【作者】 齐爽；

【导师】 邹青； 赵宏伟；

【作者基本信息】 吉林大学 ， 机械工程， 2011， 硕士

【摘要】 超精密机床进给是保证加工质量和加工效率的关键,为了适应超精密加工技术的发展,满足超精密加工机床高效率、高精度的要求,本文进行了超精密机床滚珠丝杠配合压电补偿单元共同作用的Z轴进给模式研究,并对与压电叠堆相配合的柔性铰链进行了结构设计和仿真分析,为压电驱动单元力和位移的输出提供了可靠的保障,该设计思路开拓了一种新型的在垂直方向上利用压电驱动单元作机床微进给补偿机构的设计理念。本论文主要完成了以下几个方面的内容：(1)概述超精密加工、超精密机床、机床驱动方法(包括传统步进电机、滚动导轨、静压导轨、直线电机以及新型智能材料元件)的发展历史与现状,系统性地综述了压电驱动的发展历程及其应用于驱动领域特有的优势,阐明了本论文的主要研究内容和意义。(2)介绍压电效应的基本原理并列出压电叠堆的重要特性指标,从静力学和动力学两个方面对压电驱动力学特性进行公式推导,为下一步柔性机构设计和仿真分析奠定了坚实的理论基础。(3)通过对压电微进给驱动器的方案论证,最终确定超精密机床的整体框架结构,并根据加工要求对各关键元件进行选型,主要针对压电补偿驱动单元进行结构设计。(4)通过仿真分析选择合适的柔性铰链类型,通过公式推导得出直角柔性机构的力学特性。根据机床的设计要求对柔性铰链进行结构设计,并运用ANSYS软件对柔性铰链应力、应变、输出位移以及模态进行仿真分析,为下一步结构优化打下基础。(5)利用正交试验法对所设计的柔性铰链模型进行结构优化,按照所需试验指标(即最大应力、最大应变和一阶固有频率值)设定一个5因素4水平的正交表,通过对16组仿真分析结果进行极差分析,得出最优解。(6)利用ANSYS软件对最优柔性结构再次进行静力分析与模态分析,验证最优解在力学性能与动态特性上具有最优效应。采用线切割技术对柔性机构进行实际加工,利用激光位移传感器对压电驱动单元的线性度、最小补偿量和稳定性进行检测,并得出相关结论。更多还原

【Abstract】 The feeding of ultra-precision machine is the key to the quality and the efficiency of the machining. In order to adapt to the development of ultra-precision processing technology and meet the high efficiency and precision requirements of the ultra-precision machine, the Z-axis feed mode of the ultra-precision machine tools with the ball screw and the micro piezoelectric compensation is researched and the flexible hinge structure associated with the piezoelectric structure is designed and analyzed in this topic. They provide reliable output protection of the force and the displacement for the piezoelectric actuators. This design opens up a new way that the piezoelectric actuator is used for the Micro-feed mechanism of machine tools which request low orders of magnitude in vertical direction. The paper’s primary coverage is as follows:(1) Outlines the developing history and present situation of the Ultra Precision Machining, the Ultra Precision Machine Tools and the Machine Driven Approach (including stepping motor, rolling guide, hydrostatic sideways, linear electric motors and new intelligent material). The developing course and the unique advantages that applied to in the field driven of piezoelectric driven are systematically summarized. Then the main research contents of this paper are illustrated.(2)Introduces the basic principle of the piezoelectric effect and enumerate the important characteristic indexes of the piezoelectric stack. Mechanical characteristics of piezoelectric driven is derived from the two aspects of statics and dynamics. They lay a solid theoretical basis for the next step of flexible mechanism design and simulation analysis.(3) Determines the holistic frame construction of the ultra-precision machine tools finally based on argumentation of the piezoelectric micro-feed actuator project, and then the key components are selected according to the requirements of processing. The structure of piezoelectric actuator for compensation is mainly designed.(4)Selects appropriate type of flexible hinge through simulation analysis, and the mechanical characteristics of right-angle flexible hinge are derived. Designs the structure of the flexible hinge according to the design requirements of the machine tools, and analyzes the kinematics and the modal of the flexible hinge with the ANSYS software in order to lay a foundation for the further optimization.(5)Analyzes the structure of the flexible hinge model by the method of the Orthogonal Test, and then designs an orthogonal table which has five factors and four levels in accordance with the necessary test index (maximum stress, maximum strain and first-order natural frequency), gets the optimal solution based on the analysis of range about the sixteen groups of analytical result.(6)And then analyzes the kinematics and the modal of the flexible hinge with the ANSYS software again in order to verify the optimal solution with optimal effect in mechanics performance and dynamic characteristics. Actually processes the flexible mechanism with Wire-cutting technology, tests the linearity, resolution and stability of the piezoelectric drive unit with the laser displacement sensor and makes relevant conclusions.更多还原