電腦顯示器底座注射模具設(shè)計(jì)及分析【含CAD圖紙+文檔】
壓縮包內(nèi)含有CAD圖紙和說明書,均可直接下載獲得文件,所見所得,電腦查看更方便。Q 197216396 或 11970985
任 務(wù) 書院(系): 專業(yè): 班 級(jí): 學(xué)生: 學(xué)號(hào): 一、畢業(yè)論文課題電腦顯示器底座注射模具設(shè)計(jì)及分析二、畢業(yè)論文工作自 20xx 年 3 月 12 日起至 20xx 年 6 月 15 日止三、畢業(yè)設(shè)計(jì)進(jìn)行地點(diǎn) 廣東石油化工學(xué)院 四、畢業(yè)設(shè)計(jì)的內(nèi)容要求(一) 計(jì)算內(nèi)容與方案確定: (1)塑料制品外觀、結(jié)構(gòu)設(shè)計(jì)及材料選擇;(2)成型模具的結(jié)構(gòu)形式及注塑機(jī)選擇;(3)成型零件結(jié)構(gòu)設(shè)計(jì):動(dòng)、定模型腔尺寸的計(jì)算和布置;(4)結(jié)構(gòu)系統(tǒng)設(shè)計(jì)計(jì)算:頂出機(jī)構(gòu)、抽芯機(jī)構(gòu)、加熱、冷卻、澆注、排氣系統(tǒng)等尺寸 的計(jì)算與布置。 (5)強(qiáng)度設(shè)計(jì)和結(jié)構(gòu)草圖設(shè)計(jì):各部件的強(qiáng)度校核。(二) 設(shè)計(jì)內(nèi)容: 1、Pro/E環(huán)境下進(jìn)行產(chǎn)品(電腦顯示器底座)的三維建模;2、Pro/E環(huán)境下進(jìn)行產(chǎn)品塑件(電腦顯示器底座)的三維造型設(shè)計(jì);3、注射模裝配圖(1#或0#計(jì)算機(jī)圖);各主要零件的零件圖(1#、2#或3#計(jì)算機(jī)圖)。4、編寫設(shè)計(jì)(論文)說明書(不少于1.5萬字,全部用計(jì)算機(jī)輸出)。 (三) 外文資料翻譯檢索與閱讀與設(shè)計(jì)題目相關(guān)的外文資料,并書面翻譯(并不少于0.2萬字)的外文資料。(四)進(jìn)度要求:1、設(shè)計(jì)進(jìn)度嚴(yán)格按進(jìn)度表要求,按時(shí)完成計(jì)劃設(shè)計(jì)工作;2、按時(shí)呈送指導(dǎo)老師檢查。(五)設(shè)計(jì)結(jié)束學(xué)生應(yīng)交的設(shè)計(jì)文件1、畢業(yè)設(shè)計(jì)說明書:15000字;2、外文翻譯:20005000字(附原文);3、設(shè)計(jì)圖紙折合2張零號(hào)圖; 4、設(shè)計(jì)中文摘要: 約300字。(六)主要參考資料 1、塑料注射模具設(shè)計(jì)實(shí)用手冊(cè),航空工業(yè)出版社。2、塑料模設(shè)計(jì)手冊(cè),機(jī)械工業(yè)出版社。3、塑料注射成型模具結(jié)構(gòu)圖冊(cè),上海市第二輕工協(xié)會(huì)。4、典型注射模具結(jié)構(gòu)圖冊(cè),中南工業(yè)大學(xué)出版社。5、注塑模具設(shè)計(jì)要點(diǎn)與圖例,化學(xué)工業(yè)出版社。6、模具CAD/CAM技術(shù)應(yīng)用,機(jī)械工業(yè)出版社。7、阮鋒等,Pro/ENGINEER2001模具設(shè)計(jì)與制造實(shí)用教程,機(jī)械工業(yè)出版社。8、Pro/ENGINEER Wildfire模具設(shè)計(jì)實(shí)例教程精解,機(jī)械工業(yè)出版社。9、實(shí)戰(zhàn)Pro/ENGINEER2001模具設(shè)計(jì),中國(guó)鐵道出版社。10、何滿才,模具設(shè)計(jì)與加工MasterCAM9.0實(shí)例詳解M,人民郵電出版社。11、注塑模具典型結(jié)構(gòu)100例,中國(guó)輕工業(yè)出版社。12、機(jī)械制造工藝師手冊(cè). 機(jī)械工業(yè)出版社。指導(dǎo)教師 接受論文任務(wù)開始執(zhí)行日期 20xx 年 3 月 12 日學(xué)生簽名 Injecting Design Into the Molding Process There are a number of factors medical device manufacturers need to consider when using injection molded parts in their device, If they dont, they may he caught by surprise when they think they are ready to move into full production on a part. This article reviews the potential concerns that must he addressed early in the design process. By Nicole Hamilton Bernheimer and Philip BlyskalMedical device companies are always under pressure in two key areas: time and cost.Time delays in the production cycle can substantially affect product introduction timetables, and consequently, revenue. One area where medical device companies often lose valuable time, experience cost overruns, and