机械工程专业英语
【The branch of scientific analysis which deals with motions time and forces is called mechanics and is made up of two parts statics and dynamics】. 对运动、时间和作用力进行科学分析的分支称为力学，它由静力学和动力学俩部分组成。【Statics deals with the analysis of Stationary ,i .e.,those in which time is not a factor,and dynamics deals with systems which change with time 静力学对静止系统进行分析，即在其中不考虑时间这个因素，动力学对随时间而变化的系统进行分析。【Forces are transmitted into machine members through mating
surfaces ,e.g.,form a gear to a shaft or form one gear through meshing teeth to another gear,from a V belt to a pulley,or from a cam to a follower】.力通过接触表面传到机器中的各构件上。例如，从齿轮传到轴或者从齿轮通过与其啮合的轮齿传到另一个齿轮，从V带传到带轮，或者从凸轮传到从动件。【It is necessary to know the magnitudes of these forces for a variety of Reasons】由于很多原因，人们必须知道这些力的大小。【The distribution of the forces at the boundaries or mating surfaces must be reasonable and their intensities must be within the working limits of the materials composing thesurfaces】这些力在边界或在接触表面的分布必须合理，它们的大小必须在构成配合表面的材料的工作极限以内。【For example if the force operating on a journal bearing becomes too high it will squeeze out the oil film and cause metal-to-metal contact overheating and rapid failure of the bearing】.例如，如果作用在一个滑动轴承上的力太大，它就会将油膜挤出，造成金属与金属的直接接触，产生过热和使轴承快速失效。【If the forces betweens gear teeth are too large the oil film may be squeezed out from between them】.如果齿轮相啮合的齿与齿之间的力过大，就会将油膜从齿间挤压出来。【This could result in flaking and spalling of the metal noise rough motion and eventual failure】这会造成金属表层的碎裂和剥落，噪音增大，运动不精确直至报废。【In the study of mechanics we are principally interested in determining the magnitude direction and location of the Forces】.在力学研究中，我们主要关心力的大小、方向和作用点。
Virtually all machines contain shafts.实际上，几乎所有的机器中都装有轴。The most common shape for shafts is circular and the cross section can be either solid or hollow.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。Rectangular shafts are sometimes used, as in screwdriver blades, socket wrenches and control knob stems.有时也采用矩形轴，例如，螺丝刀的头、套筒扳手和控制旋转的杆。A shaft must have adequate tensional strength to transmit torque and not be overstressed.为了在传递扭矩时不发生过载，轴应该具有适当的抗扭强度。It must also be torsion ally stiff enough so that one mounted component does not deviate excessively from its original angular position relative to a second component mounted on the same shaft.轴还应该具有足够的抗扭刚度，以确保同一个轴上的两个传动零件之间的相对转角不会过大。Generally speaking, the angle of twist should not exceed one degree in a shaft length equal to 20 diameters.一般来说，当轴的长度等于其直径的20倍时，扭转角不应该超过1度Shafts are mounted in bearing and transmit power though such devices as gears, pulleys, cams and clutches.轴安装在轴承中，通过齿轮、皮带轮、凸轮和离合器等零件传递动力。These devices introduce forces which attempt to bend the shaft ;通过这些零件传来的力可能会使轴产生弯曲
变形hence, the shaft must be rigid enough to prevent overloading of the supporting bearing . 因此，轴应该有足够的刚度以防止支承轴承受力过大。In general, the bending deflection of a shaft should not exceed 0.5mm per meter of length between bearing supports.总而言之，在两个轴承支承之间，轴在每米长度上的弯曲变形不应该超过0.5mm
The first step in the manufacture of any product is design, which usually takes place in several
distinct stages (a) conceptual (b) functional(c)production design.制造任何产品的第一步都是设计。设计通常可以分为几个明确的阶段：a.概念设计b.概念设计c.生产设计。During the conceptual-design stage, the designer is concerned primarily with the functions the product is to fulfill.在设计概念阶段，设计者着重考虑产品应该具有的功能。Usually several concepts are visualized and considered, and a decision is made either that the idea is not practical or that the idea is sound and one or more of the conceptual designs should be developed further通常要设想和考虑几个方案，然后决定这种想法是否可行;如果可行，则应该对其中一个或几个方案作进一步的改进Here, the only concern for masteries is that materials exist that can provide the desired properties在此阶段，关于材料选择唯一要考虑的问题是：是否有性能符合要求的材料可供选用If no such materials are available, consideration is given as to whether there is a reasonable prospect that new ones could be developed within coat and time limitations如果没有的话，是否有较大的把握在成本和时间都允许的限度内研制出一种新材料
At the production-design stage, the primary concern relative to materials should be that they are specified fully, that they are compatible with, and can be processed economically by, existing equipment, and that they are readily available in the needed quantities 在生产设计阶段中，与材料有关的问题是应该把材料完全确定下来，使它们与现有的设备相适应，能够利用现有设备经济的进行加工，而且材料的数量能够比较容易的保证供应。【A mechanism has been defined as "a combination of rigid or resistent bodies so formed and connected that they move upon each other with definite relative motion.】
机构被定义为:"是由刚体或者有承载力的物体连接而形成的组合体，它们在运动时彼此之间应该具有确定的相对运动。
【Mechanisms form the basic geometrical elements of many mechanical devices including automatic packaging machinery,fixtures,mechanical toys,textile machinery,and others.】机构是构成许多机械设备的基本几何单元，这些机械设备包括自动包装机、夹具、机械式玩具、纺织机等等。【A mechanism typically is designed to create a desired motion of a rigid body relative to a reference Member】机械设计的目的通常是使一个刚体相对某一参考构件产生所需要的相对运动。【Kinematic design of mechanisms is often step in the design of a complete machine.】机构的运动设计通常是设计一台完整的机器的第一步。【When forces are considered the additional problems of dynamics bearing loads,stresses,lubrication,and the like are introduced ,and the larger problem becomes one of machine design.】在考虑力的作用时，应该考虑力学、轴承载荷、应力、润滑等一系列问题。在所考虑的问题的范围扩大之后，机构设计就变成了机器设计。【The function of a mechanism is to transmit or transform motion from one rigid body to another as part of the action of a machine】作为机器的一个组成部分，机构的作用是在刚体之间传递或转换运动。【There are three types of common mechanical devices that can be used as basic elements of a mechanism.】常用的基本机构有以下三种:
