【作者】 王方艳；

【导师】 张东兴；

【作者基本信息】 中国农业大学 ， 农业机械化工程， 2014， 博士

【摘要】 本文在研究国内外甜菜收获技术及农机装备的基础上,结合我国的甜菜种植模式和生产体制,对甜菜收获机械的关键装置进行了理论分析及试验研究,确定了甜菜联合收获的技术模式、关键技术理论及机构形式,并重点对导向系统、挖掘装置和输送清理装置进行了结构设计和参数优化,实现了甜菜块根的挖掘、输送、清理和收集工序的机械化作业,有效解决了甜菜收获机械化的关键技术难题,提升了收获机具的技术水平。主要研究内容及结论：(1)通过对我国甜菜种植农艺及国内外甜菜收获装备现状的调研,确定了甜菜的2段收获模式和工艺流程,提出了牵引式双行甜菜联合收获机械的设计方案及路线,确定了牵引式的油缸机位调节方式、机械-液压结合的传动系统、幅板式抛掷式机构、杆带式夹持输送装置和背负式收集箱等结构,并分析了甜菜联合收获机的工作原理及结构特点。(2)对甜菜的种植农艺和块根特性进行测定,得到了甜菜的田间分布状况、物理几何模型及压缩力学特性,研究了甜菜块根起拔力的影响因素,并确定了较优参数组合,为导向系统和挖掘装置的关键参数选定提供了参考。(3)借鉴国内外挖掘收获机具及其特点,确定了挖掘装置的结构及工作机理,明确了关键技术参数的关系,构建了挖掘装置的运动学模型及力学模型。运用ANSYS软件对挖掘装置进行了有限元分析,校验了装置结构的强度及变形。采用田间试验,建立了关键参数与挖掘性能指标之间的数学模型,并得到了最佳参数组合。(4)通过对现有导向技术及结构的分析,确定了导向系统结构及工作机理,分析了导向装置的参数关系和动力学特点。借助田间试验及响应曲面优化方法,建立了关键参数与导向效果指标的数学模型,研究了参数对试验指标的影响规律,并确定了参数范围及其最佳组合。(5)结合现有输送、清理机构及其特点,确定了输送清理装置的结构,研究了输送清理装置的工作原理、参数关系及运动特征,确定了输送清理装置的参数关系及范围。借助ADAMS仿真软件,研究了杆式链输送器的运动特性及输送链与输送链轮的相互作用,分析了关键参数对甜菜输送效果的影响,并确定了最佳参数组合,得到甜菜离开输送装置的加速度及速度。(6)通过田间收获性能试验,考察了样机的性能指标、作业质量、适用性和可靠性等情况。针对存在的不足做了进一步的改进和完善,使得样机基本满足收获要求。更多还原

【Abstract】 Based on the study of the sugar beet harvesting technology and agricultural machinery at home and abroad, the key equipment of sugar beet combine harvester was analyzed theoretically and experimentally to determine the beet harvest technology pattern, the key technical theory and institutional form, with reference to our country’s sugar beet planting patterns and production system. The key component of guiding system, digging equipment and conveying cleaning device was designed and optimized to realize the process of mechanical work of digging, transportation, cleaning, and collection. As a result, the key technical challenges in sugar beet harvesting mechanization have been effectively solved, and harvesting equipment technology has been improved.The main research contents and conclusions:(1) Through the research on China’s agronomic and the status of sugar beet harvesting equipment at home and abroad, the second harvesting patterns and processes was determined, the design scheme and route of traction type double row sugar beet harvest machine was proposed and the structure was designed, such as the adjustment of traction type cylinder, hydraulic-mechanical drive system, board-type throwing mechanism, rod-belt gripping delivery device and knapsack container. And the working principle and structural characteristics of sugar beet combine harvester were analyzed.(2) Through researching on sugar beet planting agronomic and root characteristics, the distribution in field, geometrical model and compression mechanical properties of sugar beet were obtained. According to the analysis of the influence factors of beet root pulling force, the optimal parameter combination was found out. This result will provide the reference to choose the key parameter of guiding system and digging equipment(3) Referencing the characteristic of digging harvest equipment in the domestic and overseas, determined the structure and working mechanism of digging equipment, built the relationship among the key parameters, constructed kinematics model and mechanics model of digging equipment, and checked the strength and deformation of device structure by the finite element analysis ANSYS. By the way of field experiment modeling, the relation between key parameters and performance indicators was established, and the optimal parameter combination was obtained by using optimization technique.(4) The structure and working mechanism of the guiding system were determined on the basis of analyzing the existing technology and the structure, and the relationship between the guiding device parameters and kinetic characteristics was analyzed. By field experiment and response surface optimization method, the mathematical model of the key parameters and guide effect indexes were established, the influence rule of parameters on the test index was studied, and the value range and the optimal combination of parameters were determined.(5) According to the existing transport and cleaning structure’s characteristics, the structure of the transport and cleaning device was determined, and the relationship and the scope of the parameters were decided by studying the working principles, parameters relationship and movement characteristics of the transport and cleaning device. Through researching on the movement characteristics of conveyor and interaction between chain and sprocket by the ADAMS simulation software, the effects of the key parameters in conveying processes of conveyor were analyzed, in order to find out the optimal parameter combination and the acceleration and the speed as beets leaving conveyer(6) By harvest field performance test, the imperfection of the prototype performance, working efficiency, suitability, reliability and others were improved and perfected. So the prototype has met the performance need of harvesting sugar beet.更多还原