Re: [CAD_CAM_EDM_DRO] Auto tool changers

Hi Bill,

Perhaps if a simple encoder disk is added to the turret. 6 slots (one
to the edge), would allow two photo interrupter sw's to report the
position of the turret. A PIC could then drive a stepper (even a simple
unipolar driver), and do the "rotate past, drop back to lock" sequence
that you've said is required to change the tools. I have a Sears/EMCO
5" lathe (no CNC... yet), would this fit on my lathe? How much? I'd be
interested in a swap of some kind to get a mechanism to work with (kinda
putting the cart before the CNC horse!).

It only looks like three tool positions in the pix?

Alan KM6VV


wanliker@... wrote:

>
> In a message dated 2/21/2002 11:09:26 PM Mountain Standard Time,
> johnhe-uk@... writes:
>
> > I'm thinking of three of four
> > tools. I've looked but not found any prices on the internet
>
> If you go to the following URL, there are pictures of the guts of an EMCO
> COMPACT 5 CNC/PC TURRET.
>
> http://www.grifftek.com/c5cnc/c5cnc.html
>
> This unit handles 6 tools, three lathe, and three boring bars, drills or ?,
> in a 5/8 bore mount with set screw, they alternate. It has a gear box, and a
> small DC motor, that is driven past the next tool position, takes a few
> seconds. Then is driven at a reduced voltage in reverse until the ratchet
> stop engages, the motor stalls, and keeps attempting to drive the turret into
> the stop. The motion in the original is controlled by timing, and reducing
> the voltage.
> It could easily be built, and equipped with a stepper if someone knew how to
> do the programing for it. There is no sensor to tell what position it is in,
> so the operator/programmer must input the number of steps, and the program
> just repeats one advance movement after another, then reverses to lock up on
> the ratchet stop.
> bill