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 waste toner container includes a waste toner reservoir extending in a depth direction, an inlet portion provided above the waste toner reservoir, in which at least one waste toner inlet is formed, a first conveyance member provided in the waste toner reservoir to transport the waste toner in the depth direction, the first conveyance member movable upward as the amount of the waste toner in the waste toner reservoir increases, a second conveyance member provided in the inlet portion to transport the waste toner in a width direction and including a drive transmitter to transmit a driving force from the second conveyance member to the first conveyance member, and a waste toner detection unit to detect whether an amount of the waste toner in the waste toner container reaches a predetermined amount by detecting upward movement of the first conveyance member.

Abstract: A lubricant applicator includes a lubricant, a supply member contactable against the lubricant to supply the lubricant to a target, and a lubricant gauge to detect whether an amount of lubricant remaining is less than a threshold value. The lubricant gauge includes a rotary member rotatable about a shaft, a pressing member to press and rotate the rotary member as the lubricant is consumed, a contact part of the rotary member pressed by the pressing member, and a detection part of the rotary member opposite to the contact part across the shaft of the rotary member.

Abstract: An image carrier surface treatment device is disposed opposite an image carrier rotatable in a first rotation direction and carrying a toner image. The image carrier surface treatment device includes a roller rotatable in a second rotation direction while contacting an outer circumferential surface of the image carrier. The roller includes a shaft projecting from each lateral end of the roller in an axial direction thereof. A rolling-element bearing is fitted on the shaft of the roller to support and position the roller inside the image carrier surface treatment device.

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 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 process cartridge detachably installable in an image forming apparatus including a first sub-unit to hold an image carrier, a second sub-unit to hold a developer bearing member, a first positioning member to position first ends of the image carrier and the developer bearing member in a longitudinal direction, respectively, and a second positioning member to position second ends of the image carrier and the developer bearing member opposite the first ends in the longitudinal direction, respectively. The second sub-unit has a protruding portion protruding outward to a first end of the second sub-unit beyond the first positioning member in the longitudinal direction. An opposing surface of the protruding portion provided to face the first positioning member is dimensioned to conform to a cross-section of the first positioning member perpendicular to the longitudinal direction.

Abstract: An image forming apparatus includes an image carrier removably installed in the apparatus to carry an image; a transfer member contacting with the image carrier to transfer the image onto the transfer member or a recording medium; a contact and separation mechanism causing the transfer member to contact with or separate from the image carrier; and a removable unit removably installed in the apparatus from the same direction as an installation direction of the image carrier to be disposed proximal of the image carrier and the transfer member in the installation direction, and at least partially overlapping the image carrier and the transfer member as viewed in the installation direction. The removable unit interferes with the contact and separation mechanism and is prevented from being installed in the apparatus, when the transfer member is separated from the image carrier by the contact and separation mechanism.

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 unit includable in a process cartridge and in an image forming apparatus includes a developer bearing member including a magnetic field generator and a nonmagnetic hollow member, a developer container, an agitation/conveyance member, and a developer regulating member. The magnetic field generator has first and second magnetic poles to generate respective magnetic forces for removing the developer from the developer bearing member after the developer passes the development region. A developer-releasing region releases the developer from the developer bearing member using a release force. The developer is disposed higher than a surface of the developer in the developer storing chamber. A component of a magnetic flux density of the magnetic field generated by the magnetic field generator in a direction normal to the developer-releasing region is directed to a same direction as the first and second magnetic poles across the developer-releasing region without forming a local maximum point.

Abstract: A waste toner container includes a waste toner reservoir extending in a depth direction, an inlet portion provided above the waste toner reservoir, in which at least one waste toner inlet is formed, a first conveyance member provided in the waste toner reservoir to transport the waste toner in the depth direction, the first conveyance member movable upward as the amount of the waste toner in the waste toner reservoir increases, a second conveyance member provided in the inlet portion to transport the waste toner in a width direction and including a drive transmitter to transmit a driving force from the second conveyance member to the first conveyance member, and a waste toner detection unit to detect whether an amount of the waste toner in the waste toner container reaches a predetermined amount by detecting upward movement of the first conveyance member.

