Development of meso-scale milling machine tool and its performance analysis

To overcome the shortcomings of current technologies for meso-scale manufacturing such as MEMS and ultra precision machining, this paper focuses on the investigations on the meso milling process with a miniaturized machine tool. First, the related technologies for the process mechanism studies are investigated based on the analysis of the characteristics of the meso milling process. An overview of the key issues is presented and research approaches are also proposed. Then, a meso-scale milling machine tool system is developed. The subsystems and their specifications are described in detail. Finally, some tests are conducted to evaluate the performance of the system. These tests consist of precision measurement of the positioning subsystem, the test for machining precision evaluation, and the experiments for machining mechanical parts with complex features. Through test analysis, the meso milling process with a miniaturized machine tool is proved to be feasible and applicable for meso manufacturing.     

大口径光学元件高精度平面磨床加工系统研究

以实现高精度、高效率、高自动化程度加工为目的,基于高精度平面磨床MGK7160的加工系统,详细分析了加工规划控制、计算机辅助制造软件系统开发、砂轮修整及动平衡、在位测量等关键配套工艺技术。在已有设备及配套工艺基础上利用400#粒度金刚石圆弧砂轮,实现口径400mm×400mm平面光学元件的加工,获得了较好的加工精度,验证了机床及加工技术系统的可靠性。     

Fabrication of Microlens Array and Its Application:A Review

Microlens arrays are the key component in the next generation of 3D imaging system, for it exhibits some good optical properties such as extremely large field of view angles, low aberration and distortion, high temporal resolution and infinite depth of field. Although many fabrication methods or processes are proposed for manufacturing such precision component, however, those methods still need to be improved. In this review, those fabrication methods are categorized into direct and indirect method and compared in detail. Two main challenges in manufacturing microlens array are identified: how to obtain a microlens array with good uniformity in a large area and how to produce the microlens array on a curved surface? In order to effectively achieve control of the geometry of a microlens,indirect methods involving the use of 3D molds and replication technologies are suggested. Further development of ultraprecision machining technology is needed to reduce the surface fluctuation by considering the dynamics of machine tool in tool path planning. Finally, the challenges and opportunities of manufacturing microlens array in industry and academic research are discussed and several principle conclusions are drawn.     

雕塑曲面体混流式叶片的多轴联动数控加工编程技术

转轮叶片是水轮机能量转换的关键部件,也是最难加工的零件,目前多轴联动数控加工是解决该类大型雕塑曲面零件最有效的加工方法。多轴联动数控加工编程则是实现其高精度和高效率加工的最重要环节。本文介绍混流式水轮机叶片五轴联动数控加工大型雕塑曲面编程中涉及到转轮叶片三维造型、刀位轨迹计算、切削仿真、机床运动碰撞仿真、后置变换等关键技术。通过对这些技术的链接和研究,开发实现了大型叶片的多轴联动加工。     

薄壁零件高速铣削加工技术研究

薄壁零件高速铣削加工具有传统铣削加工无可比拟的优势,是薄壁零件切削加工的发展方向。本文分析和讨论了薄壁零件高速铣削加工过程中涉及到的加工工艺、切削刀具、数控编程以及装夹方式等关键技术问题,介绍了提高薄壁零件加工精度、表面质量和加工效率的技术方法和工艺措施。     

介观尺度微型铣床开发及性能试验

针对微机电系统(Microeletro mechanical system, MEMS)技术和超精密加工技术局限,开展面向介观尺度微细铣削技术的研究。首先根据介观尺度铣削的加工特点,对其机理研究的关键问题进行详细的分析和讨论,提出微细铣削理论的研究重点及研究方法。然后在分析微细铣削成形条件和加工要求的基础上,开发微型铣床系统,并对系统各组成子系统及性能指标进行描述。最后开展机床加工性能评估试验,通过精度测量、误差分析和误差补偿提高工作台的定位精度达到1.62 μm,采用直径0.127 mm铣刀开展微铣削试验,通过表面粗糙度测量和同心圆切削试验评估机床的加工精度,在此基础上通过复杂零件加工实例进一步说明机床的加工能力,论证小型化机床加工技术的可行性和实用性。     

