Abstract: A developing device includes a rotatable developer carrying member, a developer regulating member, and a cylindrical magnetic field generating member provided inside the developer carrying member and including a regulating magnetic pole provided opposed to the developer regulating member. A magnetic flux distribution provided by the regulating magnetic pole includes a first local maximum portion on a side upstream of a closest position between the magnetic field generating member and the developer regulating member, a second local maximum portion on a side downstream of the closest position, and a local minimum portion between the first local maximum portion and the second local maximum portion. A rectilinear line connecting the closest position and a center of the magnetic field generating member is positioned between the first local maximum portion and the second local maximum portion.

Abstract: A developing device has a developer carrier, a regulating member, a regulating pole, and a magnetic pole generation member. The regulating member has a magnetic body for regulating the thickness of developer on the surface of the developer carrier. The regulating pole is arranged inside the developer carrier to face the regulating member. The magnetic pole generation member is arranged upstream of the regulating member in the developer carrier rotation direction, and has a magnet for generating, at an end portion of the regulating member, a magnetic pole of a polarity different from that of the regulating pole. The regulating member has, in its side face, a depressed portion having an inner face with an arc-shaped cross-section. The magnetic pole generation member is cylindrical, with a radius substantially equal to that of the inner face of the depressed portion, and is rotatable while staying fitted in the depressed portion.

Abstract: A developing device includes a developer bearer, a developer regulator disposed opposite the developer bearer across a first gap, and an opposing member having an opposing face disposed opposing the developer bearer across a second gap wider than the first gap. The opposing face is disposed adjacent to and upstream from the developer regulator in a direction of rotation of the developer bearer. The opposing face is inclined relative to an orthogonal plane direction orthogonal to a side face of the developer regulator. The opposing face is inclined to progressively reduce a distance from the developer bearer to the opposing face in a direction of rotation of the developer bearer. A difference between the second gap and the first gap is not greater than 1.75 times as large as the first gap.

Abstract: In a developing device, a sheet member is provided via a gap at a second specific position in a specific region between a position on a downstream side in a first rotation direction relative to a first specific position, and a high-magnetic-force position at which an intensity of a magnetic force is the highest in a second region, on the outer circumferential surface of a developer carrying body. The sheet member limits a layer thickness of a two-component developer carried on the developer carrying body rotating in a second rotation direction. The sheet member is able to elastically deform in accordance with application of a pressing force equal to or greater than a tolerable value in the first rotation direction or the second rotation direction.

Abstract: A developing device includes a developer sleeve, a regulating portion including an edge portion at a closest position to a surface of the sleeve or a flat portion tilted, at the closest position, by an angle of 2 degrees or less relative to a contact flat plane contacting the surface of the sleeve, and a rectifying portion connected with the edge or flat portion. The rectifying portion has a concavely curved surface such that a rate of a decrease in a gap between the rectifying portion and the contact flat plane increases toward a downstream side of the developer feeding direction and is formed by smoothly connecting rectilinear or curved lines each of 0.2 mm or less except for the edge portion so that the gap between the rectifying portion and the contact flat plane monotonically decreases toward the downstream side of the developer feeding direction.

Abstract: Provided is a developing device that can restrain stress on a developer and improve image quality. This developing device (3a-3d) is provided with: a developing vessel (20) that accommodates the developer, which includes a magnetic carrier and toner; a supply transport screw (23b); a developing roller (31) that carries the developer supplied by the supply transport screw (23b); an ear cutting blade (32) that regulates layer thickness of the developer on the surface of the developing roller (31); and a magnet (50) magnetized on one surface and disposed on the upstream side of the ear cutting blade (32). The magnet (50) is disposed such that a magnetized surface (50a) faces the side of the developing roller (31).

Abstract: An image forming apparatus includes an image carrier, a developer container, a moving mechanism that moves a toner of a developer to the image carrier, a stirring and transporting member that transports the developer in the developer container to the moving mechanism, a layer thickness regulating member that regulates the layer thickness of the developer held by a developer holder of the moving mechanism, and a movement regulating unit that regulates movement of the developer. An end of the movement regulating unit at a stirring and transporting member side is located at the stirring and transporting member side with respect to a tangent line tangent to the outer circumference of the stirring and transporting member and passing through a position where the density of magnetic flux of an attraction magnetic pole of a magnet member of the moving mechanism on the surface of the developing holder is the highest.

