It is believed that even those who have a slight understanding of mechanics can understand that the role of the transmission system is to transmit power to drive vehicles. However, this is only the fundamental role of the transmission system. In fact, the important role of transmission system is "speed change".

　　来看看什么是传动系统。汽车靠驱动轮旋转来行驶，但发起机并不直接驱动驱动轮。发起机的动力经由变速器、差动齿轮、传动轴等传给驱动轮。这整套设备称作传动系统(驱动系统或者动力传输系统)。

　　First, let's look at what a transmission system is. The car runs by rotating the driving wheel, but the engine does not drive the driving wheel directly. The power of the engine is transmitted to the driving wheel through the transmission, differential gear, transmission shaft, etc. This whole set of equipment is called a transmission system (drive system or power transmission system).

　　济南自动变速箱维修

　　Maintenance of Jinan Automatic Transmission

　　什么传动系统的重要作用是“变速”呢?举例来说，记得骑着三轮车追不上自行车，而之所以会这样，主要缘由是三轮车不如自行车的速度快。此外，小孩子即便会骑三轮车，蹬起来也不容易，而自行车的话，小孩子也能随便蹬动。形成这种差别的缘由是变速功用。那为什么必需变速呢?简单地说是由于假如传动系统直接将发起机的转动信息停止传送的话，就没有足够的扭矩来驱动汽车行驶。因而，遭到发起机驱动力的传动系统要减少转动次数，增加扭矩，然后将之传送到驱动轮。

　　What is the important role of the transmission system? For example, remember that riding a tricycle can not catch up with a bicycle, and the main reason for this is that the tricycle is not as fast as the bicycle. In addition, even if a child can ride a tricycle, it is not easy to pedal, and if the bicycle, the child can pedal freely. The reason for this difference is the variable speed function. So why do we have to change gears? Simply because if the transmission system stops transmitting the information of the engine's rotation directly, there will not be enough torque to drive the car. Therefore, the drive system driven by the initiator needs to reduce the number of rotations, increase the torque, and then transmit it to the driving wheel.

　　济南自动变速箱维修厂家解说汽车从启动到高速行驶期间，速度不时变化，道路也有缓有陡。条件发作变化，变速办法也必需做出相应的调整，因而传动系统必需可以在不同变速形式之间互相切换。如今你明白了吗?假如传动系统不能停止“变速”来增加扭矩，仅靠发起机产生的动力是缺乏以驱动车辆的。

　　Jinan automatic transmission maintenance manufacturer explained that during the period from start-up to high-speed driving, the speed changes from time to time, and the road is slow and steep. When conditions change, the method of transmission must be adjusted accordingly, so the transmission system must be able to switch between different forms of transmission. Now you see? If the transmission system can't stop "changing speed" to increase the torque, the power generated by the engine alone is lacking to drive the vehicle.