CVT v Conventional Gearboxes

[pgj]

With KERS being used next season, there is a lot of information coming out about CVT devices being used as a method for delivering power into the drive-train for flywheel KERS. It seems that there is so much more information, or misinformation, about now than there has ever been about CVT/IVT gearboxes.

With F1 seemingly wanting to reduce costs, does anyone have any information regarding the resilience of CVT gearboxes against seamless shift boxes? Is it likely that a CVT gearbox would be able to last for more than the present four races? Is a CVT gearbox subject to greater or less degrees of wear?

[WhiteBlue]

You are probably aware of the regulation that prohibits CVTs in F1. Traditionally there was also the problem of very lowe torque tolerable by CVTs. Now with the Torotrack system that can be overcome I guess. But still one would have to check efficiencies vs a shift gearbox. longevity is probably a matter of weight. How the two systems compare in that regard I don't know. I assume that the shift box is lighter at the same MTBF.

[pgj]

I see that Max is talking of a standard F1 gearbox and Xtrac has been mentioned in connection with supplying it. Perhaps there will be a rule change after all. It is a technology that has a lot to offer IMO.

[Krispy]

Why would Max want to homologate the gearboxes? I really like watching teams develop new technologies to gain an edge. The more design freedom you remove from the sport the less fun you have being involved in or watching it. I don't want F1 to become another NASCAR.

On the original topic: I assume you could get similar reliability out of CVT and standard transmissions. However, I think there would be greater inertial losses in the CVT transmissions inherent to there design.

[IanL]

We're currently prototyping a novel gearbox that can utilise CVT (without belts, cones etc) and provides complete, perfect seamless transfer of ratios - unlike the current 'seamless' system that has to 'blip' the engine throttle to adjust shaft speeds to cater for the ration change. In fact, our system provides Discrete Ratio, CVT or a combination of both if desired.

Our problem has been trying to find out exactly 'WHY' CVT is banned. We hope to receive feedback from F1 on the subject as there seems to be no reason other than possibly mechanical integrity - which does not plague our technology in the slightest.

http://www.eurekamagazine.co.uk/article ... able-.aspx

As for planned regulation changes and 'standardisation', it seems that F1 is trying to to outflank the Arabs. Personally, I agree with other responses that F1 is so popular precisely because of the innovation and creativity. Otherwise, why doesn't F1 simply make all the cars themselves and hand them to drivers on the day?.... Oh, that's already been thought of.

[rjsa]

We're currently prototyping a novel gearbox that can utilise CVT (without belts, cones etc) and provides complete, perfect seamless transfer of ratios - unlike the current 'seamless' system that has to 'blip' the engine throttle to adjust shaft speeds to cater for the ration change. In fact, our system provides Discrete Ratio, CVT or a combination of both if desired.

Our problem has been trying to find out exactly 'WHY' CVT is banned. We hope to receive feedback from F1 on the subject as there seems to be no reason other than possibly mechanical integrity - which does not plague our technology in the slightest.

http://www.eurekamagazine.co.uk/article ... able-.aspx

As for planned regulation changes and 'standardisation', it seems that F1 is trying to to outflank the Arabs. Personally, I agree with other responses that F1 is so popular precisely because of the innovation and creativity. Otherwise, why doesn't F1 simply make all the cars themselves and hand them to drivers on the day?.... Oh, that's already been thought of.

My understanding is that CVT with many other technologies are written off the rule book to keep development costs under control these days.

And might be taken into account that it sounded awfully when tested.

link: http://www.youtube.com/watch?v=x3UpBKXMRto

[D'Leh]

With KERS being used next season, there is a lot of information coming out about CVT devices being used as a method for delivering power into the drive-train for flywheel KERS.

I believe any flywheel solution that is going to be used will only use the flywheel as an energy storage. The connection will be be made through a generator. The energy is transfered electrically between the flywheel storage and the generator.

I also heard FIA doesn't want a purely mechanical solution. It would be a pita to correctly measure the energy usage of the system which is obviously needed because of the restrictions.

[mx_tifoso]

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[mx_tifoso]

....

But we should reamber that the AMT today was develoved in F1 more than 10 years, if CVT also have this chance, it may be different.

[xpensive]

Actually, there was an F1 car built and tested with a stee-belt CVT.
Never raced though.

http://8w.forix.com/altpower/williamscvt.jpg

[Scania]

Actually, there was an F1 car built and tested with a stee-belt CVT.
Never raced though.

http://8w.forix.com/altpower/williamscvt.jpg

Because FIA said "no AT"

If FIA don't do that, maybe 70% onroad cars will use CVT today.....

[mx_tifoso]

If FIA don't do that, maybe 70% onroad cars will use CVT today.....

....

[xpensive]

The question remains to me, how would the pros and cons with a Steel-link belt CVT stack up vs today's seamless-shift gearboxes on an F1 car? Would the ability to always run on the engine's optimum power output compensate for a lesser efficiency-ratio?

While being at it, can somebody please give a technical explanation on what makes a "seamless-shift" gearbox? riff-raff

[riff_raff]

xpensive,

A gear transmission (with discrete gear ratios) cannot achieve a true "seamless shift", so the term is a bit of a misnomer. However, what they can achieve is a very, very short shift event with virtually no loss of power to the wheels. This can be done with clever synchronizing drive dog mechanisms like the Zeroshift ( http://www.zeroshift.com/animation.html ), or through the use of dual clutch configurations.

[xpensive]

Thanks riff_raff, what an ingenious design, for how long has this been around, any patents etc?
So now we have ten F1 teams each individually developing contraptions like this, but I understand that Toyota took the sensible route to utilize the Williams know-how.