【正文】
?。?) 創(chuàng)建模具元件的體積塊 利用分型面將工件拆分成型腔、型芯體積塊。在此,由衷的感謝我院系領(lǐng)導(dǎo)在畢業(yè)設(shè)計(jì)中對(duì)我們的指導(dǎo)與幫助,感謝四年來無私的傳授我們知識(shí)的老師們,因?yàn)樗麄兊母冻觯庞辛宋覀兊慕裉?,在這里,衷心的感謝老師的幫助,讓我的大學(xué)生涯畫上了完美的句點(diǎn)。 本章小結(jié)這章的設(shè)計(jì)內(nèi)容主要是側(cè)向分型機(jī)構(gòu),設(shè)計(jì)內(nèi)容包括,斜導(dǎo)柱、斜滑塊和滑塊限位機(jī)構(gòu)等。在核心的情況下簡單和容易的處理,也有將滑塊和核心為一體,稱為積分滑塊。斜導(dǎo)柱I:A1=4ⅹ20=80mm ,h=20mm ,p=12MPa ,μ=斜導(dǎo)柱II: h2=23mm斜導(dǎo)柱III: A1=ⅹ32= ,h=32mm (2)抽芯距S的計(jì)算 抽芯距指的是把側(cè)型芯從成型位置移動(dòng)到不阻礙脫模的位置的距離。所以有對(duì)模具進(jìn)行剛度和強(qiáng)度的校核是極其重要的,可以從根本上避免塑件缺陷的產(chǎn)生。第6章 成型零部件的設(shè)計(jì) 凹模的結(jié)構(gòu)設(shè)計(jì)凹模是用于成型塑件的外表面,一般可以分為整體式、整體嵌入式、瓣合式鑲拼組合式四種。 脫模機(jī)構(gòu)的設(shè)計(jì)原則脫模機(jī)構(gòu)種類雖然很多,但是具有相同的設(shè)計(jì)原則 ,具體設(shè)計(jì)原則有以下幾點(diǎn):(1)注射機(jī)的推出機(jī)構(gòu)帶動(dòng)脫模機(jī)構(gòu)的運(yùn)動(dòng),所以通常把脫模機(jī)構(gòu)設(shè)置在動(dòng)模一側(cè);(2)確保在推出的過程中塑件不發(fā)生;(3)確保在開模的過程中,塑件隨著動(dòng)模移動(dòng);(4)盡量設(shè)計(jì)的簡單可靠,有適合的推出距離,減少設(shè)計(jì)成本;(5)如果需要把塑件留在定模內(nèi),那么需要把脫模機(jī)構(gòu)設(shè)置在定模一側(cè)。第5章 導(dǎo)向與脫模機(jī)構(gòu)設(shè)計(jì)的設(shè)計(jì) 導(dǎo)柱與導(dǎo)套的設(shè)計(jì)注射模導(dǎo)向機(jī)構(gòu)的作用是保證動(dòng)模和定模兩大部分之間的準(zhǔn)確配合以及可靠的分開,能夠避免產(chǎn)生由于內(nèi)部零件的碰撞和干涉導(dǎo)致的模具損壞。澆口在設(shè)計(jì)時(shí)應(yīng)該滿足熔融狀態(tài)下的物料快速充滿型腔,減小熱量,距離,壓力的損失,利于排氣,便于成型。(2) 圖 41中B 如果作為分型面,上下模腔加工簡單。然后校核注射機(jī)是否符合生產(chǎn),確定下注射機(jī)以后就可以確定一些成型的工藝參數(shù)。cm)~屈服強(qiáng)度/MPa50比體積/(cm微型化的發(fā)展方面。通過對(duì)模具的具體設(shè)計(jì)達(dá)到塑件的質(zhì)量和加工工藝要求。注射成型的特點(diǎn)有:成型周期短、工藝適應(yīng)性強(qiáng)、生產(chǎn)效率高。ABS為熱塑性塑料,抗拉強(qiáng)度30~50MPa,抗彎強(qiáng)度41~79MPa,拉伸彈性模量1587~2277MPa,彎曲彈性模量1380~2690MPa,~,%~%。 最大注射壓力的校核注射機(jī)的額定注射壓力必須大于或等于塑件成型所需要的注射壓力,即: ≥ (33)式中:——注射機(jī)的最大注射壓力(MPa); ——塑料件成型時(shí)所需的注射壓力。另外還應(yīng)考慮到塑件的表面外觀質(zhì)量要求、尺寸精度、模具加工難易程度等因素。其功能是使塑料的熔融體加快流速從而注入型腔內(nèi),并有序的充滿型腔。澆口襯套如圖 44。導(dǎo)柱與導(dǎo)套之間的配合為H7/f6。脫模機(jī)構(gòu)一般都需要設(shè)計(jì)復(fù)位機(jī)構(gòu),除了推件板推出機(jī)構(gòu)。收縮率的確定方法和原則有以下幾種:(1)通常情況下,如果塑料的收縮率范圍較小,則選取平均收縮率。型腔壁厚的設(shè)計(jì),可以保證模具在工作過程中的安全性和可靠性,避免在工作過程中產(chǎn)生不必要的意外,而影響塑件的質(zhì)量。(4)斜導(dǎo)柱直徑的確定根據(jù)公式: (72)式中:d——斜導(dǎo)柱直徑(mm); FC——抽芯力(N ——斜導(dǎo)柱所用材料的許用應(yīng)力,一般碳鋼可取 HW——側(cè)型芯滑塊受到脫模力的作用線與斜導(dǎo)柱中心線交點(diǎn)到斜導(dǎo)柱固定板的距離,它的大小視模具結(jié)構(gòu)而定,并不一定等于滑塊高度的一半。圖 73楔緊塊的結(jié)構(gòu)形式楔緊塊的各種結(jié)構(gòu)形式如圖 73所示。