注塑模的參數(shù)控制型腔布局設(shè)計系統(tǒng)外文文獻翻譯、中英文翻譯、外文翻譯

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. Nee, “Knowledge-based injection mold design system”, CIRP International Conference and Exhibition on Design and Production of Dies and Moulds, pp. 4550, Turkey, 1921 June 1997. 3. C. K. Mok, K. S. Chin and John K. L. Ho, “An interactive knowledge-based CAD system for mould design in injection moulding processes”, International Journal of Advanced Manufacturing Technology, 17, pp. 2738, 2001. 4. Kwai-Sang Chin and T. N. Wong, “Knowledge-based evaluation for the conceptual design development of injection molding parts”, Engineering Application of Artificial Intelligence, 9(4), pp. 359376, 1996. 5. Rong-Shean Lee, Yuh-Min Chen and Chang-Zou Lee, “Development of a concurrent mold design system: a knowledge-based approach”, Computer Integrated Manufacturing Systems, 10(4), pp. 287307, 1997. 6. A. A. Tseng, J. D. Kaplan, O. B. Arinze and T. J. 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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、翻譯文章 注塑模的參數(shù)控制型腔布局設(shè)計系統(tǒng) M. L. H. Low and K. S. Lee 機械工程系，新加坡大學，新加坡 如今，塑料產(chǎn)品的上市時間變的越來越短，因此，制造注塑模的可用交貨時間也變的少了。在模具的設(shè)計階段有個省時的潛在方法，因為由于每個模具 設(shè)計可以是標準化的，所以一個設(shè)計程序可以被重復使用。本文提出了一種通過使用標準模版來控制幾何參數(shù)的方法來設(shè)計注塑模的型腔布局。標準模版的型腔布局設(shè)計包括可能布局的配置。每個布局設(shè)計的配置都有其特有的由所有幾何參數(shù)構(gòu)成的布局設(shè)計表格。這個標準模版是預定義在合型設(shè)計的布局設(shè)計的級別時的。這樣就能夠確保要求的配置能夠被快速地輸入到模具裝配設(shè)計中，而不需要重新設(shè)計布局。這使得它在模具制造前產(chǎn)品設(shè)計師和模具設(shè)計師之間的技術(shù)討論上更有用。在討論時直接改變 3D 型腔的布局設(shè)計，這樣可以節(jié)省時間和避免錯誤傳達。型腔設(shè)計的標準 模版便于各個模具制造公司依照顧客具體要求而制造他們各自的規(guī)格。 關(guān)鍵詞：型腔布局設(shè)計；幾何參數(shù)；合型；注塑模設(shè)計；標準模板 1簡介 注塑法是在一個較好的公差范圍內(nèi)生產(chǎn)大量塑料零件的最簡單的方法。在注塑法中有兩個主要的要求。那就是注塑設(shè)備和注塑模。注塑制模機上有安裝好的模具并且提供有將熔融的塑料從機器中轉(zhuǎn)移到模具中的機械設(shè)，利用壓力應(yīng)用程序來加緊模具來噴出成型的塑料部件。