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2009屆學(xué)生畢業(yè)論文（設(shè)計(jì)） 存檔編號(hào)：__________
畢業(yè)論文外文翻譯
題目：數(shù)控技術(shù)及其產(chǎn)業(yè)發(fā)展
部 （系） 機(jī)械與建筑工程學(xué)部___
專 業(yè) 機(jī)械設(shè)計(jì)制造及其自動(dòng)化
姓 名 彭偉雄
學(xué) 號(hào) 20051503010109
指導(dǎo)教師 李 列
2009年 月 日
1. About numerical control system design development gauge
As noted previously, there are better commonability , flexibility , adaptability , expanding in the open numerical control system, countries such as U.S.A. , European Community and Japan ,etc. implement the strategic development plan one after another , carry on research and formulation of the systematic norm of structural numerical control of the open system (OMAC , OSACA , OSEC ), 3 of world heavy economy carry on the same science plan and standardize formulation nearly in a short time most, have indicated a new arrival of period of change of the technology of numerical control. Our country started research and formulation which standardized the frame of ONC numerical control system of China too in 2000.
2 .About the numerical control standard
The numerical control standard is a kind of trend of information-based development of manufacturing industry. Numerical control technology information exchange of 50 year born , to based on ISO6983 standard, adopt G , M code describes how processes, its essential characteristic faces the processing course, obviously, he can''t meet demands of high-speed development of the technology of modern numerical control more and more already. For this reason, studying and making a kind of new CNC system standard ISO14649 (STEP-NC ) in the world, its purpose is offering a kind of neutral mechanism not depending on the concrete system , can describe the unified data model in whole lifespan of the products , thus realize the whole manufacture process, and even the standardization of each industrial field product information.
The appearance of STEP-NC may be a revolution of the technical field of the numerical control, on development and even the whole manufacturing industry of the technology of numerical control , will exert a far-reaching influence. First of all, STEP-NC puts forward a kind of brand-new manufacture idea , in the traditional manufacture idea, NC processes the procedures to all concentrate on single computer. Under the new standard, NC procedure can be dispersed on Internet, this is exactly a direction of open , networked development of technology of numerical control. Secondly, STEP-NC numerical control system also can reduce , process (about 75% ) drawing , process procedure work out (about 35% ) time and process (about 50% ) time greatly.
At present, American-European countries pay much attention to the research of STEP-NC, Europe initiates IMS plan (1999.1.1- 2001.12.3 ) of STEP-NC. 20 CAD/CAM/CAPP/CNC users , manufacturers and academic organizations from Europe and Japan participated in this plan. STEP Tools Company of U.S.A. is a developer of the data interchange software of manufacturing industry in the global range, he has already developed and accused of the super model (Super Model ) of information exchange of machine tooling by counting, its goal is to describe all processing courses with the unified norm. Such new data interchange form has already been verified in allocating the SIEMENS , FIDIA and European OSACA-NC numerical control at present.
3．Pairs of basic estimations of technology and industry development of numerical control of our country
The technology of numerical control of our country started in 1958, the development course in the past 50 years can roughly be divided into 3 stages: The first stage is from 1958 to 1979, i.e. closed developing stage. In this stages, technology of foreign countries blockade and basic restriction of terms of our country, the development of the technology of numerical control is comparatively slow. During " Sixth Five-Year Plan Period " , " the Seventh Five-Year Plan Period " of the country in second stage and earlier stage in " the Eighth Five-Year Plan Period ", introduce technology , digest and assimilate, the stage of establishing the system of production domesticization arisesing tentatively. At this stage , because of reform and opening-up and national attention , and study the improvement of the development environment and international environment, research , development and all making considerable progress in production domesticization of the products of the technology of numerical control of our country. The third stage is that on the later stage in " the Eighth Five-Year Plan Period " of the country and during the " Ninth Five-Year Plan Period ", implement the research of industrialization , enter market competition stage. At this stage, made substantive progress in industrialization of the domestic numerical control equipment of our country. In " the Ninth Five-Year Plan " latter stage, domestic numerical control domestic market share of lathe reach 50% , mix domestic numerical control system (popular ) to up to 10%.