Dynamic wireless passive strain measurement in CNC turning using surface acoustic wave sensors

Wireless, passive and dynamic surface acoustic wave (SAW) strain sensors are especially advantageous in applications with harsh environments where complex force measurements are required. High frequency multiple axis force measurement during machining processes typically requires state-of-the-art piezoelectric dynamometer technologies. Integrating dynamometers and their associated measurement chains into the machining environment typically requires significant modification to the machine structure. In this paper, SAW sensors were developed for process monitoring operations. Single-axis continuous and interrupted cutting investigations were carried out using the SAW technology installed on cutting tool holders demonstrating high dynamic bandwidth strain measurement. SAW dual-axis oblique cutting measurements were carried out where four SAW sensors were set up as two differential pairs each measuring a single axis of applied force. Improvements in sensitivity and cross-talk compensation has been realised. High-frequency wireless passive realtime process signals are presented from a passive wireless SAW force measurement system successfully integrated into an LT15 Okuma machining centre. The paper aims to present wireless passive SAW technology as a potentially platform changing approach for process and tool condition monitoring applications in the future.     

Precision design for machine tool based on error prediction

Digitization precision analysis is an important tool to ensure the design precision of machine tool currently.The correlative research about precision modeling and analysis mainly focuses on the geometry precision and motion precision of machine tool,and the forming motion precision of workpiece surface.For the machine tool with complex forming motion,there is not accurate corresponding relationship between the existing criterion on precision design and the machining precision of workpiece.Therefore,a design scheme on machine tool precision based on error prediction is proposed,which is divided into two-stage digitization precision analysis crucially.The first stage aims at the technology system to complete the precision distribution and inspection from the workpiece to various component parts of technology system and achieve the total output precision of machine tool under the specified machining precision;the second stage aims at the machine tool system to complete the precision distribution and inspection from the output precision of machine tool to the machine tool components.This article serves YK3610 gear hobber as the example to describe the error model of two systems and basic application method,and the practical cutting precision of this machine tool achieves to 5-4-4 grade.The proposed method can provide reliable guidance to the precision design of machine tool with complex forming motion.     

现代高速切削与工具技术

高速加工和高效加工是目前获得高效机械加工生产率的重要手段，它在航空和航天产品的零件制造、模具制造以及汽车零部件制造等领域有较大的需求。机床采用高速传动技术、高速进给技术、高速切削刀具，配以大功率或大扭矩主轴系统以及复合加工技术，可实现高速加工与高效加工。近几年我国在机床高速化技术方面的研究开发取得了长足进步，并开发出相应的主机产品，为我国数控机床向高速、高效和精密方向发展奠定了基础。     

CIMT’97主要展品的技术特点综述

两年一度的中国国际机床展览会是国际机床界和我国机械制造业的一件盛事。第五届中国国际机床展览会(CIMT’97)又一次荟萃了国内、外各机床厂及相关配套件厂和工具厂的精华,既可看到一些名牌企业享有盛名的产品,也会发现一些脱颖而出的新秀企业所展示的精品。从展览会上我们能深刻地领会到机床工具行业的发展动向,也能生动地观察到琳琅满目的新产品和新结构。从中既反映了丰富多采的世界先进实用制造技术和最新制造技术,也展示了中国机床工具行业通过“三大战役”在增强开发能力和竞争实力方面所取得的可喜的巨大进步。     

超精密加工技术研究现状及发展趋势

超精密加工是多种技术综合的一种加工技术,是获得高形状精度、表面精度和表面完整性的必要手段。根据当前国内外超精密加工技术的发展状况,对超精密切削、磨削、研磨以及超精密特种加工及复合加工技术进行综述,简单地对超精密加工的发展趋势进行预测。     

电化学机械精准光整加工技术研究

介绍了该研究组近年来在电化学机械精准光整加工技术研究方面的工作进展情况,包括：光整过程中同时完成形状成形的光整与成形复合加工技术;同时改善零件精密度和表面形貌的跨尺度精确成形加工技术;保证精密度条件下改善表面形貌的自由曲面零件手持式工具光整加工技术。研究工作表明：通过合理优化电化学机械加工工艺系统结构和参数,对于齿轮、轴承等规则表面零件,可以实现同时改善零件精度和表面几何形貌;对于非规则表面零件,可以在保证零件精密度条件下改善零件表面几何形貌。     

