On Jun 26, 2009, at 5:25 PM, William Beaty wrote:
On Sat, 27 Jun 2009, John Berry wrote:
If we used a magnetized shaft, north at one end south at the other
would
this still be required to create the effect?
That would work. A magnetized shaft would turn it into a conventional
Faraday motor.
I think an axially magnetized shaft, by symmetry, would produce an
equal but opposite torque at opposite ends of the shaft, resulting in
no net torque, assuming radial symmetry exists as in the videos and
photos of the existing motors. The current goes radially in opposite
directions on each end, but the B field must go axially in one
direction at both ends, at a given radius, thus there is no torque
produced within the shaft or the bearings from the radial current flow.
I think the true driving force is due to hysteresis in the balls, the
rotating ring (ball race) and any magnetic material within the shaft
that is free to rotate and is near enough to the rotating ring. A
circular magnetic field H about the current i through the contact
point and vicinity induces a circular M field within the balls and
ring, i.e. circular about the radial current i.
As the balls and ring rotate the M field remains in position within
and relative to the ring, and thus the current then goes radially
through an axial M field which is comprised of the trailing edge of
the circular M moving into position to intersect the current. The i x
M force reinforces the motion of the rotating ring. The above is
also true with regards to the M fields within the ball bearings.
I have updated:
http://www.mtaonline.net/~hheffner/HullMotor.pdf
to improve the Figures 3 and 4, which illustrate the principles in
the above two paragraphs. I also corrected some erroneous text,
though the major principles are unchanged.
The faster the ring rotates the stronger the latent M fields are,
because the less time M must be sustained without an inducing H. The
faster the motor goes the more torque it should produce. This is the
opposite of the effect that would be obtained if the torque were due
to thermal expansion, i.e. a reduced torque with increased motion due
to the shortened heating/cooling time.
The motor should work with copper bearings or a copper stationary
ball race, but requires at minimum *either* a magnetic rotating ball
race and/or shaft, or magnetic ball bearings, and should work best
with all magnetic components. A magnetic ball race is more important
than magnetic bearings because there is a lot more magnetic material
involved. The motor should not work with copper balls, copper
rotating ball races, and a copper shaft.
The motor should not work as effectively with roller bearings because
the current is distributed over a wider area and the H field is much
weaker, thus the M field is weaker, and the current density is
weaker, thus the i x M force is much weaker.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/