模具專業(yè)畢業(yè)設(shè)計(jì)-滾輪注塑模具設(shè)計(jì)（全套含CAD圖紙）,模具,專業(yè),畢業(yè)設(shè)計(jì),滾輪,注塑,模具設(shè)計(jì),全套,cad,圖紙 本科畢業(yè)設(shè)計(jì)（論文） （2014 屆） 本科畢業(yè)設(shè)計(jì)（論文） 題 目 名 稱： 滾輪注塑成型工藝及模具設(shè)計(jì) 學(xué) 院（部）： 專 業(yè)： 學(xué) 生 姓 名： 班 級(jí)： 學(xué)號(hào) 指導(dǎo)教師姓名： 職稱 職稱 最終評(píng)定成績(jī)： XX大學(xué)教務(wù)處  摘 要 本設(shè)計(jì)是滾輪塑料零件的注塑模具設(shè)計(jì)，在結(jié)合了傳統(tǒng)的機(jī)械設(shè)計(jì)后把CAD/CAM技術(shù)應(yīng)用在注塑模具的設(shè)計(jì)上，在CAD系統(tǒng)實(shí)行了模型和注塑模具的設(shè)計(jì)。本文介紹了我國(guó)當(dāng)前模具技術(shù)的發(fā)展?fàn)顩r以及CAD/CAM在模具上的應(yīng)用，其中包括AUTOCAD。主要的機(jī)械部分設(shè)計(jì)，其內(nèi)容包括塑料注塑模具的工作原理及應(yīng)用，設(shè)計(jì)準(zhǔn)則。塑料注塑模的設(shè)計(jì)計(jì)算，包括模具結(jié)構(gòu)設(shè)計(jì)，注塑機(jī)的選用，澆注系統(tǒng)的設(shè)計(jì)，動(dòng)、定模，澆注系統(tǒng)，脫模機(jī)構(gòu)，頂出機(jī)構(gòu)，冷卻系統(tǒng)等設(shè)計(jì)等方面。如此設(shè)計(jì)出的結(jié)構(gòu)可確保模具工作運(yùn)行可靠。 關(guān)鍵詞：CAD；CAM；注塑模；工藝 5 大學(xué)本科畢業(yè)設(shè)計(jì)（論文） ABSTRACT It is to design the holder injection mould, references to the traditional mechanical design, focus on the CAD/CAM application in the plastic mould design, that is to say to apply the CAD system in model and plastic injection mould design. This artic introduces the mould technology and the CAD/CAM application of mould in china nowadays. Including AUTOCAD，MASTERCAM. While main mechanical designs content the principle and application of the plastic mould, design standards. The calculation of the plastic mould design concerns about the mould construction design, choosing Injection Molding Machine, injection system ,the move mould, immobility mould, the irrigating system, the doffing mould organ, the goring organ, the cooling system’s design and so on. The structure designed in such way can ensure the reliable running of the mould. Keywords: CAD;CAM;PLASTIC INJECTION;MOULD 大學(xué)本科畢業(yè)設(shè)計(jì)（論文） 目 錄 摘 要 II ABSTRACT III 目 錄 IV 第1章 緒 論 1 1.1模具的作用與地位 1 1.2 本次設(shè)計(jì)研究目的及意義 1 1.3 CAD發(fā)展概況 1 1.4 注塑模CAD內(nèi)容 2 第2章 塑件的工藝分析 4 2.1塑件的工藝性分析 4 2.1.1塑件的原材料分析 4 2.1.2 聚甲醛的注塑工藝參數(shù) 4 2.2塑件的結(jié)構(gòu)和尺寸精度及表面質(zhì)量分析 6 2.2.1結(jié)構(gòu)分析 6 2.2.2尺寸精度分析 6 2.2.3表面質(zhì)量分析 6 2.3計(jì)算塑件的體積和質(zhì)量 6 第3章 注射機(jī)的選擇及校核 7 3.1 注射機(jī)的選擇 7 3.2 型腔數(shù)目的確定及校核 8 3.3 鎖模力的校核 9 3.4 開(kāi)模行程的校核 9 第4章 澆注系統(tǒng)的設(shè)計(jì) 10 4.1 分型面的選擇 10 4.2 主流道的設(shè)計(jì) 11 4.3 澆口設(shè)計(jì) 11 4.3.1 剪切速率的校核 12 4.3.2 主流道剪切速率校核 12 4.3.3 澆口剪切速率的校核 12 第5章 成型零部件設(shè)計(jì) 14 5.1 型腔和型芯工作尺寸計(jì)算 14 5.2 型腔側(cè)壁厚度計(jì)算 15 第6章 合模導(dǎo)向機(jī)構(gòu)設(shè)計(jì) 16 第7章 溫度調(diào)節(jié)系統(tǒng)設(shè)計(jì) 17 7.1 對(duì)溫度調(diào)節(jié)系統(tǒng)的要求 17 7.2 冷卻系統(tǒng)設(shè)計(jì) 17 7.2.1 設(shè)計(jì)原則 17 7.2.2 冷卻時(shí)間的確定 17 7.2.3 塑料熔體釋放的熱量 18 7.2.4 高溫噴嘴向模具的接觸傳熱 18 7.2.5 注射模通過(guò)自然冷卻傳導(dǎo)走的熱量 19 7.2.6 冷卻系統(tǒng)的計(jì)算 20 7.2.7 凹模冷卻系統(tǒng)的計(jì)算 20 第8章 模具工作原理說(shuō)明 22 總 結(jié) 23 參考文獻(xiàn) 24 致 謝 25 主要符號(hào)表 本科畢業(yè)設(shè)計(jì)（論文） 材料加工技術(shù)雜志187–188（2007）690–693 自適應(yīng)電動(dòng)溫度調(diào)節(jié)系統(tǒng) 注射成型的模具 Nardin, B. a, B. Zagar a, came, came, A. Glojek a, D. Kri, AJ BZ TECOS、工具和模具開(kāi)發(fā)中心的斯洛文尼亞,Kidriˇeva Cesta, 3000 Sloveniac Celje b教員的電氣工程,斯洛文尼亞盧布爾雅娜 摘要 在模具的開(kāi)發(fā)和生產(chǎn)過(guò)程中有一基本問(wèn)題就是是否能夠?qū)ψ⑺苣＞叩臏囟葪l件進(jìn)行控制。精確的研究在模具熱力學(xué)過(guò)程表明,換熱是可以操縱熱量的手段。