注塑模的参数控制型腔布局设计系统外文文献翻译、中英文翻译、外文翻译

1 一、 外文原文 A Parametric-Controlled Cavity Layout Design System for a Plastic Injection Mould M. L. H. Low and K. S. Lee Department of Mechanical Engineering, National University of Singapore, Singapore Today, the time-to-market for plastic products is becoming shorter, thus the lead time available for making the injection mould is decreasing. There is potential for timesaving in the mould design stage because a design process that is repeatable for every mould design can be standardised. This paper presents a methodology for designing the cavity layout for plastic injection moulds by controlling the geometrical parameters using a standardisation template. The standardization template for the cavity layout design consists of the configurations for the possible layouts. Each configuration of the layout design has its own layout design table of all the geometrical parameters. This standardisation template is pre-defined at the layout design level of the mould assembly design. This ensures that the required configuration can be loaded into the mould assembly design very quickly, without the need to redesign the layout. This makes it useful in technical discussions between the product designers and mould designers prior to the manufacture of the mould. Changes can be made to the 3D cavity layout design immediately during the discussions, thus saving time and avoiding miscommunication. This standardisation template for the cavity layout design can be customised easily for each mould making company to their own standards. Keywords: Cavity layout design； Geometrical parameters； Mould assembly； Plastic injection mould design； Standardisation template 1. Introduction Plastic injection moulding is a common method for the mass production of plastic parts with good tolerances. There are two main items that are required for plastic injection moulding. They are the injection-moulding machine and the injection mould. The injection-moulding machine has the mould mountedon it and provides the mechanism for molten plastic transfer from the machine to the mould, clamping the mould by the application of pressure and the ejection of the formed plastic part. The injection mould is a tool for transforming the molten plastic into the final shape and dimensional details of the plastic part. Today, as the time-to-market for plastic parts is becoming shorter, it is essential to produce the injection mould in a shorter time. Much work had been done on applying computer technologies to injection mould design and the related field. Knowledge-based systems (KBS) such as IMOLD 1,2, IKMOULD3, ESMOLD 4, the KBS of the National Cheng Kang University, Taiwan 5, the KBS of Drexel University 6, etc. were developed for injection mould design. Systems such as HyperQ/Plastic 7, CIMP 8, FIT 9, etc. are developed for the selection of plastic materials using a knowledge-based approach. Techniques have also been developed for parting design in injection moulding 1012. It has been observed that although mould-making industries are using 3D CAD software for mould design, much time is wasted in going through the same design processes for every project. There is great potential for timesaving at the mould design stage if the repeatable design processes can be standardized to avoid routine tasks. A well-organised hierarchical design tree in the mould assembly is also an important factor 13,14.However, little work has been done in controlling the parameters in the cavity layout design； thus this area will be our main focus. Although there are 2 many ways of designing the cavity layout 15,16, mould designers tend to use only conventional designs, thus there is a need to apply standardisation at the cavity layout design level. This paper presents a methodology for designing the