机械类外文文献翻译Word文档格式.docx
- 文档编号:13767497
- 上传时间:2022-10-13
- 格式:DOCX
- 页数:13
- 大小:616.38KB
机械类外文文献翻译Word文档格式.docx
《机械类外文文献翻译Word文档格式.docx》由会员分享,可在线阅读,更多相关《机械类外文文献翻译Word文档格式.docx(13页珍藏版)》请在冰豆网上搜索。
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,theinitialvaluesofthelengthofrockerandtheoscillatingangleofrockeraregiven.Thenthevalueofthecoefficientoftravelspeedvariationischoseninthepermittedrange.Meanwhile,thecoordinateofthefixedhingeofcrankpossiblyrealizediscalculatedcorrespondingtovalue.
1.1Lengthofbarsofcrankandrockermechanism
AsshowninFig.1,leftarcisthepermittedfieldofpoint.Thecoordinatesofpointarechosenbysmallstepfrompointtopoint.
Thecoordinatesofpointare
(1)
(2)
where,thestep,isincreasedbysmallincrementwithinrange(0,).Ifthesmallerthechosenstepis,thehigherthecomputationalprecisionwillbe.istheradiusofthedesigncircle.isthedistancefromto.
(3)
Calculatingthelengthofarcand,thelengthofthebarsofthemechanismcorrespondingtopointisobtained[1,2].
1.2Minimumtransmissionangle
Minimumtransmissionangle(seeFig.2)isdeterminedbytheequations[3]
(4)
(5)
(6)
where——Lengthofcrank(mm)
——Lengthofconnectingbar(mm)
——Lengthofrocker(mm)
——Lengthofmachineframe(mm)
Firstly,wechooseminimumcomparingwith.Andthenwerecordallvaluesofgreaterthanorequaltoandchoosethemaximumofthem.
Secondly,wefindthemaximumofcorrespondingtoanyoscillatinganglewhichischosenbysmallstepinthepermittedrange(maximumofisdifferentoscillatingangleandthecoefficientoftravelspeedvariation).
Finally,wechangethelengthofrockerbysmallstepsimilarly.Thuswemayobtainthemaximumofcorrespondingtothedifferentlengthofbars,differentoscillatingangleandthecoefficientoftravelspeedvariation.
Fig.3isaccomplishedfromTableforthepurposeofdiagramdesign.
Itisworthpointingoutthatwhateverthelengthofrockerisevaluated,thelocationthatthemaximumofarisesisonlyrelatedtotheratioofthelengthofrockerandthelengthofmachineframe/,whileindependentof.
2DESIGNMETHOD
2.1Realizingtheoptimaltransmissiondesigngiventhecoefficientoftravelspeedvariationandthemaximumoscillatingangleoftherocker
Thedesignprocedureisasfol
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 机械类 外文 文献 翻译