Review the development course in the past 50 years of technology of numerical control of our country, especially pass the brainstorm of 4 Five-Year Plans, all in all has made following achievements.
a. Have establish the foundation of the technical development of numerical control, has basically mastered the technology of modern numerical control. Our country know from numerical control system , servo urge , numerical control host computer , special plane and their basic of fittings basically already now, among them most technology have already possessed the foundation that is commercialized and developed , some technology has already, industrialization commercialized.
a.Have formed the industrial base of numerical control tentatively. In tackling key problems the foundation that the achievement and some technology commercialize , set up the systematic factories of numerical control with production capacity of batch such as numerical control of Central China , spaceflight numerical control etc.. Electrical machinery plant of Lanzhou, a batch of servo systems and first machine tool plant , first machine tool plant of Jinan of servo electrical machinery factory and Beijing ,etc. several numerical control host computer factories such as the numerical control in Central China. These factories have basically formed the numerical control industrial base of our country.
b.Have set up research of a numerical control, development , managerial talent''s basic team . Though has made considerable progress in research and development and industrialization of the technology of numerical control, but we will realize soberly, the research and development of the technology of advanced numerical control of our country, there is greater disparity between current situation and current demand of our country of engineering level especially in industrialization. Though very fast from longitudinal development to watch our country, horizontal until (contrast with foreign countries ) , the engineering level has disparity, there is disparity too in development speed in some aspects, i.e. the disparity of engineering level between some high-grade , precision and advanced numerical control equipment has the tendency to expand . Watch from world , estimate roughly as follows about the numerical control engineering level of our country and industrialization level.
a.On the engineering level, in probably backward 10- 1 years with the advanced level in foreign countries, it is bigger in high-quality precision and sophisticated technology.
b.At the industrialization level, the market share is low, the variety coverage rate is low, have not formed the large-scale production yet; Function part specialized level of production and form a complete set ability to be lower; Appearance quality is relatively poor; Dependability is not high,the commercialized intensity is insufficient; Not setting up one''s own brand effect yet in domestic numerical control system, users have insufficient confidence.
c.At the ability of sustainable development, to competition numerical control research and development of technology, engineered ability weaker; Numerical control technological application expand efforts to be better; The research , formulation that relevant standards are normal lags behind.
It is analyzed that the main reason for having disparity described above has the following several respect.
a.Realize the respect. Know to domestic numerical control industry process arduousness , complexity and long-term characteristic insufficiently; One that is to market unstandard, foreign blockade add strangle , system ,etc. underestimate while being difficult; It is not enough to analyze to technological application level and ability of numerical control of our country.
b.System. Pay close attention to numerical control industrialization many in the issue , consider numerical control industrialization little in the issue synthetically in terms of the systematic one , industry chain in terms of technology; Set up intact related system , complete training , service network ,etc. of high quality support the system.
c.Mechanism. The bad mechanism causes the brain drain , restraining technology and technological route from innovating again , products innovation, and has restricted the effective implementation of planning , has often planned the ideal , implement the difficulty. d.Technology. Enterprises are indifferent in autonomous innovation in technology, key technology is engineered and indifferent. Lathe standard lag behind, level relatively low, numerical control system new standard study enoughly.
4. Strategic thinking until technology and industrialization of numerical control of our country develop
4.1 Strategic consideration
Our country of strategic consideration makes the big country , should try hard to accept the front instead of the back transformation in the world industry shifts , should master and make key technology advancedly , otherwise in a new round of international industrial structure adjustment, of our country manufacturing industry step forward " the empty core ". We regard resource , environment , market as cost, possibility got to exchange " assemble the centre ", but not master the status of the manufacturing center of key technology , will so influence the development process of the modern manufacturing industry of our country seriously.
We should stand in the height of national security strategy paying attention to the technology of numerical control and industry''s question , at first seen from social safety, because manufacturing industry whether our country obtain employment most populous trade, the development of manufacturing industry not only can improve the people''s living standard but also can relieve the pressure of employment of our country , ensure the stability of the society; Secondly seen from security of national defence, the western developed country has classified all the high-grade , precision and advanced numerical control products as the strategic materials of the country, realize embargo and restriction to our country, " Toshiba incident " and " Cox Report " is the best illustration.
4.2 Development tactics
Proceed from the angles of the fundamental realities of the country of our country, regard the strategic demand of the country and market demand of the national economy as the direction, regard improving our country and making the comprehensive competitive power of equipping industry and industrialization level as the goal, use the systematic method , be able to choose the support technology that the initial our country makes the key technology upgraded in development of equipping industry and supports the development of industrialization in 21st century of leading factor, the ability to supply the necessary technology realizes making the jump type development of the equipping industry as the content of research and development.
