The role of the gearbox: manual gearbox, automatic gearbox, continuously variable gearbox, dual-clutch gearbox, sequential gearbox.etc
Before understanding the structure of the gearbox, we must first know why a gearbox is needed and what its function is. According to different driving conditions, the speed and power of the vehicle need to be changed in a larger range. To achieve this, in addition to effective braking, the choice of gear is also very important. Therefore, change the transmission ratio to adapt to different driving. State is a major function of the gearbox. In addition, realizing reversing and using neutral to cut off power transmission without stalling are also reasons why gearboxes are widely used in the field of internal combustion engines.
The role of gearbox
1. Change the transmission ratio
Expand the range of torque and speed of the driving wheels to adapt to frequently changing driving conditions, and at the same time make the engine work under favorable conditions (higher power and lower fuel consumption).
2. Under the condition that the rotation direction of the engine remains unchanged, the car can be driven backwards.
3. Use neutral gear to interrupt power transmission so that the engine can be started and idle, and it is convenient for the transmission to shift gears or perform power output.
The role of gearbox
(1) Manual transmission
"Manual transmission is not a sign of low-end models." This position must be stated before introducing this type of gearbox. Models equipped with manual gearboxes require the driver's hands and feet to switch gears during driving, but some people also regard this direct communication with machinery as a pleasure.
The role of gearbox
Manual gearboxes are also divided into gears. We commonly have 5-speed manual gearboxes and 6-speed manual gearboxes. Of course, you must have heard some news about 7-speed manual gearboxes. This one comes from ZF The manual gearbox is assembled on the Porsche Carrera model. Later, we will have a special analysis article. What is certain is that the more gears, the tighter the gear ratios, the more comfortable power connections, and the better fuel economy and comfort performance at high speeds.
Let's first understand the working principle of the manual gearbox through the following simple structure model. The green part in the picture is the input shaft, which is connected to the engine through a clutch, and the power of the input shaft is transmitted to the output shaft in the yellow part through the gear of the intermediate shaft. At this time, the output shaft and the blue gear are not running synchronously. , Since the sleeve is located in the center of the two output shaft gears and is not combined with any one of the gears, it is neutral in this state. What is the state after it is put on the gear?
Use the shift lever to operate the shift fork to combine the sleeve with the first gear on the output shaft. At this time, under the action of the sleeve, the first gear and the output shaft run synchronously, completing the power transmission from the input shaft through the intermediate shaft. The process of final transmission to the output shaft to the wheels. Under normal circumstances, when pushing the shift lever into the gear, the driver needs to depress the clutch pedal first, and then lift the clutch pedal when the gear is ready. In addition, the clutch must be operated to interrupt the engine and the stop when starting and stopping. Power transmission between gearboxes.
Advantages and disadvantages of manual gearboxes
1. Shift gears with the goal of reducing fuel consumption.
2. The maximum power of the engine can always be used.
3. All driving conditions have corresponding shift points.
4. The shift point changes arbitrarily.
First of all, the manual transmission model is definitely not as comfortable as the automatic transmission model. It requires more physical effort from the driver. Of course, many people regard this as a driving pleasure, but if the traffic is rush hour, frequent movements will also affect it. This "pleasure" is gone. And its advantage lies in stable work and cheap maintenance. In addition to the regular replacement of manual transmission oil, the replacement of the clutch is a relatively large maintenance item for the manual gearbox of the family car.