Abstract: A process cartridge installed in a body of an image forming apparatus includes an image bearer, a development device that includes a developer bearer, a rotary developer conveyance member, and a shaft projecting from a development casing in an axial direction, a gear train including an idler gear provided to the shaft projecting from the development casing, a first side plate, and a hollow shaft projecting in the axial direction from the first side plate. The first side plate includes an image bearer positioning portion and a developer bearer positioning portion to support axial end portions of the developer bearer and the image bearer, the shaft projecting from the development casing is inserted into a recess inside the hollow shaft, and the hollow shaft is inserted into a hollow shaft positioning hole formed in the body.

Abstract: A development device includes a developer container for containing developer, a developer bearer to carry by rotation the developer contained in the developer container to a development range facing a latent image bearer, a partition dividing the developer container into an upper compartment and a lower compartment arranged vertically, an upper developer conveyance member disposed in the upper compartment, a lower developer conveyance member disposed in the lower compartment, a communication portion through which the developer moves from the lower compartment to the upper compartment, disposed in a downstream end portion of the lower compartment in a direction in which the lower developer conveyance member transports the developer, and a toner concentration detector to detect a concentration of toner in the developer beneath the communication portion inside the lower compartment.

Abstract: A development device includes a development casing, a developer bearer, a first developer conveyance member to supply developer to the developer bearer, a second developer conveyance member to transport developer axially, and a partition dividing an interior of the development casing into a supply channel and a collecting channel via which developer received from a downstream end portion of the supply channel is forwarded to an upstream end portion of the supply channel. The supply channel includes a conveyance area and a buffer area disposed adjacent to the conveyance area in a direction perpendicular to an axial direction to temporarily retain developer and midway in the developer conveyance direction inside the supply channel, and an upstream end face defining an upstream end of the buffer area is inclined relative to the axial direction to draw away from the conveyance area downstream in the developer conveyance direction.

Abstract: A development device includes a developer container, a developer carrier, exposed partly from a casing, facing a latent image carrier in a development area, a magnetic field generator inside the developer carrier, having multiple magnetic poles including a conveyance pole to convey the developer downstream from the development area to a developer release portion, a developer agitator, and a developer regulator. A predetermined gap is kept between an outer surface of the developer carrier and an inner wall of the casing downstream from an opening of the casing, upstream from a developer release portion, in a direction in which the developer carrier rotates. Multiple recesses are formed in the outer surface of the developer carrier at a pitch in a circumferential direction shorter than half a width of a magnetic flux density of the developer conveyance pole in a direction perpendicular to an axial direction of the developer carrier.

Abstract: A development device including a developer container, a developer bearer, a magnetic field generator, a developer agitator to supply the developer to the developer bearer, and a developer regulator to adjust a layer thickness of the developer carried on the developer bearer. Multiple oval recesses oblique to the axial direction of the developer bearer are formed in the outer circumferential surface of the developer bearer and arranged in a circumferential direction and the axial direction thereof. An upstream inner wall of the recess in the rotational direction of the developer bearer applies a force to the developer as the developer bearer rotates, and an angle between a long axis of the recess and the axial direction is set so that the force applied by the upstream inner wall of the recess has a component in a direction substantially identical to the developer conveyance direction of the developer agitator.

Abstract: A process cartridge installed in a body of an image forming apparatus includes an image bearer, a development device that includes a developer bearer, a rotary developer conveyance member, and a shaft projecting from a development casing in an axial direction, a gear train including an idler gear provided to the shaft projecting from the development casing, a first side plate, and a hollow shaft projecting in the axial direction from the first side plate. The first side plate includes an image bearer positioning portion and a developer bearer positioning portion to support axial end portions of the developer bearer and the image bearer, the shaft projecting from the development casing is inserted into a recess inside the hollow shaft, and the hollow shaft is inserted into a hollow shaft positioning hole formed in the body.

