武科大机械行业管理专业英语Lesson39(PPT 43页).ppt

Lesson39GearManufacturingMethods TerminologyTexttour 09 03 2020 1 机械工程专业英语教程 Terminology 09 03 2020 2 机械工程专业英语教程 AnnularShapedlikeorformingaring 环形的 轮状的 形状像环或形成环状 Annulargear内齿轮 齿圈 也称为internalgear 机械工程专业英语教程 09 03 2020 Helicalgear斜齿轮 3 Hob滚刀 09 03 2020 机械工程专业英语教程 4 Worm蜗杆Wormgear1 Agearconsistingofaspirallythreadedshaftandawheelwithmarginalteeththatmeshintoit蜗轮蜗杆副2 Thetoothedwheelofthisgear awormwheel蜗轮 09 03 2020 机械工程专业英语教程 5 Broach拉刀SwarfFinemetallicfilingsorshavingsremovedbyacuttingtool 小铁屑 用锉或剃等加工方法去除的细小金属屑 09 03 2020 机械工程专业英语教程 6 DressingDressingistheprocessofconditioningworngrainsonthesurfaceofagrindingwheelbyproducingsharpnewedgesongrainssothattheycancutmoreefficiently 砂轮修整 使砂轮表面磨钝的磨粒上产生新的锋利的切削刃 使其能够更有效地进行切削工作 09 03 2020 机械工程专业英语教程 7 GearPlaning 刨齿 Theshapeofthespacebetweengearteethiscomplexandvarieswiththenumberofteethonthegearaswellastoothmodule 模数 somostgearmanufacturingmethodsgeneratethetoothflank 齿腹 insteadofforming 采用展成法加工齿面而不是采用成形法加工 机械工程专业英语教程 09 03 2020 Texttour 8 Gearplaningusesareciprocatingrack 往复运动的齿条刀 stroking 击 打 切 inthedirectionofthehelix 螺旋 onagearwithagradualgenerationofformastherackeffectivelyrollsroundthegearblank 齿轮毛坯 当齿条刀绕齿轮坯料滚切并沿其螺旋线方向运动时 齿形就会被逐渐展成 Therackisrelievedoutofcontact 脱离接触 forthereturnstrokeasinnormalshapingorplaning 与普通的刨削加工相同 Ithasthegreatadvantagethatthecuttingtoolisasimplerackwith nearly straightsidedteethwhichcaneasilybegroundaccurately 刀具为具有直线齿形或者接近与直线齿形的齿条 其齿面易于进行精确磨削加工 Thismethodislittleused 几乎不用 forhighproductionbecauseitisrelativelyslowinoperationduetothehightoolandslidemass 由于刀具和滑枕的质量较大 forjobbing 重复性很小的工作 purposestheslowstrokingratedoesnotmatterandlowtoolcostsgiveanadvantagewhereunusualsizesorprofilemodificationsarerequired 对于单件或者少量的齿轮加工而言 缓慢的行程速度带来的影响不大 而且较低的刀具成本对于那些特殊规格和需要进行齿廓修形的齿轮来说则是一个有利的条件 GearShaping 插齿 Gearshapingisinherentlysimilartogearplaning 刨齿加工 butusesacircularcutter 圆形刀具 insteadofarack 齿条刀 andtheresultingreductioninthereciprocatinginertia 运动惯性 allowsmuchhigherstrokingspeeds 行程速度 moderngearshapers 插齿机 cuttingcargearscanrunat2000cuttingstrokesperminute Theshapeofthecutterisroughlythesameasaninvolutegear 渐开线齿轮 butthetipsoftheteetharerounded Thegeneratingdrivebetweencutterandworkpiecedoesnotinvolvearackorleadscrewsinceonlycircularmotionisinvolved 由于刀具与工件之间的展成运动只包含圆周运动 因此不需要齿条或者丝杠 Thetoolandworkpiecemovetangentially 切向移动 typically0 5mmforeachstrokeofthecutter Onthereturnstrokethecuttermustberetracted 退让 about1mmtogiveclearanceotherwisetoolruboccursonthebackstroke 退刀 andfailureisrapid Theadvantagesofgearshapingarethatproductionratesarerelativelyhighandthatitispossibletocutrightuptoashoulder 将齿插到接近轴肩处 Unfortunately forhelicalgears 斜齿轮 ahelicalguide 螺旋导轨 isrequiredtoimposearotationalmotiononthestrokingmotion 需要有一个能够产生绕插齿运动行程本身旋转的螺旋导轨 suchhelicalguidescannotbeproducedeasilyorcheaplysothemethodisonlysuitableforlongrunswithhelicalgears 斜齿轮的大批量加工 sincespecialcuttersandguidesmustbemanufacturedforeachdifferenthelixangle Agreatadvantageofgearshapingisitsabilitytocutannular 环形的 轮状的 gearssuchasthoserequiredforlargeepicyclicdrives 行星齿轮传动 GearHobbing 滚齿 Gearhobbing themostusedmetalcuttingmethod usestherackgeneratingprinciple 