機械類外文文獻翻譯

文獻翻譯英文原文：NOVELMETHODOFREALIZINGTHEOPTIMALTRANSMISSIONOFTHECRANK-AND-ROCKERMECHANISMDESIGNAbstract:A novel methodof realizing the optimal transmissionof thecrank-and-rockermechanismispresented.Theoptimalcombinationdesignismadebyfindingtherelatedoptimaltransmissionparameters.Thediagramoftheoptimaltransmissionisdrawn.Inthediagram,therelationamongminimumtransmissionangle,thecoefficientoftravelspeedvariation,theoscillatingangleoftherockerandthelengthofthebarsisshown,concisely,convenientlyanddirectly.Themethodpossessesthemaincharacteristic.Thatitistoachievetheoptimaltransmissionparametersunderthetransmissionanglebydirectlychoosinginthediagram,accordingtothegivenrequirements.Thecharacteristicsofthemechanicaltransmissioncanbeimprovedtogaintheoptimaltransmissioneffectbythemethod.Especially,themethodissimpleandconvenientinpracticaluse.Keywords：Crank-and-rockermechanism,Optimaltransmissionangle,CoefficientoftravelspeedvariationINTRODUCTIONByconventionalmethodofthecrank-and-rockerdesign,itisverydifficulttorealizetheoptimalcombinationbetweenthevariousparametersforoptimaltransmission.Thefigure-tabledesignmethodintroducedinthispapercanhelpachievethisgoal.Withgivenconditions,wecan,byonlyconsultingthedesigningfiguresandtables,gettherelationsbetweeneveryparameterandanotherofthedesignedcrank-and-rockermechanism.Thustheoptimaltransmissioncanberealized.Theconcerneddesigningtheoryandmethod,aswellastherealcasesofitsapplicationwillbeintroducedlaterrespectively.1 ESTABLISHMENTOFDIAGRAMFOROPTIMALTRANSMISSIONDESIGNItisalwaysoneofthemostimportantindexesthatdesignerspursuetoimprovetheefficiencyandpropertyofthetransmission.Thecrank-and-rockermechanismiswidelyusedinthemechanicaltransmission.Howtoimproveworkabilityandreduceunnecessarypowerlossesisdirectlyrelatedtothecoefficientoftravelspeedvariation,theoscillatingangleoftherockerandtheratioofthecrankandrocker.Thereasonablecombinationoftheseparameterstakesanimportanteffectontheefficiencyandpropertyofthemechanism,whichmainlyindicatesintheevaluationoftheminimumtransmissionangle.Theaimrealizingtheoptimaltransmissionofthemechanismishowtofindthemaximumoftheminimumtransmissionangle.Thedesignparametersarereasonablycombinedbythemethodoflesseningconstraintsgraduallyandoptimizingseparately.Consequently,thecompleteconstraintfieldrealizingtheoptimaltransmissionisestablished.Thefollowing stepsaretakenintheusualdesignmethod.Firstly,theinitialvaluesofthelengthofrockerl3andtheoscillatingangleofrockeraregiven.ThenthevalueofthecoefficientoftravelspeedvariationKischoseninthepermittedrange.Meanwhile,thecoordinateofthefixedhingeofcrankAporealizediscalculatedcorrespondingtovalueK.1.1Lengthofbarsofcrankandrockermechanism.TheAsshowninFig.1,leftarcC2GisthepermittedfieldofpointAcoordinatesofpointA arechosenbysmallstepfrompointC2topointG.ThecoordinatesofpointA areyAyc2h0(1)xA22(2)RyAwhereh0,thestep,isincreasedbysmallincrementwithinrange(0,H).Ifthesmallerthechosenstepis,thehigherthecomputationalprecisionwillbe.R istheradiusofthedesigncircle.d isthedistancefromC2 toG.dl3cos2Rcos()l3cos(3)222CalculatingthelengthofarcAC1 andAC2,thelengthofthebarsofthemechanismcorrespondingtopointA isobtained[1,2].1.2Minimumtransmissionangle minMinimumtransmissionangle[3]min(seeFig.2)isdeterminedbytheequationscoscos

