Okay, now I'm thoroughly confused.
I thought dual clutch was strictly an automatic thing.
Oh no, not at all! Although automatic transmissions have varying numbers of internal clutch bands and packs to shift gears, that's a completely different thing from the clutch (or clutches) in a manual transmission.
With the manual transmission, the clutch connects or removes the flywheel from the input shaft, so the motor doesn't stall when you're stopped and to make it easier when you shuffle the gears around. This clutch is traditionally controlled by your left foot.
In an automatic transmission, the clutches apply pressure to one or more
planetary gear sets, causing them to rotate differently and change the gear ratio. These clutches are traditionally controlled by a valve body (essentially an analog computer) which is in turn controlled by the gear selector lever, or in the case of old Chrysler cars, buttons.
Oh, joy.
See above.
See above.
The torque converter in an automatic goes where the clutch would be on a manual transmission. Like the manual clutch, it keeps the motor from stalling when you're stopped, and aids in shifting gears. But it's not a clutch.
Now the really confusing part: Later model automatic transmissions have clutches where the clutch would be on a manual transmission, and it looks and even works like the clutch on a manual transmission.
But it's there for a completely different reason.
So your average automatic transmission is full of all sorts of clutches of varying shapes, sizes and functions!
That all makes perfectly good sense...but I'm still confused. I still thought/think that dual clutch is unique to automatic transmissions.
No. At least not the kind of clutch that is traditionally operated by your left foot. That kind of clutch is native to the manual transmission. They can take an automatic transmission complete with all those
internal clutches that make shifts feel like chewing rubber bands, and graft a double clutch onto the front of it. But it's still like chewing rubber bands! No thanks!
Like I said above, automatic transmissions,
by design use all sorts of clutches to do pretty much everything. The single clutch in a traditional manual transmission has only one function: to couple/decouple the engine's crankshaft (via the flywheel) to/from the transmission's input shaft. Poetry in motion. :driver:
As we already learned, manual transmissions use two or more parallel shafts to hold its gears, and the gears move up and down the shafts to enable different pairs of gears to mesh, thus giving you different gear ratios. No internal clutch packs or bands, no planetary gears.
Here's the tricky part. You have two shafts with gears on them, and one is the input shaft. Why is that one shaft the input shaft? Why not the other shaft? The answer is that you
can have more than one input shaft if you want to. That is, in a nutshell the whole basis for double clutch transmissions: You can apply engine power to either of the two shafts if you want to. You can apply power to more than two shafts, in fact. It's entirely possible that one day we'll see a 6 shaft, 6 clutch transmission with God-knows-how-many gear ratios on it.
The next logical question is "why?" I covered that in a previous post, but in essence it's for faster-than-human shifting and better efficiency.
Ugh! Not for me. *I* like making my own decisions. Therefore, as much as I would love to drive a race car, I would HATE having the sequential manual transmission it may very well have nowadays. Trust me, if I need to go from 5th to 2nd, there's a damn good reason for it! (Like traffic suddenly stopping on a freeway for an accident.) Or from 1st to 3rd. (Like coasting down a mountain.) I don't want any computer doing the thinking for me.
The good news is that you can tell the computer to get out of your way. And while flappy paddles may not lend themselves to the kind of gear-stirring that we both know and love, the transmission itself is
not a sequential gearbox. If you slow the computer down so it waits until you have the chance to do at least a
double-tap [sic], you can use multiple "taps" on the flappy paddles to go straight to the gear that you want. Inside the transmission it works exactly like it would with a stick shift, except that the computer is juggling what would be two sticks and the two clutches. But the important thing to know is that if you go from 5 to 2,
you actually go from 5 to 2, with
no stops in between. In fact, because of the second clutch you can go from 5 to 2 a lot faster than you ever could with a single clutch and a single stick shifter.
Granted, it's not as visceral as having your hand on the shifter, and feeling things like the slight eccentricity in the pilot bearing, the thrust from the rear end and other tactile feedback that you'll never get with flappy paddles. That's why quite a few people absolutely hate flappy paddles, and the major supercar makers offer a standard shifter on their cars.
No. Yes. No. Unequivocally no. Maybe. Yes. Okay!! Once every 10 years or so I'm in a situation where my clutch foot hurts like hell (creeping up to Griffith Observatory, in bumper to bumper traffic, to see the Space Shuttle Endeavour fly over the Hollywood sign comes to mind), and I find myself thinking--momentarily--gee, an automatic sure would be nice!
Told you so! :laugh: But you want it just for the moment, right? You're not going to give up that solid connection between the flywheel and the pinion shaft that only a manual transmission provides. No "slushbox" torque converter! And when you want it gone, it's gone. Poof! :hello2: Can I get an Amen?!?!?
Well, that's the beauty of the computer-shifted manual transmission. It gives you that direct connection, and the same random access gear changes that a manual transmission gives you. But it can do automatic once in 10 years, and go away the instant you want it gone.
The bad news is that you have to find something else to do with your left foot and shifting hand.
I thought these were different--I know they use paddles, but I thought they were sequential manual transmissions, meaning that you can only up- or downshift one gear at a time, in order, but it's still a manual transmission.
It's all about the interface. Flappy paddles are biased towards sequential shifting. A bad interface. But as long as the transmission itself has the same random access capabilities as every other manual transmission, love will find a way. :car: