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編號
無錫太湖學院
畢業(yè)設計（論文）
相關資料
題目：車門玻璃升降器的設計及運動仿真
信機 系 機械工程及自動化專業(yè)
學 號： 0623005
學生姓名： 黃宇流
指導教師： 林承德 （職稱：教 授 ）
（職稱： ）
2013年5月25日
目 錄
一、畢業(yè)設計（論文）開題報告
二、畢業(yè)設計（論文）外文資料翻譯及原文
三、學生“畢業(yè)論文（論文）計劃、進度、檢查及落實表”
四、實習鑒定表
無錫太湖學院
畢業(yè)設計（論文）
開題報告
題目：車門玻璃升降器的設計及運動仿真
信機 系 機械工程及自動化 專業(yè)
學 號： 0923056
學生姓名： 黃宇流
指導教師： 林承德 （職稱：教 授 ）
（職稱： ）
2012年11月27日
課題來源
江蘇省蘇州奧杰汽車技術有限公司
科學依據(jù)（包括課題的科學意義；國內(nèi)外研究概況、水平和發(fā)展趨勢；應用前景等）
（1）課題科學意義
正在開發(fā)中的某車型的滑門需要一款玻璃升降器作為車門附件，用來控制滑門車窗的開啟和關閉。本課題主要著重負責玻璃升降器的逆向設計，運用UG軟件建立玻璃升降器的三維數(shù)模，通過運動仿真模塊校核玻璃升降器在滑門上的布置和干涉情況，從而優(yōu)化結構，方便汽車配件廠盡快實現(xiàn)數(shù)控加工，加快汽車新產(chǎn)品上市。我國電動玻璃升降器的發(fā)展很快，它不但在轎車中大量配套，而且開始在輕型客車中大量配套。目前國內(nèi)外很多主機廠和汽車配件廠實現(xiàn)了基于原有設計平臺的逆向設計，加快了產(chǎn)品開發(fā)的過程，將來將會實現(xiàn)產(chǎn)品系列參數(shù)化設計，只需對三維數(shù)模某些結構尺寸修改參數(shù)，就能實現(xiàn)產(chǎn)品的快速開發(fā)。隨著汽車工業(yè)的發(fā)展，電動玻璃升降器將呈現(xiàn)智能化、模塊化的發(fā)展趨勢。
研究內(nèi)容
一．玻璃升降器設計部分：
1．適合該車型的玻璃升降器方案選擇；
2．逆向設計玻璃升降器的機械結構。
二．玻璃升降器的運動仿真
三．玻璃升降器運動校核部分：
1．運動行程校核；
2. 傳動動力校核；
3．結構干涉校核。
擬采取的研究方法、技術路線、實驗方案及可行性分析
分析國內(nèi)外電動玻璃升降器市場各種電動玻璃升降器的特點以及適應性、電動玻璃升降器開發(fā)中的問題、各種電機性能、各部件機構及工作原理、機械設計過程，通過對升降器各部件的性能分析，最終開發(fā)出一款適合該車型的電動玻璃升降器。
運用UG軟件進行逆向設計，分析玻璃升降器總成及各部件的位置結構和功能，建立三維數(shù)模，對總成進行運動仿真，分析運動數(shù)據(jù)，優(yōu)化結構布置。
江蘇省蘇州奧杰汽車技術有限公司在汽車設計領域，運用 當今汽車工業(yè)最先進的計算機輔助造型(CAS)、計算機輔助工程(CAE)、計算機輔助設計(CAD)和計算機輔助制造(CAM)軟件進行設計開發(fā)，至今已積累了數(shù)十個車型，整車平臺及零部件開發(fā)經(jīng)驗。在玻璃升降器方面具備很強的設計開發(fā)能力，同時國內(nèi)外市場對電動玻璃升降器的需求不斷擴大，對電動玻璃升降器的智能化、模塊化越來越高，具備很大的市場可行性。
研究計劃及預期成果
研究計劃：
2012年11月12日-2012年12月25日：按照任務書要求查閱論文相關參考資料，填寫畢業(yè)設計開題報告書。
2013年1月11日-2013年3月5日：填寫畢業(yè)實習報告。
2013年3月8日-2013年3月14日：按照要求修改畢業(yè)設計開題報告。
2013年3月15日-2013年3月21日：學習并翻譯一篇與畢業(yè)設計相關的英文材料。
2013年3月22日-2013年4月11日：CAD繪圖。
2013年4月12日-2013年4月25日：UG設計。
2013年4月26日-2013年5月21日：畢業(yè)論文撰寫和修改工作。
預期成果：
達到預期的實驗結論：使用CAD設計繪制車門玻璃升降器裝配圖，并用UG繪制三維圖像，制作PPT文件，以及仿真。
特色或創(chuàng)新之處
玻璃升降器的整個機構、功能、性能都可通過UG逆向設計得以實現(xiàn)，實現(xiàn)了產(chǎn)品的快速設計；通過運動仿真可以校核是否存在結構干涉情況，降低了樣品試制的成本和風險。
交叉臂式電動玻璃升降器 適用負載較大車門玻璃，結構簡單，制造成本低，使用壽命長，采用高防護電機驅動，實現(xiàn)車門玻璃的自動升降，乘員操作方便靈活，提高了車型的整體舒適度和豪華感。
已具備的條件和尚需解決的問題
已具備的條件：電腦；相關開發(fā)軟件；部分技術資料。
尚需解決的問題：學習UG軟件；確定產(chǎn)品的結構尺寸和技術要求；逆向設計建立三維數(shù)模；總成運動仿真校核。
指導教師意見
指導教師簽名：
年 月 日
教研室（學科組、研究所）意見
教研室主任簽名：
年 月 日
系意見
主管領導簽名：
年 月 日
英文原文
Machine design theory
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, engineerig 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
1 Lathes
Lathes are machine tools designed primarily to do turning, facing and boring, Very little turning is done on other types of machine tools, and none can do it with equal facility. Because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single setup of the work piece. Consequently, more lathes of various types are used in manufacturing than any other machine tool.
The essential components of a lathe are the bed, headstock assembly, tailstock assembly, and the leads crew and feed rod.
