机械设计外文翻译(中英文)学习资料

机械设计理论

机械设计是一门通过设计新产品或者改进老产品来满足人类需求的应用技术科学。它涉及工程技术的各个领域，主要研究产品的尺寸、形状和详细结构的基本构思，还要研究产品在制造、销售和使用等方面的问题。

进行各种机械设计工作的人员通常被称为设计人员或者机械设计工程师。机械设

计是一项创造性的工作。设计工程师不仅在工作上要有创造性，还必须在机械制图、运动学、工程材料、材料力学和机械制造工艺学等方面具有深厚的基础知识。如前所诉，机械设计的目的是生产能够满足人类需求的产品。发明、发现和科技

知识本身并不一定能给人类带来好处，只有当它们被应用在产品上才能产生效益。因而，应该认识到在一个特定的产品进行设计之前，必须先确定人们是否需要这种产品。应当把机械设计看成是机械设计人员运用创造性的才能进行产品设计、系统分析

和制定产品的制造工艺学的一个良机。掌握工程基础知识要比熟记一些数据和公式更为重要。仅仅使用数据和公式是不足以在一个好的设计中做出所需的全部决定的。另一方面，应该认真精确的进行所有运算。例如，即使将一个小数点的位置放错，也会使正确的设计变成错误的。

一个好的设计人员应该勇于提出新的想法，而且愿意承担一定的风险，当新的方法不适用时，就使用原来的方法。因此，设计人员必须要有耐心，因为所花费

的时间和努力并不能保证带来成功。一个全新的设计，要求屏弃许多陈旧的，为人们所熟知的方法。由于许多人墨守成规，这样做并不是一件容易的事。一位机械设计师应该不断地探索改进现有的产品的方法，在此过程中应该认真选择原有的、经过验证的设计原理，将其与未经过验证的新观念结合起来。

新设计本身会有许多缺陷和未能预料的问题发生，只有当这些缺陷和问题被解决之后，才能体现出新产品的优越性。因此，一个性能优越的产品诞生的同时，也伴随着较高的风险。应该强调的是，如果设计本身不要求采用全新的方法，就没有必要仅仅为了变革的目的而采用新方法。

在设计的初始阶段，应该允许设计人员充分发挥创造性，不受各种约束。即使产生了许多不切实际的想法，也会在设计的早期，即绘制图纸之前被改正掉。只有这样，才不致于堵塞创新的思路。通常，要提出几套设计方案，然后加以比较。

很有可能在最后选定的方案中，采用了某些未被接受的方案中的一些想法。

心理学家经常谈论如何使人们适应他们所操作的机器。设计人员的基本职责是努力使机器来适应人们。这并不是一项容易的工作，因为实际上并不存在着一个对所有人来说都是最优的操作范围和操作过程。

另一个重要问题，设计工程师必须能够同其他有关人员进行交流和磋商。在开始阶段，设计人员必须就初步设计同管理人员进行交流和磋商，并得到批准。这一般是通过口头讨论，草图和文字材料进行的。为了进行有效的交流，需要解决下列问题：

（1）所设计的这个产品是否真正为人们所需要？

（2）此产品与其他公司的现有同类产品相比有无竞争能力？

（3）生产这种产品是否经济？

（4）产品的维修是否方便？

（5）产品有无销路？是否可以盈利？

只有时间能对上述问题给出正确答案。但是，产品的设计、制造和销售只能在对上述问题的初步肯定答案的基础上进行。设计工程师还应该通过零件图和装配图，与制造部门一起对最终设计方案进行磋商。

通常，在制造过程中会出现某个问题。可能会要求对某个零件尺寸或公差作一些更改，使零件的生产变得容易。但是，工程上的更改必须要经过设计人员批准，以保证不会损伤产品的功能。有时，在产品的装配时或者装箱外运前的试验中才发现设计中的某种缺陷。这些事例恰好说明了设计是一个动态过程。总是存在着更好的方法来完成设计工作，设计人员应该不断努力，寻找这些更好的方法。

