Unit 6 The Components of CNC Machine
? Section I Dialogue
It is said that CNC machine is very popular nowadays, but I’m still strange to it. Could you please tell me something about it?
据说数控机床是现在非常流行,但是我对机床还是不了解。你能告诉我一些关于它的事吗? A CNC machine is an NC machine with additional features of an on-board computer. 计算机数控机床是具有安装在机床上的计算机的附加功能的数控机床。 Oh, I see. But what is an on-board computer? 哦，我明白了。但是什么是安装在机床上的电脑?
The on-board computer refers to the machine control unit (MCU). 安装在机床上的电脑指的是指机床控制单元(MCU)。 You mean the control unit of NC machine. 你的意思是数控机床的控制单元。
Not exactly. There are some differences between them. The control unit of NC machine is usually hard wired. However, the on-board computer is soft wired. 件连接。
With the computer, there must be some programs. 同时计算机上必须有一些程序。
You’re really smart. With CNC program entered, the computer can operate the machine automatically. 你真聪明。随着数控程序的输入，计算机就可以自动操作机床。
不完全是这样，它们之间有一些区别。数控机床控制单元通常是硬件连接，而安装在机床上的电脑是软
? Section II Reading
The Components of CNC Machine 数控机床的组成
CNC machine tools are complex assemblies. However, in general, any CNC machine tool consists of the following units: computer, control system, drive motor and tool changer.
数控机床是复杂的装配。然而，在一般来情况下，任何数控机床包含以下单元：计算机、控制系统、驱动电机和换刀装置。
Computer controls data. If there is a minicomputer programming, say, a radius, the computer will calculate all the points on the tool path.
计算机控制数据。如果有一个微型计算机编程，比如说（知道）一个半径，计算机将计算刀具路径上所有点的坐标值。
The CNC control system activates the appropriate machine functions, causes axis motion, and in general, follows the instructions given in the program. The drives motor controls the machine slide movement on CNC equipment.
数控系统激活相应的机床功能，使轴运动，并在一般情况下，执行程序的指示。驱动电机控制数控机床上设备的滑动。
Tool changer is set on most machines and allows multiple tools to be quickly changed. 大多数机床装有换刀系统设置，并且允许多个工具迅速改变。
For a universal style, CNC lathe, for example, is composed of bed, headstock and spindle, chuck, turret construction, tailstock and computer system.
数控车床一般的类型，举例来说，是由床身、主轴箱、主轴、卡盘、转塔刀架、尾座和计算机系统组成。
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? Section III Words and Expressions
additional [?'di??n?l] adj. 附加的，额外的 add – addit – addition
on-board ['?n'b?:d, '?:n-] adj. 在船上的；在车上的；在飞机上的；装在数控机床上的 broad [br?:d] n. 宽阔部分 adj. 宽的，辽阔的；显著的；大概的 adv. 宽阔地 abroad [?'br?:d] n. 海外；异国adj. 往国外的adv. 在国外；到海外 a- [?] pref. 处于...状态或过程中；在?之上；朝着；用于加强语气 activate ['?ktiveit]vt. 刺激；使活动vi. 激活；有活力 appropriate [?'pr?uprieit] adj. 适当的 vt. 占用；拨出
universal [,ju:ni'v?:s?l] adj. 普遍的；通用的；宇宙的；全世界的n. 一般概念；普通性 Universal:环球 | 环球公司 | 环球唱片 headstock ['hedst?k] n. 主轴承 主轴箱
chuck [t??k] vt. 丢弃，抛掷；驱逐；轻拍 n. [机] 卡盘；抚弄；赶走；咯咯声 turret ['t?rit, 't?:-, 'tu?-] n. 炮塔；角楼；小塔；攻城用仰冲车 转塔刀架 tailstock ['teilst?k] n. （车床的可调整或可滑动的）[机] 尾座
? Section IV Technical Terms
on-board
machine control unit hard wire soft wire drive motor tool changer tool path
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Unit 7 CNC Programming
? Section I Dialogue
It is believed that conversational programming and CAM system programming are very popular in recent years.
据说对话式编程和CAM系统编程近年非常流行。
Yes, but nowadays CAM system programming us more popular because CAM systems can program different kinds of machines with the same basic language while conversational controls can only generate part programs for a single machine.
是的，但现在CAM系统编程更受欢迎，因为CAM系统能够用相同的基本语言编写多种机床程序，而对话式只能产生为一台机床编写部分程序。
Why not use manual programming at present? 现在为什么不使用手工编程呢?
Using a computer to prepare part programs can improve efficiency and accuracy. 用电脑做编写部分程序就可以提高效率和准确性。
In your opinion, it isn’t necessary for us to know manual programming. 在你看来, 我们一定必须掌握手工编程。
Not exactly. Successful use of computerized programming requires understanding of manual programming method.
不完全是这样。成功地使用计算机编程需要了解手工编程的方法。
That is to say, knowing manual programming well - really understanding it - will be the key to master the power of CAM software.
也就是说，掌握手工编程，真正了解它，是精通CAM软件的关键。 Completely right. You’re really a quick learner. 完全正确，你真聪明。
? Section II Reading
Methods for CNC Programming 数控编程方法
There are three methods of developing CNC programs: manual programming, conversational programming, and CAM system programming.
