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机械毕业设计全套

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塑料端盖毕业设计,机械毕业设计全套

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西安工业大学北方信息工程学院 毕业设计（论文）中期报告 题目： 塑料端盖注射模设计 系 别 机电信息系 专 业 机械设计制造及其自动化 班 级 B090201 姓 名 李娜 学 号 B09020138 导 师 贾建利 2013 年 3 月 16 日 nts1.设计（论文）进展状况 开题报 告之后，在老师指导下主要完成了以下工作： (1)查找与阅读论文相关的合适的英文文献，对其进行翻译并完成； (2)根据所给塑件的材料对其进行了分析，查阅塑件注塑工艺的参数； 料筒温度 : 后部 190 210 中部 200 220 前部 210 230 喷嘴 200 210 模具温度 20 40 注射压力 60 80MPa 注射周期 30 50s (3)根据中小批量生产采用一模两腔的形式； (4)初步选择注射机 XS-ZY-125，并查阅此注射机的工艺参数，如表 1 所示； 表 1 XS-ZY-125 的工艺参数 注射装置 螺杆直径 /mm 42 理论注射量 / 3cm 125 注射压力 /Mpa 120 锁模装置 锁模力 /KN 900 拉杆间距 / V)(H mm)(mm 260*290 模板行程 /mm 300 模具最小厚度 /mm 200 模具最大厚度 /mm 300 定位孔直径 /mm 100 定位孔深 /mm 30 喷嘴口直径 /mm 4 喷嘴球半径 /mm 12 顶出行程 /mm 100 顶出力 /KN 60 (5)计算单件塑件的体积和质量，计算塑件浇注系统在分型面上的投影面积，计算 锁模力，并校核所选的注射机是否满足要求 ； (6)根据分型面的选择原则确定分型面，塑件底面，既是最大截面处而且对粗糙度的要求比较低 ； (7)浇注系统的设计：为了便于流道凝料的脱出，主流道设计成圆锥形，分流道 采用梯形截面加工工艺性好，且塑料熔体的热量散失流动阻力均不大，由于直接浇口会使塑件上有明显的浇口的痕迹，侧浇口易产生熔接痕，所以采用点浇口 ,如图 2 所示 ； nts 图 1 塑件三维图 图 2 点浇口 （ 8） 侧向抽芯机构采用斜导柱形式，由于塑件有内凹，必须进行内抽，采用斜顶杆，边顶边抽； （ 9）完成了模具总装配草图的设计，如图 3、图 4 所示 。 图 3 模具总装配图草图 nts图 4 模具总装配图草图 2.存在问题及解决措施 到目前为止，在毕业设计中遇到问题如下： （ 1） 在对所选注射机校核时，计算锁模力时对塑件在分型面上的投影面积没理解； （ 2） 对浇注系统凝料的体积的计算比较模糊； （ 3） 塑件圆周分布上有侧凹，内侧 也有侧凹，只知道设计时应用侧抽芯结构，并没有真正理解在结构装配图中怎么安排； （ 4） 没有设计冷却系统，对论文所涉及的知识认识得不够深刻，所以对命题的探讨不过深入。 导致上述问题主要有两个原因，一是研究不够深入，二是撰写不够严密。针对这两个原因，解决方法有： (1)对于论文所涉及的知识多理解及学习，多查阅相关书籍； (2)对于写作过程中遇到的具体难题要多向指导老师请求援助； (3)在设计遇到问题时多和同学交流，一起探讨，共同进步； (4)自己也要对模具设计方面的知识多了解，并深刻理解，在现有的基础上提高自己，完善自 己，更好地完成设计任务。 3.后期工作安排 nts 在此后期的任务，主要是： （ 1）修改完善模具的总装配图； （ 2）根据设计计算的尺寸及所选的机构画出装配图； （ 3）完成模具零件的选材及零件图的绘制； （ 4）编写设计说明书及校核图纸，交给导师查阅； （ 5）准备答辩。 指导教师签字： 年 月 日 ntsJournal of Materials Processing Technology 187188 (2007) 690693Adaptive system for electrically driven thermoregulationof moulds for injectionB. Nardina,B.Zagara, ASlovenia,Abstractditionsmeans. mouldit.wpatent.on-line influencecontrol. 2006 Elsevier B.V. All rights reserved.K simulations1.Development of technology of cooling moulds via thermo-electrical (TEM) means derives out of the industrial praxis andproblems, i.e. at design, tool making and exploitation of tools.Current cooling technologies have technological limitations.Theirfinitepletelyretrollableingtechnologies.eningonlytionand1.1.prPlastic processing is based on heat transfer between plasticmaterial and mould cavity. Within calculation of heat transferone should consider two major facts: first is all used energy0924-0136/$doi:limitations can be located and predicted in advance withelement analyses (FEA) simulation packages but not com-avoided. Results of a diverse state of the art analysesvealed that all existing cooling systems do not provide con-heat transfer capabilities adequate to fit into demand-technological windows of current polymer processingPolymer processing is nowadays limited (in term of short-the production cycle time and within that reducing costs)with heat capacity manipulation capabilities. Other produc-optimization capabilities are already driven to mechanicalpolymer processing limitations 3.Corresponding authors. Tel.: +386 3 490920; fax: +386 3 4264612.E-mail address: Blaz.Nardintecos.si (B. Nardin).which is based on first law of thermodynamicslaw of energyconservation 1, second is velocity of heat transfer. Basic taskat heat transfer analyses is temperature calculation over timeand its distribution inside studied system. That last depends onvelocity of heat transfer between the system and surroundingsand velocity of heat transfer inside the system. Heat transfer canbe based as heat conduction, convection and radiation 1.1.2. Cooling timeComplete injection moulding process cycle comprises ofmould closing phase, injection of melt into cavity, packing pres-sure phase for compensating shrinkage effect, cooling phase,mould opening phase and part ejection phase. In most