cavity layout for plastic injection moulds by controlling the parameters based on a standardisation template. First, a well-organised mould assembly hierarchy design tree had to be established. Then, the classification of the cavity layout configuration had to be made to differentiate between those with standard configurations and those with non-standard configurations. The standard configurations will be listed in a configuration database and each configuration has its own layout design table that controls its own geometrical parameters. This standardization template is pre-defined at the layout design level of the mould assembly design. 2. Cavity Layout Design for a Plastic Injection Mould An injection mould is a tool for transforming molten plastic into the final shape and dimensional details of a plastic part. Thus, a mould contains an inverse impression of the final part. Most of the moulds are built up of two halves: the front insert and the back insert. In certain mould-making industries, the front insert is also known as the cavity and the back insert is known as the core. Figure 1 shows a front insert (cavity) and a back insert (core). Molten plastic is injected into the impression to fill it. Solidification of the molten plastic then forms the part. Figure 2 shows a simple two-plate mould assembly. 2.1 Difference Between a Single-Cavity and a Multi-Cavity Mould Very often, the impression in which molten plastic is being filled is also called the cavity. The arrangement of the cavities is called the cavity layout. When a mould contains more than one cavity, it is referred to as a multi-cavity mould. Figures 3(a) and 3(b) shows a single-cavity mould and a multi-cavity mould. A single-cavity mould is normally designed for fairly large parts such as plotter covers and television housings. For smaller parts such as hand phone covers and gears, it is always more economical to design a multi-cavity mould so that more parts can be produced per moulding cycle. Customers usually determine the number of cavities, as they have to balance the investment in the tooling against the part cost. 2.2 Multi-Cavity Layout A multi-cavity mould that produces different products at the same time is known as a family mould. However, it is not usual to design a mould with different cavities, as the cavities may not all be filled at the same time with molten plastic of the same temperature. On the other hand, a multi-cavity mould that produces the same product throughout the 3 moulding cycle can have a balanced layout or an unbalanced layout. A balanced layout is one in which the cavities are all uniformly filled at the same time under the same melt conditions 15,16. Short moulding can occur if an unbalanced layout is being used, but this can be overcome by modifying the length and cross-section of the runners (passageways for the molten plastic flow from the sprue to the cavity). Since this is not an efficient method, it is avoided where possible. Figure 4 shows a short moulding situation due to an unbalanced layout. A balanced layout can be further classified into two categories: linear and circular. A balanced linear layout can accommodate 2, 4, 8, 16, 32 etc. cavities, i.e. it follows a 2n series. A balanced circular layout can have 3, 4, 5, 6 or more cavities, but there is a limit to the number of cavities that can be accommodated in a balanced circular layout because of space constraints. Figure 5 shows the multi-cavity layouts that have been discussed. 