In this era when 9AT or even 10AT vehicles are running all over the street, 6AT gearbox seems to lag behind by more than one level, but this is a gap that Chinese and foreign automobile circles have to admit. Although you can't catch up with foreign companies at once, you can get 100 points with 60 points, which is enough. No, Zotai said to Dong 'an, "I want as much as you have!" Let's see what kind of gearbox this is.
● Why did Dongan develop 6AT gearbox?
Maybe you don't know much about Dongan gearbox, but when it comes to 4G 1 and 4G9 Mitsubishi engines produced by Dongan, you may be familiar with them. Powertrain has always been a shortcoming of China automobile industry. At the early stage of brand development in China, most automobile enterprises adopted Dongan Mitsubishi's machines. Dongan is located in Harbin Development Zone, with a building area of114000m2 and over 300 employees, mainly producing engines and gearboxes. 202 1, after the share reorganization, Dongan began to belong to Changan Automobile. By the way, Dongan is currently responsible for manufacturing the Blue Whale 2.0T engine in changan CS95.
With the continuous improvement of automobile manufacturing level, China brand automobile enterprises in the early 20th century urgently needed the application of automatic transmission. At that time, they could only spend money on foreign gearboxes such as Aisin, ZF and Getrag. However, due to various reasons such as capacity problems, China brand car companies are often restricted. Therefore, this has inspired a group of enthusiastic automotive engineers, who are determined to build their own automatic transmission in China.
In the choice of automatic gearbox direction, most car companies bypass AT gearbox and choose to build DCT dual clutch gearbox or CVT continuously variable gearbox. The reason is that at transmission is the most difficult and requires a lot of time and energy. Obviously, China brand car companies that were not mature enough at that time would not foolishly put their chips on this difficult and dangerous road. Therefore, compared with DCT and CVT gearbox, AT gearbox is a weak field for us.
Nowadays, besides BYD, SAIC, GAC and JAC, many China brand automobile companies have chosen DCT gearboxes. Have come up with their own DCT products. When most China brand car companies bypass the research and development of AT gearbox, where does Dong 'an's confidence in building 6AT come from?
● What is this 6AT gearbox?
Compared with the original Mitsubishi 4AT gearbox, the fuel consumption of this 6AT gearbox is reduced by 10%, and it supports multiple driving mode selection functions, automatic engine start-stop function, hybrid power system and four-wheel drive system structure. The maximum torque is 280n·m, which can match most current 1.5T engines. The technology is not outdated and can basically meet the transmission requirements of most China brand vehicles.
Dong 'an set a relatively compact volume from the beginning. The length, width and height of mass-produced 6AT are 345mm, 5 12mm and 388mm respectively. The aluminum alloy shell is adopted, and the weight is kept within 82kg, and the lightweight level is good. Compared with mazda 6AT and GM 6AT that we dismantled before, the transmission ratio of Dongan 6AT is more balanced, and the transmission ratios of all gears are between them.
Compared with foreign established gearbox companies such as Aisin and ZF, Dongan can only be regarded as an entry-level player in the field of AT gearbox, and it can't take an advantage in technical level and adjustment experience, so Dongan can only score 60 points and 100 points to ensure the most basic smoothness and reliability of automatic gearbox. So how did Dongan build this 6AT gearbox? Let's talk about its production line first.
6AT gearbox production/real vehicle experience
● How is Dongan 6AT produced?
-Machining of blank parts
The reliability of gearbox is closely related to manufacturing technology and production quality. In order to build this 6AT gearbox, Dongan invested1800 million yuan in product research and development, and built a brand-new gearbox production line.
Although the domestic machining industry has developed for many years, there is still a certain gap between the machining accuracy and consistency control abroad, which is also the key link of AT gearbox. In the gearbox structure, the highest accuracy requirement should be the gearbox valve body, because small size errors or burrs may affect the shift control mechanism, resulting in oil leakage, smooth shift and other problems.
What should I do if the transmission valve body has burrs? The cleaning machine imported from Dong 'an is also from German MTM company. Inside the cleaning machine, the surface of the gearbox valve body will be washed for 45Mpa. What concept? This is equivalent to a pressure of 450 tons 1 m2, so cleaning with a cleaning machine can basically solve the burr problem.
-Gear box assembly
The final assembly line of gearbox is the most critical step, which requires stricter production environment. In order to ensure the assembly quality of products, the air temperature in the workshop must be kept between 20℃ and 25℃, and kept in a sealed and dust-free room. If you want to enter the gearbox assembly workshop, you must wear work clothes and shoe covers and clean them in the dust removal room.
The gearbox assembly workshop needs several sub-assembly lines, such as clutch, planetary carrier, gearbox valve body, electrical equipment, testing station, etc., which shows the complexity of AT gearbox parts.
This 6AT gearbox has several sets of clutches. By locking different clutches, planetary gear sets can be combined in different ways to match the transmission ratio of the required gear. On the clutch assembly line, Dong 'an adopts multi-disc clutch. There are about 3-4 clutch plates depending on the torque. The more clutch plates, the easier it is to weaken the shift impact and the better the shift ride.
When the planetary gear sets and multi-disc clutches of the transmission are assembled on the housing, they eventually need to be combined with the transmission valve body assembly. Due to the large number of solenoid valves, control elements and other parts of the gearbox valve body assembly, a separate packaging line is set for it. Undoubtedly, the price will be an important factor for China brand car companies to choose Dongan. Compared with the current Aisin 6AT, it has no small advantage in the purchase price. Many parts in the valve body come from Japanese and Korean enterprises, so with the further localization of parts in the later period, it is believed that the cost of the valve body will still decrease to some extent.
Based on the support of mainstream foreign suppliers and advanced processing equipment, Dongan expects the annual output of 6AT gearboxes to be around 30,000 units this year. Because the production capacity can't reach a high level, the supply of 6AT products is in short supply at present. Zotye said "give as much as you need", indicating that Dongan 6AT has enough recognition. But what is the actual performance of this 6AT? I don't think it is possible to draw a conclusion without personal experience.
● How about driving Zotye T600 Coupe equipped with Dongan 6AT?
In order to have a more comprehensive understanding of this 6AT gearbox, we personally tested and experienced the Zotye T600 Coupe equipped with it. Zotye matched its own 1.5T engine for this 6AT gearbox. Because the bearing torque of Dongan 6AT gearbox can reach 280n·m, it is basically no problem to match Zotye 1.8T engine in the later stage.
Due to the limitation of space and time, we didn't carry out standard acceleration, brake test and high-speed experience. Please look forward to our more comprehensive and professional test drive in the future. Generally speaking, this 6AT gearbox has not exposed any obvious defects. I believe that in the future, as long as it is used for a long time to ensure sufficient reliability, more China brand car companies will definitely say "how much is needed".
● Summary
As the old saying goes, "Whether it is a mule or a horse, pull it out for a walk", the performance of Dongan's 6AT gearbox may soon be verified by the market. The result of long-term use will determine Dongan's position in the field of automatic transmission in the future, and may also trigger the re-selection of automatic transmission by China brand car companies in the future. @20 19