【作者】 王金生；

【导师】 彭伟； 翁泽宇；

【作者基本信息】 浙江工业大学 ， 机械制造及其自动化， 2004， 硕士

【摘要】 随着机床向高速度、高精度方向的迅速发展，对机床的加工精度和可靠性提出了更高的要求，机床的热态特性成为人们关注和研究的热点之一。在机械加工中，工艺系统在各种热源(摩擦热、切削热、环境温度、热辐射等)的作用下，产生温度场，致使机床、刀具、工件、夹具等产生热变形，从而影响工件与刀具间的相对位移，造成加工误差，进而影响零件的加工精度。根据调查统计表明，在精密加工中，热变形引起的制造误差，占总制造误差的40％～70％。因此，如何减少热变形，提高加工精度，是机床设计中非常棘手和重要的问题。本课题结合浙江省重大科技招标资助项目(大型高效数控模具加工机床关键技术研究)，在设计阶段，使用有限元方法，对XK717数控铣床进行热特性研究，并根据研究计算的结果进行评价，最终达到设计目标。内容如下： 第一章，论述了工艺系统的热源、改善机床热变形的对策以及主轴系统热特性的研究，并介绍了本文的课题背景，概述了本文的主要工作。 第二章介绍了热传导和热弹塑性基础理论知识，总结了温度场和热弹性的有限元分析理论。 第三章着重分析了数控铣床热边界条件的模型，以及讨论了数控铣床整机热特性和主轴系统热特性分析的过程与方法。 第四章对XK7 17数控铣床进行整机热特性分析，并与现有XKS 10数控铣床的分析结果进行比较，从而为进一步采取措施，改善机床热特性提供了依据。 第五章建立了XK7 17数控铣床主轴及主轴箱的三维有限元模型，结合普通水箱进行冷却时冷却水温升的数学模型，对带有冷却套冷却的铣床主轴系统进行热特性分析，得出了各种参数(如冷却泵的流量、水箱的大小、散热状况及冷却水的温度)对主轴热特性的影响规律;并提出了对主轴冷却套的布局进行改进的想法，从而为数控铣床的设计提供了理论依据。全文的研究结果进行了总结并对进一步工作进行了展望。更多还原

【Abstract】 With the development of machine tools in higher speed and higher precision, the thermal characteristic of machine tools is becoming more and more important. Many kinds of the heat sources (frictional heat, cutting heat, ambient temperature, etc) in machining system produce a kind of temperature distribution. This temperature distribution induces thermal deformation between machine tools, tool, work-piece and work holding fixture. This deformation affects the relative displacement between the work piece and the cutter, causes the manufacturing errors, and influences the machining accuracy of the work-piece. From J. Peclenik’s investigation, thermal errors accounts for 40%-70% in the precision machining. Therefore, it is very important to reduce thermal deformation and improve the machining accuracy in the design of machine tools, hi this paper, thermal characteristics of XK717 CNC milling machine are analyzed by using the finite element method, supported by a key project of Zhejiang Province.In chapter 1, heat sources in machining system, countermeasure of improving thermal deformation and the study of thermal behavior on the spindle system have been summarized. The background of the project and main contents of this paper have been introduced.In chapter 2, heat conduction and thermal deformation theory are introduced. And then, the finite element method about temperature field and thermal deformation is summarized.In chapter 3, empirical model of the thermal boundary conditions is analyzed onthe CNC milling machine. Process and method of thermal behaviors is discussed on XK717 CNC milling machine and its spindle system.In chapter 4, thermal characteristics of XK717 CNC milling machine are simulated and the result provides the basis to improve thermal behaviors for design of CNC milling machines compared with XK510 CNC milling machine.In chapter 5, thermal characteristics of spindle system with cooling jacket are analyzed on XK717 CNC milling machine by combining 3D finite element model with the temperature model of cooling water between spindle system and water tank. The effect factors to thermal behavior of the main spindle system are studied by analyzing both cooling parameters and structure.Finally, the main conclusions and prospects for the future research are presented.更多还原