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編號(hào)
無(wú)錫太湖學(xué)院
畢業(yè)設(shè)計(jì)(論文)
相關(guān)資料
題目: 偏心導(dǎo)桿調(diào)速器
信機(jī) 系 機(jī)械工程及自動(dòng)化專業(yè)
學(xué) 號(hào): 0923188
學(xué)生姓名: 趙操超
指導(dǎo)教師: 唐正寧 (職稱:副教授 )
(職稱: )
2013年5月25日
目 錄
一、畢業(yè)設(shè)計(jì)(論文)開(kāi)題報(bào)告
二、畢業(yè)設(shè)計(jì)(論文)外文資料翻譯及原文
三、學(xué)生“畢業(yè)論文(論文)計(jì)劃、進(jìn)度、檢查及落實(shí)表”
四、實(shí)習(xí)鑒定表
無(wú)錫太湖學(xué)院
畢業(yè)設(shè)計(jì)(論文)
開(kāi)題報(bào)告
題目: 偏心導(dǎo)桿調(diào)速器
信機(jī) 系 機(jī)械工程及自動(dòng)化 專業(yè)
學(xué) 號(hào): 0923188
學(xué)生姓名: 趙操超
指導(dǎo)教師: 唐正寧 (職稱:副教授 )
(職稱: )
2012年 11月12日
課題來(lái)源
自擬題目
科學(xué)依據(jù)(包括課題的科學(xué)意義;國(guó)內(nèi)外研究概況、水平和發(fā)展趨勢(shì);應(yīng)用前景等)
(1) 課題科學(xué)意義
調(diào)速器用于減小某些機(jī)器非周期性速度波動(dòng)的自動(dòng)調(diào)節(jié)裝置??墒箼C(jī)器轉(zhuǎn)速保持定值或接近設(shè)定值。水輪機(jī)、汽輪機(jī)、燃?xì)廨啓C(jī)和內(nèi)燃機(jī)等與電動(dòng)機(jī)不同,其輸出的力矩不能自動(dòng)適應(yīng)本身的載荷變化,因而當(dāng)載荷變動(dòng)時(shí),由它們驅(qū)動(dòng)的機(jī)組就會(huì)失去穩(wěn)定性。這類機(jī)組必須設(shè)置調(diào)速器,使其能隨著載荷等條件變化,隨時(shí)建立載荷與能源供給量之間的適應(yīng)關(guān)系,以保證機(jī)組作正常運(yùn)轉(zhuǎn)。調(diào)速器的理論和設(shè)計(jì)問(wèn)題,是機(jī)械動(dòng)力學(xué)的研究?jī)?nèi)容。調(diào)速器的種類很多。其中應(yīng)用最廣泛的是機(jī)械式離心調(diào)速器。而以測(cè)速發(fā)電機(jī)或其他電子器件作為傳感器的調(diào)速器,已在各個(gè)工業(yè)部門(mén)中廣為應(yīng)用。
調(diào)速器的種類很多,按其工作原理的不同可分為機(jī)械式、氣動(dòng)式、液動(dòng)式、機(jī)械氣動(dòng)復(fù)合式和電子式等多種形式。目前應(yīng)用最廣泛的當(dāng)屬機(jī)械式調(diào)速器,其結(jié)構(gòu)簡(jiǎn)單、工作可靠、性能良好。偏心導(dǎo)桿調(diào)速器也屬于機(jī)械式調(diào)速器。
(2) 偏心導(dǎo)桿調(diào)速器的研究狀況及其發(fā)展前景
目前中國(guó)從事自動(dòng)調(diào)速器生產(chǎn)的企業(yè)共有20多家,根據(jù)這些企業(yè)的已建產(chǎn)能和在建產(chǎn)能統(tǒng)計(jì),2015年中國(guó)自動(dòng)調(diào)速器產(chǎn)能將達(dá)到775萬(wàn)臺(tái)。
解放初期,我國(guó)調(diào)速器事業(yè)一片空白,幾乎從零開(kāi)始,大部分產(chǎn)品從蘇聯(lián)購(gòu)買,少量制造亦是照搬蘇聯(lián)圖紙生產(chǎn)。50~60年代,我國(guó)調(diào)速器大部分系機(jī)械液壓型調(diào)速器。在大躍進(jìn)年代,當(dāng)時(shí)的水利水電科學(xué)研究院、哈爾濱電機(jī)廠等單位曾聯(lián)合研制了我國(guó)第一臺(tái)調(diào)速器,并安裝在廣東從化流溪河水電站運(yùn)行了一段時(shí)間。60年代初,當(dāng)時(shí)的水利水電科學(xué)研究院、天津電氣傳動(dòng)設(shè)計(jì)研究所、長(zhǎng)江流域規(guī)劃辦公室等單位聯(lián)合研制了我國(guó)第一臺(tái)晶體管電液調(diào)速器,并在湖北陸水試驗(yàn)電站運(yùn)行了相當(dāng)長(zhǎng)一段時(shí)間。70年代至80年代初,新建的大中型水電站較多地采用了電子管、晶體管或小規(guī)模集成電路電液調(diào)速器,一些小型水電站也少量采用了電液調(diào)速器,此階段可算是機(jī)械液壓調(diào)速器與電氣液壓調(diào)速器并重。但電氣液壓調(diào)速器由于所選用的主要電子元件組件質(zhì)量不過(guò)關(guān),其長(zhǎng)期使用的可靠性普遍較低。
研究?jī)?nèi)容
1. 閱讀外文資料,翻譯與所學(xué)專業(yè)或課題相關(guān)的外文文獻(xiàn)5000字左右,語(yǔ)句通順、流暢、準(zhǔn)確;
2.了解偏心導(dǎo)桿調(diào)速器的工作原理;
3.根據(jù)具體結(jié)構(gòu),擬定分析設(shè)備設(shè)計(jì)方案;
4.繪制整套零件圖,裝配圖;
5. 用Pro/E進(jìn)行造型,裝配后進(jìn)行運(yùn)動(dòng)仿真;
