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遼寧科技大學(xué)本科生畢業(yè)設(shè)計 第7 頁
The development trend of the numerical control technology
The engineering level of equipment industry and modernized intensity are determining the level of the whole national economy and modernized intensity , numerical control technology and equip , develop new developing new high-tech industry and most advanced industry To can make technology and basic equipment most (national defense industry industries , such as information technology and their industry , biotechnology , industry , aviation , spaceflight ,etc. ). Marx has ever said " the differences of different economic times, do not lie in what is produced, lie in how produce, with what means of labor produce ". Manufacturing technology and equipping the most basic means of production that are that the mankind produced the activity, and numerical control technology to equip most central technology. Nowadays the manufacturing industry all around the world adopts the technology of numerical control extensively; in order to improve manufacturing capacity and level, improve the adaptive capacity and competitive power to the changeable market of the trends. In addition every industrially developed country in the world also classifies the technology and numerical control equipment of numerical control as the strategic materials of the country, not merely take the great measure to develop one''s own numerical control technology and industry, and implement blockading and restrictive policy to our country in " high-grade, precision and advanced " key technology and equipment of numerical control. In a word, develop taking technology of numerical control as the core advanced manufacturing technology become world all developed country; accelerate economic development already in a more cost-effective manner, important route to improve the comprehensive national strength and national position.
Numerical control technology to go on technology that control with digital information to mechanical movement and working course, numerical control equipment whether represented by technology of numerical control new technology make industry and new developing infiltration electromechanics integrated product that form of manufacturing industry to tradition, i.e. what is called digitization equip, its technological range covers a lot of fields: (1)Mechanical manufacturing technology; (2)Information processing , processing , transmission technology; (3)Automatic control technology; (4)Servo drive technology; (5)Transducer technology; (6)Software engineering ,etc..
1 Development trend of a numerical control technology
The application of the technology of numerical control has not only brought the revolutionary change to traditional manufacturing industry, make the manufacturing industry become the industrialized symbol , and with the constant development of the technology of numerical control and enlargement of application, the development of he some important trades (IT , car , light industry , medical treatment ,etc. ) to the national economy and the people''s livelihood plays a more and more important role, because these trade necessary digitization that equipped has already been the main trend of modern development. According to the technology of numerical control and equipment development trend in the world at present, its main research focus has the following several respect [1~4].
1.1 A high-speed , high finish machining technology and new trend equipped
Efficiency, quality are subjects of the advanced manufacturing technology. At a high speed, high finish machining technology can raise the efficiency greatly, quality and grade to raise product, shorten production cycle and improve the competitive power of market. Japan carry technological research association classify their as one of the 5 loud modern manufacturing technologies first for this reason, learn (CIRP ) to confirm it as the centre in the 21st century to study one of the directions in international production engineering.
In machining accuracy, the past 10 years, ordinary progression accuse of machining accuracy of lathe raise to 5μm , from 3- 5μm accurate grades of machining center from 10μm already, improve to 1- 1.5μm, and the ultraprecision machining accuracy has already begun to enter nanometer (0.01μm )ly. In dependability, MTBF value of the foreign numerical control device has already reached above 6 000h, MTBF value of the servo system reaches above 30000h, demonstrate very high dependability . For realize at a high speed , high finish machining, related to it function part if electric main shaft , straight line electrical machinery get fast development, the application is further expanded .
1.2 5 axles link and process and compound and process the lathe to develop fast
Adopt 5 axle link , to three-dimensional curved surface processing of part , can cut with the best geometirc form of the cutter, not only highly polished, but also efficiency is improved by a large margin . It is generally acknowledged , a 5 axle gear beds of efficiency can equal 2 3 axle gear beds , use cubic nitrogen boron wait ultra hard material milling cutter go on at a high speed milling , sharpening , quenching hard steel at the part, 5 axle link , process constant 3 axle link , process , give play to high benefit. But go over because 5 axles link the numerical control system , complicated reason of host computer structure, price its link numerical control to be lathe several times higher than 3 axle, in addition programming technological difficulty relatively heavy , have restricted 5 axle gear beds of development. At present because of electric appearance of main shaft, make , realize 5 axle compound main shaft hair structure processed to link greatly simplify, it make difficulty and cost reduce by a large margin , numerical control price disparity of systems shrink. So promote compound main shaft head type 5 axle gear bed and compound development to process lathe (process the lathe including 5 ).