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 developing device includes a first developing unit, a second developing unit, a rotating member, a magnetic pole forming member, a first separating pole, a second separating pole, a developer supplying unit, and a path formation member. The developing device is provided with a magnetic structure, in which, when a value of a magnetic flux density at which the developer is separated is a reference separation value, at a side of the first separating pole at the separation area of the second developing unit, a position where a magnetic flux density of a vertical component of a magnetic force becomes less than or equal to the reference separation value is disposed downstream in the direction of rotation of the rotating member of a position where a magnetic flux density of a horizontal component of the magnetic force becomes less than or equal to the reference separation value.

Abstract: A developing device includes a developer bearing member, a layer restricting member, a facing magnet and a nonmagnetic member. The developer bearing member has a sleeve for bearing magnetic toner and a fixed magnet included inside the sleeve. The layer restricting member faces one magnetic pole of the fixed magnet, is arranged at a distance from the sleeve and made of a magnetic material. The facing magnet is arranged upstream of the layer restricting member in a rotation direction of the sleeve and at a distance from the sleeve, includes a first facing surface facing a position overlapping with a position with a maximum magnetic force of the one magnetic pole and has a magnetic pole having the same polarity as the one magnetic pole on the first facing surface. The nonmagnetic member is connected at an upstream side of the facing magnet in the rotation direction.

Abstract: The development device includes a developer storage part storing a developer, a developer carrier having a carrying surface for carrying the developer and a first magnet, and receiving the developer from the developer storage part on the carrying surface while rotating in a predetermined direction, and supplying the developer to a predetermined image carrier, a magnetic member formed from a magnetic material, forming a predetermined regulatory gap with the carrying surface, and arranged opposite to the first magnet, a second magnet disposed more upstream than the magnetic member when viewed from the rotating direction of the developer carrier, and having a magnetic pole of the same polarity as the first magnet, and a deterioration suppressing part suppressing deterioration of the developer transported to the regulatory gap along with the rotation of the developer carrier.

Abstract: A developing device includes: a developing roller incorporating a fixed magnet body having a plurality of magnetic poles in a circumferential direction; a regulating member for regulating an amount of toner on the developing roller by means of a magnetic field formed by the regulating member and the fixed magnet body; and a magnetic-field generating member for scraping off, on an upstream of the regulating member in a rotational direction of the developing roller, toner which is not used for development on the developing roller. A relation Bm/Br>1 is satisfied, where Br represents a magnetic flux density of a distal end portion of the regulating member facing a surface of the developing roller and Bm represents a magnetic flux density of a distal end portion of the magnetic-field generating member facing the surface of the developing roller.

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 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 configured to develop a latent image with developer including toner and carrier includes a development roller configured to carry the developer. The development roller includes a stationary magnet-fixing member, a plurality of magnets fixed to an interior of the stationary magnet-fixing member to form a plurality of magnetic poles, and a cylindrical rotatable sleeve roller configured to revolve coaxially around the exterior of the magnet-fixing member. Magnetic force distribution of a portion of the plurality of magnetic poles is varied in an axial direction of the development roller at positions corresponding to an image forming area in the axial direction of the development roller, enabling the development device to transport and agitate the developer.

Abstract: The present invention provides a developing device which is capable of suppressing the generation of a fogging phenomenon and deposition of carrier particles to an electrostatic latent image carrier and developing the electrostatic latent image efficiently, the device includes a development sleeve and a magnet body onto which the sleeve is fitted, and using a two-component developer. An angular position which indicates the peak value of the magnetic flux density in the normal direction produced by a development pole of the magnet body is shifted downstream from the center position of the development pole in the direction of movement of the surface of a photosensitive member in a development region. The present invention also provides an image forming apparatus which can form high-quality images with reduced noise such as fogging by mounting the developing device.

Abstract: A method of manufacturing a developing agent regulating member is provided. The method includes providing a non-magnetic member and a magnetic member. The non-magnetic member and the magnetic member are fixed together by caulking such that an end face of the non-magnetic member and an end face of the magnetic member are substantially aligned with each other, and such that the non-magnetic member and the magnetic member are closely pressed together in order to reduce a gap between the non-magnetic member and the magnetic member. The end face of the non-magnetic member and the end face of the magnetic member are polished so as to prepare the regulating face of the developing agent regulating member by making the end face of the non-magnetic member and the end face of the magnetic member flush.

