How Dual Clutch Transmissions Work - Simple Explanation
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- เผยแพร่เมื่อ 27 ก.ย. 2024
- How do dual clutch transmissions work? I explain how the system works, and why it is so successful at rapid gear changes. How it changes gears, and how the two clutches operate and transfer. Enjoy!
I should probably note that instead of having the bottom shaft as an output shaft, it would more than likely be a countershaft, having an extra gear at the end connecting to a third shaft (output). This would keep the engine and output rotating in the same direction. Regardless, this doesn't take away from how the system operates.
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Good explanation but damn dude, your production value in your newer videos is lightyears past your old ones.
lol he was still in his Alt Rock stage here..
super helpful, i understood in 30 seconds, also shoutout to your knees in the bottom of the frame.
@TheKIDDERz Thank you so much, it's good to know that people appreciate these as I put a lot of time into them. I don't understand why so many "explanation" videos have overlaying music, to me it's just distracting and pointless. Anyways, glad you enjoy my videos!
@lilaznmage15
End the youtube url in this: "watch?v=nbCe68ck6qg" or simply search "Fuel Injection" on my Channel.
Thanks for watching!
This kid properly knows what he's talking about.
Whenever we start a new subject at college, the first thing the teacher does is link us the relevant video on this channel.
Why? Because you explain things in such a simple way and illustrate it so well.
If you want to know how something works this guys videos will do it better than anything else.
Thanks for the kind words!
Engineering Explained they're well deserved! It should be me thanking you for helping me through the last three years of college!
@evanreidel22 Glad the videos help, thanks for the support!
I try to do this for the most part; point it out if I've missed one. Also, another thing I've started doing is just putting the other helpful video links in the video description.
Oh my lawd its EE the early years :) Amazing to see how far youve come!
I'm also planning on being a mechanical engineer (automotive emphasis) and let me tell you, these videos have made my love for cars grow even more! What I love about your videos are that they're so quiet, personal, and easy to comprehened. Keep it up, and whatever you do, don't add music/logos/overlays, unless your videos are being sponsored/advertised haha, because them you get paid!
Ole throwback Engineering Explained videos. It's amazing how much you grew and how comfortable you got behind the camera now. Your Genius articulation is on par with the engineering gods. 😀
😩
This is the first time I actually feel like I understand how a dual-clutch set-up works. I've heard it explained before, but never in such a way as to make sense. I really love your videos! Keep it going!
This is where the beauty of electronics kicks in: It knows the engine revs, if the car is accelerating or slowing down, your pressure on gas pedal and/or brakes, and using those parameters it pre-engage the best gear on the alternate shaft. If the car allows the driver to select the gear (not all DCT-equipped car do) then the driver could still "trick" the system: asking a shift down when the system prepared the gear up, then a slight delay would occur upon gear change.
You're welcome, good luck with the presentation!
If you are going to downshift, than you're likely braking, and at a lower RPM, so the computer would in most cases predict your next gear selection. You cannot skip gears, but you can select through them pretty quickly.
@J3n555 That is what happens, but the clutches alternate which is engaged. The clutches alternate and the torque transfers from one clutch to the other, and then through the transmission.
Glad it helped, you're welcome!
Dude! You're video rock!!! I am an math/science nerd, an engineer (in the computer security realm) and a gear head. You have a knack for really laying down the science in general terminology. Keep up the good work!
Sometimes they are used with paddle shifts, but many times these vehicles have traditional automatic gearboxes with electronic control of gear selection.
The gears are meshed but not all the gears are directly connected to the shaft. One of the shafts has the gears splined, so they rotate with the shaft. The other has the gears on bearings, so they rotate around the shaft at different speeds. This allows for the reverse gear to spin in an opposite direction while the other gears rotate in the same direction of travel as the rotating shaft.
one of the better explanations. ( of the actual working). Downsides can be found in other videos.
So young and chill. I swear, these days you almost lose it over torque curves. Good videos
i watch so many videos on dual clutch but i just dont understand how the stand by gear engage but not active, now i understand from your video thanks a lot , god bless, keep your good work
I agree to your statement. In my SST you can feel the clutches disengaging when you are about to stop. Interestingly when you are at a slight incline, roll back an inch or two like in a manual. On steeper inclines, the brakes remain engaged (once depressed) until they time out or you press the throttle.
