2.11.2017

Metal Brushed Oil Filled Motor Open Source Hardware Motor Invention

This invention can be termed "Coordinate Switching" (not to be confused with "coordinate motor" which is a separate but complimentary technology) This open source invention is about a metal (or metal based composite) brushed motor.  It can be any type of electric motor; AC, DC, or another type.  It doesn't have to be oil filled, it can be lubricated with anything but oil filled would be a typical version.

In a typical brushed motor graphite is used as a brush material.  This serves 2 purposes, first to lubricate the brush contacts to prevent damage and overheating and secondly to limit electrical shorting between the positive and negative terminals that the brush contacts with.

However graphite is a very poor conductor.  Not only is it a couple of orders of magnitude worse than metals (10^-6 vs 10^-8 resistivity) but also transverse to the graphene sheet plane graphite is 3 more orders of magnitude worse.  Dennis Berube countered that problem of adding multiple wires into the brush reducing the need for transverse electron flow with great success.

If metal were used instead of graphite we would have astronomical increases in conductivity but also a few issues would arise.

1. friction.  Graphite on graphite has a 0.1 frictional coefficient.  Copper on copper is 1.  So that would mean to use copper we would have 10x more friction and much more heat produced.  This can be countered by having oiled brush contacts which would bring copper down to even better than graphite at 0.08.  This could be achieved by most probably oil filling the motor (which can also be used to help cool the motor just like a traditional motor is cooled) or just any method that achieves oiling the brush contacts.

2. Shorting.  From what I have seen a single brush for some length of time during the rotation contacts and therefore shorts out the positive and negative commutator segments.  This isn't such a big deal for graphite brushed motors because not only is the conductivity of graphite just pretty low to begin with but across the graphene sheets like we said is even worse.  If we want to use metal brushes this limitation can be countered by having multiple offset commutators.  So basically in a metal brushed motor the brushes would simply not be big enough to contact both proximal commutator segments at the same time.  This would mean you would need multiple rotationally offset commutators (or one commutator designed to acbieve the same effect)so there are no "dead zones" where the rotation could be and the motor can't start or produce torque.






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