Numerical-Control數(shù)控技術大學畢業(yè)論文外文文獻翻譯及原文

畢設計論文）外文獻翻譯文獻、資中文題目：控技術文獻、資英文題目：Control文獻、資來源：文獻、資發(fā)表（出版日期：院（部專班姓學

業(yè)：級：名：號：指導教師翻譯日期2017.02.14NumericalControlNumerical(N/C)aformofinwhichprocessingequipmentisofnumbers,lettersandothersymbols.Thenumbers,letters,symbolscodedinanappropriateprogramofinstructionsaparticularworkpartjob.Whentheprogramofinstructionsbechanged.capabilitytoprogramiswhatN/Cforlow-volumeandItistomakealterationsofprocessingarebasictypesofnumericallycontrolledmachinepoint—to—continuouscalledPoint—to—machinesuseunsynchronizedmotors,withthatpositionofthemachiningbeassureduponcompletionofwhileonlymotorisrunning.oftypeprincipallyforstraight—cutsforTheN/Cconsiststhefollowingreaderwiththeunit,the—cuttingtooltypeofN/CDatainput,alsocalled“manto—controllink”,maybeprovidedthemachinetoolentirelybymeans.Manualmethodsusedthesourceofarelativelysmallnumberofinputs.Examplesofoperatedarekeyboardpushbuttons,switches,thumbwheelselectors.arelocatedonaconsolenearaledevicesusuallytosynchronization-typepotentiometer.cases,ofaredigitalinputManualinputthatsetcontrolseachoperation.ItaslowprocessisseldomjustifiedexceptinmachiningapplicationsinspecialInpracticallyinformationisautomaticallytocontrolunitthemachinebycards,byEight

