模具CAD/CAM技术的应用与发展

为了促进我国模具工业更好地应用CAD/CAM技术来提高企业经济效益和竞争能力,中国模协技术委员会在浙江省余姚市召开了模具CAD/CAM技术研讨会。 与会代表针对我国模具行业开展CAD/CAM技术研究与应用的过程,产生的效益和应用开发的经验与体会,广泛交流了各自的看法,形成了一些比较一致的意见;对高校研究机构如何开展模具CAD/CAM一体化工作,也发表了许多好的意见。下面就模具CAD/CAM应用、值得注意解决的问题和模具CAD/CAM技术的发展分別加以阐述。 模具CAD/CAM技术的应用     

铝型材挤压模具CAD/CAM集成制造

本文结合金鹏铝业铝型材模具CAD/CAM集成制造的实施案例,介绍了模具CAD/CAM的软硬件集成环境及信息集成过程,指出了集成技术的关键在于CAD与CAM之间的数据和信息的自动化传递与转换.     

模具CAD／CAM软件的应用与开发现状

本文首先分析了模具行业采用模具CAD/CAM技术的原因。接着阐述了模具CAD／CAM应用情况和开发现状,最后指出了我国模具CAD／CAM软件应用与开发中存在的主要不足。     

探讨模具CAD/CAM软件开发

模具CAD/CAM是在CAD和CAM独立发展的基础之上,在模具生产当中使用计算机技术,让模具的生产有了一个飞跃。阐述了此种技术的发展情况、软件的特性、软件所具有的优势,探讨了在模具的生产中使用CAD/CAM的原因。通过分析当前CAD/CAM的开发情况及具体的应用,指出了在实际开发中所存在的问题。     

基于Cimatron E的模具数控加工

CAD/CAM软件经过40多年的发展,国内外都有了很多较为成熟的产品.Cimatron E是以色列Cimatron公司主要针对模具行业开发的CAD/CAM系统软件,是目前模具行业应用广泛的CAO/CAM软件,该软件对模具的设计、加工制造有较好的解决方案.特别是在加工方面,提供了灵活的2D和3D铣削策略.下面以一个型腔模为例,介绍Cimatron软件在模具铣削编程中的应用.     

论加强模具专业学生CAD／CAE／CAM技术应用能力

本文从CAD/CAE/CAM技术应用能力,以及模具设计与制造专业人才水平的关系入手,阐述了CAD/CAE/CAM技术在模具设计与制造中的作用,分析了当前高校CAD/CAE/CAM技术课程开设情况及教学效果,提出了提高高校模具相关专业学生CAD/CAE/CAM技术应用能力的应对措施.     

注塑模CAD/CAE/CAM集成系统的开发

本文论述了注塑模CAD/CAE/CAM集成系统HSC1.1。CAD部分包括图形输入、型腔及型芯曲面生成、标准模架选择以及模具结构设计模块; CAE部分包括流道平衡、流动模拟、冷却分析以及模具零件强度与刚度校核模块;CAM部分包括数控线切割与数控铣削加工刀具轨迹生成模块。目前,该系统经改进已成功地在许多工厂中得到应用。     

汽车车身零件设计与模具设计的工艺分析技术

随着加入WTO,我国的工业面临着巨大的挑战,技术领域的竞争已经成为企业生存和发展的一个重要砝码.特别是汽车工业,以有限元法为代表的数值模拟系统已经与CAD/CAM系统相结合,形成模具设计、分析与加工一体化的CAD/CAE/CAM集成系统,其目的在于减少模具的设计与调试周期、降低模具加工成本,并提高产品质量与市场竞争力.     

基于Pro/ENGINEER与MasterCAM的模具设计与加工

随着计算机技术的迅猛发展,工业设计领域的CAD/CAM软件也得到了前所未有的发展,各种三维CAD/CAM软件应运而生,且各具特色.Pro/ENGINEER是美国参数技术公司(PTC)推出的一套三维CAD/CAM参数化软件系统,它功能强大、内容丰富,提供了零件设计、产品装配、模具开发、NC加工、钣金件设计、铸造件设计、自动量测、机构仿真和应力分析等多种功能,已被广泛地应用于机械、汽车、航天、家电、玩具、模具、工业设计等行业.     

