Need Help!- Toolchanger looses position

[mniadna]

I have a 1997 VF-O. The tool changer seems to intermittently loose position. It has happen to me twice already while I have been manually rotating the turret in MDI. It hasn't happen during a program yet. It doesn't error out until I try to re-orient the turret and smash the turret into the spindle, because it thinks it is going into an empty pocket(oops). I'm thinking it is a poor connection to the turret rotation motor.
Can anyone give me some insight before I start taking things apart?


Thanks,

[dcoupar]

I believe there's a switch with a roller that counts tool stations. It may be defective or out of adjustment. You should be able to watch the switch status change if you go to the diagnostics page and watch TC MRK. It should be 1 when the geneva gear in position and 0 when it's rotating. Also, TOOL #1 should be a 1 when Tool #1 is in the ATC position.

[Haas__man]

Exactly as DCoupar says - there is a rolller limit switch inside the turret casting that may well be faulty.
Remove front cover from toolchanger.
Inside you will see a motor that is bolted to a small subplate with two switches mounted to it.
Remove the whole assembly from the machine by unplugging the electrical connections and removing 4 cap head screws.
You will see two roller limit switches attatched to the sub plate - one counts each tool station - the other finds tool one.
One of these two switches is very likely to be faulty.

Hope this helps

[mniadna]

Thanks, I'll take a look. What is the proximity sensor for that sticks down into the turret? I can see it when the turret slides in and the door opens. There is one pin there that it reads. I assumed the pin was what it used to orient.

[Machineit]

If I am reading your initial post correctly, you are rotating the turret in MDI, but not actually doing a tool change. Are you using M39 to rotate the turret only or M06 for a tool change?

The tool slot next to the spindle should always be empty, so if it is not after you rotate the turret, that is operator error.

If you wish to go forward or reverse, just use MDI/FWD or MDI/REV. If you wish to go from tool 1 to tool 6, for example, use MDI mode and enter T6 M06. You can rotate the turret to a specific position by use T6 M39, but this should not be done unless you are trying to recover from a tool fault or something like that.

The key to this is that it does not happen during a program, but only after you have rotated the turret.

Hope I read and understood your post correctly.

Cheers---Mike

[mniadna]

Machineit,

It happend when I was touching the tools off. I use, and have always used "ATC FWD" or "ATC REV" to select tools(takes less key strokes). Type in the tool number, then hit either key. Twice already, it has come up a pocket short. Say I called up T17, It would grab T16 and tell me it had T17. Every toolchange from there on out it would grab the next lowest number tool, until I re-orient the turret.

[Haas__man]

On a '97 VF0 you should not have any proximity sensors anywhere. There are two roller limit switches that hang down into the carousel area(on the turret motor assembly). One counts motor revolutiions (tool pockets), the other hits a dowel peg to tell the machine where pocket one is.
As for why this does not alarm out in program its hard to say - but I'm almost certain your problem is with the switches. The two switches are exactly the same so i you wanted you could swap them to see if your fault changes.

Hope this helps