特殊薄壁零件压铸模新型桥接式浇注系统的研究

对于某些特殊结构的薄壁箱体形压铸件,当采用常规的浇注系统时,无论浇口的位置与尺寸参数如何选择都很难保证压铸工艺的稳定性,铸件的尺寸精度与表面质量低,废品率高。针对这一生产问题,在生产实验研究的基础上,设计了一种新型桥接式浇注系统,并结合实例给出了内浇口尺寸参数的确定原则,保证了此类压铸件的工艺可靠性,提高了压铸件的尺寸精度,避免了“冷隔”和过大的变形,确保了压铸件质量。     

A Hybrid Intelligent Systems Approach for Die Design in Sheet Metal Forming

Die design is heavily experience based and the die design process is an iterative procedure of trial and error in order to obtain a final die design for the successful manufacture of stampings. Most automotive industries use internal guidelines and past experience for die design. Even though powerful computer-aided design systems are being used in automotive industry, the lack of adequate analysis tools at the initial die geometry design stage hinders the die manufacturing process, and also necessitates lead times of the order of 5–30 weeks [1]. At the concept design stage, and during the initial die development process, the variations in geometry and process conditions are so large that it is prohibitively expensive to use 3D finite element analysis. The complexity of die design heuristic knowledge hinders the development and application of knowledge-based systems. Hybrid intelligent systems are computer programs in which at least one of the constituent models simulates intelligent behaviour [2]. These models could be knowledge-based systems, artificial neural networks, fuzzy logic systems, etc. In this approach both artificial neural networks, knowledge-based systems and finite-element analysis (FEA) for modelling the design process are used. A simulation-based design approach [3] for the die design process is followed. Artificial neural networks (ANNs) are preliminary design tools which indicate the formability of the component geometry, for the selected process and material conditions. The ANN module is trained from FEA results for a generic set of component geometries, process conditions, and material properties. The final die design validation is carried out by FEA. The intelligent frame-work incorporates rules for material selection, process parameter selection and their modification. Component geometry is a critical parameter which affects the manufacturability of the given part. Hence, an intelligent geometry handling module, which automatically modifies and optimises the geometry of the designed die, is implemented in the present system. Knowledge-based blackboard architecture is used for the integration of various analysis models such as CAD, FEA, and ANN, as an intelligent framework for die design [4]. The hybrid intelligent system provides an integrated decision support environment for simulation and analysis of the forming process, both during the initial die design phase and during the die tryout phase. The hybrid intelligent systems approach supports the capability for automatic evaluation of prospective die design for manufacturability, and performs automatic modification of design inputs. Applications of the hybrid intelligent system for die design are described together with a comparison with shop floor data.     

微波功率管壳用焊料浇铸模的设计与制造

介绍一种微波功率管壳用焊料的模具的设计、制造工艺、表面处理和测量方法。     

热作模具钢及压铸模具钢的发展和应用

介绍了我国新研制的热作模具材料的性能和应用概况，并和常用材料进行比较，对选用热作模具材料有实际指导意义。     

An Automated Process Planning and Die Design System for Quasi-Axisymmetric Cold Forging Products

This paper deals with an automated computer-aided process planning and die design system with which a designer can determine operation sequences even after only a little experience in process planning and die design of quasi-axisymmetric cold forging products by multistage former working. The approach is based on knowledge-based rules, and a process knowledge base consisting of design rules is built. Knowledge for the system is formulated from plasticity theories, empirical results and empirical knowledge of field experts. Programs for the system have been written in AutoLISP for AutoCAD with a personal computer. An attempt is made to link programs incorporating a number of expert design rules with the process variables obtained by commercial FEM software, DEFORM and ANSYS, to form a useful package. The system is composed of three main modules and five submodules. The process planning and die design module considers several factors, such as the complexities of preform geometry, punch and die profiles, specifications of available multiformers, and the availability of standard parts. The system uses 2D geometry recognition and is integrated with the technology of process planning, die design, and CAE analysis. The standardisation of die parts for wheel bolts requiring a cold forging process is described. The system developed makes it possible to design and manufacture quasi-axisymmetric cold forging products more efficiently.     

Feature-Based Parametric Design of a Gating System for a Die-Casting Die

This paper presents a semi-automated approach for designing the gating system of a die-casting die. This approach combines the P-Q 2 technique and feature-based parametric design for achieving the automatic generation of the geometries for the gating system. It also enables users to integrate their expertise in the design at an early stage. User-defined gating features are pre-defined and stored in a gating library, and are then retrieved from the library and applied to the gating part with the desired parameters and locations during the design process. Algorithms based on the P-Q 2 technique are proposed for calculating the related parameters of the gating system. A prototype design has been developed using this approach, and the system is able to shorten the time for constructing the 3D geometries of the gating elements such as the gate, runner, overflow, shot sleeve, sprue, etc.     

基于Web的模具协同设计系统的研究与应用

分析了模具协同设计系统的需求特点,构建了模具协同设计系统的体系结构,并详细定义了模具协同设计系统的功能组成。在此基础上,开发了模具协同设计原型系统,并以多工位级进模协同设计过程为例,对系统进行了验证。     

汽车消声器封头复合模具设计

汽车消声器封头是典型的带凸缘旋转体拉深件,通过分析零件和工艺特点,设计了一套合理可行的冲压复合模具。     

面向并行设计的模具装配模型描述

通过对传统模具ＣＡＤ系统的分析及目前并行工程等先进制造理论对新型模具ＣＡＤ系统的要求,基于一般模具设计过程及ＥＸＰＲＥＳＳ－Ｇ的研究,提出了面向并行设计的模具装配描述模型,同时讨论了已有装配模型的不足。基于此模具装配模型,解释了实现并行设计的方法与过程     

