汽车底盘中英文翻译
1 .Chassis
The chassis is an assembly of those systems that are the major operating part of a vehicle. The chassis includes the transmission, suspension, steering, and brake systems.
Transmission systems ― conveys the drive to the wheels. The ma in components are clutch, gearbox, driveshaft, final drive, and differential.
Suspension― absorbs the road shocks.
Steering― controls the direction of the movement.
Brake― slows down the vehicle.
Automobile Brake System
The braking system is the most important system in cars. If the brakes fail, the result can be disastrous. Brakes are actually energy conversion devices, which convert the kinetic energy (momentum) of the vehi
cle into thermal energy (heat).When stepping on the brakes, the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes.
Two complete independent braking systems are used on the car. They are the service brake and the parking brake.
The service brake acts to slow, stop, or hold the vehicle during normal driving. They are foot-operated by the driver depressing and releasing the brake pedal. The primary purpose of the parking brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by when a separate parking brake foot pedal or hand lever is set.
The brake system is composed of the following basic components: the “master cylinder”which is located under the hood, and is directly connected to the brake pedal, converts driver foot’s mechanical pressure into hydraulic pressure. Steel “brake lines”and flexible “brake hoses”connect the master cylinder to the “slave cylinders”located at each wheel. Brake fluid, specially designed to work in extreme conditions, fills the system. “Shoes”and “pads”are pushed by the slave cylinders to contact the “drums”and “rotors”thus causing drag, which (hopefully) slows the car.
The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder.
Basically, all car brakes are friction brakes. When the driver applies the brake, the control device forces brake shoes, or pads, against the rotating brake drum or disks at wheel. Friction between the shoes or pads and the drums or disks then slows or stops the wheel so that the car is braked.
In most modern brake systems, there is a fluid-filled cylinder, called master cylinder, which contains two separate sections, there is a piston in each section and both pistons are connected to a brake pedal in the driver’s compartment. When the
brake is pushed down, brake fluid is sent from the master cylinder to the wheels. At the wheels, the fluid pushes shoes, or pads, against revolving drums or disks. The friction between the stationary shoes, or pads, and the revolving drums or disks slows and stops them. This slows or stops the revolving wheels, which, in turn, slow or stop the car.
The brake fluid reservoir is on top of the master cylinder. Most cars today have a transparent reservoir so that you can see the level without opening the cover. The brake fluid level will drop slightly as the brake pads wear. This is a normal condition and no cause for concern. If the level drops noticeably ove
r a short period of time or goes down to about two thirds full, have your brakes checked as soon as possible. Keep the reservoir covered except for the amount of time you need to fill it and never leave a cam of brake fluid uncovered. Brake fluid must maintain a very high boiling point. Exposure to air will cause the fluid to absorb moisture which will lower that boiling point.
The brake fluid travels from the master cylinder to the wheels through a series of steel tubes and reinforced rubber hoses. Rubber hoses are only used in places that require flexibility, such as at the front wheels, which move up and down as well as steer. The rest of the system uses non-corrosive seamless steel tubing with special fittings at all attachment points. If a steel line requires a repair, the best procedure is to replace the compete line. If this is not practical, a line can be repaired using special splice fittings that are made for brake system repair. Y ou must never use copper tubing to repair a brake system. They are dangerous and illegal.
Drum brakes, it consists of the brake drum, an expander, pull back springs, a stationary back plate, two shoes with friction linings, and anchor pins. The stationary back plate is secured to the flange of the axle housing or to the steering knuckle. The brake drum is mounted on the wheel hub. There is a clearance between the inner surface of the drum and the shoe lining. To apply brakes, the driver pushes pedal, the expander expands the shoes and presses them to the drum. Friction between the br
ake drum and the friction linings brakes the wheels and the vehicle stops. To release brakes, the driver release the pedal, the pull back spring retracts the shoes thus permitting free rotation of the wheels.
