外文翻译--汽车车架的单体结构

附 录 附录 A The frame is the most basic test bench car, all the suspension and turned to connect components are installed in frame above. If car frame flexible is too big, can make cars can neither turned, also cannot normal control. And if the car too rigid frame structure, and would cause unnecessary vibration passed to the driver and passengers seat cabins. Auto frame and suspension structure design is not only the vehicle noise size and the decision of the vibration amplitude strength, but also will affect the quality of the car and the normal control vehicle. Car manufacturers in their production car are used in several different frame structure. Among them, through the seventy s the most commonly used is shell and girders of fission structure. At present it is still in large trucks, small tonnage truck and a truck on the application. In car shell and the beam structure in the fission, engine, transmission device, transmission gear and the car is through shell insulation devices in the body on the sole fixed. The frame of the internal insulation devices is artificial rubber pad to be able to stop road uneven and engine noise and vibration of the work related to the driver and passengers cockpit. The second is the single structure of automobile frame. This kind of design so far in the modern car is the most commonly used. According to the strength of the frame monomer to points, design have light structure. In this car structure as part of the beam frame welding to be directly on the shell. The weight of the chassis increased the strength of the beam. Transmission gears and transmission device via big and soft artificial rubber insulation mat installed in the frame monomer. Insulation pad weakened the noise transmission and vibration. If the insulation pad too soft, will cause transmission gears and transmission device displacement. The displacement called soft quantity, it will affect the manipulation of car performance and control performance. If the insulation pad too hard, cannot play its isolation and reduce the role of the vibration noise. Car manufacturers well-designed insulation mat, put them in proper place device car, in order to reduce the noise, vibration, make the transmission buffer for driving car, drivers and passengers take comfort. The performance of the insulation mat with use fixed number of year changing, when the old car becomes the performance of the original also changed. He third kind of structure is the first two kinds of structure of the main characteristics unifies in together. It in front of the car used car beam, in the short HouCang use a frame. A monomer, and short rigid part of the beams action is insulation to enhance the car. Car manufacturers in the car that choose low production cost and at the same time to meet with noise, vibration control performance requirements of high driving frame structure. The old large vehicles, trucks, and trucks often use shell and girders of fission structure. A new, smaller vehicles often use single structure frame. Engine piston connecting rod group The piston connecting rod group of piston, piston, piston pins, connecting rod, connecting rod bearings etc. Function: the piston is the work of gas pressure to bear, and through the piston pin to connecting rod rotation, the piston driven crankshaft top or part of the combustion chamber. Working conditions: the piston in high temperature and high pressure, high speed, bad lubrication under the conditions of the job. The piston directly with high temperature, gas contact instantaneous temperatures up to 2500 K above, therefore, heat, and cooling conditions and serious is very poor, so the piston work temperature is very high, the top as high as 600 to 700 K, and the temperature distribution is not uniform； The piston top bear gas pressure to do work, especially the greatest pressure, the gasoline engine trip up to 3 5 MPa, diesel engine as high as 6 9 MPa, this makes the piston impact, and bear the role of the lateral pressure, therefore, the piston should have enough heat resistance, to try to reduce the piston, piston cooling heating strengthen heat transfer surface, suitable enlargement, make the tops of the pistons. The highest temperature drop Inside the cylinder piston at high speed (8 to 12 m/s) reciprocating motion, and speed changing constantly, which has made a big inertia force, driving the piston is much additional load. The piston in this harsh conditions, can produce deformation work and accelerated wear, still can produce additional load and thermal stress, and the chemical corrosion function by gas. In order to reduce reciprocating inertia force, must reduce the weight of the piston as much as possible. The piston is in high temperature and high pressure, high speed (piston average speed can reach 101115 m/s) under the working conditions of the poor, the lubrication, piston and cylinder wall friction between serious. To reduce the friction, the