The bed is the backbone of a lathe. It usually is made of well normalized or aged gray or nodular cast iron and provides s heavy, rigid frame on which all the other basic components are mounted. Two sets of parallel, longitudinal ways, inner and outer, are contained on the bed, usually on the upper side. Some makers use an inverted V-shape for all four ways, whereas others utilize one inverted V and one flat way in one or both sets, They are precision-machined to assure accuracy of alignment. On most modern lathes the way are surface-hardened to resist wear and abrasion, but precaution should be taken in operating a lathe to assure that the ways are not damaged. Any inaccuracy in them usually means that the accuracy of the entire lathe is destroyed.
The headstock is mounted in a foxed position on the inner ways, usually at the left end of the bed. It provides a powered means of rotating the word at various speeds . Essentially, it consists of a hollow spindle, mounted in accurate bearings, and a set of transmission gears-similar to a truck transmission—through which the spindle can be rotated at a number of speeds. Most lathes provide from 8 to 18 speeds, usually in a geometric ratio, and on modern lathes all the speeds can be obtained merely by moving from two to four levers. An increasing trend is to provide a continuously variable speed range through electrical or mechanical drives.
Because the accuracy of a lathe is greatly dependent on the spindle, it is of heavy construction and mounted in heavy bearings, usually preloaded tapered roller or ball types. The spindle has a hole extending through its length, through which long bar stock can be fed. The size of maximum size of bar stock that can be machined when the material must be fed through spindle.
The tailsticd assembly consists, essentially, of three parts. A lower casting fits on the inner ways of the bed and can slide longitudinally thereon, with a means for clamping the entire assembly in any desired location, An upper casting fits on the lower one and can be moved transversely upon it, on some type of keyed ways, to permit aligning the assembly is the tailstock quill. This is a hollow steel cylinder, usually about 51 to 76mm(2to 3 inches) in diameter, that can be moved several inches longitudinally in and out of the upper casting by means of a hand wheel and screw.
The size of a lathe is designated by two dimensions. The first is known as the swing. This is the maximum diameter of work that can be rotated on a lathe. It is approximately twice the distance between the line connecting the lathe centers and the nearest point on the ways, The second size dimension is the maximum distance between centers. The swing thus indicates the maximum work piece diameter that can be turned in the lathe, while the distance between centers indicates the maximum length of work piece that can be mounted between centers.