铝型材挤压模具的CAD/CAM集成制造

本文结合金鹏铝业铝型材模具CAD/CAM集成制造的实施案例介绍了模具CAD/CAM的软硬件集成环境及信息集成过程指出了集成技术的关键在于CAD与CAM之间的数据和信息的自动化传递与转换一 引言铝型材制品的生产过程从市场需求分析开始经过工程设计和制造加工使之从抽象的概念变成实物产品具体的作业流程如图1所示图1 产品生产过程在铝型材生产制造过程中许多工厂已开始应用或部分应用计算机辅助单元技术CADCAPPCAM来承担产品及模具的设计工艺过程设计和模具制造等工作由于这些各自独立的单元技术系统不能实现系统之间的信息自动传递…     

Automation in the design of EDM electrodes

Plastic parts, especially those designed for consumer electronics products, are becoming more compact and freeform in shape. This requires the construction of compact and delicate geometric features in the injection moulds that produce these parts. It is now common practice to employ electric discharge machining (EDM) whenever the conventional machining process fails to machine such delicate features. Although CAD/CAM systems are widely used in mould design and manufacturing, and specific commercial CAD/CAM systems that are customized for injection mould applications are also available, there are still no intelligent CAD tools that address the specific requirements of EDM electrode design. The aim of this research is to develop an intelligent CAD tool that supports EDM electrode design. This CAD tool uses a new technique that recursively splits the EDM region into sub-regions until machinable electrodes can be constructed. The CAD tool has been implemented and integrated into a commercial CAD/CAM system, and 40 different real designs has been used to test its capability in handling a wide variety of geometric shapes. Performance data show that the efficiency of the design process can be improved by at least 50%, with a potential to achieve 85% through improved implementation and further research.     

CAD/CAM 外部数据库系统的研究与应用

CAD/CAM 软件的二次开发越来越受人们的重视,而建立自己的数据库与 CAD/CAM 软件集成是重中之重。本 文在著名的 CAD/CAM 软件 PRO/E 的基础上,结合 VC.NET,用 ADO 技术对外部数据库的连接方法进行了研究,并根 据实际需求建立了一套属于自己的刀具数据库系统。     

A proposal for CAD/CAM interface with expert systems

In the computer-integrated manufacturing (CIM) environment, the key technologies, CAD and CAM, should be fully integrated with high operability. It is claimed, however, that CAD and CAM have so far been developed independently. Although much effort has been made to integrate CAD and CAM, this reality is far from completion.

Therefore, to establish a CAD/CAM interface with higher integration, the concept of a computer-aided drafting procedure with expert systems has been proposed on the basis of analysis of the information explicitly and implicity described on the part drawing, and also of the required knowledge of the designer to produce the part drawing. The CAD/CAM interface proposed here is available for producing not only the part drawing but also the process plan for the corresponding part, by effectively utilizing the knowledge of the expert. A prototype CAD/CAM interface deals with axi-symmetrical rotational parts implemented on a workstation.     

Development of a collaborative CAD/CAM system

This paper presents the development of a collaborative CAD/CAM system (COCADCAM). COCADCAM extends an existing single-location CAD/CAM system to a multi-location CAD/CAM application so that two geographically dispersed CAD/CAM users can work together on a three-dimensional CAD-geometry coediting and CAD-related tasks collaboratively and dynamically. COCADCAM dynamically supports CAD data communication that are not available in traditional single-location CAD/CAM. The dynamic data communication is achieved through the development of networking algorithms and CAD/CAM functions in this paper. The networking algorithms based on UNIX Interprocess Communication (IPC), the Network File System (NFS), and a connection-oriented client and server model under the Transmission Control Protocol/Internet Protocol (TCP/IP) suite. The CAD/CAM functions included surface modelling, simulation of a milling toolpath, and post-processing of an NC program following collaborative CAD-geometry coediting, which are directly or indirectly supported by the Application Programming Interface (API) of the CAD/CAM software. The networking algorithms and CAD/CAM functions together can facilitate an environment for CAD-geometry coediting and related tasks such as design, analysis and manufacture. COCADCAM has been successfully implemented through local area network (LAN) and the Internet; a remote machining cell is also linked so that the generated NC program based on a coedited free-form surface can be used for the physical machining operation. The algorithm proposed by COCADCAM can be referenced for the extension of other single-location CAD/CAM systems to multi-location applications.     

