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[M].沈陽:遼寧科技技術(shù)出版社,2004廖念釗,莫雨松,李碩根,(第四版)北京:(第二版).武漢::Rapid Prototyping and manufacturingIntroduction The term “rapid prototyping” (RP) is a relatively new expression for the generation of threedimensional models manufactured without the need for machining or products designed on a puter aided design system, the first rapid prototyping system was introduced on to the US market in 1988 and gave the engineer the opportunity to produce 3 dimensional objects directly from Computer Aided Design (CAD) date and succeed in the costeffective production of patterns and moulds with plex surfaces.The principle advantages of using this technology are: n High speed at which the solid model is generated. n The plexity of the model does not form any limitation to its production. n The early use of these models was to assist the designer in determining fitness and form. It also provided the sales team with a 3 dimensional object to show to a prospective customer, this being far better than the traditional orthographic drawing which many people find difficult to interpret. n The benefits of RP: n Converts 3D CAD images into accurate physical models at a fraction of the cost of traditional methods. n Improves design munication and helps eliminate design mistakes. n Reduces “time to market” for a new product. n Can be used as a powerful marketing tool since the prototype can be seen rather than the drawing.The development of this technology has reached into many of the traditional fields, attracting the interest of artisans whose skill any knowledge has led to 3D objects being used directly and indirectly as patterns and model for soft tooling.Production of models by machining has a number of limitations. l Material removed during forming is difficult to reclaim. l Machining in the form of drilling turning milling spark erosion etc., is limited by the shapes it can produce. l In the event of design change, conventional tooling such as patterns ,core boxes, dies, jigs etc. ,bee expensive to alter ,and in many cases, may require plete remanufacture.Rapid prototyping differs with conventional manufacturing methods by adding material layer by layer until the desired sharp is achieved, immediately reducing or avoiding the loss of material.What RPamp。用機器制造以鉆井轉(zhuǎn)動的碾碎的火花電蝕等的形式。公司, 3D系統(tǒng)GmbH,開發(fā)了機器和軟件,一起允許模型以蜂窩的形式被修建。 通過提供一個物理產(chǎn)品在更加初期的設(shè)計,我們可以加速處理計劃和鑿出的裝飾設(shè)計??焖俪尚秃椭圃炷軌蚩焖俚纳a(chǎn)不用堅固的工具和人工成本。這簡化3D部分生產(chǎn)過程到增加過程的第2層數(shù),以便零件可以直接地由它的計算機模型生產(chǎn)。 3 對于新的產(chǎn)品減短上市的時間。,學(xué)會運用標(biāo)準(zhǔn)、規(guī)范、手冊和查閱相關(guān)資料的本領(lǐng)。定模型腔塊和定模板之間的間隙配合及動模型芯拼塊和推件塊之間的間隙配合為H7/m6,保證塑件不溢料。取型腔壓力為50 MPa, A=402+890=5744㎜2,則p腔A =505744103KN=,所選注塑機鎖模力為1300KN,足以滿足條件。