《畢業(yè)論文-空氣壓縮機(jī)V帶校核和噪聲處理設(shè)計(jì)（送全套CAD圖紙 資料打包）》由會(huì)員分享，可在線閱讀，更多相關(guān)《畢業(yè)論文-空氣壓縮機(jī)V帶校核和噪聲處理設(shè)計(jì)（送全套CAD圖紙 資料打包）（35頁(yè)珍藏版）》請(qǐng)?jiān)谘b配圖網(wǎng)上搜索。

下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763計(jì)算機(jī)輔助設(shè)計(jì)的簡(jiǎn)要?dú)v史買文檔送全套圖紙 扣扣 414951605在我們講述 CAD 的基本理論之前,先說(shuō)說(shuō)他的簡(jiǎn)史是比較合適的。CAD 是計(jì)算機(jī)時(shí)代的產(chǎn)品.它從早期的計(jì)算機(jī)繪圖系統(tǒng)發(fā)展到現(xiàn)在的交互式計(jì)算機(jī)圖形學(xué).兩個(gè)這樣的系統(tǒng)包括:麻省理工學(xué)院的 Sage Project 及Sketchpad。Sage Project 旨在開(kāi)發(fā) CRT 顯示器及操作系統(tǒng). Sketchpad 是在 Sage Project 下發(fā)展起來(lái)的 .CRT 顯示和光筆輸入用于與系統(tǒng)進(jìn)行交互操作.CAD 與初次出現(xiàn)的 NC 和 APT(自動(dòng)編程工具)碰巧同時(shí)出世.后來(lái),X-Y 繪圖儀作為計(jì)算機(jī)繪圖的標(biāo)準(zhǔn)硬拷貝輸出裝置使用,一個(gè)有趣的現(xiàn)象是 X-Y 繪圖儀與 NC 鉆床具有相同的基本機(jī)構(gòu),除了繪圖筆 NC 機(jī)床上的主軸刀具替代之外。開(kāi)始，CAD 系統(tǒng)僅僅是一個(gè)帶有內(nèi)置設(shè)計(jì)符號(hào)的繪圖編輯器，供用戶使用的幾何元素只有直線、圓弧、以及兩者的組合。自由曲線及其曲面的發(fā)展，如昆氏嵌面、貝塞爾嵌面以及 B-樣條曲線，使 CAD 系統(tǒng)可用于復(fù)雜曲線與曲面設(shè)計(jì)。三維 CAD 系統(tǒng)允許設(shè)計(jì)者步入三維設(shè)計(jì)空間。由于一個(gè)三維設(shè)計(jì)模型包含了 NC 刀具路徑編程所需的足夠信息，所以能夠開(kāi)發(fā) CAD 與 NC 之間聯(lián)系的系統(tǒng)。所謂交鑰匙的 CAD/CAM 系統(tǒng)便是根據(jù)這一概念開(kāi)發(fā)的，并從 20世紀(jì) 70 年代至 80 年代流行起來(lái)。20 世紀(jì) 70 年代，三維實(shí)體建模的發(fā)明標(biāo)志著 CAD 一個(gè)新時(shí)代的開(kāi)始。過(guò)去的三維線框模型僅用其邊界來(lái)表達(dá)一個(gè)物體。這在某種意義上是模糊的，一個(gè)簡(jiǎn)單的模型可能有幾種解釋。同時(shí)也無(wú)法獲得一個(gè)模型的體積信息。實(shí)體模型包含完整的信息，因此，它們不僅可用于生成工程圖，而且也可在同一模型上完成工程分析。后來(lái)，開(kāi)發(fā)了許多商業(yè)系統(tǒng)和研究系統(tǒng)。這些系統(tǒng)中相當(dāng)多的是基于 PADL 和 BUILD 系統(tǒng)。盡管它們?cè)诒磉_(dá)上是強(qiáng)有力的，但仍然存在許多缺陷。例如，這種系統(tǒng)要有極強(qiáng)的計(jì)算能力和內(nèi)存需求，非常規(guī)的物體建模方式以及標(biāo)注公差能力的缺乏，這一切已阻礙了 CAD 應(yīng)用。直到 20 世紀(jì)80 年代中期，實(shí)體建模開(kāi)始介入設(shè)計(jì)環(huán)境。今天實(shí)體建模的應(yīng)用如同繪圖和線框模型應(yīng)用一樣普遍。在個(gè)人計(jì)算機(jī)上，CAD 已走向大眾化。這種發(fā)展使 CAD 應(yīng)用面廣并且很經(jīng)濟(jì)。CAD 原本作為一種工具僅被航空和其它主要工業(yè)企業(yè)使用。諸如AutoCAD、VersaCAD、CADKEY 等個(gè)人機(jī) CAD 軟件包的引入，使小型公司乃下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763至個(gè)人可以擁有并使用 CAD 系統(tǒng)。到 1988 年為止已銷售 10 萬(wàn)個(gè)以上的 PC CAD 軟件包。今天，基于個(gè)人計(jì)算機(jī)的實(shí)體建摸的 PC CAD 易于獲得，并且銷售變得更為普及。由于微型計(jì)算機(jī)的迅速發(fā)展使得個(gè)人計(jì)算機(jī)能夠承受實(shí)體模型需要的大量計(jì)算負(fù)荷，所以如今許多實(shí)體模型在 PC 機(jī)上運(yùn)行，并且作為平臺(tái) 已不成為一個(gè)問(wèn)題。隨著標(biāo)準(zhǔn)圖形用戶界面的發(fā)展，CAD 系統(tǒng)可以很容易地從一臺(tái)計(jì)算機(jī)傳送，大多數(shù) CAD 系統(tǒng)都能在不同平臺(tái)上運(yùn)行。在大型計(jì)算機(jī)、工作臺(tái)和基于個(gè)人計(jì)算機(jī)的 CAD 系統(tǒng)之間幾乎沒(méi)有區(qū)別。計(jì)算機(jī)輔助設(shè)計(jì)的結(jié)構(gòu)一個(gè) CAD 系統(tǒng)包含三個(gè)主要部分：（1）硬件 計(jì)算機(jī)及輸入/輸出裝置。（2）操作系統(tǒng)軟件。（3）應(yīng)用軟件 CAD 軟件包。硬件主要用于支持軟件功能。在 CAD 系統(tǒng)中使用著種類繁多的硬件。操作系統(tǒng)軟件是 CAD 應(yīng)用軟件與硬件之間的界面。操作系統(tǒng)軟件管理著硬件運(yùn)行并提供許多諸如創(chuàng)建 和取消操作任務(wù)、控制任務(wù)的進(jìn)程、在任務(wù)間分配硬件資源、提供通向軟件資源，如文件、編輯器、編譯和應(yīng)用程序的通道等基本功能。這不僅對(duì) CAD 軟件很重要，而且對(duì)非 CAD 軟件也很重要。應(yīng)用軟件是 CAD 系統(tǒng)的核心。它由二維和三維建摸、繪圖、工程分析等程序組成。一個(gè) CAD 系統(tǒng)的功能便建立在應(yīng)用軟件中。正是應(yīng)用軟件使一種CAD 軟件包區(qū)別于另一種，通常應(yīng)用軟件是依賴于操作系統(tǒng)的。要把在一個(gè)操作系統(tǒng)上運(yùn)行的 CAD 系統(tǒng)移到另一個(gè)操作系統(tǒng)上，并不像編譯軟件那樣微不足道。因此也必須注意操作系統(tǒng)。計(jì)算機(jī)輔助設(shè)計(jì)計(jì)算機(jī)輔助設(shè)計(jì)給了設(shè)計(jì)者去嘗試幾個(gè)可行的解決方案的能力。通常還需要某些形式的設(shè)計(jì)分析計(jì)算，而為了這一任務(wù)已經(jīng)編寫(xiě)了許多程序。