轿车自动变速器的设计说明书.doc

哈尔滨工业大学华德学院毕业设计（论文）-1-目录摘要···································································································Abstract······························································································II第1章绪论·························································································11.1自动变速器的特点及分类·····························································21.2我国自动变速器的发展现状··························································21.3设计目的··················································································41.4三速自动变速器齿轮变速系统的设计要求·······································5第2章三速自动变速器齿轮结构设计······················································62.1变速器齿轮机构工作原理·····························································62.1.1三速自动变速器齿轮变速机构···············································62.1.2各执行元件的功能·······························································62.1.3三速自动变速器齿轮变速机构···············································72.1.4变速器工作原理图·······························································82.1.5各档位工作情况分析表························································92.2自动变速器齿轮变速系统设计·······················································92.2.1三速自动变速器设计参数···················································102.2.2各档位传动比计算·····························································102.2.3最高车速计算····································································112.2.4齿轮齿数确定····································································11第3章各齿轮参数的确定及校核···························································163.1齿轮材料的选择·······································································163.2行星齿轮系统各元件的计算························································163.2.1齿圈的受力及计算·····························································163.2.2小太阳轮受力及计算··························································193.2.3大太阳轮受力及计算··························································213.2.4行星齿轮受力及计算··························································223.3离合器摩擦片的选择·································································22第4章输入轴的强度校核及轴承寿命分析···············································254.1输入轴直径的选择····································································254.1.1轴的工艺要求及材料选择···················································254.1.2轴径的初步估算································································254.2输入轴的强度校核····································································26哈尔滨工业大学华德学院毕业设计（论文）-2-4.3轴承的选择及寿命计算······························································284.3.1轴承的选择及寿命计算······················································284.3.2轴承寿命计算···································································28结论···································································································29致谢···································································································30参考文献·····························································································31附录1·································································································32附录2·································································································33摘要变速器用来改变发动机传到驱动轮上的转矩和转速，目的是在原地起步，爬坡，转弯加速等各种行驶工况下，使汽车获得不同的牵引力和速度。变速器分自动变速器和手动变速器。长期以来具有自动变速器的轿车，一直被视为高级和豪华的象征。装有自动变速器的轿车具有很多优点。装有自动变速器的轿车可以消除职业和非职业驾驶员操作上的差异。减少驾驶员的疲劳强度，提高安全性能。自动变速器可以降低发动机排放污染。但其售价昂贵，燃油经济型较差，结构复杂，维修保养困难，较难在普及型轿车上推广。本文将根据汽车燃油经济性，爬坡度等汽车性能选取最佳传动比，对其内部结构进行设计分析计算。其中是标准件的选取标准件。关键字：变速器，自动变速器，行星齿轮系统哈尔滨工业大学华德学院毕业设计（论文）-3-AbstractSpreadtothedrivingwheelusedtochangethetransmissionontheenginetorqueandspeed,thepurposeisstartinginplace,climbing,corneringspeedandotherdrivingconditions,makingthecargetdifferenttractionandspeed.Sub-transmissionautomatictransmissionandmanualtransmission.Carswithautomatictransmissionhaslongbeenseenasasymbolofhigh-levelandluxury.Carswithautomatictransmissionhasmanyadvantages.Carsequippedwithautomatictransmissionscaneliminateoccupationalandnon-professionaldriversoperatingonthedifference.Toreducedriverfatigueandimprovesafetyperformance.Automatictransmissiontoreduceengineemissions.Butthepricesaretooexpensive,poorfueleconomy,structuralcomplexity,maintenancedifficulties,difficulttobepromotedinthepopularsedan.Thiswillbebasedonvehiclefueleconomy,performanceofthecarclimbingdegreeselectthebesttransmissionratio,thedesignofitsinternalstructurecalculation.Whichisthestandardselectionofstandardparts.Keywords:transmission,automatictransmission,planetarygearsystem哈尔滨工业大学华德学院毕业设计（论文）-4-第1章绪论1.1自动变速器的特点及分类首先自动变速器取消了传统的离合器片与离合器压盘，取而代之的是液力变矩器，它的优点是通过自动变速器的油液按传递发动机传出的动力，这样即使在车辆怠速挂档后也不会熄火，而且发动机的动力平缓地传递给变速器。另外，它可以实现在前进档位下的自动变档，即根据车辆的负荷以及车速的变化增减档，减少了人为换档的劳动量，使人们在城市拥挤的交通状况下享受到轻松的驾车感受。汽车变速器是为解决发动机输出的转速和转矩与车辆驱动所需的转速和转矩间的矛盾而设立的。车辆行驶性能的好坏，不仅取决于发动机，而且在很大程度上还依赖于变速器以及变速器与发动机的匹配。目前自动变速器技术的应用，主要有以下三种形式：液力自动变速器；电控机械式自动变速器，简称；机械无级变速器。其中，液力自动变速器和机械无级变速器一样，是有级变速器的自动换档控制，而非无级变速器。液力自动变速器液力自动变速器的基本结构是由液力变矩器与动力换档的辅助变速装置组成。液力变矩器安装在发动机和变速器之间，以液压油为工作介质，起传递转矩、变矩、变速及离合的作用。液力变矩器可在一定范围内自动无级地改变转矩比和传动比，以适应行驶阻力的变化。但是由于液力变矩器变矩系数小，不能完全满足汽车使用的要求，所以，它必须与齿轮变速器组合使用，扩大传动比的变化范围。目前，绝大多数液力自动变速器都采用行星齿轮系统作为辅助变速器。行星齿轮系统主要由行星齿轮机构和执行机构组成，通过改变动力传递路线得到不同的传动比。由此可见，液力自动变速器实际上是能实现局部无级变速的有级变速器。液力自动变速器是目前使用最多的自动变速器。采用此种类型的自动变速器，免除了手动变速器繁杂的操作，使开车变得省力。同时，电子控制也使自动切换过程柔和、平顺，因此汽车具有良好的乘坐舒适性和安全性、优越的动力性和方便的操纵性。但这种变速器效率低，结构复杂，成本也较高。电控机械式自动变速器