汽车与变速箱
随着世界能源危机的持续，以及战争和能源-----石油的消耗及汽车饱有量的增加，能源在一天一天下降，终有一天它会消失的无影无踪。石油不是在生资源。所以必须在石油耗净之前到一种代替品。随着科技的发展社会的进步，有人发明了电动汽车。电动汽车将成为人们最为理想的交通工具。
世界在发展各各方面都取得丰硕成果，尤其是随着汽车电子技术和计算机以及发展迅速的信息时代。电子控制技术在汽车上得到了广泛应用，汽车上应用的电子装置越来越丰富，电子技术不仅用来改善和提高传统汽车电器的质量和性能，而且还提高了汽车的动力性、燃油经济性、可靠性以及废气排放的净化性。汽车上广泛使用电子产品不仅降低了成本，并且减少维护的复杂性。从发动机的燃油喷射点火装置、进气控制、废气排放控制、故障自诊断到车身辅助装置都普遍采用了电子控制技术，可以说今后汽车发展主要以机电一体化。汽车上广泛采用的电子控制点火系统主要有电子控制燃油喷射系统、电子控制点火系统、电子控制自动变速器、电子控制防滑（ABS/ASR）控制系统、电子控制悬架系统、电子控制动力转向系统、车辆动力学控制系统、安全气囊系统、主动安全带系统、电子控制自动空调系统、导航系统还有GPS等。有了这些系统汽车响应敏捷，使用功能强，可靠性高，既保证发动机动力又降低燃油的消耗，而且又满足排放法规的标准。
汽车是现代人必不可少的交通工具。而电动汽车给我们带来无限乐趣外还能给我们劳累一天的身心得以
放松。就拿自动变速器来说吧，汽车在行驶时，可以不踩离合器踏板，就可以实现自动换档而发动机不会熄火，这样有效的提高驾驶方便性减轻驾驶员的疲劳强度。自动变速器主要由液力变矩器、齿轮变速器、油泵、液压控制系统、电子控制系统、油冷却系统等组成。电子控制的悬架主要是用来缓冲路面对车身的冲击力以及减少振动保证汽车平顺性和操纵稳定性。当汽车行驶在不平坦的道路时汽车能能根据底盘和路面高度自动调整。当车高比设置的高度低时，就向气室或油缸充气或充油。如果是相反，就放气或泻油。从而保证汽车的水平行驶，提高行驶稳定性。可变力动力转向系统因能显著改变驾驶员的工作效率和状态，所以在电动汽车上广泛使用。VDC对汽车性能有着至关重要的作用它能根据需要主动对车轮进行制动来改变汽车的运动状态，使汽车达到最佳的行驶状态和操纵性能，并增加了汽车的附着性，控制性和稳定性。除了这些之外4WS、4WD的出现大大提高了电动汽车的价值与性能同步提升。ABS具有减少制动距离并能保持转向操作能力有效提高行驶方向的稳定性同时减少轮胎的磨损。安全气囊的出现在很大程序上保护了驾驶员和乘客的安全，大大降低汽车在碰撞时对驾驶员和乘客的缓冲，以过到保护生命安全的目的。
智能电子技术在汽车上得以推广使得汽车在安全行驶和其它功能更上一层楼。通过各种传感器实现自动驾驶。除些之外智能汽车装备有多种传感器能充分感知交通设施及环境的信息并能随时判断车辆及驾驶员是否处于危险之中，具备自主寻路、导航、避撞、不停车收费等功能。有效提高运输过程中的安全，减少驾驶员的操纵疲劳度，提高乘客的舒适度。当然蓄电池是电动汽车的关键，电动汽车用的蓄电池主要有：铅酸蓄电池、镍镉蓄电
池、钠硫蓄电池、钠硫蓄电池、锂电池、锌―空气电池、飞轮电池、燃料电池和太阳能电池等。在诸多种电池中，燃料电池是迄今为止最有希望解决汽车能源短缺问题的动力源。燃料电池具有高效无污染的特性，不同于其他蓄电池，其不需要充电，只要外部不断地供给燃料，就能连续稳定地发电。燃料电池汽车(FCEV)具有可与内燃机汽车媲美的动力性能，在排放、燃油经济性方面明显优于内燃机车辆。
随着计算机和电子产品不断开级换代，电动汽车技术也在日趋成熟与完善，使得驾驶更安全、方便、灵活、舒适。现在，电动汽车离普通消费者的距离还很遥远，只有少数人在赶赶时髦而已。电动汽车真正能够与传统的燃油汽车相竞争，今后汽车市场终会被电动汽车和智能汽车所取代。这只是时间性的问题这一天终究会来到的。ABS、GPS、4WS、4WD 以及各种新时代的电子产品与现代高性能汽车默契组合、绝妙搭配，带给我们无与伦比的精准驾驶舒适性和行驶安全性。
1、变速器的作用
发动机的输出转速非常高，最大功率及最大扭矩在一定的转速区出现。为了发挥发动机的最佳性能，就必须有一套变速装置，来协调发动机的转速和车轮的实际行驶速度。变速器可以在汽车行驶过程中，在发动机和车轮之间产生不同的变速比，通过换挡可以使发动机工作在其最佳的动力性能状态下。变速器的发展趋势是越来越复杂，自动化程度也越来越高，自动变速器将是未来的主流。
2、变速器的型式
汽车自动变速器常见的有三种型式：分别是液力自动变速器 (AT)、机械无级自动变速器(CVT)、电控机械自动变速器(AMT)。目前应用最广泛的是AT，AT几乎成为自动变速器的代名词。
