ZL50裝載機(jī)總體及工作裝置設(shè)計(jì)
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重 慶 理 工 大 學(xué)
文 獻(xiàn) 翻 譯
二級(jí)學(xué)院 重慶理工大學(xué)機(jī)械工程學(xué)院
班 級(jí) 109040205
學(xué)生姓名 林洋 學(xué) 號(hào) 10904020511
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1、譯文內(nèi)容必須與課題(或?qū)I(yè))內(nèi)容相關(guān),并需注明詳細(xì)出處。
2、外文翻譯譯文不少于2000字;外文參考資料閱讀量至少3篇(相當(dāng)于10萬(wàn)外文字符以上)。
3、譯文原文(或復(fù)印件)應(yīng)附在譯文后備查。
譯 文 評(píng) 閱
導(dǎo)師評(píng)語(yǔ)(應(yīng)根據(jù)學(xué)?!白g文要求”,對(duì)學(xué)生外文翻譯的準(zhǔn)確性、翻譯數(shù)量以及譯文的文字表述情況等作具體的評(píng)價(jià))
指導(dǎo)教師:
年 月 日
1
機(jī)械設(shè)計(jì)是一門(mén)通過(guò)設(shè)計(jì)新產(chǎn)品或者改進(jìn)老產(chǎn)品來(lái)滿(mǎn)足人類(lèi)需求的應(yīng)用技術(shù)科學(xué)。它涉及工程技術(shù)的各個(gè)領(lǐng)域,主要研究產(chǎn)品的尺寸、形狀和詳細(xì)結(jié)構(gòu)的基本構(gòu)思,還要研究產(chǎn)品在制造、銷(xiāo)售和使用等方面的問(wèn)題。
進(jìn)行各種機(jī)械設(shè)計(jì)工作的人員通常被稱(chēng)為設(shè)計(jì)人員或者機(jī)械設(shè)計(jì)工程師。機(jī)械設(shè)計(jì)是一項(xiàng)創(chuàng)造性的工作。設(shè)計(jì)工程師不僅在工作上要有創(chuàng)造性,還必須在機(jī)械制圖、運(yùn)動(dòng)學(xué)、工程材料、材料力學(xué)和機(jī)械制造工藝學(xué)等方面具有深厚的基礎(chǔ)知識(shí)。
如前所訴,機(jī)械設(shè)計(jì)的目的是生產(chǎn)能夠滿(mǎn)足人類(lèi)需求的產(chǎn)品。發(fā)明、發(fā)現(xiàn)和科技知識(shí)本身并不一定能給人類(lèi)帶來(lái)好處,只有當(dāng)它們被應(yīng)用在產(chǎn)品上才能產(chǎn)生效益。因而,應(yīng)該認(rèn)識(shí)到在一個(gè)特定的產(chǎn)品進(jìn)行設(shè)計(jì)之前,必須先確定人們是否需要這種產(chǎn)品。
應(yīng)當(dāng)把機(jī)械設(shè)計(jì)看成是機(jī)械設(shè)計(jì)人員運(yùn)用創(chuàng)造性的才能進(jìn)行產(chǎn)品設(shè)計(jì)、系統(tǒng)分析和制定產(chǎn)品的制造工藝學(xué)的一個(gè)良機(jī)。掌握工程基礎(chǔ)知識(shí)要比熟記一些數(shù)據(jù)和公式更為重要。僅僅使用數(shù)據(jù)和公式是不足以在一個(gè)好的設(shè)計(jì)中做出所需的全部決定的。另一方面,應(yīng)該認(rèn)真精確的進(jìn)行所有運(yùn)算。例如,即使將一個(gè)小數(shù)點(diǎn)的位置放錯(cuò),也會(huì)使正確的設(shè)計(jì)變成錯(cuò)誤的。
一個(gè)好的設(shè)計(jì)人員應(yīng)該勇于提出新的想法,而且愿意承擔(dān)一定的風(fēng)險(xiǎn),當(dāng)新的方法不適用時(shí),就使用原來(lái)的方法。因此,設(shè)計(jì)人員必須要有耐心,因?yàn)?所花費(fèi)的時(shí)間和努力并不能保證帶來(lái)成功。一個(gè)全新的設(shè)計(jì),要求屏棄許多陳舊的,為人們所熟知的方法。由于許多人墨守成規(guī),這樣做并不是一件容易的事。一位機(jī)械設(shè)計(jì)師應(yīng)該不斷地探索改進(jìn)現(xiàn)有的產(chǎn)品的方法,在此過(guò)程中應(yīng)該認(rèn)真選擇原有的、經(jīng)過(guò)驗(yàn)證的設(shè)計(jì)原理,將其與未經(jīng)過(guò)驗(yàn)證的新觀念結(jié)合起來(lái)。