—papercommonlyformofdatainputforN/CcodedinstructionsonofsectionsofpunchedholesEachamachinefunction,amachiningoraoftheN/Cprogramonofanofblocks,resultinginallonreelsmotion-picturefilm.onrelativelybecontinuouslybyjoiningendsoftheformainstalled,tapeiswithoutIncase,simplyPunchedalepreparedontypewriterswithtape—attachmentsorinconnectedcomputerrarelymaybeinitiallybythepartprogrammer,incardcompilation,aoftothetapeduringhandling,etc.SeveraltrialrunsarenecessarytoremoveallanacceptableworkingWhiledataontheisautomatically,stepsdoneBeforecodedtapemaybeprepared,oftenwithaorprocessengineer,theappropriateN/Cmachinetool,kindofmaterialtobecalculatethespeedsuponthetypeoftoolingneeded.dimensionsonprintcloselyexaminedasuitablezeroreferencepointfromtostarttheAprogramthenwrittenwhichcodedinstructionsthesequenceofoperationsthemachinerequiredtotocutparttodrawingTheunitreceivesstoresallcodeduntilcompleteblockofinformationbeenItthentheinstructionandthemachinetooltherequiredThefunctionofunitmayittoactionofdialdigititistheentirebeendialed,becomesactivatedandiscompleted.Siliconinthereaderonunit,lightasitthroughtheinthemovingThelightconvertedtowhichisamplifiedtostrengthenThesignalsintheunit,whereactuationrelayedtomachineSomedevicesarecapabletosecond.Highratesnecessarytomaintaincontinuous—toolmotion;otherwisebegeneratedbyonpartduringoperations.Thereadingdeviceofblocksratethansystemprocessdata.AfeedbackisausedonsomeN/CtocompensateforerrorsthetheofofmachineAnN/Cmachinewithkindofadirectfeedbackcheckingdevicewhatissystem.controlisaccomplishedawhich,duringtheoperation,thepositionofrelaysinformationbacktocontrolunit.receivedtoonbetweenthemInancalledanopenloopmachineispositionedsolelybysteppingmotorintoaarethreebasictypesoffollows:orControlInpoint-to-pointthemachinetooltable,etc.)movedThespeedofbetweenisonlythecoordinatesoftheofthecontrolled.Thistypeofcontrolissuitablefordrillpressessomeboringmachines,whereboringbeperformedlocationsontheworkorLinearControlsystemsaretomovecuttingtooltoofofthemachinetoolacontrolledsuitableformachining.Itisnormallymoveinonedirectionsocutsonnotformillingonlybemachinedorlathessurfacesparallelortotheaxiscantypeofmotionisaslinearcontrolacontrol.Machineswiththisformofcontrolarealsocapablepoint-to-pointContinuousPathorContouringControlIncontinuouscontrolthemotionsoformoreofmachineaxesarecontrolledsimultaneously,thatpositionvelocityofthecanbetoolInwaycurvessurfacesbemachinedatcontrolledfeedrate.Itofinterpolatorinthecontrollertodetermineoftheindividualcontrolledaxesofmachinestoproducetypeoftoascontinuousorafullaxisofcontrol.SomeconcerningmotionsforNChasbeenexample,areasfour-orfive-orevensix-axisForverticalmachinethreeoffairlyobvious,thesebeingtheusualX,YZdirections.AfourthfifthaxiswouldimplyformrotarytabletoindexworktoprovideangularmotionoftheworkThus,inNCanaxisofcontrolanycontrolledmotionofmachine(spindles,tables,Acomplicationuseoftermhalf-axisofforexample,manymillingmachinestoasThismeansthatcontinuouscontrolformotions(axes)andonlylinearcontrolfortheAppliedverticalmillingmachines,controlmeanscontouringintheX,YplanelinearmotioninZdirection.WithhavetobewitharoundthedifferentWithansamemachinecouldbecalleda2CLmachine(CforLforlinearcontrol).amachinewithcontinuouscontrolinX,Y,Zdirectionsbebemachineora3cSimilarly,usuallytwoorTheofprecisionalmostentirelyupontheofscrewtheofmachinestructure.thisthereisnoself-correctingactionfeedbackoftheIneventanunexpectedmalfunction,theoutpulsesofelectricalcurrent.If,forexample,onanN/Cmillingwerenoresponsewouldbetosteppingmotorsnotvariations,N/Carepermittostallwhentheresistingexceedsthemotortorque.Otherareinuse,whichinofpossibilityofthemachinestructureortosystem,alewith—steppingmotors.Inthemotorshavesufficientcapacityto“overpower”thesystemtheeventofalmostanycontingency.Theoriginalusedthe—system.Ofopenloop,loopand,aconsequence,isexpensive.Initially,openloopsystemswerealmostentirelyforapplicationsbecauseofpreviouslyassociatedwithelectricsteppingadvancesinofelectrosteppingmotorsledtoincreasinglymachine數(shù)控技術數(shù)控是可編程自動化技術的一種形式通過數(shù)字字母和其他符號來控制加工設備數(shù)字字母和符號用適當?shù)母袷骄幋a為一個特定工件定義指令程序當工件改變時指令程序就改變這種改變程序的能力使數(shù)控適合于中小批量生產，寫一段新程序遠比對加工設備做大的改動容易得多。數(shù)控機床有兩種基本形式點位控制和連續(xù)控制(也稱為輪廓控制)點位控制機床采用異步電動機因此主軸的定位只能通過完成一個運動或一個電動機的轉動來實現(xiàn)。這種機床主要用于直線切削或鉆孔、鏜孔等場合。數(shù)控系統(tǒng)由下列組件組成數(shù)據輸入裝置帶控制單元的磁帶閱讀機反饋裝置和切削機床或其他形式的數(shù)控設備。數(shù)據輸人裝置，也稱“人機聯(lián)系裝置用人工或全自動方法向機床提供數(shù)據人工方法作為輸人數(shù)據唯一方法時只限于少量輸入人工輸入裝置有鍵盤撥號盤按鈕開關或撥輪選擇開關這些都位于機床附近的一個控制臺上。撥號盤通常連到一個同步解析器或電位計的模擬裝置上大多數(shù)情況下、開關和其他類似的旋鈕是數(shù)據輸入元件人工輸入需要操作者控制每個操作這是一個既慢又單調的過程，除了簡單加工場合或特殊情況，已很少使用。幾乎所有情況下息都是通過卡片紙帶或磁帶自動提供給控制單元。在傳統(tǒng)的數(shù)控系統(tǒng)中八信道穿孔紙帶是最常用的數(shù)據輸入形式紙帶上的編碼指令由一系列稱為程序塊的穿孔組成每一個程序塊代表一種加工功能一種操作或兩者的組合紙帶上的整個數(shù)控程序由這些連續(xù)數(shù)據單元連接而成帶有程序的長帶子像電影膠片一樣繞在盤子上對較短的帶子上的程序可通過將紙帶兩端連接形成一個循環(huán)而連續(xù)不斷地重復使用帶子一旦安裝好就可反復使用而無需進一步處理。此時，操作者只是簡單地上、下工件。穿孔紙帶是在帶有特制穿孔附件的打字機或直接連到計算機上的紙帶穿孔裝置上做成的帶制造很少不出錯，錯誤可能由編程、卡片穿孔或編碼、紙帶穿孔時的物理損害等形成。通常，必須要試走幾次來排除錯誤，才能得到一個可用的工作紙帶。雖然紙帶上的數(shù)據是自動進給的但實際編程卻是手工完成的在編碼紙帶做好前編程者經常要和一個計劃人員或工藝工程師一起工作選擇合適的數(shù)控機床，決定加工材料，計算切削速度和進給速度，決定所需刀具類型，仔細閱讀零件圖上尺寸定下合適的程序開始的零參考點然后寫出程序清單其上記載有描述加工順序的編碼數(shù)控指令，機床按順序加工工件到圖樣要求?？刂茊卧邮芎蛢Υ婢幋a數(shù)據直至形成一個完整的信息程序塊然后解釋數(shù)控指令，并引導機床得到所需運動。為更好理解控制單元的作用將它與撥號電話進行比較每撥一個數(shù)字，就儲存一個，當整個數(shù)字撥好后，電話就被激活，也就完成了呼叫。裝在控制單元里的紙帶閱讀機通過其內的硅光二極管檢測到穿過移動紙帶上的孔漏過的光線將光束轉變成電能并通過放大來進一步加強信號然后將信號送到控制單元里的寄存器，由它將動作信號傳到機床驅動裝置。有些光電裝置能以高達每秒個字節(jié)的速度閱讀，這對保