壓縮包內(nèi)含有CAD圖紙和說明書,均可直接下載獲得文件,所見所得,電腦查看更方便。Q 197216396 或 11970985
任 務 書
院(系): 專業(yè):
班 級: 學生: 學號:
一、畢業(yè)論文課題電視遙控器鍵盤蓋的注塑模設計
二、畢業(yè)論文工作自 20xx 年 3 月 12 日起至 20xx 年 6 月 15 日止
三、畢業(yè)論文進行地點
四、畢業(yè)論文的內(nèi)容要求
(一) 設計之原始數(shù)據(jù):
原始資料:電視遙控器鍵盤蓋實物一個
(二) 設計計算及說明部分內(nèi)容:
1.計算內(nèi)容與方案確定:
(1)成形零件設計:動、定模型腔尺寸的計算和布置。
(2)注塑機的選擇
(3)結(jié)構(gòu)系統(tǒng)設計計算:頂出機構(gòu)、抽芯機構(gòu)、冷卻、澆注、排氣系統(tǒng)等尺寸的計算與布置。
(4)強度設計和結(jié)構(gòu)草圖設計:各部件的強度校核。
2. 設計內(nèi)容:
(1)Pro/E環(huán)境下進行產(chǎn)品的模具設計;
(2)注射模裝配圖一張以上(0#計算機圖);
(3)各組成零件的零件圖(1#或2#計算機圖);
(4)編寫設計(論文)說明書(不少于2.0萬字,全部用計算機輸出);
(5)綜述文獻(要求書寫一篇6000~8000字的與畢業(yè)設計內(nèi)容相關的綜述文章)
(三) 主要參考資料:
1、《塑料注射模具設計實用手冊》,航空工業(yè)出版社。
2、模具實用技術(shù)叢書編委會《塑料模具設計制造與應用實例》,機械工業(yè)出版社 2002.7
3、伍先明確、王群等,《塑料模具設計指》導,國防工業(yè)出版社。2006.5
4、鄒繼強,《塑料模具設計參考資料匯編》 清華大學出版社2005.9
5、模具實用技術(shù)叢書編委會《模具材料與使用壽命》,機械工業(yè)出版社 2000.4
6、《材料力學》,高等教育出版社。
7、顏智偉,《塑料模具設計與機構(gòu)設計》,國防工業(yè)出版社,2005.8
8、《塑料模具設計手冊》編寫組, 《塑料模具設計手冊》
9、阮鋒等,Pro/ENGINEER2001模具設計與制造實用教程,機械工業(yè)出版社。
10、《Pro/ENGINEER Wildfire模具設計實例教程精解》,機械工業(yè)出版社。
11、《實戰(zhàn)Pro/ENGINEER2001模具設計》,中國鐵道出版社。
12、何滿才 《模具設計與加工MasterCAM9.0實例詳解》,人民郵電出版社。2006.0
(四)附屬專題
1、專題外文翻譯
檢索與閱讀與設計題目相關的外文資料,并書面翻譯(并不少于3000字)的外文資料。
指導教師
接受論文任務開始執(zhí)行日期 20xx 年 3 月 12 日
學生簽名
附件 英文文獻翻譯
譯文: 注射成型CAD/CAE/CAM集成系統(tǒng)
中國,華中科技大學,袁中雙, 李德群,陳興,葉翔高,高先科和肖景容著
本文描述的是一個CAD/CAE/CAM集成系統(tǒng)。在 CAD/CAE階段,注塑件的圖紙可與模具零件交互轉(zhuǎn)換,同時,根據(jù)用戶需求,可以進行機械檢驗、運行平衡分析、流動分析及冷卻模擬。在CAM階段,能夠生成線切割或銑床刀具路徑的數(shù)控磁帶。實踐表明:該系統(tǒng)是模具設計與制造的有用工具。
注射成型是當今工業(yè)最重要的聚合物加工方法之一,在復雜零件的大批量生產(chǎn)中,它具有以低成本獲得高精度的優(yōu)點。在相當長的一段時間里,經(jīng)驗、直覺與反復試驗已成為模具設計、制造及成型操作的關鍵因素。而這些方法已越來越低效且其成本也越來越高,尤其是當其應用于大型零件和高精度零件或新型聚合物的注射成型加工。而現(xiàn)在,大部分這些問題已通過結(jié)合CAD/CAE/CAM的最新技術(shù)進展成功的解決了。
近年來越來越多注射成型中的CAD/CAE/CAM集成系統(tǒng)已被研發(fā)并被傳遞到了西方工業(yè)國家,如美國AC一Teeh公司的C一M3.1,德國IKV公司開發(fā)的模具計算機輔助設計軟件,加拿大McCill大學的MCKAM和澳大利亞MoldFlow公司開發(fā)的二維流動軟件。通過使用這些軟件包,注射成型零件的生產(chǎn)力及其數(shù)量能夠提高,同時也縮短了其啟動時間。
自1980以來中國的注射成型CAD/CAE/CAM技術(shù)已取得了飛速發(fā)展. 我國作為這一領域的先驅(qū),已經(jīng)學習和開發(fā)注射成型CAD/CAE/CAM技術(shù)多年。 通過五年的發(fā)展和實踐證明,一個注射成型CAD/CAE/CAM集成系統(tǒng)HSC-1.1,已被開發(fā)并且成功的被許多工廠所采用。
