數(shù)控專(zhuān)業(yè)英語(yǔ)

1、Unit 1 Introduction to Computer Introduction to Computer Numerical Control ManufacturingNumerical Control Manufacturing第第1 1單元單元 計(jì)算機(jī)數(shù)控加工簡(jiǎn)介計(jì)算機(jī)數(shù)控加工簡(jiǎn)介Reading TargetReading TargetAfter reading this unit, you should be able to explain what computer numerical control (CNC) is and what basic components com

2、prise CNC systems.TextText 1.1Definition of Computer Numerical Control and its components A computer numerical control (CNC) machine is an NC machine with the added feature of an on-board computer. The on-board computer is often referred to as the machine control unit or MCU. 1.1 CNC的定義及其系統(tǒng)組成的定義及其系統(tǒng)

3、組成 計(jì)算機(jī)數(shù)控機(jī)床就是在計(jì)算機(jī)數(shù)控機(jī)床就是在NC機(jī)床的基礎(chǔ)上附加一個(gè)內(nèi)機(jī)床的基礎(chǔ)上附加一個(gè)內(nèi)置式計(jì)算機(jī)，這種內(nèi)置式計(jì)算機(jī)通常被稱為機(jī)床控制單元置式計(jì)算機(jī)，這種內(nèi)置式計(jì)算機(jī)通常被稱為機(jī)床控制單元或或MCU。NC機(jī)床的控制單元通常由硬件構(gòu)成，也就是說(shuō)機(jī)床的控制單元通常由硬件構(gòu)成，也就是說(shuō)機(jī)床的功能是由控制器內(nèi)置的物理電子元件控制的。機(jī)床的功能是由控制器內(nèi)置的物理電子元件控制的。 TextTextControl units for NC machines are usually hard wired. This means that a machine functions are controll

4、ed by the physical electronic elements that are built into the controller. Simply put, numerical control is a method of automatically operating a manufacturing machine based on a code of letters, numbers, and special characters. NC機(jī)床的控制單元通常由硬件構(gòu)成，也就是說(shuō)機(jī)床的功機(jī)床的控制單元通常由硬件構(gòu)成，也就是說(shuō)機(jī)床的功能是由控制器內(nèi)置的物理電子元件控制的。簡(jiǎn)單地說(shuō)

5、，能是由控制器內(nèi)置的物理電子元件控制的。簡(jiǎn)單地說(shuō)，數(shù)字控制是基于代碼自動(dòng)操作制造類(lèi)機(jī)床的一種方法，數(shù)字控制是基于代碼自動(dòng)操作制造類(lèi)機(jī)床的一種方法，這些代碼由字母、數(shù)字和特殊字符組成。這些代碼由字母、數(shù)字和特殊字符組成。 A complete set of coded instructions for executing an operation is called a program. Such programs are stored in RAM or the random-access memory portion of the computer. They can be played b

6、ack, edited, and processed by the control. Thus, the machine functions are encoded into the computer at the time of manufacture. 所謂的程序就是用于執(zhí)行某一操作的一整套代碼表示的所謂的程序就是用于執(zhí)行某一操作的一整套代碼表示的指令，而這些程序是存放在計(jì)算機(jī)的隨機(jī)存儲(chǔ)器中的，控指令，而這些程序是存放在計(jì)算機(jī)的隨機(jī)存儲(chǔ)器中的，控制器可以對(duì)它們進(jìn)行重新調(diào)用，編寫(xiě)以及處理等操作。因制器可以對(duì)它們進(jìn)行重新調(diào)用，編寫(xiě)以及處理等操作。因此，我們可以通過(guò)對(duì)計(jì)算機(jī)進(jìn)行編碼從而在加工時(shí)實(shí)

7、現(xiàn)機(jī)此，我們可以通過(guò)對(duì)計(jì)算機(jī)進(jìn)行編碼從而在加工時(shí)實(shí)現(xiàn)機(jī)床操作的各種功能。床操作的各種功能。TextText The components found in many CNC systems are shown in Figure 1-1 . Machine control unit: generates, stores and processes CNC programs. The machine control unit also contains the machine motion controller in the form of an executive software progr

8、am. NC machine: responds to programmed signals from the machine control unit and manufactures the part. CNC系統(tǒng)中常見(jiàn)的組成部分如圖系統(tǒng)中常見(jiàn)的組成部分如圖1-1所示。所示。 機(jī)床控制單元：生成、存儲(chǔ)和處理機(jī)床控制單元：生成、存儲(chǔ)和處理CNC程序。機(jī)床程序。機(jī)床控制單元還包括機(jī)床運(yùn)動(dòng)控制器，該控制器是一個(gè)可執(zhí)控制單元還包括機(jī)床運(yùn)動(dòng)控制器，該控制器是一個(gè)可執(zhí)行的軟件程序。行的軟件程序。NC機(jī)床：響應(yīng)來(lái)自機(jī)床控制單元的程序機(jī)床：響應(yīng)來(lái)自機(jī)床控制單元的程序信號(hào)并對(duì)零件進(jìn)行加工。信號(hào)并對(duì)零件進(jìn)行加

9、工。 TextTextTextTextFig 1-1 Components of modern CNC system 現(xiàn)代現(xiàn)代CNC系統(tǒng)的組成系統(tǒng)的組成1.2Types of CNC equipment Machining centers are the latest development in CNC technology. These systems come equipped with automatic tool changers with the capability of changing up to 90 or more tools. Many are also fitted

