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1、<p><b>  附 錄</b></p><p><b>  附錄1</b></p><p><b>  英文原文</b></p><p>  Combine tool machine a slippery pedestal the research of the dynamic stat

2、e characteristic</p><p>  【Summary】this text make use of power key to match diagram and appearance space analyticalthe method hurtle and exercise a steady sex problem to carry on analysis and study towards c

3、ombining tool machine slip pedestal of ex-ly, the liquid which builds up a slippery pedestalpresses to drive system a from adjust to carry on the back to press to adjust soon dynamic statemathematics model of system.Pass

4、 a calculator numeral to imitate really, hurtle and exercise notsteady reason and main impact facto</p><p>  One, preface</p><p>  Combine a tool machine work in, the varieties which slip a size

5、 of sport speed and direction andthe load bear all influence degree differently it work function.Especially in the work enter theprocess.Slippery the on the stage load of suddenly disappear causable of ex- hurtle and loa

6、d ofthe period variety cause of the sport gravamen be steady, all is processed the surface quality ofpiece the influence, severity hour will cause the knife break.Request according to tool machinefactory in Dalian, th<

7、;/p><p>  Two, dynamic state mathematics model</p><p>  The liquid which combines tool machine to slip a pedestal presses to drive system a from adjustto carry on the back to press to adjust soon t

8、he work principle diagram of system,such as diagram I, to show.That system is the work circulation which uses to complete "the work enter a stop a back quickly".When slippery pedestal work enter, 34 change to b

9、e placed in diagram to show a right toward the valve, the oil pump of provide hydraulic-pneumatic dint under thefunction which over flows valve look </p><p>  S 1-flow a source, then adjust soon valve export

10、 discharge; </p><p>  Sel-the slippery set glide friction</p><p>  Sel-the slippery set glide friction</p><p>  C5, C6-the etc. effect liquid of tube road permit:</p><p&g

11、t;  R5, R7-take care of an etc. of road effect liquid Zu;</p><p>  V3, the V4-oil urn has no pole chamber and has a pole chamber the contents to accumulate;</p><p>  P3, the pressure which have

12、no pole chamber and have a pole chamber of the P4-oil urn</p><p>  F-the slippery set bear a load,</p><p>  V-slip a pedestal sport speed.The this literary grace hard working rate key matches di

13、agram and appearance space to fold a method establishment sport mathematics model of the system for cent.</p><p>  Power key's matching diagram is an effect to flow diagram, it is the energy which presse

14、s system to deliver a way, take actual structure as foundation, the function which uses concentration parameter the of sub- system relates to an abstract earth's surface to show for the Zu a dollar Rand permits sex d

15、ollar C and sensitive faculty dollar I of three kinds of function dollar.Adopt thiskind of method sets up a mold physical concept clear, combine the appearance space analysis method can compare to</p><p>  A

16、ccording to from adjust to carry on the back to press to adjust soon the main characteristic ofeach component of system and set up mold rule[1], get figure 3 show of the power key of system match diagram.Each half arrowh

17、ead on the key in diagram means that the power fly to, 2 which constitute power change the quantity be a dint to change to measure(hydraulic-pneumatic P or function dint F) and flow to change to measure(discharge q or sp

18、eed v).O crunode means in the system to belong to merge a c</p><p>  Four, slip the exercise of pedestal steady </p><p>  While regarding as a load period of used for the slippery on the stage v

19、ariety(if the Xian pares to process a circumstance), the sport speed which slips a pedestal wants to produce certain。motion.In order to process the request of quality at assurance, have to possibly let up its speed motio

20、n scope.Set out from the convenience discussed a problem, suppose a load by the sine wave regulation variety, get thus of numeral imitate a true result such as figure 5 show.Be showed from this that system an</p>

21、<p>  Five, improve measure</p><p>  Study result enunciation, with from adjust to carry on the back to press to adjust soon system for drive the slippery set of system, its dynamic state characteristic

22、 surpasses to traditionally adjustsoon system.Want to reduce the ex- blunt quantity of slippery pedestal, must be load the disappeared moment quickly raises an oil urn have a pole chamber of carry on the back pressure;Wa

23、nt to raise the exercise of slippery pedestal steady to need to increase system of rigid, the main measure lies in </p><p>  Six, conclusion</p><p>  Imitate a true research through theories ana

24、lysis and calculator, from adjust to carry on the back to press to adjust soon system Be combine a drive of the tool machine slippery pedestal system to have much of expansion use value.The main factor which influences a