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 using a magnetic mono-component developing agent includes a rotary sleeve that accommodates a stationary magnet, and a toner layer thickness regulating member that regulates a thickness of a toner layer formed on the rotary sleeve. The toner layer thickness regulating member includes a blade formed of a plate-like member made of a magnetic material and a magnet attached to the blade on a side upstream in a rotation direction of the rotary sleeve. The magnet is disposed in such a manner that a direction of a magnetic field generated in a portion of the magnet on a side of the rotary sleeve is almost in parallel with the rotation direction of the rotary sleeve.

Abstract: An image forming apparatus comprises toner with a coloring agent including magnetic powder as a nucleus arranged on a surface of one side of each toner particle, a toner image forming medium on which a toner image is formed using the toner, and a magnetic substance arranged at an opposite position to the toner image formed on the toner image forming medium.

Abstract: In a color image forming apparatus comprising a plurality of developing devices each provided with a developing roller structured with a developing sleeve and a fixed magnetic pole member, an agitating member, a recovering and feeding member, a regulating member and a developing device casing member, at least one of the plurality of developing devices has a different developer storing capacity and a different outer diameter of the recovering and feeding member for the other developing devices and has the same angle allocation values among the plurality of fixed magnetic poles in the fixed magnetic pole member.

Abstract: A developing device is provided having a simple configuration by which a desired amount of developer can be delivered to an image bearing member, and there is provided an image forming apparatus having the developing device. A developing device includes a developing roller by which two-component developer is borne and delivered to a photoreceptor drum, a layer thickness-regulating member for regulating a layer thickness of the developer, and a magnetism-generating member for generating magnetism, and a control unit for controlling an amount of displacement of the magnetism-generating member. The control unit 23 controls an amount of displacement of the magnetism-generating member relative to the development sleeve.

Abstract: A developing apparatus in which a first magnet of a first developing sleeve includes a first magnetic pole near a potion opposing to an image bearing member, and a second magnetic pole being downstream of the first magnetic pole; and a second magnet of a second developing sleeve includes a third magnetic pole near a portion opposing to the first sleeve. Assuming that a magnetic force obtained by combining normal direction forces Fr1 and Fr2 of magnetic forces generated by the first and second magnets, respectively, near the first sleeve is Fr, a center direction component of the first sleeve of the force Fr becomes positive between the first magnetic pole and a peak value position of the second magnetic pole, and a center direction component of the force Fr becomes negative between the peak value position and the closest position between both sleeves.

Abstract: A develop unit is configured to include a developer roller having a developer sleeve and a magnetic roller with a magnetic pole, a supply path formed in parallel with an axial direction of the developer roller, a supply screw supplying the developer to the developer roller, and a first bulkhead forming the supply path. In the developer unit, the magnetic pole is disposed so that a normal line through a maximum magnetic flux density point in a circumferential direction coincides with a tangent line to an upper portion of the supply screw in a rotary direction, the maximum magnetic flux density point being a point at which a density of a magnetic flux from the magnetic pole is maximum on an outer surface of the developer sleeve.

Abstract: A developing unit in an image forming device is disclosed in which developer peeled off from a developing roller can be reliably retrieved to an agitation transport member and avoid being directly drawn thereto. A developing unit has a drawing magnetic pole and a peel-off magnetic pole. A first agitation transport member is arranged below a developing roller and agitates and transports the developer in the axial direction simultaneously and supplies it to the developing roller. A guide member has a sloping surface guiding the developer torn off from the developing roller to the first agitation transport member. The magnetic pole is arranged between horizontal positions of the sloping surface, and the magnetic pole is arranged horizontally outward of the lower end of the sloping surface.

Abstract: A developing agent regulating member and a method of manufacturing the same is provided. The method includes providing a non-magnetic member and a magnetic member. The non-magnetic member and the magnetic member are fixed together by caulking such that an end face of the non-magnetic member and an end face of the magnetic member are substantially aligned with each other, and such that the non-magnetic member and the magnetic member are closely pressed together in order to reduce a gap between the non-magnetic member and the magnetic member. The end face of the non-magnetic member and the end face of the magnetic member are polished so as to prepare the regulating face of the developing agent regulating member by making the end face of the non-magnetic member and the end face of the magnetic member flush.

