Electrophotographic apparatus

摘要

A large number of copies of a small original document such as a card are made quickly by forming electrostatic images of the document circumferentially spaced from each other on the periphery of a rotating photoconductive drum. The electrostatic images are repeatedly developed and the resulting toner images are transferred to respective copy sheets to form copies. In this manner, a number of copies equal to the number of electrostatic images on the drum are produced for each revolution of the drum. However, due to unavoidable discharge of the electrostatic images the same can only be developed a predetermined number of times if acceptable copies are to be produced. The present apparatus therefore comprises an automatic means for forming new electrostatic images when the original electrostatic images have been developed the predetermined number of times. The automatic means may be in the form of a counter, a timer or a voltage sensor. An indicator is energized when the last required set of electrostatic images has been formed so that the original document may be removed from the apparatus. The developing means is de-energized after the last required developing operation has been completed.