Driving device and image forming apparatus including the same

An electrophotographic image forming apparatus comprising:

• a main body comprising:
• a photosensitive body on which an electrostatic latent image is formed, and
• a developing roller configured to supply toner to the electrostatic latent image;
• and
• a driver configured to drive the developing roller and the photosensitive body, the driver comprising:
• a motor configured to provide a rotational force;
• a first gear connected to one of the developing roller and the photosensitive body;
• a second gear connected to the other one of the developing roller and the photosensitive body;
• a power transmitter configured to selectively transfer the rotational force from the motor to the first gear and from the motor to the second gear;
• a cam configured to set the power transmitter to one of:
• a release mode in which the rotational force from the motor is disconnected from the first gear and the second gear,
• a first connection mode in which the first gear is connected to the rotational force from the motor and the second gear is disconnected from the rotational force from the motor, and
• a second connection mode in which the second gear is connected to the rotational force from the motor and the first gear is disconnected from the rotational force from the motor;
• and
• a clutch configured to selectively transfer the rotational force from the motor to the cam.

An electrophotographic image forming apparatus comprising:

• a main body;
• a developer cartridge attachable to the main body and comprising:
• a photosensitive drum,
• a developing roller configured to supply toner to an electrostatic latent image formed on the photosensitive drum,
• a first coupler connected to the developing roller, and
• a second coupler connected to the photosensitive drum;
• a driver comprising:
• a motor configured to provide a rotational force;
• a first gear connected to one of the first coupler and the second coupler;
• a second gear connected to the other one of the first coupler and the second coupler;
• a power transmitter configured to selectively transfer the rotational force from the motor to the first gear and from the motor to the second gear;
• a cam configured to set the power transmitter to one of:
• a release mode in which the rotational force from the motor is disconnected from the first gear and the second gear,
• a first connection mode in which the first gear is connected to the rotational force from the motor and the second gear is disconnected from the rotational force from the motor, and
• a second connection mode in which the second gear is connected to the rotational force from the motor and the first gear is disconnected from the rotational force from the motor;
• and
• a clutch configured to selectively transfer the rotational force from the motor to the cam;
• a first output gear connected to the first gear by an even number of gears, connected to the second gear by an odd number of gears, and connected to the first coupler;
• and
• a second output gear connected to the second coupler, connected to the motor, and disconnected from the power transmitter.