cases, thelongest time of all phases described above is cooling time.Cooling time in injection moulding process is defined astime needed to cool down the plastic part down to ejectiontemperature 1. see front matter 2006 Elsevier B.V. All rights reserved.10.1016/j.jmatprotec.2006.11.052aTECOS, Tool and Die Development Centre ofbFaculty of Electrical EngineeringOne of the basic problems in the development and production processin the mould. Precise study of thermodynamic processes in mouldsSuch system upgrades conventional cooling systems within theIn the paper, the authors will present results of the research project, whichThe testing stage, the prototype stage and the industrialization phasethermoregulation of the mould over the cycle time and overallPresented application can present a milestone in the field of mould temperatureeywords: Injection moulding; Mould cooling; Thermoelectric modules; FEMIntroduction, definition of problemmoulding. Glojeka,D.KrizajbKidriceva Cesta 25, 3000 Celje, Slovenia, Ljubljana, Sloveniaof moulds for injection moulding is the control of temperature con-showed, that heat exchange can be manipulated by thermoelectricalor can be a stand alone application for heat manipulation withinas carried out in three phases and its results are patented in A6862006will be presented. The main results of the project were total and rapidon quality of plastic product with emphasis on deformationand product quality control during the injection moulding process.Thermal processes in injection moulding plasticocessingntsB. Nardin et al. / Journal of Materials Processing Technology 187188 (2007) 690693 691coolingfrommouldandtemperaturefrom2.entmosti.e.lines),accumulatedtoityintoalterlikintetheerties.withatureindependentdonefromsimulation.TEM2.1.wtricalTheFig. 2. TEM block diagram.now never used in the injection moulding applications. TEMmodule (see Fig. 2) is a device composed of properly arrangedpairs of P and N type semiconductors that are positioned betweentwo ceramic plates forming the hot and the cold thermoelectriccooler sites. Power of a heat transfer can be easily ounit.transferallosystem.modulesperatureheatconstanttricwithtemchannelscontrollablemouldFig. 1. Mould temperature variation across one cycle 2.The main aim of a cooling process is to lower additionaltime which is theoretically needless; in praxis, it extends45 up to 67% of the whole cycle time 1,4.From literature and experiments 1,4, it can be seen, that thetemperature has enormous influence on the ejection timetherefore the cooling time (costs).Injection moulding process is a cyclic process where mouldvaries as shown in Fig. 1 where temperature variesaverage value through whole cycle time.Cooling technology for plastic injection mouldsAs it was already described, there are already several differ-technologies, enabling the users to cool the moulds 5. Theconventional is the method with the drilling technology,producing holes in the mould. Through these holes (coolingthe cooling media is flowing, removing the generated andheat from the mould 1,2. It is also very convenientbuild in different materials, with different thermal conductiv-with the aim to enhance control over temperature conditionsthe mould. Such approaches are so called passive approacheswards the mould temperature control.The challenging task is to make an active system, which canthe thermal conditions, regarding to the desired aspects,e product quality or cycles time. One of such approaches isgrating thermal electrical modules (TEM), which can alterthermal conditions in the mould, regarding the desired prop-With such approach, the one can control the heat transferthe time and space variable, what means, that the temper-can be regulated throughout the injection moulding cycle,of the position in the mould. The heat control isby the control unit, where the input variables are