face production delays is in poor design of injection molded components related to the mechanical functioning of the mold.Illustration of an injection molding systemInjection mold fabrication is widely used in medical device manufacturing because of its versatility.Many different types of plastics can once a mold is made, an extremely large number of pieces can be manufactured with it. Because of this,injection molding manufacturing is extremely cost effective in high volume production. But the properties of injection molding (plastic resin is fed into the injection machine, heated, and forced at high pressure into the mold by a screw and cures on cooling), and the mechanics of molding, dictate that designers pay particular attention to certain principals to ensure successful manufacture. Often medical device designers know basic injection mold design rules but this may not be enough to ensure smooth manufacture of parts and guarantee that the mechanical functioning of the mold does not cause problems.Much of the specifics of mold design have to do with the particular characteristics of thermoplastics.Thermoplastics are heated, melted,and then injected at high pressure into the mold. They cure upon cooling and parts shrink during this cooling time. The variation in shrinkage that can occur must be a major consideration for a designer in order to achieve dimension control, hold tolerances, and avoid warpage. This shrinkage is due to a number of variables : The type of plastic used The rate of cooling in the mold The wall section dimensions The gate location and the related flow characteristics in the mold The molding machine process parameters (such as temperature and pressure)Product designers often know the basic design rules relating to the variation in shrinkage rates for plastic parts and design accordingly.They desigh parts and assemblies with the achievable tolerances in mind and plan for steel safe construction in the mold as a means of revision to achieve the required dimensions.However, the reason that many molds see significant delays in achieving a production process is often overlooked by the product designer. These problems relate to the mold construction and how it functions. Specifically, there are three main areas of concern : Parting lines (where the mold opens) The type and location of gate(s)(opening through which plastic is forced into the part) How the part is ejected from the moldAll three of these mold design and construction features have a direct relationship to each other and to the overall look and quality of the molded