On 10/4/2015 1:51 PM, Don Y wrote:

It's called a universal motor , and it will run on either AC or DC . There
are 2 flavors of universal motor , series wired or shunt wired . I don't
remember why each is more desirable for certain tasks .

It's almost definitely series wound. They're good for high speed *and* being
able to vary speed by varying the applied voltage (e.g., with something
akin to a "dimmer circuit")

To be more explicit: an AC induction motor runs at a speed determined
by the motor's winding geometry (which is fixed at time of manufacture)
and the frequency of the AC voltage applied. Varying the speed is done
either with mechanical gearboxes *or* a VFD (Variable Frequency Drive).

For small household appliances (drills, blenders, etc.) that desire some
sort of speed variation, an induction motor is impractical: the electronics
required to vary the frequency are more complex (than simply varying the
voltage)