3. The Design Approach This section presents an overview of the design approach for the development of a parametric-controlled cavity layout design system for plastic injection moulds. An effective working method of mould design involves organising the various subassemblies and components into the most appropriate hierarchy design tree. Figure 6 shows the mould assembly hierarchy design tree for the first level subassembly and components. Other subassemblies and components are assembled from the second level onwards to the nth level of the mould assembly hierarchy design tree. For this system, the focus will be made only on the “cavity layout design”. 3.1 Standardisation Procedure In order to save time in the mould design process, it is necessary to identify the features of the design that are commonly used. The design processes that are repeatable for every mould design can then be standardised. It can be seen from Fig. 7 that there are two sections that interplay in the standardization procedure for the “cavity layout design”: component assembly standardisation and cavity layout configuration standardisation. 4 3.1.1 Component Assembly Standardisation Before the cavity layout configuration can be standardised, there is a need to recognise the components and subassemblies that are repeated throughout the various cavities in the cavity layout. Figure 8 shows a detailed “cavity layout design” hierarchy design tree. The main insert subassembly (cavity) in thesecond level of the hierarchy design tree has a number of subassemblies and components that are assembled directly to it from the third level onwards of the hierarchy design tree. They can be viewed as primary components and secondary components. Primary components are present in every mould design. The secondary components are dependent on the plastic part that is to be produced, so they may or may not be present in the mould designs. As a result, putting these components and subassemblies directly under the main insert subassembly, ensures that every repeatable main insert (cavity) will inherit the same subassemblies and components from the third level onwards of the hierarchy design tree. Thus, 5 there is no need to redesign similar subassemblies and components for every cavity in the cavity layout. 3.1.2 Cavity Layout Configuration Standardisation It is necessary to study and classify the cavity layout configurations into those that are standard and those that are nonstandard. Figure 9 shows the standardisation procedure of the cavity layout configuration. A cavity layout design, can be undertaken either as a multicavity layout or a single-cavity layout, but the customers always determine this decision. A single-cavity layout is always considered as having a standard configuration. A multi-cavity mould can produce different products at the same time or the same products at the same time. A mould that produces different products at the same time is known as a family mould, which is a non-conventional design. Thus, a multicavity family mould has a non-standard configuration. A multi-cavity mould that produces the same product can contain either a balanced layout design or an unbalanced layout design. An unbalanced layout design is seldom used and, as a result, it is considered to possess a non-standard configuration. However, a balanced layout design can also encompass either a linear layout design or a circular layout design. This depends on the number of cavities that are required by the customers. It must be noted, however, that a layout design that has any other non-standard number of cavities is also classified as having a non-standard configuration. After classifying those layout designs that are standard, their detailed information can then be listed into a standardization template. This standardisation template is pre-defined in the cavity layout design level of the mould assembly design and supports all the standard configurations. This ensures that the required configuration can be loaded very quickly into the mould assembly design without the need to redesign the layout. 