Abstract: A developing device, process cartridge and image forming apparatus of a premix developing system, with which developer splashed by the transport member is not discharged from the device, fluctuations of the amount of developer discharged to the outside are not produced, and the output image quality is stable. This developing device is provided with a pocket part, which is installed in a depressed manner facing the outside in relation to the transport route formed by the transport member, and into and out of which part of the developer transported in the transport route flows. This pocket part is provided with a discharge port for discharging developer to outside the device when the surface of the developer flowing into the pocket part exceeds a specified height.

Abstract: A development device includes a developer bearer, a developer regulator to adjust an amount of developer on the developer bearer, a supply compartment adjacent to the developer bearer across a side wall formed monolithic with the development casing using an identical material, a developer supply member to transport developer in the supply compartment in an axial direction, and a channel forming member having higher rigidity than that of the side wall. The channel forming member defines, with the side wall, a supply route extending over an entire development range, through which developer moves from the supply compartment to the developer bearer, and defines, with an inner wall of the development casing, a collecting route through which developer blocked by the developer regulator is collected in the supply compartment. Both axial end portions of the channel forming member are supported by the development casing.

Abstract: A development device includes a developer bearer to carry the developer to a development range, a magnetic field generator disposed inside the developer bearer for generating magnetic force, a developer regulator for adjusting an amount of the developer, a developer supply compartment disposed adjacent to the developer bearer, separated by a side wall from a portion where the developer bearer is provided, a developer agitator provided in the supply compartment, and a blocker disposed above the side wall of the supply compartment across a supply gap through which the developer moves from the supply compartment. The magnetic field generator has an attraction magnetic pole and a regulation magnetic pole. The blocker prevents the developer blocked by the developer regulator from moving along a magnetic force line of the regulation magnetic force toward the circumferential surface of the developer bearer.

Abstract: A powder container includes a powder chamber for containing powder for forming images, a powder outlet formed in a face of the powder container, and a shutter assembly to open and close the powder outlet and including first and second shutters. The first shutter is movable between a sealing position to close the powder outlet and an open position to open the powder outlet and includes a pressed member to cancel retention of the first shutter at the sealing position. The second shutter includes a pressing projection that interferes with the pressed member of the first shutter and is movable between a shielding position to cover the pressed member without interference between the pressing projection and the pressed member and a releasing position to press the pressed member with the pressing projection.

Abstract: A toner supply device including a casing and a shutter member. The casing includes a toner container for containing toner, a discharge aperture for discharging the toner from the toner container, and an aperture. The shutter member includes an elastic part having at least one bending portion and the elastic part is elastically deformable. The shutter member is insertable into the casing through the aperture to be movable between a closed position at which the discharge aperture is closed and an opened position at which the discharge aperture is opened while the elastic part is kept elastically deformed.

Abstract: A developing device, process cartridge, and image forming apparatus, include at least one developing roller. A plurality of transport members with screw and shaft portions, transport developing agent housed within the device in a longitudinal direction, and form a circulation path. A discharge aperture, formed in a transport path wall of one transport member, discharges developing agent to the outside when a surface of the developing agent transported by one of the plurality of transport members exceeds a predetermined height. The one transport member is adjacent to the developing roller that supplies the developing agent and includes, in a part in the longitudinal direction, an area on which the screw portion is not formed. The discharge aperture is disposed opposite to the area on which the screw portion is not formed, and the length of the discharge aperture is formed smaller than that of the area in the longitudinal direction.

Abstract: A developing device, process cartridge and image forming apparatus of a premix developing system, with which developer splashed by the transport member is not discharged from the device, fluctuations of the amount of developer discharged to the outside are not produced, and the output image quality is stable. This developing device is provided with a pocket part, which is installed in a depressed manner facing the outside in relation to the transport route formed by the transport member, and into and out of which part of the developer transported in the transport route flows. This pocket part is provided with a discharge port for discharging developer to outside the device when the surface of the developer flowing into the pocket part exceeds a specified height.

