Tool Changer on a Partner I

[bwilkinson]

I am helping out a friend who has a Partner I with a six location swing arm type tool changer. For a number of years, it hasn't worked. We finally worked out (working with Milltronics) all of the prox issues, wiring issues, and software issues so that now it actually does what it's supposed to.

However, we have an issue that I don't understand. When the tool changer arm moves in, it does not seem to move in with enough force to snap the collet into the rotary table, so when the spindle releases the tool, the tool falls out of the rotary table. Then, when the swing arm retracts, it moves so quickly and stops so harshly that the tool on the opposite side falls out.

I checked for flow controls at the pneumatic cylinder, and found nothing. I wasn't able to take the time yet to find the manifold and check for a flow control there, as it is hidden behind the swing arm (put in the single most difficult place they could find!).

My questions:
(1) Is there a flow control for the air on this cylinder?
(2) Should there be a bumper on the cylinder rod to act as a stop when it retracts? There currently is not one.
(3) Any suggestions I'm not thinking of?

[ZZZZ]

Look for several small needle valves that adjust the amount of air used for the toolchanger. They may be located inside the housing behing the swing-arm, you may have to increase the flow to the arm-in side of the big air cylinder.

Check the Z axis toolchange height -
Go to MDI and give it a G32 to get to TC height.
Take the air off the machine, rotate the spindle, and push the arm in.
Go to HDW (if necessary) to adjust Z to get the buttons to just touch both sides of the vee groove on the toolholder.
Re-set the Axis parameter Tool Change Height accordingly.
This will also let you make sure that the clevis on the piston rod is correctly adjusted so you have enough travel.
Push the arm back out and re-connect the air.
Test by going to MDI - G32 sends Z to TC height, M19 orients the spindle, M23 sends the arm in, M24 takes the arm out

The cushions are inside the air cylinder on each end of the piston. They don't work when they dry out so make sure the tool changer is lubricated with air tool oil from the oiler. I have had to squirt oil into the the air lines to get enough oil into the cylinder before the cushions started to work.

If you are getting a big 'bounce', there is a small bleed-off adjuster screw on each end of the air cylinder you might have to tweak.

Good Luck.

[bwilkinson]

Thanks!

[bwilkinson]

Well, overall the tool changer is working well, with the exception that it still slams back open - even after we popped the air lines off and oiled the cylinder. It works better for a little while, then goes back to slamming.

I have a feeling that the cushions inside the cylinder are shot. Is there a rebuild kit for these cylinders? Any idea what model cylinder it is? I noticed in other places it was using Humphrey cylinders (made here in Kalamazoo), is this also one?

I know I could simply tear apart the machine and look, but it's now running nearly all the time, so I would like to get the information put together to minimize the downtime on it.

[chipsinpan]

the air flow control valves for the arm cylinder are spliced into the air lines under the fibleglass arm covers .
They are very sensitive , so just turn them a little bit .
I had some trouble with my arm not extending out far enough , even with the adjustable yoke end screwed all the way out . So I made a few 1/8" shims to bolt under the solid mount where the cylinder attaches to the column.