近些年来，工程材料的选择已经显得重要。此外，选择过程应该是一个对材料的连续不断的重新评价过程。新材料不断出现，而一些原有的材料的能够获得的数量可能会减少。环境污染、材料的回收利用、工人的健康及安全等方面经常会对材料选择附加新的限制条件。为了减轻重量或者节约能源，可能会要求使用不同的材料。来自国内和国际竞争、对产品维修保养方便性要求的提高和顾客的反馈等方面的压力，都会促使人们对材料进行重新评价。由于材料选用不当造成的产品责任诉讼，已经产生了深刻的影响。此外，材料与材料加工之间的相互依赖关系已经被人们认识得更清楚。因此，为了能在合理的成本和确保质量的前提下获得满意的结果，设计工程师的制造工程师都必须认真仔细地选择、确定和使用材料。

制造任何产品的第一步工作都是设计。设计通常可以分为几个明确的阶段：（a）

初步设计；（b）功能设计；（c）生产设计。在初步设计阶段，设计者着重考虑产品应该具有的功能。通常要设想和考虑几个方案，然后决定这种思想是否可行；如果可行，则应该对其中一个或几个方案作进一步的改进。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择；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。

在功能设计和工程设计阶段，要做出一个切实可行的设计。在这个阶段要绘制出相当完整的图纸，选择并确定各种零件的材料。通常要制造出样机或者实物模型，并对其进行试验，评价产品的功能、可靠性、外观和维修保养性等。虽然这种试验可能会表明，在产品进入到生产阶段之前，应该更换某些材料，但是，绝对不能将这一点作为不认真选择材料的借口。应该结合产品的功能，认真仔细地考虑产品的外观、成本和可靠性。一个很有成就的公司在制造所有的样机时，所选用的材料应该和其生产中使用的材料相同，并尽可能使用同样的制造技术。这样对公司是很有好处的。功能完备的样机如果不能根据预期的销售量经济地制造出来，或者是样机与正式生产的装置在质量和可靠性方面有很大不同，则这种样机

就没有多大的价值。设计工程师最好能在这一阶段完全完成材料的分析、选择和确定工作，而不是将其留到生产设计阶段去做。因为，在生产设计阶段材料的更换是由其他人进行的，这些人对产品的所有功能的了解不如设计工程师。

在生产设计阶段中，与材料有关的主要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地进行加工，而且材料的数量能够比较容易保证供应。

在制造过程中，不可避免地会出现对使用中的材料做一些更改的情况。经验表明，可采用某些便宜材料作为替代品。然而，在大多数情况下，在进行生产以后改换材料要比在开始生产前改换材料所花费的代价要高。在设计阶段做好材料选择工作，可以避免多数这样的情况。在生产制造开始后出现了可供使用的新材料是更换材料的最常见的原因。当然，这些新材料可能降低成本、改进产品的性能。但是，必须对新材料进行认真的评价，以确保其所有性能都满足要求。应当记住，新材料的性能和可靠性很少像现有材料那样为人们所了解。大部分的产品失效和产品责任事故案件是由于在选用新材料作为替代材料之前，没有真正了解它们的

长期使用性能而引起的。

产品的责任诉讼迫使设计人员和公司在选择材料时，采用最好的程序。在材料过程中，五个最常见的问题为：（a）不了解或者不会使用关于材料应用方面的最新最好的信息资料；（b）未能预见和考虑擦黑年品可能的合理用途（如有可能，设计人员还应进一步

预测和考虑由于产品使用方法不当造成的后果。在近年来的

许多产品责任诉讼案件中，由于错误地使用产品而受到伤害的原告控告生产厂家，并且赢得判决）；（c）所使用的材料的数据不全或是有些数据不确定，尤其是当其长期性能数据是如此的时候；（d）质量控制方法不适当和未经验证；（e）由一些完全不称职的人员选择材料。

通过对上述五个问题的分析，可以得出这些问题是没有充分理由存在的结论。对

这些问题的研究分析可以为避免这些问题的出现指明方向。尽管采用最好的材料

选择方法也不能避免发生产品责任诉讼，设计人员和工业界按照适当的程序进行材料选择，可以大大减少诉讼的数量。

从以上的讨论可以看出，选择材料的人们应该对材料的性质，特点和加工方法有一个全面而基本的了解。

Machine design theory

The mach ine desig n is through desig ns the new product or improves the old product to meet the human need the application technical scienee. It invoIves the project tech no logy each doma in, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the pers onnel which in aspect the and so on manu facture, sale and use questi on.

Carries on each kind of mach ine desig n work to be usually called desig ns the personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mecha ni cal draw ing, kin ematics, engin eerig material, materials mecha nics and mach ine manu facture tech no logy has the deep eleme ntary kno wledge.

