Odd Q on machine stability

I've had to deal with this issue my entire working life Dan. High speed robotics is right at the core of the injection molding industry today. It is if you want to compete anyway, and you have the same issues to deal with in what EA is mulling over. Tool changers causing part imperfections has been a real issue in the milling industry right along.

In the mid 90's I bought a big beam robot out of the BK of a Texas molding company to use on a 630 ton Toshiba hydraulic press. All I wanted was the metalwork and we stripped it completely when it arrived. I replaced the air/oil drive with a fast pitch ball screw set that Beaver Precision built for me and hooked it up to a pair of Fanuc's high speed alpha series (3600 RPM) servo's.

The thing was lightning fast and worked pretty good until the vacuum chuck was holding the twelve pound part we wanted to remove from the machine. The vacuum wouldn't hang on to the part when the robot retracted out of the machine. I should have stopped and though about that for a minute but what I did instead was install a spring activated mechanical clamping system we cobbled together. The chuck would move in and when it grabbed the part, six fingers engaged to clamp the part from behind. I figured the part wouldn't fall of then, and it didn't. When the robot accelerated the part upwards I ended up with the entire mess sitting in what was left of the discharge shute at the bottom of the machine and a big old pile in my britches. You see, I hadn't bothered to set up the acceleration ramping time constants on the drives, only the decel so the servo just came on at 2000 RPM. The screws were six pitch. OOPSIE!

Anyway, I'm just poking fun at PV/EA/whatever.

The M3/M4 thing at ten percent below max RPM is something I actually do when commissioning a machine however. Busted the 35 Kw geared head on a Formosan machine once. Took about twenty minutes. Smoke everywhere. Sales guy had said you could reverse the spindle all day long at 3000 RPM when I asked him about rigid tapping. I guess they have really short days in Formosa...... That would also explain why all of these guys think they are well hung. Imagine what ten inches is if an entire day is 35 minutes long. LMAO

What ever happened to"sENOIR ManuaL" swinging the door every shot?

We had Wittman robots on the Engels - Sweeet! If there was one bad cavity they prgrammed it to drop that one in the scrap pile, while others were placed individually in trays. Cool shit. I did alot of EOA tooling for them whilst getting my wings on setup & processing. Those side robots are really freakin cool. Ever see the Engel training video, done here loacally at Winsler? Now thats a 1st class facility. They'd have black tie events on the molding floor.

-- ~g~

Dancing machines, eh? Thoughts? Well here's one.

How about putting a VMC within a cage so it can tilt back and work as a Horizontal with all it's attendant advantages? Opps, there go the tables and the tools in the carousel. :( OK, let's put a HMC within a cage to rotate it forward so it would be as easy as a Vertical to set up. Then tilt it back for machining. Eh? LOL

I can remember an ISS hard drive (600 megabyte monster - about the size of a dish washer) way back when dancing across the floor.

One of the monthly programs would make it cha cha cha!

EA:

Some shops try to isolate machining centers by mounting them on anti-vibration rubber mounting pads.

And conversely, some machining center's frames (either castings or weldments), are so light duty (read flimsy), that they NEED the extra torsional stability and rigidity that screwing them to the concrete floor affords.

O.K. Please explain what you would be pumping in from outside? Not much out there. :-)

Enjoy, DoN.