Re: [CAD_CAM_EDM_DRO] Indexer

On Friday 09 May 2003 15:54, Steven J. Owen wrote:
<snip>
> Right now I am designing a rifling machine for muzzle loaders, and I need
> to intermittently index a shaft 120 degrees of rotation.
>
> Does any one know of a simple method (meaning cheap and or home built) of
> using a stepper motor and some type of controller that will cause the motor
> to rotate 120 degrees and stop, every time a limit type switch is
> depressed? Or some other method?
>
> I also need to activate a solenoid every 3rd touch of a switch or other
> electronic activating method.
>
> Any help gratefully accepted! Thanks! Steve
>

One possible way would be to gear the stepper to the indexer such that 120
degrees takes an integer number of steps. Use a 555 IC as your clock source,
and gate the pulses out to your driver board with a down counter set to the
number of pulses for one cycle. Use whatever signal you wish to preload the
down counter to start a cycle. When the count is met the clock pulses would
be gated off. The gate could be the enable input on the driver if one exists.
You should be able to find some ideas for dirver circuits in the files
section of this group. You could use three counter off the limit switch
(with debouncing) to trip the solenoid.

Of course it could also be done with a microprocessor or PC, but that might
get complicated depending on your electronic and programming interests.

Hope this generate some ideas.
--
Keith Bowers - Thomasville, NC