加工中心上Master CAM刀具半径补偿功能的应用

文中就Master CAM的刀具半径补偿功能在加工中心上进行外形铣削、挖槽加工的应用方法进行了分析.     

基于MasterCAM的刀具路径区域控制研究

Master CAM软件是一款非常优秀而专业的数控加工自动编程软件,拥有如挖槽加工、等高外形、环绕等距等十几种曲面粗精加工方法,每种曲面加工方法都有各自的特点和适应范围,对复杂曲面进行加工时,特定的加工区域总是对应一种最优曲面加工方法。所以在利用Master CAM软件进行数控加工编程时,通过采用限定刀具的背吃刀量、限制刀具边界、设置干涉面、添加辅助线、修剪刀具路径等措施来限定刀具切削的范围,控制加工区域,从而提高产品的加工效率,保证加工质量。     

外形铣削在数控铣自动编程中的应用

主要阐述如何将Master CAM中外形铣削功能应用于铣削外形、平面、孔、槽等加工,实现更简便的程序编制。并且通过刀具路径的对比及分析,以便更清楚地理解外形铣削的加工优势。     

基于MasterCAM X的孔类数控快速自动编程方法

孔加工中,刀具尺寸因受孔尺寸的限制往往刚性差,切削用量不宜过大,一个孔的加工往往需要用到几种不同的刀具,因此,利用CAM软件编程时刀具定义及加工参数的设置过程较为繁琐,并且对编程者经验依赖性较强,利用Master CAM X Mill模块中全圆铣削路径下的自动钻孔和全圆铣削命令,可减少刀具定义及参数设置的时间,从而对于提高孔的编程效率具有实际意义。     

数控型腔铣削加工稳定性预测

数控型腔铣削加工过程中,铣刀进入拐角时,刀具-工件间啮合信息的变化通常会引起颤振。针对这一状况,在用半离散算法对刀具-工件啮合状况恒定铣削加工稳定性预测的基础上,结合数控型腔铣削加工过程中加工路径引起的刀具-工件间啮合信息的变化,针对给定的加工路径提出了型腔铣削加工稳定性预测的方法。试验证明,该方法能在数控加工时对型腔加工过程中的铣削稳定性进行成功预测。     

多轴铣削加工表面形貌建模与仿真研究分析

在考虑刀具偏心的情况下,建立多轴铣削加工形貌仿真模型,推导出多轴铣削情况下球头铣刀切削刃上任意一点相对被加工工件的轨迹方程,建立仿真算法求解被加工工件表面残留高度,并对平面铣削加工以及圆弧面铣削加工分别进行铣削仿真研究,研究刀具轴线角、进给倾角分别对表面粗糙度的影响。通过提高铣削过程中被加工工件表面质量,为开发实用的铣削加工过程物理仿真系统奠定了坚实的基础,对发展数控加工技术和指导实际生产具有一定的意义。     

高速铣削球头立铣刀加工倾角的研究

球头立铣刀铣削曲面时,刀具轴线与工件曲面法线之间的夹角对工件表面质量及刀具寿命有着重要影响,在扼要介绍高速铣削对球头铣刀要求的基础上,通过对球头铣刀刀具轴线和工件加工表面之间的倾角研究,得出了调整刀具和工件之间的加工倾角,有效改善切削条件的策略,对高速铣削参数以及刀具切削路径的优选具有一定的指导意义.     

优质高效加工空间曲面的方法——线框刀路

探讨了Master CAM软件中能生成数种特殊曲面加工刀具路径的方法——线架加工法,并对其功能和应用作了初步探索,希望能为学习其他CAD/CAM软件曲面加工方式提供借鉴。     

MasterCAM刀具半径补偿功能的应用

通过Master CAM的刀具半径补偿功能可以方便的控制外形铣削的尺寸精度。介绍了MasterCAM的“电脑（软件）”、“控制器”、“两者”等3种常见补偿方式，分析了每种补偿方式在数控编程中的应用特点。     

再生振动和刀具偏心对立铣加工精度综合影响的研究

基于再生振动和刀具偏心对立铣加工过程的影响,建立了改进的动态切削力和切削厚度的非线性数学模型;利用计算机仿真技术,定量分析了上述因素对铣削加工振动和工件三维表面形貌的综合影响。结果表明:考虑再生振动和刀具偏心的综合影响,可使铣削振动的预测精度较未考虑这两个因素时平均提高20%以上,使加工振动状态更接近实际加工情况。     

A new approach to generating arc length parameterized NURBS tool paths for efficient three-axis machining of smooth, accurate sculptured surfaces

With the development of a new function of computer numerical control controllers, nonuniform rational B-spline (NURBS) interpolation, NURBS tool path generation for sculptured surface machining is under extensive research. The common procedures of the current NURBS tool path planning methods are as follows: first, to find a group of cutter contact points on a sculptured surface; second, to calculate their corresponding cutter locations (CLs); then, to fit a NURBS tool path to the CLs within a prescribed tolerance; and finally, to inspect the tool path for possible gouge by the tool and delete the invalid path segments, if any. However, the NURBS tool path has the following problems: (a) although it passes through the discrete CLs of the theoretical CL path, the deviation along the two paths could be larger than the tolerance; (b) its parameter is not the arc length of the path; and (c) it is difficult to detect gouge along the NURBS path and to remove the invalid segments from it. Consequently, NURBS tool paths generated with the current methods of commercial computer-aided design/computer-aided manufacturing (CAD/CAM) software cannot be used to make smooth and accurate surfaces. To address these problems, this work proposes a new approach to generating arc length parameterized NURBS tool paths with high accuracy in terms of the theoretical CL paths and without gouge and interference. Two practical examples in this work clearly demonstrate the feasibility of this approach and the advantages of the generated NURBS tool paths. Therefore, this approach can be implemented into the CAD/CAM software to promote NURBS machining in industry.     