2
Goldschmidt的工作是建立在建筑的方面,包含了深刻的見(jiàn)解。她指出設(shè)計(jì)師總是使用通過(guò)畫(huà)草圖使意象生成的新形式的組合。同時(shí),她補(bǔ)充說(shuō),至關(guān)重要的是設(shè)計(jì)師們也必須在相反的過(guò)程,即在他們的腦海里用他們素描生成圖像的形式。她斷言,通過(guò)互動(dòng)意象素描是一種合理的推理模式,通過(guò)系統(tǒng)概念和音形參數(shù)之間的交流。
很明顯,從藝術(shù)領(lǐng)域到工程領(lǐng)域,幾乎所有的設(shè)計(jì)師都需要可視化的設(shè)計(jì)方式。然而,區(qū)分視覺(jué)設(shè)計(jì)的表述方法很重要:哪些是以交流為目的的通信(與客戶(hù)、同事或利害關(guān)系人),哪些是用于評(píng)價(jià)設(shè)計(jì)的質(zhì)量。以上兩者都不是由視覺(jué)設(shè)計(jì)的意義,相對(duì)其描述,它應(yīng)該是促使新思想的產(chǎn)生、推理以及便于找出引發(fā)它們的創(chuàng)作的設(shè)計(jì)形式。
草圖設(shè)計(jì)在解決創(chuàng)造性、探索性、無(wú)期限待解決問(wèn)題上,通過(guò)側(cè)面的轉(zhuǎn)換發(fā)揮了重要的作用。正如加納記錄的,通過(guò)設(shè)計(jì)和以草圖的形式構(gòu)建的繪畫(huà)的表示方法,因?yàn)槠湓谝环矫婵梢哉碛行蛞子诶斫?而另一方面他們又對(duì)解釋的含糊不清。關(guān)鍵是這種方法非常缺乏明確性。很明顯,有很多的研究,對(duì)現(xiàn)有的概念草圖,目的是以電腦為依托,通過(guò)媒體實(shí)現(xiàn)目的和潛力。然而,關(guān)于直接用于汽車(chē)概念草圖的研究很少,是否有足夠的能力支持生產(chǎn)和他們計(jì)算機(jī)的使用。在工業(yè)領(lǐng)域和CAD有關(guān)的,在一個(gè)越來(lái)越大的壓力下,減少訂貨至交貨的時(shí)間仍然是一個(gè)待研究的領(lǐng)域。
3
新材料如雙相鋼或鋁復(fù)雜的幾何形狀的工業(yè)零件增加獲得無(wú)缺陷部分的沖壓的困難。一個(gè)更好的解決之道是調(diào)節(jié)壓邊壓力。我們的工作是根據(jù)H?ussermann和Haller原來(lái)的想法。我們的目標(biāo)是控制運(yùn)動(dòng)下的壓邊的空白。有了可變形的柔性壓邊,有可能創(chuàng)造一些獨(dú)立的區(qū)域。在每個(gè)區(qū)域中,一個(gè)壓邊力可以施加在片材上,因此,一個(gè)強(qiáng)大的力可容納空白區(qū),和一個(gè)較小的空白區(qū),可以讓這個(gè)力在另一個(gè)區(qū)域中移動(dòng)。關(guān)于前門(mén)板壓邊力的優(yōu)化一些方法以及一些解決結(jié)果,通常使用數(shù)值模擬進(jìn)行ABAQUS明確,有限的參數(shù)元模型(網(wǎng)格密度,沖擊速度)用最少的仿真時(shí)間達(dá)到良好的預(yù)測(cè)。 定義目標(biāo)函數(shù),以盡量減少?zèng)_頭的工作。 3個(gè)不等式約束函數(shù)的定義是為了避免頸縮起皺。為了避免縮頸,坯料的主要應(yīng)力是有限的值,這是確定通過(guò)使用修改過(guò)的最大的力標(biāo)準(zhǔn)(MMFC)。Labergere提出,為了避免起皺,要在下壓邊,角之間的壓邊的空白的表面和一個(gè)元件被限制在由用戶(hù)設(shè)定的值。然而,它是由Batoz提出,在工件的有用部分,主要的應(yīng)力被限制到一個(gè)值。最佳的本地化,我們使用了響應(yīng)面法彌漫性近似計(jì)算,再加上一個(gè)適應(yīng)性的策略,以更新的研究空間。
4