計(jì)算機(jī)為設(shè)計(jì)者對(duì)所建議的各種結(jié)構(gòu)設(shè)計(jì)的分析和為最終設(shè)計(jì)準(zhǔn)備正式繪圖提供了強(qiáng)有力的工具。在二維繪圖領(lǐng)域中，計(jì)算機(jī)方法能夠提供比傳統(tǒng)的紙和筆的方法更有意義、更大成本節(jié)約的優(yōu)點(diǎn)，但是一個(gè) CAD 系統(tǒng)并不僅是一個(gè)電子繪圖板。計(jì)算機(jī)繪圖系統(tǒng)可使設(shè)計(jì)者設(shè)計(jì)出既快又準(zhǔn)確的圖形，并且很容易修改。在涉及到重復(fù)性工作時(shí)，會(huì)戲劇性產(chǎn)生復(fù)制產(chǎn)品，因?yàn)闃?biāo)準(zhǔn)圖形只要一次構(gòu)建成功，就可下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763以從圖庫(kù)中取出。剪切和粘貼技術(shù)作為節(jié)約勞動(dòng)力的輔助工具被使用。當(dāng)幾個(gè)分項(xiàng)目設(shè)計(jì)人員從事同一個(gè)工程時(shí)，要建立中心數(shù)據(jù)庫(kù)，使得由某一個(gè)人繪的細(xì)節(jié)圖可以很容易地合并到其它不同的裝配圖中。中心數(shù)據(jù)庫(kù)也可作為標(biāo)準(zhǔn)參考零件庫(kù)使用。有限元是一項(xiàng)成熟的應(yīng)力分析技術(shù)，它多被土木工程和機(jī)械工程所采用。它由將結(jié)構(gòu)劃分成有限個(gè)的小單元所組成，并計(jì)算每一個(gè)單元之間的作用力。如果被分割的單元足夠小，就能對(duì)一個(gè)結(jié)構(gòu)或?qū)嶓w的內(nèi)部應(yīng)力獲得一個(gè)好的估計(jì)。這些計(jì)算機(jī)設(shè)計(jì)慣用于大型結(jié)構(gòu)物的設(shè)計(jì)，諸如船體、橋梁、飛機(jī)機(jī)身和海面油井平臺(tái)。汽車工業(yè)也使用類似的方法來(lái)設(shè)計(jì)和制造車身。二維繪圖CAD 使多視圖的二維繪圖成為可能，視圖空間可以從微米到米的比例范圍內(nèi)無(wú)限變化。它提供給機(jī)械設(shè)計(jì)師放大的功能，即使在恰當(dāng)配合的裝配零件中最小的零件也能看清楚，設(shè)計(jì)程序甚至能自動(dòng)辨認(rèn) CAD 裝配圖中的潛在問(wèn)題。針對(duì)具有不同特征的零件，如運(yùn)動(dòng)的或靜止的，在顯示時(shí)可以被指定成不同的顏色。為了有利于工程設(shè)計(jì)的變化，可使用帶有自動(dòng)尺寸變化的系統(tǒng)對(duì)零件進(jìn)行尺寸標(biāo)注。三維繪圖隨著三維建模的出現(xiàn)，設(shè)計(jì)者具有了更多的自由度。他們可以生成三維零件圖并且可以無(wú)限制地修改以獲得所需的結(jié)果。通過(guò)有限元分析，應(yīng)力加到計(jì)算機(jī)模型上，并且以圖形化的方式顯示其結(jié)果，在產(chǎn)品物理模型真正產(chǎn)生之前，對(duì)設(shè)計(jì)中的任何內(nèi)在問(wèn)題給設(shè)計(jì)者一個(gè)快速的反饋。三維模型可用線框、曲線或?qū)嶓w方式生成。在線框模型中，直線和圓弧構(gòu)成了模型邊界。結(jié)果是一個(gè)可以從任何位置觀察的三維模型，但仍只是一個(gè)框架形式。創(chuàng)建曲面猶如在骨架上包上皮。一旦這樣生成后，模型就可以被渲染，使得圖形看上去更逼真。曲面模型普遍用于構(gòu)建板金的展開(kāi)和重疊以用于制造。實(shí)體模型是最復(fù)雜的建模層次，并且用于建立實(shí)體模型的程序在一段時(shí)期內(nèi)只用在大型計(jì)算機(jī)上。只有近年來(lái)微型計(jì)算機(jī)才達(dá)到這個(gè)能力水平，也可以運(yùn)行復(fù)雜的算法，生成實(shí)體模型。計(jì)算機(jī)“認(rèn)為”實(shí)體模型是一種具有實(shí)體質(zhì)量的模型，所以它可被“鉆孔” “加工” “焊接” ，好象它是一個(gè)實(shí)際的零件。它能夠由任何材料構(gòu)成并呈現(xiàn)其材料特性，因此，能夠進(jìn)行質(zhì)量計(jì)算。下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763計(jì)算機(jī)輔助繪圖的好處用計(jì)算機(jī)完成繪圖及設(shè)計(jì)任務(wù)的好處是令人難忘的：提高速度、提高準(zhǔn)確性、減少硬拷貝存儲(chǔ)空間及易于恢復(fù)信息、加強(qiáng)信息傳輸能力、改善傳輸質(zhì)量和便于修改。速度工業(yè)用計(jì)算機(jī)能以平均每秒 3300 萬(wàn)次完成一項(xiàng)任務(wù)；更新的計(jì)算機(jī)其速度更快。用計(jì)算機(jī)計(jì)算零件的變形量是一個(gè)重要功績(jī)。當(dāng)理論上的載荷力加到零件上時(shí)、通過(guò)計(jì)算機(jī)進(jìn)行有限元分析或者在監(jiān)視器上顯示一個(gè)城市的整體規(guī)劃時(shí)，這兩者都是既費(fèi)時(shí)又計(jì)算量大的任務(wù)。AutoCAD 軟件可根據(jù)需要多次復(fù)制所需模型的形狀和幾何尺寸，快速自動(dòng)地進(jìn)行剖面填充及尺寸標(biāo)注。準(zhǔn)確AutoCAD 程序依靠操作系統(tǒng)及計(jì)算機(jī)平臺(tái)每點(diǎn)具有 14 位的精度。這在用數(shù)學(xué)計(jì)算諸如一個(gè)圓的線段數(shù)、程序必須圓整線段時(shí)是十分重要的。存儲(chǔ)計(jì)算機(jī)能夠在物理空間中存儲(chǔ)上千幅圖，這空間能夠存儲(chǔ)上百幅手工圖。而且計(jì)算機(jī)能夠很容易地搜索和找到一幅圖，只要操作者擁有正確的文件名。傳輸由于計(jì)算機(jī)的數(shù)據(jù)是以電子形式存儲(chǔ)，它能被送到各種位置。最明顯的位置是監(jiān)視器。計(jì)算機(jī)可以在屏幕上以不同的方式顯示數(shù)據(jù)，如圖形，并能方便地將數(shù)據(jù)轉(zhuǎn)換成可讀圖形。這些數(shù)據(jù)也可被傳送給繪圖機(jī)，打印出常見(jiàn)的圖紙，通過(guò)直接連接到計(jì)算機(jī)輔助制造機(jī)床或由電話線傳到地球的任何地方。你可以不再冒損失或丟失的危險(xiǎn)去郵寄圖紙，現(xiàn)在圖紙可以通過(guò)電信網(wǎng)立即發(fā)送到目的地。下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763A Brief History of?。