22(l42l2l3l1)min2l2l3l22l32(l4l1)2max2l2l3

(4)(5)m in 180 m ax (6)where l1——Lengthofcrank(mm)l2——Lengthofconnectingbar(mm)l3——Lengthofrocker(mm)l4——Lengthofmachineframe(mm)Firstly,wechooseminimumcomparing min with min .Andthenwerecordallvaluesof min greaterthanorequalto40 andchoosethemaximumofthem.Secondly,wefindthemaximumof min correspondingtoanyoscillatinganglewhichischosenbysmallstepinthepermittedrange(maximumofmin isdifferentoscillatingangle andthecoefficientoftravelspeedvariationK).Finally,wechangethelengthofrockerl3 bysmallstepsimilarly.Thuswemayobtainthemaximumof

min

correspondingtothedifferentlengthofbars,differentoscillatingangle

andthecoefficientoftravelspeedvariation

K

.Fig.3isaccomplishedfromTableforthepurposeofdiagramdesign.Itisworthpointingoutthatwhateverthelengthofrockerl3 isevaluated,thelocationthatthemaximumof min arisesisonlyrelatedtotheratioofthelengthofrockerandthelengthofmachineframel3/l4,whileindependentofl3.2 DESIGNMETHOD2.1RealizingtheoptimaltransmissiondesigngiventhecoefficientoftravelspeedvariationandthemaximumoscillatingangleoftherockerThedesignprocedureisasfollows.(1)AccordingtogivenKand,takenaccounttotheformulatheextremeincludedangleisfound.Thecorrespondingratioofthelengthofbarsl3/l4isobtainedconsultingFig.3.K1(7)K1801(2)Choosethelengthofrockerl3accordingtotheworkrequirement,thelengthofthemachineframeisobtainedfromtheratiol3/l4.(3)ChoosethecentreoffixedhingeDasthevertexarbitrarily,andplotanisoscelestriangle,thesideofwhichisequaltothelengthofrockerl3(seeFig.4),andC1DC2

.ThenplotC2M C1C2,drawC1N,andmakeangleC2C1N 90 .ThusthepointofintersectionofC2M andC1N isgained.Finally,drawthecircumcircleoftriangle PC1C2.(4)PlotanarcwithpointD asthecentreofthecircle,l4astheradius.ThearcintersectionsarcC2G atpoint A.Point A isjustthecentreofthefixedhingeofthecrank.Therefore,fromthelengthofthecrankl1(AC1AC2)/2(8)andthelengthoftheconnectingbarl2AC1l1(9)wewillobtainthecrankandrockermechanismconsistedofl1,l2,l3,andl4.Thustheoptimaltransmissionpropertyisrealizedundergivenconditions.2.2Realizingtheoptimaltransmissiondesigngiventhelengthoftherocker(orthelengthofthemachineframe)andthecoefficientoftravelspeedvariationWetakethefollowingsteps.(1)Theappropriateratioofthebarsl3/l4canbechosenaccordingtogivenK.Furthermore,wefindthelengthofmachineframel4(thelengthofrockerl3).(2)ThecorrespondingoscillatingangleoftherockercanbeobtainedconsultingFig.3.Andwecalculatetheextremeincludedangle .15.Then,Thenrepeat(3)and(4)insection2.13 DESIGNEXAMPLETheknownconditionsarethatthecoefficientoftravelspeedvariationK 1.1818 andmaximumoscillatingangle 40 .Thecrankandrockermechanismrealizingtheoptimaltransmissionisdesignedbythediagramsolutionmethodpresentedabove.First,withEq.(7),wecancalculatetheextremeincludedanglewefindl3/l40.93consultingFig.3accordingtothevaluesofand.Ifevaluatel350mm,thenwewillobtainl450/0.9353.76mm.Next,drawsketch(omitted).Asresult,thelengthofbarsisl116mm,l246mm,l350mm,l453.76mm.Theminimumtransmissionangleismin