Emphasize market demand is a direction, take terminal products of numerical control as the core , with the complete machine (Such as the numerical control lathe having a large capacity and a wide range, milling machine , high speed high precise high-performance numerical control lathe , model digitized machinery , key industry key equipment ,etc. ) drive numerical control development of industry. Solve the numerical control system and relevant functions part especially The dependability in (digitized servo system and electrical machinery , electric main shaft system of high speed and new attachment that equip ,etc. ) and production scale question. There are no products without high dependability of scale ; Will not have cheap and products rich in the competitiveness without scale ; Certainly, it is difficult finally to have the day to hold up head that there is no Chinese numerical control equipment of scale .
In equipping researching and developing high-grade , precision and advancedly , should emphasize the production, learning and research and close combination of end user, regard " obtaining, using, selling " as the goal, tackle key problems according to the national will, in order to solve the needing badly of the country. The technology of numerical control, emphasized innovation, put emphasis on researching and developing technology and products with independent intellectual property right before the competition, establish the foundation for the numerical control industry of our country , sustainable development of the equipment manufacture and even the whole manufacturing industry.
1.關(guān)于數(shù)控系統(tǒng)設(shè)計(jì)開發(fā)規(guī)范
開放式數(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)期的來臨。我國(guó)在2000年也開始進(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)特征是面向加工過程，顯然，他已越來越不能滿足現(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（STEP－NC)，其目的是提供一種不依賴于具體系統(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(1999.1.1～2001.12.31)。參加這項(xiàng)計(jì)劃的有來自歐洲和日本的20個(gè)CAD/CAM/CAPP/CNC用戶、廠商和學(xué)術(shù)機(jī)構(gòu)。美國(guó)的STEPTools公司是全球范圍內(nèi)制造業(yè)數(shù)據(jù)交換軟件的開發(fā)者，他已經(jīng)開發(fā)了用作數(shù)控機(jī)床加工信息交換的超級(jí)模型(SuperModel)，其目標(biāo)是用統(tǒng)一的規(guī)范描述所有加工過程。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。
3.對(duì)我國(guó)數(shù)控技術(shù)及其產(chǎn)業(yè)發(fā)展的基本估計(jì)