25、 slippery pedestal dynamic state characteristic is oil urn internal structure with from adjust to carry on the back topress valve of size.If as to it's carry on a reasonable design, the dynamic state characteristic c

26、anmake to slip a ped</p><p>  In 1946 the first electronic accounting machine was born in the world, thisindicated the humanity created has been possible to strengthen and partially toreplace the mental labo

27、r the tool. It with the humanity these which in the agriculture, the industry society created only is strengthens the physical labor the tool to compare, got up the quantitive leap, entered the information society for t

28、he humanity to lay the foundation.</p><p>  After 6 years, in 1952, computer technology applied to the engine bed , the first numerical control engine bed were born in US. From this time on, thetraditional e

29、nginebed hashad the archery target change. Since nearly half century, the numerical control system has experienced two stages and six generation of development.</p><p>  The early computer operating speed is

30、 low, was not big to then science computation and the data processing influence, but could not adapt the engine bed real-time control request. The people can not but use numeral logic circuit "to build" to beco

31、me an engine bed special purpose computer to take the numerical control system, is called the hardware connection numerical control (HARD-WIREDNC), Jian Chengwei numerical control (NC). Along with the primary de

32、vicedevelopment, this stage has h</p><p>  In 1970, the general minicomputer already appeared and the mass production. Thereupon transplants it takes the numerical control system the core part, from this tim

33、e on entered the computer numerical control (CNC)the stage ("which shouldhave computer in front of the general" two characters to abbreviate). In 1971, American INTEL Corporation in the world first time the com

34、puter two most cores part -- logic units and the controller, used the large scale integrated circuit technology integration o</p><p>  The microprocessor is applied to 1974 in the numerical control system.

35、This is because minicomputer function too strong, controlled an engine bed ability to have wealthily (therefore once uses in controlling the multi- Taiwan engine bed at that time, called it group control), was inferior t

36、o used the microprocessor economy to be reasonable. Moreover then small machine reliability was not ideal. The early microprocessor speed and the function although insufficiently are alsohigh, but may solve t</p>

37、<p>  In 1990, PC machine (personal computer, domestic custom had called microcomputer) the performance has developed to the very high stage, may satisfiedly take the numerical control system core part the reques

38、t. The numerical control system henceforth entered based on the PC stage.</p><p>  In brief, the computer numerical control stage has also experienced three generations. Namely 1970fourth generation of

39、-- minicomputer; 1974five dynasties-- microprocessor and 1990sixth generation -- (overseaswascalledPC-BASED) based on PC.</p><p>  onto this path. Uses PC machine to take at least its front end machine, proc

40、esses the man-machine contact surface, the programming, the association.Question and so on net correspondence, undertakes the numerical control duty by the original system. PC machine has the friendly man-machine contact

41、 surface, will popularize to all numerical controls system. The long-distancecommunication, the long-distance diagnosis and the service will be more common.</p><p>  Along with the artificial intelligence in

42、 the computer domain unceasing seepage and the development, the numerical control system intellectualized degree unceasingly will enhance.</p><p>  applies the adaptive control technology</p><p>

43、;  The numerical controlsystem can examine in theprocess some important information, and the automatic control system related parameter, achieves the improvement system running status the goal.</p><p>  intr

44、oduces the expert system instruction processing</p><p>  The skilled worker and expert's experience, the processing general rule and the special rule store in the system, take the craft parameter databas

45、e as the strut, the establishment has the artificial intelligence the expert system.</p><p>  introduces the breakdown to diagnose the expert system</p><p>  intellectualized numeral servo drive

46、</p><p>  May through the automatic diagnosis load, but the automatic control parameter, causes the actuation system to obtain the best movement. Second, engine bed numerical control transformation necessity

47、</p><p>  From on microscopic looked below that, the numerical control engine bed has the prominent superiority compared to the traditional engine bed, moreover these superiority come from the computer might

48、 which the numerical control system contains. may process the traditional engine bed cannot process the curve, the curvedsurface and so on the complex components.</p><p>  Because the computer has the excell

49、ent operation ability, may the instant accurately calculate each coordinate axis instant to be supposed the movement physiological load of exercise, therefore may turn round the synthesis complex curve or the curved sur

50、face.</p><p>  may realize the processing automation, moreover is the flexible automation, thus the efficiency may enhance 3 ~ 7 times compared to the traditional engine bed.</p><p>  Because t

51、he computer has the memory and the memory property, may the procedure which inputs remember and save, then the order which stipulated according to the procedure automatic carries out, thus realization automation. The num

