iyzAAA英语复习资料

英语复习资料一、英译汉 第一课1 The major part of a machine is the mechanical system. And the mechanical system is decomposed into mechanisms, which can be further decomposed into mechanical components. 机械的主要组成部分是机械系统，机械系统可分解成机构，机构又可以进一步分解成机械零件。2 Definition of the problem must include all the specifications for the thing that is to be designed. Obvious items in the specifications are the speeds, feeds, temperature limitations, maximum range, expected variation in the variables, and dimensional and weight limitations. 问题的定义必须包括设计任务的所有技术条件，其中重要的要素有速度、进给量、温度限制、最大范围，以及变量、尺寸和重量的预期变化范围。第二课3 The motion specific property of mechanism chiefly depends on the relative size between the members, and the character of motion pairs, as well as the mutual disposition method etc. 机构的运动特性主要取决于构件间的相对尺寸、运动副的性质以及相互配置方式等。4 The plane four-bar linkage, the plate cam and driven parts, and the slider-crank mechanism are familiar examples of planar mechanism. The vast majority of mechanism in use today is planar. 平面四连杆机构、平面盘形凸轮、从动件及曲柄滑块机构等都是平面机构的常见的例子。目前应用的绝大部分机构都是平面机构。第三课5 Gear types are determined largely by the disposition of shafts; This means that is a specific disposition of the shafts is required, the type of gear will more or less be fixed. 齿轮的种类一般是根据齿轮轴的排序方式来划分的，这就意味着当轴的排列布置形式决定后，齿轮的类型大致就定下来了。6 worm gears provide the simplest means of obtaining large ratios in a single pair. They are usually less efficient than parallel-shaft gear, however, because of an additional sliding movement along the teeth. 蜗轮蜗杆是用一对齿轮就可以提供较大的速比的最简单方法，但是由于沿着齿面方向存在滑动现象，所以蜗轮蜗杆的传动总是比平行轴传动的齿轮效率低。（7） When assembled, the pins are a free fit in the bushings and rotate slightly, relative to bushings when the chain goes on and leaves a sprocket. 装配好后，销轴与套筒之间为自由配合，随着链条在链轮上传动，销轴可相对于套筒作轻微的转动。第四课（8） Virtually all machines contain shafts. The most common shape for shafts is circular and the cross section can be either solid or hollow (hollow shafts can result in weight saving). 实际上，几乎所有的及其中都装有轴。轴最常见的形状是圆形，其截面可以是实心的，也可以是空心的（空心轴可以减轻重量）（9） Another important aspect of shaft design is the method of directly connecting one shaft to another. This is accomplished by devices such as rigid and flexible couplings. 在轴的设计中，轴与轴之间的链接方法是要点考虑的，可由刚性或弹性联轴器来实现。10 However, in the case of bearings, the reduction of friction is one of the prime considerations: Friction results in loss of power, the generation of heat, and increased wear of mating surfaces. 然而，设计轴承时，减小摩擦是要考虑的基本因素之一，因为摩擦会导致功率下降、发热和配合表面的磨损。第五课11 As a common language of engineering, the drawing is use to direct the production and make the technical interchange.So,it is necessary to specify, in a unified way, drafting practices, such as the layout of drawings, dimensioning, and so on. 作为工程界的共同语言，图样是用来指导生产和交流技术的。因此，必须对制图的各个方面，如图样格式、图样画法、尺寸标注等，做出统一规定。（11） the drawing is the primary medium for developing and communicating technical ideas. Engineering drawings provide an exact and complete description of objects. In addition to a description of the shape of an object, an engineering drawing gives all further information needed to manufacture the object draw, such as dimensions, tolerances, and so on. 图样是开发和交流思想的主要工具。工程图样可为零件提供准确的=而完整的描绘。除了物体的形状外，工程图样还给出制造所需的全部资料，如尺寸、公差等。第六课12 Perhaps the single development that has impacted manufacturing more quickly and significantly than any previous technology is the digital computer. Computers are being used increasingly for both design and detailing of engineering components in the drawing office. 与以前出现的任何科学技术相比，对工程制造业冲突最快，影响更大的是数字计算机。如今计算机已被广泛应用在工程产品的设计中。第七课13 The typical design process involves iterations during which the geometry of the part(s) is altered. In general, each iteration also involves some form of analysis in order to obtain viable engineering results. 零部件结构的优化设计过程往往需要进行多步代计算，在整个过程中，零部件的几何外形不断变化，优化。在每一步代计算中要进行一定的分析，以便得到与工程实际较为相符的设计结果。14 During the design process, the engineer may alter parameters or characteristics of the CAD and/or FEA models, including some of the physical dimensions, the material or how the part or assembly is loaded or constrained. 在设计过程中，工程师可能需要改变CAD或FEA模型的一些参数或特性，如零部件或装配体的几何尺寸、材料参数以及约束和加载的状况。第九课15 Control of dimensions is necessary in order to ensure assembly and interchangeablility of components. 为了确保零件的装配和互换性，有必要控制尺寸，对于影响间隙和过盈配合的关键尺寸应指定公差。第十课16 A numerical control system consists of the following three basic components: Program instructions. Machine control unit. Processing equipment. 一个数控系统由一下的三部分组成： 程序指令、加工控制单元、制造装备。17 In all interpolations, the path controlled is that of the center of the tool. Compensation for different tools, different diameter tools, or tools wear during machining, can be made in the NC program. 在所有的插补方法中，路径控制是以刀具的旋转中心为标志，在数控程序中对类型不同，直径不同的刀具以及在加工过程的不同刀具磨损量给予不同的补偿。18 Processing instructions pertain to spindle speeds feeds, tools, and so on. Travel instructions pertain to the type of interpolation and slow or rapid movements of the tool or worktable. 加工指类令用于定义主轴转速、进给。刀具转速等。传送指令用于定义刀具或工作台的运动速度和插补的类型等。第十二课19 By applying a stress that exceeds the original yield strength of metallic material, we have strain hardened or cold worked the metallic material, while simultaneously deforming it. 通过对材料施加大于屈服强度应力，可以使其产生变硬或进行冷却加工的同时产生变形。20 Hot wor