這樣的系統(tǒng)升級(jí)傳統(tǒng)冷卻系統(tǒng)在模具或可以是一個(gè)獨(dú)立的應(yīng)用程序內(nèi)部熱操作。 在本文中，作者將目前的研究項(xiàng)目的結(jié)果，這是在三個(gè)階段，其結(jié)果是在A686 \ 2006專利實(shí)施專利。測(cè)試階段，原型階段和產(chǎn)業(yè)化階段將出現(xiàn)。該項(xiàng)目的主要結(jié)果是總的和快速在周期時(shí)間和整體影響重點(diǎn)變形的塑料產(chǎn)品質(zhì)量在線的模具溫度調(diào)節(jié)控制。 提出了應(yīng)用程序可以提供一個(gè)里程碑，模具溫度和產(chǎn)品質(zhì)量控制的注射成型過(guò)程中的領(lǐng)域。?2006 Elsevier B.V.保留所有權(quán)利。 關(guān)鍵詞：注射成型；模具冷卻熱電模塊；數(shù)值模擬； 1.介紹，定義的問(wèn)題 開(kāi)發(fā)技術(shù)的冷卻模具通過(guò)熱電的(TEM)意味著推導(dǎo)的工業(yè)實(shí)踐和存在的問(wèn)題,即在設(shè)計(jì)、工具制造和開(kāi)發(fā)工具。目前的冷卻技術(shù)有技術(shù)的局限性。其局限性的位置及提前預(yù)測(cè)與有限元分析(FEA)仿真包但不是完全可以避免的。結(jié)果一個(gè)多元化國(guó)家的最先進(jìn)的分析顯示,所有現(xiàn)有的冷卻系統(tǒng)不提供可控的傳熱能力足以符合要求的工藝窗口當(dāng)前聚合物加工技術(shù)。 聚合物加工是當(dāng)今有限(在任期縮短生產(chǎn)周期時(shí)間內(nèi),降低成本)只與熱容操作功能。其他生產(chǎn)優(yōu)化功能已經(jīng)驅(qū)動(dòng)機(jī)械和聚合物加工的局限性[3]。 1.1 熱過(guò)程中注塑塑料加工 塑料的處理是基于傳熱塑膠材料和模腔之間。在計(jì)算傳熱應(yīng)該考慮兩個(gè)主要事實(shí):首先是所有能源使用基于熱力學(xué)定律的第一定律節(jié)能[1],第二是速度的傳熱。在傳熱分析的基本任務(wù)是隨時(shí)間和溫度計(jì)算其分布在研究系統(tǒng)。最后取決于速度之間的熱傳導(dǎo)的系統(tǒng)和環(huán)境和速度的傳熱系統(tǒng)內(nèi)部?；趥鳠峥梢宰鳛闊醾鲗?dǎo)、對(duì)流和輻射[1]。 1.2冷卻時(shí)間 完成注射模塑過(guò)程周期由模具閉合階段,注入融化成腔,包裝壓力相位補(bǔ)償收縮效應(yīng)、冷卻階段,開(kāi)模階段和部分排出期。在大多數(shù)情況下,最長(zhǎng)時(shí)間的上述所有階段是冷卻時(shí)間。 冷卻時(shí)間在注射模塑過(guò)程被定義為時(shí)間需要冷卻塑料零件到彈射溫度[1]。 圖1 模具溫度變化在一個(gè)周期的[ 2 ] 一個(gè)冷卻過(guò)程的主要目的是降低額外冷卻時(shí)間，在理論上是不必要的；在實(shí)踐中，它延伸從45到67%的整個(gè)周期時(shí)間的[1,4]。 從文學(xué)與實(shí)驗(yàn)[1,4],它可以看到,模具溫度影響極大,因此脫模時(shí)間冷卻時(shí)間(成本)。 注射成型過(guò)程是一個(gè)循環(huán)過(guò)程,模具溫度變化見(jiàn)圖1,溫度變化從平均價(jià)值通過(guò)整體周期時(shí)間。 2.塑料注射模具冷卻技術(shù) 因?yàn)樗呀?jīng)描述,已經(jīng)有幾種不同的技術(shù),讓用戶來(lái)冷卻模具[5]。最傳統(tǒng)的方法是用鉆井技術(shù),即生產(chǎn)模具的洞。通過(guò)這些孔(coolinglines),冷卻介質(zhì)流動(dòng),消除生成和積累的熱量從模具[1,2]。它也是非常方便的在不同的材料建造,不同的熱導(dǎo)率,目的是提高控制模具溫度條件。這樣的方法是所謂的被動(dòng)方法對(duì)模具溫度控制。 這個(gè)具有挑戰(zhàn)性的任務(wù)是使一個(gè)活躍的系統(tǒng),它可以改變熱條件,對(duì)于所需的方面,比如產(chǎn)品質(zhì)量或周期時(shí)間。一個(gè)這樣的方法是集成熱電氣模塊(TEM),它可以改變熱條件期望的性質(zhì),對(duì)于模具。用這樣的方法,一個(gè)可以控制傳熱與時(shí)間和空間變量,什么手段,溫度可以調(diào)節(jié)整個(gè)注塑周期,獨(dú)立于位置的模具。熱控制是通過(guò)控制單元,輸入變量是收到的人工輸入或輸入從注塑仿真。與輸出值,控制單元模塊行為監(jiān)控TEM。 2.1 熱電模塊(TEM) 為需要的熱操作,TEM模塊集成到模具。熱量與電之間的交互變量對(duì)于換熱是基于珀?duì)柼?yīng)。珀?duì)柼?yīng)的現(xiàn)象是眾所周知的,但它是直到現(xiàn)在從未用于注塑應(yīng)用程序。TEM模塊(見(jiàn)圖2)是一個(gè)設(shè)備由妥善安排雙P和N型半導(dǎo)體,放置兩個(gè)陶瓷板之間形成熱與冷熱電冷卻器網(wǎng)站。權(quán)力的傳熱可以容易控制通過(guò)的大小和極性的電流提供。 圖2 TEM框圖 2.2 申請(qǐng)模具冷卻 應(yīng)用程序的主要想法是插入到墻壁的TEM模塊模腔作為主要傳熱單元。 這些基本的裝配中可以看到圖3。二次傳熱是通過(guò)常規(guī)流體冷卻系統(tǒng)實(shí)現(xiàn),允許熱流入與流出從模腔熱力學(xué)系統(tǒng)。 圖3 TEM冷卻組件結(jié)構(gòu) 設(shè)備呈現(xiàn)在圖。3包括熱電模塊(一個(gè)),使主要傳熱從或溫度可控表面模具腔(B)。二次傳熱是通過(guò)冷卻通道啟用(C),提供恒溫條件在模具。熱電模塊(一)操作作為熱泵和這樣操縱與熱派生或者從模具由流體冷卻系統(tǒng)(C)。系統(tǒng)二次加熱與冷卻通道操作作為熱交換器。減少熱容的可控區(qū)域保溫(D)是安裝在模腔(F)和模具結(jié)構(gòu)板(E)。 圖4 溫度的檢測(cè)與調(diào)節(jié)結(jié)構(gòu) 整個(gè)應(yīng)用程序包括TEM模塊,一個(gè)溫度傳感器和電子裝置控制系統(tǒng)的完整。該系統(tǒng)被描述在圖4和包括一個(gè)輸入單元(輸入界面)和一個(gè)供應(yīng)單位(單位為電子和電力電子供應(yīng)h橋單元)。 輸入和供應(yīng)單位與溫度傳感器回路信息附在一個(gè)控制單元,作為執(zhí)行單元試圖強(qiáng)加預(yù)定義的溫帶/時(shí)間/位置關(guān)系。使用珀?duì)柼?yīng),單位可以用于加熱或冷卻的目的。 二級(jí)除熱是通過(guò)流體冷卻媒體實(shí)現(xiàn)視為換熱器,如圖4。這單位是根據(jù)目前的冷卻技術(shù)和作為一個(gè)水槽或源的熱。這允許完全控制過(guò)程從溫度、時(shí)間和位置通過(guò)整個(gè)周期。此外,它允許不同的溫度/時(shí)間/位置概要文件在周期也為起點(diǎn)和終點(diǎn)的過(guò)程。描述技術(shù)可用于各種工業(yè)和研究目的,精確的溫度/時(shí)間/位置控制是必需的。 