Re: [CAD_CAM_EDM_DRO] Constant torque motor

Hello Doug I have got to know one application of a wood lathe
where a threefase motor of 5 HP is run by an inverter.
It is tuned like a dc motor and can even be braked by hand.
As I understand that thing did never have any trouble in 12 years now
of any kind.
Air motors generally are van type motors, as soon as the motor stops
the vans fall down and frequently the air blows through and You lost your torque
until the motor can speed up again.
Good luck
Sven Peter

Doug Harrison wrote:

> 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
>
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