汽车专业外文翻译(英文+译文).doc

毕业设计论文外 文 翻 译原文：Routine brake system maintenanceThe braking system is the most important system on a car. If the brakes dont work properly, the result can be disastrous. So the good brakes are essential for safety.There are two completely independent braking systems on a car. One is the service brake, and the other is 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 parking brakes purposes are to hold a car stationary while it is unattended, and to keep the car from rolling on unleveled ground. It is also called the handbrake. Basically, all car brakes are friction brakes. When the driver applies the brake, the control device will force brake shoes or pads against the rotating brake drums or discs at wheels. Friction between the shoes or pads and the drums or disks then slows or stops the wheels so that the car is braked.Disc brakeDisc brakes are used on the front wheels of most cars and on all four wheels on many cars.The main components of a disc brake are the brake pads, the caliper which contains a piston, and the rotor which is mounted to the hub.The disc brake is a lot like the brakes on a bicycle. Bicycle brakes have a caliper, which squeezes the brake pads against the wheel. In a disc brake, the brake pads squeeze the rotor instead of the wheel, and the force is transmitted hydraulically instead of through a cable. Friction between the pads and the disc slows the disc down.A moving car has a certain amount of kinetic energy, and the brakes have to remove this energy from the car in order to stop it. The brakes convert the kinetic energy to heat generated by the friction between the pads and the disc, so the car stops.Drum brakeSo if disk brakes are so great, how come we still have cars with drum brakes? The reason is cost. While all most vehicles for many years have disk brakes on the front wheels, drum brakes are cheaper to produce for the rear wheels. Drum brake is shown in Fig.Drum brakes consist of a backing plate, brake shoes, brake drum, wheel cylinder, return springs and an automatic or self-adjusting system. When you apply the brakes, the wheel cylinder pushes the brake shoes into contact with the machined surface on the inside of the drum. When the pressure is released, return springs pull the shoes back to their rest position. As the brake linings wear, the shoes must travel a greater distance to reach the drum. When the distance reaches a certain point, a self-adjusting mechanism automatically reacts by adjusting the rest position of the shoes so that they are closer to the drum.Hydraulic Brake SystemsWhen the operator steps on the brake pedal, the brake pedal operates a hydraulic system.The typical brake system is composed of the following basic components(1) Master cylinder. That is directly connected to the brake pedal, converts your foots mechanical pressure into hydraulic pressure.(2) Brake lines and brake hoses, they connect the master cylinder to the wheel cylinders located at each wheel.(3) Brake fluid: that is special oil that has special properties. It is designed to withstand cold temperature without thickening as well as very high temperature without boiling. In the brake system, master cylinder contains two separate sections, there is a piston in each section and both pistons are connected to a brake pedal in the drivers 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, which can slow and stop car. This slows or stops the revolving wheels, which, in turn, slow or stop the car.Routine maintenance of automobile brake fluid: Usually brake fluid maintenance period of 2 years or 48,000 km. Recommended brake fluid on the maintenance period, the European car manufacturers generally set a few years; and Japan and the United States car manufacturers are generally in their owners manual have detailed descriptions. The abs function with anti-lock braking system, brake fluid and timely supplement is especially important. This is mainly due to energy storage in the pollution of dust and moisture of the body will lead to expensive failure, and thus laid security risk when vehicle braking force owners to find weak, you can use brake fluid test strips humidity assisted analysis of whether there is any fault of defect caused by brake fluid. If the brake fluid for the failure of the root causes of lack of sufficient quantity to be added in time brake fluid. By the brake fluid tank vent in a normal infiltration (or when tank lid open non-regular access to) the moisture and dust reduced brake fluid maintenance cycle. Maintenance of the brake fluid in the same time, must not neglect the wheel