試驗(yàn)指導(dǎo)書五軸數(shù)控磨刀機(jī)原理及實(shí)踐

實(shí)驗(yàn)指導(dǎo)書五軸數(shù)控磨刀機(jī)原理及實(shí)踐要加工出合格的工件,必須根據(jù)工件的加工工藝要求,正確地設(shè)計(jì)和使用刀具,以保證到達(dá)工件所要求地尺寸、形狀精度和外表質(zhì)量.金屬切削刀具的種類很多,對于標(biāo)準(zhǔn)刀具,需要根據(jù)刀具的工作原理和結(jié)構(gòu)特點(diǎn)正確地選擇和使用；對于非標(biāo)準(zhǔn)刀具那么需要根據(jù)工件的加工要求進(jìn)行專門的設(shè)計(jì)和制造.經(jīng)過精心準(zhǔn)備,?制造工程根底?教學(xué)組與德國saacke公司培訓(xùn)中央嘗試進(jìn)行校企合作開展學(xué)生實(shí)驗(yàn)課程的工作.本次實(shí)驗(yàn)的主要目的是結(jié)合生產(chǎn)實(shí)際,通過先進(jìn)的制造設(shè)備及手段,使學(xué)生能夠掌握刀具的設(shè)計(jì)原理,合理選擇刀具設(shè)計(jì)參數(shù),正確設(shè)計(jì)刀具結(jié)構(gòu),熟悉刀具從設(shè)計(jì)到制造的全過程..實(shí)驗(yàn)?zāi)康?結(jié)合生產(chǎn)實(shí)際,給學(xué)生介紹先進(jìn)的生產(chǎn)理念,作為課堂內(nèi)容的拓展和補(bǔ)充,加深對所學(xué)知識的理解；.鍛煉實(shí)驗(yàn)設(shè)計(jì)水平和動手水平,熟悉刀具由設(shè)計(jì)到制造的全過程；.掌握有關(guān)磨削加工的知識,了解刀具磨床的結(jié)構(gòu)及工作原理,；.掌握鉆頭設(shè)計(jì)、加工的全過程；.指導(dǎo)人員德國Saacke公司中國工程師、德國工程師(英語交流)、實(shí)驗(yàn)指導(dǎo)教師.實(shí)驗(yàn)內(nèi)容由Saacke公司的指導(dǎo)人員負(fù)責(zé)講解,并利用該公司所提供的五軸數(shù)控磨刀機(jī)及相應(yīng)的CAD/CAM軟件,參加實(shí)驗(yàn)的每組同學(xué)完成所選刀具的設(shè)計(jì)和制造.本實(shí)驗(yàn)主要包括以下內(nèi)容：講解Saacke五軸新概念刀具磨床的結(jié)構(gòu)及工作原理.講解鉆頭、銃刀等刀具設(shè)計(jì)、加工原理講解有關(guān)磨削加工的知識,包括砂輪、切削液等在刀具設(shè)計(jì)加工仿真軟件上完成相應(yīng)刀具的CAM設(shè)計(jì)在Saacke五軸刀具磨床上完成所設(shè)計(jì)刀具的加工.實(shí)驗(yàn)設(shè)備、儀器及工具.機(jī)床：uwn型五軸數(shù)控磨床.軟件：NUMROTOplus.試件：45#鋼棒料〔細(xì)長棒料〕.計(jì)算機(jī).千分表、游標(biāo)卡尺.刀具角度測量儀.準(zhǔn)備工作.熟悉鉆頭、銃刀的結(jié)構(gòu)特點(diǎn)、設(shè)計(jì)原理和制造方法;.熟悉本指導(dǎo)書附錄中關(guān)于磨削的知識；.牢記操作考前須知及操作平安..UWII型五軸數(shù)控磨床簡介圖1.uwn型五軸數(shù)控磨床UWH型五軸數(shù)控磨床,功率15KW,可以用于刀具的制造和修磨,并可配置自動上下料裝置,以滿足大批量生產(chǎn)的需要.機(jī)床采用Windows操作系統(tǒng),人機(jī)對話式窗口,界面友好,旁邊有圖形支持窗口,可對加工刀具進(jìn)行三維立體顯示和加工模擬,并且留有用戶開發(fā)界面.在磨頭上裝有三維Renishaw測頭,可以對刀具的長度、直徑、螺旋角等參數(shù)進(jìn)行自動測量,并自動輸送到計(jì)算機(jī)中,方便可靠.該機(jī)床主要技術(shù)參數(shù)如下：技術(shù)特點(diǎn)：—轉(zhuǎn)塔式磨頭,裝有三根砂輪芯軸,可配9片砂輪一磨軸馬達(dá)功率15KW一數(shù)字限制

一磨軸轉(zhuǎn)速2,000-8,000rpm一工件頭直接驅(qū)動,轉(zhuǎn)速600rpm(可選)—自動上料系統(tǒng)(可選)—每個(gè)托盤最多可裝40把刀具工件參數(shù)：300mm2300mm250mm350mm一全磨制最大直徑一全磨制最大切削刃長七.實(shí)驗(yàn)報(bào)告.實(shí)驗(yàn)?zāi)康?實(shí)驗(yàn)內(nèi)容.實(shí)驗(yàn)步驟.實(shí)驗(yàn)結(jié)果利用刀具設(shè)計(jì)加工CAD/CAM軟件系統(tǒng)NUMROTOplus完成相應(yīng)刀具的CAM設(shè)計(jì)利用uwn型五軸數(shù)控刀具磨床和棒料加工出所設(shè)計(jì)的刀具給出設(shè)計(jì)加工的鉆頭的測量角度.實(shí)驗(yàn)分析與總結(jié)分析所設(shè)計(jì)鉆頭結(jié)構(gòu)特點(diǎn)和刀具幾何參數(shù)對加工的影響；分析五軸數(shù)控磨床的工作原理以及砂輪的特性由哪些因素決定；分析切削液的種類及切削液的使用情況對磨削加工的影響；對本次實(shí)驗(yàn)的感想與建議；.建議建議大家在實(shí)驗(yàn)前做好準(zhǔn)備工作,在實(shí)驗(yàn)中每組同學(xué)可進(jìn)行分工,以提升實(shí)驗(yàn)效率.附錄GrindingGeneralintroductionGrindingmeanscuttingwithgeometricallynotdefinededges.Therotatinggrindingbodiesarecomposedofboundabrasivegrainsandimbeddedpores,functioningas"chipchambers〞兒AdvantagesofgrindingHighsurfacequalityofthegroundpartsGoodmachinabilityofhardanddifficulttomachinematerialsHightimegrindingvolume.Partially,similarvaluesasforplaningandturningarepossible.SurfacegrindingmachinesOnsurfacegrindingmachinesplanesurfacesaremachinedbytheperipheryorbythefaceofthegrindingwheel(figure).Therearedifferentkindsofmachines:oneexecutionwithhorizontalandverticalgrindingspindle,theotherwithlongandwithrotarytable.Longtablesaremeantforbiggerresp.longerworkingpieces.Roundorrotarytablesaresuitedforsmallerpieces.Smallerpiecesdonotneedthechangeofdirectionattheend.Thereforeacontinuousfeedmotionispossible.Ongrindingmachinesthetool(grindingwheel)iseffectingthecuttingmovement.Dependingonthemachinetypeordesign,theplungeandthefeedmotionareeffectedeitherbytheworkingpieceorbythetool.SurfacecylindricalgrindingmachinesOnthesemachinestheworkingpieceismostlyclampedbetweenthecenters.Itgetsarotarymotion.Thecuttingmovementiseffectedbythegrindingwheel.Thegrindingwheelcanbefedfrombehindtotheworkingpiece.Longworkingpiecesrequirealongitudinalfeed(figure),whichismostlyeffectedbytheworkingpiece.Hereaslide(workingpieceslide)isrequired,whichcanbeadjustedtodifferentstrokelengths.Theworkingpiecetableisfixedontheslide.Machineswithahorizontalspindlearemostlyusedforperipherygrinding.Infigure?youcanseedifferentexamplesofuse.Verticalspindlesareoftenusedforfacegrinding.Onbothmachinetypestheslidesaremostlyhydraulicallyoperated.Hydraulicdrivesarevibrationfree,thefeedisinfinitelyvariable.Highqualityslideguidesandgoodlubricantconditionsontheguidesurfacesareveryimportantinordertoavoidthestick-slip-effect.Alsoveryimportantaregoodspindlebearingassemblies.References/characteristicsofagrindingwheelOnfigure1(pagel)youcanseethebodyofagrindingwheel.Thefigureshowstheabrasivegrains,thebondingmaterialandthepores.Whenselectingthesuitablegrindingwheel,fivedecisionshavetobemade.1Abrasivematerial(chemicalcompositionoftheabrasivegrain).Themostimportantabrasivematerialsare:corundumA,siliconcarbideC,boronnitrideBanddiamondD.Corundumsaremainlycomposedofaluminiumoxide(AI2O3).Youhavetodifferbetweenseveraldegreesofpurity.Normalcorundum:94...97H%AI2O3.specialfusedalumina:morethan99%AI203Coojndumsareforexamplesuitedforthegrindingoflongcuttingmaterials.Siliconcarbideisharder.Itissuitedforthegrindingofshortcuttingmaterialsasforexamplegrayiron,chillcasting,carbide.?grabrrrtttri?.|Mme30.702.Granulation(grainsize)8■c36IGAInthestandarddesignationthegrainsize?w12isspecifiedwithanumber,forex.80.141660170]b0Itspecifiesthenumberofmeshes(per20inch)241000ofafilterbywhichthegrainswere1200sortedout.Hardness(Resistanceofthegrainsagainstbreakingoutofthebonding).Aseverycuttingtooldoes-grainsaredullingafteracertaintime.Whenthewheelhardnessisselectedcorrectly,thedulledgrainbreaksoutduetothehigherloadingandallowstherefore,thatnew,sharpgrainscanwork.Thematerialoftheworkingpiecehasabiginfluenceonthehardnessselection.Hereyouhavetoconsider:Hardmaterialsrequiresoftwheels,softmaterialsrequirehardwheels.WhWhenhardmaterialsaremachinedthegrainsaredulledearlierandhavetodisconnectearlierfromthebonding.Thehardness(oneletterforex."M')referstothestationarywheel.AecDwochEFG—攵hrw?ichH1Jo<KWCKhLMNOmittrlPaRshenTuVwwhrhartXYZ?Au&ef&thartAArtificialresin-Bondingscontactzone).Duringinternalgrindingthegrainischargedlessandreststhereforelongerinthebonding.Sothewheelseemsharder.Inthefollowingyoufindotherpossibilities,howtoincreasetheactivehardness(precondition:theothermachiningdatastaythesame).settinganewgrindingwheel(duetothebiggerdiameter)increasingthecuttingspeed(chipsectiongetssmaller).reducingthecuttingdepth.Selection:Jotcommentforselection:Thecutterhasahardnessof61HRC.HereyoushoulduseagrindingwheelsofterthanJot.Fortheselectionhowever,measureandformprecisionhavetobetakenintoconsideration.Softgrindingwheelswearoutfaster.Andsoitismorediffculttokeepthegivenformandmeasuretolerances.Structure(spaceportionofgrains,bondingmaterialandpores)1234567891011121314<一openstructure—>Theporesarenecessaryaschipsections.Theirsizeandquantityhavealsoinfluenceonthehardness(seeabove).Awheelbeingtootightistoohardandhastoolowefficiency.Withawheelbeingtooopen,itmightbedifficultdogetacertainsurfacequality.Ascharacteristicforthestructureanumberisused.Selection:structure5Bonding(material,whichbindsthegrains)Thebondingisalsoresponsibleforthehardnessandespeciallyfortheelasticityofthegrindingwheel.Thebondinghastoendureamechanicalandalsoaveryhighthermalloading.Inthefollowingtherearementioned2kindofbondinQCharacteristicsCeramic?goodhardnessgraduationpossibilities荻錠‘?Bondingsresistanceagainstwaterandoil也舞礁\V*indifferencetohighheating,but您修浦擊sensitivitytoimpactsmuchmoreelasticthanceramicbondings(especiallyimportantforthingrindingwheels)Bytheelasticattitudethegrainsareprotectedagainstoverload.Selection:V(CeramicBonding)Thestandarddesignationofthechosengrindingwheelis:Grindingwheel.用69120*250*2576慶60內(nèi)5VCheckanddressingofthegrindingwheels,rulesforpreventionofaccidentsDuringgrindingthedangerofaccidentsisveryhigh.Whenthegrindingwheelbreaks,thepartsflyingaroundmaycauseadeadlyaccident,iftheyarenotcaughtbyaprotectingdevice.Thefollowingrulesforpreventionofaccidentsarealsoincludingthefieldoffreeformgrinding,(grindingofknifes,scissors,etc.)Beforedressingthegrindingwheelyouhavefirsttoeffectanacoustictest.Thewheelhastobekeptintheboreandisslightlyhitforex.withapieceofhardwood.Thesoundmustbehigh.Theflangesmusthavethecorrectsize(S>1/3Dwhenusingprotectivecaps.S=2/3Dwithoutprotectivecaps,S=112Dforconicalwheels.Theflangesmusthavethesamesize.Youmustputintermediatelayersoutofelasticmaterialbetweentheabrasivewheelsandthedampingflanges(forex.rubberorfelt).ThusirregularitiesonthegrindingwheelsurfaceshallbecompensatedThegrindingwheelmustbeeasytosliponthespindle.Whenyouhavesimplegrindingmachines,theworkrestshavetobeputclosetothegrindingwheelandhavetobereadjustedregularly.Pleasepayattentiontothemaximumrotationfrequency.Onthegrindingwheelyoucanseethemaximumallowableperipheralspeed,forexonabluestripe(blue:vc<45m/s).Beforethefirststartpleasetakecarethatnotoolsorotherthingsmaybeacquiredbythegrindingwheel.eAftereachnewsettingyouhavetoeffectatestrunningofatleastfiveminuteswiththeratedmaximumrotatingfrequency.Duringgrindingyouhavetowearprotectivegoggles.BalancingDuringgrindingyouworkwithhighperipheralspeedsandthereforealsowithhighrotatingfrequencies.Whenusingunbalancedgrindingwheels,youhavetoexpectunbalanceandthecorrespondingcentrifugalforce.Unbalancedgrindingwheelscausevibrations,whichmayimpairthesurfacequalityandreducethelifeenduranceofthegrindingwheelandthemachine.