Abstract: An image forming apparatus includes an image carrier, a developing device, a detecting device and a vibration imparting device. The image carrier rotates around an axis. The developing device includes a developing member rotating around an axis at a position facing the image carrier and supplying a toner to the image carrier. The detecting device detects a number of the toner scattered from an inside to an outside of the developing device. The vibration imparting device imparts vibration to the toner accumulated near the developing member when the number of the toner detected by the detecting device satisfies a predetermined condition.

Abstract: A development unit including: a developer carrier configured to carry a developer, and capable of supplying the carried developer to an electrostatic latent image; and a developer supplying member configured to supply the developer to the developer carrier and having a surface thereof made of a foamed body. Relationships expressed by v<S/10 and S/Dv?125 are satisfied, where a cell opening size of the foamed body is S [?m], a volume mean particle diameter of the developer is Dv [?m], and a volume ratio of particles having a particle diameter of 5 [?m] or less to the total developer is v [%].

Abstract: An image forming apparatus has: a photoconductive drum that rotates; a developing roller that carries toner to be charged and to which a first voltage application portion outputting an AC voltage is connected; a contact member that makes contact with the photoconductive drum to remove residual toner; a detection portion for detecting occurrence of electric discharge between the developing roller and the photoconductive drum; and a developing unit that feeds toner to the developing roller, that supports the developing roller opposite the photoconductive drum with a gap secured in between, and that feeds toner to the developing roller with prescribed timing and for a prescribed time during electric discharge detection.

Abstract: A development agent supply device includes a casing having an opening and a development agent storage section, a development agent holding member housed in the casing such that a development agent holding surface thereof faces a developer-supplied device via the opening, a first electric-field transfer board that transfers development agent with a traveling-wave electric field along a down-facing development agent transfer surface in a predetermined direction from the development agent storage section to the opening and faces the development agent holding surface at a downstream end in the predetermined direction, and a second electric-field transfer board that includes a first section facing an downstream end of the first electric-field transfer board in the predetermined direction, and a second section facing the development agent holding member and transfers development agent received from the first electric transfer board at the first section, to the second section with a traveling-wave electric field.

Abstract: A developing device includes a developing container in which a developer is contained; a developer carrying member for carrying the developer and feeding the developer by rotation thereof to a developing zone in which the developer carrying member opposes an image bearing member on which a latent image is formed and develops the latent image with the developer; and an electrode, disposed opposed to the developer carrying member, to which a bias for forming an electric field for moving regular-charge toner in the developer container toward the developer carrying member is to be applied. The electrode is provided downstream of the developing zone with respect to a rotational direction of the developer carrying member and is provided vertically above the developer carrying member. At least a part of the electrode is located downstream of a rectilinear line connecting a rotation center and top point of the developer carrying member with respect to the rotational direction of the developer carrying member.

Abstract: An image forming apparatus is provided with a photoconductive member on which a latent image is to be formed, a developing roller for developing the latent image formed on the photoconductive member by a first bias, and a magnetic roller for forming a magnetic brush thereon with a two-component developer and forming a thin toner layer on the developing roller by a second bias. If (D1) denotes the duty ratio of a first alternating-current bias included in the first bias and (D2) denotes the duty ratio of a second alternating-current bias included in the second bias, the duty ratios (D1, D2) satisfy the following relationship: D1>100?D2.

Abstract: An image forming apparatus having a touchdown-development type developing apparatus, in which a toner collecting roller that collects scattered toner suspended in the vicinity of a toner holding body and a two-component developer holding body is arranged on the downstream side in a rotational direction of the two-component developer holding body from a closest position of the two-component developer holding body and the toner holding body, and between the two-component developer holding body and the housing wall, and further, bias means that applies a bias voltage for collecting the scattered toner to the toner collecting roller, and image density sensing means for sensing a density of a toner image developed on the electrostatic latent image holding body surface or a toner image on a transfer body onto which the toner image developed on the electrostatic latent image holding body surface is transferred to control the bias voltage are provided.

Abstract: A developing device includes a developing container in which a developer is contained; a developer carrying member for carrying the developer and feeding the developer by rotation thereof to a developing zone in which the developer carrying member opposes an image bearing member on which a latent image is formed and develops the latent image with the developer; and an electrode, disposed opposed to the developer carrying member, to which a bias for forming an electric field for moving regular-charge toner in the developer container toward the developer carrying member is to be applied. The electrode is provided downstream of the developing zone with respect to a rotational direction of the developer carrying member and is provided vertically above the developer carrying member. At least a part of the electrode is located downstream of a rectilinear line connecting a rotation center and top point of the developer carrying member with respect to the rotational direction of the developer carrying member.