【Gear systems,in which toothed members in contact transmit motion between rotating Shafts】齿轮机构，在这种机构中，各转轴之间的运动由相互啮合的齿轮来传递。
【Gears normally are used for the transmit motion with a constant angular velocity
ratio,although noncircular gears can be used for nonuniform transmission of motion.】
齿轮通常用来传递角速度比为常值的运动，但是非圆齿轮可以用来传递角速度比为变数的运动。【Cam systems,where a uniform motion of an input member is converted into a nonuniform motion of the output member】凸轮机构，在这种机构中，输入件的等速连续运动被转换成输出件的不等速运动。【The output motion may be either shaft rotation,slider translation,or other follower motions created by direct contact between the input cam shape and the follower】输出的
运动可以是轴的转动、滑块的移动、或者其它从动件的运动。这些运动都是使从动件与作为输入件的凸轮的轮廓的直接接触而产生的。【The kinematic design of cams involves the analytical or graphical specification of the cam surface shape required to drive the follower with a motion that is a prescribed function of the input motion.】凸轮的运动设计就是采用解析法或者图解法来确定凸轮的轮廓形状，使其能够带动从动件实现输出运动运动是输入运动的指定函数这一功能。Automatic Tracer Lathes 自动仿形车床Since surface roughness depends greatly upon material turned, tooling, and feeds and speeds employed, minimum tolerances that can be held on automatic tracer lathes are not necessarily the most economical tolerances. 因为零件的表面粗糙度在很大程度上取决于工件材料、刀具、进给量和切削速度，采用自动仿形车床加工所得到的最小公差不一定是最经济的公差。In some cases, tolerances of ±0.05mm are held in continuous production using but one cut. 在某些情况下，在连续生产过程中，只进行一次切削加工时的公差可以达到±0.05mm。Groove width cam be held to ±0.125mm on some parts. 对于某些零件，槽宽的公差可以达到±0.125mm。On high-production runs where maximum output is desirable, a minimum tolerances of ±0.125mm is economical on both diameter and length of turn. 在希望获得最大产量的大批量生产中，进行直径和长度的车削时的最小公差值为±0.125mm是经济的。
Milling铣削
With the exceptions of turning and drilling, milling is undoubtedly the most widely used method of removing metal. 除了车削和钻削，铣削无疑是应用最广泛的金属切削方法。Well suited and readily adapted to the economical production of any quantity of parts, the almost unlimited versatility of the milling process merits the attention and consideration of designers seriously concerned with the manufacture of their product.铣削非常适合于而且也易于应用在任何数量的零件的经济生产中。在产品制造过程中，许许多多种类的铣削加工是值得设计人员认真考虑和选择的。As in any other process, parts that have to be milled should be designed with economical tolerances that can be achieved in production milling.与其他种类的加工一样，对于进行铣削加工的零件，其公差应该被设计成铣削生产所能达到的经济公差。If the part is designed with tolerances finer than necessary, additional operations will have to be added to achieve these tolerances---and this will increase the most of the part.如果零件的公差设计得比需要的要小，就需要增加额外的工序，以保证获得这些公差---这将增加零件的成本。Meal-cutting processes are extensively used in the manufacturing industry. 金属切削加工在制造业中得到了广泛的应用。They are characterized by the fact that the size of the original workpiece is sufficiently large that the final geometry can be circumscribed by it,其特点是工件在加工前具有足够大的尺寸，可以将工作最终的几何形状尺寸包容在里面。and that the unwanted material is removed as chips , particles, and so on. 不需要的材料以切屑、颗粒等形式被去除掉。The chips are a necessary means to obtain the desired tolerances, and surface roughness. 去除切屑量多少不一，可能占加工前工件几何形状，尺寸公差和表面粗糙度的必要手段The amount of scrap may vary from a few percent 70%-80% of the volume of the original work material切屑量多少不一，可能占加工前工作体积的百分之几到70%-80%不等。Owing to the rather poor material utilization of the metal-cutting processes, the anticipated scarcity of materials and energy, and increasing costs, the development in the last decade has been directed toward an increasing application of metal-forming processes. 由于在金属切削加工中，材料的利用率相当低，加之预测到材料到材料和能源的短缺以及成本的增加，最近十年来，金
属成形中国式的应用越来越多。However, die costs and the capital cost of machines remain rather high; consequently, metal-cutting processes are, in many cases, the most economical, in spite of the high material waste, which only has value as scrap. 然而，由于金属成形加工的模具成本和设备成本仍然很高，因此尽管金属切削加工的材料较高，在许多情况下，它们仍然是最经济的。Therefore, in spite of the high material waste, which only has value as scrap .therefore, it must be expected that position in manufacturing. Furthermore, the development of automated production systems has progressed more rapidly for metal-cutting processes than for metal-forming processes由此可以预料，在最近几年内，金属绿削加工在制造业中仍将占有重要的位置。而且，金属切削加工抱着自动生产系统的发展要比金属成形加工的自动生产系统的发展要快得多In turning the primary motion is provided by the rotation of the workpiece, and in planning it is provided by the translation of the table; in turning the feed motion is a continuous translation of the tool, and in planning it is an intermittent translation of the tool. Figure 27.1 shows basic machining parameters in turning 车削时，工件的回转运动是主动龙门刨床刨削时，工作台的直线运动是主运动。车削时，刀具连续的直线运动是进给运动；而在龙门刨床刨削中，刀具间歇的直线运动是进给运动。车削加工抱着基本参数如图The technique of dimensioning parts within a required range of variation to ensure interchangeability is called tolerancing . Each dimension is allowed a certain degree of variation within a specified zone , or tolerance . For example , a part's dimension might be expressed as 20±0.05，which allows a tolerance (variation in size ) of 0.10 mm .给零件标注尺寸使其在一个规定的区间内变动，以保证它们具有互换性的技术称为公差技术。允许每个尺寸在规定范围内具有一定的变动量，称为公差。例如，一个零件的尺寸可以被表示成20±0.05，其公差（尺寸变动量）为0.10mm。Tolerance is an undesirable , bet permissible , deviation from a desired , theoretical dimension in recognition that no part can be made exactly to a specified dimension , except by chance , and such is neither necessary nor economical .由于将零件精确地加工到某一指定的尺寸（除了碰巧外）是不可能，而且这样做是既不必要也是不经济的，因而相对于所需的理论尺寸，公差是一个既不希望存在，但又是允许存在的偏差。Fit:the tightness between two assembled parts . The three types of fit are: clearance , interference and transition.
