【作者】 张学桐；

【导师】 曹利新；

【作者基本信息】 大连理工大学 ， 机械制造及其自动化， 2012， 硕士

【摘要】 船用螺旋桨属于典型的自由曲面类零件,其桨叶叶型复杂,制造精度及表面质量直接关系到舰船推进效率、振动、操纵性能及桨叶本身强度。近年来,加工船用螺旋桨往往使用五轴机床,而由于所用刀具和加工方法的限制,加工精度和效率仍不理想。此外,桨叶叶梢部分较薄,加工中易引起变形,这给加工系统的稳定性提出了更高的要求。因此,研究如何选择刀具类型和加工方法,保证切削加工的稳定性并提高加工精度和效率,具有极其重要的意义。本论文分析了船用螺旋桨桨叶的形成原理与特性,完成了桨叶切面数据到三维空间数据的转换。采用MATLAB语言编程,利用三次B样条插值理论完成了桨叶曲面的构造,进而完成了船用螺旋桨的造型,并基于MATLAB软件GUI平台设计了螺旋桨几何造型系统的图形用户界面。提出了大进给铣刀和基于大进给铣刀的密切加工曲面的方法,通过与环形刀的比较,分析了大进给铣刀的几何特性和切削受力特性,详细阐述了大进给铣刀进行曲面加工的密切刀位计算原理,并进一步分析了大进给铣刀采用密切法加工曲面的误差。结合桨叶曲面的微分几何特性和密切加工的条件,确定了大进给铣刀的刀具参数选择原则,并最终给出了大进给铣刀密切加工桨叶曲面的刀位计算实例。针对铸造毛坯螺旋桨,借助UG的多轴加工模块完成了其粗加工和仿真过程。针对桨毂通道的被加工区域提出了以插值思想为基础的刀具路径规划算法,之后给出了刀轴矢量的确定原则；此外,利用UG NX7.5版本的“mill multi blade”模块进行了桨毂的加工及仿真,将两种方法进行了对比,验证了本文所提算法的有效性。更多还原

【Abstract】 Marine propeller is a kind of typical free-form surface part, its blade is complexity, machining accuracy and surface quality are directly related to the efficiency of ship propulsion, vibration, manipulation performance and blade strength. With the development of multi-axis numerical control technology, marine propeller are usually machined by5-axis machine tool, however, due to the restriction of tools and machining methods, the machining accuracy and efficiency are still not ideal. In addition, the tip of the blade is always thinner, which lead to deformation easily, so there is a higher demand for the stability of the machining system. Therefore, research of selecting tool types and machining methods is vital to ensure the stability of machining system, improve machining accuracy and efficiency.In this thesis, principle of blade formation and characteristics of blade are firstly analysised,then the section data is transformated into three-dimensional data.Using MATLAB programming language, and based on cubic B-Spline interpolation theory, blade surface and propeller model are constructed, furthermore, on basis of MATLAB software GUI platform, the graphical user interface of propeller geometric modeling system is designed.High feed cutter (HFC) is introduced and osculating machining method is presented, comparted with fillet-end mill, geometric properties and cutting force characteristics of HFC are analysised, the fundamental of calculation of osculating cutter location is investigated in detail, after that, the osculating machining error by HFC is given. Combining the differential geometry features of blade surface and the osculating condition between cutter and blade, the selection principle of tool parameters is discussed, finally, the osculating tool position of blade surfaces machining by HFC are calculated.For casting blank, with the help of multi-axis machining module in UG, rough milling and simulation process of propeller are carried out. For the hub, a tool path planning method based on interpolation is studied, and then, the determination of tool axis vector is given. Moreover, by use of "mill_multi_blade" module in UG, the hub of propeller is machined and simulated, which verified the former tool path planning method.更多还原