注塑模是將熔融的塑料轉(zhuǎn)變成最終具有詳細尺寸形狀的塑料部件的工具。如今，隨著塑料部件的上市時間變得越來越短，在一個更短的時間里生產(chǎn)注塑模變得 更加必要。 注塑模具的設(shè)計及其相關(guān)的領(lǐng)域有很多工作都是依靠電腦技術(shù)來完成的。知識庫系統(tǒng)例如 IMOLD1.2， IKMOULD3， ESMOLD4，臺灣 5的國家程康大學 6的知識庫系統(tǒng)，德雷塞爾大學的知識庫系統(tǒng)等都是注塑模具設(shè)計較發(fā)達的。如 HyperQ/Plastic7， CIMP8，F(xiàn)IT9系統(tǒng)等 ,通過使用知識庫系統(tǒng)在挑選塑性材料方面有了發(fā)展。在注塑法 10-12的分離設(shè)計技術(shù)上也同樣有所提高。 據(jù)觀察盡管模具制造公司仍在使用 3D CAD 軟件來進行模具設(shè)計，大量的時間都浪費在了仔細 檢查每個項目的同一設(shè)計程序。在模具設(shè)計階段如果重復的設(shè)計程序能夠標準化進而避免了常規(guī)任務(wù)就能夠更好的節(jié)省時間。在合型方面一個有條理的樹形分層設(shè)計也同樣是個重要因素 13,14。然而，在型腔的布局設(shè)計中有極少的工作是控制參數(shù)，這樣，這片領(lǐng)域?qū)⑹俏覀冎饕慕裹c。盡管在設(shè)計型腔的布局時有很多的方法 15,16，模具設(shè)計師們更傾向于使用最常見的設(shè)計方法，這樣就有必要在型腔布局設(shè)計層面上制定標準。 本文介紹了基于標準模板通過控制參數(shù)來設(shè)計注塑模的型腔布局設(shè)計的方法。首先，必須確定一個有條理的樹形合型分層設(shè)計。其次 ，對標準配置和不標準配置之間不同型腔配置進行分類。在配置數(shù)據(jù)庫中將標準配置列表，并且每個配置有其自己的布局設(shè)計表來控制它自身的幾何參數(shù)。這個標準模板在模具合型設(shè)計的布局設(shè)計階段進行先驗。 圖 1.前嵌入（型腔）和后嵌入（型芯） 15 2注塑模的型腔布局設(shè)計 注塑模是將熔融的塑料轉(zhuǎn)變成最終具有詳細尺寸形狀的塑料部件的工具。這樣，一個模具的最后部分要包含有推出機構(gòu)。大多數(shù)的模具由兩部分構(gòu)成：動模板和定模板。在有些模具制造公司，動模板也被稱為凹模，定模板也被稱為凸模。 表一所示為動模板（凹模）和定模板（凸模） 。熔融的塑性材料被注射進型腔中。熔融的塑性材料固化后就形成了部件。表二所示為一個簡單的兩板式注塑模。 圖 2 單型腔合型 2.1 單型腔和多型腔的區(qū)別 通常，熔融塑性材料所注入的空間被稱為型腔。型腔的排列被稱為型腔的布置。當模具包含有超過一個的型腔時被稱為多型腔模具。圖 3（ a）和圖 2（ b）所示為一個單型腔模具和一個多型腔模具。 單型腔模具通常用來制造大的直方的部件例如打印機的外殼和電視機的外殼。對于較小的部件如手機外殼和齒輪，一般更經(jīng)濟的用多型腔模具來生產(chǎn)，這樣每個模具周期能夠生產(chǎn)更多的部件。顧客通常決定 型腔的數(shù)目，所以他們不得不平衡機器設(shè)備的費用和部件的費用。 2.2 多型腔的布局 同時能生產(chǎn)不同產(chǎn)品的多型腔模具稱為一個系列模具。然而，它并不經(jīng)常用來設(shè)計有不同型腔的模具，因為型腔不一定能同時在同一個溫度下被熔融的塑性材料填充滿。 另一方面，一個多型腔模具在整個的模具周期中生產(chǎn)相同的產(chǎn)品會用到平衡布局和不平衡布局。平衡布局是指型腔能夠在相同的熔融條件下同時全部被填充滿 15,16。當使用不平衡布局時可能會產(chǎn)生成型不完全的模具，但是可以通過修改分型面的澆流道（熔融塑性材料從澆口流到型腔的通道）的長度來克服。然 而這不是一個高效的方法，在可能的情況下避免使用。圖 4 所示為由于使用不平衡布局而導致了成型不完全的情況。 平衡布局能更進一步的分為兩類：線形和環(huán)形。平衡線形布局適用于 2、 4、 8、 16、 32等型腔，也就是說它遵循 n2 系列。