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塑料模具CAD集成技术摘要：通过分析计算机辅助注射模设计和制造的各个环节中共享的技术和信息，本文揭示了注射模CAD的集成技术的根本内涵，并提出了它的研究热点和趋势。关键词： 计算机辅助；CAD；设计制造1.塑料模具CAD集成技术塑料模具的制造，包括塑料产品的造型设计、模具的结构设计及分析、模具的数控加工(铣削、电加工、线切割等)、抛光和配试模以及快速成形制造等。各个环节所涉及的CAD单元技术有:造型和结构设计(CAD)、产品外形的快速反求(RE)、结构分析与优化设计(CAE)、辅助制造(CAM)、加工过程虚拟仿真(SIMULATION)、产品及模具的快速成形(RP)、辅助工艺过程(CAPP)和产品数据管理技术(PDM)等。塑料模具CAD集成技术,就是把塑料模具制造过程所涉及的各项单元技术集成起来,统一数据库和文件传输格式,实现信息集成和数据资源共享,从而大大缩短模具的设计制造周期,提高制模质量。2.塑料产品的CAD设计与外形的快速反求进行塑料模具设计制造的第一步是塑件产品的设计。传统产品设计方法是设计者对产品的三维构思用二维平面图纸表达出来,图纸上标明工艺及施工方法,这种方法决定了所设计图形的简单性及不能直接控制制造质量。现代设计方法是设计者在电脑上直接建立产品的三维模型,根据产品三维模型进行模具结构设计及优化设计,再根据模具结构设计三维模型进行加工编程及编制工艺计划。这种方法使产品模型设计、模具结构设计、加工编程及工艺设计都以3D数据为基础, 实现数据共享,不仅能快速提高设计效率,而且能保证质量, 降低成本。电脑塑件产品模型的来源有三种: 利用CAD系统软件进行产品模型设计、利用实物测量进行快速反求建模、利用其它CAD系统的标准格式文件。针对这三种产品模型的来源方式,目前已研究出各种技术来提高产品模型的设计效率和质量。下面进一步分析各种技术的内涵和特点。利用CAD系统软件进行产品模型设计,其技术主要包括二维几何图形的绘制、二维参数化图形的设计、三维实体造型设计、三维特征造型设计、三维参数化实体造型设计、三维曲面造型设计、空间自由造型设计、产品的外观渲染、产品的动态广告设计等等。这些软件有许多典型的代表。二维软件有:ME10、CADKEY、AUTOCAD、DHCAD、Genis、Sigraph等；三维软件有:UGII、PRO/E、IDEAS、CATIA、EUCLID等;产品自由造型及广告设计的软件有:Alias、CDRS等。二维几何图形的绘制是利用平面CAD软件绘制零件图形,即用计算机代替手工绘图;而二维参数化,即计算机实现了图形的变量设计,使修改更加方便;三维造型设计是数字化的产品的真实形状设计,它完全表达了产品,能够进一步为模具设计、分析和加工提供必要的数学模型;空间自由造型设计是产品外形的艺术设计，使产品不仅是功能产品,也是艺术品;产品的外观渲染是产品的效果设计,使产品更加美观、颜色更加能迎合人们的各种需求;产品的动态广告设计是将产品设计的结果直接制作宣传广告,进行市场推广。利用实物测量进行快速反求建模是目前研究的热点之一,它是产品仿型基础上进行产品修改设计的重要技术。其基本原理是通过三座标测量机、激光测量机或电子抄数仪对实物进行扫描测量,把测量所获得的数字化的大量数据点送入高级CAD软件的反求模块或专用的反求软件中, 反求软件可直接读取点数据群, 并可对点数据群进行编辑、过滤、整理、求精、排序、局部修改与重组, 然后自动生成曲面, 最终获得同实物精确一致的或经改造的电脑塑件产品模型。这一方式可极大提高新产品设计速率。目前较成熟的曲面反求建模软件有:Surfacer, Cimatronrenge, Strim100等。利用其它CAD系统的标准格式文件来建模,这一方式较方便。由于市场的全球化和INTERNET网络技术的发展,模具企业的CAD技术交流和合作有许多通过CAD文件方式进行。由于CAD系统种类较多,因此文件的格式就必须遵循国际标准,如DXF、IGES、STEP、VDA、STL等。通过读取标准格式文件来直接建立或修改后建立产品模型，既可加快、加深用户与模具厂家的交流，也可缩短产品设计周期。3.模具的CAD设计与分析模具的CAD设计、分析,包括根据产品模型进行模具分型面的设计、确定型腔和型芯、模具结构的详细设计、塑料充填过程分析等几个方面。利用先进的特征造型软件如PRO/E、UGII等很容易地确定分型面,生成上下模腔和模芯,再进行流道、浇口以及冷却水管的布置等。确定了这些设计数据以后,再利用模具分析软件,如MOLDFLOW、CFLOW进行塑料的成形过程分析。根据MOLDFOLW软件和它的丰富的材料、工艺数据库,通过输入成形工艺参数,可动态仿真分析塑料在注塑模腔内的注射过程流动情况(含多浇口注射时的塑料汇流纹分析)、分析温度压力变化情况、分析注塑件残余应力等,根据分析情况来检查模具结构的合理性、流动状态的合理性、产品的质量问题等。比如是否存在浇注系统不合理,出现流道和浇口位置尺寸不当,无法平衡充满型腔;是否存在产品结构不合理或模具结构不合理,出现产品充不满(即短射现象);是否冷却不均匀,影响生产效率和产品质量;是否存在注塑工艺不对,出现产品的翘曲变形等。模具通过CAD设计和分析,就可以将错误消除在设计阶段,提高一次试模成功率。在塑料模具设计和分析这一阶段应用了许多新的电脑辅助技术,如参数化技术、特征造型技术、数据库技术等。塑料模具中有许多标准件, 如标准模架、顶出机构、浇注系统、冷却系统等都可以采用基于数据库管理的参数化特征造型设计方法进行设计或建立标准件库,这样既可以实现数据共享,又可以满足用户对设计的随时修改,使模具的设计分析快速、准确、高效。参数化特征造型不仅可以完整地描述产品的几何图形信息,而且可以获得产品的精度、材料及装配等信息,其所建立的产品模型是一种易于处理、能反映设计意图和加工特征的模型。因此,参数化特征造型技术是模具制造过程最重要的技术之一。4.模具的CAM技术的应用、加工仿真及制造模具的计算机辅助制造(CAM)技术主要应用在数控铣削加工、线切割加工、电火花加工等方面。CAM技术尤其是在复杂模具的型腔、型芯及电极的铣削加工中起着更加重要的作用。其主要的技术特点包括:(1)粗、精加工刀具轨迹的优化规划和NC指令的产生，(2)刀具种类、特性和材料库的建立，(3 切削加工工艺参数的确定，(4)普通切削和高速切削加工的特性控制，(5)过切检查与加工表面的精度控制，(6)加工过程的电脑实体仿真切削，(7)电脑控制数控机床的DNC技术及群控技术的应用等等。在CAM技术的应用中特别需要CAD三维产品模型数据。较多的专业电脑编程软件如MASTERCAM、UNIMOD、CIMATRON等在多曲面的编程加工时对产品的曲面模型有较高的要求,如相邻曲面的U、V方向的一致性、曲面与曲面的高精度拟合、曲面斜率连续变化等。在高级CAD/CAM一体化系统中(如UGII、PRO/E),由于利用了参数化特征造型设计和同一数据库技术，使得产品模型数据、模具的型腔和型芯模型数据、刀具轨迹数据有着内在的联系，产品模型的修改刀具轨迹亦自动修改。模具加工实体仿真技术越来越成熟, 也越来越受到人们的重视。加工实体仿真是在电脑上模仿机床的加工过程, 能直观反映加工的结果，能直接评估加工后零件的质量，能检查出加工的错误。在检查加工后零件的质量时，可在电脑上对加工后的实体模型进行任意的剖切,直接测量其尺寸和精度。因此，它能把错误消除在加工工艺编程设计阶段，减少加工后的修补和返工，大大提高模具的制造效率和质量。5.塑料产品及其模具的快速成形制造塑料产品及其模具用电脑CAD技术设计完成后，可通过快速成形技术来制造。这是一种全新概念的制造技术，它摒弃了传统的机械加工方法。其成形原理是将三维CAD实体模型离散成设定厚度的一系列片层数据，利用激光成形机或其它成形设备读取这些数据，用材料添加法技术，依次将每层堆积起来成形。