本文從一個(gè)簡(jiǎn)單的介紹,關(guān)于金屬板材成形數(shù)值模擬的必要性和復(fù)雜的汽車(chē)覆蓋件成形,有限元分析(FEA),這是一個(gè)功能強(qiáng)大的仿真工具,用于分析復(fù)雜的三維金屬板材成形問(wèn)題,以及它們的動(dòng)態(tài)顯式有限元方法的原理及特點(diǎn),本文介紹和討論了現(xiàn)有的各種商業(yè)有限元方法代碼用于金屬板材成形數(shù)值模擬在世界,國(guó)內(nèi)和國(guó)際地位的汽車(chē)覆蓋件仿真。前門(mén)外板的一個(gè)一定的新車(chē)被視為作為一個(gè)例子,動(dòng)態(tài)顯式有限元代碼。 Dynaform軟件用于在前門(mén)的外板形成過(guò)程的仿真。如破裂過(guò)程中的缺陷進(jìn)行了預(yù)測(cè)。改進(jìn)方法可以幫助解決仿真結(jié)果。金屬板材成形模擬的前景概述。
附錄
1
“The machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.
Carries on each kind of machine design work to be usually called designs the personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineering material, materials mechanics and machine manufacture technology has the deep elementary knowledge.
If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product.
Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.
A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons absolutely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.”
2
“The work of Goldschmidt in this area, also based on architecture, is telling, and contains powerful insights. She deduces that designers invariably use imagery to generate new form combinations that they represent through sketching. Crucially, she adds that they also work in the opposite way; they sketch to generate images of forms in their minds. She asserts that interactive imagery through sketching is a rational mode of reasoning characterized by systematic exchanges between conceptual and figural arguments.
It is clear that the need for visualization is recognized by almost all designers in diverse fields, from the arts to engineering. However, it is important to distinguish between that visual representation which is for the purposes of communication (with clients, colleagues or other interested parties) and that which is used for evaluation; that is to assess the quality of the design. Neither of these is what is meant by visual thinking. Rather it is the generation of new ideas, the reasoning that gives rise to them and facilitates the creation of form in designs (as opposed to their presentation).
