Need Help!- Mazak alarm

[Bala]

Guys I am in a jam. Mazak super quick turn 200M, Mazatrol640 T
giving me an alarm"milling gear shaft sensor malfunction" every time I tried to index the turret.

[debco99]

Here is what I would do and I see this problem a lot.
Take the rear cover off the turret and what should happen is :

When you index the turret you will see the motor turn until it see the marker pulse (encoder) and then the gear will shift to the turret side, if this happens you need to check the prox switches which you will be able to see on the gear. This signal indicates the shift from milling to the turret side is satisfied.

They have led's on them so are easy to see if they work.

In the electrial print you will see the address's of the switch and can see if they are working on the control as well

If the gear teeth mis-align and prevents the large gear from engaging you will see a nut on the end of the milling drive shaft.

Loosen the nut all the way so the shaft turns free and push the turret index button, the motor will turn but only the motor, then tighten the nut back up and it should index properly.

Make sure it is free or when you index it will make a partial index then you have to get it back into position easy enuff to do....when you get the back off it will be clear

If you have the type of nut that has like 5 small set screws around the perimeter tighten them even.

I was kinda of in a hurry when I wrote this but feel free to contact me if you need any help.

Good Luck

[m@chinist]

Hi Debco99.

I made this three times already. Each time machine works nice for two - three days and then comes the same problem again.

The big gear is a bit loose - i may do a little movement in radial direction - about 0,5 till 1mm.
The spindle motor does not hold its position tight - i can move it a bit also.

What is responsible for "find a correct position" in this situation ??
Or Maybe You have some more ideas how to solve it ?
Any support could help us to solve the problem. Thanks.

[JCVineyard]

We had a problem like this on our QT250. It started after the night crew crashed the machine. The main turret needed to be realigned. along with the milling motor. What we found out was after using the live tooling. The shaft in the milling motor itself was not disengaging from the live tool. If we stoped the machine and turned the tool by hand just it would free itself and we could continue on untill the Technition was able to make the proper repairs.
this might help ?

[m@chinist]

we can do turret roration tool by tool with no problem
we can engage / disengage live tooling with no problem
we can also do it on by on: turret rotation, live tool on, off, turret rotation - and so on for two hours. works nice during testing. gears are engaging quite nice.
problem happens after two - three working days. 3 shifts per day it gives You bout 40 till 60 working hours.