水筆套注塑模具的設(shè)計(jì)【圓珠筆套】【一模十二腔】【說明書+CAD】
水筆套注塑模具的設(shè)計(jì)【圓珠筆套】【一模十二腔】【說明書+CAD】,圓珠筆套,一模十二腔,說明書+CAD,水筆套注塑模具的設(shè)計(jì)【圓珠筆套】【一模十二腔】【說明書+CAD】,水筆,注塑,模具,設(shè)計(jì),圓珠筆,十二,12,說明書,仿單,cad
題 目:水筆套注塑模的設(shè)計(jì)副 標(biāo) 題:I緒論摘 要 日用品,有時(shí)采用精度和強(qiáng)度不太高的塑料注塑,由于塑料具有可塑性強(qiáng),密度小、比強(qiáng)度高、結(jié)緣性、化學(xué)穩(wěn)定性高、外觀多樣的特點(diǎn),因而受到越來越多的廠家及人民的喜愛。塑料工業(yè)是新興的工業(yè),是隨著石油工業(yè)的發(fā)展而應(yīng)而生的,目前塑料制件幾乎已經(jīng)進(jìn)入一切工業(yè)部門以及人民日常生活的各個(gè)領(lǐng)域。隨著機(jī)械工業(yè)電子工業(yè),航空工業(yè)、儀器儀表工業(yè)和日常用品工業(yè)的發(fā)展,塑料成型制件的需求量越來越多,質(zhì)量要求也越來越高,這就要求成型塑件的模具的開發(fā),設(shè)計(jì)制造的水平也須越來越高。本文也就對(duì)日用品中的水筆套模具設(shè)計(jì)過程進(jìn)行闡述。關(guān)鍵詞: 水筆套 注塑模I目 錄目 錄摘 要I目 錄I1. 緒論11.1塑料成型在工業(yè)生產(chǎn)中的重要性11.1.1塑料及塑料工業(yè)的發(fā)展11.1.2塑料成型在工業(yè)生產(chǎn)中的重要作用11.1.3 塑料成型技術(shù)的發(fā)展趨勢(shì)12. 塑件成型工藝分析23. 塑件在模具中位置的設(shè)計(jì)33.1 分型面的選擇34. 普通澆注系統(tǒng)設(shè)計(jì)44.1 澆注系統(tǒng)的組成及設(shè)計(jì)原則44.2 主流道與分流道設(shè)計(jì)44.2.1主流道的設(shè)計(jì)44.3 澆口設(shè)計(jì)54.4 拉料桿設(shè)計(jì)54.5 排氣系統(tǒng)設(shè)計(jì)65. 成型零件設(shè)計(jì)65.1 成型零件結(jié)構(gòu)設(shè)計(jì)65.2 成型零件工作尺寸計(jì)算65.2.1 型腔、型芯工作尺寸計(jì)算65.3 成型零件剛度與強(qiáng)度計(jì)算65.3.1 剛度校核65.3.2 強(qiáng)度校核76. 塑料注塑模結(jié)構(gòu)零部件設(shè)計(jì)76.1 合模導(dǎo)向機(jī)構(gòu)的設(shè)計(jì)76.2 支承板設(shè)計(jì)76.3 墊塊設(shè)計(jì)77. 溫度調(diào)節(jié)系統(tǒng)的設(shè)計(jì)(冷卻系統(tǒng))87.1 冷卻回路尺寸的確立及布置88.脫模機(jī)構(gòu)的設(shè)計(jì)(推出機(jī)構(gòu))88.1 推桿設(shè)計(jì)88.2 復(fù)位桿設(shè)計(jì)89.確定注塑機(jī)型號(hào)99.1 注塑機(jī)的選擇99.2 開模行程的校核109.3 模具在注塑機(jī)上的安裝1010.模具總裝圖11致謝12參考文獻(xiàn)13II水筆套注塑模設(shè)計(jì)1. 緒論1.1塑料成型在工業(yè)生產(chǎn)中的重要性1.1.1塑料及塑料工業(yè)的發(fā)展 塑料是以樹脂為主要成分的高分子有機(jī)化合物,簡(jiǎn)稱高聚物。塑料其余成分包括增塑劑、穩(wěn)定劑、增強(qiáng)劑、固化劑、填料及其它配合劑。塑料制件在工業(yè)中應(yīng)用日趨普遍,這是由于它的一系列特殊的優(yōu)點(diǎn)決定的。塑料密度小、質(zhì)量輕。塑料比強(qiáng)度高;絕緣性能好,介電損耗低,是電子工業(yè)不可缺少的原材料;塑料的化學(xué)穩(wěn)定性高,對(duì)酸、堿和許多化學(xué)藥品都有很好的耐腐蝕能力;塑料還有很好的減摩、耐磨及減震、隔音性能也較好。因此,塑料躋身于金屬、纖維材料和硅酸鹽三大傳統(tǒng)材料之列,在國民經(jīng)濟(jì)中,塑料制件已成為各行各業(yè)不可缺少的重要材料之一。塑料工業(yè)的發(fā)展階段大致分為一下及個(gè)階段:初創(chuàng)階段 30年代以前,科學(xué)家研制分醛、硝酸纖維和聚酰胺等熱塑料,他們的工業(yè)化特征是采用間歇法、小批量生產(chǎn)。發(fā)展階段 30年代,低密度聚乙烯、聚氯乙烯等塑料的工業(yè)化生產(chǎn),奠定了塑料工業(yè)的基礎(chǔ),為其進(jìn)一步發(fā)展開辟了道路。飛躍階段 50年代中期到60年代末,塑料的產(chǎn)量和數(shù)量不斷增加,成型技術(shù)更趨于完善。穩(wěn)定增長(zhǎng)階段 70年代以來,通過共聚、交聯(lián)、共混、復(fù)合、增強(qiáng)、填充和發(fā)泡等方法來改進(jìn)塑料性能,提高產(chǎn)品質(zhì)量,擴(kuò)大應(yīng)用領(lǐng)域,生產(chǎn)技術(shù)更趨合理。塑料工業(yè)向著自動(dòng)化、連續(xù)化、產(chǎn)品系列化,以及不拓寬功能性和塑料的新領(lǐng)域發(fā)展。我國塑料工業(yè)發(fā)展較晚。50年代末,由于萬噸級(jí)聚氯乙稀裝置的投產(chǎn)和70年代中期引進(jìn)石油化工裝置的建成投產(chǎn),使塑料工業(yè)有了兩次的躍進(jìn),于此同時(shí),塑料成型加工機(jī)械和工藝方法也得到了迅速的發(fā)展,各種加工工藝都已經(jīng)齊全。