Constant torque motor

I just quoted a job wherein I planned to use air motors to drive take-up reels on a tape dispenser. The take-up reels peel the backing off the tape and get it out of the way. Air motors have nearly constant torque at low speed down to locked rotor. We would set the inlet pressure just high enough to maintain constant torque.

The client likes the design but doesn't want air motors.

Bummer:(

What about using DC motors with current limiting power supplies? Will I fry the brushes if the rotor is stalled for a long time? I'm thinking of using big motors and driving them to maybe five percent of rated current.

Those Minarik DC drives would be perfect for this - overkill but dirt cheap. I just ordered two yesterday to fiddle with. They raised the price to $56.95.

Doug


[Non-text portions of this message have been removed]