What is the structure of powershift?

Powershift is equivalent to integrating the functions of two manual transmissions into one transmission. In a vehicle with manual transmission, when the driver wants to change from one gear to another, he first needs to step on the clutch pedal to make one clutch start working, disconnect the engine from the transmission and interrupt the power transmitted to the transmission. Then the driver selects a new gear with the gear lever, which is a process of moving the coupling sleeve from one gear to another gear with different sizes. Synchronizer works before meshing to make the linear velocity of tooth surface consistent and prevent tooth surface collision. Once the new gear is cut off, the driver releases the clutch pedal, which reconnects the engine with the transmission and transmits power to the wheels. Therefore, in the shift process of traditional manual transmission, the power transmission goes through the process of transmission-interruption-transmission, which will cause the phenomenon of "shift impact" or "torque interruption"

Compared with manual transmission, powershift uses two clutches, but there is no clutch pedal. The clutches are controlled by electronic system and hydraulic system, just like standard automatic transmission. In powershift, the clutches work independently, with one clutch controlling odd gears (such as 1, 3rd gear, 5th gear and reverse gear) and the other clutch controlling even gears (such as 2nd gear, 4th gear and 6th gear). Because the transmission controller engages the next sequential gear in advance according to the speed change, there will be no power interruption when shifting gears.

Double clutch transmission is mainly composed of double clutch, mechanical part transmission, automatic gear shifting mechanism and electronic hydraulic control system. The core part is the double clutch and two-shaft input shaft in the mechanical part transmission. This unique two-axis structure separates odd gears from even gears: unlike the traditional manual transmission which concentrates all gears on one input shaft, powershift distributes odd gears and even gears on two input shafts, that is, the outer input shaft is hollowed out, leaving embedded space for the inner input shaft. Take a 6-speed transmission as an example. Its internal input shaft is equipped with 1, 3 and 5 gears and reverse gear, and its external input shaft is equipped with 2, 4 and 6 gears, which can realize rapid gear shifting and maintain power transmission during gear shifting. The standard manual gearbox cannot do this because it must use a clutch to control all odd and even gears.