【作者】 渠聚鑫；

【导师】 刘明刚；

【作者基本信息】 中国林业科学研究院 ， 材料加工工程， 2009， 硕士

【摘要】 提高森林覆盖率,改善生态环境,必须大力开展植树造林。只有机械化才能最大限度地提高生产率,降低生产成本,实现高效造林。挖坑机就是重要的机械化造林设备之一。针对我国林区复杂多变的林地条件和土壤类型,研发不同类型的挖坑机。本文研究的挖坑机是针对我国南方丘陵、山地条件挖坑植树的需要,并运用现代设计方法、设计思想,创新研制出的高性能、低成本、高效率新型自走式是植树挖坑机。新型自走式植树挖坑机首次将助力行走系统与挖坑机工作钻头集于一体,利用张紧离合操作方式控制行进和作业,切换方便。能够适应我国南方坡度小于25°的山地环境,本设计中选用的汽油发动机功率为6.5HP,设计挖坑直径在150mm到350mm之间,新型自走式植树挖坑机体积小,重量轻,符合市场需求。本文首先介绍了国内外几种植树挖坑机,并对这些设备进行了简单分类。同时,对挖坑机的发展前景和方向做了简单的讨论。第二,定性地分析了自走式挖坑机的总体设计原则,对各主要部件的选型作了探讨和研究。其中包括对万向节轴、软轴、皮带轮、锥齿轮减速器、张紧离合操作系统等的结构计算和参数确定。第三,分析研究了钻头入土阻力、钻头合理转速、螺旋翼片升角等钻头的结构及运动参数。建立了钻头的三维模拟仿真模型,通过应用分析软件Pro/Mechanical对挖坑机钻头主轴进行了结构应力分析,依据最优化原理给出了钻头主轴的优化设计数学模型并进行优化运算,最终得到设计范围内的最优解。同时建立了刀片切土模型,通过分析得出了刀片切土角与安装角的最佳选取范围。第四,本文对挖坑机的传动机构和行走系统进行了运动模拟分析,得出钻尖的位移变化情况,以及万向节轴、行走轮轴在设计时段内每一时刻的位移、角速度、角加速度等的变化,为构件的设计和动力的选择提供了理论支持。最后,对植树挖坑机的生态效益、社会效益和经济效益进行了综合分析。更多还原

【Abstract】 To increase the forest coverage and improve the ecological environment, we must carry out afforestation energetically. Only the mechanization can further improve the productivity, lower the production cost, realize high-efficiency forestation. A earth auger is important equipment, and different kinds of earth augers are designed for differernt landform. In this paper, a new self-propelled earth auger is studied for the need of tree-planting in southward and modern design methods are applied in exploiting powerful, low-cost and high-efficiency earth augers.The new self-proprelled tree planting earth auger collects the running system and working part in one body at first time. To control running and working through making use of tension pulley clutch, and switch easily. Adapt to hilly conutry in Southern China whose grade is less than 25°. Selection of the design power of the gasoline engine 6.5HP, designed for digging in diameter between 150mm to 350mm. The new self-propelled earth auger who has small size, light weight, will accord with the demand of market.At the beginning of this paper, some kinds of domestic and international earth augers are introduced and some views on the development trend of earth augers are provided. Secondly, the general design principle of the new self-propelled earth auger is analyzed qualitatively and the choice types of each part is discussed, such as structural calculation or parameter determinaion of universal coupling, soft-shaft, bell wheel, bevel gear reducer, clutch of tension pulley, etc. A three-dimension model of the auger is established, using Pro/Mechanical to make sturctural stress analysis of auger’s principal axis, giving the optimization design model of the principal axis according to optimization principle and then the optimization dimension in design range is obtained. And, soil cutting model of earth auger’s blades is estabished, which shows reasonable selection range of cut-in angles and installation angles of blades. Then, the kinematice simulation analysis of the transmission mechanism and the running system is made, the change of drill tip’s displacement, angular velocity, augular acceleration of universal coupling and running axle at each designed time are obtained, offering theoretical assistance for the design of parts and choice of power. Finally, the zoology benefits, society benefits and economy benefits of the digging machine are analyzed.更多还原