Disk brakes, it has a metal disk instead of a drum. A flat shoe, or disk-brake pad, is located on each side of the disk. The shoes squeeze the rotating disk to stop the car. Fluid from the master cylinder forces the pistons to move in, toward the disk. This action pushes the friction pads tightly against the disk. The friction between the shoes and disk slows and stops it. This provides the braking action. Pistons are made of either plastic or metal. There are three general types of disk brakes. They are the floating-caliper type, the fixed-caliper type, and the sliding-caliper type. Floating-caliper and sliding-caliper disk brakes use a single piston. Fixed-caliper disk brakes have either two or four pistons.
transparent中文翻译Steering System
Basic Parts of Steering System
The steering converts the steering –wheel rotary motion into a turn motion of the steered wheels of the vehicle .
The basic steering system in most cars is the same . The steering gear of steering box is the heart of t
he steering system .This is usually next to the engine . A shaft extends from the back of the steering gear . This shaft is connected to the steering column or steering shaft . The steering wheel is at the top of the steering column . Another shaft comes from the bottom of the steering gear . This shaft connects to the arms , rods , and links . This parts assembly , called the steering linkage , connects the steering gear to the parts at the wheels . The wheels and tires mount to the steering knuckles , the knuckles are pivoted at the top and bottom . Thus , the wheels and rites can turn from side to side .
While the steering system may look complicated , it works quite simply . When a driver drives a car straight down the road , the steering gear is centered . The gear holds the linkage centered so that the wheels and tires point straight ahead . When the driver turns the steering wheel , the steering shaft rotates and the steering gear moves toward that side . The shaft coming out the bottom of the steering gear turns , as well . When the shaft turns , it pulls the linkage to one side and makes the steering knuckles turn slightly about their pivot points . Thus , the steering knuckle , spindle , wheels , and tires turn to one side , causing the car to turn .
The type of steering layout depends on the suspension system . The beam axle used on heavy commercial vehicle has a king pin fitted at each end of the axle and this pin is the pivot which allows the wheels to be steered . Cars have independent suspension and this system has ball joints to allow f
or wheel movement .
Types of Steering System
A steering box must have the following qualities :
1) no play in the straight-ahead position
2)low friction , resulting in high efficiency
3)high rigidity ,
4)readjustability
For these reasons , these are several different types of steering gears . However , there are only two types of steering systems : manual steering systems and power steering systems . In the manual type , the driver dose all the work of turning the steering wheel , steering gear , wheels and tires . In the power , hydraulic fluid assists the operation so that driver effort is reduced .
On today’s cars , two types of steering systems commonly are used to provide steering control :
1) recirculating ball
2) rack and pinion
Either of these two types of steering mechanisms may be a fully mechanical systems or a power –assisted system .
Front Suspension
The front suspension is more complicated than the rear suspension . This is because the front wheels must move in several different directions . The wheels must move up and down with the suspension and turn left to right with the steering . Since the car goes in the direction in which the front wheels point , the alignment of the front wheels is important . The wheels must point in just the right direction for the car
to move straight down the road and turn properly .
Modern cars uses an independent front suspension . In this system , each wheel mounts separately to the frame and has its own individual spring and shock absorber . Thus , the wheels act independently of one another . When one wheel hits a bump or hole in the road , the other wheel dose not deflect .
Front Wheel Alignment
As a car moves down the high-way , the suspension moves the front wheels up and down . At the same time , the steering mechanism moves the front wheels , sometimes to make turns and sometimes to make the travel straight . The angular relationship between the wheels and suspension parts during this motion is the front-end geometry . Since the geometry can change the alignment of front wheels is adjustable . Y ou can change the adjustment to compensate for spring sag .
The alignment of the front wheels affects the operation of a car . Poor alignment can make a car pull to one side and stop the front wheels from returning to the straight-ahead position after a turn . The three normally adjustable angles are caster , camber , and toe .
Rear Suspension
The purpose of the rear suspension is to support the weight of the rear of the vehicle . As with the front suspension , this system contributes to the stability and ride of the vehicle . Rear suspension may be of the solid axle or independent design . Many cars have solid axle rear suspension . Either design may have different kinds of springs , including torsion bars . However , the coil spring and leaf spring types are most popular .
