Mazak QT20 Tool changer

Starting this thread to help create a logic component for a Mazak ATC.

The turret uses a Geneva-mechanism with a AC motor .For position feedback it uses three proximity sensors that pick up on a encoder wheel .
The position feedbacks are as follows .
Pos 1: 0 1 0
Pos 2: 1 1 0
Pos 3: 1 0 0
Pos 4: 1 0 1
Pos 5: 1 1 1
Pos 6: 0 1 1
Pos 7: 0 0 1
Pos 8: 0 0 0

Outputs to the turret are as follows :
1. Turret unclamp 1: Moves the turret from clamp to unclamp when active and vice versa.
2. Turret unclamp 2:Doesn't do anything by itself ,but when this is not active turret unclamp 1 does not work .(Sort of a safety ?)
3. Turret rotate forward 
4. Turret rotate reverse

Inputs to the turret are as follows :
1.Tool position 1
2.Tool position 2
3.Tool position 3
4.Turret clamped position 
5.Turret unclamped position
6.Index sensor
7.Turret pressure down (Goes high when turret unclamp 2 is active)

I will post my pin assignments as soon as I get back to my workshop .


On the attached image the subscripts are as follows:
1. Turret Clamp and Unclamp position sensors
2. Turret position sensors 1 - 3
3. Index sensor




 

Another photo of the tool changer it self.

does the index go true every revolution of the motor???? if so, is it at the end of the turret movement cycle ??

or what I'm trying to ascertain is, how does the index correlate to the position switches. 

and this doesn't look to terribly complicated to modify my existing tool changer program for  the mazak. the big problem i see  is the lack of sufficient position decoding switches  to do error checking of the turret sensors.

a 4th wheel at the end shaft that is on in position in 1 and off in position 2 3 4 5 6 7  8 would allow me to put in a error checking routine to verify the switches work properly. 

I'll put together a rough draft with modifications tonight. 

 

I am not 100% sure what the index sensor picks up on .Looking at that first photo you will see anther slotted wheel that the encoder wheel is connected to ,this wheel has 8 pick-up slots in it .The sensor seems to go true at the end of each cycle .I will confirm this on Monday when I'm back at work .

i need to know how that index sensor works, I'm leaning towards it actuating lock 2 on the turret to prevent roll back etc between engagement

The index sensor goes true when a tool is in position ,and goes false in between every tool change .

ok, so it's a strobe, and how big is the slot ? can you post some upclose pics for me ? this just got easier, sound like I just need to add a output for the 2nd turret lock and change a few variable names for inputs and remove the diagnostic checks for the tool position input validity. piece of cake.

you will have to fix you directory and machine name but here is the build log, I tested it as far as I couyld with my machine simulation.A few things to note, you can adjust the motor on of time in the hal file, ideally you want the motor to run long enough to go 1 full revolution index on to index on, this might take some trial and error. if this doesn't work for you, lmk I can rework the motor control strategy a bit.



the motor off time must be set to a value GREATER than the POS input DEBOUNCE time, of the switches will never be read, I set both to .500 seconds by default.the unclamp comes on before the motor, when the motor runs it will cycle the turret lock off and on.



cinturn@cinturn:~/linuxcnc$ sudo halcompile --compile --install  MazakQT15.compCompiling realtime MazakQT15.cLinking MazakQT15.socp MazakQT15.so /usr/lib/linuxcnc/modules/cinturn@cinturn:~/linuxcnc$


obviously change the name of you machine etc in the command line but it does build and in simulation looks to work properly.

ALSO I added the ability to run 4 gang tools per pocket, so you can have a OD and a ID row of tools and up to 4 tools per pocket.

lmk how this works for ya a few deficiencys, currently the program does not attempt tp go fwd or rev to nearest pocket, I will add that in once we get control of the turret reliably. check for bugs, watch carefully. .


I am also including my post processor.put the turret in a safe position. goto MDI mode, enter G28.1. this will store the machine coordinates in absolute values not relative.  then use my post processor for fusion360 " if you use fusion360 " and at every toolchange it will call a g28ALSO very important, in your INI file got to the line for the setup codes and change the machine from radius to diameter mode.


 [RS274NGC]

RS274NGC_STARTUP_CODE = G17 G21 G40 G43H0 G54 G64P0.5 G80 G90 G94 G97 M5 M9

this should get you up and running, I think 

attached comp file.  updated file, removed  a motor function check that blocks reading tool changer position. 

attached file