Jump to content

Welcome to eMastercam

Register now to participate in the forums, access the download area, buy Mastercam training materials, post processors and more. This message will be removed once you have signed in.

Use your display name or email address to sign in:

Vacuum Workholding on an HMC


Guest
 Share

Recommended Posts

Looking through and considering setting up a vacuum on a tombstone.....wondering how others have done it?

I am wondering if anyone has come across a closed loop type system?  Load and charge it on the loading dock, then send it in to machine....haven't found much in air......looks possible on a hydraulic set up.

We have all Palletech lines so tombstones are moved to and from the loading stations by robot carrier....a manual connect/disconnect procedure could be a killer on this long-term....

 

Link to comment
Share on other sites

A pallet mounted venturii unit would be dirt cheap. For any hope of a pallet tech loaded tombstone you would also need a tank on the pallet plus a  good one-way valve to stop air ingress while venturii isn't getting an air supply.

the biggest deal would be getting a pressure signal to CNC for automation safety?

Link to comment
Share on other sites

John,

I've seen air line (positive) pressure systems before which creates the vacuum.

I'm assuming you want vac to hold a thin base/bottom of a part thickness? Ie clamp somehow else to secure (mightybite/pullback etc) and then vac to suck the bottom down to keep base thickness/finish?

So what about a positive air pressure system and have it hooked to an M code in the machine? Pallet loads in and sits waiting for operator to connect fitting, hit green button and prog activates mcode. Pressure switch to ensure air pressure could be hooked in quite easy?

BUT how the heck you'd automate it to load the pallet and connect the fitting automagically is beyond my payscale :D 

Link to comment
Share on other sites

I have done this but with manual connect disconnect venture system with tank inside tombstone. yes they did eventually hit station ready with hose hooked up and also tried running one that had sat loaded for a weekend (slow leak netted little or no vacuum left).

some kind of load unload cuppler might be  part of the solution?

Link to comment
Share on other sites

With some planning and good design work, you could probably sort out a way to tie into the machine's compressed air system using a set up similar to some old Cincinnati HMCs. We had one in our shop that coupled the air line to the pallet from the B axis through the bottom for an air chuck (had a face on top of the table that pressed against a matching face on the bottom of the pallet, with a gasket). Just use a venturi pump on the tombstone, like everyone else is saying.

 

Link to comment
Share on other sites
  • 2 weeks later...

a rotary union is what I used. instead of air pressure I plumbed all my vacuum lines through this...I did do some concepts with a shutoff valve on the vac table. It all worked as long as I NEVER had a vac leak. once a leak started vacuum was quickly lost.

FYI A vacuum pump will constantly draw @29.  A small pump or a large pump can only draw about 29. The small pump may only flow 2cfm & the larger ones 220cfm +. So a large pump will be able to handle a leak 10x larger than a small pump and not drop your part...more or less.

10 Pass Threaded Shaft Rotary Unions

  • Like 2
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.

Join us!

eMastercam - your online source for all things Mastercam.

Together, we are the strongest Mastercam community on the web with over 56,000 members, and our online store offers a wide selection of training materials for all applications and skill levels.

Follow us

×
×
  • Create New...