塑料由于其不斷的被開發(fā)和應(yīng)用,加之成型工藝的不斷發(fā)展成熟于完善,極大地促進(jìn)了成型模具的開發(fā)于制造。隨著工工業(yè)塑料制件和日用塑料制件的品種和需求的日益增加,而且產(chǎn)品的更新?lián)Q代周期也越來越短,對(duì)塑料和產(chǎn)量和質(zhì)量提出了越來越高的要求。1.1.2塑料成型在工業(yè)生產(chǎn)中的重要作用模具是工業(yè)生產(chǎn)中重要的工藝裝備,模具工業(yè)是國民經(jīng)濟(jì)各部門發(fā)展的重要基礎(chǔ)之一。塑料模是指用于成型塑料制件的模具,它是型腔模的一種類型。模具設(shè)計(jì)水平的高低、加工設(shè)備的好壞、制造力量的強(qiáng)弱、模具質(zhì)量的好壞,直接影響著許多新產(chǎn)品的開發(fā)和老產(chǎn)品的更新?lián)Q代,影響著產(chǎn)品質(zhì)量和經(jīng)濟(jì)效益的提高。美國工業(yè)界認(rèn)為“模具工業(yè)是美國工業(yè)的基礎(chǔ)”,日本則稱“模具是促進(jìn)社會(huì)繁榮富裕的勞動(dòng)力”。近年來,我國各行業(yè)對(duì)模具的發(fā)展都非常重視。1989年,國務(wù)院頒布了“當(dāng)前產(chǎn)業(yè)政策要點(diǎn)的決定”,在重點(diǎn)支持改造的產(chǎn)業(yè)、產(chǎn)品中,把模具制造列為機(jī)械技術(shù)改造序列的第一位,它確定了模具工業(yè)在國民經(jīng)濟(jì)中的重要地位,也提出了振興模具工業(yè)的主要任務(wù)。1.1.3 塑料成型技術(shù)的發(fā)展趨勢(shì)一副好的塑料模具與模具的設(shè)計(jì)、模具材料及模具制造有很大的關(guān)系。塑料成型技術(shù)發(fā)展趨勢(shì)可以簡(jiǎn)單地歸納為一下幾個(gè)方面:模具的標(biāo)準(zhǔn)化 為了適應(yīng)大規(guī)模成批生產(chǎn)塑料成型模具和縮短模具制造周期的需要,模具的標(biāo)準(zhǔn)化工作十分重要,目前我國標(biāo)準(zhǔn)化程度只達(dá)到20。注射模具零部件、模具技術(shù)條件和標(biāo)準(zhǔn)模架等有一下14個(gè)標(biāo)準(zhǔn):當(dāng)前的任務(wù)是重點(diǎn)研究開發(fā)熱流道標(biāo)準(zhǔn)元件和模具溫控標(biāo)準(zhǔn)裝置;精密標(biāo)準(zhǔn)模架、精密導(dǎo)向件系列;標(biāo)準(zhǔn)模板及模具標(biāo)準(zhǔn)件的先進(jìn)技術(shù)和等向標(biāo)準(zhǔn)化模塊等。加強(qiáng)理論研究;塑料制件的精密化、微型化和超大型化;新材料、新技術(shù)、新工藝的研制、開發(fā)和應(yīng)用;各種新材料的研制和應(yīng)用,模具加工技術(shù)的革新,CAD/CAM/CAE技術(shù)的應(yīng)用都是模具設(shè)計(jì)制造的發(fā)展趨勢(shì)。2. 塑件成型工藝分析圖1 水筆套零件圖圖2-2 水筆套塑件圖圖2塑具材料為ABS塑料(丙烯腈-丁二烯-苯乙烯共聚物)查表得收縮率為:0.3%-0.8%,取值0.4%;大批量生產(chǎn)塑件材料特性:ABS塑料是在聚苯乙烯分子中導(dǎo)入了丙烯腈、丁二烯等異種單體后成為的改性共聚物,也可稱改性聚苯乙烯,具有比聚苯乙烯更好的使用和工藝性能。ABS是一種常用的具有良好的綜合力學(xué)性能的工程塑料。ABS塑料一般不透明。ABS 無毒、無味,成形塑件的表面有較好的光澤。ABS具有良好的機(jī)械強(qiáng)度,特別是抗沖擊強(qiáng)度高。ABS還具有一定的耐磨性、耐寒性、耐油性、耐水性、化學(xué)穩(wěn)定性和電性能。缺點(diǎn):耐熱性不高,且耐氣候性較差,在紫外線作用下易變硬發(fā)脆。塑件材料成形特性:使用ABS注射成形塑料制品時(shí),由于其熔體黏度較高,所需要的注射成形壓力較高,因此塑件對(duì)型芯的包緊力較大,故塑件應(yīng)采用較大的脫模斜度。另外熔體黏度較高,使ABS制品易產(chǎn)生熔接痕,所以模具設(shè)計(jì)時(shí)應(yīng)注意盡量減少澆注系統(tǒng)對(duì)料流的阻力。ABS易吸水,成形加工前應(yīng)進(jìn)行干燥處理。在正常的成形條件下,ABS制品的尺寸穩(wěn)定性較好。在正常的成型條件下壁厚,熔料溫度對(duì)收縮率影響極小,在要求塑件精度高時(shí),模具溫度可控制在5060C,而在強(qiáng)調(diào)塑件光澤和耐熱時(shí),模具溫度應(yīng)控制在6080C。據(jù)該塑件分析得到以下結(jié)果1)該塑件尺寸較小,一般精度等級(jí)4,為降低成本,采用一模多腔,并不對(duì)制品進(jìn)行后加工。2)根據(jù)塑件的生產(chǎn)效率及為提高成型效率采用側(cè)澆口。 3)為了方便加工和熱處理,型腔與型芯采用拼鑲結(jié)構(gòu)。確定型腔:尺寸精度等級(jí)要求一般, 采用一模12腔。據(jù)圖 1塑料件圖示尺寸(圓角等部位簡(jiǎn)化)近似計(jì)算:水筆套體積 Vs1.37cm3 查相關(guān)手冊(cè)得:塑料ABS的密度為1.021.20g/cm3 本文取1.05 g/cm3單件塑件重量 Ms=Vs=0.1941.051.78g3. 