6. 撰寫(xiě)論文,要求符合本科論文的格式要求,語(yǔ)言簡(jiǎn)潔、流暢、層次分明。上機(jī)時(shí)數(shù)不少于200小時(shí),整個(gè)畢業(yè)設(shè)計(jì)過(guò)程的技術(shù)工作要嚴(yán)謹(jǐn)、靈活、工作要有主動(dòng)性,計(jì)算方法、計(jì)算的程序、計(jì)算結(jié)果、結(jié)論要正確。
擬采取的研究方法、技術(shù)路線、實(shí)驗(yàn)方案及可行性分析
偏心導(dǎo)桿調(diào)速器主要由錐齒輪、主動(dòng)鏈輪、從動(dòng)鏈輪、導(dǎo)桿、曲柄、滑塊、標(biāo)尺、等部分組成。其工作原理是:當(dāng)主動(dòng)鏈輪輸入等角速度時(shí),由于導(dǎo)桿和曲柄的軸心線偏置,從動(dòng)鏈輪就輸出周期性的變角速度。
先松開(kāi)帶柄螺母,然后轉(zhuǎn)動(dòng)手柄對(duì)照標(biāo)尺進(jìn)行調(diào)節(jié),調(diào)節(jié)完畢后,再將帶柄螺母重新固緊。
可行性分析:通過(guò)各主要部分系統(tǒng)的確定,主要問(wèn)題可以解決。細(xì)節(jié)問(wèn)題也可以方便的處理,總的來(lái)說(shuō),此方案的可行性沒(méi)有問(wèn)題。
研究計(jì)劃及預(yù)期成果
研究計(jì)劃:
2012年11月25日-2012年12月25日:按照任務(wù)書(shū)要求查閱論文相關(guān)參考資料,填寫(xiě)畢業(yè)設(shè)計(jì)開(kāi)題報(bào)告書(shū)。
2013年1月11日-2013年3月5日:填寫(xiě)畢業(yè)實(shí)習(xí)報(bào)告。
2013年3月8 日-2013年3月14日:按照要求修改畢業(yè)設(shè)計(jì)開(kāi)題報(bào)告。
2013年3月15日-2013年3月21日:學(xué)習(xí)并翻譯一篇與畢業(yè)設(shè)計(jì)相關(guān)的英文材料。
2013年3月22日-2013年4月11日:繪制二維零件圖。
2013年4月12日-2013年4月25日:繪制三維圖。
2013年4月26日-2013年5月20日:畢業(yè)論文撰寫(xiě)和修改工作。
預(yù)期成果:
明確偏心導(dǎo)桿調(diào)速器預(yù)期達(dá)到的性能指標(biāo)和工作路線??傮w方案的設(shè)計(jì),可行性的分析。偏心導(dǎo)桿調(diào)速器的初步設(shè)計(jì),總體結(jié)構(gòu)的設(shè)計(jì),各部件的參數(shù)設(shè)計(jì)。強(qiáng)度計(jì)算,分析驗(yàn)證,優(yōu)化設(shè)計(jì)。完成二維圖和三維圖的繪制。完成三維總裝圖的動(dòng)態(tài)展示。完成設(shè)計(jì)說(shuō)明書(shū)。
特色或創(chuàng)新之處
偏心導(dǎo)桿調(diào)速器屬于常用的機(jī)械式調(diào)速器,其結(jié)構(gòu)簡(jiǎn)單、加工方便、安全性高。其特色在于能按刻度調(diào)節(jié)速度的大小,壽命長(zhǎng),不易損壞。
已具備的條件和尚需解決的問(wèn)題
① 各類資料比較齊全查閱方便;
偏心導(dǎo)桿調(diào)速器已有類似的產(chǎn)品可以參考。
② 錐齒輪的計(jì)算,軸承的壽命,標(biāo)尺的刻度等等。
指導(dǎo)教師意見(jiàn)
指導(dǎo)教師簽名:
年 月 日
教研室(學(xué)科組、研究所)意見(jiàn)
教研室主任簽名:
年 月 日
系意見(jiàn)
主管領(lǐng)導(dǎo)簽名:
年 月 日
英文原文
A knowledge-based system for materials selection in mechanical engineering design
Abstract
This paper studies various work on the development of computerized material selection system. The importance of Knowledge-based system (KBS) in the context of concurrent engineering is explained. The study of KBS in material selection in an engineering design process is described. The development in materials databases, which sometimes serve as material selection packages, is also discussed. The use of KBS in material selection and the application in the domain of polymeric-based composite are chosen as typical examples. 2001 Published by Else vier Science Ltd.
Introduction