brake parts. Auto brake pad, brake drum, rotating body, and brake calipers: the current drive vehicle for leading the trend, people are concerned about how to play the 2 / 3 of the front brake lines brake tasks for scientific and effective maintenance. Now, after a variety of drive, all-wheel drive, trucks and suv blossom everywhere, people before re-light after the traditional concept has gradually changed.Gradually replace the asbestos linings in the semi-metallic brake pad will cause the whole surface of rotating serious wear and tear. Brake parts on the car wheel or brake pad inspection is a complex task, not simply from a visual look at both sides of the front brake pads wear the middle point. In actual operation, even if the brake caliper of open distance just to let you see both sides of the brake pad, it does not mean we can be handy, unimpeded operation of the. In addition, the popularization of brake shield, and the brake pad of rotating the contact surface is multi-block, hard look. As for the rear wheel with disc brake, it is hidden, is difficult to comprehend the appearance.Typically, the only system in the apparent leak, we will focus on checking brake fluid sealing. The comprehensive system of inspection, including the traditional static checking (that is, to find leaks in situ static) and dynamic checks (ie check the seal during braking). In any case, when the vehicle braking system to maintain up to 48 000 km driving range, they need the vehicles braking system to conduct a comprehensive professional maintenanceBrake rotating body of minor scratches do not cause illness. But since the fastening nut tightening force thickness of inequality and uneven brake rotating body rotation caused by excessive wear and tear will seriously affect the braking performance. To reduce weight, many rotating body size using unconventional structure, which is difficult to meet some of the machine tool clamping the basic requirements. If you find a rotating body has been processed, then follow the same axle of the second rotating body is only the size of its replacement. In theory, you can only replace a rotating body, but to get the best balance between braking effect, or the proposed replacement with two on the same axle rotating body. The proposal also applies to vehicles during braking, brake caliper piston through the experience back movement, we can complete the key features of the automatic brake calipers inspection. If the brake caliper piston back position is unsound, please replace a new brake caliper; If you want to discharge or filling brake fluid, make sure relief valve can be normally open; if the relief valve setting, replace the new The brake caliper.If the asbestos linings have worn 3.175mm, this time even under light loading, the security of driving range has also been very limited. Also, if needed at this time of high load brake, the wear lining weak braking force will make the traffic safety compromised.Some rear disc brake, rear-drive rotary body with a cap, the cap body also acts as a rotary brake drum. There are many car owners often overlook the parking brake will cancel the direct-drive vehicles, the rotating body and the brake shoes in direct metal - metal friction, the result is bound to cause a rotating body, brake pads and brake shoes of serious wear and tear.译文：汽车制动系统的日常维修保养制动系统是汽车上最重要的系统。如果制动系统不能正常工作，后果不堪设想。因此良好的制动系统是安全所必需的。车上有两种完全独立的制动系统，一种是行车制动，一种是驻车制动。行车制动能够在汽车正常行驶过程中使汽车减速或停车，这个过程是通过驾驶员踩下或松开制动踏板实现的。驻车制动也叫手刹，它的作用是在车辆停止时，保持车辆不动，防止车轮滚动。基本上所有的制动都是摩擦制动。当踩下刹车时，控制机构推动制动蹄片或制动块，阻止制动鼓或制动盘转动。制动蹄片或制动块与制动鼓或制动盘之间产生摩擦，降低或停止车轮的转动速度，以使汽车制动。盘式制动器 大多数汽车的前轮和所有四轮驱动汽车的四个轮子采用盘式制动器。 盘式制动器的主要组成部分有摩擦+t-g，内部有活塞、卡钳和固定在轮毂上的转子。 盘式制动器有点像自行车的制动系统。自行车的制动系统有个卡钳，与制动衬块压紧，制动衬块与车轮固定在一起，而汽车的盘式制动器中，制动衬块与转子压g-，而不是与车轮，并采用制动液传递动力，而不是钢丝绳。摩擦衬块与制动盘之间的摩擦力使制动盘的转速降低。行驶中的汽车有一定动能，制动器必须将此能量从汽车上移除，汽车才能停下来。只有通过摩擦衬块和制动盘之间的摩擦，制动器才能将动能转化成热能，汽车才能停下。鼓式制动器 既然盘式制动器好，为什么仍有很多车采用鼓式制动器呢?原因是价格便宜。多年来，大多数汽车前轮采用盘式制动器，后轮采用鼓式制动器。鼓式制动器。 鼓式制动器包括底板、制动蹄、制动鼓、轮缸、回位弹簧和机械的或自动的调节装置。当制动器工作时，轮缸推动制动蹄，使其与制动鼓的内侧面接触。当制动压力解除，在回位弹簧的作用下，制动蹄回到原来的位置。当摩擦片磨损，制动蹄与制动鼓之间的间隙变大。如果这个间隙增大到一定程度，自动调节装置就会调节制动蹄的位置，使制动蹄与制动鼓之间的间隙减小。液压制动系统当驾驶员踩下制动踏板，制动踏板控制整个液压系统。典型的制动系统包括以下几个基本组成部分。(1)主缸：直接与制动踏板连接，将脚的机械压力转换成液压。(2)制动管路和制动软管：它们将主缸与各车轮的轮缸连接起来。(3)制动液：这是一种具有特殊性能的油。这种油能够在低温下不凝固，高温下不沸腾。在制动系统中，主缸分成独立的两部分，每部分里面都有一个活塞，两个活塞都与驾驶室的制动踏板相连，当制动踏板被踩下时，制动液从主缸被送到车轮的轮缸中，车轮的轮缸中，液体推动制动蹄片或制动块阻止制动鼓或制动盘的转动，这样可降低车速或制动汽车。汽车制动液的日常保养：通常制动液的维护周期为2年或者4.8万km。关于制动液的推荐维护周期，欧洲汽车制造商笼统地定为几年；而日本和美国的汽车制造商则在其车主手册中一般都有详细的描述。对于具有防抱死abs功能的制动系统，及时地补充制动液就显得尤为重要。这主要是由于其蓄能器中灰尘和湿气的污染会导致价格不菲的阀体发生故障，并由此埋下安全隐患当车主发现汽车制动力衰弱时，可以使用制动液湿度测试纸辅助分析故障原因是否因制动液缺损所致。如果