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無(wú)錫職業(yè)技術(shù)學(xué)院畢業(yè)設(shè)計(jì)說(shuō)明書(shū)數(shù)控技術(shù)數(shù)控技術(shù)，簡(jiǎn)稱(chēng)“數(shù)控”。英文：Numerical Control（NC）。是指用數(shù)字、文字和符號(hào)組成的數(shù)字指令來(lái)實(shí)現(xiàn)一臺(tái)或多臺(tái)機(jī)械設(shè)備動(dòng)作控制的技術(shù)。它所控制的通常 是位置、角度、速度等機(jī)械量和與機(jī)械能量流向有關(guān)的開(kāi)關(guān)量。數(shù)控的產(chǎn)生依賴(lài)于數(shù)據(jù)載體和二進(jìn)制形式數(shù)據(jù)運(yùn)算的出現(xiàn)。1908年，穿孔的金屬薄片互換式數(shù)據(jù)載體問(wèn)世；19世紀(jì)末，以紙為數(shù)據(jù)載體并具有輔助功能的控制系統(tǒng)被發(fā)明；1938年，香農(nóng)在美國(guó)麻省理工學(xué)院進(jìn)行了數(shù)據(jù)快速運(yùn)算和傳輸，奠定了現(xiàn)代計(jì)算機(jī)，包括計(jì)算機(jī)數(shù)字控制系統(tǒng)的基礎(chǔ)。數(shù)控技術(shù)是與機(jī)床控制密切結(jié)合發(fā)展起來(lái)的。1952年，第一臺(tái)數(shù)控機(jī)床問(wèn)世，成為世界機(jī)械工業(yè)史上一件劃時(shí)代的事件，推動(dòng)了自動(dòng)化的發(fā)展。 現(xiàn)在，數(shù)控技術(shù)也叫計(jì)算機(jī)數(shù)控技術(shù)，目前它是采用計(jì)算機(jī)實(shí)現(xiàn)數(shù)字程序控制的技術(shù)。這種技術(shù)用計(jì)算機(jī)按事先存貯的控制程序來(lái)執(zhí)行對(duì)設(shè)備的控制功能。由于采用計(jì)算機(jī)替代原先用硬件邏輯電路組成的數(shù)控裝置，使輸入數(shù)據(jù)的存貯、處理、運(yùn)算、邏輯判斷等各種控制機(jī)能的實(shí)現(xiàn)，均可以通過(guò)計(jì)算機(jī)軟件來(lái)完成。 數(shù)控技術(shù)的應(yīng)用不但給傳統(tǒng)制造業(yè)帶來(lái)了革命性的變化，使制造業(yè)成為工業(yè)化的象征，而且隨著數(shù)控技術(shù)的不斷發(fā)展和應(yīng)用領(lǐng)域的擴(kuò)大，他對(duì)國(guó)計(jì)民生的一些重要行業(yè)（IT、汽車(chē)、輕工、醫(yī)療等）的發(fā)展起著越來(lái)越重要的作用，因?yàn)檫@些行業(yè)所需裝備的數(shù)字化已是現(xiàn)代發(fā)展的大趨勢(shì)。從目前世界上數(shù)控技術(shù)及其裝備發(fā)展的趨勢(shì)來(lái)看，其主要研究熱點(diǎn)有以下幾個(gè)方面。 1.高速、高精加工技術(shù)及裝備的新趨勢(shì) 效率、質(zhì)量是先進(jìn)制造技術(shù)的主體。高速、高精加工技 術(shù)可極大地提高效率，提高產(chǎn)品的質(zhì)量和檔次，縮短生產(chǎn)周期和提高市場(chǎng)競(jìng)爭(zhēng)能力。為此日本先端技術(shù)研究會(huì)將其列為5大現(xiàn)代制造技術(shù)之一，國(guó)際生產(chǎn)工程學(xué)會(huì)（CIRP）將其確定為21世紀(jì)的中心研究方向之一。 在轎車(chē)工業(yè)領(lǐng)域，年產(chǎn)30萬(wàn)輛的生產(chǎn)節(jié)拍是40秒/輛，而且多品種加工是轎車(chē)裝備必須解決的重點(diǎn)問(wèn)題之一；在航空和宇航工業(yè)領(lǐng)域，其加工的零部件多為薄壁和薄筋，剛度很差，材料為鋁或鋁合金，只有在高切削速度和切削力很小的情況下，才能對(duì)這些筋、壁進(jìn)行加工。近來(lái)采用大型整體鋁合金坯料“掏空”的方法來(lái)制造機(jī)翼、機(jī)身等大型零件來(lái)替代多個(gè)零件通過(guò)眾多的鉚釘、螺釘和其他聯(lián)結(jié)方式拼裝，使構(gòu)件的強(qiáng)度、剛度和可靠性得到提高。這些都對(duì)加工裝備提出了高速、高精和高柔性的要求。 從EMO2001展會(huì)情況來(lái)看，高速加工中心進(jìn)給速度可達(dá)80m/min，甚至更高，空運(yùn)行速度可達(dá)100m/min左右。目前世界上許多汽車(chē)廠(chǎng)，包括我國(guó)的上海通用汽車(chē)公司，已經(jīng)采用以高速加工中心組成的生產(chǎn)線(xiàn)部分替代組合機(jī)床。美國(guó)CINCINNATI公司的HyperMach機(jī)床進(jìn)給速度最大達(dá)60m/min，快速為100m/min，加速度達(dá)2g，主軸轉(zhuǎn)速已達(dá)60000r/min。加工一薄壁飛機(jī)零件，只用30min，而同樣的零件在一般高速銑床加工需3h，在普通銑床加工需8h；德國(guó)DMG公司的雙主軸車(chē)床的主軸速度及加速度分別達(dá)12*!000r/mm和1g。 在加工精度方面，近10年來(lái)，普通級(jí)數(shù)控機(jī)床的加工精度已由10m提高到5m，精密級(jí)加工中心則從35m，提高到11.5m，并且超精密加工精度已開(kāi)始進(jìn)入納米級(jí)(0.01m)。 在可靠性方面，國(guó)外數(shù)控裝置的MTBF值已達(dá)6 000h以上 ，伺服系統(tǒng)的MTBF值達(dá)到30000h以上，表現(xiàn)出非常高的可靠性。 為了實(shí)現(xiàn)高速、高精加工，與之配套的功能部件如電主軸、直線(xiàn)電機(jī)得到了快速的發(fā)展，應(yīng)用領(lǐng)域進(jìn)一步擴(kuò)大。 2. 5軸聯(lián)動(dòng)加工和復(fù)合加工機(jī)床快速發(fā)展 采用5軸聯(lián)動(dòng)對(duì)三維曲面零件的加工，可用刀具最佳幾何形狀進(jìn)行切削，不僅光潔度高，而且效率也大幅度提高。一般認(rèn)為，1臺(tái)5軸聯(lián)動(dòng)機(jī)床的效率可以等于2臺(tái)3軸聯(lián)動(dòng)機(jī)床，特別是使用立方氮化硼等超硬材料銑刀進(jìn)行高速銑削淬硬鋼零件時(shí)，5軸聯(lián)動(dòng)加工可比3軸聯(lián)動(dòng)加工發(fā)揮更高的效益。