(2)三通模具采用四向抽芯,最開始設(shè)計(jì)時(shí)選用六個(gè)個(gè)等長的型芯相接,但由于考慮的型芯間接觸是尖銳的平面,接觸時(shí)易磨損,后選用圓弧面的接觸方式,型芯根據(jù)塑件本體尺寸采用不同長度的的型芯進(jìn)行對(duì)接,用二長一短的斜導(dǎo)柱來配合型芯的運(yùn)動(dòng)。然后將原設(shè)計(jì)模型裝配至模具模綱中,使之成為模具設(shè)計(jì)的參照模型。附錄IIWith the continuous development of puter technology, mould gradually popularization, the digital design and manufacturing technology international appeared a variety of CAD/CAM software, and each has its own characteristics. Pro/Engineet (hereinafter referred to as Pro/E) is a parameter technology panies in the United States (PTC) launched a new generation based on the characteristics, with all the relevant database parameterized CAD/CAM software, can use it to part design, assembly, mold design, analysis and calculation, dynamic simulation, etc. Modelling ability strong, good patibility, and therefore is widely used in mould industry.(1) mould design based on Pro/EngineerOpposition HuoBan one of Pro/Engineer Pro/MoldDesign module, the module is a Pro/Engineer of mold design and analysis module, using the module, the designer can be a quick and efficient finish all kinds of mold design and analysis work. Below is the use of Pro/MoldDesigs design mould general process.(2) the original design modelThe mold design must establish a design model, namely mould manufacturing prototype, design model need to be done in Pro/Engineer part module 3 d modelling, usually by stretching, excision, draft, rounded corners, pump shell modeling method to create.(3) create a model of the mouldCreate mold model, selecting the file type, subtype choose mold cavity. And then to mold die assembly outline in the original design model, making it the reference model of mould design. Add has designed artifacts or using Pro/Moldesign tool automatically created in the mold, here the workpiece can be understood as a mould of billet.(4) the analysis modelUsing Pro/Engineer analysis function analysis model of the draft Angle, thickness, geometric characteristics, such as to determine whether these features meet the design requirements. If does not conform to, should be changed accordingly.(5) setting shrinkage rateDue to the changes of temperature and pressure, the casting from the mold after will produce contraction phenomenon, in order to pensate the deviation of volume contraction of castings, the Pro/Engineer provides shrinkage fun