At EMO2001 exhibition, new Japanese 5 of worker machineprocess lathe adopt compound main shaft hair, can realize 4 processing and arbitrary processing of angle of vertical plane, make 5 process and 5 axles are processed and can be realized at the same lathe, can also realize the inclined plane and pour the processing of the hole of awls . Company , DMG of Germany , exhibit DMUVoution series machining center , can put , insert , down 5 process and 5 axes link and process in one, can be controlled by CNC system or CAD/CAM controls directly or indirectly.
1.3 intellectualizations, open style, the network turns into for the contemporary numerical control system development mainly hastens
The 21st century numerical control equipments will be has certain intellectualized the system, the intellectualized content including in numerical control system each aspect: In order to pursue the processing efficiency and the processing quality aspect intellectualization, like processing process adaptive control, craft parameter automatic production; In order to enhance the actuation performance and the use connection convenient intellectualization, like the feed-forward control, the electrical machinery parameter auto-adapted operation, the automatic diagnosis load automatic designation model, is automatic entire grades; Simplification programming, simplification operation aspect intellectualization, like intellectualized automatic programming, intellectualized man-machine contact surface and so on; Also has the intelligence to diagnose, the intelligent monitoring aspect content, the convenience system diagnosis and the service and so on
2pairs 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.
2 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.
b.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.
c.Have set up research of a numerical control, development , managerial talent''s basic team .
3 strategic thinking until technology and industrialization of numerical control of our country develop
3.1 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 ofour 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.
3.2 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.
遼寧科技大學(xué)本科生畢業(yè)設(shè)計（論文） 第12頁
數(shù)控技術(shù)的發(fā)展趨勢