本文所提出的系統(tǒng)在無(wú)花果。3和4的比較分析,從理論以及實(shí)踐的觀點(diǎn)。分析了理論方面通過(guò)有限元模擬,而實(shí)用的開(kāi)發(fā)和實(shí)現(xiàn)的原型到實(shí)際應(yīng)用測(cè)試。 3.有限元分析模具冷卻 當(dāng)前的發(fā)展對(duì)注塑模具設(shè)計(jì)包括幾個(gè)階段[3]。其中還設(shè)計(jì)和優(yōu)化一個(gè)冷卻系統(tǒng)。這是現(xiàn)在由模擬使用定制的有限元軟件包(模塑仿真分析[4]),可以預(yù)測(cè)冷卻系統(tǒng)功能,特別是其影響塑料。與這種模擬,模具設(shè)計(jì)師收集信息在產(chǎn)品流變學(xué)和變形由于收縮作為魔法作為生產(chǎn)時(shí)間周期信息。 這個(gè)熱信息通常是準(zhǔn)確的,但仍然可以不可靠的情況下的流變材料信息不足。高質(zhì)量的輸入為熱調(diào)節(jié)TEM,需要得到一個(gè)圖片關(guān)于溫度分布在周期時(shí)間和整個(gè)模具表面和整個(gè)模具厚度。因此,不同的過(guò)程模擬是必要的。 圖5 在有限元環(huán)境原型截面 3.1物理模型,有限元分析 實(shí)現(xiàn)有限元分析為開(kāi)發(fā)項(xiàng)目做是由于作者長(zhǎng)期經(jīng)歷這樣的包[4]和可能性來(lái)執(zhí)行不同的測(cè)試在虛擬環(huán)境。整個(gè)冷卻系統(tǒng)設(shè)計(jì)了原型在有限元環(huán)境(見(jiàn)圖5)通過(guò)溫度分布在每個(gè)部分的原型和聯(lián)系人之間的冷卻系統(tǒng)進(jìn)行了探討。為模擬物理特性在一個(gè)樣機(jī),仿真模型構(gòu)建了利用COMSOL軟件多重物理量。結(jié)果是一個(gè)有限元模型與真實(shí)的原型(見(jiàn)圖7),通過(guò)它可以比較和評(píng)估結(jié)果。 探討了有限元模型在術(shù)語(yǔ)的傳熱物理考慮兩個(gè)熱源:水換熱器與流體物理和熱電模塊與傳熱物理(只有傳導(dǎo)和對(duì)流輻射進(jìn)行分析,忽略了由于低相對(duì)溫度,因此低影響溫度)。 有限元分析的邊界條件設(shè)定目標(biāo)達(dá)到相同的工作條件,在實(shí)際測(cè)試。周圍的空氣和水換熱器被設(shè)定在穩(wěn)定的溫度20?C。 圖6 根據(jù)有限元分析的溫度分布 有限元分析的結(jié)果中可以看到圖6,即通過(guò)模擬溫度分布區(qū)域圖5所示。圖6表示穩(wěn)態(tài)分析,非常準(zhǔn)確的原型測(cè)試相比。為了模擬時(shí)域響應(yīng)進(jìn)行了瞬態(tài)仿真也,顯示非常積極的結(jié)果對(duì)于未來(lái)的工作。才能夠?qū)崿F(xiàn)一個(gè)溫差200?C在很短的時(shí)間(5 s),可能會(huì)導(dǎo)致一些問(wèn)題在TEM結(jié)構(gòu)。這些問(wèn)題就都解決了幾個(gè)解決方案,比如足夠的安裝,選擇合適的材料和應(yīng)用智能化電子透射監(jiān)管。 3.2實(shí)驗(yàn)室測(cè)試 因?yàn)樗呀?jīng)描述,原型制作和測(cè)試(見(jiàn)圖7)。結(jié)果顯示,設(shè)置的假設(shè)被證實(shí)。用TEM模塊,可以控制溫度分布的不同部分的模具在整個(gè)周期的時(shí)間。與實(shí)驗(yàn)室測(cè)試,這是證明了的,可以是實(shí)際的熱操縱監(jiān)管與TEM模塊。測(cè)試是在實(shí)驗(yàn)室,模擬真實(shí)的工業(yè)環(huán)境,注塑成型機(jī)克勞斯Maffei公里60 C、溫度傳感器、紅外攝像機(jī)和原型TEM模塊。反應(yīng)溫度在1.8 s多樣形式+ 5 80?C,代表一個(gè)廣闊的區(qū)域內(nèi)的熱量控制在注塑周期。 圖7 在實(shí)際環(huán)境中的原型 4.結(jié)論 利用熱電模塊與它直接連接輸入和輸出之間的關(guān)系是一個(gè)里程碑冷卻應(yīng)用程序。它的引入對(duì)注塑模具與它的問(wèn)題和問(wèn)題處理的冷卻結(jié)構(gòu)精密,高質(zhì)量的塑料部分代表了很高的期望。 作者是假設(shè)使用珀?duì)柼?yīng)可用于溫度控制在模具注塑。的方法有基于仿真的工作和真正的生產(chǎn)實(shí)驗(yàn)室設(shè)備證明,假設(shè)被證實(shí)。仿真結(jié)果顯示,一個(gè)廣泛的領(lǐng)域可能的應(yīng)用TEM模塊在注塑過(guò)程。 與功能的溫度曲線提到跨周期時(shí)間,注射模塑過(guò)程可以完全控制。工業(yè)的問(wèn)題,如均勻冷卻問(wèn)題類表面及其后果的塑料件外觀可以解決。填充墻的問(wèn)題可以解決薄長(zhǎng)與過(guò)熱的一些表面在注射時(shí)間。此外,這樣的應(yīng)用程序控制流變特性的塑料材料可以獲得。用適當(dāng)?shù)臒嵴{(diào)節(jié)TEM是可能甚至控制熔體流動(dòng)的模具,在充填階段的模腔。這是做了適當(dāng)?shù)臏囟确植嫉哪＞?更高的溫度對(duì)薄壁零件的產(chǎn)品)。 應(yīng)用TEM模塊,可以顯著減少周期時(shí)間在注塑過(guò)程。時(shí)間的限制可能減少在于框架的10 - 25%的額外的冷卻時(shí)間,在1.2節(jié)描述。 應(yīng)用TEM模塊可以積極控制產(chǎn)品的翹曲和調(diào)節(jié)量的產(chǎn)品翹曲的方式來(lái)達(dá)到所需的產(chǎn)品公差。 提出了TEM模塊冷卻應(yīng)用注射模塑過(guò)程是一個(gè)優(yōu)先的選擇注意的專利,屬于TECOS舉行。 參考文獻(xiàn) [1] I. Cati′ , Izmjena topline u kalupima za injekcijsko preˇanje plastomera,sDruˇtvo plastiˇ ara i gumaraca, Zagreb, 1985.sc [2] I. Cati′ , F. Johannaber, Injekcijsko preˇanje polimera i ostalih materiala,s Druˇtvo za plastiku i gumu, Biblioteka polimerstvo, Zagreb, 2004.s [3] B. Nardin, K. Kuzman, Z. Kampuˇ, Injection moulding simulation results as an input to the injection moulding process, in: AFDM 2002: The Second International Conference on Advanced Forming and Die Manufacturing Technology, Pusan, Korea, 2002. [4] TECOS, Slovenian Tool and Die Development Centre, Mold?ow Simulation