茫粒腂efore we present the basics of CAD ,it is appropriate to give a brief history . CAD is a product of the computer era. It originated from early computer graphic systems to the development of interactive computer graphics. Two such systems include the Sage Project at the Massachusetts Institute of Technology (MIT) and Sketchpad. The Sage Project was aimed at developing CRT displays and operating systems. Sketchpad was developed under the Sage Project. A CRT display and light pen input were used to interact with the system. This coincidentally happened at about the same time that NC and APT(Automatically Programmed Tool)first appeared. Later, X-Y plotters were used as the standard hard-copy output device for computer graphics. An interesting note is that an X-Y plotter has the same basic structure as a NC drilling machine except that a pen is substituted for the tool on NC spindle.In the beginning, CAD systems were no more than graphics editor with some built-in design symbols. The geometry available to the user was limited to lines, circular arcs, and the combination of the two. The development of free-form curves and surfaces, such as Coon’s patch, Bezier’s patch, and B-spline, enable a CAD system allow to be used for sophisticated curves and surface design. Three-dimensional CAD system allow a designer to move into the third dimension. Because a three-dimensional model contains enough information for NC cutter-path programming, the linkage between CAD and NC can be developed. So called turnkey CAD/CAM systems were developed based on this concept and became popular in the 1970s and 1980s.The 1970s marked the beginning of a new era in CAD-the invention of three-dimensional solid modeling. In the past, three-dimensional, wire-frame models represented an object only by its bounding edges. They are ambiguous in the sense that several interpretations might be possible for a single model. There is also no way to find the volumetric information of a model. Solid models contain complete 下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763information; therefore, not only can they be used to produce engineering drawing, but engineering analysis can be performed on the same model as well. Later many commercial systems and research systems were developed. Quite a few of these systems were based on the PADL and BUILD systems. Although they are powerful in representation, many deficiencies still exist. For example, such systems have extreme computation and resource (memory) requirements, an unconventional way of modeling object and a lack of tolerance capability have all hindered CAD applications. It was not until the mid-1980s that solid modelers made their way into the design environment. Today, their use is as common as drafting and wire-frame model applications.CAD implementations on personal computers (PCs) have brought CAD to the masses. This development has made CAD available and affordable. CAD originally was a tool used only by aerospace and other major industrial corporation. The introduction of PC CAD packages, such as, AutoCAD, VersaCAD, CADKEY, and so on, has made it possible for small companies and even individuals to own and use CAD systems. By1980, more than 100,000 PC CAD packages had been sold. Today PC-based solid modelers