自動化生產(chǎn)線--外文翻譯

1、<p><b>　　中文3035字</b></p><p>　　English Translation Material</p><p>　　1. Transfer Machine</p><p>　　The highest degree of automation with special-purpose, multifu

2、nction machines is achieved by using transfer machines. Transfer machine are essentially a combination of individual workstations arranged in the required sequence, connected by work transfer devices, and integrated with

3、 interlocked controls. Workplaces are automatically transferred between the stations, which are equipped with horizontal, vertical, or angular units to perform machining , gaging ,workplace repositioning, assembling, &l

4、t;/p><p>　　An important advantage of transfer machines is that they permit the maximum number of operations to be performed simultaneously. There is relatively no limitation on the number of workplace surface o

5、r planes that can be machined, since devices can be interposed in transfer machines at practically any point for inverting, rotating, or orienting the workplace, so as to complete the machining operations. Work repositio

6、ning also minimizes the need for angular machining heads and allows operations to</p><p>　　One or more finished parts are produced on a transfer machine with each index of the transfer system that moves the

7、parts from stations to stations. Production efficiencies of such machines generally range from 50% for a machine variety of different parts to 85% for a machine producing one part, in high production, depending upon the

8、workplace and how the machine is operated(material handling method, maintenance procedures, etc. )</p><p>　　All types of machining operations, such as drilling, tapping, reaming, boring, and milling, are eco

9、nomically combined on transfer machines. Lathe-type operations such as turning and facing are also being performed on in-line transfer machine, with the workplace being rotated in selected</p><p>　　machining

10、 stations. Turning operations are performed in lathe-type segments in which toolholders are fed on slides mounted on tunnel-type bridge units. Workplace are located on centers and rotated by chucks at each turning statio

11、n. Turning stations with CNC are available for use on in-line transfer machine. The CNC units allow the machine cycles to be easily altered to accommodate changes in workplace design and can also be used for automatic to

12、ol adjustments.</p><p>　　Maximum production economy on transfer lines is often achieved by assembling parts to the workplaces during their movement through the machine. such items as bushings, seals, welch p

13、lugs, and heat tubes can be assembled and then machine or tested during the transfer machining sequence. Automatic nut torquing following the application of part subassemblies can also be carried out.</p><p>

14、;　　Gundrilling or reaming on transfer machines is an ideal application provided that proper machining units are employed and good bushing practices are followed. Contour boring and turning of spherical seats and other su

15、rface can be done with tracer-controlled single-point inserts, thus eliminating the need for costly special form tools. In-process gaging of reamed or bored holes and automatic tool setting are done on transfer machines

16、to maintain close tolerances.</p><p>　　Less conventional operations sometimes performed on transfer machines include grinding, induction heating of ring gears for shrink-fit pressing on flywheels, induction

17、hardening of valve seats, deep rolling to apply compressive preloads, and burnishing. </p><p>　　Transfer machines have long been used in the automotive industry for production rates with a minimum of manual

18、part handling. In addition to decreasing labor requirements, such machines ensure consistently uniform, high-quality parts at lower cost. They are no longer confined just to rough machining and now often eliminate the ne

19、ed for subsequent operations such as grinding and honing.</p><p>　　More recently, there has been an increasing demand for transfer machines to handle lower volumes of similar or even different parts in small

20、er sizes, with means for quick changeover between production runs. Built-in flexibility, the ability to rearrange and interchange machine units, and the provision of idle stations increases the cost of any transfer machi

21、ne, but such feature are economically feasible when product redesigns are common. Many such machines are now being used in nonautomotive app</p><p>　　Special feature now available to reduce the time required

22、 for part changeover include standardized dimensions, modular construction, interchangeable fixtures mounted on master pallets that remain on the machine, interchangeable fixture components, the ability to lock out certa

23、in stations for different parts by means of selector switches, and programmable controllers. Product design is also important, and common transfer and clamping surfaces should be provided on different parts whenever poss

