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1、<p><b>  機(jī)床數(shù)控改造淺談</b></p><p>  一、數(shù)控系統(tǒng)發(fā)展簡(jiǎn)史及趨勢(shì)</p><p>  1946年誕生了世界上第一臺(tái)電子計(jì)算機(jī),這表明人類創(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,為人類進(jìn)入信息社會(huì)奠定了基礎(chǔ)。 </p><p>  6

2、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,數(shù)控系統(tǒng)經(jīng)歷了兩個(gè)階段和六代的發(fā)展。 </p><p>  1.1、數(shù)控(NC)階段(1952~1970年) </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&qu

3、ot;成一臺(tái)機(jī)床專用計(jì)算機(jī)作為數(shù)控系統(tǒng),被稱為硬件連接數(shù)控(HARD-WIRED NC),簡(jiǎn)稱為數(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>  1.2、計(jì)算機(jī)數(shù)控(CNC)階段(1970年~現(xiàn)在) </p><p>  到1970年,通用小型計(jì)算機(jī)業(yè)已出現(xiàn)并成批生

4、產(chǎn)。于是將它移植過來作為數(shù)控系統(tǒng)的核心部件,從此進(jìn)入了計(jì)算機(jī)數(shù)控(CNC)階段(把計(jì)算機(jī)前面應(yīng)有的"通用"兩個(gè)字省略了)。到1971年,美國(guó)INTEL公司在世界上第一次將計(jì)算機(jī)的兩個(gè)最核心的部件--運(yùn)算器和控制器,采用大規(guī)模集成電路技術(shù)集成在一塊芯片上,稱之為微處理器(MICROPROCESSOR),又可稱為中央處理單元(簡(jiǎn)稱CPU)。 </p><p>  到1974年微處理器被應(yīng)用于數(shù)控系

5、統(tǒng)。這是因?yàn)樾⌒陀?jì)算機(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,但可以通過多處理器結(jié)構(gòu)來解決。由于微處理器是通用計(jì)算機(jī)的核心部件,故仍稱為計(jì)算機(jī)數(shù)控。 </p><p>  到了1990年,PC機(jī)(個(gè)人計(jì)算機(jī),國(guó)內(nèi)習(xí)慣稱微機(jī))的性能已發(fā)展到很高的階段,可以滿足作為數(shù)控系統(tǒng)核心部件的要求。數(shù)

6、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(國(guó)外稱為PC-BASED)。 </p><p>  還要指出的是,雖然國(guó)外早已改稱為計(jì)算機(jī)數(shù)控(即CNC)了,而我國(guó)仍習(xí)慣稱數(shù)控(NC)。所以我們?nèi)粘Vv的"數(shù)控",實(shí)質(zhì)上已是指&qu

7、ot;計(jì)算機(jī)數(shù)控"了。 </p><p>  1.3、數(shù)控未來發(fā)展的趨勢(shì) </p><p>  1.3.1 繼續(xù)向開放式、基于PC的第六代方向發(fā)展 </p><p>  C所具有的開放性、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),來處理人機(jī)界面、編程、聯(lián)網(wǎng)通信等問題,由原有的系統(tǒng)承擔(dān)數(shù)控的任

8、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>  1.3.2 向高速化和高精度化發(fā)展 </p><p>  應(yīng)機(jī)床向高速和高精度方向發(fā)展的需要。 </p><p>  1.3.3 向智能化方向發(fā)展 </p><p>  隨著人工智能在計(jì)算機(jī)領(lǐng)域的不斷滲透和發(fā)展,數(shù)控系統(tǒng)的智能化

9、程度將不斷提高。 </p><p> ?。?)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)運(yùn)行狀態(tài)的目的。 </p><p> ?。?)引入專家系統(tǒng)指導(dǎo)加工 </p><p>  將熟練工人和專家的經(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)庫為支撐,建立具有人

10、工智能的專家系統(tǒng)。 </p><p> ?。?)引入故障診斷專家系統(tǒng) </p><p> ?。?)智能化數(shù)字伺服驅(qū)動(dòng)裝置 </p><p>  可以通過自動(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)獲得最佳的運(yùn)行。 </p><p>  二、機(jī)床數(shù)控化改造的必要性 </p><p>  2.1、微觀看改造的必要性 </

11、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)越性均來自數(shù)控系統(tǒng)所包含的計(jì)算機(jī)的威力。 </p><p>  2.1.1 可以加工出傳統(tǒng)機(jī)床加工不出來的曲線、曲面等復(fù)雜的零件。</p><p>  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)雜的曲線或曲面。 </p><

12、;p>  2.1.2 可以實(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)算機(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,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)得以自動(dòng)化,故被稱為實(shí)現(xiàn)了"柔性自動(dòng)化"。 </p><p>

13、  2.1.3 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"。 </p><p>  2.1.4 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)。 </p><p>  2.1.5 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)間無人看管加工。 </p><p>  2.1.6 由以上五條派生的好處。 </

14、p><p>  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)算機(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

15、技術(shù)和基礎(chǔ)技術(shù)。</p><p>  The engine bed numerical control transforms shallowly discusses </p><p>  First, numerical control system development brief history and tendency</p><p>  In 1946

16、was born in the world the first electronic accounting machine, this indicated the humanity created has been possible to strengthen and partially to replace the mental labor the tool. It with the humanity these which in t

17、he 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 the humanity to lay the foundation. </p><

18、;p>  After 6 years, namely in 1952, computer technology applied to the engine bed on, were born the first numerical control engine bed in US. From this time on, the traditional engine bed has had the archery target ch