塑件在模具中位置的設(shè)計(jì)3.1 分型面的選擇根據(jù)分型面的設(shè)計(jì)原則,1)分型面應(yīng)該選在塑件的最大輪廓處2)分型面的選擇應(yīng)有利于塑件的順利脫模3)分型面的選擇應(yīng)保證塑件的精度要求4)分型面的選擇應(yīng)滿足塑件的外觀質(zhì)量要求5)分型面的選擇要便于模具的加工制造6 )分型面的選擇應(yīng)有利于排氣綜合上面幾點(diǎn)故分型面如下圖圖34. 普通澆注系統(tǒng)設(shè)計(jì)4.1 澆注系統(tǒng)的組成及設(shè)計(jì)原則普通澆注系統(tǒng)由主流道分流道澆口和冷料井組成,它有以下設(shè)計(jì)原則1) 排氣性良好;2) 流程短;3) 防止型芯變形;4) 塑件在成型后的整修方便;5) 防止因澆注系統(tǒng)不當(dāng)而造成制品變形或開裂6) 澆注系統(tǒng)的容積,在保證工作順利的條件下,應(yīng)取最小值,以減少材料的損耗。4.2 主流道與分流道設(shè)計(jì)4.2.1主流道的設(shè)計(jì) 主流道是指澆注系統(tǒng)中從注射機(jī)噴嘴與模具接觸出開始到分流道為止的塑料體的流動(dòng)通道,根據(jù)模具設(shè)定為一模8腔,可以估計(jì)一次成型所需的塑料,因此可確定型號(hào)為注射機(jī)XS-Z-30,結(jié)合廠里實(shí)際應(yīng)用情況,及模架的選擇及剛度與強(qiáng)度要求澆口套設(shè)計(jì)如下:主流道設(shè)計(jì)成圓錐型,其錐角為2060,內(nèi)壁粗糙度Ra取1.6m。分流道截面設(shè)計(jì)成圓形截面加工容易,且熱量損失與壓力損失均不大,為常用形式。圓形截面分流道的直徑可根據(jù)塑件的流動(dòng)性良好,所以造圓形截面。根據(jù)經(jīng)驗(yàn)分流道的直徑d可取46mm。4.2.2分流道的設(shè)計(jì) 在設(shè)計(jì)多型腔或者多澆口的單型腔的澆注系統(tǒng)時(shí)應(yīng)設(shè)置分流道,考慮到U形截面加工較容易,而且熱量損失與壓力損失均不大,故為所選,根據(jù)經(jīng)驗(yàn)值分流道寬度為3.2-9.5才是合理的,故分道流道寬度b=4mm,半徑R=b/2=2,深度h=1.252=2.5,為了能夠使塑料流動(dòng)平衡均勻,使排列緊湊流程盡量短,使脹模力的中心與注射機(jī)鎖模力中心一致。圖44.3 澆口設(shè)計(jì)為了提高成型效率,采用潛伏式側(cè)澆口。澆口位置可以根據(jù)經(jīng)驗(yàn)公式計(jì)算n=0.8W=nA/301mm t=0.8=0.81.3=1mm W-側(cè)向澆口之寬(mm) A-型腔一側(cè)表面積(等于v/t)(mm2) T和為塑件在澆口位置處的 壁厚.4.4 拉料桿設(shè)計(jì)拉料桿的作用是注射結(jié)束模具分型時(shí),將主流凝料從定模澆口套中拉出,最后推出機(jī)構(gòu)開始工作,將塑件和澆注系統(tǒng)冷料一起推出模外。該塑件表面光滑無刮痕等缺陷,如果采用自動(dòng)脫落,塑件脫落表面相互撞將造成表面刮痕等缺陷,因此該模具采用Z字形拉料桿,如圖所示。工作時(shí)依靠Z字形鉤將主流道凝料拉出澆口套。圖54.5 排氣系統(tǒng)設(shè)計(jì)利用配合間隙排氣,這是最常見的,也是最經(jīng)濟(jì)的,更是具有使用性的。利用滑塊和導(dǎo)滑槽配合間隙便可以排氣,所以這里無須開排氣槽。5. 成型零件設(shè)計(jì)5.1 成型零件結(jié)構(gòu)設(shè)計(jì)根據(jù)成型零件結(jié)構(gòu)設(shè)計(jì)的特征,結(jié)合筆套的形狀簡(jiǎn)單、體積小,決定采用圓形凹模整體式5.2 成型零件工作尺寸計(jì)算5.2.1 型腔、型芯工作尺寸計(jì)算 型腔內(nèi)形尺寸 Lm =(1+S)ls-3/4 + z 0 型腔深度尺寸 Hm =(1+S)hs-2/3 + z 0 型芯外形尺寸 lm =(1+S)Ls+3/4 -z0 型芯高度尺寸 hm =(1+S)Hs+2/3 -z0式中 lS 塑件外型徑向基本尺寸的最大尺寸(mm) ;LS 塑件內(nèi)型徑向基本尺寸的最小尺寸(mm) ;hS 塑件外型高度基本尺寸的最大尺寸(mm) ;HS 塑件內(nèi)型深度基本尺寸的最小尺寸(mm) ; 制品公差或偏差(mm) ;Z 成型零件制造公差,?。?/31/4) 。型腔尺寸計(jì)算尺寸 公差值/mm 計(jì)算14 0.38 Lm =(1+0.65%)14-0.750.38 0+0.127=13.8060+0.1273.5 0.26 Lm =(1+0.65%)3.5-0.750.26 0+0.087=3.3277 0+0.08751 0.12 Hm =(1+0.65%)51-2/30.12 0+0.040=51.2415 0+0.040型芯尺寸計(jì)算 尺寸 公差值/mm 計(jì)算 8.5 0.26 lm =(1+0.65%)8.5+0.750.260-0.087=8.750-0.08740 0.16 Hm =(1+0.65%)40+0.750.16 0-0.053=40.380-0.0535.3 成型零件剛度與強(qiáng)度計(jì)算5.3.1 剛度校核s1.15式中 E鋼材料彈性模量,取2.06105Mpa; S側(cè)壁厚度 P型腔內(nèi)熔體壓力根據(jù)查表結(jié)果得出=0.05mmP取30Mpa,代入計(jì)算得出結(jié)果191.15,成立故能滿足其剛度要求。5.3.2 強(qiáng)度校核sr(式中 型腔材料許用拉應(yīng)力為150Mpa 代入計(jì)算得出19r( (成立故能滿足其強(qiáng)度要求,確定最小壁厚之后,結(jié)合模具抽芯原則,初步確定選用A3型模架,模架周邊尺寸為250160。