Analysis of drift in iso-scallop planning—machining by regions

Computer-aided manufacturing (CAM) occupies an increasingly significant role in engineering with all it has to offer in terms of new possibilities and improving designer/manufacturer productivity. Our present work is devoted to the integration of a module for automatic generation of cutter paths into a CAM program to machine freeform surfaces by end milling. The study addresses the more global issue relating to the adoption of tool path planning with constant scallop height. For present purposes, the cutter geometry is taken as given and does not enter into the study’s parameter choices. The main problem posed by planning for iso-scallop tool paths lies in the management of drift in trajectories, which leads to the path looping due to the fact that global programming over the surface remains unattainable. The proposed solution is to define surface subdivision criteria (machining by regions) enabling iso-scallop planning to be implemented in each region. We conducted our study on a three-axis numerical control machine tool.     

Gouge-free voxel-based machining for parallel processors

Manufacturers produce complex parts by utilizing computer-aided manufacturing (CAM) software to generate tool paths for a machine tool to follow. CAM systems traditionally rely on parametric surface representations of the parts and complex algorithms to produce the tool paths. This paper presents a new path generation framework that is based on parallel algorithms and hardware that utilizes voxel models. The use of new parallel algorithms allows rapid calculations of tool paths automatically from the voxel model. The core components of this framework are a method of generating digital voxel models from tessellated surface models, a method to obtain digital surface information by a parallel ray-casting approach, and a new approach to calculate gouge-free tool paths in parallel from surface information and generalized cutting geometry. The performance of utilizing digital models within this framework is then discussed with respect to timing and actual cutting results.     

并联机床加工船用螺旋桨及CAM技术研究

主要研究用并联机床加工整体式船用螺旋桨的技术以及用CAD／CAM系统进行螺旋桨辅助加工的方法。研究了并联机床加工螺旋桨的工艺方案，提出了加工螺旋桨的并串联多轴数控加工系统，分析了螺旋桨数控加工的工艺过程；介绍了在UG／CAM环境下进行螺旋桨加工的刀具轨迹编程和用Vericut加工仿真系统进行加工仿真的方法和过程；并进行加工实验。用于加工螺旋桨的并联机床具有结构简单，造价低和占地面积小等优点，具有广泛的应用价值和发展前景。     

综合应用Pro/Engineer与Master CAM对零件进行编程

针对在工程中只应用某一编程软件完成零件的编程过程较复杂、效率不高的问题,根据Pro/Engineer与Master CAM编程软件的特点,以凸模为例,介绍了如何将Pro/Engineer图形格式转化成Master CAM 图形格式,并在Master CAM中编制加工刀具路径,生成NC代码以及对其修改,传输给数控机床加工的方法,这样,可以有效地发挥编程软件的功能, 提高机械制造的质量和效率.     

复杂曲面模具测量、造型与加工一体化系统——3MS

介绍了复杂曲面模具测量、造型与加工一体化系统（３ＭＳ）的结构和主模块功能，重点分析了ＣＡＭ模块的设计思想。该系统是基于复杂曲面模具测量、造型和制造一体化的概念而开发的，其核心包括散乱数据的三角划分及其网格优化、三角曲面造型和刀具加工轨迹生成等模块。     

交互式虚拟设计与同步制造技术算法与图形系统研究

产品的创意外形设计与快速试制对于更好地满足产品多品种、短开发周期、优美外形、提高市场竞争力等需求具有重要意义,而现有的CAD/CAM和快速原型制造技术在这一方面仍然存在一些不足,这里提出的交互式虚拟设计与同步试制系统利用虚拟现实技术和计算机数字雕刻技术,在交互设计、创意设计、快速试制、材料多样性等方面都有所突破。文章阐述了在设计过程中工作描述、刀具轨迹包络计算、图形布尔运算、以及高速逼真图形显示等关键技术。实际工作设计与制造实验证明所开发的系统技术可行,已经可以进行基本的产品外形设计与同步制造。     

Iso-parametric CNC tool path optimization based on adaptive grid generation

The iso-parametric tool path is broadly used in CAM systems to machine sculptured surfaces. To satisfy tolerance constraints CAM systems usually adopt the smallest intervals across discrete tool paths, leading often to overlap and inefficient tool path. This paper presents a novel optimization scheme based on adaptive grid that can produce the optimal tool path on the basis of iso-parametric tool path and introduces the numerical method of generating the adaptive grid. When the generated optimal tool path has the same number of discrete tool path as the iso-parametric tool path, the optimal tool path will produce smaller machining errors. Or when the generated optimal tool path produces the same errors as the iso-parametric tool path, the optimal tool path will have fewer discrete tool paths and higher efficiency. This optimization scheme is robust, concise, and easy to be integrated into CAM systems to produce the optimal tool path automatically.     

基于Cimatron E7.0的模具高速加工编程模板设计

论述了高速加工技术应用于模具制造的优点及当前存在的问题。总结了高速加工对刀具路径要求。以飞轮壳凹模高速数控加工程序编制为例,详细介绍了利用Cimatron E7.0软件编制模具高速加工程序的方法。提出了利用设计模具编程模板解决当前某些问题的方法。编程模板在模具数控加工中的应用,实现了CAPP与CAM编程的一体化操作和信息的有效集成,帮助工艺人员快速、精密地完成零件的加工制造,并且不仅使加工效率大大提高,还使模具表面质量更佳,使用寿命更长。