在线测量技术在数控加工中的应用

论述了精密测量技术的发展和数控技术的特点，介绍一种新型的在位检测系统，指出在线测量应用于数控技术的可行性及其发展前景。     

Development of meso-scale milling machine tool and its performance analysis

To overcome the shortcomings of current technologies for meso-scale manufacturing such as MEMS and ultra precision machining, this paper focuses on the investigations on the meso milling process with a miniaturized machine tool. First, the related technologies for the process mechanism studies are investigated based on the analysis of the characteristics of the meso milling process. An overview of the key issues is presented and research approaches are also proposed. Then, a mesoscale milling machine tool system is developed. The subsystems and their specifications are described in detail. Finally, some tests are conducted to evaluate the performance of the system. These tests consist of precision measurement of the positioning subsystem, the test for machining precision evaluation, and the experiments for machining mechanical parts with complex features. Through test analysis, the meso milling process with a miniaturized machine tool is proved to be feasible and applicable for meso manufacturing. __________ Translated from Chinese Journal of Mechanical Engineering, 2006, 42(11): 162–167 [译自: 机械工程学报]     

软体磨具新技术

零件曲表面的磨光,抛光技术是精密加工技术领域的难题,传统的磨具难以直接对不规则的曲面进行加工。作者研究的软磨具,是一种体内均匀含磨料的新型高分子复合材料、磨料和抛光粉为加工要素,聚氨酯基网链状高分子材料为连接剂并为抛光要素。新型软磨具为三维柔软的弹性体,能适应任意曲率的零件（金属或非金属）表面的磨光和抛光要求。本文包括新型软磨具的生成理论,制造技术和曲面零件抛光的工艺性能试验研究。     

加工中心的刀具监控技术发展应用浅谈

高速加工是现代制造技术核心。加工过程表现出的安全要求更为迫切。刀具监控正在发展成为现代制造理论的支撑技术之一；正是高速加工安全问题对刀具实时监控技术的这种需求。促进了该顶技术的发展和成熟并走向实用化。     

A smart machine supervisory system framework

Machine tools and machining systems have gone through significant improvements in the past several decades. Recent advance in information technology made it possible to collect and analyze a large amount of data in real time. This brings about the concept of a smart machine tool, enabled by process monitoring and control technologies, to produce the first and all subsequent parts correctly. This paper presents a system framework for a smart machine supervisory system. The supervisory system integrates individual technologies and makes overall intelligent decisions to improve machining performance. The communication mechanism of the supervisory system is discussed in detail. Its decision-making mechanism is illustrated through an example that integrates process planning, health maintenance, and tool condition monitoring.     

超精密测量关键技术的研究动态

超精密测量是超精密加工中的重要一环,目前其研究的内容主要涉及光干涉技术、电学测量技术以及扫描探针技术等几个方面,本文主要介绍了几种测量技术的工作原理、设备技术等方面的研究及进展情况.     

复杂曲面高效铣削加工的刀具尺寸优选

刀具尺寸是影响复杂曲面数控加工质量和效率的重要因素,基于刀具尺寸与曲面加工质量和效率的函数关系,给出了保证加工曲面精确性的最优小刀具选择方法,建立了以效率最高为目标的合理大刀具尺寸优选算法,并针对几何特征复杂的曲面,提出了以刀具加工有效面积比值为参考的刀具组合选择方法。应用实例表明:该刀具尺寸优选策略在充分保证复杂曲面加工质量的前提下,能有效提高其整体加工效率。     

机器人复合加工模具曲面的干涉回避与质量控制

提出一种由机器人和超声电火花复合研磨机等组成的自动研磨加工系统，对在模具曲面加工过程中出现的工具与工件之间可能产生的局部干涉现象进行了研究，通过干涉回避技术建立复合精加工表面质量的控制模型，并在试验中证实了理论的正确性。