机械外文翻译文献翻译注塑成型的模具设计工具

机械外文 翻译 阿房宫赋翻译下载德汉翻译pdf阿房宫赋翻译下载阿房宫赋翻译下载翻译理论.doc 文献翻译注塑成型的模具设计工具 机械专业中英文文献翻译 英文原文 Session VA4 I ntelligent Mold Design Tool For Plastic Injection Molding Jagannath Yammada, Terrence L. Chambers, Suren N. Dwivedi Department of Mechanical Engineering University of Louisiana at Lafayette Abstract Plastic Injection molding is one of the most popular manufacturing processes for making thermoplastic products, and mold design is a key aspect of the process. Design of molds requires knowledge, expertise and most importantly experience in the field. When one of these is lacking, selection of an appropriate mold for manufacturing a plastic component is done on a trial-and-error basis. This increases the cost of production and introduces inconsistencies in the design. This paper describes the development of an intelligent mold design tool. The tool captures knowledge about the mold design process and represents the knowledge in logical fashion. The knowledge acquired will be deterministic and non-deterministic information about the mold design process. Once developed the mold design tool will guide the user in selecting an appropriate mold for his plastic part based on various client specifications. Introduction The plastic injection molding process demands knowledge, expertise and, most important, experience for its successful implementation. Often it is the molding parameters that control the efficiency of the process. Effectively controlling and optimizing these parameters during themanufacturing process can achieve consistency, which takes the form of part quality and part cost. The level of experience of the manufacturer(s) determines how effectively the process parameters are controlled. This sometimes leads to inconsistency introduced by human error. There is also the case where there is inexperience, shortage of time, resources and little scope for innovation. Knowledge-based engineering provides a feasible solution to all these problems by creating what is called an “intelligent model” of the problem. 1 IKEM Intelligent Knowledge based Engineering modules for the plastic injection molding process (IKEM) is a software technology that is a step ahead of the concurrent engineering and CAD/CAM systems. It integrates current knowledge about the design and manufacturing processes and helps to reduce several man-hours by reducing engineering changes in the design phase of product development by giving users instruction about various design aspects. The system will be used for injection molding design, design iterations, and process integration. The current process consists of many manual computations, CAD graphical constructions, and 机械专业中英文文献翻译 experience attained from previous projects. Once the engineer completes the design, it will be evaluated for performance. The IKEM project has been divided into three major modules. 1. The cost estimation module 2. The mold design module 3. The Manufacturing module Input to the IKEM system is of two forms. Input in the form of a CAD model (Pro-E file) and input given at the User Interface form. Figure 1 illustrates the kind of input that goes into each module and the output given to the user. Figure 1. Organization of the IKEM Project 2 Intelligent Mold Design Tool The mold design tool in its basic form is a Visual Basic application taking input from a text file that contains information about the part and a User Input form. The text file contains information about the part geometry parsed from a Pro/E information file. The input is used to estimate the dimensions of mold and variousother features. 2.1 Literature Review Design of molds is another stage of the injection molding process where the experience of an engineer largely helps automate the process and increase its efficiency. The issue that needs attention is the time that goes into designing the molds. Often, design engineers refer to tables and standard handbooks while designing a mold, which consumes lot of time. Also, a great deal of time goes into modeling components of the mold in standard CAD software. Differen researchers have dealt with the issue of reducing the time it takes to design the mold in different ways. Koelsch and James have employed group technology techniques to reduce the mold design time. A unique coding system