A sheet post-processing apparatus that performs post-processing on a sheet on which an image is formed includes: a punch hole forming portion; and a sheet bundle forming portion that has a conveyance portion, stops a first sheet on a conveyance path, and conveys a second sheet after the first sheet to a position overlapping the first sheet to form a sheet bundle. The sheet post-processing apparatus includes a shift portion to make a shift so that a relative position between the first sheet and the second sheet in a direction orthogonal to a conveyance direction becomes a relative position at which the second sheet does not overlap a punch hole of the first sheet to make the second sheet overlap the first sheet, and forms a sheet bundle in which sheets overlapped with each other are deviated in a width direction.

Provided is an image forming apparatus, including: an image bearing member; an exposure unit; a developing member which is rotatable at a rotation speed different from the image bearing member; a developer supply member; a developing voltage-applying unit; a supply voltage-applying unit; and a control unit. The control unit controls execution of: an image forming operation in which a developer image is formed by supplying developer on the image bearing member; and a cleaning operation which removes a substance adhered to the image bearing member using the developing member. In the cleaning operation, the control unit controls the developing voltage-applying unit or the supply voltage-applying unit so that the cleaning force using the developing member becomes stronger than that in the image forming operation.

An image forming apparatus includes an image forming unit configured to form an image on a recording material, a controller configured to control the image forming unit, a sheet feeding tray configured to store a recording material to be supplied to the image forming unit, and a sheet feeding tray cover configured to cover an access point of the sheet feeding tray. The sheet feeding tray cover includes a user interface for inputting information into a controller unit or outputting information from the controller.

A sheet feeder includes a sheet tray, a feed roller, a sheet feed frame, a contact element, a guide frame, a photosensor, a shield, and a linkage. The feed roller feeds a sheet on the sheet tray. The sheet feed frame holds the feed roller. The contact element is pivotable relative to the sheet feed frame. The guide frame is disposed below the sheet feed frame. The photosensor includes a light emitter and a light receiver. The shield is movable between a light transmission position and a light shield position. The linkage connects the contact element and the shield such that the shield is movable as the contact element pivots. The light receiver receives the light emitted from the light emitter when the shield is at the light transmission position. The shield at the light shield position shields the light receiver from the light emitted from the light emitter.

A server apparatus including a first communication device and a first computing device. The first communication device communicates with an image forming apparatus via a network. The first computing device includes a processor, and acts as a data acquirer, a dimension reduction processor, and a residual service life calculator, when the processor executes a first control program. The data acquirer acquires observation data of a first number of dimensions from the image forming apparatus, via the first communication device. The dimension reduction processor converts the observation data of the first number of dimensions into characteristic data of a second number of dimensions fewer than the first number of dimensions. The residual service life calculator calculates a residual service life of a replaceable unit in the image forming apparatus, on a basis of the characteristic data.

An image forming apparatus includes: a photosensitive drum; a developing roller; a separation mechanism configured to switch a state of the photosensitive drum and the developing roller between a contact state and a separation state; a main memory storing therein a first rotation number and a second rotation number; and a controller configured to perform calculating a deterioration quantity of the photosensitive drum based on the first rotation number and the second rotation number in the main memory. A surface of the developing roller contacts a surface of the photosensitive drum in the contact state, whereas the surface of the developing roller is separated from the surface of the photosensitive drum in the separation state. The first rotation number is the number of rotations of the photosensitive drum in the contact state, and the second rotation number is the number of rotations of the photosensitive drum in the separation state.

Provided is an image forming apparatus including a printer controller configured to form an image on a sheet, a storage unit configured to store a plurality of adjustment conditions for adjusting a position on the sheet at which the image is to be formed, and a CPU. The CPU selects one of the plurality of adjustment conditions, adjusts the position at which the image is to be formed based on the selected adjustment condition, and causes the printer controller to form the image on the sheet.

A development system for an image forming apparatus includes a photosensitive drum having a drive plate to receive a driving force to rotate the photosensitive drum. The drive plate is provided on an end of the photosensitive drum. The development system also includes a developing roller having a clutch mechanism to dampen a force generated when the clutch mechanism engages the drive plate of the photosensitive drum. The clutch mechanism is provided on an end of the photosensitive drum.

An image forming apparatus, including: a housing; a photoconductor; a developing unit configured to form a developer image on the photoconductor; a developer cartridge storing developer, the cartridge being removably mountable on the housing, a supplier configured to supply the developer from the developer cartridge to the developing unit; and a controller configured to execute a first printing process of forming a developer image by use of the developer supplied from the developer cartridge, when the developer cartridge is being mounted on the housing, and a second printing process of forming a developer image by use of the developer remaining in the developing unit, when a usage amount of the developing unit is not less than a predetermined value and the developer cartridge is not being mounted on the housing, wherein the controller does not execute the second printing process when the usage amount is less than the predetermined value.

An image forming apparatus comprises a main unit, a main unit memory, a drum cartridge, a toner cartridge, and a controller. The main unit memory stores printer identification information. The drum cartridge comprises a drum memory that stores drum identification information. The toner cartridge comprises a toner memory that stores toner identification information. The controller is configured to store in the main unit memory the drum identification information stored in the drum memory and store in the drum memory the printer identification information stored in the main unit memory, if it determines that the drum cartridge installed in the main unit is new, and store in the main unit memory the toner identification information stored in the toner memory and store in the toner memory the drum identification information stored in the drum memory, if it determines that the toner cartridge installed in the main unit is new.