xx型自卸车制动比例阀设计(毕业设计).doc

XX型自卸车制动比例阀设计(毕业设计)
13000字    26页

摘    要

众所周知，汽车制动时，如果前轮先抱死，汽车将失去转向控制能力，但尚处于在稳定状态，如果后轴先抱死，则有可能发生后轴侧滑甚至急转，使汽车失去控制，此时汽车处于非稳定状态，易发生交通事故。在汽车撞车事故中，以车轮在制动情况下抱死而引起的制动距离增加.跑偏和侧滑所引起的事故占比例最高，轿车为49.5%。轻型客货车为52.3%。为了保证汽车行驶安全，提高运输效率，世界各国都在制定或补充修订制动法规。例如，瑞典F18法规规定:在各种载荷下，在附着系数为0. 8的道路上，在低于规定的制动效能下，不能有一个车轮抱死。对总质量小于3t的汽车，在减凉度为o. 8 ~ 8. 0m /s2之间时，不允许后轮先抱死【1】。
因此加装制动里调节装置以防止后轮先于前轮抱死对汽车的安全性能有极其重要的意义。CBW3102B型自卸汽车是在原农用车基础上改装的，没有加装制动力调节装置，这对其制动的安全性和制动效率产生了巨大影响。为了提高其制动安全性和制动效率，本文拟设计一种比例阀以改善其制动安全性和制动效率。
本文是通过对该车制动力的分配计算，比较了各种比例阀的优缺点后确定并设计了一种惯性比例阀作为该车的制动力调节装置的。

关键词：防止后轮先抱死，制动力分配，计算，设计，惯性比例阀

ABSTRACT

As well as we know, while a vehicle brake, if the front wheels are locked further than the rear wheels, the vehicle will hold out to control, but he still is in stable condition; if the rear wheels are locked further than the front wheels, there may occur sideslip, even sharp turn, the vehicle is in unstable condition, it’s easy to occur an accident. In the vehicle accidents, the locking of the wheels when the vehicle is braking leads to the braking distance increase sideslip and sharp turn takes the highest proportion, car for 49.5%, light bus or vehicle for 52.3%. In order to ensure the safety of the vehicle, and improve the efficiency，all countries of the world formulated or revised brake rules and regulations. For example, the Swedish F18 regulations in various loads in a devil of 0.8 roads, below the prescribed work efficiency, can't have a locking of the wheels. For the all quality of the vehicle less than 3t, the deceleration is between o. 8 ~ 8. 0m /s2, the rear wheels locked first are not allowed.
So, it’s very important to put a braking force distribution device on the vehicle to avoid the rear wheels locked further than the front wheels. CBW3102 dumper truck is changed by the farm vehicle, hasn’t any braking force distribution device, this effect the   braking security and efficiency. So, in order to improve the braking security and efficiency this text design a proportion valve to improve the braking security and efficiency.
This text through counting the vehicle’s braking force distribution, and compare many valves’ good and bad efficiency , then decide to design the inertia proportion valve is good for this truck.

Key words：Avoid the rear wheels locked further, braking force distribution, count, design, inertia proportion valve

 
目录
中文摘要 Ⅰ
ABSTRACT Ⅱ
1绪论 1
1.1 概述 1
1.2 汽车制动力装置的发展历史 2
1.3课题研究的意义 3
1.4主要研究内容 4
2汽车前后制动力分配分析 5
2.1对该车基本数据进行分析 5
2.2比例系数C值的计算 5
2.3对该车进行理想制动力分配计算 7
3对该车应采用的实际制动力分配进行讨论分析……………………………10
3.1对该车应采用的制动力调节装置的选择 10
3.1.1限压阀 10
3.1.2比例阀 10
3.1.3感载比例阀 11
3.1.4惯性比例阀 11
3.2惯性比例阀的实际制动力分配讨论分析 12
4.惯性比例阀的设计 16
4.1惯性比例阀参数计算 16
4.2惯性比例阀尺寸参数的设计 17
4.3惯性比例阀的结构设计 18
5.结束语 21
参考文献 22