The bearing motor

[tinman]

   

So say if there is no drag. Is that the secret to a true lenzless gen? And if there is drag, what are we dragging against? The field itself, as these fields are all around us?  If so, then that is possibly the holy grail of solid state motion devices. If we can drag against it, then we should be able to produce motion with it by pushing and/or pulling against it, like a silent ufo, car, plane, etc.

Mags

I would need to see that to believe it.   If you take 2 disk mags and have them face each other say 1in apart, and the magnets are set up do they can spin on axis, if you spin one, the other wont spin. There is zero force on the other magnet to spin with the other.

First-in the above experiment,your magnets are to far apart,and you now have two flows in the opposite direction. 1 between the two closest faces-say north to south/top to bottom,and 1 between the two outer faces-north to south/bottom to top.
Second-you have no current flowing through the field,and thus the fields do not clamp to the source(magnet)

Likewise, we cant get the disk magnet to spin using dc through a wire, no matter the position or orientation of that current carrying wire. The field from the wire will only affect the magnet as a whole, not as if the field lines are teeth of a gear and torques the magnet into rotation.

This is because you havnt carried out the correct experiment.

The key idea of having the ring magnet mounted to the copper disk in a homo polar dynamo is the fact that the magnet rotates with the disk yet the disk still produces current.

But if we mount a magnet to the end of a coil and move the magnet and coil through space, what ever direction, we get no current in the coil

. So the solid ring magnet mounted to the copper disk and when they rotate together, current is produced in the disk, is a very very special case in point.

Incorrect.
If the coil is placed in the same position as the disc,and you electrically connect one end of the coil to the axle and the other end to an outer disc(brush contact ring),and you spin the coil/magnet combo as you would with a homopolar generator,current IS produced.

What attracts me to the idea of having the ring magnet attached to the rotating copper disk is the possibility of no drag when currents are sent to a load..

CEMF is still produced due to field clamping. When the magnets are fixed,and the rotor spins,the field clamping is between rotor and magnet. When the magnet spins with the rotor,field clamping is between the rotating magnet,disc, and the pickup brush assembly.<--This is the flaw in the homopolar generator.

Typical gens need increase in input as the load increases. But here with the magnet spinning with the disk, if we draw current from the disk, is there a need for more input torque to overcome drag/lenz? And if so, with the mag spinning with the disk, what is causing the drag if the 2 components are mounted and spinning as one?

Yes,more input torque is required-->explained above.

[Magluvin]

First-in the above experiment,your magnets are to far apart,and you now have two flows in the opposite direction. 1 between the two closest faces-say north to south/top to bottom,and 1 between the two outer faces-north to south/bottom to top.
Second-you have no current flowing through the field,and thus the fields do not clamp to the source(magnet)

This is because you havnt carried out the correct experiment.
. So the solid ring magnet mounted to the copper disk and when they rotate together, current is produced in the disk, is a very very special case in point.

Incorrect.
If the coil is placed in the same position as the disc,and you electrically connect one end of the coil to the axle and the other end to an outer disc(brush contact ring),and you spin the coil/magnet combo as you would with a homopolar generator,current IS produced.

CEMF is still produced due to field clamping. When the magnets are fixed,and the rotor spins,the field clamping is between rotor and magnet. When the magnet spins with the rotor,field clamping is between the rotating magnet,disc, and the pickup brush assembly.<--This is the flaw in the homopolar generator.

Yes,more input torque is required-->explained above.

UUGGH!   I dont think any of us are talking about the same things.

Ill have to make some illustrations. Cant do it now.  Working.

Mags

[gravityblock]

No ,i do not disagree

  Reversing the polarity of the externally applied magnetic field (PM) in a homopolar configuration will reverse the rotation direction (the force changes direction).  Do you disagree with this?

The force produced by the current carrying wire remains in the same direction. You have done nothing more than turn the motor upsidedown.

No ,it dose not.

No,regardless of which way the current is flowing,the rotation direction is set by the initial spin direction-->it is not determined by the direction of current flow. The right hand rule dose not apply here.

You do no such thing. Current flow remains in the same direction.

   

Because the lorentz force is not applicable in this motor in its current understanding.

Yes,but in the bearing motor we do not have to reverse anything in order for it to spin in the opposite direction.
The direction of rotation is the direction of initial spin before current is applied.

Remember, the force is perpendicular to both the electric and the magnetic field.  In the case of the bearing motor, the rotation direction determines the direction of the induced current and the direction of the induced magnetic field of that induced current.  Reverse the direction of rotation, and we reverse the field direction of the induced magnetic field which interacts with the applied current with a force that is perpendicular to both the electric (applied current) and the induced magnetic field in a direction according to it's rotational direction.  In addition to this, there is another force between the induced current generated in the rotating frame with the induced magnetic field of the applied current in the stationary frame.  You use the left hand rule for one force, and the right hand rule for the other force.

Gravock

[Magluvin]

Ok, taking a short break.

Here is what I know about a homo polar motor as with a ring magnet and a copper disk close to it on the same axis.

1  If the disk is able to spin and the magnet is stationary, when we apply current to the disk from the outer edge to the center axle, the disk will rotate, and the direction is input polarity dependent. Likewise, if we physically turn the disk, currents will be produced in the disk between the outer edge of the disk and the center axle.

2  If the disk is stationary, and the ring magnet is able to spin, applying current to the disk from the outer edge to the center axle, the magnet will not rotate.  Nor will there be currents in the stationary copper disk if only the magnet is rotated.

3  But if the magnet is attached to the copper disk, so both rotate together, applying current to the copper disk from the outer edge to the center axle, the assembly will turn as one. Likewise, if we spin the whole assy, currents will be produced in the copper disk as previously described.

These things are to do with faradays experiments. I believe the bearing motor is a way different monster.

An experiment of seeming importance here....
So, on the standard homo polar assy using a ring mag and a copper disk, where both are able to rotate freely on the same axis, but independently, if we apply current to the copper disk from the outer edge to the center axle, the copper disk should rotate. But does the magnet rotate also?

That would be an impressive experiment. And it would help understand these things much better.


Mags

[gravityblock]

Remember, the force is perpendicular to both the electric and the magnetic field.  In the case of the bearing motor, the rotation direction determines the direction of the induced current and the direction of the induced magnetic field of that induced current.  Reverse the direction of rotation, and we reverse the field direction of the induced magnetic field which interacts with the applied current with a force that is perpendicular to both the electric (applied current) and the induced magnetic field in a direction according to it's rotational direction.  In addition to this, there is another force between the induced current generated in the rotating frame with the induced magnetic field of the applied current in the stationary frame.  You use the left hand rule for one force, and the right hand rule for the other force.

Gravock

There's no evidence of a net force between the electric field of an applied current with the induced magnetic field of that applied current in a current carrying wire.  This is because both the electric and magnetic fields are in the stationary frame.  However, there is a force between the electric field of the stationary frame with the magnetic field of the rotating frame, and between the magnetic field of the stationary frame with the electric field of the rotating frame.


Gravock