part.The product designer must have an intimate knowledge of mold design and construction techniques or must use the services of a manufacturing engineer early in the design cycle in order to avoid costly and time consuming pitfalls. Altering the mold to achieve the required dimensions can be difficult at times but is generally able to be accomplished. If a major mistake occurs with any of the three areas listed above, it is possible that the mold might need major revision or to be built over again. This can result in tens of thousands of dollars,sometimes hundreds of thousands of dollars, wasted in redoing molds, in addition to revenue lost from production delays. Keeping the following issues in mind is crucial to successful medical product manufacture. Parting LinesParting lines directly affect the draft angles that are required on a part and the resulting dimensional changes. Draft angles must result in a proper slope so that the piece can eject properly and remain on the stationary side of the mold. As plastics cool, it adheres to the sides of the metal mold which can make ejection difficult or even impossible if adequate draft angles are not included.Parting lines must also be considered when determining the basic functioning of the mold, but are also very important to the cosmetics of the molded product. Parting lines will leave visible lines in the part that will obviously affect the visible surface after assembly. It may be unacceptable for certain parting line locations to appear on the exterior of a product, and design should be determined accordingly. GatingGate placement can play a big part on quality, appearance, and cycle time. It affects the flow characteristics of the plastics as it fills the mold, which is directly related to the shrinkage and the resulting part dimensions. It must also allow for adequate plastic flow distribution to ensure optimum form and strength of the part. Gate placement and type can dramatically affect cycle time for the process. Since manufacturing cost is directly related to cycle timethe faster the cycle, the lower the manufacturing costgating placement must ensure efficient and effective manufacture. Gates can also have a significant impact on the cosmetics of a part,creating a blemish where the plastic enters the part. On every part, there inevitably has to be a gate and therefore a gate mark so the placement must be strategic.A mold maker might decide to put a gate on a certain part of a mold for their convenience but this new location may be detrimental to the use of the part. Gate placement changes will