轻型汽车悬架设计THEDESIGNOFALIGHTTRUCK`SSUSPENSION2009年6月交通大学本科毕业设计(论文)第Ⅳ页摘要本文主要研究轻型货车的前后悬架设计分析方法,以及悬架运动与前轮定位参数的变化关系。首先根据设计给定的四个参数对整车进行总体设计,包括整车的尺寸参数、质量参数和性能参数,在选择这些参数的时候可以通过国家标准以及相关的经验参数得到,在选择之后进行了相关的验证,保证各参数能达到各项性能的基本要求。在总体设计完成之后,对前后悬架进行方案的选择,本设计前悬架采用麦弗逊独立悬架,后悬架采用纵置钢板弹簧。然后对悬架的性能参数进行选择,包括前后悬架的偏频、相对阻尼系数、非簧载质量以及影响操稳性的侧倾中心高度和侧倾刚度,还有影响纵向稳定性的纵倾中心高度等。在选择完基本参数后,对悬架的弹性元件(前悬架为螺旋弹簧。后悬架为钢板弹簧)进行设计计算,包括刚度和强度等的校核,使设计的弹簧能满足设计的偏频要求。之后设计前独立悬架的导向机构,设计包括侧倾中心、纵倾中心以及下控制臂的位置等。为前、后悬架匹配减振器,计算减振器的尺寸,并且验算减振器是否满足强度要求。由于麦弗逊悬架的侧倾刚度较小,为了满足汽车不足转向性能要求,设计时,为前悬架匹配了一个横向稳定杆,提高它的侧倾刚度,满足不足转向性能要求。由于悬架结构的运动学特性关系到汽车操纵稳定性、转向轻便性、行驶舒适性、轮胎寿命以及汽车布置设计中的运动干涉等诸多方面,是汽车设计过程中十分重要的问题,欲设计合乎需要的悬架结构,必须准确分析悬架结构的运动特性。所以为了研究悬架结构的运动学特性,本文采用了空间解析几何的方法,探讨分析了麦弗逊式悬架的运动学特性,由于该方法能够直接使用整车布置设计坐标系,无需进行坐标转换,且直观方便,易于理解,所以具有实际应用的意义。关键词:麦弗逊悬架动态特性交通大学本科毕业设计(论文)第V页AbstractThisarticleismainlyabouttostudythemethodofdesigningalighttruck’sfrontandbacksuspension,alsothearticleanalyzetherelationbetweensuspensionmovementandfrontwheelalignmentparameters.First,itdesignstheschemeofwholecarbasedonthefourparameterswhichwasalreadybeengiven,thisincludingthewholecar’ssizeparameters,weightparameters,andpropertyparameters.wemaychoosethoseparametersrefertonationalstandardsorsomerelativeexperienceparameters.wemayalsodosomeworktoprovethechosenwascorrectafterthoseparametersbeingchosen,astomakeeveryparametersmeetthebasicdemandofeveryproperty.whenthewholecarschemeswerealreadydesigned,itthencomestochoosetheschemeofthefrontandbacksuspensions,andinthisdesign,weuseMcPhersontypefrontsuspension,Backsuspension’ssteelspings.andthen,wechoosethesuspension’spropertyparemeters,includingfrontandbacksuspension’sfrequency,relativeviscosity,unsprungmassandrollcenterheight,rollangularrigiditywhicheffectthecar’scontrollabilityandstability,besides,wealsochoosethetrimcenterheightwhicheffectthecar’slongitudinalcontrollability.Afterthesebasicparameterswerechosen,wecomesontocalculatethespringofthesuspension,(spiralspringinfrontsuspension,leafspringinbacksuspension),andthecalculationincludingcheckingboththesprings`stiffnessandstrength,astomakethespringdesignedtomeetthedemandoffrequency.Andnextcomestodesignthecontrolbarsofthefrontindependentsuspension,itcontainstodesigntherollcenterheightantrimcenterheightandthelocationsofthemaincontrolbar.Then,wedesignshockabsorberstomatchwiththefrontandthebacksuspension,includingcalculatethesizeoftheabsorbersandalsochecktheabsorberstoseeifitmeetsthedemandofstrength.SinceMcPhersontypefrontsuspensionislackofrollangularrigidity,inordertomeetthepropertydemandsofcar’sundersteerspeciality,Hereitalsodesignsaanti-rollbartoimprovethefrontsuspension’srollangularrigidity.Assuspension’skinematicscharacterrelatestoawholecar’scontrollability,steeringagility,ridecomfort,tyrelifeandmotioninterferenceinthedesignofthewholecar’sscheme.thekinematicscharactercomestobeaveryimportantquestion,tomakeagood交通大学本科毕业设计(论文)第VI页suspensionstructrue,itneedstoanalyzethekinematicscharacterofthesuspension.Andinthisarticle,weusesSpatialanalyticgeometrytodiscussMcPhersontypefrontsuspension’skinematicscharacter.Becausethemethodisabletousethewholecarschemedesigncoordinatesystemdirectly,thereisnoneedtotransformthecoordinatesystem.Itismoreconvenientandeasytounderstand,so,itmakesmoreactualapplicationsense.keywords:Mcphersonsuspensionkinematicscharacter交通大学本科毕业设计(论文)第VII页目录第1章绪论.........................................................................................................................11.1论文研究的目的和意义.........................................................................................11.2国内外研究现状及发展趋势.................................................................................11.3论文主要研究内容.................................................................................................2第2章汽车的总体设计.....................................................................................................32.1设计参数与设计目标..............................................................................................32.2汽车形式的选择......................................................................................................32.2.1轴数...............................................................................................................32.2.2驱动形式.......................................................................................................32.2.3布置形式.......................................................................................................42.3汽车质量参数的选择..............................................................................................42.3.1整车整备质量...............................................................................................42.3.2汽车的总质量...............................................................................................52.3.3汽车的整备质量利用系数0m.....................................................................52.3.4汽车的轴荷分配...........................................................................................62.4汽车主要尺寸的确定...............................................................
本文标题:汽车悬架设计论文
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