How Can I Ensure Constant Tension on a Bobbin with an Electric Motor?

[brout]

Here's my main problem to concieve a bobbin machine...

I've got an electrical motor which provides a constant rotating vitess.. and i want, in the end, to make the bobbin rotating and assuring a constant tension on the wire. If you have any idea of a simple mechanical system to do that... thanks ;)

I don't know if that's clear enough.. first sorry for the possible english mistakes ;) .. then i haven't totally understand myself

Thanx anyway...

 

[brewnog]

Ok, from what I can gather you are trying to wind string onto some kind of spindle (I can't say I know what you mean by a vitess). Is the bobbin going to be rotating at constant speed?

How critical is it that the tension is constant? You might want to have a look at things like fishing reels. Try the Shimano website, I seem to recall it was good for technical info about bike components.

 

[brout]

Thx for the information...
just to be clearer i'll try to explain the problem more precisely.
So, as you guessed, i meant that a constant rotating speed (instead of vitess :S) is provided by the motor. But the wire arrives from an extrusion machine with a certain speed (maybe not constant). Then without any specific system the tension will depend on this speed and the radius of the reel. Here's the problem...
I've eard that a simple system exists (like one used in magnetopones...) but i can't find anything about it..

 

[brewnog]

Ah, you meant speed, as in the french 'vitesse', I get it...

How tightly does the wire need to be wound on the reel? Would having some slack between the drum and the extrusion machine provide enough tension, this would also allow for the extrusion speed not being constant.

 

[brout]

well.. there's no real precision about the tension.. only that it also have to be reglable, so it might have to be wound tightly i presume.
As far as I've understand my problem :) I need something that regulates itself, like something disconnecting when it is forcing too much.. but it's quite confused in my mind as you may have seen.

Also I'm only in a second year of engineer school, so I'm not looking for too evolved technical system...