52、erical control engine bed so long as replaces a procedure, may realize another work piece processing automation, thus causes the single unit and the small batch of production can automate, therefore is called has reali

53、zed "flexible automation".</p><p>  From on macroscopic looked that, the industry developed country armed forces, the airplane weapon industry, in the end of the 70's, at the beginning of the 8

54、0's started the large-scale application numerical control engine bed. Its essence is, uses the information technology to the traditional industry (includingthe armed forces, airplane weapon industry) carries on the t

55、echnological transformations. Except that uses outside the numerical control engine bed, FMC, FMS in themanufacture process, bu</p><p>  In US, Japan and Germany and so on the developed country, their engine

56、 bed transforms took the new economical growth profession, thrives abundantly, is occupying the golden age. As a result of the engine bed as well as the technicalunceasing progress, the engine bed transformation is "

57、;the eternal" topic. Our unceasing progress, the engine bed transformation is "the eternal" topic. Our unceasing progress, the engine bed transformation is "the eternal" topic. Our Germany,have t

58、he broad market with</p><p>  The engine bed and the production line numerical control transformation main</p><p>  content has following several points:</p><p>  First is extensive

59、ly recovers the function, to the engine bed, the production line has the breakdown partially to carry on the diagnosis and the restoration;</p><p>  Second is NC, the addend reveals the installment on the or

60、dinary engine bed, or adds the numerical control system, transforms the NC engine bed, the CNC engine bed;</p><p>  Third is renovates, for increases the precision, the efficiency and theautomaticity, to the

61、 machinery, the electricity partially carries on renovates, reassembles the processing to themachine part, extensively recovers the precision; reassembles the processing to themachine part, extensively recovers the preci

62、sion; by newest CNC;</p><p>  Fourth is the technology renews or the technical innovation, for enhances the performance or the scale, or in order to use the new craft, the new technology, carries on the big

63、scale in the original foundation the technology to renew or the technical innovation, the great scope raises the level and the scale renewal transformation.The new electrical system transforms after, how carries on the d

64、ebugging as well as the determination reasonable approval standard, also is the technology preparatory </p><p><b>  中文翻譯</b></p><p>  組合機(jī)床滑臺(tái)動(dòng)態(tài)特性的研究</p><p>  【摘要】本 利用功率鍵合

65、圖和狀態(tài)空間分析法對(duì)組合機(jī)床滑臺(tái)的前沖和運(yùn)動(dòng)平穩(wěn)性問(wèn)題進(jìn)行分析與研究,建立了滑臺(tái)的液壓驅(qū)動(dòng)系統(tǒng)一自調(diào)背壓調(diào)速系統(tǒng)的動(dòng)態(tài)數(shù)學(xué)模型。通過(guò)計(jì)算機(jī)數(shù)字仿真,分析了滑臺(tái)產(chǎn)生前沖和運(yùn)動(dòng)不平穩(wěn)的原 及主要影響 素。從中得出,如果合理地設(shè)計(jì)液壓缸和自調(diào)背壓調(diào)壓閥的結(jié)構(gòu)尺寸,可以使滑臺(tái)的動(dòng)態(tài)特性得到顯著改善。</p><p><b>  1引言</b></p><p>  組合機(jī)床工作

66、中,滑臺(tái)運(yùn)動(dòng)速度的大小和方向以及所承受負(fù)載的變化都將程度不同地影響其工作性能。特別是在工進(jìn)過(guò)程中?;_(tái)上負(fù)載的突然消失引起的前沖以及負(fù)載的周期變化引起的運(yùn)動(dòng)不平穩(wěn),都將影響被加工件的表面質(zhì)量,嚴(yán)重時(shí)會(huì)致使刀具折斷。根據(jù)大連機(jī)床廠要求,作者采用功率鍵合圖和狀態(tài)空間分析法建立組合機(jī)床滑臺(tái)的新型液壓驅(qū)動(dòng)系統(tǒng)一自調(diào)背壓調(diào)速系統(tǒng)的動(dòng)態(tài)數(shù)學(xué)模型。通過(guò)計(jì)算機(jī)數(shù)字仿真和研究。分析滑臺(tái)產(chǎn)生前沖和運(yùn)動(dòng)不平穩(wěn)的原 以及主要的影響,以便改善滑臺(tái)的動(dòng)態(tài)特性。&l