系統(tǒng)描述
HSC- 1.1是建立在個人電腦如PC386和PC486上的。其理想的內(nèi)存大于等于4 MB,而其外部存儲容量超過100 MB。
圖1所示為HSC - 1.1的軟件要求。該系統(tǒng)是在操作系統(tǒng)II(OS/ 2)或MS - DOS環(huán)境下開發(fā)和運行的。在該系統(tǒng)中AutoCAD 10.0只作為一個圖形編輯和繪圖軟件。編程采用的是標準Fortran語言和AutoLISP 77。除了幾個圖形驅(qū)動程序外,計算機中所有系統(tǒng)的軟件是獨立的,以確保該系統(tǒng)有較好的可移植性.
如圖2所示。HSC- 1.1集成了9個基于用戶需求的設計功能模塊。系統(tǒng)中的所有模塊都是由一個名為’控制面板'或'控制菜單'的主控程序監(jiān)控。用戶可以通過控制面板命令顯示在屏幕上的菜單來調(diào)用任何模塊。而數(shù)據(jù)以數(shù)據(jù)文件的形式自動的從一個模塊交換到另一個模塊中。圖3所示為HSC - 1.1數(shù)據(jù)流程圖。
HSC-1.1軟件要求
圖2 HSC-1.1功能模塊
HSC-1.1數(shù)據(jù)流動表
CAD功能模塊
CAD模塊的任務是高效的把注射成型零件的圖紙轉(zhuǎn)換成模具零件圖紙,并為模擬和數(shù)控模塊提供所需數(shù)據(jù)。由于復雜型腔,一個曲面造型程序已包絡在圖形輸入中了。故平面,曲面和雙三次曲面可以輕松地創(chuàng)建。曲面的點坐標可由零件圖尺寸和先前輸入點坐標的程序來計算。當零件圖紙的表面一個又一個的創(chuàng)建時,零件的尺寸通過互動尺寸將轉(zhuǎn)換成型腔和型芯,而型腔和型芯的數(shù)據(jù)都將被記錄下來作為為模具設計和模擬用。
一種由中國人民共和國機電部發(fā)出的包含10種模具標準件套的據(jù)庫已經(jīng)設立了。每一套模具類包含13系列。因此,有31150套模具組合完全在數(shù)據(jù)庫中。一旦腔布局確定,所有的標準模具零件可以通過互動尺寸自動選擇。
該系統(tǒng)為用戶設計熱流道系統(tǒng),編輯型腔和型芯結(jié)構(gòu),布置頂針腳和冷卻水道提供了一個功能組。最后能夠生成所有的模具零件圖,包括動模裝配圖,定模裝配圖和模具總裝配圖。圖4所示為上海第九無線電廠生產(chǎn)的彩電開關插座的模具裝配圖。
模具總裝圖
CAE功能模塊
CAE模塊包括CAD與CAE模塊間的界面,模板的機械檢驗,運動平衡分析,流動和冷卻仿真。在這些CAE模塊的幫助下,模具結(jié)構(gòu)設計得到了改善,同時我們能在模具制造前解決注射成型零件在注射過程中可能出現(xiàn)的缺陷,如降解、注射量不足、熔接痕位置不當。
通過CAD與CAE模塊間的界面讀取型腔的幾何模型及在CAD前一階段制成的可自動生成有限元網(wǎng)格模型的送料系統(tǒng)。用戶使用該界面,還可以選擇聚合物,冷卻液,模具材料和設置如注射溫度,注射時間,冷卻液溫度等成型工藝條件。該界面從數(shù)據(jù)庫中讀取材料的屬性數(shù)據(jù),并將網(wǎng)格結(jié)構(gòu)、材料性能及成型工藝條件寫入作為如下介紹CAE模塊輸入的數(shù)據(jù)文件中。
目前,該系統(tǒng)使用二維有限元法(FEM)來分析模板的強度及其一個典型的模具截面的剛度。而基于三維有限元法的分析程序也正在開發(fā)中。
為了保證在一模多腔生產(chǎn)中獲得同等質(zhì)量的注射成型零件,每個型腔應在相同的壓力和溫度下同時填充。這就要求澆注系統(tǒng)是平衡的。在HSC - 1.1中其平衡能夠通過調(diào)整流道尺寸和用戶初步設計階段設計的最不可能平衡的澆口的尺寸來獲得。
流體模擬程序是該系統(tǒng)中最基本且最有用的分析之一。型腔流體控制方程能夠通過將經(jīng)典赫爾蕭流擴展至非彈性流體中來獲得。非牛頓流體在非等溫條件下:
其中P,T表示熔體壓力和溫度,和分別代表熔體的粘度和剪切速率;‘ - '表示了Z的平均偏導數(shù)p,和 K,分別表示熔體的密度、比熱和導電率;同時b表示的是半板厚度。