receivedthe manual input or the input from the injection mouldingWith the output values, the control unit monitors themodule behaviour.Thermoelectric modules (TEM)For the needs of the thermal manipulation, the TEM moduleas integrated into mould. Interaction between the heat and elec-variables for heat exchange is based on the Peltier effect.phenomenon of Peltier effect is well known, but it was untilthe magnitude and the polarity of the supplied electricApplication for mould coolingThe main idea of the application is inserting TEM modulewalls of the mould cavity serving as a primary heat transferSuch basic assembly can be seen in Fig. 3. Secondary heatis realized via conventional fluid cooling system thatws heat flows in and out from mould cavity thermodynamicDevice presented in Fig. 3 comprises of thermoelectric(A) that enable primarily heat transfer from or to tem-controllable surface of mould cavity (B). Secondarytransfer is enabled via cooling channels (C) that delivertemperature conditions inside the mould. Thermoelec-modules (A) operate as heat pump and as such manipulateheat derived to or from the mould by fluid cooling sys-(C). System for secondary heat manipulation with coolingwork as heat exchanger. To reduce heat capacity ofarea thermal insulation (D) is installed between thecavity (F) and the mould structure plates (E).Fig. 3. Structure of TEM cooling assembly.nts692 B. Nardin et al. / Journal of Materials Processing Technology 187188 (2007) 690693aturesystem.inputandinformationcutionrelations.ormediacurrentofofFurthermore,filesDescribedresearchtroltheoretical,aspectoneinto3.mouldingdesigndays(Moldfloespeciallydesignerstionunreliabletion.TEM,bandsimulationsFig. 5. Cross-section of a prototype in FEM environment.3.1. Physical model, FEM analysisImplementation of FEM analyses into development projectwas done due to authors long experiences with such packages4 and possibility to perform different test in the virtual envi-ronment.eninthemdeCOMSOLidenticalpossibletakingfluidphysicswimpactgoaling.temperatureFig. 4. Structure for temperature detection and regulation.The whole application consists of TEM modules, a temper-sensor and an electronic unit that controls the completeThe system is described in Fig. 4 and comprises of anunit (input interface) and a supply unit (unit for electronicpower electronic supplyH bridge unit).The input and supply units with the temperature sensor loopare attached to a control unit that acts as an exe-unit trying to impose predefined temperate/time/positionUsing the Peltier effect, the unit can be used for heatingcooling purposes.The secondary heat removal is realized via fluid coolingseen as heat exchanger in Fig. 4. That unit is based oncooling technologies and serves as a sink or a sourcea heat. This enables complete control of processes in termstemperature, time and position through the whole cycle.it allows various temperature/time/position pro-within the cycle also for starting and ending procedures.technology can be used for various industrial andpurposes where precise temperature/time/position con-is required.The presented systems in Figs. 3 and 4 were analysed from theas well as the practical point of view. The theoreticalwas analysed by the FEM simulations, while the practicalby the development and the implementation of the prototypereal application testing.FEM analysis of mould coolingCurrent development of designing moulds for injectioncomprises of several phases 3. Among them is alsoand optimization of a cooling system. This is nowa-performed by simulations using customized FEM packagesw 4) that can predict cooling system capabilities andits influence on plastic. With such simulations, mouldgather information on product rheology and deforma-due to shrinkage as ell as production time cycle information.This thermal information is usually accurate but can