🚀 go-pugleaf

I occurs to me that the follow can be simplified:

>For the brake on the supply side pinch roller set a magnetic 
>powder clutch would be ideal. Of course the brake will 
>control the tension of the wire in the coating area.

Use a torgue motor - connected to pull the wire backwards.  That will
give a very smooth reistance as the driving capstan pulls the wire
forwards.  The torque can easily be adjusted with a small Variac.

Del Stanton   sd20@earthiink.net

On Wed, 07 Oct 1998 17:17:09 GMT, sd20@earthlink.net (Del Stanton)
wrote:

>It seems then central point that the system shoiuld have a supply reel
>driven by a torque motor , one set of pinch rollers with a brake to
>control the tension in the wire before the coating area, a second
>set of pinch rollers driven by a variable speed motor to drive with
>wire and a take up reel, driven by a torque motor has never been
>clearly stated.
>
>I would use two reels, perhaps specially made, so that the full length
>of wire can be wound on a reel with a negligible change in the winding
>diameter.  Let's say keeping the change in winding diameter between 5
>and 10% of the core diameter.  If you have sufficient distance between
>the driven set of pinch rollers and the take-up reel the wire might
>level wind by itself.  It would be worth the time to make a quick test
>to see if thre wire will level wind itself without assistance.
>
>The torque motors could be the small Bodine Electric AC  Induction
>motors.  Their torque is easily controlled by a small Variac.  C & H
>Surplus in Pasadena California sells these motors and small Variac
>Autoformers at surplus prices.  For the brake on the supply side pinch
>roller set a magnetic powder clutch would be ideal. Of course the
>brake will control the tension of the wire in the coating area.  C & H
>may have some of these in the catalog, I do not have it at hand as I
>write this.  They also have DC motors with tachometer outputs that
>could be used for the driving pinch rollers.  Also there are a number
>of suppliers of small, precisely speed controlled DC motor drives.  I
>think you would want to have a system with either a "digital tach" or
>a dc voltage tachometer, I would shy away from those DC controllers
>that sense the motor speed by calculating it from the applied voltage
>and the current drawn by the motor for this application.
>
>For the pinch rollers I would use one steel roller and a hard rubber
>pinch roller working together.  I would connect both the brake and the
>drive motot to the steel roller side,  The reel motors will not need
>any control beyond setting their supply voltage to obtain the optinum
>winding and unwinding tension in the wire, since the reels will wind
>at a substantially constant radius.
>
>Del Stanton  sd20@earthlink.net