affect the entire mold,which can mean much time and money wasted. Ejection A design defect that can create the biggest manufacturing problem is arguably when ejection doesnt work and/or potentially damages the part. Ejection problems (failure of the part to eject cleanly and completely from the mold without warpage or other damage) can cause significant delays in startup production and affect the cycle time for the process. Ejection also affects the cosmetics of the part due to the witness lines that arise from the use of ejector pins, etc. In some cases, ejection design problems can be fixed easier than moving the gates, but sometimes, it can affect other design issues and result in new molds being necessary. With certain parts, ejection can be more complicated and require activation from both sides of the mold. Avoid Mold Design PitfallsA designer who takes into account individual potential pitfalls can still err if the relationship between design factors is not considered since many design principals are interconnected. Gating, parting lines, and ejection are all related to each other, and a device manufacture may have used up their budget by the time they realize it, which is often at the point when they expect to go into full production. Designers often design the parts and take them to a manufacturing facility late in the game expecting production to go off without a hitch. In reality, manufacturing design should be included throughout the design process so that interactions can be taken into account in the earliest part of the design phase. Choose a manufacturing vendor or experienced consultant early on and have them do a detailed review of the interconnected factors that affect manufacture. Serious delays and expense can result from molds not working, and this can be avoided with careful planning and expertise. 成型工藝下的注射設(shè)計(jì)醫(yī)療設(shè)備制造商在他們的設(shè)備中使用的注塑件時(shí)需要考慮多項(xiàng)因素,如果他們不這樣做,當(dāng)他們認(rèn)為他們已經(jīng)準(zhǔn)備好并進(jìn)入全面生產(chǎn)時(shí)不考慮的因素可能令他們措手不及。本文綜述了潛在的擔(dān)憂,必須解決在設(shè)計(jì)過程的早期。尼科爾哈密爾頓伯恩海默和菲利普布雷??坚t(yī)療設(shè)備公司總是在兩個(gè)關(guān)鍵領(lǐng)域的壓力下:時(shí)間和成本。生產(chǎn)周期時(shí)間延遲也會(huì)影響產(chǎn)品介紹時(shí)間表和收益結(jié)果。一些領(lǐng)域的醫(yī)療設(shè)備公司在欠缺設(shè)計(jì)注塑件相關(guān)的模具機(jī)械功能的經(jīng)驗(yàn),以至于生產(chǎn)延誤而導(dǎo)致失去寶貴的時(shí)間,從而使成本超支。注塑模具系統(tǒng)圖注塑模具加工因其多功能性而廣泛應(yīng)用于醫(yī)療設(shè)備制造業(yè)。許多不同類型大批量制件可以由一個(gè)塑料模具一次生產(chǎn)它。正因?yàn)榇?,注塑生產(chǎn)在批量生產(chǎn)中是極具成本效益的。但特性注塑成型(塑料樹脂被送入成型機(jī),加熱,并迫使在高壓下由一個(gè)澆口進(jìn)入模具,冷卻定型)和力學(xué)的成型,要求設(shè)計(jì)師特別注意某些特性來確保成功制造。通常醫(yī)療設(shè)備的設(shè)計(jì)者知道基本的注塑模具設(shè)計(jì)規(guī)則,但是這可能不足以確保零件的制造和保證機(jī)械運(yùn)作的模具不會(huì)引起問題。