6. 塑料注塑模結(jié)構(gòu)零部件設(shè)計(jì)6.1 合模導(dǎo)向機(jī)構(gòu)的設(shè)計(jì)合模導(dǎo)向機(jī)構(gòu)是保證動(dòng)、定模和模時(shí),正確地定位和導(dǎo)向的零件。導(dǎo)向機(jī)構(gòu)起著定位、導(dǎo)向作用以及承受一定的側(cè)壓力。該模具導(dǎo)柱為帶頭導(dǎo)柱165025 GB/T4169.41984,導(dǎo)柱的材料為T8,淬硬到HRC5055 ;該模具導(dǎo)套為直導(dǎo)套1625 GB/T4169.31984,導(dǎo)套的材料為T8,淬硬到HRC5055。6.2 支承板設(shè)計(jì)支承板的作用是承受成型塑料薄膜熔體對(duì)動(dòng)模型腔或型芯的作用力,以防止型腔底部產(chǎn)生過大的撓曲變形或防止主型芯脫出型芯固定板。對(duì)支承板的設(shè)計(jì)要求應(yīng)具有較高的平行度和必要的硬度和強(qiáng)度。支承板的厚度計(jì)算 t5pbL4/32EB1/3式中 h 支承板的厚度(mm) ; p 承受的注射壓力(MPa) ; L 支承板跨度(mm) ; b 支承板受力的寬度(mm); E 剛的彈性模量,取2.06105Mpa ; 允許的變形量(mm) ; B 支承板的寬度。 t52072964/322.061052500.061/3 mm18.356 mm由上面所計(jì)算的數(shù)值可知支承板厚度18.356mm ,取20mm 。該模具支承板取16025020 GB/T4169.819846.3 墊塊設(shè)計(jì)墊塊的作用是支承動(dòng)模成型部分并形成推出機(jī)構(gòu)運(yùn)動(dòng)空間的零件。其中相關(guān)尺寸根據(jù)模架以及推出高度而定,取2503250 GB/T4169.61984。7. 溫度調(diào)節(jié)系統(tǒng)的設(shè)計(jì)(冷卻系統(tǒng))7.1 冷卻回路尺寸的確立及布置由于冷卻水道的位置、結(jié)構(gòu)形式、孔徑、表面狀態(tài)、水的流速、模具材料等很多因素都會(huì)影響模具的冷卻,因此用塑件的平均壁厚來確定水孔直徑。塑件平均壁厚為1.6mm ,尺寸較小,確定水孔直徑為8mm 。通過調(diào)節(jié)水溫、水速來滿足要求。8.脫模機(jī)構(gòu)的設(shè)計(jì)(推出機(jī)構(gòu))推出機(jī)構(gòu)一般由推出、復(fù)位和導(dǎo)向三大部件組成,推出機(jī)構(gòu)按其推出動(dòng)作的動(dòng)力來源可分為手動(dòng)推出機(jī)構(gòu)、機(jī)動(dòng)推出機(jī)構(gòu)、和液壓與氣動(dòng)推出機(jī)構(gòu)等,按模具的結(jié)構(gòu)特征可分為一次推出機(jī)構(gòu)、二次推出機(jī)構(gòu)、定模推出機(jī)構(gòu)等等一次推出機(jī)構(gòu)又稱簡(jiǎn)單推出機(jī)構(gòu),它是指開模后在動(dòng)模一側(cè)用一次推出動(dòng)作完成塑件的推出。一次推出機(jī)構(gòu),包括推桿推出機(jī)構(gòu),推管推出機(jī)構(gòu),推件板推出機(jī)構(gòu)等等。由于設(shè)置推桿的自由度較大,且截面大部分為圓形,制造維修方便、推出動(dòng)作靈活可靠,推出時(shí)運(yùn)動(dòng)阻力小,便于跟換,結(jié)合模架的選擇綜合各方面因素考慮,推桿推出機(jī)構(gòu)應(yīng)該是首選。8.1 推桿設(shè)計(jì)根據(jù)推桿位置的選擇要求:推桿的位置應(yīng)該選擇在脫模阻力最大的位置,當(dāng)塑件各處的脫模阻力相同時(shí)需要均勻布置、推桿位置選擇時(shí)應(yīng)注意塑件本身的強(qiáng)度與剛度,推桿裝入模具后,其端面應(yīng)與型腔底面平齊,或高出型腔0.05-0.1mm,考慮冷料穴中有較多的塑料,根據(jù)各模板的厚度、型腔尺寸、分流道及最小壁厚考慮設(shè)計(jì)推桿如下:圖68.2 復(fù)位桿設(shè)計(jì)推出機(jī)構(gòu)在注射模工作時(shí),每開合模一次,就往復(fù)運(yùn)動(dòng)一次,除了推桿和復(fù)位桿與模板的活動(dòng)配合以外,其余均處與浮動(dòng)狀態(tài),使推出機(jī)構(gòu)復(fù)位最簡(jiǎn)單最常用的方法是在推桿固定板同時(shí)安裝復(fù)位桿,復(fù)位桿為圓形截面,每副模具一般設(shè)置4根根據(jù)模架的選擇,復(fù)位桿設(shè)計(jì)如下:圖7數(shù)量為4根,中心距為14650mm,此外由于設(shè)置側(cè)向抽芯的緣故,為了防止干涉需要在復(fù)位桿設(shè)置彈簧,彈簧先復(fù)位機(jī)構(gòu)是利用彈簧的彈力使推出機(jī)構(gòu)在合模之前進(jìn)行復(fù)位的一種先復(fù)位機(jī)構(gòu),即彈簧被壓縮地安裝在推板固定板與動(dòng)模支承板之間。為了使復(fù)位桿能夠及時(shí)復(fù)位,設(shè)計(jì)彈簧中徑為14mm, 截面直徑為3mm。9.