(重庆交通大学汽车工程专业英语第四章.docxVIP

第四章Braking System（制动系统）1.Energy is required when a vehicle is accelerated from rest to a certain speed. A proportion of that energy is now stored in the vehicle and is called kinetic energy. In order to reduce the speed of the vehicle, the brakes have to convert the kinetic energy to heat energy; the speed of conversion governs the rate at which the vehicle slows down.汽车从原地起步加速到某一速度需要能量。储存在汽车中的那部分能量称为动能。要降低车速,制动器必须把汽车的动能转换为热能；转换的速度决定了汽车减速的快慢。2.The three types of braking systems are in use today: service braking system, parking braking system and additional retarding-braking system. The service braking system and the parking braking system have separate control and transmission devices. The service braking system is normally foot-operated, while the parking braking system is hand-operated.目前使用的制动系统有三种类型：行车制动系，住车制动系和辅助制动系．行车制动系和住车制动系有独立的控制和传动装置．行车制动系通常使用脚刹，而驻车制动系通常使用手刹．3.Two types of brakes are used in modern cars: drum brakes and disc brakes. Since 1976, all cars have used disc brakes on the front wheels. Most cars use drum brakes on the rear wheels . In both drum and disc brakes, a hydraulic system applies the brakes. The hydraulic system connects the brake pedal to the brake parts at each wheel.目前使用的制动器有两种类型：鼓式制动器和盘式制动器．从1976年开始，所有的汽车前轮都使用盘式制动器, 大部分汽车后轮使用的是鼓式制动器. 在盘式制动器和鼓式制动器中都使用液压系统. 液压系统把制动踏板与每个车轮的制动部件相连接.4.These have two shoes, anchored to a stationary back-plate, which are internally expanded to contact the drum by hydraulic cylinders or a mechanical linkage.这种制动器有两个固定在制动底板上的制动蹄，通过液压轮缸或机械杆系作用从内侧向外推开与制动鼓接触。5.In the case of the simplex brake, C*(brake factor) is the sum of the values for the individual shoes, and is ≈2.0（referred to a specific coefficient of friction)．A disadvantage of this design is the great difference in the braking effect between the two brake shoes, and the resulting greatly increased wear on the leading shoe. For this reason, the trailing shoe is often equipped with a much thinner lining than the leading shoe.就领从蹄而言， C*表示各蹄的值的总数，且≈２.０ (特指某一