24、ibl</p><p>　　2. Programmable Logic Controllers </p><p>　　A programmable logic controller (PLC) is a solid-state device used to control machine motion or process operation by means of a stored p

25、rogram. The PLC sends output control signals output and receive input signals through input/output (I/O) devices. A PLC controls output in response to stimuli at the inputs according to the logic prescribed by the store

26、d program. The inputs are made up of limit switches, pushbuttons, thumbwheels, switches, pulses, analog signal, ASCII serial data, and binary or</p><p>　　Programmable controllers were developed (circa in 196

27、8) when General Motors Corps, and other automobile manufacturers were experimenting to see if there might be an alternative to scrapping all their hardwired control panel of machine tools and other production equipment d

28、uring a model changeover. This annual tradition was necessary because rewriting of the panels was more expensive than buying new ones.</p><p>　　The automotive companies approached a number of control equipme

29、nt manufacturers and asked them to develop a control system that would have a longer productive life without major rewriting, but would still be understandable to and repairable by the plant personnel. The new product wa

30、s named a “programmable controller”.</p><p>　　The processor part of the PLC contains a central processing unit and memory. The central processing unit (CPU) is the “traffic direction” of the processor, the m

31、emory stores information. Coming into the processor are the electrical signals from the input devices, as conditioned by the input module to voltage levels acceptable to processor logic. The processor scans the state of

32、I/O and updates outputs stored in the memory of the PLC. For example, the processor may be programmed so that if an inp</p><p>　　The output device, such as a solenoid or motor starter, is wired to an output

33、module’s terminal, and it receives its shift signal from the processor, in effect, the processor is performing a long and complicated series of logic decisions. The PLC performs such decisions sequentially and in accordi

34、ng with the stored program. Similarly, analog I/O allows the processor to make decisions based on the magnitude of a signal, rather than just if it is on or off. For example, the processor may be progra</p><p&

35、gt;　　Because a PLC is “software based”, its control logic functions can be changed by reprogramming its memory. Keyboard programming devices facilitate entry of the revised program, which can be design to cause an existi

36、ng machine or process to operate in a different sequence or to different level of, or combinations of stimuli. Hardware modifications are needed only if additional, changed, or relocated input/output device are involved

37、. </p><p>　　3. Automated Assembly</p><p>　　Assembly in the manifacturing process consists of putting together all the component parts and sub-assemblies of a given product, fastening, performi

38、ng inspections and function tests, labeling, separating good assembly from bad, and packaging and or preparing them for final use. Assembly is unique compared to the methods of manufacturing such as machining, grinding,

39、and welding in that most of these processes invovle only a few disciplines and possibly only one. Most of these nonassembly operati</p><p>　　Assembly has traditionally been one of the highest areas of direct

40、 labor costs. In some cases, assembly accounts for 50% or more of manufacturing csosts and typically 20% ～50%. However, closer cooperation between design and manufacturing engineers has resulted in reducing and in a few

41、cases eliminating altogether the need for assembly. When asssembly is required, improved design or products has simplified automated (semiautomatic or automatic) assembly.</p><p>　　Considerations for Automat

42、ed Assembly</p><p>　　Before automated assembly is adopted, several factors should be considerd. These include practicality of the process for automation, simulation for economic considerations and justificat

43、ion, management involvement, and labor relations.</p><p>　　Determining the practicality of automated assembly required careful evaluation of the following:</p><p>　　a)The number of parts in asse

44、mbly.</p><p>　　b)Design of the parts with respect to producibility, assembility, automatic handling, and testability (materials, forms, dimensional tolerances, and weights).</p><p>　　c)Quality o

45、f parts to be assembled. Out-of-tolerance or defective parts can cause production losses and increase costs because of stoppages.</p><p>　　d)Availablity of qualiyied, technically competent personal to be res

46、ponsible for equipment operation.</p><p>　　e) Total production and production-rate requipments.</p><p>　　Product variations and frequency of design changes.</p><p>　　f)Joining metho