这一技术称为快速自动成形技术(Rapid Prototype)。它也是CAD集成技术的重要组成部分。第一台快速成形设备于1987年在美国3D公司诞生，由于其特点是与制造的产品的复杂程度无关，给制造业带来巨大的震动。此后十年，快速成形技术得到飞速发展，设备的种类也层出不穷，从材料固化方法可分为激光和非激光烧结法(SLS)、固体表层造型法(SGC)、层片制造法(LOM)、熔化沉积法(FDM)、选区粘结法(DSPC)、激光气相沉积法(SALD)等。各种方法特点是:SLA法是最早应用的快速成形技术，初期市场占有较大的分额，但由于材料范围窄，成本较高，成形件耐热、耐负荷和着色能力低，近年逐渐被其它方法所代替。FDM法由于成形速度快，成本低，在塑料产品行业中得到较好的应用，由于零件的尺寸小，精度差，也受到一定的限制。LOM法由于采用纸或者是薄片塑料，成本低，且激光只照射每一层的轮廓边缘，因而成形速度快，但产品表面质量差。SLS法是用激光进行烧结，采用的材料较广，如塑料、蜡料、陶瓷、金属等均可成形，成形件耐热、耐负荷和着色能力较强，具有广泛的应用前景。其它方法也在某些特种加工中得到应用。根据上述成形法特点，快速成形技术的作用主要在于:制造用于设计和试验的产品模型、制造用于小批量生产的模具和小批量特殊零件的加工。快速成形技术制造的产品模型在材质方面比传统加工方法制造的产品模型有所差别，但在外形及尺寸方面几乎完全一样，而且有一定的机械强度，可作功能性试验，同时经过表面处理，看起来与真实产品一样，可作广告宣传品。快速成形技术制造的模具，目前主要是软材料的成形模(蜡模、环氧树脂模、硅橡胶模、低熔点合金铸造模等)和陶瓷或金属基合成材料硬型腔模。制造硬模时可用快速成形零件作母模先制作环氧树脂模或其它材料的软模, 在软模中浇注陶瓷或石膏模, 然后浇铸钢成钢模，或者在软模中浇注混合有化学粘结剂的钢粉，进行烧结成钢模。快速成形技术制造的钢模需进一步做抛光等后加工，制成小批量生产的注塑模。由于模具是用钢粉浇注或烧结而成，材质与普通模具钢有一定的差距，因此，寿命较短，只能做试制产品或小批量生产。另外，快速成形技术也可以制作特殊的零件，如用冶金粉末法制作金属电极、精密铸造法制作铜电极、研模法制作石墨电极等。快速成形技术制作模具和产品的成型设备，均是读取CAD系统产生的STL或CLI等文件格式数据，不同的文件格式数据对制作的产品精度有较大的差距，因此，研究CAD系统对快速成形设备的文件格式输出有相当重要的意义。6.模具CAD集成技术的发展趋势综上所述, 模具CAD集成技术就是应用于模具制造各个环节的计算机辅助技术和实现各环节信息集成的技术。显然,信息集成与数据统一管理是关键。产品的信息是贯穿于设计、分析、加工、检测、装配等各个阶段,实现各环节信息的流畅、解决数据格式的标准化及数据维护与共享是未来CAD集成技术发展的重点。PDM系统的出现为解决这一问题带来了曙光。PDM系统的实施是模具企业应用CAD集成技术的重要课题。在模具的设计制造方面,含有丰富专家知识的智能化模具CAD/CAM系统的研究、高速切削加工及其编程等是未来研究发展的趋势。From:Lu yiqiang,Li Dequn,Simulation of cooling process of injection molding, Progress in Natural Science,Vol.6 No.2,1996.4.毕业设计（论文）外文翻译原文The molding tool CAD Gathers the techniqueAbstract：Pass to analyze the calculator the assistance inject the mold design with make in the each link commonly shared of technique with information, this text announces to public to inject the mold CAD gathers technical and basic content, and the research heat that put forward it orders with trend.1. the plastics molding tool CAD gathers techniqueThe manufacturing of the plastics molding tool comtains the construction design of the shape design, molding tool and the number of the analysis, molding tools that include the plastics products control to process(electricity process, the line incises etc.), throw the light with go together with to try the mold and take shape manufacturing etc. quickly.The each link a CAD for involving unit technique has:The shape design( CAD) with the construction, fast anti of the product shape beg( RE), construction analysis with excellent turn the design( CAE), lend support to the manufacturing( CAM) and process the process conjecture imitate true( SIMULATION), product and molding tools take shape( RP) quickly, assistance craft process( CAPP) with product data management technique( PDM) etc.The plastics molding tool CAD gathers technique.Is to gather plastics molding tool manufacturing process a various units for involving technique get up, unify the database to deliver the format with the document, realize the information gather share with the data resources, from but shorten the design manufacturing period of the molding tool consumedly.Increases to make the mold quantity.2. the CAD design of the plastics product begs with fast anti of the shapeThe plastics molding tool that proceed the square one designs the manufacturing is the design of the a product.The traditional product design method is a design to product of three conceive