教学材料《数控技术英语》-Unit 4 CNC machine tools

TextNCisbeingusedalltypesofmachinetools,fromthesimplesttothemostcomplex.NCmachinetoolsweredevelopedonthebasisofgeneral-purposemachinetools.VarioustypesofNCmachinetoolsoriginatedfromthesametypesofgeneralpurposemachinetools.SinceNCmachinetoolshavebeendevelopedforoverfortyyears,theyhavemanyspecificationsandtypes，andtheirsstructureandfunctionshavetheirownfeatures.InordertounderstandNCmachinetools,weintroduceseveralmainCNCmachinetoolssimply.1.NCturningmachineThefollowingfigureshowstheappearanceofNCturningmachine.Itisoneofmostproductivemachinetools.ThebodyofNCturningmachineincludesaspindle,anapronandatoolpost.NCsystemconsistsofCRTdisplay,controlpanelandheavy-currentcontrolsystem.下一页返回Text2.NCmillingmachineFig4-2NCmillingmachineNCmillingmachinehasalwaysbeenoneofthemostversatilemachinesusedinindustry.Operationssuchasmilling,contouring,gearcutting,drilling,boring,andreamingareonlyafewofthemanyoperations.NCmillingmachineissuitableforprocessing3dcomplexcurvedsurface,findingwideapplicationinautomobile,aerospace,dieequipment.IntheworldthefirstNCmachinetoolcamefromNCmillingmachine.Butwiththedevelopmentoftimes,NCmillingmachinetendstomachiningcenter.Atpresent,becauseoflowprice,convenientandflexibleoperation,shorttimeforworkingpreparation,NCmillingmachineisstillwidelyinuse,classifiedasNCverticalmillingmachine,horizontalmillingmachineandNCcopyingmillingmachine.下一页上一页返回Text3.MachiningcenterMachiningcenterisaproductwhichNCmachinetoolsdevelopedtoacertainstage.Sofar,machiningcenterisn’tclearlydefined.NCboringandmillingmachineequippedwithautomatictoolchangerisgenerallyconsideredasmachiningcenter.Actually,machiningcenterissummedupinthephrase“withautomatictoolchanger,capableofmoreprocessesmachining.”Machiningcentercanperformmilling,boring,drilling,reamingandtapping,whicheliminatestheneedforanumberofindividualmachinetools.Thus,itreducescapitalequipmentandlaborrequirements.Machiningcentercanbedividedintoverticalmachiningcenter,horizontalmachiningcenter.Thespindleofverticalmachiningcenterisperpendicularandthespindleof下一页上一页返回Texthorizontalmachiningcenterishorizontal.Verticalmachiningcenterscontinuetobewidelyacceptedandused,primarilyforflatpartsandwherethree-axismachiningisrequiredonasinglepartfacesuchasmoldanddiework.Horizontalmachiningcentersarealsowidelyacceptedandused,particularlywithlarge,boxy,heavypartsandbecausetheylendthemselvestoeasyandaccessiblepalletshuttletransferwhenusedinacellorFMSapplication.Aworkpiececanbeputonarotatingtableorexchangingpalletbyusingafixture.Polyhedroncanbeproducedbythetablerotatingandtheexchangeofthepalletcanchangethemachiningworkpieceforimprovingthemachiningefficiency.下一页上一页返回Text4.NCdrillingmachineThefigure4-5showsNCdrillingmachine.ItcanbedividedintoverticalNCdrillingmachine,horizontalNCdrillingmachine.NCdrillingmachinecanperformdrillingandtapping,alsosimplemilling.Itstoolmagazinecanstorevarioustools.5.NCgrindingmachineNCgrindingmachinesareusedtomachinehighhardnessandprecisionmachiningsurface.ItisclassifiedasNCsurfacegrinder,NCinternalgrinderandNCprofilegrinder.Withthedevelopmentofautomaticgrindingwheelcompensation,correctionandgrindingfixedcycletechnology,thefunctionofNCgrindingmachineisstrongerandstronger.下一页上一页返回Text6.NCelectricaldischargeformingmachineEverymachinistknowsthatonstandardmachinetoolselectricalenergyisconvertedintomotionbyanelectricmotor.Nowadays,ithasbeendiscoveredthatelectricalenergycanbedirectlyemployedinmetalremoval.NCelectricaldischargeformingmachineisaspecialmachiningmethod,utilizingtwodifferentpolaritiesofelectrodetogeneratedischargeintheinsulatorforremovingmaterialandfinishingmachining.Ithasthespecialadvantageinmachiningcomplexdieanddifficult-to-machinematerials.下一页上一页返回Text7.NCwire-cutmachinetoolTheworkingprincipleofNCwire-cutmachinetoolisthesameastheprincipleofelectricaldischargeformingmachinetool.Itselectrodeiselectrodewireandprocessingliquidgenerallyusesdeionizedwater.上一页返回WordsandExpressionsmaterialn.1.材料,原料；2.素材,资料；originatevi.起源于,来自,产生；vt.创造,创始,开创;发明specificationn.1.规格,说明书,详细的计划书productiveadj.1.富有成效的,有益的;2.生产性的;paralleladj.平行的;n.平行线;vt.与…平行,与…相当;perpendicularadj.1.垂直的,成直角的;2.直立的;3.垂直式的appearancen.1.出现,显露;2.外观,外貌,外表;carriagen..刀架下一页返回WordsandExpressionsindexingn.标定指数aerospacen..航空航天工业;adj.宇宙空间的,宇宙航行的apindlen.主轴apronn.溜板contouringn.轮廓,造型automobilen.〈美〉汽车dien.1.(用于金属等材料加工的)模具;2.（集成电路的）芯片块模具reamingn.铰turningn.车削;旋转下一页上一页返回WordsandExpressionsmilling铣削drillingn.钻孔boringn.镗削tappingn.攻丝palletn.托盘,垫盘,托板utilizevt.利用,使用dischargevt.&vi.放出,流出electroden.电极 turningmachine车床 verticalmillingmachine立式铣床horizontalmillingmachine卧式铣床下一页上一页返回WordsandExpressionsmachiningcenter加工中心electricaldischargeformingmachine电火花成形机床grindingmachine磨床surfacegrinder平面磨床internalgrinder内圆磨床profilegrinder轮廓磨床 toolmagazine刀库wire-cutmachinetool线切割机床capitalequipment主要设备crossmotion横向运动gearcutting齿轮加工curvedsurface曲面上一页返回Notes1.Earlymachinetoolsweredesignedsothattheoperatorwasstandinginfrontofthemachinewhileoperatingthecontrols.老式机床是按操作者站立在机床前进行操作设计的。注：句中sothat引导的是结果状语从句。2.Withtheadditionofelectroniccontrols,actualtimespentremovingmetalhasincreasedto80percentandevenhigher.随着电控设备的加入，实际切削材料的时间已增至80%以上。

withtheadditionof随着……的加入

Withtheadditionofnewtechnology,thefunctionofmachinetoolsismoreandmore.下一页返回Notes3.Ithasalsoreducedtheamountoftimerequiredtobringthecuttingto