確定注塑機(jī)型號(hào)9.1 注塑機(jī)的選擇 1)初選注射機(jī)注射量:該塑料制件的單件重量Ms 1.78g澆注系統(tǒng)重量的計(jì)算,根據(jù)澆注系統(tǒng)尺寸先計(jì)算澆注系統(tǒng)的體積 Vj= 20+1407.95+10302527.95 cm3粗略計(jì)算澆注系統(tǒng)重量Mj=Vj30 g總體積 V塑件=934.56+2527.95 = 3.3925 cm3總質(zhì)量 M= 3.39251.0536 gABS的密度為 1.031.05g/ cm3。滿足注射量:V機(jī)V塑件/0.80式中 V機(jī)額定注射(cm3)V塑件-塑件與澆注系統(tǒng)凝料體積和(cm3)V機(jī)= V塑件/0.8 4.3 cm3或滿足注射量M機(jī)M塑件/0.8M機(jī)= M塑件/0.8=4.5g注射壓力P注P成型查表得ABS塑料成型時(shí)的注射壓力P成型=7090Mpa.鎖模力:P鎖模力PF式中P塑料成型時(shí)型腔壓力ABS塑料的型腔壓力P=30MpaF澆注系統(tǒng)和塑件在分型面上的投影面積和分型腔及澆住引流及型腔在分型面上的投影面積F= 830(3.145.15.1- 3.141.71.7)+30(1010+3.1455) =79298.2 PF= 3079298.2 = 2378946N23.79KN根據(jù)以上分析與計(jì)算.查表得初選注射機(jī)的型號(hào)為:XS-Z-30注射機(jī)XS-Z-30有關(guān)技術(shù)參數(shù)如下:最大開合模行程 160 mm模具最大厚度 180 mm模具最小厚度 60 mm噴嘴圓弧半徑 12mm噴嘴孔直徑 2 mm動(dòng)、定模板尺寸 250 mm 280 mm拉桿空間 235 mm2)選標(biāo)準(zhǔn)模架A3 根據(jù)以上分析計(jì)算型腔尺寸及位置尺寸可確定模架的結(jié)構(gòu)形式和規(guī)格。選用A3型模架 GB/T 12556.1-1990動(dòng)模板厚A=40mm推件板厚度=16mm固定板厚度B=32墊塊厚度C=63模具厚度:H模=40+A+B+C+32=191mm模具外形尺寸:160160191mm3)校核注射機(jī)注射量、鎖模力、注射壓力、模具厚度的校核 由于在初選注射機(jī)和標(biāo)準(zhǔn)模架時(shí)是根據(jù)以上四個(gè)技術(shù)參數(shù)及計(jì)算壁厚等因素選用的,所以注射量、鎖模力、注射壓力、模具厚度不必進(jìn)行校核,已符合所選注射機(jī)要求。9.2 開模行程的校核注射機(jī)最大行程S S2h件+h澆+(510)式中h件-塑料制品高度(mm);h澆-澆注系統(tǒng)高度(mm)。 2h件+h澆+(510)=218.41+74+8=118.82mm故滿足要求。9.3 模具在注塑機(jī)上的安裝從標(biāo)準(zhǔn)模架外形尺寸看小于注射機(jī)拉桿空間,并采用壓板固定模具,所以選注射機(jī)規(guī)格滿足要求。10.模具總裝圖圖81-動(dòng)模座板 2-墊塊 3-內(nèi)角螺釘 4-支承板 5-型芯固定板 6-定模座板 7-內(nèi)角螺釘8-澆口 9-導(dǎo)套 10-定模板 11-導(dǎo)柱 12-拉料桿 13-推桿 14-推桿固定板15-推板 16-復(fù)位桿11致 謝致謝通過這一個(gè)月來的設(shè)計(jì),不僅是對(duì)我3年來學(xué)習(xí)的總結(jié)和回顧,同時(shí)也讓我深深的明白了自身的諸多不足之處,這也是今后在社會(huì)上學(xué)習(xí)的一種動(dòng)力,我將會(huì)不斷地學(xué)習(xí)、不斷地充實(shí)自己。由于時(shí)間和自身能力有限,設(shè)計(jì)難免會(huì)存在著不足之處,懇請(qǐng)各位老師給予指正。至此,感謝學(xué)校,感謝老師在這3年里對(duì)我的諄諄教導(dǎo),讓我充實(shí)的度過了這3年的大學(xué)生活,你們的教誨將是我最寶貴的財(cái)富。最后,感謝我的指導(dǎo)老師對(duì)我設(shè)計(jì)的悉心指導(dǎo)和耐心幫教。12附 錄參考文獻(xiàn)1 塑料成型工藝與模具設(shè)計(jì).屈華昌主編塑料成型工藝與模具設(shè)計(jì).北京:機(jī)械工業(yè)出版社,1996.42 馮炳堯韓泰榮蔣文森 編 丁戰(zhàn)生審. 模具設(shè)計(jì)與制造簡(jiǎn)明手冊(cè) .上海:上??茖W(xué)技術(shù)出版社,1998.73 唐志玉主編. 塑料模具設(shè)計(jì)師指南.北京:國防工業(yè)出版社,1999.64 馮炳堯 韓泰榮 蔣文森主編. 模具設(shè)計(jì)與制造簡(jiǎn)明手冊(cè)第二版.上海:上海科學(xué)技術(shù)出版社,19945 王桂萍邱以云主編. 塑料模具的設(shè)計(jì)與制造問答.北京.機(jī)械工業(yè)出版社6 奚永生主編.精密注射模具設(shè)計(jì).北京.中國輕工業(yè)出版社7 陸寧主編.實(shí)用注射模設(shè)計(jì).北京.中國輕工業(yè)出版社,1997.58 宋玉恒主編. 塑料注射模機(jī)構(gòu)與結(jié)構(gòu)設(shè)計(jì).北京.航空工業(yè)塑料模具編制組,1986.99 中國機(jī)械工業(yè)教育協(xié)會(huì)組編.注射模設(shè)計(jì)及制造.北京.中國機(jī)械工業(yè)教育協(xié)會(huì),2001.810 蔣繼宏王效岳主編. 注射模典型結(jié)構(gòu)例.北京.中國輕工業(yè)出版社,2000.611 賈潤(rùn)禮程志遠(yuǎn)主編. 實(shí)用注射模設(shè)計(jì)手冊(cè).北京.中國輕工業(yè)出版社,2000.412 徐進(jìn)陳再枝等編. 模具材料應(yīng)用手冊(cè).