用切割装配体实现复杂钣金件展开设计

提出了一种用装配体切割实现锥管类相贯体零件的设计方法,此方法主要利用实体造型软件生成钣金零件间的相贯曲线,然后对经过虚拟切割已带有相贯特征的钣金零件虚拟展开,就完成了钣金零件的展开设计,从而解决了传统相贯体钣金展开设计中的难点.文章通过实例对设计方法进行了验证.     

基于CATIA的钣金零件展开

从原理上进行了钣金零件几种展开方法的对比,通过典型实例验证了基于CATIA的钣金零件展开法的优越性及实用性,为钣金零件设计及加工的方式提供一种新的思路。     

基于SolidWorks的钣金参数化设计制图二次开发

基于SolidWorks的多实体钣金零件设计和API二次开发功能,实现钣金自动化展开和工程图输出。采用模型尺寸变量与VB编程技术相结合的思路,创建钣金零件参数化建模与制图程序。从而突破传统的、重复性的逐一钣金零件展开制图方法,提升设计员的工作效率,节约成本。     

CADMAN编程软件在钣金加工中的应用

CADMAN是比利时LVD公司开发的CAD/CAM软件，主要用于钣金零件的三维设计、展开计算和数控折弯加工编程。这里简要介绍了该软件在三维钣金设计上的一些主要特点，以及用该软件进行展开计算和数控折弯加工编程的基本过程。     

钣金零件展开图的生成

讨论计算机辅助钣金工艺设计（CAPPforsheetmetal）中零件展开图的生成。提出了一种基于特征技术的能够生成正确的、包含丰富工艺信息的板金零件展开图的生成算法。     

基于IGES的钣金零件特征识别的方法研究

针对钣金设计软件数据模型的外部读取与特征识别问题,对钣金设计软件的数据共享、IGES文件结构以及零件特征分类进行了研究,提出了一种基于IGES曲面模型的后置处理方法,通过遍历IGES文件,获取了钣金零件的所有裁剪参数曲面信息,建立了以折弯面作为结点的双向链表的数据结构,根据IGES文件的数据特征,对钣金零件进行了特征分类,提取了钣金折弯特征并建立了特征间的依赖关系。利用Pro/E软件绘制的钣金零件对特征识别方法进行了测试。研究结果表明,该方法能够准确地获取钣金的特征,为钣金零件折弯仿真与工序规划提供了可靠的特征数据,使得产品开发周期缩短了近30%,最终实现了钣金加工的精确性与高效性。     

关于2D钣金零件的几何造型方法的简述

针对2D钣金零件，对2D钣金零件的几何造型方法作了简单介绍，希望对提高钣金模具的设计质量有所帮助。     

基于SolidWorks的钣金件展开的应用

本文介绍一种基于三维实体模型下的钣金零件的建立及展开方法,快速准确取得钣金零件的展开图数据及相关质量特性,方便实现CAD／CAM及数控切割加工。     

基于XML的钣金工艺实例表达

针对已有的基于实例推理的钣金工艺设计系统中,工艺实例表达模型单一,工艺信息共享困难等问题,提出了基于XML的多层次钣金工艺实例表达方式.在对钣金零件进行层次划分后,采用XML描述钣金零件的工艺信息及制造指令,完整表达了钣金工艺实例,同时提供了一种解决工艺信息共享困难的方法.     

材料有效利用率在钣金成本优化中的应用

通过对钣金零件进行工艺分析,提出应用材料有效利用率来平衡钣金成本设计中零件最简原则和零件最少原则这一对矛盾,并给出具体案例,为钣金成本优化提供了一种新的方法。     

An Information Modelling Framework to Support Intelligent Concurrent Design and Manufacturing of Sheet Metal Parts

Sharing of information is an important issue in supporting integrated and rapid product development. The use of information modelling technology is a promising approach for solving the problems of the intensive sharing of information in a concurrent and rapid product development cycle. This paper explores the definition and the structure of a framework of information modelling for the concurrent design and manufacturing of sheet metal parts. This framework aims to build an information bridge to fill the gap between the sheet metal part design and manufacturing systems. It is based on abstract handling principles of entities called zero thickness and zero bend radius principles. Based on this framework, information models can be built for information sharing by different systems. Knowledge bases that support intelligent concurrent design and manufacturing can also be created. In this paper, a two-branch tree based stepping-structure information modelling methodology for sheet metal parts is described, and a case study is given.     

Simulation and Experiment on Workability for Cold Pressure Forming of Sheet Metal Part with Step Cross-section

In modem manufacturing, a new type of sheet metal part with step cross-section in both inner hole and outer edge is proposed. The traditional stamping separating processes can only produce sheet metal part with vertical cross-section. According to the latest developing theory and potential of cold pressure forming: combination of pressure and cold forging, a new flow control forming of sheet metal(FCF) is excogitated based on blanking process of general stamping and combined with cold forging processes such as extrusion and coining, etc, which is aiming at the above-mentioned new type of sheet metal part. With utilization of this new process, the new type of sheet metal parts can be manufactured. In order to shorten the testing period, the numerical simulation was carried out by using DEFORM-3D software, and both deformation and mechanics rules were analyzed. Based on the simulation, both punching part and blanked parts of this new type were successfully developed. Then a new conception of optimal distance between the step walls of inner hole and outside edge was proposed and the design principle for its numerical value was inferred. Furthermore, a mold set for combination of stamping & cold forging was designed and manufactured, by which the technologic experiments were taken for validation with Aluminum plate of thickness 2.35 mm for power battery cover board, which verified the principle of the distance between the step walls. The research of cold pressure forming of thin sheet metal with step cross-section is significant, not only to the development of modem mechanical manufacture, but also to metal plastic forming science.     