Projects 1996–2006. [5] S.C. Chen, et al., Rapid mold surface heating/cooling using electromagnetic induction technology: ANTEC 2004, Conference CD-ROM, Chicago,Illinois, 16–20 May, 2004. Journal of Materials Processing Technology 187–188 (2007) 690–693 Adaptive system for electrically driven thermoregulation of moulds for injection moulding ˇB. Nardin a,? , B. Zagar a,? , A. Glojek a , D. Kriˇ aj bz a TECOS, Tool and Die Development Centre of Slovenia, Kidriˇ eva Cesta 25, 3000 Celje, Sloveniac b Faculty of Electrical Engineering, Ljubljana, Slovenia Abstract One of the basic problems in the development and production process of moulds for injection moulding is the control of temperature con- ditions in the mould. Precise study of thermodynamic processes in moulds showed, that heat exchange can be manipulated by thermoelectrical means. Such system upgrades conventional cooling systems within the mould or can be a stand alone application for heat manipulation within it. In the paper, the authors will present results of the research project, which was carried out in three phases and its results are patented in A686\2006 patent. The testing stage, the prototype stage and the industrialization phase will be presented. The main results of the project were total and rapid on-line thermoregulation of the mould over the cycle time and overall in?uence on quality of plastic product with emphasis on deformation control. Presented application can present a milestone in the ?eld of mould temperature and product quality control during the injection moulding process. ? 2006 Elsevier B.V. All rights reserved. Keywords: Injection moulding; Mould cooling; Thermoelectric modules; FEM simulations 1. Introduction, de?nition of problem Development of technology of cooling moulds via thermo- electrical (TEM) means derives out of the industrial praxis and problems, i.e. at design, tool making and exploitation of tools. Current cooling technologies have technological limitations. Their limitations can be located and predicted in advance with ?nite element analyses (FEA) simulation packages but not com- pletely avoided. Results of a diverse state of the art analyses revealed that all existing cooling systems do not provide con- trollable heat transfer capabilities adequate to ?t into demand- ing technological windows of current polymer processing technologies. Polymer processing is nowadays limited (in term of short- ening the production cycle time and within that reducing costs) only with heat capacity manipulation capabilities. Other produc- tion optimization capabilities are already driven to mechanical and polymer processing limitations [3]. 1.1. Thermal processes in injection moulding plastic processing Plastic processing is based on heat transfer between plastic material and mould cavity. Within calculation of heat transfer one should consider two major facts: ?rst is all used energy which is based on ?rst law of thermodynamics—law of energy conservation [1], second is velocity of heat transfer. Basic task at heat transfer analyses is temperature calculation over time and its distribution inside studied system. That last depends on velocity of heat transfer between the system and surroundings and velocity of heat transfer inside the system. Heat transfer can be based as heat conduction, convection and radiation [1]. 