硅橡胶模具制作及浇注工艺的探讨

阐述了硅橡胶模具的制造方法和步骤。并对制作硅橡胶模具时，母样在模具中的放置、浇注系统设计、排气孔设计及制件浇注工艺进行了探讨总结。这些总结对于保证制件的成品率具有一定的应用价值。     

Development of a die design system for die casting

This paper presents a research work of a computer-aided die design system for die casting. The proposed system consists of seven distinct modules. Through these modules, the die designers are able to create a die casting die from a product part model. It is a user-friendly system that allows both experienced and novice die designers to easily accomplish the task of die design.The practical goal of this research is twofold: (1) to develop a system that integrates the different stages of die design process and (2) that at the same time facilitates the editing of die casting design during or after the course of the design process. The approach undertaken in this research includes (1) feature-based and constraint-based modelling, (2) parametric design and (3) a geometric and topological information extraction technique from a B-rep model. A prototype system has been developed using this approach and the system is able to aid the automation of the die casting die design process, thus improving the efficiency and quality of, and reducing the cost of die design for die casting.     

正向热挤压凹模优化设计方法的研究

员过快是传统的正向热挤压凹模使用寿命短的主要原因，而凹模型腔表面压力分布不均是磨损过快的关键因素，以改善凹模型腔表面的压力分布为目标，研究反推法和修正的序旬二次规划法两种优化设计方法，并将优化设计所得凹模型腔同传统的凹模型腔作了比较。     

冲压模具设计中尺寸标注布置的应用实例

尺寸标注是模具设计重要实践环节,从冲压模设计尺寸标注的实际出发,讲述了冲压模具设计尺寸标注布置方法、思路、和出现的问题,实践证明效果良好,值得推广。     

Development of a Practical Blank Layout Optimisation System for Stamping Die Design

Blank layout is one of the most important processes in stamping die design. As the major cost in sheet metal stamping is the material cost, any efforts to minimise the scrap may result in substantial savings not only in strip material, but also in overall production. This paper is mainly targeted at establishing a practical blank layout optimisation system for stamp ing die by using AutoCAD’s ObjectARX toolkit. The basic principles of blank layout optimisation are first described, and then the general structure of the system is proposed. Not only a suitable algorithm for layout calculation, but also the manufacturing requirements and user operation are fully considered in this system. Finally, an algorithm for blank shape offsetting is proposed to solve the problem of self-intersection in offset curves, and the traditional ‘1-step tranzlation’ algorithm for the calculation of layout parameters is improved to eliminate the conflict between precision and efficiency in the layout optimisation.     

基于数值分析的轮胎胶料共挤出口模设计

在轮胎胶料挤出生产中,口模的结构对共挤出产品的质量起着关键的作用,但在实际生产中,共挤出口模的设计主要依靠经验,口模设计质量的控制需要经过多次试模和修模。采用流体计算软件Polyflow进行轮胎胶料(TWD40/FS10)的共挤成型过程的三维数值模拟,分析共挤出过程中的速度、压力分布以及胶料熔体的流动情况,并通过试验验证模拟的可行性。针对初始口模设计的不足,提出增加窄缝区域高度和扩充口模入口的方法,有效解决初始模具设计中速度分布不均的问题,改善了口模中熔体的流动,提高了挤出质量,同时还降低了挤出过程中的能耗。利用数值方法可对共挤出口模结构进行设计,提出的口模设计方法可以对同类轮胎胶料共挤出口模结构的设计提供指     

工业设计中油漆配色专家系统的建构

介绍了如何将人工神经网络与专家系统相结合，以开发出用于工业设计中色彩设计的油漆配色专家系统，重点论述了系统的设计思想、理论基础和基本结构。     

冷冲模快速设计技术的研究与开发

研究了冷冲模设计中刃口尺寸的自动标注、排样优化以及标题栏的定制等关键技术,采用交互式和参数化设计的方法,依托AutoCAD平台,利用VB技术,开发了冷冲模快速设计与管理系统,提高了冷冲模的设计效率。     

控制系统的冗余策略和实现准则

结合过程控制系统特点和冗余要求 ,分析了冗余控制系统中典型部件基于对象的故障模型 ,按冗余部件之间的故障关联度进行了故障分类 ,推导了实际冗余部件的失效率计算方法 ,并在此基础上提出了基于对象故障模型的冗余策略和冗余实现准则     

大型机载信息系统结构总体设计初探

描述大型机载信息系统结构总体设计,分析机载信息系统结构总体设计的主要工作流程和研制阶段工作要点,概述结构总体方案设计和结构总体详细设计阶段的重点工作;机载信息系统的通用化、模块化、系列化设计是工程结构总体设计中的重要内容;简要叙述了主要的试验验证项目。     

大型模锻液压机平衡系统原理及其理论研究

滑块平衡系统是大型模锻液压机关键部件,其作用是避免滑块在工作状态下产生倾斜,从而保证上下模具准确压合,确保工件质量,对滑块运行精度及产品质量的保证具有决定性作用。液压机工作过程中,偏心力矩是未知的,如何由实测的滑块四角位移差值确定所需的平衡力,成为一个关键技术与理论难题。为此,提出力偶调平、位置控制平衡系统的新概念及其工作原理,即在滑块四角布置四组柱塞平衡缸,并由高精度位移传感器对滑块四角行程进行实时监测,以控制相应缸组加压与泄压。建立了其参数化力学模型,推导出滑块四角位移差值与所需平衡力之间的函数关系式,并绘制出相关曲线,可以在已知滑块四角位移差值的条件下,为实际加工过程中平衡力的控制提供理论依据,也可为同类型液压机滑块同步平衡系统的设计提供理论参考。