无动力手推式割草机设计目 录摘要 ....................................................................4Abstract ...............................................................5第一章 绪论 ............................................................61.1 选题的背景和目的.....................................................61.2 无动力手推式割草机国外的进展现状....................................61.3 割草机的概述........................................................81.3.1 割草机的分类.....................................................81.3.2 手推式割草机的结构特点..........................................101.3.3 如何安全操作草坪割草机..........................................11第二章 割草机总体方案的设计..........................................12第三章 割草机零部件的设计............................................153.1 割草机行走轮的设计.................................................153.1.1 材料选择的依据..................................................173.2 凸轮的设计.........................................................173.2.1 凸轮材料的选择..................................................173.3 切割器的选择........................................................183.3.1 切割器材料的选择................................................203.4 轴的设计............................................................233.4.1 轴的概述........................................................233.4.2 轴的设计........................................................233.4.3 轴的材料选择....................................................233.5 轴承的选择..........................................................243.5.1 轴承的载荷......................................................243.5.2 球轴承的特点....................................................243.5.3 轴承的转速......................................................243.6 键的选择...........................................................253.7 平行四杆机构的设计...................................