因為注射成型零件的厚度尺寸通常比其模具A、B板的厚度小的多,故在解決此問題時,我們采用了一種強大的數(shù)值方案,即采用有限元與有限差分混合法。在該方案的實施過程中,平面統(tǒng)籌以有限元法來描述,同時,塑件壁厚方向的變量分布和時間導數(shù)是以有限差分來表達的。我們采用體積控制法推導出了有限元法及跟蹤了熔體前端的流動。通過使用該流動仿真,用戶能夠獲取如壓力、流速、溫度分布、總壓降及夾緊力等對送料系統(tǒng)設計和優(yōu)化工藝條件很有幫助的信息;此外,用戶還能夠通過改變澆口的數(shù)量和位置來促進型腔的填充并獲得最佳的流態(tài)。
冷卻模擬包括三維穩(wěn)態(tài)和瞬態(tài)冷卻分析。三維穩(wěn)態(tài)冷卻分析采用的是邊界元法(BEM)。型腔表面建模,冷卻線和外部表面公式已經(jīng)建立并證明是可靠和有效的。基于穩(wěn)態(tài)冷卻仿真,三維瞬態(tài)冷卻仿真已經(jīng)研制成功。一種新的邊界元法已通過此模塊,以消除數(shù)值機構(gòu)一體化。有了這個組件,用戶可以計算腔與道之間的換熱,減少了冷卻時間并降低了模具與注塑成型零件表面的預熱溫度。
CAE模塊的所有執(zhí)行結(jié)果可以以等高線圖,陰影彩色圖像和各種曲線圖動態(tài)顯示,以幫助用戶提高他們的設計效率。
CAM功能模塊
刀具路徑的創(chuàng)建基于前述CAD階段繪制的型腔和型芯的幾何模型。對于數(shù)控線切割機床和數(shù)控銑床,其刀具路徑的數(shù)控磁盤是通過使用后置處理來生成的。目前,僅有數(shù)控線切割的功能在實踐中有采用。而我國工廠通過使用HSC-1.1系統(tǒng)已設計和制造了許多注射模具。
結(jié)論
HSC-1.1是一個集成CAD/CAE/CAM的注射成型系統(tǒng)。除少數(shù)圖形驅(qū)動器程序外,計算機系統(tǒng)的其他所有程序是獨立的。這就確保了系統(tǒng)良好的可移植性。同時,系統(tǒng)模塊化結(jié)構(gòu),也保證了系統(tǒng)中每一個模塊具有良好的延展性及維修性。實踐表明:HSC-1.1是一個強大的模具設計和制造工具,它可以幫助工程師以較低的模具成本獲得較好的模具質(zhì)量。因此,HSC-1.1在模具行業(yè)中的運用已越來越廣泛了。
參考文獻:
1 . WANG, K. K. : Polymer Plastics Technology Engineering, 1980, 1, p.75
2 .MENGES, G.: Plastics Engineering,1983, 8, p.37
3 .KAMAL, M. R. etal.: Application of computer aided engineering in injection moulding' (Hanser Publisher, 1987,p.247)
4 .AUSTIN, C: ' Application of computer aided engineering in injection moulding(Hanser Publisher, 1987, p. 137)
5 .WANG, V. W., Ph.D. thesis, Cornell University, 1985
原文: Integrated CAD/CAE/CAM system for injection moulding
by Yuan Zhongshuang, Li Dequn, Chen Xing, Ye Xiangao,Gao Xianke and Xiao Jingrong
Huazhong University of Science & Technology, China
An integrated CAD/CAE/CAM system, HSC-1.1, is described in this article. At the CAD/CAE stage the drawings of injection moulded parts can be transformed into the drawings of the mould parts interactively and, according to the user's needs, the mechanical check, runner balance analysis, flow simulation and cooling simulation can be carried out. NC tapes for wire cutting or milling machine tools can be generated at the CAM stage. The practice shows that the system is a useful tool for mould designers and manufacturers.