Sketches play an important role in the creative, explorative, open-ended phase of problem solving, facilitated by lateral transformations. As Garner notes: Pictorial representations, constructed during designing and taking the form of sketches, are important to designing because they impose both order and tangibility on the one hand, while on the other hand their ambiguity stimulates re-interpretation. The very lack of clarity may be important. It is apparent that there is a wealth of existing research concerning the concept sketch; the purpose it has, the media through which it is achieved and its potential for being supported by computers. There is, however, very little research directly pertaining to the automotive concept sketch and whether it is possible to support the production and use of them using computers. In an industry heavily committed to CAD and where there is an increasing pressure to reduce lead times it is an area full of research opportunity”
3
“New materials such as dual phase steel or aluminum and complex geometries of industrial parts increase the difficulties to obtain a defect free part by stamping. One way of solution is a better regulation of the blank holder pressures. Our work is based on an original idea of Siegert, H?ussermann and Haller [1, 2, 3]. The goal is to control the movement of the blank under the blank holder. Thanks to a deformable flexible blank holder, it is possible to create some independent zones. In each zone, a blank holder force can be applied on the sheet, so that a strong force can hold the blank in a zone, and a smaller one can let it move in another zone. The methodology is presented as well as some results dealing with the optimization of the blank holder force considering the drawing of a front door panel (Numisheet’99 benchmark test). The numerical simulations are performed using ABAQUS Explicit. The parameters of the finite element model (mesh density, speed of punch) are set to achieve a good prediction with a minimum simulation time. The objective function is defined to minimize the work of the punch. Three inequality constraints functions were defined to avoid necking and wrinkling. To avoid necking, the major stress of the blank is limited to a value, which is determined by using the modified maximum force criterion (MMFC) [4]. To avoid wrinkling, under the blank holder, the angle between the blank holder surface and an element of the blank is limited to a value set by the user, as proposed by Gelin and Labergere [5]. However, in the useful part of the workpiece, the major stress is limited to a value, which was proposed by Brunet, Batoz and Bouabdallah [6]. For the localization of the optimum, we use a response surface method computed with a diffuse approximation and coupled with an adaptative strategy to update the research space.”
4
“The paper starts with a brief overview to the necessity of sheet metal forming simulation and the complexity of automobile panel forming, then leads to finite element analysis (FEA) which is a powerful simulation tool for analyzing complex three-dimensional sheet metal forming problems. The theory and features of the dynamic explicit finite element methods are introduced and the available various commercial finite element method codes used for sheet metal forming simulation in the world are discussed, and the civil and international status of automobile panel simulation as well. The front door outer panel of one certain new automobile is regarded as one example that the dynamic explicit FEM code. Dynaform is used for the simulation of the front door outer panel forming process. Process defects such as ruptures are predicted. The improving methods can be given according to the simulation results. Foreground of sheet metal forming simulation is outlined.”
參考文獻(xiàn):
[1]桂慧.機(jī)械專(zhuān)業(yè)英語(yǔ). 國(guó)防工業(yè)出版社.2009
[2]M. Tovey and S. Porter, School of Art and Design ,Coventry University ,Priory St .,Coventry . Sketching, concept development and automotive design.
[3]張揚(yáng).連洪.李雙義.王洪志.板料成形模擬及其在汽車(chē)覆蓋件沖壓過(guò)程中的應(yīng)用. 中國(guó)科學(xué)院上海冶金研究所.材料物理與化學(xué)(專(zhuān)業(yè)) 博士論文 2000
壓邊圈應(yīng)該在這個(gè)位置,做成一體的意思是不是指,壓邊圈直接放置在凹模上,不用去設(shè)計(jì)壓邊圈的模座?
這兩個(gè)防磨板是不是應(yīng)該和壓邊圈的模座進(jìn)行導(dǎo)向定位?
這兩個(gè)都有問(wèn)題!看看紅色說(shuō)明和發(fā)過(guò)來(lái)的圖片以及PPT
這個(gè)模座是不是還未完成?凹模座的導(dǎo)板還未定位?
這是我原先想要設(shè)計(jì)想法的來(lái)源,這里的防磨板應(yīng)該是和binder導(dǎo)向,現(xiàn)在這個(gè)版本的草圖是不是不應(yīng)該再用?
