Re: [usa-tesla] 1931 Nikola Tesla's Electric Car
>After the AC induction motor, we think that the greatest invention of1) A transmission (gearbox) is not used in electric cars.
>Nikola was the electric car. This was no ordinary battery driven car
>because this car took its power from the ether just like an automobile
>antenna picks up radio waves from the ether.
2) George Westinghouse died in 1914.
3) Check out the size of a '80 hp' induction motor.
(hint: we changed out a 1 HP at work, Wed morning....)
- I don't follow. The disk has a "contact point" that is commuting the
current path from one location of the edge of the disk to another. I
called that a modified chopped DC, for purpose of classification of the
motor operation. I do not see how your final paragraph applies?
From: Ed Phillips [mailto:evp@...]
Sent: Friday, September 21, 2007 4:46 PM
Subject: Re: Motor Nomenclature Re: [usa-tesla] 1931 Nikola
The homopolar motor has a continuous commutation, but it is still not,
in the disk anyway, a proper DC current, since it is constantly shifting
it's path through the disk. Good point, but I think it can be regarded
as a variation on an AC motor."
Don't agree - the electric field is always radial. If you had one
continuous outer contact all around the disk there would be no asymmetry
What I mean in the last paragraph is that as the disk rotates in the
magnetic field a voltage difference is induced from the center to the
periphery and that voltage difference is the same at any point in the
disk which is at the same distance from the center. There is no
fluctuation in voltage, just a steady voltage difference, hence no
alternating component. If you placed a very large number of brushes at
the edge such that they completely surrounded the disk you'd find the
same voltage between any one of them and the center and no voltage
difference between any of them. No chopping or anything like that.
With a single contact the current [not the voltage] is indeed shifting
around the disk as it rotates but with continuous outer contact there
would be no shifting at all and just a uniform current all the way around.
Somewhere I have plans for a very simple homopolar generator which
you can build in a few minutes - just a brass or copper disk with a ring
magnet mounted on it. Mount the shaft in the chuck of a drill press and
you can run such an experiment yourself. The one I made would put out a
current of several amperes at a few millivolts. Used a ring magnet from
a microwave oven magnetron and a brass disk about 4" diameter with very
crude copper brushes.