l22l32(l4l12)arccos2l2l346.3698Theresultsobtainedbycomputerarel1 16.2227 mm,l2 44.5093 mm,l3 50.0000 mm,l4 53.8986 mm.ProvidedthatthefiguredesigniscarriedundertheconditionoftheAutoCADcircumstances,veryprecisedesignresultscanbeachieved.4 CONCLUSIONSAnovelapproachofdiagramsolutioncanrealizetheoptimaltransmissionofthecrank-and-rockermechanism.Themethodissimpleandconvenientinthepracticaluse.Inconventionaldesignofmechanism,taking0.1mmasthevalueofeffectivetheprecisionofthecomponentsizeswillbeenough.譯文：認識曲柄搖臂機構設計的最優(yōu)傳動方法摘要：一種曲柄搖臂機構設計的最優(yōu)傳動的方法被提出。 這種優(yōu)化組合設計被用來找出最優(yōu)的傳遞參數。得出最優(yōu)傳遞圖。在圖中，在極小的傳動角度之間 ,滑移速度變化系數，搖臂的擺動角度和桿的長度被直觀地顯示。這是這種方法擁有的主要特征。根據指定的要求，它將傳動角度之下的最優(yōu)傳動參數直接地表達在圖上。通過這種方法，機械傳動的特性能用以獲取最優(yōu)傳動效果。特別是，這種方法是簡單和實用的。關鍵字：曲柄搖臂機構 最優(yōu)傳動角度 滑移速度變化系數介紹由曲柄搖臂機構設計的常規(guī)方法,在各種各樣的參量之間很難找出優(yōu)化組合的最優(yōu)傳動。通過本文介紹的圖面設計方法可以幫助達到這個目的。在指定的情況下，通過觀查設計圖面,我們就能得到每個參量和另外一個曲柄搖臂機構設計之間的聯(lián)系。由因認識最優(yōu)傳動。具體的設計的理論和方法， 以及它們各自的應用事例將在以下介紹。優(yōu)化傳動設計的建立優(yōu)化傳動的設計一直是設計師改進傳輸效率和追求產量的最重要的索引的當中一個。曲柄搖臂機構被廣泛應用在機械傳動中。如何改進工作效率和減少多余的功率損失直接地與滑移速度變化系數，搖臂的擺動角度和曲柄搖臂的比率有關系。這些參數的合理組合采用對機械效率和產量有重要作用,這些主要體現在極小的傳輸角度上。認識機械優(yōu)化傳動目的是找到極小的傳輸角度的最大值。設計參數是適度地減少限制而且分開的合理優(yōu)化方法的結合。因此，完全限制領域的優(yōu)化傳動建立了。以下步驟被采用在通常的設計方法。首先，測量出搖臂的長度l3和搖臂的擺動角度的初始值。然后滑移速度變化系數K的值被定在允許的范圍內。同時，曲柄固定的鉸接座標A可能被認為是任意值K。1.1 曲柄搖臂機構桿的長度由圖Fig.1，左弧C2G是點A被允許的領域。點 A的座標的選擇從點 C2到點。點A的座標是yAyc2h0xAR2yA2

(1)(2)當h0，高度，在range(0，H)被逐漸增加。如果選的越小,計算精度將越高。 R是設計圓的半徑。 d是從C2到G的距離。d l3cos 2Rcos( ) l3 cos (3)2 2 2計算弧AC1和AC2的長度，機械桿對應于點 A的長度是obtained[1,2]。1.2極小的傳動角度極小的傳動角度

minmin

(參見Fig.2)由equations[3]確定coscos

l22l32(l4l1)2min2l2l322(l42l2l3l1)max2l2l3

(4)(5)min 180 m ax (6)由于l1——曲柄的長度(毫米)l2——連桿的長度（毫米）l3——搖臂的長度（毫米）l4 ——機器的長度（毫米）首先,我們比較極小值 min 和 min 。并且我們記錄所有 min 的值大于或等于，然后選擇他們之間的最大值。第二,我們發(fā)現最大值min對應于一個逐漸變小的范圍的任一個擺動的角度(最大值

min

是不同于擺動的角度和滑移速度變化系數

K)

。最后,

我們相似地慢慢縮小搖臂

l3

的長度。因而我們能獲得最大值

min

對應于桿的不同長度,另外擺動的角度

和滑移速度變化系數

K。Fig.3成功的表達設計的目的。它確定了無論是搖臂的長度

l3,最大值

min

出現的地點，只與搖臂的長度和機械的長度的比率 l3/l4有關,當確定l3時。設計方法2.1 認識最優(yōu)傳動設計下滑移速度變化系數和搖臂的最大擺動的角度設計步驟如下。(1)根據所給的K和，通常采取對發(fā)現極限角度的解釋。桿的長度的對應的比率l3/l4是從圖Fig.3獲得的。K1(7