Abstract: A developing device is disclosed which includes a fixed magnet roller 25 having a plurality of magnetic poles, a development roller 27 having a development sleeve 26 that is supported axially with the ability to rotate freely, and a magnetic sealing member 29 arranged at the end of the longitudinal direction X of the development sleeve 26. Further, the length of each of the plurality of magnetic poles not facing the magnetic sealing member 29 (in other words, the development pole SI, lead-in pole NI, and blade pole N3) of the fixed magnet roller 25 are shorter than the length of each of the plurality of magnetic poles facing the magnetic sealing member 29. Accordingly, the magnetic toner retained on the peripheral surface of the development sleeve 26 is guided to the development area side in the longitudinal direction X of the development sleeve 26.

Abstract: A developing device using a magnetic mono-component developing agent includes a rotary sleeve that accommodates a stationary magnet, and a toner layer thickness regulating member that regulates a thickness of a toner layer formed on the rotary sleeve. The toner layer thickness regulating member includes a blade formed of a plate-like member made of a magnetic material and a magnet attached to the blade on a side upstream in a rotation direction of the rotary sleeve. The magnet is disposed in such a manner that a direction of a magnetic field generated in a portion of the magnet on a side of the rotary sleeve is almost in parallel with the rotation direction of the rotary sleeve.

Abstract: A developing unit for an image forming apparatus using a two-property developer that induces a magnetic attraction force based on the slope of a curved line representing the magnetism of each magnetic pole of a magnetic field generating part of a developing roller and determining a developer-regulating position where the changes of the magnetic attraction force are minor based on the magnetic attraction force in order to assure stable transfer of the developer to a photoconductive medium.

Abstract: A developing device includes a rotatable developer carrying member for carrying a developer to develop an electrostatic image formed on an image bearing member with the developer; non-rotatable magnetic field generating means, disposed inside the developer carrying member, for magnetically attracting the developer on the developer carrying member; a regulating member for regulating an amount of the developer carried on the developer carrying member, wherein the developer carrying member is provided with a surface elastic layer, and the developer carrying member is press-contacted to the image bearing member, and wherein, the developer is an one component magnetic toner having an average circularity not less than 0.965, and an amount of the developer per unit area of the developer regulated by the regulating member is 5-14 g/m2, and an amount of electric charge thereof is 10-50 ?C/g.

Abstract: A method of developing a latent image formed on an image carrier with toner, including causing a developer carrier, which faces the image carrier and accommodates a magnet therein, to support a developer having a toner and a magnetic carrier supporting the toner and convey the developer to a developing zone between the developer carrier and the image carrier, and providing an apparent coating ratio M of a surface of the developer carrier coated with the developer. The coating ration M is, in a zone upstream of the developing zone in a direction of rotation of the developer carrier, expressed as M=?A2+? (%), where ? denotes a coefficient of the coating ratio, A2 denotes an amount of developer for a unit area, ? denotes a value determined by a powder characteristic of the developer for an apparent coating ratio calculated with A2=0, and the coating ratio M is between 90% and 120%.

Abstract: A magnetic toner contains, as a magnetic powder, magnetic iron oxide having an octahedral particle shape and an average particle diameter of 0.21 ?m or larger and containing 18% or more by weight of FeO. The magnetic toner is so prepared as to have a bulk density A (g/cm3) and a magnetic powder content B (% by weight) that fulfill the formulae 0.8?A/B×100?1.6 and 35?B?50. This alleviates the reddishness of images produced with the magnetic toner, and alleviates the disturbance of a thin toner layer on a developing sleeve and thus the fogging resulting therefrom.

Abstract: An electrophotographic image forming apparatus of the present invention frees images from various defects including the thinning of horizontal lines, the omission of the trailing edge of an image, background contamination, granularity particular to a halftone image, carrier scattering, and image noise. Further, the apparatus of the present invention solves problems ascribable to patches used to sense image density. Moreover, the apparatus of the present invention faithfully reproduces tonality and has a high developing ability.

Abstract: To control bending of a magnetic field generation unit provided inside a developer carrying member, a developing apparatus for developing an electrostatic image formed on an image bearing member according to the present invention includes: a developer container which contains a magnetic developer; first and second developer carrying members which carry the developer in the developer container to the image bearing member; and first and second magnetic field generation units which are fixedly arranged in the first and second developer carrying members. In the developing apparatus, the first magnetic field generation unit and the second magnetic field generation unit form a magnetic field for delivering the developer from the first developer carrying member to the second developer carrying member, and the developing apparatus further includes a magnetic unit which exerts a magnetic force, which resists a magnetic force caused by the magnetic field, on the first and second magnetic field generation units.