我國(guó)數(shù)控技術(shù)起步于1958年，近50年的發(fā)展歷程大致可分為3個(gè)階段：第一階段從1958年到1979年，即封閉式發(fā)展階段。在此階段，由于國(guó)外的技術(shù)封鎖和我國(guó)的基礎(chǔ)條件的限制，數(shù)控技術(shù)的發(fā)展較為緩慢。第二階段是在國(guó)家的“六五”、“七五”期間以及“八五”的前期，即引進(jìn)技術(shù)，消化吸收，初步建立起國(guó)產(chǎn)化體系階段。在此階段，由于改革開放和國(guó)家的重視，以及研究開發(fā)環(huán)境和國(guó)際環(huán)境的改善，我國(guó)數(shù)控技術(shù)的研究、開發(fā)以及在產(chǎn)品的國(guó)產(chǎn)化方面都取得了長(zhǎng)足的進(jìn)步。第三階段是在國(guó)家的“八五”的后期和“九五”期間，即實(shí)施產(chǎn)業(yè)化的研究，進(jìn)入市場(chǎng)競(jìng)爭(zhēng)階段。在此階段，我國(guó)國(guó)產(chǎn)數(shù)控裝備的產(chǎn)業(yè)化取得了實(shí)質(zhì)性進(jìn)步。在“九五”末期，國(guó)產(chǎn)數(shù)控機(jī)床的國(guó)內(nèi)市場(chǎng)占有率達(dá)50％，配國(guó)產(chǎn)數(shù)控系統(tǒng)（普及型）也達(dá)到了10％。
縱觀我國(guó)數(shù)控技術(shù)近50年的發(fā)展歷程，特別是經(jīng)過4個(gè)5年計(jì)劃的攻關(guān)，總體來看取得了以下成績(jī)。
a.奠定了數(shù)控技術(shù)發(fā)展的基礎(chǔ)，基本掌握了現(xiàn)代數(shù)控技術(shù)。我國(guó)現(xiàn)在已基本掌握了從數(shù)控系統(tǒng)、伺服驅(qū)動(dòng)、數(shù)控主機(jī)、專機(jī)及其配套件的基礎(chǔ)技術(shù)，其中大部分技術(shù)已具備進(jìn)行商品化開發(fā)的基礎(chǔ)，部分技術(shù)已商品化、產(chǎn)業(yè)化。
b.初步形成了數(shù)控產(chǎn)業(yè)基地。在攻關(guān)成果和部分技術(shù)商品化的基礎(chǔ)上，建立了諸如華中數(shù)控、航天數(shù)控等具有批量生產(chǎn)能力的數(shù)控系統(tǒng)生產(chǎn)廠。蘭州電機(jī)廠、華中數(shù)控等一批伺服系統(tǒng)和伺服電機(jī)生產(chǎn)廠以及北京第一機(jī)床廠、濟(jì)南第一機(jī)床廠等若干數(shù)控主機(jī)生產(chǎn)廠。這些生產(chǎn)廠基本形成了我國(guó)的數(shù)控產(chǎn)業(yè)基地。
c.建立了一支數(shù)控研究、開發(fā)、管理人才的基本隊(duì)伍。
雖然在數(shù)控技術(shù)的研究開發(fā)以及產(chǎn)業(yè)化方面取得了長(zhǎng)足的進(jìn)步，但我們也要清醒地認(rèn)識(shí)到，我國(guó)高端數(shù)控技術(shù)的研究開發(fā)，尤其是在產(chǎn)業(yè)化方面的技術(shù)水平現(xiàn)狀與我國(guó)的現(xiàn)實(shí)需求還有較大的差距。雖然從縱向看我國(guó)的發(fā)展速度很快，但橫向比（與國(guó)外對(duì)比）不僅技術(shù)水平有差距，在某些方面發(fā)展速度也有差距，即一些高精尖的數(shù)控裝備的技術(shù)水平差距有擴(kuò)大趨勢(shì)。從國(guó)際上來看，對(duì)我國(guó)數(shù)控技術(shù)水平和產(chǎn)業(yè)化水平估計(jì)大致如下。
a.技術(shù)水平上，與國(guó)外先進(jìn)水平大約落后10～15年，在高精尖技術(shù)方面則更大。
b.產(chǎn)業(yè)化水平上，市場(chǎng)占有率低，品種覆蓋率小，還沒有形成規(guī)模生產(chǎn)；功能部件專業(yè)化生產(chǎn)水平及成套能力較低；外觀質(zhì)量相對(duì)差；可靠性不高，商品化程度不足；國(guó)產(chǎn)數(shù)控系統(tǒng)尚未建立自己的品牌效應(yīng)，用戶信心不足。
c.可持續(xù)發(fā)展的能力上，對(duì)競(jìng)爭(zhēng)前數(shù)控技術(shù)的研究開發(fā)、工程化能力較弱；數(shù)控技術(shù)應(yīng)用領(lǐng)域拓展力度不強(qiáng)；相關(guān)標(biāo)準(zhǔn)規(guī)范的研究、制定滯后。
分析存在上述差距的主要原因有以下幾個(gè)方面。
a.認(rèn)識(shí)方面。對(duì)國(guó)產(chǎn)數(shù)控產(chǎn)業(yè)進(jìn)程艱巨性、復(fù)雜性和長(zhǎng)期性的特點(diǎn)認(rèn)識(shí)不足；對(duì)市場(chǎng)的不規(guī)范、國(guó)外的封鎖加扼殺、體制等困難估計(jì)不足；對(duì)我國(guó)數(shù)控技術(shù)應(yīng)用水平及能力分析不夠。
