Abstract: A developing device includes a first developing roller including a first transport member that transports magnetic developer by rotating while being close to a latent-image carrier rotating in one direction and a first magnet member, a second developing roller including a second transport member that transports the developer by rotating while being close to the latent-image carrier at a position on a downstream side of the first developing roller in the one direction, and a second magnet member, and a regulation member that regulates transport amounts of the developer distributed to the first and second developing rollers to required transport amounts, and opposes the developing rollers with predetermined distances therebetween. The first and second developing rollers are spaced from each other. The regulation member is movably supported in an area closer to the latent-image carrier than a closest position between the first and second developing rollers.

Abstract: An object of the present invention is to provide a developing apparatus which is less affected by usage environments, has high development efficiency for long term use and can provide a high quality image without image density non-uniformity. The present invention relates to a developing apparatus wherein a magnetic toner-carrying member has a work function value at the surface thereof within a specific range, a toner regulating member which regulates toner carried on the magnetic toner-carrying member is made of a specific material at a portion contacting the magnetic toner, the magnetic toner has an average circularity of 0.950 or more and the magnetic toner has a surface tension index within a specific range.

Abstract: An object of the present invention is to provide a developing apparatus which can provide images having superior image density and less fogging. The present invention relates to a developing apparatus wherein a magnetic toner-carrying member has a work function value at the surface within a specific range, a toner regulating member which regulates toner carried on the magnetic toner-carrying member is formed by a specific material at a portion contacting the magnetic toner, and has a ratio [W/B] of the amount W of silica fine powder to the theoretical specific surface area B of the magnetic toner satisfying a specific relation.

Abstract: A developing device includes first and second developer carriers facing each other in a facing region, a regulating member that regulates a layer thickness of developer, and a separation member. The first and second developer carriers respectively include first and second magnetic members that are respectively magnetized with first and second facing magnetic poles having opposite polarities. The separation member separates the developer so that the developer is supplied toward the first and second developer carriers. The separation member is disposed such that distances between the separation member and the first and second developer carriers are the smallest in a region in which a magnitude of a combined magnetic field of the first and second magnetic poles locally decreases as compared with a case where at least one of the first and second developer carriers is independently disposed due to interaction between the first and second facing magnetic poles.

Abstract: A developing device having: a guide member creating a guide channel for guiding the developer being fed thereto while being supported on the developer support; and a regulating member regulating the amount of the developer that has passed through the guide channel, the guide member further creates a reflux channel in a gap from an inner surface of the housing, the reflux channel is connected to the guide channel via a communication channel such that the developer regulated by the regulating member returns toward an upstream end of the guide member, the upstream end of the guide member is disposed in a position opposed to the position where the magnetic flux density of the catch pole peaks, and the magnet assembly further includes a feeding pole that is disposed downstream of the catch pole and upstream of the developing pole, so as to be opposed to the guide channel.

Abstract: A repulsive magnetic field is formed in a section immediately upstream of a regulating blade, so that generation of a developing-agent stationary layer is suppressed or eliminated. Accordingly, a developing apparatus capable of stably maintaining the layer thickness of developing agent conveyed to a developing area for a long time is provided.

Abstract: A development unit includes: a developing vessel in which a developing agent is received; a developing member as defined herein; a supply member which is supported in the developing vessel and disposed to be opposed to the developing member, the supply member rotating the developing agent in the developing vessel while holding the developing agent on a surface of the supply member to thereby supply the developing agent held on the surface to the developing member; and a thickness limiting member as defined herein, and the supply member is supported movably in a direction to expand or reduce a gap between the thickness limiting member and the supply member so that the gap between the thickness limiting member and the supply member can be adjusted.

Abstract: An image forming apparatus includes a developer bearing member configured to bear a developer to develop a latent image, a developer regulating member configured to regulate an amount of the developer carried on the bearing member, a voltage application unit that can apply a plurality of direct current voltages of different values between the bearing member and the regulating member, and a current detection unit that can detect a plurality of direct currents of different values flowing in the regulating member when the voltage application unit applies the plurality of direct current voltages, wherein the image forming apparatus sets a direct current voltage value Vb applied by the voltage application unit when developing the latent image, so that the following expression is satisfied: |Vb|>|Vbmin|, where Vbmin indicates a direct current voltage value when the direct current detected by the current detection unit is a minimum value.

