Research on NC machining technology based on cutting tool creep-feed in feed direction

【中文文摘】通过对数控加工中存在的问题分析,提出了一种在数控加工中,刀具在被加工工件曲面上沿进给方向蠕动式切削加工的方法,通过刀具与工件时续分离和切削,改善了工艺系统的刚性,从而使工件的加工精度得到改善,并具体从被加工工件的几何形状、切削过程中刀具受力情况及切削区的切削热释放情况方面,分析了采用该方法对加工精度的改善情况。 【英文文摘】Based on analyzing problems that general NC machinining process exists, this paper proposes a machining method cutting tool creep-feed machining work piece in feed direction .When cutter is fed toward and away from work piece,it can improve the rigidity of mechanics system,so that machining precision is improved. Other advantages of this process include a superior surface finish,low tool pressure, and cutting heat released easily in the cutting section

Rapid & Flexible Punching and Shearing System Design for Agility Manufacturing

为了改造传统制造设备以实现快速柔性制造理念,设计了柔性冲裁模具系统的组成模块及其功能结构。详细阐述了其中图形处理模块的自动数控编程设计方法。通过分析DXF图形文件结构,提取数控加工所需的数据信息,再根据现场加工工艺要求,进一步对图形数据作分类排序处理,然后自动生成加工的数控代码文件。系统为了对生成的NC代码进行校验,设计了具有加工动态仿真功能的模块,提高了加工效率和加工质量。Agility Manufacturing needs a rapid and flexible manufacturing cell.In order to rebuild traditional equipment to respond rapid and flexible manufacturing,a flexible mould system and its components for metal sheet punching and shearing was proposed.Technique of NC programmed in graphics processing system was particular explained.Based on analyzing the structure of DXF files,the data information requested for NC machining was gotten.According to punching technics conditions in the workshop,the data was classified and ordered again,and NC codes were automatically created.A plane dynamic model was given to simulate machining process and verify the NC code,which improves machining efficiency and quality

Study of Visual Servoing for Microassembly Based on Focus of Microscope

【中文文摘】利用显微镜聚焦理论,沿显微镜光轴方向移动物体,不断计算图像的灰度变化之和,可判断出物体沿光轴的坐标,将这一坐标集成在伺服控制方程中,可完成立体视觉跟踪。这样,采用单目视觉系统就可以获得物体的三维坐标,避免了双目立体视觉系统的复杂结构。为了提高系统图像处理速度,利用卡尔曼滤波器对跟踪的特征点进行预测,并用窗口处理技术减小图像处理区域。实验和仿真结果表明,上述方法可完成复杂微装配的视觉跟踪,系统有好的实时性。 【英文文摘】When the object is moved along optical axis of microscope and the variational gray-level of the image is added at the same time,using focus theory,the coordinate of object is obtained along optical axis of microscope,the coordinate of object can be used in servo control equation to finish three dimension vision tracking of microassembly.In this way,when single vision system is used,the three dimension coordinate of object can be obtained and complicated stereo vision system can be avoided.In order to improve the speed of image processing, the Kalman filter is used to predict the next place of tracked point. The results on experimentation and simulation show that complex microassembly task can be finished and the speed of image processing can be improved国家自然基金(50275078)资助项

Theoretical Model of Maglev Micro Assembly System and Its Realization Technology

针对现有微装配系统存在的问题,给出了一种新的理论模型;将微产品装配离散化,便于建立标准化、模块化的实用微装配系统.该模型为灵巧加工及CIMS微系统打下了基础.利用磁悬浮平台代替粗/细运动平台传送装配子单元;同时,也利用它作为微装配平台,在一个运动平台实现了粗/细运动;没有导线与运动平台相连,实现了平台的长距离运动.巧妙地利用平台运动实现线激光对微装配环境的扫描,获取微装配环境的三维信息.将全局/局部视觉系统分离,增加了操作空间.采用两种模型对磁悬浮系统进行控制,满足了粗/细运动精度.采用该理论模型可以简化系统的结构,提高装配效率.A theoretical model is presented which adopts maglev system to decompound complex problems in micro assembly and makes the system simple. This theoretical model is also convenient to constitute a standardized, modularized and practicable micro assembly system, and, furthermore, establish foundation of agile manufacture and CIMS microsystem. In the theoretical model, maglev platform is used to replace coarse-fine platform to transfer micro assembly subsystem and also used to assemble micropart, connect the platform without wire to realize a long distance movement. Line laser system scan micro assembly circumstance in the process of maglev platform movement and 3D data of microassembly is acquired. Global-local vision system are separated to widen operation space. In maglev system control, two types of dynamics model are used to satisfy the precision of coarse-fine movement. The theoretical model can reduce assembly cost of microparts and improve assembly efficiency.国家自然科学基金资助项目(50675184)

Transform Principle of Moving Parameters in Different CNC Five-Axis Tool Grinding Machines

