At a recent OTC show in Houston, SWACO, a oilfield services contractor, was
showing off a mud centrifuge with a unique drive system. It consisted of a
flywheel with rare earth magnets mounted on it and a solid copper flywheel
opposite it. The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two flywheels
close together, both would spin at the same speed. As they were seperated the
driven flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch. Picture the
implications of this in the auto industry future. Never realized that a
magnetic field would affect copper. I'm talking about a 100hp(?)motor rotating
a 1000#(?) centrifuge bowl and rotor

For more info checkout : www.magnadrive.com
Very cool.
Jim

"GMasterman" wrote in message
...
At a recent OTC show in Houston, SWACO, a oilfield services contractor,
was
showing off a mud centrifuge with a unique drive system. It consisted of a
flywheel with rare earth magnets mounted on it and a solid copper flywheel
opposite it. The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two flywheels
close together, both would spin at the same speed. As they were seperated
the
driven flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch. Picture
the
implications of this in the auto industry future. Never realized that a
magnetic field would affect copper. I'm talking about a 100hp(?)motor
rotating
a 1000#(?) centrifuge bowl and rotor

GMasterman wrote:

At a recent OTC show in Houston, SWACO, a oilfield services contractor, was
showing off a mud centrifuge with a unique drive system. It consisted of a
flywheel with rare earth magnets mounted on it and a solid copper flywheel
opposite it. The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two flywheels
close together, both would spin at the same speed. As they were seperated the
driven flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch. Picture the
implications of this in the auto industry future. Never realized that a
magnetic field would affect copper. I'm talking about a 100hp(?)motor rotating
a 1000#(?) centrifuge bowl and rotor
The E & M fields are powerful. Sounds neat.

One wants something like that in the oilfield - no sparking. Induced currents.
I noticed a number of new designs in a magazine I get at work - Hope I have it still -
the ends are speed control and all sorts of fancy stuff.
Guess the industry has thought energy saving or something.

Martin

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

not totally true that "no energy is consumed" - there is IR loss in the
copper because there is a finite resistance -- now if you used a
superconductor then it might approach zero
"GMasterman" wrote in message
...
At a recent OTC show in Houston, SWACO, a oilfield services contractor,
was
showing off a mud centrifuge with a unique drive system. It consisted of a
flywheel with rare earth magnets mounted on it and a solid copper flywheel
opposite it. The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two flywheels
close together, both would spin at the same speed. As they were seperated
the
driven flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch. Picture
the
implications of this in the auto industry future. Never realized that a
magnetic field would affect copper. I'm talking about a 100hp(?)motor
rotating
a 1000#(?) centrifuge bowl and rotor

"GMasterman" wrote in message
...
The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two
flywheels close together, both would spin at the same speed.

Not quite lossless; anywhere you have the same torque (and torque input
supplied to the magnetic flywheel, must equal torque output from the copper
flywheel) and a difference in RPM, power is lost. If torque were higher on
the lower RPM shaft, then power would be conserved. But that requires gears
or belts.

In this case, the power is lost as eddy currents in the copper plate. Same
mechanical effect as friction in a normal clutch (with the exception that a
real clutch, when tight, won't have slippage!). Neat application of it
though.

Bit of trivia: that's exactly how they do tachs and speedometers. The
needle is spring-loaded and has a copper disc on it; a spinning magnet
(which is feed by whatever shaft) transmits torque to the spring based on
RPM, thereby causing the needle to deflect (based on the spring constant).

Tim

--
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- - - - - - - - - - - - - - - - - - - - - - --+ Metalcasting
and Games: http://webpages.charter.net/dawill/tmoranwms

GMasterman writes:

At a recent OTC show in Houston, SWACO, a oilfield services
contractor, was showing off a mud centrifuge with a unique drive
system. It consisted of a flywheel with rare earth magnets mounted on
it and a solid copper flywheel opposite it. The closer the rotating
magnetic flywheel gets to the copper flywheel, the more rotational
energy is transfered. With the two flywheels close together, both
would spin at the same speed. As they were seperated the driven
flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch.

Sure sounds like boob bait. No energy consumed, eh? Were they asking for
investors?

If you have any of those neodymium magnets around, try rolling one down a
thick slab of aluminum, or dropping one down the middle of a close-fitting
aluminum or copper tube.

GMasterman wrote:

At a recent OTC show in Houston, SWACO, a oilfield services contractor, was
showing off a mud centrifuge with a unique drive system. It consisted of a
flywheel with rare earth magnets mounted on it and a solid copper flywheel
opposite it. The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two flywheels
close together, both would spin at the same speed. As they were seperated the
driven flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch. Picture the
implications of this in the auto industry future. Never realized that a
magnetic field would affect copper. I'm talking about a 100hp(?)motor rotating
a 1000#(?) centrifuge bowl and rotor

Eddy currents in non-ferrous metals. Fun stuff.