Yes, since gear 1 is not connected to the engine until the switch is made, the shift is still smooth. Once it's made the engine will pop the revs up to match the lower gear's speed.
@keropoklekor007 I'm not positive what your asking. The collars move on a spline or notch so they rotate with the output shaft and can also translate along it. Sample scenario: When you're in 3rd gear and switch to 4th, the collar between 2 and 4 moves into 4th gear, and then the clutches switch which one is engages. Odd clutch disengages, even clutch engages. Hope this helps! Sorry for the language barrier.
damn this is good - now I understand. the power and the beauty of well-constructed diagrams can not be overstated
thanks a lot! do an entire series please, not just 1 video! i also want to know with all the stuff at the back, how does a mid engined car get 50:50 balance, which way does the flywheel face in them, is the engine redesigned to turn the other way around, how is the the transmission work if it's between the engine and the rear wheels while the driver is on the other side, also how does the side vents work and where are the radiators.. i have too many questions and the suspense is killing me! :D
Spectacular explanation, dude! Love how you can break it down so well! Anybody who knows anything about the basics or cars should understand!
Great video. It's kinda fun to see you when you were younger. Your production quality has improved a lot over the years. That being said... great video on how a dual clutch works. I had a different idea in my head on what it meant but now I understand and can really see the advantage to the design.
The non-engaged clutch is still spinning with the transmission, as it is ultimately connected to the wheels. It's not, however, connected to the engine, so the engine and clutch disc can spin at separate speeds.
Awesome...can you show the actual parts, the sleeves, the gear engagement, the electronics/programming, and what actually engages the right gear when the program runs. Thank you.
They will both be just as quick. The computer guesses based on your driving. If you're slowing down, you're more than likely going to downshift, if you're accelerating, you're more than likely going to upshift. It follows a series of rules like that in order to predict what your next shift will be. Of course, if it has it wrong, your shift will take slightly longer.
I'd love to see you remake this video with all your new fancy equipment. It's been a road, drive on EE!
There may be a short delay if the computer predicts it wrong, regardless it should still be a quick gear change. What it could also do is if you want to upshift and you choose to do so at 5,000 rpm, it would continue accelerating (or decelerating) in the current gear until the next gear had been chosen; that way you never lose power, and the gear shift is still quick.
Gear selectors, I touch on them in some other videos: auto vs manual and sequential gearbox.
Smart guy even with this simple explanation I’m still head scratching!
very unique explination man, considering it was a sinple drawing on a white board it was very very clear to understand, i had been wondering what a double clutch was and how it worked for a long time, thanks man just subscribed! :)
Very good explanation of Dual Clutch Transmission.
I see what you're saying - it's very brief and I don't expect the power loss to be anything significant.
So DST is 'just' a sequential gear box that engages two gears at the same time. Whereas the regular sequential can have the clutch always engaged, the DST alternates between two clutches when moving through gears. Very cool!
Down-shifting looks a bit weird though, looks like it would have to revert back to a form of single clutch sequential mode. But then again, you don't need or shouldn't instantaneous power when down-shifting.
For similar down-shift, you'd need three clutches!
@wyzapple So the clutch engaged will be switched automatically, the computer will judge the best time, OR, it can be done manually in cars that have paddle shifters - this is popular in more expensive cars but growing in cheaper cars as well. It gives you the ability to choose when to shift (the HUGE advantage of manual cars) but with a speed that's impossible to achieve in a manual car.
There has to be some overlap involved between one clutch releasing and another clutch engaging to eliminate any shift point flare-up. Awesome video.
Ahh, I get your question now. The collars can move independently of one another. They do not move together, as each has it's own individual gear selector which puts it in place.
Perhaps eventually, but basically it's just an automatic transmission with electronic control - nothing fancy. Same transmission as is in most cars, but with the capability of choosing your own gear, rather than letting the computer do it for you. These are also common with DCTs.
