Sheet conveying apparatus and image torming apparatus provided therewith

摘要

To provide an image forming apparatus which is configured in such a manner that, when its system needs to be altered, functions needed to be altered alone can be added to/replaced by original ones, thereby a cost of altering the system can be held down and alteration of the same can be simplified. The configuration includes a rotor to which torque in a fixed direction is transmitted and transmitting unit for transmitting torque to the rotor, and the transmitting unit is replaceable by second driving unit capable of freely rotating the rotor in both forward and backward directions.