An electric toothbrush having a detachable brush head assembly including a
driven shaft that is driven by a driveshaft disposed with in a housing.
The driveshaft is part of or secured to a torsion bar that supports an
armature including a pair of magnets. An electric coil receives an
alternating flow of current at a predetermined frequency that causes the
magnets to be alternately attracted to the coil and causes the torsion bar
to oscillate in an oscillatory rotary motion.