Materials selection is a task normally carried out by design and materials engineers. Gutte ridge and Water- man [1] described the aim of materials selection as the identification of materials, which after appropriate manufacturing operations, will have the dimensions, shape and properties necessary for the product or component to demonstrate its required function at the lowest cost. For the purpose of material selection, thousands of data would be needed to characterize all the grades of materials. Many selection systems are available to help design engineers to choose the most suitable materials. At the most basic level, design engineers could use tables of material properties in data books. However, data sheets are incomplete and once published, they are difficult to update. Dadd and Fair-full [2] described how information about engineering materials, can be divided into two main categories, i.e. data and knowledge. Data is defined as the results of measurements, whereas knowledge represents the connections between items of data, the source of this knowledge, which contributes to an understanding of the results. Both the computerized database and the KBS of material selection will be described in the following sections.
The material database for materials selection
2.1. Supporting data and rigorous logic for the hypothesis and observation.
In recent years, attention is being made to the use of computer systems to store and process data regarding the properties of materials. It enables the designers to achieve large capacity and rapid retrieval from a computer database to provide easy access to the materials data.According to Prada [3], materials are the common elements enumerating parts in a product realization process. Nowadays, design engineers normally rely on the materials that they are familiar with. However, when design requirements exceed the constraints of such materials or exceed the constraints on material properties, concurrent engineering teams must consider alternative materials. With direct online access to a materials database, the concurrent engineering teams could select materials that are lighter, stronger and lower in cost. Assuming that the impact of such substitutions can be analyzed or simulated, the teams could easily make an optimum selection of materials for the available processes,conserve materials for each process and thus, reduce material waste. White [4] emphasized the importance of computer aided materials selection as books have several drawbacks as they are often outdated before reaching the bookshelves. It is very difficult to index them to find answers or to sort data in the manner of your choice. A computerized system, which provides access to materials data, is not necessarily a materials selection system, although access to data is essential to facilitate selection.
