Abstract: A developing device includes a developer bearer opposed to an image bearer, configured to bear developer and rotate in a direction of rotation of the developer bearer, and configured to develop a latent image on the image bearer and a casing opposed to the developer bearer at a position downstream from an opposed position, at which the developer bearer is opposed to the image bearer, in the direction of rotation of the developer bearer. A casing gap between the developer bearer and the casing continuously decreases or increases from a first end of the developing device to a second end of the developing device across a center of the developing device in a longitudinal direction of the developing device.

Abstract: An image forming apparatus includes an intermediate transferor, a plurality of image bearers, a plurality of developing devices, a plurality of developer containers, a plurality of conveyance paths, and a plurality of sub-hoppers. At least one set of an image bearer, a developing device, and a sub-hopper is disposed at a height different from other sets. The arrangement of the plurality of developing devices and the plurality of sub-hoppers in the rotation direction of the intermediate transferor is changed while satisfying the following. The arrangement of the plurality of developer containers is not changed and the connections between the plurality of developing devices and the plurality of sub-hoppers are not change, while the layout of the plurality of tubes as the plurality of conveyance paths is changed so that the connections between the plurality of tubes and the plurality of sub-hoppers are not changed.

Abstract: An image forming apparatus includes an intermediate transferor to rotate in a predetermined rotation direction, a plurality of image bearers disposed along the intermediate transferor to bear latent images, a plurality of developing devices to develop the latent images, a plurality of developer containers to contain developers, and a plurality of conveyance paths each corresponding to a respective one of the plurality of developing devices and a respective one of the plurality of developer containers to supply the developers to the plurality of developing devices respectively. An arrangement of the plurality of developing devices in the predetermined rotation direction is configured to be changed without changing an arrangement of the plurality of developer containers. A layout of the plurality of conveyance paths is configured to be changed without changing connections between a supply source and a supply destination of the plurality of conveyance paths.

Abstract: An image forming apparatus includes an intermediate transferor, a plurality of image bearers, a plurality of developing devices, a plurality of developer containers, a plurality of conveyance paths, and a plurality of sub-hoppers. At least one set of an image bearer, a developing device, and a sub-hopper is disposed at a height different from other sets. The arrangement of the plurality of developing devices and the plurality of sub-hoppers in the rotation direction of the intermediate transferor is changed while satisfying the following. The arrangement of the plurality of developer containers is not changed and the connections between the plurality of developing devices and the plurality of sub-hoppers are not change, while the layout of the plurality of tubes as the plurality of conveyance paths is changed so that the connections between the plurality of tubes and the plurality of sub-hoppers are not changed.

Abstract: A powder container for an image forming apparatus includes: a rotatable powder storage storing powder; an opening on one end of the powder storage, through which a nozzle can be inserted; and a scooping portion to scoop up powder on an opening side, and supply the powder to a powder receiving hole of the nozzle when the powder storage rotates. The scooping portion includes a scooping surface extending inwardly from an inner wall surface of the powder storage and an inner end portion extending in a rotation axis direction of the powder storage, with an edge approximately parallel to the rotation axis. In a cross-section perpendicular to the rotation axis, the scooping surface is inclined toward an upstream side in a rotation direction of the powder storage with respect to a virtual line that passes through the rotation axis and is tangent to the edge of the inner end portion.

Abstract: A powder container for an image forming apparatus includes: a rotatable powder storage storing powder; an opening on one end of the powder storage, through which a nozzle can be inserted; and a scooping portion to scoop up powder on an opening side, and supply the powder to a powder receiving hole of the nozzle when the powder storage rotates. The scooping portion includes a scooping surface extending inwardly from an inner wall surface of the powder storage and an inner end portion extending in a rotation axis direction of the powder storage, with an edge approximately parallel to the rotation axis. In a cross-section perpendicular to the rotation axis, the scooping surface is inclined toward an upstream side in a rotation direction of the powder storage with respect to a virtual line that passes through the rotation axis and is tangent to the edge of the inner end portion.

Abstract: A developing device includes a casing having an opening, the casing to contain developer, and a developer bearer including a magnetized range to cause developer to stand on end on a surface of the developer bearer and an end range outside the magnetized range in a longitudinal direction of the developer bearer. The developer bearer is disposed in the casing and partly exposed from the opening with a casing gap secured between the surface of the developer bearer and an inner face of the casing. The developer bearer generates, by rotation, sucked-in airflow to collect a floating toner from the opening into the casing, and the casing gap is smaller in the end range than the magnetized range.

Abstract: An image forming apparatus includes a latent image bearer having a shaft to rotate in a normal direction for image formation and a reverse direction, a charging device, a latent image forming device, a developing device including a developer bearer having a shaft, a driving source, a drive transmission device to transmit a driving force from the driving source to the shaft of the latent image bearer and the shaft of the developer bearer. The developer bearer rotates in a predetermined direction during image formation and transports developer including toner to a developing range facing the latent image bearer, thereby developing the latent image on the latent image bearer. The drive transmission device is configured to inhibit transmission of the driving force to the shaft of the developer bearer when the latent image bearer rotates in the reverse direction.

Abstract: A powder container contains powder and is attached to an image forming apparatus including: a conveying nozzle to convey the powder; a powder receiving hole of the conveying nozzle to receive the powder from the powder container; an apparatus main-body gear to transmit a driving force to the powder container; and a container receiving section including the conveying nozzle and receiving the powder container. The powder container includes: an opening at one end of the powder container in a longitudinal direction; a nozzle receiver at the opening to receive the conveying nozzle; a conveyor to convey the powder; and a container gear to drive the conveyor by meshing with the apparatus main-body gear. The container gear is to mesh with the apparatus main-body gear at a position closer to the opening than the powder receiving hole in the longitudinal direction. The opening is to mate with the container receiving section.