67、t;/p><p><b>  2動(dòng)態(tài)數(shù)學(xué)模型</b></p><p>  組合機(jī)床滑臺(tái)的液壓驅(qū)動(dòng)系統(tǒng)一自調(diào)背壓調(diào)速系統(tǒng)的工作原理圖如圖I所示。該系統(tǒng)是用來(lái)完成"工進(jìn)一停止一快退”的工作循環(huán)。當(dāng)滑臺(tái)工進(jìn)時(shí),三位四通換向閥處于圖示右位,油泵的供油壓力在濫流閥的作用下近似地保持恒定,該油液流經(jīng)換向閥和調(diào)速閥后進(jìn)入油缸的無(wú)桿腔,推動(dòng)滑臺(tái)左移;同時(shí),油缸有桿腔排出的壓力油

68、經(jīng)自調(diào)背壓閥和換向閥流回油箱。在此過(guò)程中,兩個(gè)單向閥和溢流閥始終沒(méi)有改變?cè)械墓ぷ鳡顟B(tài)。對(duì)象該系統(tǒng)這樣的復(fù)雜非線(xiàn)性系統(tǒng),為了便于研究其動(dòng)態(tài)特性,建立一個(gè)僅著重考慮主要影響因素的合理簡(jiǎn)單的動(dòng)態(tài)數(shù)學(xué)模型是尤其重要的[1][2]。從理論分析和試驗(yàn)研究中得知:該系統(tǒng)的過(guò)程時(shí)間是遠(yuǎn)大于調(diào)速閥的過(guò)程時(shí)間的,油缸無(wú)桿腔有效承壓面積很大,調(diào)速閥出口流量的瞬時(shí)超調(diào)反映為滑臺(tái)運(yùn)動(dòng)速度的變化是很小的[2]。為了拓寬和深入研究系統(tǒng)的動(dòng)態(tài)特性,使研究工作能在微型

69、計(jì)算機(jī)上有效地進(jìn)行,本 對(duì)原模型[2]做進(jìn)一步簡(jiǎn)化,假定調(diào)速閥在系統(tǒng)的整個(gè)過(guò)渡過(guò)程中輸出恒定的流量,視其為流源。這樣,系統(tǒng)的動(dòng)態(tài)模型的結(jié)構(gòu)簡(jiǎn)圖如圖2 所示,它是由油缸、滑臺(tái),自凋背壓閥和聯(lián)接管路等組成。本論文中所使用的符號(hào):</p><p>  s1-流源,即調(diào)速閥出口流量;</p><p>  Sel—滑臺(tái)滑動(dòng)摩擦力</p><p>  R 一滑臺(tái)等效粘性摩擦系數(shù)

70、</p><p>  I1—滑臺(tái)與油缸的質(zhì)量12—自調(diào)背壓閥閥心質(zhì)量</p><p>  C1、c2—油缸無(wú)桿腔及有桿腔的液容</p><p>  C2—自調(diào)背壓閥彈簧柔度</p><p>  R1, R2 自調(diào)背壓閥阻尼孔液阻,</p><p>  R9—自調(diào)背壓閥閥口液阻</p><p> 

71、 Se2—自調(diào)背壓閥彈簧的初始預(yù)緊力;</p><p>  I4, I5—管路的等效液感</p><p>  C5、C6—管路的等效液容:</p><p>  R5, R7-管路的等效液阻;</p><p>  V3, V4—油缸無(wú)桿腔及有桿腔內(nèi)容積;</p><p>  P3, P4—油缸無(wú)桿腔及有桿腔的壓力<

72、/p><p><b>  F—滑臺(tái)承受負(fù)載,</b></p><p>  滑臺(tái)前沖現(xiàn)象是作用在滑臺(tái)上的負(fù)載突然消失(如鉆透工作情況)引起的。在此過(guò)程中,滑臺(tái)的負(fù)載F、運(yùn)動(dòng)速度V、油缸兩腔壓力P3 和P4 的變化可從圖4 仿真結(jié)果看出。當(dāng)滑臺(tái)在負(fù)載的作用下勻速運(yùn)動(dòng)時(shí),油缸無(wú)桿腔油液壓力較高.油液中聚集了大量的能量。當(dāng)負(fù)載突然消失時(shí),該腔油壓隨之迅速降低,油液從高壓態(tài)轉(zhuǎn)入低壓