2.2. Critical review
This section reviews the development of computerized materials databases that enabled designers to select the materials in mechanical engineering design application. The development of material databases has been reported by Harmer [5] , Breuer et al [6-10], Baur [11-12] , Michael [13] , Ashby [14-15] and C ebon and Ashby [16-17] .
Harmer [5] reported that various database systems have been developed for plastics, elastomers and rubbers such as the Cambridge Materials Selector (CMS) , CAMPUS, Selector II, Specula, Cen-base/Materials, Mat. DB, Plastics Design Library .Engineered Materials Abstracts, FUNDUS, Prospector Plus, Poly mat, SPAO, Pro-Concept, Explorer, Plata’polymerically, Standards Info-disk, Piura Abstracts, Packaging Science and Technology Abstracts, Chem-In-tell and Welda-search.
Computer-aided material pre-selection by uniform standards (CAMPUS) is a widely used materials database for plastics [6-10]. A product similar to that of CAMPUS is a database concerned with the selection of long fiber reinforced plastics. This system is called FUNDUS and it allows the distribution of material information from the producer to the designer end-user [11-13]. As such, it is of interest to all who work with sheet molding compound (SMC) , bulk molding compound ?.BMC or glass-mat thermoplastic (GMT) materials as reported by Baur [11-12] and Michael i et al. [13] . CAMPUS and FUNDUS have features, which allow the user to view all properties for any listed product, print the data for any product search the database for products satisfying specific property requirements, select and view properties for comparison, and sort according to specific requirement in ascending or descending order. Ashby[14, 15] and C ebon and Ashby [16-17] developed a computerized materials selection system called Cambridge Materials Selector (CMS).
The system uses materials selection charts, which are a way of displaying material property data through the use of optimization procedures. The selection process depends on implementing performance Indices, a combination of material properties, which if maximized, optimizes performance. The charts are developed to present the materials,and the performance Indices, so that the most suitable selection of materials and shape can be carried out.
Machine Design
The complete design of a machine is a complex process. 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. One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations. Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.
The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM). How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process. Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on.
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 obsoletely 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.
中文譯文
機(jī)械工程設(shè)計(jì)選材基礎(chǔ)知識(shí)
摘要
本文致力于研究對(duì)各種材料選擇的電腦化系統(tǒng)發(fā)展。并對(duì)以基礎(chǔ)知識(shí)的系統(tǒng)在并行工程環(huán)境(KBS)的重要性進(jìn)行了解釋。KBS的研究在材料選擇方面由一個(gè)工程設(shè)計(jì)過(guò)程來(lái)描述。材料數(shù)據(jù)庫(kù)的發(fā)展,和選材服務(wù),也被討論到了。在材料選擇KBS和使用中的聚合物基復(fù)合材料領(lǐng)域的應(yīng)用是選材典型的例子。2001年由Else-vier科學(xué)有限公司出版。?
1. 簡(jiǎn)介?
材料選擇通常是設(shè)計(jì)和材料工程師一項(xiàng)任務(wù)。加特里奇和水人[1]中是這樣描述選擇材料的:經(jīng)過(guò)適當(dāng)?shù)闹圃鞓I(yè)務(wù),將有尺寸,形狀和性能的產(chǎn)品或組件要以最低的成本展示其規(guī)定功能的材料選擇的目標(biāo)。對(duì)于選材的目的,成千上萬(wàn)的數(shù)據(jù)將需要所有的材料的特性。許多選擇系統(tǒng)可以幫助設(shè)計(jì)工程師選擇最合適的材料。在最基本的層面上,設(shè)計(jì)工程師可利用材料性能數(shù)據(jù)手冊(cè)表。但是,數(shù)據(jù)表是不完整的,一旦公布,他們是難以更新。多德和范福?[2]描述了有關(guān)工程材料的資料,可分為兩大類,即數(shù)據(jù)和知識(shí)的分歧。數(shù)據(jù)被定義為測(cè)量的結(jié)果,而信息代表之間的數(shù)據(jù),在這方面的知識(shí),這有助于對(duì)結(jié)果的認(rèn)識(shí)源項(xiàng)目的連接。無(wú)論是計(jì)算機(jī)化的數(shù)據(jù)庫(kù)和材料選擇的KBS將在以下各節(jié)描述。??
