機床中英文翻譯資料

1、數(shù)字控制的歷史在機床領域工作的任何人都不能忽視計算機對制造業(yè)的影響。這些機床對工業(yè)的影響能力強迫公司經(jīng)理和所有者更新他們的思想來保持競爭力。這些機床的固有準確性和反復性已經(jīng)幫助了質(zhì)量過程工具例如統(tǒng)計過程控制在金工車間獲得立足處。nc/cnc機床的演變數(shù)字控制其實不是什么新東西。早在1808年織機裝入帶孔的金屬卡片控制所生產(chǎn)布料的樣式。機器的每根針由裝入的卡上孔的有無來控制。卡片成為機器的程序。如果改變了卡片，樣式也跟著改變。自動鋼琴也是數(shù)字控制的例子。自動鋼琴使用帶孔的紙卷。孔的有無決定音符是否被演奏?？諝獗挥糜诟袘资欠翊嬖凇Ｓ嬎銠C的發(fā)明是數(shù)字控制的一個轉折點。1943年，稱作eniac (

2、電子數(shù)字積分器和計算機)的第一臺計算機被制成。eniac計算機非常大。它占地超過1500平方英尺并使用大約18,000根真空管運算。但真空管發(fā)熱成為一個困擾的問題。計算機僅能運行幾分鐘管子就失效。另外，計算機重達數(shù)噸并非常難于編程。eniac通過使用數(shù)以萬計的開關來編程。今天價值15美圓的計算器也遠比這個早期的嘗試更功能強大。計算機技術領域真正的轉折點是1948年晶體管的發(fā)明。晶體管是真空管的替換品。它體積小，便宜，可靠，耗能少，并且發(fā)熱低。真空管的完美取代品。直到20世紀60年代晶體管才在工業(yè)中大量使用。集成電路原件在1959年一種新技術涌現(xiàn)了：集成電路（ics）。集成電路實際是芯片上的控制

3、電路。當制造商發(fā)現(xiàn)了如何小型化電路，它比晶體管更有助于減小尺寸和改進電子控制的可靠性。大規(guī)模集成電路大規(guī)模生產(chǎn)是在1965年。在1974年發(fā)明了微處理器。由此產(chǎn)生了微型計算機，使小規(guī)模運用成為可能。計算機記憶卡制造的巨大進步使它計算機更加功能強大而容易支付。作為政府生產(chǎn)高精度副翼的方法數(shù)控機床的原始構想源于20世紀50年代。這些復雜的零件用傳統(tǒng)方法制造并且通過和模板作比較來檢驗它們。模板也必須用傳統(tǒng)方法制造，是非常費時和不精確的。然而，在michigan一個商店，一個叫做john parsons的人正在研究一種新方法來改進直升機動葉片模板的制造方法。parsons是工具室學徒而且沒有大學學位。

4、parson的方法是計算沿副翼表面的坐標點。通過計算大量的中間點然后移動機床到每個點，模板的精度就改進了。parsons提出用穿孔的卡片來進行大量計算的主意。這些數(shù)據(jù)用來定位機床。1948年parsons向空軍遞交發(fā)展生產(chǎn)這些模板的機器的提案并得到認同。他第一次試圖在自動控制中使用穿孔卡制表機計算沿副翼曲線的方位并用普通銑床定位刀具到制表機位置。他有二名操作員，一個移動機器的每根軸。這種方法生產(chǎn)的副翼比先前方法高達十倍精度，但仍然是一個非常費時的過程。1949年，空軍要求parsons生產(chǎn)能移動機器的軸來自動計算點位置的一種控制系統(tǒng)。麻省理工學院(mit)由parsons轉包來發(fā)展能控制機器軸

5、的馬達。伺服電動機誕生了。parsons構想了隨后的系統(tǒng)。計算機能計算刀具應該遵循的軌跡并在穿孔卡上儲存信息。機器的操作者能讀出卡片。控制機器從操作者得到數(shù)據(jù)并控制附著在每根軸上的馬達。1951年 mit被授予開發(fā)控制機器的主要合同。第一臺由parsons和mit生產(chǎn)的機器在1952年展出。叫做cincinnati hydrotel，它是一臺三軸垂直心軸的銑床。這個控制機器使用真空管。在使人編程更容易的其中一個早期嘗試叫做apt（自動編程工具）符號語言。apt，發(fā)明于1954年，使用機床能讀懂的和英文相似的符號語言來編制程序。記住，機器需要零件的幾何外型和例如速度、飼料和冷卻液的機器指令來運行

6、。apt使人們寫這些程序變得更容易，這些程序隨后又被翻譯成機器能讀懂的另一種程序。1955年空軍得到制造數(shù)控機器的35，000，000美圓的合同。第一臺數(shù)控機床非常龐大。這個控制機器靠真空管運行并需要一個分開的計算機來生成它的二進制磁帶代碼。（二進制代碼系統(tǒng)使用0和1）。復雜零件的編程需要非常專業(yè)的人員。隨著繼續(xù)的發(fā)展和提煉，60年代初期數(shù)字控制機器在工業(yè)中變得更加普通。數(shù)字控制機器廣泛接受，它們變得更加功能強大和容易使用。直到大約1976年這些機器被稱作nc（數(shù)字控制）機器。1976年cnc (計算機數(shù)字控制)機器出現(xiàn)了。這些控制機器使用微處理器給了他們額外的功能。他們也以外存儲為特色。代表

