digital readout for bender...

[krymis]

i need advice and help on making an angle readout for my tube bender. right now i have a hydrolic ram pumping away but i have to always stop and put a protractor on the tube for a measurement. This means stoping the ram and walking oer taking the measurement and then moving back and forth. Very frustrating when you are getting close. What i want to do is make a readout to have infront of me that tells me the angle I am at. What is needed and how would i do it? I was thinking something along the lines of digital protractor with a degree readout....

[Al_The_Man]

What you could do is install a 360 pulse/rev encoder (or gear a higher one) on a shaft pivoted on the arc centre and an arm moved by the tube-former or other and feed it into a digital counter like RedLion Controls (DigiKey), some are scaleable, or if you are inclined you could make one up with descrete IC's.
Al.

[krymis]

where would i find something like the encoder? How would i get a readout display?

[Al_The_Man]

Encoders can be got on ebay, or manufactures like Renco.
The output type for an application like this is not critical, The readout, as I mentioned look at Redlion products, they must have a site, and can be got through DigiKey by mail.
You would want an up/down counter.
I have used similar setups for readouts for back gauge read outs for breaks and shears etc.
Al.

[lwalker]

The encoder/counter suggestion is a good one, but you'll need (pretty simple) circuitry to handle motion in both directions since the counter will have to know whether to count up or count down. Or you will have to rezero it every time you start a bend. Newark Electronics has a pretty good selection of stuff like this.

How accurate does the indicator need to be?

[mxtras]

Along the lines of Al's suggestion, I built a simple DRO using 600 PPR encoders and simple, scalable process counters last year - cost was about $35 each for the counters. I will grab some part numbers tonight and post up the info tomorrow if you would like the information.

I have many, many, many industrial, 600PPR encoders I would be willing to part with ($15 each? + shipping) to a suitable candidate. PM me if interested.

Scott

[Al_The_Man]

I have used the Durant line also (Newark), you need to look for a quadrature counter to be able to count up and down with an encoder.
Al.

[mxtras]

Originally Posted by Al_The_Man I have used the Durant line also (Newark), you need to look for a quadrature counter to be able to count up and down with an encoder. Al.

Ya know, you just think you have all the answers, don't you?




Actually, I am embarrased that I could not recall how I had counters that went up AND down. They were quadrature and they were Durant. So once again, Mr Man was right. I hate it when that happens.....



Scott

[NC Cams]

Red Lion has a website.

They also have quadrature encoders and bi-directional counters that pretty much plug and play. Their catalogs are fairly self explanatory.

There was a thread recently by member Panoz(?) or something like that and he was trying to do the exact same thing only with a tubing bender - the Red Lion stuff did the trick for him.

[One of Many]

On the surface of your description of the bender, you mention a ram. Is this a 3 point bending unit with the tubing shoe on the ram and rollers on the opposite side?

As Al has suggested a rotary encoder setup, I don't think this would work here if there is no rotary motion in your process. You can still use the quadrature Readouts and a linear encoder, but you won't get direct angle conversion.

You could create a bend factor chart for each diameter of tubing, but that doesn't sound reliable for a single bend spot on. Mulitiple bends could be very repeatable once you know a linear position to stop at. At least as long as the tubing bends consisitant considering all the variables it may be afflicted with.

Interesting project!

DC

[magma-joe]

Check this one out on Ebay, it even has an adjustable micro switch for repeat bends. http://cgi.ebay.com/NEW-BIG-BRUTE-PI...em230047652828

[krymis]

my setup is similar to the one on blind chicken....the only real changes i made were an air over hydralic pump and a stationary lower brace.