配合：两个装配在一起的零件之间的松紧程度。可以把配合分为三类：间隙配合，过盈配合，过渡配合。Without needing to know how to operate a particular machine to attain the desired degree of surface roughness , there are certain aspects of all these methods which should be understood by the design engineer . Knowledge of such facts as degree of roughness obtained by any operation , and the economics of attaining a smoother surface with each operation , will aid him in deciding just which surface roughness to specify .设计工程师并不需要知道如何操纵一台专门的机床去获得所需要的表面粗糙度，但是他应该清楚在这些加工方法的某些情况。各种工序所能得到的表面粗糙度数值的大小，以及采用每一种工序来获得更为光滑表面的经济性方面的知识都会帮助设计工程师决定采用何种表面粗糙度。Because of its simplicity , the arithmetical Ra has been adopted internationally and is widely used . The applications of surface roughness Ra are described in the following paragraphs . 由于其简单，算术平均粗糙度Ra 在全世界范围内得到了广泛的应用。下面各段中介绍了表面粗糙度Ra 的应用实例。The conventional manufacturing processes in use today for material removal primarily rely on Conventional forming operations are performed with the energy from electric motors , hydraulics ,
and gravity 在目前所采用的常规制造工艺中，材料的去除是依赖于电动机和硬的刀具材料进行的，诸如锯断，钻孔和拉削。常规的成型加工是利用电动机，液压和重力所提供的能量进行的。. Likewise , material joining is conventionally accomplished with thermal energy sources such as burning gases and electric arcs. 同样材料连接的常规做法是采用诸如燃烧的气体和电弧等热能进行的。In contrast , nontraditional manufacturing processes harness energy sources considered unconventional by yesterdays standards 与之相比，特种加工工艺采用按照以前的标准来说不是常规的能源。Material removal can now be accomplished with electrochemical reactions , high-temperature plasmas , and high-velocity jets of liquids and abrasives .现在材料的去除可以利用电化学反应，高温等离子, 高速液体和磨料射流。Materials that in the past have been extremely difficult to form , ,are now formed with magnetic fields , explosives , and the shock waves form powerful electric sparks . 过去非常难进行成型加工的材料，现在可以利用大功率的电火花所产生的磁场，爆炸和冲击波进行成型加工。Material-joining capabilities have been expanded with the use of high-frequency sound waves and beams of electrons . 采用高频声波和电子束可以使材料的连接能力有很大的提高。Computer-Aided Process planning计算机辅助工艺过程设计
What may be even more disturbing is that a process plan developed for a part during a current manufacturing program may be quite different form the plan devdloped for the same or similar part during a previous manufacturing program and it may never be used again for the same or similar part.在目前的制造过程中的一个更为混乱的现象是，对于一个零件来说，现在所编制的工艺规程可能与以前在制造过程中所编制的同一个零件或者相似零件的工艺规程相差很多，而且这个工艺规程可能再也不会应用于同一个零件或者相似零件。That represents a lot of wasted effor and produces a great may inconsistencies in routing, tooling, labor requirements,costing,and possibly even purchase requirements.
