capstan drive sizing problem
capstan drive sizing problem
(OP)
I want to creat a capstan drive on an engine dynomometer. The drive wheel is aluminum 2.5" dia X 1" wide, running at 12,000 RPM and the driven wheel is 7.5" dia X 1" wide with bonded buna tire shore D 70.
The wheels need to resist a 27# shear load at the area of contact.
The question is how much do I have to load these wheels together to do this?
TIA
Terry
The wheels need to resist a 27# shear load at the area of contact.
The question is how much do I have to load these wheels together to do this?
TIA
Terry





RE: capstan drive sizing problem
Don
Kansas City
RE: capstan drive sizing problem
I need a ballpark number so I can be sure the system bearings will handle the load.
RE: capstan drive sizing problem
It's the rpm that I would be more concerned about. You have to pick a bearing that can handle that speed (4000 rpm). That puts you in the realm of ball or needle bearings, which have load capacities many times what you're needing here.
Also, your two cylindrical surfaces had better not have very much runout or you might be bouncing around and/or tearing up the rubber. Good luck!
Don
Kansas City
RE: capstan drive sizing problem
Friction with worn rubber can be significantly lower than with clean, new rubber. To be conservative, I'd assume a friction coefficient of .3. You could increase friction considerably by knurling the aluminum wheel.
Your loads and speeds seem pretty high for a rubber wheel.
RE: capstan drive sizing problem
I've decided this isn't a very robust design, so I'm going to change it to a .08 pitch MXL belt drive on the 2.5" dia. pulley driving a smooth face 7.5" dia. wheel.
Terry
RE: capstan drive sizing problem
RE: capstan drive sizing problem
Terry
RE: capstan drive sizing problem