Abstract: A developing device includes a developer transport body having a rotating outer peripheral surface, a magnet member having a plurality of magnetic poles, a regulation member that regulates passage of the developer supplied on the outer peripheral surface, and an introduction member having an opposing face opposing the outer peripheral surface to form an introduction space. A regulation-assist magnetic pole, of the magnetic poles, is provided at a position shifted from a position opposing the regulation member toward an upstream side in a rotating direction of the developer transport body. At least an upstream end of the opposing face is located on a virtual line obtained by translating a tangent line to the developer transport body at a position opposing the regulation member to an end of the regulation member opposing the developer transport body or located closer to the outer peripheral surface than the virtual line.

Abstract: A developing device includes a developer storing portion, a developer carrying body, a first regulating member having a first regulating surface regulating a layer thickness of the developer on the developer carrying body, a second regulating member having a second regulating surface that is set so as to gradually become apart from the developer carrying body toward the upstream side with respect to the rotation direction of the developer carrying body to regulate an amount of the developer conveyed to the first regulating surface, the second regulating surface being arranged with a step formed between the second regulating surface and the first regulating surface, and a sheet member so attached to the second regulating surface as to cover at least a portion of the step between the first regulating surface and the second regulating surface.

Abstract: A developing device that includes a developing member, a cylindrical layer thickness regulation member and a guide surface. The developing member retains a developer supplied from a developer accommodation portion and, while rotating, supplies the developer to an image-bearing body. The layer thickness regulation member comes up against the developer retained at the surface of the developing member and regulates a layer thickness of the developer. The guide surface guides developer that has been rendered excess by the layer thickness being regulated by the layer thickness regulation member toward the developer accommodation portion. The guide surface is provided such that an angle that is formed between the guide surface and a tangent of the layer thickness regulation member at a point of intersection of a line of extension of the guide surface with the layer thickness regulation member is at least 90°.

Abstract: A development device includes a developer carrier; a layer-regulating rotating member that faces the developer carrier with a gap therebetween and rotates in a direction following the rotation of the developer carrier while regulating the thickness of a layer of developer on the developer carrier; a development controller that controls, during development, the developer carrier and the layer-regulating rotating member to rotate at respective predetermined speeds and develops an electrostatic latent image on an image carrier with the developer; and a discharge controller that controls, while development is stopped, the developer carrier to rotate at a predetermined speed while controlling the layer-regulating rotating member to rotate at a speed that changes intermittently such that the amount of developer passing the layer-regulating rotating member changes and any foreign matter and aggregates in the developer are discharged together with the layer of the developer whose thickness is changed on the developer

Abstract: In an electrophotographic (EP) printer, a rotatable member includes a deposition area and a non-deposition area. A toner supply supplies toner to the member, and a moving receiving member receives from the deposition area of the rotatable member while the rotatable member rotates. The rotatable member is cleaned with a selectively-retractable blade in mechanical contact with the member so that toner is removed from the deposition area while the rotatable member rotates. An artifact sensor automatically detects a toner image artifact on the receiver. A controller responsive to the artifact sensor causes the blade to retract when an artifact is detected, and a blade cleaner cleans the blade while the blade is not in mechanical contact with the member.

Abstract: Apparatus for removing toner after a selected time interval from a longitudinal member in a dry electrophotographic printer for printing a visible image on a receiver. An end block is disposed at one end of a rotatable development member, and a longitudinal member is disposed adjacent to the development member or photoreceptor and is connected to the end block. A backup bar is disposed adjacent to the photoreceptor and can selectively make physical contact with at least one point on the end block. When a measured time interval of printer operation reaches the selected time interval, a controller causes the backup bar to apply a selected force to the end block to cause toner on the longitudinal member to be removed from the member.

Abstract: A developing device includes: a developing device main body in which a developer chamber containing a developer is formed; a pressure application area forming unit that is provided in the developer chamber so as to form a pressure application area where pressure is applied to the developer in the developer chamber because of movement of the developer contained in the developer chamber; and a pressure regulating unit that regulates the pressure applied to the developer in the pressure application area in response to temperature of the developer in the pressure application area.

Abstract: A cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus includes a developer carrying member for developing an electrostatic latent image formed on an image bearing member, and an electroconductive developer layer thickness regulating member for regulating a layer thickness of a developer deposited on the developer carrying member. A part of the developer layer thickness regulating member is directly contactable to the main assembly electrical contact.

