The main coils also have shade coils. They are very high current
shorts. When the pole is energized the shade absorbs energy from
the pole. As the magnetic power is decreased the shade winding kicks.
This starts the turn as two are employed to twist clockwise and two
counter (or anti) clockwise. They are typically the heavy current copper
wires.
Martin [ who has a 4 pole DC motor :-) ]

wrote:
On Dec 12, 3:27 pm, "Stormin Mormon"
wrote:

Many times, motors just dry up. The draft inducer motor
dried up, on a friend's furnace. She lives alone,
unemployed, and has major medical problems. I was able to
disassemble the motor. Sand the shaft lightly with some
emery cloth. Remove the dried oil with Qtip and some WD-40.
Reoil it with Zoom Spout Turbine oil (you may substitute two
stroke mixer oil, if you wish). Reassemble, and it works
fine.



Second that. I recently disassembled the bathroom ventilators from
two bathrooms. The shaded pole motors would run after they got
started, but would not start running. The first one I just cleaned
and lubricated which did not fix the problem. The second one I added
a couple of very thin stainless washers to take the thrust. The
motors mount with the shaft vertical. That fixed the starting
problem, so I went back and did the same to the first motor.

The motors are reversible shaded pole motors. How could that be, you
say. Well they are actually two shaded pole motors on one shaft.
Energize one motor and it runs clockwise, energize the other winding
and it runs counter clockwise.


Dan