are available and are becoming increasingly popular. Because rapid developments in microcomputers have enabled PCs to carry the heavy computational load necessary for solid modeling, many solid modelers now run on PCs, and the platform has become less of an issue. With the standard graphics user interface (GUI), CAD systems can be ported easily from one computer to another , Most major CAD systems are able to run on a variety of platforms. There is little difference between mainframe, workstation, and PC-based CAD systems.The Architecture of CADA CAD system consists of three major parts:(1)Hardware computer and input/output(I/O)devices.(2)Operating system software.(3)Application software CAD package.Hardware is used to support the software functions. A wide range of hardware is used in CAD systems. The operating system software is the interface between the CAD application software and the hardware. It supervises the operation of the 下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763hardware and provides basics functions such as creating and removing operation tasks, and providing access to software resources such as files, editors, compilers and utility programs. It is important not only for CAD software, but also for non-CAD software.The application software is the heart of a CAD system. It contains of programs that do 2-D and 3-D modeling, drafting, and engineering analysis. The functionality of a CAD system is built into the application software. It is application software that makes one CAD package different form another. Application software is usually operating-system-dependent. To transport a CAD system running in one operating system to another operating system is not as trivial as recompiling the software. Therefore, attention must be given to the operating system as well.Computer Aided DesignComputer aided design gives the designer the ability to experiment with several possible solutions. Usually some forms of design analysis calculations need to be done and many programs have been written for this task. The computer provides the designer with a powerful tool for analyzing proposed designs and for preparing formal drawing of the final design.Two-dimensional drawing is one area in which computer methods can off significant, quantifiable cost advantages over traditional paper and pen methods, but a CAD system is not just an electronic drawing board. Computer drawing systems enable designers to produce fast accurate drawings and easily modify them. Draught productivity rises dramatically when repetitive work is involved, since standard shapes are constructed only once and can be retrieved from a library. Cut and paste techniques are used as labor-saving aids. When several detail drawn by one person can be easily incorporated into different assemble drawing. This central database also serves as a library of standard preferred computers.Finite element is a sophisticated stress analysis technique much used by civil and mechanical engineers. It consists of dividing a structure into small, but finite, components and calculating the force between each element. If the elements are small enough, a good estimate of the