论文曲轴偏置在增强发动机扭矩和功率方面的研究

…………………….……………山东农业大学毕业论文曲轴偏置在增强发动机扭矩和功率方面的研究院部专业班级届次学生姓名学号指导教师二О一一年六月十日装订线……………….…….………….………i目录摘要..................................................................IAbstract.............................................................II引言..................................................................11曲柄连杆机构的运动学分析.............................................11.1中心曲柄连杆机构运动学分析......................................21.2曲轴偏置式曲柄连杆机构的运动学分析..............................31.3直列式中心曲轴连杆机构的缺点分析................................41.3.1死点位置布置不合适..........................................41.3.2活塞运动时最高点和最低点与死点重合.........................41.4曲轴偏置对发动机的影响..........................................51.4.1曲轴偏置对发动机各机构运动的影响............................51.4.2曲轴偏置对发动机四个行程的影响..............................51.4.3曲轴偏置对发动机燃烧效率、平均有效压力和充气效率的影响......62曲轴偏置式曲柄连杆机构上的作用力分析................................72.1直列式曲柄连杆机构的作用力分析..................................72.2直列式曲轴正置发动机传动效率分析................................92.3曲轴偏置式曲柄连杆机构的作用力分析.............................122.4中心和偏置式发动机传动效率对比分析.............................143曲柄偏置量的计算方法................................................153.1方法一：用最大传动效率时的曲轴偏置量............................153.2检验方法一的实用性.............................................163.3方法二采用40°压力角的曲轴偏置量计算方法......................174曲轴偏置式发动机作用力分析.........................................194.1切向力分析.....................................................194.2侧向力分析.....................................................205结束语.............................................................21参考文献.............................................................21致谢.................................................................22iiContentsAbstract...............................................................................................................................iiIntroduction………………………………………………………………………………11Kinematicsanalysisofcrankrodsystem.........................................................................21.1Kinematicsanalysisofcentercrankrodsystem.......................................................21.2Kinematicsanalysisofcrankshaftoffsettypeofcrankrodsystem..........................31.3Inlinetypecenterofcrankshaftlinkagemechanismanalysisandshortcomings......41.3.1Deadspotsarrangementinappropriateposition.................................................41.3.2Pistonmotionwithhighandlowcoinsidedeadspots.....................................41.4Theimpactofenginecrankshaftoffset...................................................................51.4.1Theinfluenceofenginecrankshaftoffsetvariousagenciesmovement.............51.4.2Theimpactofcrankshaftoffsetfourstrokeengines..........................................51.4.3Theinfluenceofcrankshaftbiasonenginecombustionefficiency,averageeffectivestressandthechargingefficiency.......................................................62Thecrankshaftoffsettypeofcrankrodsystemforceanalysis.........................................62.1Inlinetypeofcrankrodsystemforceanalysis..........................................................62.2Inlinetypecrankshaftisbuyenginestransmissionefficiencyanalysis....................92.3Crankshaftoffsettypeofcrankrodsystemforceanalysis.....................................112.4Centerandoffsettypeenginetransmissionefficiencycomparativeanalysis.........133Crankoffsetcalculationmethods...................................................................................133.1Method1:Withmaximumtransmissionefficiencyofthecrankshaftoffset..........133.2Thepracticabilityofinspectionmethodone..........................................................143.3Method2:By40°ofpressureAnglecrankshaftoffsetcalculationmethod...........164Thecrankshaftoffsettypeengineforceanalysis……………………………………...184.1Tangentialforceanalysis.......................................................................................184.2Lateralforceanalysis.............................................................................................195Conclusion.....................................................................................................................20References……………………………………………………………………………….22Acknowledgement………………………………………………………………………22I曲轴偏置在增强发动机扭矩和功率的研究作者：指导教师：（讲师）【摘要】本文主要研究了曲轴偏置在发动机上的应用及对发动机扭矩和功率的影响。曲轴偏置主要应用到发动机的设计改进方面，可以将运动死点位置移开使之不与上下止点重合；可以有效的利用曲柄滑块机构的急回特性，增大做工行程曲轴转角，减小排气行程曲轴转角。主要在理论上分析了在燃烧室爆发最大压力时确保较大传动效率的的合理偏置距离和偏置率。并检验在这种情况下发动机的切向力和侧向力，以确保发动机的稳定性。该技术并未得到应有的足够重视，对这方面的研究不是很多，相信以后随着发动机技术的进一步发展，曲轴偏置会去的长足发展。关键词：曲轴偏置;发动机;扭矩;功率IIThestudyofcrankshaftinenhancementenginetorqueandpowerAuthor:Supervisor:（lecturer）AbstractThispapermainlystudiesthecrankshaftbiasintheapplicationoftheengineandenginetorqueandpowerinfluence.Thecrankshaftbiasmainlyappliedtothedesignoftheengine,canimprovethesportsdeadspotstonoopenpositionandfluctuationcheckpointcoincidence;Canimprovethetransmissionefficiencyandreducetheheightoftheengine;Cantheeffectiveutilizationofslider-crankmechanismisurgent,increasethetripbacktocharacteristicsofthecrankshaftw