2. 針對(duì)對(duì)材料選擇的材料數(shù)據(jù)庫(kù)?
2.1 支持這一假設(shè)的數(shù)據(jù)和嚴(yán)密的邏輯
近年來(lái),關(guān)注正在面向計(jì)算機(jī)系統(tǒng)來(lái)存儲(chǔ)和處理數(shù)據(jù)的有關(guān)材料的性能。它使得設(shè)計(jì)者能夠在實(shí)現(xiàn)大容量和快速的從一個(gè)計(jì)算機(jī)數(shù)據(jù)庫(kù)里檢索到資料數(shù)據(jù)。據(jù)普拉薩德[3],材料是在列舉部分產(chǎn)品實(shí)現(xiàn)過(guò)程的共同要素。如今,設(shè)計(jì)工程師通常依賴于材料,他們所熟悉的。然而,當(dāng)超過(guò)設(shè)計(jì)要求這些材料的限制或超過(guò)材料特性的限制,并行工程團(tuán)隊(duì)必須考慮替代材料。隨著直接在線訪問(wèn)材料數(shù)據(jù)庫(kù),并行工程團(tuán)隊(duì)可以選擇的材料,重量更輕,更強(qiáng),成本更低。假設(shè),這種替代的影響可以分析或模擬,團(tuán)隊(duì)可以輕而易舉地把一個(gè)可用進(jìn)程的最佳選擇材料,節(jié)約每一個(gè)程序的材料,因此,減少材料浪費(fèi)是必須的。白[4]強(qiáng)調(diào)了計(jì)算機(jī)選型輔助材料的重要性,圖書(shū)有幾個(gè)缺點(diǎn),他們往往在到達(dá)的書(shū)架得時(shí)候已經(jīng)過(guò)時(shí)。這使得他們很難找到答案指標(biāo)進(jìn)行排序或在您選擇的方式的數(shù)據(jù)。電腦化系統(tǒng),它提供了訪問(wèn)數(shù)據(jù)的材料,并不一定是材料選擇系統(tǒng),雖然對(duì)數(shù)據(jù)的訪問(wèn)是必要的,以方便選擇。??
2.2?嚴(yán)格審查??
本節(jié)回顧了計(jì)算機(jī)化的材料數(shù)據(jù)庫(kù),使設(shè)計(jì)人員選擇了機(jī)械工程設(shè)計(jì)中的應(yīng)用材料的發(fā)展。材料數(shù)據(jù)庫(kù)的發(fā)展哈默曾報(bào)道[5],布魯爾等[6-10],鮑爾[11-12],Michael i?[13],阿什比[14-15]和C ebon和Ashby?[16-17]?。哈默[5]報(bào)道,各種數(shù)據(jù)庫(kù)系統(tǒng)已用于塑料,橡膠等材料的選擇劍橋(CMS)校園,選擇二,材料,橡膠墊發(fā)展。數(shù)據(jù)庫(kù),塑料設(shè)計(jì)庫(kù)。文摘工程材料,眼底,勘探者另外,市產(chǎn)管辦,臨概念,探險(xiǎn)家,普拉特的Polymers-can,標(biāo)準(zhǔn)Info-disk,皮拉文摘,包裝科學(xué)與技術(shù)文摘,化學(xué),網(wǎng)絡(luò)和搜索。?
