Transformer Coil Winder

[cjenrick]

Hi! First time caller, long time listener.

I am building a coil winding machine for making small transformers.
I have a dc motor on a variac to spin the bobbin, and a 10:1 ballscrew to move the wire across the bobbin in order to lay down a nice smooth layer of wire.
The dc motor has an quad encoder on the tailshaft, and I want it to talk to a stepper motor that spins the ballscrew.

1) Am I in the right forum

2) I need to change the traverse rate of the screw in order to accomadate different wire gauges. What do I need to do this? A stepper driver, obviously, but I need some sort of user interface between the encoder and the stepper for setting the traverse rate. I am trying to keep it simple, as I am not an experinenced machinist, just a electronics tech. I do not need to have a zillion different traverse settings, maybe just a 8 position dip switch would be enough. I guess I need a device that says 8 pulse in equals 16 pulses out to the stepper, or 8 pulses in equals 24 steps.

Thanks for any ideas, suggestions, websites, etc!

cj

[BCwanderer]

A simple fast solution
You can use a microswitch turning to advance the second stepper guide.
The cicroswitch can give you step signals by Triggering it by adding bumps on your bobbin
Adjust the number of clicks to match the advance needed on the guide.
The guide can reverse motion by the use of a limit switch at each end of the guide's travel. This would set the direction of the second steppers motion.

Electrically, use a pic micro to set the ratio.
Use a variable resistor to adjust the rate setting by reading the variable resistor with the ADC in the pic.
The pic can drive both the steppers with step and direction signals.
Use your limit switches to reverse the direction of your guide's motion.
If you roll your own electronics
Stepper chips
http://www.allegromicro.com/sf/3984/
http://www.allegromicro.com/sf/3979/
http://www.njr.co.jp/pdf/ee/ee04005.pdf
http://www.njr.co.jp/e05/ee.htm
Driver projects
http://www.fromorbit.com/projects/picstep/index.php
http://www.datasheetcatalog.com/data...LMD18245.shtml
Or you can buy a CNC driver program like TurboCNC
http://www.dakeng.com/turbo.html
or Kcam
http://www.kellyware.com/kcam/index.htm
and write a computer routine to drive the steppers

[Ron22]

I use to work at a company that wound transforems. The hardest part is what to do at the end of the bobbin. To get a good lay of wire you need to change directions on the cairage very fast. This gets real hard the faster you spin the bobbin.

[cjenrick]

Thanks guys!

Cool links, think I will roll my own driver and save some Gecko money.

Ron, I was thinking about that issue. Probably going to use a simple manual switch to reverse direction of the stepper since this is a low production situation. Maybe flipping the rev sw before the wire gets to the end of the layer might help.

After I build a driver, the last hurdle is to figure out a way to divide the encoder counts to match up with my wire gauges. So I need a user interface that can say 5000 encoder pulses equals 10 half steps for 0.001 wire, or 5000 encoder pulses equals 100 steps, etc.

Thanks again! Wonderful forum here.

cj

[Al_The_Man]

You need an adaptation of this application
http://www.galilmc.com/support/motio...oaf_slicer.swf
Al.

[greybeard]

I'm sorry that I haven't been able to work out how to post a link to cross reference to another thread in the zone. However, I posted earlier today an idea for a coil winder on the thread
http://www.cnczone.com/forums/showthread.php?t=14973

I hope that works (the link!!) and I hope it might be of use.
I envision adjusting the mechanism to suit the wire thickness by simply adjusting the geometry of the guide arm/pivot dimensions, coupled with the choice of screw thread from the junk box.
John

[greybeard]

Yes, it worked. The later posted diagram is my current thinking.

[ynneb]

I have bought this up on the Mach forum.
I have suggested that if one of the wizard writers there could make a program to wind coils.
The things I feel that need to be taken into account are....
Wire guage
Spool thickness
Spool width
Etc.

Judging by the responce, I think it will be a short amount of time that such a wizard will be launched, thus enabling us to make our own winding machines easliy.

I have often considered macking a CNC winder too.

[contactirfu]

Why forget the Composite Industry, they is whole lot of requirement for cnc winding machines for making composite pipes and cylinders...

If Mach in the form of plugin is available then it is fantastic........

Thanks
Irfan

[ynneb]

See a video of the prototype been run by Mach 3 wizard http://machsupport.com/forum/index.p...sg7542#msg7542