成形车刀加工圆锥面时双曲线误差的定量分析

成形车刀加工圆锥面时双曲线误差的定量分析军需工业高等专科学校（邢台０５４３３５）谷群广，杨烁在实际生产中，当用成形车刀加工圆锥面时，经常发现加工后所得到的不是圆锥面，而是如图习所示的单叶双曲回转面，这种加工误差称为“双曲线误差”。产生这种误差的原因如...     

棱体成形车刀简易精确设计

棱体成形车刀是一种 生产率高、加工质量稳定的专用刀具,但其设计、计算却比较麻烦。通常介绍的成形车刀设计法是按近似方法设计的,因此其突出间题是加工锥体部分存在较大双曲线误差。     

成形车刀加工锥体工件产生的双曲线误差的修正

用普通成形车刀加工锥体工件要产生双曲线误差。实践证明,双曲线误差往往使加工后的工件超差。目前虽有几种减小双曲线误差的方法,但不理想,因各种方法对圆体成形车刀自身造成双曲线误差都不能减小,而自身造成误差一般占整个双曲线误差的95％。有必要寻求一种新的方法减小这种误差。双曲线误差产生的原因是因为用带有前角的普通成形车刀加工锥体时,前刀面与锥体表面的交线是一条外凸的双曲线,要加工     

棱体成形车刀的精确设计及圆锥体零件的成形加工

针对棱体成形车刀的某些不足，对侧置及径向棱体成形车刀的精确设计公式进行了推导，并提出了一种简便的加工圆锥形零件成形车刀的精确设计方法。     

用成形车刀加工圆锥面双曲线误差分析及其减小措施

分析了用常规方法设计、制造的成形车刀加工团推面时产生的双曲线误差,导出了用棱体和圆体成形车刀加工时误差表达式,讨论了工件和刀具雏角、刀具前角及工件轴向尺寸对工件双曲线误差的影响并提出以两段拆线或两段曲线刀刃替代一段直线或曲线刀刃的改进措施。     

圆体成形车刀加工圆锥面时双曲线误差的定量分析

分析了用圆体成形车刀加工圆锥面时产生双曲线误差的原因，并用数学推导方法求出了双曲线误差值的大小和各影响因素之间的关系。     

车刀安装位置造成的工件形状误差

车削加工过程中,影响工件形状误差的因素很多,对由机床精度、工件的装夹方法、加工工艺、车刀磨损等原因造成的形状误差,一般比较重视。其中车刀安装位置对车刀的前角、后角、主偏危、副偏角和刃倾角有很大影响,车刀安装位置的变动能显著改变切削力,而影响加工精度也是比较清楚的。但对车刀安装位置能够在一定条件下,影响工件的形状误差,这点一般认识不够清楚,进而造成工件在制造,检验     

棱体成形车刀廓形的简化设计与制造

通过建立成形车刀廓形设计的数学模型,探讨了棱体成形车刀廓形简化设计与制造的新方法,比起传统的方法有很大改进,对工厂技术人员有重要参考价值。     

加工复杂型面的棱体成形刀

在自动机床和自动线生产中,广泛采用棱体刀来加工各种复杂型面的工件,尤其是具有曲线部分型面的工件。但棱体刀由于有前、后角的关系,刀具廓形将不同于工件廓形而产生畸变。因此在设计和制造这种刀具时,必须对刀具的廓形进行修正计算。显然,加工工件的型面愈复杂,修正计算也愈繁琐。为了避     

棱体成形车刀廓形的简化设计与制造

通过建立成形车刀廓形设计的数学模型,探讨了棱体成形车刀廓形简化设计与制造的新方法,比起传统的方法有很大改进,对工厂技术人员有重要参考价值。     

关于逆向车削加工细长轴误差的力学分析

针对细长轴车削加工，分别在两种不同装夹条件下(一端卡盘夹紧、一端顶尖支承和两端顶尖支承)进行正向切削和逆向切削时的工件变形进行了力学分析，建立了正逆向切削工件在切削力作用下产生弯曲变形的解析模型。具体算例表明：逆向切削时工件的弯曲变形以及由此引起的加工误差远小于同等条件下正向切削的变形和误差。该模型及分析结果可用于细长轴加工的工艺设计。     

数控铣床实现小型零件车削的研究

本文从数控铣床的加工现状，研究扩展其加工功能，在加工方法，数控编程，刀具的选择，夹具的设计及定位，加工精度等相关技术要求上，探索实现小型零件车削的可行方案及使用功能，在加工设备的灵活使用上建立一种综合应用的思维方式。     