internal stresses in a structure or solid body can be obtained. These computer techniques are routinely used in the design of large structure such as ship hulls, bridges, aircraft fuselages and offshore oil rig. The motor 下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763car industry also uses similar methods for design and manufacture of car bodies.Two-dimensional DrawingsCAD makes possible multiview 2D drawing, with an endless possibility of views in range of scales from microns to meters to meters. It gives the mechanical designer the ability to magnify even the smallest of components to ascertain if the assembled components fit properly and even to design programs to identify automatically potential problems in CAD assembly. Parts with different characteristics, such as movable or stationary, can be assigned different colors on the display. Parts can be dimensioned with automatic dimensioning changes, allowing for expedient engineering design changes.Three-Dimensional DrawingsDesigners have even more freedom with the advent of 3D modeling. They can 3D parts and manipulate them in endless variations to achieve the desired results. Through finite element analysis FEA), stress can be applied to a computer model and the results graphically displayed, giving the designer guick feedback on any inherent problems in a design before the creation of a physical prototype.3Dmodels can be created in wire-frame, in surfaces or in solid form. In wire-frame, lines and arcs form edges that generate the model. The result is a 3D form that can be viewed from any location but still only a skeletal form. Creating a surface stretches a skin over the skeleton (Fig.8-1b).Once this is done, the model can be rendered so that it appears more tangible. Surface models are commonly used in the creation of sheet metal developments that can be unfolded for manufacture.Solid models are the most complex level of modeling and while the programs to create them have been available for some time on large mainframe computers, it is only recently that microcomputers have reached a level of power that allows the running of the sophisticated algorithms needed to create solid model（Fig.8-2）. The computer “thinks” the solid is sold mass so it can be “drilled”, “machined,”or “welded” as if it were an actual physical part. It can be made out of any material’s characteristics, thereby allowing calculations of mass to be made.CAD’S BenefitsThe benefits of computer use in drafting and design tasks are impressive: 下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763increased speed, greater accuracy, reduction of hardcopy storage space as well as better recall, enhanced communication capabilities, improve quality and easier modification.Speed A person computer used in industry can perform a task at an average rate of 33 million operations per second; newer computer are even faster. This is an important feat when using it to calculate the amount of deflection of a component, when theoretical physical forces are applied to it, through finite element analysis(FEA) or when displaying an entire city plan on a monitor, both of which are time-consuming and calculation-intensive