Shake-em-up flashlight generator

[gyulasun]

I bought a couple of these torches cheaply at a car boot sale. They were fitted
with 2032 batteries which do not recharge at all. What sort of capacitor
circuit should I use instead?
Paul.

Hi Paul,

If your torches include the cylinder magnet and coils to be able to induce voltage at all, then I think you have a good chance to build in a schottky diode bridge plus one or two so called supercapacitors.
See this link for explanation and schematics etc: http://www.discovercircuits.com/H-Corner/shake-chgr.htm

To get an insight how much supercapacitors cost I think you may wish to look at Farnell for instance http://www.farnellinone.com/ in your country, then write supercapacitor in the Product Search window at top of that page and study the results. Unfortunately the cheap type supercaps of 5V or 5.5V have got a rather high series inner resistance/impedance (around 30,  75 or 100 Ohms),  though you can consider putting some in parallel to reduce their resultant impedance and increase their capacity for a desired lighting time length. Supercaps of 5V with less than 1 Ohm inner impedance do exist but of course they cost rather more.

Of course you may wish to search for other vendors to find the cheapest supercap source for yourself.

rgds,  Gyula

[Koen1]

Or you may want to use normal capacitors...
After all, I can imagine supercaps being usefull if you really want to
shake your flashlight now but only use the generated energy later,
(since supercaps can act like a battery in that they can store charges
more efficiently than normal capacitors, but act like caps in that they
can 'absorb' and 'release' the charges very fast like capacitors do)
but if you simply want to turn your fake shakeable torch into a true
"Faraday" shakable torch, they are not really necessary.
What you do need is at least one strong permanent magnet that
you'll need to mount inside the coil in such a way that it can slide up
and down inside the coil when you shake it.
And a rectifier per coil.
You could stack several magnets in repulsion and somehow fix them
together, in which case you'd need a coil roughly the same thickness as
one single magnet and as many coils to cover the cylinder in which you
are going to shake the magnet stack. Each coil needs a rectifier (or two
diodes to make a rectifier). More magnets means more "flux lines" being "cut"
every time the magnet stack passes through a coil, resulting in more output.

But the simplest version is just a single coil, a single magnet, a single rectifier,
and a capacitor.
Rechargeable battery could be included to store charges, and that would need
a little more circuitry.
Supercaps could be used instead of the battery or the capacitor+battery.

[Koen1]

To get back to that first post in this thread;

That was clearly an attempt to design a similar setup, in which
the magnet is cuased to move up and down inside the "collector" coil
by alternately pulsing an electromagnet on either side of it.
Seems to me you'd be expending at least an amount of energy equal
to that produced in the "collector coil" every time you make the magnet
move by pulsing the electromagnet. And most likely quite a bit more.
Also, seems to me the magnet will get stuck at one electromagnet
as it contains an iron core and the permanent magnet will still be attracted
to that when the electromagnet is no longer active, unless you actually
push it away with a pulse of opposite polarity in the electromagnet...
... which obviously will take additional energy.
All in all, seems like an inefficient way to make the magnet move,
and even if that was an efficient way, you're using a coil to
move a magnet through a coil, using current to induce a magnetic
field which moves a magnet which induces a current... You'd be
better off using the feed current directly.
Or at least, that's what it looks like to me.

Nevertheless, if we do away with that suggested mains input,
and if we were to use a slightly different electromagnet arrangement,
we might be able to turn it into something cool.
So let's say we use a sort of "crystal radio" receiver to "leech"
energy from radio waves, but instead of simply using its coil as
a filter and using the amplitude modulation to feed the voice signal
to our speaker or headphones, we simply collect those fluctuations
in charge in a capacitor (with rectifier if needed).
We could have these charges accumulate untill they reach a certain
minimum value, then allow the cap to discharge (using a Zener diode
for example), and use these periodic discharges to for example make
the magnet move. (By feeding this pulse directly into the coil around
the magnet, thus making the magnet jump up)
We don't need two electromagnets on either side of the magnet to make
the magnet move. We only need the coil around the magnet.
We also don't need to pull the magnet back down, we've got gravity doing
that for us. So we only need to give the magnet a good "kick" up,
it will drop down by itself.
And yes, although we might be able to use electrical charge collected
by using a "crystal radio" circuit, the efficiency of the magnet+coil
arrangement will still be far below unity, obviously.

But now, what happens when we use a second magnet at the bottom of
our cylindrical setup (I am assuming here that we have wound the coil(s)
around a cylinder with the magnet inside it, and the cylinder standing on one end),
which is in repulsion to the moving magnet?
It is obvious that the moving magnet will hang suspended in repulsion above
this bottom "stator" magnet. It is also clear that the magnetic field of this "stator"
magnet will have the same field orientation as the coil does when it "kicks" the
moving magnet upward. So during this "kick", the "stator" magnet and the coil
align their fields.
As the current pulse fed to the coil stops, the coils field collapses, and the magnet
no longer experiences a "push" up, and starts to drop down to the bottom of the coil.
During the entire drop, it will induce current in the windings of the coil. Proper use of
rectifiers or diodes should allow for collection of all of that.

We might be able to increase the output by using a stack of magnets in repulsion,
but that would require a slightly different setup. For one, we'd need a number of
"collector coils" to make good use of the multiple field line orientations, and this would
result in a "collector coil" array that cannot be used as the "kicker" coil anymore.
So we'd need to create the desired magnetic field pulse in some other way.
Perhaps putting a coil around, under, or above the "stator" coil  (or a combination of these)
would allow us to produce a similar "kick" if we pulse that coil...
A second objection would be the increased weight of the moving magnet stack,
which would obviously need more input to actually move up the cylinder.
So the higher output would also mean a higher input, and the stacked opposing
magnets would mean the collector coils and the "kicker" coil(s) cannot be the same.
On the other hand, we may be able to use a second "stator" magnet atop the cylinder,
which should be in attraction to the moving magnet, but with a spacer in between so that
even when the moving magnet is closest to this top "stator" magnet and does "feel"
its attraction, the attraction is not strong enough to actually hold the magnet there against
the pull of gravity, and the magnet will drop down. This might reduce the "kick" power
somewhat.

Ok, perhaps I should have posted this in the "Half-baked Ideas" section??

Well, any reactions, suggestions, or other types of reply are most welcome!!!

Kind regards,
Koen

[ramset]

Was sent this today from an FE researcher


https://m.youtube.com/watch?v=oY-bD7kpbNw


All comments welcome
Hopefully some feedback on this actual claimants work?
Testing etc ...?
Respectfully
Chet K

[hartiberlin]

Probably too much friction all in all, he also could not show it in his videos, that he reall yachives more output than input...
These are different oscillation systems, as it is dependant from one water column going back and force through All the coupled outputs,
than for example the Rick Friedrich coupled LC coils...where there is really coming more power out as has been put in...as each coil can oascillate on its own frequency...

Regards, Stefan.