齿条展成原理 butavoidsslowreciprocationbymountingmany racks onarotatingcutter 旋转刀具 The racks aredisplacedaxiallytoformagashed 很深的裂缝 worm 这些 齿条 轴向排布 形成了有缝的蜗杆 Metalremovalratesarehighsincenoreciprocationofhoborworkpiece 滚刀和工件 isrequiredandsocuttingspeedsof40m mincanbeusedforconventionalhobs 普通滚刀 andupto150m minforcarbidehobs 硬质合金滚刀 Typicallywitha100mmdiameterhobtherotationspeedwillbe100rpmandsoatwentytoothworkpiecewillrotateat5rpm Eachrevolutionoftheworkpiecewillcorrespondto0 75mmfeedsothehobwilladvancethroughtheworkpieceatabout4mmperminute Forcarproductionroughingmultiplestarthobs 多头粗加工滚刀 canbeusedwithcoarsefeedsof3mmperrevolutionsothat100rpmonthecutter atwo starthob 双头滚刀 anda20toothgearwillgiveafeedrateof30mm min GearBroaching 拉齿 Gearbroachingisnotusuallyusedforhelicalgears 斜齿轮 butisusefulforinternalspurgears 直齿轮 theprincipleuseofbroachinginthiscontext 在这种情况下 isforinternalsplines 内花键 whichcannoteasilybemadebyanyothermethod Aswithallbroachingthemethodisonlyeconomicforlargequantitiessincesetupcosts 设备的费用 arehigh GearBroachinggiveshighaccuracyandlowsurfaceroughness 低表面粗糙度 butlikeallcuttingprocessesislimitedto soft materialswhichmustbesubsequently 随后 case hardenedorheattreated 表面硬化或者热处理 givingdistortion 产生变形 GearShaving 剃齿 Gearshavingisusedasfinishingprocessesforgearsinthe soft state Theobjectiveistoimprovesurfaceroughnessandprofile 降低齿面粗糙度和改善齿廓形状 bymatingtheroughed outgearwitha cutter whichwillimproveform 通过采用具有较高齿形精度的 刀具 与经过粗加工的齿轮进行啮合 Agearshavingcutterlookslikeagearwhichhasextraclearance 附加的凹槽 attheroot forswarfandcoolantremoval细铁屑冷却液排除 andwhosetoothflankshavebeengrooved 开小槽 togivecuttingedges 形成切削刃 Itisruninmeshwiththeroughgearwithcrossedaxes 剃齿刀与经过粗加工的齿轮成交错轴啮合传动 sothatthereisintheorypointcontact 点接触 witharelativevelocityalongtheteeth 沿轮齿 givingscrapingaction 刮削作用 Thegearshavingcutterteetharerelativelyflexibleinbendingandsowillonlyoperateeffectivelywhentheyareindoublecontactbetweentwogearteeth 剃齿刀的刀齿具有相当的弯曲柔性 因此 只有当它们在两个轮齿之间并且与这两个轮齿都接触时 才能有效地进行切削工作 Thegearandcutteroperateathighrotationalspeedswithtraversing 通过 穿过 oftheworkfaceandabout100micronofmaterialisremoved Cycletimes 周期时间 canbelessthanhalfaminuteandthemachinesarenotexpensivebutcutteraredelicate 精密 anddifficulttomanufacture GearGrinding 磨齿 Geargrindingisextremelyimportantbecauseitisthemainwayhardenedgears 淬硬齿轮 aremachined Whenhighaccuracyisrequireditisnotsufficienttopre correct 预先校正 forheattreatmentdistortionandgrindingisthennecessary Thesimplestapproachtogeargrindingisformgrinding 成形磨削法 Thewheelprofileisdressed 修整 accuratelytoshapeusingsinglepointdiamondswhicharecontrolledbytemplatescuttotheexactshaperequired 采用由精密切削成形的样板控制的单刃金刚石可以将砂轮修整成精确的形状 Theprofiledwheelisthenreciprocated 往返进给 axiallyalongthegear 沿轴向 whenonetoothshapehasbeenfinished involvingtypically100micronmetalremoval thegearisindexedto 索引 分度到 thenexttoothspace Thismethodisfairlyslowbutgiveshighaccuracyconsistently Settingupislengthybecausedifferentdressingtemplates 砂轮修整样板 areneededifmodule numberofteeth helixangle orprofilecorrection 齿廓修形量 arechanged Thefastestgeargrindingmethodusesthesameprincipleasgearhobbing 滚齿 butreplacesagashedandrelievedworm 有排屑槽的蜗杆形滚齿刀 byagrindingwheelwhichisarackinsection