Wanna baffle a lot of people? Drop a rare earth magnet down a piece of
aluminum pipe. Have them explain to you why it drops the way it does.

The same effect is used to damp oscillations on beam balances. The
faster the plate passes the magnet, the more resistance there is, and
there is no effect once the plate stops. Used on a lot of reloading
scales, among others.

Cheers
Trevor Jones

In article ,
Trevor Jones wrote:

Wanna baffle a lot of people? Drop a rare earth magnet down a piece of
aluminum pipe. Have them explain to you why it drops the way it does.

OK, having seen this type of mention twice in this thread now, and
lacking the ability to perform the "experiment" (Got some HDD magnets,
but apparently nothing suitable to drop them down - they just slid down
the aluminum flashing I tried. Big fat hairy deal...) I gotta know:

What happens? (Not the physics, electrical theory, etc, just the
physical "What am I supposed to see when I do it?")

--
Don Bruder - - New Email policy in effect as of Feb. 21, 2004.
I respond to Email as quick as humanly possible. If you Email me and get no
response, see http://www.sonic.net/~dakidd/main/contact.html Short
form: I'm trashing EVERYTHING that doesn't contain a password in the subject.

I worked on a small Renault in the early seventies that used a air gap
clutch with electromagnets. It was an interesting affair with radio tubes
in the control box.
All kinds of devices have been designed using eddy currents including
tachs as mentioned.... even dynomometers.
Lots of new designs using old ideas. Also old ideas like perpetual
motion/zero energy loss in new designs.
Randy

"GMasterman" wrote in message
...
At a recent OTC show in Houston, SWACO, a oilfield services contractor,
was
showing off a mud centrifuge with a unique drive system. It consisted of a
flywheel with rare earth magnets mounted on it and a solid copper flywheel
opposite it. The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two flywheels
close together, both would spin at the same speed. As they were seperated
the
driven flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch. Picture
the
implications of this in the auto industry future. Never realized that a
magnetic field would affect copper. I'm talking about a 100hp(?)motor
rotating
a 1000#(?) centrifuge bowl and rotor

Don Bruder wrote:
In article ,
Trevor Jones wrote:

Wanna baffle a lot of people? Drop a rare earth magnet down a piece
of aluminum pipe. Have them explain to you why it drops the way it
does.

OK, having seen this type of mention twice in this thread now, and
lacking the ability to perform the "experiment" (Got some HDD magnets,
but apparently nothing suitable to drop them down - they just slid
down the aluminum flashing I tried. Big fat hairy deal...) I gotta
know:

What happens? (Not the physics, electrical theory, etc, just the
physical "What am I supposed to see when I do it?")
Get a magnet 'set' out of an old hard drive - the type that has two magnets
in a holder with a gap between the two.
Saddle this assembly over the edge of an aliminum plate (an aluminum framing
square is perfect for this).
By hand, move the magnets rapidly along the aluminum.
You will be able to feel the resistance.
Regards.
Ken.

--
http://www.rupert.net/~solar
Return address supplied by 'spammotel'
http://www.spammotel.com

I actually did this when I read about it on this NG. I bought a few rare
earth magnets, took 3 of 'em and stacked them up (be careful, they pull
together so hard it can pinch) and dropped them into a straight piece of
1/2" copper pipe. Actually, it's best to take a slug of steel and drop it
down first. Plunk. Then drop the magnets. They sort of float down gently,
taking several seconds. It's fascinating to watch.

I took the whole shebang to my son's physics teacher and told him "here's
a great classroom demo". He thought so too and I'll bet that gets shown
every year at the local junior high for awhile.

GWE

Don Bruder wrote:

In article ,
Trevor Jones wrote:


Wanna baffle a lot of people? Drop a rare earth magnet down a piece of
aluminum pipe. Have them explain to you why it drops the way it does.


OK, having seen this type of mention twice in this thread now, and
lacking the ability to perform the "experiment" (Got some HDD magnets,
but apparently nothing suitable to drop them down - they just slid down
the aluminum flashing I tried. Big fat hairy deal...) I gotta know:

What happens? (Not the physics, electrical theory, etc, just the
physical "What am I supposed to see when I do it?")

Don Bruder wrote:

In article ,
Trevor Jones wrote:

Wanna baffle a lot of people? Drop a rare earth magnet down a piece of
aluminum pipe. Have them explain to you why it drops the way it does.