但過(guò)去因5軸聯(lián)動(dòng)數(shù)控系統(tǒng)、主機(jī)結(jié)構(gòu)復(fù)雜等原因，其價(jià)格要比3軸聯(lián)動(dòng)數(shù)控機(jī)床高出數(shù)倍，加之編程技術(shù)難度較大，制約了5軸聯(lián)動(dòng)機(jī)床的發(fā)展。 當(dāng)前由于電主軸的出現(xiàn)，使得實(shí)現(xiàn)5軸聯(lián)動(dòng)加工的復(fù)合主軸頭結(jié)構(gòu)大為簡(jiǎn)化，其制造難度和成本大幅度降低，數(shù)控系統(tǒng)的價(jià)格差距縮小。因此促進(jìn)了復(fù)合主軸頭類(lèi)型5軸聯(lián)動(dòng)機(jī)床和復(fù)合加工機(jī)床（含5面加工機(jī)床）的發(fā)展。 在EMO2001展會(huì)上，新日本工機(jī)的5面加工機(jī)床采用復(fù)合主軸頭，可實(shí)現(xiàn)4個(gè)垂直平面的加工和任意角度的加工，使得5面加工和5軸加工可在同一臺(tái)機(jī)床上實(shí)現(xiàn)，還可實(shí)現(xiàn)傾斜面和倒錐孔的加工。德國(guó)DMG公司展出DMUVoution系列加工中心，可在一次裝夾下5面加工和5軸聯(lián)動(dòng)加工，可由CNC系統(tǒng)控制或CAD/CAM直接或間接控制。 3. 智能化、開(kāi)放式、網(wǎng)絡(luò)化成為當(dāng)代數(shù)控系統(tǒng)發(fā)展的主要趨勢(shì) 21世紀(jì)的數(shù)控裝備將是具有一定智能化的系統(tǒng)，智能化的內(nèi)容包括在數(shù)控系統(tǒng)中的各個(gè)方面：為追求加工效率和加工質(zhì)量方面的智能化，如加工過(guò)程的自適應(yīng)控制，工藝參數(shù)自動(dòng)生成；為提高驅(qū)動(dòng)性能及使用連接方便的智能化，如前饋控制、電機(jī)參數(shù)的自適應(yīng)運(yùn)算、自動(dòng)識(shí)別負(fù)載自動(dòng)選定模型、自整定等；簡(jiǎn)化編程、簡(jiǎn)化操作方面的智能化，如智能化的自動(dòng)編程、智能化的人機(jī)界面等；還有智能診斷、智能監(jiān)控方面的內(nèi)容、方便系統(tǒng)的診斷及維修等。 為解決傳統(tǒng)的數(shù)控系統(tǒng)封閉性和數(shù)控應(yīng)用軟件的產(chǎn)業(yè)化生產(chǎn)存在的問(wèn)題。目前許多國(guó)家對(duì)開(kāi)放式數(shù)控系統(tǒng)進(jìn)行研究，如美國(guó)的NGC(The Next Generation Work-Station/Machine Control)、歐共體的OSACA(Open System Architecture for Control within Automation Systems)、日本的OSEC(Open System Environment for Controller)，中國(guó)的ONC(Open Numerical Control System)等。數(shù)控系統(tǒng)開(kāi)放化已經(jīng)成為數(shù)控系統(tǒng)的未來(lái)之路。所謂開(kāi)放式數(shù)控系統(tǒng)就是數(shù)控系統(tǒng)的開(kāi)發(fā)可以在統(tǒng)一的運(yùn)行平臺(tái)上，面向機(jī)床廠(chǎng)家和最終用戶(hù)，通過(guò)改變、增加或剪裁結(jié)構(gòu)對(duì)象（數(shù)控功能），形成系列化，并可方便地將用戶(hù)的特殊應(yīng)用和技術(shù)訣竅集成到控制系統(tǒng)中，快速實(shí)現(xiàn)不同品種、不同檔次的開(kāi)放式數(shù)控系統(tǒng)，形成具有鮮明個(gè)性的名牌產(chǎn)品。目前開(kāi)放式數(shù)控系統(tǒng)的體系結(jié)構(gòu)規(guī)范、通信規(guī)范、配置規(guī)范、運(yùn)行平臺(tái)、數(shù)控系統(tǒng)功能庫(kù)以及數(shù)控系統(tǒng)功能軟件開(kāi)發(fā)工具等是當(dāng)前研究的核心。 網(wǎng)絡(luò)化數(shù)控裝備是近兩年國(guó)際著名機(jī)床博覽會(huì)的一個(gè)新亮點(diǎn)。數(shù)控裝備的網(wǎng)絡(luò)化將極大地滿(mǎn)足生產(chǎn)線(xiàn)、制造系統(tǒng)、制造企業(yè)對(duì)信息集成的需求，也是實(shí)現(xiàn)新的制造 模式如敏捷制造、虛擬企業(yè)、全球制造的基礎(chǔ)單元。國(guó)內(nèi)外一些著名數(shù)控機(jī)床和數(shù)控系統(tǒng)制造公司都在近兩年推出了相關(guān)的新概念和樣機(jī)，如在EMO2001展中，日本山崎馬扎克（Mazak)公司展出的“CyberProduction Center”（智能生產(chǎn)控制中心，簡(jiǎn)稱(chēng)CPC)；日本大隈（Okuma）機(jī)床公司展出“IT plaza”（信息技術(shù)廣場(chǎng)，簡(jiǎn)稱(chēng)IT廣場(chǎng))；德國(guó)西門(mén)子(Siemens)公司展出的Open Manufacturing Environment（開(kāi)放制造環(huán)境，簡(jiǎn)稱(chēng)OME）等，反映了數(shù)控機(jī)床加工向網(wǎng)絡(luò)化方向發(fā)展的趨勢(shì)。 4. 重視新技術(shù)標(biāo)準(zhǔn)、規(guī)范的建立 （1） 關(guān)于數(shù)控系統(tǒng)設(shè)計(jì)開(kāi)發(fā)規(guī)范 如前所述，開(kāi)放式數(shù)控系統(tǒng)有更好的通用性、柔性、適應(yīng)性、擴(kuò)展性，美國(guó)、歐共體和日本等國(guó)紛紛實(shí)施戰(zhàn)略發(fā)展計(jì)劃，并進(jìn)行開(kāi)放式體系結(jié)構(gòu)數(shù)控系統(tǒng)規(guī)范(OMAC、OSACA、OSEC)的研究和制定，世界3個(gè)最大的經(jīng)濟(jì)體在短期內(nèi)進(jìn)行了幾乎相同的科學(xué)計(jì)劃和規(guī)范的制定，預(yù)示了數(shù)控技術(shù)的一個(gè)新的變革時(shí)期的來(lái)臨。我國(guó)在2000年也開(kāi)始進(jìn)行中國(guó)的ONC數(shù)控系統(tǒng)的規(guī)范框架的研究和制定。 （2） 關(guān)于數(shù)控標(biāo)準(zhǔn) 數(shù)控標(biāo)準(zhǔn)是制造業(yè)信息化發(fā)展的一種趨勢(shì)。數(shù)控技術(shù)誕生后的50年間的信息交換都是基于ISO6983標(biāo)準(zhǔn)，即采用G，M代碼描述如何（how）加工，其本質(zhì)特征是面向加工過(guò)程，顯然，他已越來(lái)越不能滿(mǎn)足現(xiàn)代數(shù)控技術(shù)高速發(fā)展的需要。為此，國(guó)際上正在研究和制定一種新的CNC系統(tǒng)標(biāo)準(zhǔn)ISO14649（STEPNC)，其目的是提供一種不依賴(lài)于具體系統(tǒng)的中性機(jī)制，能夠描述產(chǎn)品整個(gè) 生命周期內(nèi)的統(tǒng)一數(shù)據(jù)模型，從而實(shí)現(xiàn)整個(gè)制造過(guò)程，乃至各個(gè)工業(yè)領(lǐng)域產(chǎn)品信息的標(biāo)準(zhǔn)化。 STEP-NC的出現(xiàn)可能是數(shù)控技術(shù)領(lǐng)域的一次革命，對(duì)于數(shù)控技術(shù)的發(fā)展乃至整個(gè)制造業(yè)，將產(chǎn)生深遠(yuǎn)的影響。首先，STEP-NC提出一種嶄新的制造理念，傳統(tǒng)的制造理念中，NC加工程序都集中在單個(gè)計(jì)算機(jī)上。而在新標(biāo)準(zhǔn)下，NC程序可以分散在互聯(lián)網(wǎng)上，這正是數(shù)控技術(shù)開(kāi)放式、網(wǎng)絡(luò)化發(fā)展的方向。其次，STEP-NC數(shù)控系統(tǒng)還可大大減少加工圖紙（約75）、加工程序編制時(shí)間（約35）和加工時(shí)間（約50）。 目前，歐美國(guó)家非常重視STEP-NC的研究，歐洲發(fā)起了STEP-NC的IMS計(jì)劃(1999.1.12001.12.31)。參加這項(xiàng)計(jì)劃的有來(lái)自歐洲和日本的20個(gè)CAD/CAM/CAPP/CNC用戶(hù)、廠(chǎng)商和學(xué)術(shù)機(jī)構(gòu)。美國(guó)的STEP Tools公司是全球范圍內(nèi)制造業(yè)數(shù)據(jù)交換軟件的開(kāi)發(fā)者，他已經(jīng)開(kāi)發(fā)了用作數(shù)控機(jī)床加工信息交換的超級(jí)模型(Super Model)，其目標(biāo)是用統(tǒng)一的規(guī)范描述所有加工過(guò)程。目前這種新的數(shù)據(jù)交換格式已經(jīng)在配備了SIEMENS、FIDIA以及歐洲OSACA-NC數(shù)控系統(tǒng)的原型樣機(jī)上進(jìn)行了驗(yàn)證。 編輯本段數(shù)控機(jī)床程序編制一.數(shù)控機(jī)床編程的方法 數(shù)控機(jī)床程序編制的方法有三種：即手工編程、自動(dòng)編程CAD/CAM 。 1. 手工編程 由人工完成零件圖樣分析、工藝處理、數(shù)值計(jì)算、書(shū)寫(xiě)程序清單直到程序的輸入和檢驗(yàn)。適用于點(diǎn)位加工或幾何形狀不太復(fù)雜的零件，但是，非常費(fèi)時(shí)，且編制復(fù)雜零件時(shí)，容易出錯(cuò)。 2. 自動(dòng)編程 使用計(jì)算機(jī)或程編機(jī)，完成零件程序的編制的過(guò)程，對(duì)于復(fù)雜的零件很方便。 3. CAD/CAM 利用CAD/CAM軟件，實(shí)現(xiàn)造型及圖象自動(dòng)編程。最為典型的軟件是Master CAM，其可以完成銑削二坐標(biāo)、三坐標(biāo)、四坐標(biāo)和五坐標(biāo)、車(chē)削、線(xiàn)切割的編程，此類(lèi)軟件雖然功能單一，但簡(jiǎn)單易學(xué)，價(jià)格較低，仍是目前中小企業(yè)的選擇。 二.數(shù)控機(jī)床程序編制的內(nèi)容和步驟 1. 數(shù)控機(jī)床編程的主要內(nèi)容 分析零件圖樣、確定加工工藝過(guò)程、進(jìn)行數(shù)學(xué)處理、編寫(xiě)程序清單、制作控制介質(zhì)、進(jìn)行程序檢查、輸入程序以及工件試切。 2. 數(shù)控機(jī)床的步驟 1) 分析零件圖樣和工藝處理 根據(jù)圖樣對(duì)零件的幾何形狀尺寸，技術(shù)要求進(jìn)行分析，明確加工的內(nèi)容及要求，決定加工方案、確定加工順序、設(shè)計(jì)夾具、選擇刀具、確定合理的走刀路線(xiàn)及選擇合理的切削用量等。 同時(shí)還應(yīng)發(fā)揮數(shù)控系統(tǒng)的功能和數(shù)控機(jī)床本身的能力，正確選擇對(duì)刀點(diǎn)，切入方式，盡量減少諸如換刀、轉(zhuǎn)位等輔助時(shí)間。 2) 數(shù)學(xué)處理 編程前，根據(jù)零件的幾何特征，先建立一個(gè)工件坐標(biāo)系， CNC Technology Numerical control technology, referred to as NC. English: Numerical Control (NC). Refers to numbers, text and symbols to achieve the number of instructions one or more motion control technology machinery and equipment. Usually it controls CNC Technology Is the position, angle, speed and other mechanical quantities and the mechanical energy of the flow switch. CNC production depends on the data carrier and the emergence of binary data operation. 