大部分的細(xì)節(jié)的模具設(shè)計(jì)與熱塑性塑料特殊的特征。熱塑性塑料加熱,熔化,然后塑料在高壓下進(jìn)入模具。塑料在冷卻時(shí)間內(nèi)凝固冷卻和部分收縮。對(duì)于一個(gè)設(shè)計(jì)師來說為了實(shí)現(xiàn)規(guī)??刂啤⒖刂瞥叽缙?,并避免翹曲變形,收縮的變化的產(chǎn)生一定是主要考慮因素。而收縮是由于以下諸多因素影響的:使用塑料的類型模具的冷卻速率制件的壁厚澆口的位置和模具相關(guān)的流動(dòng)特性注射機(jī)工藝參數(shù)(如溫度、壓力)產(chǎn)品設(shè)計(jì)師常常知道基本的設(shè)計(jì)規(guī)則和收縮率相應(yīng)地有關(guān)的變化對(duì)塑料零件進(jìn)行設(shè)計(jì)。他們的設(shè)計(jì)與實(shí)現(xiàn)零部件及裝配公差在規(guī)定和標(biāo)準(zhǔn)在模具設(shè)計(jì)中作為一種修正值,并達(dá)到要求的配合度。然而,在模具的顯著效率下在實(shí)現(xiàn)生產(chǎn)過程中經(jīng)常被產(chǎn)品設(shè)計(jì)師忽視的理由。這些問題涉及到模具結(jié)構(gòu)和功能。具體來說,涉及到以下三個(gè)主要方面:分型面澆注位置和方式如何頂出制件這三個(gè)方面如何設(shè)計(jì)的在模具設(shè)計(jì)中直接關(guān)系到產(chǎn)品的整體外觀和質(zhì)量的好壞。所以產(chǎn)品設(shè)計(jì)師必須是一個(gè)非常熟悉模具設(shè)計(jì)和成型工藝的,如果在模具設(shè)計(jì)完成后再改變這三個(gè)方面的設(shè)計(jì),這會(huì)導(dǎo)致時(shí)間的浪費(fèi)和成本的提高,這會(huì)導(dǎo)致數(shù)萬美元,有時(shí)甚至數(shù)十萬美元浪費(fèi)在重作模具上。因此,設(shè)計(jì)師必須在設(shè)計(jì)周期之前就要著手解決以上所提到的三個(gè)問題。以下議題是保持醫(yī)療產(chǎn)品制造成功的關(guān)鍵。分型面在分型面的設(shè)計(jì)中,脫模斜度是最主要和最直接影響設(shè)計(jì)的因素,分型面必須有一定的脫模斜度,如果沒有一定的脫模斜度,在注塑完成后,開模時(shí)制件包緊在動(dòng)模一側(cè)就很難脫模甚至于不能脫模。分型面的位置也必須考慮在確定模具的基本運(yùn)作前,一些不正確的分型面在分模后可能會(huì)在制件的表面看的一條明顯的痕跡,在一些表面精度要求高的產(chǎn)品中,在外觀上出現(xiàn)這樣一個(gè)分模線可能是不可以接受的,在設(shè)計(jì)之前必須注意到這個(gè)問題。澆注位置和方式澆注位置和方式在制件質(zhì)量、外觀和周期時(shí)間上影響很大。它在塑料填充模具時(shí)影響的塑料的流動(dòng)特性,直接相關(guān)的收縮率,以及部分維度。它還必須充分考慮塑性流動(dòng)分布以確保最佳澆注形態(tài)和力學(xué)分布。澆注位置和類型可以極大地影響周期時(shí)間的過程。因?yàn)橹圃熘芷诘拈L(zhǎng)短直接影響生產(chǎn)成本,要降低制造費(fèi)用,澆注位置必須確保高效和有效。澆口在一些產(chǎn)品的生產(chǎn)中有很大的影響,創(chuàng)建一個(gè)點(diǎn)澆口將塑料注射到模具中。在每一個(gè)塑料制品中不可避免的會(huì)產(chǎn)生一個(gè)澆注時(shí)產(chǎn)生的澆口痕跡,因此在澆口的位置選擇上必須的合理的。模具制造商可能結(jié)合制件的使用條件而決定把模具的澆口位置設(shè)計(jì)在方便制件使用的位置上。然而澆口位置變化將影響到整個(gè)模具,這也意味著大量的時(shí)間和金錢浪費(fèi)了。頂出方式頂出裝置不能有效將制件頂出或者使制件在頂出是產(chǎn)生質(zhì)量問題是設(shè)計(jì)制造中的最大缺陷。頂出缺陷(在制件表面產(chǎn)生刮痕,或者使制件翹曲,壓裂等其他傷害)可導(dǎo)致影響周期的長(zhǎng)短和成本的提高。如果設(shè)計(jì)師使用頂針頂出的方式,頂出時(shí)也會(huì)影響制件表面有痕跡或其他缺陷。在某些情況下,在固定澆口中,設(shè)計(jì)頂出方式遇到的問題比移動(dòng)澆口簡(jiǎn)單得多。但有時(shí)候,它會(huì)影響其他的設(shè)計(jì)導(dǎo)致模具出現(xiàn)其他設(shè)計(jì)問題,頂出設(shè)置要求復(fù)雜還是靈活完全取決于模具。避免模具設(shè)計(jì)陷阱一個(gè)設(shè)計(jì)師考慮個(gè)人潛在誤區(qū)仍然可能犯錯(cuò)。如果設(shè)計(jì)的影響因素之間的關(guān)系并不被認(rèn)為是由于許多設(shè)計(jì)主體相互聯(lián)系的,澆注、分型面和頂出都是彼此相關(guān),當(dāng)他們意識(shí)到一個(gè)設(shè)備制造可能使用預(yù)算的時(shí)候,他們就清楚哪一個(gè)才算希望他們?nèi)ト嫔a(chǎn)的。設(shè)計(jì)師通常在設(shè)計(jì)一個(gè)產(chǎn)品后把它拿到生產(chǎn)制造處,希望生產(chǎn)制造處能用合適的工藝把產(chǎn)品順利的制造出來。然而在實(shí)際生產(chǎn)中,設(shè)計(jì)和制造應(yīng)該是一個(gè)整體的過程,在設(shè)計(jì)的早期就應(yīng)該選擇一個(gè)有豐富經(jīng)驗(yàn)的顧問的制造廠商,以便于互相交流,做一個(gè)詳細(xì)的設(shè)計(jì)制造方案,在仔細(xì)的規(guī)劃和專業(yè)知識(shí)下可以避免時(shí)間的浪費(fèi)和費(fèi)用的提高及模具的實(shí)用性。 