机械工程专业英语课件--L11

EnglishforMechanicalEngineering机械工程专业英语常州工学院机电工程学院徐红丽机械工程专业英语预备知识一、预备知识Lesson23FundamentalsofMachineTools机床的主要部件：床身：是基础件，一般为铸件，有较高的抗压强度，吸振导轨和溜板箱：保证机床部件的直线运动，其精度极高，一般为内凹，为了储油。主轴和轴承：回转精度要求较高，径向跳动、轴向窜动和角度摆动变速机构：实现刀具相对工件的正确切削用量。机械、液压、气动、电动动力装置：电动机词汇二、词汇机械工程专业英语machinetool机床bed床身slideway导轨spindle主轴tailstock尾座dovetail燕尾槽gib镶条guard防罩roughing粗加工finishing精加工surfacefinish表面光洁度Lesson23FundamentalsofMachineTools机械工程专业英语Inmanycasesproductsfromtheprimaryformingprocessesmustundergofurtherrefinementsinsizeandsurfacefinishtomeettheirdesignspecifications.Tomeetsuchprecisetolerancestheremovalofsmallamountsofmaterialisneeded.Usuallymachinetoolsareusedforsuchoperation.课文分析Lesson23FundamentalsofMachineTools三、课文分析机械工程专业英语Inmanycasesproductsfromtheprimaryformingprocessesmustundergofurtherrefinementsinsizeandsurfacefinishtomeettheirdesignspecifications.课文分析许多情况下，经初步成形加工出来的工件必须在尺寸和表面光洁度方面进一步精加工整，以满足它们的设计要求。[ri‘fainmənt]n.精[提]炼,精制;净化;精美清扫[除,洗]高尚,优雅精致,精细,精确Lesson23FundamentalsofMachineTools机械工程专业英语Tomeetsuchprecisetolerancestheremovalofsmallamountsofmaterialisneeded.Usuallymachinetoolsareusedforsuchoperation.课文分析为了满足精密的公差要求，需要从工件上去掉小量材料。通常机床就是用于实现这种加工的设备。[pri’sais]adj.精确的,明确的;清晰的,恰好的;正当,严格的;拘泥的,陈规的Lesson23FundamentalsofMachineTools机械工程专业英语IntheUnitedStatesmaterialremovalisabigbusiness—inexcessof$36×109peryear,includingmaterial,labor,overhead,andmachine-toolshipments,isspent.Since60percentofthemechanicalandindustrialengineeringandtechnologygraduateshavesomethingconnectionwiththemachiningindustryeitherthroughsale,design,oroperationofmachineshops,orworkinginrelatedindustry,itiswiseforanengineeringstudenttodevotesometimeinhiscurriculumtostudyingmaterialremovalandmachinetools.课文分析Lesson23FundamentalsofMachineTools机械工程专业英语IntheUnitedStatesmaterialremovalisabigbusiness—inexcessof$36×109peryear,includingmaterial,labor,overhead,andmachine-toolshipments,isspent.课文分析在美国，材料切削业是一个很大的行业---费用每年超过36×109美元，包括材料，劳动力，杂项开支，机床运输费等所花的费用。[’əuvəhed]n.经常开支,普通费用天花板;船舱的顶板Lesson23FundamentalsofMachineTools机械工程专业英语Since60percentofthemechanicalandindustrialengineeringandtechnologygraduateshavesomethingconnectionwiththemachiningindustryeitherthroughsale,design,oroperationofmachineshops,orworkinginrelatedindustry,itiswiseforanengineeringstudenttodevotesometimeinhiscurriculumtostudyingmaterialremovalandmachinetools.课文分析由于60％机械和工业技术工程专业的毕业生做销售、设计、管理机械工厂、或在相关领域工作，总要和加工工业打交道，因此，对于工程专业学生来说，在他的学习计划中安排一段时间去学习研究材料切削和机床，是非常明智的。[’grædjuit]n.