1908, perforated metal sheet interchangeable data carriers come out; the 19th century, the paper carrier for data and control system with auxiliary functions to be invented; 1938, Shannon was at the Massachusetts Institute of fast computing and data transmission, basis of modern computers, including computer based digital control system. CNC technology is closely integrated with the machine control to develop. In 1952, the first CNC machine tools available, to become a landmark in the history of the worlds machinery industry events, and promoted the development of automation. CNC machine tools Now, digital technology, also known as computer numerical control technology, which is currently using the digital process control computer technology. This technique pre-stored by a computer control program to implement control functions on the device. As originally used by computer instead of NC hardware logic circuit device so that the input data storage, processing, computing, logic implementation of various control functions are done by computer software. Edit this paragraph CNC technology trends CNC technology not only to the traditional manufacturing industry has brought revolutionary changes to the manufacturing sector as a symbol of industrialization, and with the continuous development of numerical control technology and expansion of application fields, some of his national economy and major industries (IT, automotive , light industry, medical, etc.) plays an increasingly important role in the development, as these industries for the digital equipment is the major trend of modern development. CNC technology from the world development trend and its equipment, its main research focus in the following areas. 1. High-speed, high precision technology and equipment of the new trend Efficiency, quality is the subject of advanced manufacturing technology. High-speed, high precision technology CNC machine workflow Surgery can greatly improve efficiency, improve product quality and grade, shorten the production cycle and enhance market competitiveness. Japan carries the technology will be included as one of five great modern manufacturing technologies, International Institute of Production Engineering (CIRP) to determine the center of the 21st century research direction. In the car industry, with an annual production of 300,000 beat is 40 seconds / vehicle and car equipment variety processing is one of the key must be addressed; in the aviation and aerospace industry, and its processing for the thin-walled parts and more and thin muscle, stiffness is poor, the material is aluminum or aluminum alloy, high cutting speed and cutting force only in the case of a small can of these bars, wall processing. Recently, the whole aluminum alloy with large blank hollowed out approach to make wings, fuselage and other large part to replace multiple parts through a large number of rivets, screws and other assembly connection means, so that component strength, rigidity and dependability increased. These are made of processing equipment, high speed, high precision and high flexibility. Judging from the EMO2001 exhibition, high-speed machining center feed rate of up to 80m/min, or even higher, and air speed up to 100m/min so. Currently many of the world automobile