How brushed DC and AC motors are different?

Question

I know the brushed are less magnetic interfered, higher efficient, etc. But, how the DC and the AC of the brushed
type different? Sincerely.

Answer 1

AC motors use slip rings and brushes . AC current is changing direction at 60Hz. The slip rings maintain electrical contact with the coil while allowing the coil to rotate. Slip rings to do not provide any mechanical switching of the conductor path (wiring)

DC motors use a communtator and brushes. DC current is unidirectional, alway flows in the same direction. The commutator also allows the coil to rotate while maintaining electrical connection but with an important difference. A commutator will perform switching based upon the angle of rotation.
A communtator is a series of individual copper strip pairs. Where each individual strip in a pair is connected to one end of a coil. The commutator strips are electrically isolated from one another.

As the coil rotates the commutators conductive strips pass under the brushes. DC current is applied to the coil in one direction and as the coil winding of the motor rotates the communtator bars (strips) connect to pass DC current in the opposite direction in the coil.

In essence a commutator causes the DC current to switch back on forth in the motor winding of the armature(shaft). Thus by defintion The DC motor has AC in its armature windings when the motor is running. The frequency of this AC is a function of RPM and the number of poles....

Answer 2

AC motors contain slip rings which change the direction of the current flow in the inner circuit so that ultimately the direction remains same in the outer circuit. But DC motors don't contain any slip rings.