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JML31347

CVT ( Constant Variable Transmission )

by JML31347 Aug 16, 2018
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You must understand that the shape of gears does not affect the ratio. Ratio is controlled by number of teeth , ie if the driven gear has 10 and the driver has 5 , then you would have a 2:1 ratio and vise versa.
In the case of cone shaped gears of the same shape and number of teeth , the ratio changes with the contact gear or sifter gear .
That is why in the illustration the center shaft called the shifting shaft which is spring resisted , when pressed will move the shifting gear to different positions by such changing the ratio of input to output shafts.
It is like a belt driven pulley system on a centrifugal clutch system , just that it is positive contact and drive .

No, this nothing like a belt driven system (CVT or Reeves drive), the belt changes speed due to the sheaves changing diameters, you can't change gear diameters without changing the number of teeth, I challenge anyone to make this and post a video of it not just spinning but actually changing speed from input to output!!

I challenge you to make one and prove me wrong !
And it is exactly like a Reeves drive !

I see how this will seem to work with no load, but relying on friction it will simply slip when loaded, and sir you make the mistake of calling the wheel in the center a gear, witch it is clearly not, but this thing might work OK if the "shifter gear" was a urethane skate wheel (if the material its made from can withstand some preload.

I guess you can see the serration on the cones ?
One might call them gear teeth , they serve the purpose to give the rubber ring something to grab hold.
And NO it is nor a skate wheel , a skate wheel is to hard . The O ring is of a composition that has a magnetic polymer as part if its makeup and its hardness can be changed by the application of a modulated mag field

I'm a little baffled as to how it would shift, considering the gears are tapered but the ratio never changes, the teeth just get wider and narrower.

You're looking at the center shaft as the output. It's not. In the drawing the left shaft is the output. The center shaft would be driven between the gears to adjust the ratio. Think of the center more as the gear shifter.

Yes I have tested the model and I will have a pic coming soon.
The movable shaft at this time is moved by the user... in a full working model there would be some sort of solenoid or hydraulic cylinder performing the movement.
Understand this is a concept model that can be expanded on.

I get it now. Thanks for the explanation!

Have you tested this? What forces the shaft gear to move down?