Unit 5 Modern Manufacturing Technology Passage one Introduction to CAD/CAM

Teaching targets

Step A: Lead in Step B: Passage Understanding Step C: Sentences Structure Step D: Assignment

Inventions during the history of industrial society

Which is the most influential one? Digital computer

GLOSSARY OF TERMS material-handling 材料处理 technology-based 基于技术 hand-copying 手工绘图 floppy diskette 软盘 database 数据库 graphics 图形终端 GRT 阴极射线管 random-scan 随机扫描 raster-scan 光栅扫描 liquid-crystal 液晶 CNC 计算机数控 EDM 电火花机床 computer-aided design(CAD) 计算机辅助设计 computer-aided manufacturing(CAM) 计算机辅助制造 Passage understanding

Main parts of the passage The definition of CAD/CAM Rationale for CAD/CAM CAD/CAM hardware CAD/CAM software Applications of CAD/CAM

CAD is defined as the application of computers and graphics software to aid or entrance the product design from conceptualization to documentation CAD 就是应用计算机和图形软件， 在构思到文档形成的过程中来帮 助或改善产品设计

CAM is defined as the effective use of computer technology in manufacturing planning and control CAM 就是在制造计划和控制中 有效的使用计算机技术

Rationale for CAD/CAM The rationale for CAD/CAM is similar to that used to justify any technology- based improvement in manufacturing CAD/CAM 的基本原理类似用于在制 造业中判断任何基于技术改进的原 理

The hardware part of a CAD/CAM consists of the following components:(1)One or more design workstations (2)Digital computer (3)Plotters, printers and other output devices (4)Strong devices CAD/CAM 系统的硬件部分由以下几块组成： 1. 一个 或多个设计工作站； 2. 数字计算机； 3. 绘图仪打印机 和其他输出设备； 4. 存储设备。

Two broad categories of CAD/CAM software are :2-D and 3-D.eg,unigraphics, Pro/Engineer, UG-II, Cimatron CAD/CAM 软件分为两大类：二维 和三维

Some typical applications of CAD/CAM: Programming for NC,CNC, and industrial robot; Design of dies and molds for casting, Design of tools and fixtures and EDM; Quality control and inspection; Process planning and scheduling CAD/CAM 的典型应用如下： 为数控，计算机数控和工业机器人编程 在设计铸造的模具和模型时，可按照预编程序缩 小加工余量 工具，固定装置和 EDM 电极的设计 质量控制和检测 工艺规划与进度安排

Perhaps the single development that has impacted manufacturing more quickly and significantly than any previous technology is the digital computer 主语： the development 系动词： is 表语 : digital computer 关系词： that 定语从句： has impacted manufacturing more quickly and significantly than any previous technology Perhaps the single development that has impacted manufacturing more quickly and significantly than any previous technology is the digital computer

The rationale for CAD/CAM is similar to that used to justify any technology-based improvement in manufacturing 主语 ： the rationale 谓语 ： is similar to 宾语 ： that 指代 rationale Used to …… 过去分词短语作定语，修饰 that

There are also other reasons why a company might make a conversion from manual processes to CAD/CAM. There be 句型 Why 引导的定语从句修饰 reasons 翻译：还有如下一些因素促使一家公司将手工 加工方式改造为应用 CAD/CAM 系统来进行生产

Input devices are generally used to transfer information from a human or storage medium to a computer where “CAD function” is carried out. 主语： input devices 谓语： are used to transfer 宾语： information 关系副词： where 定语从句： where "CAD function” is carried out

exercises Fill in the blanks according to the text. 1.computer-aided design systems are powerful tools and are used in the ______ design and ________ modeling of products and components. 2. There are several good reason using a CAD system to support the engineering design function: to eliminate _________caused by hand-copying of drawings and __________ between drawings. 3. This combination allows the ______ of information from the design stage into the stage of planning for the manufacturing of a product, without the need to _______ the data on part geometry. 4. CAXA is the ______ CAD/CAM software. graphicsgeometric inaccuracies inconsistency transfer reenter domestic

Assignment Answer the following questions 1. What is the definition of CAD? 2. What is the definition of CAM? 3.What is the rationale of CAD/CAM? 4.What does the CAD/CAM hardware involve? 5. How many applications of CAD/CAM are there?