still bein cases of insufficient rheological material informa-For the high quality input for the thermal regulation ofit is needed to get a picture about the temperature distri-ution during the cycle time and throughout the mould surfacethroughout the mould thickness. Therefore, different processare needed.Whole prototype cooling system was designed in FEMvironment (see Fig. 5) through which temperature distributioneach part of prototype cooling system and contacts betweenwere explored. For simulating physical properties inside aveloped prototype, a simulation model was constructed usingMultiphysics software. Result was a FEM modelto real prototype (see Fig. 7) through which it wasto compare and evaluate results.FEM model was explored in term of heat transfer physicsinto account two heat sources: a water exchanger withphysics and a thermoelectric module with heat transfer(only conduction and convection was analysed, radiationas ignored due to low relative temperature and therefore lowon temperature).Boundary conditions for FEM analyses were set with theto achieve identical working conditions as in real test-Surrounding air and the water exchanger were set at stableof 20C.Fig. 6. Temperature distribution according to FEM analysis.ntsB. Nardin et al. / Journal of Materials Processing Technology 187188 (2007) 690693 693atureFig.inresponsevtemperaturewhatproblemsmounting,intelligent3.2.testedtionscontrolmouldwlatedsimulatingmouldingsors,temperaturerepresentsmoulding4.nectionmilestone in cooling applications. Its introduction into mouldsfor injection moulding with its problematic cooling constructionand problematic processing of precise and high quality plasticparts represents high expectations.The authors were assuming that the use of the Peltier effectcan be used for the temperature control in moulds for injectionmoulding. With the approach based on the simulation work andthe real production of laboratory equipment proved, the assump-tions were confirmed. Simulation results showed a wide area ofpossible application of TEM module in the injection mouldingprocess.With mentioned functionality of a temperature profile acrosscycle time, injection moulding process can be fully controlled.Industrial problems, such as uniform cooling of problematicAancesolvmore,ofrefloityofproduct).icantlyTheofcontroloferances.mouldingandRefer123Fig. 7. Prototype in real environment.Results of the FEM analysis can be seen in Fig. 6, i.e. temper-distribution through the simulation area shown in Fig. 5.6 represents steady state analysis which was very accuratecomparison to prototype tests. In order to simulate the timealso the transient simulation was performed, showingery positive results for future work. It was possible to achieve adifference of 200C in a short period of time (5 s),could cause several problems in the TEM structure. Thosewere solved by several solutions, such as adequatechoosing appropriate TEM material and applyingelectronic regulation.Laboratory testingAs it was already described, the prototype was produced and(see Fig. 7). The results are showing, that the set assump-were confirmed. With the TEM module it is possible tothe temperature distribution on different parts of thethroughout the cycle time. With the laboratory tests, itas proven, that the heat manipulation can be practically regu-with TEM modules. The test were made in the laboratory,the real industrial environment, with the injectionmachine Krauss Maffei KM 60 C, temperature sen-infrared cameras and the prototype TEM modules. Theresponse in 1.8 s varied form +5 up to 80C, whata wide area for the heat control within the injectioncycle.ConclusionsUse of thermoelectric module with its straightforward con-between the input and output relations represents a45class surfaces and its consequence of plastic part appear-can be solved. Problems of filling thin long wa