Re: Hysteresis Brake

--- In CAD_CAM_EDM_DRO@yahoogroups.com, erich10983@... wrote:

>
> I've done this several times for low torque payouts for sapphire

fiber and wire wound resistor machines. The simplest and best approach
is to use a shaded pole motor with DC on the motor coil. A shaded pole
fan, rated at 120 VAC can be driven by a 0 to 24 VDC to give a very
smooth, completely controllable viscous drag to your payout spool.
This is very inexpensive and works about well as any of the commercial
systems I've seen.

>
> As an extra, I've mounted a pot with a swing arm to monitor the

diameter of the payout spool to control the torque as the diameter
decreases.

>

That sounds just great, thanks! I'll be putting the brake on a drum
that the wire will wrap around once to avoid diameter issues, its all
very low speed stuff.

Graham