Automatic recognition of design and machining features from prismatic parts

Prismatic parts usually comprise basic features, such as slots, steps, holes, bosses, which may intersect with one another. In general, automatic recognition of intersecting features is difficult and may present bottlenecks when automating the design procedures which make use of features for downstream operations.This paper presents a novel approach to recognising intersecting features and auxiliary features due to tool movements and cutter radii. Since no cutting edges can be perfectly sharp, corner fillets on machined features are invariably created by end mills and other cutters. Fillets, on the other hand, could very well be features which have been designed to increase strength and reduce stress concentration of certain features. A feature recognition system is proposed to recognise features having fillets which may be either design or manufacturing features. This information will be useful to the product designer as it would be possible to distinguish between the intended and unintended features of a part. The developed system has been implemented on an HP-ME30 Solid Modeler.     

轧辊孔型强力切削抑制颤振的最佳走刀路线

阐述了数控强力切削轧辊孔型时发生颤振的问题,推导出切削深度与颤振的关系,并比较了几种走刀路线,提出了避免颤振的最佳走刀路线。     

基于车削加工工件测量的误差补偿技术

提出两种基于车削工件测量的误差补偿方法 ,即误差反向叠加的微进给补偿法与逆变刀具路线的软件补偿法 ,介绍这两种方法的原理与实现方法     

GA-based synthesis approach for machining scheme selection and operation sequencing optimization for prismatic parts

To obtain global and near-global optimal process plans based on the combinations of different machining schemes selected from each feature, a genetic algorithm-based synthesis approach for machining scheme selection and operation sequencing optimization is proposed. The memberships derived from the fuzzy logic neural network (FL-NN), which contains the membership function of each machining operation to batch size, are presented to determine the priorities of alternative machining operations for each feature. After all alternative machining schemes for each feature are generated, their memberships are obtained by calculation. The proposed approach contains the outer iteration and nested genetic algorithm (GA). In an outer iteration, one machining scheme for each feature is selected by using the roulette wheel approach or highest membership approach in terms of its membership first, and then the corresponding operation precedence constraints are generated automatically. These constraints, which can be modified freely in different outer iterations, are then used in a constraints adjustment algorithm to ensure the feasibility of process plan candidates generated in GA. After that, GA obtains an optimal process plan candidate. At last, the global and near-global optimal process plans are obtained by comparing the optimal process plan candidates in the whole outer iteration. The proposed approach is experimentally validated through a case study.     

Evaluation of form error at semi-spherical tools by use of image processing

In this study, a method is proposed for dimensional measurements of semi-spherical parts for the standard tool electrodes used in Electrical Discharge Machining (EDM). The tool electrode to be measured is magnified by a profile projector. Pictures of some equatorial plane projections of the electrodes are captured by a digital camera before and after machining. The pictures were calibrated with the geometric camera calibration. Then, the profiles are extracted from their background using the adaptive threshold, which is an image processing method. 2D coordinates are first obtained and then converted to 3D coordinates. Using the obtained data, sphericity and radius are calculated by means of the minimum zone method. It is seen that the proposed method can be used for determining the EDM tool electrodes’ form error.     

非圆等宽截型零件的车铣加工运动设计

从非圆等宽截型零件的型线描述着手，给出了等宽截型零件的截面廓形设计方法，提出了任意非圆等宽截型零件的车铣组合加工新模型，并通过模拟仿真证明了有关理论与方法的可行性。同时，根据模型构造了非圆等宽截型零件加工机床的基本结构形式，并进行了机床运动设计及运动轴配置。为非圆零件通用化加工机床的产业化提供了较好的理论基础。     

环形件数控强力车削抑制颤振的最佳走刀路线

阐述了环形件数控强力车削加工中的颤振问题,提出了数控强力车削环形件避免发生颤振的最佳工艺路线和极限切深。     

面向数控机床随机误差的加工优化方法研究

针对随机误差难以进行误差补偿,同时,随机误差在机床加工区域内分布不均的问题。提出一种根据机床随机误差分布规律,结合待加工零件尺寸精度要求,优化零件加工区域的方法,提升零件加工精度。首先采用多体系统运动学原理,建立机床随机误差对加工位置和姿态的关系;而后结合待加工零件精度要求,建立零件加工位姿的优化模型,并通过KS函数,将局部最优化问题,转化成全局可导优化模型;并针对零件位姿与优化目标和约束函数难以获得显式表达关系的问题,通过RBF响应面,建立优化元模型;最后通过优化算法进行寻优,优化零件加工位姿,提高零件加工精度。为验证所提方法的正确性和有效性,进行了仿真实验分析对比。