Image forming apparatus having rotatable electrophotographic process unit

摘要

An image forming apparatus has two units which are engageable with a photoconductive element and provided with a substantially identical configuration. Various electrophotographic process devices including a developing device and a cleaning device and to be arranged around the photoconductive element are selectively arranged in the two units. The photoconductive element is passed over two rollers such that part of the element forms parallel flat portions. The two units and the photoconductive element are rotatable integrally with each other.