平衡環(huán)形布局可以有 3、 4、 5、 6 或者更多的型腔，但是由于空間限制在平衡環(huán)形布局的型腔布置上有數(shù)量的限制。圖 5 所示是討論過的多型腔布局。 16 3.設(shè)計方法 本章概況地介紹注塑模的高級參數(shù)控制型腔布局設(shè)計系統(tǒng)的設(shè)計方法。模具設(shè)計的有效工作方法包括將大量的組件和 部件安排到設(shè)計樹的最合適的層次上。圖 6 所示為第一級的組件和部件在設(shè)計樹的合型層。設(shè)計樹的第二層向前直到第 N 層的合型層上的組件和部件將被組合。在這個系統(tǒng)中，重點是“型腔的布局設(shè)計”。 圖 3（ a）單型腔模具。（ b）多型腔模具 圖 4 不平衡布局而導致了成型不完全 3.1 標準化程序 在模具設(shè)計過程中為節(jié)約時間，有必要鑒別通常使用的設(shè)計方法的特點。每個模具設(shè)計中重復使用的設(shè)計步驟可以被標準化。從圖 7 中可以看出在型腔布局設(shè)計的標準化程序中有兩個部分是互相影響的：零部件裝配的標準化和型腔布局配置的標準化。 17 圖 5 多型腔布局 圖 6 合型分層設(shè)計樹 圖 7 在標準化程序中的相互關(guān)系 3.1.1 零件裝配標準化 在型腔布局配置標準化前，有必要識別在型腔布局中在大量型腔中重復使用的零部件。表 8 所示為一個詳細的型腔布局設(shè)計的樹形層次設(shè)計結(jié)構(gòu)圖。在樹形層次設(shè)計結(jié)構(gòu)圖的第二層中主要的嵌入部件有大量在層次設(shè)計樹中第三層以前的被直接裝配的零部件。它們可以被看做是主要成分和次要成分。主要成分存在于每個模具設(shè)計中。次要成分取決于所生產(chǎn)的塑料部 件，所以它們可能出現(xiàn)也可能不出現(xiàn)在模具設(shè)計中。 18 圖 8 詳細型腔布局設(shè)計的樹形層次設(shè)計結(jié)構(gòu)圖 結(jié)果，將這些零部件直接放到主要嵌入部件下，確保每個重復使用的主要嵌入（型腔）將延續(xù)層次設(shè)計樹第三層以前的相同零部件的使用。這樣，就沒有必要重復設(shè)計在型腔布局中的每個型腔中的相同零部件了。 3.1.2 型腔布局的結(jié)構(gòu)標準化 有必要學習和將型腔布局標準化分類為標準化和非標準化。圖 9 所示為型腔布局結(jié)構(gòu)的標準化程序。 圖 9 型腔布局結(jié)構(gòu)的標準化程序。 19 一個型腔布局設(shè)計，可以被理解為或者是多腔布局或者是單腔布局，但是 通常是顧客來決定這個。單型腔布局總是被認為有一個標準的配置。多型腔模具可以同時生產(chǎn)不同產(chǎn)品或者同時生產(chǎn)相同產(chǎn)品。一個模具同時生產(chǎn)不同產(chǎn)品被認為是同系列的模具，這是不常見的設(shè)計。這樣，一個多型腔系列模具就有一個非標準配置。 多型腔模具生產(chǎn)相同產(chǎn)品可以包含要么平衡布局設(shè)計要么非平衡布局設(shè)計。非平衡布局設(shè)計很少使用，結(jié)果它被認為是有一個非標準配置。然而，一個平衡布局設(shè)計也可以包含有一個線性布局設(shè)計或者是一個環(huán)形布局設(shè)計。這個取決于顧客要求的型腔的數(shù)目。這個必須注意，然而，布局設(shè)計也有其他非標準型腔數(shù)目也被分類在非 標準配置中。 將這些布局設(shè)計分為標準化后，他們的詳細信息就可以列入標準模板中。在合型設(shè)計和支持所有的標準配置的型腔布局設(shè)計階段標準模板要進行先驗。這樣就能確保要求的配置能夠很快的載入到合型設(shè)計中而不用再次設(shè)計布局。 3.2 標準化模板 從圖 10 中可以看出在標準模板中有兩部分：配置數(shù)據(jù)庫和部件設(shè)計表。配置數(shù)據(jù)庫包括有所有的標準布局配置，每個布局配置都有它自己的帶有幾何參數(shù)的布局設(shè)計表。由于模具制造工業(yè)有他們自己的標準，這樣配置數(shù)據(jù)庫可以根據(jù)顧客具體要求來運用到那些預先被認為是非標準化的設(shè)計中。 