DIN-58405-2-1972-ENG

~DC621.833:681:621.753.1/.2DEUTSCHENORMEN.May1972Ii-cc0O0-QmC-.--mC3cooornon.-OEcC(3c1-EL.-5o?,Pi-5U2PSpurGearDrivesforPineHechanicsGearFitSelection,Tolerances,AllowancesDINI58405Sheet2StirnradgetriebederFeinwerktechnik;Getriebepassungsauswahl,Toleranzen,AbmaBeThereferencestotheotherSheetsofthisStandardrelatetotheMay1972issues.I.Gearfitselection1.1.DirectionsforselectingagearfitTheinitialdatadeterminingtheselectionofagearfitaretherequirementstobemetbythegeardriveregardingtorsionalbacklash(true-angletransmissionwithreversalofrotation)andcircumferentialspeed.Pordifferentfieldsofapplicationinvolvingfinemechanics,seeDIN58405Sheet1Section4,TableI,column1specifiesarangeofgearfitscorrelatedwithtorsionalbacklashandcircum-ferentialspeed.GearfitsnotlistedinthisTableshouldbespecifiedonlyinexceptionalcircumstances.Forfinemechanicsinparticular,dependingontheclassoffitandthetorsionalbacklashcon-cerned,thegearfitselectedrequirestheobservanceofgivenfinishesandtolerancesonthecriticalfeaturesofthegeardrivecomponents,namelythegear,theshaft,bearingsandhousing.Recommendationforthispurposeiagivenincolumn4to20inTable1.Inviewofthefactorsinvolved,thecorrectchoiceoffitisoftenextremelydifficultandthereforethedetailsinTableIshouldberegardedonlyasgeneraldirectionscoveringthefinishandt0leranChgoftheindividualgeardrivecomponents.Theyareintendedtoservethedesignerasachecklistofallthepointswhichmustbetakenintoaccountwhenchoosingagearfit.ApartfromthefinishesandtolerancesinTable1,thefollowingrequirementsmustalsobemetforallthegearfits:a)ThegearsmustliewithinthescopeofDIN58405Sheet1Section2.b)Whenthegearshaftiscarriedinballbearings,theoutsidediameterofthebearingshould............................----------1:2--beoeral,l-s~iremeoqB-oor-a_gear-oi4notexceed40timesthemodulewhenm=0.2toImm,or50timesthemodulewhenmismorethan1andnotmorethan3mm.Whenthegearshaftiscarriedinplainbearingstheshaftdiametershouldnotexceed8timesthemodule.c)TheIS0tolerancezonefortheballbearingseatinginthehousingandontheshaftshouldbechosenaccordingtoDIN5425tosuittheclassofgearfit(seeTable1).Inthecaseofhousingsmadeofaluminiumalloysandsimilarmaterials,suitablemeasuesshouldbetaken,e.g.dieburnishing,tocompactthesurfaceofthebearingboreandhencetoenlargetheload-bearingarea.thetotalbearingclearanceissmallerthanthesmallesttorsionalbacklashSa.a)Ifthegearisdirectlydependentonmorethan2bearings,caremustbetakentoensurethat’d2lanaoSLges-e)Forgearswithamoduleunder1andagradesmallerthan7,theholeinthegearshouldbeIfoneoftheserequirementsisover-steppedthenewconditionswhichresultregardingclear-ances,accuracyoftransmission,toothengagementconditions,etc.mustbechecked.equaltoorlargerthan1/5ofthepitchcirclediameter.Continuedonpages2to16leinverkaufderNormblätterdur&Beuth-VertriebGmbH,Berlin30undKölnDIN58405B1.2engl.F‘reisgr.--``,`,,`,,```,,`,`,,,``,```,`-`-`,,`,,`,`,,`---CIbcdefg,,,23415671819Toraional-Gear9dimensionreferenceeyatem2)MachiningSurface'3)Circum-iacklash863)forentialToothflankainTooth(incircularvalueamethodWm.Deak-todimonaion)mls0.g.1aoarfit5J/5f6J/6f7J17f8JPf6J/6a7JpdcûJ/ûdc9JPcd'1101/10e'1I1preciaionabove?20SehrgroundandUDto&poeiibijlapped~~Ger03milledprecision(it05TB,,,)'Iprecisionmilledorabove3'11Iz;1finishgroundupto12('to'Bm)abovo6'finiahedmilledupto24'I9051Ger1(1to5T.m)preciaiongear1prefer-ablyground1'1,51c;e:imilled(2to6'Bin)upto3(y(3to9TB3above8'andahavedfiniahedaboveupto4Tmilled(3to9T8ln)above8'milled,punchedoriprayedancesone)IIIlIII~urîacelJ)erm.peak-toalleyheigh14pmvvv4vmwv4CimvvvI4IJmwv4CimWVm716pmi6pmWI)SooroferencetoSupplomentuyShoot2inDIN58405Sheet1,page2.3)Theanglovaluositatodaroroferencovaluo.andapplytodrivenaccordingtoDIN58405Sheet1Sec-SchrIholicaltooth(notoaxialthruataanddeflectionofthogearblank;Ger=straightteeth.tion2oovoringrationwithibetvoon,?and6,numberoftooth&20andm=0.6mm.Themglovalue8itatodarorolatedtotholargogear.Foroxactcalculationoftorsionalbacklashindrivea,000DIN58405Shoat1Section3.6.1mmitiarecom-wndodthatapoaitiveaddendummodificationofx=4.5ahouldbeappliedtobothgears.I)OnlyformodulesmZ0.3mmwithoutaddendummodification.Inthocasoofmodules5)lormarking8.0DIN58405Sheet3Section3.6,lorballandrollorboaringa.Ifplainbearingsareuaed,theirdimensionalandgeometricalaccuracy7)SoeSootion1.208,Notethorialexpansionofhouaing.9,ThephysicalproportieaoftheplasticlaminateorofthemouldedmaterialorthermoplaeticueedmuetshouldbeinlinewiththecorreapondingiiwsforballboaringoaccordingtoDIN620.bOChoCkOd.lo)WhenballboaringaarewedDIN5425ihouldbenotedinconnectionuithsalectionofgrade.''1Minimumrequiromont,relatedtoexpanaionandatrength.12)TheI80toleranoe&oneatatedinbracket8ahouldpreferablybeusedforthegearborea(etandardmountingarboraforthemillingmachineandtentingmachines).Permissibleout-of-roundneseandvaria-tionfromthereferoncocylinderoftheboreare1/2ITofthegradeofboreconcerned.to-valleyheightfor6J/6i;6J/6eand7J/7dc,vhichhavebeenspecifiedaccordingtoRange4.'3)Correlationofpeak-to-valleyheight6accordingtoDIN3141Range3.exceptforthetoothflankpeak---``,`,,`,,```,,`,`,,,``,```,`-`-`,,`,,`,`,,`---DIH58405Sh