An image forming apparatus includes a printing unit, first and second stacking units, first and second conveyance units, and a control unit. When the first conveyance unit conveys a sheet to the first stacking unit, the printing unit prints an image on a first number of sheets as first sheets in a first printing operation and prints the image on the first sheets in a second printing operation. When the second conveyance unit conveys the sheet to the second stacking unit, the printing unit prints the image on a second number of sheets, greater than the first number of sheets, as second sheets in the first printing operation and prints the image on the second sheets in the second printing operation. A number of sheets printed per unit time in the second printing operation is less than a number of sheets printed per unit time in the first printing operation.

A cartridge includes a photosensitive drum, the movable member movable relative to the photosensitive drum to control an inclination angle of a drive transmission member. The movable member is movable between a first position for reducing an inclination angle of the drive transmission member relative to the photosensitive drum and a second position retracted from the first position. By this, driving connection can be smoothly carried out.

An image forming apparatus includes an image forming part to form an image on a medium and a photo-finishing part to thermally transfer a coating film covering the image onto the medium.

An image forming apparatus includes a photoconductor, a charger, a detection unit, and a determination unit. The charger charges the photoconductor. The detection unit detects an actual charging potential of the photoconductor after the photoconductor is charged by the charger. The determination unit determines one of a plurality of causes related to a charging abnormality of the photoconductor based on a relationship between a standard charging potential of the photoconductor to be obtained by charging by the charger and a charging potential detected by the detection unit.

An image forming apparatus comprises: an image processor to convert image data based on a conversion condition; an image forming unit to form an image based on the converted image data using a replaceable member; a memory to store the image data and the converted image data; a sensor to perform measurement on a test image; and a controller. If the replacement of the replaceable member is detected while forming images, the controller controls the image forming unit to form the test image and generates the conversion condition based on a result of the measurement on the test image. If the replacement of the replaceable member is detected while forming the images, the controller further controls the image processor to convert the image data stored in the memory based on the generated conversion condition.

An image forming apparatus includes a reverse roller pair configured to reverse a conveyance direction of a recording medium between a first direction and a second direction, a first conveyance roller pair configured to convey the recording medium in the first direction, and a second conveyance roller pair configured to convey the recording medium in the second direction. A first distance is between the first conveyance roller pair and a reversal position in which a trailing edge of the recording medium is located when the conveyance direction is reversed. A second distance is between the reversal position and the second conveyance roller pair. An absolute value of a difference between the first distance and the second distance is an integer multiple of a circumferential length of a drive roller of the reverse roller pair or within a predetermined range from the integer multiple.

A controller is able to, in a case where the controller receives a correction instruction for image density, execute a phase detection mode for detecting a phase of an image bearing member and detecting a phase of a developer bearing member and change an image forming condition for an image forming unit during an image formation mode based on respective phases of the image bearing member and the developer bearing member detected in the phase detection mode and an image density of a toner pattern, and a ratio of a circumferential velocity of the developer bearing member to a circumferential velocity of the image bearing member during the phase detection mode is different from a ratio of a circumferential velocity of the developer bearing member to a circumferential velocity of the image bearing member during the image formation mode.

An image forming apparatus includes a reverse roller pair including a drive roller and a driven roller by which a recording medium is nipped and conveyed reversibly, a motor configured to rotate the drive roller reversibly, a conveyance roller pair, a detection unit configured to detect the recording medium conveyed by the conveyance roller pair, and a controller configured to control the motor, in a case in which the recording medium is detected by the detection unit, to cause the drive roller to rotate in a first rotation direction by a first rotation amount, thereafter to cause the drive motor to rotate in a second rotation direction by a second rotation amount. A difference between the first rotation amount and the second rotation amount is set to an integer multiple of a predetermined rotation amount of the motor, the predetermined rotation amount making the drive roller one rotation.

A housing includes a first opening and a second opening, and encloses a light-emitting element, a first light receiving unit, and a second light receiving unit. The first opening is provided in a first light guide path arranged between the light-emitting element and a first irradiated region of the target surface, and is arranged so that light output from the light-emitting element travels toward the first irradiated region. The second opening is provided in a second light guide path arranged between the first irradiated region and the first light receiving unit, and is arranged so that diffused reflection light from the toner image passes through when the toner image passes the first irradiated region.

An image reading apparatus including: a conveyance path; a light transmitting member; a first reading unit; a second reading unit; a first roller disposed opposite to the first reading unit; a second roller disposed opposite to the second reading unit; a holding member configured to hold the first roller and the second roller; a plurality of first abutment portions provided on both end portion sides in a width direction of the first roller and forming a gap between the light transmitting member and the first roller by abutting on the light transmitting member; a plurality of second abutment portions provided on both end portion sides in the width direction of the second roller and forming a gap between the light transmitting member and the second roller by abutting on the light transmitting member; and an urging member urges the holding member against the light transmitting member.