plant, including Shanghai General Motors, have adopted high-speed machining center part of the production line of machine tool alternatives. CINCINNATI HyperMach U.S. companys largest machine tool feed speed up to 60m/min, quick to 100m/min, acceleration up to 2g, the spindle speed has reached 60000r/min. Aircraft parts machining a thin-walled, only 30min, and the same high-speed milling machine parts in general need to 3h, in the general milling machine to be 8h; Germanys dual-spindle lathe DMG spindle speed and acceleration of up to 12 *! 000r/mm and 1g. In the processing accuracy, the past 10 years, the general level of precision CNC machine tools increased from 10m to 5m, precision machining center from the 3 5m, increased to 1 1.5m, and ultra-precision machining has begun to enter the nano-scale precision (0.01m). In terms of reliability, MTBF values foreign numerical control device has reached more than 6 000h Composed of CNC machine tools Servo system MTBF value reached more than 30000h, showing very high reliability. In order to achieve high-speed, high precision, ancillary features such as spindle, linear motor has been the rapid development of application has been further expanded. 2.5-axis machining and rapid development of machine tool 5-axis machining of three-dimensional surface, can be the best geometry of the cutting tool, not only finish high, but efficiency is greatly improved. Generally believed that 1 5-axis machine tool efficiency can be equal to 2 sets 3 axis machine tools, particularly the use of cubic boron nitride and other superhard materials, high-speed milling of hardened steel cutter part, the 5-axis machining 3-axis than play a more effective process. But in the past due to 5-axis CNC system, the host structure of complex reasons, the price than the 3-axis NC machine tool several times higher, in addition to programming more difficult, limiting the development of 5-axis machine tools. The current emergence of the spindle, making the realization of the complex 5-axis simultaneous machining spindle head structure simplified, the manufacturing difficulty and costs significantly reduced, narrowing the gap between the price of CNC system. So for the first type of complex 5-axis spindle machine tools and machine tool (including 5-face machining) development. In EMO2001 exhibition, New Japan Engineering Machine 5-face machining of composite spindle head, can achieve four vertical plane processing and the processing of any angle, making the 5-sided machining and 5 axis machining can be implemented on the same machine, but also can be achieved and the inverted cone inclined plane processing. German companies exhibit DMUVoution series DMG machining center, a fixture in the next 5-sided machining and 5 axis joint NC Device Action processing, system control by the CNC or CAD / CAM controlled directly or indirectly. 