應(yīng)該是這個(gè)版本的結(jié)構(gòu)!上面結(jié)構(gòu)不正確。
Binder
Punch(凸模)用螺釘固定在凸模座上,用銷(xiāo)釘在凸模座上定位,四周加上導(dǎo)向裝置,壓邊圈放在凸模座與凸模之間的空間內(nèi)
Die(凹模)與凹模座是一個(gè)整體
這是上一屆學(xué)生設(shè)計(jì)的藍(lán)本,這里的binder與die之間的定位方式是什么?他的die和punch之間的定位是否就是老師您的要求?
binder與die之間無(wú)任何定位關(guān)系!
這句話不理解,凹模和凹模座一個(gè)整體,但是凹模和壓邊圈怎么一個(gè)整體?
老師這兩個(gè)零件是什么?是不是它的壓邊零件?
這是我的壓邊圈 ,請(qǐng)老師幫我指出壓邊零件安裝的位置?
這是我設(shè)計(jì)的頂桿。。。。。
凸模座
壓邊圈
凹模座
插入銷(xiāo)釘和內(nèi)六角螺釘
凸模
編號(hào)
畢業(yè)設(shè)計(jì)(論文)
題目 某轎車(chē)引擎蓋外板拉深模具設(shè)計(jì)及成形模擬
二級(jí)學(xué)院 機(jī)械工程學(xué)院
專(zhuān) 業(yè) 機(jī)械設(shè)計(jì)制造及其自動(dòng)化
班 級(jí) 109040205
學(xué)生姓名 林洋 學(xué)號(hào) 10904020511
指導(dǎo)教師 王昶
評(píng)閱教師
時(shí) 間
重慶理工大學(xué)畢業(yè)論文 文獻(xiàn)綜述
轎車(chē)A級(jí)面覆蓋件成形技術(shù)發(fā)展
林洋
( 重慶理工大學(xué) 機(jī)械工程學(xué)院 ,重慶 40054 )
摘要:通過(guò)對(duì)某轎車(chē)車(chē)身覆蓋件的引擎蓋外板拉深模具型面的設(shè)計(jì),介紹了復(fù)雜型面拉深件拉深模具型面的設(shè)計(jì)流程,研究了復(fù)雜型面拉深件拉深模具型面的造型設(shè)計(jì)方法和原則。利用板料成形分析有限元軟件Dynaform對(duì)引擎蓋外板的拉深成形過(guò)程進(jìn)行仿真模擬,探討了仿真過(guò)程中出現(xiàn)的質(zhì)量缺陷(如破裂、起皺、變形不足等)的原因,并針對(duì)這些現(xiàn)象對(duì)拉深模具型面進(jìn)行優(yōu)化設(shè)計(jì)改進(jìn)。并根據(jù)仿真模擬結(jié)果,制造加工了合格的拉深件模具。對(duì)于復(fù)雜型面拉深件的拉深模具的設(shè)計(jì)和制造具有一定的指導(dǎo)意義。
關(guān)鍵詞:車(chē)身覆蓋件;沖壓成形;模具;優(yōu)化設(shè)計(jì);有限元分析
Abstract: The designing process of drawing die for complex surface drawing part in designing the drawing model of the automotive hood outer panel surface and the design method and principle were studied. The stamping process using the sheet metal forming analysis software Dynaform was simulated. The reason causing quality defect in simulation, such as cracking and wrinkle etc., was investigated. Based on these reasons, the design of drawing die surface for automobile hood outer panel was optimized. According to the simulated results, the qualified drawing die was made, which had a instructing meaning for the
design and manufacture of drawing die for complex surface drawing part.