有三种方法开发（编写）CNC程序:手工编程、对话式编程和CAM编程。 Manual Programming 手工编程
Manual programming tends to be somewhat boring. Admittedly, the words and commands involved with manual programming can be somewhat cryptic. However, all CNC programmers should have a good understanding of manual programming techniques regardless of whether or not they are used.手工编程往往是有点枯燥。无可否认的（诚然），使用手工编程的单词和指令可能有些含糊。但是,所有的数控程序员应该有熟练的掌握手工编程技术，无论他们是否使用。 Conversational Programming 对话编程
This form of programming has become quite popular in recent years. With conversational programming, the program is created at the CNC machine. The programmer will be able to visually check whether various inputs are correct or not as the program is created. When finished, most conversational controls will even show the programmer a tool path plot of what will happen during the machining cycle.
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这种形式的编程近年来已经非常流行。对话编程的程序在数控机床上创建。程序员可以直观的检查各种输入程序正确与否。完成后，对话控制甚至能够给程序员演示在加工循环时的刀具路径图。 CAM System Programming CAM系统编程
CAM systems allow CNC programming to be accomplished at a much higher level than manual programming and are becoming very popular. Generally speaking, a CAM system helps the programmer in three major areas. It keeps the programmer from having to do math calculations, makes it easy to program different kinds of machines with the same basic language, and helps with basic machining practice functions.
CAM系统数控编程比手工编程的完成水平更高，正变的非常受欢迎。一般来说，CAM系统能在三个主要方面帮助程序员。它使程序员不必做数学计算，容易使用相同的基本语言编写不同种类的机床程序，并帮助基本加工实践功能。
? Section III Words and Expressions
conversational [,k?nv?'sei??n?l] adj. 对话的；健谈的 conver – conversation - conversational efficiency [i'fi??nsi] n. 效率；效能；功效 accuracy ['?kjur?si] n. [数] 精确度，准确性 accurate ['?kjur?t] adj. 精确的
manual ['m?nju?l] adj. 手工的；体力的 n. 手册，指南 operation manual 操作手册
computerized [k?m'pju:t?raizd] adj. 电脑的；电脑化的；用电脑处理的
master ['mɑ:st?, 'm?st?] vt. 控制；精通；征服 n. 硕士；主人；大师；教师adj. 主人的；主要的； admittedly [?d'mitidli] adv. 公认地；无可否认地；明白地
involved [in'v?lvd] v. 涉及；使参与；包含（involve的过去式和过去分词） involve [in'v?lv] vt. 包含；牵涉；使陷于；潜心于 cryptic ['kriptik] adj. 神秘的，含义模糊的
somewhat ['s?mhw?t, -hw?t] adv. 有点；多少；几分；稍微 n. 几分；某物 plot [pl?t] n. 情节；图；阴谋vi. 密谋；策划；绘制 vt. 密谋；绘图；划分；标绘 accomplish [?'k?mpli?, ?'k?m-] vt. 完成；实现；达到
? Section IV Technical Terms
Conversational programming CAM system programming Manual programming Tool path plot
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Unit 8 Servo System
? Section I Dialogue
Do you have any idea about servo systems? the closed-loop systems.
是的,我知道一些。 最常用的伺服控制系统是开环和闭环系统。 Oh, I see. Well, what’s the difference between them? uses servo motors to execute machine movements.
开环系统采用步进电机执行机床运动，而闭环系统采用伺服电机执行机床运动。 Could you tell me more about open loop systems?
Yes, of course. Open loop systems have recently gained renewed interest for CNC applications. 好的,可以。近来，开环系统在CNC的应用中重新引起了大家的兴趣。 Thank you very much for your help. My pleasure.
An open loop system utilizes stepping motors to create machine movements while a closed loop system
Yes, I have some idea about it. The most common servo control systems in use are the open loop and
? Section II Reading
Servo System 伺服系统
There are two main systems in use today for controlling CNC machine movements: the open loop servo system and the closed loop servo system.
如今数控机床使用的运动控制的主要系统有两种：开环伺服系统和闭环伺服系统。 no information is fed back to monitor the slide positioning. the accuracy is limited.
在开环伺服系统中，当伺服系统驱动机床滑动时，不会产生反馈信息的监控滑动定位。步进电动机通常在开环系统中作为伺服电机。开环伺服系统通常用于精度要求不高的系统中。
In addition to the elements of an open loop servo system if a measuring device is also introduced to the system to measure the instantaneous position of the tool from an origin, the system is called a closed loop servo system. Closed loop systems are widely used in NC system due to the increased reliability and accuracy.
除了开环伺服系统的要素以外，如果测量设备还采用了从原点来测量机床的瞬时位置，系统就被称为闭环伺服系统。由于提高了可靠性和准确性，闭环系统被广泛应用于数控系统。
In open loop servo systems, once the motion is translated from servo drives to the machine tool slides,
Stepping motors are usually used as
servo drives in open loop servo system. Open loop servo systems are generally used for systems where
? Section III Words and Expressions
utilize ['ju:tilaiz] vt. 利用、运用、应用
renew [ri'nju:] vt. 使更新；续借；复兴；重申 vi. 更新；重新开始 element ['elim?nt] n. 元素；要素；原理；成分；自然环境 instantaneous [,inst?n'teinj?s] adj. 瞬间的；即时的；猝发的 instantaneous:瞬时的 | 瞬间的 | 同时发生的 origin ['?rid?in, '?:-] n. 起源；原点；出身；开端
Oriental [,?:ri'ent?l; ,?u-] n. 东方人 adj. 东方人的；东方的 New Oriental
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