that groups a class of injection molded parts, and the tooling required ininjection molding is developed which is general and can be applied to other product lines. A software system to implement the coding system has also been developed. Attempts were also directed towards the automation of the mold design process by capturing experience and knowledge of engineers in the field. The development of a concurrent mold design system is one such approach that attempts to develop a systematic methodology for injection mold design 机械专业中英文文献翻译 processes in a concurrent engineering environment. The objective of their research was to develop a mold development process that facilitates concurrent engineering-based practice, and to develop a knowledge-based design aid for injection molding mold design that accommodates manufacturability concerns, as well as product requirements. Researchers have been trying to automate the mold design process either by capturing only the deterministic information on the mold design process or the non-deterministic information, in various ways. This research uniquely attempts to develop a mold design application that captures information in both forms; deterministic and non-deterministic. 2.2 Approach Adopted In order to develop an intelligent mold design tool, the conventional method of designing molds is studied. The application developer and the design engineer work together in designing a mold for a particular plastic part. During this time, the approach adopted by the engineer to select the mold base is closely observed and aspects of the selection process that require his knowledge/experience are identified. Also, there will be times when the engineer will refer to tables and handbooks in order to standardize his selection process. This time consuming process is also recorded to incorporate it later in the application. Formulating the problem for the application in terms of inputs and outputs is the next stage. This involves defining what information about the mold layout is most required for the user and also the minimum number of inputs that can be taken from him to give those outputs. In injection molding, the polymer melt at high temperature is injected into the mold under high pressure [1]. Thus, the mold material needs to have thermal and mechanical properties capable of withstanding the temperatures and pressures of the molding cycle. The focus of many studies has been to create the injection mold directly by a rapid prototyping (RP) process. By eliminating multiple steps, this method of tooling holds the best promise of reducing the time and cost needed to create low-volume quantities of parts in a production material. The potential of integrating injection molding with RP technologies has been demonstrated many times. The properties of RP molds are very different from those of traditional metal molds. The key differences are the properties of thermal conductivity and elastic modulus (rigidity). For example, the polymers used in RP-fabricated stereolithography (SL) molds have a thermal conductivity that is less than one thousandth that of an aluminum tool. In using RP technologies to create molds, the entire mold design and injection-molding process parameters need to be modi,ed and optimized from traditional methodologies due to the completely different tool material. However, there is still not a fundamental understanding of how the modi,cations to the mold tooling method and material impact both the mold design and the injection molding process parameters. One cannot obtain reasonable results by simply changing a few material properties in current models. Also, using traditional approaches when making actual parts may be generating sub-optimal results. So there is a dire need to study the interaction between the rapid tooling (RT) process and material and injection molding, so as to establish the mold design criteria and techniques for an RT-oriented injection molding process. In addition, computer simulation is an effective approach for predicting the quality of molded parts. Commercially available simulation packages of the traditional injection molding process have now become routine tools of the mold designer and process engineer [2]. Unfortunately, current simulation programs for conventional injection molding