一、AT（液力自动变速箱）

1、 AT (Hydraulic Automatic Transmission)

和手动档相比，液力自动变速箱（AT）在结构和使用上有很大的不同。手动变速箱主要由齿轮和轴组成，通过不同的齿轮组合产生变速变矩，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达到变速变矩。但是由于各种辅助机构的自动换档能满足行驶上的多种需要，例如停泊、后退等，所以在自动档上还设有干预装置即手动拨杆，标志P(停泊）、R(后档)、N(空档)、D(前进)，另在前进档中还设有“2”和“1”的附加档位，用以起步或上斜坡之用。由于将其变速区域分成若干个变速比区段，只有在规定的变速区段内才是无级的，因此AT实际上是一种介于有级和无级之间的自动变速器。

Compared to manual transmission, hydraulic automatic transmission (AT) has significant differences in structure and usage. The manual transmission is mainly composed of gears and shafts, which generate variable speed and torque through different gear combinations. The AT is composed of a hydraulic torque converter, planetary gears, and a hydraulic control system, which achieves variable speed and torque through hydraulic transmission and gear combination. However, due to the various auxiliary mechanisms that can meet various driving needs, such as parking, reverse, etc., there is also an intervention device on the automatic gear, which is a manual lever, marked P (parking), R (rear gear), N (neutral), D (forward). In addition, there are additional gears of "2" and "1" in the forward gear for starting or climbing slopes. Due to dividing its transmission area into several transmission ratio ranges, the AT is only continuously variable within the specified transmission range. Therefore, the AT is actually an automatic transmission that falls between a stepped and a continuously variable transmission.

AT的优点：AT不用离合器换档，档位少变化大，连接平稳，因此操作容易，既给开车人带来方便，也给坐车人带来舒适。

Advantages of AT: AT does not require a clutch to shift gears, with few gear changes and smooth connections, making operation easy. It not only brings convenience to drivers but also comfort to passengers.

AT的缺点：首先对速度变化反应较慢，没有手动变速箱灵敏，因此许多玩车人士喜欢开手动变速箱车。第二是费油，传动效率低而且变矩范围有限，不过近年不少车型都在自动档里面引入了电子控制技术，这方面的问题因而有所改善，但终究还是比不上手动档经济。第三是机构复杂，修理困难。在液力变扭器内，高速循环流动的液压油会产生高温，所以要用指定的耐高温液压油，也就是平常所说的“波箱油”，另外如果汽车因蓄电池缺电不能启动，不能用推车或拖车的方法启动。如果拖运故障车的话，还要注意使驱动轮脱离地面，以保护自动变速箱齿轮不受损害。

Disadvantages of AT: Firstly, it has a slow response to speed changes and is not as sensitive as manual transmissions, so many car enthusiasts like to drive manual transmissions. The second issue is fuel consumption, low transmission efficiency, and limited torque range. However, in recent years, many models have introduced electronic control technology in automatic transmission, which has improved this issue. However, in the end, it is still not as economical as manual transmission. The third is the complexity of the mechanism and difficulty in repair. In a hydraulic torque converter, the high-speed circulating hydraulic oil will generate high temperatures, so a specified high-temperature resistant hydraulic oil, commonly known as "gearbox oil", should be used. In addition, if the car cannot start due to a lack of battery power, it cannot be started by pushing or towing. If towing a faulty vehicle, it is also important to ensure that the drive wheels are off the ground to protect the automatic transmission gears from damage.

二、CVT（机械无级自动变速箱）

2、 CVT (Mechanical Continuously Variable Transmission)

现在的广本飞度，旗云还有别的一些车型都应用了CVT变速箱。它采用传动带和可变槽宽的棘轮进行动力传递，即当棘轮变化槽宽肘，相应改变驱动轮与从动轮上传动带的接触半径进行变速，传动带一般用橡胶带、金属带和金属链等。CVT属于真正无级变速箱。

The current Guangben Fit, Qiyun, and other models all use CVT transmissions. It uses a transmission belt and a variable groove width ratchet for power transmission, that is, when the ratchet changes the groove width elbow, the contact radius between the driving wheel and the driven wheel on the transmission belt is correspondingly changed for speed change. The transmission belt is generally made of rubber belts, metal belts, and metal chains. CVT belongs to true continuously variable transmission.

CVT的优点：重量轻，体积小，零件少，与AT比较具有较高的运行效率，油耗也较低。

The advantages of CVT include light weight, small size, fewer parts, higher operating efficiency compared to AT, and lower fuel consumption.

CVT的缺点：传动带很容易损坏，不能承受较大的载荷，目前还不能应用在大排量的汽车上，普遍应用在2升以下的车型之中，譬如奥迪的Multitronic、本田的CVT、菲亚特的Speedgear等等。

Disadvantages of CVT: The transmission belt is easily damaged and cannot withstand large loads. Currently, it cannot be applied to large displacement cars and is generally used in models below 2 liters, such as Audi's Multitronic, Honda's CVT, Fiat's Speedgear, and so on.

三、AMT（电控机械自动变速箱）

3、 AMT (Electronic Mechanical Automatic Transmission)

是在总体传动结构不变的情况下通过加装微机控制的自动操纵系统来实现换档的自动化。因此AMT实际上是由一个机器人系统来完成操作离合器和选档的两个动作。目前的手自一体化自动档基本上都是这种类型，奇瑞的QQ就有AMT的车型。

It is achieved through the installation of a microcomputer controlled automatic control system to achieve gear shifting automation while keeping the overall transmission structure unchanged. Therefore, AMT is actually completed by a robot system to operate the clutch and select gears. At present, most of the manual automatic transmission systems are of this type, and Chery's QQ has AMT models.