这说明很多工作成果都被浪费了，而且在工艺路线、工艺装备、对工人的要求和成本等方面都不一致，甚至对外购件的要求都不一样。Of course, process plans should not necessarily remain static. As lot sizes change and new technology, equipment,and ptocesses become available, the most effective way to manufacture a particular part also changes, and thosechanges should be reflected in current process plans released to the shop.当然工艺规程不应该是一成不变的。随着产品批量的变化和新技术、新设备、新的加工方法的出现，加工制造某一特定零件最适当的方法也会发生变化，而且这些变化应该在车间目前使用的加工工艺规程中反映出来。A planner must manage and retrieve a great deal of data and many documents,including established standards, machinability data,machine specifications,tooling inventories,stock availability,and existing process plans.This is primarily an information-handling job, and computer is an ideal companion..工艺人员应当管理和检索大量的数据和很多文件，其中包括：已经建立的标准、可加工性数据、机器的规格、工艺装备的清单、原材料库存量和一些目前正在应用的工艺文件。这主要是一些信息处理工作，而计算机是完成这项工作的一个理想助手。
Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded , written symbolic instructions . 数字控制意味着采用预先录制的、存储的符号指令来控制机床和其他制造系统。Rather than operating a machine tool , an NC technician writes a program that issues operational instructions to the machine tool .一个数控技师的工作不是去操纵机床，而是编写能够发出机床操纵指令的程序。Numerical control was developed to overcome the limitation of human operators , and it has done so . 发展数控技术我为了克服人类操作者的局限性，而且它确定完成了这项工作。Numerical control machines are more accurate than manually operated machines , they can produce parts more uniformly , they
are faster , and the long-run tooling costs are lower . The development of NC led to the development of several other innovations in manufacturing technology :数字控制的机器比人工操纵的机器的精度更高、生产出零件的一致性更好、生产速度更快、而且长期的工艺装备成本更低。数控技术的发展导致了制造技术中其他几项新发明的产生
：
1.Electrical discharge machining . 电火花加工技术
https://www.sodocs.net/doc/b110166559.html,ser cutting 激光切屑
3.Electron beam welding 电子束焊接
There are a variety of definitions of the term industrial robot.有许多关于工业机器人的定义。Depending on the definition used,the number of industrial robot installations worldwide varies widely。采用不同的定义，全世界各地工业机器人装置的数量就会发生很大的变化。Numerous single-purpose machines are used in manufacturing plants that might appear to be robots.在制造工厂中使用的许多单用途机器可能会看起来像机器人。These machines can only perform a single function and cannot be reprogrammed to perform a different function.这些机器只具有单一的功能，不能通过重复编程的方式去完成不同的工作。Such single-purpose machines do not fit the definition for industrial robots that is becoming widely accepted。这种单一用途的机器不能满足人们日益广泛接受的关于工业机器人的定义。An industrial robot is defined by the International Organization for Standardization (ISO) as an automatically controlled,reprogrammable multipurpose manipulator,which may be either fixed in place or mobile for use in industrial applications.国际标准化组织（ISO）对工业机器人的定义为：一种能够自动控制的，可重复编程的多功能机械手，它可以是固定式的也可以是移动式的，应用于工业自动化领域。
There exist several other definitions too,given by other societies,e.g.,by the Robot Institute of America(RIA),the Japan Industrial Robot Association(JIRA),British Robot Association(BRA),and others.The definition developed by RIA is:其他的一些协会，；例如美国机器人协会（BIA），日本的工业机器人协会（JIRA），英国机器人协会（BRA）等都对工业机器人提出了他们各自的定义。由美国机器人协会提出的定义为：
A robot is a reprogrammable multifunctional manipulator designed to move material,parts,tools,or specialized devices through variable programmed motions for the performance of a variety of tasks.机器人是育中用于移动材料、零件、工具或者庄泳装置的，通过可编程序动作来执行多种任务并具有可重复编程能力的多功能机械手。
All definitions have two points in common.They all contain the words reprogrammable and multifunctional. It is these two characteristics that separate the true industrial robot from the various single-prupose machines used in modem manufactuiing firms.
在所有的这些定义中有两个共同点。它们是“可重复编程”和“多功能”这两个词。正是这两个特征将真正的机器人与现代制造工厂中使用的各种单一用途的机器区分开来。The term "reprogrammable"implies two things:The robot operates according to a written program,and this program can be rewritten to accommodate a variety of manufacturing tasks.“可重复编程”这个词以为着两件事：机器人根据编写的程序工作，以及可以通过重新编写程序来使其适应不同种类的制造工作的需要。The term "multifunctional" means that the robot can, through reprogramming and the use of different end-effector, perform a number of different manufacturing tasks. Definitions written around these two critical characteristics have become the accepted definitions among manufacturing professionals.“多功能”这个词以为着机器人通过重复编程
和使用不同的末端执行器，来完成不同的制造工作。围绕着这两个关键特征所撰写的定义已经编程了被制造业的专业人员所接受的定义。The first articulated arm came about in 1951 and was used by the U.S. Atomic Energy commission. In 1954,the first industrial robot was designed by george c. devol. It was an unsophisticated programmable materials handling machine.第一个关节式手臂于1951年被研究出来，供美国原子能委员会使用。在1954年，第一个可以编程的机器人由乔治C。德沃尔设计出来。他是一个不复杂的，可以编程的物料搬运机器人。The first commercially produced robot was developed in 1959.第一个商业化生产的机器人在1959年研制成功。in 1962, the first industrial robot to be used on a production line was installed in the General Motors Corporation. 通用汽车公司在1962年安装了第一个用于生产线上的工业机器人。It was used to lift red-hot door handles and other such car parts from die casting machines in an automobile factory in New Jersey, USA.他在位于美国新泽西州的第一家汽车厂中被用来从压铸中取出红热的车门拉手以及诸如此类的汽车零件。