外文翻译-机械设计.doc

1、毕 业 设 计（论 文）外 文 参 考 资 料 及 译 文译文题目： Mechanical Design 机 械 设 计 学生姓名： 学 号： 专 业： 所在学院： 指导教师： 职 称： 20xx年 2月 27日Mechanical DesignJohn ErnstAbstractA machine is a combination of mechanisms and other components which transforms transmits. Examples are engines, turbines, vehicles, hoists, printing presses, w

2、ashing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term mechanical design is used in a broader sense than machine design to include their design. The motion and structural aspects

3、 and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers. Keywords: Mechani

4、cal Design；Mechanisms Design Process；Application1. The Design Progress Designing starts with a need real. Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previously.Done by men, such as computation, assembl

5、y, or servicing. With the objective wholly or partly.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 design early time, namely in front of the plan blueprint is

6、corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, and then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.

7、When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive cost. Optimum proportions and dimensio

8、ns will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen.Theseimportantobjectivescanbeattainedonlybyanalysisbasedupontheprinciplesofmechanics,suchasthoseofstaticforreactionforcesandfort

9、heoptimumutilizationoffriction;ofdynamicsforinertia,acceleration,andenergy;ofelasticityandstrengthofmaterialsforstressanddeflection;ofphysicalbehaviorofmaterials;andoffluidmechanicsforlubricationandhydrodynamicdrives.Theanalysesmaybemadebythesameengineerwhoconceivedthearrangementofmechanisms,or,inal

10、argecompany,theymaybemadebyaseparateanalysisdivisionorresearchgroup.Designisareiterativeandcooperativeprocess,whetherdoneformallyorinformally,andtheanalystcancontributetophasesotherthanhisown.Productdesignrequiresmuchresearchanddevelopment.ManyConceptsofanideamustbestudied,tried,andtheneitherusedord

11、iscarded.Althoughthecontentofeachengineeringproblemisunique,thedesignersfollowthesimilarprocesstosolvetheproblems.Productliabilitysuitsdesignersandforcedinmaterialselection,usingthebestprogram.Intheprocessofmaterial,themostcommonproblemsforfive(a)dontunderstandornotuseaboutthelatestapplicationmateri

12、alstothebestinformation,(b)failedtoforeseeandconsiderthereasonableusematerialmay(suchaspossible,designersshouldfurtherforecastandconsiderduetoimproperuseproducts.Inrecentyears,manyproductsliabilityinlitigation,theuseofproductsandhurttheplaintiffaccusedmanufacturer,andwonthedecision),(c)ofthematerial

13、susedallorsomeofthedata,data,especiallywhentheuncertaintylong-termperformancedataisso,(d)qualitycontrolmethodisnotsuitableandunproven,(e)bysomecompletelyincompetentpersonschoosematerials.Throughtotheabovefivequestionsanalysis,mayobtainthesequestionsisdoesnothavethesufficientreasonexistencetheconclus

14、ion.Mayforavoidthesequestionstothesequestionsresearchanalysestheappearanceindicatingthedirection.Althoughusesthebestchoiceofmaterialmethodnottobeabletoavoidhavingtheproductresponsibilitylawsuit,designsthepersonnelandtheindustrycarriesonthechoiceofmaterialaccordingtothesuitableprocedure,maygreatlyreducethelawsuitthequantity.Mayseefromtheabovediscussion,thechoicematerialpeopleshouldtothematerialnature,thecharacteristicandtheprocess