73、態(tài)的過(guò)程中向系統(tǒng)釋放很多能量,致使滑臺(tái)高速向前沖擊。然而,滑臺(tái)的前沖使油缸有桿腔油液受壓引起背壓升高,從而消耗掉系統(tǒng)中的一部分能量,對(duì)滑臺(tái)的前沖起一定的抑制作用。應(yīng)當(dāng)看到,在所研究的系統(tǒng)中,自調(diào)背壓閥的入口壓力要受到油缸兩腔油壓的綜合作用。在負(fù)載消失的瞬間,自調(diào)背壓閥的壓力迅速上升,并穩(wěn)定在高于初始背壓的數(shù)值上。從圖中可見(jiàn),自調(diào)背壓調(diào)速系統(tǒng)在負(fù)載消失瞬間油缸背壓力升高的幅度大于傳統(tǒng)的調(diào)速系統(tǒng),所以,其油缸有桿腔中油液吸收的能量 多;結(jié)果

74、,滑臺(tái)的前沖量比傳統(tǒng)調(diào)速系統(tǒng)要小近20%??梢?jiàn)采用自調(diào)背莊調(diào)速系統(tǒng)作為驅(qū)動(dòng)系統(tǒng)的滑臺(tái)在抑制前沖方面具有良好的特性,其中自調(diào)背壓閥起了很大作用。</p><p>  四.滑臺(tái)的運(yùn)動(dòng)平穩(wěn)性</p><p>  當(dāng)作用于滑臺(tái)上的負(fù)載周期變化時(shí)(如銑削加工情況),滑臺(tái)的運(yùn)動(dòng)速度要產(chǎn)生一定的波動(dòng)。為于保 加工質(zhì)量的要求,必須盡可能地減小其速度波動(dòng)范圍。從討論問(wèn)題的方便出發(fā),假設(shè)負(fù)載按正弦波規(guī)律變化,

75、從而得到的數(shù)字仿真結(jié)果如圖5所示。由此可見(jiàn)該系統(tǒng)與傳統(tǒng)的調(diào)速系統(tǒng)有著相同的變化規(guī)律和非常接近的數(shù)值。原 是負(fù)載的變化幅度不大,油缸兩腔壓力也 沒(méi)有較大變化,最終導(dǎo)致自調(diào)背壓閥的作用不夠明顯。</p><p><b>  五、改善措施</b></p><p>  研究結(jié)果表明,以自調(diào)背壓調(diào)速系統(tǒng)為驅(qū)動(dòng)系統(tǒng)的滑臺(tái),其動(dòng)態(tài)特性?xún)?yōu)于傳統(tǒng)的調(diào)速系統(tǒng)。要減少滑臺(tái)的前沖量, 必需在

76、負(fù)載消失的瞬間迅速提高油缸有桿腔的背壓力;要提高滑臺(tái)的運(yùn)動(dòng)平穩(wěn)性 需增加系統(tǒng)的剛性,主要措施在于減小油液的體積。從系統(tǒng)的結(jié)構(gòu)得知,油缸有桿腔與排油管間有一很大的容積,如圖6a 所示。它的存在方面延遲和衰減了自調(diào)背壓閥的作用,另一方面也降低了系統(tǒng)的剛性,它限制了前沖特性和運(yùn)動(dòng)平穩(wěn)性的進(jìn)一步改善。因此,改善滑臺(tái)動(dòng)態(tài)特性可從兩個(gè)途徑進(jìn)行:即改變油缸容積和改變自調(diào)背壓閥結(jié)構(gòu)尺寸。通過(guò)一系統(tǒng)結(jié)構(gòu)參數(shù)的仿真計(jì)算以及結(jié)果的比較可以得出:當(dāng)把油缸有桿腔

77、與排油管間容積V4 同無(wú)桿腔與進(jìn)油管間容積V3 之比由原來(lái)的5.5 改為1 時(shí),如圖6b 所示,同時(shí),把自調(diào)背壓閥閥芯底 直徑由原來(lái)的10mm 增加為 13mm,阻尼三角槽邊長(zhǎng)從原來(lái)的lmm 減小到0.7mm 時(shí),可使滑臺(tái)的前沖量減小30%,過(guò)渡過(guò)程時(shí)間明顯縮短,滑臺(tái)的運(yùn)動(dòng)平穩(wěn)性得到很大改善。</p><p>  通過(guò)理論分析和計(jì)算機(jī)仿真研究,自調(diào)背壓調(diào)速系統(tǒng)作為組合機(jī)床滑臺(tái)的驅(qū)動(dòng)系統(tǒng)是很有推廣使用價(jià)值的。影響滑

