Image forming apparatus with driving mechanism for photoreceptor

Abstract

An image forming apparatus includes a process cartridge that incorporates a photoreceptor and a plurality of developing devices. The process cartridge is provided with a first driving shaft to drive the photoreceptor and a second driving shaft to independently drive the developing devices. When the process cartridge is mounted in the image forming apparatus which includes spaced apart first and second gears, the first and second driving shafts are coupled separately with the spaced apart first and second gears so that driving forces are separately transmitted to the first and second driving shafts. A flywheel is mounted on a third driving shaft that is coupled with the first driving shaft to drive the photoreceptor. Since the developing devices are constructed to receive a large number of different possible loads, the developers are placed in a condition where vibrations are created easily by the driving of the various possible loads. The driving of the photoreceptor is arranged to be independent of the driving of the developing devices so that vibrations generated by the driving of the developing devices are not transmitted to the photoreceptor. Furthermore, the flywheel is provided on the third driving shaft, and a third gear is mounted on the third driving shaft. Since the third gear is coupled with the first driving shaft to drive the photoreceptor, the rotation of the photoreceptor will be smoothed out by the presence of the flywheel.