b.體系方面。從技術(shù)的角度關(guān)注數(shù)控產(chǎn)業(yè)化問題的時(shí)候多，從系統(tǒng)的、產(chǎn)業(yè)鏈的角度綜合考慮數(shù)控產(chǎn)業(yè)化問題的時(shí)候少；沒有建立完整的高質(zhì)量的配套體系、完善的培訓(xùn)、服務(wù)網(wǎng)絡(luò)等支撐體系。
c.機(jī)制方面。不良機(jī)制造成人才流失，又制約了技術(shù)及技術(shù)路線創(chuàng)新、產(chǎn)品創(chuàng)新，且制約了規(guī)劃的有效實(shí)施，往往規(guī)劃理想，實(shí)施困難。
d.技術(shù)方面。企業(yè)在技術(shù)方面自主創(chuàng)新能力不強(qiáng)，核心技術(shù)的工程化能力不強(qiáng)。機(jī)床標(biāo)準(zhǔn)落后，水平較低，數(shù)控系統(tǒng)新標(biāo)準(zhǔn)研究不夠。
4.對(duì)我國(guó)數(shù)控技術(shù)和產(chǎn)業(yè)化發(fā)展的戰(zhàn)略思考
4.1戰(zhàn)略考慮
我國(guó)是制造大國(guó)，在世界產(chǎn)業(yè)轉(zhuǎn)移中要盡量接受前端而不是后端的轉(zhuǎn)移，即要掌握先進(jìn)制造核心技術(shù)，否則在新一輪國(guó)際產(chǎn)業(yè)結(jié)構(gòu)調(diào)整中，我國(guó)制造業(yè)將進(jìn)一步“空芯”。我們以資源、環(huán)境、市場(chǎng)為代價(jià)，交換得到的可能僅僅是世界新經(jīng)濟(jì)格局中的國(guó)際“加工中心”和“組裝中心”，而非掌握核心技術(shù)的制造中心的地位，這樣將會(huì)嚴(yán)重影響我國(guó)現(xiàn)代制造業(yè)的發(fā)展進(jìn)程。
我們應(yīng)站在國(guó)家安全戰(zhàn)略的高度來重視數(shù)控技術(shù)和產(chǎn)業(yè)問題，首先從社會(huì)安全看，因?yàn)橹圃鞓I(yè)是我國(guó)就業(yè)人口最多的行業(yè)，制造業(yè)發(fā)展不僅可提高人民的生活水平，而且還可緩解我國(guó)就業(yè)的壓力，保障社會(huì)的穩(wěn)定；其次從國(guó)防安全看，西方發(fā)達(dá)國(guó)家把高精尖數(shù)控產(chǎn)品都列為國(guó)家的戰(zhàn)略物質(zhì)，對(duì)我國(guó)實(shí)現(xiàn)禁運(yùn)和限制，“東芝事件”和“考克斯報(bào)告”就是最好的例證。
4.2發(fā)展策略
從我國(guó)基本國(guó)情的角度出發(fā)，以國(guó)家的戰(zhàn)略需求和國(guó)民經(jīng)濟(jì)的市場(chǎng)需求為導(dǎo)向，以提高我國(guó)制造裝備業(yè)綜合競(jìng)爭(zhēng)能力和產(chǎn)業(yè)化水平為目標(biāo)，用系統(tǒng)的方法，選擇能夠主導(dǎo)21世紀(jì)初期我國(guó)制造裝備業(yè)發(fā)展升級(jí)的關(guān)鍵技術(shù)以及支持產(chǎn)業(yè)化發(fā)展的支撐技術(shù)、配套技術(shù)作為研究開發(fā)的內(nèi)容，實(shí)現(xiàn)制造裝備業(yè)的跨躍式發(fā)展。
強(qiáng)調(diào)市場(chǎng)需求為導(dǎo)向，即以數(shù)控終端產(chǎn)品為主，以整機(jī)（如量大面廣的數(shù)控車床、銑床、高速高精高性能數(shù)控機(jī)床、典型數(shù)字化機(jī)械、重點(diǎn)行業(yè)關(guān)鍵設(shè)備等）帶動(dòng)數(shù)控產(chǎn)業(yè)的發(fā)展。重點(diǎn)解決數(shù)控系統(tǒng)和相關(guān)功能部件（數(shù)字化伺服系統(tǒng)與電機(jī)、高速電主軸系統(tǒng)和新型裝備的附件等）的可靠性和生產(chǎn)規(guī)模問題。沒有規(guī)模就不會(huì)有高可靠性的產(chǎn)品；沒有規(guī)模就不會(huì)有價(jià)格低廉而富有競(jìng)爭(zhēng)力的產(chǎn)品；當(dāng)然，沒有規(guī)模中國(guó)的數(shù)控裝備最終難以有出頭之日。
在高精尖裝備研發(fā)方面，要強(qiáng)調(diào)產(chǎn)、學(xué)、研以及最終用戶的緊密結(jié)合，以“做得出、用得上、賣得掉”為目標(biāo)，按國(guó)家意志實(shí)施攻關(guān)，以解決國(guó)家之急需。
在競(jìng)爭(zhēng)前數(shù)控技術(shù)方面，強(qiáng)調(diào)創(chuàng)新，強(qiáng)調(diào)研究開發(fā)具有自主知識(shí)產(chǎn)權(quán)的技術(shù)和產(chǎn)品，為我國(guó)數(shù)控產(chǎn)業(yè)、裝備制造業(yè)乃至整個(gè)制造業(yè)的可持續(xù)發(fā)展奠定基礎(chǔ)。
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