1.2. Cooling time Complete injection moulding process cycle comprises of mould 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, the longest time of all phases described above is cooling time. Cooling time in injection moulding process is de?ned as time needed to cool down the plastic part down to ejection temperature [1]. ? Corresponding authors. Tel.: +386 3 490920; fax: +386 3 4264612. E-mail address: Blaz.Nardin@tecos.si (B. Nardin). 0924-0136/$ – see front matter ? 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.jmatprotec.2006.11.052 B. Nardin et al. / Journal of Materials Processing Technology 187–188 (2007) 690–693 691 Fig. 1. Mould temperature variation across one cycle [2]. Fig. 2. TEM block diagram. The main aim of a cooling process is to lower additional cooling time which is theoretically needless; in praxis, it extends from 45 up to 67% of the whole cycle time [1,4]. From literature and experiments [1,4], it can be seen, that the mould temperature has enormous in?uence on the ejection time and therefore the cooling time (costs). Injection moulding process is a cyclic process where mould temperature varies as shown in Fig. 1 where temperature varies from average value through whole cycle time. 2. Cooling technology for plastic injection moulds As it was already described, there are already several differ- ent technologies, enabling the users to cool the moulds [5]. The most conventional is the method with the drilling technology, i.e. producing holes in the mould. Through these holes (cooling lines), the cooling media is ?owing, removing the generated and accumulated heat from the mould [1,2]. It is also very convenient to build in different materials, with different thermal conductiv- ity with the aim to enhance control over temperature conditions in the mould. Such approaches are so called passive approaches towards the mould temperature control. The challenging task is to make an active system, which can alter the thermal conditions, regarding to the desired aspects, like product quality or cycles time. One of such approaches is integrating thermal electrical modules (TEM), which can alter the thermal conditions in the mould, regarding the desired prop- erties. With such approach, the one can control the heat transfer with the time and space variable, what means, that the temper- ature can be regulated throughout the injection moulding cycle, independent of the position in the mould. The heat control is done by the control unit, where the input variables are received from the manual input or the input from the injection moulding simulation. With the output values, the control unit monitors the TEM module behaviour. 2.1. Thermoelectric modules (TEM) For the needs of the thermal manipulation, the TEM module was integrated into mould. Interaction between the heat and elec- trical variables for heat exchange is based on the Peltier effect. The phenomenon of Peltier effect is well known, but it was until now never used in the injection moulding applications. TEM module (see Fig. 2) is a device composed of properly arranged pairs of P and N type semiconductors that are positioned between two ceramic plates forming the hot and the cold thermoelectric cooler sites. Power of a heat transfer can be easily controlled through the magnitude and the polarity of the supplied electric current. 