D-drive

[bravekozak]

D-drive infinitely variable geared transmission.

How come I never thought of that?
It's so simple, that any machine shop should be able to make one and have it tested in a Festiva. Imagine never having to change a clutch again. Think of the weight saving.

[jawbraeka]

this idea is great.. i hope this becomes a factory swappable option for us.. IE, another car company makes the transmission and it bolts up to all the B series engines.. here's to hoping.

[lessersivad]

May want to read this before getting to excited;

http://www.gizmag.com/d-drive-redux/15120/

[Hot_Wheels]

i still dont understand it. Just transfers power to either shaft depending on speed, direction?

[jawbraeka]

still good in theory.. i hope this man makes a million dollars.

[Flyin4stroke]

This is a good invention for a tractor or something that doesn't need to shift gears and needs a lot of torque.

By the time you get something onto the input shaft to be able to make the variable speed work and change gears it will be as big as a regular transmission.
It's a cool idea and neat idea but I believe it's only half way to ever seeing day light. This guy needs to invent something to make the gears change. Or at least allow someone to do so. Or you can still save the day and you both make millions.

[sketchman]

Edited. Sorry. Thinking too slow, been up all night.



EDIT: Sorry, misjudged that last ratio. It does modify the torque, but only lower. Final is another 3:1 instead of 1:3. So total would be 9:1 constant torque multiplication at multiple speeds. Hmm.

[sketchman]

I think I broke my brain. I don't know anymore. You can get ratios from assuming a certain number of teeth for the small gears and then figuring for the large ones by circumference = pi x diameter. Given that the small gears are 1/3 the size of the large ones, that part is easy. But then at the end there is a crank arm instead of a gear doing the transfer, so it's not as simple, I don't think. Either way the gear ratio is a lowering one, but fixed. Ahh, I need coffee.

Yes, definitely only modifying (on the fly) the speed ratio. Hmm. It seems if you stop the bottom shaft, you get 3:1 total. This is confusing.