47、ds required.</p><p>　　g)Assembly times and costs.</p><p>　　h)Assembly lines or system configuration, using simulation, including material handling.</p><p>　　譯文 <

48、;/p><p>　　1. 自動生產(chǎn)線</p><p>　　使用自動生產(chǎn)線可以利用專用、多功能機(jī)床來實(shí)現(xiàn)最大程度的自動化。自動生產(chǎn)線實(shí)質(zhì)是那些由工件傳送裝置連接起來的按所需順序布置的單個工位的組合，并且通過連鎖控制集成為一體。工件在工位間被自動傳送，每個工位都裝配有用于加工、測量、工件再定位、組裝、清洗或其他操作的臥式、立式及傾斜式設(shè)備。自動生產(chǎn)線的兩大主要類別上旋轉(zhuǎn)式和直列式。</p

49、><p>　　自動生產(chǎn)線的一個顯著優(yōu)點(diǎn)是它們允許同時完成大量的操作。相對來說，對機(jī)加工工件表面或平面的數(shù)量沒有限制，因?yàn)檠b置可介入自動生產(chǎn)線，實(shí)際上在任意位置能使工件翻轉(zhuǎn)、旋轉(zhuǎn)或定向以便完成加工操作。工件重定位也使傾斜主軸箱的數(shù)目減至最小，使操作在最佳時間完成。經(jīng)常可進(jìn)行從原始鑄件或鍛件到成品件的完整加工。</p><p>　　一個或多個成品件在一條帶有每個傳輸系統(tǒng)標(biāo)志的自動生產(chǎn)線上生產(chǎn)，傳輸

50、系統(tǒng)使部件從一個工位運(yùn)動到另一個工位。這類生產(chǎn)線的生產(chǎn)效率通常為50%～85%，由一條生產(chǎn)線生產(chǎn)各式各樣部件時為50%，由一條生產(chǎn)線大批量生產(chǎn)一個部件時達(dá)85%，這取決于工件和如何操作自動生產(chǎn)線（材料處理方法、維護(hù)程序等。</p><p>　　所有類型的機(jī)加工操作，如鉆削、攻絲、鉸削、鏜削和銑削，在自動生產(chǎn)線上被經(jīng)濟(jì)地組合在一起。諸如車削和表面加工的車床式操作也在直列式自動生產(chǎn)線上完成，工件在選擇的機(jī)加工工位上旋

51、轉(zhuǎn)。車削操作在機(jī)床部件完成，多刀架通過安裝在隧道式橋形裝置上的滑軌進(jìn)給。工件定位在中心位置，由在每個車削工位上的卡盤帶動旋轉(zhuǎn)。直列式自動生產(chǎn)線上CNC的車削工位可供使用。CNC裝置允許我們很容易地改變機(jī)器工作周期以適應(yīng)工件設(shè)計的改變而且用于調(diào)整自動刀具。</p><p>　　當(dāng)工件在傳送機(jī)上移動時通過將零件組裝到工件上，經(jīng)?？梢垣@得連續(xù)生產(chǎn)線上最大的生產(chǎn)經(jīng)濟(jì)效益。在傳送加工過程中，能夠?qū)χT如軸襯、密封墊、威爾士襯

52、套和保溫管等零件進(jìn)行組裝、機(jī)加工或測試。完成部件局部裝配后也可進(jìn)行 自動螺帽扭轉(zhuǎn)。</p><p>　　如果能使用合適的機(jī)加工裝置并隨后進(jìn)行良好的操作，在自動生產(chǎn)線上進(jìn)行深鉆孔或鉸削是一項(xiàng)理想的應(yīng)用。球面座和其它表面的仿形鏜削和車削可用仿形控制單點(diǎn)進(jìn)入工件完成，因此取消了昂貴的專用成形刀具。對鉸孔或鏜孔的測量以及自動刀具的調(diào)整是在自動生產(chǎn)線上進(jìn)行的，以保持精確的公差。</p><p>　　