Abstract: A developing device, process cartridge and image forming apparatus of a premix developing system, with which developer splashed by the transport member is not discharged from the device, fluctuations of the amount of developer discharged to the outside are not produced, and the output image quality is stable. This developing device is provided with a pocket part, which is installed in a depressed manner facing the outside in relation to the transport route formed by the transport member, and into and out of which part of the developer transported in the transport route flows. This pocket part is provided with a discharge port for discharging developer to outside the device when the surface of the developer flowing into the pocket part exceeds a specified height.

Abstract: A development device includes a developer bearer to carry the developer to a development range, a magnetic field generator disposed inside the developer bearer for generating magnetic force, a developer regulator for adjusting an amount of the developer, a developer supply compartment disposed adjacent to the developer bearer, separated by a side wall from a portion where the developer bearer is provided, a developer agitator provided in the supply compartment, and a blocker disposed above the side wall of the supply compartment across a supply gap through which the developer moves from the supply compartment. The magnetic field generator has an attraction magnetic pole and a regulation magnetic pole. The blocker prevents the developer blocked by the developer regulator from moving along a magnetic force line of the regulation magnetic force toward the circumferential surface of the developer bearer.

Abstract: A developing device, process cartridge, and image forming apparatus, include at least one developing roller. A plurality of transport members with screw and shaft portions, transport developing agent housed within the device in a longitudinal direction, and form a circulation path. A discharge aperture, formed in a transport path wall of one transport member, discharges developing agent to the outside when a surface of the developing agent transported by one of the plurality of transport members exceeds a predetermined height. The one transport member is adjacent to the developing roller that supplies the developing agent and includes, in a part in the longitudinal direction, an area on which the screw portion is not formed. The discharge aperture is disposed opposite to the area on which the screw portion is not formed, and the length of the discharge aperture is formed smaller than that of the area in the longitudinal direction.

Abstract: A developing device, process cartridge, and image forming apparatus, have transport members with screw and shaft portions, transporting developer within the device in a longitudinal direction of a circulation path. A supply supplies new carrier to the device. A discharge aperture in a transport path wall of one transport member discharges developer outside the circulation path, when a surface of the developer transported by the one transport member exceeds a predetermined height. A bias path aperture in the transport path wall upstream of the discharge aperture has a bottom at a higher level than a bottom of the discharge aperture, and diverts developer at a level higher than the bottom of the discharge aperture to another transport member. An area in the longitudinal direction of the one transport member has no screw portion, and the discharge aperture is disposed opposite the area and has a length smaller than the area.

Abstract: A development apparatus includes a first developer chamber configured to store and supply the developer, a first developer bearer configured to convey the developer supplied from the first developer chamber to a first development domain, defined by a portion of the first developer bearer facing a latent image bearer, to develop the latent image, a second developer bearer configured to convey the developer passed through the first development domain to a second development domain, defined by a portion of the second developer bearer facing the latent image bearer, to develop the latent image, a second developer chamber configured to recover the developer passing through the second development domain and store the recovered developer, and a transfer prevention member provided between the second developer chamber and the second developer bearer to reduce a transfer of the developer from the second developer chamber to the second developer bearer.

Abstract: A developing device, process cartridge and image forming apparatus of a premix developing system, with which developer splashed by the transport member is not discharged from the discharge port, fluctuations of the amount of developer discharged to the outside are not produced, and the output image quality is stable. The transport member comprises, in a part thereof in the longitudinal direction, a cutaway region where the screw part is not formed. The discharge port faces the cutaway region, and is formed such that the longitudinal length thereof is smaller than that of the cutaway region. A wall part, which protrudes toward the interior of the transport route from a partition wall where the discharge port is formed, is then installed upstream of the transport route in relation to the discharge port and within the range of the cutaway region.

