Infinitely Variable Transmission 1

[maxaccel]

why doesnt any auto manufacturers use this IVT?

http://www.torvec.com/technology/infinitely-variable-transmission

http://www.autoblog.com/2006/08/07/torvec-targets-medium-duty-market-with-new-infinitely-variable-t/

 

[MikeHalloran]

It may have escaped your attention, but CVTs are in volume production right now, in not so small cars anymore.

They will inevitably find their way into trucks when they can fulfill their promise _and_ survive in truck duty. Nobody will commit based on a sample of a mere one technology demonstrator vehicle.

Your friends are _way_ behind.


Mike Halloran
Pembroke Pines, FL, USA

 

[GregLocock]

There are many possibilities. It looks as though it uses a pair of swash plate hydraulic motors, so noise and efficiency and weight and cost spring to mind as likely difficulties.

What problem does it actually solve that the current myriad alternatives do not? Comapring your efficiency against a conventional 4 speed auto with TC is a bit of a bad sign, I don't think they are even sold in first world countries any more. My rather boring diesel car has a six speed auto with a pair of dry clutches, I wonder how its efficiency compares with that?

Cheers

Greg Locock


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[hydroman247]

Google "Claas xerion cvt"

 

[pontiacjack]

I guess I've never seen ANY implementation of an INFINITELY variable transmission...

 

[tbuelna]

pontiacjack-

Technically you have a valid point. An IVT would have an infinite ratio range in both forward and reverse directions. Most of these devices are more correctly described as continuously variable over a defined range transmissions, or CVODRT's.

 

[LionelHutz]

Is this basically a planetary gear drive with 2 inputs, the engine and a hydraulic motor built so that varying the speed of the hydraulic pump will effectively change the engine to wheel gear ratio? I could see it working better then a belt for heavy duty applications but I bet there are downsides to the hydraulic system they are not disclosing.

Isn't something like that done in certain hybrids using the electric motor?

 

[GregLocock]

Yes, that's basically how the prius works - one of the electric motor-generators acts as an input to a differential, the other input is the engine. They add a second MG on the output shaft.

That solution was first proposed in the early 70s and they even built one car.

Cheers

Greg Locock


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[LionelHutz]

So, this is yet another something old is new again?

 

[GregLocock]

Lionel - almost everything worth doing mechanically on cars had been tried by about 1922! Usually by Armstrong.

Cheers

Greg Locock


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[LionelHutz]

Ya, I really shouldn't have questioned that. It's no surprize someone is trying something old again. Oh well, it's a break from all the opposing piston engines that are going to save the planet.

 

[GregLocock]

Sorry I should have said Lanchester, Armstrong was heavy engineering.

Cheers

Greg Locock


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