Abstract: An anti-accumulation section is provided at a section where an inner surface of a developer container abuts a surface of a doctor blade on an upstream side of a rotation direction of a developing roller. An angle between a surface of the anti-accumulation section facing the developing roller and the surface of the doctor blade on the upstream side of the rotation direction of the developing roller is set to be larger than an angle between a circle concentric with a cross section of the developing roller perpendicular to an extending direction of the developing roller and the surface of the doctor blade on the upstream side of the rotation direction of the developing roller at the section where the surface of the anti-accumulation section facing the developing roller and the surface of the doctor blade on the upstream side of the rotation direction of the developing roller abut.

Abstract: A developer regulating member regulates a thickness of a layer of a developer on a surface of a developer bearing body. The developer has a degree of circularity in a range from 0.94 to 0.97. The developer regulating member includes a resilient plate member composed of a metal material and having a bent portion. An outer surface of the bent portion contacts the surface of the developer bearing body so that a ridge line of the outer surface of the bent portion crosses a moving direction of the surface of the developer bearing body. A curvature radius R (?m) of the outer surface of the bent portion and a mean crystal grain diameter D (?m) of the metal material satisfy the relationship: 60×10?3×R?11?D?93.75×10?3×R?6.875.

Abstract: A two-component developing method, including regulating a two-component developer borne on a developer bearer with a doctor blade; and transferring the regulated two-component developer to the developer bearer to develop a latent image on an image bearer, wherein the two-component developer includes a pulverized toner having a volume-average particle diameter of from 3.0 to 6.0 ?m, including particles having a particle diameter not greater than 4.0 ?m in an amount not less than 30% by number, and including particles having a particle diameter not greater than 2.0 ?m in an amount not greater than 10% by number, and wherein the doctor blade has a surface regulating the developer at an upstream side relative to a rotational direction of the developer bearer, which has a surface roughness Ra not greater than 0.2 ?m.

Abstract: The typical configuration of the present invention includes a developer layer restriction member (41) for restricting a developer amount held on a rotatable development sleeve (4c) which carries a developer and conveys the developer to a development region opposite to a photoconductor drum (1), the developer being made by mixing a non-magnetic toner and a magnetic carrier. The present invention includes a substrate resin plate made of a resin, and a resin hard coat layer (41b) disposed on a surface of the developer layer restriction member (41), the resin hard coat layer being made by coating the substrate resin plate with a resin which is harder than the resin of the substrate resin plate.

Abstract: A developing device includes a developing container for accommodating a two-component developer; a developer bearing member for bearing and conveying the developer, a fixed magnet including a release pole for releasing the developer from the developer bearing member, being fixed to the inside of the developer bearing member; and a backflow prevention member that is a sheet-shaped member disposed along the entire length in the longitudinal direction of the developer bearing member so as to be upstream in the direction of rotation of the developer bearing member as viewed from the release pole, the backflow prevention member being disposed so that a proximal end portion thereof is fixed to an inside surface of the developing container, and a distal end portion thereof is in contact with or adjacent to the developer bearing member and facing downstream in the direction of rotation of the developer bearing member.

Abstract: Toner is removed, after a selected time interval, from a skive mount in a dry electrophotographic printer. An end block is disposed at one end of the rotatable development member, and a skive mount disposed adjacent to the development member connects a skive to the end block. A timing device measures a time interval of printer operation. At the selected time interval, a controller causes a backup bar to lift away from the photoreceptor, then, after a selected time delay, causes the backup bar to make physical contact with at least one point on the end block, so that the backup bar applies a selected force to the end block to cause toner on the skive mount to be removed.

Abstract: A blade for an electro-photographic device includes an elastic rubber member constituted by an edge portion and a base portion which are in contact with each other and are constituted by different materials, wherein the edge portion includes an edge subject to frictional wear in use and is made of ester polyurethane, and the base portion is adapted to be bonded to a support and is made of ether polyurethane. The blade undergoes minimal permanent deformation and offers excellent mechanical strength, wear resistance and compliance to the use environment.

Abstract: A cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus includes a developer carrying member for developing an electrostatic latent image formed on an image bearing member, and an electroconductive developer layer thickness regulating member for regulating a layer thickness of a developer deposited on the developer carrying member. A part of the developer layer thickness regulating member is directly contactable to the main assembly electrical contact.

Abstract: A developing device includes a developing roller, toner supplying roller, regulation blade, and casing. The developing roller faces an image carrier on which an electrostatic latent image is to be formed, and supplies toner to the image carrier. The toner supplying roller faces the developing roller, and supplies the toner to the developing roller. The regulation blade faces the toner supplying roller at predetermined distance. The casing houses the developing roller, toner supplying roller, and regulation blade. The casing includes a toner catching support member facing the developing roller or the toner supplying roller between the regulation blade and the image carrier. The developing device further includes a toner catching member, which is arranged along a longitudinal direction of the toner catching support member and catches toner that drops from the developing roller, and a vibration generating portion, which vibrates the toner catching member.

