Automatic Tool Changer proof of Concept

[appicnc]

Hello Group

As memtioned I am working on a ATC, I have attached ( I think ) 3 photos of the almost finished prototype, as is usual some glitches have to be resolved but it appears to work.

I plan to drive it from a Makita trimmer, by toothed belt which will go onto the shaft below the " de-spinner ".

At the moment the arbor ( tool gripper ) is held be a 39mm dia' spring acting in compression, this may also change to a double acting air cylinder, a home built single acting cylinder provides the push to eject the tool holder.

The middle photo shows the arbor ( tool holder ) this was CNC machined as my skills don't run to that level of repeatibility.

The clamps are my castings and are an odd shape to allow for mounting on the Z axis, the clamps for the router ( each main part has 2 clamps, not 1 as shown- as I said, proof of concept ) are partly under the spindle and air cylinder - it will make sense when finished, or not

Any questions or suggestions would be most welcome.

Ed

[Guldberg]

Have you tried to run at high speeds yet? This i guess will be the critical part

[appicnc]

Hello Guldberg

Not yet, maybe later this week, I bought some toothed pulleys for the drive part before I had finnished the design process, the pulley has a dia' of 30mm with a bore of 20mm, I might try it but a bit more meat might be both safer and longer lasting.

I'll keep the group posted.

Ed

[turmite]

Hello appicnc

Good to see you start the thread. I'll be watching closely.

Mike

[Switcher]

appicnc,

How will you open/close the ATC (pneumatic/collet)?

I'm also very interested in your thread!







.

[project5k]

yea.... neat..... um, i dont get it.. im looking at the pics, and i dont understand what im looking at..

[appicnc]

Hello Switcher,

The collet is held / retracted by a spring in the 2nd large part, when a tool change is required air is fed into the cylinder which pushes against the spring. releasing the collet ( and tool ) when a new tool is selected the air is withdrawn and the collet is held by the spring.

I was speaking to the machinist who is making the collets for me and he told me how HASS do it, similar but the spring is on the main spindle so you don't need to de-spin the cylinder ( the de-spinner is the cone shaped AL part with the bearing in the camera end )

Hope this helps.

Project5K,

Keep watching, All will be revealed in due course.

Ed

[turmite]

Ed can you explain the term de-spin? I'm only familar with atc's from what I have learned here on the zone and that is not a term I have heard.

Mike

[Switcher]

Originally Posted by appicnc Hello Switcher, The collet is held / retracted by a spring in the 2nd large part, when a tool change is required air is fed into the cylinder which pushes against the spring. releasing the collet ( and tool ) when a new tool is selected the air is withdrawn and the collet is held by the spring. I was speaking to the machinist who is making the collets for me and he told me how HASS do it, similar but the spring is on the main spindle so you don't need to de-spin the cylinder ( the de-spinner is the cone shaped AL part with the bearing in the camera end ) Hope this helps. Project5K, Keep watching, All will be revealed in due course. Ed

I run a Schutte 5-axis toolgrinder at work, the spindle is about what you are describing here.

Well the collet on the spindle, stopped working about 2 weeks ago. A rebuilt spindle cost $23,000.00 installed. We got our money out of the spindle, the machine is 5years old and runs 24/7. Most of the stuff I do is resharpen carbide coolant drills, If the machine is down, it cost $85.00 to send each drill to an outside company to have it cleaned up, we average about 400 drills a week. So really that rebuilt spindle price ($23,000.00) isn't all that much.

Anyway, I think all that happend was the spring inside that spindle, broke!
The collet on the spindle is kinda cool, when it is locked onto the arbor it is expanded twice it's diam.

I will tell you this, that is one hell of a strong spring on that spindle!

I think it's cool your building your own ATC, only because that option on every machine I've seen, is expensive. A DIY ATC would be very useful.

Good luck, & keep us updated on your progress.







.

[Switcher]

appicnc,

Will you be running this ATC with Mach3 ?

If so you might want to have a look at this video (you might have already watched it).

http://www.machsupport.com/ToolChange/Tool_Change.html

--------------------------------------------------------------------------------------------------------------

How many tools you planning on changing with this ATC? The video mentioned possible over 200 (with Mach3)! Wooooooooo Doggy!!



.






.

[Switcher]

Another member is working on a lathe with ATC.

http://www.cnczone.com/forums/showthread.php?t=27031





Also check this link out:

Translated with Google:
http://64.233.179.104/translate_c?hl...language_tools

Homepage:
http://www.cnc-projects.de/Frames/Haupt.html







.

[appicnc]

Thanks for the pointer,

I looked at the vid' Ahhhhh!.

The ATC is a bed type ( I think ) in that the tool holers are placed along an axis, I am plannin on putting them on the Y axis on 50mm centres, so in theory I could have about 12 across and if on 50mm centres on the X axis, I could have another 24 rows, so 288, like all plans I am thinking on only 5, but I think once it's working then 5 won't be enough,( better than one though )

I have all the parts now and most of the maching is finished, the left to do stuff is minor but will take longer than I think ( it allways does ) but I am hoping to have the spindle running tomorrow afternoon or evenning and if no major problems on the machine Sat / Sun, I think having the air cylinder not attached to the spindle is a better way to go even if it is a bit more work at first - it should be more reliable.

Thanks again for the input - don't be offended by the 288 answer, I had never thought of a max' number but it is a valid question.

Ed