If front sues, the mach ine desig n goal is the producti on can meet the huma n n eed the product. The invention, the discovery and technical knowledge itself certainly not n ecessarily can bring the adva ntage to the huma nity, only has whe n they are applied can produce on the product the ben efit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product

Must regard as the mach ine desig n is the machi ne desig n pers onnel carries on using creative ability the product design, the system analysis and a formulation product manu facture tech no logy good opport uni ty. Grasps the project eleme ntary kno wledge to have to memorize some data and the formula is more importa nt tha n. The merely service data and the formula is insufficient to the completely decision which makes in a good desig n n eeds. On the other hand, should be earn est precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct desig n to turn wron gly.

A good design personnel should dare to propose the new idea, moreover is willing to un dertake the certa in risk, whe n the new method is not suitable, use orig inal method. Therefore, desig ns the pers onnel to have to have to have the patie nee, because spe nds the time and the endeavor certainly cannot guarantee brings successfully. A brand-new desig n, the request scree n aba ndons obsoletely many, knows very well the method for the people. Because many pers on of con servative ness, does this certa inly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the con firmati on new idea.

Newly desig ns itself can have the questi on occurre nee which many flaws and has not been able to expect, only has after these flaws and the question are solved, can man ifest new goods come in to the market the product superiority. Therefore, a performa nee superior product is born at the same time, also is follow ing a higher risk. Should emphasize, if desig ns itself does not request to use the brand-new method, is not unn ecessary merely for the goal which tran sform to use the new method.

In the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the desig n early time, n amely in front of the pla n bluepri nt is corrected. Only then, only the n does not send to stops up the inno vati on the men tality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the pla n which fin ally desig nated,has used certa in not in pla n some ideas which accepts.

冲压模具技术外文翻译(含外文文献)

前言 在目前激烈的市场竞争中，产品投入市场的迟早往往是成败的关键。模具是高质量、高效率的产品生产工具，模具开发周期占整个产品开发周期的主要部分。因此客户对模具开发周期要求越来越短，不少客户把模具的交货期放在第一位置，然后才是质量和价格。因此，如何在保证质量、控制成本的前提下加工模具是值得认真考虑的问题。模具加工工艺是一项先进的制造工艺，已成为重要发展方向，在航空航天、汽车、机械等各行业得到越来越广泛的应用。模具加工技术，可以提高制造业的综合效益和竞争力。研究和建立模具工艺数据库，为生产企业提供迫切需要的高速切削加工数据，对推广高速切削加工技术具有非常重要的意义。本文的主要目标就是构建一个冲压模具工艺过程，将模具制造企业在实际生产中结合刀具、工件、机床与企业自身的实际情况积累得高速切削加工实例、工艺参数和经验等数据有选择地存储到高速切削数据库中，不但可以节省大量的人力、物力、财力，而且可以指导高速加工生产实践，达到提高加工效率，降低刀具费用，获得更高的经济效益。 1.冲压的概念、特点及应用 冲压是利用安装在冲压设备（主要是压力机）上的模具对材料施加压力，使其产生分离或塑性变形，从而获得所需零件（俗称冲压或冲压件）的一种压力加工方法。冲压通常是在常温下对材料进行冷变形加工，且主要采用板料来加工成所需零件，所以也叫冷冲压或板料冲压。冲压是材料压力加工或塑性加工的主要方法之一，隶属于材料成型工程术。 冲压所使用的模具称为冲压模具，简称冲模。冲模是将材料（金属或非金属）批量加工成所需冲件的专用工具。冲模在冲压中至关重要，没有符合要求的冲模，批量冲压生产就难以进行；没有先进的冲模，先进的冲压工艺就无法实现。冲压工艺与模具、冲压设备和冲压材料构成冲压加工的三要素，只有它们相互结合才能得出冲压件。 与机械加工及塑性加工的其它方法相比，冲压加工无论在技术方面还是经济方面都具有许多独特的优点，主要表现如下； (1) 冲压加工的生产效率高，且操作方便，易于实现机械化与自动化。这是

机械手机械设计论文中英文资料对照外文翻译

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外文翻译

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河南科技学院新科学院 2013届本科毕业生论文（设计） 英文文献及翻译 Foreign capital inflows and welfare in an economy with imperfect competition 学生姓名：王艳杰 所在院系：经济系 所学专业：国际经济与贸易 导师姓名：侯黎杰 完成时间：2013年4月15日