78、臺(tái)動(dòng)態(tài)特性的主要 素是油缸內(nèi)部結(jié)構(gòu)和自調(diào)背壓閥的尺寸。若對(duì)其進(jìn)行合理設(shè)計(jì),可使滑臺(tái)的動(dòng)態(tài)特性得到顯著地改善。同時(shí),也說(shuō)明了采用功率鍵合圖和狀態(tài)空間分析法研究復(fù)雜非線(xiàn)性是方便有效的。</p><p>  1946年誕生了世界上第一臺(tái)電子計(jì) 機(jī),這表明人類(lèi)創(chuàng)造了可增強(qiáng)和部分代替腦力勞動(dòng)的工具。它與人類(lèi)在農(nóng)業(yè)、工業(yè)社會(huì)中創(chuàng)造的那些只是增強(qiáng)體力勞動(dòng)的工具相比,起了質(zhì)的飛躍,為人類(lèi)進(jìn)入信息社會(huì)奠定了基礎(chǔ)。</p>

79、;<p>  6年后即在1952年,計(jì)算機(jī)技術(shù)應(yīng)用到了機(jī)床上,在美國(guó)誕生了第一臺(tái)數(shù)控機(jī)床。從此,傳統(tǒng)機(jī)床產(chǎn)生了質(zhì)的變化。近半個(gè)世紀(jì)以來(lái),數(shù)控系統(tǒng)經(jīng)歷了兩個(gè)階段和六代的發(fā)展。</p><p>  早期計(jì)算機(jī)的運(yùn)算速度低,對(duì)當(dāng)時(shí)的科學(xué)計(jì)算和數(shù)據(jù)處理影響還不大,但不能適應(yīng)機(jī)床實(shí)時(shí)控制的要求。人們不得不采用數(shù)字邏輯電路"搭"成一臺(tái)機(jī)床專(zhuān)用計(jì) 機(jī)作為數(shù)控系統(tǒng),被稱(chēng)為硬件連接數(shù)控(HARD-

80、WIRED NC),簡(jiǎn)稱(chēng)為數(shù)控(NC)。隨著元器件的發(fā)展,這個(gè)階段歷經(jīng)了三代,即1952年的第一代--電子管;1959年的第二代--晶體管;1965年的第三代--小規(guī)模集成電路。</p><p>  到 1970 年,通用小型計(jì) 機(jī)業(yè)已出現(xiàn)并成批生產(chǎn)。于是將它移植過(guò)來(lái)作為數(shù)控系統(tǒng)的核心部件,從此進(jìn)入了計(jì) 機(jī)數(shù)控 (CNC)階段 (把計(jì) 機(jī)前面應(yīng)有的"通用"兩個(gè)字省略了)。到1971年,美國(guó)IN

81、TEL 公司在世界上第一次將計(jì) 機(jī)的兩個(gè)最核心的部件--運(yùn)器和控制器,采用大規(guī)模集成電路技術(shù)集成在一塊芯片上,稱(chēng)之為微處理器(MICROPROCESSOR),又可稱(chēng)為中央處理單元 (簡(jiǎn)稱(chēng)CPU)。到 1974 年微處理器被應(yīng)用于數(shù)控系統(tǒng)。這是因?yàn)樾⌒陀?jì) 機(jī)功能太強(qiáng),控制一臺(tái)機(jī)床能力有富裕(故當(dāng)時(shí)曾用于控制多臺(tái)機(jī)床,稱(chēng)之為群控),不如采用微處理器經(jīng)濟(jì)合理。而且當(dāng)時(shí)的小型機(jī)可靠性也不理想。早期的微處理器速度和功能雖還不夠高,但可以通過(guò)多處理

82、器結(jié)構(gòu)來(lái)解決。由于微處理器是通用計(jì) 機(jī)的核心部件,故仍稱(chēng)為計(jì) 機(jī)數(shù)控。</p><p>  到了1990年,PC 機(jī)的性能已發(fā)展到很高的階段,可以滿(mǎn) 作為數(shù)控系統(tǒng)核心部件的要求。數(shù)控系統(tǒng)從此進(jìn)入了基于PC 的階段。</p><p>  總之,計(jì)算機(jī)數(shù)控階段也經(jīng)歷了三代。即1970年的第四代--小型計(jì)算機(jī);1974年的第五代--微處理器和1990年的第六代--基于PC(也就是為PC-BASE

