Den tirsdag den 15. december 2015 kl. 05.27.50 UTC+1 skrev John Larkin:
why mechanical?
Hybrid give you the "buck-boost" and just a small battery gives you the boost needed to get decent acceleration even with the wimpy engine that will be enough at a constant speed
-Lasse
He is being tongue in cheek. A planetary gear set *is* a buck-boost converter.
-- Rick
where do you find a continuously variable one?
-Lasse
Why does it need to be continuously variable?
-- Rick
Something like was (is?) used on snowmobiles?
George H.
a buck-boost is
-Lasse
On Tue, 15 Dec 2015 10:49:00 -0800 (PST), George Herold Gave us:
Been around a long time. Extra wide V-belt and variable cone drive spool.
Remember the little race cars they let folks drive around in the 80s on up? They had/have them too.
CVT is the holy grail of automotive design. There have been all sorts of attempts, mostly failures, and a few that work with small engines.
It's impressive that the basic car drive train - piston/crank gasoline engine, poppet valves, gears, differential, brakes - hasn't really changed much in a century.
The latest breakthrough in jet engine design is... gears!
I believe they used roughly the same battery technology in the original Insight, but I have a 2009 Honda Civic Hybrid. (My daughter has a 2007, too.)
a 2001 model the
Yes, the Insight seemed to do a lot better than the Civic. Quite possibly the much lighter weight helps.
My Civic hybrid has 120K miles on it, my daughter's has 150K+ now. Both have had the hybrid battery replaced. Mine was under warranty, but for that you get used cells tested and assembled into a pack. Hers was out of warranty, we ended up paying half the price, but she got all-new cells.
Maybe, aluminum will corrode badly with salt, too. Also, it fatigues under cyclic loads.
Jon
Well I hear they are making cars with more and more gears in the automatic transmission. (Looking at the pictures of transmissions reminds me of when I bought my '84 Datsun/nissian pick-up truck. I came with a busted transmission... sitting on the front seat when I towed it home.) Hmm more than 30 years old now, does that make it a "classic"?
George H.
The Honda Civic Hybrid has had a CVT ONLY since I think 1996 or so. Before that, a manual was an available option. So, they've sold quite a few CVTs, and had relatively few problems with them.
They have two cones and a metal chain that can be slid from one end to the other of the cones.
Jon
OK, they are catching up, then!
Jon
Something like this (for hybrid electric-pedal bicycles):
Two-input planetary starting about 9:00:
Infinitely variable tranny "D-Drive":
A patent:
Paul
I recall they use clutches to lock one of the three gearbox ports, and vary the load on the motor/generator electronically. That variation can be continuous...
The Subaru XV seems pretty successful.
Turbofan engines have always had gears between the turbine shaft and the fan.
On Wed, 16 Dec 2015 09:52:31 +1100, Clifford Heath Gave us:
The idiot probably thought that a turbofan front fan actually cranked at 100k+ rpm.
On Tuesday, December 15, 2015 at 1:34:45 PM UTC-8, Jon Elson wrote: ...
.... The Honda Civic was introduced in 2001 - it had a manual transmission option through 2005. So I think you slipped a decade.
Honda's first hybrid was the 2 seater Insight 1 from 2000 - 2006 it also had a choice of manual or CVT.
The variable pulley CVT system seems to be limited in its power capability and can get unreliable at > 100HP.
kevin
So? A car transmission doesn't need that, especially with an electric motor.
-- Rick
exactly with electric drive you can use a "buck-boost"
-Lasse
** Operating RPMs for aircraft props, drive fans and hot end turbine blades all follow the same simple rule - tip speeds can approach but not exceed the local speed of sound.
At 20C this is about 330m/S, at -50C ( ie high altitude) it falls to 290m/S.
At 3000C, ( ie combustion temp ) it rise to 1000m/S.
... Phil
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