Both said that the double departure is not good, why the big car enterprises still grab on the top?

　

       　　

Above this change, the old driver Qingjushulu, naturally a little to adapt, but not TCU, it will only be in accordance with established procedures to continue to control the clutch, the same, the myriads of changes road conditions and the owners driving habits TCU won't understand. The problem is that in the stop and stop traffic jam, the double clutch is always in the "half clutch state" in the clutch control part, so it is easy to overheat, resulting in a series of failures. While another major criticism of the sense of frustration, after all, is a dual clutch manual transmission was born, because there is no automatic torque converter buffer, low bit shift are inherently difficult to offset the setback.
What's the solution?
Some engineers have proposed to join the clutch pedal to solve the problem of "half clutch and dry burning". However, even if the proposal is simply IQ arrears, who would be willing to pay more to buy a "manual shift"? And the proposal is based on the AMT sequential transmission of the F1 racing car, which is only suitable for a first gear.
Honda has a set of a torque converter (from the automatic transmission, the equivalent of an automatic "clutch", with the characteristics of flexible transmission) 8 speed dual clutch gearbox in the 2015 Acura TLX sales, they hope to reduce the dual clutch shift when the setback, result is put on the market after dozens of complaints.
Wet double clutch oil lubrication and cooling, better than dry double clutch heat dissipation, but still can not be cured, and larger volume and higher cost. It needs regular maintenance and replacement of oil as automatic transmission.
By the way, the way, the Americans are not very love double clutch, but according to their feedback, most is actually because of gear up... Don't love double clutch fast dual clutch problem whether independent brand and foreign brands have a short period of time, but also can effectively eradicate.
  

When did you know when the "double clutch gearbox" was the first time? In 2010, known as the "golden combination of power", equipped with 1.4L TSI engine speed +6 DSG dry dual clutch gearbox new Sagitar listed. At this time, the double clutch gearbox began to formally enter the domestic ordinary families. However, the year is menacing new technology, now they are all the negative news ridden around it which is seen as one falls, another rises. Where is the problem of double clutch? Why are there so many problems, and most car companies are willing to use it?
What is double separation?
Although the double clutch is "long" like an automatic block, it is essentially improved on the basis of a manual transmission. The double clutch has two pairs of clutch and two power output shafts (twice as much as the manual ones), and the two clutch controls different gears respectively, which is responsible for meshing different gears. The 6 speed dual clutch gearbox as an example, it will be divided into 6 stalls for odd and even gear gear, when the vehicle is in a high, a two block is already ready to hang into the switch, and then the gear switch and so on, the benefits of doing so is that greatly improves the shifting time. The transmission efficiency is greatly improved, but also more fuel-efficient theory.
Secondly, because of upgrading the manual transmission, compared with the automatic transmission, its structure is relatively simpler and occupies less space. Compared with the CVT gearbox, double clutch can also withstand relatively higher torque output.
Is it ineffective or is it poor in quality?
Although in theory, the dual clutch gearbox an advantage, but found the actual performance of its people do not buy it from the feedback of the past few years but, even with the dual clutch gearbox considerable trouble during use. Where is the problem?
The old driver in the driving manual models according to the actual conditions, their needs and other aspects of freedom master shifting time and half linkage, and manual upgrade version of the dual clutch is completely rely on the computer program TCU to make a decision, this also causes the human like to make the appropriate judgment in many cases under the.
For instance。 In the case of half clutch and starting, the friction plate and the press disc will have violent friction, which can lead to the normal wear of the friction plate. If things go on like this, the gap between the friction plate and the pressure plate will gradually increase, this is reflected in the loss of normal operation of the clutch pedal "clutch" becomes a little bit high - the original assumption of older drivers only loose the clutch pedal to a half, the pressure plate and the friction plate with friction wear; now, and a big gap between the pressure plate. The clutch pedal to a little more than half of the loose, pressure plate and friction plate to complete with.　　

So why do you insist on it?
The first reason is to reduce fuel consumption: according to the newly revised "fuel consumption limit of passenger cars" by the Ministry of industry and commerce, by 2020, the average fuel consumption of all the cars produced by all vehicle manufacturers will decrease from 6.9L/100km (third stage) in 2015 to 5.0L/100km (fourth stage). This is also the reason many car companies choose the dry double clutch. In the case of lower cost, the transmission efficiency is higher than the wet double clutch, and the oil is more efficient.
The other is the purchase cost. Although the automatic transmission is mature and stable, the price is not cheap. The current mainstream automatic gearbox market maker ZF/ has basically been carved up such Aisin patent barriers, high, expensive products. Although big international plants like BMW are willing to pay for their own fist products, it hesitates when it comes to the 1, 2, and X1.
The dual clutch is no such trouble: lower the threshold, not only can choose their own R & D, can also purchase, the price is still relatively cheap; at the same time, the most important is that in the dual clutch, the world car prices are on the same starting line, there is no automatic gearbox that exaggerated the strength of the gap of course... We are still friends, not to mention PDK.
In the end, the current problem of the dual clutch transmission is in fact a technical bottleneck. Although it is not broken, but restrict the technology advantage, theory of double clutch and the cost of the environment or to attract major automobile manufacturers continue to participate in them. In fact, the development process of the dual clutch automatic transmission and now have very similar, in the early after the technology is mature, product instability, high failure rate, but with the continuous development of future technology, dual clutch will overcome technical bottlenecks and realize efficient and practical.
Nevertheless, we can count on this point is expected to come, not by some unscrupulous manufacturers as white mice hurt.