OK, having seen this type of mention twice in this thread now, and
lacking the ability to perform the "experiment" (Got some HDD magnets,
but apparently nothing suitable to drop them down - they just slid down
the aluminum flashing I tried. Big fat hairy deal...) I gotta know:

What happens? (Not the physics, electrical theory, etc, just the
physical "What am I supposed to see when I do it?")

It drops in slow motion. In a vertical tube, the magnet will flutter
down at about half the speed of about any other object of similar
density that you can drop down the tube.

A magnet dropped down the side of a sloped sheet of aluminum will show
some of the same effect, but it really only shows well when you can drop
a washer or such, alongside the magnet.

Pretty comical to hear the explanations why, sometimes.

Cheers
Trevor Jones

"Tim Williams" wrote: (clip) Bit of trivia: that's exactly how they do
tachs and speedometers. The needle is spring-loaded and has a copper disc
on it; a spinning magnet (which is feed by whatever shaft) transmits torque
to the spring based on RPM, thereby causing the needle to deflect (based on
the spring constant).
^^^^^^^^^^^^
Once the needle reaches the balance point, the angular velocity is zero, so
the efficiency drops to zero. But, since the device is transmitting
information to the driver, the power-in is being converted to
intelligence--it ought to be possible to derive a conversion factor for
energy to information G.

Another eddy current effect is to put a small DC voltage on a 120 VAC shaded
pole motor. The rotor will sort of ooze around when you turn it by hand. I made
a great payout reel drag by using one of these driven by a swing arm
potentiometer controlling an LM317 voltage regulator. Very non-critical, but
worked much better than a friction brake.

Earle Rich
Mont Vernon, NH

Nothing new about it except the use of rare earth magnets and the variable
airgap. It is an eddy current drive that has been common in large
industrial drives since the 50's. In the original design, they used a
large variable electromagnet to provide the flux. They have been replaced
in most industrial uses today by VFD's since eddy current drives are so
inefficient in constant torque, large speed reductions. A plant I worked in
had 4, 500 hp eddy current drives controlling the screw speed in some
polyethylene extruders. As soon as VFD technology got cheap enough, they
were replaced with VFD's with a huge reduction in drive system losses.

Randy


"GMasterman" wrote in message
...
At a recent OTC show in Houston, SWACO, a oilfield services contractor,
was
showing off a mud centrifuge with a unique drive system. It consisted of a
flywheel with rare earth magnets mounted on it and a solid copper flywheel
opposite it. The closer the rotating magnetic flywheel gets to the copper
flywheel, the more rotational energy is transfered. With the two flywheels
close together, both would spin at the same speed. As they were seperated
the
driven flywheel would slow down, and with enough gap, completely stop. No
energy comsumed to operare as a variable speed tranny and clutch. Picture
the
implications of this in the auto industry future. Never realized that a
magnetic field would affect copper. I'm talking about a 100hp(?)motor
rotating
a 1000#(?) centrifuge bowl and rotor

Wanna baffle a lot of people? Drop a rare earth magnet down a piece of
aluminum pipe. Have them explain to you why it drops the way it does.

OK, having seen this type of mention twice in this thread now, and
lacking the ability to perform the "experiment" (Got some HDD magnets,
but apparently nothing suitable to drop them down - they just slid down
the aluminum flashing I tried. Big fat hairy deal...) I gotta know:

What happens? (Not the physics, electrical theory, etc, just the
physical "What am I supposed to see when I do it?")

Try something thicker than aluminum flashing. (To be sure, I just tried it
with a HDD magnet on the back a piece of aluminum t-track and it worked
great.) The magnet should slide down abnormally slowly. Compare by sliding
a coin or something. It's way cool!

- Owen -

I just recently acquired a exercise type bike that worked on this same
principal. It would turn the one heavy flywheel without any physical
connection by way of belts gears chain etc. It was weird until I
finally discovered there was a series of nice magnets in the one wheel
that caused the other wheel to rotate. Right now its in pieces looking
to be turned into another home brew something or other.........



On 22 Apr 2004 03:07:56 GMT, (GMasterman) wrote:

===At a recent OTC show in Houston, SWACO, a oilfield services contractor, was
===showing off a mud centrifuge with a unique drive system. It consisted of a
===flywheel with rare earth magnets mounted on it and a solid copper flywheel
===opposite it. The closer the rotating magnetic flywheel gets to the copper
===flywheel, the more rotational energy is transfered. With the two flywheels
===close together, both would spin at the same speed. As they were seperated the
===driven flywheel would slow down, and with enough gap, completely stop. No
===energy comsumed to operare as a variable speed tranny and clutch. Picture the
===implications of this in the auto industry future. Never realized that a
===magnetic field would affect copper. I'm talking about a 100hp(?)motor rotating
===a 1000#(?) centrifuge bowl and rotor

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