AT是由液力变扭器、行星齿轮和液压操纵系统组成，通过液力传递和齿轮组合的方式来实现变速变矩。其中液力变扭器是最重要的部件，它由泵轮、涡轮和导轮等构件组成，兼有传递扭矩和离合的作用。汽车变速箱
与AT相比，CVT省去了复杂而又笨重的齿轮组合变速传动，而是两组带轮进行变速传动。通过改变驱动轮与从动轮传动带的接触半径进行变速。由于取消了齿轮传动，因此其传动比可以随意变化，变速更加平顺，没有换挡的突跳感。
AMT和液力自动变速器（AT）一样是有级自动变速器。它在普通手动变速器的基础上，通过加装微电脑控制的电动装置，取代原来由人工操作完成的离合器的分离、接合及变速器的选挡、换挡动作，实现自动换挡。
3、汽车变速器一般结构
3.1.简单式变速器的基本结构：由壳体、传动部分和操纵部分组成。
3.1.1.壳体：壳体是基础件，用以安装支承变速器全部零件及存放润滑油。其上有
安装轴承的精确镗孔。变速器承受变载荷，所以壳体应有足够的刚度，内壁有加强，形状复杂，多为铸件(材料为灰铸铁，常用HT200)。
为便于安装，传动部分和操纵部分常做成剖分式，箱盖与壳体用螺栓联接并可靠定位。壳体上有加油、放油口，油面检查尺口，还应考虑散热。
3.1.2.传动部分：是指齿轮、轴、轴承等传动件。轴的几何尺寸通过强度、刚度计算确定。因主要决定于刚度，而碳钢与合金钢弹性模量近乎相等，所以一般用碳钢(常用45钢)。只有齿轮与轴制成一体或轴载荷严重才用合金钢。轴与齿轮多为花键联接(对中性好，能可靠传递动力，挤压应力小等)。轴的花键部分和放轴承处经表面淬火处理。轴多用滚动轴承支承，润滑简单，效率高、径向间隙小，轴向定位应可靠。润滑方式多用飞溅(υ>25m／s，只要粘度适宜可甩到壁上)。
3.1.3.操纵部分：主要零件位于变速器盖内。
4、组成式变速器结构特点：
简单式变速器有效率高、构造简单使用方便钧优点矿但档数少，i变化范围小(牵引力、速度范围小)，只宜在档数不多的某些车工采用。若增加i的范围，则使变速器尺寸加大，轴跨度增加，为了既增加档
数又不使轴跨度过大，可采用组成式变速器。所谓组成式变速器，通常由两个简单式变速器组合而成，其中档数较多的称为主变速器，较少的称为副变速器。
4.1.组成式变速器的优点：
4.1.1.可以减少齿轮个数，而且档数越多减少齿轮个数的优点愈明显。同简单式变速器相比，它可缩短轴的长度，减少整个变速器的外部尺寸和重量，并且能方便地得到不止一个倒档。所以当前进档数超过六个档时，几乎都用组成式变速器。
4.1.2.传动：比变化率Ω大：若主变速器传动比变化率Ωzu=3，副变速器Ωfu=4则Ω=12；若使简单式变速器Ω=12，结构往往很难合理。
4.2.组成式变速器的缺点：
4.2.1.档组间传动比有对应关系，不易使每档的2，(速度及牵引力)都很理想。
4.2.2.换档操纵麻烦，有时要操纵两个变速部分，若为插花换档还不便记忆。
为了减少操纵动作，最好能顺序换档。为此要求重视档次编排十使第灭档组传动比全部大于第11档组，达到多数相领排档的变换只需操纵主变速的目的，这样才最为方便。
5、中国汽车变速器市场
中国汽车变速器市场正处于高速发展期。2007年中国汽车销售879.15万辆，2008年汽车产销量将突破900万，2010年汽车销售规模将达到1263万辆。在汽车行业市场规模高速增长的情况下，中国变速器行业面临着重大机遇。2006年我国汽车变速器市场规模达300亿元人民币，并且以每年超过20%的速度增长，预计2010年有望达到600亿元
Motors and gearboxes
As the world energy crisis, and the war and the energy consumption of oil -- and are full of energy, in one day, someday it will disappear without a trace. Oil is not in resources. So in oil consumption must be clean before finding a replacement. With the development of science and technology the progress of the society, people invented the electric car. Electric cars will become the most ideal of transportation.