3. Intelligent, open, network development as the major contemporary trends in numerical control system 21 numerical control equipment will be sure the intelligent system, intelligent content included in all aspects of the numerical control system: the pursuit of processing efficiency and processing quality of intelligence, such as the adaptive control process, process parameters automatically generation; to improve the performance and easy to use intelligent connection, such as feedforward control, adaptive computing motor parameters, automatic identification of load select models, self-tuning, etc.; simplify programming, simplifying operational aspects of intelligence, such as smart of automatic programming, intelligent man-machine interfaces; also intelligent diagnosis, intelligent control aspects, to facilitate system diagnostics and maintenance. CNC system to address the closure of the traditional CNC applications and industrial production problems. Many countries now open CNC system of research, such as the United States NGC (The Next Generation Work-Station/Machine Control), the EC OSACA (Open System Architecture for Control within Automation Systems), Japan OSEC (Open System Environment for Controller), China, ONC (Open Numerical Control System) and so on. Open CNC system has become a numerical control system of the future of the road. The so-called open-CNC system is CNC system development can be run in a unified platform, for the machine tool manufacturers and end users, by changing, adding or cutting out the structure object (NC function) to form a series, and easily to users special applications and technical know-how into the control system, rapid implementation of different varieties, different grades of open CNC system, the formation of a distinct brand personality. The open numerical control system architecture specification, communication specifications, configuration specifications, operating platform, function libraries and CNC numerical control system software development tools, system function is the core of the current study. Network numerical control equipment is well-known international machine tool fair the past two years, a new bright spot. NC network equipment will greatly satisfy the production lines, manufacturing systems, manufacturing information integration needs of enterprises, but also achieve new manufacturing CNC lathe Models such as agile manufacturing, virtual enterprises, global manufacturing the base unit. Some well-known at home and abroad, and CNC CNC machine tools manufacturing companies have introduced in recent years related to new concepts and prototype, as in EMO2001 exhibition, Japan Yamazaki Mazak (Mazak) that the company exhibits CyberProduction Center (intelligent production control center, referred to as CPC); Japan Okuma (Okuma) Machine Company exhibited IT plaza (Information Technology Square, referred to as IT Plaza); Germanys Siemens (Siemens) that the company exhibits Open Manufacturing Environment (open manufacturing environment, referred to as OME), etc. , reflecting the CNC machining direction to the network trend. 