7、性的ncs每次讀取一步程序（塊）并執(zhí)行它；然而，cnc機床能夠存儲整個程序。20世紀70和80年代后期計算機技術的改善使數(shù)控機床的價格跌到一個很多制造公司不能再沒有它們的水平。history of numerical controlanyone working in the machine tool field cannot ignore the influence of the computer in manufacturing. the capabilities that these machine tools have given to the industry have forced

8、managers and owners of companies to update their thinking to stay competitive. the inherent accuracy and repeatability of these machine tools have helped quality process tools such as statistical process control gain a foothold in machine shops.evolution of the nc/cnc machinenumerical control is not

9、hing new. as early as 1808 weaving machines used metal cards with holes punched in them to control the pattern of the cloth being produced. each needle on the machine was controlled by the presence or absence of a hole on the punched cards. the cards were the program for the machine. if the cards we

10、re changed, the pattern changed.the players piano is also an example of numerical control. the player piano uses a roll of paper with holes punched in it. the presence or absence of a hole determined if that note was played. air was used to sense whether a hole was present.the invention of the compu

11、ter was one of the turning points in numerical control. in 1943 the first computer, called eniac (electronic numerical integrator and computer) was built.the eniac computer was very large. it occupied more than 1500 square feet and used approximately 18,000 vacuum tubes to do its calculations. the h

12、eat generated by the vacuum tubes was a constant problem. the computer could operate only a few minutes without a tube failing. in addition, the computer weighed many tons and was very difficult to program. eniac was programmed through the use of thousands of switches. the $15 calculator available t

13、oday is much more powerful than this early attempt.the real turning point in computer technology was the invention of the transistor in 1948. the transistor was the replacement for the vacuum tube. it was very small, cheap, dependable, used very little power, and generated very little heat: the perf

14、ect replacement for the vacuum tube. the transistor did not see much industrial use until the 1960s.integrated circuitryin 1959 a new technology emerged: integrated circuits (ics). integrated circuits were actually control circuits on a chip. when manufacturers discovered how to miniaturize circuits

15、, it helped reduce the size and improve the dependability of electronic control even more than the transistor had. large-scale integrated circuits first were produced in 1965.in 1974 the microprocessor was invented. this made the microcomputer, and thus small application, possible. great strides in

16、the manufacture of memory for computers helped make computers more powerful and affordable.the original conception of numerically controlled machine tools occurred in the 1950s as a method of producing airfoils of great accuracy for the government.these complex parts were made by manual machining me

17、thods and inspected by comparing them to templates. the templates also had to be manufactured by manual methods, which was very time consuming and inaccurate.however, in a shop in traverse city, michigan, a man named john parsons was working on a method to improve the production of inspection templa

18、tes for helicopter rotor blades. parsons started as a tool room apprentice and had no college degree. parsons method involved calculating the coordinate points along the airfoil surface. by calculating a large number of intermediate points and then manually moving the machine tool to each of these p

19、oints, the accuracy of the templates was improved. parsons came up with the idea of using punched cards for the many calculations. the data could then be used to position the machine tool. parsons submitted a proposal to the air force to develop a machine to produce these templates and received a de

20、velopment contract in 1948. his first attempts at automatic position control used punchcard tabulating machines to calculate the positions along the airfoil curve and an ordinary manual milling machine to position the tool to the tabulated positions. he had two operators, one to move each axis of th

21、e machine. this method produced airfoils tens of times more accurate than the preceding method, but was still a very time-consuming process.in 1949,the air force awarded parsons a contract to produce a control system that could move the axis of a machine to calculated points automatically. the massa

22、chusetts institute of technology (mit) was subcontracted by parsons to develop a motor that could control the axis of the machines. the servo motor was born.parsons envisioned the following system. a computer would calculate the path that the tool should follow and store that information on punched

23、cards. a reader at the machine would then read the cards. the machine control would take the data from the reader and control the motors attached to each axis.in 1951 mit was awarded the prime contract to develop the machine control. the first machine produced by parsons and mit was demonstrated in

24、1952. called a cincinnati hydrotel, it was a three-axis vertical spindle milling machine. the machine control used vacuum tubes.one of the first attempts at making programming easier for people was called apt (automatically programmed tool) symbolic language. apt, invented in 1954, used english-like

25、 symbolic language to produce a program that the machine tool could understand. remember, a machine needs the geometry of the part and machining instructions such as speeds, feeds, and coolant to operate. apt made it easier for people to write these programs, which were then translated to a program

26、that the machine could understand.in 1955 the air force awarded $35million in contracts to manufacture numerical control machines. the first numerically controlled machine tools were very bulky. the machine control was vacuum-tube operated and needed a separate computer to generate its binary tape codes. (binary coding systems use 1s and 0s).