Re: Automatic tool changing ?

[JohnDRoc-at-aol.com]

The Milltronics tool changer is not the best design - it has some inherent 
flaws (undersized gearing, if you aren't careful on manual change, tools fall 
out, etc.).  There is an arm that pulls the tool out and inserts it into the 
spindle, and I don't think it has the capability of random tool location.  It 
does have a servo/motor on the tool changer axis.  I've never actually seen 
it work, the control was dead when we got it.  The shop that owns it is 
planning on using it for a dedicated production job, so I don't plan to mess 
with the changer right away.  I'll probably have to come up with a manual rig 
for the drawbar.  Being a Mech-E, I'm not the worlds greatest coder to begin 
with, and when it comes to Linux I'm totally lost. However, I don't think you 
would want to control a tool changer with the same STG card that runs the 
Axes.  There is no need for continuous real time control of the changer, 
since the machine will be in "Pause" during the tool change.  The way the 
Milltronics changer appears to work is through a 4 (or 5 for 20 tool) bit 
wide signal from the main controller board into the Acroloop board.  The 
beauty of this is that the Acroloop board can be standalone and it has built 
in two-axis control capability, in addition to 24 DIO's.  So maybe up it to a 
6 bit wide signal, from the PPT to accommodate the misc IO functions, and 
that would leave 18 outputs to handle Spindle CW/CCW, Lube, Flood, etc.  
Don't know, for sure, though.  I'm still learning!

-John