10、with the movable rectangular worktables called pallets. The pallets are used to automatically load and unload work pieces. 1.2 CNC設(shè)備的類(lèi)型設(shè)備的類(lèi)型 加工中心在加工中心在CNC技術(shù)中屬于最前沿的。它們裝有自技術(shù)中屬于最前沿的。它們裝有自動(dòng)換刀裝置，可換刀具數(shù)高達(dá)動(dòng)換刀裝置，可換刀具數(shù)高達(dá)90把甚至更多。許多加工把甚至更多。許多加工中心還裝有可移動(dòng)的長(zhǎng)方形工作臺(tái)，即托盤(pán)系統(tǒng)。這種中心還裝有可移動(dòng)的長(zhǎng)方形工作臺(tái)，即托盤(pán)系統(tǒng)。這種托盤(pán)系統(tǒng)用來(lái)自動(dòng)裝卸工件。托盤(pán)系統(tǒng)用來(lái)自

11、動(dòng)裝卸工件。TextText At a single setup machining centers can perform such operations as milling, drilling, tapping, boring, and so on. Additionally by utilizing indexing heads, some centers are capable of executing these tasks on many different faces of a part and at specified angles. Machining centers sa

12、ve production time and cost by reducing the need for moving a part from one machine to another. 加工中心只需一次裝卡就可以完成銑、鉆、攻絲、鏜加工中心只需一次裝卡就可以完成銑、鉆、攻絲、鏜等多種加工操作。此外，一些加工中心利用分度頭可等多種加工操作。此外，一些加工中心利用分度頭可以對(duì)零件不同的面和特定的角度進(jìn)行加工。通過(guò)減少以對(duì)零件不同的面和特定的角度進(jìn)行加工。通過(guò)減少零件在機(jī)床間轉(zhuǎn)移，加工中心能夠節(jié)省生產(chǎn)時(shí)間與成零件在機(jī)床間轉(zhuǎn)移，加工中心能夠節(jié)省生產(chǎn)時(shí)間與成本。本。TextTextTextText

13、 Turning centers with increased capacity tool changers are also making strong appearance in modern production shops. These CNC machines are capable of executing many different types of lathe cutting operations simultaneously on rotating part. 具有大容量刀庫(kù)的車(chē)削中心在現(xiàn)代制造廠中占據(jù)具有大容量刀庫(kù)的車(chē)削中心在現(xiàn)代制造廠中占據(jù)著顯著位置。這些著顯著位置。這

14、些CNC機(jī)床能對(duì)旋轉(zhuǎn)的工件同時(shí)進(jìn)機(jī)床能對(duì)旋轉(zhuǎn)的工件同時(shí)進(jìn)行多種車(chē)削加工。行多種車(chē)削加工。TextText In addition to machining centers and turning centers, CNC technology has also been applied to many other types of manufacturing equipment. Among these are wire electrical discharge machines (wire EDM) and laser cutting machines. 除加工中心和車(chē)削中心之外，除加工中心

15、和車(chē)削中心之外，CNC技術(shù)還被廣技術(shù)還被廣泛用于其他許多類(lèi)型的設(shè)備，其中包括線切割機(jī)床泛用于其他許多類(lèi)型的設(shè)備，其中包括線切割機(jī)床和激光切割機(jī)。和激光切割機(jī)。TextText Wire EDM machines utilize a very thin wire as an electrode. The wire is stretched between two rollers and cuts the part like a band-saw. Material is removed by the erosion caused by a spark that moves horizontall

16、y with the wire. CNC is used to control horizontal table movements. 線切割機(jī)是用一根很細(xì)的切割絲做電極。切割線切割機(jī)是用一根很細(xì)的切割絲做電極。切割絲在兩個(gè)導(dǎo)輪之間拉緊，像帶鋸一樣切割工件。切絲在兩個(gè)導(dǎo)輪之間拉緊，像帶鋸一樣切割工件。切割絲水平移動(dòng)所產(chǎn)生的電火花會(huì)將材料腐蝕掉，而割絲水平移動(dòng)所產(chǎn)生的電火花會(huì)將材料腐蝕掉，而CNC就是用來(lái)控制水平工作臺(tái)的移動(dòng)。就是用來(lái)控制水平工作臺(tái)的移動(dòng)。 TextText Laser cutting CNC machines utilize an intense beam of focused

17、 laser light to cut the part. Material under the laser beam undergoes a rapid rise in temperature and is vaporized. If the beam power is high enough, it will penetrate through the material. Because no mechanical cutting forces are involved, lasers cut parts with a minimum of distortion, they have be

18、en very effective in machining slots and drilling holes. 激光切割激光切割CNC機(jī)床能利用一束強(qiáng)烈的聚焦光線來(lái)切機(jī)床能利用一束強(qiáng)烈的聚焦光線來(lái)切割工件。材料在光線的照射下溫度會(huì)驟然上升并汽化。若割工件。材料在光線的照射下溫度會(huì)驟然上升并汽化。若光束能量足夠高就會(huì)將材料穿透。由于沒(méi)有機(jī)械切削力，光束能量足夠高就會(huì)將材料穿透。由于沒(méi)有機(jī)械切削力，所以激光加工的工件變形非常小，激光切割機(jī)對(duì)加工窄槽所以激光加工的工件變形非常小，激光切割機(jī)對(duì)加工窄槽和鉆孔非常有效和鉆孔非常有效 。Key TermsComputer Numerical Control 計(jì)算機(jī)數(shù)字控制計(jì)算機(jī)數(shù)字控制MCU Machine control unit 機(jī)床控制單元機(jī)床控制單元electronic element 電子元件電子元件controller 控制器控制器RAM random-access memory 隨機(jī)存儲(chǔ)器隨機(jī)存儲(chǔ)器machining center 加工中心加工中心pallet 托盤(pán)托盤(pán)ATC automatic tool changer 自動(dòng)換刀裝置自動(dòng)換刀裝置work piecework