are no longer applicable to RP 机械专业中英文文献翻译 molds, because of the dramatically dissimilar tool material. For instance, in using the existing simulation software with aluminum and SL molds and comparing with experimental results, though the simulation values of part distortion are reasonable for the aluminum mold, results are unacceptable, with the error exceeding 50%. The distortion during injection molding is due to shrinkage and warpage of the plastic part, as well as the mold. For ordinarily molds, the main factor is the shrinkage and warpage of the plastic part, which is modeled accurately in current simulations. But for RP molds, the distortion of the mold has potentially more in,uence, which have been neglected in current models. For instance, [3] used a simple three-step simulation process to consider the mold distortion, which had too much deviation. In this paper, based on the above analysis, a new simulation system for RP molds is developed. The proposed system focuses on predicting part distortion, which is dominating defect in RP-molded parts. The developed simulation can be applied as an evaluation tool for RP mold design and process optimization. Our simulation system is veri,ed by an experimental example. Although many materials are available for use in RP technologies, we concentrate on using stereolithography (SL), the original RP technology, to create polymer molds. The SL process uses photopolymer and laser energy to build a part layer by layer. Using SL takes advantage of both the commercial dominance of SL in the RP industry and the subsequent expertise base that has been developed for creating accurate, high-quality parts. Until recently, SL was primarily used to create physical models for visual inspection and form-,t studies with very limited functional applications. However, the newer generation stereolithographic photopolymers have improved dimensional, mechanical and thermal properties making it possible to use them for actual functional molds. Based on the information gathered in the mold design exercise, the conventions followed by the engineer are transformed into if-then rules. Decision tables are used to account for all possible cases that arise when dealing with a particular aspect of the mold design process. The rules so framed are then organized into modules interacting with each other, using an application development environment. Finally the application is tested for its validity when it comes to designing molds for plastic parts manufactured in the industry. 2.3 Selection of Appropriate Mold Base Typically, selection of appropriate mold base for manufacturing a plastic part involves Estimating the number of cavities The number of cavities is decided depending on the number of parts required within a given time. There are also other issues like the plasticizing capacity of the machine, reject rate etc that affect the number of cavities to be present in the mold base. Deciding on the presence of inserts and their dimensions Inserts facilitate the reusability of the mold base and therefore help in reducing cost of manufacturing. When it comes to selecting the dimensions and the number, a decision is made depending on the reusability of existing old inserts and cost of ordering new ones. Determining the size and location of runners The runner size depends on the material being molded. Although there are other considerations material properties determines the channel size required for its flow. Location of runners mainly depends on the topology of runners being used. Though a circular runner system is always preferable, the branched runner system that avoids runner balancing is the one most widely used. Determining the diameter of sprue The diameter of the sprue is decided based on the size of the mold, number of cavities, or the 机械专业中英文文献翻译 amount of plastic that is to be filled within a given time. Locating gates Plastic enters the cavity at a point where it can uniformly fill the cavity. A gate can be located at any point on the perimeter of a circular cavity but has to enter at the midsection when it comes to filling rectangular cavities. Determining the size and location of water lines Water lines are located at standard distances form each other and from any wall in the mold. The convention is not to locate