2.2. Application for mould cooling The main idea of the application is inserting TEM module into walls of the mould cavity serving as a primary heat transfer unit. Such basic assembly can be seen in Fig. 3. Secondary heat transfer is realized via conventional ?uid cooling system that allows heat ?ows in and out from mould cavity thermodynamic system. Device presented in Fig. 3 comprises of thermoelectric modules (A) that enable primarily heat transfer from or to tem- perature controllable surface of mould cavity (B). Secondary heat transfer is enabled via cooling channels (C) that deliver constant temperature conditions inside the mould. Thermoelec- tric modules (A) operate as heat pump and as such manipulate with heat derived to or from the mould by ?uid cooling sys- tem (C). System for secondary heat manipulation with cooling channels work as heat exchanger. To reduce heat capacity of controllable area thermal insulation (D) is installed between the mould cavity (F) and the mould structure plates (E). Fig. 3. Structure of TEM cooling assembly. 692 B. Nardin et al. / Journal of Materials Processing Technology 187–188 (2007) 690–693 Fig. 4. Structure for temperature detection and regulation. The whole application consists of TEM modules, a temper- ature sensor and an electronic unit that controls the complete system. The system is described in Fig. 4 and comprises of an input unit (input interface) and a supply unit (unit for electronic and power electronic supply—H bridge unit). The input and supply units with the temperature sensor loop information are attached to a control unit that acts as an exe- cution unit trying to impose prede?ned temperate/time/position relations. Using the Peltier effect, the unit can be used for heating or cooling purposes. The secondary heat removal is realized via ?uid cooling media seen as heat exchanger in Fig. 4. That unit is based on current cooling technologies and serves as a sink or a source of a heat. This enables complete control of processes in terms of temperature, time and position through the whole cycle. Furthermore, it allows various temperature/time/position pro- ?les within the cycle also for starting and ending procedures. Described technology can be used for various industrial and research purposes where precise temperature/time/position con- trol is required. The presented systems in Figs. 3 and 4 were analysed from the theoretical, as well as the practical point of view. The theoretical aspect was analysed by the FEM simulations, while the practical one by the development and the implementation of the prototype into real application testing. 