A fixing device includes a fixing rotator, a hollow pressure rotator, a heater, a holder, and a bearing. The pressure rotator is configured to contact the fixing rotator. The heater is disposed inside the pressure rotator. The holder is configured to hold the pressure rotator and the heater. The bearing is configured to rotatably support the pressure rotator. The holder includes a curved face contact portion having a curved face conforming to an outer circumferential surface of the bearing to contact the bearing. The bearing includes a flange. The flange is configured to divide the bearing into an inboard area and an outboard area in an axial direction of the pressure rotator. The inboard area and the outboard area are asymmetrical.

A cleaning member for use in an image forming apparatus and configured to be inserted into the apparatus, the apparatus comprising a holding body that holds a substrate and lenses, the cleaning member comprising a rod, a cleaning portion provided in the rod to clean a light emission surface of each lens, a magnet attached to the rod, the magnet emitting a magnetic field to generates a magnetic force to draw the holding body thereto so that the cleaning portion maintains contact with the light emission surface, a yoke member attached to the rod and in contact with the magnet. The yoke member is configured to protrude, with respect to the magnet, towards a side on which the holding body is disposed, and a contact portion that is configured to contact the holding body and that to protrude, with respect to the yoke member, towards the above side.

A photosensitive member unit includes a photosensitive member, a rotary member, a charging roller, a separating member, and a one-way clutch. The charging roller is moved to and positioned at the separate position in a case where the photosensitive member rotates in the second direction when the separating member is positioned at the first position. The charging roller is moved to and positioned at the contact position in a case where the photosensitive member rotates in the first direction when the separating member is positioned at the second position.

An image-forming apparatus includes a photosensitive drum, a developing roller, a cam, a switching mechanism, a sheet tray, a sheet feed mechanism, a sheet sensor, and a controller. The switching mechanism rotates the cam to move the developing roller from a contact position in contact with the photosensitive drum to a separated position away from the photosensitive drum after development for the first sheet, if feeding of a second sheet is not started after elapse of a prescribed time period since detection of a first sheet. If image data for the second sheet is ready and upon elapse of a predetermined standby time period from elapse of the prescribed time period, the sheet feed mechanism starts feeding the second sheet toward the photosensitive drum and the switching mechanism rotates the cam to move the developing roller to the separated position in accordance with conveyance of the second sheet.

An image forming apparatus includes a driven unit and a drive transmitter. The drive transmitter includes a drive source, a drive gear, and a driven gear. The drive source is configured to drive the driven unit. The drive gear is configured to receive a driving force from the drive source. The driven gear is meshed with the drive gear. The drive transmitter is configured to transmit the driving force from the drive source to the driven unit. The drive gear or the driven gear is a crowned gear crowning-processed and the crowned gear has a crowning amount less than 50 m.

When a position of a developing unit with respect to a photoreceptor unit, the developing unit being mounted in an image forming apparatus, is switched to a contact position from a separation position with a switching unit, the developing unit at the contact position is brought to a state forming a predetermined space with the guide unit through which an airflow generated by a fan and that flows in a longitudinal direction of the guide unit flows, and when the position of the developing unit with respect to the photoreceptor unit, the developing unit being mounted in the image forming apparatus, is switched to the separation position from the contact position with the switching unit, the developing unit at the separation position is brought to a state in which the developing unit enters at least a portion of an area of the predetermined space.

An image forming apparatus comprises a main assembly of the image forming apparatus, with the main assembly including a driving shaft. The image forming apparatus also includes a cartridge detachably mountable to the main assembly of the image forming apparatus, the cartridge including (i) a photosensitive drum and (ii) a coupling positioned adjacent to an end portion of the photosensitive drum, with the coupling being movable in an axial direction of the photosensitive drum. The coupling is engageable with the driving shaft by the coupling moving in the axial direction in a state in which the cartridge is tilted relative to the main assembly of the image forming apparatus.

An image forming unit insertable into an image forming apparatus includes a photosensitive drum and a drum case supporting the photosensitive drum. The drum case includes a guide configured to (i) at least partially engage with a solid head of the image forming apparatus when inserted into the image forming apparatus along a first direction and (ii) guide the solid head in a second direction orthogonal to the first direction when the solid head is selectively repositioned along the second direction toward the photosensitive drum.

An image-forming apparatus includes a photosensitive drum, a developing roller, a cam, a switching mechanism, a cam follower, and a controller for controlling the switching mechanism to control rotation of the cam. The cam is rotatable to move the developing roller between a contact position in contact with the photosensitive drum and a separated position in separation from the photosensitive drum. To maintain the developing roller at the contact position after being moved from the separated position, the cam is rotated to move the cam follower from a first holding surface to a second holding surface of the cam through a second guide surface, and is stopped rotating to hold the cam follower in contact with a first guide surface of the cam at a position closer to the first holding surface than to the second holding surface.

A cleaning member for use in an image forming apparatus and configured to be inserted into the apparatus, the apparatus comprising a holding body that holds a substrate and lenses, the cleaning member comprising a rod, a cleaning portion provided in the rod to clean a light emission surface of each lens, a magnet attached to the rod, the magnet emitting a magnetic field to generates a magnetic force to draw the holding body thereto so that the cleaning portion maintains contact with the light emission surface, a yoke member attached to the rod and in contact with the magnet. The yoke member is configured to protrude, with respect to the magnet, towards a side on which the holding body is disposed, and a contact portion that is configured to contact the holding body and that to protrude, with respect to the yoke member, towards the above side.