Friction Drive Formula For Two Rollers In Contact
Friction Drive Formula For Two Rollers In Contact
(OP)
I am currently designing a drive system that involves two rubber rollers to come into to contact with each other. One roller is directly connected to my drive system while the other roller is free turning. I need to transmit the torque from the drive roller to the driven roller.
I would like to know the formula that will allow me to calculate the downward force and the roller width I would need to transmit the required torque to the driven (output shaft) based on the type of rubber and coefficient of friction?
Any response will be greatly appreciated!
I would like to know the formula that will allow me to calculate the downward force and the roller width I would need to transmit the required torque to the driven (output shaft) based on the type of rubber and coefficient of friction?
Any response will be greatly appreciated!





RE: Friction Drive Formula For Two Rollers In Contact
Take a look in Machinery's Handbook under `Friction Wheels for Power Transmission`.
I think your biggest difficulty will be in estimating your coefficient of friction between your rubber drive roller and whatever material you make your driven roller. Again Machinery's gives some information on this. But, for instance it gives the coefficient of friction between `solids and rubber` as anything between 1.0 & 4.0.
Regards,
Neilmo
RE: Friction Drive Formula For Two Rollers In Contact
Whatever you start with will have to
change as the rubber will harden and change.
What diameter rollers are you using? I would
not rely on friction alone but want some
compression between the two
curved surface to increase the contact area.
Best guess on my part. What durometer rubber
are you using ie how hard, what kind of atmosphere
will it be operating in?
RE: Friction Drive Formula For Two Rollers In Contact
RE: Friction Drive Formula For Two Rollers In Contact
Assuming no slippage between rolling surfaces and knowing downward force from driver as P, tangential force (F) between rollers is estimated as the coefficient of friction times downward force (F= u X P ). So far width is not tanken into consideration.
You have not stated what the driven roller is used for, so it is not possible at this point for me to present a formula with width as one of the variables.
But if bearing friction of the driven roller is the only variable then the torque from F must be greater than torque from friction.
During start up you must also consider the inertia (I x alpha) to be additive to torque from friction of the driven roller.
Good Luck!!