3. FEM analysis of mould cooling Current development of designing moulds for injection moulding comprises of several phases [3]. Among them is also design and optimization of a cooling system. This is nowa- days performed by simulations using customized FEM packages (Mold?ow [4]) that can predict cooling system capabilities and especially its in?uence on plastic. With such simulations, mould designers gather information on product rheology and deforma- tion due to shrinkage as ell as production time cycle information. This thermal information is usually accurate but can still be unreliable in cases of insuf?cient rheological material informa- tion. For the high quality input for the thermal regulation of TEM, it is needed to get a picture about the temperature distri- bution during the cycle time and throughout the mould surface and throughout the mould thickness. Therefore, different process simulations are needed. Fig. 5. Cross-section of a prototype in FEM environment. 3.1. Physical model, FEM analysis Implementation of FEM analyses into development project was done due to authors’ long experiences with such packages [4] and possibility to perform different test in the virtual envi- ronment. Whole prototype cooling system was designed in FEM environment (see Fig. 5) through which temperature distribution in each part of prototype cooling system and contacts between them were explored. For simulating physical properties inside a developed prototype, a simulation model was constructed using COMSOL Multiphysics software. Result was a FEM model identical to real prototype (see Fig. 7) through which it was possible to compare and evaluate results. FEM model was explored in term of heat transfer physics taking into account two heat sources: a water exchanger with ?uid physics and a thermoelectric module with heat transfer physics (only conduction and convection was analysed, radiation was ignored due to low relative temperature and therefore low impact on temperature). Boundary conditions for FEM analyses were set with the goal to achieve identical working conditions as in real test- ing. Surrounding air and the water exchanger were set at stable temperature of 20 ? C. Fig. 6. Temperature distribution according to FEM analysis. B. Nardin et al. / Journal of Materials Processing Technology 187–188 (2007) 690–693 693 Fig. 7. Prototype in real environment. Results of the FEM analysis can be seen in Fig. 6, i.e. temper- ature distribution through the simulation area shown in Fig. 5. Fig. 6 represents steady state analysis which was very accurate in comparison to prototype tests. In order to simulate the time response also the transient simulation was performed, showing very positive results for future work. It was possible to achieve a temperature difference of 200 ? C in a short period of time (5 s), what could cause several problems in the TEM structure. Those problems were solved by several solutions, such as adequate mounting, choosing appropriate TEM material and applying intelligent electronic regulation. 3.2. Laboratory testing As it was already described, the prototype was produced and tested (see Fig. 7). The results are showing, that the set assump- tions were con?rmed. With the TEM module it is possible to control the temperature distribution on different parts of the mould throughout the cycle time. With the laboratory tests, it was proven, that the heat manipulation can be practically regu- lated with TEM modules. The test were made in the laboratory, simulating the real industrial environment, with the injection moulding machine Krauss Maffei KM 60 C, temperature sen- sors, infrared cameras and the prototype TEM modules. The temperature response in 1.8 s varied form +5 up to 80 ? C, what represents a wide area for the heat control within the injection moulding cycle. 