1. Field of the Invention
The present invention relates to an image forming apparatus, such as a copying machine, a printer, a facsimile machine, and a composite machine having functions of copying, facsimile, and the like.
2. Description of the Related Art
Conventionally, as described in Japanese Unexamined Patent Publication No. HEI 04-356062, there exists an image forming apparatus comprising a drum unit including a photoconductive drum and a developing unit including a developing sleeve, the respective units being constructed as separate bodies and dismountably mounted to a main body.
Such image forming apparatus as described above comprises a chamber for dismountably mounting the respective units to a main body of the apparatus. On each of the opposite inner side walls of the chamber, guiding members to which guided members formed on the opposite exterior side portions of the respective units are engaged are formed so that the respective units are guidedly inserted to a predetermined mounting position in the main body.
However, such conventional image forming apparatus has a problem that operability for insertion of the respective units is not so good since it is difficult to distinguish an initial position of an insertion path of each guiding member in the case where the guided portion of each unit is engaged with the respective guiding portion in the chamber for replacement and such. Especially, improvement in operability for insertion of the developing unit is requested since the developing unit is frequently mounted or dismounted with respect to the image forming apparatus for fixing up jamming of paper sheets.
Further, it is requested to prevent the drum unit and the developing unit from being inserted in wrong order.