汽车专业英语(幻灯片)chapter 4 body.ppt
Body,Question 1:List the types of BODY.,separate frame construction,unitized body construction,semi-integral body construction,A separate frame must be light yet strong enough to resist the various loads and road forces.Commercial vehicles normally use a separate steel frame to provide the rigidity needed to support the various loads.The two long side members of channel section are riveted to a number of cross members to give a low weight frame which offers great resistance to bending,twisting.,分离式车架必须足够轻巧而且结实，以承受变化的载荷和路面作用力。商用车通常使用分离式钢质车架，以获得较好的刚度来承受变化的载荷。两根槽形的长纵梁铆接着很多横梁，这使车架重量较轻，具有较好的抗弯和抗扭能力。,Most cars use a unitized body construction,a combined body and frame.Unitized body construction is lighter than body/frame construction,but noisier.Rubber mounts are used between the body section and mechanical parts to absorb vibrations.The floor pan is made of sections that support the rear suspension and the transmission.,多数轿车采用承载式车身，也就是车身和车架融为一体。承载式车身比非承载式车身质量轻，但噪声大。在车身和机械部件之间安装橡胶块以吸收振动。地板由一些支撑后悬架和变速器的部件组成。,Modern cars have a blend-air system that mixes warm and unwarmed air to heat the car.The heart of the system is the heater core.Hot engine coolant flows from the radiator,through the water pump hoses,and to the heater core.Therefore,the heater core is always hot.The temperature of air entering the passenger compartment is controlled by the amount of air moving through the heater core.This heated air is blended with fresh,cool air that bypasses the heater.Small doors in the heating system regulate the air-flow.Control levers on the dash panel open and close these doors to direct air to the heat ducts and window defrosters.,多数汽车采用加热过的或未加热过的空气的混合起来加热汽车。暖风系统的核心是热芯。热的冷却水来自散热器，通过水泵软管流到热芯。这样，热芯总是热的。流经热芯的空气数量控制着进入车厢的空气温度。加热后的空气同流经加热器的新鲜冷空气混合。加热系统中的一些小风门控制空气的流量。前围板上的控制杆开启和关闭这些风门，从而将空气引入输热管和风窗除霜器。,The purpose of venting systems is to draw in fresh air and remove stale air from the interior of the car.Fresh air venting systems direct air to two different places.First,they can direct outside air into the heater housing.This air either can bypass the coil or it can be heated by the coil.Second,the air can move directly into the passenger compartment through small vent doors in the dash panel or at floor level.Venting also can take place by opening the windows.,通风系统吸入新鲜的空气，排除车内不新鲜的空气。通风系统将新鲜空气引入两个地方。首先，通风系统将外部空气引入加热器壳里，空气从线圈旁流过或被线圈加热。其次，空气可通过前围板或地板上的小风门直接将空气引入车厢.打开车窗也可实现通风。,Levers and switch to regulate air and heat are located on the dash panel.Some heater controls use small vacuum motors for simpler,more positive action.Others use cables,while some use a combination of the two.The vacuum to operate the motors comes from the engine intake manifold.控制空气和热量的杠杆和按钮安装在仪表板上一些加热器的控制器使用真空电动机提供简单可靠的工作另一些使用缆线，还有一些两者兼用驱动电动机的真空来自发动机的进气管,Question 2:List the parts of A/C system.,As the compressor raises the pressure of the refrigerant,it also heats it.The hot refrigerant is then pumped into the condenser,where it cools by giving off heat to air passing over the condenser fins.As the refrigerant cools,it condenses into a liquid.Still under high pressure,the refrigerant passes into the receiver.The receiver acts as a storage tank to furnish refrigerant to the expansion valve at all times.From the receiver,the high-pressure liquid refrigerant passes to the expansion valve.,压缩机增加制冷剂的压力，对制冷剂进行加热。高温的制冷剂被吸入冷凝器中，将热量释放给流经冷凝器散热片的空气而得到冷却。制冷剂冷却时冷凝为液体。在高压作用下，制冷剂进入储液器。储液器不断地给膨胀阀供应制冷剂。高压液态的制冷剂从储液器流向膨胀阀。,The expansion valve controls the flow of refrigerant into the evaporator,where a low pressure is maintained by the suction side of the compressor.As it enters the evaporator,the refrigerant begins to boil by absorbing the heat from the air passing over the evaporator core.Having given up its heat to boil the refrigerant,the air is cooled and passes into the passenger compartment.The refrigerant continues to boil in the evaporator until all the liquid has vaporized.From the evaporator,the refrigerant flows back to the compressor to repeat the cycle.,膨胀阀控制着进入蒸发器的制冷剂流量，在蒸发器里压缩机吸入端保持低压。制冷剂进入蒸发器时，吸收流经蒸发器芯的空气的热量而沸腾。空气释放热量使制冷剂沸腾，得到冷却后进入车厢。制冷剂在蒸发器里持续沸腾直到液体完全蒸发为止。制冷剂从蒸发器流回压缩机，重复吸热制冷循环。,
