An image forming apparatus includes an image carrier to rotate about a rotation axis, a cleaning blade to contact a surface of the image carrier, and a protective agent coater. The protective agent coater has a rotatable shaft extending along the rotation axis of the image carrier, an elastic body formed around the rotatable shaft, and a waste toner supply member. The waste toner supply member supplies waste toner to the elastic body of the protective agent coater. The elastic body transfers protective agent from a protective agent supply to the image carrier. The protective agent coater is positioned upstream of the cleaning blade in the rotation direction of the image carrier.

An image forming apparatus comprises an image carrier to rotate about a rotation axis, a cleaning blade to contact a surface of the image carrier, and a protective agent coater. The protective agent coater has a rotatable shaft extending along the rotation axis of the image carrier, an elastic body formed around the rotatable shaft, and a waste toner supply member. The waste toner supply member supplies waste toner to the elastic body of the protective agent coater. The elastic body transfers protective agent from a protective agent supply to the image carrier. The protective agent coater is positioned upstream of the cleaning blade in the rotation direction of the image carrier.

An image forming apparatus includes an apparatus body, a photoconductor unit, and a developing cartridge. The apparatus body includes a controller and a body-side contact portion. The photoconductor unit includes a photoconductor, a charger, and a frame body. The developing cartridge includes a developing roller, a storage medium configured to store information, and a cartridge-side contact portion. The photoconductor unit includes a first contact portion configured to be electrically connected to tire body-side contact portion, a second contact portion configured to be electrically connected to the cartridge-side contact portion, and a wiring portion electrically connecting tire first contact portion and the second contact portion. The photoconductor unit further includes a separating member. The separating member is arranged to separate the charger and the part of the wiring portion when viewed in the rotational axis direction of the photoconductor.

An electrophotographic photoconductor in which a surface layer of a photosensitive layer or an overcoat layer has a glass transition temperature Tg greater than 100° C. and a hardness greater than 0.22 GPa. An electrophotographic cartridge and an electrophotographic imaging apparatus include the electrophotographic photoconductor. Flipping-over of a cleaning blade that comes into contact with the electrophotographic photoconductor may be effectively suppressed or prevented, the degree of freedom in terms of cleaning blade selection may be increased, and the possibility of causing high-frequency noise due to friction may be reduced.

An image forming unit forms an image on a sheet. A first generation circuit generates, regarding a member involved in image formation in the image forming unit, a first signal relating to a first abnormality. A second generation circuit generates, regarding the member, a second signal that relates to a second abnormality different from the first abnormality, and whose feature in a time axis direction or a frequency axis direction is different from that of the first signal. A control circuit has a single port to which the first signal and the second signal are to be input. The control circuit identifies between the first signal and the second signal based on a feature of a signal input to the port.

A rotary-body support structure includes: a rotary body including a rotary shaft and a contact portion spirally wound around the rotary shaft; and bearing parts that rotatably support the rotary body. The amount of engagement of the rotary body with a contact body that is in contact with the contact portion of the rotary body changes when the rotary body moves toward one side in a rotation axis direction.

A charging device includes: a charging roll configured to charge a photoconductor; a housing that houses the charging roll; and a heating unit that directly heats the housing or the charging roll. In the charging device, the heating unit may be disposed in contact with an outside or inside of the housing, and at least a part of the outside or inside of the housing may be covered with a thermally conductive member.

A charging device includes a charging roller, a cleaning roller, a pair of first supporting members, a pair of second supporting members and a pair of elastic members. The pair of first supporting members supports the charging roller in a rotatable manner. The pair of second supporting members supports the cleaning roller in a rotatable manner. The pair of elastic members is disposed between the first supporting members and the second supporting members, and pushes back the cleaning roller in a direction separate away from the charging roller. The second supporting member provided on one side in an axial direction of the cleaning roller has a roller-shift preventing part which blocks the cleaning roller. The elastic member provided on the one side in the axial direction pushes back the cleaning roller with force smaller than force of the elastic member provided on the other side in the axial direction.

A charging device includes a charger, a cleaner, and a separator. The charger is configured to charge an image holding unit. The cleaner is configured to clean the charger. The separator is configured, when the charging device has not yet been used, to separate the charger from the image holding unit and separate the cleaner from the charger.

A charging device includes a charger, a cleaner, and a separator. The charger is configured to charge an image holding unit. The cleaner is configured to clean the charger. The separator is configured, when the charging device has not yet been used, to separate the charger from the image holding unit and separate the cleaner from the charger.