文献翻译认识曲柄摇臂机构设计的最优传动方法.docx

文献翻译认识曲柄摇臂机构设计的最优传动方法.docx

《文献翻译认识曲柄摇臂机构设计的最优传动方法.docx》由会员分享，可在线阅读，更多相关《文献翻译认识曲柄摇臂机构设计的最优传动方法.docx（20页珍藏版）》请在冰豆网上搜索。

文献翻译认识曲柄摇臂机构设计的最优传动方法

文献翻译

英文原文：

NOVELMETHODOFREALIZINGTHEOPTIMALTRANSMISSION

OFTHECRANK-AND-ROCKERMECHANISMDESIGN

Abstract:

Anovelmethodofrealizingtheoptimaltransmissionofthecrank-and-rockermechanismispresented.Theoptimalcombinationdesignismadebyfindingtherelatedoptimaltransmissionparameters.Thediagramoftheoptimaltransmissionisdrawn.Inthediagram,therelationamongminimumtransmissionangle,thecoefficientoftravelspeedvariation,theoscillatingangleoftherockerandthelengthofthebarsisshown,concisely,convenientlyanddirectly.Themethodpossessesthemaincharacteristic.Thatitistoachievetheoptimaltransmissionparametersunderthetransmissionanglebydirectlychoosinginthediagram,accordingtothegivenrequirements.Thecharacteristicsofthemechanicaltransmissioncanbeimprovedtogaintheoptimaltransmissioneffectbythemethod.Especially,themethodissimpleandconvenientinpracticaluse.

Keywords：

Crank-and-rockermechanism,Optimaltransmissionangle,Coefficientoftravelspeedvariation

INTRODUCTION

Byconventionalmethodofthecrank-and-rockerdesign,itisverydifficulttorealizetheoptimalcombinationbetweenthevariousparametersforoptimaltransmission.Thefigure-tabledesignmethodintroducedinthispapercanhelpachievethisgoal.Withgivenconditions,wecan,byonlyconsultingthedesigningfiguresandtables,gettherelationsbetweeneveryparameterandanotherofthedesignedcrank-and-rockermechanism.Thustheoptimaltransmissioncanberealized.

Theconcerneddesigningtheoryandmethod,aswellastherealcasesofitsapplicationwillbeintroducedlaterrespectively.

1ESTABLISHMENTOFDIAGRAMFOROPTIMALTRANSMISSIONDESIGN

Itisalwaysoneofthemostimportantindexesthatdesignerspursuetoimprovetheefficiencyandpropertyofthetransmission.Thecrank-and-rockermechanismiswidelyusedinthemechanicaltransmission.Howtoimproveworkabilityandreduceunnecessarypowerlossesisdirectlyrelatedtothecoefficientoftravelspeedvariation,theoscillatingangleoftherockerandtheratioofthecrankandrocker.Thereasonablecombinationoftheseparameterstakesanimportanteffectontheefficiencyandpropertyofthemechanism,whichmainlyindicatesintheevaluationoftheminimumtransmissionangle.

Theaimrealizingtheoptimaltransmissionofthemechanismishowtofindthemaximumoftheminimumtransmissionangle.Thedesignparametersarereasonablycombinedbythemethodoflesseningconstraintsgraduallyandoptimizingseparately.Consequently,thecompleteconstraintfieldrealizingtheoptimaltransmissionisestablished.

Thefollowingstepsaretakenintheusualdesignmethod.Firstly,theinitialvaluesofthelengthofrocker

andtheoscillatingangleofrocker

aregiven.Thenthevalueofthecoefficientoftravelspeedvariation

ischoseninthepermittedrange.Meanwhile,thecoordinateofthefixedhingeofcrank

possiblyrealizediscalculatedcorrespondingtovalue

.

1.1Lengthofbarsofcrankandrockermechanism

AsshowninFig.1,leftarc

isthepermittedfieldofpoint

.Thecoordinatesofpoint

arechosenbysmallstepfrompoint

topoint

.

Thecoordinatesofpoint

are

（1）

（2）

where

thestep,isincreasedbysmallincrementwithinrange（0,

）.Ifthesmallerthechosenstepis,thehigherthecomputationalprecisionwillbe.

istheradiusofthedesigncircle.

isthedistancefrom

to

.

（3）

Calculatingthelengthofarc

and

thelengthofthebarsofthemechanismcorrespondingtopoint

isobtained[1,2].

1.2Minimumtransmissionangle

Minimumtransmissionangle

（seeFig.2）isdeterminedbytheequations[3]

（4）

（5）

（6）

where

——Lengthofcrank（mm）

——Lengthofconnectingbar（mm）

——Lengthofrocker（mm）

——Lengthofmachineframe（mm）

Firstly,wechooseminimumcomparing

with

.Andthenwerecordallvaluesof

greaterthanorequalto

andchoosethemaximumofthem.

Secondly,wefindthemaximumof

correspondingtoanyoscillatingangle

whichischosenbysmallstepinthepermittedrange（maximumof

isdifferentoscillatingangle

andthecoefficientoftravelspeedvariation

）.

Finally,wechangethelengthofrocker

bysmallstepsimilarly.Thuswemayobtainthemaximumof

correspondingtothedifferentlengthofbars,differentoscillatingangle

andthecoefficientoftravelspeedvariation

.

Fig.3isaccomplishedfromTableforthepurposeofdiagramdesign.

Itisworthpointingoutthatwhateverthelengthofrocker

isevaluated,thelocationthatthemaximumof

arisesisonlyrelatedtotheratioofthelengthofrockerandthelengthofmachineframe

/

whileindependentof

.

2DESIGNMETHOD

2.1Realizingtheoptimaltransmissiondesigngiventhecoefficientoft