53、有時在自動生產(chǎn)線上進(jìn)行的非常規(guī)加工包括磨削、環(huán)形齒輪的感應(yīng)加熱冷縮配合壓在飛輪上、閥座的感應(yīng)淬火、深度輥壓以施加預(yù)壓載荷和拋光。</p><p>　　自動生產(chǎn)線很早就用于汽車工業(yè)高效率得生產(chǎn)相同部件，手工零件加工量極少。除了減少勞動力需求外，這種生產(chǎn)線能保證低成本生產(chǎn)標(biāo)準(zhǔn)始終如一的、高質(zhì)量零件。它們不再局限于粗加工，現(xiàn)在已經(jīng)常取消了諸如拋光和搪磨這樣的后來工序。</p><p>　　目前，

54、對自動生產(chǎn)線的需求越來越多，用來處理少量的小尺寸的相似的或甚至不同的零件，用于生產(chǎn)經(jīng)營的快速轉(zhuǎn)換。內(nèi)置柔性，即重新布置和互換機(jī)加工設(shè)備的能力，以及提供空轉(zhuǎn)工位增加了每個自動生產(chǎn)線的成本，但是在經(jīng)常重新設(shè)計產(chǎn)品的情況下這些特性是經(jīng)濟(jì)可行的。現(xiàn)在許多這樣的生產(chǎn)線已用在非汽車領(lǐng)域里來滿足少量的生產(chǎn)要求。</p><p>　　現(xiàn)在用于減少零件更換時間的特殊性能包括標(biāo)準(zhǔn)尺寸、模塊結(jié)構(gòu)、安裝在自動生產(chǎn)線主托架上的互換性夾具、

55、可互換性的夾具零件、借助選擇開關(guān)將不同的部件鎖定在具體工位上的能力和可編程控制器。產(chǎn)品設(shè)計也很重要，如可能在不同的零件上應(yīng)提供常見的移動和夾緊用的表面。</p><p>　　2. 可編程序邏輯控制器</p><p>　　可編程邏輯控制器（PLC）是一種固態(tài)電子裝置，它利用已存入的程序來控制機(jī)器的運(yùn)動或工藝的工序。PLC通過輸入/輸出（I/O）裝置信號發(fā)出控制信號和接受輸入信號。PLC依據(jù)以

56、存入程序所規(guī)定的邏輯控制輸出裝置響應(yīng)的激勵。輸入裝置由限位開關(guān)、按鈕、手輪、開關(guān)、脈沖、模擬信號、ASCII系列數(shù)據(jù)和來自于絕對位置解碼的二進(jìn)制或BCD數(shù)據(jù)組成。輸出的是驅(qū)動電磁線圈、電動起動機(jī)、繼電器、指示燈等設(shè)備的電壓或電流電平。其他輸出裝置包括模擬裝置、數(shù)字BCD顯示、ASCII兼容裝置、伺服變速驅(qū)動器、甚至計算機(jī)。</p><p>　　當(dāng)通用汽車公司和其他制造商們正在試驗(yàn)看能否有另一種方法來銷毀型號轉(zhuǎn)變過

57、程中機(jī)床的所有布線控制面板和其他生產(chǎn)設(shè)備時，PLC被研制成了（大約在1968年）。這種年度厲行工作是必要的，因?yàn)榭刂泼姘宓闹匦虏季€比購買新的控制面板要貴得多。</p><p>　　汽車公司與許多控制設(shè)備制造商打交道，請他們開發(fā)一個控制系統(tǒng)，這個系統(tǒng)要有較長的生產(chǎn)壽命而無須主要線路重新布線，并且能被工廠人員所理解和維護(hù)。這個新系統(tǒng)被稱作“可編程控制器”。</p><p>　　PLC的處理器部