After hearing SO MUCH about dual clutch trannies, I now finally understand how they work. Great video (as all your videos are). And a huge attaboy to whoever invented this type of transmission.
great explanation. If you watch the sequential transmission video you understand this one as soon as you see the diagram
dude this is great, and even greater would be if you combine your knowledge and talent to explain these things with a 3D designer
Thanks! I was wondering the same thing, and your answer sounds so very obvious. Same thing goes for reverse. There has to be a pretty smart computer to handle that delicate balance of "feathering" the clutch on a grade vs how much throttle input the driver is asking for. Very interesting!
Thanks for the clear explanation. A DCT looks simpler than traditional automatic transmissions (with planetary gearsets and their own clutches), plus more efficient as there is no torque converter (I'm assuming latter). So why are DCTs being adopted just now?
Very well explained. You cleared most of my doubts.
Thanks!
This video is in my drivetrains course in college. Nice work!
It's a brief amount of time, and it's not the full torque that's being sent to both (the clutches can slip a little bit). Clutches don't simply burn up with a little slip, slip is required everytime you accelerate from a stop in manual cars.
Can you make a video about how mecatronic works and how activate clutchs?
Hello, I have a little sugestion, I was thinking that it would be cool if you could actually have the parts so that we could see what they look like. of course I understand this could cast a bit, what i currently do is watch your videos and then look at another video about the part where you can see what it looks like etc.
@baseballhn4 Pretty certain that the selector arms for all of the gears are computerized. The computer guesses (educated guess based on rpm, how hard your pressing the gas, etc..) which gear you will go into next (upshift or downshift) and before you change gears it's already in place and ready to go.
As for the torque time graph, probably so, but my intention was just to show that there is always some torque being delivered vs a conventional manual gearbox.
Your videos are completely perfect for what I wanted to learn today. Keep up the awesome work, man.
Car jerking - increased power from the lower gear. Car layouts (engine placement, etc.) has been requested. Eventually I'll get there, haha.
If the transmission is controlled just by the ECU, yes, you can skip gears, but if it's controlled by paddle shifters you have to go through each sequentially. A DCT will never use a stick shift, nor will it have a clutch pedal.
Nice job on the explanation! One thing im not 100% on is... on a dual clutch transmission there are two input shafts running into the transmission? I guess one inside of the other?
i have two questions:
1) how will i shift from 2nd to fourth gear directly?
2) how is the pressure plates actuated in the clutch housing?how does the pressure from one clutch is transferred to the other?
Hi, !st of all,thank you very much for the following: it was clear, clean,tight, interesting and professional! Would love to ask you on your next video (or even the current one included) to add some 3D sketches to your esteemed lecture.thanx man and keep the good work.peace:)
negru48, I think all of the dogs can independently slide in either direction along the output shaft. They don't all move as a group. If they did, lots of gears would be engaged at once!
You're welcome!
Good explanation! Have they been around long enough to know yet how reliable they are over time?
You're welcome, Torreto!
@Smigjo Mechanical. But 90% of what I show in these videos I've learned on my own. Mechanical engineering is basically learning the math to anything that moves and the dynamics involved.
Engineering Explained are there specific sites or books to read to learn by my own as you did ?
Awesome explanation!,,,,,,,Thankyou! It makes perfect sense to me now, why formula one and consumer- high performance vehicles have gone down this path. Your presentation skills are excellent, anyone could follow how a double clutch system works.....Good Job!
I'm watching this in 2015 thinking this is new tech... omg. Freaking awesome explanation!
This explanation is a hundred times better than my Lecturer, Thankyou :)
A question: Is there a specific reason why Reverse is connected to the green shaft?
Would it be better if it was connected to the even gears?
I thought about it and cant see why reverse and first would be connected to the same clutch (seeing as you would change from reverse to first pretty much always in sequence).
@remtheoneilo Uhh, the computer may be able to, if you leave it in automatic mode, but if you're in manual mode you have to scroll through them.
They simply will use a gear selector, typically these will be paddles around the steering wheel.
Dude thank you so much!!! I need to do a presentation about a DSG gearbox in two days and with seeing you explaining this I fully got it how I going to explain it in fromt of my class :) thanks bro!!!
Can you do a video explanation of the Wet Dual Clutch Transmission (as used by Geely/Volvo in their 7 speed DCT). I cannot find much details. Apparently more reliable but I cannot find much technical information on it. Thx. Keep up the good works.