a waterline within one diameter range on the mold wall. Deciding mold dimensions based on above conclusions Based on all the above decisions the approximate mold dimensions can be estimated and rounded off to the nearest catalog number. Considering all the above aspects before even modeling the mold base reduces the cost and time that go into redesigning. The emergence of mold can be traced back thousands of years ago, pottery and bronze foundry, but the large-scale use is with the rise of modern industry and developed.The 19th century, with the arms industry (gun's shell), watch industry, radio industry, dies are widely used. After World War II, with the rapid development of world economy, it became a mass production of household appliances, automobiles, electronic equipment, cameras, watches and other parts the best way. From a global perspective, when the United States in the forefront of stamping technology - many die of advanced technologies, such as simple mold, high efficiency, mold, die and stamping the high life automation, mostly originated in the United States; and Switzerland, fine blanking, cold in Germany extrusion technology, plastic processing of the Soviet Union are at the world advanced. 0's, mold industry focus is based on subscriber demand, production can meet the product requirements of the mold. Multi-die design rule of thumb, reference has been drawing and perceptual knowledge, on the design of mold parts of a lack of real understanding of function. From 1955 to 1965, is the pressure processing of exploration and development of the times - the main components of the mold and the stress state of the function of a mathematical sub-bridge, and to continue to apply to on-site practical knowledge to make stamping technology in all aspects of a leap in development. The result is summarized mold design principles, and makes the pressure machine, stamping materials, processing methods, plum with a structure, mold materials, mold manufacturing method, the field of automation devices, a new look to the practical direction of advance, so that pressing processing apparatus capable of producing quality products from the first stage. Into the 70's to high speed, launch technology, precision, security, development of the second stage. Continue to emerge in this process a variety of high efficiency, business life, high-precision multi-functional automatic school to help with. Represented by the number of working places as much as other progressive die and dozens of multi-station transfer station module. On this basis, has developed both a continuous pressing station there are more slide forming station of the press - bending machine. In the meantime, the Japanese stand to the world's largest - the mold into the micron-level precision, die life, alloy tool steel mold has reached tens of millions of times, carbide steel mold to each of hundreds of millions of times p minutes for stamping the number of small presses usually 200 to 300, up to 1200 times to 1500 times. In the meantime, in order to meet product updates quickly, with the short duration (such as cars modified, refurbished toys, etc.) need a variety of economic-type mold, such as zinc alloy die down, polyurethane rubber mold, die steel skin, also has been very great development. 机械专业中英文文献翻译 From the mid-70s so far can be said that computer-aided design, supporting the continuous development of manufacturing technology of the times. With the precision and complexity of mold rising, accelerating the production cycle, the mold industry, the quality of equipment and personnel are required to improve. Rely on common processing equipment, their experience and skills can not meet the needs of mold. Since the 90's, mechanical and electronic technologies in close connection with the development of NC machine tools, such as CNC wire cutting machine, CNC EDM, CNC milling, CNC coordinate grinding machine and so on. The use of computer automatic programming, control CNC machine tools to improve the efficiency in the use and scope. In recent years, has developed a computer to time-sharing by the way a group of direct management and control of CNC machine tools NNC system. With the development of computer technology, computers have gradually into the mold in all areas, including design, manufacturing