KISSsoft塑料齿轮齿廓修形篇

Plastic

Gears

ProfileoptimisationKISSsoftPlasticgearprofileoptimisationWewilllook

at

the

following

profile

modificationsTipandrootreliefProfilecrowning/barelling(centricandeccentric)PressureanglemodificationWewilllearnaboutafunctionhowtofindthebestpossiblecombinationofprofilemodificationsNotethatyoushouldapplyatiproundingbeforeyouusethebelowfunctionbecausethetiproundingaffectsthetipformdiameterdFa!1)ProfilemodificationsProfilemodifications

BasicconsiderationsThebasic

task

isFindasuitableprofilemodificationThatgivesgoodresultsintermsofe.g.Lowpeak-to-peaktransmissionerrorLowwearrateLowcontactstress…UndertheconditionthatitworksfordifferentloadlevelsAndthenexporttheresultinggeometryfortoolingThekeydifficultyis:ONEmodificationshouldbesuitableforMANYloadlevels.Forexample,amodificationthatgiveslowvibrationataparticularloadlevelbuthighvibrationatanotherisNOTsuitable.Profilemodifications

DefinitionsinKISSsoftThedesignofgearmodifications(forplasticgears,mostlyprofilemodifications)isoneofthekeytasksforhighperformancegears,wherehighperformancemaybedefinedas,amaximizedtorquecapacity,minimizedvibrationlevelorlowestwearrisk.Gearmodifications,orthegearmicrogeometry,areassessedinthetoothcontactanalysisTCAwherethetruegeargeometry,consideringbothgearmacroandmicrogeometryandgearmisalignment.The

profile

modification

may

be

considered

asatoothformmodification

and

are

discussed

here.Thetooth

contact

analysis

isnotdiscussedhere.For

tolerance

bands

refer

toANSI/AGMA2000-A88,ISOTR10064-1.ForprofilemodificationsinKISSsoft,ISO21771isusedmostly.Profilemodifications

TipandrootreliefTip

and

root

reliefCαaCαf:Tipreliefmaybeaddedtogear1orgear2orbothinamesh.Ifyouwanttoconsiderthemodificationonbothgears,usetwolines.Selectthetypeof

tip

relieffromthelist„Typeofmodification“In„Value“,enterthevalueforCαaandCαfinum„Factor1“definesthelengthoftherelief/it‘sstartposition,asamultipleofthemodule,measuredfrompointAandErespectivelyUsing

the

flag„Status“,you

may

use/notuse

the

modificationinaparticular

calculation.Profilemodifications

Differenttypesoftip/rootreliefProfilemodifications

Differenttypesoftip/rootreliefProfilemodifications

Differenttypesoftip/rootreliefProfilemodifications

Differenttypesoftip/rootreliefProfilemodifications

Differenttypesoftip/rootreliefDifferenttypes

of

tip

and

root

relief:Therearefortypes:linear,curved(circular),progressive(polynom)andcurvedwithtransitionradiusProfilemodifications

ProgressivereliefThecurvature

of

theprogressive

relief

may

be

changed:Use„Factor2“todefinethe„factor“inthebelowformulaAgoodvalueis75->linearrelief 20->strongcurvatureProfilemodifications

PressureanglemodificationProfileslope

modificationCHαWiththis,thepressureangleofthegearismodified.ItmayalsobeunderstoodasatipreliefthatstartsattherootformdiameterdFfProfilemodifications

Profilecrowning/barrelling2)Sizingfunction

Sizingfunction

KISSsoftusageInKISSsoft,there

are

three

sizing

functions

for

geardesignThe„Roughsizing“The„Finesizing“The„Modificationssizing“TheyallworkonasimilarprincipleDefinebasicrequirementsofthegearsetDefineaparameterrangeKISSsoftwillsearchallpossiblesolutionswithintheparameterrangeTheuserwillfilterthesolutionsaccordingtohisrequirementsTofind„thebest“solutionLoaddata,material,…SizingFunctionMultiplesolutionsFilterBestsolutionParameterrangesfor…Sizingfunction

Tab„Conditions“Tab„Conditions“:hereyoudefinetheparametersfortheoptimisationrun.Youcandefinethreegroupsofmodificationsthatarevaried.YoumayconsiderarangeoftheloadForeachmodificationgroupandfortheloadrange,youmaydefinethestepnumberSizingfunction

Tab„Conditions“Youmaydefineseveralmodificationspergroup.Foreachmodification,enteraminimumandamaximumvalue.Betweenthisminimumandmaximumvalue,thevaluewillbevariedsuchthatanumber(=stepnumberasdefinedatlowerendofwindow=ofdifferentmodificationsarechecked.Ifyouhaveenteredmodificationsinthetab„Modifications“already,theyaretransferedhereautomatically.Sizingfunction

Tab„Conditions“

Thenumberofsolutionsgeneratedisns^i*nl+nlWhere: nsisthenumberofstepsforthemodifications nlisthenumberofstepsfortheload i=1ifmodificationsareingroupAonly,i=2ifinAandB, i=3ifinA,BandCNotethatinanycase,thecalculationisalsoperformedforagearsetwithoutanymodificationsforcomparison,forallloadlevels.Hencetheterm„+nl“.Sizingfunction

Tab„Conditions“

InthebelowexampleThetiprelief(inGroupA):fivestepsThelowesttipreliefis20um,thehighestis60umThetipreliefwillhencebe20um,30u,40um,50um,60umsimultaneouslyforbothgearsThestartoftipreliefandthecurvatureisnotvariedProfilecrowning(inGroupB):fivestepsThelowestprofilecrowningis0um,thehighestis20umTheprofilecrowningwillhencebe0um,5um,10um,15um,20umFourloadlevels:70%,80%,90%and100%load.Givingatotalof100combinationsSizingfunction

Tab„Results“

TheresultstableshowFirsttheresultswithoutmodificationsforthedifferentloadlevelsThentheresultswithmodificationsforthedifferentloadlevelsDifferentresultsarelistedUserightmouseclicktoaddandremovecolumnsUse„Shift“and„Ctrl“toselectmultiplerowsUse„Delete“todeletesomeresultsUse„Accept“tousethemodifications/transferthem intothetab„Modifications“Sizingfunction

Tab„Results“

Sizingfunction

Tab„Graphics“

ThegraphicsshowDifferentresultsforthedifferentmodifcations/differentloadlevelsRed:highestload,blue:lowestloadUsemultiplegraphstocomparedifferentpropertiessimulatneouslySelectresulttypeSelectindividualloadlevelsSelectnumberofgraphsUse„CtrlC“+“CtrlV“tocopy/pastgraphSizingfunction

Tab„Graphics“

ThegraphicsshowResultswithoutmodificationsThedifferentcombinationsofmodifcationsTheresult/valuesUsezoomandotherfunctionsthroughrightmousecl