轿车变速器设计说明书

长春理工大学本科毕业设计I摘要本设计的任务是设计一台用于轿车上的FR式的手动变速器。本设计采用中间轴式变速器，该变速器具有两个突出的优点：一是其直接档的传动效率高，磨损及噪声也最小；二是在齿轮中心距较小的情况下仍然可以获得较大的一档传动比。根据轿车的外形、轮距、轴距、最小离地间隙、最小转弯半径、车辆重量、满载重量以及最高车速等参数结合自己选择的适合于该轿车的发动机型号可以得出发动机的最大功率、最大扭矩、排量等重要的参数。再结合某些轿车的基本参数，选择适当的主减速比。根据上述参数，再结合汽车设计、汽车理论、机械设计等相关知识，计算出相关的变速器参数并论证设计的合理性。它功用是：①改变传动比，扩大驱动轮转矩和转速的变化范围，以适应经常变化的行驶条件，如起步、加速、上坡等，同时使发动机在有利的工况下工作；②在发动机旋转方向不变的前提下，使汽车能倒退行驶；③利用空档，中断动力传递，以使发动机能够起动、怠速，并便于发动机换档或进行动力输出。这台变速器具有五个前进档（包括一个超速档五档）和一个倒档，并通过锁环式同步器来实现换档。关键词：变速器，锁环式同步器，传动比，中间轴，第二轴，齿轮长春理工大学本科毕业设计IIAbstractThedutyofthisdesignistodesignaFRtypemanualtransmissionusedinthesaloon,It’sthecountershaft-typetransmissiongearbox.Thistransmissionhastwoprominentmerits:Firstly,thetransmissionefficiencyofthedirectdrivekeepsoffhigh,theattritionandthenoisearealsoslightest;Secondly,it’sallowedtoobtaininthebigergearratioofthefirstgearwhenthecenterdistanceissmaller.Accordingtothecontour,track，wheelbase，thesmallestgroundclearance,thesmallestturningradium,thevehiclesweight,theall-upweightaswellasthehighestspeedandsoon,unionthechoosingenginemodelwecanobtaintheimportantparametersofthemaxpower,themaxtorque,thedisplacementandsoon.Accordingtothebasicparametersofthecertainsaloon,choosethesuitablefinaldriveratio.Accordingtotheaboveparameters,combiningtheknowledgeofautomobiledesign,automobiletheory,machinedesignandsoon,calculatethecorrelatedparametersofthegearboxandprooftherationalityofthedesign.Itsfunctionis:①Changinggearratio,expandingthetorqueofthedrivingwheelandtherangeoftherotationalspeed,toadaptthetravelconditionwhichfrequentlychanges,likestart,acceleration,climbingandsoon,simultaneouslycausestheenginetoworkundertheadvantageousoperatingmode;②Underthepremiseoftheinvariablerotation,enablestheautomobiletotravelback;③Usingneutral,severancesthepowertransmission,tomaketheenginestart,idle,andisadvantageousfortheenginetoshiftgearsortocarryonthedynamicoutput.Thisgearboxhasfive(includingoverdrive—fifthgear)andareversegear,andthroughtheinertialtypeofsynchronizertorealizeshiftgears.Keyword：transmission,inertialtypeofsynchronizer,gearratio,countershaft,secondaxis,gear长春理工大学本科毕业设计目录摘要..............................................................................................................................IAbstract.........................................................................................................................II第1章变速器的概述..................................................................................................11.1变速器功用及设计要求.................................................................................11.1.1汽车变速器的功用................................................................................11.1.2变速器的设计要求................................................................................11.2设计任务及主要数据.....................................................................................2第2章变速器的选择及主要零件设计......................................................................32.1变速器的选择.................................................................................................32.1.1两轴式变速器与三轴式变速器.............................................................32.2倒档传递方案.................................................................................................52.3变速器主要零件的分析.................................................................................62.3.1齿轮型式................................................................................................62.3.2换挡结构形式........................................................................................72.4轴承形式.........................................................................................................72.5传动方案的最终设计.....................................................................................8第3章变速器传动机构的计算..................................................................................93.1变速器主要参数的选择.................................................................................93.1.1档位数的确定及传动比初选................................................................93.1.2中心距的确定........................................................................................93.1.3传动零件的设计....................................................................................93.1.4齿轮材料、压力角α、螺旋角β和齿宽b.......................................103.1.5各档齿轮参数的确定..........................................................................113.2变速器齿轮的强度计算...............................................................................143.2.1齿轮的损坏原因及形式......................................................................143.2.2齿轮的强度计算与校核......................................................................143.2.3齿轮接触强度的校核..........................................................................16第4章变速器轴的强度计算与校核........................................................................184.1变速器轴的结构和尺....................................................................................184.1.1轴的结构..............................................................................................1