The invention addresses the problem of providing a steady drive to the
photosensitive drum when all loads are driven from a common motor. To
address the issue, the invention includes three drive trains. A first
drive train that extends from the drive shaft of the motor to the
photosensitive drum; a second drive train that extends from the drive
shaft of the motor to the heating mechanism; and a third drive train that
extends from the drive shaft of the motor to the toner cassette and
drives the toner feed elements contained therein. A first drive element
for each of the first and second drive trains is independently rotatably
mounted on a common axis. Positioned on substantially an opposite side of
the drive shaft is a first drive element of the third drive mechanism. As
a result, the forces applied to the drive shaft as reaction forces to
driving the various loads are substantially counterbalanced. Further,
because the first drive element of each of the first and second drive
trains are separate from one another in rotation, the second drive train
has no effect on the first drive train driving the photosensitive drum.