6 3.2 Standardisation Template It can be seen from Fig. 10 that there are two parts in the standardisation template: a configuration database and a layoutde sign table. The configuration database consists of all the standard layout configurations, and each layout configuration has its own layout design table that carries the geometrical parameters. As mould-making industries have their own standards, the configuration database can be customised to take into account those designs that are previously considered as non-standard. 3.2.1 Configuration Database A database can be used to contain the list of all the different standard configurations. The total number of configurations in this database corresponds to the number of layout configurations available in the cavity layout design level of the mould design assembly. The information listed in the database is the configuration number, type, and the number of cavities. Table 1 shows an example of a configuration database. The configuration number is the name of each of the available layout configurations with the corresponding type and number of cavities. When a particular type of layout and number of cavities is called for, the appropriate layout configuration will be loaded into the cavity layout design. 3.2.2 Layout Design Table Each standard configuration listed in the configuration database has its own layout design table. The layout design table contains the geometrical parameters of the layout configuration and is independent for every configuration. A more complex layout configuration will have more geometrical parameters to control the cavity layout. Figures 11(a) and 11(b) show the back mould plate (core plate) with a big pocket and four small pockets for assembling the same four-cavity layout. It is always more economical and easier to machine a large pocket than to machine individual smaller pockets in a block of steel. The advantages of machining a large pocket are: 7 1. More space between the cavities can be saved, thus a smaller block of steel can be used. 2. Machining time is faster for creating one large pocket compared to machining multiple small pockets. 3. Higher accuracy can be achieved for a large pocket than for multiple smaller pockets. As a result, the default values of the geometrical parameters in the layout design table results in there being no gap between the cavities. However, to make the system more flexible, the default values of the geometrical parameters can be modified to suit each mould design where necessary. 3.3 Geometrical Parameters There are three variables that establish the geometrical parameters: 1. Distances between the cavities (flexible). The distances between the cavities are listed in the layout design table and they can be controlled or modified by the user. The default values of the distances are such that there are no gaps between the cavities. 2. Angle of orientation of the individual cavity (flexible). The angle of orientation of the individual cavity is also listed in the layout design table which the user can change. For a multi-cavity layout, all the cavities have to be at the same angle of orientation as indicated in the layout design table. If the angle of orientation is modified, all the cavities will be rotated by the same angle of orientation without affecting the layout configuration. 