What is the basic knowledge of the gearbox?
Gearbox parts generally have complex structure and high structural rigidity. They are mainly used to support other parts (such as bearing seats, gear boxes, machine tool beds, etc.). They generally bear static and dynamic loads with low stress. Therefore, it usually requires low strength and toughness of the material, but it should have good casting performance and shock absorption.
Gearbox parts generally have complex structure and high structural rigidity. They are mainly used to support other parts (such as bearing seats, gear boxes, machine tool beds, etc.). They generally bear static and dynamic loads with low stress. Therefore, it usually requires low strength and toughness of the material, but it should have good casting performance and shock absorption. The following describes the basic knowledge of the gearbox:
1. Why do you need a gearbox?
Cars have driving needs such as starting, uphill and high-speed driving. During this period, the torque required to drive the car is different, which cannot be achieved only by the engine. Since the range of torque directly output by the engine is small, the range of torque required by the vehicle is large, so it is necessary to use the transmission to achieve many different driving functions. In addition, if the car needs to reverse, a gearbox must also be used.
2. Why can the gearbox change the speed?
There are many different gears in the gearbox. By combining different gears, the engine torque and speed can be adjusted. Low torque can be replaced with high speed, and low speed can be replaced with high torque. The function of the transmission is mainly manifested in three aspects:
1) Change the transmission ratio, expand the range of torque and speed of the driving wheels, meet the traction requirements of different driving conditions, make the engine work under favorable conditions as much as possible, and meet the possible driving speed requirements.
2) Under the condition that the engine steering remains unchanged, it can meet the needs of reversing.
3) In order to achieve the neutral position and interrupt the power transmission, when the engine is started, idling, the vehicle is shifted or needs to be stopped to obtain power output, the transmission can stop the power transmission to the driving wheels without power output.
3. What types of gearbox are there?
Manual transmission (MT) is to manually pull the shift lever to change the gear engagement position and transmission ratio in the transmission, so as to achieve the purpose of shifting. The automatic transmission automatically changes the speed according to the degree of the accelerator pedal and the change of the vehicle speed. There are four common types:
1) Electromechanical automatic transmission (AMT) is an automatic control system based on mechanical transmission, which realizes the goal of automatic shifting. AMT has a simple structure and high shifting efficiency, which is usually important for low-cost, economical vehicles.
2) Automatic hydraulic transmission (AT) is a transmission device that realizes speed change and torque change through hydraulic transmission and gear combination. Its great feature is smooth shifting, mature and reliable technology.
3) The mechanical continuously variable transmission box (CVT) transmits power through the transmission belt and the tapered pressure plate with variable groove width, which can realize the continuous change of the transmission ratio of the transmission shaft. Although the overall performance is good, unlike AT and MT, they can withstand a larger engine torque output.
4) The dual clutch gearbox (DSG) works alternately through two sets of clutches. Although the ride comfort is slightly worse at low speeds, the shift speed is quite fast and is widely used in various models.