Engine lathes are the type most frequently used in manufacturing. They are heavy-duty machine tools with all the components described previously and have power drive for all tool movements except on the compound rest. They commonly range in size from 305 to 610 mm(12 to 24 inches)swing and from 610 to 1219 mm(24 to 48 inches) center distances, but swings up to 1270 mm(50 inches) and center distances up to 3658mm(12 feet) are not uncommon. Most have chip pans and a built-in coolant circulating system. Smaller engine lathes-with swings usually not over 330 mm (13 inches ) –also are available in bench type, designed for the bed to be mounted on a bench on a bench or cabinet.
Although engine lathes are versatile and very useful, because of the time required for changing and setting tools and for making measurements on the work piece, thy are not suitable for quantity production. Often the actual chip-production tine is less than 30% of the total cycle time. In addition, a skilled machinist is required for all the operations, and such persons are costly and often in short supply. However, much of the operator’s time is consumed by simple, repetitious adjustments and in watching chips being made. Consequently, to reduce or eliminate the amount of skilled labor that is required, turret lathes, screw machines, and other types of semiautomatic and automatic lathes have been highly developed and are widely used in manufacturing.
2 Numerical Control
One of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC). Prior to the advent of NC, all machine tools ere manually operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools.
Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool. For a machine tool to be numerically controlled, it must be interfaced with a device for accepting and decoding the programmed instructions, known as a reader.
Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines, they can produce parts more uniformly, they are faster, and the long-run tooling costs are lower. The development of NC led to the development of several other innovations in manufacturing technology:Electrical discharge machining,Laser cutting,Electron beam welding.
Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tolls and processes.
Like so many advanced technologies, NC was born in the laboratories of the Massachusetts Institute of Technology. The concept of NC was developed in the early 1950s with funding provided by the U.S. Air Force. In its earliest stages, NC machines were able to made straight cuts efficiently and effectively.
However, curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter the straight lines making up the steps, the smoother is the curve, Each line segment in the steps had to be calculated.
This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language. This is a special programming language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the fur ther development from those used today. The machines had hardwired logic circuits. The instructional programs were written on punched paper, which was later to be replaced by magnetic plastic tape. A tape reader was used to interpret the instructions written on the tape for the machine. Together, all of this represented a giant step forward in the control of machine tools. However, there were a number of problems with NC at this point in its development.
A major problem was the fragility of the punched paper tape medium. It was common for the paper tape containing the programmed instructions to break or tear during a machining process. This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to be rerun through the reader. If it was necessary to produce 100 copies of a given part, it was also necessary to run the paper tape through the reader 100 separate tines. Fragile paper tapes simply could not withstand the rigors of a shop floor environment and this kind of repeated use.
This led to the development of a special magnetic plastic tape. Whereas the paper carried the programmed instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of magnetic dots. The plastic tape was much stronger than the paper tape, which solved the problem of frequent tearing and breakage. However, it still left two other problems.
The most important of these was that it was difficult or impossible to change the instructions entered on the tape. To made even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape through the reader as many times as there were parts to be produced. Fortunately, computer technology became a reality and soon solved the problems of NC associated with punched paper and plastic tape.
The development of a concept known as direct numerical control (DNC) solved the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions. In direct numerical control, machine tools are tied, via a data transmission link, to a host computer. Programs for operating the machine tools are stored in the host computer and fed to the machine tool an needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However, it is subject to the same limitations as all technologies that depend on a host computer. When the host computer goes down, the machine tools also experience downtime. This problem led to the development of computer numerical control.
3 Turning
The engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. Today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered.
The engine lathe has been replaced in today’s production shops by a wide variety of automatic lathes such as automatic of single-point tooling for maximum metal removal, and the use of form tools for finish on a par with the fastest processing equipment on the scene today.
Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. In redesigning an experimental part for production, economical tolerances should be used.
Turret Lathes Production machining equipment must be evaluated now, more than ever before, this criterion for establishing the production qualification of a specific method, the turret lathe merits a high rating.
In designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turrets lathe, the designer should strive for a minimum of operations.