Wheels
The rim is made in one piece , with the wheel center welded or riveted to it . Most modern vehicles use the drop center type . This drop center provides a well for tire bead to drop into for tire removal . A slight hump at the head ledge holds the tire in place should it go flat while driving .
Tires
Tires are important to your safety and comfort . They transmit the driving and brak ing power to the road . The car’s directional control , road-ability and riding comfort are greatly dependent on the tires . Tires should be selected and maintained with great care .
There are two basic types of tires –those with inner tubes and those without ( called “tubeless” tires ) . Most modern automobile tires are of the tubeless type . Truck and bus tire are usually of the tube type .
Tires are made of several layers of nylon , rayon , or polyester fabric bonded together with belts of rayon , fiberglass , or steel cord . The rubber used in tires is a blend of natural and synthetic rubber .
2.底盘
底盘由汽车的主要操作部分组合而成。它包括传动系统、悬架、转向系统、制动系统。
传动系统——驱动车轮。主要部件为离合器，变速箱，驱动轴，驱动桥和差速器。
悬架——吸收路面冲击。
转向系统——控制行驶方向。
制动系统——停车。
制动系统
制动系统是汽车中最重要的系统。如果制动失灵，结果可能是灾难性的。制动器实际上是能量转化装置，它将汽车的动能（动量）转化成热能（热量）。当驾驶员踩下制动踏板，所产生的制动力是汽车运动时动力的10倍。制动系统能对4个刹车系统中的每一个施加数千磅计的力。
每辆汽车上使用两个完全独立的制动系统，即行车制动器和驻车制动器。
行车制动器起到减速、停车、或保持车辆正常行驶的作用。行车制动器是由司机用脚踩、松制动器踏板来控制的。驻车制动器的主要作用是当车内无人时保持汽车静止不动。当独立的驻车制动器踏板或手杆被安装时，驻车制动器就被机械地操作。
制动系统由下列的基本部件组成：位于发动机罩下方直接被连接到制动踏板的“制动主缸”，它把驾驶员脚的机械力转化为液压力。钢制的“制动管路”和有柔性的“制动软管”将制动主缸连接到每个轮子的“制动轮缸”上。制动液, 特别是为工作在极端情况而设计的，填充在系统中。“制动蹄”和“衬块”是被制动轮缸推动接触“圆盘”和“回转体”如此引起缓慢的拖拉运动, (希望)使汽车减慢速度。
典型的制动系统由前后盘式或者前盘后鼓式组成，各个车轮上的制动器通过一系列的管路系统连接到制动主缸。
基本上，所有的汽车制动器都是摩擦制动器。当司机刹车时，控制装置会迫使制动蹄或制动衬片与旋转的制动鼓或制动盘接触。接触后产生的摩擦使车轮转动变缓或停止，这即是汽车的制动。
在最新制动系统中，有一个内部冲门制动液的制动主缸。它包含两个独立部分，每个部分里都有一个活塞，并且两个活塞都连接到驾驶室的制动踏板。当制动踏板被踩下时，制动液将从制动主缸流入轮缸。在轮缸中，制动液推动制动蹄或制动衬片与旋转的制动鼓或制动盘接触。接触后产生的摩擦力使汽车的运动逐渐减缓或停止。
制动液的储液室位于制动主缸的顶部。目前大多数汽车都有个容易看见的装制动液的储液室，为的是不用打开盖子就可以看到制动液的油面。正常无外因情况下，随着制动踏板的运动制动液油面缓慢地下降。如果制动液在很短的时间内下降明显或者下降了三分之二，就须立即检查你的制动系统。保持储液
室充满制动液除非你需要维修它，制动液必须保持很高的沸点。暴露在空气中的制动液会吸收湿气引起制动液低于沸点。
制动液通过一系列的管路从主缸到达各车轮。橡胶软管只用在要求柔性的地方，例如在前轮，在车的行进中上下来回运动。系统的其它部分在所有的连接点上都专门使用了无腐蚀无缝钢管。如果钢线需要修理的话，最好的方法就是取代