The wheel inside the wheel: the virtual rubber circle

Ask a question or request a feature related to the website or forum...

Moderator: scott

Post Reply
User avatar
path_finder
Addict
Addict
Posts: 2372
Joined: Wed Dec 10, 2008 9:32 am
Location: Paris (France)

The wheel inside the wheel: the virtual rubber circle

Post by path_finder »

Sometime we need to let roll a small wheel on the inner rim of another cylinder.
A trivial solution consists of using some gears.
But in almost cases a simple contact should be sufficient, but two metallic surfaces in contact give always a skid.
There is a very efficient way to make the job by using two rubber ring bands (like those for fixing the camping tents)
The animation below shows the assembly.

The small travelling wheel (linked with the center) is in green and must absolutely roll on the black circle with an excellent contact.
So far you shall install a certain number of nails at the external side of the circle (pins in black)
Then install the rubber rings around these nails.
Don't forget to provide another set of nails, alternating their positions with the previous set, and to install a second rubber band.
There will be always a contact with the rubber because the overlapping of the both rubber bands in front of each nail.
You have just to adjust the tension of the band for limiting the friction.
Have a good ride!
Attachments
virtual_rubber_circle.gif
I cannot imagine why nobody though on this before, including myself? It is so simple!...
Post Reply