中文譯文
機械設計理論
機械設計是一門通過設計新產(chǎn)品或者改進老產(chǎn)品來滿足人類需求的應用技術科學。它涉及工程技術的各個領域，主要研究產(chǎn)品的尺寸、形狀和詳細結構的基本構思，還要研究產(chǎn)品在制造、銷售和使用等方面的問題。
進行各種機械設計工作的人員通常被稱為設計人員或者機械設計工程師。機械設計是一項創(chuàng)造性的工作。設計工程師不僅在工作上要有創(chuàng)造性，還必須在機械制圖、運動學、工程材料、材料力學和機械制造工藝學等方面具有深厚的基礎知識。
如前所訴，機械設計的目的是生產(chǎn)能夠滿足人類需求的產(chǎn)品。發(fā)明、發(fā)現(xiàn)和科技知識本身并不一定能給人類帶來好處，只有當它們被應用在產(chǎn)品上才能產(chǎn)生效益。因而，應該認識到在一個特定的產(chǎn)品進行設計之前，必須先確定人們是否需要這種產(chǎn)品
1.車床
車床主要是為了進行車外圓、車端面和鏜孔等項工作而設計的機床。車削很少在其他種類的機床上進行，而且任何一種其他機床都不能像車床那樣方便地進行車削加工。由于車床還可以用來鉆孔和鉸孔，車床的多功能性可以使工件在一次安裝中完成幾種加工。因此，在生產(chǎn)中使用的各種車床比任何其他種類的機床都多。
車床的基本部件有：床身、主軸箱組件、尾座組件、溜板組件、絲杠和光杠。
床身是車床的基礎件。它能常是由經(jīng)過充分正火或時效處理的灰鑄鐵或者球墨鐵制成。它是一個堅固的剛性框架，所有其他基本部件都安裝在床身上。通常在床身上有內(nèi)外兩組平行的導軌。有些制造廠對全部四條導軌都采用導軌尖朝上的三角形導軌（即山形導軌），而有的制造廠則在一組中或者兩組中都采用一個三角形導軌和一個矩形導軌。導軌要經(jīng)過精密加工以保證其直線度精度。為了抵抗磨損和擦傷，大多數(shù)現(xiàn)代機床的導軌是經(jīng)過表面淬硬的，但是在操作時還應該小心，以避免損傷導軌。導軌上的任何誤差，常常意味著整個機床的精度遭到破壞。
主軸箱安裝在內(nèi)側導軌的固定位置上，一般在床身的左端。它提供動力，并可使工件在各種速度下回轉。它基本上由一個安裝在精密軸承中的空心主軸和一系列變速齒輪(類似于卡車變速箱)所組成。通過變速齒輪，主軸可以在許多種轉速下旋轉。大多數(shù)車床有8~12種轉速，一般按等比級數(shù)排列。而且在現(xiàn)代機床上只需扳動2~4個手柄，就能得到全部轉速。一種正在不斷增長的趨勢是通過電氣的或者機械的裝置進行無級變速。
由于機床的精度在很大程度上取決于主軸，因此，主軸的結構尺寸較大，通常安裝在預緊后的重型圓錐滾子軸承或球軸承中。主軸中有一個貫穿全長的通孔，長棒料可以通過該孔送料。主軸孔的大小是車床的一個重要尺寸，因此當工件必須通過主軸孔供料時，它確定了能夠加工的棒料毛坯的最大尺寸。
尾座組件主要由三部分組成。底板與床身的內(nèi)側導軌配合，并可以在導軌上作縱向移動。底板上有一個可以使整個尾座組件夾緊在任意位置上的裝置。尾座體安裝在底板上，可以沿某種類型的鍵槽在底板上橫向移動，使尾座能與主軸箱中的主軸對正。尾座的第三個組成部分是尾座套筒。它是一個直徑通常大約在51~76mm（2~3英寸）之間的鋼制空心圓柱體。通過手輪和螺桿，尾座套筒可以在尾座體中縱向移入和移出幾個英寸。
車床的規(guī)格用兩個尺寸表示。第一個稱為車床的床面上最大加工直徑。這是在車床上能夠旋轉的工件的最大直徑。它大約是兩頂尖連線與導軌上最近點之間距離的兩倍。第二個規(guī)格尺寸是兩頂尖之間的最大距離。車床床面上最大加工直徑表示在車床上能夠車削的最大工件直徑，而兩頂尖之間的最大距離則表示在兩個頂尖之間能夠安裝的工件的最大長度。
