(完整版)金龙6800中型客车气压制动系统改进设计说明书毕业设计论文.doc

1、优秀论文未经允许审核通过切勿外传摘 要本次设计主要是对中型客车制动系统结构进行分析的基础上，根据对中型客车制动系统的要求，设计出合理的符合国家标准和行业标准的制动系统。首先制定出制动系统的结构方案设计计算确定前盘、后鼓式制动器。绘制出了前、后制动器装配图、制动阀装配图、制动管路布置图。最终对设计出的制动系统的各项指标进行评价分析。通过本次设计的计算结果表明设计出的制动系统是合理的、符合标准的。其满足结构简单、成本低、工作可靠等要求。关键词： 中型客车；制动系统设计；盘式制动器；鼓式制动器；气压系统；AbstractBased on the structural analysis and the

2、 design requirements of n.medium bus braking system, a braking system design is performed in this thesis, according to the national and professional standards.The braking system design starts from determination of the structure scheme. Calculating and determining the main dimension and structural ty

3、pe of thefront disc、 drum brake， brake master cylinder，and therefore draw the engineering drawings of the front and rear brakes, Brake valve, the diagram of the brake pipelines.The results show the design of braking system is reasonable, consistent with the standards and satisfies the requests such

4、as simple structure and low cost.Key words: Medium-sized passenger car; braking system design; disc brake; drum brake; pneumatic system;目录第 1 章 绪 论 .11.1制动器设计的意义及目的 .11.2汽车制动系统设计的要求 .11.3汽车制动系统的组成 .11.4制动系工作原理 .21.5制动器研究现状 .3第 2 章 汽车制动方案论证分析与选择 .52.1制动器形式方案分析 .52.1.1鼓式制动器结构形式 .52.1.2盘式制动器结构形式 . .72.

5、2制动驱动机构的结构型式与选择 .92.2.1简单制动系 .92.2.2动力制动系 .102.2.3伺服制动系 .102.3液压分路系统的形式与选择 .11第 3 章 制动系统主要参数的确定 . .133.1中型客车主要技术参数 .133.2同步附着系数的的确定 .133.3前、后轮制动力分配系数的确定。 .143.4盘式制动器主要参数的确定 .143.5制动器最大制动力的确定 .153.6盘式制动器制动因数计算 .153.7鼓式制动器的设计计算 .163.8鼓式制动效能因素计算 .163.9制动器的温升计算 .173.10盘式制动器主要零部件的结构设计 .183.11鼓式制动器主要零部件的结

6、构设计 .19第 4 章 气压制动系统结构设计与分析 .214.1气压制动系统结构 .214.1.1气压制动回路 .214.1.2供能装置 .214.1.3控制装置 .224.1.4制动气室 .244.2气压驱动机构的设计与计算 .254.2.1制动气室设计 .254.2.2贮气筒 .264.2.3空气压缩机的选择 .26第 5 章 制动性能评价分析 . .275.1制动性能评价指标 .275.2制动效能 .27282829.29.30.3031323334395.3制动效能的恒定性 .5.4制动时汽车的方向稳定性 .5.5前、后制动器制动力分配 .5.5.1地面对前、后车轮的法向反作用力5.

7、5.2理想的前、后制动器制动力分配曲线5.5.3实际的前、后制动器制动力分配曲线第 6 章 总 论 .参考文献 .致谢 .附 录 1 .附 录 2 .第1章绪论1.1 制动器设计的意义及目的汽车制动系统是汽车最重要的系统之一，它是制约汽车运动的装置。而制动器又是制动系中直接作用制约汽车运动的一个关键装置，直接影响汽车的安全性。随着高速公路的迅速发展和车流密度的日益增大，交通事故也不断增加。在汽车交通事故中，除去违章驾驶以外，最主要原因就是车辆机械故障，而在各种交通故障中制动失灵占有相当高的比例。中型客车的载客量比较大，对中型客车的制动性能要求更加严格，因此这次中型客车气压制动系统改进设计对提高

8、汽车制动性能有这重要的实际与理论意义。制动器设计的目的：1、通过查阅相关的资料，运用专业基础理论和专业知识，确定中型客车制动系统的设计方案，进行部件的设计计算和结构设计。2、达到综合运用所学知识分析汽车基本性能和部件设计的训练，为今后实际工作打下基础。1.2汽车制动系统设计的要求1、保证客车具有足够的制动效能，客车在30km and Safety (SecondEdition). Warren dale, PA, USA: SAE, Inc., 1999致谢论文的完成标志着我的学业即将告一个段落，值此论文完成之际，谨向我的老师张立军教授表示最衷心的感谢！首先，感谢我的导师张立军教授，从论文的选

9、题、确定、提纲、修改直至完成，始终得到了张立军老师的悉心指导。其渊博的学识和严谨治学态度令人敬佩；他所具有的高尚品德和不断探索的精神令人敬重。其次，感谢我读本科期间的各位任课老师，在他们的教导下，我的学识水平才得以提高，论文研究才能顺利完成；他们的谆谆教诲将使我受益终生。在学习生活和论文研究期间， 我得到了许多同学的无私帮助和鼓励， 他们提供了许多研究资料并提出了许多宝贵意见和建议。同窗之谊，我终生难忘。感谢和他们一起渡过了我令我难忘的时光。感谢汽车与交通工程学院所有对我的学习和工作给予支持和帮助的老师。感谢我在实习期间的所有帮助过我的同事和领导，感谢他们传授给我他们丰富的工作经验，让我受益匪