outline to use two plane chart papers expresses to come out, marking clearly the craft and starting construction the method on the diagram paper.This kind of method comes to a decision the simple of a design sketch and cants control to make the quantity directly.The modern design method is a design establish the product directly on the computer of three the model of ,According to the product three models proceed the molding tool construction the design and excellent turn the design.Design according to the molding tool construction again three models proceed to process to weave the distance and establishment crafts plan.This kind of method makes product model design, molding tool construction design, process to weave distance and technological designs regard a data as the foundation, realizing the data share.Can not only increases to design the efficiency quickly, but also can guarantee the quantity, decline low cost.The source of the computer a product model has three kinds of:Making use of the CAD system software proceeds the product model the design and make use of the real object measures fast anti in proceeding beg to set up the mold and make use of the standard format document of the other the system of CAD.Source method that aim at these three kinds of products model.Have studied every kind of technique now to the design efficiency that increases product model with quantity.The underneath further analyzes every kind of technical content with the characteristics.Making use of the CAD system software proceeds the product model design.Its technique includes primarily two are several why the sketch draws, two the parameter of turn the design of the sketch, three entity shape design, three characteristic shape design, three the parameter of turn the entity shape the design, three curved face shape design, free shape in space design, the external appearance of the product exaggerates, product of dynamic advertise to design the etc.These softwareses contain many typical representatives.Two the software of design have:ME10, CADKEY, AUTOCAD, DHCAD, Genis, etc. of Sigraph; three the software of design have:UGII, PRO/ E, IDEAS, CATIA, etc. of EUCLID; free shape in product and advertise the software of the design have:Alias, etc. of CDRS.Two design are several why the sketch draws is to make use of the flat surface CAD software draw the spare parts sketch, then replace the handicraft painting with the calculator; but two the parameter of design turn.Then the calculator realizes the sketch changes the deal designs, making modification more convenient; three design shape designs is a true shape that the product that the arithmetic figure turn design, it expressed completely product.Can be further to designs for the molding tool, analysis with processes the mathematics model of the necessity of offering; the free shape in space design is the art of the product shape to design, making product been not only is a function product, but also art article.It is every kind of need that the external appearance of the product exaggerate that product of the result designs, making product more beautiful, the color can attract people more; the dynamic advertisement design of the product is a result that design to make to promote the advertisement directly the product,Proceed the market