19、ange. Since nearly half century, the numerical control system has experienced two stages and six generation of development. </p><p>  1.1st, numerical control (NC) stage (1,952 ~ in 1970) </p><p&g

20、t;  The early computer operating speed is 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 l

21、ogic circuit "to build" to become an engine bed special purpose computer to take the numerical control system, is called the hardware connection numerical control (HARD-WIRED NC), Jian Chengwei numerical contro

22、l (NC). Along with the primary device development, this stage has had been</p><p>  1.2nd, computer numerical control (CNC) stage (in 1970 ~ present) </p><p>  To 1970, the general minicomputer

23、already appeared and the mass production. Thereupon transplants it takes the numerical control system the core part, from this time on entered the computer numerical control (CNC) the stage ("which should have compu

24、ter in front of the general" two characters to abbreviate). To 1971, American INTEL Corporation in the world first time the computer two most cores part -- logic units and the controller, used the large scale integr

25、ated circuit technology integration </p><p>  The microprocessor is applied to 1974 in the numerical control system. This is because minicomputer function too strong, controlled an engine bed ability to have

26、 wealthily (therefore once uses in controlling the multi- Taiwan engine bed at that time, called it group control), was inferior to used the microprocessor economy to be reasonable. Moreover then small machine reliabilit

27、y was not ideal. The early microprocessor speed and the function although insufficiently are also high, but may solve t</p><p>  To in 1990, PC machine (personal computer, domestic custom had called microcom

28、puter) the performance has developed to the very high stage, may satisfiedly take the numerical control system core part the request. The numerical control system henceforth entered based on the PC stage. </p><

29、;p>  In brief, the computer numerical control stage has also experienced three generations. Namely 1970 fourth generation of -- minicomputer; 1974 five dynasties -- microprocessor and 1990 sixth generation -- (oversea

30、s was called PC-BASED) based on PC. </p><p>  Also must point out, although overseas already renamed as the computer numerical control (namely CNC), but our country still the custom called the numerical cont

31、rol (NC). Therefore we daily say "numerical control", the materially already was refers to "computer numerical control". </p><p>  1.3rd, the numerical control future will develop tendenc

32、y </p><p>  1.3.1 open style continues to, to develop based on the PC sixth generation of direction </p><p>  Open, the low cost, redundant reliable, the software and hardware resources has whic

33、h based on PC are rich and so on the characteristic, the more numerical controls serial production factory can step onto this path. Uses PC machine to take at least its front end machine, processes question and so on man

34、-machine contact surface, programming, networking correspondence, undertakes the numerical control duty by the original system. PC machine has the friendly man-machine contact surface, will popula</p><p>  1

35、.3.2 approaches 高速化 and the high accuracy development </p><p>  This is adapts the engine bed to be high speed and the high accuracy direction need to develop. </p><p>  1.3.3 develops to the in

36、tellectualized direction </p><p>  Along with the artificial intelligence in the computer domain unceasing seepage and the development, the numerical control system intellectualized degree unceasingly will e

37、nhance. </p><p>  (1) applies the adaptive control technology </p><p>  The numerical control system can examine in the process some important information, and the automatic control system relat

38、ed parameter, achieves the improvement system running status the goal. </p><p>  (2) introduces the expert system instruction processing </p><p>  The skilled worker and expert's experience,

39、 the processing general rule and the special rule store in the system, take the craft parameter database as the strut, the establishment has the artificial intelligence the expert system. </p><p>  (3) intro

40、duces the breakdown to diagnose the expert system </p><p>  (4) intellectualized numeral servo drive </p><p>  May through the automatic diagnosis load, but the automatic control parameter, caus

41、es the actuation system to obtain the best movement. </p><p>  Second, engine bed numerical control transformation necessity </p><p>  2.1st, microscopic looks at the transformation the necessit

42、y </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 mig

43、ht which the numerical control system contains. </p><p>  2.1.1 may process the traditional engine bed cannot process the curve, the curved surface and so on the complex components.</p><p>  Bec

44、ause the computer has the excellent 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

45、complex curve or the curved surface. </p><p>  2.1.2 may realize the processing automation, moreover is the flexible automation, thus the efficiency may enhance 3 ~ 7 times compared to the traditional engine

46、 bed. </p><p>  Because the 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

47、, thus realization automation. The numerical 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 aut

48、omate, therefore is called has realized "flexible automation". </p><p>  2.1.3 processings components precision high, size dispersion degree small, makes the assembly to be easy, no longer needs &q

49、uot;to make repairs". </p><p>  2.1.4 may realize the multi- working procedures centralism, reduces the components in engine bed between frequent transporting. </p><p>  2.1.5 has auto-alar

50、m, the automatic monitoring, automatic compensation and so on the many kinds of autonomy function, thus may realize long time nobody to safeguard the processing. </p><p>  2.1.6 advantage which derives by ab

51、ove five. </p><p>  For example: Reduced worker's labor intensity, saved the labor force (a person to be possible to safeguard the multi- Taiwan engine bed), reduced the work clothes, reduced the new pro

52、duct trial manufacturing cycle and the production cycle, might to the market demand make rapid reaction and so on. </p><p>  Above these superiority are the predecessor cannot imagine, is an extremely signif

53、icant breakthrough. In addition, the engine bed numerical control carries out FMC (flexible manufacture unit), FMS (flexible manufacture system) as well as CIMS (computer integration manufacture system) and so on the ent

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