数控专业英语36327.pptx

Unit 1 Introduction to Computer Introduction to Computer Numerical Control ManufacturingNumerical Control Manufacturing第第1 1单元单元 计算机数控加工简介计算机数控加工简介Reading TargetReading TargetAfter reading this unit,you should be able to explain what computer numerical control(CNC)is and what basic components comprise 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的定义及其系统组成的定义及其系统组成 计算机数控机床就是在计算机数控机床就是在NC机床的基础上附加一个内机床的基础上附加一个内置式计算机，这种内置式计算机通常被称为机床控制单元置式计算机，这种内置式计算机通常被称为机床控制单元或或MCU。NC机床的控制单元通常由硬件构成，也就是说机床的控制单元通常由硬件构成，也就是说机床的功能是由控制器内置的物理电子元件控制的。机床的功能是由控制器内置的物理电子元件控制的。TextTextControl units for NC machines are usually hard wired.This means that a machine functions are controlled 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机床的控制单元通常由硬件构成，也就是说机床的功机床的控制单元通常由硬件构成，也就是说机床的功能是由控制器内置的物理电子元件控制的。简单地说，能是由控制器内置的物理电子元件控制的。简单地说，数字控制是基于代码自动操作制造类机床的一种方法，数字控制是基于代码自动操作制造类机床的一种方法，这些代码由字母、数字和特殊字符组成。这些代码由字母、数字和特殊字符组成。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 back,edited,and processed by the control.Thus,the machine functions are encoded into the computer at the time of manufacture.所谓的程序就是用于执行某一操作的一整套代码表示的所谓的程序就是用于执行某一操作的一整套代码表示的指令，而这些程序是存放在计算机的随机存储器中的，控制指令，而这些程序是存放在计算机的随机存储器中的，控制器可以对它们进行重新调用，编写以及处理等操作。因此，器可以对它们进行重新调用，编写以及处理等操作。因此，我们可以通过对计算机进行编码从而在加工时实现机床操作我们可以通过对计算机进行编码从而在加工时实现机床操作的各种功能。的各种功能。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 program.NC machine:responds to programmed signals from the machine control unit and manufactures the part.CNC系统中常见的组成部分如图系统中常见的组成部分如图1-1所示。所示。机床控制单元：生成、存储和处理机床控制单元：生成、存储和处理CNC程序。机床程序。机床控制单元还包括机床运动控制器，该控制器是一个可执控制单元还包括机床运动控制器，该控制器是一个可执行的软件程序。行的软件程序。NC机床：响应来自机床控制单元的程序机床：响应来自机床控制单元的程序信号并对零件进行加工。信号并对零件进行加工。TextTextTextTextFig 1-1 Components of modern CNC system 现代现代CNC系统的组成系统的组成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 with the movable rectangular worktables called pallets.The pallets are used to automatically load and unload work pieces.1.2 CNC设备的类型设备的类型 加工中心在加工中心在CNC技术中属于最前沿的。它们装有自技术中属于最前沿的。它们装有自动换刀装置，可换刀具数高达动换刀装置，可换刀具数高达90把甚至更多。许多加工把甚至更多。许多加工中心还装有可移动的长方形工作台，即托盘系统。这种中心还装有可移动的长方形工作台，即托盘系统。这种托盘系统用来自动装卸工件。托盘系统用来自动装卸工件。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 save production time and cost by reducing the need for moving a part from one machine to another.加工中心只需一次装卡就可以完成铣、钻、攻丝、镗加工中心只需一次装卡就可以完成铣、钻、攻丝、镗等多种加工操作。此外，一些加工中心利用分度头可等多种加工操作。此外，一些加工中心利用分度头可以对零件不同的面和特定的角度进行加工。通过减少以对零件不同的面和特定的角度进行加工。通过减少零件在机床间转移，加工中心能够节省生产时间与成零件在机床间转移，加工中心能够节省生产时间与成本。本。TextTextTextText 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.具有大容量刀库的车削中心在现代制造厂中占据具有大容量刀库的车削中心在现代制造厂中占据着显著位置。这些着显著位置。这些CNC机床能对旋转的工件同时进机床能对旋转的工件同时进行多种车削加工。行多种车削加工。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.除加工中心和车削中心之外，除加工中心和车削中心之外，CNC技术还被广技术还被广泛用于其他许多类型的设备，其中包括线切割机床泛用于其他许多类型的设备，其中包括线切割机床和激光切割机。和激光切割机。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 horizontally with the wire.CNC is used to control horizontal table movements.线切割机是用一根很细的切割丝做电极。切割线切割机是用一根很细的切割丝做电极。切割丝在两个导轮之间拉紧，像带锯一样切割工件。切丝在两个导轮之间拉紧，像带锯一样切割工件。切割丝水平移动所产生的电火花会将材料腐蚀掉，而割丝水平移动所产生的电火花会将材料腐蚀掉，而CNC就是用来控制水平工作台的移动。就是用来控制水平工作台的移动。TextText Laser cutting CNC machines utilize an intense beam of focused 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 been very effective in machining slots and drilling holes.激光切割激光切割CNC机床能利用一束强烈的聚焦光线来切机床能利用一束强烈的聚焦光线来切割工件。材料在光线的照射下温度会骤然上升并汽化。若割工件。材料在光线的照射下温度会骤然上升并汽化。若光束能量足够高就会将材料穿透。由于没有机械切削力，光束能量足够高就会将材料穿透。由于没有机械切削力，所以激光加工的工件变形非常小，激光切割机对加工窄槽所以激光加工的工件变形非常小，激光切割机对加工窄槽和钻孔非常有效和钻孔非常有效。Key TermsComputer Numerical Control 计算机数字控制计算机数字控制MCU Machine control unit 机床控制单元机床控制单元electronic element 电子元件电子元件controller 控制器控制器RAM random-access memory 随机存储器随机存储器machining center 加工中心加工中心pallet 托盘托盘ATC automatic tool changer 自动换刀装置自动换刀装置work pieceworkpiece 工件工件Key Termsmilling 铣削铣削drilling 钻孔钻孔tapping 攻丝攻丝boring 镗孔镗孔indexing head 分度头分度头turning center 车削中心车削中心lathe 车床车床electrical discharge machine 电火花加工机床电火花加工机床wire EDM wire electrical discharge machine 线切割电线切割电火花加工机床火花加工机床Key Termslaser cutting machine 激光切割机床激光切割机床machining机械加工机械加工slot 窄槽窄槽谢谢观看/欢迎下载BY FAITH I MEAN A VISION OF GOOD ONE CHERISHES AND THE ENTHUSIASM THAT PUSHES ONE TO SEEK ITS FULFILLMENT REGARDLESS OF 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