學(xué)號(hào): 畢業(yè)設(shè)計(jì)說明書電腦顯示器底座注射模具設(shè)計(jì)及分析Computer monitors worldwide injection mold design and analysis學(xué)院 專業(yè) 班級(jí) 學(xué)生 指導(dǎo)教師(職稱) 完成時(shí)間 20xx 年 03 月 12 日至 20xx 年 06 月 15 日開題報(bào)告題目電腦顯示器底座注射模具設(shè)計(jì)及分析英文題目Computer monitors worldwide injection mold design and analysis學(xué)院 年級(jí)專業(yè)程學(xué)號(hào)姓名張 建 城指導(dǎo)教師鄧 宇 20xx年3月12日畢業(yè)設(shè)計(jì)開題報(bào)告題目電腦顯示器底座注射模具設(shè)計(jì)時(shí)間本課題的目的意義(含國(guó)內(nèi)外的研究現(xiàn)狀分析)我國(guó)塑料模具業(yè)發(fā)展相當(dāng)快,目前,塑料模具在整個(gè)模具行業(yè)中約占 80%左右,而在整個(gè)塑料模具市場(chǎng)中以注塑模具需求量最大。模具作為一種高附加值和技術(shù)密集型產(chǎn)品,其制造技術(shù)水平的高低,已經(jīng)是衡量一個(gè)國(guó)家制造業(yè)水平高低的重要標(biāo)志之一。而本題的設(shè)計(jì)將涉及一些二維軟件及三維軟件的應(yīng)用,如 AUTOCAD、PRO/E等,以及相關(guān)軟件的應(yīng)用。電腦顯示器底座注塑模具的 CAD 設(shè)計(jì)、分析, 包括根據(jù)產(chǎn)品模型進(jìn)行模具分型面的設(shè)計(jì)、 確定型腔和型芯、模具結(jié)構(gòu)的詳細(xì)設(shè)計(jì)、塑料充填過程分析等幾個(gè)方面。利用先進(jìn)的特征造型軟件PRO/E很容易地確定分型面, 生成上下模腔和模芯, 再進(jìn)行流道、澆口以及冷卻水管的布置等。通過對(duì)本課題的設(shè)計(jì),能夠提高理論分析能力與計(jì)算能力,同時(shí)提高分析問題和解決問題的能力,對(duì)我所學(xué)知識(shí)的鞏固及靈活運(yùn)用來解決實(shí)際問題有著深遠(yuǎn)的意義。設(shè)計(jì)(論文)的基本條件及設(shè)計(jì)(論文)依據(jù)(一) 設(shè)計(jì)之原始數(shù)據(jù):批量:50萬件/年獨(dú)立設(shè)計(jì)電腦顯示器底座,如圖所示,未注圓角R1,拔模斜度1。2、 設(shè)計(jì)依據(jù)1 王玉甲等. Pro/ENGINEER Wildfire 3.0模具設(shè)計(jì)完全自學(xué)手冊(cè).北京:機(jī)械工業(yè)出版社,2008.3.2 周四新. Pro/ENGINEER Wildfire 2.0工業(yè)設(shè)計(jì)從基礎(chǔ)到實(shí)踐.北京:電子工業(yè)出版社,2006.6.3 崔洪斌AUTOCAD 2008中文版實(shí)用教程北京:人民郵電出版社,2007.84 葉久新等. 塑料成型工藝及模具設(shè)計(jì).北京:機(jī)械工業(yè)出版社,2007.11.5 朱冬梅等畫法幾何及機(jī)械制圖.北京:高等教育出版社,2000.12.6 張榮清模具制造工藝北京:高等教育出版社,2006.1本課題的主要內(nèi)容、重點(diǎn)解決的問題主要內(nèi)容:設(shè)計(jì)方案:(1) 塑料成型工藝性分析;(2)擬定模具的結(jié)構(gòu)形式;(3)澆注系統(tǒng)的設(shè)計(jì);(4)成型零件的結(jié)構(gòu)設(shè)計(jì)及計(jì)算;(5)模架的確定;(6)排氣槽的設(shè)計(jì) ;(7)脫模推出機(jī)構(gòu)的設(shè)計(jì);(8)冷卻系統(tǒng)的設(shè)計(jì);(9)導(dǎo)向與定位結(jié)構(gòu)的設(shè)計(jì);(10)總裝配圖和零件圖的繪制。重點(diǎn)解決的問題:模具結(jié)構(gòu)型式的選擇,分型面的確定,脫模結(jié)構(gòu)的選擇,運(yùn)用Pro/E對(duì)模型進(jìn)行分析。本課題欲達(dá)到的目的或預(yù)期研究的結(jié)果通過這次的設(shè)計(jì),希望能使我更好的掌握本專業(yè)的專業(yè)知識(shí)和技術(shù),將理論知識(shí)與實(shí)際生產(chǎn)相結(jié)合,以及培養(yǎng)我分析問題和解決問題的能力,為提高模具設(shè)計(jì)質(zhì)量和效率而奮斗。計(jì) 劃 進(jìn) 度時(shí) 間工 作 內(nèi) 容備 注.3.10.3.20.3.21.3.31.4.1.4.10.4.11.4.25.4.26.5.11.5.12.5.25.5.26.6.9查閱有關(guān)模具設(shè)計(jì)資料,完成開題報(bào)告;查閱資料并完成外文翻譯;確定方案,畫出塑件圖;注塑模相關(guān)結(jié)構(gòu)設(shè)計(jì)及計(jì)算;畫出模具裝配圖和各零件圖;編寫設(shè)計(jì)說明書;修改畢業(yè)設(shè)計(jì)。指導(dǎo)教師意見 指導(dǎo)教師簽名: 年 月 日專業(yè)教研室意見 教研室主任簽名: 年 月 日文獻(xiàn)綜述學(xué)院(系) 專 業(yè) 班 級(jí) 姓 名 學(xué) 號(hào) 電腦顯示器底座注射模具設(shè)計(jì)及分析文獻(xiàn)綜述序言隨著消費(fèi)類塑料制品進(jìn)入千家萬戶,日常生活用具的塑料模具已經(jīng)占了很大比例。