tasks. AutoCAD software can duplicate any geometry as many times as required and can also perform crosshatching and dimensioning automatically and equally as fast.AccuracyThe AutoCAD program has an accuracy of 14 significant digits of precision for each point, depending on the operating system and computer platform. This extremely important when the program must round off numbers during mathematical calculations such as segmenting a circle.StorageThe computer can store thousands of drawings in the physical space that it would take to store hundreds of manual drawings. Also, the computer can search and find a drawing with ease, as long as the operator possesses the correct.Communication Because the computer’s data is stored in an electronic form, it cam be sent to s variety of locations. The first obvious location is the monitor. The computer can display the data on the screen in different forms such as graphics, easily converting the data into readable drawing. The data can also be a plotter to produce the familiar paper drawing, via a direct link to a computer-aided manufacturing (CAD) machine or via telephone to anywhere around the globe. You no longer have to mail drawing, risking damage and loss; they can not be at their destination instantly via the telecommunications network.下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763課題研究擬采用的手段和工作路線]課程設(shè)計(jì)方法：1) 獨(dú)立思考，繼承和創(chuàng)新設(shè)計(jì)時(shí)，要認(rèn)真閱讀參考資料，繼承或借鑒前人的設(shè)計(jì)經(jīng)驗(yàn)和成果，但不地進(jìn)行改進(jìn)和創(chuàng)新。能盲目地全盤抄襲，應(yīng)根據(jù)具體的設(shè)計(jì)條件和要求，大膽2) 全面考慮 機(jī)械零部件地強(qiáng)度、剛度、工藝性、經(jīng)濟(jì)性和維護(hù)等要求任何零部件的機(jī)構(gòu)和尺寸，除去考慮它的強(qiáng)度剛度外，還應(yīng)該綜合考慮零件本身及整個(gè)部件的工藝性要求、經(jīng)濟(jì)性要求等才能確定。3) 設(shè)計(jì)方法通過(guò)計(jì)算確定零件的基本尺寸，再通過(guò)草圖設(shè)計(jì)決定其具體結(jié)構(gòu)和尺寸；而有些零件則需先經(jīng)初算和繪草圖，得出初步符合設(shè)計(jì)條件的基本結(jié)構(gòu)尺寸，然后再進(jìn)行必要得計(jì)算，根據(jù)計(jì)算的結(jié)果，再對(duì)結(jié)構(gòu)和尺寸進(jìn)行修改。4) 使用標(biāo)準(zhǔn)和規(guī)范設(shè)計(jì)時(shí)應(yīng)盡量使用標(biāo)準(zhǔn)和規(guī)范，這有利于零件的互換性和工藝性，同時(shí)也可減少設(shè)計(jì)工作量、節(jié)省設(shè)計(jì)時(shí)間，對(duì)于國(guó)家標(biāo)準(zhǔn)或部門規(guī)范，一般都要嚴(yán)格遵守和執(zhí)行。設(shè)計(jì)中采用標(biāo)準(zhǔn)或規(guī)范的多少，時(shí)評(píng)價(jià)設(shè)計(jì)質(zhì)量的一項(xiàng)指標(biāo)。因此，課程設(shè)計(jì)中，凡是有標(biāo)準(zhǔn)或規(guī)范的，應(yīng)該盡量采用工作路線：1) 設(shè)計(jì)準(zhǔn)備了解設(shè)計(jì)任務(wù)書(shū)，明確設(shè)計(jì)要求、工作條件、設(shè)計(jì)內(nèi)容的步驟；通過(guò)查閱有關(guān)設(shè)計(jì)資料，觀看電教片和參觀實(shí)物或模型等，了解設(shè)計(jì)對(duì)象的性能、結(jié)構(gòu)及工藝性；準(zhǔn)備好設(shè)計(jì)需要資料、繪圖工具；擬定設(shè)計(jì)計(jì)劃等。2) 校核 V 帶及減小噪音的措施擬定和確定工作方案；選擇電機(jī)；校核 V 帶。大致分析壓縮機(jī)產(chǎn)生噪聲的原因和有效減小噪聲的措施。3) 工作原理草圖設(shè)計(jì)繪制工作原理草圖；進(jìn)行各零部件和結(jié)構(gòu)件設(shè)計(jì)。4) 繪制零件工作圖繪出零件的必要視圖；標(biāo)注尺寸、公差及表面粗糙度；編寫(xiě)技術(shù)要求和標(biāo)題欄等5) 編寫(xiě)設(shè)計(jì)說(shuō)明書(shū)寫(xiě)明整個(gè)設(shè)計(jì)的主要計(jì)算和一些技術(shù)說(shuō)明。下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763第一章. 引 言目前，容積式壓縮機(jī)的全球年產(chǎn)量為 1.5 億余臺(tái)，其中大多數(shù)被應(yīng)用于空氣動(dòng)力和制冷系統(tǒng)。過(guò)去的 30 年間，轉(zhuǎn)子型線的改進(jìn)使螺桿壓縮機(jī)內(nèi)部泄漏徹底減少，同時(shí)技術(shù)日益成熟的機(jī)床可以將形狀較為復(fù)雜零件的加工公差控制在工程允許的 3μm 以內(nèi)，以致傳統(tǒng)的往復(fù)式壓縮機(jī)在許多應(yīng)用領(lǐng)域逐步被螺桿壓縮機(jī)所替代。