Mechanical Resonance (Projects)

[tinman]

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.

Yes,that is on the cards.
At the moment,im trying to come up with a more efficient kind of transformer,biggest problem being it has to be an air core type.

Im leaning toward a cylindrical magnet accelerating through the center of the coil,where it becomes the core it self.


Brad

[verpies]

Im leaning toward a cylindrical magnet accelerating through the center of the coil,where it becomes the core it self.

That's really hard to do mechanically without reciprocating or whole lot of rolling friction!
...but I noticed, that you are pretty good in solving mechanical problems.

Whatever you do, please keep any metal conductive holders of the magnets, away from the varying magnetic field of the coil or the Eddy currents will cause significant energy losses in the metal holders  (even if the holders are not moving).  I know my stuff, too 

[Magluvin]

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.

I agree that there is some loss there. Back when TK had the wipmag vids, he had 2 small aluminum spacers set at particular positions around the rotor and closer to the CCW stator mag. He called them something like magneto iso kinetic dampers that gave a slight drag to regulate the assy when running due to the CCW stator would cut out of sync at higher rpms.

But for now lets see where we get with what we have and we can even test the issue by replacing the mags with weights of the same nature and see if one rings longer with or without the mags where they are. I can set up a mag lower on the fork closer to the base and send a ping pulse to the coil. Will be interesting.

Yes the voltage increase is interesting. For any particular coil  with a speed consistent magnet pole pass will produce a particular voltage. And for that coil used, and the open voltage it produces, the current capability should be predictable, for a given field strength and speed of the pass. So Im thinking that if the 2 coils are identical, with identical magnets for the drive and the pickup, and both mags moving at the same speed, I would expect less on the output coil. But I dont have that. I have more.
So in my mindset, I have to consider going for the best in/out voltage ratio as best I can first. I think that considering what I said above, if the output voltage gets to be higher than the input, the higher the better.

Another thing Ive tried with the previous magnet setup is to short out the pickup coil. It just about kills off the vibration. But then retuning input freq brings it back close to full throw. I like that also. 


But as we all know, this is interesting, but more testing as we go along will show what it shows. 

Mags

[Magluvin]

Yes,that is on the cards.
At the moment,im trying to come up with a more efficient kind of transformer,biggest problem being it has to be an air core type.

Im leaning toward a cylindrical magnet accelerating through the center of the coil,where it becomes the core it self.


Brad

I had read that for an air core transformer, it is best to wind the primary as the outer layer and the sec as the inner layer. Just a tidbit. If the windings are the same ratio, that could be tested as to what is better.

Mags

[Magluvin]

That's really hard to do mechanically without reciprocating or whole lot of rolling friction!
...but I noticed, that you are pretty good in solving mechanical problems.

Whatever you do, please keep any metal conductive holders of the magnets, away from the varying magnetic field of the coil or the Eddy currents will cause significant energy losses in the metal holders  (even if the holders are not moving).  I know my stuff, too 

There is yet another problem, that may be instilled in their design purposely. The neo mags are coated with nickle, mostly. Then break one apart and the neo material is very low resistance, virtually dead short. So the mags are problematic in the same manner.


Mags