Abstract: A developing unit to develop an image on an image support body and an image forming apparatus employing the same. The developing unit includes a housing to contain a developer having a toner and a carrier, a magnetic cylinder including a catch pole to pick up the developer in the housing and a main pole arranged to face the image support body and to hold the carrier of the developer, a sleeve installed to rotate on the magnetic cylinder and on which a developer layer is formed, a thickness regulating member to regulate a thickness of the developer layer, and a width regulating member to regulate a width of the developer layer on the sleeve.

Abstract: A developer station for an electrographic printer is provided that reduces developer agitation. The developer station includes a sump of magnetic developer, and a magnetic brush roller mounted above said sump and having a rotatable magnetic core surrounded by a substantially cylindrical toning shell rotatably mounted with respect to the core. The toning shell defines a nip at its closest point to the photoconductor element. A toning shell and magnetic core radius along with the eccentric offset of the toning shell from the rotating magnetic core are used in combination with the magnetic properties of the rotating magnetic core to determine the radius of the toning shell and magnetic core to improve the skiving and removal of developer from the toning shell after the developer has passed through the nip with the photoconductor element.

Abstract: A developing device includes a developing sleeve for carrying a developer containing a magnetic carrier and a non magnetic toner; a magnet, provided in the sleeve and including a plurality of magnetic poles disposed along a circumferential direction of the sleeve, for carrying the developer on the sleeve; and a regulating member, provided opposed to the sleeve with a predetermined spacing in a region in which the magnetic poles different in polarity are adjacent to each other, for regulating an amount of the developer carried on the sleeve. The magnetic poles are disposed so that a circumferential direction component of a magnetic force acting on the magnetic carrier contacting at least a part of an upstream regulating surface of the regulating member with respect to the circumferential direction of rotation of the sleeve is opposite from the circumferential direction of the rotation.

Abstract: An image forming apparatus including a developing device includes: a housing for housing a developer that includes a carrier and a toner; a development sleeve that is installed rotatably in the housing and is cylindrical and; and a layer regulator installed in the housing in such a way that an end of the layer regulator is spaced apart from an outer circumference surface of the development sleeve, wherein the layer regulator has a stacked structure including a non-magnetic material layer as a substrate, a resin layer for aiding electrifying of the toner by the carrier, and a magnetic material layer for regulating uniformity of the developer. Thus, the developing device is fabricated by using a simple process with sustainable straightness of the layer regulator even when the layer regulator operates and without formation of a step or a space between a magnetic material and a non-magnetic material.

Abstract: The present invention provides a cleaning blade for an electrophotographic device, which, even when spherical (perfectly spherical or irregularly shaped), polymerized toner with a small particle diameter is used, can achieve sufficient abrasion resistance and sufficient cleaning ability (particularly cleaning ability under low-temperature and low-humidity conditions). The cleaning blade for an electrophotographic device includes an elastic rubber member; and a supporting member. The elastic rubber member has a double layer structure including an edge layer and a base layer. The edge layer is made of a material with a JIS-A hardness of 65° to 72° at 23° C. and a rebound resilience of 10 to 35%. The base layer is made of a material with a JIS-A hardness of 70° to 80° at 23° C. and a rebound resilience of 40 to 70%, the JIS-A hardness value being larger than the value of hardness of the edge layer.

Abstract: A fastening structure which fixes a doctor blade to a holder is provided, which includes a cylindrical portion provided on one surface of the holder with which a doctor blade is overlapped, a through hole having an inner diameter larger than an outer diameter of the cylindrical portion and penetrating through the doctor blade. In the fastening structure, while the cylindrical portion is inserted through the through hole with a gap between an outer circumference of the cylindrical portion and an inner circumference of the through hole, an end portion of the cylindrical portion is pressed to be expanded in an outer circumferential direction and then bent towards the doctor blade, to thereby fix the doctor blade to the holder by supporting it between the end portion and the one surface of the holder.

Abstract: A developing device includes a container storing a two-component developer including a toner and a carrier, a toner carrying body carrying the toner in the container and supplying the toner to a predetermined image carrying body by rotation, a restricting member held in press contact with the toner carrying body, and a restricting nip section formed between the toner carrying body and the restricting member. The restricting nip section selects only the toner in the two-component developer to form a uniform toner layer on the toner carrying body.