expansion.Making use of the real object measures fast anti of proceeding beg to set up mold is current investigative a little bit hot of a,It is an important technique that product imitate the type foundation go forward a line of the product modification designs.Its basic principle is to passes three coordinateses measure the machine, laser measure machine or electronicses copy the few to proceed to scan the diagraph to the real object,The data of large quantity that arithmetic figure turn that gets to measures the acquisition orders anti that send into the high class CAD software beg mold piece or appropriative anti beg the software inside, anti beg the software can read directly a data cluster,Combining can proceed the editor, filter, tidy up, beg the to a data cluster, row preface, part modification and reorganization, then automatic born curved face,It is end to acquire together the real object precision is consistent of or computer a product model that pass through reforms.This way can increases biggest new product design velocity.Current mature curved face anti beg to set up the mold software has: Surfacer.Cimatronrenge, etc. of Strim100.Make use of the standard format document of the other the system of CAD to set up the mold, this way than convenience.Because the world of the market turns with the technical development in the network of INTERNET.The CAD technique exchanges of the molding tool business enterprise with cooperate to have many pass the CAD document method proceed.Because the CAD system category is more, therefore documentary format must follow the international standard.Such as the DXF, IGES, STEP, VDA, etc. of STL.Pass to read standard format document to stablish directly or establish the product model after modifying, since can quickly, deepen the customer and the exchanges of the molding tool factory house.Also can shorten the product the design the period.3. the CAD design of the molding tool and analysisThe CAD design of the molding tool, analysis.Include to divide the type, certain type according to the product model molding tool of proceeding the design with the type, molding tool structural and detailed design, the plastics fills process analysis etc. a few aspects.Make use of the advanced characteristic shape software,such as PRO/ E, etc. of UGII, the very easily certain dividing the type,Born top and bottom mold with mold , then the proceeding flows a way, sprinkle a people and cool off the pipe line of arrange etc.Made sure these designses data hereafter, then make us e of the molding tool analysis software,Proceed such as the MOLDFLOW, CFLOW the plastics take shape the process analysis.According to the software of MOLDFOLW with it of the material, craft database of plentifulness, pass the importation take shape the craft parameter.Can the development imitate the true analysis plastics to inject in note mold the process flows the circumstance( the plastics with sprinkle a people more inject remits to flow the analysis of ), analyze the temperature pressure variety circumstance and analyze to note a remaining should dint etc.,According to analyze the circumstance to the rationality that check the molding tool construction, flow quantity problem etc. of the rationality, product of the appearance.For example whether the esse sprinkles to