Abstract: An apparatus includes an upstream transport surface TSa which, while facing a circumferential surface DS of a developing roller 33, is disposed upstream of an area (developing area) in the vicinity of a latent image forming surface LS, and a downstream transport surface TSb which, while facing the circumferential surface, is disposed downstream of the developing area. The apparatus forms electric fields on the upstream and downstream transport surfaces for moving a charged developer T from an upstream side toward a downstream side. In the apparatus, the transport speed of developer on the upstream transport surface is higher than that on the downstream transport surface. As a result, there can be lowered a speed at which the developer which has not adhered to the circumferential surface and has reached a downstream end portion of the upstream transport surface flies out toward the vicinity of the developing area.

Abstract: A developing device, process cartridge, and image forming apparatus that use ETH development, and are capable of forming good multi-color images with a simple construction, and are capable of preventing the dispersal of powder. The developing device is for developing latent images on a latent image carrying member by applying powder to the latent image carrying member, and comprises: a transport member disposed in opposition to the latent image carrying member and having a plurality of transport electrodes that generate a progressive wave electric field to move the powder; a voltage supply device for applying a multi-phase voltage to the transport electrodes; and a transport member surface potential determination device for determining the surface potential of the transport member.

Abstract: The image forming apparatus comprises: an ejection head which forms an image on an ejection receiving medium, by ejecting liquid having electrorheological properties onto the ejection receiving medium; a holding device which holds the ejection receiving medium on a surface facing a liquid ejection surface of the ejection head; a conveyance device which conveys at least one of the ejection head and the ejection receiving medium held by the holding device relatively to each other in a conveyance direction; a first electrode group which includes at least a pair of a positive electrode and a negative electrode provided in the holding device, has a lengthwise direction coinciding with a sub-scanning direction substantially parallel to the conveyance direction of the conveyance device, and is disposed so as to be aligned with the main scanning direction substantially perpendicular to the sub-scanning direction; and a voltage supply device which supplies a prescribed voltage to the first electrode group.

Abstract: A pulse-like DC voltage is applied from two power sources to transfer residual toner uniformizing means and toner charge amount control means, respectively, to expel transfer residual toner deposited on these means from these means onto a photosensitive drum. In a low humidity environment, the number of application of the DC voltage is increased so as to sufficiently expel the transfer residual toner because the transfer residual toner is less liable to be expelled even when the pulse-like DC voltage is applied to the above two means in the low humidity environment in which an absolute moisture content in atmosphere is small and electrical resistances at portions of a photosensitive drum contacting the above two means.

Abstract: An image forming device includes an image forming element moving past an image forming station in which a toner is deposited on the surface of the image forming element, the image forming element having at least one electrode extending over a predetermined surface area of the image forming element. The image device also includes an impedance/capacitance measuring circuit measuring the amount of toner deposited on the predetermined surface area on the basis of a resulting change in the impedance/capacitance of the electrode.

Abstract: An image transfer apparatus with the capacity to reduce or clean wire history. The cleaning is performed by supplying a voltage burst to shift, relative to nominal, the D.C. component of the electrode bias relative to the electrical bias of the donor member during the movement of the inter-imaging region through the development zone. A voltage shift may also be applied to electrically bias the donor member relative to the photoreceptor belt during the movement of the inter-imaging region through the development zone. These voltage shifts may be conducted individually or simultaneously.

Abstract: An automatic method for reading a graphic field on a ticket so that the ticket may be processed quickly without human error. The graphic field is designed to produce a “tell”, a visible known image (a large number of detectable halftone gray steps) when printed by a personal computer printer. Additionally, the graphic field will change in appearance when the ticket originally printed by the personal computer printer is digitally reproduced by either scanning or photocopying.

Abstract: A developing device includes a rotatable developer carrying member for carring a developer; a magnet roller provided in the developer carrying member; a first electrode portion connected electrically with the developer carrying member, the first electrode portion being rotatable with the developer carrying member; a second electrode portion provided with a contact portion in sliding contact with the first electrode portion, the contact portion being disposed outside a longitudinal end portion of the magnet roller substantially at a center of rotation of the developer carrying member.