A parametric study of sheet metal joints for dimensional integrity

The characteristics of joints between parts are one of the most critical issues in variation simulation analysis. This paper presents a parametric study of the dimensional variation characteristics of butt joints and slip joints. These two basic joints encompass the whole domain of joints used in sheet metal assemblies for structural extension. A geometrical model was proposed for predicting the assembly variation in order to take into consideration the possibility of part deformation and tool variation. Butt joints act like rigid bodies in the normal direction. For slip joints, the sensitivity coefficient in the slip direction is a function of tooling variations. The variation from individual part and tooling can be eliminated or substantially reduced if the product structure and assembly process is properly designed. A simple four-part assembly example shows the structure and assembly process. This result provides improved understanding of sheet metal assembly processes and provides a new idea for adaptive product and process design.     

A parametric study of sheet metal joints for dimensional integrity

The characteristics of joints between parts are one of the most critical issues in variation simulation analysis. This paper presents a parametric study of the dimensional variation characteristics of butt joints and slip joints. These two basic joints encompass the whole domain of joints used in sheet metal assemblies for structural extension. A geometrical model was proposed for predicting the assembly variation in order to take into consideration the possibility of part deformation and tool variation. Butt joints act like rigid bodies in the normal direction. For slip joints, the sensitivity coefficient in the slip direction is a function of tooling variations. The variation from individual part and tooling can be eliminated or substantially reduced if the product structure and assembly process is properly designed. A simple four-part assembly example shows the structure and assembly process. This result provides improved understanding of sheet metal assembly processes and provides a new idea for adaptive product and process design.     

Development of a layered manufacturing system using sheet metal-polymer lamination for mechanical parts

Layered manufacturing enables us to make 3D objects rapidly and directly from 3D-CAD data and enables us to handle any design changes. But materials such as light cured polymers, paper, or wax don’t have enough strength to be used directly as mechanical parts. In order to solve such problems, layered manufacturing using both sheet metal and polymers is proposed in this paper. By using sheet metal and polymers, high strength parts with high dumping functions, suitable for use as mechanical parts can be manufactured. Also, a special unit for layered manufacturing is developed, which is designed to be coupled with a desktop NC milling machine, and can make 3D objects easily.     

Challenges of manufacturability and product data management in bending

Effective production in a networking environment of sheet metal products needs accurate and relevant PDM (product data management) data, appropriate modeling of components supported by local and global network solutions, and utilization of advantages of feature-based modeling. To enable these aspects of effective production in sheet metal production, it is necessary to evaluate the integration of DFMA (design for manufacturing and assembly) and PDM. This paper aims at identifying the challenges of DFMA and PDM integration through recognizing possible malfunctioning parts of their integration. The observations are based on sheet metal specimens in which the DFMA and PDM aspects are visible in punching and bending. This study will focus on five issues that are included either in DFMA or PDM, or both: the effects of different calculation methods for the flattened length, utilization viewpoints of global or local manufacturability guidelines, assembly conditions, options to tune the manufacturing process instead of changing the product geometry, and possible additional requirements given by the customers. Based on practical design and manufacturing tests, it has become evident that one option to improve the quality of analyzed sheet metal parts is to further develop the integration of DFMA features with the workshop’s cutting and punching parameters. As one possible improvement to these kinds of integration tasks of DFMA and PDM, it is suggested that the responsibilities for developing DMFA and PDM applications with proper design parameters could be analyzed more deeply between persons working with information exchange, product design, software design, or production machine design.     

A new sheet metal forming system based on incremental punching, part 2: machine building and experiment results

The paper is the second of the two papers on a new sheet metal forming system of incremental punching. In the first paper, the mechanics model is introduced, and the computer simulations are carried out. This paper consists of two parts: the design and building of an incremental punching machine and experiment results. The machine is a three-axis computer numerical controlled (CNC) machine with a high-speed hydraulic punching head. Given a part, the punch path can be generated using commercial CAM systems with some modifications. Then, the machine takes over forming the part punch by punch. The formability of this system is also investigated giving the maximum forming angle. Following the first paper, two examples are studied in details. The experiment results indicate that the new system is effective for sheet metal rapid prototyping. Finally, some future research topics are discussed.     

钣金冲模集成制造系统的产品信息建模

计算机集成制造是模具生产集成化和智能化的最高体现,建立钣金冲模产品信息模型是实现模具集成制造的基础。本文针对钣金冲模集成制造的功能模块,建立系统的功能模型,并给出结构化分析的 Ｉ Ｄ Ｂ Ｆ０ 图形表达;分解模具集成产品模型为制件模型、制件展开分析模型、工步设计模型、模具设计模型、零件设计模型、数控加工模型和模具装配仿真模型等,并用 Ｅ Ｘ Ｐ Ｒ Ｅ Ｓ Ｓ语言建立信息模型。     

优化板料成形状态的新技术

为了解决一些形状复杂的薄板零件在实际生产中存在的问题，提出了优化板料成形状态的思想，介绍了一种既能有效地减小薄板成形时法兰面上流动阻力极大区域内的流动阻力，又不会增加起皱趋势，进而优化板料成形状态的新工艺措施。对这一措施进行了较为精确的有限元数值模拟和机理分析。