Introduction
Injection moulding is one of the most important polymer processing operations in industry today. It is superior for mass production of complex parts to high precision at low cost. For a long time, experience, intuition and trial and error have been key factors in mould designing, mould manufacturing and moulding operation. These approaches have become increasingly inefficient and costly, especially when applied to the moulding of large parts and parts of high precision or to the processing of new kinds of polymers. Now some of these problems are being solved successfully by combining recent advances in CAD, CAE and CAM technology.
In recent years more and more CAD/CAE/CAM systems for injection moulding have been developed and delivered in Western industrialized countries, such as C-MOULD 3.1 of AC Technology Inc. in the USA, CAD-MOULD of IKV in Germany, McKAM-ll of McCill University in Canada, and MoldFlow in Australia. With the help of these software packages the productivity and quality of injection moulded parts can be improved and the start-up time can be shortened.
CAD/CAE/CAM technology for injection moulding has been developed quickly in China since
1980. As a pioneer in this field in our country, we have studied and developed CAD/CAE/CAM technology of injection moulding for many years. Through five years' development and practical verification, an integrated CAD/CAE/CAM system for injection moulding, HSC-1.1, has been developed and put into use successfully in many factories.
System description
HSC-1.1 is developed on personal computers such as the PC386 and PC486. The desirable internal storage is 4 MB or more, and the external storage is more than 100 MB.
Fig. 1 shows the software requirements of HSC-1.1. The system is developed and run under the
environment of Operating System II (OS/2) or MS-DOS. In the system AutoCAD-10.0 is used only as a graphic editor and drawing software. Standard Fortran 77 and AutoLisp are used for programming. Except for a few of programs for graphic driver, all the software in the system is independent of computers, which ensures good portability of the system..
As shown in Fig. 2, HSC-1.1 integrates nine modules with their function design based on the requirements of users. All modules in the system are supervised by a main control program named control panel' or 'control menu'. Users can invoke any module by ordering the menu displayed on the screen by the control panel. The data exchange from one module to another is implemented automatically in the form of data files. Fig. 3 shows the data flowchart of HSC-1.1.
Function of CAD modules
The task of CAD modules is to transform the drawings of injection moulded parts into the drawings of mould parts efficiently and provide necessary data for simulation and NC modules. Due to complex cavities, a surface modelling program has been eveloped for graphic input. Planes, regular surfaces and bi-cubic surfaces can be created easily. The co-ordinates of points on surfaces
can be calculated by the programusing dimensions of the part drawing and the co-ordinates of the points input before. While the part drawing is being input one surface after another, the dimensions of the part will be transformed into the dimensions of the cavity and core through interaction. The data for the cavity and core are recorded for both mould design and simulation.
A database for standard mould sets has been set up which contains ten kinds of standard mould sets issued by the Electrical Ministry of the People's Republic of China. Each kind of mould set contains 13 series. Hence there are 31150 combinations of mould sets altogether in the database. Once the cavity layout is determined, all the standard mould parts can be selected automatically and dimensioned through interaction.
The system provides a group of functions for users to design the runner system, edit construction of cavity and core and arrange ejection pins and cooling lines. Finally all the mould part drawings including moving mould assembly, stationary mould assembly and general mould assembly drawing can be produced. Fig. 4 shows a mould assembly drawing of a switch socket made in the Shanghai No. 9 Radio Factory for colour TV sets.
