Image forming apparatus including a preventing mechanism for preventing a developing unit from rotating

摘要

An image forming apparatus including a development unit rotatably supported by a body of the apparatus and including a plurality of developing subunits and a plurality of replaceable developer containers each storing a developer to be replenished to a particular one of the developing subunits. Also included is a stepping motor configured to cause the developing unit to rotate in order to bring any one of the developing subunits to a developing position, a preventing mechanism configured to prevent the developing unit from rotating at a time of replacement of any one of the developer containers due to an unexpected change in a voltage or a current driving the stepping motor, and a locking portion included in either one of the developing unit and the body and an engaging portion included in the other of the developing unit and the body, in which the locking portion and the engaging portion selectively engaging with each other for preventing the developing unit from rotating. Further included is a door member opened when any one of the developer containers is to be removed from the apparatus or closed when development is under way. The locking portion and the engaging portion engaging with each other in mechanically interlocked relation to an opening movement of the door member. Also included is a moving device configured to cause the locking portion to engage with the engaging portion by mechanically interlocking the opening movement of the door member to a movement of the locking portion.