In the development of world each aspect is fruitful, especially with the automobile electronic technology and computer and rapid development of the information age. The electronic control technology in the car on a wide range of applications, the application of the electronic device, cars, and electronic technology not only to improve and enhance the quality and the traditional automobile
electrical performance, but also improve the automobile fuel economy, performance, reliability and emissions purification. Widely used in automobile electronic products not only reduces the cost and reduce the complexity of the maintenance. From the fuel injection engine ignition devices, air control and emission control and fault diagnosis to the body auxiliary devices are generally used in electronic control technology, auto development mainly electromechanical integration. Widely used in automotive electronic control ignition system mainly electronic control fuel injection system, electronic control ignition system, electronic control automatic transmission, electronic control (ABS/ASR) control system, electronic control suspension system, electronic control power steering system, vehicle dynamic control system, the airbag systems, active belt system, electronic control system and the automatic air-conditioning and GPS navigation system etc. With the system response, the use function of quick car, high reliability, guarantees of engine power and reduce fuel consumption and emission regulations meet standards.
The car is essential to modern traffic tools. And electric cars bring us infinite joy will give us the physical and mental relaxation. Take for example, automatic transmission in road, can not on the clutch, can achieve automatic shift and engine flameout, not so effective improve the driving convenience lighten the fatigue strength. Automatic transmission consists mainly of hydraulic torque
converter, gear transmission, pump, hydraulic control system, electronic control system and oil cooling system, etc. The electronic control of suspension is mainly used to cushion the impact of the body and the road to reduce vibration that car getting smooth-going and stability. When the vehicle in the car when the road uneven road can according to automatically adjust the height. When the car ratio of height, low set to gas or oil cylinder filling or oil. If is opposite, gas or diarrhea. To ensure and improve the level of driving cars driving stability. Variable force power steering system can significantly change the driver for the work efficiency and the state, so widely used in electric cars. VDC to vehicle performance has important function it can according to the need of active braking to change the wheels of the car, car motions of state and optimum control performance, and increased automobile adhesion, controlling and stability.
Besides these, appear beyond 4WS 4WD electric cars can greatly improve the performance of the value and ascending simultaneously. ABS braking distance is reduced and can keep turning skills effectively improve the stability of the directions simultaneously reduce tyre wear. The airbag appear in large programs protected the driver and passenger's safety, and greatly reduce automobile in collision of drivers and passengers in the buffer, to protect the safety of life.
Intelligent electronic technology in the bus to promote safe driving and that the other functions. The r
ealization of automatic driving through various sensors. Except some smart cars equipped with multiple outside sensors can fully perception of information and traffic facilities and to judge whether the vehicles and drivers in danger, has the independent pathfinding, navigation, avoid bump, no parking fees etc. Function. Effectively improve the safe transport of manipulation, reduce the pilot fatigue, improve passenger comfort. Of course battery electric vehicle is the key, the electric car battery mainly has: the use of lead-acid batteries, nickel cadmium battery, the battery, sodium sulfide sodium sulfide lithium battery, the battery, the battery, the flywheel zinc - air fuel cell and solar battery, the battery. In many kind of cells, the fuel cell is by far the most want to solve the problem of energy shortage car. Fuel cells have high pollution characteristics, different from other battery, the battery, need not only external constantly supply of fuel and electricity can continuously steadily. Fuel cell vehicles (FCEV) can be matched with the car engine performance and fuel economy and emission in the aspects of superior internal-combustion vehicles.
Along with the computer and electronic product constantly upgrading electric car, open class in mature technology and perfected, that drive more safe, convenient and flexible, comfortable. Now, the electric car from ordinary consumers distance is still very far away, only a few people in bandwagon. Electric cars with traditional to compete in the market, the car will was electric cars and i
ntelligent car replaced. This is the question that day after timing will come. ABS, GPS, and various new 4WD 4WS, electronic products and the modern era, excellent performance auto tacit understanding is tie-in, bring us unparalleled precision driving comfort and safety of driving.
1、The role of transmission
The output of the engine speed is very high, maximum power and maximum torque at a certain speed area. Engine in order to exert the best performance, it is necessary to have a variable-speed devices, to coordinate the engine speed and the actual wheel speed. Transmission process in the car, in between the engine and the wheels have a different gear ratio, by shifting the engine can work at their best performance of state power. Transmissions are the development trend of more and more complex, increasingly high degree of automation, automatic transmission will be the mainstream of the future.
2、Transmission type