Patent ID: 8818211

Claim:
An image forming apparatus comprising: a motor; a mounting unit configured to receive a cartridge mounted therein, the cartridge having a detection target configured to be moved by a rotational driving force of the motor; a printing unit configured to print an image on a sheet using the cartridge; a detecting unit configured to detect the detection target at a detection position on a movement trajectory of the detection target; and a control unit configured to control the motor and the detecting unit, wherein the control unit is configured to perform: a rotation control process of: accelerating a rotational speed of the motor; rotating the motor at a constant speed in a time period when accelerating the rotational speed of the motor up to a target speed; detecting the detection target by the detecting unit in the state where the motor rotates at the constant speed; and accelerating again the rotational speed of the motor after completing the detection; and a determining process of determining at least one of a kind of the cartridge and a state of the cartridge on the basis of the detection result of the detecting unit.