Abstract: A powder container contains powder and is attached to an image forming apparatus including: a conveying nozzle to convey the powder; a powder receiving hole of the conveying nozzle to receive the powder from the powder container; an apparatus main-body gear to transmit a driving force to the powder container; and a container receiving section including the conveying nozzle and receiving the powder container. The powder container includes: an opening at one end of the powder container in a longitudinal direction; a nozzle receiver at the opening to receive the conveying nozzle; a conveyor to convey the powder; and a container gear to drive the conveyor by meshing with the apparatus main-body gear. The container gear is to mesh with the apparatus main-body gear at a position closer to the opening than the powder receiving hole in the longitudinal direction. The opening is to mate with the container receiving section.

Abstract: An image forming apparatus includes a latent image bearer having a shaft to rotate in a normal direction for image formation and a reverse direction, a charging device, a latent image forming device, a developing device including a developer bearer having a shaft, a driving source, a drive transmission device to transmit a driving force from the driving source to the shaft of the latent image bearer and the shaft of the developer bearer. The developer bearer rotates in a predetermined direction during image formation and transports developer including toner to a developing range facing the latent image bearer, thereby developing the latent image on the latent image bearer. The drive transmission device is configured to inhibit transmission of the driving force to the shaft of the developer bearer when the latent image bearer rotates in the reverse direction.

Abstract: A developing device includes a casing having an opening, the casing to contain developer, and a developer bearer including a magnetized range to cause developer to stand on end on a surface of the developer bearer and an end range outside the magnetized range in a longitudinal direction of the developer bearer. The developer bearer is disposed in the casing and partly exposed from the opening with a casing gap secured between the surface of the developer bearer and an inner face of the casing. The developer bearer generates, by rotation, sucked-in airflow to collect a floating toner from the opening into the casing, and the casing gap is smaller in the end range than the magnetized range.

Abstract: A process cartridge is detachably mounted on an apparatus main body of an image forming apparatus. An embodiment of the cartridge includes a developer bearer arranged to be opposed to an image bearer in a developing device and rotates; a positioning member that supports the image bearer and the developer bearer at respective ends thereof, and fixes a distance between rotating shafts of the image bearer and the developer bearer; a rotating shaft arranged on a rotating member arranged on the developing device, and having a part protruding from an outer surface of a housing frame of the process cartridge; a gear that is arranged at a distal end of the rotating shaft and transmits a rotational driving force transmitted from the apparatus main body; and a bearing that is arranged between the positioning member and the gear, is fixed to the housing frame, and supports the rotating shaft.

Abstract: A powder container contains powder and is attached to an image forming apparatus including: a conveying nozzle to convey the powder; a powder receiving hole of the conveying nozzle to receive the powder from the powder container; an apparatus main-body gear to transmit a driving force to the powder container; and a container receiving section including the conveying nozzle and receiving the powder container. The powder container includes: an opening at one end of the powder container in a longitudinal direction; a nozzle receiver at the opening to receive the conveying nozzle; a conveyor to convey the powder; and a container gear to drive the conveyor by meshing with the apparatus main-body gear. The container gear is to mesh with the apparatus main-body gear at a position closer to the opening than the powder receiving hole in the longitudinal direction. The opening is to mate with the container receiving section.

Abstract: A developing device includes a developer bearer to carry developer, disposed facing an image bearer, a developer conveyance member disposed facing the developer bearer, to agitate and supply developer to the developer bearer, a decompression portion surrounded by upper walls of the developing device and including multiple vents arranged in a longitudinal direction of the developing device and a filter. A number of the multiple vents is greater in either end portion than in a center portion in the longitudinal direction of the developing device.

Abstract: A process cartridge is detachably mounted on an apparatus main body of an image forming apparatus and comprises: a developer bearer that is arranged to be opposed to an image bearer in a developing device and rotates; a positioning member that supports the image bearer and the developer bearer at respective ends thereof, and fixes a distance between rotating shafts of the image bearer and the developer bearer; a rotating shaft arranged on a rotating member arranged on the developing device, and having a part protruding from an outer surface of a housing frame of the process cartridge; a gear that is arranged at a distal end of the rotating shaft and transmits a rotational driving force transmitted from the apparatus main body; and a bearing that is arranged between the positioning member and the gear, is fixed to the housing frame, and supports the rotating shaft.

Abstract: A driving force transmission mechanism includes a connection for integrally rotating a driving shaft on the driving source side and a driven shaft of a rotary member. The connection includes a tubular boss portion; and a fitting shaft portion fitted into the tubular boss portion. An inner shaft portion is provided in a projecting manner from bottom center of the tubular boss portion toward inside the tubular boss portion. An inner recessed portion into which the inner shaft portion fits is provided in center of a leading edge plane for fitting of the fitting shaft portion. Micro gaps are provided between an inner surface of the tubular boss portion and an outer surface of the fitting shaft portion and between an inner surface of the inner recessed portion and an outer surface of the inner shaft portion.

Abstract: A toner container detachably attached to a toner-container holder of a main body of an image forming apparatus includes a container body that includes an opening, and discharges toner contained in the container body, from the opening; and a held portion that is held by the toner-container holder in a non-rotating manner. The held portion includes an open/close member for opening/closing the toner outlet in synchronization with an attachment/detachment operation of the held portion to/from the toner-container holder.