裝備工業(yè)的技術(shù)水平和現(xiàn)代化程度決定著整個國民經(jīng)濟的水平和現(xiàn)代化程度，數(shù)控技術(shù)及裝備是發(fā)展新興高新技術(shù)產(chǎn)業(yè)和尖端工業(yè)（如信息技術(shù)及其產(chǎn)業(yè)、生物技術(shù)及其產(chǎn)業(yè)、航空、航天等國防工業(yè)產(chǎn)業(yè)）的使能技術(shù)和最基本的裝備。馬克思曾經(jīng)說過“各種經(jīng)濟時代的區(qū)別，不在于生產(chǎn)什么，而在于怎樣生產(chǎn)，用什么勞動資料生產(chǎn)”。制造技術(shù)和裝備就是人類生產(chǎn)活動的最基本的生產(chǎn)資料，而數(shù)控技術(shù)又是當(dāng)今先進制造技術(shù)和裝備最核心的技術(shù)。當(dāng)今世界各國制造業(yè)廣泛采用數(shù)控技術(shù)，以提高制造能力和水平，提高對動態(tài)多變市場的適應(yīng)能力和競爭能力。此外世界上各工業(yè)發(fā)達(dá)國家還將數(shù)控技術(shù)及數(shù)控裝備列為國家的戰(zhàn)略物資，不僅采取重大措施來發(fā)展自己的數(shù)控技術(shù)及其產(chǎn)業(yè)，而且在“高精尖”數(shù)控關(guān)鍵技術(shù)和裝備方面對我國實行封鎖和限制政策。總之，大力發(fā)展以數(shù)控技術(shù)為核心的先進制造技術(shù)已成為世界各發(fā)達(dá)國家加速經(jīng)濟發(fā)展、提高綜合國力和國家地位的重要途徑。
數(shù)控技術(shù)是用數(shù)字信息對機械運動和工作過程進行控制的技術(shù)，數(shù)控裝備是以數(shù)控技術(shù)為代表的新技術(shù)對傳統(tǒng)制造產(chǎn)業(yè)和新興制造業(yè)的滲透形成的機電一體化產(chǎn)品，即所謂的數(shù)字化裝備，其技術(shù)范圍覆蓋很多領(lǐng)域：(1)機械制造技術(shù)；(2)信息處理、加工、傳輸技術(shù)；(3)自動控制技術(shù)；(4)伺服驅(qū)動技術(shù)；(5)傳感器技術(shù)；(6)軟件技術(shù)等。
1數(shù)控技術(shù)的發(fā)展趨勢
數(shù)控技術(shù)的應(yīng)用不但給傳統(tǒng)制造業(yè)帶來了革命性的變化，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)域的擴大，他對國計民生的一些重要行業(yè)（IT、汽車、輕工、醫(yī)療等）的發(fā)展起著越來越重要的作用，因為這些行業(yè)所需裝備的數(shù)字化已是現(xiàn)代發(fā)展的大趨勢。從目前世界上數(shù)控技術(shù)及其裝備發(fā)展的趨勢來看，其主要研究熱點有以下幾個方面［1～4］。
1．1 高速、高精加工技術(shù)及裝備的新趨勢
效率、質(zhì)量是先進制造技術(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)周期和提高市場競爭能力。為此日本先端技術(shù)研究會將其列為5大現(xiàn)代制造技術(shù)之一，國際生產(chǎn)工程學(xué)會（CIRP）將其確定為21世紀(jì)的中心研究方向之一。
在加工精度方面，近10年來，普通級數(shù)控機床的加工精度已由10μm提高到5μm，精密級加工中心則從3～5μm，提高到1～1.5μm，并且超精密加工精度已開始進入納米級(0.01μm)。
在可靠性方面，國外數(shù)控裝置的MTBF值已達(dá)6000h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。
為了實現(xiàn)高速、高精加工，與之配套的功能部件如電主軸、直線電機得到了快速的發(fā)展，應(yīng)用領(lǐng)域進一步擴大。
1.2 5軸聯(lián)動加工和復(fù)合加工機床快速發(fā)展
采用5軸聯(lián)動對三維曲面零件的加工，可用刀具最佳幾何形狀進行切削，不僅光潔度高，而且效率也大幅度提高。一般認(rèn)為，1臺5軸聯(lián)動機床的效率可以等于2臺3軸聯(lián)動機床，特別是使用立方氮化硼等超硬材料銑刀進行高速銑削淬硬鋼零件時，5軸聯(lián)動加工可比3軸聯(lián)動加工發(fā)揮更高的效益。但過去因5軸聯(lián)動數(shù)控系統(tǒng)、主機結(jié)構(gòu)復(fù)雜等原因，其價格要比3軸聯(lián)動數(shù)控機床高出數(shù)倍，加之編程技術(shù)難度較大，制約了5軸聯(lián)動機床的發(fā)展。
當(dāng)前由于電主軸的出現(xiàn)，使得實現(xiàn)5軸聯(lián)動加工的復(fù)合主軸頭結(jié)構(gòu)大為簡化，其制造難度和成本大幅度降低，數(shù)控系統(tǒng)的價格差距縮小。因此促進了復(fù)合主軸頭類型5軸聯(lián)動機床和復(fù)合加工機床（含5面加工機床）的發(fā)展。
在EMO2001展會上，新日本工機的5面加工機床采用復(fù)合主軸頭，可實現(xiàn)4個垂直平面的加工和任意角度的加工，使得5面加工和5軸加工可在同一臺機床上實現(xiàn)，還可實現(xiàn)傾斜面和倒錐孔的加工。德國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)動加工，可由CNC系統(tǒng)控制或CAD/CAM直接或間接控制。