北京.機(jī)械工業(yè)出版社,2001.713 廖念針等主編. 互換性與技術(shù)測(cè)量.北京.中國計(jì)量出版社,2000.113Optimization of Gate, Runner and Sprue in Two-Plate Family Plastic Injection Mould M.A. Amran * , M. Hadzley, S. Amri, R. Izamshah, A. Hassan, S. Samsi, and K. Shahir 1 Faculty of Manufacturing Engineering, Universiti Teknikal Malaysia (UTeM), Locked Bag 1200, Hang Tuah Jaya, Ayer Keroh, Melaka, Malaysia *Email: mohdamranutem.edu.my Abstract. This paper describes the optimization size of gate, runner and sprue in two-plate family plastic injection mould. An Electronic Cash Register (ECR) plastic product was used in this study, which there are three components in electronic cast register plastic product consist of top casing, bottom casing and paper holder. The objectives of this paper are to find out the optimum size of gate, runner and sprue, to locate the optimum layout of cavities and to recognize the defect problems due to the wrong size of gate, runner and sprue. Three types of software were used in this study, which Unigraphics software as CAD tool was used to design 3D modeling, Rhinoceros software as post processing tool was used to design gate, runner and sprue and Moldex software as simulation tool was used to analyze the plastic flow. As result, some modifications were made on size of feeding system and location of cavity to eliminate the short- shot, over filling and welding line problems in two-plate family plastic injection mould. Keywords: Computer Modeling; Flow Simulation; Optimization PACS: 07.05Tp 1. INTRODUCTION The plastic injection generally has three phase processes comprising filling, packing and cooling phases. The introduction of simulation software has made a significant impact in the mould making industry with the increasing use of computers in design engineering, the amount of commercially available software on the market has also increased 1. The ECR plastic product uses same material and colour, however different size of part. Each part has it own mould but on this research, all the parts used family mould. The difficult stage to design family mould is to decide the mould layout, injection location, size of gate, runner, sprue and location of water holes 2, 6, 7. To investigate the flow behaviour the Moldex software as simulation software was used to analyze the plastic flow. 2. METHODOLOGY This study started from design 3D modeling of ECR product using Unigraphic software and then the files were transferred into Rhinoceros software for post processing. In Rhinoceros software the feeding system such as gates, runners, sprues, 309 waterholes and mould base were designed. Finally, Moldex software is used by importing file from Rhinoceros software. Plastic materials, processing conditions were decided before filling, packing, cooling and warpage analysis. If results do not satisfy, the modification will be done again as shown in Figure 1. End Interperet data A is surface area of cavity (mm 2 ) and n is material constant. From calculation surface area of top casing is 84,648 mm 2 , the width is 5.8 mm. Further calculation, bottom casing width is 5.9 mm and paper holder is 1.27 mm. 3.2 Circular Runner Diameter runner was calculated by taking the weight of part from volume multiply density and distance part from centre of mould as equation 2 4. D = W x L / 30 (2) Where, D is runner diameter, W is part weight and L is distance part to centre mould. Volume of top casing was taken from Rhinoceros software is 78,202 mm 3 and the weight is 0.08 kg so the diameter of runner is 6.5 mm. Further calculation, the diameter of bottom casing is 6.7 mm and paper holder is 1.5 mm. 3.3 Sprue The sprue size was decided by taking the thickness cavity plate mouldbase and given angle one degree from diameter 7 mm. Initial cold slug well is 7 mm and base cold slug well is 10 mm. Figure 3 shows the location of top casing, bottom casing and paper holder together with feeding system. FIGURE 3. Layout of two-plate mould. 311 4. FILLING ANALYSIS OF TWO PLATE MOULD Result from filling analysis shows that the total filling period is 1.041 seconds. At the stage, 100% there were two results where the top casing was short shot and the plastic cannot flow to the impression of paper holder as shown in Figure 4. FIGURE 4. Filling process The top casing was redesigned because of the meeting area of flow front situated at side body, as result a welding line was developed on that area as shown in Figure 5. Welding line is the result of a flow front, which easily breaks up into two separate parts. When the two fronts meet, they try to welding back together again so as result form a single front line which it can be easily broken down 5. FIGURE 5. Welding line at top casing 4.1 Modification on Two-Plate Mould Modification was done on gate of bottom casing by decreasing 25% from 5.9 mm to 4.3 mm and runner from 6.7 mm to 5 mm due to over filling. Location of paper holder was moved from 50 mm from center of mould to 25 mm and increase runner size by 25%. A set of groove was added on surface of top casing to ensure the plastic flow toward corner of top casing as shown in Figure 6. FIGURE 6. Modification of Two-Plate mould. 