前言
隨著汽車(chē)工業(yè)的迅猛發(fā)展,車(chē)型的多樣化、個(gè)性化已經(jīng)成為汽車(chē)發(fā)展的趨勢(shì)。而汽車(chē)引擎蓋設(shè)計(jì)是汽車(chē)設(shè)計(jì)中的重要環(huán)節(jié)之一。它是屬于汽車(chē)覆蓋件上的一部分,汽車(chē)覆蓋件,是指構(gòu)成汽車(chē)車(chē)身或駕駛室、覆蓋發(fā)動(dòng)機(jī)和底盤(pán)的異形體表面和內(nèi)部的汽車(chē)零件。汽車(chē)覆蓋件既是外觀裝飾性的零件,又是封閉薄殼狀的受力零件。在對(duì)汽車(chē)性能要求越來(lái)越高的今天,對(duì)于汽車(chē)而言,任何一個(gè)零件的設(shè)計(jì)都將影響到汽車(chē)的性能。
本設(shè)計(jì)基于某轎車(chē)引擎蓋外板,利用了計(jì)算機(jī)Dynaform,UG等軟件的模擬計(jì)算及建模,深入探討了轎車(chē)引擎蓋模具設(shè)計(jì)以及成型模擬分析等問(wèn)題,從而使乘用車(chē)的流暢性與動(dòng)力性進(jìn)一步提高。
一、 汽車(chē)工業(yè)發(fā)展趨勢(shì)與汽車(chē)零件成形
汽車(chē)覆蓋件的成形工藝和模具制造技術(shù)是先進(jìn)制造技術(shù)的重要組成部分,“汽車(chē)工業(yè)作為資金和技術(shù)密集的支柱產(chǎn)業(yè)之一,充分將信息技術(shù)和傳統(tǒng)制造技術(shù)相結(jié)合,展現(xiàn)了現(xiàn)代設(shè)計(jì)、先進(jìn)制造工藝和設(shè)備、制造業(yè)自動(dòng)化、系統(tǒng)管理、綜合集成等現(xiàn)代化先進(jìn)制造技術(shù)。政府在2005年開(kāi)始圍繞節(jié)能、安全與環(huán)保三大戰(zhàn)略,鼓勵(lì)在汽車(chē)工業(yè)中的各種新車(chē)型及零部件制造中采用先進(jìn)制造技術(shù),對(duì)新能源、新材料、新工藝技術(shù)進(jìn)行開(kāi)發(fā),并將這作為現(xiàn)代汽車(chē)生產(chǎn)企業(yè)的技術(shù)發(fā)展方向和重點(diǎn)。在車(chē)身零部件中,絕大部分都需要采用沖壓工藝獲得,因此,在汽車(chē)車(chē)身開(kāi)發(fā)中,汽車(chē)零部件的成形技術(shù),尤其是覆蓋件的成形工藝技術(shù)和模具制造技術(shù)占據(jù)至關(guān)重要的地位”。從上述的文獻(xiàn)中,不難發(fā)現(xiàn)汽車(chē)工業(yè)已經(jīng)成為世界發(fā)達(dá)國(guó)家一大支柱,而我國(guó)引進(jìn)國(guó)外先進(jìn)的技術(shù)勢(shì)在必行,世界經(jīng)濟(jì)一體化給我國(guó)帶來(lái)了機(jī)遇和挑戰(zhàn),我國(guó)汽車(chē)工業(yè)迅速興起,從數(shù)量上已成為了汽車(chē)大國(guó)。世界各國(guó)汽車(chē)公司都爭(zhēng)先恐后地涌入我國(guó),由原先向中國(guó)出口汽車(chē),轉(zhuǎn)為在中國(guó)國(guó)內(nèi)合作生產(chǎn)汽車(chē),并帶來(lái)了大量先進(jìn)技術(shù)。其中汽車(chē)各個(gè)覆蓋件的模具設(shè)計(jì)就成為一個(gè)典型例子。