3. Assembly mating relationship between each cavities (fixed). The orientation of the cavities with respect to each other is pre-defined for each individual layout configuration and is controlled by the assembly mating relationship between cavities. This is fixed for every layout configuration unless it is customised. Figure 12 shows an example of a single-cavity layout configuration and its geometrical parameters. The origin of the main insert/cavity is at the centre. The default values of X1 and Y1 are zero so that the cavity is at the centre of the layout (both origins overlap each other). The user can change the values of X1 and Y1, so that the cavity can be offset appropriately. Figure 13 shows an example of an eight-cavity layout configuration and its geometrical 8 parameters. The values of X and Y are the dimensions of the main insert/cavity. By default, the values of X1 and X2 are equal to X, the value of Y1 is equal to Y, and thus there is no gap between the cavities. The values of X1, X2, and Y1 can be increased to take into account the gaps between the cavities in the design. These values are listed in the layout design table. If one of the cavities has to be oriented by 90, the rest of the cavities will be rotated by the same angle, but the layout design remains the same. The user is able to rotate the cavities by changing the parameter in the layout design table. The resultant layout is shown in Fig. 14. 9 A complex cavity layout configuration, which has more geometrical parameters, must make use of equation to relate the parameters. 4. System Implementation A prototype of the parametric-controlled cavity layout design system for a plastic injection mould has been implemented using a Pentium III PC-compatible as the hardware. This prototype system uses a commercial CAD system (SolidWorks 2001) and a commercial database system (Microsoft as the software. The prototype system is developed using the Microsoft Visual C+ V6.0 programming language and the SolidWorks API (Application Programming Interface) in a SolidWorks is chosen primarily for two reasons: 1. The increasing trend in the CAD/CAM industry is to move towards the use of Windows-based PCs instead of UNIX workstations mainly because of the cost involved in purchasing the hardware. 2. The 3D CAD software is fully Windows-compatible, thus it is capable of integrating information from Microsoft Excel files into the CAD files (part, assembly, and drawing) smoothly 17. This prototype system has a configuration database of eight standard layout configurations that are listed in an Excel file. This is shown in Fig. 15(a). Corresponding to this configuration database, the layout design level, which is an assembly file in SolidWorks (layout.sldasm), has the same set of layout configurations. The configuration name in the Excel file corresponds to the name of the configurations in the layout assembly file, which is shown in Fig. 15(b). Every cavity layout assembly file (layout.sldasm) for each project will be pre-loaded with these layout configurations. When a required layout configuration is requested via the user interface, the layout configuration will be loaded. The user interface shown in Fig. 16 is prior to the loading of the requested layout configuration. Upon loading the requested layout configuration, the current layout configuration information will be listed in the list box. The user is then able to change the current layout configuration to any other available layout configurations that are found in the configuration database. This is illustrated in Fig. 17. The layout design table for the current layout configuration that contains the geometrical parameters can be activated when the user triggers the push button at the bottom of the user interface. When the values of the geometrical parameters are changed, the cavity layout design will be updated accordingly. Figure 18 shows the activation of the layout design table of the current layout configuration. 5. A Case Study A CAD model of a hand phone cover, shown in Fig. 19, is used in the following case study. Prior to the cavity layout design stage, the original CAD model has to be scaled according to the shrinkage value of the moulding resin to be used. The main insert is then created to encapsulate the shrunk part. This entire subassembly is known as the main insert subassembly (xxx cavity. sldasm), where “xxx” is the project name. Figure 20 shows the main insert subassembly. After the main insert subassembly is created, the cavity layout design system can be used to prepare the cavity layout of the mould assembly. 