河南科技大学毕业设计（论文）题目柴油动力SUV车设计----后驱动桥、后悬架设计姓名院系车辆与动力工程学院专业车辆工程指导教师柴油SUV后驱动桥与后悬架的设计摘要车桥有两种基本形式：非断开式和断开式。
非断开式车桥不转动，而车轮在车桥上转动。
最常见的例子就是在马车上所见到的非断开式车桥。
断开式车桥与车轮相连接，这样两者一起转动。
断开式车桥根据其承载方式可分为：半浮式，四分之三浮式和全浮式。
后桥与车轮相连，内端装有一个半轴齿轮。
差速器壳支撑在左侧车桥上，而且能够在轴承上做独立转动。
差速器壳支承在行星齿轮轴上，行星齿轮与两个半轴齿轮相啮合。
冠状齿轮与差速器壳相连接，这样当冠状齿轮由传动齿轮驱动转动时，差速器壳也转动。
也就是说，驱动力是从传动轴末端的传动齿轮输送到差速器的。
当汽车直线行驶时，两个行星齿轮不在齿轮轴上转动，但却向两个半轴齿轮传递动力，这样半轴齿轮与冠状齿轮的转速相等。
从而使两个后轮也以同样的速度转动。
当汽车转弯时，外侧车轮就必须比内侧车轮转的更快。
为了达到这一目的，两个行星齿轮在齿轮轴上传动，给外侧的车轮提供比内侧的车轮更多的运动，这样外侧车轮轴上的半轴齿轮比内侧车轮轴上的半轴齿轮转动的更快。
目前使用的悬挂系统基本上为两种，一种是整体桥与刚板弹簧组成的非独立悬架，另一种是使用长短摆臂的独立悬架。
这些悬挂系统有各种不同的搭配，但是均运用相同的工作原理。
非独立悬挂使用整体式车桥，两侧用钢板弹簧连接。
通过装在轮轴和车桥之间的驱动轴，两端的车轮可以转动。
使用独立悬架，每个车轮都可以自由的上下运动，几乎不受另一车轮的影响。
关键词：车桥，行星齿轮，半轴齿轮，非独立悬架，独立悬架，钢板弹簧DIESEL-POWERED SUV DESIGNREAR AXELS AND SUSPENSIONABSTRACTThere are two basic tyes of axle:dead axleds and live axle.The dead axle does not rotate:the wheel rotates on it .A common example is the axle on a horse –drawn wagon.Live axles are attached to the wheel so that both the wheel and the axle rotatetogether.Live axles are classified accorading to manner in which they are supported:semifloating,three-quarter-floaring,and full-floating.The rear axles are attached to the wheels and have bevel side gears on their inner ends.The differential case isassembled on the left axle but can rotate on a bearing independently of the axle.The differential case supports the differdntial-pinion gear on a shaft,and this gear meshs with the two bevel gears.The ring gear is attched to the differential case so that the case rotates with the ring gear when the latter is driven by the drive pinpion.The driving power enters the diffential throuth the drive pinpion on the end of the ropeller shaft.When the car is on a straight road ,the two differential-pinion gears do not rotate on the pinion shaft ,but they do exert pressure on the side gear,causing both rear wheels to turn at the same speed ,also.When the car rounds a curve ,the outer wheel must turn faster than the inner wheel.To permit this,the two pinion gears rotate on their pinion shaft,transmitting more turning movement to the outer side gear than to the inner side gear.Thus the side gear on the outer-wheel axle turns more rapidly than the side gear on the inner-wheel axle .There are two basic suspension systems is use today.One is the solid axle,leaf spring type;the other is the independent suspension using long and short swing arms.There are various sdaptations of these systenms,but all use the same basic principle.The solid axle suspension uses a solid steel dead axle with a leaf spring at each side.The wheels swivel on each end via a pivot arrangment between the axle and the wheel spindle.With independent suspension,each wheel is free to move up and down with minimum effect on the other wheel.Key word: Rear axles,differential-pinion gear,bevel side fears,solid axle,independent suspension,leaf spring.符号说明: 车轮的滚动发半径rr: 最大功率时发动机的转速np: 最高车速vamax: 变速器最高档传动比igHT: 发机最大转矩emaxN: 驱动桥数目i: 由发动机至所计算的主减速器从动齿轮之间的传系最档传动比TLηT：上述传动部分传动效率：离合器产生冲击载荷时超载系数K: 满载时一个驱动轮上的静载荷系数G2ø: 轮胎与路面间的附着系数r: 车轮的滚动半径rηlB i lB：分别为所计算的主减速器从动齿轮到驱动车轮之间的传动效率和传动比p：单位齿长上的圆周力 N/mm：变速器Ⅰ档传动比ig：主动齿轮节圆直径d1F：动齿轮的齿面宽τ: 半轴的扭转应力T ：半轴的计算转矩d：半轴杆部直径K ：超载系数：尺寸系数，反映材料性质的不均匀性，与齿轮尺寸及热处理等有关。