家電市場(chǎng)競(jìng)爭(zhēng)的白熱化,使電器外殼設(shè)計(jì)成為產(chǎn)品質(zhì)量的重要一環(huán),市場(chǎng)要求家電外殼的色彩、手感、精度、壁厚等都能夠時(shí)尚化,其中最為突出和典型的就是電腦。電腦在科技發(fā)達(dá)的今天作為家庭必不可少的產(chǎn)品,自然對(duì)外觀的要求很高。底座作為電腦顯示器的組成部分,在顯示器追求更小巧的今天,顯示器底座的外觀結(jié)構(gòu)自然成為研究對(duì)象。通過查閱各種文獻(xiàn),本文將對(duì)相關(guān)電腦顯示器設(shè)計(jì)、結(jié)構(gòu)、工藝進(jìn)行綜述,力求在做畢業(yè)論文時(shí)有個(gè)好的參考思路。注塑模具的發(fā)展注塑模具是生產(chǎn)各種工業(yè)產(chǎn)品的重要工藝裝備,隨著塑膠模具設(shè)計(jì)工業(yè)的迅速發(fā)展以及塑膠制品在航空、航太、電子、機(jī)械、船舶和汽車等工業(yè)部門的推廣應(yīng)用,產(chǎn)品對(duì)模具的要求越來越高,傳統(tǒng)的塑膠模具設(shè)計(jì)方法已無法適應(yīng)產(chǎn)品更新?lián)Q代和提高質(zhì)量的要求。注塑模具的前景在過去的20年中,我國(guó)模具工業(yè)得到了長(zhǎng)足的進(jìn)步。但是,我國(guó)的模具工業(yè)與模具發(fā)達(dá)國(guó)家相比,其差距表現(xiàn)在:模具的設(shè)計(jì)水平;模具的制造水平;模具的標(biāo)準(zhǔn)化水平。長(zhǎng)期以來,我國(guó)高聚物成型加工過程工藝參數(shù)的設(shè)定和模具設(shè)計(jì)與制造主要依賴于工藝人員和模具設(shè)計(jì)人員的經(jīng)驗(yàn)和技巧,設(shè)計(jì)的合理性只能通過試模來判斷,制造的缺陷也主要靠修模來糾正,導(dǎo)致模具及制品的設(shè)計(jì)與制造周期長(zhǎng)、成本高、檔次低。我國(guó)模具技術(shù)水平大約落后于國(guó)外20年,模具生產(chǎn)只能滿足需要的60%左右,每年進(jìn)口的精密復(fù)雜模具高達(dá)數(shù)億美元。所以,今后模具工業(yè)的發(fā)展趨勢(shì)是現(xiàn)代設(shè)計(jì)方法與工藝設(shè)計(jì)相結(jié)合,模具工業(yè)向著集團(tuán)化、規(guī)模化方向發(fā)展,完善模具設(shè)計(jì)的CAD/CAM/CAE一體化技術(shù)。在模具的開發(fā)和制造過程中,采用數(shù)控精密高效加工設(shè)備、采用逆向工程、并行工程、敏捷制造、虛擬技術(shù)等先進(jìn)制造技術(shù)?,F(xiàn)代模具制造技術(shù)的發(fā)展1、模具的標(biāo)準(zhǔn)化加快模具的標(biāo)準(zhǔn)化、商品化發(fā)展,適應(yīng)大規(guī)模成批生產(chǎn)的需要,可以提高模具的制造質(zhì)量、縮短模具的制造周期。2、新材料、新技術(shù)、新工藝的研究和應(yīng)用研究開發(fā)模具新材料,進(jìn)一步提高模具鋼材的耐磨、耐蝕、綜合機(jī)械性能、加工性能和拋光性能,是提高模具質(zhì)量的穩(wěn)定性和使用壽命的主要途徑和發(fā)展趨向。3、現(xiàn)代生產(chǎn)制造方式在完全實(shí)現(xiàn)模具標(biāo)準(zhǔn)件、通用件的生產(chǎn)專業(yè)化,供應(yīng)商品化的基礎(chǔ)上,利用現(xiàn)代IT技術(shù),組成局域通信網(wǎng)絡(luò),將計(jì)算機(jī)設(shè)計(jì)完成的各成型面、配合面數(shù)字化,并編成代碼直接輸入數(shù)控機(jī)床或CNC加工中心進(jìn)行自動(dòng)編程,繼而完成自動(dòng)加工。加工過程中能夠完成自動(dòng)檢測(cè)和結(jié)果的自動(dòng)顯示,從而實(shí)現(xiàn)產(chǎn)品設(shè)計(jì)、模具設(shè)計(jì)以及模具制造的自動(dòng)化和智能化并以此提高設(shè)計(jì)和制造的速度和質(zhì)量,減少人為的多層次失誤造成的缺陷,從而縮短模具生產(chǎn)周期,提高模具質(zhì)量以及使用的可靠性和壽命。4、塑料制件的精密化、微型化、超大型化為了滿足各種產(chǎn)品越來越高的使用要求,塑料模具和塑料成型技術(shù)正朝著精密化、微型化和超大型化方向發(fā)展。輔助設(shè)計(jì)制造的應(yīng)用隨著計(jì)算機(jī)的應(yīng)用發(fā)展,將其應(yīng)用于模具的設(shè)計(jì)與制造,已成為快速制造模具的有力保證。長(zhǎng)期以來,注射模成型工藝由于塑料制品的多樣性、復(fù)雜性和工程技術(shù)人員經(jīng)驗(yàn)的局限性,工程技術(shù)人員很難精確地設(shè)置制品最合理的加工參數(shù),選擇合適的塑料材料和確定最優(yōu)的工藝方案。在開始大規(guī)模生產(chǎn)前,由于僅憑經(jīng)驗(yàn)設(shè)計(jì)模具,模具裝配完畢后,通常需要幾次試模,發(fā)現(xiàn)問題后,不僅要工藝師重新設(shè)置工藝參數(shù),甚至還要設(shè)計(jì)師調(diào)整塑料制品和模具設(shè)計(jì)方案,修改模具。重復(fù)各個(gè)步驟增加了生產(chǎn)成本,影響模具質(zhì)量,同時(shí)延長(zhǎng)了制品生產(chǎn)時(shí)間。因此,用計(jì)算機(jī)進(jìn)行輔助設(shè)計(jì)制造,對(duì)模具的設(shè)計(jì)制造具有重要的作用。