Function of CAE modules
CAE modules include the interface between CAD and CAE modules, mechanical check for mould plates, runner balance analysis, flow simulation and cooling simulation. With the help of these CAE modules the mould construction design can be improved and possible defects in injection moulded parts such as degradation, short shots, and improper location of weld lines can be addressed before mould making.
The interface between CAD and CAE modules reads the geometric model of cavity and delivery system which is produced at the previous CAD stage and generates FEM mesh automatically. Using the interface, users can also select polymer, coolant, mould material and set process conditions such as injection temperature, injection time, coolant temperature etc. The interface reads the property data of the materials from the data bank and writes the mesh configuration, material properties and process conditions into data files which are the inputs for the CAE modules described below.
Currently the system uses a 2D finite-element method (FEM) to analyse the mould plate's strength and rigidity for a typical mould cross-section. An analysis program based on a 3D FEM is under development.
In order to guarantee the same qualities of the injection moulded parts produced in multi-cavities, each cavity must be filled simultaneously at the same pressure and temperature. This requires the runner system to be balanced. In HSC-1.1 the balance can be reached by correcting the dimensions of runners and gates designed by users at the preliminary design stage which are most probably not balanced.
The flow simulation program is one of the most basic and useful analyses in the system. The
governing equations for flow in cavity can be obtained by extending the classical Hele-Shaw flow to an inelastic, non-Newtonian fluid under non-isothermal conditions:
i-(rti) + J- (bv) =0
dX df/
+u+ v
dt dx By
Bz2
where P, Fare the pressure and temperature of melt, respectively; r|, y represent viscosity and shear rate; '—' denotes an average over z, the gap wise co-ordinate; p, Cp and K are density, specific heat and heat conductivity of the melt, respectively; and b is the half gap thickness. Because the thickness dimension of an injection moulded part is often much smaller than the other two dimensions, a powerful numerical scheme, which is the hybrid of the finite element and finite difference methods (FEM/FDM), is adopted in the solution. In the implementation of the scheme, the planar co-ordinates are described in terms of finite elements and the gapwise and time derivatives are expressed in terms of finite differences. A control volume approach is adopted to derive the finite-element formulation and track the melt front movement. By use of flow simulation, users can acquire information such as pressure, velocity and temperature distributions, total pressure drop, clamp force etc., which is very helpful in designing the deliver helpful in designing the delivery system and optimising the process conditions. Users can also animate the filling of the cavity and obtain an optimum flow pattern by changing the number and locations of gates.
Cooling simulation includes 3D steady and transient cooling analyses. The 3D steady cooling analysis uses the boundary element method (BEM). Formulas for modelling the cavity surfaces, cooling lines and exterior surfaces have been established and proven to be reliable and effective. Based on the steady cooling simulation, 3D transient cooling simulation has been developed. A novel BEM has been adopted in this module to eliminate numerical body integration. With the help of this module users can calculate heat transfer between cavity and cooling channels, reduce cooling time and predict temperature along mould and injection moulded part surfaces.
All results of CAE modules can be displayed dynamically with contour plots, shaded colour images and various curve plots to aid users in improving their design.
Function of CAM module
The cutter location files can be created based on the geometry of cavity and core which is modelled at the previous CAD stage. NC tapes can then be generated by use of postprocessors for both NC wire cutting machine tools and NC milling machine tools. Currently only the function of NC wire cutting is used in practice. A lot of injection moulds have been designed and manufactured by using the system HSC-1.1 in factories in our country.
Conclusions
HSC-1.1 is an integrated CAD/CAE/CAM system for injection moulding. All programs in the system are independent of computers except a few programs for the graphic driver. It ensures the system's good portability. The modular structure of the system guarantees that each module of the system has good expandability and maintainability. The practice shows that HSC-1.1 is a powerful tool for mould designing and manufacturing. It can assist engineers in cutting mould cost and improving mould quality. HSC-1.1 will find more and more applications in the mould industry.
References
1 WANG, K. K. : Polymer Plastics Technology Engineering, 1980, 1, p.75
2 MENGES, G.: Plastics Engineering, 1983, 8, p.37
3 KAMAL, M. R. etal.: Application of computer aided engineering in injection moulding' (Hanser Publisher, 1987, p.247)
4 AUSTIN, C: 'Application of computer aided engineering in injection moulding (Hanser Publisher, 1987, p. 137)
5 WANG, V. W., Ph.D. thesis, Cornell University, 1985 ?IEE: 1993 The authors are with Huazhong University of Science & Technology, Wuhan 430074, People's Republic of China