dancer control

[OkiePC]

thanks for the response..but still can't understand what a "dancer" do either looks like.

do you have any sample picture for this one? because just read this here..so got no idea what this is and what it looks like

The answer and the pictures are going to vary widely depending on the product.

http://pffc-online.com/webexclusives/tension-control-dancer-0409/

http://www.webtekuk.com/automatic_tension_control_system.html

http://www.google.com/search?q=web+...a=X&oi=mode_link&ct=mode&cd=2&ved=0CD8Q_AUoAQ

 

[jimmeade]

Normally when you set you’re max braking to your tension control on the Dancer Roll, it will be at the max pot position (or home). Analog
of 0-10 vdc or 4-20 ma. Minimum brake tension will be almost 0 psi
from air regulator. So by having your analog input card 0-10 0r 4-20
and your analog out 0-10 or 4-20 you can set your engineering numbers for what desired psi pressure needed for max and min brake, in the program, to control proper braking. It’s always important to have the correct tension or air pressure to dancer roll. Adjusting gain on regulator will give some tweaking to min-max. Since you have a 20sec decel and accel time there should be very little backlash with brake variations.
However, all the above suggestions are correct depending on your personal process.

 

[Christine1914]

The answer and the pictures are going to vary widely depending on the product.

http://pffc-online.com/webexclusives/tension-control-dancer-0409/

http://www.webtekuk.com/automatic_tension_control_system.html

http://www.google.com/search?q=web+...a=X&oi=mode_link&ct=mode&cd=2&ved=0CD8Q_AUoAQ

correct me please if i'm wrong...is the roller that guides the material is the one that called "dancer"?

 

[OkiePC]

@Christine, the dancer is the moving part of the system. It can absorb line speed changes by acting as a tinyu accumulator, it can apply tension, it can measure tension. it can be weight, and/or air, and/or spring assisted, it can even be a free hanging loop of product, and still be casually called a dancer signal.

The pivoting position of the dancer, or it's linear position in a linear arrangement, is probably called a dancer due to its behaviour in some situations historically. Without the dancer, sudden changes in velocity results in product or web breakage or at least distortion and poor quality.

@Davepie, I just re-read the thread, I missed that the dancer is pressure assisted. It the dancer horizonal or vertical? Can we get a sketch? You want to control unwind tension using two pressure controls with one operator input? What moves the dancer? is it affected by letoff diameter, or only changes in web speed/tension?

 

[Christine1914]

ah ok..now i fully understand what this dancer is..

thanks for giving me light OkiePC

 

[Plcwill]

This problem you have is an easy one. I had this setup when I worked at the Washington Times Newspaper for the web presses this system was part of our pasters. What you are trying doesn't really need PID. This all can without PID and if you what I can provide a basic program for you