冷卻介質(zhì)管道長度L為: L=A/πd=1010 m = m 。所以在設(shè)計型腔結(jié)構(gòu)和澆注系統(tǒng)時,必須注意排氣。額定轉(zhuǎn)矩298 NBM型擺線液壓馬達(dá)(以下簡稱馬達(dá))是一種內(nèi)嚙合擺線齒輪式的小型、低速、大扭矩液壓馬達(dá),其結(jié)構(gòu)簡單、低速性能好、短期超載能力強。導(dǎo)柱長度應(yīng)保證,開模后導(dǎo)柱的長度比凸模端面長出68mm,導(dǎo)柱數(shù)量為4個,帶肩導(dǎo)套和直導(dǎo)套各四個,:a 導(dǎo)柱b 導(dǎo)套 導(dǎo)柱與導(dǎo)套結(jié)構(gòu)圖 脫模機構(gòu)設(shè)計脫模機構(gòu)的設(shè)計必須達(dá)到以下要求:(1)使制品脫模后不致變形;(2)盡量不損傷制品的外觀;(3)脫模機構(gòu)應(yīng)動作可靠,運動靈活,制造方便,配換容易。螺距尺寸計算按下式計算:P=(1+Q)P0177。成型零部件的磨損主要來自塑料熔體流動時對它產(chǎn)生的沖擊和摩擦,以及制品脫模時對它的刮磨,尤其是刮磨影響最大。其中型腔尺寸又可分為深度尺寸和徑向尺寸,型芯尺寸又可分為高度尺寸和徑向尺寸。PP在注射壓力70MPa下的流動比L/T范圍為200~240。注射機安裝模板的大小。120H7 ㎜;料筒加熱功率:11KW;液壓泵電動機功率:22KW;重量:。㎜,㎜,㎜,因此,對成型條件和模具的設(shè)計提出較高的要求。該產(chǎn)品一體成型設(shè)計,外型優(yōu)雅美觀,設(shè)計精巧;管路和電源全部內(nèi)置,安全保潔,: 純水機組裝圖、尺寸精度和表面質(zhì)量分析結(jié)構(gòu)分析:該零件的總體形狀為圓蓋形,圓周外側(cè)有十二個止轉(zhuǎn)凸紋條,設(shè)計脫模機構(gòu)時可以利用它來起部分止轉(zhuǎn)作用。密度(g/㎝3)~預(yù)熱溫度(℃)80~100時間(h)1~2料筒溫度(℃)后段160~180中段180~200前段200~220模具溫度(℃)80~90噴嘴溫度(℃)170~190注射壓力(MPa)70~100成形時間(s)注射時間20~60高壓時間0~3冷卻時間20~90總 周 期50~160螺桿轉(zhuǎn)速(r/min)48估算塑件的體積和質(zhì)量:估算塑件的體積和質(zhì)量是作為確定型腔數(shù)目及選用注塑機的參考。 分型面位置 型腔布局設(shè)計型腔布局時應(yīng)滿足以下基本要求:型腔應(yīng)在相同溫度下同時充填;型腔流程短,以降低廢料;各型腔間距應(yīng)盡可能大,以便在空間設(shè)置冷卻水道、推桿,并具有足夠的面積,以承受注射壓力;型腔的布置和澆口的開設(shè)部位應(yīng)力求對稱,反作用力應(yīng)作用于注射機模板中心,以防模具承受偏載而產(chǎn)生溢料現(xiàn)象。在注射間隔時間,噴嘴端部的冷料必須去除,防止注入型腔影響塑料制品的質(zhì)量,故設(shè)計時應(yīng)考慮儲存冷料的措施。一般用鑲嵌形式比較好,尤其多腔模必須用鑲嵌形式,但要注意凹模的材料選用及型腔內(nèi)部,不允許有尖角部位,~,同時還必須考慮擠壓方法的不同對凹模的結(jié)構(gòu)形式和尺寸精度的影響。(3)制品和模具上的中心距尺寸均采用雙向等值正、負(fù)偏差,基本尺寸均為平均值。這種方法比較適用于成型物料來料量及制品生產(chǎn)批量都很大的場合。型腔深度尺寸計算:極限尺寸法:按修模時凹模尺寸減小容易設(shè)計,計算公式如下:H=[(1+Qmin)HSδ]其中: H—— 型腔深度最大尺寸;HS —— 制品高度尺寸;Qmin—— 塑件最小收縮率;其余符號同上。 h —— 螺紋型苡是螺紋工作高度,h=㎜; —— 螺紋升角,=ɑrctg np/πd= ;其余符號同上。當(dāng)P固定的時候,w與T是成反比的。 BM型擺線液壓馬達(dá) 二次脫模輔助機構(gòu)設(shè)計拉緊螺釘數(shù)量:4個,。所以塑料傳給模具的熱量Q=606016010600/3=115200kj。冷卻水孔管路一般最好不要開設(shè)在型腔塑料熔接的地方,以免影響制品強度;。 。試模時調(diào)節(jié)拉緊機構(gòu)27,保證定模板19與推件板53先分型;調(diào)節(jié)定距拉桿10的位置,保證第二次分型時分型面分開的距離不小于30mm,也不能大于38mm;調(diào)節(jié)觸動螺釘47的位置,保證從動輪帶動螺紋型芯11旋轉(zhuǎn)5圈后觸動回位確認(rèn)開關(guān)后停止旋轉(zhuǎn)。M CAN DO? To substantially shorten the time for developing patterns, moulds, and prototypes, some manufacturing enterprises have started to use rapid prototyping methods for plex patterns making and ponent prototyping. Over the past few years, a variety of new rapid manufacturing technologies, generally called Rapid Prototyping and Manufacturing(RPamp。 由它可能導(dǎo)致的形狀限制。 蜂窩結(jié)構(gòu)在本身崩潰在“燃燒的”因而避免擴展的問題。 另外,通過準(zhǔn)確描述復(fù)雜幾何,原型在解釋方案可能幫助減少問題在車間上。(2) 證明和優(yōu)化 改進(jìn)產(chǎn)品質(zhì)量總是制造業(yè)的一個重要問題。 原型零件是通過增加材料而不是除去材料導(dǎo)致的。 2 改進(jìn)設(shè)計的訊息幫助刪除設(shè)計的錯誤。,對塑料注射模有了一個全面的認(rèn)識,培養(yǎng)了正確的設(shè)計思路和分析解決問題的能力,同時提升了運用知識和實際動手的能力。,當(dāng)螺紋型芯11旋轉(zhuǎn)5周后,在推件板53和重力的作用下,塑件能自動脫落。 ,其關(guān)系按下式校核:p腔A ≤ P鎖式中 p腔 —— 模具型腔壓力,一般取40~50MPa;