二、覆蓋件的特點(diǎn)和要求
同一般沖壓件相比,覆蓋件具有材料薄、形狀復(fù)雜、結(jié)構(gòu)尺寸大和表面質(zhì)量要求高等特點(diǎn)。覆蓋件的工藝設(shè)計(jì)、沖模結(jié)構(gòu)設(shè)計(jì)和沖模制造工藝都具有特殊性。因此,在實(shí)踐中常把覆蓋件從一般沖壓件中分離出來(lái),作為一各特殊的類(lèi)別加以研究和分析。覆蓋件的特點(diǎn)決定了它的特殊要求。
2.1 表面質(zhì)量
覆蓋件表面上任何微小的缺陷都會(huì)在涂漆后引起光線的漫反射而損壞外形的美觀,因此覆蓋件表面不允許有波紋、皺折、凹痕、擦傷、邊緣拉痕和其他破壞表面美感的缺陷。覆蓋件上的裝飾棱線和筋條要求清晰、平滑、左右對(duì)稱(chēng)和過(guò)渡均勻,覆蓋件之間的棱線銜接應(yīng)吻合流暢,不允許參差不齊。總之覆蓋件不僅要滿(mǎn)足結(jié)構(gòu)上的功能要求,更要滿(mǎn)足表面裝飾的美觀要求。
2.2 尺寸形狀
覆蓋件的形狀多為空間立體曲面,其形狀很難在覆蓋件圖上完整準(zhǔn)確地表達(dá)出來(lái),因此覆蓋件的尺寸形狀常常借助主模型來(lái)描述。主模型是覆蓋件的主要制造依據(jù),覆蓋件圖上標(biāo)注出來(lái)的尺寸形狀,其中包括立體曲面形狀、各種孔的位置尺寸、形狀過(guò)渡尺寸等,都應(yīng)和主模型一致,圖面上無(wú)法標(biāo)注的尺寸要依賴(lài)主模型量取,從這個(gè)意義上看,主模型是覆蓋件圖必要的補(bǔ)充。
2.3 剛性
覆蓋件拉延成型時(shí),由于其塑性變形的不均勻性,往往會(huì)使某些部位剛性較差。剛性差的覆蓋件受至振動(dòng)后會(huì)產(chǎn)生空洞聲,用這樣零件裝車(chē),汽車(chē)在高速行駛時(shí)就會(huì)發(fā)生振動(dòng),造成覆蓋件早期破壞,因此覆蓋件的剛性要求不可忽視。檢查覆蓋件剛性的方法,一是敲打零件以分辨其不同部位聲音的異同,另一是用手按看其是否發(fā)生松弛和鼓動(dòng)現(xiàn)象。
2.4 工藝性
覆蓋件的結(jié)構(gòu)形狀和尺寸決定該件的工藝性。覆蓋件的工藝性關(guān)鍵是拉延工藝性。覆蓋件一般都采用一次成型法,為了創(chuàng)造一個(gè)良好的拉延條件,通常將翻邊展開(kāi),窗口補(bǔ)滿(mǎn),再加添上工藝補(bǔ)充部分,構(gòu)成一個(gè)拉延件。
三、傳統(tǒng)工藝與現(xiàn)代工藝CAE的應(yīng)用
首先來(lái)說(shuō),現(xiàn)代工業(yè)的進(jìn)步,完全得力于計(jì)算機(jī)技術(shù)的突飛猛進(jìn),因此由20世紀(jì)進(jìn)入21世紀(jì),引導(dǎo)人類(lèi)科技再次進(jìn)步的必然是與計(jì)算機(jī)結(jié)合的科技。而計(jì)算機(jī)軟件的應(yīng)用與發(fā)展也得力于計(jì)算機(jī)科技的進(jìn)步,將計(jì)算機(jī)、計(jì)算機(jī)軟件用于產(chǎn)品的開(kāi)發(fā)、設(shè)計(jì)、分析與制造,已成為近代工業(yè)提升競(jìng)爭(zhēng)力的主要方法。