Its most distinctive feature was a gripper that eliminated the need for man to touch car parts just made from molten metal. It had five degrees of freedom (DOF).this robot was produced by Unimation.他最显著的特点是通过采用手爪，避免由人去接触那些刚刚由融化的金属形成的汽车零件。它有五个自由度。它是由万能自动化公司（UNIMA TION）生产的。A major step forward in robot control occurred in 1973 with the development of the T^3 industrial robot by Cincinnati Milacron. The T^3 robot was the first commercially paoduced industrial robot cotrolled by a minicomputer. 在1973年，辛辛那提.米拉克龙公司研究制出T^3工业机器人，在机器人的控制方面取得了重大的进展。Figure 53.1 shows a T^3 robot with all the motions indicated, it is also called jointed –spherical robot.. T^3机器人是第一个商业化生产的采用小型计算控制的机器人。T^3机器人和它的所有运动如图53.1所示，他也可以被称为关节式球面机器人。Since then robotics has evolved in a multitude of directions, starting from using them in welding , painting, in assembly, machine tool loading and unloading, to inspection.从那时起，机器人技术在很多方面都得到了发展，这包括焊接、喷漆、装配、机床上下料和检测。Over the last three decades automobile factories have become dominated by robots. 在过去的三十年中，机器人在许多汽车制造厂中占据了主要地位。Atypical factory contains hundreds of directions, working on line, a vehicle chassis on a conveyor is welded, painted and finally assembled at a sequence of robot stations.在一个工厂中，通常有数以百计的工业机器人工作在全自动生产线上。例如，在一条自动生产线上，车辆底盘装在输送机上。在通过一连串的机器人工作站进行诸如焊接、喷漆和最后的装配等项工作。Mass-produced printed circuit boards (PCBs) are almost exclusively assembled by pick-and-place robots, typically with SCARA manipulators, which pick tiny electronic components, and place them on to PCBs with great accuracy. Such robots can place tens of thousands of components per hour, far surpassing a human in speed, accuracy, and reliability.在印刷电路板的大批量生产过程中，装配工作几乎完全都是采用抓—放型机器人进行的。通常采用平面关节型装配机器人（SCARA），它可以抓取微小的电子元器件以非常高的精度将其放到印刷电路板上。这类机器人每个小时可以放置成千上万哥个元器件，其速度、精度和可靠性都远远超过人类。
机械工程专业英语
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《机械工程专业英语教程》课文翻译
Lesson 1 力学的基本概念 1、词汇： statics [st?tiks] 静力学；dynamics动力学；constraint约束；magnetic [m?ɡ＇netik]有磁性的；external [eks＇t?:nl] 外面的, 外部的；meshing啮合；follower从动件；magnitude [＇m?ɡnitju:d] 大小；intensity强度，应力；non-coincident [k?u＇insid?nt]不重合；parallel [＇p?r?lel]平行；intuitive 直观的；substance物质；proportional [pr?＇p?:??n?l]比例的；resist抵抗，对抗；celestial [si＇lestj?l]天空的；product乘积；particle质点；elastic [i＇l?stik]弹性；deformed变形的；strain拉力；uniform全都相同的；velocity[vi＇l?siti]速度；scalar[＇skeil?]标量；vector[＇vekt?]矢量；displacement代替；momentum [m?u＇ment?m]动量； 2、词组 make up of由……组成；if not要不，不然；even through即使，纵然； Lesson 2 力和力的作用效果 1、词汇： machine 机器；mechanism机构；movable活动的；given 规定的，给定的，已知的；perform执行；application 施用；produce引起，导致；stress压力；applied施加的；individual单独的；muscular [＇m?skjul?]]力臂；gravity[ɡr?vti]重力；stretch伸展，拉紧，延伸；tensile[tensail]拉力；tension张力，拉力；squeeze挤；compressive 有压力的，压缩的；torsional扭转的；torque转矩；twist扭，转动；molecule [m likju:l]分子的；slide滑动; 滑行；slip滑，溜；one another 互相；shear剪切；independently独立地，自立地；beam梁；compress压；revolve (使)旋转；exert [iɡ＇z?:t]用力，尽力，运用，发挥，施加；principle原则, 原理，准则，规范；spin使…旋转；screw螺丝钉；thread螺纹； 2、词组 a number of 许多；deal with 涉及，处理；result from由什么引起；prevent from阻止，防止；tends to 朝某个方向；in combination结合；fly apart飞散； 3、译文： 任何机器或机构的研究表明每一种机构都是由许多可动的零件组成。这些零件从规定的运动转变到期望的运动。另一方面，这些机器完成工作。当由施力引起的运动时，机器就开始工作了。所以，力和机器的研究涉及在一个物体上的力和力的作用效果。 力是推力或者拉力。力的作用效果要么是改变物体的形状或者运动，要么阻止其他的力发生改变。每一种
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机械工程专业英语讲课教案
机械工程专业英语
Lesson1 1、the branch of scientific analysis, which deals with motions, time, and forces, is called mechanics and is made up of two parts, statics and dynamics. Statics deals with the analysis of stationary systems, i.e., those in which time is not a factor, and dynamics deals with systems, which change with time. 对运动时间和作用力作出科学分析的分支成为力学。他由静力学和动力学两部分组成。静力学对静止系统进行分析，即在其中不考虑时间这个引述，动力学对事件而变化的系统进行分析。 2、Any two such forces acting on a body constitute a couple. The arm of the couple is the perpendicular distance between their lines of action, and the plane of the couple is the plane containing the two lines of action. 作用在一个刚体上的两个这样的的里构成一个力偶。力偶臂是这两个条作用线之间的垂直距离，力偶面是包含着两条作用线的平面。 3、Mechanics deal with two kinds of quantities: scalars and vectors. Scalar quantities are those with which a magnitude alone is associated. Examples of scalar quantities in mechanics are time, volume, density, speed, energy, and mass. Vector quantities, on the other hand, possess direction as well as magnitude. Examples of vectors are displacement, velocity, acceleration, force, moment, and momentum. 力学涉及两种类型的量，标量和矢量。标量是那些只有大小的量。在力学中标量的例子有时间、体积、密度、速率、、能量和质量。另一方面，矢量既有大小又有大小又有方向。矢量的例子有位移、速度、加速度、力、力矩、动量。Lesson2（此课后面没翻译，翻译的不太准确谅解） 1 、The turning of a part in a lathe is another example of several forces in action.（as shown in figure1） 车床车削是一些力在起作用的另一个例子。figure1(如图)。 2 、If this workpiece is held between the centers of the lathe, the centers exert a compressive force against the work. 如果这个工件在放在车床中心之间,中心车床对工作产生压力。 3、 Rotary motion is required to drill holes, turn parts in a lathe, mill surfaces, or drive a generator or fan belt. 扶轮运动需要去钻孔，在车床上转换两件,表面,或驱动发电机或风扇皮带 4 、Harmonic and Intermittent Motion（谐和运动和间歇运动）: Any simple vibration, such as the regular back, and forth movement of the end of a pendulum, is simple harmonic motion. Lesson4 1 、Virtually all machines contain shafts. The most common shape for shafts is circular and the cross section can be either solid or hollow. 仅供学习与交流，如有侵权请联系网站删除谢谢2