312 4.2 Filling process after Modification Result from filling analysis after modification shows the melt of plastic of three components were balance on each other. The total filling melt front time is 7.804x10 -1 seconds. The welding line has been eliminated on the centre side body of top casing and as result melt plastic flows towards on the corner as shown in Figure 7. FIGURE 7. Filling process after modification 5. DISCUSSION The size of runner of paper holder was increased and shifted to eliminate the unfilling. Gate and runner of bottom casing were decreased due to the over filling. Top casing was redesigned by adding a set of groove on the top surface of top casing to eliminate the welding line. As the result the welding line on centre side body of top casing was eliminated. From results it was found that the size of gate and runner in two-plate mould for paper holder increased by 25% due to the short shot problem and gate and runner for bottom casing reduced by 25% due to the over filling. 6. CONCLUSION This study was success on analyzing the flow of plastic materials in two-plate mould. The modifications was done on layout of cavities and feeding system as result improved the quality of the product. Furthermore, the defects of plastic product on short shot, over filling and welding line were eliminated before the actual mould is fabricated. REFERENCES 1. S.S.S. Imehezri., S.M. Sapuan, S. Sulaiman, Journal Material and Design, volume 26, pp. 157 166, 2005. 2. L.T. Manzione, Applications of Computer Aided Engineering in Injection Molding, Hanser, New York, 1987. 3. R.G.W. Pye, Injection Moulding Design, Longman Scientific & Technical, New York, 1989. 4. G. Monges & P. Mohren, How to Make Injection Molds, Hanser Publishers, New York, 1993. 5. M.B. Douglas, Plastics Injection Moulding- Manufacturing Process Fundamentals. Society of Manufacturing Engineer, Michigan, 1996. 6. C.T. Wong, S. Sulaiman , N. Ismail, A.M.S. Hamouda, Procedings of Second World Engineering Congress, Sarawak, Malaysia,. pp. 193-198, 2002. 7. M. Khairol, Master Thesis, Universiti Putra Malaysia, 2001. 313 Copyright of AIP Conference Proceedings is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holders express written permission. 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