Abstract: A developing unit including a retainer receiving portion for receiving a developer retainer, a first agitation portion adjacent to the retainer receiving portion, a second agitation portion adjacent to the first agitation portion, a first conveyance member received in the first agitation portion and conveying a developer in the first agitation portion in a first conveyance direction, a second conveyance member received in the second agitation portion and conveying a developer in the second agitation portion in a second conveyance direction reverse to the first conveyance direction, and a magnetic member disposed between the second conveyance member and the developer retainer and having magnetism.

Abstract: A method of controlling the amount of developer entering a toning zone in an electrophotographic printer for printing an image on a moving receiver includes providing a rotatable development member for selectively supplying developer from a developer supply to the photoreceptor, the developer including toner particles and carrier particles. A photoreceptor is arranged with respect to the rotatable development member to receive toner and apply the received toner to the moving receiver to print the image. A skive is brought into proximity with the surface of the development member using an electromagnetic actuator.

Abstract: A developing cartridge includes a first frame including a first wall at one end thereof, a second frame including a pair of second walls facing with each other and a third wall that connects the pair of second walls, an opening that is formed by the first wall, the pair of second walls and the third wall, and a support that is interposed between the third wall and the first wall so as to support the first wall by the third wall.

Abstract: A developing apparatus in which one sleeve is swingable includes a first magnetic field generating member inside a first developer bearing member, a second magnetic field generating member inside a second developer bearing member, and a positioning unit configured to perform positioning of a swinging connecting member in the peripheral direction or to perform positioning of the swinging connecting member in the peripheral direction through connection thereto.

Abstract: A developing device for developing an electrostatic latent image formed on an photoreceptor drum with a dual-component developer, includes: a developing hopper for storing the developer; an agitation roller for conveying the developer while agitating; a developing roller which supplies the developer to a developing area located opposing the photoreceptor drum; a layer thickness-regulating member for regulating the layer thickness of the developer being conveyed by the developing roller; a flow-guide plate for flowing down the surplus developer that was rejected to a position away from the layer thickness-regulating member; a multiple number of partitioning ribs arranged upright on the flow-guided plate for flowing down the surplus developer in a predetermined direction while diffusing the developer with respect to the longitudinal direction of the developer roller; and a downflow direction control mechanism for controlling the downflow direction of the surplus developer regulated by the partitioning ribs.

Abstract: A developing device includes a developing roller; a housing that retains the developing roller such that the developing roller has exposed and unexposed portions, end portions of the housing having first faces curved along the unexposed portion and second faces facing inward; a layer-thickness regulating member having an edge near the developing roller; a first magnet including a first magnetic pole that attracts the developer and a second magnetic pole located downstream of the first magnetic pole and upstream of the exposed portion in a rotational direction of the developing roller, the second magnetic pole having a magnetic force of about 60 mT or less; second magnets retained on the first faces; and magnetic plates retained on the second faces and arranged such that developer chains formed thereon at the downstream ends in the rotational direction extend to positions upstream of the edge of the layer-thickness regulating member.

Abstract: A mold for use in producing a molded body of an elastomer has a holding layer and a releasing layer on an inner periphery surface of a main body of a die. The releasing layer is formed of an addition two-component liquid silicone having a polysilazane-based or polysiloxane-based chain as a main chain, contains 0.5 mass % or less of a component which volatilizes at a curing temperature of a liquid elastomer raw material, does not contain silica, has International Rubber Hardness Degree of 50 to 85 degrees, and contains a solid lubricant having an average particle size of 2 to 20 ?m. The present invention also provides a method for manufacturing a blade for an electrophotographic apparatus by using the mold and a developer amount controlling blade having specific load length ratio and ten-point average roughness in which a blade member is manufactured with the method.

Abstract: A developing device includes: a developer holding body including: a hollow development rotary body which is opposed to an image holding body capable of holding a toner image and has a smooth surface whose surface roughness is lower than or equal to 5 ?m in terms of maximum height; and a magnet member which is fixedly housed in the development rotary body and in which a plurality of magnetic poles are arranged alongside its periphery, the developer holding body operating in such a manner that developer containing toner and carrier is held on the development rotary body by magnetic force produced by the magnetic poles of the magnet member as the development rotary body is rotated; a layer regulating rotary body as defined herein; and a development driving device as defined herein.

Abstract: A metering skive for a developer roller which is adapted to shear and/or meter developer at a developer-skive interface while minimizing compression of the metered developer. The metering skive is adjustable to various shear angles and has a geometry which enables a portion of the developer flow to be sheared away toward a curved second surface of the metering skive while metering the developer flow in a manner which minimizes or reduces compression of the developer.