4. Conclusions Use of thermoelectric module with its straightforward con- nection between the input and output relations represents a milestone in cooling applications. Its introduction into moulds for injection moulding with its problematic cooling construction and problematic processing of precise and high quality plastic parts represents high expectations. The authors were assuming that the use of the Peltier effect can be used for the temperature control in moulds for injection moulding. With the approach based on the simulation work and the real production of laboratory equipment proved, the assump- tions were con?rmed. Simulation results showed a wide area of possible application of TEM module in the injection moulding process. With mentioned functionality of a temperature pro?le across cycle time, injection moulding process can be fully controlled. Industrial problems, such as uniform cooling of problematic A class surfaces and its consequence of plastic part appear- ance can be solved. Problems of ?lling thin long walls can be solved with overheating some surfaces at injection time. Further- more, with such application control over rheological properties of plastic materials can be gained. With the proper thermal regulation of TEM it was possible even to control the melt ?ow in the mould, during the ?lling stage of the mould cav- ity. This is done with the appropriate temperature distribution of the mould (higher temperature on the thin walled parts of the product). With the application of TEM module, it is possible to signif- icantly reduce the cycle time in the injection moulding process. The limits of possible time reduction lies in the frame of 10–25% of additional cooling time, describe in Section 1.2. With the application of TEM module it is possible to actively control the warping of the product and to regulate the amount of product warpage in the way to achieve required product tol- erances. The presented TEM module cooling application for injection moulding process is a matter of priority note for the patent, held and owned by TECOS. References ˇc[1] I. Cati′ , Izmjena topline u kalupima za injekcijsko preˇanje plastomera,s Druˇtvo plastiˇ ara i gumaraca, Zagreb, 1985.sc ˇc[2] I. Cati′ , F. Johannaber, Injekcijsko preˇanje polimera i ostalih materiala,s Druˇtvo za plastiku i gumu, Biblioteka polimerstvo, Zagreb, 2004.s [3] B. Nardin, K. Kuzman, Z. Kampuˇ, Injection moulding simulation resultss as an input to the injection moulding process, in: AFDM 2002: The Sec- ond International Conference on Advanced Forming and Die Manufacturing Technology, Pusan, Korea, 2002. [4] TECOS, Slovenian Tool and Die Development Centre, Mold?ow Simulation Projects 1996–2006. [5] S.C. Chen, et al., Rapid mold surface heating/cooling using electromag- netic induction technology: ANTEC 2004, Conference CD-ROM, Chicago, Illinois, 16–20 May, 2004.