Can a Constant Force be Achieved with a Variable Spring?

[dE_logics]

Not necessarily a spring, I was looking forwards towards an arrangement so as to provide constant force regardless of the distance by which the thing has been pushed...just like a spring with variable k so as to maintain so as to maintain a constant force regardless of the distance it has deviated from it's mean position (commonly called as x) (of course up till a limit).

Now, there should be no additional input energy involved (apart from the force which's acting on the spring/arrangement)...for e.g. a motor (which's active but not rotating will provide a constant force) is not the solution...it should be a conservative system.

 

[Yeti08]

I'm sure there are many ways to [over]design something like that, but http://www.vulcanspring.com/conforce.html" might be what you're looking for.

 

[russ_watters]

A really long spring will have an almost constant force...

 

[dE_logics]

These rolled ribbon springs, what exactly are their limitations...I mean, what's the maximum force after which the deflection becomes considerable?

Can they provide 2 or 3 tons with variation of like...0.2 tons at most with a distance of 10 ft?

If so how much space will they require?

An opposite case...can they provide like 4-6 lbs with at most 0.5 lbs deflection with a distance of 1ft?Can they be used as gym weight replacements (not the bars and dumbbells of course...other stuff)?

Finally, can they expand instead of applying force through contraction.

 

[Yeti08]

I'm not sure about the specifics. You'll have to check the specs from the retailers. The link I gave before let you spec one out I think. As far as expanding rather than contracting, I would guess no, but that's just my guess.

 

[dE_logics]

Humm..ok.

I did checkout various manufactures but they only make the thing on order...so they don't have any "predefined" limitations.

Thanks!