研究生机械工程专业英语考试必背单词
研究生机械工程专业英语考试必背单词 Modified by JACK on the afternoon of December 26, 2020
单词 Lesson 1 Gear 齿轮, 传动装置 Bearing 轴承 Cams 凸轮 Cams and followers 凸轮和从动件 Couple 力偶 mechanics 力学 statics 静力学，静止状态 dynamics动力学，原动力，动力特性constraint forces 约束力 applied forces 作用力 Electric , magnetic, and gravitational forces 电,磁,重力 mating surface 啮合表面,配合表面,接触面meshing 啮合，咬合，钩住 meshing teeth 啮合齿 journal bearing 滑动轴承，向心滑动轴承metal-to-metal contact 金属 - 金属接触Overheating 过热 failure 失效 flaking 薄片，表面剥落，压碎 Spall 削，割，剥落，脱皮 noise 噪音 rough motion运动不精确 inertia惯性 particle 质点 rigid body刚体 deformable可变形的，应变的 deformable Body 变形体 Scalar 数量的，标量的 Vectors矢量 Density密度 Mass质量 Displacement位移 Velocity速度 Acceleration加速度 Moment力矩，弯矩 Momentum动量，冲量 Lesson 2 Compressive压缩的，有压力的 Turning 车削 Rectilinear直线的 micrometer 千分尺又称螺旋测微器 Power hacksaws 弓锯床 Shaper牛头刨床 Thread 螺纹 Work：功 muscular action肌肉动作 mechanical motion机械运动 stretch an object拉伸对象 tensile force：拉力 in tension：受拉 compressive force：压力 torsional force：扭力 torque：扭矩 shearing force ：剪切力 twist an object扭曲对象 Slide滑，脱落 Slip滑动，滑移 in compression受压 turning of a part对一个零件进行车削加工wedging action:楔入作用 chip ：切屑 centers of the lathe车床的顶尖 lathe dog车床夹头 centrifugal force ：离心力 grinding wheel ：磨削砂轮 bonding agent ：粘合剂 abrasive particle：磨料颗粒 centrifuge-type machines离心式机械Centrifuge离心机，离心作用 Centrifugal force principles离心力原理centripetal force ：向心力 rotary motion:回转运动 rectilinear motion：直线运动 hand tool手工工具 power tool动力工具 feed：进给 shaping：采用牛头刨床（shaper)进行刨削加工power saw：弓锯床，弓式锯床 the screw of a micrometer 意为“千分尺中的螺杆”harmonic and intermittent motion ：谐和运动和间歇运动 simple harmonic motion ：简谐运动
(完整版)机械工程专业英语词汇
陶瓷ceramics 合成纤维synthetic fibre 电化学腐蚀electrochemical corrosion 车架automotive chassis 悬架suspension 转向器redirector 变速器speed changer 板料冲压sheet metal parts 孔加工spot facing machining 车间workshop 工程技术人员engineer 气动夹紧pneuma lock 数学模型mathematical model 画法几何descriptive geometry 机械制图Mechanical drawing 投影projection 视图view 剖视图profile chart 标准件standard component 零件图part drawing 装配图assembly drawing 尺寸标注size marking 技术要求technical requirements 刚度rigidity 内力internal force 位移displacement 截面section 疲劳极限fatigue limit 断裂fracture 塑性变形plastic distortion 脆性材料brittleness material 刚度准则rigidity criterion 垫圈washer 垫片spacer 直齿圆柱齿轮straight toothed spur gear 斜齿圆柱齿轮helical-spur gear 直齿锥齿轮straight bevel gear 运动简图kinematic sketch 齿轮齿条pinion and rack 蜗杆蜗轮worm and worm gear 虚约束passive constraint 曲柄crank 摇杆racker 凸轮cams
机械工程专业英语教程第三版lesson25
机械五班王乘龙 Lesson 25 Computer Graphics(Reading Material) The term computer graphics refers to the entire spectrum of drawing with the aid of a computer，from straight lines to color animation．An immense range of artistic capabilities resides under the heading of computer graphics and drafting is just one of them． Computer graphics was originally associated with the field of electronics．Companies directly involved in electronics design and manufacturing were the first to experiment and work with computer graphics．As they tested equipment and software，new demands arose that required changes and advances in both hardware and software．Equipment and programs got better，faster，more powerful，less expensive，colorful，and fun to operate．The potential for this new computer development was endless．And as engineers and drafters learned to work with the new tools in a technically demanding atmosphere，artists were using the new tools in an atmosphere of unlimited structure．We see the structure and freedom brought by engineers and artists to computer graphics as we watch animated television network．Complex mathematical
机械专业英语试题及答案精编WORD版
机械专业英语试题及答案精编W O R D版 IBM system office room 【A0816H-A0912AAAHH-GX8Q8-GNTHHJ8】
学院院长（系 主任） （签字）
C. degradation…corrosion D. corrosion… degradation 12. Most frames _______ cast iron, weld steel, composition, or concrete. A. are made from B. are made up of C. was produced by D. was consist of 13. Rotating shafts particularly those that run at high speeds, must be designed to avoid operation at speeds. A . low B .overload C. critical D. hollow 14. Although cast iron is a fairly cheap material, each casting requires a . A. pattern B. model C. mold D. patent 15. The term is used to describe joints with surface contact, as with a pin surrounded by a hole. A. high pair B. low pair C. surface pair D. rotary pair 二、完型填空（在每个小题四个备选答案中选出一个正确答案，本大题共15小题，每小题1分，总计15分） The term shaft usually refers to a relatively long member of round cross section that rotates and transmits power. One or more members such as gears, sprockets, pulleys, and cams are usually (16) to the shaft by means of pins, keys, splines, snap rings, and other devices. These latter members are among the “associated parts” considered in this text, as are couplings and universal joint, which serve to (17) the shaft to the source of power or load.