piston surface must wear-resisting. Requirements: 1)To have enough stiffness and strength, power transmission and reliable； 2)Thermal conductivity, resistance to high pressure, high temperature resistant, wear resistance； 3) Quality, light weight, small to minimize reciprocating inertia force. Aluminum alloy material basically meet the above requirements, therefore, the piston typically use the high-strength aluminum alloy, but in some low speed diesel engine USES the senior cast iron or heat resistant steel. Suspension system Suspension shock absorbers and control including a spring, connecting rod device. It must be able to support the body weight and enough to load. Suspension also should be able to withstand the engine and braking to it an opposite reaction. Suspension system is the most important function of the tire and road surface contact time as far as possible the long. In support of body and load, even in rough roads should be more so. The four tire tread come in contact with the car is the only part. All output power, engine to force and power system through come in contact with the pavement of the tire tread work. Whenever tires and road surface contact or car started when the car skid, control ability (power, to force, braking force) will be weakened or even lost. Car body is supported by spring, spring can be divided into the spiral, steel plate type, twist bar type and inflatable. The spiral spring is the most widely used in modern car type. The spiral, torsion bar type and inflatable spring is need to use the connecting rod and connecting with the wheel arm in place. Leaf spring provide the horizontal and vertical vehicle control, in order to prevent the car wheel in cars, they often unnecessary displacement with truck in the van and truck. Suspension system is along with the development of the passenger car and change and improvement. A luxury car, special vehicle, small cars and light trucks are designed completely different. Modern tire improvement continuously improve the vehicles operating performance, it is the improvement and shock absorbers, steering system and suspension control device of synchronous improvement together. In modern car of the manipulation conditions need to tires and the road, so that safe, correct contact to control and motor vehicles. To want to maximum driving safety, to remember this four tires must in any time and the road phase contact. At the same time to consider the vehicle steering flexibility, tire wear resistance, automobile driving comfort and driving safety, in order to achieve the effective control of the car. Suspension system is divided into front suspension and after suspension. The front suspension design has been rapid development. From relatively coarse hard shaft structure to the development of the modern light, high strength, support type independent suspension structure, and by increasing the connecting rod device and make the cars performance is improved. Suspension structure is improved with the improvement of the road, and drivers need and the improvements. Most lead the engine, rear wheel drive car USES a simple after the dependency of the suspension. But a rear wheel drive independent suspension structure is complex, and high cost, and only used for a bus. To lead the engine of the car front wheel drive, through the transmission device, moved to the front suspension after only used to regulate driving control and the reaction of braking. This has the simplified of independent suspension institutions, half independent suspension institutions and independent suspension after the application, the latter a large institutions used in the design of the structure of new vehicles. 附录 B 车架是汽车最基本的台架，所有的悬架和转向连接部件都安装在车架上面。如果汽车车架柔性过大，会使汽车既无法转向，也无法进行正常操纵。而如果汽车车架结构刚性过大，又会引起不必要的震动传递给驾驶员和乘客的座舱室。汽车车架和悬架的结构设计不仅决定了汽车噪声大小和震动的幅度强度，而且也将影响到汽车的质量和车辆的正常操纵。 汽车制造厂商们在他们生产的汽车上都使用了几种不同的车架结构。其中，整个七十年代最常使用的是壳体和大梁的分体结构。目前它仍然在大型货车、小吨位货车和卡车上应用着。在汽车壳体和大梁的分体结 构里，发动机、传动装置、传动齿轮和车壳都是通过绝缘装置固定在车身大梁上。车架内部的绝缘装置是人造橡胶缓冲垫，能够阻止道路不平和发动机工作引起的噪音和震动传到驾驶员和乘客的座舱里。 第二种是汽车车架的单体结构。这种设计到目前为止在现代汽车上是最常用。单体车架按所需的强度来分，设计有轻型结构。在这种汽车结构中大梁作为车架的一部分被直接焊接到壳体上。底盘的重量增加了大梁的强度。传动齿轮和传动装置经由大而软的人造橡胶绝缘垫安装在单体车架上。绝缘垫减弱了噪声的传动和震动。若绝缘垫太软，将会引起传动齿轮和传动装置位移。 这种位移称为柔量，它会影响到汽车的操纵性能和控制性能。若绝缘垫太硬，则不能起到应有的隔绝噪音和减小震动的作用。汽车制造厂商们精心地设计绝缘垫，把它们装置在汽车适当的地方，以降低噪声，缓冲震动的传送，使汽车便于驾驶，驾驶员和乘客乘坐舒适。绝缘垫的性能随使用年限发生变化，当汽车变旧时原先的性能也随之改变。 第三种结构是把前两种结构的主要特点结合在一起。它在汽车前舱使用了短车梁，在汽车后舱使用了单体车架。单体部分刚性很大，而短的车梁增强了绝缘作用。 汽车制造厂家们在汽车上选择那种生产成本低而同时又符合对噪音震动， 驾驶操纵性能要求很高的车架结构。老式的大型的车辆、货车、和卡车通常使用壳体和大梁的分体结构。较新的，较小型的车辆通常使用单体结构的车架。 发动机活塞连杆组 活塞连杆组由活塞、活塞环、活塞销、连杆、连杆轴瓦等组成。 功用：活塞的功用是承受气体压力，并通过活塞销传给连杆驱使曲轴旋转，活塞顶部还是燃烧室的组成部分。 工作条件：活塞在高温、高压、高速、润滑不良的条件下工作。活塞直接与高温气体接触，瞬时温度可达 2500K 以上，因此，受热严重，而散热条件又很差，所以活塞工作时温度很高，顶部高达 600 700K，且温度分 布很不均匀；活塞顶部承受气体压力很大，特别是作功行程压力最大，汽油机高达 3 5MPa，柴油机高达 6 9MPa，这就使得活塞产生冲击，并承受侧压力的作用，因此，活塞应有足够的耐热性，要尽量减小活塞的受热面，加强活塞的冷却，适当增大传热面，使活塞顶部的最高温度下降。活塞在气缸内以很高的速度 (8 12m/s)往复运动，且速度在不断地变化，这就产生了很大的惯性力，使活塞受到很大的附加载荷。活塞在这种恶劣的条件下工作，会产生变形并加速磨损，还会产生附加载荷和热应力，同时受到燃气的化学腐蚀作用。