机械专业英语董建国 第2章

Unit 2
3. The work is given the primary motion while the tool is fed
continuously.
工件做主运动，而刀具则做连续进给运动。
“be given” (被给)常可译成“得到”、“获得”。例如：
I am given a book. 我得到一本书。 In turning, the work is given the primary motion. 车削时，工件获得主运动。
EXERCISES
1．Discuss the following questions in English:
(1) What is the primary motion? (2) What is the feed motion? (3) What is turning? (4) What is drilling?
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TEXT READING MATERIAL
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TEXT
Primary Motion and Feed Motion
Broadly speaking，two kinds of relative motion must be provided
by a machine tool—the primary motion and the feed
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2．Use English for replacing Chinese or use Chinese for
replacing English.
(1) 相对运动 (2) 加工表面 (3) 机械制造 (4) Desired geometry (5) A machining operation (6) Rotating a cutting tool
逐步地
小部分 线性运动
lateral feeding movement
return stoke take … into consideration
横向进给运动
返回行程 对……加以考虑，考虑到
by comparison
比较起来
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NOTES
1. Broadly speaking，two kinds of relative motion must be provided by a machine tool— the primary motion and the feed motion． 概括地讲，机床必须提供两种相对运动——主运动与进给运动。 “Broadly speaking”是插入语，这里可译为“一般讲”。破 折号后面的内容“the primary motion and the feed motion”实际上 是解释“two kinds of relative motion”，不要认为破折号在“a machine tool”后面，就误以为“the primary motion and the feed motion”是解释“a machine tool”的。在英语中，很多场合使用被 动语态，宾语放在了前面，而主语放在了后面，造成了中心词 与解释中心词的内容从形式上看被分开了，因而在翻译时要特 别引起注意。
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Miss Li: What sort of job do you like to do? John： I would like to be milling worker. I think I can do my best to it. Miss Li: Great! What time can you start to work? John： Anytime. Miss Li: Very nice. How much do you expect in salary? John： 800 yuan. Miss Li: OK! Please fill in this form. If anything turns, I’ll contact with you. John： Thank you! Miss Li: You’re welcome.
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Fig. 2-1 Primary motion and feed motion
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LEARN TO SPEAK
John： Miss Li: How do you do! My name is John. How do you do!
John：
Miss Li:
Are there any vacancies in your factory?
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proportion
linear
[prE5pC:F(E)n]
[5lInIE(r)]
n. 比例，部分
adj. 直线的，线性的
motionless
lateral
[5mEJF(E)nlIs]
[5lAtEr(E)l]
adj. 不动的，静止的
adj. 横(向)的
return
kinematic relationship reverse
在所有的金属中，钢在工程上用得最普遍。
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有时把句子从英文翻译成中文时要根据上下文的意思 适当地加词，以使句子读起来通俗易懂。本句在翻译时， 在两种功用的前面加上了一个定语“加工出一个孔的”， 虽然本句中没有对应的英文，但从上一句讨论的钻削中， 我们就可以知道是在讲加工一个孔。
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proceed by steps or continuously and absorb a small proportion of the
total power．
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Turning means machining a piece of rotating metal by pressing a hardened cutting tool against it. The work is given the primary motion while the tool is fed continuously. The process of planing and shaping is removing metal in a series of straight cuts. In planing, the work is given a linear motion while the tool remains motionless during the cutting stroke and is provided with a lateral feeding movement during the return stroke. In the case of the shaper, the kinematic relationship between work and tool is reversed; however, the cutting action principle is the same. Drilling consists of rotating a cutting tool and advancing the tool along its own axis into a stationary work-piece to produce a round hole. Of the two functions， advancing the tool along its axis is the major consideration in the design of drilling machines. Rotating the drill is, by comparison, a simple matter.
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2. As a rule，the primary motion absorbs most of total power which is required to perform a machining operation. 通常，主运动要消耗切削加工所需要的总功率中的大部分。 “as a rule”作为一个整体，其含义为“通常”。“which” 引导的是定语从句，用来进一步解释“total power”是用来干 什么的。
adv. 相反
n. 原则，原理
[Ed5vB:ns; (?@) Ed5vAns] v. 前进，推进 [5AksIs] [5AksIz] [raJnd] n. 轴 n. 轴(复数) adj. 圆的
adv. 围绕着
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consideration [kEnsIdE5reIF(E)n] comparison matter mechanical [kEm5pArIs(E)n] [5mAtE(r)] [mI5kAnIk(E)l] n. 考虑 n. 比较 n. 事件，物质 adj. 机械的 n. 制造业 n. 空缺
motion．Combination of these two motions will lead to a chip removal and the creation of machined surface with desired geometry. As a rule，the primary motion absorbs most of total power which is required to perform a machining operation. The feed motion may
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4. Of the two functions，advancing the tool along its axis is the
major consideration in the design of drilling machines.
在这两种功用中，使钻头沿自身的轴线进给是设计钻床时主 要考虑的问题。 “Of” 放在句首表示“在……中”，例如： Of all machine tools, the lathe is the most common one. 在所有的机床中，车床是最普通的一种。 Of all metals, steel is the most widely used in engineering.
Yes. We need some new workers. What subject
was your major? John： I majored in mechanical manufacturing, and I
think IBiblioteka am good at operating milling
machine.
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NEW WORDS AND EXPRESSIONS
primary 的 broad broadly removal geometry absorb proceed continuous continuously [5praImErI] [brC:d] [rI5mu:v(E)l] [dVI5RmItrI] [Eb5sC:b] [prE5si:d] [kEn5tInjJEs] adj. 第一位的，初级 adj. 宽的 adv. 概括地，大致地 n. 移动，切除 n. 几何形状，几何学 vt. 吸收，吸引 vi. 进行，发生 adj. 连续的，持续的 adv. 连续不断地
manufacturing [9mAnjJ5fAktFErIN] vacancy [5veIkEnsI]
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primary motion broadly speaking lead to as a rule 主运动 概括地讲 导致 通常，照例
by steps
a small proportion of linear motion
[rI5tE:n]
[kB:nI5mAtIk] [rI5leIFEnFIp] [rI5vE:s]
v.&n. 返回，退回
adj. 运动学(上)的 n. 关系 v.&n. 相反，背面，倒退
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adj. 相反的
reversely
principle advance axis axes round prep. 围着 [5prInsIp(E)l]