人工分析計(jì)算的方法是設(shè)計(jì)者預(yù)測(cè)壓縮機(jī)性能的主要手段，并且在此過(guò)程中取得了一些技術(shù)上的突破，但其適用范圍和準(zhǔn)確度與現(xiàn)代數(shù)控機(jī)床和裝配過(guò)程相比卻遜色很多。因此，先進(jìn)的分析手段增大了技術(shù)創(chuàng)新的可能性，進(jìn)而提高螺桿壓縮機(jī)的性能，降低制造成本，進(jìn)一步擴(kuò)大螺桿壓縮機(jī)的應(yīng)用范圍。轉(zhuǎn)子型線的改進(jìn)依然是提高螺桿壓縮機(jī)性能最有效的手段，依靠經(jīng)驗(yàn)確定轉(zhuǎn)子齒型和轉(zhuǎn)子大量采用通用型線的歷史將被逐步完善的先進(jìn)、合理、高效的轉(zhuǎn)子加工工序所改寫(xiě)，從而取得良好的應(yīng)用成效。另外，改善的壓縮機(jī)內(nèi)部流動(dòng)模型有助于更好地進(jìn)行孔口設(shè)計(jì)，軸承負(fù)荷及其脈動(dòng)的準(zhǔn)確判定有助于選擇更為合適的軸承。最后，如果可以較為準(zhǔn)確地估計(jì)由于壓縮機(jī)內(nèi)部溫度及壓力變化引起的轉(zhuǎn)子和機(jī)殼的扭轉(zhuǎn)變形，我們就可以在機(jī)器的加工過(guò)程中采取相應(yīng)的措施以便將溫度及壓力脈動(dòng)的不良影響降至最小。本文涵蓋了可能引發(fā)螺桿壓縮機(jī)技術(shù)創(chuàng)新的最新流動(dòng)模型與分析方法，以及利用這些手段提高機(jī)器性能、擴(kuò)展應(yīng)用范圍的典型案例。下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763第二章 螺桿壓縮機(jī)的介紹一. 發(fā)展歷程20 世紀(jì) 30 年代，瑞典工程師 Alf Lysholm 在對(duì)燃?xì)廨啓C(jī)進(jìn)行研究時(shí)，希望找到一種作回轉(zhuǎn)運(yùn)動(dòng)的壓縮機(jī)，要求其轉(zhuǎn)速比活塞壓縮機(jī)高得多，以便可由燃?xì)廨啓C(jī)直接驅(qū)動(dòng)，并且不會(huì)發(fā)生喘振。為了達(dá)到上述目標(biāo)，他發(fā)明了螺桿壓縮機(jī)。在理論上，螺桿壓縮機(jī)具有他所需要的特點(diǎn)，但由于必須具有非常大的排氣量，才能滿足燃?xì)廨啓C(jī)工作的要求，螺桿壓縮機(jī)并沒(méi)有在此領(lǐng)域獲得應(yīng)用。盡管如此，Alf Lysholm 及其所在的瑞典 SRM 公司，對(duì)螺桿壓縮機(jī)在其它領(lǐng)域的應(yīng)用，繼續(xù)進(jìn)行了深入的研究。1937 年，Alf Lysholm 在 SRM 公司研制成功了兩類螺桿壓縮機(jī)試驗(yàn)樣機(jī)，并取得了令人滿意的測(cè)試結(jié)果。1946 年，位于蘇格蘭的英國(guó) James Howden 公司，第一個(gè)從瑞典 SRM 公司獲得了生產(chǎn)螺桿壓縮機(jī)的許可證。隨后，歐洲、美國(guó)和日本的多家公司也陸續(xù)從瑞典 SRM 公司獲得了這種許可證，從事螺桿壓縮機(jī)的生產(chǎn)和銷售。最先發(fā)展起來(lái)的螺桿壓縮機(jī)是無(wú)油螺桿壓縮機(jī)。1957 年噴油螺桿空氣壓縮機(jī)投入了市場(chǎng)應(yīng)用。1961 年又研制成功了噴油螺桿制冷壓縮機(jī)和螺桿工藝壓縮機(jī)。過(guò)隨后持續(xù)的基礎(chǔ)理論研究和產(chǎn)品開(kāi)發(fā)試驗(yàn)，通過(guò)對(duì)轉(zhuǎn)子型線的不斷改進(jìn)和專用轉(zhuǎn)子加工設(shè)備的開(kāi)發(fā)成功，螺桿壓縮機(jī)的優(yōu)越性能得到了不斷的發(fā)揮。二. 發(fā)展方向螺桿壓縮機(jī)廣泛應(yīng)用于礦山、化工、動(dòng)力、冶金、建筑、機(jī)械、制冷等工業(yè)部門，在寬廣的容量和式?jīng)r范圍內(nèi)，逐步替代了其它種類的壓縮機(jī)，統(tǒng)計(jì)數(shù)據(jù)表明，螺桿壓縮機(jī)的銷售量已占其它容積式壓縮機(jī)銷售量的 80%以上，在所有正在運(yùn)行的容積式壓縮機(jī)中，有 50%的是螺桿壓縮機(jī)。今后螺桿壓縮機(jī)的市場(chǎng)份額仍將不斷的擴(kuò)大。為了進(jìn)一步改善螺桿壓縮機(jī)的性能，擴(kuò)大其應(yīng)用范圍，應(yīng)在以下幾個(gè)方面作深入研究。下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 13041397631、 在型線嚙合特性、轉(zhuǎn)子受力變形和受熱膨脹等方面研究的基礎(chǔ)上，創(chuàng)造新的高效型線，以進(jìn)一步提高螺桿壓縮機(jī)的效率。2、 分析噴油對(duì)、螺桿壓縮機(jī)工作過(guò)程中泄漏、換熱和摩擦等方面的影響機(jī)理，使噴油參數(shù)的設(shè)計(jì)從目前的經(jīng)驗(yàn)設(shè)計(jì)提高到機(jī)理設(shè)計(jì)和優(yōu)化設(shè)計(jì)。3、 研究吸氣和排氣過(guò)程的流動(dòng)特性，在流場(chǎng)分析的基礎(chǔ)上，進(jìn)一步合理配置吸排氣孔口和相關(guān)連接管道。4、 分析螺壓縮機(jī)的噪音產(chǎn)生機(jī)理，研究型線設(shè)計(jì)和孔口配置等因素對(duì)噪聲指標(biāo)的影響，從而更有效的降低噪聲。5、 研究轉(zhuǎn)子螺旋齒面的加工工藝，除研究高精度和同生產(chǎn)率的專用設(shè)備外，還要研究新型少切削和無(wú)切削工藝。6、 擴(kuò)大螺桿壓縮機(jī)的參數(shù)范圍，主要應(yīng)向小容積流量、高排氣壓力方向發(fā)展。同時(shí)，研究氣量調(diào)節(jié)機(jī)構(gòu)與智能控制系統(tǒng)，提高調(diào)節(jié)式?jīng)r下壓縮機(jī)運(yùn)轉(zhuǎn)的經(jīng)濟(jì)性，進(jìn)一步擴(kuò)大螺桿壓縮機(jī)的應(yīng)用范圍。三. 螺桿壓縮機(jī)的研究意義壓縮機(jī)可分二大類，容積式壓縮機(jī)和動(dòng)力式壓縮機(jī)。容積式壓縮機(jī)又可分往復(fù)式和回轉(zhuǎn)式。本可題研究的是螺桿空氣壓縮機(jī)，屬于雙軸壓縮機(jī)。螺桿壓縮機(jī)-- 是回轉(zhuǎn)容積式壓縮機(jī)，在其中兩個(gè)帶有螺旋型齒輪的轉(zhuǎn)子相互嚙合，從而將氣體壓縮并排出。用可靠性高的螺桿式壓縮機(jī)取代易損件多，可靠性差的活塞式壓縮機(jī)，已經(jīng)成為必然趨勢(shì)。日本螺桿壓縮機(jī) 1976 年僅占 27%，1985 年則上升到 85%。目前西方發(fā)達(dá)國(guó)家螺桿壓縮機(jī)市場(chǎng)占有率為 80%，并保持上升勢(shì)頭。螺桿壓縮機(jī)具有結(jié)構(gòu)簡(jiǎn)單、體積小、沒(méi)有易損件、工作可靠、壽命長(zhǎng)、維修簡(jiǎn)單等優(yōu)點(diǎn)。