普通車床是生產(chǎn)中最經(jīng)常使用的車床種類。它們是具有前面所敘的所有那些部件的重載機床，并且除了小刀架之外，全部刀具的運動都有機動進給。它們的規(guī)格通常是：車床床面上最大加工直徑為305~610mm（12~24英寸）；但是，床面上最大加工直徑達到1270mm（50英寸）和兩頂尖之間距離達到3658mm的車床也并不少見。這些車床大部分都有切屑盤和一個安裝在內(nèi)部的冷卻液循環(huán)系統(tǒng)。小型的普通車床—車床床面最大加工直徑一般不超過330mm（13英寸）--被設計成臺式車床，其床身安裝在工作臺或柜子上。
雖然普通車床有很多用途，是很有用的機床，但是更換和調(diào)整刀具以及測量工件花費很多時間，所以它們不適合在大量生產(chǎn)中應用。通常，它們的實際加工時間少于其總加工時間的30%。此外，需要技術熟練的工人來操作普通車床，這種工人的工資高而且很難雇到。然而，操作工人的大部分時間卻花費在簡單的重復調(diào)整和觀察切屑過程上。因此，為了減少或者完全不雇用這類熟練工人，六角車床、螺紋加工車床和其他類型的半自動和自動車床已經(jīng)很好地研制出來，并已經(jīng)在生產(chǎn)中得到廣泛應用。
2.數(shù)字控制
先進制造技術中的一個基本的概念是數(shù)字控制（NC）。在數(shù)控技術出現(xiàn)之前，所有的機床都是由人工操縱和控制的。在與人工控制的機床有關的很多局限性中，操作者的技能大概是最突出的問題。采用人工控制是，產(chǎn)品的質量直接與操作者的技能有關。數(shù)字控制代表了從人工控制機床走出來的第一步。
數(shù)字控制意味著采用預先錄制的、存儲的符號指令來控制機床和其他制造系統(tǒng)。一個數(shù)控技師的工作不是去操縱機床，而是編寫能夠發(fā)出機床操縱指令的程序。對于一臺數(shù)控機床，其上必須安有一個被稱為閱讀機的界面裝置，用來接受和解譯出編程指令。
發(fā)展數(shù)控技術是為了克服人類操作者的局限性，而且它確實完成了這項工作。數(shù)字控制的機器比人工操縱的機器精度更高、生產(chǎn)出零件的一致性更好、生產(chǎn)速度更快、而且長期的工藝裝備成本更低。數(shù)控技術的發(fā)展導致了制造工藝中其他幾項新發(fā)明的產(chǎn)生：
電火花加工技術、激光切割、電子束焊接
數(shù)字控制還使得機床比它們采用有人工操的前輩們的用途更為廣泛。
一臺數(shù)控機床可以自動生產(chǎn)很多類的零件，每一個零件都可以有不同的和復雜的加工過程。數(shù)控可以使生產(chǎn)廠家承擔那些對于采用人工控制的機床和工藝來說，在經(jīng)濟上是不劃算的產(chǎn)品生產(chǎn)任務。
同許多先進技術一樣，數(shù)控誕生于麻省理工學院的實驗室中。數(shù)控這個概念是50年代初在美國空軍的資助下提出來的。在其最初的價段，數(shù)控機床可以經(jīng)濟和有效地進行直線切割。
然而，曲線軌跡成為機床加工的一個問題，在編程時應該采用一系列的水平與豎直的臺階來生成曲線。構成臺階的每一個線段越短，曲線就越光滑。臺階中的每一個線段都必須經(jīng)過計算。