10 5.1 Scenario 1: Initial Cavity Layout Design In a mould design, the number of cavities to be built in a mould is always suggested by the customers, as they have to balance the investment in the tooling against the part cost. Initially, the customers had requested a two-cavity mould to be designed for this hand phone cover. After the creation of the main insert subassembly, the mould designer loads a layout configuration that is of a linear type which has two cavities using this cavity layout design system. The corresponding configuration name is L02 and is listed in the user interface as shown in Fig. 21. 5.2 Scenario 2: Modification in the Cavity Layout Design Technical discussion sessions between the customers and mould designers are common. This enables changes to be made to the 3D CAD files of both the product and mould as soon as possible, prior to mould manufacture. Changes are almost always inevitable and mould designers are never given any extension in the lead time. In this case, during a technical discussion session, the customers changed their minds and needed a linear four-cavity mould instead of a two-cavity mould so that the production rate of the hand phone covers can be increased. The mould designer can use the cavity layout design system to modify the existing cavity layout design to a linear four-cavity mould. The required new layout configuration can be selected from the available layout configurations that are listed in the configuration database. This is shown in Fig. 22. 11 5.3 Scenario 3: Gap is Required Between Cavities Finally, in another technical discussion session, the mould designer is required to introduce a gap of 20 mm between the cavities in the longitudinal direction, as shown in Fig. 23. In the cavity layout subassembly level, the mould designer uses the cavity layout system to activate the layout design table of the current layout configuration. The value of Y1 is changed from 50 mm to 70 mm to introduce a gap of 20 mm between the cavities in the longitudinal direction. Figure 24 shows the change of the value of Y1 in the layout design table. The result of the final design, after addition of the gap, is shown in Fig. 25. 12 6. Conclusions In this paper, an approach using a standardisation template is proposed for the development of a parametric-controlled cavity layout design system. Since this approach makes use of standardisation, it can be further applied to other components for mould assembly design if their design processes are repeatable or they have features that are commonly used for every mould design. The advantages of the developed cavity layout system are as follows: 1. The developed system has user-friendly interfaces. 2. Since it makes use of databases, it is highly flexible, and mould-making industries that have their own standards can customise the databases to suit their needs. 3. Because a pre-defined standardisation template is available in the layout design level of the mould assembly design, the required layout configuration can be loaded very quickly into the mould assembly design without the need to redesign the layout. 4. This system enables product designers and mould designers to have more useful technical discussions prior to mould manufacture as changes to the layout can be made immediately during the discussions. 