Abstract: An image forming apparatus capable of obviating a defective image ascribable to image transfer and an image forming unit therefor are disclosed. A nonconductive sheet member is affixed to the surface of a conductive sheet member which will face a paper or similar recording medium, and protects the paper from the influence of a bias applied to the conductive sheet member. The paper is therefore free from a charge different in polarity from a transfer bias, so that toner is prevented from scattering toward the paper.

Abstract: An image forming apparatus is used, in which an electrostatic image formed on a moving image forming belt is developed by AC development. Where the image forming belt moves at a speed of v.sub.p mm/s, the cleaning potential is V.sub.cl volts, and the AC bias frequency is f kHz, the function Z satisfies the following equation: ##EQU1## Images substantially free of background development are thereby obtained.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; a first developing device for developing the electrostatic latent image on the image bearing member; a second developing device, faced to the image bearing member and having a movable developer carrying member for carrying toner and carrier, for effecting development after a first developed image provided by the first developing device passes through a position where the developer carrying member is faced to the image bearing member; and a preventing device for forming an alternating electric field between the developer carrying member and the image bearing member, while the second developing device is at reset to prevent the carrier of the second developing device from rubbing the first developed image.

Abstract: An image printing apparatus includes a number of image forming units for forming toner images of different colors in alignment on image receiving material in accordance with electronic image information signals fed to each image forming unit. Each image forming unit includes an image forming element rotatable about an axis of rotation and provided with a dielectric surface layer with adjacent electrode tracks in the direction of rotation. Each image forming unit further includes developing devices which include a linear developing magnet situated near the outer surface and parallel to the axis of rotation of the image forming element, toner feed devices for feeding a complete covering of electrically conductive and magnetically attractable toner powder to the image forming element, electrode track activating devices for applying a first or a second printing voltage between an electrode track and the magnet system in accordance with the image information signals to be fed to the image forming units.

Abstract: A development apparatus according to the invention comprises at least two developer carrier members in juxtaposition for transporting a developer material to a development region between the developer carrier members and an image bearing member in opposed relation. An AC voltage applying device is adapted to apply AC voltages to the respective developer carrier members thereby applying AC electric fields to the respective gaps between the developer carrier members and the image bearing member based on an active period to apply the AC electric field and an inactive period to apply no AC electric field. When one of the adjacent developer carrier members is subject to the active period, the other developer carrier member is subject to the inactive period.

Abstract: A donor roll for transporting marking particles to an electrostatic latent image recorded on a surface is provided. The donor roll includes a rotatably mounted body and an electrode member mounted on the body. The donor roll further includes a magnetically permeable core external to the body. The core rotates with the body. The core is composed of a plurality of wires. The donor roll further includes an electrically conductive material positioned on the core. The material is electrically connected to the electrode member.

Abstract: An image forming apparatus includes a photoconductor, a developing electrode, at least a magnet disposed in the developing electrode, and a developer. The developing electrode is reciprocally movable against a rotation axis of the photoconductor. Thus, a setting angle of a magnetic pole of the magnet is not varied, even when the developing electrode is moved for cancelling decentering and deflection of the photoconductor and the developing electrode.

Abstract: A non-contact type of developing device for use in an image forming apparatus having an image forming body, includes a developer conveying body facing the image forming body in which a magnet body having a plurality of magnet poles are attached therein, to convey two-component developer in the form of a developer layer onto a developing area and a control electrode provided at the developing area or upstream of the developing area. The control electrode has an electrically insulating member which is in contact with or close to the developing layer, and an electrode to which a voltage is applicable is attached to the insulating member. The following condition is satisfied: ##EQU1## where D.sub.T represents a number of toner layers on the assumption that the toner particles passing through the developing area are filled most densely, D.sub.WS represents a conveying amount (mg/cm.sup.2) of the developer layer at the developing area on the developer conveying body, T.sub.

Abstract: An apparatus for supporting wires in a wire module for use in a scavengeless development system using wire maintaining members that longitudinally support the wires. The tops of the wire maintaining members have grooves that positively position the wires and set a desired wire to wire spacing. The wire maintaining members are integral with the wire module and are part of a wire tensioning system. The wire maintaining members are part of an assembly that allow the wires to be pretensioned to the operable development tension prior to the wire module being mounted to the developer housing. The wire maintaining members also have a unique mounting system which allows the wire module to be rotatably mounted to the developer housing.