机械工程专业英语单词
Lesson 1 Basic Concepts in M e c h a n i c s机械学的基本概念mechanics n.力学 modify v.修改，调解，变更manageable a.可控制【管理】的incline v.（使）倾斜 ramp n.斜板，斜坡【道】slope v.（使）倾斜 friction n.摩擦 roll v.滚动 multiplier n.放大器，乘法器broom n.扫帚 convert v.转变【化】 handle n.手柄【把】 sweep v.扫荡【描】，掠过efficiency n.效率 gauge vt.测【计】量，校验bearing n.轴承 ideal mechanical advantage 理想的机械效益 neglect vt.忽略Lesson 2 Basic Assumption in Plasticity Theory 塑性理论的基本假设 assumption n.假定 plasticity n.塑性 investigate v.调查，研究deformation n.变形 metal forming process 金属成型工艺【过程】 strain (rate) n.应变【速率】strength n.强度 stress n.应力 yield stress 屈服应力 flow stress 流动应力 tensile stress 拉【伸】应力compressive stress 压【缩】应力shear stress 剪【切】应力geometry n.几何形状 elastic a.弹性的 springback n.回弹 bending n.弯曲，折弯
《机械工程专业英语》测试题(18-22)含答案
《机械工程专业英语》测验题(18-22) 将下列词组译成汉语 the base circle（基圆） the pitch curve（啮合曲线） the contact force（接触力） the intermittent motion（间歇运动）the common normal（公法线） the conjugate profiles（共轭齿廓） the cycloidal profiles （摆线齿形） the involute profiles（渐开线齿形）the spur gear（直齿轮） the herringbone gears（双螺旋齿轮）the face gear（端面齿轮） the radial distance（径向距离） the addendum circle（齿顶圆） The tooth thickness（齿厚） the tooth space（齿间隙） the cap screws（螺钉） the setscrews（固定螺丝钉） the engineering graphics（工程力学）mechanical design（机械设计） the installation techniques（安装技术）the bolted joint（螺栓连接） the hardened washers（强化垫圈）the fatigue resistance（抗疲劳强度）the modulus of elasticity（弹性模量）the antifriction bearing（减摩轴承）the rolling bearing（滚动轴承） the rolling contact （滚动接触） the sliding contact（滑动触电） the corrosion resistance（抗腐蚀性）the machining tolerances（加工公差）the fatigue loading（疲劳载荷） the radial loads（径向负荷） the thrust loads逆负荷 the ball bearing球轴承 the roller bearing滚子轴承 the single-row bearings单沟轴承 the double-row bearing双沟轴承 the needle bearing滚针轴承 the bearing life轴承寿命 The rating life额定寿命
最新机械工程专业英语第二版必考翻译(完整版)
1.With low-power machinery or vehicles the operator can usually apply sufficient force through a simple mechanical linkage from the pedle or handle to the stationary part of the brake. In many cases, however, this force must be multiplied by using an elaborate braking system.（P5）用低能机器或传力工具，操作者通过向踏板或把手的一个简单机械连接构件作用足够的力量到车闸固定的部分。大多数情况，然而，用一个详细（复杂）的车闸系统使这个力量成倍增加。 2. The fundamental principle involved is the use of compressed air acting through a piston in a cylinder to set block brakes on the wheels. The action is simultaneous on the wheels of all the cars in the train. The compressed air is carried through a strong hose from car to car with couplings between cars; its release to all the separate block brake units, at the same time, is controlled by the engineer. (Braking Systems)（P5） 相关的基本原理是使用压缩气体，通过气缸内的活塞将闸块压在车轮起作用。列车的所有车厢上的车轮同时动作。压缩气体通过一个坚固的管道在由联轴器连接的车厢之间传输；工程师控制其在同一时间释放到所有独立的闸块单元。 3.When the brake pedal of an automobile is depressed, a force is applied to a piston in a master cylinder. The piston forces hydraulic fluid through metal tubing into a cylinder in each wheel where the fluid’s pressure moves two pistons that press the brake shoes against the drum. (Braking Systems)（P5） 当踩下汽车刹车的踏板，在主汽缸中的活塞上施加一个力。活塞驱动液压流体通过金属管道进入每个车轮气缸，在那里液压移动两个活塞将闸片压向轮圈。 4.Machinery ontology including mechanical rack, mechanical connections and mechanical transmission, which is the basis of mechanical-electrical integration, plays a role in supporting the other functional units of the system and transmitting motion and power. Compared to purely mechanical products, the performance and functionality of integration technology in electrical and mechanical systems have been improved a lot, which requires mechanical ontology to adapt its new status in mechanical structure, materials, processing technology, as well as the areas of geometry. Accordingly, the new ontology is with high efficient, multi-functional, reliable and energy-saving, small, light-weighted and aesthetically pleasing characteristics. (Mechatronics System) （P7） 机械体包括机架、机械联接和机械传动，它是机电一体化的基础，作用是支撑系统其他功能单元，传递运动和动力。和纯机械产品相比，一体化技术的性能和功能在机电系统中大幅提高，它要求机械本体适应在机械结构、材料、加工技术以及这些领域中的几何学下的新环境。相应的，新的一体化具有高效、多功能、可靠、节能、小轻和美学的令人赏心悦目的特征。 5. Detecting sensor detecting sensor part includes a variety of sensors and signal detection circuit, and its function is to detect the process of mechatronic systems in the work itself and the changes of relevant parameters in external environment and transmit the information to the electronic control unit. Electronic control unit check the information and sends the corresponding control issues to the actuator. (Mechatronics System) （P7） 检测传感器部分包括各类传感器、信号检测电路，它的功能是检测机电系统自身工作的工程，在外部环境下的相关参数的改变，将其信息传给电子控制单元。电子控制单元通过检查信息，送出相应的指令到执行机构。 6. Electronic control unit, also known as ECU, is the core of mechatronic systems, responsible for the external commands and the signals output by sensors. It centralizes stores, computes and analyzes the information. Based on the results of information processing,instruction are issued according to a certain extent and pace to control the destination for the entire system. (Mechatronics System) （P7） 电子控制单元，也被称为控制单元（ECU）控制，是机电系统的核心，负责外部命令和传