“傳統(tǒng)的工業(yè)皆依據(jù)個(gè)人的經(jīng)驗(yàn)累積而成,同時(shí)以經(jīng)驗(yàn)做出初步的設(shè)計(jì),再由此初步的設(shè)計(jì)去做出原始模型,再做出成品。成品完成以后,使進(jìn)行試驗(yàn)以確保產(chǎn)品的可靠性”,而此種方法基本上稱(chēng)為試湊法,此種方法費(fèi)時(shí)且成本相當(dāng)?shù)母摺!叭羰褂肅AE,則在設(shè)計(jì)圖完成后即連接CAE,做各式各樣的分析,并且導(dǎo)入最優(yōu)化成品,即可在短時(shí)間內(nèi)完成成品”,“機(jī)構(gòu)動(dòng)力的傳動(dòng)可以借著機(jī)構(gòu)系統(tǒng)仿真軟件來(lái)虛擬各組件之間的有可能產(chǎn)生的摩擦力或接觸力”。有上述文件可以看見(jiàn),隨著高性能計(jì)算機(jī)系統(tǒng)的發(fā)展,CAE軟件將成為工程師實(shí)現(xiàn)其工程創(chuàng)新和產(chǎn)品創(chuàng)新的得力助手和有效工具。人們使用CAE軟件,對(duì)其創(chuàng)新的設(shè)計(jì)方案快速實(shí)施性能與可靠性分析,并進(jìn)行虛擬運(yùn)行模擬,及早發(fā)現(xiàn)設(shè)計(jì)缺陷,在實(shí)現(xiàn)創(chuàng)新的同時(shí),提高設(shè)計(jì)質(zhì)量,降低研究開(kāi)發(fā)成本,縮短研究開(kāi)發(fā)周期。可以預(yù)測(cè)在未來(lái)的發(fā)展中,CAE軟件的發(fā)展和應(yīng)用就像當(dāng)年CAD軟件的使用一樣得到普及。因此,對(duì)于機(jī)械工程類(lèi)的學(xué)生掌握一門(mén)CAE軟件技術(shù)已成為了時(shí)代的需要。
汽車(chē)引擎蓋的設(shè)計(jì)及分析對(duì)汽車(chē)設(shè)計(jì)具有極重要的意義,通過(guò)本文的研究和探索,結(jié)合研究中的不足之處,可以總結(jié)出以后研究的具體內(nèi)容: 1、繼續(xù)學(xué)習(xí)深化汽車(chē)覆蓋件的相關(guān)知識(shí),掌握現(xiàn)代分析方法。 2、對(duì)引擎蓋外拉板優(yōu)化設(shè)計(jì),模擬裝配并通過(guò)CAE分析軟件分析以獲得更好的模具。
參考文獻(xiàn):
[1]練章華.現(xiàn)代CAE技術(shù)與應(yīng)用教程. 北京:石油工業(yè)出版社,2004.12
[2]陽(yáng)春?jiǎn)?李玉強(qiáng),楊旭,龔志輝.先進(jìn)制造技術(shù)在汽車(chē)覆蓋件模具制造中的應(yīng)用.
[3]王衛(wèi)兵.CimatronE模具設(shè)計(jì)與數(shù)控編程實(shí)例教程[M].北京:清華大學(xué)出版社,2005
[4]王昶,李琳,王萍,胡亞民.轎車(chē)引擎蓋外板拉深模具型面的設(shè)計(jì)及優(yōu)化[J].鍛壓技術(shù).第33卷第2期.2008.[5]萬(wàn)戰(zhàn)勝,顧圣巖,龐銳.沖壓模具設(shè)計(jì)[M].北京. 中國(guó)鐵道出版社.1983.
[6]張秉璋.板料沖壓模具設(shè)計(jì)[M].西安.西安工業(yè)大學(xué)出版社.1997.
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