1.3 智能化、開放式、網(wǎng)絡(luò)化成為當(dāng)代數(shù)控系統(tǒng)發(fā)展的主要趨勢
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，如加工過程的自適應(yīng)控制，工藝參數(shù)自動生成；為提高驅(qū)動性能及使用連接方便的智能化，如前饋控制、電機參數(shù)的自適應(yīng)運算、自動識別負(fù)載自動選定模型、自整定等；簡化編程、簡化操作方面的智能化，如智能化的自動編程、智能化的人機界面等；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。
2對我國數(shù)控技術(shù)及其產(chǎn)業(yè)發(fā)展的基本估計
我國數(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，由于國外的技術(shù)封鎖和我國的基礎(chǔ)條件的限制，數(shù)控技術(shù)的發(fā)展較為緩慢。第二階段是在國家的“六五”、“七五”期間以及“八五”的前期，即引進技術(shù)，消化吸收，初步建立起國產(chǎn)化體系階段。在此階段，由于改革開放和國家的重視，以及研究開發(fā)環(huán)境和國際環(huán)境的改善，我國數(shù)控技術(shù)的研究、開發(fā)以及在產(chǎn)品的國產(chǎn)化方面都取得了長足的進步。第三階段是在國家的“八五”的后期和“九五”期間，即實施產(chǎn)業(yè)化的研究，進入市場競爭階段。在此階段，我國國產(chǎn)數(shù)控裝備的產(chǎn)業(yè)化取得了實質(zhì)性進步。在“九五”末期，國產(chǎn)數(shù)控機床的國內(nèi)市場占有率達(dá)50％，配國產(chǎn)數(shù)控系統(tǒng)（普及型）也達(dá)到了10％。
縱觀我國數(shù)控技術(shù)近50年的發(fā)展歷程，特別是經(jīng)過4個5年計劃的攻關(guān)，總體來看取得了以下成績。
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)。我國現(xiàn)在已基本掌握了從數(shù)控系統(tǒng)、伺服驅(qū)動、數(shù)控主機、專機及其配套件的基礎(chǔ)技術(shù)，其中大部分技術(shù)已具備進行商品化開發(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。蘭州電機廠、華中數(shù)控等一批伺服系統(tǒng)和伺服電機生產(chǎn)廠以及北京第一機床廠、濟南第一機床廠等若干數(shù)控主機生產(chǎn)廠。這些生產(chǎn)廠基本形成了我國的數(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)化方面取得了長足的進步，但我們也要清醒地認(rèn)識到，我國高端數(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)狀與我國的現(xiàn)實需求還有較大的差距。雖然從縱向看我國的發(fā)展速度很快，但橫向比（與國外對比）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)水平差距有擴大趨勢。從國際上來看，對我國數(shù)控技術(shù)水平和產(chǎn)業(yè)化水平估計大致如下。
a.技術(shù)水平上，與國外先進水平大約落后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)量相對差；可靠性不高，商品化程度不足；國產(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，對競爭前數(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；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方面。
a.認(rèn)識方面。對國產(chǎn)數(shù)控產(chǎn)業(yè)進程艱巨性、復(fù)雜性和長期性的特點認(rèn)識不足；對市場的不規(guī)范、國外的封鎖加扼殺、體制等困難估計不足；對我國數(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.機制方面。不良機制造成人才流失，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)劃的有效實施，往往規(guī)劃理想，實施困難。
d.技術(shù)方面。企業(yè)在技術(shù)方面自主創(chuàng)新能力不強，核心技術(shù)的工程化能力不強。機床標(biāo)準(zhǔn)落后，水平較低，數(shù)控系統(tǒng)新標(biāo)準(zhǔn)研究不夠。
3對我國數(shù)控技術(shù)和產(chǎn)業(yè)化發(fā)展的戰(zhàn)略思考
3.1戰(zhàn)略考慮
我國是制造大國，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，即要掌握先進制造核心技術(shù)，否則在新一輪國際產(chǎn)業(yè)結(jié)構(gòu)