by "Cé hé sin" (michael-m-mouse)
Published 01/20/2017 at 16:17
by "Cé hé sin" (michael-m-mouse)
Published 01/20/2017 at 16:17
Tags: Voith
; Diwa
STARS: 2
By way of distraction from Trumpphilia/Trumpphobia (delete as desired) I’ve been learning about this and how it works.
It’s a four speed automatic box with a counter rotating torque converter in the middle.
As so:
"SidewaysOnDirt still misses Bowie" (sidewaysondirt)
01/20/2017 at 16:20, STARS: 1
Why bother? If you want to learn about despair, there are certainly better ways.
"bhtooefr" (bhtooefr)
01/20/2017 at 16:31, STARS: 0
I’m getting the impression from your posts that Voith’s gearbox design process begins with some Anlage I controlled substances.
"RamblinRover Luxury-Yacht" (ramblininexile)
01/20/2017 at 16:34, STARS: 2
I note that the front planetaries at least are Simpson style and not Ravigneaux.
Why yes, I *have* been reading a transmission operations guide and related articles on Wikipedia recently...
"Cé hé sin" (michael-m-mouse)
01/20/2017 at 16:37, STARS: 0
Maybe so, but there’s method behind it all.
They’re designed to meet specific needs (smoothness and durability in the case of the rail ones) and they do that very well. The rail ones are so far as I know the only make you can buy, all others having fallen by the wayside.
"Urambo Tauro" (urambotauro)
01/20/2017 at 16:42, STARS: 1
I can barely wrap my mind around a 4-speed auto as it is. I couldn’t begin to guess why putting the torque converter in the middle is a good idea.
"RamblinRover Luxury-Yacht" (ramblininexile)
01/20/2017 at 16:54, STARS: 0
I think it’s because the typical coupling arrangement in the second pic has an actual clutch, and that clutch and the pre-gearing of the first set of Simpson planetaries allows setting an “engine speed” for the second stage without actually changing up the speed of the engine. It’s almost like a sequential manual with clutch driving a standard auto in series - allowing a very smooth start and a wide range of steady state operating speeds at torque stall.
"Cé hé sin" (michael-m-mouse)
01/20/2017 at 16:57, STARS: 0
There’s method in that too. The two epicyclics to the left (input) side of the converter do 2nd, 3rd and 4th which don’t involve the converter at all and whose output bypasses it (by going straight through) while the two epicyclics downstream of the converter are driven by it and provide 1st and reverse.
"Cé hé sin" (michael-m-mouse)
01/20/2017 at 17:57, STARS: 0
It’s a bit different to that in so far as there isn’t a stop/start clutch. What looks like one is probably a vibration damper or similiar The first epicyclic has an input from the engine and two outputs - one to the wheels mechanically (the blue shaft going right the way across) and one to the wheels via the converter. As speed increases more torque is transmitted mechanically. To create second gear the converter is locked (as in not turning, the impeller is immobilised) and then everything has to reach the wheels entirely mechanically. The two front epicyclics give 2nd, 3rd and 4th.
Reverse is provided by the right hand epicyclics, downstream of the converter.
By way of added interest, because the impeller is locked in the higher gears you can use the converter as a retarder. By applying a clutch the wheels drive the turbine which then just stirs up fluid and absorbs power.
"Rusty Vandura - www.tinyurl.com/keepoppo" (rustyvandura)
01/20/2017 at 18:20, STARS: 0
I watched a show recently about the 1000-hp Bugatti, the Ceyron, or whatever, with the 14-inch rear tires at $6,000 apiece, and all of that.
But I guess the transmission in that car is really something else.
"CaptDale - is secretly British" (captdale)
01/20/2017 at 18:38, STARS: 0
Automatic transmissions are already black magic and now Voith goes and tries to make me feel stupid with the explanation of how their Differential-Wandler (Converter) or DIWA works.... Thanks guys