5. This system saves time in the mould design process because it removes redundant work. This is very important for the mould-making industries since the lead time for mould making is decreasing. The developed system has some limitations. Although the databases and layout design tables can be customised, customization will be more difficult for more complex non-standard configurations because the correct geometrical parameters have to be determined. We are currently 13 working on applying a standardisation template for other components in mould design. References 1. K. S. Lee, J. Y. H, Fuh, Y. F. Zhang, A. Y. C. Nee and Z. Li, “ IMOLD: an intelligent plastic injection mold design and assembly system”, Proceedings of the 4th International Conference On Die and Mould Technology, pp. 3037, Malaysia, 46 June 1997. 2. K. S. Lee, Z. Li, J. Y. H, Fuh, Y. F. Zhang and A. Y. C. 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Ye, “Feature and associativity-based computer-aided design for plastic injection moulds”, PhD thesis, National University of Singapore, 2000. 14. X. G. Ye, J. Y. H. Fuh and K. S. Lee, “Automated assembly modeling for plastic injection moulds”, International Journal of Advanced Manufacturing Technology, 16, pp. 739747, 2000. 15. G. Menges, How to Make Injection Molds, Chapter 4, Hanser, Munich, 1986. 16. Joseph B. Dym, Injection Molds and Molding: A Practical Manual, Chapter 7, Van Nostrand Reinhold, New York, 1989. 17. SolidWorks 2001 Training Manual, “SolidWorks Essentials parts assemblies and drawings”, SolidWorks Corporation, Concord, Massachusetts 01742, 2001. 14 二、翻译文章 注塑模的参数控制型腔布局设计系统 M. L. H. Low and K. S. Lee 机械工程系，新加坡大学，新加坡 如今，塑料产品的上市时间变的越来越短，因此，制造注塑模的可用交货时间也变的少了。在模具的设计阶段有个省时的潜在方法，因为由于每个模具 设计可以是标准化的，所以一个设计程序可以被重复使用。本文提出了一种通过使用标准模版来控制几何参数的方法来设计注塑模的型腔布局。标准模版的型腔布局设计包括可能布局的配置。每个布局设计的配置都有其特有的由所有几何参数构成的布局设计表格。这个标准模版是预定义在合型设计的布局设计的级别时的。这样就能够确保要求的配置能够被快速地输入到模具装配设计中，而不需要重新设计布局。这使得它在模具制造前产品设计师和模具设计师之间的技术讨论上更有用。在讨论时直接改变 3D 型腔的布局设计，这样可以节省时间和避免错误传达。型腔设计的标准 模版便于各个模具制造公司依照顾客具体要求而制造他们各自的规格。 关键词：型腔布局设计；几何参数；合型；注塑模设计；标准模板 1简介 注塑法是在一个较好的公差范围内生产大量塑料零件的最简单的方法。在注塑法中有两个主要的要求。那就是注塑设备和注塑模。注塑制模机上有安装好的模具并且提供有将熔融的塑料从机器中转移到模具中的机械设，利用压力应用程序来加紧模具来喷出成型的塑料部件。注塑模是将熔融的塑料转变成最终具有详细尺寸形状的塑料部件的工具。如今，随着塑料部件的上市时间变得越来越短，在一个更短的时间里生产注塑模变得 更加必要。 注塑模具的设计及其相关的领域有很多工作都是依靠电脑技术来完成的。知识库系统例如 IMOLD1.2， IKMOULD3， ESMOLD4，台湾 5的国家程康大学 6的知识库系统，德雷塞尔大学的知识库系统等都是注塑模具设计较发达的。如 HyperQ/Plastic7， CIMP8，FIT9系统等 ,通过使用知识库系统在挑选塑性材料方面有了发展。在注塑法 10-12的分离设计技术上也同样有所提高。 据观察尽管模具制造公司仍在使用 3D CAD 软件来进行模具设计，大量的时间都浪费在了仔细 检查每个项目的同一设计程序。在模具设计阶段如果重复的设计程序能够标准化进而避免了常规任务就能够更好的节省时间。在合型方面一个有条理的树形分层设计也同样是个重要因素 13,14。然而，在型腔的布局设计中有极少的工作是控制参数，这样，这片领域将是我们主要的焦点。尽管在设计型腔的布局时有很多的方法 15,16，模具设计师们更倾向于使用最常见的设计方法，这样就有必要在型腔布局设计层面上制定标准。 本文介绍了基于标准模板通过控制参数来设计注塑模的型腔布局设计的方法。首先，必须确定一个有条理的树形合型分层设计。其次 ，对标准配置和不标准配置之间不同型腔配置进行分类。在配置数据库中将标准配置列表，并且每个配置有其自己的布局设计表来控制它自身的几何参数。这个标准模板在模具合型设计的布局设计阶段进行先验。 图 1.前嵌入（型腔）和后嵌入（型芯） 15 2注塑模的型腔布局设计 注塑模是将熔融的塑料转变成最终具有详细尺寸形状的塑料部件的工具。这样，一个模具的最后部分要包含有推出机构。大多数的模具由两部分构成：动模板和定模板。在有些模具制造公司，动模板也被称为凹模，定模板也被称为凸模。 表一所示为动模板（凹模）和定模板（凸模） 。熔融的塑性材料被注射进型腔中。熔融的塑性材料固化后就形成了部件。表二所示为一个简单的两板式注塑模。 图 2 单型腔合型 2.1 单型腔和多型腔的区别 通常，熔融塑性材料所注入的空间被称为型腔。型腔的排列被称为型腔的布置。当模具包含有超过一个的型腔时被称为多型腔模具。图 3（ a）和图 2（ b）所示为一个单型腔模具和一个多型腔模具。 单型腔模具通常用来制造大的直方的部件例如打印机的外壳和电视机的外壳。对于较小的部件如手机外壳和齿轮，一般更经济的用多型腔模具来生产，这样每个模具周期能够生产更多的部件。顾客通常决定 型腔的数目，所以他们不得不平衡机器设备的费用和部件的费用。 2.2 多型腔的布局 同时能生产不同产品的多型腔模具称为一个系列模具。然而，它并不经常用来设计有不同型腔的模具，因为型腔不一定能同时在同一个温度下被熔融的塑性材料填充满。 另一方面，一个多型腔模具在整个的模具周期中生产相同的产品会用到平衡布局和不平衡布局。平衡布局是指型腔能够在相同的熔融条件下同时全部被填充满 15,16。当使用不平衡布局时可能会产生成型不完全的模具，但是可以通过修改分型面的浇流道（熔融塑性材料从浇口流到型腔的通道）的长度来克服。然 而这不是一个高效的方法，在可能的情况下避免使用。图 4 所示为由于使用不平衡布局而导致了成型不完全的情况。 平衡布局能更进一步的分为两类：线形和环形。平衡线形布局适用于 2、 4、 8、 16、 32等型腔，也就是说它遵循 n2 系列。平衡环形布局可以有 3、 4、 5、 6 或者更多的型腔，但是由于空间限制在平衡环形布局的型腔布置上有数量的限制。图 5 所示是讨论过的多型腔布局。 16 3.设计方法 本章概况地介绍注塑模的高级参数控制型腔布局设计系统的设计方法。模具设计的有效工作方法包括将大量的组件和 部件安排到设计树的最合适的层次上。图 6 所示为第一级的组件和部件在设计树的合型层。设计树的第二层向前直到第 N 层的合型层上的组件和部件将被组合。在这个系统中，重点是“型腔的布局设计”。 图 3（ a）单型腔模具。（ b）多型腔模具 图 4 不平衡布局而导致了成型不完全 3.1 标准化程序 在模具设计过程中为节约时间，有必要鉴别通常使用的设计方法的特点。每个模具设计中重复使用的设计步骤可以被标准化。从图 7 中可以看出在型腔布局设计的标准化程序中有两个部分是互相影响的：零部件装配的标准化和型腔布局配置的标准化。 