Mechanical Resonance (Projects)

[verpies]

@Tinman

Do you remember the time when I was helping you to build a circuit that recovered energy put into a stator coil in some kind of a rotary motor?

[Magluvin]

In my opinion, the stainless steel bars are not a good material for the tuning fork, because they are electrically conductive and they are immersed in the varying magnetic field from the coil.

Anytime you have a conductive material that is immersed in a varying magnetic field, Eddy currents get induced in it and they waste energy.


The tuning fork would be better composed out of glass rods ...at least the ends of the arms, that are immersed in the magnetic field.


P.S.
Are these coils air-core?

Hey Verpies

The magnets on the plexi tubes will be moving with the fork prongs. So if you look at the previous pics and how the mags are mounted on the ends of the prongs, these will be outward also. So the mags on one prong will be moving with that prong, but are fairly far away from the other prong, and the same for the other magnet assy on the other prong. So there should not be much losses there as the magnets on the prongs are moving with the prong they are mounted to. There would probably be more interaction between the 2 mag assy's than there is with the stainless.  Looking again at the previous pics, the mag disks on the inner side of the fork prongs are in repulsion as it helped rasise the freq by adding more spring action. This is why I havnt put the coils on the prongs with  the mags base mounted, as there would be more concern of what you are saying if the prongs are moving near the stationary magnet. But there are ways around it if it is an issue, say we could put plexi extensions on the prongs to get the mags away from the bars. Or glass as you suggest.

Yes the coils are out of car speakers.  The new mag assy's should provide more flux density through the windings than the way I was having the poles of the mags inline with the coils previously.  If these mag assy's increase efficiency, on the drive side and the gen side, we should have an increase in output voltage over the input, beyond what I have gotten already. Once I get to a point of that I feel I cant increase the output voltage vs input any further within reason, then I will start doing in/out power tests.  Like I said, with 2 identical coils, one driver and one pickup coil, using the same mags for each, to get higher voltage from the pickup than what is input to the drive coil(remembering the input is sine AC at low freq, below 60hz so far) is an important accomplishment to me.  The one thing that is making the connection between the in and the out is the mechanical resonant device. It is what is making the transfer from in to out.

Mags

I like the glass forks. Ive seen some out there.   

[verpies]

Yes, the eddy current losses in the metal could be even higher, but that does not mean they are low now.
Conductive metal is still immersed in a varying magnetic field from the coils.  That's lossy even if the metal is not moving.

That voltage increase is interesting, but voltage is not energy.  Resonant rise is known to increase voltage at the cost of the current, regardless whether it is a mechanical resonance or LC resonance.

Looking forward to further numbers.

[tinman]

@Tinman

Do you remember the time when I was helping you to build a circuit that recovered energy put into a stator coil in some kind of a rotary motor?

lol Yes,i do.
Why is that?

Brad

[verpies]

lol Yes,i do.
Why is that?

I was thinking, that in these experiments, it would also be good to recover the energy stored in the coil, at the end of each cycle - after the tuning fork arm was attracted fully in.