Theories for graphics processors in TIPS-1

This paper describes the theoretical aspects of graphics processors in CAD/CAM system TIPS-1. As one of the man-machine interfaces in the CAD/CAM field, computer graphics plays an important role. And this field, computer graphics involves not only image processing with shaded pictures produced by raster scan displays but also sectional and/or perspective view drawing picture by line drawing display. By using TIPS-1 graphics processors, we can get both raster scan and line drawing pictures for the same of modeled 3-D geometry. The following items are considered as the necessary conditions for developing graphics processors.

• • To develop geometric modeling theory.

• • To develop generative geometry pattern processing theory.

• • To implement problem-oriented graphics routines based on above conditions.

How to complete these conditions is described with several figures and graphic outputs.     

协同开发环境中的CAD/CAM集成数据管理的实现

协同开发环境是虚拟企业高效运作的支撑平台,CAD/CAM集成系统是该环境中的重要子系统,迫切需要对CAD/CAM集成数据进行有效的管理和操作。文章讨论了协同开发环境中CAD/CAM集成数据的管理技术,并详细分析了CAD/CAM集成数据库的数据结构和数据集成。     

Adding draft angles on mechanical components containing constant radius blending surfaces

The automation of mould design and manufacturing using computer-aided design and computer-aided manufacturing (CAD/CAM) draws the attention of many researchers. However, little attention is given to the automation of draft angles addition process. Draft angle is an important feature that facilitates the ejection of moulded parts. Existing algorithms for draft angles addition are still having limitations, especially for geometry with blending surfaces. A new approach for draft angles addition is introduced. It reduces the workload of users by automatically producing inclination on surfaces that require draft angles.     

CAD/CAM integrated system in collaborative development environment

For virtual enterprises to realize efficient operation in the 21st century, it is necessary to develop an environment that can support collaborative work of multi-disciplinary groups distributed in different places. CAD/CAM integrated system is an important subsystem in this environment. In this paper, the structure of CAD/CAM integrated system is presented, then, key technologies related to realize CAD/CAM integration are discussed in detail and finally main functions and an application case of CAD/CAM integrated system is introduced.     

CAD mesh model segmentation by clustering

CAD mesh models have been widely employed in current CAD/CAM systems, where it is quite useful to recognize the features of the CAD mesh models. The first step of feature recognition is to segment the CAD mesh model into meaningful parts. Although there are lots of mesh segmentation methods in literature, the majority of them are not suitable to CAD mesh models. In this paper, we design a mesh segmentation method based on clustering, dedicated to the CAD mesh model. Specifically, by the agglomerative clustering method, the given CAD mesh model is first clustered into the sparse and dense triangle regions. Furthermore, the sparse triangle region is separated into planar regions, cylindrical regions, and conical regions by the Gauss map of the triangular faces and Hough transformation; the dense triangle region is also segmented by the mean shift operation performed on the mean curvature field defined on the mesh faces. Lots of empirical results demonstrate the effectiveness and efficiency of the CAD mesh segmentation method in this paper.     

基于层次结构的特征及其在CAD／CAM中的应用

特征的研究近年来得到长足的发展。然而由于特征的发展与人的思维和工程应用的背景相贯通，造成特征定义的不统一，因而限制了特征在ＣＡＤ／ＣＡＭ中应用，。使基于特征的ＣＡＤ／ＣＡＭ集成难以实现。文中把特征放在ＣＡＤ／ＣＡＭ集成的全局来考虑，不单单只是从特征的形状出发，而是同时从设计与加工两个角度出发来描述与定义特征。