10、浅 .最后我要特别感谢我的父母、姐姐和全家亲人，感谢他们一直以来对我在生活上的关心和精神上的支持， 我的每一点进步都离不开他们的鼓励。感谢所有关心我的人，在此表达我对他们最诚挚的谢意。谢谢所有给予我帮助的人们！附 录 1BRAKE SYSTEMThe braking system is the most important system in cars. If the brakesfail, the result can be disastrous.Brakes are actually energy conversion devices, which convert the kinetic

11、energy (momentum) of the vehicle into thermal energy (.The typical brake system consistsof disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and the brake pedal, a plunger is actually been pushing against in the master cylinder which forces be directed th

12、rough many twists and turns on itsway to its destination, arriving with the exact same motion and pressure that it started with. It is very important that the fluid is pure liquid and that there are no air bubbles in it. Air can compress, which causes a sponginessto the pedal and severely reduced br

13、aking efficiency. If air is suspected,then the system must be bled to remove the air. There are“ bleeder screws ” at each wheel cylinder and caliper for this purpose.With drum brakes, fluid is forced into the wheel cylinder which pushes the brake shoes out so that the friction linings are pressed ag

14、ainst the drum which is attached to the wheel, causing the wheel to stop.On a disk brake, the fluid from the master cylinder is forced into a caliper where it presses against a piston. The piston, in-turn, squeezes two brake pads against the disk(rotor)which is attached to the wheel, forcing it to s

15、low down or stop. This process is similar to a bicycle brake where two rubber pads rub against the wheel rim creating friction.In either case, the friction surfaces of the pads on a disk brake system,or the shoeson a drum brake convert the forward motion of the vehicle into surfaces (linings) of the

16、 pads and shoes to eventuallywear out and require replacement.Drum BrakesSo if disk brakes are so great, is cost. While all vehicles produced formany years the front, drum brakes are cheaper to produce for the rear wheels. The main reason is the parking brake system. On drum brakes, adding a parking

17、 brake is the simple addition of a lever, while on disk brakes, we need a complete mechanism, in some cases, a complete mechanical drum brake assembly inside the disk brake rotor! Parking brakes must be a separate system that does not useparking brakes laterWheel CylinderThe wheel cylinder consists

18、of a cylinder that each side. Each piston with a brake shoe. When brake pressure is applied, the pistons are forced out pushing the shoes into contact with the drum. Wheel cylinders must be rebuilt or replaced if they show signs of leaking.Brake ShoesLike the disk pads, brake shoesconsistof a steel

19、shoe with the friction material or lining riveted or bonded to it. Also like disk pads, the linings eventuallywear out and must be replaced. If the linings are allowed to wear through to the bare metal shoe, they will cause severe damage to the brake drum.Backing PlateThe backing plate is whatvirtua

20、lly every car made. On most cars,the front brake are of the disc type, and the rear brakes are of the“ drum”type. Drum brakes use two semi-circular shoesto press outward against the inner surfaces of a steel drum. Older cars often all four wheels, andmany new the same basic principles to slow a vehi

21、cle (friction andis far superior to that of drum brakes. Becausedisc brakes can fling off water more easily than drum brakes, they work much better in wet conditions. This is not to say that water does not affect them, it definitely does. If you splash through a puddle and then try to apply the brak

22、es, your brakes may not work at all for a few seconds！Disc brakes also allow better airflow cooling, which also increasestheir effectiveness.Some most cars in the early seventies.译 文制动系统制动系统是汽车中主要的系统之一。 如果制动损坏， 结果可能是惨重的。制动器是能量转换装置， 它将汽车的动能 （动量）转化成热能（热量）。制动系统是由下列基本的成分组成 : “制动主缸” “制动管路” “制动软管”“制动轮缸” “

23、制动盘”和“衬块”等等。典型的制动系统布置有前后盘式，前盘后鼓式，各个车轮上的制动器通过一套管路系统连接到制动主缸上。踩着制动踏板时，事实上是制动主缸中的活塞通过一连串的管路和软管强制液压油（制动液）推入到每个轮子上。 因为液压油液 ( 或任何的流动性的物质而言 ) 不能够被压缩 , 推动液体经过一个管路就像推动一个钢筋通过一个管路。然尔，与钢筋不同的是液体可以直接通过许多弯曲的地方并可以任意改变方向，像它开始的那样以相同的精确的压力和运动到达某个地方。非常重要的是， 液体是纯粹的液体而且没有空气泡沫在它里面。当空气被压缩， 引起制动踏板的迟疑， 并减少制动效率。 如果怀疑有空气，那么系统就会

24、放出空气，每个车轮上的放气螺钉和卡钳就是这个目的。在盘式制动器中， 主缸中的液体被迫压缩到活塞中。 活塞作往复运动，挤压这两个制动块和连接着车轮的制动蹄。 这个过程类似于自行车的刹车，自行车的两个橡胶板作用在车轮上制造摩擦。鼓式制动器，流体是被迫进入轮缸，推动制动蹄片向外运动，使摩擦衬垫作用于连接车轮的制动鼓。使车轮停止。无论哪一种情况，盘式制动系中的摩擦表面，还是鼓式制动器中的制动鼓都是把车轮的往复运动转变为热能。热能就是使制动衬垫和制动蹄上的摩擦消失并且代替。鼓式制动器如果盘式制动器市场很大，为何我们仍然使用鼓式制动器？原因在于成本。而所有车辆零件的生产，多年来采用前盘式，后轮生产鼓式是由于它的价格