Abstract: An image forming apparatus of the present invention includes a developing device including a sleeve and a magnet roller fixedly accommodated in the sleeve. The magnet roller includes a main magnetic pole and an auxiliary magnetic pole adjoining it at a downstream side in the direction of rotation of the sleeve. A magnetic collection pole is positioned on the edge of an opening formed in a casing and facing a photoconductive drum. The collection pole forms a magnetic field that prevents a developer falling away from the sleeve from escaping the developing device via the opening.

Abstract: An electrophotographic image forming apparatus of the present invention frees images from various defects including the thinning of horizontal lines, the omission of the trailing edge an image, background contamination, granularity particular to a halftone image, carrier scattering, and image noise. Further, the apparatus of the present invention solves problems ascribable to patches used to sense image density. Moreover, the apparatus of the present invention faithfully reproduces tonality and has a high developing ability.

Abstract: A developing device for an image forming apparatus of the present invention includes a developing roller made up of a sleeve and a magnet roller and a doctor facing the surface of the sleeve. The edge of the doctor faces the sleeve at a particular position selected to stabilize the amount of a developer to be scooped up, protect the developer from deterioration, and allow an adequate amount of charge to deposit on the developer by friction.

Abstract: A developing device of the present invention includes an image carrier for forming a latent image thereon, and a developer carrier for depositing a developer thereon in the form of a magnet brush. The magnet brush is caused to contact the latent image to thereby develop it. The developer carrier includes a main magnetic pole for development and an auxiliary magnetic pole adjoining the main pole and helping the main pole exert a magnetic force. The developer carrier and said image carrier are spaced by a gap of 0.35 mm or above, but 0.5 mm or below. The developer carrier has a carrier packing ratio of 15% or above, but 45% or below, measured at the developing region.

Abstract: A developing device includes a developing container for containing therein a developer provided with a carrier and a toner, a conveying device for conveying the developer in the developing container, a developer bearing member for bearing thereon the developer conveyed by the conveying device, the developer bearing member conveying the developer to a developing portion for developing a latent image formed on an image bearing member, a magnetic field generating device provided in the developer bearing member for generating a magnetic field, the magnetic field generating device being provided with a first magnetic pole and a second magnetic pole provided so as to be adjacent to the downstream side of the first magnetic pole in the direction of rotation of the developer bearing member and having the same polarity as the first magnetic pole, and a regulating device for regulating the layer thickness of the developer on the developer bearing member at a location substantially opposed to the second magnetic pole.

Abstract: To control bending of a magnetic field generation unit provided inside a developer carrying member, a developing apparatus for developing an electrostatic image formed on an image bearing member according to the present invention includes: a developer container which contains a magnetic developer; first and second developer carrying members which carry the developer in the developer container to the image bearing member; and first and second magnetic field generation units which are fixedly arranged in the first and second developer carrying members. In the developing apparatus, the first magnetic field generation unit and the second magnetic field generation unit form a magnetic field for delivering the developer from the first developer carrying member to the second developer carrying member, and the developing apparatus further includes a magnetic unit which exerts a magnetic force, which resists a magnetic force caused by the magnetic field, on the first and second magnetic field generation units.

Abstract: The invention relates generally to processes for electrostatic image development, and setpoints that provide uniform image development. In particular, an apparatus and process having a magnetic brush that implements hard carriers and a rotating magnetic core within a shell is disclosed. The process implements one or more of the following optimum setpoints: a range of shell surface speeds that provide uniform toning density, a range of shell surface speeds that prevent toner plate-out, a skive spacing that minimizes sensitivity to variation, a magnetic core speed that minimizes sensitivity to variation, and an imaging member spacing that minimizes sensitivity to variation.

Abstract: In a two-component developing unit, by devising the layout of magnetic poles 6 (particularly a pickup magnetic pole 6b and a trimming magnetic pole 6c) of a magnet member 5 arranged inside a developer carrier 3, an excess portion of a developer G picked up onto the surface of the developer carrier 3 is allowed to drop in the vicinity of the height of the rotational center O of the developer carrier 3, and only the developer G restricted to a predetermined layer thickness is carried and transported to a development region m. A charging member 9 is disposed over a periphery of the developer carrier 3, as required. In addition, the layout of the magnetic poles 6 of the magnet member 5 arranged inside the developer carrier 3 is set variably between the time of development and the time of nondevelopment, and the amount of developer carried on the surface of the developer carrier and transported to the development region m is set to substantially zero at the time of nondevelopment.