圖 10 標 準模板 3.2.1 配置數(shù)據(jù)庫 一個數(shù)據(jù)庫可以用來包含了所有的不同標準配置的列表。在這個數(shù)據(jù)庫中的配置的總數(shù)目相當于在模具設(shè)計裝配的型腔布局設(shè)計階段的可利用布局配置的數(shù)目。在數(shù)據(jù)庫所列信息就是配置數(shù)目、類型、和型腔數(shù)。表 1 所示是數(shù)據(jù)庫的一個例子。每個可利用的布局配置的一般類型和型腔的數(shù)目的名字是配置數(shù)目。當布局的特殊類型和型腔的數(shù)目被要求時，適當?shù)牟季峙渲脤惠d入到型腔布局設(shè)計中。 3.2.2 布局設(shè)計表 配置數(shù)據(jù)庫中所列的每個標準配置都有它自己的布局設(shè)計表。布局設(shè)計表包含有布局配置的幾何參數(shù)并且每個配置都是 獨立的。更多的復合布局配置將有更多的幾何參數(shù)來控制型腔布局。 圖 11（ a）和 11（ b）所示為裝配相同四個型腔布局的有一個大腔和四個小腔的模板的背面。它一般更經(jīng)濟，與用機械設(shè)備在一大塊的鋼板上制造獨立的更小的腔相比，用機械設(shè) 20 備在制造一個大的腔更加容易。用機械制造一個大的腔的優(yōu)點有： 1. 在腔與腔之間可以節(jié)省更過的空間，這樣更小塊的鋼板就可以被使用了。 2. 與加工多個小的腔相比加工一個大的腔的加工時間要更快。 3. 加工大腔比加工小腔能獲得更高的精確度。 結(jié)果，在布局設(shè)計表中的幾何參數(shù)的默認值將導致腔于腔之間將沒有間隙。然而 ，為是系統(tǒng)更加靈活，幾何參數(shù)的默認值在需要的地方可以修改以此來適應(yīng)每個模具設(shè)計。 圖 11 模板背面 3.3 幾何參數(shù) 幾何參數(shù)有三個變量： 1. 型腔之間的距離。布局設(shè)計表中所列出的型腔之間的距離可以由使用者來控制或修改。距離的默認值就是這些型腔間沒有間隙的值。 2. 個別型腔的取向角。個別型腔的取向角也被列在了布局設(shè)計表中，這些數(shù)值用戶可以修改。對于一個多型腔布局，所有的型腔都必須如布局設(shè)計表中所說有相同的取向角。如果取向角被修改，所有的型腔將會旋轉(zhuǎn)相同的取向角而不受結(jié)構(gòu) 配置的影響。 3. 型腔間的裝配關(guān)系。型腔間的方向與先驗每個獨特的布局配置有關(guān)并且由型腔間的裝配關(guān)系控制。 圖 12 所示為一個單型腔布局配置和它的它的幾何參數(shù)的例子。主要嵌入 /型腔的原點是在中心。 X1 和 Y1 的默認值是 0 所以型腔的布局時在中心的（雙方起源重疊）。使用者可改變 X1 和 Y1 的值，所以型腔可以適當?shù)钠啤?圖 13 所示是一個八型腔布局配置和它的幾何參數(shù)的例子。 X和 Y值是主要嵌入 /型腔的大小。默認 X1、 X2 的值等于 X， Y1 的值等于 Y，這樣型腔間就沒有間隙。考慮到設(shè)計中的型腔間的間隙 X1、 X2 和 Y1 的值可以增加。這 些數(shù)值在布局設(shè)計表中都有列出。 如果一個型腔的方向不得不調(diào)整 90，剩下的型腔也要旋轉(zhuǎn)相同的角度，但是布局設(shè) 21 計的殘余也是同樣。使用者可以通過改變布局設(shè)計表的參數(shù)來旋轉(zhuǎn)型腔。最終的布局如圖14 所示。一個復雜的型腔布局配置有更多的幾何參數(shù)，必須確保參數(shù)方程的聯(lián)系。 圖 12 單型腔布局配置和幾何參數(shù) 圖 13 沒有型腔旋轉(zhuǎn)的八型腔布局配置 和幾何參數(shù)圖 圖 14 型腔旋轉(zhuǎn)的八型腔布局配置和幾何參數(shù) 4.系統(tǒng)實現(xiàn) 注塑模的標準參數(shù)控制型腔布局設(shè)計系統(tǒng)通過奔騰 III PC兼容機作為計算機硬件來執(zhí)行。這個原型系統(tǒng)使用商業(yè) CAD系統(tǒng)（ SolidWorks2001）和商業(yè)數(shù)據(jù)庫系統(tǒng)（ Microsoft Excel）作為軟件。