机械专业英语复试词汇总结
机械英语词汇大全2 金属切削 metal cutting 机床 machine tool 金属工艺学 technology of metals 刀具 cutter 摩擦 friction 联结 link 传动 drive/transmission 轴 shaft 弹性 elasticity 频率特性 frequency characteristic 误差 error 响应 response 定位 allocation 拉孔 broaching 装配 assembling 铸造 found 流体动力学 fluid dynamics 流体力学 fluid mechanics 加工 machining 液压 hydraulic pressure 切线 tangent 机电一体化 mechanotronics mechanical-electrical integration 气压 air pressure pneumatic pressure 稳定性 stability 介质 medium 数学模型 mathematical model 画法几何 descriptive geometry 机械制图 Mechanical drawing 投影 projection 视图 view 剖视图 profile chart 标准件 standard component 零件图 part drawing 装配图 assembly drawing 尺寸标注 size marking 技术要求 technical
机床夹具 jig 动力学 dynamic 运动学 kinematic 静力学 static 分析力学 analyse mechanics 拉伸 pulling 压缩 hitting 剪切 shear 扭转 twist 弯曲应力 bending stress 强度 intensity 三相交流电 three-phase AC 磁路 magnetic circles 变压器 transformer 异步电动机 asynchronous motor 液压驱动泵 fluid clutch 液压泵 hydraulic pump 阀门 valve 失效 invalidation 强度 intensity 载荷 load 应力 stress 安全系数 safty factor 可靠性 reliability 螺纹 thread 螺旋 helix 键 spline 销 pin 滚动轴承 rolling bearing 滑动轴承 sliding bearing requirements 刚度 rigidity 内力 internal force 位移 displacement 截面 section 疲劳极限 fatigue limit 断裂 fracture 塑性变形 plastic distortion 脆性材料 brittleness material 刚度准则 rigidity criterion 垫圈 washer 垫片 spacer 直齿圆柱齿轮
机械工程专业英语教程(第2版)[施平主编][翻译]_lesson19
Gear Materials (Reading Material) 齿轮材料（阅读材料） Gears are manufactured from a wide variety of materials, both metallic as well as nonmetallic. 齿轮由多种种类的材料制造，包括金属材料和非金属材料。 As is the case with all materials used in design, the material chosen for a particular gear should be the cheapest available that will ensure satisfactory performance. 在设计中可以使用多种材料的情况下，对于特定齿轮，应当做到选用满足使用要求下的最便宜的材料。Before a choice is made, the designer must decide which of several criteria is most important to the problem at hand. 在作出选择前，设计师必须决定在众多设计准则中哪个是当前最重要的。 If high strength is the prime consideration, a steel should usually be chosen rather than cast iron. 如果高强度是第一要考虑的因素，通常就选择钢材而不选择铸铁。 If wear resistance is the most important consideration, a can be made, for problems involving noise reduction, nonmetallic. Materials perform better than metallic ones. 如果耐磨性是最重要的因素，可以选用非金属材料要比金属材料更好，同时也可以解决降低噪声的问题。However, as is true in most design problems, the final choice of a material is usually a compromise. 然而，在大部分实际设计问题中，对材料的最终决定往往是一个折衷的方案。 In other words, the material chosen will conform reasonably well to all the requirements mentioned previously, although it will not necessarily be the best in any one area. 换句话说，材料的选择要考虑到合理的达到所有的预定要求，尽管这样就不能在其中任何一方面达到最好。To conclude this discussion we will consider the characteristics of various metallic and nonmetallic gear materials according to their general classifications. 为了总结这次讨论，我们将按照通常的分类来考虑多种金属和非金属齿轮材料所具有的特性。 Cast Irons 铸铁 Cast iron is one of the most commonly used gear materials. 铸铁是最常用的齿轮材料之一。 Its low cost, ease of casting, good machinability, high wear resistance, and good noise abatement property make it a logical choice. 它具有低成本，铸造性好，机械加工性能好，高耐磨性，以及高减噪性的特点，这些特点使铸铁成为一个合适的选择对象。 The primary disadvantage of cast iron as a gear material is its low tensile strength, which makes the gear tooth weak in bending and necessitates rather large teeth. 铸铁主要的缺点是，作为一种齿轮材料，铸铁的抗拉强度很低，这使得轮齿的抗弯强度很弱而且不能造出很大的轮齿。 Another type of cast iron is nodular iron, which is made of cast iron to which a material such as magnesium or cerium has been added. 另一种类型的铸铁是球墨铸铁，是在普通铸铁中加入了镁或者铈制成的。 The result of this alloying is a material having a much higher tensile strength while retaining the good wear and machining characteristics of ordinary cast iron. 这种合金的特点是既具有高的抗拉强度，又保持了普通铸铁的高耐磨性和优秀的机械加工性能。 V ery often the combination of cast iron gear and a steel pinion will give a well balanced design with regard to cost,