Abstract: The invention relates generally to apparatus for electrostatic image development and, in particular, apparatus that implement a magnetic brush with a drum photoconductor. According to an aspect of the invention, a method and apparatus for developing an electrostatic image are provided implementing a drum photoconductor and a magnetic brush contacting the photoconductor. The magnet brush comprises a mixture of toner and hard magnetic carriers.

Abstract: The present invention provides a developing apparatus which has a developer carrying member opposed to an image bearing member for bearing a latent image and adapted to carry magnetic developer, a magnet provided within the developer carrying member and having one end secured to a frame of the apparatus, and a bearing fitted on other end of the magnet and adapted to rotatably support the developer carrying member, wherein a fitting portion between the magnet and the bearing has a non-circular shape.

Abstract: When the structure is arranged such that one of the repulsion poles is used as a developer layer thickness regulation pole, screw pitch-shaped density unevenness occurred at the rear end of a solid black image.

Abstract: An image forming method for improving developer recirculation capability within a developer unit includes the steps of magnetically adsorbing a developer having magnetism onto a developer carrier by the action of a magnetic field generated by a magnetic field generating member to form a magnetic lobe, regulating the amount of developer in the magnetic lobe in accompaniment with rotation of the developer carrier about a longitudinal central axis by a developer regulating member disposed in a developer carrier rotating angular region extending from a position of a normal magnetic flux density inflection point, at which a component of the magnetic field normal to the developer carrier becomes zero, to a position of a normal magnetic flux density peak, at which the component of the magnetic field normal to the developer carrier exhibits a maximum value, in a direction in which the developer carrier is rotated, and developing a latent image on an image carrier using the magnetic lobe having a regulated amount of d

Abstract: A developing apparatus includes a developer bearing member, a first magnetic pole and a second magnetic pole of a same polarity as that of the first magnetic pole, and a regulating member. A regulating portion of the regulating member is provided within a range from a point of the maximum magnetic flux density of the second magnetic pole and an angular point corresponding to a half of the half value width of the second magnetic pole at the downstream side in the rotating direction of the developer bearing member.

Abstract: For realizing a satisfactory and stable developing process, the charge state of a developer and the density of toner particles contained in the developer is kept constant in the developing process. A developing roller to be driven rotationally is provided in a developing tank containing a developer. The developer is sucked magnetically using the magnetic force of a magnet provided in a developing sleeve composing the developing roller. The developer is then fed into a developing area opposed to a photosensitive member, then collected into the developing tank after the developing process is ended. The magnet is composed of an odd number of magnetic poles; developing pole, feeding pole, magnetic force distribution adjusting pole, developer sucking pole, developer separating pole, auxiliary collecting pole, and collecting pole. Between the sucking pole and the developing pole, an even number of poles are disposed. Between the developing pole and the separating pole are disposed an even number of poles.

Abstract: A developing apparatus employing a three-pole stationary magnetic roller for use with a uni-component magnetic developer or toner. The apparatus includes a rotational sleeve which accommodates the stationary roller, a mixer disposed in a toner vessel for stirring the toner, and a toner layer thickness regulator disposed upstream in the sleeve rotation direction from the developing position at which the image on a photo-sensitive drum is developed. The magnetic roller has a developing pole located near the developing position, a blade-facing pole facing the toner layer thickness regulator, and a shield pole located downstream in the sleeve rotation direction from the developing position, where the blade-facing pole and the shield pole are of the opposite polarity to the developing pole. The blade-facing pole and the shield pole generate a repulsive magnetic field therebetween, where the toner that has been stirred in the vessel comes in contact with the sleeve.

Abstract: A developing device for an image forming apparatus such as a copying machine, a printer, or the like to develop an electrostatic latent image on an image carrier includes a toner carrier which moves while carrying a toner on its surface, and a regulating member for regulating the amount of toner on the toner carrier by applying a moving force to the toner in a direction opposite to the moving direction of the toner carrier. In a regulating portion defined by the regulating member, a convey force received by a toner portion, which does not contact the surface of the toner carrier, from the regulating member is larger than a convey force received from the toner carrier.