Foreign capital inflows and welfare in an economy with imperfect competition Abstract:This paper examines the resource allocational and welfare effects of exogenous inflows of foreign capital in a general-equilibrium model with oligopolistic competition and unemployment. Although the welfare impact for the short run is ambiguous and dependent upon the strength of excess profits and scale economies relative to unemployment in manufacturing, in the long run additional inflows of foreign capital always improve national welfare with capital mobility. Hence, attracting foreign capital remains a sound policy for economies characterized by imperfect competition, scale economies,and regional unemployment. Keywords: International capital mobility; Imperfect competition; Welfare 1.Introduction The welfare effects of exogenous inflows of foreign capital in the presence of trade restrictions have been extensively studied. Brecher and Diaz Alejandro (1977) show that when imports are subject to tariffs, an introduction of fo reign capital inflows accentuates the tariff distortion and hence reduces national welfare if the import-competing sector is relatively capital-intensive. In contrast, Dei (1985) shows that when imports are restricted by quotas,foreign capital inflows in the presence of foreign-owned capital always improve welfare by depressing the rental and so lowering the payments to existing foreign-owned capital. Recently, Neary (1981), using a common framework for both tariffs and quotas, obtains more general results of foreign capital inflows; the welfare effect of such inflows depends crucially on whether foreign-owned capital exists initially in the home country. In addition, Khan (1982) and Grinols (1991) have examined the effects of foreign capital inflows for a generalized Harris-Todaro economy under tariff protection. Khan finds that the result by Brecher and Diaz Alejandro is still valid even in the presence of unemployment, whereas Grinols argues that increased foreign capital need not be detrimental to welfare if the opportunity costs of labor are sufficiently low. Noteworthy is that the models used by these authors are all based upon the premise of perfect competition along with constant returns-to-scale technology. Although perfect competition serves as a useful assumption in crystallizing theoretical insights, it nevertheless fails to depict many of the real-world phenomena. The real-world economy is characterized, to a large extent, by imperfect competition and economies of scale. The policy implications of imperfect competition and economies

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沈阳工业大学工程学院 毕业设计（论文）外文翻译 毕业设计（论文）题目：工具盒盖注塑模具设计 外文题目：Friction , Lubrication of Bearing 译文题目：轴承的摩擦与润滑 系（部）：机械系 专业班级：机械设计制造及其自动化0801 学生姓名：王宝帅 指导教师：魏晓波 2010年10 月15 日

外文文献原文： Friction , Lubrication of Bearing In many of the problem thus far , the student has been asked to disregard or neglect friction . Actually , friction is present to some degree whenever two parts are in contact and move on each other. The term friction refers to the resistance of two or more parts to movement. Friction is harmful or valuable depending upon where it occurs. friction is necessary for fastening devices such as screws and rivets which depend upon friction to hold the fastener and the parts together. Belt drivers, brakes, and tires are additional applications where friction is necessary. The friction of moving parts in a machine is harmful because it reduces the mechanical advantage of the device. The heat produced by friction is lost energy because no work takes place. Also , greater power is required to overcome the increased friction. Heat is destructive in that it causes expansion. Expansion may cause a bearing or sliding surface to fit tighter. If a great enough pressure builds up because made from low temperature materials may melt. There are three types of friction which must be overcome in moving parts: (1)starting, (2)sliding, and(3)rolling. Starting friction is the friction between two solids that tend to resist movement. When two parts are at a state of rest, the surface irregularities of both parts tend to interlock and form a wedging action. To produce motion in these parts, the wedge-shaped peaks and valleys of the stationary surfaces must be made to slide out and over each other. The rougher the two surfaces, the greater is starting friction resulting from their movement . Since there is usually no fixed pattern between the peaks and valleys of two mating parts, the irregularities do not interlock once the parts are in motion but slide over each other. The friction of the two surfaces is known as sliding friction. As shown in figure ,starting friction is always greater than sliding friction . Rolling friction occurs when roller devces are subjected to tremendous stress which cause the parts to change shape or deform. Under these conditions, the material in front of a roller tends to pile up and forces the object to roll slightly uphill. This changing of shape , known as deformation, causes a movement of molecules. As a result ,heat is produced from the added energy required to keep the parts turning and overcome friction. The friction caused by the wedging action of surface irregularities can be overcome