Image forming apparatus having a main assembly, a cartridge detachably mountable to the main assembly, and a fixing unit detachably mountable to the main assembly

摘要

An image forming apparatus includes a main assembly; a cartridge detachably mountable to the main assembly; a fixing unit detachably mountable to the main assembly; and an opening of the main assembly. When the fixing unit and the cartridge are mounted/demounted, the fixing unit passes through the opening, and the cartridge passes through a space in which the fixing unit is to be mounted and passes through the opening. When the fixing unit and the cartridge at the time of passing through the opening are projected onto a surface perpendicular to the mounting and demounting direction, a contour of a projected area of the cartridge is at least partly inside a contour of a projected area of the fixing device, and the cartridge passes through the inside of the contour of the projected area of the fixing device when passes through the opening.