4. Emphasis on new technology standards, the establishment of norms (1) on the numerical control system design and development of norms As mentioned earlier, open CNC system has better versatility, flexibility, adaptability, scalability, the United States, the European Community and Japan have to implement the strategic development plan, and the open architecture CNC system specification (OMAC , OSACA, OSEC) research and development, the worlds three largest economies in the short term were almost the same as the scientific program and the standard formulation, indicating a numerical control technology, the advent of a new period of change. China also started in 2000, CNC Chinas regulatory framework ONC research and development. (2) on the NC Standard NC standard is the development of manufacturing information is a trend. CNC technology 50 years after the birth of the exchange of information is based on ISO6983 standards, which adopts the G, M code describes how (how) processing, the essential characteristics of process-oriented, obviously, he can not meet modern CNC technology high-speed development. To this end, the international research and development is a new CNC system standard ISO14649 (STEP-NC), the aim is to provide a specific system does not rely on a neutral mechanism to describe the entire product CNC milling machine Life cycle of the unified data model, enabling the entire manufacturing process, as well as various industry standardization of product information. STEP-NC may be the emergence of a revolution in the field of numerical control technology, the development of numerical control technology for the manufacturing sector as a whole, will have far-reaching impact. First, STEP-NC manufacturing presents a new concept, the concept of traditional manufacturing, NC machining program are concentrated in a single computer. Under the new standard, NC programs can be distributed on the Internet, which is open numerical control technology and network development. Secondly, STEP-NC CNC system can also reduce processing drawings (about 75%), processing the time (about 35%) and processing time (about 50%). At present, Europe and the United States attaches great importance to the research STEP-NC, the European launch of the IMS STEP-NC program (1999.1.1 2001.12.31). To participate in this program are from Europe and Japan 20 CAD / CAM / CAPP / CNC users, vendors and academic institutions. U.S. STEP Tools is a global exchange of data within the software development industry, he has developed for the exchange of information of CNC machining super model (Super Model), whose goal is a unified specification describes all the process. Such new data exchange format has been equipped with SIEMENS, FIDIA and the European OSACA-NC NC system is verified on the prototype. Edit this paragraph programming CNC machine tools One. CNC machine programming method CNC machine tool programming in three ways: the manual programming, automatic programming and Machi