This goes well for increasing gears shift from 1->2, 2->3. As explained when the Gear 1 is engaged, the selector rod get fitted in Gear 2 also. So Gear 1->2 happens in a fraction, smoothly. But what if the Gear is Dropped form 2->1 ? In that case will the transmission be smooth?
Some of them, yes. Others just use the typical automatic planetary set-up.
My first video to watch for you!!!
And really enjoyed it, u are really skilful in explaining, and making it easy to understand!!!!
Well Done!!!
Keep Up The Good Work!!!
Subscribed
Ahmed Al Atabi Thanks!
Yes, it will be an auto or semi-auto, where you can select the gears but you will not have a clutch pedal.
Very good video, i have a hard time learning new things but i feel like i got it 😀
Great video! I just bought a car with dual clutch. I love the way it accelerates!
Thanks for this explanation. I have a question about downshifting. Lets say that you are in 3rd gear, so it is the green shaft that is driving the wheels. You could engage 4th if upshifting, or 2nd if downshifting both from the red shaft. How does the transmission know which the driver is going to do? Also, will downshifts be just as quick as upshifts?
Great video, but ALL the input/output gears are meshed in a mechanically locked configuration. This is potentially confusing.
If you're foots hard on the gas, you're probably going to shift up. If you're on the brakes, you're probably going to shift down. And some algorithm for everything between to consider the rest.
Explanation is too good with proper content ..Nice video brother ...☺ Also make on more videos on mechanical engineering
what i dont undestand from the presentation is that the rotational direction of the output shaft it will be different from the one from the engine. How does it switch to the rotational direction of the shaft coming from the engine? Btw awesome videos, and sorry for my english:d
ive got a request! not sure where to go with it though :P how about a video with other gearbox options, like dog boxes, sequential gearboxes (rally and whatnot etc...) that would be crazy! hope you can make a vid of those!
I enjoy your videos. They are concise and provide a lot of information in a relatively simple way. You appear to be fairly young. What is your background? How have you gained so much knowledge at such a young age? Thanks
This may help answer your questions, as well as checking out the FAQ's. www.howdoesacarwork.com/p/about-me.html
I have watched several videos trying poorly to explain how a DCT worked. I got to 3:30 in this video and the penny dropped. I now understand the principle behind a DCT although I don't doubt that there are numerous engineering intricacies that I probably don't need to know. Thank you.
Great explanation. Can you skip gears on dual clutch tranmission?
Wow great video! even though it is 7 years old already...
Hey man, Nice videos, both these oldies and the new ones. I was wondering if you could do a video on how the MotoGP seamless shifting single clutch gearboxes work. Cheers
some said its still a 'secret' somehow..
Question: I know you have a video on sequential gearboxes, so what are the pros and cons between sequential gear boxes and dual clutches? Obviously, I know you must change the gears SEQUENTIALLY in a S-gear box. Which one changes gears faster? Why would F1 cars use a sequential gearbox over a dual clutch system?
You make it very easy to understand. Nice Job!
Thanks for watching!
You're awesome, man. Love your videos, keep up the good work. Are you majoring in Mechanical engineering?
I just saw you for the first time tonight 08282019 and it was great. The subject was dual clutch transmissions.I learned a lot instantly. I didn't see your website or email address. Please advise. I have a very important question about the fiesta so I need to ask you but I doubt this is the forum for that.
i have a quick question, i thought that the input and output shaft where on the same plain and lay shaft just bridged the power from the input to the output shaft. i might be wrong, im just trying to understand. Good job on your videos
Are those clutch plates (pressure plates) switched electronically w/ a sensor or such?? Is there friction plates as well?? (or is that the black ones that u drew?...ah, yes u explained that already, ok)
Sweet!! Thanks for posting...if I watch it (and your others) enough times it might get through my thick skull and soak into my brain.
If you downshift, you're likely going to be decelerating, and at low revs. You wouldn't likely rev up (and once you get to high RPMs, it's impossible) to downshift. The computer does what is most probable. That said, if you're sitting somewhere in the middle, and it chooses wrong (or not at all) there may be a minor delay.
cool video dude i been wondering how Dual Clutch Transmissions work thx
Thank you. Very good video. Simple and to the point. Keep up the good work.