83、D)。</p><p>  基于PC 所具有的開(kāi)放性、低成本、高可靠性、軟硬件資源豐富等特點(diǎn),更多的數(shù)控系統(tǒng)生產(chǎn)廠家會(huì)走上這條道路。至少采用PC 機(jī)作為它的前端機(jī),來(lái)處理人機(jī)界面、編程、聯(lián)網(wǎng)通信等問(wèn)題,由原有的系統(tǒng)承擔(dān)數(shù)控的任務(wù)。PC 機(jī)所具有的友好的人機(jī)界面,將普及到所有的數(shù)控系統(tǒng)。遠(yuǎn)程通訊,遠(yuǎn)程診斷和維修將更加普遍。</p><p>  隨著人工智能在計(jì) 機(jī)領(lǐng)域的不斷滲透和發(fā)展,數(shù)控系

84、統(tǒng)的智能化程度將不斷提高。</p><p>  1應(yīng)用自適應(yīng)控制技術(shù)</p><p>  數(shù)控系統(tǒng)能檢測(cè)過(guò)程中一些重要信息,并自動(dòng)調(diào)整系統(tǒng)的有關(guān)參數(shù),達(dá)到改進(jìn)系統(tǒng)2運(yùn)行狀態(tài)的目的。</p><p>  3引入專(zhuān)家系統(tǒng)指導(dǎo)加工</p><p>  將熟練工人和專(zhuān)家的經(jīng)驗(yàn),加工的一般規(guī)律和特殊規(guī)律存入系統(tǒng)中,以工藝參數(shù)數(shù)據(jù)庫(kù)為支撐,建立具有人工智

85、能的專(zhuān)家系統(tǒng)。</p><p>  4引入故障診斷專(zhuān)家系統(tǒng)</p><p>  5智能化數(shù)字伺服驅(qū)動(dòng)裝置</p><p>  可以通過(guò)自動(dòng)識(shí)別負(fù)載,而自動(dòng)調(diào)整參數(shù),使驅(qū)動(dòng)系統(tǒng)獲得最 的運(yùn)行。</p><p>  從微觀上看,數(shù)控機(jī)床比傳統(tǒng)機(jī)床有以下突出的優(yōu)越性,而且這些優(yōu)越性均來(lái)自數(shù)控系統(tǒng)所包含的計(jì)算機(jī)的威力??梢约庸こ鰝鹘y(tǒng)機(jī)床加工不出來(lái)的曲

86、線(xiàn)、曲面等復(fù)雜的零件。由于計(jì)算機(jī)有高超的運(yùn)算能力,可以瞬時(shí)準(zhǔn)確地計(jì)算出每個(gè)坐標(biāo)軸瞬時(shí)應(yīng)該運(yùn)動(dòng)的運(yùn)動(dòng)量,因此可以復(fù)合成復(fù)雜的曲線(xiàn)或曲面??梢詫?shí)現(xiàn)加工的自動(dòng)化,而且是柔性自動(dòng)化,從而效率可比傳統(tǒng)機(jī)床提高3~7 倍。</p><p>  由于計(jì) 機(jī)有記憶和存儲(chǔ)能力,可以將輸入的程序記住和存儲(chǔ)下來(lái),然后按程序規(guī)定的順序自動(dòng)去執(zhí)行,從而實(shí)現(xiàn)自動(dòng)化。數(shù)控機(jī)床只要更換一個(gè)程序,就可實(shí)現(xiàn)另一工件加工的自動(dòng)化,從而使單件和小批生產(chǎn)

87、得以自動(dòng)化,故被稱(chēng)為實(shí)現(xiàn)了"柔性自動(dòng)化"。</p><p>  加工零件的精度高,尺寸分散度小,使裝配容易,不再需要"修配"。可實(shí)現(xiàn)多工序的集中,減少零件 在機(jī)床間的頻繁搬運(yùn)。擁有自動(dòng)報(bào)警、自動(dòng)監(jiān)控、自動(dòng)補(bǔ)償?shù)榷喾N自律功能,因而可實(shí)現(xiàn)長(zhǎng)時(shí)間無(wú) 看管加工。如:降低了工人的勞動(dòng)強(qiáng)度,節(jié)省了勞動(dòng)力 (一個(gè)人可以看管多臺(tái)機(jī)床),減少了工裝,縮短了新產(chǎn)品試制周期和生產(chǎn)周期,可對(duì)市場(chǎng)需

88、求作出快速反應(yīng)等等。</p><p>  以上這些優(yōu)越性是前人想象不到的,是一個(gè)極為重大的突破。此外,機(jī)床數(shù)控化還是推行FMC (柔性制造單元)、FMS (柔性制造系統(tǒng))以及CIMS (計(jì) 機(jī)集成制造系統(tǒng))等企業(yè)信息化改造的基礎(chǔ)。數(shù)控技術(shù)已經(jīng)成為制造業(yè)自動(dòng)化的核心技術(shù)和基礎(chǔ)技術(shù)。</p><p>  從宏觀上看,工業(yè)發(fā)達(dá)國(guó)家的軍、民機(jī)械工業(yè),在70 年代末、80 年代初已開(kāi)始大規(guī)模應(yīng)用數(shù)控

