Abstract: A transfer nip is formed between a transfer member and a photosensitive drum. The transfer member is configured to transfer a toner image formed on the photosensitive drum to a sheet that passes through the transfer nip. A humidity sensor is configured to detect humidity. A sheet sensor is arranged upstream of the transfer member in a sheet conveyance direction. The sheet sensor is configured to detect a trailing end of the sheet. A controller is configured to: in response to an elapse of a particular period after the sheet sensor detects the trailing end of the sheet, change a transfer bias to be applied to the transfer member from a first transfer bias to a second transfer bias, the second transfer bias having a smaller absolute value than the first transfer bias; and change the particular period based on the humidity detected by the humidity sensor.

Abstract: An image forming apparatus includes: a photosensitive drum; a magnetic roller; a transfer belt; a drum cleaning roller for collecting toner on the photosensitive drum and discharging collected toner to the photosensitive drum; a belt cleaner; a waste toner accommodating unit; and a controller configured to perform a printing operation for forming an image on a sheet and a cleaning operation for cleaning the drum cleaning roller. The controller is configured to perform: when performing the printing operation, collecting toner on the photosensitive drum using the drum cleaning roller; and when performing the cleaning operation, discharging the toner on the drum cleaning roller collected in the collecting to the photosensitive drum; transferring the toner on the photosensitive drum onto the transfer belt; and collecting the toner on the transfer belt using the belt cleaner so that the collected toner is accommodated in the waste toner accommodating unit.

Abstract: An image forming apparatus includes a main body including a display, a drum cartridge configured to be mounted to the main bod, a toner cartridge configured to be mounted to the drum cartridge, and a controller. The drum cartridge includes a photosensitive drum, a developing chamber configured to accommodate toner, and a drum memory. The toner cartridge includes a housing configured to accommodate the toner. The controller is configured to store, in the drum memory, a cumulative toner receiving amount which is a cumulative amount of the toner supplied from the toner cartridge and received in the developing chamber, a cumulative toner consumption amount which is a cumulative amount of the consumed toner, and a cumulative drum printing sheet number which is a number of sheets on which an image is formed.

Abstract: An image forming apparatus including a motor, a photosensitive drum, a developing roller, a main memory, and a controller. The controller is configured to perform storing a first rotation number and a second rotation number in the main memory. The first rotation number is the rotation number of the photosensitive drum rotated in a first state where the photosensitive drum rotates and the developing roller is stopped. The second rotation number is the rotation number of the photosensitive drum rotated in a second state where the photosensitive drum rotates and the developing roller rotates. The controller is further configured to perform, in a case where the photosensitive drum rotates, determining a total deterioration quantity of the photosensitive drum which is a cumulative deterioration quantity of the photosensitive drum based on the first rotation number and the second rotation number.

Abstract: An image forming apparatus includes a main body including a display, a drum cartridge configured to be mounted to the main bod, a toner cartridge configured to be mounted to the drum cartridge, and a controller. The drum cartridge includes a photosensitive drum, a developing chamber configured to accommodate toner, and a drum memory. The toner cartridge includes a housing configured to accommodate the toner. The controller is configured to store, in the drum memory, a cumulative toner receiving amount which is a cumulative amount of the toner supplied from the toner cartridge and received in the developing chamber, a cumulative toner consumption amount which is a cumulative amount of the consumed toner, and a cumulative drum printing sheet number which is a number of sheets on which an image is formed.

Abstract: An image-forming apparatus includes: a photosensitive drum, a motor, and a drum gear train configured to transmit a driving force from the motor to the photosensitive drum. The drum gear train includes a first gear, a second gear and a first clutch. The first gear is rotatable about a first axis upon receipt of the driving force. The second gear is rotatable about the first axis and configured to receive the driving force from the first gear and to transmit the driving force to the photosensitive drum. The first clutch is switchable between a first transmission state where the driving force is transmitted from the first gear to the second gear and a first transmission cutoff state where the transmission of the driving force from the first gear to the second gear is cut off.

Abstract: A developing cartridge includes a casing, a developing roller, a supply roller, a first agitator and a second agitator. The casing is configured to accommodate toner therein. The supply roller is configured to supply the toner to the developing roller. The first agitator is configured to agitate the toner in the casing. The second agitator is configured to agitate the toner in the casing. The second agitator is positioned between the first agitator and the supply roller. The second agitator includes a blade having a tip end configured to contact a peripheral surface of the supply roller.

Abstract: An image forming apparatus including a motor, a photosensitive drum, a developing roller, a main memory, and a controller. The controller is configured to perform storing a first rotation number and a second rotation number in the main memory. The first rotation number is the rotation number of the photosensitive drum rotated in a first state where the photosensitive drum rotates and the developing roller is stopped. The second rotation number is the rotation number of the photosensitive drum rotated in a second state where the photosensitive drum rotates and the developing roller rotates. The controller is further configured to perform, in a case where the photosensitive drum rotates, determining a total deterioration quantity of the photosensitive drum which is a cumulative deterioration quantity of the photosensitive drum based on the first rotation number and the second rotation number.

Abstract: An image-forming apparatus includes: a photosensitive drum, a motor, and a drum gear train configured to transmit a driving force from the motor to the photosensitive drum. The drum gear train includes a first gear, a second gear and a first clutch. The first gear is rotatable about a first axis upon receipt of the driving force. The second gear is rotatable about the first axis and configured to receive the driving force from the first gear and to transmit the driving force to the photosensitive drum. The first clutch is switchable between a first transmission state where the driving force is transmitted from the first gear to the second gear and a first transmission cutoff state where the transmission of the driving force from the first gear to the second gear is cut off.

Abstract: A developing cartridge includes a casing, a developing roller, a supply roller, a first agitator and a second agitator. The casing is configured to accommodate toner therein. The supply roller is configured to supply the toner to the developing roller. The first agitator is configured to agitate the toner in the casing. The second agitator is configured to agitate the toner in the casing. The second agitator is positioned between the first agitator and the supply roller. The second agitator includes a blade having a tip end configured to contact a peripheral surface of the supply roller.