and management. International Association for the Study of production forecasts to 2000, as a means of links between design and manufacturing drawings will lose its primary role. Automatic Design of die most fundamental point is to establish the mold standard and design standards. To get rid of the people of the past, and practical experience to judge the composition of the design center, we must take past experiences and ways of thinking, for series, numerical value, the number of type-based, as the design criteria to the computer store. Components are dry because of mold constitutes a million other differences, to come up with a can adapt to various parts of the design software almost impossible. But some products do not change the shape of parts, mold structure has certain rules, can be summed up for the automatic design of software. If a Japanese company's CDM system for progressive die design and manufacturing, including the importation of parts of the figure, rough start, strip layout, determine the size and standard templates, assembly drawing and parts, the output NC program (for CNC machining Center and line cutting program), etc., used in 20% of the time by hand, reduce their working hours to 35 hours; from Japan in the early 80s will be three-dimensional cad / cam system for automotive panel die. Currently, the physical parts scanning input, map lines and data input, geometric form, display, graphics, annotations and the data is automatically programmed, resulting in effective control machine tool control system of post-processing documents have reached a high level; computer Simulation (CAE) technology has made some achievements.At high levels, CAD / CAM / CAE integration, that data is integrated, can transmit information directly with each other. Achieve network. Present.Only a few foreign manufacturers can do it. 2.4 Formulation of the Problem Based on issues that require human knowledge/experience, and aspects of mold design that consume time referring to tables, data sheets etc., the problem for developing the application is defined as shown in Figure 2. 机械专业中英文文献翻译 While most of the input, like the number of cavities, cavity image dimensions, cycle time are based on the client specifications, other input like the plasticizing capacity, shots per minute etc., can be obtained from the machine specifications. The output of the application contains mold dimensions and other information, which clearly helps in selecting the standard mold base from catalogs. Apart from the input and output, the Figure 2 also shows the various modules that produce the final output. With mold components, with high efficiency, good quality, low cost, saving energy and raw materials and a series of advantages, with the mold workpieces possess high accuracy, high complexity, high consistency, high productivity and low consumption , other manufacturing methods can not match. Have already become an important means of industrial production and technological development. The development of modern industrial and technological level depends largely on the level of industrial development die, so die industry to national economic and social development will play an increasing role.March 1989 the State Council promulgated "on the current industrial policy decision points" in the mold as the machinery industry transformation sequence of the first, production and capital construction of the second sequence (after the large-scale power generation equipment and the corresponding power transmission equipment), establish tooling industry in an important position in the national economy.Since 1997, they have to mold and its processing technology and equipment included in the "current national focus on encouraging the development of industries, products and technologies catalog" and "to encourage foreign investment industry directory."Approved by the State Council, from 1997 to 2000, more than 80 professional mold factory owned 70% VAT refund of preferential policies to support mold industry. All these have fully demonstrated the development of the State Council and state departments tooling industry attention and support.Mold around the world about the current annual output of 60 billion U.S. dollars, Japan, the United States and other industrialized countries die of industrial output value of more than machine tool industry, beginning in 1997, China's industrial output value has exceeded the mold machine tool industry output. 