note the system not reasonable, appear to flow way with sprinkle a position size not appropriate.Cant equilibrium alive with type; whether to exsit product construction absurdity or molding tool constructions or not is not reasonable, appearing the product design dissatisfied( namely short shoot the phenomenon); whether to cool off asymmetry or not, the influence produces the efficiency with product quantity;Whether the esse notes the craft of wrong, appear the song of design of the product transform etc.The molding tool passes the CAD the design with analyze, can dissolve mistake at design the stage, increase to try once the mold the success the rate.At plastics molding tool design with analyze to apply many new computer-aideds technique this stage, if the parameter turns technique, characteristic shape technique, database technique etc.There is many standards piece in the plastics molding tool.Turn such as the standard mold a parameter for outing organization, sprinkling noting system, cooling system.etc. can adopting basing on database managing the characteristic shape design method proceed the design or establish the standard a design , like this since can realize the data share,Can satisfy the customer again to the at any time modifying of the design, make the design analysis of the molding tool fast, accurate, efficiently.The parameter turns the characteristic shape can not only describe the product completely then several why sketch information,And can acquire accuracy, material and assemble etc. informations of the product, its a product for establishing model is a kind of apting to handle and can reflect design intention with process the model of the characteristic.Therefore,The parameter turns the characteristic shape technique is an one of the most important technique in process in manufacturing in molding tools.4. the technical application in CAM of the molding tool, process to imitate true and manufacturingThe calculator assistance manufacturing( CAM) technique of the molding tool applies primarily in the aspects of counting to control processing, line incising to process, electricity spark processing to wait.The technique of CAM rises in the type design , type design of the complicated molding tool and the design of the electrodes process particularly more important function.Its main technique characteristics includes:(1) the design processes the knife have the track excellent to turn the programming with the instruction of NC creation,(2) the knife has the category, characteristic to establish with the material design ,(3) slicing the design process the craft parameter to really settle,(4)The commonness slices the design to slice with the high speed the characteristic that design process controls,(5) over slice the check with process the superficial accuracy control,(6) processing the computer entity of the process imitate the realistic design ,(7) The computer control number controls the technique of DNC and clusters of the machine bed control the technical and applied etc.Need the CAD specially in technical application in CAM three design product model data.More profession computer plait distance software,such as MASTERCAM, UNIMOD, etc. of CIMATRON, when the plait distance of many curved faces processes have the higher request to the curved face model