成熟的原型系統(tǒng)在 Windows NT環(huán)境下使用 Microsoft Visual CV6.0編程語言和SolidWorks API（應(yīng)用程序設(shè)計接口）。 SolidWorks被挑選出來的兩個主要的原因是： 1. 在 CAD/CAM工業(yè)放心日益增長的趨勢是向 Windows-based PCs的使用來代替了 UNIX工作站的使用，主要是因為包含購買計算機硬件的花費。 2. 三維 CAD軟件是 Windows系統(tǒng)完全兼容的，這樣它能夠平穩(wěn)地整合從 Microsoft Excel文件到 CAD文件（部分，裝配，圖紙）的信息 17。 這個原型設(shè)計有一個列在 Excel文件中的八個標準布局配置的配置數(shù)據(jù)庫。這個由圖 15（ a）所示。與這個配置數(shù)據(jù)庫一致，布局設(shè)計階段， SolidWorks中的一個裝配文件有相同的布局配置。在 Excel文件中的配置名與圖 15（ b）所示的在布局裝配文件中的裝配名相對應(yīng)。 每個設(shè)計中的每個型腔布局裝配文件將會被這些布局配置預裝載。當要求的布局結(jié)構(gòu)按要求通道到用戶界面 ，布局配置將被載入。用戶界面如圖 16所示是在要求的布局配置載入之前的。在載入要求的布局配置之上，最近的布局配置信息將會被列入列表框中。 對在配置數(shù)據(jù)庫中找到的任何其他可用的布局結(jié)構(gòu)，用戶就能夠改變當前布局結(jié)構(gòu)。這個由圖 17舉例說明。 最近的布局結(jié)構(gòu)的布局設(shè)計表包含有當用戶觸發(fā)了在用戶界面底部的按鈕時就能夠激活的幾何參數(shù)。當幾何參數(shù)值改變，型腔布局設(shè)計將因此更新。圖 18所示是激活了最近的布 22 局結(jié)構(gòu)的布局設(shè)計表。 圖 15 原型系統(tǒng)的配置數(shù)據(jù)庫和布局模板 圖 16 要求的布局配置載入之前的用戶界面 圖 17 要求的布局配置載入之后的用戶界面 圖 18布局設(shè)計表的用戶界面 5.案例研究 如圖 19所示的手機外殼的 CAD模型，使用了如下的案例研究。 在型腔布局設(shè)計階段之前，原 CAD模型必須根據(jù)使用的模具損耗值來修剪。主要的嵌入部分會制造的能夠壓縮進收縮的部分。這個整個的部件被認為是主要的嵌入部件 (xxx cavity.sldasm),?！?XXX”是項目名。圖 20所示是主要的嵌入部件。在主要的嵌入部件創(chuàng)建后，型腔布局設(shè)計系統(tǒng)將會被用于準備合型的型腔布局。 5.1方案 1：最初的型腔布局設(shè)計 在一個模具設(shè)計中，建立 在一個模具中的型腔的數(shù)目通常是有顧客建議的，這樣他們必須平衡工件方面的投資和零件的花費。最初，顧客要求用一個兩個型腔的模具來設(shè)計這個手機外殼。在創(chuàng)建了主要的嵌入部件后，模具設(shè)計師載入了一個使用型腔布局設(shè)計系統(tǒng)有兩個型腔的線性布局結(jié)構(gòu)。對應(yīng)的配置名是 L02如圖 21所示列入了用戶列表中。 5.2方案 2：型腔布局設(shè)計中的修改 顧客與模具設(shè)計者間的工藝討論會議是很普遍的。這樣在模具制造前就能夠盡可能早的修改三維 CAD文件中的產(chǎn)品和模具。修改基本上是不可避免的，模具設(shè)計者也從不會在主要的時間上延期。 既然這樣，在工藝 討論會議中，顧客改變他們的想法，需要一個線性的四個型腔的模具來代替兩個型腔的模具，所以手機外殼的價格就要增加。模具設(shè)計者可以使用型腔布局設(shè)計系統(tǒng)來修改目前的型腔布局設(shè)計為一個線性的四個型腔的模具。要求的新的布局結(jié)構(gòu)可以從配置數(shù)據(jù)庫所列的可利用的布局結(jié)構(gòu)中挑選出來。如圖 22所示。 23 圖 19 手機的 CAD模型 圖 20 主要嵌入包裝的收縮部分 圖 21 線性兩型腔的配置 圖 22 線性 四型腔布局配置（布局配置變化后） 5.3方