58、分由中央處理器和存儲器組成。中央處理器(CPU)是處理器的“交通控制器”，存儲器儲存信息。從輸入裝置來的信號進(jìn)入處理器后，經(jīng)輸入模塊整理成處理器邏輯單元可接受的電壓電平。處理器監(jiān)測I/O的狀態(tài)，然后依據(jù)儲存在PLC存儲器中指令更新輸出。例如，處理器可被編程以便當(dāng)連接限位開關(guān)的輸入位真時（限位開關(guān)閉合），連在輸出上的輸出裝置被連通，例如，這個輸出裝置可以是電磁線圈。處理器通過存儲器記錄下這個指令并與每次檢測相比較以確定限位開關(guān)是否真正閉合

59、。如果閉合，處理器通過接通輸出模塊接通電磁線圈。</p><p>　　諸如電磁線圈或電動機(jī)之類的輸出裝置被連接到輸出模塊的接線柱上，并從處理器接受它的位移信號。實(shí)際上，處理器在完成一系列長而復(fù)雜的邏輯判斷。PLC按順序并根據(jù)存儲的程序來執(zhí)行這樣的判斷。同樣地，模擬 I/O裝置允許處理器依據(jù)信號的大小而不是其接通或關(guān)閉來做判斷。例如，處理器可被編程為根據(jù)鍋爐實(shí)際溫度（模擬輸入）與所需溫度的比較來增加或減少流向鍋爐的

60、蒸汽（模擬輸出）。這通常是用處理器的內(nèi)置PID（比例，積分，微分）能力來實(shí)現(xiàn)的。</p><p>　　因?yàn)镻LC是“基于軟件的”，其控制邏輯功能可通過對存儲器再編程而改變。鍵盤編程裝置使修改的程序的輸入更方便，該程序可以被設(shè)計成使現(xiàn)有機(jī)器或工序以不同順序運(yùn)行，或響應(yīng)不同水平的激勵或激勵組合。只有當(dāng)涉及到附加的更改的或重新定位的輸入/輸出裝置時，才需要修改硬件。 </p>

61、<p>　　3. 自動化組裝 </p><p>　　生產(chǎn)過程中的組裝包括把特定產(chǎn)品的所有元件和組件安裝到一起、對產(chǎn)品進(jìn)行固定、進(jìn)行性能檢測和功能測試、貼標(biāo)簽、區(qū)分良次性、包裝并為最后的使用作好準(zhǔn)備。與切削、磨削、焊接這樣的加工方法相比組裝的獨(dú)特之處在于，這些工序大部分只包括幾個甚至可能只有一個規(guī)則。大多數(shù)這樣的非組裝操作離開設(shè)備就無法進(jìn)行。因此，自動化組裝方法的開發(fā)就成為必然，而非可有可無。另一方面

62、，在一臺機(jī)器上可能要采用多種固定方法進(jìn)行組裝，諸如鉚，焊、上螺釘和使用粘合劑，以及自動選件、探測、測量、功能測試，粘標(biāo)簽和包裝。組裝操作工藝的狀況仍未達(dá)到標(biāo)準(zhǔn)水平，在該領(lǐng)域仍在使用大量的人工操作。</p><p>　　組裝在傳統(tǒng)上已經(jīng)成為直接勞動力成本最高的領(lǐng)域之一。有時，組裝費(fèi)用占生產(chǎn)成本的50%或更多，通常是20%～50%。然而，設(shè)計師與生產(chǎn)技師之間緊密的合作會最終減少甚至在一些情況下排除對組裝的需要。一旦需

63、要組裝的時候，改善產(chǎn)品的設(shè)計或重新設(shè)計能夠簡化自動化（包括全自動和半自動）組裝程序。</p><p><b>　　自動化組裝的考慮 </b></p><p>　　在采用自動化組裝之前，需要考慮幾個因素。其中包括該工序自動化的實(shí)用性、經(jīng)濟(jì)因素與合理性模擬、管理和勞動關(guān)系。決定自動化組裝的實(shí)用性時需要仔細(xì)考慮以下因素：a)組裝中的零件數(shù)量。B)與生產(chǎn)率、組裝能力、自動處理