View Full Version : Data Entry During Machining


squarewave
01-25-2004, 03:39 PM
Is there any way to allow the user to input data while the machine is running a program?

In my wire EDM application, I need to be able to change the "E-Pack" number on the fly. This number ranges from 100 to just over 1000 and controls 11 sets of relays to vary the sparking parameters. Typically, you enter the workpiece with one low power E-Pack and switch to another higher power setting once the flushing is fully stabilized.

The QUESTION command doesn't function during machining, and typing in the TEXT box is disabled. If there is something already in the text box, then it is possible to read the variable. I have also tried to use these two methods during a FEEDHOLD, but they are still disabled.

Has anyone found a way to do this?

Al_The_Man
01-25-2004, 04:38 PM
I may be out in left field on this, but how many combinations are there? I assume the relays are already hooked in to assigned outputs, if so possibly installing a BCD switch in to four inputs gives you a total of 16 combinations, you then writing a i/o macro to control the output relays, depending on the switch position, similar to how a feedrate overide would work. What do you think?
Al

squarewave
01-25-2004, 05:29 PM
Al -

Thanks for the fast response! That would work well, except that each E Pack number controls 11 SETS of relays. Each set is 4 relays that form a 4 bit word to control the parameter (voltage, power, wire tension, wire speed, stabilizing circuits, etc). The Mitsubishi Machining Parameters book lists E Pack numbers up to about 1016, starting at #100. There are about 150 unused numbers, so there are probably 7-800 unique settings. To be consitant with the the machine documentation that correlates material type/thickness/surface finish/accuracy with the E Pack number, I would like to use their numbering scheme.

So, using your BCD idea, I need 10 bits (or 16 if it is configured as 4 bits per digit), which should get me to 1024. I could set the 4 wheels to the desired E Pack number then hit a button to read them and set the relays. I have 10 more inputs available on my I/O card, so this would work.

I was hoping for a solution that wouldn't add additional hardware. From a purely aesthetic viewpoint, since many of the early EDMs used thumbwheels for various settings, I would like to stay away from them. Maybe I can find an LED/LCD type on eBay if I can't get it in through the display!

Thanks again Al !

HuFlungDung
01-25-2004, 08:04 PM
I don't have my camsoft manual in front of me, but does the multifunction knob command have the same limitations? Perhaps you could load some presets into that, and control it with a couple of I/O points? I'm thinking of simple momentary contacts to increment the knob position up or down.

I'm assuming that you really only need a start and a run setting, and that you could preload the values into the multifunction knob? This might be a bit of a pain if you have to change these values a lot.

squarewave
01-27-2004, 09:23 PM
Thanks Hu. That would probably work also - but it would require the operator to plan ahead. I also neglected to mention that the feedrate needs to be changed as well. I can use the analog slider to do that, but that will require the user to calculate the percent increase required to go from the starting feedrate to the machining feedrate.

I was hoping that implementing the PC based control would provide more user flexibility and have a few less compromises in it. Don't get me wrong - I am very happy with the flexibility of the control software. However, one of my reasons for doing this was to hopefully retrofit some similar existing machines in the area, but right now it may be a tough sell.

When I get a little more time, I am going to try to do a FILEOPEN and a FILEREAD while machining. If that works, I can write a visual basic program with two input boxes - one for EPack and one for feedrate. The desired EPack and feedrate can be stored in a single line data file and then read in Camsoft with a button - just like you would a text box.

HuFlungDung
01-27-2004, 09:30 PM
SQ,

I only have a vague idea of what you are trying to do, but why can't all these things be written into your nc code? Is it imperative to have kind of a "jog" start to the EDM process?

Are you frantically looking through the manual trying to find the right EPAC number while the machine is acting up? :D

squarewave
01-27-2004, 09:57 PM
Theoretically they can be - but not all programming packages have this feature. Some that do call it a "power up" distance which is the distance that you believe flushing will be stabilized from the edge of the stock. At that point the nc code would insert a new epack number (much higher power) and a much faster feedrate. If your NC package doesn't include this feature, putting in an extra point at the right location with manual editing can be a little daunting, especially if you are in 4 axis mode and you are entering the workpiece tangentially in an arc motion. Obviously, in a production part you are very likey to take the time to put all of it in the code.

However, doing it on the fly is very easy. You have great visual clues at the machine for the flushing condition (upper and lower flowmeters). When both flows drop off, indicating most of the water pressure is now going around the wire through the thickness of the stock (instead of squirting down the edge of the part), you pop in the high power epack and faster feedrate. If you do this too soon, the wire overheats and breaks. Then you remove all the covers, raise the head and rethread the wire and try again.

HuFlungDung
01-27-2004, 10:16 PM
I suppose it would be an oversimplication to say the feedrate is the primary variable on which everything else depends?

You could incorporate logic that would trigger certain epac numbers to be issued whenever the feedrate reaches certain values. You would have to transfer feedrate override into your I/O though, so that the trigger events can occur according to the operator's feedrate override input.

Just suggestions, maybe it will give you an idea. :)

tom renzi
03-18-2005, 12:09 PM
I dont know much about E.D.M machining, but if u have user macro functions, couldn't you develop a variable based on condition?

Citron
03-19-2005, 03:54 PM
I found several prewritten EDM macro routines on my Camsoft CD. some are for sinker type EDM and others for wire EDM. there are sodick, japax and agie post too for their embedded CAD/CAM system.

I don't have an EDM so I don't know whats important but here is what macros are available on the CD they give you.

[Spark Gap]
[Wire Threading]
[Wire Feed]
[Wire Cut]
[voltage monitoring]
[Oscillation]

of course the source code for these are on the CD so they can be modified but create your own. I have for routers and mills. that's what find is so much better about Camsoft.

Johnny

intrusion
03-21-2005, 11:32 AM
SQ,

Would in not be better to have the control monitor the flushing and determin on its own when to change the EPACK value instead of relying on the operator to do this based on visual conditions ?

I think the upper and lower flow meters are a big clue here. Can you describe how these function. Are they connected to analog inputs on the motion card ?

If these are then you could monitor them with a TIMER file and based on the flushing (high or low pressure) you can build in some of your own knowlegde based machining stratagies to set the new EPACK value. This would be a series of IF THEN statements in the TIMER file.

I think the VB example is probably a good idea if you need to have the operator input values during machining. All examples and suggestions given in this thread seem pretty flexible to me.

intrusion :boxing: