Hydraulic press brake control

I've purchased a Hydraulic press brake that the valve system was rusted and non repairable. My answer is to use glass scales on each cylinder for synchronization and height control. Originally I tried to use a arduino but it cannot count the encoder / glass scales and do other math at the same time fast enough. My budget doesn't allow for expensive servo valves so I made my own stepper driven two spool valve. I'm looking to use linuxcnc and mesa to make it work. I've built 3 machines so far using linuxcnc and mesa and have always thought of a better way to do it after I'm done. So I'm asking for input on what cards and concepts to impalement it using linuxcnc. As of right now I have linear glass scales attached to each side. and stepper motors have encoders as well. So I need to be able to read 4 encoders and drive to stepper motors back and forth to raise lower and sync.

Hi Steve,

Nice idea !

In the past i have made 3 press brake's my self. The last one was 3000mm 100 ton's with ltp1/parport cnc application running
on Mach3. I have used this press brake for about 1.5 year. It was a quite nice machine and worked with 2 air-hydraulic pump set's
on 800 bar. So i had 2 air valve's to pump the left and right cilinder separate. The height controlling was done by 2 stepper motor's and 2 inductive sensor's. It was a very simple system, but it worked good.

In your case i think when you have connected your lineair glas scale's and stepper motor's and it is configured and working on a Mesa card, it would be handy to make a custom screen layout for your press brake. Also i would make a C component for your press brake
application. When this is done, you can have a application like the Dutch supplier Delem.
www.delem.com/index.php?p=producten

The Delem interface is written in pure C code.
I am interested in your application, so maybe i can help to make a screen design and a c component for the linux society when you have your mesa i/o working.

sounds good. I'm thinking I'll use a use a 7i92H with 7i85s for the encoders and step control and a 7i75 for the i/0's. It's to bad they don't make a single board to do step gen, encoder and i/o's. They do for analog servo but not step gen. I think I can convert my code I wrote for the arduino into a comp pretty easy. When I get the hardware I'll update here. Thanks for your interest:)

Hi Steve,

See what we can do. We can make a gui for press brake control, with pictures of the state of the press brake.
Every state need's a picture. So it's just a little photoshopping and a good front picture.



Steve, you can look at the fpga board's of Mesa. Some board's can be almost adjusted unlimited. It need's some experience.
An other way is to make your own fpga interface. I am looking for that.

If you can make the ethernet connection's and the flash it for linuxcnc.... You are almost done for 19 dollars.
I mailed the seller if it's possible to make the ethernet connection for linux. Maybe they can help a little bit to start this board up.


Steve,

I think I can convert my code I wrote for the arduino into a comp pretty easy

Have you ever used a working machinekit arduino setup for your press brake concept? So yes, give me the source link. I can look for reverse integrating source code back to linuxcnc.

I have never use machinekit. I talked to Peter today at mesa. He helped me figure out what I needed. I ordered a 7i96 and a 7i75. He also mentioned that mesa has some new boards coming out. the new 7i95 will have step gen and encoder inputs. It's still in prototype stage though. I have a 7i96 in my plasma table so I've some experience with it. I have to figure out how to move the steppers with encoders only aprox 60 degrees each way to control spool valves that run the cylinders to sync, go up and go down.

If you want synchronised 2 valve control with 2 glass encoders, you have to write a component. Its quite easy for me to make a setup component. Can you give me all your wishes? Input and output signal list. And how you want to control your pressbrake at the user gui?

It would be handy if pcw calls me or mail later this week. Then he can advise wich fpga board i can order. I need something for 6 axis stepper with i/o. I prefer to start wich difficult fpga board that is suitable and has one working hal example.

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