autogyro's Transmission Concept

[Jersey Tom]

You are also simply calculating the instantaneous torque output as 350 ft-ibs based on the torque capability and characteristics of a conventional layshaft, dog engagement, (so called but not in fact, seamless) gearbox. The position on the gear train to measure the instantaneous torque capability on the ESERU would be at the tires as their is no clutch and constantly variable torque positive shifts.
Thank you for further confirming the potential.
More please.

Hm? Shouldn't matter. Torque is torque, reductions are reductions. Ultimately, your mystery box is going to have to withstand peak input torque from the engine on one end, and peak output torque on the other. The engine isn't going to change its peak torque output based on what load you put on it.. standard gearbox or not.

Let's say the engine does deliver 350 ft-lbf peak.


If I remember right that's at least a 12 or 13:1 overall reduction from the crank at the lower speeds, or about 4500 ft-lbf of output torque.

In any event I'm still waiting to hear how much your magic box would cost to fabricate, on the mechanical side. Say for a single prototype.

Potential peak output torque, calculated from maximum input torque from the engine, using gear ratios, is never present, in a vehicle of set weight and a restricted tire size and grip capability.
One of the first real world things I learned about gearbox technology.

Still not really in agreement. I'm not talking about 1st gear launches.

By 3rd gear let's say, you're not going to be overpowering the tires in a straight line, but there's still quite a reduction. Might be 12-ish:1. Personally I figure an F1 engine would put down closer to 250-300 ft-lbf torque, which still puts you on the order of 3000+ ft-lbf of output.

In any event, the engine CAN deliver the full peak torque to the input of the gearbox and through the tires. The car isn't always traction limited.

[autogyro]

The other variable factor is aerodynamics, both downforce relative to speed and drag.
Perhaps Nick Worth has the answers but then perhaps not.

[autogyro]

You can measure the torque output for a complete vehicle, only with a dynomometer either fixed to the drive hubs or on a rolling road with built in slip (so inaccurate). Neither gives a result for true on road comparison.
I worked for some time in a company importing mobile dyno's and running static dynos on race engines, measuring all types of engine output. It was amazing just how divorced stated manufacturers figures for engines particularly bhp claims. were from the actual true output figures. I do not think we ever found one close.
When I first designed machines for both cutting welding and testing torque converters in the after market, I soon found the problems associated with testing without simulating the slip and variable reduction in torque on the output, and the consequences.
Blowing up torque converters was not a pleasant experience and neither was putting rods through crank cases at 10,000rpm using hub dynos that also do not simulate vehicle inertia and tire slip. A Ferrari 250LM engine rebuild is not cheap.
So can you give me the details of how you conclude your in service torque figures?

[xxChrisxx]

BHP figures are now typically measured by an engine dyno. It's a bit old school to call something measured on a rolling road BHP. It should technically be wheel horsepower.

That could be the discrepancy. Although rolling road dynos are BS, they depend on all sorts. You can get loads of different readings throughout the range just by increase tyre pressures.

[autogyro]

BHP figures are now typically measured by an engine dyno. It's a bit old school to call something measured on a rolling road BHP. It should technically be wheel horsepower.

It has nothing to do with wheels.
It depends entirely on how the horse power is measured. The 'brake' is in the dyno, whether a rolling road a 'bench' dyno or a hub dyno.
It is real world engineering not the emaciated computer maths that most modern 'engineers' think is what makes them engineers.
I have a lifeboat stationed near where I live and I visit often.
Let some of those posting on here should come and help the crews 'engineer' when they go out on a shout in a force 10. Teasing the best out of those two huge turbo diesels in a tiny little engine room going up and down 30 plus ft, will soon sort out the 'real' engineers from the wimps.
You will not have any problem with the effects of output torque after that.

[Jersey Tom]

So can you give me the details of how you conclude your in service torque figures?

We're talking ballpark numbers here.

The engine doesn't care what tires you have on, or what your drivetrain losses are when it's under load. Load is load is load, and in this case I'd be interested in characterizing the maximum torque going INTO the gearbox, NOT after the rest of the losses through tripod joints, tires, or whatever.

A F1 car is only traction limited some of the time. That means, at some point, the engine WILL be able to put all of its peak output torque into the receiving end of your mystery box.

As for peak output torque, that's open to a host of variables. At speed though, in 3rd gear, the car isn't going to be overpowering the tires in a straight line. They'll take all the torque you can throw at them.

So at a minimum the output side of your mystery box is going to have to withstand that input * the total reduction. Peak values with inertia and in lower gears will be higher.

If you figure a F1 engine to be on the order of 800hp at say 17,000 rpm, that's around 250 ft-lbf of torque. If the car requires a 12:1 total reduction in one of those low gears, that's ~3000 ft-lbf output torque from the gearbox. That sounds about right for a car accelerating in the 1.7G range.

So can your magic box withstand those torque levels on the input and output end?

[autogyro]

So can you give me the details of how you conclude your in service torque figures?

We're talking ballpark numbers here.

The engine doesn't care what tires you have on, or what your drivetrain losses are when it's under load. Load is load is load, and in this case I'd be interested in characterizing the maximum torque going INTO the gearbox, NOT after the rest of the losses through tripod joints, tires, or whatever.

A F1 car is only traction limited some of the time. That means, at some point, the engine WILL be able to put all of its peak output torque into the receiving end of your mystery box.

As for peak output torque, that's open to a host of variables. At speed though, in 3rd gear, the car isn't going to be overpowering the tires in a straight line. They'll take all the torque you can throw at them.

So at a minimum the output side of your mystery box is going to have to withstand that input * the total reduction. Peak values with inertia and in lower gears will be higher.

If you figure a F1 engine to be on the order of 800hp at say 17,000 rpm, that's around 250 ft-lbf of torque. If the car requires a 12:1 total reduction in one of those low gears, that's ~3000 ft-lbf output torque from the gearbox. That sounds about right for a car accelerating in the 1.7G range.

So can your magic box withstand those torque levels on the input and output end?

If any of the current gearboxes can then so can mine.

[F1_eng]

Ofcourse not. Or I would have thought and designed it already.

Is this still being discussed?

People should start thinking about tractive effort required which can only be applied through the tyres which came through the gearbox.
That should clear it all up to people if you think of the system in that way.
The torque in each drive shaft can be estimated from wheel tractive force, this torque must travel through from somewhere and remember that power is conserved, that's a good enough assumption for this case.

Autogyro, I think your comment about engineers and maths is crazy, normally this type of comment comes from a person envious they can't do the maths.

[flynfrog]

Im still pissed I have yet to drive a train.

[autogyro]

Oh dear, tractive effort and Math. Now we will never know.

[F1_eng]

Care to elaborate?

[autogyro]

Care to elaborate?

I cannot elaborate with Math, unless I reveal more of my geartrain.
You are also well aware of the limitations of trying to calculate the capabilities of gear systems, without test data.
A full feasibility study needs to be undertaken on my ESERU, which will need the construction of a specific and different test cell to any other gearbox test cell used up until now.
This requirement has been confirmed by two separate F1 companies but there is simply insufficient funding available. I am waiting for another avenue to open up.
If development was ongoing I doubt I would be posting on here.
You are correct F1-eng, there is little point in further discussion, the debate is degenerating into word semantics and philosophy and is of little technical use.

[xxChrisxx]

It depends entirely on how the horse power is measured. The 'brake' is in the dyno, whether a rolling road a 'bench' dyno or a hub dyno.
It is real world engineering not the emaciated computer maths that most modern 'engineers' think is what makes them engineers.
I have a lifeboat stationed near where I live and I visit often.
Let some of those posting on here should come and help the crews 'engineer' when they go out on a shout in a force 10. Teasing the best out of those two huge turbo diesels in a tiny little engine room going up and down 30 plus ft, will soon sort out the 'real' engineers from the wimps.
You will not have any problem with the effects of output torque after that.

You obviously fail at modern nomenclature.

It's doesn't depend on anything. Brake power is measured at the crankshaft. end of.

[Ciro Pabón]

Hey, hey, hey. Cool is better. Again: attack the post instead of the poster.

Time will tell, after all. The Internet is not going to disappear tomorrow, nor this forum.

If you're impatient, let's continue the "8 questions game". I'd tell autogyro is giving a lot of clues. With all due respect, I'd say his posts are craving for a little reverse engineering.

I'm devoted to structures, so, how do you have just one bearing? Is the other "end" supported by the load somehow or are the components narrow enough for the journal to take the loads? Frankly, I don't get it.

I repeat: only the structure, thanks. I frankly don't get half of the talk of F1_eng or riff_raff in this thread and they know it, thank heavens, that's why they explain things to me and the rest of the "gearbox impaired" world like they speak to their grandsons or nephews.

Out of thread, I repeat something I've sternly remembered many times in the forum, that perhaps other members have conveyed in a different manner: we don't trust authority in engineering. Anything can be explained, you don't need to argue in a technical discussion about your personal merits, or you risk falling into the ipse dixit problem. Rest assured: we find your posts pretty interesting in themselves.

After all, if you are beyond some of the worries of this world, you want new generations to learn to appreciate the merit of ideas by themselves, no matter who presents them and I really want this forum to instill that notion. Just check the threads by our own incomparable Feliks if you don't believe me: we sincerely welcome your kind of people.

Finally, I would like to ask what kind of problem autogyro is solving (the why, not the how). For example, do you have at hand a graphic (sorry, I'm pretty visual) that explains how efficiency varies and where is the "gap" your invention exploits? We have thousands of visitors each day and many need the true basics in our own specialty subjects (I'm one of them, btw).

[mike]

forces on an planetary gear sets? any1?
if F1 car uses plantary gear sets what size does it have to be to withstand the load, comparatively to a paired gear set?

lets not try to look to prove him wrong and try to find a way that it could work in a 110mm cube.

like what they do in mythbusters........