Abstract: A developing device is disclosed. The developing device includes a developing roller disposed to face an image carrier and a toner carrier capturing roller disposed to face the developing roller for capturing toner carriers adhered onto the image carrier. The developing roller generates a magnetic pole at a side facing the toner carrier capturing roller. A first virtual line, which connects a rotational center of the developing roller to a rotational center of the toner carrier capturing roller, passes through a region between a position where a magnetic flux density of the magnetic pole in the normal line direction is minimum on the developing roller at the upstream side in the rotational direction of the developing roller and a position where the magnetic flux density of the magnetic pole in the normal line direction is maximum on the developing roller.

Abstract: The developer conveyance amount on the upstream side of an agitation conveyance path in a developer conveyance direction becomes larger than the amount of developer to be transported from a recovery conveyance path to the agitation conveyance path, by making the developer conveyance amount on the upstream side of an agitating screw in the developer conveyance direction equal to or larger than the developer conveyance amount on the downstream side of a recovery screw in the developer conveyance direction. Accordingly, the bulk of the developer existing on the downstream side of the recovery conveyance path in the developer conveyance direction can be prevented from reaching the level where the recovered developer re-adheres to a developing roller, and further the developer existing on the downstream side of the recovery conveyance path in the developer conveyance direction can be prevented from re-adhering to the developing roller.

Abstract: A developing unit containing developer including carrier and toner and developing a latent image formed on an image carrier is disclosed. The developing unit includes multiple conveyor members configured to convey the contained developer in respective longitudinal directions so as to form a circulation channel; a supply part configured to supplement the carrier in the developing unit; a discharge part configured to discharge a first part of the contained developer outside the developing unit; and a bypass channel configured to cause a second part of the developer to return to the upstream side of the circulation channel without passing a position where the discharge part is provided.

Abstract: A disclosed developing device includes a developer carrier including a developing sleeve and a magnetic roller provided inside the developing sleeve. The magnet roller includes a regulating magnetic pole and a pump-up magnetic pole that have different polarities from each other. Among an entire region of the moving surface of the developing sleeve in the surface movement direction, a maximum pump-up magnetic force position where the pump-up magnetic force of the pump-up magnetic pole is maximum faces an upstream position with respect to a supplying position at which the developer is supplied from a supplying screw to the developing sleeve.

Abstract: A disclosed developing device is for accommodating a developer including carriers and a toner, and for developing a latent image formed on an image carrier. The developing device includes plural developer conveying units configured to convey the developer accommodated in the developing device and form circulating paths; and a ventilation unit configured to perform ventilation between at least one of the developer conveying units whose internal pressure increases and at least one of the developer conveying units whose internal pressure decreases.

Abstract: In a developing device, a receive-convey screw conveys a developer received from a developer carrier. The receive-convey screw includes a receive-convey blade including a lower, outer circumferential end located in a downstream end of the receive-convey blade in the developer conveyance direction of the receive-convey screw. A slant-convey screw is disposed obliquely relative to an axial direction of the receive-convey screw, and conveys the developer received from the receive-convey screw upward. The slant-convey screw includes a slant-convey blade including a lower, outer circumferential end located in an upstream end of the slant-convey blade in the developer conveyance direction of the slant-convey screw, the lower, outer circumferential end being located at a height level lower than the lower, outer circumferential end of the receive-convey blade.

Abstract: A bearing detachably and rotatably holds a photoconductor. A bearing holder firmly holds the bearing. A rotating lever is provided on a rotation axis of a photoconductor between the photoconductor and the bearing holder. The bearing holder and the rotating lever are provided with many protrusions at regular intervals. At a first relative position of the bearing holder and the rotating lever, the protrusions on the bearing holder are located in between the protrusions on the rotating lever. At a second relative position of the bearing holder and the rotating lever, the protrusions on the bearing holder ride on the protrusions on the rotating lever thereby pushing the photoconductor away from the bearing and detaching the photoconductor from the bearing.