螺桿壓縮機(jī)有雙螺桿與單螺桿兩種。單螺桿壓縮機(jī)的發(fā)明比雙螺桿壓縮機(jī)晚十幾年，設(shè)計(jì)上更趨合理、先進(jìn)。單螺桿壓縮機(jī)克服了雙螺桿壓縮機(jī)不平衡、軸承易損的缺點(diǎn)；具有壽命長(zhǎng)，噪音低，更加節(jié)能等優(yōu)點(diǎn)。相對(duì)其他復(fù)雜回轉(zhuǎn)機(jī)械來(lái)說(shuō)，螺桿壓縮機(jī)的設(shè)計(jì)制造還是比較簡(jiǎn)單的。由于螺桿壓縮機(jī)的回轉(zhuǎn)運(yùn)動(dòng)部件只有兩個(gè)轉(zhuǎn)子，所以它可以可靠地高速運(yùn)轉(zhuǎn)。高精度的轉(zhuǎn)子齒型銑削與磨削加工可以較低的成本將齒間間隙控制在 30～503μm下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763之間。與早期的機(jī)器相比，內(nèi)部泄漏已經(jīng)大幅減少。可見(jiàn)，螺桿壓縮機(jī)已經(jīng)成為精密、高效的 機(jī)械，并且能夠適用于較大的壓力與排量范圍。因此，容積式壓縮機(jī)的大部分市場(chǎng)與應(yīng)用場(chǎng)合已被螺桿壓縮機(jī)占據(jù)。螺桿壓縮機(jī)的發(fā)展趨勢(shì)是在滿足性能要求的前提下，減小機(jī)器的尺寸。這就意味著需要在保持較高效率的同時(shí)盡可能提高轉(zhuǎn)子齒頂速度。在一般的實(shí)驗(yàn)中，廣泛采用的軸承是滾動(dòng)軸承，因?yàn)榕c滑動(dòng)軸承相比，滾動(dòng)軸承允許更小的間隙。另外，為使吸氣與排氣孔口處的氣流速度降到最低，吸排氣孔口需要開(kāi)設(shè)得盡可能大。上述這些設(shè)計(jì)原則在任何應(yīng)用場(chǎng)合中都是普遍適用的。與先進(jìn)的轉(zhuǎn)子型線一樣，為了取得螺桿壓縮機(jī)設(shè)計(jì)的最大進(jìn)步，能夠?qū)p失降到最低的其他組件的改進(jìn)也是非常重要的。所以，對(duì)轉(zhuǎn)子與機(jī)殼之間的間隙進(jìn)行合理選擇也是很有必要的，尤其是在高壓端。當(dāng)間隙較小時(shí)，需要采用較昂貴的優(yōu)質(zhì)軸承，當(dāng)通過(guò)預(yù)緊將間隙控制在允許范圍內(nèi)時(shí)，可以采用比較廉價(jià)的軸承。 螺桿壓縮機(jī)尤其是噴油螺桿壓縮機(jī)通常在較高壓力差下工作，單級(jí)壓比較高，產(chǎn)生的軸向力與徑向力較大。中小型 壓縮機(jī)一般采用滾動(dòng)軸承。由于轉(zhuǎn)子中心距受其一定的影響，為設(shè)計(jì)出滿意的產(chǎn)品，滾動(dòng)軸承的選用及校核也應(yīng)慎重。值得一提的是，近期研發(fā)出的一種摩擦很小的滾動(dòng)軸承提供了一個(gè)不錯(cuò)的選擇，詳細(xì)參見(jiàn) Meyers[37]。通常在轉(zhuǎn)子的高壓端設(shè)有兩個(gè)軸承來(lái)分別承受軸向力與徑向力。轉(zhuǎn)子間的接觸力大小取決于它們之間傳遞的扭矩，當(dāng)陰陽(yáng)轉(zhuǎn)子直接接觸時(shí)，接觸力較大。當(dāng)壓縮機(jī)的驅(qū)動(dòng)力矩由陽(yáng)轉(zhuǎn)子傳送時(shí)，接觸力相對(duì)較小。倘若將驅(qū)動(dòng)力矩由陰轉(zhuǎn)子傳送，產(chǎn)生的接觸力非常大，這是不允許的。噴入壓縮機(jī)內(nèi)的潤(rùn)滑油也有潤(rùn)滑軸承的作用，但是為了盡量減小摩擦損失，軸承的供油與回油系統(tǒng)是獨(dú)立的。機(jī)體上的噴油孔口開(kāi)設(shè)在由熱力計(jì)算結(jié)果得出的氣體溫度與潤(rùn)滑油溫度相等的位置，除此之外，噴油孔口應(yīng)位于轉(zhuǎn)子螺旋線上方，這樣，潤(rùn)滑油可以從陰轉(zhuǎn)子齒頂沿螺旋齒面切線方向進(jìn)入機(jī)體，達(dá)到回收所噴入潤(rùn)滑油的動(dòng)能的目的。為將吸排氣孔口的流動(dòng)損失降到最低，螺桿壓縮機(jī)還應(yīng)符合以下技術(shù)指標(biāo)。進(jìn)入壓縮機(jī)的氣體的流道應(yīng)盡量避免彎曲，這就要求吸氣孔口要開(kāi)設(shè)在機(jī)殼上，另外，盡量擴(kuò)大進(jìn)氣的流通面積從而降低吸氣孔口處的氣體流速。排下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763氣孔口的尺寸主要是由熱力性能所要求的內(nèi)壓力比決定的，還應(yīng)考慮降低排氣流速和降低內(nèi)部、排氣孔口處流動(dòng)損失的需要。機(jī)殼的設(shè)計(jì)加工要盡量減小其重量，還應(yīng)配置加強(qiáng)筋以提高高壓下的強(qiáng)度。雖然螺桿壓縮機(jī)現(xiàn)在已經(jīng)是一種發(fā)展比較成熟的產(chǎn)品，但由于以計(jì)算機(jī)建模與數(shù)值分析為主的工程科學(xué)的介入，我們還可以在設(shè)計(jì)過(guò)程中做出更大的改進(jìn)，提高效率、減小機(jī)器尺寸、降低制造成本等。另外，為了達(dá)到最優(yōu)化的設(shè)計(jì)，軸承技術(shù)與潤(rùn)滑的改善也是十分重要的.下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或1304139763下載論文就送你全套 CAD 圖紙，Q 咨詢 414951605 或 1304139763四.螺桿式空壓機(jī)原理1.吸氣過(guò)程： 螺桿式的進(jìn)氣側(cè)吸氣口，必須設(shè)計(jì)得使壓縮室可以充分吸氣，而螺桿式壓縮機(jī)并無(wú)進(jìn)氣與排氣閥組，進(jìn)氣只靠一調(diào)節(jié)閥的開(kāi)啟、關(guān)閉調(diào)節(jié)，當(dāng)轉(zhuǎn)子轉(zhuǎn)動(dòng)時(shí)，主副轉(zhuǎn)子的齒溝空間在轉(zhuǎn)至進(jìn)氣端壁開(kāi)口時(shí)，其空間最大，此時(shí)轉(zhuǎn)子的齒溝空間與進(jìn)氣口之自由空氣相通，因在排氣時(shí)齒溝之空氣被全數(shù)排出，排氣結(jié)束時(shí)，齒溝乃處于真空狀態(tài)，當(dāng)轉(zhuǎn)到進(jìn)氣口時(shí)，外界空氣即被吸入，沿軸向流入主副轉(zhuǎn)子的齒溝內(nèi)。當(dāng)空氣充滿整個(gè)齒溝時(shí)，轉(zhuǎn)子之進(jìn)氣側(cè)端面轉(zhuǎn)離了機(jī)殼之進(jìn)氣口，在齒溝間的空氣即被封閉。 2、封閉及輸送過(guò)程： 主副兩轉(zhuǎn)子在吸氣結(jié)束時(shí)，其主副轉(zhuǎn)子齒峰會(huì)與機(jī)殼閉封，此時(shí)空氣在齒溝內(nèi)閉封不再外流，即[封閉過(guò)程]。兩轉(zhuǎn)子繼續(xù)轉(zhuǎn)動(dòng)，其齒峰與