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