■■■■I?.SH■■■■I?.SHUFlart^h-HjITi/ZwischecMe^r.rSAACKEWorkshopGrindingThegrindingwheelshavetobebalancedtogetherwiththeirflanges.Inmanycasesstaticbalancingwithcompensationmassesissufficient.Thegrindingwheelsatisfiesineachpositionthemasspoint.Iftherearehighdemandsresp.verylargewheels,youhavetobalancedynamically.CylindricalgrindingsurfacecylindricalgrindingThestud025mmofthebevelpinionhasalengthof20,3mm.Ifyouhaveagrindingwheelwidthof25mmitispossibletofinishthediameterwithoneplunge-cutThisworkingmethodiscalledcrossgrinding.Duetotheshortproductioncycleitisveryeconomical.Aftergrindingthediameter,theendfacehastobemachined.Thisprocessiseffectedwiththefrontfaceofthegrindingwieel.Bybevelingitispossibletomachinebothsurfacesinthesametimewithoneplunge-cut.Wfilegrindingiseffected.Withthismethodacertaincontouriscompletedbyoneplunge-cut.Forlongerpartsyouneedeitheralongitudinalfeed(swinggrinding)orseveralplunge-cutsareplacedsidebyside.Thefirstpossibilityyoufindmoreoften,forexbecausebythismethodyoucanreachacontinuouschipremoval,theproductiontimeisreduced.Fortheswinggrindingthegrindingwheelhastohavealittleoverrun(1/3to1/4ofthewheelwidth).Ifnot,attheendsitwillnotbepolishedenough.Forthebearingdiameter40mmofthedrivegearwheelthefollowingshiftisnecessary:L=L+1Z3*BL:shiftlengthI:pinlengthattheL=54mm+1/3*25mmworkpiece(54mm)L?63mmB:grindingwheel-width(25mm)Duringgrindingthegrindingwheelmaybeapproachedverysensitively,Uiescaledivisionvalueamountsmostlyto1pm.Forautomaticapproachamargin(byamechanicaldevice)ispossible.However,afterdeactivationofthefeedthewheelcontinuesgrinding"outsparking".Thatwaytherespectofthemeasuretolerancesisverydifficult.Ameasurecontrolterminatesthegrindingprocessassoonastherequiredmeasureisreached.Centerlesssurfacecylindricalgrinding.Thespecialtyofthismethodisthattheworkpieceisnotfixedinaclampingdevice,butliesfreeonahardrest.Aregulatingwheelsupportstheworkpiece,inthesametimethewheeltransfersitsperipheralspeedontheworkpieceandenablessothegrindingprocess.PlaneorsurfacegrindingForthegrindingofplanesurfacesthereexistparallelstomilling.Howevertheconsiderationsofthemillingcannotsimplybetransferred,becausethetoolhasanotherstructureandbecauseyouworkwithotherspeeds.Duringthefacegrindingthereisabigcontactareabetweenthegrindingwheelandtheworkpiecesurface.Therearethefollowingdangers:Intenseheatgeneration(duetothebigcontactarea).Forhardenedpiecesthestarttemperaturecanbeexceededlocally.Thatmeans:softareasaregenerated.Onaclosedfrontfacethechipsandalsothebrokenoutgrainshavedifficultiestocomeout.Thewheelcanbeclosedfromthechips.PoPossiblecountermeasuresarethefollowing:2X2XnncmsATbMStur3TdUfirftw.twScZrfM'Eon21Wcrk/rjucn4/yHdKhondgg5SdzDiscontinuitiesinthegrindingwheels(forex.segmentalwheels).Insomecasesitispossibletoinclinethespindle.Herebyhoweverthereareformdeviationsatthewxkpiece.Themachiningofthediscontinuedsurfacesisfavorable.Herebythegrainsagainandagainhitfreespaces,wherethechipsarekickedoffandwhereisnofriction.Alsothesingleedgescanere-touch".Duringperipherygrindingthecontactareabetweengrindingwheelandworkpieceisrelativelysmall.There