Abstract: A development device includes a development casing, a developer bearer, a first developer conveyance member to supply developer to the developer bearer, a second developer conveyance member to transport developer axially, and a partition dividing an interior of the development casing into a supply channel and a collecting channel via which developer received from a downstream end portion of the supply channel is forwarded to an upstream end portion of the supply channel. The supply channel includes a conveyance area and a buffer area disposed adjacent to the conveyance area in a direction perpendicular to an axial direction to temporarily retain developer and midway in the developer conveyance direction inside the supply channel, and an upstream end face defining an upstream end of the buffer area is inclined relative to the axial direction to draw away from the conveyance area downstream in the developer conveyance direction.

Abstract: There is provided a separation member for separating a first conveying path formed by a first conveying member from a second conveying path formed by a second conveying member. There is also provided an opposed member facing a magnetic pole H4 at an upstream side of two magnetic poles H4 and H6 that forms a developer-releasing magnetic pole H5.

Abstract: A development device includes a developer container for containing developer, a developer bearer to carry by rotation the developer contained in the developer container to a development range facing a latent image bearer, a partition dividing the developer container into an upper compartment and a lower compartment arranged vertically, an upper developer conveyance member disposed in the upper compartment, a lower developer conveyance member disposed in the lower compartment, a communication portion through which the developer moves from the lower compartment to the upper compartment, disposed in a downstream end portion of the lower compartment in a direction in which the lower developer conveyance member transports the developer, and a toner concentration detector to detect a concentration of toner in the developer beneath the communication portion inside the lower compartment.

Abstract: A development device including a developer container, a developer bearer, a magnetic field generator, a developer agitator to supply the developer to the developer bearer, and a developer regulator to adjust a layer thickness of the developer carried on the developer bearer. Multiple oval recesses oblique to the axial direction of the developer bearer are formed in the outer circumferential surface of the developer bearer and arranged in a circumferential direction and the axial direction thereof. An upstream inner wall of the recess in the rotational direction of the developer bearer applies a force to the developer as the developer bearer rotates, and an angle between a long axis of the recess and the axial direction is set so that the force applied by the upstream inner wall of the recess has a component in a direction substantially identical to the developer conveyance direction of the developer agitator.

Abstract: A powder container includes a cylindrical container body to contain a powder, having an opening in one end thereof, to convey the powder contained in the container body to the opening with rotation of the container body, and having a container-body projection provided on an outer circumferential surface of the container body; and a cylindrical holder, into which the end of the container body having the opening is inserted, to hold the container body rotatably, having a powder outlet through which the powder is discharged from the holder and a holder projection provided on an inner circumferential surface thereof. The container-body projection repetitively contacts and separates from the holder projection with rotation of the container body to vibrate the container body and the holder.

Abstract: A development device includes a developer container, a developer carrier, exposed partly from a casing, facing a latent image carrier in a development area, a magnetic field generator inside the developer carrier, having multiple magnetic poles including a conveyance pole to convey the developer downstream from the development area to a developer release portion, a developer agitator, and a developer regulator. A predetermined gap is kept between an outer surface of the developer carrier and an inner wall of the casing downstream from an opening of the casing, upstream from a developer release portion, in a direction in which the developer carrier rotates. Multiple recesses are formed in the outer surface of the developer carrier at a pitch in a circumferential direction shorter than half a width of a magnetic flux density of the developer conveyance pole in a direction perpendicular to an axial direction of the developer carrier.

Abstract: There is provided a separation member for separating a first conveying path formed by a first conveying member from a second conveying path formed by a second conveying member. There is also provided an opposed member facing a magnetic pole H4 at an upstream side of two magnetic poles H4 and H6 that forms a developer-releasing magnetic pole H5.

Abstract: Four fitting recessed portions 15A to 15D are provided in a connector housing 11, and four separate mating connectors in which ground wires are introduced, respectively, are allowed to be fitted into the fitting recessed portions so provided, respectively. A ground terminal 20 is formed by folding an elongate bus bar 21 in a plurality of stages, and each stage is formed into a configuration in which a plurality of tabs 23 are provided in a straight line along one or both edges of the bus bar 21. The ground terminal 20 is installed with tabs 23 being arranged so as to face the respective fitting recessed portions 15A to 15D and an ground plate 25 being made to protrude outwardly.