On Jun 15, 4:27*pm, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:
I've got a machine that must keep constant tension on a stretchy roving.

I've got a slip-clutch on the takeup spool right now, but when it slips
(sliding friction being less that starting friction) it "unwinds" some of
the tension in the roving before it stops slipping... so it doesn't keep
the material in the right state for one of the intermediate operations.

Are there any over-torque protection clutches that maintain a constant
torque from their break-free settings? *I'd really rather see this thing
slipping constantly than starting and stopping.

LLoyd

Ideally, aren't there constant-torque AC motors that can be stalled
indefinitely?

So far your method is coming out a lot cheaper, I'm sure.

Dave