机械专业中英文文献翻译 According to statistics, home appliances, toys and other light industries, nearly 90% of the parts are integrated with production of chopsticks; in aircraft, automobiles, agricultural machinery and radio industries, the proportion exceeded 60%.Such as aircraft manufacturing, the use of a certain type of fighter dies more than 30,000 units, of which the host 8000 sets, 2000 sets of engines, auxiliary 20 000 sets. From the output of view, since the 80's, the United States, Japan and other industrialized countries die industry output value has exceeded the machine tool industry, and there are still rising.Production technology, according to the International Association predicts that in 2000, the product best pieces of rough 75%, 50% will be finished mold completed; metals, plastics, ceramics, rubber, building materials and other industrial products, most of the mold will be completed in more than 50% metal plates, more than 80% of all plastic products, especially through the mold into. 2.5 Framing rules At this stage, the expert’s knowledge is represented in the form of multiple If-Then statements. The rules may be representations of both qualitative and quantitative knowledge. By qualitative knowledge, we mean deterministic information about a problem that can be solved computationally. By qualitative we mean information that is not deterministic, but merely followed as a rule based on previous cases where the rule has worked. A typical rule is illustrated below: If Material = “Acetal” And Runner Length <= 3 And Runner Length > 0 Then Runner Diameter =0.062 End If When framing the rules it is important that we represent the information in a compact way while avoiding redundancy, incompleteness and inconsistency. Decision tables help take care of all the above concerns by checking for redundancy and comprehensive expression of the problem statement. As an example, in the process of selecting an appropriate mold base, the size of mold base depends on the number of cavities and inserts. To ensure that all possible combinations of cavities and inserts have been considered we use a decision table and subsequently use the decision table to frame rules. Table1 shows more than one case where the mold dimensions are the same. 机械专业中英文文献翻译 The case where the number of cavities is one and the number of inserts is one has the same mold dimensions as the case where the number of cavities is two and four. The three cases can be reduced to one single rule: If Number Of Inserts=1 Then Mold Width = (Insert Width + 2) Mold Length = (Insert Length + 2) Mold Thickness = Insert Thickness End If The rules are arranged in modular fashion using a standard programming language for the sake of convenience and clarity. Each module generates a set of outputs, which would be inputs for other modules. 2.6 Testing the applicatio The intelligent mold design application is validated using various test cases. For each case the part information, mold information and the machine information are varied and a human expert validates the results of feeding this info into the application. Table 2 shows one such test case where the part requires two cavities and there are no inserts present. The application gives the approximate mold dimensions, runner dimension, sprue dimension and runner length based on the cavity image dimensions and other information. 机械专业中英文文献翻译 Table 2. Typical test case showing program input and output. The mold dimensions obtained are very close to a typical human expert design for the test case but do not suggest explicitly the use of a standard mold base, like a specific mold from the D-M-E mold base catalog. The mold dimensions are however useful in selecting appropriate mold base from the mold catalogs. The runner dimensions are based on the material being used and therefore are limited to a specific range of shot size. 3 Summary This paper presents the approach adopted towards developing an intelligent mold design application that performs mold base selection based on user input. The knowledge acquisition process is done by first designing a mold base in close consultation with an industry