毕业生,得学位者Lesson23FundamentalsofMachineTools机械工程专业英语Amachinetoolprovidesthemeansforcuttingtoolstoshapeaworkpiecetorequireddimensions;课文分析Lesson23FundamentalsofMachineToolsthemachinesupportsthetoolandtheworkpieceinacontrolledrelationshipthroughthefunctioningofitsbasicmembers,whichareasfollows:机床通过使用切削刀具使工件成形以达到所要求的尺寸。机床通过其基础构件的作用，支承相互联系的刀具和工件，现将基本部件列举如下：机械工程专业英语(a)Bed,Structureorframe.Thisisthemainmemberwhichprovidesabasisfor,andaconnectionbetween,thespindlesandslides;thedistortionandvibrationunderloadmustbekepttoaminimum.课文分析Lesson23FundamentalsofMachineTools这是一个主要部件，该部件为主轴、拖板箱等提供一个基础支撑和中间连接，在负载作用下，它必须能使变形和振动保持最小。机械工程专业英语SlidesandSlideways.Thetranslationofamachineelement(e.g.theslide)isnormallyachievedbystraight-linemotionundertheconstraintofaccurateguidingsurfaces(theslideway).课文分析Lesson23FundamentalsofMachineTools拖板箱和导轨。机床部件（如拖板箱）的移动，通常是在精密的导轨面约束下靠直线运动来实现。机械工程专业英语(c)SpindlesandBearings.Angulardisplacementstakeplaceaboutanaxisofrotation;thepositionofthisaxismustbeconstantwithinextremelyfinelimitsinmachinetools,andisensuredbytheprovisionofprecisionspindlesandbearings.课文分析Lesson23FundamentalsofMachineTools主轴和轴承。角位移是绕一根旋转轴线产生的，在机床中该轴线的位置必须在极其精确的范围内保持不变，是靠高精度的主轴及其轴承来保证。机械工程专业英语(d)PowerUnit.Theelectricmotoristheuniversallyadoptedpowerunitformachinetools.Bysuitablypositioningindividualmotors,beltandgeartransmissionsarereducedtoaminimum.课文分析Lesson23FundamentalsofMachineTools动力装置。电动机是机床中普遍采用的动力装置。通过对各个电机的合适定位，使皮带和齿轮传动装置减少到最小。机械工程专业英语(e)TransmissionLinkage.Linkageisthegeneraltermusedtodenotethemechanical,hydraulic,pneumaticorelectricmechanismswhichconnectangularandlineardisplacementsindefinedrelationship.课文分析Lesson23FundamentalsofMachineTools变速机构。变速机构是个通用术语，用来代表机械、液压、气动或电动变速机构的，变速机构保证角位移和线性位移的确定传动比。机械工程专业英语Therearetwobroaddivisionsofmachiningoperations:课文分析Lesson23FundamentalsofMachineTools机械加工有两个主要的组成部分：(a)Roughing,forwhichthemetalremovalrate,andconsequentlythecuttingforce,ishigh,buttherequireddimensionalaccuracyrelativelylow.粗加工。在粗加工中，金属切除率高，因而往往切削力也大，但所要求的尺寸精度较低。机械工程专业英语(b)Finishing,forwhichthemetalremovalrate,andconsequentlythecuttingforce,islow,buttherequireddimensionalaccuracyrelativelyhigh.课文分析Lesson23FundamentalsofMachineTools精加工。精加工时，金属切除率低，因而相应的切削力也小，但所要求的尺寸精度和表面光洁度较高。机械工程专业英语Itfollowsthatstaticloadsanddynamicloads,suchasresultfromanunbalancedgrindingwheel,aremoresignificantinfinishingoperationsthaninroughingoperations.Thedegreeofprecisionachievedinanymachiningprocesswillusuallybeinfluencedbythemagnitudeofthedeflections,whichoccurasaresultoftheforceacting.课文分析Lesson23FundamentalsofMachineTools机械工程专业英语Itfollowsthatstaticloadsanddynami