Abstract: A process cartridge for use in an image forming apparatus includes an image bearing member and a developing unit. The developing unit includes a developer bearing member to bear developer including toner and carrier, a casing forming a developer container containing the developer, a screw having a shaft with a spiral screw blade, a toner density sensor to detect a density of the toner on a detection surface, and a detection surface agitating member fixedly mounted on the shaft of the screw at a position facing a detection surface to scrape away the developer accumulated on the detection surface as the screw rotates. The detection surface agitating member includes an elastic sheet elastically deformable to scrape away the developer accumulated on the detection surface and disposed at a substantially same angle to an axial direction of the shaft of the screw as the spiral screw blade.

Abstract: A developing unit includable in a process cartridge and in an image forming apparatus includes a developer bearing member including a magnetic field generator and a nonmagnetic hollow member, a developer container, an agitation/conveyance member, a developer regulating member to regulate the thickness of a layer of the two-component developer. The magnetic field generator has first and second magnetic poles to generate respective magnetic forces for removing the developer from the developer bearing member after the developer passes the development region. The second magnetic pole generates a magnetic force to attract the developer to form a magnetic brush on the developer bearing member. The developer regulating member includes a magnetic member outwardly disposed on an exterior perimeter surface of the developer bearing member upstream from the developer regulating member, and one planar surface of the magnetic member faces the second magnetic pole across an effective development region.

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 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 carrier configured to carry developer and disposed in a development case, partly exposed from an opening of the development case facing an image carrier, a developer-transporting member configured to transport the developer to the developer carrier, and a discharging member housing a discharging space including a communicating path connecting to an area where the developer carrier faces the developer-transporting member, from which air is discharged into the discharging space, and a discharging port that opens in a longitudinal direction of the developer-transporting member, from which air is discharged from the discharging space.

Abstract: To downsize a developing device in the developing carrier axial direction without generating image concentration irregularities from recirculation of developer in the magnetic roller end regions, an N2 pole and an N3 pole, which are mutually adjacent having the same polarity (N polarity), and which are for generating a magnetic force for removing from a developing sleeve a developer that has passed through a developing region, are provided on a magnetic roller. Magnets of this developing device, which are for generating a magnetic field to displace to the inside in the axial direction magnetic force lines that cause peeling force in the direction of separation from the developing sleeve to act on developer on the developing sleeve, based on the magnetic force of the N2 pole and the N3 pole, and that pass through the axial direction end regions within a developer separation region on the developing sleeve, are provided on the outside of the magnetic roller.

Abstract: To downsize a developing device in the developing carrier axial direction without generating image concentration irregularities from recirculation of developer in the magnetic roller end regions, an N2 pole and an N3 pole, which are mutually adjacent having the same polarity (N polarity), and which are for generating a magnetic force for removing from a developing sleeve a developer that has passed through a developing region, are provided on a magnetic roller. Magnets of this developing device, which are for generating a magnetic field to displace to the inside in the axial direction magnetic force lines that cause peeling force in the direction of separation from the developing sleeve to act on developer on the developing sleeve, based on the magnetic force of the N2 pole and the N3 pole, and that pass through the axial direction end regions within a developer separation region on the developing sleeve, are provided on the outside of the magnetic roller.

Abstract: A developing unit includable in a process cartridge and in an image forming apparatus includes a developer bearing member including a magnetic field generator and a nonmagnetic hollow member, a developer container, an agitation/conveyance member, and a developer regulating member. The magnetic field generator has first and second magnetic poles to generate respective magnetic forces for removing the developer from the developer bearing member after the developer passes the development region. A developer-releasing region releases the developer from the developer bearing member using a release force. The developer is disposed higher than a surface of the developer in the developer storing chamber. A component of a magnetic flux density of the magnetic field generated by the magnetic field generator in a direction normal to the developer-releasing region is directed to a same direction as the first and second magnetic poles across the developer-releasing region without forming a local maximum point.