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 4a is separated into a toner agitating portion 21 and a toner supply portion 22 by a boundary wall 23 in which a first opening 28 and a second opening 29 are formed. Inside the toner agitating portion 21, an agitation paddle 24 is rotatably supported, and inside the toner supply portion 22, components such as a development roller 25, a toner supply roller 16, and a regulation member 27 made of metal for regulating the thickness of a thin toner layer formed on the development roller 25 and for electrically charging toner are provided. A groove 27a is formed in the regulation member 27 all along the length thereof.

Abstract: A developing blade (11) comprises a blade member (14) located along one side edge of a support member (12) and having a surface shape defined by a maximum height roughness Ry of 0.35 to 4.5 ?m and a length ratio under load tp (at a 30% cut level) of 15% or less. Such a developing blade is manufactured by bringing a top mold (2) having a mold surface (2A) with a cavity (4) formed for the formation of a blade member and a gate (6) in communication with the cavity (4) in alignment with a bottom mold (3) having a flat mold surface (3A) such that at least a part of the support member (12) is positioned in the cavity (4), clamping together both the top and bottom molds, and pouring a molding material from the gate (6) to fill in the cavity (4).

Abstract: A developing device 2 includes a control member 116 for controlling an amount of a developer supplied to an image bearing member 3 by causing a developer captured on a surface of a developing sleeve 119 to be uniform in layer thickness. The control member 116 is arranged to face, via the developing sleeve 119, one (120b) of a plurality of magnetic poles provided inside the developing sleeve 119. Further, the control member 116 is arranged to be in parallel with a developing roller 114 in an axial direction of a magnet fixing shaft 126. The control member 116 is such a non-magnetic member that the nearest part of the non-magnetic member from the developing roller 114 has been caused to be ferromagnetic and has been magnetic-field oriented.

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 to carry by rotation two-component developer to a development range to develop a latent image formed on a latent image bearer, a magnetic field generator disposed inside the developer bearer, a developer regulator for adjusting an amount of the developer on the developer bearer, positioned upstream from the development range in a rotational direction of the developer bearer and facing the developer bearer across a regulation gap, a supply compartment from which the developer is supplied by a developer agitator to the developer bearer, a collection compartment, a pre-regulation portion adjacent to and upstream from the developer regulator in the rotational direction of the developer bearer, and a developer mobility adjuster that makes mobility of the developer in the pre-regulation portion higher on an upstream side in a developer conveyance direction in the supply compartment.

Abstract: A developing device, includes: a housing that stores toner inside; a toner carrier roller that is shaped approximately like a cylinder, is mounted to the housing rotatably about a rotational axis, rotates while carrying the toner on a surface thereof to convey the toner to outside of the housing, and is provided, on the surface thereof, with a plurality of convex sections which are regularly arranged and a concave section which surrounds the convex sections, the convex sections including top surfaces that coincide with a part of a curved surface of single cylinder and have electrical conductivity; and a seal member that is arranged in abutting contact with the surface of the toner carrier roller moving from the outside the housing toward the inside the housing at a position downstream of the opposed position in a rotation direction of the toner carrier roller to prevent toner leakage from the housing, a contact surface of the seal member being made of a material located at a position to charge the toner with

Abstract: A development device using a developing agent including a toner and a carrier, in which the development device includes a development roller that attaches the developing agent to a circumference surface of the development roller and transfers the developing agent to a development region in which the development roller faces a photo receptor; and a regulation portion to regulate an amount of the developing agent transferred to the development region, where the regulation portion includes first, second, and third regulation portions sequentially disposed in the stated order in an opposite direction to a rotational direction of the development roller, where the first, second, and third regulation portions are respectively spaced apart from the circumference surface of the development roller by first, second, and third intervals, the second interval is greater than the third interval, and the third interval is narrowed in the rotational direction of the development roller.

Abstract: A developer level control blade is provided which can form a developer layer on a developer carrying member in a proper thickness and in a uniform state and can keep the developer, in particular, color toner particles from melt-adhering to the charge control face so that faulty images such as lines and non-uniformity can be kept from occurring. Also provided is a process for manufacturing this developer level control blade. The process for manufacturing the developer level control blade is characterized by having the steps of extruding a blade member material melted to liquefy, covering therewith a support member thin-plate metal member at an edge portion thereof to join the both together, and cooling the blade member material to solidify, followed by cutting in a preset length.