17 图 5 多型腔布局 图 6 合型分层设计树 图 7 在标准化程序中的相互关系 3.1.1 零件装配标准化 在型腔布局配置标准化前，有必要识别在型腔布局中在大量型腔中重复使用的零部件。表 8 所示为一个详细的型腔布局设计的树形层次设计结构图。在树形层次设计结构图的第二层中主要的嵌入部件有大量在层次设计树中第三层以前的被直接装配的零部件。它们可以被看做是主要成分和次要成分。主要成分存在于每个模具设计中。次要成分取决于所生产的塑料部 件，所以它们可能出现也可能不出现在模具设计中。 18 图 8 详细型腔布局设计的树形层次设计结构图 结果，将这些零部件直接放到主要嵌入部件下，确保每个重复使用的主要嵌入（型腔）将延续层次设计树第三层以前的相同零部件的使用。这样，就没有必要重复设计在型腔布局中的每个型腔中的相同零部件了。 3.1.2 型腔布局的结构标准化 有必要学习和将型腔布局标准化分类为标准化和非标准化。图 9 所示为型腔布局结构的标准化程序。 图 9 型腔布局结构的标准化程序。 19 一个型腔布局设计，可以被理解为或者是多腔布局或者是单腔布局，但是 通常是顾客来决定这个。单型腔布局总是被认为有一个标准的配置。多型腔模具可以同时生产不同产品或者同时生产相同产品。一个模具同时生产不同产品被认为是同系列的模具，这是不常见的设计。这样，一个多型腔系列模具就有一个非标准配置。 多型腔模具生产相同产品可以包含要么平衡布局设计要么非平衡布局设计。非平衡布局设计很少使用，结果它被认为是有一个非标准配置。然而，一个平衡布局设计也可以包含有一个线性布局设计或者是一个环形布局设计。这个取决于顾客要求的型腔的数目。这个必须注意，然而，布局设计也有其他非标准型腔数目也被分类在非 标准配置中。 将这些布局设计分为标准化后，他们的详细信息就可以列入标准模板中。在合型设计和支持所有的标准配置的型腔布局设计阶段标准模板要进行先验。这样就能确保要求的配置能够很快的载入到合型设计中而不用再次设计布局。 3.2 标准化模板 从图 10 中可以看出在标准模板中有两部分：配置数据库和部件设计表。配置数据库包括有所有的标准布局配置，每个布局配置都有它自己的带有几何参数的布局设计表。由于模具制造工业有他们自己的标准，这样配置数据库可以根据顾客具体要求来运用到那些预先被认为是非标准化的设计中。 图 10 标 准模板 3.2.1 配置数据库 一个数据库可以用来包含了所有的不同标准配置的列表。在这个数据库中的配置的总数目相当于在模具设计装配的型腔布局设计阶段的可利用布局配置的数目。在数据库所列信息就是配置数目、类型、和型腔数。表 1 所示是数据库的一个例子。每个可利用的布局配置的一般类型和型腔的数目的名字是配置数目。当布局的特殊类型和型腔的数目被要求时，适当的布局配置将会被载入到型腔布局设计中。 3.2.2 布局设计表 配置数据库中所列的每个标准配置都有它自己的布局设计表。布局设计表包含有布局配置的几何参数并且每个配置都是 独立的。更多的复合布局配置将有更多的几何参数来控制型腔布局。 图 11（ a）和 11（ b）所示为装配相同四个型腔布局的有一个大腔和四个小腔的模板的背面。它一般更经济，与用机械设备在一大块的钢板上制造独立的更小的腔相比，用机械设 20 备在制造一个大的腔更加容易。用机械制造一个大的腔的优点有： 1. 在腔与腔之间可以节省更过的空间，这样更小块的钢板就可以被使用了。 2. 与加工多个小的腔相比加工一个大的腔的加工时间要更快。 3. 加工大腔比加工小腔能获得更高的精确度。 结果，在布局设计表中的几何参数的默认值将导致腔于腔之间将没有间隙。然而 ，为是系统更加灵活，几何参数的默认值在需要的地方可以修改以此来适应每个模具设计。 图 11 模板背面 3.3 几何参数 几何参数有三个变量： 1. 型腔之间的距离。布局设计表中所列出的型腔之间的距离可以由使用者来控制或修改。距离的默认值就是这些型腔间没有间隙的值。 2. 个别型腔的取向角。个别型腔的取向角也被列在了布局设计表中，这些数值用户可以修改。对于一个多型腔布局，所有的型腔都必须如布局设计表中所说有相同的取向角。如果取向角被修改，所有的型腔将会旋转相同的取向角而不受结构 配置的影响。 3. 型腔间的装配关系。型腔间的方向与先验每个独特的布局配置有关并且由型腔间的装配关系控制。 图 12 所示为一个单型腔布局配置和它的它的几何参数的例子。主要嵌入 /型腔的原点是在中心。 X1 和 Y1 的默认值是 0 所以型腔的布局时在中心的（双方起源重叠）。使用者可改变 X1 和 Y1 的值，所以型腔可以适当的偏移。 图 13 所示是一个八型腔布局配置和它的几何参数的例子。 X和 Y值是主要嵌入 /型腔的大小。默认 X1、 X2 的值等于 X， Y1 的值等于 Y，这样型腔间就没有间隙。考虑到设计中的型腔间的间隙 X1、 X2 和 Y1 的值可以增加。这 些数值在布局设计表中都有列出。 如果一个型腔的方向不得不调整 90，剩下的型腔也要旋转相同的角度，但是布局设 21 计的残余也是同样。使用者可以通过改变布局设计表的参数来旋转型腔。最终的布局如图14 所示。一个复杂的型腔布局配置有更多的几何参数，必须确保参数方程的联系。 图 12 单型腔布局配置和几何参数 图 13 没有型腔旋转的八型腔布局配置 和几何参数图 图 14 型腔旋转的八型腔布局配置和几何参数 4.系统实现 注塑模的标准参数控制型腔布局设计系统通过奔腾 III PC兼容机作为计算机硬件来执行。这个原型系统使用商业 CAD系统（ SolidWorks2001）和商业数据库系统（ Microsoft Excel）作为软件。成熟的原型系统在 Windows NT环境下使用 Microsoft Visual CV6.0编程语言和SolidWorks API（应用程序设计接口）。 SolidWorks被挑选出来的两个主要的原因是： 1. 在 CAD/CAM工业放心日益增长的趋势是向 Windows-based PCs的使用来代替了 UNIX工作站的使用，主要是因为包含购买计算机硬件的花费。 2. 三维 CAD软件是 Windows系统完全兼容的，这样它能够平稳地整合从 Microsoft Excel文件到 CAD文件（部分，装配，图纸）的信息 17。 这个原型设计有一个列在 Excel文件中的八个标准布局配置的配置数据库。这个由图 15（ a）所示。与这个配置数据库一致，布局设计阶段， SolidWorks中的一个装配文件有相同的布局配置。在 Excel文件中的配置名与图 15（ b）所示的在布局装配文件中的装配名相对应。 每个设计中的每个型腔布局装配文件将会被这些布局配置预装载。当要求的布局结构按要求通道到用户界面 ，布局配置将被载入。用户界面如图 16所示是在要求的布局配置载入之前的。在载入要求的布局配置之上，最近的布局配置信息将会被列入列表框中。 对在配置数据库中找到的任何其他可用的布局结构，用户就能够改变当前布局结构。这个由图 17举例说明。 最近的布局结构的布局设计表包含有当用户触发了在用户界面底部的按钮时就能够激活的几何参数。当几何参数值改变，型腔布局设计将因此更新。图 18所示是激活了最近的布 22 局结构的布局设计表。 图 15 原型系统的配置数据库和布局模板 图 16 要求的布局配置载入之前的用户界面 图 17 要求的布局配置载入之后的用户界面 图 18布局设计表的用户界面 5.案例研究 如图 19所示的手机外壳的 CAD模型，使用了如下的案例研究。 在型腔布局设计阶段之前，原 CAD模型必须根据使用的模具损耗值来修剪。主要的嵌入部分会制造的能够压缩进收缩的部分。这个整个的部件被认为是主要的嵌入部件 (xxx cavity.sldasm),。“ XXX”是项目名。图 20所示是主要的嵌入部件。在主要的嵌入部件创建后，型腔布局设计系统将会被用于准备合型的型腔布局。 5.1方案 1：最初的型腔布局设计 在一个模具设计中，建立 在一个模具中的型腔的数目通常是有顾客建议的，这样他们必须平衡工件方面的投资和零件的花费。最初，顾客要求用一个两个型腔的模具来设计这个手机外壳。在创建了主要的嵌入部件后，模具设计师载入了一个使用型腔布局设计系统有两个型腔的线性布局结构。对应的配置名是 L02如图 21所示列入了用户列表中。 5.2方案 2：型腔布局设计中的修改 顾客与模具设计者间的工艺讨论会议是很普遍的。这样在模具制造前就能够尽可能早的修改三维 CAD文件中的产品和模具。修改基本上是不可避免的，模具设计者也从不会在主要的时间上延期。 既然这样，在工艺 讨论会议中，顾客改变他们的想法，需要一个线性的四个型腔的模具来代替两个型腔的模具，所以手机外壳的价格就要增加。模具设计者可以使用型腔布局设计系统来修改目前的型腔布局设计为一个线性的四个型腔的模具。要求的新的布局结构可以从配置数据库所列的可利用的布局结构中挑选出来。如图 22所示。 23 图 19 手机的 CAD模型 图 20 主要嵌入包装的收缩部分 图 21 线性两型腔的配置 图 22 线性 四型腔布局配置（布局配置变化后） 5.3方