定位误差的分析与计算

在对定位误差综合分析的基础上,归纳分析了单一基面定位误差的计算方式,并做了实例说明。     

定位误差的分析与计算

在对定位误差综合分析的基础上,归纳分析了单一基面定位误差的计算方式,并做了实例说明。     

定位误差的分析

主要介绍了机械加工过程中工件的安装夹紧误差的计算。通过实例讲解分析了解定位误差的确定方法。     

定位误差的简单计算法

定位误差的计算是夹具设计必须要做的一项工作 ,从明确相关概念、理清计算思路入手 ,介绍相对简单的定位误差的计算方法     

定位误差的尺寸链解法探讨

这里阐述了运用尺寸链原理计算定位误差的方法，给出了计算步骤，并通过实例说明了如何分析、计算定位误差。     

定位误差的简单计算方法

文中从明确相关概念、理清计算思路入手,在教学实践中,根据定位误差的合成方法,介绍了一种根据工序基准和定位接触点与定位基准的位置关系的计算定位误差的方法。     

基准不重合时定位误差的计算

根据尺寸链原理,用全微分方法进行基准不重合时定位误差的计算,概念清楚,方法简便.     

定位误差计算方法小结

定位误差（△D）是指用调整法进行加工时,由于工件在夹具中定位所引起的一种误差。定位误差包括基准不重合误差（△B）和基准位移误差（△Y）两项。     

不同思维角度下零件定位误差计算研究

零件的定位误差是由于工件在夹具(或机床)上定位不准确而引起的加工误差。该误差是确定零件正确定位后满足加工精度的前提保障。因此,掌握定位误差的计算是机械设计人员从事夹具设计的一项基本功,也是机械专业学习中的一个难点。通过几个实例从不同角度阐述零件定位误差的计算,为进一步深入研究定位误差计算提供参考和借鉴。     

定位误差分析中的概念误区

本文谅定位误差中的两个基本概念在国内现行的工艺及夹具设计专著中彼此矛盾的地方进行了分析，并提出了解决此问题的建议和设想。     

菲涅耳微透镜芯模表面形貌的检测及加工误差分析

采用扫描白光干涉法对菲涅耳微透镜芯模表面浮雕结构进行了检测,并对元件表面微观形貌进行了三维重建.根据其表面形貌数据,引入幅度参数表征法,分别计算出横向线宽误差以及样品的系统刻蚀深度误差和随机刻蚀深度误差等纵向加工偏差.通过表面高度分布的偏斜度、表面高度分布的峭度等参数获得了有关微芯模表面误差和缺陷的量化信息.实验研究表明,扫描白光干涉法能精确定量化表征微芯模表面形貌特征,这对探索适用于新型微光学器件表面三维形貌误差的无损检测评价方法具有实际意义.     

立式加工中心空间几何误差辨识解析及定位误差补偿研究

为大幅提升立式加工中心加工精度,满足当代数控机床对高精度的需求,针对立式加工中心3个运动轴,深入分析了其轴向运动空间几何误差,提出了可有效辨识运动轴轴向运动空间6项几何误差的辨识方法.建立了空间6项几何误差辨识模型,并针对关联轴联动垂直度误差进行了有效分析,建立了垂直度误差辨识解析模型.同时,针对3个独立运动轴轴向定位...     

Form error analysis of mould insert for large angle lens with ICP algorithm

Form measurement and form error analysis of high precision moulding lens of large angle have been immersed due to recent demands of some optical applications, such as mobile cellular phones with digital camera and daily disposable contact lens. The image dilation and distortion of measuring mould insert of soft contact lens needs to be compensated because of its steep-side features. This paper aims to utilize the iterative closest point (ICP) algorithm to stitch two curves which are measured on the different reference datum with a certain rotational angle. Measuring data is rotated back by a rotation matrix to improve the accuracy of ICP algorithm. Experiments have been conducted on a Mitutoyo profile analyzer with a Contracer CV-1000 and tip of radius 25 μm, angle 12° to measure a steel mould insert of soft contact lens. A sine bar and gauge blocks are used to measure twice on different sides of the reference datum with specified tilt angle. Results have demonstrated that the profile of a large angle lens can be reconstructed successfully and form error can then be calculated from the reconstructed profiles. Future work is to focus on exploring 3D measurement of non-symmetric lens.     

Efficient method of positioning error analysis for aeronautical thin-walled structures multi-state riveting

This paper deals with the inspection of highly reflective chrome-coated rings used in textile machinery using machine vision. These rings are mass produced in very large numbers, and the inspection was done manually using an optical microscope. Introduction of vision inspection using algorithms supplied by a commercial vendor had not helped the industry to achieve 100% quality inspection. In order to improve inspection speed and to ensure 100% quality inspection, it was absolutely essential to improve the complete inspection process, and it was also required to classify defective and non-defective components by a proper sorting algorithm. The effect of the curved, reflective nature of material and the real-time inspection make the imaging and defect detection and classification difficult. In the present study, four different algorithms based on Fourier filtering, auto-median, image convolution, and single-step thresholding approaches were used for defect detection, and then their performances were compared with reference to efficiency of defect classification and speed. The complete procedure, analysis, and the results of different image processing algorithms used in defect detection are reported in this paper.     

Dynamic positioning error analysis and modeling of CNC machine tool guideway system

Journal of Mechanical Science and Technology - The dynamic characteristics of the XY worktable are thoroughly analyzed in this study to accurately compensate the measurement errors of on-machine...     

夹具平面定位误差的连杆机构模型及其概率分析

研究了平面定位情况下的夹具定位误差通用分析方法.将加工表面、工序基准、定位基准和定位元件等决定定位误差的四个要素用直线、圆、圆弧和点等几何要素表示,并将四个要素之间的位置及其变动关系用平面连杆机构模型等价表示.通过研究采用机构的结构参数表示工件一夹具系统的所有工序信息及其内在联系的方法,建立了工件和夹具定位元件接触副与机构构件之间的映射关系,以及尺寸和形位公差的机构构件和运动副表示方法,从而实现了定位误差计算模型的自动建立.利用机构误差概率分析方法计算r夹具平面定位情况下的定位误差.     

板坯夹钳钳腿断裂的原因分析与处理对策

机械式板坯夹钳因其结构简单,使用和维护方便等原因在钢厂中得到广泛的使用,但如果对这种夹钳不能正确的操作也会出现被夹持物体脱落或夹具损坏变形。     

直放站装配夹具的设计

主要介绍直放站装配夹具的结构设计,该夹具在实际应用中提高了劳动生产率,降低了工人的劳动强度.     

摩擦片式攻螺纹夹具的设计

摩擦片式攻螺纹夹具可有效解决生产过程中丝锥强度低、切削条件差、丝锥易折断以及在加工盲孔和锻造件材料时损坏严重,在批量生产时效率不高的难题,提高了产品加工质量和经济效益.