输送过程中极易出现挤压损伤的问题,基于菠菜植株的流变特性对夹持输送过程中工作参数对损伤的影响进行了研究。首先提出了一种菠菜夹持输送装置,阐述其工作原理和机械结构,分析了浮动夹持机构与菠菜植株的互作关系;通过Burgers粘弹性模型构建了菠菜植株夹持输送作用下的流变本构方程,利用菠菜植株的蠕变试验,确定流变本构方程系数;在不考虑弹性变形和粘塑性变形前提下求得菠菜塑性变形表达式,并将菠菜塑性变形量作为衡量菠菜机械损伤程度的评价指标;选择对损伤影响较大的夹持轮当量弹性系数和输送速度,分析其对菠菜塑性变形量的影响,得到最小塑性变形下的作业条件;选取输送速度和当量弹性系数三水平的5组参数组合进行分析研究,得到不同参数组合下的夹持输送过程中夹持力与时间的关系方程,以菠菜最小塑性变形量为目标,实现低损伤收获。为了验证用菠菜流变特性分析工作参数对菠菜损伤影响的可行性,进行了夹持输送试验,试验结果表明:当输送速度为25 mm/s、当量弹性系数为2 N/mm时,输送成功率为93.3%,菠菜损伤率为6.7%,夹持输送效果较好。In the process of harvest, spinach plants could be damaged easily by clamping conveyer device. To solve the problem, the rheological property of spinach plants was used to analyze the gripping delivery parameters on the effect of damage to spinach. Firstly, a kind of spinach gripping delivery device was put forward, its working principle and the mechanical structure were expounded, the relationship of floating clamping device with spinach plants was analyzed. Rheological constitutive equation of spinach plants under the action of extrusion was constructed by Burgers viscoelastic model. By the creep test, the constitutive equation coefficients of spinach plant samples were obtained. Without considering elastic deformation and viscoplastic deformation, the constitutive equation of spinach plastic deformation was obtained and the degree of plastic deformation was used to measure spinach mechanical damage. The influence of equivalent modulus of elasticity, transmission speed on plastic deformation was researched. The operation condition of minimum plastic deformation was obtained and it could achieve low damage harvest at this time. Three kinds of transmission speed and three kinds of equivalent modulus of elasticity were selected, and the five groups of parameters were studied. The constitutive equation of clamping force with time under different working parameters was obtained, and the operation condition for minimum plastic deformation could be obtained by the equation. Finally, a gripping delivery test platform was set up, the result of the experiment showed that when the equivalent modulus of elasticity was 2 N/mm, the transmission speed was 25 mm/s, the success rate of conveying spinach was 93.3% and the injury rate of spinach was 6.7%, the effect of gripping delivery was better. The experiment proved that the rheological properties of the spinach could be used to analyze of the influence of working parameters on the spinach damage feasibility. The research provided the theoretical basis and technical reference

关 键 词：菠菜 低损伤收获 夹持输送装置 流变特性 

分 类 号：S225.92[农业科学—农业机械化工程]