of the product,Intend with the high accuracy of the curved face to match such as the directional consistency, curved face in U, V of the close together curved face, inclined rate in curved face continuous variety etc.In high class CAD/ the integral whole of CAM turn system,( such as UGII, PRO/ E).Because making use of the parameter turns the characteristic shape design with same database technique, making the type design of the product model data, molding tool have the track data to have got the inside contact with the type design model data, knife,The modification knife of the product model has the track to also modify automatically.The molding tool processes the entity imitates the true technique more and more mature, also is more and more valued by people.It is mimicry machine bed that processing the entity imitate process the process on the computer, can keep the result that view reflect process.Can takes the gauge of directly quantity that after processing spare parts, can check the mistake that process.At check quantity that after processing spare parts, can at the computer is last to process behind of the entity model proceeds the aleatoric design slices,Measure its size directly with the accuracy.Therefore, it can dissolve mistake at process the stage of craft plait distance design, reduce to repair after processing with return the work, increases consumedly the manufacturing efficiency of the molding tool with quantity.5. plastics product and its molding tools take shape the manufacturing quicklyPlastics product and its molding tools use the computer CAD technique design after completing, can pass the fleetness take shape the technique make.This is the manufacturing technique of a kind of all new concept.It abandoned the traditional machine processes the method.Its take shape principle is three design CAD entity models are long-lost set up a series of a layer data of the thickness, make use of the laser take shape machine or others take shape the equipments read these datas,Increase the method technique with the material, pile up the each layer to take shape one by one in order.This technique calls the fleetness to take shape the technique automatically.( Rapid Prototype)It is also a CAD to gather the technical importance constitutes the part.The first pedestal takes shape the equipments quickly to bear in the United States a company in 1987, because of its characteristics is to has nothing to do with the complicated degree of the product of the manufacturing, bringing the manufacturing industry the enormous vibration.Henceforth decade.Take shape quickly the technique be flown to develop soon, the category of the equipments also piles up one after another,Turn from the material the method can is divided into the laser with not the laser burns the knot method( SLS), solid surface layer shape method( SGC), layer a manufacturing method( LOM) and melt to sink to accumulate the method( FDM), district constituency glues the knot method( DSPC), laser spirit to sink to accumulate method( SALD) etc. mutually.Every kind of method characteristics is:The method of SLA is applied at the earliest stage of took shape the technique quickly, the early market occupied the bigger cent sum, but is narrow because of the mate
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