在這個問題促使下，于1959年誕生了自動編程工具（APT）語言。這是一個專門適用于數(shù)控的編程語言，使用類似于英語的語句來定義零件的幾何形狀，描述切削刀具的形狀和規(guī)定必要的運動。APT語言的研究和發(fā)展是在數(shù)控技術進一步發(fā)展過程中的一大進步。最初的數(shù)控系統(tǒng)下今天應用的數(shù)控系統(tǒng)是有很大差別的。在那時的機床中，只有硬線邏輯電路。指令程序寫在穿孔紙帶上（它后來被塑料帶所取代），采用帶閱讀機將寫在紙帶或磁帶上的指令給機器翻譯出來。所有這些共同構成了機床數(shù)字控制方面的巨大進步。然而，在數(shù)控發(fā)展的這個階段中還存在著許多問題。
一個主要問題是穿孔紙帶的易損壞性。在機械加工過程中，載有編程指令信息的紙帶斷裂和被撕壞是常見的事情。在機床上每加工一個零件，都需要將載有編程指令的紙帶放入閱讀機中重新運行一次。因此，這個問題變得很嚴重。如果需要制造100個某種零件，則應該將紙帶分別通過閱讀機100次。易損壞的紙帶顯然不能承受嚴配的車間環(huán)境和這種重復使用。
這就導致了一種專門的塑料磁帶的研制。在紙帶上通過采用一系列的小孔來載有編程指令，而在塑料帶上通過采用一系列的磁點瞇載有編程指令。塑料帶的強度比紙帶的強度要高很多，這就可以解決常見的撕壞和斷裂問題。然而，它仍然存在著兩個問題。
其中最重要的一個問題是，對輸入到帶中指令進行修改是非常困難的，或者是根本不可能的。即使對指令程序進行最微小的調(diào)整，也必須中斷加工，制作一條新帶。而且?guī)ㄟ^閱讀機的次數(shù)還必須與需要加工的零件的個數(shù)相同。幸運的是，計算機技術的實際應用很快解決了數(shù)控技術中與穿孔紙帶和塑料帶有關的問題。
在形成了直接數(shù)字控制（DNC）這個概念之后，可以不再采用紙帶或塑料帶作為編程指令的載體，這樣就解決了與之有關的問題。在直接數(shù)字控制中，幾臺機床通過數(shù)據(jù)傳輸線路聯(lián)接到一臺主計算機上。操縱這些機床所需要的程序都存儲在這臺主計算機中。當需要時，通過數(shù)據(jù)傳輸線路提供給每臺機床。直接數(shù)字控制是在穿孔紙帶和塑料帶基礎上的一大進步。然而，它敢有著同其他信賴于主計算機技術一樣的局限性。當主計算機出現(xiàn)故障時，由其控制的所有機床都將停止工作。這個問題促使了計算機數(shù)字控制技術的產(chǎn)生。
微處理器的發(fā)展為可編程邏輯控制器和微型計算機的發(fā)展做好了準備。這兩種技術為計算機數(shù)控（CNC）的發(fā)打下了基礎。采用CNC技術后，每臺機床上都有一個可編程邏輯控制器或者微機對其進行數(shù)字控制。這可以使得程序被輸入和存儲在每臺機床內(nèi)部。它還可以在機床以外編制程序，并將其下載到每臺機床中。計算機數(shù)控解決了主計算機發(fā)生故障所帶來的問題，但是它產(chǎn)生了另一個被稱為數(shù)據(jù)管理的問題。同一個程序可能要分別裝入十個相互之間沒有通訊聯(lián)系的微機中。這個問題目前正在解決之中，它是通過采用局部區(qū)域網(wǎng)絡將各個微機聯(lián)接起來，以得于更好地進行數(shù)據(jù)管理。
3.車削加工
普通車床作為最早的金屬切削機床的一種，目前仍然有許多有用的和為人要的特性和為人們所需的特性?，F(xiàn)在，這些機床主要用在規(guī)模較小的工廠中，進行小批量的生產(chǎn)，而不是進行大批量的和產(chǎn)。
在現(xiàn)代的生產(chǎn)車間中，普通車床已經(jīng)被種類繁多的自動車床所取代，諸如自動仿形車床，六角車床和自動螺絲車床?，F(xiàn)在，設計人員已經(jīng)熟知先利用單刃刀具去除大量的金屬余量，然后利用成型刀具獲得表面光潔度和精度這種加工方法的優(yōu)點。這種加工方法的生產(chǎn)速度與現(xiàn)在工廠中使用的最快的加工設備的速度相等。