An image forming apparatus includes a developing device including a photosensitive unit having a photoreceptor and a developing unit having a developing. A light scanning unit including a light source may be included to generate light to form an electrostatic latent image on the photoreceptor through a window through which the light is transmitted, and shutter unit may be included to open and close the window. At least one pressing unit is provided to press the developing unit to cause the developing roller separated from the photoreceptor to contact the photoreceptor. The pressing unit may further cause the shutter unit to open and close the window. An operating unit is connected to the at least one pressing unit. The operating unit is movable between an operating position to generate a pressing force by the at least one pressing unit to press the developing unit to contact the photoreceptor and a standby position to release the pressing force.

An image forming apparatus may include a photosensitive member, a developing device including a developing roller, pressing members configured to engage with the developing device and springs configured to urge the pressing members. In some examples, each of the pressing members may be configured to contact and move the developing device between various positions based on the urging of the springs. Additionally or alternatively, various ends of a contact surface of the developing roller configured to contact developer may be disposed relative to an axis line of the developing roller and pressing surfaces of the pressing members.

An image forming apparatus includes: a casing; a toner cartridge; a drum cartridge; a main electrode; a first reading portion; and a controller. The toner cartridge is attachable to the drum cartridge and includes: a developing roller; and a developing electrode electrically connected to the developing roller. The drum cartridge is attachable to the casing and includes: a photosensitive drum; a pressing member; and a drum memory. The pressing member presses the toner cartridge toward the photosensitive drum so that an outer circumferential surface of the developing roller contacts an outer circumferential surface of the photosensitive drum. The drum memory stores a pressing force value indicating a pressing force to be applied by the pressing member. The controller is configured to perform: reading, through the first reading portion, the pressing force value from the drum memory; and applying a voltage to the main electrode based on the pressing force value.

An image forming apparatus capable of detecting a development nip disengaging error and a method of detecting a development nip disengaging error are provided. According to an example method, a test pattern is formed on a photoconductor of an image forming apparatus, the test pattern transferred to an intermediate transfer belt is detected through a sensor from a time when an operation of an adjusting member moving a developing roller is controlled such that the developing roller moves from a disengaging position where the developing roller is spaced from the photoconductor to disengage a development nip from the photoconductor to a developing position where the developing roller is in contact with the photoconductor to form the development nip, and whether the development nip disengaging error occurred is determined based on the detected test pattern.

An image forming apparatus according to the present embodiment comprises: a dither processing unit that applies a dither matrix to an image; an exposure unit that exposes an photosensitive drum to form an electrostatic latent image, based on the image to which the dither matrix has been applied; a development unit that develops, using a developing material on a developing roller, the formed electrostatic latent image; and a control unit that, based on a print setting change instruction by a user, increases a circumferential speed of the developing roller relative to the circumferential speed of the photosensitive drum and decreases a screen ruling of the dither matrix to be applied by the dither processing unit.

Measures for controlling an engagement force between a photo imaging plate and a developer roller in a printing device are described. A motor is operated to generate rotational motion. The rotational motion is translated into linear motion. The linear motion causes an adjustment to the engagement force between the developer roller and the photo imaging plate. A characteristic of the motor is monitored. The motor is controlled on the basis of the monitored characteristic in order to maintain a desired engagement force between the developer roller and the photo imaging plate.

A photosensitive drum is rotatably supported in a main body. A developing cartridge is detachably mountable on the main body in a state where the photosensitive drum is supported in the main body. The developing cartridge includes a developing device and a frame. The developing device includes a developing roller disposed in confrontation with the photosensitive drum to supply developer to the photosensitive drum when the developing cartridge is mounted in the main body, and a developer-accommodating portion configured to accommodate developer. The frame includes a waste-developer-accommodating portion configured to accommodate waste developer and supports the developing device that is movable relative to the frame. The frame is disposed on an opposite side of the developing roller from the photosensitive drum. An urging member is disposed between the frame and the developing device to urge the developing roller toward the photosensitive drum.

An image forming apparatus includes the following. An image carrier forms an electrostatic latent image by exposure. A developing apparatus stores a developing agent including toner and which develops the image carrier. A collector collects in the developing apparatus the developing agent scattered from the developing apparatus. An input unit is used by a user to select a screen type relating to a fineness of a halftone image. An adjuster is able to change strength of an electric field between the collector and the image carrier. A hardware processor which controls the adjuster to change the strength of the electric field according to the selected screen type.

A developer carrying device for carrying a developer in a developer carrying path includes a developer carrying part that carries the developer in the developer carrying path; and a carrying drive part that drives the developer carrying part, wherein the developer carrying part includes: a carrying spiral that is formed by winding a wire rod into a coil shape and is driven by the carrying drive part; and a carrying auxiliary member that is arranged on an inner side of the carrying spiral, and is driven by the carrying drive part and assists carrying of the developer by the carrying spiral.

An image forming apparatus includes a developing portion, a driving-side shaft coupling, a movement supporting mechanism, a movement member, a separating member, and a displacement member. The developing portion includes a developing roller that develops an electrostatic latent image formed on an image-carrying member, and a driven-side shaft coupling that is provided on the developing roller. The driving-side shaft coupling transmits driving force, via the driven-side shaft coupling, to the developing roller. The movement supporting mechanism movably supports the developing roller between a developing position and a separated position. The displacement member applies a force to the movement supporting mechanism, and positions the developing roller at the developing position. When the movement member moves further after the driven-side shaft coupling has separated from the driving-side shaft coupling, the displacement member moves the developing roller from the developing position to the separated position.