【中文文摘】详细分析了CNC五轴立式砂轮平动工具磨床 (P型 )和砂轮摆动工具磨床 (B型 )的运动形式及其加工原理 ,并将之与传统机床进行了比较 ;从所要求的同一个几何参数刀具具有相同的几何本质出发 ,给出了P型和B型 2种类型CNC工具磨床的内在运动参数的转换关系。研究阐明了在刀具磨削成形的过程中 ,控制每个瞬时砂轮几何体和工件几何体在空间的相对位姿和相对运动趋势是精确成形的关键。 【英文文摘】This paper analyses the movement format and the machining principle of the CNC five axis tool grinding machines, the grinding wheel translating (P-type) and grinding wheel wiggling (B-type) types. In addition, this paper compares the characteristics of the P-type and B-type machines with the traditional tool grinding machine. Based on the fact that the cutter tools with the same type of geometrical characteristics share the same the geometrical essence, a transformation relationship in the inherent movement indexes between P-type and B-type of CNC tool grinding machines is formulated. Our research work points out the key controlling factors to approach the precision in the processes of grinding and shaping. The key factors in every moment are the relative spatial positions and the corresponding moving tendency between the grinding wheel and the cut piece

沥青原料对沥青基碳纤维结构与性能的影响

以中间相萘沥青(AR树脂)和各向同性煤沥青(ICP)为原料,系统研究了沥青原料性质与由其制备的碳纤维结构、性能之间的关系。研究表明,AR树脂中的一维有序中间相结构在纺丝中被拉伸,形成不同中间相间的界面,成为应力集中区,在后续碳化过程因应力释放导致纤维开裂而损害其力学性能;而ICP沥青基本为无定形相结构,在纺丝过程中无明显的择优取向,碳化过程石墨化程度低,故其所成的碳纤维无应力集中和开裂问题,但也正是这无定形结构,使其最终力学性能也较差。以上结果说明,原料的性质可以"遗传"到沥青基碳纤维中。因此,改变沥青原料的性质是改善沥青基碳纤维结构和性能的有效途径之一

同步氢化/热缩聚法制备中间相沥青

通过同步氢化/热缩聚反应,制得中间相沥青(MP);重点研究了四氢萘(THN)用量对MP性质的影响。研究表明THN增加,MP的软化点(SP)随之降低,H/C随之提高,不溶分随之减少;偏振光显微镜研究表明THN用量少于8%时,MP的形貌为分布不均的各向异性与各向同性两种沥青的混合物;而随着THN的增加,各向异性沥青逐渐趋于以中间相小球形态,并且较为均匀地分布到各向同性沥青基质之中。MP经保温处理后,纺丝性能得到改善,最终制得横截面呈无规结构的沥青基碳纤维

沥青原料对沥青基碳纤维结构与性能的影响

以中间相萘沥青(AR树脂)和各向同性煤沥青(ICP)为原料,系统研究了沥青原料性质与由其制备的碳纤维结构、性能之间的关系。研究表明,AR树脂中的一维有序中间相结构在纺丝中被拉伸,形成不同中间相间的界面,成为应力集中区,在后续碳化过程因应力释放导致纤维开裂而损害其力学性能;而ICP沥青基本为无定形相结构,在纺丝过程中无明显的择优取向,碳化过程石墨化程度低,故其所成的碳纤维无应力集中和开裂问题,但也正是这无定形结构,使其最终力学性能也较差。以上结果说明,原料的性质可以"遗传"到沥青基碳纤维中。因此,改变沥青原料的性质是改善沥青基碳纤维结构和性能的有效途径之一

The development of online detecting system of five-axis CNC grinding machine for indexable insert

五轴可转位刀片磨床具有高速、高精的特点,为了使所磨的刀片符合精度要求,需要针对刀片的尺寸开发一种在线检测系统。本文所介绍的在线检测系统主要由两方面构成:一是在磨床数控系统中将测头伸缩时发出的电压信号转换为测量值;二是建立刀片尺寸的加工模型。在线检测系统通过调用系统的测量宏程序,获取刀片测量值,将此测量值输入到加工模型中,得到所加工刀片的指导尺寸。通过实验,得到了刀片的指导尺寸和测量时间,验证了此在线检测系统是可行并且可靠的。The five-axis CNC grinder of indexable insert is characterized by high-speed and high-precision.,in order to meet the accuracy requirements of grinding blades, needed an online detection system developed for the size of the blade.The online detection system described in this article consists of two aspects: First, the voltage signal that when the probe telescopics will be converted to the measured value; Second, establishing the process model of the blade size.The online detection system will get the blade measurements by calling the measure macro, then the measured value input into the process model, obtaining the guidance blade size.Through the experiment, verifying this online detection system is feasible and reliable by the obtained guidance blade size and the measuring time.国家“高档数控机床与基础制造装备”科技重大专项资助(2010ZX04001-162

Automatic Dressing and Compensation Method of Diamond Wheel in CNC Grinding Machine

金刚石砂轮在使用过程中会磨损、钝化,影响磨削性能,需要定期修整。本文介绍砂轮修整原理,并给出一种砂轮修整的全自动控制方法和补偿方法。通过长时间连续自动运行,验证了该方法的实际应用效果。After a period of using,the diamond grinding wheel will be worn and blunted,which can seriously affect the grinding performance.So,the diamond grinding wheel requires dressing regularly.The article introduces the principle and methods of dressing and gives an automatic control and compensation method.Through a long continuous running,the result of practical application of this method has been verified.国家“高档数控机床与基础制造装备”科技重大专项(2010ZX04001-162