车辆工程毕业设计44福克斯2.0轿车变速器的设计

本科学生毕业设计

福克斯2.0轿车变速器的设计

系部名称： 汽车与交通工程学院 专业班级： 车辆工程 学生姓名： 指导教师： 职 称： 讲师

The Graduation Thesis for Bachelor's Degree

Design on transmission of fox 2.0 car

Candidate：Liu Lu

Specialty：Vehicle engineering Class：B07-8

Supervisor：lecturer . Li Rong

Heilongjiang Institute of Technology

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，同时使发动机在最有利的工况范围内工作。变速器设有空挡，可在起动发动机、汽车滑行或停车时使发动机的动力停止向驱动轮传输。变速器设有倒挡，使汽车获得倒退行驶能力。需要时，变速器还有动力输出功能。

本次设计任务是设计一款用于中型轿车的前置后驱式机械式五挡变速器。手动变速器具有结构简单、效率高、功率大、制造成本低等显著优点，所以在中国乘用车市场一直占据着汽车变速器的主导地位。本次设计拟采用中间轴式变速器，其显著优点是直接挡利用率较高，在其他前进挡位工作时一挡仍然有较大的传动比。但在其他前进挡位工作时其传动效率略有降低，同时由于其操作复杂，会使驾驶员产生疲劳感，噪声较大，这是它的缺点。

首先要选择发动机型号，确定发动机的最大功率、最大扭矩、最高转速等重要参数，然后根据上述参数选择最大及最小传动比，合理分配各挡传动比。结合运用汽车设计、汽车理论、机械设计、机械原理等知识，计算出变速器各个齿轮及轴的参数并校核其强度，论证设计方案的合理性，最后要画出变速器齿轮和轴的零件图。

关键词：变速器；传动比；齿轮；轴；计算；校核

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ABSTRACT

The transmission gearbox is used to change torque and the rotate speed from engine to driving gear, In-situ start, the hill climbing, the curve, the acceleration and so on under each kind of travel operating mode, the goal is to obtain the different force of traction and the speed, meanwhile makes the engine to work in the most advantageous operating mode scope.The transmission gearbox is equipped with the neutral which can stop the power from the engine to the driving gear transmission when starting engine, the automobile glide or parking,The transmission gearbox is equipped with the reverse gear, makes the automobile to obtain reversing travel ability.When needed, the transmission gearbox also has the dynamic output function.

The task is to design one five-gear manual transmission used in the front engine rear drive intermediate.The manual transmission gearbox has many advantages including simple structure, high efficiency, big power, low production cost, therefore which is always occupying the automobile transmission gearbox dominant position in vehicle market of China.This design plans to use the middle shaft-type transmission gearbox which has the merit of high efficiency in the positive gear,and when working in the other forward gears position still has the great velocity ratio,but reduces the transmission efficiency, because of its complicated operation, it can make the pilot to have the weary feeling, the big noise, this is its shortcoming.

First we must choose the engine type, gain the maximum power, the maximum torque, the highest rotate speed, the important parameter and so on , then according to above parameter choose the biggest and the smallest velocity ratio, distribute all the velocity ratio rational.Using the knowledge about automobile design, automobile theory, machine design, mechanism and so on, we can calculate the parameter of each gear and the axis and examine its intensity, prove the paper’s rationality, finally must draw the part drawing of an gear and an axis.

Key words: Transmission；Transmission Ratio；Gear ；Shaft；Calculation；Check

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