Automatic transmission

Automatic transmission

I did my homework to briefly review the forgotten practical knowledge of the vehicle’s automatic transmission/transaxle to prevent dementia.

The transmission of the car is not possible to move a vehicle with a stopped torque curve according to the speed of the engine, so a deceleration ratio is created that decelerates through gears but significantly changes torque. The tire at the end makes it a large torque that can easily start the vehicle, and then gradually increases the speed using an accelerator, while at that speed, it helps comfortable road driving with sufficient torque

The homework for the manual transmission is already brief, but this time, we will solve the automatic transmission using more new technologies than the manual transmission one by one.

With the development of the automobile industry, automobile manufacturers develop automatic transmissions with slightly different technologies, and new transmissions are introduced every year when new cars are announced. The key point of the new technology is that devices with good shifting performance have developed remarkably while reducing weight and increasing energy efficiency when shifting.

In 2011, when I stepped down from my job, there were not many automatic transmission devices using new technologies, so I learned a lot by collecting and reading data while reviewing.

If you briefly describe these different types of automatic transmissions from new technology applications

Intelligent manual transmission (IMT) : An intelligent manual transmission device whose structure is similar to that of a manual transmission, but without a clutch pedal in the driver’s seat, an automatic transmission device in which the transmission computer (TMC) appropriately selects and accelerates clutch and gear according to road conditions
https://www.youtube.com/watch?v=e-RUoEqAGHI

CVT (Continuously Variable Transmission): There are two representative practical forms, also called continuously variable transmissions.

1), belt type: The power is transmitted by connecting the variable width pulley on the input axis and the variable width pulley on the output axis in one of rubber belt, metal chain, and metal belt. When the vehicle starts, the width of the input shaft pulley is widened and the width of the output pulley is reduced to increase deceleration and torque, and when the accelerator is stepped on to increase speed while driving, the width of the input pulley is reduced, and the width of the output pulley is widened to accelerate and reduce torque, which is applied to relatively small passenger cars. See Figure https://www.youtube.com/watch?v=PEq5_b4LWNY

2), toroidal type: An automatic transmission with a variable angle toroidal roller between the conical input disk and the conical output disk, changing the angle within the input/output disk of the toroidal roller to change the speed deceleration ratio of the input disk without permission and transmit it to the output disk. See Figure of an automatic transmission that uses a special lubricant that lubricates the disk and the toroidal roller while minimizing friction wear
https://www.youtube.com/watch?v=nayVR2PAWHo3, DCT (double clutch transmission): It has a manual transmission structure but on a flywheel Two separate clutches are placed in the attached clutch assembly and connected to each clutch by separate input shafts, but the input shaft is concentric, i.e., the shaft inside the pipe is connected by the shaft for clutch number one, and the shaft for clutch number two is used as an external pipe with built-in shaft number one, and each of these two input gears is equipped with each input gear continuously meshed The first shaft input gear has a counter shaft input gear with 1, 3, and 5 gears A counter shaft with 2, 4, and 6 gears is always connected to the input gear to which the second clutch is connected, and the output shaft that is always engaged and idling with the input shaft and the output shaft supported by the bearing has the 1,2,3,4,5,6 output gear and the synchro gear. The automatic transmission selection allows the computer to automatically select the synchro mechanism according to the engine output, car load condition and road conditions, see Figure of the automatic transmission

https://www.youtube.com/watch?v=lFAtc-zOKZs https://www.youtube.com/watch?v=t8aGgSbtoJE

4. Meteor Gear-based automatic transmission: It is mainly composed of multiple planetary gears connected or composed of Simpson gear and Lavigneaux gear, which are composite planetary gears. The automatic transmission process is an automatic transmission that selectively fixes a specific gear part and moves the rest of the gears to change the power flow path, which is still widely used today Automatic transmissions, which were mainly handled during the field, fall under the planetary gear type, and it is common for automobile manufacturers to receive delivery from specific automatic transmission manufacturers and adopt them in their cars. Representative automatic transmission manufacturers include allison transmission, ZF transmission, and voice transmission. Currently, most automatic transmissions based on planetary gears are adopted and used the most, and technology development and facility improvement have progressed steadily to the point where you almost don’t feel the shift speed similar to an unauthorized transmission, so that you can gradually increase the gear speed to 4th, 5th, 6th, 8th, and 10th stages to increase power transmission efficiency and change smoothly