89、機(jī)床。其本質(zhì)是,采用信息技術(shù)對(duì)傳統(tǒng)產(chǎn)業(yè) (包括軍、民機(jī)械工業(yè))進(jìn)行技術(shù)改造。除在制造過(guò)程中采用數(shù)控機(jī)床、FMC、FMS 外,還包括在產(chǎn)品開(kāi)發(fā)中推行CAD、CAE、CAM、虛擬制造以及在生產(chǎn)管理中推行MIS (管理信息系統(tǒng))、CIMS 等等。以及在其生產(chǎn)的產(chǎn)品中增加信息技術(shù),包括人工智能等的含量。由于采用信息技術(shù)對(duì)國(guó)外軍、民機(jī)械工業(yè)進(jìn)行深入改造(稱(chēng)之為信息化),最終使得他們的產(chǎn)品在國(guó)際軍品和民品的市場(chǎng)上競(jìng)爭(zhēng)力大為增強(qiáng)。</p>

90、<p>  在美國(guó)、日本和德國(guó)等國(guó)家,機(jī)床改造作為新的經(jīng)濟(jì)增長(zhǎng)行業(yè),生意盎然,正處在黃金時(shí)代。由于機(jī)床以及技術(shù)的不斷進(jìn)步,機(jī)床改造是個(gè)"永恒"的課題。在美國(guó)、日本、德國(guó),用數(shù)控技術(shù)改造機(jī)床和生產(chǎn)線(xiàn)具有廣闊的市場(chǎng),已形成了機(jī)床和生產(chǎn)線(xiàn)數(shù)控改造的新的行業(yè)。在美國(guó),機(jī)床改造業(yè)稱(chēng)為機(jī)床再生 (Remanufacturing)業(yè)。從事再生業(yè)的著名公司有:Bertsche 工程公司、ayton 機(jī)床公司、Devli

91、eg-Bullavd (得寶)服務(wù)集團(tuán)、US設(shè)備公司等。。在日本,機(jī)床改造業(yè)稱(chēng)為機(jī)床改裝 (Retrofitting)業(yè)。從事改裝業(yè)的著名公司有:大隈工程集團(tuán)、崗三機(jī)械公司、千代田工機(jī)公司、野崎工程公司、濱田工程公司、山本工程公司等。</p><p>  機(jī)床與生產(chǎn)線(xiàn)的數(shù)控化改造主要內(nèi)容有以下幾點(diǎn):</p><p>  其一是恢復(fù)原功能,對(duì)機(jī)床、生產(chǎn)線(xiàn)存在的故障部分進(jìn)行診斷并恢復(fù);<

92、/p><p>  其二是NC 化,在普通機(jī)床上加數(shù)顯裝置,或加數(shù)控系統(tǒng),改造成NC 機(jī)床、CNC機(jī)床;</p><p>  其三是翻新,為提高精度、效率和自動(dòng)化程度,對(duì)機(jī)械、電氣部分進(jìn)行翻新,對(duì)機(jī)械部分重新裝配加工,恢復(fù)原精度;對(duì)其不滿(mǎn)足生產(chǎn)要求的CNC 系統(tǒng)以最新CNC 進(jìn)行更新;</p><p>  其四是技術(shù)更新或技術(shù)創(chuàng)新,為提高性能或檔次,或?yàn)榱耸褂眯鹿に?、新?/p>

93、術(shù),在原有基礎(chǔ)上進(jìn)行較大規(guī)模的技術(shù)更新或技術(shù)創(chuàng)新,較大幅度地提高水平和檔次的更新改造。</p><p>  同購(gòu)置新機(jī)床相比,一般可以節(jié)省60%~80%的費(fèi)用,改造費(fèi)用低。特別是大型、特殊機(jī)床尤其明顯。一般大型機(jī)床改造,只花新機(jī)床購(gòu)置費(fèi)用的 1/3,交貨期短。但有些特殊情況,如高速主軸、托盤(pán)自動(dòng)交換裝置的制作與安裝過(guò)于費(fèi)工、費(fèi)錢(qián),往往改造成本提高2~3倍,與購(gòu)置新機(jī)床相比,只能節(jié)省投資50%左右。所利用的床身、立

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