計(jì)算機(jī)輔助材料前通過(guò)統(tǒng)一標(biāo)準(zhǔn)的選擇(CAMPUS)是一種廣泛使用的塑料材料數(shù)據(jù)庫(kù)[6-10]。一個(gè)產(chǎn)品類似CAMPUS,與長(zhǎng)纖維選擇有關(guān)的數(shù)據(jù)庫(kù)增強(qiáng)塑料。這個(gè)系統(tǒng)被稱為眼底,它允許信息從材料到設(shè)計(jì)生產(chǎn)銷售的最終用戶[11-13]。因此,它是關(guān)系到所有誰(shuí)與片狀模塑料(SMC)的,散裝模塑料(BMC)或玻璃墊熱塑性(GMT)的材料由鮑爾報(bào)道[11-12]和Michael i等。?[13]。校園及眼底有特點(diǎn),它允許用戶查看任何列出的產(chǎn)品的所有屬性,打印任何產(chǎn)品搜索數(shù)據(jù),滿足特定性能要求,選擇和查看比較性質(zhì)的產(chǎn)品數(shù)據(jù)庫(kù),并按照升序排序的具體要求或降序。阿什比[14,15]和C ebon和Ashby?[16-17]開(kāi)發(fā)一個(gè)計(jì)算機(jī)化的材料選擇系統(tǒng),稱為劍橋材料選擇器(CMS)的。該系統(tǒng)使用材料的選擇圖表,這是一種顯示,通過(guò)優(yōu)化程序使用材料性能數(shù)據(jù)的方法。甄選過(guò)程由實(shí)施性能指標(biāo)而定,一個(gè)物質(zhì)屬性的組合,而如果最優(yōu)化性能。圖表的開(kāi)發(fā),以目前的材料,和性能指標(biāo),使最合適的材料和形狀可以進(jìn)行選擇。?
機(jī)械設(shè)計(jì)
一臺(tái)完整機(jī)器的設(shè)計(jì)是一個(gè)復(fù)雜的過(guò)程。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)。
任何產(chǎn)品在設(shè)計(jì)時(shí)第一步就是選擇產(chǎn)品每個(gè)部分的構(gòu)成材料。許多的材料被今天的設(shè)計(jì)師所使用。對(duì)產(chǎn)品的功能,它的外觀、材料的成本、制造的成本作出必要的選擇是十分重要的。對(duì)材料的特性必須事先作出仔細(xì)的評(píng)估。
仔細(xì)精確的計(jì)算是必要的,以確保設(shè)計(jì)的有效性。在任何失敗的情況下,最好知道在最初設(shè)計(jì)中有有缺陷的部件。計(jì)算(圖紙尺寸)檢查是非常重要的。一個(gè)小數(shù)點(diǎn)的位置放錯(cuò)就可以導(dǎo)致一個(gè)本可以完成的項(xiàng)目失敗。設(shè)計(jì)工作的各個(gè)方面都應(yīng)該檢查和復(fù)查。
計(jì)算機(jī)是一種工具,它能夠幫助機(jī)械設(shè)計(jì)師減輕繁瑣的計(jì)算,并對(duì)現(xiàn)有數(shù)據(jù)提供進(jìn)一步的分析。互動(dòng)系統(tǒng)基于計(jì)算機(jī)的能力,已經(jīng)使計(jì)算機(jī)輔助設(shè)計(jì)(CAD)和計(jì)算機(jī)輔助制造(CAM)成為了可能。心理學(xué)家經(jīng)常談?wù)撊绾问谷藗冞m應(yīng)他們所操作的機(jī)器。設(shè)計(jì)人員的基本職責(zé)是努力使機(jī)器來(lái)適應(yīng)人們。這并不是一項(xiàng)容易的工作,因?yàn)閷?shí)際上并不存在著一個(gè)對(duì)所有人來(lái)說(shuō)都是最優(yōu)的操作范圍和操作過(guò)程。另一個(gè)重要問(wèn)題,設(shè)計(jì)工程師必須能夠同其他有關(guān)人員進(jìn)行交流和磋商。在開(kāi)始階段設(shè)計(jì)人員必須就初步設(shè)計(jì)同管理人員進(jìn)行交流和磋商,并得到批準(zhǔn)。這一般是通過(guò)口頭討論,草圖和文字材料進(jìn)行的。
如前所訴,機(jī)械設(shè)計(jì)的目的是生產(chǎn)能夠滿足人類需求的產(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)。
新設(shè)計(jì)本身會(huì)有許多缺陷和未能預(yù)料的問(wèn)題發(fā)生,只有當(dāng)這些缺陷和問(wèn)題被解決之后,才能體現(xiàn)出新產(chǎn)品的優(yōu)越性。因此,一個(gè)性能優(yōu)越的產(chǎn)品誕生的同時(shí),也伴隨著較高的風(fēng)險(xiǎn)。應(yīng)該強(qiáng)調(diào)的是,如果設(shè)計(jì)本身不要求采用全新的方法,就沒(méi)有必要僅僅為了變革的目的而采用新方法。