cvt (variator)

An internal look of a variator, a part of a CVT (Continuous Variable Transmission). What you see here are both a side view and a frontal view of the ACTIVE variator.

This variator has round weights (6 green ones in this ex) which are a key element here.
As the variator house spins by the engine, the centrifugal forces push these weights outside, and on to the wall of the second half of the variator house which pushes the driving belt (black) outside - changing the final drive ratio.

As I said, This part of the variator shown here is THE ACTIVE one in the system.

There is another PASSIVE (or SLAVE) variator, (not shown in this presentation) that looks SIMILAR to what is shown here. If you look at it working, then you'll see that it opens as the front one closes.
This PASSIVE variator has no weights, but just a spring that pushes the plates one to another, with the belt moving between them. The ACTIVE variator is stronger then the spring force, allowing it to control the passive's variator opening - in and out.

The combination of two variators, one that closes while other is open, and vise versa, is what constantly changes the final drive ratios.

You can see a better quality flash presentation here:
http://www.motoetc.com/home/2010/03/variator-cvt-continuous-variable-transmis...

Check out my other videos that explain other car/scooter/motorcycle mechanical systems.

Category:

Autos & Vehicles

Tags:

• scooter
• motorcycle
• cars
• transmission
• automatic
• gear
• box
• cvt
• constant
• variable

[kennyvanweert]

Now I finally understand how this works, thank you very much.

[pgwlgtnnz]

this is the best example of how cvt works... thanks

[siruga]

it changed my life...hahahahaha

[sanydreik]

Nice video dude

[Torvikholm]

Finally I understood how the CVT workes!

[magna59]

Nice vid....keep up the good work.

[janakarx]

thank you very much

[Colt041]

@Firewraithe1

it's kinda like changing sprockets on your bike, for ex. if you're going up the hill you need more torqe, so your front sprocket needs to be small (less teeth-smaller diameter) and your back sprocket needs to have more teeth (bigger diameter) than front one (driven by the engine, etc).

but when you want more speed it's vice versa, so you change your gears. the difference is that CVT does that all the time (giving you better acceleration to top speed ratio). hope this helps!

[moyadapne]

@Firewraithe1 There are two of these tapered pulleys in line and separated. Squeezing up one pulley, with a non-expanding drive belt between, allows the other pulley to open up. Variations on this opening and closing allow infinite ratios between high and low. There are better youtubes vids that explain this. Cheers.

[Firewraithe1]

I understand how it works, but I don't understand what it improves by increasing the diameter of the rotation.

[zeedjej]

Finally I know how that thing can move sideways, thanks!

[46ace]

Smowmobiles have been using this for years...