expert and also by collecting deterministic information from hand books and data sheets. The collected information, which can be both qualitative and quantitative knowledge about the mold selection process, is represented in the form of rules arranged in different modules. Decision tables are used to reduce the size of rule base and make the rule base comprehensive in the problem domain. The application developed using the rules in different modules is then tested for its validity when it comes to selecting appropriate mold bases for plastic parts manufactured in the industry 译文 、 机械专业中英文文献翻译 中文翻译 原文题目 Intelligent Mold Design Tool For Plastic Injection Molding 作者 Jagannath Yammada, Terrence L. Chambers, Suren N. Dwived 译名 加甘纳斯?亚玛达，特伦斯 L 钱伯斯和苏伦N德维韦迪 国籍 美国 原文出处 Submitted to ASME/JDSMC Special Issue on Sensor 摘要 注塑成型是一个生产热塑性塑料制品最流行的制造工艺，而模具设计是这个过程的一个重要方面。模具设计需要专业的知识、技能，最重要的是拥有该领域的经验。三者缺一不可。生产塑料组件需要选择恰当的模具，如果缺乏其中之一，这种选择就得在反复试验的基础上进行。这会增加生产成本，并造成设计上的不一致。 本文介绍了智能模具设计工具的发展。该工具捕获模具设计过程的知识，并且以符合逻辑的方式将这些知识反映出来。所获得的知识将是确定性的，但模具设计过程中的信息是非确定的。一旦开发了模具设计工具，它将指导使用者根据不同客户的要求，为其塑料零件选择合适的模具。 导言 注塑成型工艺过程需要专业的知识、技能，最重要的是需要它成功的实践经验。通常是工艺参数控制过程的效率。在制造过程中，有效地控制和优化这些参数能实现一致性，这种一致性会在零件质量和零件成本上表现出来的问题。 1 智能化工程模块注塑成型工艺(IKEM) 基于知识的智能化工程模块的注塑成型工艺(IKEM)是一种软件技术，它领先于并行工程和CAD / CAM系统。它集成工程的设计和制造工艺的最新知识，给用户各种设计方面的指示，通过减少在产品开发设计阶段的工程变更，有助于减少一些工时。该系统将用于注塑设计，设计迭代和流程整合。目前的过程由许多手工计算、CAD图形结构和从以前项目取得的经验三部分组成。一旦工程师完成设计，这将是性能评估。 该IKEM项目已分为三大模块。 (1) 费用估算模块 (2) 模具设计模块 (3) 生产模块 IKEM系统有两种形式输入。在一个CAD模型的形式(Pro/E文件)下输入，和在给出的用户界面形式下输入。图1-1说明了那种进入每个模块的输入形式和用户输出形式。 制造商的经验水平将决定如何有效地控制工艺参数。有时这就导致人为错误引起的不一致性。还有经验不足，时间、资源短缺和创新的空间不大的情况。通过创造所谓的“智能模型”的问题，工程学知识提供了一个可行的 方案 气瓶 现场处置方案 .pdf气瓶 现场处置方案 .doc见习基地管理方案.doc关于群访事件的化解方案建筑工地扬尘治理专项方案下载 去解决所有 机械专业中英文文献翻译 1在它的基本形式中模具设计工具是一个从文本文件中提取输入的Visual Basic应用程序，这种文本文件包含关于零件和用户输入程序。该文本文件包含来自Pro/E的一个信息文件的零件的几何解析。输入是用来估测模具得尺寸和其它各种特性。 2.1 文献回顾 模具设计的是另一种注塑成型过程的阶段，有经验的工程师在很大程度上有助于自动化进程，提高其效率。这个问题需要注意的是深入研究设计模具的时间。通常情况下，当设计工程师设计模具时，他们会参阅表格和 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 手册，这会消耗大量的时间。另外，在标准的CAD软件中需要大量的时间去考虑模具的建模组件。不同的研究人员已经解决了缩短用不同的方式来设计模具所花费的时间的问题。凯尔奇和詹姆斯采用成组技术来减少模具设计时间。聚合一类注塑成型件的独特的编码系统和在注射模具中所需的工具已开发，它可以适用于其它产品生产线。实施编码系统的软件系统也已经被开发。通过获取在这方面领域的工程师的经验和知识，尝试直接使模具设计过程的自动化。并行模具设计系统的研究开发就是这样的一个过程，在并行工程环境中试图制定一个系统的注塑模具设计流程。他们的研究目标是研制一个有利于并行工程实践的模具开发的进程，和研制开发一个以知识为基础的为注塑模具设计提供工艺问题和产品要求的辅助设计。 通过各种方式获取关于模具设计过程的确定信息和不确定信息，研究人员一直试图使模具设计流程自动化。这个研究试图研制开发一个独特的模具设计应用程序，它一确定性和不确定性两种形式获取信息。 2.2 采用的方法 为了发展智能模具设计工具，传统的模具设计方法在被研究。应用程序开发人员和设计工程师合作设计一种特定塑料零件的模具。在此期间，被工程师采纳用来选择模底座的方法正在被地密切关注和筛选过程的各个方面，需要他的知识经验来确定。此外，有时候工程师将参考图表和手册以规范其甄选过程。这耗费时间的过程，稍后也被 记录 混凝土 养护记录下载土方回填监理旁站记录免费下载集备记录下载集备记录下载集备记录下载 在应用程序中。 系统的阐述依据输入和输出的应用程序是下一阶段。这涉及到如何定义什么养的模具布 机械专业中英文文献翻译 局信息是用户最需要的，也是他输入最少却得到相同的输出。 在注塑,聚合物熔体在高温注入模具在高压力[1]。因此,模具材料需要有热、力学性能能够 受的温度和压力成型周期。许多研究的焦点已经创 建注塑模具直接由一个快速原型(RP)过程。通过消除多个步骤,这种方法的工具拥有最好的承诺,减少时间和成本需要创建少量数量的零件在生产材料。潜在的整合注塑与RP技术已经证明很多次。属性的RP模具非常不同传统的金属模具。关键的不同之处在于导热性能和弹性模量(刚性)。例如,聚合物用于rp装配式解决(SL)模具有一个热导,小于一千的铝工具。在利用RP技术来创建模具,整个模具设计和注塑成型工艺参数需要修改和优化从传统方法由于完全不同的工具材料。然而,目前还没有一个基本的了解修改的模具加工方法和材料都影响模具设计和注塑工艺参数。一个人不能获得合理的结果,只要改变一些材料属性在当前的模型。同时,使用传统方法进行实际零件可能产生次优的结果。所以有一个可怕的需要研究之间的交互(RT)快速模具和注塑工艺及材料,从而建立模具设计标准和技术对于一个RT导向的注射成型工艺。 此外,计算机仿真是一种有效的方法来预测注塑件的质量。商用仿真软件包的传统注塑工艺现在已经成为常规工具的模具设计师和工艺工程师[2]。不幸的是,当前的仿真程序对常规注塑不再适用于RP模具,由于显著不同的工具材料。例如,在使用现有的仿真软件与铝和SL模具和比较实验结果,尽管模拟值的部分失真是合理的铝模,结果是不可接受的,误差超过50%。在注射成型的变形是由于收缩和翘曲的塑料部分,以及模具。对于一般模具,主要因素是收缩和翘曲的塑料部分,这是在当前模拟精确模拟。但对RP模具,模具的变形可能更多的影响力,而忽视了在当前的模型。例如,[3]使用一个简单的三步模拟过程考虑模具变形,它有太多的偏差。 本文基于上述 分析 定性数据统计分析pdf销售业绩分析模板建筑结构震害分析销售进度分析表京东商城竞争战略分析 ,一个新的仿真系统开发模具RP。拟议的系统着重于预测部分失真,这是控制缺陷在rp成型零件。发达的模拟可以应用作为评价工具,模具设计和过程优化卢比。我们的仿真系统是一个实验例子验证了。 尽管很多材料都可以使用在RP技术,我们专注于使用解决(SL),原来的RP技术,创建聚合物模具。SL流程使用光敏聚合物和激光能量,一层一层地建造一个部分。使用SL利用两个商业的主导地位在RP SL工业和随后的专业知识基础,已经开发,建立准确、高质量的零件。直到最近,SL主要是用于创建物理模型进行目视检查和壳式研究非常有限的功能的应用程序。然而,新一代stereolithographic photopolymers有改善空间,机械和热性能使它可以使用他们的实际功能的模具。 根据在模具设计工作中收集到的信息，由工程师遵循的公约被转化为if - then规则。决策表是用来解释各种可能出现的情况，它们是当处理模具设计工程中某一特定的方面所提出的。这样被制定规则，然后被组织在相互交融的模块中，使用应用程序开发环境。最后，应用程序是检验其正确性，当涉及到为塑料零件设计模具在工业生产中。 模具的出现可以追溯到几千年前的陶器和青铜器铸造，但其大规模使用却是随着现代工业的掘起而发展起来的。 19世纪，随着军火工业(枪炮的弹壳)、钟表工业、无线电工业的发展，冲模得到广泛使用。二次大战后，随着世界经济的飞速发展，它又成了大量生产家用电器、汽车、电子仪器、照相机、钟表等零件的最佳方式。从世界范围看，当时美国的冲压技术走在前列——许多模具先进技术，如简易模具、高效率模具、高寿命模具和冲压自动化技术，大多起源于美国;而瑞士的精冲、德国的冷挤压技术，苏联对塑性加工的研究也处于世界先进行列。50年代，模具行业工作重点是根据订户的要求，制作能满足产品要求的模具。模具设计多凭经验，参考已有图纸和感性认识，对所设计模具零件的机能缺乏真切了解。