幾何造型運(yùn)用Pro/Engineer2000i對(duì)計(jì)算機(jī)顯示器底座進(jìn)行了三維實(shí)體造型,三維實(shí)體圖如圖1所示。制件長(zhǎng)度247mm,寬度200mm,高度34.1mm,最大壁厚為4.84037mm,最小壁厚為0.279156mm。澆口設(shè)計(jì)作為塑料流入模具型腔的入口,澆口位置的選擇直接影響到塑件外觀、質(zhì)量、力學(xué)性能的好壞。在澆口位置選擇是可以依據(jù)模流分析軟件進(jìn)行澆注分析,及時(shí)發(fā)現(xiàn)產(chǎn)品的內(nèi)在質(zhì)量問題,通過調(diào)整準(zhǔn)確的找準(zhǔn)澆口的位置。借助PRO/E的模流分析系統(tǒng)Plastic Advisor及根據(jù)產(chǎn)品的外觀質(zhì)量要求,防止?jié)部谠诋a(chǎn)品外形留下切除痕跡,所以將澆口設(shè)計(jì)在塑件內(nèi)表面的中心。通過分析,塑件注射過程中存在個(gè)邊位置不能充模與排氣不良的現(xiàn)象。根據(jù)出現(xiàn)的問題,對(duì)注射機(jī)的注射壓力、溫度等工藝參數(shù)進(jìn)行修改,得到滿足質(zhì)量要求的塑件。這樣既保證了塑件的尺寸、形狀要求,又不影響塑件的外觀質(zhì)量。它的優(yōu)點(diǎn)是通過借助PRO/E的模流分析系統(tǒng)Plastic Advisor對(duì)產(chǎn)品進(jìn)行澆口位置分析,找出合適的澆口位置,Plastic Advisor(塑料顧問)不但分析簡(jiǎn)單方便,免去了繁瑣的工作,而且結(jié)果可靠。它的不適用之處是對(duì)于不同精度和工作環(huán)境要求不同的制件,澆口到底開在制件的內(nèi)表面還是外表面應(yīng)根據(jù)制件的結(jié)構(gòu)決定。加強(qiáng)筋現(xiàn)設(shè)計(jì)的液晶顯示器底座上蓋板注射模就遇到了這樣的問題:如果只考慮結(jié)構(gòu)的受力要求,支撐肋條的頂部寬度需設(shè)計(jì)成2,再加上脫模斜度,則肋條根部最厚要達(dá)3.3,注射成型時(shí),塑件表面將會(huì)產(chǎn)生收縮痕。如果改變肋條的寬度,將根部的壁厚控制為基礎(chǔ)面厚度的(0.50.6)t,則其強(qiáng)度又不能滿足要求,因?yàn)槊姘迳系睦邨l要輔助支撐整機(jī)的重量。由于肋條頂部寬度僅有0.8,在注射成型時(shí),會(huì)出現(xiàn)難以充填的情況。收縮與壁厚在模具設(shè)計(jì)中確定模腔尺寸時(shí)應(yīng)考慮制品的收縮指數(shù),因而在模擬中給出制品的收縮指數(shù)是非常有意義的。經(jīng)模擬分析可知,在制品的平均壁厚為1.57754、2.29101、2.3972和2.58047mm時(shí),制品表面收縮非常不均勻。而當(dāng)平均壁厚為2.45497和2.52095mm時(shí),制品表面的收縮比較均勻,且最大收縮指數(shù)都在0.04左右。選擇計(jì)算機(jī)顯示器底座為研究對(duì)象,運(yùn)用正交試驗(yàn)法,利用HSCAE軟件對(duì)其壁厚進(jìn)行了優(yōu)化設(shè)計(jì),總結(jié)分析如下:1) 當(dāng)選擇最小壁厚值成型該塑件時(shí),即主要壁厚為1.3mm(平均厚度為1.57754mm)時(shí),16個(gè)模擬方案中有5個(gè)方案發(fā)生了短射現(xiàn)象,即熔體不能充滿型腔。而其它11個(gè)方案雖可成型,但是制品的成型質(zhì)量差,且保壓結(jié)束后制品表面的壓力分布以及收縮指數(shù)也很不均勻。因此,該塑件最好不采用最小壁厚值成型。2) 比較其它5個(gè)壁厚值時(shí)的成型效果,可知當(dāng)將主要壁厚修改為3mm(平均壁厚為2.45497mm)和3.15mm(平均壁厚為2.52095mm)時(shí),制品成型質(zhì)量最佳,其制品表面熔接痕非常少,且溫度場(chǎng)、壓力場(chǎng)、剪切力場(chǎng)、剪切速率場(chǎng)和收縮指數(shù)較其它3個(gè)壁厚值時(shí)的成型效果更為均勻、合理。但其也有不足的地方,如平均壁厚為2.45497mm時(shí),制品表面的局部區(qū)域溫度高、剪切應(yīng)力大,不過范圍很小。平均壁厚為2.52095mm時(shí),在澆口周圍壓力分布不十分均勻,但其壓力差不超過2MPa。而選擇其它3個(gè)壁厚值成型時(shí),塑件表面熔接痕都較多。其中,當(dāng)將主要壁厚修改為2.7mm時(shí),制品表面溫度分布很不均勻,最大溫差達(dá)到了120,且制品表面收縮也很不均勻,這會(huì)導(dǎo)致制品發(fā)生很大的翹曲變形。當(dāng)將主要壁厚修改為2.85mm(平均壁厚為2.3972mm)和3.3mm(平均壁厚為2.58047mm)時(shí),制品表面存在局部熱點(diǎn),且壓力場(chǎng)、剪切應(yīng)力場(chǎng)、剪切速率場(chǎng)以及收縮指數(shù)都存在局部不均的現(xiàn)象。最終,確定該塑件較為合理的壁厚成型范圍為將主要壁厚值設(shè)定在3mm(平均壁厚為2.45497mm)3.15mm(平均壁厚為2.52095mm)左右??偨Y(jié)綜上所述,電腦顯示器底座的設(shè)計(jì)方法、結(jié)構(gòu)和工業(yè)是電腦顯示器底座注射模具設(shè)計(jì)的依據(jù)。通過目前對(duì)相近也相關(guān)方面做出的研究結(jié)果,取得顯示器底座在前人試驗(yàn)條件下的真實(shí)數(shù)據(jù),找到影響顯示器底座性能提高的因素,將其用于設(shè)計(jì)中,期望順利設(shè)計(jì)出制件。
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