Re: [CAD_CAM_EDM_DRO] Re: weird DC motor

Dale Smith wrote:

>
> A motor with two sets of high current (16 gage wire) brushes
> running on two separate commutators is new to me. Multiple
> sets of brushes running on one commutator is common for
> high quality servo motors designed for low torque ripple.
> Many servo setups have a motor and tach on a common shaft
> with two separate sets of everything including brushes, but
> the tach brushes and wiring are typically much smaller.
>
> +++Everything appears to be equal and the exit points of the wires indicate the brushes may be 45 or 90 degrees offset from each other.
>
> The nameplate data seems out of porportion with the rest
> of the description. The current seems low for the size
> of the motor and the size of the wires.
>
> Oh, I did just remember one type of setup with a set of
> dual commutators.... a co-wound DC motor-generator like
> the type once used to generate the high voltage for tube
> type radios in mobile equipment. Not likely related to your
> stuff because they were still different size brushes on
> the two ends and because your motors seem to have tachs
> or encoders on them.
>
> +++That would be a dynamotor.... My dream back in the '50s

Electrocraft made motors like this under the "Motomatic" series.
One winding was used as a tach, the commutators were on opposite
ends of the shaft, and the motor and tach windings were in the
same slots.

Jon