从1955年到1965年，是压力加工的探索和开发时代——对模具主要零部件的机能和受力状态进行了数学分桥，并把 机械专业中英文文献翻译 这些知识不断应用于现场实际，使得冲压技术在各方面有飞跃的发展。其结果是归纳出模具设计原则，并使得压力机械、冲压材料、加工方法、梅具结构、模具材料、模具制造方法、自动化装置等领域面貌一新，并向实用化的方向推进，从而使冲压加工从仪能生产优良产品的第一阶段。 进入70年代向高速化、启动化、精密化、安全化发展的第二阶段。在这个过程中不断涌现各种高效率、商寿命、高精度助多功能自动校具。其代表是多达别多个工位的级进模和十几个工位的多工位传递模。在此基础上又发展出既有连续冲压工位又有多滑块成形工位的压力机—弯曲机。在此期间，日本站到了世界最前列——其模具加工精度进入了微米级，模具寿命，合金工具钢制造的模具达到了几千万次，硬质合金钢制造的模具达到了几亿次p每分钟冲压次数，小型压力机通常为200至300次，最高为1200次至1500次。在此期间，为了适应产品更新快、用期短(如汽车改型、玩具翻新等)的需要，各种经济型模具，如锌落合金模具、聚氨酯橡胶模具、钢皮冲模等也得到了很大发展。 从70年代中期至今可以说是计算机辅助设计、辅助制造技术不断发展的时代。随着模具加工精度与复杂性不断提高，生产周期不断加快，模具业对设备和人员素质的要求也不断提高。依靠普通加工设备，凭经验和手艺越来越不能满足模具生产的需要。90年代以来，机械技术和电子技术紧密结合，发展了NC机床，如数控线切割机床、数控电火花机床、数控铣床、数控坐标磨床等。而采用电子计算机自动编程、控制的CNC机床提高了数控机床的使用效率和范围。近年来又发展出由一台计算机以分时的方式直接管理和控制一群数控机床的NNC系统。 随着计算机技术的发展，计算机也逐步进入模具生产的各个领域，包括设计、制造、管理等。国际生产研究协会预测，到2000年，作为设计和制造之间联系手段的图纸将失去其主要作用。模具自动设计的最根本点是必须确立模具零件标准及设计标准。要摆脱过去以人的思考判断和实际经验为中心所组成的设计方法，就必须把过去的经验和思考方法，进行系列化、数值化、数式化，作为设计准则储存到计算机中。因为模具构成元件也干差万别，要搞出一个能适应各种零件的设计软件几乎不可能。但是有些产品的零件形状变化不大，模具结构有一定的规律，放可总结归纳，为自动设计提供软件。如日本某公司的CDM系统用于级进模设计与制造，其中包括零件图形输入、毛坯展开、条料排样、确定模板尺寸和标准、绘制装配图和零件图、输出NC程序(为数控加工中心和线切割编程)等，所用时间由手工的20%、工时减少到35小时;从80年代初日本就将三维的CAD,CAM系统用于汽车覆盖件模具。目前，在实体件的扫描输入，图线和数据输入，几何造形、显示、绘图、标注以及对数据的自动编程，产生效控机床控制系统的后置处理文件等方面已达到较高水平;计算机仿真(CAE)技术也取得了一定成果。在高层次上，CAD,CAM,CAE集成的，即数据是统一的，可以互相直接传输信息(实现网络化。目前(国外仅有少数厂家能够做到。 2.3 选择合适的模架 通常情况下，为制造塑料零件选择适当的模架所涉及的有: (1)估计模腔数 模腔数量的决定取决于在一定时间内所需部件的数量，像机器的塑化能力，废品率等问题也会影响到模架的模腔数量。 (2)确定镶块及其尺寸 镶块有助于模架重用，因此有助于降低生产成本。当涉及到尺寸和数量的选择，作出决定取决于现有的镶块的重用性和新的镶块的成本。 (3)确定浇道的尺寸和定位 浇道的尺寸取决于所成型的材料。尽管还有其它要考虑材料特性来决定它的浇道的尺寸供符合它的流量要求。转轮的定位，取决于所用流道的拓扑布局。虽然循环的浇道系统始终是最好的，支道系统的平衡，避免流道均衡补偿的树枝状浇道系统是一个最被广泛应用的系统。 (4)确定浇道直径 浇道直径决定于模具的尺寸，模腔的数量或在一定的时间内用来填补 机械专业中英文文献翻译 的塑料的总数。 (5)浇口的定位 塑料在某一点进入模腔，在这点可以均匀填充满模腔。浇口可以设在循环模腔的任何周围点，但当填补矩形腔时，必须从中部流进。 (6)确定供水道的的尺寸和定位 供水道之间和从模具中的任何壁上以标准的距离定位。该公约不是用一个直径范围定位水道在模具壁上。 (7)根据以上结论确定模具的尺寸 根据以上的所有结论，模具的大概尺寸可以被估计，并四舍五入至最接近的产品目录号。在模架以前，如果重新设计，考虑到以上所有方面会降低成本和减少设计时间，进入重新设计。 2.4问题的提出 建立问题，需要人的知识和经验，模具设计方面消耗的时间涉及到图表，数据表等，为开发应用程序的问题解释如图2-1所示。虽然大部分的输入如模腔数、腔的图像尺寸、周期时间，都是根据客户要求，其他输入如塑化能力、每分钟注射量等，可从机器的说明书中获得。应用程序的输出包含模具尺寸和其他资料，这显然有助于在目录中选择标准模架。除了输入和输采用模具生产零部件，具有生产效率高、质量好、成本低、节约能源和原材料等一系列优点，用模具生产制件所具备的高精度、高复杂程度、高一致性、高生产率和低消耗，是其他加工制造方法所不能比拟的。已成为当代工业生产的重要手段和工艺发展方向。现代经济的基础工业。现代工业品的发展和技术水平的提高，很大程度上取决于模具工业的发展水平，因此模具工业对国民经济和社会发展将起越来越大的作用。1989年3月国务院颁布的《关于当前产业政策要点的决定》中，把模具列为机械工业技术改造序列的第一位、生产和基本建设序列的第二位(仅次于大型发电设备及相应的输变电设备)，确立模具工业在国民经济中的重要地位。1997年以来，又相继把模具及其加工技术和设备列入了《当前国家重点鼓励发展的产业、产品和技术目录》和《鼓励外商投资产业目录》。经国务院批准，从1997年到2000年，对80多家国有专业模具厂实行增值税返还70%的优惠政策，以扶植模具工业的发展。所有这些，都充分体现了国务院和国家有关部门对发展模具工业的重视和支持。目前全世界模具年产值约为600亿美元，日、美等工业发达国家的模具工业产值已超过机床工业，从1997年开始，我国模具工业产值也超过了机床工业产值。 据统计，在家电、玩具等轻工行业，近90,的零件是综筷具生产的;在飞机、汽车、农机和无线电行业，这个比例也超过60,。例如飞机制造业，某型战斗机模具使用量超过三万套，其中主机八千套、发动机二千套、辅机二万套。从产值看，80年代以来，美、日等工业发达国家模具行业的产值已超过机床行业，并又有继续增长的趋势。据国际生产技术协会预测，到2000年，产品尽件粗加工的75%、精加工的50,将由模具完成;金属、塑料、陶瓷、橡胶、建材等工业制品大部分将由模具完成，50,以上的金属板材、80,以上的塑料都特通过模具转化成制品。 出，图2也显示了产生的最终输出的各种模块。 2.5 制定规则 在这个阶段，专家的知识可以通过多形式的“如果-那么”语句表现出来。这个规则可以是对定性和定量知识的陈述。所谓定性知识，是指一个能够解决计算问题的确定性的信息。所谓定性，是说对于不确定性的信息，而仅仅是作为在以往个案的基础上的一种已经应用的规则。一个典型的规则说明如下: 机械专业中英文文献翻译 如果材料=“缩醛”和分流道长度“<= 3， 分流道长度“>0，那么分流道直径 = 0.062 结束 当制定了规则，重要的是我们用一种严谨的方式的来表现这些信息，同时要避免重复、不完整和不一致的现象。决策表可以帮助处理上述问题，它是通过对过于冗余和广泛的问题陈述的检查实现的。比如说，在选择适当的模架的过程中，模架尺寸取决于型腔和镶件的数目。为确保所有型腔和镶件都被考虑到，我们使用了决策表，并随后用决策表来制定规则。 表2-1显示了在一个以上的情况下，模具的尺寸是相同的 情况 A: 模具宽度 =(镶块长度 + 2);模具长度=(镶块长度 + 2);模具厚度=镶块厚度。 情况 B: 模具宽度=(2*镶块宽度 + 3.5);模具长度=(镶块长度+ 2);模具厚度=镶块厚度。 情况 C: 模具宽度=(2*镶块宽度 + 3.5);模具长度=(镶块长度+ 3);模具厚度=镶块厚度。 机械专业中英文文献翻译 型腔的数目是一个，镶件的数目也是一个的情况和型腔数目是两个和四个的情况具有相同的模具尺寸，这三种情况可以归结为一个单一的规则: 如果 镶块的数目= 1，则模具宽度 =(镶块宽度 + 2)模具长度 =(镶块长度+ 2)模具厚度 = 镶块厚度 结束 相同的模具尺寸，这三种情况可以归结为一个单一的规则: 如果 镶块的数目= 1，则模具宽度 =(镶块宽度 + 2)模具长度 =(镶块长度+ 2)模具厚度 = 镶块厚度 结束 为了方便和清楚起见，用一种标准的编程语言将这些规则模块化。每个模块生成一组输出，这个输出又将是对其他模块的输入。 2.6 测试应用 通过使用各种测试案例对智能模具设计中的应用程序进行了验证。对于每一个案件的零件信息，模具和机器的信息资料种类繁多，人类专家证实了把这些信息输入到应用程序的结果。表2显示了一个这样的试验，需要两个模腔，也没有镶件的存在。应用程序提供近似的模具尺寸，执行尺寸，浇口尺寸和亚军的模腔长度基于模腔图尺寸和其他信息。 通过使用各种测试案例对智能模具设计中的应用程序进行了验证。对于每一个案件的零件信息，模具和机器的信息资料种类繁多，人类专家证实了把这些信息输入到应用程序的结果。表2显示了一个这样的试验，需要两个模腔，也没有镶件的存在。应用程序提供近似的模具尺寸，执行尺寸，浇口尺寸和亚军的模腔长度基于模腔图尺寸和其他信息。 获得的模具尺寸非常接近人类专家的一个典型设计，但并没有明确地说明了一个模具标准件的用途，就像D-M-E模具目录中的一种特定的模具。模具尺寸是基于所用材料而定的，因此它被限制在一定的范围。 3总结 本文介绍了在发展智能模具设计应用中所采用的方法，这种应用是根据用户输入进行模架选择的。获取知识的过程首先是通过与业内专家密切协商设计一种模架，也通过从旧书 机械专业中英文文献翻译 和数据表中收集确定性信息。收集到的资料，表示了在不同的模块中规则的排列形式。这些资料可定性和定量地对模具进行选择。决策表是用来减少规则库的规模，使规则库中的问题域全面。在不同的模块中使用这些规则来开发应用程序，当谈到在给业内生产的塑件选择适当的模架时就为应用程序的有效性作测试。